Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

27 files changed, 11864 insertions, 0 deletions

diff --git a/security/keys/Kconfig b/security/keys/Kconfig
new file mode 100644
index 000000000..6462e6654
--- /dev/null
+++ b/security/keys/Kconfig
@@ -0,0 +1,103 @@
+#
+# Key management configuration
+#
+
+config KEYS
+	bool "Enable access key retention support"
+	select ASSOCIATIVE_ARRAY
+	help
+	  This option provides support for retaining authentication tokens and
+	  access keys in the kernel.
+
+	  It also includes provision of methods by which such keys might be
+	  associated with a process so that network filesystems, encryption
+	  support and the like can find them.
+
+	  Furthermore, a special type of key is available that acts as keyring:
+	  a searchable sequence of keys. Each process is equipped with access
+	  to five standard keyrings: UID-specific, GID-specific, session,
+	  process and thread.
+
+	  If you are unsure as to whether this is required, answer N.
+
+config KEYS_COMPAT
+	def_bool y
+	depends on COMPAT && KEYS
+
+config PERSISTENT_KEYRINGS
+	bool "Enable register of persistent per-UID keyrings"
+	depends on KEYS
+	help
+	  This option provides a register of persistent per-UID keyrings,
+	  primarily aimed at Kerberos key storage.  The keyrings are persistent
+	  in the sense that they stay around after all processes of that UID
+	  have exited, not that they survive the machine being rebooted.
+
+	  A particular keyring may be accessed by either the user whose keyring
+	  it is or by a process with administrative privileges.  The active
+	  LSMs gets to rule on which admin-level processes get to access the
+	  cache.
+
+	  Keyrings are created and added into the register upon demand and get
+	  removed if they expire (a default timeout is set upon creation).
+
+config BIG_KEYS
+	bool "Large payload keys"
+	depends on KEYS
+	depends on TMPFS
+	select CRYPTO
+	select CRYPTO_AES
+	select CRYPTO_GCM
+	help
+	  This option provides support for holding large keys within the kernel
+	  (for example Kerberos ticket caches).  The data may be stored out to
+	  swapspace by tmpfs.
+
+	  If you are unsure as to whether this is required, answer N.
+
+config TRUSTED_KEYS
+	tristate "TRUSTED KEYS"
+	depends on KEYS && TCG_TPM
+	select CRYPTO
+	select CRYPTO_HMAC
+	select CRYPTO_SHA1
+	select CRYPTO_HASH_INFO
+	help
+	  This option provides support for creating, sealing, and unsealing
+	  keys in the kernel. Trusted keys are random number symmetric keys,
+	  generated and RSA-sealed by the TPM. The TPM only unseals the keys,
+	  if the boot PCRs and other criteria match.  Userspace will only ever
+	  see encrypted blobs.
+
+	  If you are unsure as to whether this is required, answer N.
+
+config ENCRYPTED_KEYS
+	tristate "ENCRYPTED KEYS"
+	depends on KEYS
+	select CRYPTO
+	select CRYPTO_HMAC
+	select CRYPTO_AES
+	select CRYPTO_CBC
+	select CRYPTO_SHA256
+	select CRYPTO_RNG
+	help
+	  This option provides support for create/encrypting/decrypting keys
+	  in the kernel.  Encrypted keys are kernel generated random numbers,
+	  which are encrypted/decrypted with a 'master' symmetric key. The
+	  'master' key can be either a trusted-key or user-key type.
+	  Userspace only ever sees/stores encrypted blobs.
+
+	  If you are unsure as to whether this is required, answer N.
+
+config KEY_DH_OPERATIONS
+       bool "Diffie-Hellman operations on retained keys"
+       depends on KEYS
+       select CRYPTO
+       select CRYPTO_HASH
+       select CRYPTO_DH
+       help
+	 This option provides support for calculating Diffie-Hellman
+	 public keys and shared secrets using values stored as keys
+	 in the kernel.
+
+	 If you are unsure as to whether this is required, answer N.
diff --git a/security/keys/Makefile b/security/keys/Makefile
new file mode 100644
index 000000000..ef1581b33
--- /dev/null
+++ b/security/keys/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for key management
+#
+
+#
+# Core
+#
+obj-y := \
+	gc.o \
+	key.o \
+	keyring.o \
+	keyctl.o \
+	permission.o \
+	process_keys.o \
+	request_key.o \
+	request_key_auth.o \
+	user_defined.o
+compat-obj-$(CONFIG_KEY_DH_OPERATIONS) += compat_dh.o
+obj-$(CONFIG_KEYS_COMPAT) += compat.o $(compat-obj-y)
+obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_SYSCTL) += sysctl.o
+obj-$(CONFIG_PERSISTENT_KEYRINGS) += persistent.o
+obj-$(CONFIG_KEY_DH_OPERATIONS) += dh.o
+
+#
+# Key types
+#
+obj-$(CONFIG_BIG_KEYS) += big_key.o
+obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
+obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/
diff --git a/security/keys/big_key.c b/security/keys/big_key.c
new file mode 100644
index 000000000..630594a5b
--- /dev/null
+++ b/security/keys/big_key.c
@@ -0,0 +1,453 @@
+/* Large capacity key type
+ *
+ * Copyright (C) 2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "big_key: "fmt
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/file.h>
+#include <linux/shmem_fs.h>
+#include <linux/err.h>
+#include <linux/scatterlist.h>
+#include <linux/random.h>
+#include <linux/vmalloc.h>
+#include <keys/user-type.h>
+#include <keys/big_key-type.h>
+#include <crypto/aead.h>
+#include <crypto/gcm.h>
+
+struct big_key_buf {
+	unsigned int		nr_pages;
+	void			*virt;
+	struct scatterlist	*sg;
+	struct page		*pages[];
+};
+
+/*
+ * Layout of key payload words.
+ */
+enum {
+	big_key_data,
+	big_key_path,
+	big_key_path_2nd_part,
+	big_key_len,
+};
+
+/*
+ * Crypto operation with big_key data
+ */
+enum big_key_op {
+	BIG_KEY_ENC,
+	BIG_KEY_DEC,
+};
+
+/*
+ * If the data is under this limit, there's no point creating a shm file to
+ * hold it as the permanently resident metadata for the shmem fs will be at
+ * least as large as the data.
+ */
+#define BIG_KEY_FILE_THRESHOLD (sizeof(struct inode) + sizeof(struct dentry))
+
+/*
+ * Key size for big_key data encryption
+ */
+#define ENC_KEY_SIZE 32
+
+/*
+ * Authentication tag length
+ */
+#define ENC_AUTHTAG_SIZE 16
+
+/*
+ * big_key defined keys take an arbitrary string as the description and an
+ * arbitrary blob of data as the payload
+ */
+struct key_type key_type_big_key = {
+	.name			= "big_key",
+	.preparse		= big_key_preparse,
+	.free_preparse		= big_key_free_preparse,
+	.instantiate		= generic_key_instantiate,
+	.revoke			= big_key_revoke,
+	.destroy		= big_key_destroy,
+	.describe		= big_key_describe,
+	.read			= big_key_read,
+	/* no ->update(); don't add it without changing big_key_crypt() nonce */
+};
+
+/*
+ * Crypto names for big_key data authenticated encryption
+ */
+static const char big_key_alg_name[] = "gcm(aes)";
+#define BIG_KEY_IV_SIZE		GCM_AES_IV_SIZE
+
+/*
+ * Crypto algorithms for big_key data authenticated encryption
+ */
+static struct crypto_aead *big_key_aead;
+
+/*
+ * Since changing the key affects the entire object, we need a mutex.
+ */
+static DEFINE_MUTEX(big_key_aead_lock);
+
+/*
+ * Encrypt/decrypt big_key data
+ */
+static int big_key_crypt(enum big_key_op op, struct big_key_buf *buf, size_t datalen, u8 *key)
+{
+	int ret;
+	struct aead_request *aead_req;
+	/* We always use a zero nonce. The reason we can get away with this is
+	 * because we're using a different randomly generated key for every
+	 * different encryption. Notably, too, key_type_big_key doesn't define
+	 * an .update function, so there's no chance we'll wind up reusing the
+	 * key to encrypt updated data. Simply put: one key, one encryption.
+	 */
+	u8 zero_nonce[BIG_KEY_IV_SIZE];
+
+	aead_req = aead_request_alloc(big_key_aead, GFP_KERNEL);
+	if (!aead_req)
+		return -ENOMEM;
+
+	memset(zero_nonce, 0, sizeof(zero_nonce));
+	aead_request_set_crypt(aead_req, buf->sg, buf->sg, datalen, zero_nonce);
+	aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
+	aead_request_set_ad(aead_req, 0);
+
+	mutex_lock(&big_key_aead_lock);
+	if (crypto_aead_setkey(big_key_aead, key, ENC_KEY_SIZE)) {
+		ret = -EAGAIN;
+		goto error;
+	}
+	if (op == BIG_KEY_ENC)
+		ret = crypto_aead_encrypt(aead_req);
+	else
+		ret = crypto_aead_decrypt(aead_req);
+error:
+	mutex_unlock(&big_key_aead_lock);
+	aead_request_free(aead_req);
+	return ret;
+}
+
+/*
+ * Free up the buffer.
+ */
+static void big_key_free_buffer(struct big_key_buf *buf)
+{
+	unsigned int i;
+
+	if (buf->virt) {
+		memset(buf->virt, 0, buf->nr_pages * PAGE_SIZE);
+		vunmap(buf->virt);
+	}
+
+	for (i = 0; i < buf->nr_pages; i++)
+		if (buf->pages[i])
+			__free_page(buf->pages[i]);
+
+	kfree(buf);
+}
+
+/*
+ * Allocate a buffer consisting of a set of pages with a virtual mapping
+ * applied over them.
+ */
+static void *big_key_alloc_buffer(size_t len)
+{
+	struct big_key_buf *buf;
+	unsigned int npg = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	unsigned int i, l;
+
+	buf = kzalloc(sizeof(struct big_key_buf) +
+		      sizeof(struct page) * npg +
+		      sizeof(struct scatterlist) * npg,
+		      GFP_KERNEL);
+	if (!buf)
+		return NULL;
+
+	buf->nr_pages = npg;
+	buf->sg = (void *)(buf->pages + npg);
+	sg_init_table(buf->sg, npg);
+
+	for (i = 0; i < buf->nr_pages; i++) {
+		buf->pages[i] = alloc_page(GFP_KERNEL);
+		if (!buf->pages[i])
+			goto nomem;
+
+		l = min_t(size_t, len, PAGE_SIZE);
+		sg_set_page(&buf->sg[i], buf->pages[i], l, 0);
+		len -= l;
+	}
+
+	buf->virt = vmap(buf->pages, buf->nr_pages, VM_MAP, PAGE_KERNEL);
+	if (!buf->virt)
+		goto nomem;
+
+	return buf;
+
+nomem:
+	big_key_free_buffer(buf);
+	return NULL;
+}
+
+/*
+ * Preparse a big key
+ */
+int big_key_preparse(struct key_preparsed_payload *prep)
+{
+	struct big_key_buf *buf;
+	struct path *path = (struct path *)&prep->payload.data[big_key_path];
+	struct file *file;
+	u8 *enckey;
+	ssize_t written;
+	size_t datalen = prep->datalen, enclen = datalen + ENC_AUTHTAG_SIZE;
+	int ret;
+
+	if (datalen <= 0 || datalen > 1024 * 1024 || !prep->data)
+		return -EINVAL;
+
+	/* Set an arbitrary quota */
+	prep->quotalen = 16;
+
+	prep->payload.data[big_key_len] = (void *)(unsigned long)datalen;
+
+	if (datalen > BIG_KEY_FILE_THRESHOLD) {
+		/* Create a shmem file to store the data in.  This will permit the data
+		 * to be swapped out if needed.
+		 *
+		 * File content is stored encrypted with randomly generated key.
+		 */
+		loff_t pos = 0;
+
+		buf = big_key_alloc_buffer(enclen);
+		if (!buf)
+			return -ENOMEM;
+		memcpy(buf->virt, prep->data, datalen);
+
+		/* generate random key */
+		enckey = kmalloc(ENC_KEY_SIZE, GFP_KERNEL);
+		if (!enckey) {
+			ret = -ENOMEM;
+			goto error;
+		}
+		ret = get_random_bytes_wait(enckey, ENC_KEY_SIZE);
+		if (unlikely(ret))
+			goto err_enckey;
+
+		/* encrypt aligned data */
+		ret = big_key_crypt(BIG_KEY_ENC, buf, datalen, enckey);
+		if (ret)
+			goto err_enckey;
+
+		/* save aligned data to file */
+		file = shmem_kernel_file_setup("", enclen, 0);
+		if (IS_ERR(file)) {
+			ret = PTR_ERR(file);
+			goto err_enckey;
+		}
+
+		written = kernel_write(file, buf->virt, enclen, &pos);
+		if (written != enclen) {
+			ret = written;
+			if (written >= 0)
+				ret = -ENOMEM;
+			goto err_fput;
+		}
+
+		/* Pin the mount and dentry to the key so that we can open it again
+		 * later
+		 */
+		prep->payload.data[big_key_data] = enckey;
+		*path = file->f_path;
+		path_get(path);
+		fput(file);
+		big_key_free_buffer(buf);
+	} else {
+		/* Just store the data in a buffer */
+		void *data = kmalloc(datalen, GFP_KERNEL);
+
+		if (!data)
+			return -ENOMEM;
+
+		prep->payload.data[big_key_data] = data;
+		memcpy(data, prep->data, prep->datalen);
+	}
+	return 0;
+
+err_fput:
+	fput(file);
+err_enckey:
+	kzfree(enckey);
+error:
+	big_key_free_buffer(buf);
+	return ret;
+}
+
+/*
+ * Clear preparsement.
+ */
+void big_key_free_preparse(struct key_preparsed_payload *prep)
+{
+	if (prep->datalen > BIG_KEY_FILE_THRESHOLD) {
+		struct path *path = (struct path *)&prep->payload.data[big_key_path];
+
+		path_put(path);
+	}
+	kzfree(prep->payload.data[big_key_data]);
+}
+
+/*
+ * dispose of the links from a revoked keyring
+ * - called with the key sem write-locked
+ */
+void big_key_revoke(struct key *key)
+{
+	struct path *path = (struct path *)&key->payload.data[big_key_path];
+
+	/* clear the quota */
+	key_payload_reserve(key, 0);
+	if (key_is_positive(key) &&
+	    (size_t)key->payload.data[big_key_len] > BIG_KEY_FILE_THRESHOLD)
+		vfs_truncate(path, 0);
+}
+
+/*
+ * dispose of the data dangling from the corpse of a big_key key
+ */
+void big_key_destroy(struct key *key)
+{
+	size_t datalen = (size_t)key->payload.data[big_key_len];
+
+	if (datalen > BIG_KEY_FILE_THRESHOLD) {
+		struct path *path = (struct path *)&key->payload.data[big_key_path];
+
+		path_put(path);
+		path->mnt = NULL;
+		path->dentry = NULL;
+	}
+	kzfree(key->payload.data[big_key_data]);
+	key->payload.data[big_key_data] = NULL;
+}
+
+/*
+ * describe the big_key key
+ */
+void big_key_describe(const struct key *key, struct seq_file *m)
+{
+	size_t datalen = (size_t)key->payload.data[big_key_len];
+
+	seq_puts(m, key->description);
+
+	if (key_is_positive(key))
+		seq_printf(m, ": %zu [%s]",
+			   datalen,
+			   datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff");
+}
+
+/*
+ * read the key data
+ * - the key's semaphore is read-locked
+ */
+long big_key_read(const struct key *key, char *buffer, size_t buflen)
+{
+	size_t datalen = (size_t)key->payload.data[big_key_len];
+	long ret;
+
+	if (!buffer || buflen < datalen)
+		return datalen;
+
+	if (datalen > BIG_KEY_FILE_THRESHOLD) {
+		struct big_key_buf *buf;
+		struct path *path = (struct path *)&key->payload.data[big_key_path];
+		struct file *file;
+		u8 *enckey = (u8 *)key->payload.data[big_key_data];
+		size_t enclen = datalen + ENC_AUTHTAG_SIZE;
+		loff_t pos = 0;
+
+		buf = big_key_alloc_buffer(enclen);
+		if (!buf)
+			return -ENOMEM;
+
+		file = dentry_open(path, O_RDONLY, current_cred());
+		if (IS_ERR(file)) {
+			ret = PTR_ERR(file);
+			goto error;
+		}
+
+		/* read file to kernel and decrypt */
+		ret = kernel_read(file, buf->virt, enclen, &pos);
+		if (ret >= 0 && ret != enclen) {
+			ret = -EIO;
+			goto err_fput;
+		}
+
+		ret = big_key_crypt(BIG_KEY_DEC, buf, enclen, enckey);
+		if (ret)
+			goto err_fput;
+
+		ret = datalen;
+
+		/* copy out decrypted data */
+		memcpy(buffer, buf->virt, datalen);
+
+err_fput:
+		fput(file);
+error:
+		big_key_free_buffer(buf);
+	} else {
+		ret = datalen;
+		memcpy(buffer, key->payload.data[big_key_data], datalen);
+	}
+
+	return ret;
+}
+
+/*
+ * Register key type
+ */
+static int __init big_key_init(void)
+{
+	int ret;
+
+	/* init block cipher */
+	big_key_aead = crypto_alloc_aead(big_key_alg_name, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(big_key_aead)) {
+		ret = PTR_ERR(big_key_aead);
+		pr_err("Can't alloc crypto: %d\n", ret);
+		return ret;
+	}
+
+	if (unlikely(crypto_aead_ivsize(big_key_aead) != BIG_KEY_IV_SIZE)) {
+		WARN(1, "big key algorithm changed?");
+		ret = -EINVAL;
+		goto free_aead;
+	}
+
+	ret = crypto_aead_setauthsize(big_key_aead, ENC_AUTHTAG_SIZE);
+	if (ret < 0) {
+		pr_err("Can't set crypto auth tag len: %d\n", ret);
+		goto free_aead;
+	}
+
+	ret = register_key_type(&key_type_big_key);
+	if (ret < 0) {
+		pr_err("Can't register type: %d\n", ret);
+		goto free_aead;
+	}
+
+	return 0;
+
+free_aead:
+	crypto_free_aead(big_key_aead);
+	return ret;
+}
+
+late_initcall(big_key_init);
diff --git a/security/keys/compat.c b/security/keys/compat.c
new file mode 100644
index 000000000..e87c89c01
--- /dev/null
+++ b/security/keys/compat.c
@@ -0,0 +1,147 @@
+/* 32-bit compatibility syscall for 64-bit systems
+ *
+ * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/syscalls.h>
+#include <linux/keyctl.h>
+#include <linux/compat.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * Instantiate a key with the specified compatibility multipart payload and
+ * link the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+static long compat_keyctl_instantiate_key_iov(
+	key_serial_t id,
+	const struct compat_iovec __user *_payload_iov,
+	unsigned ioc,
+	key_serial_t ringid)
+{
+	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+	struct iov_iter from;
+	long ret;
+
+	if (!_payload_iov)
+		ioc = 0;
+
+	ret = compat_import_iovec(WRITE, _payload_iov, ioc,
+				  ARRAY_SIZE(iovstack), &iov,
+				  &from);
+	if (ret < 0)
+		return ret;
+
+	ret = keyctl_instantiate_key_common(id, &from, ringid);
+	kfree(iov);
+	return ret;
+}
+
+/*
+ * The key control system call, 32-bit compatibility version for 64-bit archs
+ *
+ * This should only be called if the 64-bit arch uses weird pointers in 32-bit
+ * mode or doesn't guarantee that the top 32-bits of the argument registers on
+ * taking a 32-bit syscall are zero.  If you can, you should call sys_keyctl()
+ * directly.
+ */
+COMPAT_SYSCALL_DEFINE5(keyctl, u32, option,
+		       u32, arg2, u32, arg3, u32, arg4, u32, arg5)
+{
+	switch (option) {
+	case KEYCTL_GET_KEYRING_ID:
+		return keyctl_get_keyring_ID(arg2, arg3);
+
+	case KEYCTL_JOIN_SESSION_KEYRING:
+		return keyctl_join_session_keyring(compat_ptr(arg2));
+
+	case KEYCTL_UPDATE:
+		return keyctl_update_key(arg2, compat_ptr(arg3), arg4);
+
+	case KEYCTL_REVOKE:
+		return keyctl_revoke_key(arg2);
+
+	case KEYCTL_DESCRIBE:
+		return keyctl_describe_key(arg2, compat_ptr(arg3), arg4);
+
+	case KEYCTL_CLEAR:
+		return keyctl_keyring_clear(arg2);
+
+	case KEYCTL_LINK:
+		return keyctl_keyring_link(arg2, arg3);
+
+	case KEYCTL_UNLINK:
+		return keyctl_keyring_unlink(arg2, arg3);
+
+	case KEYCTL_SEARCH:
+		return keyctl_keyring_search(arg2, compat_ptr(arg3),
+					     compat_ptr(arg4), arg5);
+
+	case KEYCTL_READ:
+		return keyctl_read_key(arg2, compat_ptr(arg3), arg4);
+
+	case KEYCTL_CHOWN:
+		return keyctl_chown_key(arg2, arg3, arg4);
+
+	case KEYCTL_SETPERM:
+		return keyctl_setperm_key(arg2, arg3);
+
+	case KEYCTL_INSTANTIATE:
+		return keyctl_instantiate_key(arg2, compat_ptr(arg3), arg4,
+					      arg5);
+
+	case KEYCTL_NEGATE:
+		return keyctl_negate_key(arg2, arg3, arg4);
+
+	case KEYCTL_SET_REQKEY_KEYRING:
+		return keyctl_set_reqkey_keyring(arg2);
+
+	case KEYCTL_SET_TIMEOUT:
+		return keyctl_set_timeout(arg2, arg3);
+
+	case KEYCTL_ASSUME_AUTHORITY:
+		return keyctl_assume_authority(arg2);
+
+	case KEYCTL_GET_SECURITY:
+		return keyctl_get_security(arg2, compat_ptr(arg3), arg4);
+
+	case KEYCTL_SESSION_TO_PARENT:
+		return keyctl_session_to_parent();
+
+	case KEYCTL_REJECT:
+		return keyctl_reject_key(arg2, arg3, arg4, arg5);
+
+	case KEYCTL_INSTANTIATE_IOV:
+		return compat_keyctl_instantiate_key_iov(
+			arg2, compat_ptr(arg3), arg4, arg5);
+
+	case KEYCTL_INVALIDATE:
+		return keyctl_invalidate_key(arg2);
+
+	case KEYCTL_GET_PERSISTENT:
+		return keyctl_get_persistent(arg2, arg3);
+
+	case KEYCTL_DH_COMPUTE:
+		return compat_keyctl_dh_compute(compat_ptr(arg2),
+						compat_ptr(arg3),
+						arg4, compat_ptr(arg5));
+
+	case KEYCTL_RESTRICT_KEYRING:
+		return keyctl_restrict_keyring(arg2, compat_ptr(arg3),
+					       compat_ptr(arg4));
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
diff --git a/security/keys/compat_dh.c b/security/keys/compat_dh.c
new file mode 100644
index 000000000..aa6b34caf
--- /dev/null
+++ b/security/keys/compat_dh.c
@@ -0,0 +1,40 @@
+/* 32-bit compatibility syscall for 64-bit systems for DH operations
+ *
+ * Copyright (C) 2016 Stephan Mueller <smueller@chronox.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/uaccess.h>
+
+#include "internal.h"
+
+/*
+ * Perform the DH computation or DH based key derivation.
+ *
+ * If successful, 0 will be returned.
+ */
+long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
+			      char __user *buffer, size_t buflen,
+			      struct compat_keyctl_kdf_params __user *kdf)
+{
+	struct keyctl_kdf_params kdfcopy;
+	struct compat_keyctl_kdf_params compat_kdfcopy;
+
+	if (!kdf)
+		return __keyctl_dh_compute(params, buffer, buflen, NULL);
+
+	if (copy_from_user(&compat_kdfcopy, kdf, sizeof(compat_kdfcopy)) != 0)
+		return -EFAULT;
+
+	kdfcopy.hashname = compat_ptr(compat_kdfcopy.hashname);
+	kdfcopy.otherinfo = compat_ptr(compat_kdfcopy.otherinfo);
+	kdfcopy.otherinfolen = compat_kdfcopy.otherinfolen;
+	memcpy(kdfcopy.__spare, compat_kdfcopy.__spare,
+	       sizeof(kdfcopy.__spare));
+
+	return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy);
+}
diff --git a/security/keys/dh.c b/security/keys/dh.c
new file mode 100644
index 000000000..711e89d8c
--- /dev/null
+++ b/security/keys/dh.c
@@ -0,0 +1,428 @@
+/* Crypto operations using stored keys
+ *
+ * Copyright (c) 2016, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/scatterlist.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/kpp.h>
+#include <crypto/dh.h>
+#include <keys/user-type.h>
+#include "internal.h"
+
+static ssize_t dh_data_from_key(key_serial_t keyid, void **data)
+{
+	struct key *key;
+	key_ref_t key_ref;
+	long status;
+	ssize_t ret;
+
+	key_ref = lookup_user_key(keyid, 0, KEY_NEED_READ);
+	if (IS_ERR(key_ref)) {
+		ret = -ENOKEY;
+		goto error;
+	}
+
+	key = key_ref_to_ptr(key_ref);
+
+	ret = -EOPNOTSUPP;
+	if (key->type == &key_type_user) {
+		down_read(&key->sem);
+		status = key_validate(key);
+		if (status == 0) {
+			const struct user_key_payload *payload;
+			uint8_t *duplicate;
+
+			payload = user_key_payload_locked(key);
+
+			duplicate = kmemdup(payload->data, payload->datalen,
+					    GFP_KERNEL);
+			if (duplicate) {
+				*data = duplicate;
+				ret = payload->datalen;
+			} else {
+				ret = -ENOMEM;
+			}
+		}
+		up_read(&key->sem);
+	}
+
+	key_put(key);
+error:
+	return ret;
+}
+
+static void dh_free_data(struct dh *dh)
+{
+	kzfree(dh->key);
+	kzfree(dh->p);
+	kzfree(dh->g);
+}
+
+struct dh_completion {
+	struct completion completion;
+	int err;
+};
+
+static void dh_crypto_done(struct crypto_async_request *req, int err)
+{
+	struct dh_completion *compl = req->data;
+
+	if (err == -EINPROGRESS)
+		return;
+
+	compl->err = err;
+	complete(&compl->completion);
+}
+
+struct kdf_sdesc {
+	struct shash_desc shash;
+	char ctx[];
+};
+
+static int kdf_alloc(struct kdf_sdesc **sdesc_ret, char *hashname)
+{
+	struct crypto_shash *tfm;
+	struct kdf_sdesc *sdesc;
+	int size;
+	int err;
+
+	/* allocate synchronous hash */
+	tfm = crypto_alloc_shash(hashname, 0, 0);
+	if (IS_ERR(tfm)) {
+		pr_info("could not allocate digest TFM handle %s\n", hashname);
+		return PTR_ERR(tfm);
+	}
+
+	err = -EINVAL;
+	if (crypto_shash_digestsize(tfm) == 0)
+		goto out_free_tfm;
+
+	err = -ENOMEM;
+	size = sizeof(struct shash_desc) + crypto_shash_descsize(tfm);
+	sdesc = kmalloc(size, GFP_KERNEL);
+	if (!sdesc)
+		goto out_free_tfm;
+	sdesc->shash.tfm = tfm;
+	sdesc->shash.flags = 0x0;
+
+	*sdesc_ret = sdesc;
+
+	return 0;
+
+out_free_tfm:
+	crypto_free_shash(tfm);
+	return err;
+}
+
+static void kdf_dealloc(struct kdf_sdesc *sdesc)
+{
+	if (!sdesc)
+		return;
+
+	if (sdesc->shash.tfm)
+		crypto_free_shash(sdesc->shash.tfm);
+
+	kzfree(sdesc);
+}
+
+/*
+ * Implementation of the KDF in counter mode according to SP800-108 section 5.1
+ * as well as SP800-56A section 5.8.1 (Single-step KDF).
+ *
+ * SP800-56A:
+ * The src pointer is defined as Z || other info where Z is the shared secret
+ * from DH and other info is an arbitrary string (see SP800-56A section
+ * 5.8.1.2).
+ *
+ * 'dlen' must be a multiple of the digest size.
+ */
+static int kdf_ctr(struct kdf_sdesc *sdesc, const u8 *src, unsigned int slen,
+		   u8 *dst, unsigned int dlen, unsigned int zlen)
+{
+	struct shash_desc *desc = &sdesc->shash;
+	unsigned int h = crypto_shash_digestsize(desc->tfm);
+	int err = 0;
+	u8 *dst_orig = dst;
+	__be32 counter = cpu_to_be32(1);
+
+	while (dlen) {
+		err = crypto_shash_init(desc);
+		if (err)
+			goto err;
+
+		err = crypto_shash_update(desc, (u8 *)&counter, sizeof(__be32));
+		if (err)
+			goto err;
+
+		if (zlen && h) {
+			u8 tmpbuffer[32];
+			size_t chunk = min_t(size_t, zlen, sizeof(tmpbuffer));
+			memset(tmpbuffer, 0, chunk);
+
+			do {
+				err = crypto_shash_update(desc, tmpbuffer,
+							  chunk);
+				if (err)
+					goto err;
+
+				zlen -= chunk;
+				chunk = min_t(size_t, zlen, sizeof(tmpbuffer));
+			} while (zlen);
+		}
+
+		if (src && slen) {
+			err = crypto_shash_update(desc, src, slen);
+			if (err)
+				goto err;
+		}
+
+		err = crypto_shash_final(desc, dst);
+		if (err)
+			goto err;
+
+		dlen -= h;
+		dst += h;
+		counter = cpu_to_be32(be32_to_cpu(counter) + 1);
+	}
+
+	return 0;
+
+err:
+	memzero_explicit(dst_orig, dlen);
+	return err;
+}
+
+static int keyctl_dh_compute_kdf(struct kdf_sdesc *sdesc,
+				 char __user *buffer, size_t buflen,
+				 uint8_t *kbuf, size_t kbuflen, size_t lzero)
+{
+	uint8_t *outbuf = NULL;
+	int ret;
+	size_t outbuf_len = roundup(buflen,
+				    crypto_shash_digestsize(sdesc->shash.tfm));
+
+	outbuf = kmalloc(outbuf_len, GFP_KERNEL);
+	if (!outbuf) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	ret = kdf_ctr(sdesc, kbuf, kbuflen, outbuf, outbuf_len, lzero);
+	if (ret)
+		goto err;
+
+	ret = buflen;
+	if (copy_to_user(buffer, outbuf, buflen) != 0)
+		ret = -EFAULT;
+
+err:
+	kzfree(outbuf);
+	return ret;
+}
+
+long __keyctl_dh_compute(struct keyctl_dh_params __user *params,
+			 char __user *buffer, size_t buflen,
+			 struct keyctl_kdf_params *kdfcopy)
+{
+	long ret;
+	ssize_t dlen;
+	int secretlen;
+	int outlen;
+	struct keyctl_dh_params pcopy;
+	struct dh dh_inputs;
+	struct scatterlist outsg;
+	struct dh_completion compl;
+	struct crypto_kpp *tfm;
+	struct kpp_request *req;
+	uint8_t *secret;
+	uint8_t *outbuf;
+	struct kdf_sdesc *sdesc = NULL;
+
+	if (!params || (!buffer && buflen)) {
+		ret = -EINVAL;
+		goto out1;
+	}
+	if (copy_from_user(&pcopy, params, sizeof(pcopy)) != 0) {
+		ret = -EFAULT;
+		goto out1;
+	}
+
+	if (kdfcopy) {
+		char *hashname;
+
+		if (memchr_inv(kdfcopy->__spare, 0, sizeof(kdfcopy->__spare))) {
+			ret = -EINVAL;
+			goto out1;
+		}
+
+		if (buflen > KEYCTL_KDF_MAX_OUTPUT_LEN ||
+		    kdfcopy->otherinfolen > KEYCTL_KDF_MAX_OI_LEN) {
+			ret = -EMSGSIZE;
+			goto out1;
+		}
+
+		/* get KDF name string */
+		hashname = strndup_user(kdfcopy->hashname, CRYPTO_MAX_ALG_NAME);
+		if (IS_ERR(hashname)) {
+			ret = PTR_ERR(hashname);
+			goto out1;
+		}
+
+		/* allocate KDF from the kernel crypto API */
+		ret = kdf_alloc(&sdesc, hashname);
+		kfree(hashname);
+		if (ret)
+			goto out1;
+	}
+
+	memset(&dh_inputs, 0, sizeof(dh_inputs));
+
+	dlen = dh_data_from_key(pcopy.prime, &dh_inputs.p);
+	if (dlen < 0) {
+		ret = dlen;
+		goto out1;
+	}
+	dh_inputs.p_size = dlen;
+
+	dlen = dh_data_from_key(pcopy.base, &dh_inputs.g);
+	if (dlen < 0) {
+		ret = dlen;
+		goto out2;
+	}
+	dh_inputs.g_size = dlen;
+
+	dlen = dh_data_from_key(pcopy.private, &dh_inputs.key);
+	if (dlen < 0) {
+		ret = dlen;
+		goto out2;
+	}
+	dh_inputs.key_size = dlen;
+
+	secretlen = crypto_dh_key_len(&dh_inputs);
+	secret = kmalloc(secretlen, GFP_KERNEL);
+	if (!secret) {
+		ret = -ENOMEM;
+		goto out2;
+	}
+	ret = crypto_dh_encode_key(secret, secretlen, &dh_inputs);
+	if (ret)
+		goto out3;
+
+	tfm = crypto_alloc_kpp("dh", 0, 0);
+	if (IS_ERR(tfm)) {
+		ret = PTR_ERR(tfm);
+		goto out3;
+	}
+
+	ret = crypto_kpp_set_secret(tfm, secret, secretlen);
+	if (ret)
+		goto out4;
+
+	outlen = crypto_kpp_maxsize(tfm);
+
+	if (!kdfcopy) {
+		/*
+		 * When not using a KDF, buflen 0 is used to read the
+		 * required buffer length
+		 */
+		if (buflen == 0) {
+			ret = outlen;
+			goto out4;
+		} else if (outlen > buflen) {
+			ret = -EOVERFLOW;
+			goto out4;
+		}
+	}
+
+	outbuf = kzalloc(kdfcopy ? (outlen + kdfcopy->otherinfolen) : outlen,
+			 GFP_KERNEL);
+	if (!outbuf) {
+		ret = -ENOMEM;
+		goto out4;
+	}
+
+	sg_init_one(&outsg, outbuf, outlen);
+
+	req = kpp_request_alloc(tfm, GFP_KERNEL);
+	if (!req) {
+		ret = -ENOMEM;
+		goto out5;
+	}
+
+	kpp_request_set_input(req, NULL, 0);
+	kpp_request_set_output(req, &outsg, outlen);
+	init_completion(&compl.completion);
+	kpp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+				 CRYPTO_TFM_REQ_MAY_SLEEP,
+				 dh_crypto_done, &compl);
+
+	/*
+	 * For DH, generate_public_key and generate_shared_secret are
+	 * the same calculation
+	 */
+	ret = crypto_kpp_generate_public_key(req);
+	if (ret == -EINPROGRESS) {
+		wait_for_completion(&compl.completion);
+		ret = compl.err;
+		if (ret)
+			goto out6;
+	}
+
+	if (kdfcopy) {
+		/*
+		 * Concatenate SP800-56A otherinfo past DH shared secret -- the
+		 * input to the KDF is (DH shared secret || otherinfo)
+		 */
+		if (copy_from_user(outbuf + req->dst_len, kdfcopy->otherinfo,
+				   kdfcopy->otherinfolen) != 0) {
+			ret = -EFAULT;
+			goto out6;
+		}
+
+		ret = keyctl_dh_compute_kdf(sdesc, buffer, buflen, outbuf,
+					    req->dst_len + kdfcopy->otherinfolen,
+					    outlen - req->dst_len);
+	} else if (copy_to_user(buffer, outbuf, req->dst_len) == 0) {
+		ret = req->dst_len;
+	} else {
+		ret = -EFAULT;
+	}
+
+out6:
+	kpp_request_free(req);
+out5:
+	kzfree(outbuf);
+out4:
+	crypto_free_kpp(tfm);
+out3:
+	kzfree(secret);
+out2:
+	dh_free_data(&dh_inputs);
+out1:
+	kdf_dealloc(sdesc);
+	return ret;
+}
+
+long keyctl_dh_compute(struct keyctl_dh_params __user *params,
+		       char __user *buffer, size_t buflen,
+		       struct keyctl_kdf_params __user *kdf)
+{
+	struct keyctl_kdf_params kdfcopy;
+
+	if (!kdf)
+		return __keyctl_dh_compute(params, buffer, buflen, NULL);
+
+	if (copy_from_user(&kdfcopy, kdf, sizeof(kdfcopy)) != 0)
+		return -EFAULT;
+
+	return __keyctl_dh_compute(params, buffer, buflen, &kdfcopy);
+}
diff --git a/security/keys/encrypted-keys/Makefile b/security/keys/encrypted-keys/Makefile
new file mode 100644
index 000000000..7a44dce6f
--- /dev/null
+++ b/security/keys/encrypted-keys/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for encrypted keys
+#
+
+obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys.o
+
+encrypted-keys-y := encrypted.o ecryptfs_format.o
+masterkey-$(CONFIG_TRUSTED_KEYS) := masterkey_trusted.o
+masterkey-$(CONFIG_TRUSTED_KEYS)-$(CONFIG_ENCRYPTED_KEYS) := masterkey_trusted.o
+encrypted-keys-y += $(masterkey-y) $(masterkey-m-m)
diff --git a/security/keys/encrypted-keys/ecryptfs_format.c b/security/keys/encrypted-keys/ecryptfs_format.c
new file mode 100644
index 000000000..6daa3b6ff
--- /dev/null
+++ b/security/keys/encrypted-keys/ecryptfs_format.c
@@ -0,0 +1,81 @@
+/*
+ * ecryptfs_format.c: helper functions for the encrypted key type
+ *
+ * Copyright (C) 2006 International Business Machines Corp.
+ * Copyright (C) 2010 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Authors:
+ * Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ * Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ */
+
+#include <linux/module.h>
+#include "ecryptfs_format.h"
+
+u8 *ecryptfs_get_auth_tok_key(struct ecryptfs_auth_tok *auth_tok)
+{
+	return auth_tok->token.password.session_key_encryption_key;
+}
+EXPORT_SYMBOL(ecryptfs_get_auth_tok_key);
+
+/*
+ * ecryptfs_get_versions()
+ *
+ * Source code taken from the software 'ecryptfs-utils' version 83.
+ *
+ */
+void ecryptfs_get_versions(int *major, int *minor, int *file_version)
+{
+	*major = ECRYPTFS_VERSION_MAJOR;
+	*minor = ECRYPTFS_VERSION_MINOR;
+	if (file_version)
+		*file_version = ECRYPTFS_SUPPORTED_FILE_VERSION;
+}
+EXPORT_SYMBOL(ecryptfs_get_versions);
+
+/*
+ * ecryptfs_fill_auth_tok - fill the ecryptfs_auth_tok structure
+ *
+ * Fill the ecryptfs_auth_tok structure with required ecryptfs data.
+ * The source code is inspired to the original function generate_payload()
+ * shipped with the software 'ecryptfs-utils' version 83.
+ *
+ */
+int ecryptfs_fill_auth_tok(struct ecryptfs_auth_tok *auth_tok,
+			   const char *key_desc)
+{
+	int major, minor;
+
+	ecryptfs_get_versions(&major, &minor, NULL);
+	auth_tok->version = (((uint16_t)(major << 8) & 0xFF00)
+			     | ((uint16_t)minor & 0x00FF));
+	auth_tok->token_type = ECRYPTFS_PASSWORD;
+	strncpy((char *)auth_tok->token.password.signature, key_desc,
+		ECRYPTFS_PASSWORD_SIG_SIZE);
+	auth_tok->token.password.session_key_encryption_key_bytes =
+		ECRYPTFS_MAX_KEY_BYTES;
+	/*
+	 * Removed auth_tok->token.password.salt and
+	 * auth_tok->token.password.session_key_encryption_key
+	 * initialization from the original code
+	 */
+	/* TODO: Make the hash parameterizable via policy */
+	auth_tok->token.password.flags |=
+		ECRYPTFS_SESSION_KEY_ENCRYPTION_KEY_SET;
+	/* The kernel code will encrypt the session key. */
+	auth_tok->session_key.encrypted_key[0] = 0;
+	auth_tok->session_key.encrypted_key_size = 0;
+	/* Default; subject to change by kernel eCryptfs */
+	auth_tok->token.password.hash_algo = PGP_DIGEST_ALGO_SHA512;
+	auth_tok->token.password.flags &= ~(ECRYPTFS_PERSISTENT_PASSWORD);
+	return 0;
+}
+EXPORT_SYMBOL(ecryptfs_fill_auth_tok);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/encrypted-keys/ecryptfs_format.h b/security/keys/encrypted-keys/ecryptfs_format.h
new file mode 100644
index 000000000..40294de23
--- /dev/null
+++ b/security/keys/encrypted-keys/ecryptfs_format.h
@@ -0,0 +1,30 @@
+/*
+ * ecryptfs_format.h: helper functions for the encrypted key type
+ *
+ * Copyright (C) 2006 International Business Machines Corp.
+ * Copyright (C) 2010 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Authors:
+ * Michael A. Halcrow <mahalcro@us.ibm.com>
+ * Tyler Hicks <tyhicks@ou.edu>
+ * Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ */
+
+#ifndef __KEYS_ECRYPTFS_H
+#define __KEYS_ECRYPTFS_H
+
+#include <linux/ecryptfs.h>
+
+#define PGP_DIGEST_ALGO_SHA512   10
+
+u8 *ecryptfs_get_auth_tok_key(struct ecryptfs_auth_tok *auth_tok);
+void ecryptfs_get_versions(int *major, int *minor, int *file_version);
+int ecryptfs_fill_auth_tok(struct ecryptfs_auth_tok *auth_tok,
+			   const char *key_desc);
+
+#endif /* __KEYS_ECRYPTFS_H */
diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
new file mode 100644
index 000000000..571f6d486
--- /dev/null
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -0,0 +1,1015 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ * Copyright (C) 2010 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <keys/encrypted-type.h>
+#include <linux/key-type.h>
+#include <linux/random.h>
+#include <linux/rcupdate.h>
+#include <linux/scatterlist.h>
+#include <linux/ctype.h>
+#include <crypto/aes.h>
+#include <crypto/algapi.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <crypto/skcipher.h>
+
+#include "encrypted.h"
+#include "ecryptfs_format.h"
+
+static const char KEY_TRUSTED_PREFIX[] = "trusted:";
+static const char KEY_USER_PREFIX[] = "user:";
+static const char hash_alg[] = "sha256";
+static const char hmac_alg[] = "hmac(sha256)";
+static const char blkcipher_alg[] = "cbc(aes)";
+static const char key_format_default[] = "default";
+static const char key_format_ecryptfs[] = "ecryptfs";
+static unsigned int ivsize;
+static int blksize;
+
+#define KEY_TRUSTED_PREFIX_LEN (sizeof (KEY_TRUSTED_PREFIX) - 1)
+#define KEY_USER_PREFIX_LEN (sizeof (KEY_USER_PREFIX) - 1)
+#define KEY_ECRYPTFS_DESC_LEN 16
+#define HASH_SIZE SHA256_DIGEST_SIZE
+#define MAX_DATA_SIZE 4096
+#define MIN_DATA_SIZE  20
+
+static struct crypto_shash *hash_tfm;
+
+enum {
+	Opt_err = -1, Opt_new, Opt_load, Opt_update
+};
+
+enum {
+	Opt_error = -1, Opt_default, Opt_ecryptfs
+};
+
+static const match_table_t key_format_tokens = {
+	{Opt_default, "default"},
+	{Opt_ecryptfs, "ecryptfs"},
+	{Opt_error, NULL}
+};
+
+static const match_table_t key_tokens = {
+	{Opt_new, "new"},
+	{Opt_load, "load"},
+	{Opt_update, "update"},
+	{Opt_err, NULL}
+};
+
+static int aes_get_sizes(void)
+{
+	struct crypto_skcipher *tfm;
+
+	tfm = crypto_alloc_skcipher(blkcipher_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm)) {
+		pr_err("encrypted_key: failed to alloc_cipher (%ld)\n",
+		       PTR_ERR(tfm));
+		return PTR_ERR(tfm);
+	}
+	ivsize = crypto_skcipher_ivsize(tfm);
+	blksize = crypto_skcipher_blocksize(tfm);
+	crypto_free_skcipher(tfm);
+	return 0;
+}
+
+/*
+ * valid_ecryptfs_desc - verify the description of a new/loaded encrypted key
+ *
+ * The description of a encrypted key with format 'ecryptfs' must contain
+ * exactly 16 hexadecimal characters.
+ *
+ */
+static int valid_ecryptfs_desc(const char *ecryptfs_desc)
+{
+	int i;
+
+	if (strlen(ecryptfs_desc) != KEY_ECRYPTFS_DESC_LEN) {
+		pr_err("encrypted_key: key description must be %d hexadecimal "
+		       "characters long\n", KEY_ECRYPTFS_DESC_LEN);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < KEY_ECRYPTFS_DESC_LEN; i++) {
+		if (!isxdigit(ecryptfs_desc[i])) {
+			pr_err("encrypted_key: key description must contain "
+			       "only hexadecimal characters\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * valid_master_desc - verify the 'key-type:desc' of a new/updated master-key
+ *
+ * key-type:= "trusted:" | "user:"
+ * desc:= master-key description
+ *
+ * Verify that 'key-type' is valid and that 'desc' exists. On key update,
+ * only the master key description is permitted to change, not the key-type.
+ * The key-type remains constant.
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int valid_master_desc(const char *new_desc, const char *orig_desc)
+{
+	int prefix_len;
+
+	if (!strncmp(new_desc, KEY_TRUSTED_PREFIX, KEY_TRUSTED_PREFIX_LEN))
+		prefix_len = KEY_TRUSTED_PREFIX_LEN;
+	else if (!strncmp(new_desc, KEY_USER_PREFIX, KEY_USER_PREFIX_LEN))
+		prefix_len = KEY_USER_PREFIX_LEN;
+	else
+		return -EINVAL;
+
+	if (!new_desc[prefix_len])
+		return -EINVAL;
+
+	if (orig_desc && strncmp(new_desc, orig_desc, prefix_len))
+		return -EINVAL;
+
+	return 0;
+}
+
+/*
+ * datablob_parse - parse the keyctl data
+ *
+ * datablob format:
+ * new [<format>] <master-key name> <decrypted data length>
+ * load [<format>] <master-key name> <decrypted data length>
+ *     <encrypted iv + data>
+ * update <new-master-key name>
+ *
+ * Tokenizes a copy of the keyctl data, returning a pointer to each token,
+ * which is null terminated.
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, const char **format,
+			  char **master_desc, char **decrypted_datalen,
+			  char **hex_encoded_iv)
+{
+	substring_t args[MAX_OPT_ARGS];
+	int ret = -EINVAL;
+	int key_cmd;
+	int key_format;
+	char *p, *keyword;
+
+	keyword = strsep(&datablob, " \t");
+	if (!keyword) {
+		pr_info("encrypted_key: insufficient parameters specified\n");
+		return ret;
+	}
+	key_cmd = match_token(keyword, key_tokens, args);
+
+	/* Get optional format: default | ecryptfs */
+	p = strsep(&datablob, " \t");
+	if (!p) {
+		pr_err("encrypted_key: insufficient parameters specified\n");
+		return ret;
+	}
+
+	key_format = match_token(p, key_format_tokens, args);
+	switch (key_format) {
+	case Opt_ecryptfs:
+	case Opt_default:
+		*format = p;
+		*master_desc = strsep(&datablob, " \t");
+		break;
+	case Opt_error:
+		*master_desc = p;
+		break;
+	}
+
+	if (!*master_desc) {
+		pr_info("encrypted_key: master key parameter is missing\n");
+		goto out;
+	}
+
+	if (valid_master_desc(*master_desc, NULL) < 0) {
+		pr_info("encrypted_key: master key parameter \'%s\' "
+			"is invalid\n", *master_desc);
+		goto out;
+	}
+
+	if (decrypted_datalen) {
+		*decrypted_datalen = strsep(&datablob, " \t");
+		if (!*decrypted_datalen) {
+			pr_info("encrypted_key: keylen parameter is missing\n");
+			goto out;
+		}
+	}
+
+	switch (key_cmd) {
+	case Opt_new:
+		if (!decrypted_datalen) {
+			pr_info("encrypted_key: keyword \'%s\' not allowed "
+				"when called from .update method\n", keyword);
+			break;
+		}
+		ret = 0;
+		break;
+	case Opt_load:
+		if (!decrypted_datalen) {
+			pr_info("encrypted_key: keyword \'%s\' not allowed "
+				"when called from .update method\n", keyword);
+			break;
+		}
+		*hex_encoded_iv = strsep(&datablob, " \t");
+		if (!*hex_encoded_iv) {
+			pr_info("encrypted_key: hex blob is missing\n");
+			break;
+		}
+		ret = 0;
+		break;
+	case Opt_update:
+		if (decrypted_datalen) {
+			pr_info("encrypted_key: keyword \'%s\' not allowed "
+				"when called from .instantiate method\n",
+				keyword);
+			break;
+		}
+		ret = 0;
+		break;
+	case Opt_err:
+		pr_info("encrypted_key: keyword \'%s\' not recognized\n",
+			keyword);
+		break;
+	}
+out:
+	return ret;
+}
+
+/*
+ * datablob_format - format as an ascii string, before copying to userspace
+ */
+static char *datablob_format(struct encrypted_key_payload *epayload,
+			     size_t asciiblob_len)
+{
+	char *ascii_buf, *bufp;
+	u8 *iv = epayload->iv;
+	int len;
+	int i;
+
+	ascii_buf = kmalloc(asciiblob_len + 1, GFP_KERNEL);
+	if (!ascii_buf)
+		goto out;
+
+	ascii_buf[asciiblob_len] = '\0';
+
+	/* copy datablob master_desc and datalen strings */
+	len = sprintf(ascii_buf, "%s %s %s ", epayload->format,
+		      epayload->master_desc, epayload->datalen);
+
+	/* convert the hex encoded iv, encrypted-data and HMAC to ascii */
+	bufp = &ascii_buf[len];
+	for (i = 0; i < (asciiblob_len - len) / 2; i++)
+		bufp = hex_byte_pack(bufp, iv[i]);
+out:
+	return ascii_buf;
+}
+
+/*
+ * request_user_key - request the user key
+ *
+ * Use a user provided key to encrypt/decrypt an encrypted-key.
+ */
+static struct key *request_user_key(const char *master_desc, const u8 **master_key,
+				    size_t *master_keylen)
+{
+	const struct user_key_payload *upayload;
+	struct key *ukey;
+
+	ukey = request_key(&key_type_user, master_desc, NULL);
+	if (IS_ERR(ukey))
+		goto error;
+
+	down_read(&ukey->sem);
+	upayload = user_key_payload_locked(ukey);
+	if (!upayload) {
+		/* key was revoked before we acquired its semaphore */
+		up_read(&ukey->sem);
+		key_put(ukey);
+		ukey = ERR_PTR(-EKEYREVOKED);
+		goto error;
+	}
+	*master_key = upayload->data;
+	*master_keylen = upayload->datalen;
+error:
+	return ukey;
+}
+
+static int calc_hash(struct crypto_shash *tfm, u8 *digest,
+		     const u8 *buf, unsigned int buflen)
+{
+	SHASH_DESC_ON_STACK(desc, tfm);
+	int err;
+
+	desc->tfm = tfm;
+	desc->flags = 0;
+
+	err = crypto_shash_digest(desc, buf, buflen, digest);
+	shash_desc_zero(desc);
+	return err;
+}
+
+static int calc_hmac(u8 *digest, const u8 *key, unsigned int keylen,
+		     const u8 *buf, unsigned int buflen)
+{
+	struct crypto_shash *tfm;
+	int err;
+
+	tfm = crypto_alloc_shash(hmac_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm)) {
+		pr_err("encrypted_key: can't alloc %s transform: %ld\n",
+		       hmac_alg, PTR_ERR(tfm));
+		return PTR_ERR(tfm);
+	}
+
+	err = crypto_shash_setkey(tfm, key, keylen);
+	if (!err)
+		err = calc_hash(tfm, digest, buf, buflen);
+	crypto_free_shash(tfm);
+	return err;
+}
+
+enum derived_key_type { ENC_KEY, AUTH_KEY };
+
+/* Derive authentication/encryption key from trusted key */
+static int get_derived_key(u8 *derived_key, enum derived_key_type key_type,
+			   const u8 *master_key, size_t master_keylen)
+{
+	u8 *derived_buf;
+	unsigned int derived_buf_len;
+	int ret;
+
+	derived_buf_len = strlen("AUTH_KEY") + 1 + master_keylen;
+	if (derived_buf_len < HASH_SIZE)
+		derived_buf_len = HASH_SIZE;
+
+	derived_buf = kzalloc(derived_buf_len, GFP_KERNEL);
+	if (!derived_buf)
+		return -ENOMEM;
+
+	if (key_type)
+		strcpy(derived_buf, "AUTH_KEY");
+	else
+		strcpy(derived_buf, "ENC_KEY");
+
+	memcpy(derived_buf + strlen(derived_buf) + 1, master_key,
+	       master_keylen);
+	ret = calc_hash(hash_tfm, derived_key, derived_buf, derived_buf_len);
+	kzfree(derived_buf);
+	return ret;
+}
+
+static struct skcipher_request *init_skcipher_req(const u8 *key,
+						  unsigned int key_len)
+{
+	struct skcipher_request *req;
+	struct crypto_skcipher *tfm;
+	int ret;
+
+	tfm = crypto_alloc_skcipher(blkcipher_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(tfm)) {
+		pr_err("encrypted_key: failed to load %s transform (%ld)\n",
+		       blkcipher_alg, PTR_ERR(tfm));
+		return ERR_CAST(tfm);
+	}
+
+	ret = crypto_skcipher_setkey(tfm, key, key_len);
+	if (ret < 0) {
+		pr_err("encrypted_key: failed to setkey (%d)\n", ret);
+		crypto_free_skcipher(tfm);
+		return ERR_PTR(ret);
+	}
+
+	req = skcipher_request_alloc(tfm, GFP_KERNEL);
+	if (!req) {
+		pr_err("encrypted_key: failed to allocate request for %s\n",
+		       blkcipher_alg);
+		crypto_free_skcipher(tfm);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	return req;
+}
+
+static struct key *request_master_key(struct encrypted_key_payload *epayload,
+				      const u8 **master_key, size_t *master_keylen)
+{
+	struct key *mkey = ERR_PTR(-EINVAL);
+
+	if (!strncmp(epayload->master_desc, KEY_TRUSTED_PREFIX,
+		     KEY_TRUSTED_PREFIX_LEN)) {
+		mkey = request_trusted_key(epayload->master_desc +
+					   KEY_TRUSTED_PREFIX_LEN,
+					   master_key, master_keylen);
+	} else if (!strncmp(epayload->master_desc, KEY_USER_PREFIX,
+			    KEY_USER_PREFIX_LEN)) {
+		mkey = request_user_key(epayload->master_desc +
+					KEY_USER_PREFIX_LEN,
+					master_key, master_keylen);
+	} else
+		goto out;
+
+	if (IS_ERR(mkey)) {
+		int ret = PTR_ERR(mkey);
+
+		if (ret == -ENOTSUPP)
+			pr_info("encrypted_key: key %s not supported",
+				epayload->master_desc);
+		else
+			pr_info("encrypted_key: key %s not found",
+				epayload->master_desc);
+		goto out;
+	}
+
+	dump_master_key(*master_key, *master_keylen);
+out:
+	return mkey;
+}
+
+/* Before returning data to userspace, encrypt decrypted data. */
+static int derived_key_encrypt(struct encrypted_key_payload *epayload,
+			       const u8 *derived_key,
+			       unsigned int derived_keylen)
+{
+	struct scatterlist sg_in[2];
+	struct scatterlist sg_out[1];
+	struct crypto_skcipher *tfm;
+	struct skcipher_request *req;
+	unsigned int encrypted_datalen;
+	u8 iv[AES_BLOCK_SIZE];
+	int ret;
+
+	encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+
+	req = init_skcipher_req(derived_key, derived_keylen);
+	ret = PTR_ERR(req);
+	if (IS_ERR(req))
+		goto out;
+	dump_decrypted_data(epayload);
+
+	sg_init_table(sg_in, 2);
+	sg_set_buf(&sg_in[0], epayload->decrypted_data,
+		   epayload->decrypted_datalen);
+	sg_set_page(&sg_in[1], ZERO_PAGE(0), AES_BLOCK_SIZE, 0);
+
+	sg_init_table(sg_out, 1);
+	sg_set_buf(sg_out, epayload->encrypted_data, encrypted_datalen);
+
+	memcpy(iv, epayload->iv, sizeof(iv));
+	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen, iv);
+	ret = crypto_skcipher_encrypt(req);
+	tfm = crypto_skcipher_reqtfm(req);
+	skcipher_request_free(req);
+	crypto_free_skcipher(tfm);
+	if (ret < 0)
+		pr_err("encrypted_key: failed to encrypt (%d)\n", ret);
+	else
+		dump_encrypted_data(epayload, encrypted_datalen);
+out:
+	return ret;
+}
+
+static int datablob_hmac_append(struct encrypted_key_payload *epayload,
+				const u8 *master_key, size_t master_keylen)
+{
+	u8 derived_key[HASH_SIZE];
+	u8 *digest;
+	int ret;
+
+	ret = get_derived_key(derived_key, AUTH_KEY, master_key, master_keylen);
+	if (ret < 0)
+		goto out;
+
+	digest = epayload->format + epayload->datablob_len;
+	ret = calc_hmac(digest, derived_key, sizeof derived_key,
+			epayload->format, epayload->datablob_len);
+	if (!ret)
+		dump_hmac(NULL, digest, HASH_SIZE);
+out:
+	memzero_explicit(derived_key, sizeof(derived_key));
+	return ret;
+}
+
+/* verify HMAC before decrypting encrypted key */
+static int datablob_hmac_verify(struct encrypted_key_payload *epayload,
+				const u8 *format, const u8 *master_key,
+				size_t master_keylen)
+{
+	u8 derived_key[HASH_SIZE];
+	u8 digest[HASH_SIZE];
+	int ret;
+	char *p;
+	unsigned short len;
+
+	ret = get_derived_key(derived_key, AUTH_KEY, master_key, master_keylen);
+	if (ret < 0)
+		goto out;
+
+	len = epayload->datablob_len;
+	if (!format) {
+		p = epayload->master_desc;
+		len -= strlen(epayload->format) + 1;
+	} else
+		p = epayload->format;
+
+	ret = calc_hmac(digest, derived_key, sizeof derived_key, p, len);
+	if (ret < 0)
+		goto out;
+	ret = crypto_memneq(digest, epayload->format + epayload->datablob_len,
+			    sizeof(digest));
+	if (ret) {
+		ret = -EINVAL;
+		dump_hmac("datablob",
+			  epayload->format + epayload->datablob_len,
+			  HASH_SIZE);
+		dump_hmac("calc", digest, HASH_SIZE);
+	}
+out:
+	memzero_explicit(derived_key, sizeof(derived_key));
+	return ret;
+}
+
+static int derived_key_decrypt(struct encrypted_key_payload *epayload,
+			       const u8 *derived_key,
+			       unsigned int derived_keylen)
+{
+	struct scatterlist sg_in[1];
+	struct scatterlist sg_out[2];
+	struct crypto_skcipher *tfm;
+	struct skcipher_request *req;
+	unsigned int encrypted_datalen;
+	u8 iv[AES_BLOCK_SIZE];
+	u8 *pad;
+	int ret;
+
+	/* Throwaway buffer to hold the unused zero padding at the end */
+	pad = kmalloc(AES_BLOCK_SIZE, GFP_KERNEL);
+	if (!pad)
+		return -ENOMEM;
+
+	encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+	req = init_skcipher_req(derived_key, derived_keylen);
+	ret = PTR_ERR(req);
+	if (IS_ERR(req))
+		goto out;
+	dump_encrypted_data(epayload, encrypted_datalen);
+
+	sg_init_table(sg_in, 1);
+	sg_init_table(sg_out, 2);
+	sg_set_buf(sg_in, epayload->encrypted_data, encrypted_datalen);
+	sg_set_buf(&sg_out[0], epayload->decrypted_data,
+		   epayload->decrypted_datalen);
+	sg_set_buf(&sg_out[1], pad, AES_BLOCK_SIZE);
+
+	memcpy(iv, epayload->iv, sizeof(iv));
+	skcipher_request_set_crypt(req, sg_in, sg_out, encrypted_datalen, iv);
+	ret = crypto_skcipher_decrypt(req);
+	tfm = crypto_skcipher_reqtfm(req);
+	skcipher_request_free(req);
+	crypto_free_skcipher(tfm);
+	if (ret < 0)
+		goto out;
+	dump_decrypted_data(epayload);
+out:
+	kfree(pad);
+	return ret;
+}
+
+/* Allocate memory for decrypted key and datablob. */
+static struct encrypted_key_payload *encrypted_key_alloc(struct key *key,
+							 const char *format,
+							 const char *master_desc,
+							 const char *datalen)
+{
+	struct encrypted_key_payload *epayload = NULL;
+	unsigned short datablob_len;
+	unsigned short decrypted_datalen;
+	unsigned short payload_datalen;
+	unsigned int encrypted_datalen;
+	unsigned int format_len;
+	long dlen;
+	int ret;
+
+	ret = kstrtol(datalen, 10, &dlen);
+	if (ret < 0 || dlen < MIN_DATA_SIZE || dlen > MAX_DATA_SIZE)
+		return ERR_PTR(-EINVAL);
+
+	format_len = (!format) ? strlen(key_format_default) : strlen(format);
+	decrypted_datalen = dlen;
+	payload_datalen = decrypted_datalen;
+	if (format && !strcmp(format, key_format_ecryptfs)) {
+		if (dlen != ECRYPTFS_MAX_KEY_BYTES) {
+			pr_err("encrypted_key: keylen for the ecryptfs format "
+			       "must be equal to %d bytes\n",
+			       ECRYPTFS_MAX_KEY_BYTES);
+			return ERR_PTR(-EINVAL);
+		}
+		decrypted_datalen = ECRYPTFS_MAX_KEY_BYTES;
+		payload_datalen = sizeof(struct ecryptfs_auth_tok);
+	}
+
+	encrypted_datalen = roundup(decrypted_datalen, blksize);
+
+	datablob_len = format_len + 1 + strlen(master_desc) + 1
+	    + strlen(datalen) + 1 + ivsize + 1 + encrypted_datalen;
+
+	ret = key_payload_reserve(key, payload_datalen + datablob_len
+				  + HASH_SIZE + 1);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	epayload = kzalloc(sizeof(*epayload) + payload_datalen +
+			   datablob_len + HASH_SIZE + 1, GFP_KERNEL);
+	if (!epayload)
+		return ERR_PTR(-ENOMEM);
+
+	epayload->payload_datalen = payload_datalen;
+	epayload->decrypted_datalen = decrypted_datalen;
+	epayload->datablob_len = datablob_len;
+	return epayload;
+}
+
+static int encrypted_key_decrypt(struct encrypted_key_payload *epayload,
+				 const char *format, const char *hex_encoded_iv)
+{
+	struct key *mkey;
+	u8 derived_key[HASH_SIZE];
+	const u8 *master_key;
+	u8 *hmac;
+	const char *hex_encoded_data;
+	unsigned int encrypted_datalen;
+	size_t master_keylen;
+	size_t asciilen;
+	int ret;
+
+	encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+	asciilen = (ivsize + 1 + encrypted_datalen + HASH_SIZE) * 2;
+	if (strlen(hex_encoded_iv) != asciilen)
+		return -EINVAL;
+
+	hex_encoded_data = hex_encoded_iv + (2 * ivsize) + 2;
+	ret = hex2bin(epayload->iv, hex_encoded_iv, ivsize);
+	if (ret < 0)
+		return -EINVAL;
+	ret = hex2bin(epayload->encrypted_data, hex_encoded_data,
+		      encrypted_datalen);
+	if (ret < 0)
+		return -EINVAL;
+
+	hmac = epayload->format + epayload->datablob_len;
+	ret = hex2bin(hmac, hex_encoded_data + (encrypted_datalen * 2),
+		      HASH_SIZE);
+	if (ret < 0)
+		return -EINVAL;
+
+	mkey = request_master_key(epayload, &master_key, &master_keylen);
+	if (IS_ERR(mkey))
+		return PTR_ERR(mkey);
+
+	ret = datablob_hmac_verify(epayload, format, master_key, master_keylen);
+	if (ret < 0) {
+		pr_err("encrypted_key: bad hmac (%d)\n", ret);
+		goto out;
+	}
+
+	ret = get_derived_key(derived_key, ENC_KEY, master_key, master_keylen);
+	if (ret < 0)
+		goto out;
+
+	ret = derived_key_decrypt(epayload, derived_key, sizeof derived_key);
+	if (ret < 0)
+		pr_err("encrypted_key: failed to decrypt key (%d)\n", ret);
+out:
+	up_read(&mkey->sem);
+	key_put(mkey);
+	memzero_explicit(derived_key, sizeof(derived_key));
+	return ret;
+}
+
+static void __ekey_init(struct encrypted_key_payload *epayload,
+			const char *format, const char *master_desc,
+			const char *datalen)
+{
+	unsigned int format_len;
+
+	format_len = (!format) ? strlen(key_format_default) : strlen(format);
+	epayload->format = epayload->payload_data + epayload->payload_datalen;
+	epayload->master_desc = epayload->format + format_len + 1;
+	epayload->datalen = epayload->master_desc + strlen(master_desc) + 1;
+	epayload->iv = epayload->datalen + strlen(datalen) + 1;
+	epayload->encrypted_data = epayload->iv + ivsize + 1;
+	epayload->decrypted_data = epayload->payload_data;
+
+	if (!format)
+		memcpy(epayload->format, key_format_default, format_len);
+	else {
+		if (!strcmp(format, key_format_ecryptfs))
+			epayload->decrypted_data =
+				ecryptfs_get_auth_tok_key((struct ecryptfs_auth_tok *)epayload->payload_data);
+
+		memcpy(epayload->format, format, format_len);
+	}
+
+	memcpy(epayload->master_desc, master_desc, strlen(master_desc));
+	memcpy(epayload->datalen, datalen, strlen(datalen));
+}
+
+/*
+ * encrypted_init - initialize an encrypted key
+ *
+ * For a new key, use a random number for both the iv and data
+ * itself.  For an old key, decrypt the hex encoded data.
+ */
+static int encrypted_init(struct encrypted_key_payload *epayload,
+			  const char *key_desc, const char *format,
+			  const char *master_desc, const char *datalen,
+			  const char *hex_encoded_iv)
+{
+	int ret = 0;
+
+	if (format && !strcmp(format, key_format_ecryptfs)) {
+		ret = valid_ecryptfs_desc(key_desc);
+		if (ret < 0)
+			return ret;
+
+		ecryptfs_fill_auth_tok((struct ecryptfs_auth_tok *)epayload->payload_data,
+				       key_desc);
+	}
+
+	__ekey_init(epayload, format, master_desc, datalen);
+	if (!hex_encoded_iv) {
+		get_random_bytes(epayload->iv, ivsize);
+
+		get_random_bytes(epayload->decrypted_data,
+				 epayload->decrypted_datalen);
+	} else
+		ret = encrypted_key_decrypt(epayload, format, hex_encoded_iv);
+	return ret;
+}
+
+/*
+ * encrypted_instantiate - instantiate an encrypted key
+ *
+ * Decrypt an existing encrypted datablob or create a new encrypted key
+ * based on a kernel random number.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int encrypted_instantiate(struct key *key,
+				 struct key_preparsed_payload *prep)
+{
+	struct encrypted_key_payload *epayload = NULL;
+	char *datablob = NULL;
+	const char *format = NULL;
+	char *master_desc = NULL;
+	char *decrypted_datalen = NULL;
+	char *hex_encoded_iv = NULL;
+	size_t datalen = prep->datalen;
+	int ret;
+
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	datablob = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!datablob)
+		return -ENOMEM;
+	datablob[datalen] = 0;
+	memcpy(datablob, prep->data, datalen);
+	ret = datablob_parse(datablob, &format, &master_desc,
+			     &decrypted_datalen, &hex_encoded_iv);
+	if (ret < 0)
+		goto out;
+
+	epayload = encrypted_key_alloc(key, format, master_desc,
+				       decrypted_datalen);
+	if (IS_ERR(epayload)) {
+		ret = PTR_ERR(epayload);
+		goto out;
+	}
+	ret = encrypted_init(epayload, key->description, format, master_desc,
+			     decrypted_datalen, hex_encoded_iv);
+	if (ret < 0) {
+		kzfree(epayload);
+		goto out;
+	}
+
+	rcu_assign_keypointer(key, epayload);
+out:
+	kzfree(datablob);
+	return ret;
+}
+
+static void encrypted_rcu_free(struct rcu_head *rcu)
+{
+	struct encrypted_key_payload *epayload;
+
+	epayload = container_of(rcu, struct encrypted_key_payload, rcu);
+	kzfree(epayload);
+}
+
+/*
+ * encrypted_update - update the master key description
+ *
+ * Change the master key description for an existing encrypted key.
+ * The next read will return an encrypted datablob using the new
+ * master key description.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int encrypted_update(struct key *key, struct key_preparsed_payload *prep)
+{
+	struct encrypted_key_payload *epayload = key->payload.data[0];
+	struct encrypted_key_payload *new_epayload;
+	char *buf;
+	char *new_master_desc = NULL;
+	const char *format = NULL;
+	size_t datalen = prep->datalen;
+	int ret = 0;
+
+	if (key_is_negative(key))
+		return -ENOKEY;
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	buf = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	buf[datalen] = 0;
+	memcpy(buf, prep->data, datalen);
+	ret = datablob_parse(buf, &format, &new_master_desc, NULL, NULL);
+	if (ret < 0)
+		goto out;
+
+	ret = valid_master_desc(new_master_desc, epayload->master_desc);
+	if (ret < 0)
+		goto out;
+
+	new_epayload = encrypted_key_alloc(key, epayload->format,
+					   new_master_desc, epayload->datalen);
+	if (IS_ERR(new_epayload)) {
+		ret = PTR_ERR(new_epayload);
+		goto out;
+	}
+
+	__ekey_init(new_epayload, epayload->format, new_master_desc,
+		    epayload->datalen);
+
+	memcpy(new_epayload->iv, epayload->iv, ivsize);
+	memcpy(new_epayload->payload_data, epayload->payload_data,
+	       epayload->payload_datalen);
+
+	rcu_assign_keypointer(key, new_epayload);
+	call_rcu(&epayload->rcu, encrypted_rcu_free);
+out:
+	kzfree(buf);
+	return ret;
+}
+
+/*
+ * encrypted_read - format and copy out the encrypted data
+ *
+ * The resulting datablob format is:
+ * <master-key name> <decrypted data length> <encrypted iv> <encrypted data>
+ *
+ * On success, return to userspace the encrypted key datablob size.
+ */
+static long encrypted_read(const struct key *key, char *buffer,
+			   size_t buflen)
+{
+	struct encrypted_key_payload *epayload;
+	struct key *mkey;
+	const u8 *master_key;
+	size_t master_keylen;
+	char derived_key[HASH_SIZE];
+	char *ascii_buf;
+	size_t asciiblob_len;
+	int ret;
+
+	epayload = dereference_key_locked(key);
+
+	/* returns the hex encoded iv, encrypted-data, and hmac as ascii */
+	asciiblob_len = epayload->datablob_len + ivsize + 1
+	    + roundup(epayload->decrypted_datalen, blksize)
+	    + (HASH_SIZE * 2);
+
+	if (!buffer || buflen < asciiblob_len)
+		return asciiblob_len;
+
+	mkey = request_master_key(epayload, &master_key, &master_keylen);
+	if (IS_ERR(mkey))
+		return PTR_ERR(mkey);
+
+	ret = get_derived_key(derived_key, ENC_KEY, master_key, master_keylen);
+	if (ret < 0)
+		goto out;
+
+	ret = derived_key_encrypt(epayload, derived_key, sizeof derived_key);
+	if (ret < 0)
+		goto out;
+
+	ret = datablob_hmac_append(epayload, master_key, master_keylen);
+	if (ret < 0)
+		goto out;
+
+	ascii_buf = datablob_format(epayload, asciiblob_len);
+	if (!ascii_buf) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	up_read(&mkey->sem);
+	key_put(mkey);
+	memzero_explicit(derived_key, sizeof(derived_key));
+
+	memcpy(buffer, ascii_buf, asciiblob_len);
+	kzfree(ascii_buf);
+
+	return asciiblob_len;
+out:
+	up_read(&mkey->sem);
+	key_put(mkey);
+	memzero_explicit(derived_key, sizeof(derived_key));
+	return ret;
+}
+
+/*
+ * encrypted_destroy - clear and free the key's payload
+ */
+static void encrypted_destroy(struct key *key)
+{
+	kzfree(key->payload.data[0]);
+}
+
+struct key_type key_type_encrypted = {
+	.name = "encrypted",
+	.instantiate = encrypted_instantiate,
+	.update = encrypted_update,
+	.destroy = encrypted_destroy,
+	.describe = user_describe,
+	.read = encrypted_read,
+};
+EXPORT_SYMBOL_GPL(key_type_encrypted);
+
+static int __init init_encrypted(void)
+{
+	int ret;
+
+	hash_tfm = crypto_alloc_shash(hash_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(hash_tfm)) {
+		pr_err("encrypted_key: can't allocate %s transform: %ld\n",
+		       hash_alg, PTR_ERR(hash_tfm));
+		return PTR_ERR(hash_tfm);
+	}
+
+	ret = aes_get_sizes();
+	if (ret < 0)
+		goto out;
+	ret = register_key_type(&key_type_encrypted);
+	if (ret < 0)
+		goto out;
+	return 0;
+out:
+	crypto_free_shash(hash_tfm);
+	return ret;
+
+}
+
+static void __exit cleanup_encrypted(void)
+{
+	crypto_free_shash(hash_tfm);
+	unregister_key_type(&key_type_encrypted);
+}
+
+late_initcall(init_encrypted);
+module_exit(cleanup_encrypted);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/encrypted-keys/encrypted.h b/security/keys/encrypted-keys/encrypted.h
new file mode 100644
index 000000000..1809995db
--- /dev/null
+++ b/security/keys/encrypted-keys/encrypted.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ENCRYPTED_KEY_H
+#define __ENCRYPTED_KEY_H
+
+#define ENCRYPTED_DEBUG 0
+#if defined(CONFIG_TRUSTED_KEYS) || \
+  (defined(CONFIG_TRUSTED_KEYS_MODULE) && defined(CONFIG_ENCRYPTED_KEYS_MODULE))
+extern struct key *request_trusted_key(const char *trusted_desc,
+				       const u8 **master_key, size_t *master_keylen);
+#else
+static inline struct key *request_trusted_key(const char *trusted_desc,
+					      const u8 **master_key,
+					      size_t *master_keylen)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+#endif
+
+#if ENCRYPTED_DEBUG
+static inline void dump_master_key(const u8 *master_key, size_t master_keylen)
+{
+	print_hex_dump(KERN_ERR, "master key: ", DUMP_PREFIX_NONE, 32, 1,
+		       master_key, master_keylen, 0);
+}
+
+static inline void dump_decrypted_data(struct encrypted_key_payload *epayload)
+{
+	print_hex_dump(KERN_ERR, "decrypted data: ", DUMP_PREFIX_NONE, 32, 1,
+		       epayload->decrypted_data,
+		       epayload->decrypted_datalen, 0);
+}
+
+static inline void dump_encrypted_data(struct encrypted_key_payload *epayload,
+				       unsigned int encrypted_datalen)
+{
+	print_hex_dump(KERN_ERR, "encrypted data: ", DUMP_PREFIX_NONE, 32, 1,
+		       epayload->encrypted_data, encrypted_datalen, 0);
+}
+
+static inline void dump_hmac(const char *str, const u8 *digest,
+			     unsigned int hmac_size)
+{
+	if (str)
+		pr_info("encrypted_key: %s", str);
+	print_hex_dump(KERN_ERR, "hmac: ", DUMP_PREFIX_NONE, 32, 1, digest,
+		       hmac_size, 0);
+}
+#else
+static inline void dump_master_key(const u8 *master_key, size_t master_keylen)
+{
+}
+
+static inline void dump_decrypted_data(struct encrypted_key_payload *epayload)
+{
+}
+
+static inline void dump_encrypted_data(struct encrypted_key_payload *epayload,
+				       unsigned int encrypted_datalen)
+{
+}
+
+static inline void dump_hmac(const char *str, const u8 *digest,
+			     unsigned int hmac_size)
+{
+}
+#endif
+#endif
diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c
new file mode 100644
index 000000000..cbf0bc127
--- /dev/null
+++ b/security/keys/encrypted-keys/masterkey_trusted.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ * Copyright (C) 2010 Politecnico di Torino, Italy
+ *                    TORSEC group -- http://security.polito.it
+ *
+ * Authors:
+ * Mimi Zohar <zohar@us.ibm.com>
+ * Roberto Sassu <roberto.sassu@polito.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <keys/trusted-type.h>
+#include <keys/encrypted-type.h>
+#include "encrypted.h"
+
+/*
+ * request_trusted_key - request the trusted key
+ *
+ * Trusted keys are sealed to PCRs and other metadata. Although userspace
+ * manages both trusted/encrypted key-types, like the encrypted key type
+ * data, trusted key type data is not visible decrypted from userspace.
+ */
+struct key *request_trusted_key(const char *trusted_desc,
+				const u8 **master_key, size_t *master_keylen)
+{
+	struct trusted_key_payload *tpayload;
+	struct key *tkey;
+
+	tkey = request_key(&key_type_trusted, trusted_desc, NULL);
+	if (IS_ERR(tkey))
+		goto error;
+
+	down_read(&tkey->sem);
+	tpayload = tkey->payload.data[0];
+	*master_key = tpayload->key;
+	*master_keylen = tpayload->key_len;
+error:
+	return tkey;
+}
diff --git a/security/keys/gc.c b/security/keys/gc.c
new file mode 100644
index 000000000..7207e6094
--- /dev/null
+++ b/security/keys/gc.c
@@ -0,0 +1,369 @@
+/* Key garbage collector
+ *
+ * Copyright (C) 2009-2011 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <keys/keyring-type.h>
+#include "internal.h"
+
+/*
+ * Delay between key revocation/expiry in seconds
+ */
+unsigned key_gc_delay = 5 * 60;
+
+/*
+ * Reaper for unused keys.
+ */
+static void key_garbage_collector(struct work_struct *work);
+DECLARE_WORK(key_gc_work, key_garbage_collector);
+
+/*
+ * Reaper for links from keyrings to dead keys.
+ */
+static void key_gc_timer_func(struct timer_list *);
+static DEFINE_TIMER(key_gc_timer, key_gc_timer_func);
+
+static time64_t key_gc_next_run = TIME64_MAX;
+static struct key_type *key_gc_dead_keytype;
+
+static unsigned long key_gc_flags;
+#define KEY_GC_KEY_EXPIRED	0	/* A key expired and needs unlinking */
+#define KEY_GC_REAP_KEYTYPE	1	/* A keytype is being unregistered */
+#define KEY_GC_REAPING_KEYTYPE	2	/* Cleared when keytype reaped */
+
+
+/*
+ * Any key whose type gets unregistered will be re-typed to this if it can't be
+ * immediately unlinked.
+ */
+struct key_type key_type_dead = {
+	.name = ".dead",
+};
+
+/*
+ * Schedule a garbage collection run.
+ * - time precision isn't particularly important
+ */
+void key_schedule_gc(time64_t gc_at)
+{
+	unsigned long expires;
+	time64_t now = ktime_get_real_seconds();
+
+	kenter("%lld", gc_at - now);
+
+	if (gc_at <= now || test_bit(KEY_GC_REAP_KEYTYPE, &key_gc_flags)) {
+		kdebug("IMMEDIATE");
+		schedule_work(&key_gc_work);
+	} else if (gc_at < key_gc_next_run) {
+		kdebug("DEFERRED");
+		key_gc_next_run = gc_at;
+		expires = jiffies + (gc_at - now) * HZ;
+		mod_timer(&key_gc_timer, expires);
+	}
+}
+
+/*
+ * Schedule a dead links collection run.
+ */
+void key_schedule_gc_links(void)
+{
+	set_bit(KEY_GC_KEY_EXPIRED, &key_gc_flags);
+	schedule_work(&key_gc_work);
+}
+
+/*
+ * Some key's cleanup time was met after it expired, so we need to get the
+ * reaper to go through a cycle finding expired keys.
+ */
+static void key_gc_timer_func(struct timer_list *unused)
+{
+	kenter("");
+	key_gc_next_run = TIME64_MAX;
+	key_schedule_gc_links();
+}
+
+/*
+ * Reap keys of dead type.
+ *
+ * We use three flags to make sure we see three complete cycles of the garbage
+ * collector: the first to mark keys of that type as being dead, the second to
+ * collect dead links and the third to clean up the dead keys.  We have to be
+ * careful as there may already be a cycle in progress.
+ *
+ * The caller must be holding key_types_sem.
+ */
+void key_gc_keytype(struct key_type *ktype)
+{
+	kenter("%s", ktype->name);
+
+	key_gc_dead_keytype = ktype;
+	set_bit(KEY_GC_REAPING_KEYTYPE, &key_gc_flags);
+	smp_mb();
+	set_bit(KEY_GC_REAP_KEYTYPE, &key_gc_flags);
+
+	kdebug("schedule");
+	schedule_work(&key_gc_work);
+
+	kdebug("sleep");
+	wait_on_bit(&key_gc_flags, KEY_GC_REAPING_KEYTYPE,
+		    TASK_UNINTERRUPTIBLE);
+
+	key_gc_dead_keytype = NULL;
+	kleave("");
+}
+
+/*
+ * Garbage collect a list of unreferenced, detached keys
+ */
+static noinline void key_gc_unused_keys(struct list_head *keys)
+{
+	while (!list_empty(keys)) {
+		struct key *key =
+			list_entry(keys->next, struct key, graveyard_link);
+		short state = key->state;
+
+		list_del(&key->graveyard_link);
+
+		kdebug("- %u", key->serial);
+		key_check(key);
+
+		/* Throw away the key data if the key is instantiated */
+		if (state == KEY_IS_POSITIVE && key->type->destroy)
+			key->type->destroy(key);
+
+		security_key_free(key);
+
+		/* deal with the user's key tracking and quota */
+		if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+			spin_lock(&key->user->lock);
+			key->user->qnkeys--;
+			key->user->qnbytes -= key->quotalen;
+			spin_unlock(&key->user->lock);
+		}
+
+		atomic_dec(&key->user->nkeys);
+		if (state != KEY_IS_UNINSTANTIATED)
+			atomic_dec(&key->user->nikeys);
+
+		key_user_put(key->user);
+
+		kfree(key->description);
+
+		memzero_explicit(key, sizeof(*key));
+		kmem_cache_free(key_jar, key);
+	}
+}
+
+/*
+ * Garbage collector for unused keys.
+ *
+ * This is done in process context so that we don't have to disable interrupts
+ * all over the place.  key_put() schedules this rather than trying to do the
+ * cleanup itself, which means key_put() doesn't have to sleep.
+ */
+static void key_garbage_collector(struct work_struct *work)
+{
+	static LIST_HEAD(graveyard);
+	static u8 gc_state;		/* Internal persistent state */
+#define KEY_GC_REAP_AGAIN	0x01	/* - Need another cycle */
+#define KEY_GC_REAPING_LINKS	0x02	/* - We need to reap links */
+#define KEY_GC_SET_TIMER	0x04	/* - We need to restart the timer */
+#define KEY_GC_REAPING_DEAD_1	0x10	/* - We need to mark dead keys */
+#define KEY_GC_REAPING_DEAD_2	0x20	/* - We need to reap dead key links */
+#define KEY_GC_REAPING_DEAD_3	0x40	/* - We need to reap dead keys */
+#define KEY_GC_FOUND_DEAD_KEY	0x80	/* - We found at least one dead key */
+
+	struct rb_node *cursor;
+	struct key *key;
+	time64_t new_timer, limit;
+
+	kenter("[%lx,%x]", key_gc_flags, gc_state);
+
+	limit = ktime_get_real_seconds();
+	if (limit > key_gc_delay)
+		limit -= key_gc_delay;
+	else
+		limit = key_gc_delay;
+
+	/* Work out what we're going to be doing in this pass */
+	gc_state &= KEY_GC_REAPING_DEAD_1 | KEY_GC_REAPING_DEAD_2;
+	gc_state <<= 1;
+	if (test_and_clear_bit(KEY_GC_KEY_EXPIRED, &key_gc_flags))
+		gc_state |= KEY_GC_REAPING_LINKS | KEY_GC_SET_TIMER;
+
+	if (test_and_clear_bit(KEY_GC_REAP_KEYTYPE, &key_gc_flags))
+		gc_state |= KEY_GC_REAPING_DEAD_1;
+	kdebug("new pass %x", gc_state);
+
+	new_timer = TIME64_MAX;
+
+	/* As only this function is permitted to remove things from the key
+	 * serial tree, if cursor is non-NULL then it will always point to a
+	 * valid node in the tree - even if lock got dropped.
+	 */
+	spin_lock(&key_serial_lock);
+	cursor = rb_first(&key_serial_tree);
+
+continue_scanning:
+	while (cursor) {
+		key = rb_entry(cursor, struct key, serial_node);
+		cursor = rb_next(cursor);
+
+		if (refcount_read(&key->usage) == 0)
+			goto found_unreferenced_key;
+
+		if (unlikely(gc_state & KEY_GC_REAPING_DEAD_1)) {
+			if (key->type == key_gc_dead_keytype) {
+				gc_state |= KEY_GC_FOUND_DEAD_KEY;
+				set_bit(KEY_FLAG_DEAD, &key->flags);
+				key->perm = 0;
+				goto skip_dead_key;
+			} else if (key->type == &key_type_keyring &&
+				   key->restrict_link) {
+				goto found_restricted_keyring;
+			}
+		}
+
+		if (gc_state & KEY_GC_SET_TIMER) {
+			if (key->expiry > limit && key->expiry < new_timer) {
+				kdebug("will expire %x in %lld",
+				       key_serial(key), key->expiry - limit);
+				new_timer = key->expiry;
+			}
+		}
+
+		if (unlikely(gc_state & KEY_GC_REAPING_DEAD_2))
+			if (key->type == key_gc_dead_keytype)
+				gc_state |= KEY_GC_FOUND_DEAD_KEY;
+
+		if ((gc_state & KEY_GC_REAPING_LINKS) ||
+		    unlikely(gc_state & KEY_GC_REAPING_DEAD_2)) {
+			if (key->type == &key_type_keyring)
+				goto found_keyring;
+		}
+
+		if (unlikely(gc_state & KEY_GC_REAPING_DEAD_3))
+			if (key->type == key_gc_dead_keytype)
+				goto destroy_dead_key;
+
+	skip_dead_key:
+		if (spin_is_contended(&key_serial_lock) || need_resched())
+			goto contended;
+	}
+
+contended:
+	spin_unlock(&key_serial_lock);
+
+maybe_resched:
+	if (cursor) {
+		cond_resched();
+		spin_lock(&key_serial_lock);
+		goto continue_scanning;
+	}
+
+	/* We've completed the pass.  Set the timer if we need to and queue a
+	 * new cycle if necessary.  We keep executing cycles until we find one
+	 * where we didn't reap any keys.
+	 */
+	kdebug("pass complete");
+
+	if (gc_state & KEY_GC_SET_TIMER && new_timer != (time64_t)TIME64_MAX) {
+		new_timer += key_gc_delay;
+		key_schedule_gc(new_timer);
+	}
+
+	if (unlikely(gc_state & KEY_GC_REAPING_DEAD_2) ||
+	    !list_empty(&graveyard)) {
+		/* Make sure that all pending keyring payload destructions are
+		 * fulfilled and that people aren't now looking at dead or
+		 * dying keys that they don't have a reference upon or a link
+		 * to.
+		 */
+		kdebug("gc sync");
+		synchronize_rcu();
+	}
+
+	if (!list_empty(&graveyard)) {
+		kdebug("gc keys");
+		key_gc_unused_keys(&graveyard);
+	}
+
+	if (unlikely(gc_state & (KEY_GC_REAPING_DEAD_1 |
+				 KEY_GC_REAPING_DEAD_2))) {
+		if (!(gc_state & KEY_GC_FOUND_DEAD_KEY)) {
+			/* No remaining dead keys: short circuit the remaining
+			 * keytype reap cycles.
+			 */
+			kdebug("dead short");
+			gc_state &= ~(KEY_GC_REAPING_DEAD_1 | KEY_GC_REAPING_DEAD_2);
+			gc_state |= KEY_GC_REAPING_DEAD_3;
+		} else {
+			gc_state |= KEY_GC_REAP_AGAIN;
+		}
+	}
+
+	if (unlikely(gc_state & KEY_GC_REAPING_DEAD_3)) {
+		kdebug("dead wake");
+		smp_mb();
+		clear_bit(KEY_GC_REAPING_KEYTYPE, &key_gc_flags);
+		wake_up_bit(&key_gc_flags, KEY_GC_REAPING_KEYTYPE);
+	}
+
+	if (gc_state & KEY_GC_REAP_AGAIN)
+		schedule_work(&key_gc_work);
+	kleave(" [end %x]", gc_state);
+	return;
+
+	/* We found an unreferenced key - once we've removed it from the tree,
+	 * we can safely drop the lock.
+	 */
+found_unreferenced_key:
+	kdebug("unrefd key %d", key->serial);
+	rb_erase(&key->serial_node, &key_serial_tree);
+	spin_unlock(&key_serial_lock);
+
+	list_add_tail(&key->graveyard_link, &graveyard);
+	gc_state |= KEY_GC_REAP_AGAIN;
+	goto maybe_resched;
+
+	/* We found a restricted keyring and need to update the restriction if
+	 * it is associated with the dead key type.
+	 */
+found_restricted_keyring:
+	spin_unlock(&key_serial_lock);
+	keyring_restriction_gc(key, key_gc_dead_keytype);
+	goto maybe_resched;
+
+	/* We found a keyring and we need to check the payload for links to
+	 * dead or expired keys.  We don't flag another reap immediately as we
+	 * have to wait for the old payload to be destroyed by RCU before we
+	 * can reap the keys to which it refers.
+	 */
+found_keyring:
+	spin_unlock(&key_serial_lock);
+	keyring_gc(key, limit);
+	goto maybe_resched;
+
+	/* We found a dead key that is still referenced.  Reset its type and
+	 * destroy its payload with its semaphore held.
+	 */
+destroy_dead_key:
+	spin_unlock(&key_serial_lock);
+	kdebug("destroy key %d", key->serial);
+	down_write(&key->sem);
+	key->type = &key_type_dead;
+	if (key_gc_dead_keytype->destroy)
+		key_gc_dead_keytype->destroy(key);
+	memset(&key->payload, KEY_DESTROY, sizeof(key->payload));
+	up_write(&key->sem);
+	goto maybe_resched;
+}
diff --git a/security/keys/internal.h b/security/keys/internal.h
new file mode 100644
index 000000000..d1b9c5957
--- /dev/null
+++ b/security/keys/internal.h
@@ -0,0 +1,309 @@
+/* Authentication token and access key management internal defs
+ *
+ * Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _INTERNAL_H
+#define _INTERNAL_H
+
+#include <linux/sched.h>
+#include <linux/wait_bit.h>
+#include <linux/cred.h>
+#include <linux/key-type.h>
+#include <linux/task_work.h>
+#include <linux/keyctl.h>
+#include <linux/refcount.h>
+#include <linux/compat.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+
+struct iovec;
+
+#ifdef __KDEBUG
+#define kenter(FMT, ...) \
+	printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+	printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+#define kdebug(FMT, ...) \
+	printk(KERN_DEBUG "   "FMT"\n", ##__VA_ARGS__)
+#else
+#define kenter(FMT, ...) \
+	no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+	no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+#define kdebug(FMT, ...) \
+	no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
+#endif
+
+extern struct key_type key_type_dead;
+extern struct key_type key_type_user;
+extern struct key_type key_type_logon;
+
+/*****************************************************************************/
+/*
+ * Keep track of keys for a user.
+ *
+ * This needs to be separate to user_struct to avoid a refcount-loop
+ * (user_struct pins some keyrings which pin this struct).
+ *
+ * We also keep track of keys under request from userspace for this UID here.
+ */
+struct key_user {
+	struct rb_node		node;
+	struct mutex		cons_lock;	/* construction initiation lock */
+	spinlock_t		lock;
+	refcount_t		usage;		/* for accessing qnkeys & qnbytes */
+	atomic_t		nkeys;		/* number of keys */
+	atomic_t		nikeys;		/* number of instantiated keys */
+	kuid_t			uid;
+	int			qnkeys;		/* number of keys allocated to this user */
+	int			qnbytes;	/* number of bytes allocated to this user */
+};
+
+extern struct rb_root	key_user_tree;
+extern spinlock_t	key_user_lock;
+extern struct key_user	root_key_user;
+
+extern struct key_user *key_user_lookup(kuid_t uid);
+extern void key_user_put(struct key_user *user);
+
+/*
+ * Key quota limits.
+ * - root has its own separate limits to everyone else
+ */
+extern unsigned key_quota_root_maxkeys;
+extern unsigned key_quota_root_maxbytes;
+extern unsigned key_quota_maxkeys;
+extern unsigned key_quota_maxbytes;
+
+#define KEYQUOTA_LINK_BYTES	4		/* a link in a keyring is worth 4 bytes */
+
+
+extern struct kmem_cache *key_jar;
+extern struct rb_root key_serial_tree;
+extern spinlock_t key_serial_lock;
+extern struct mutex key_construction_mutex;
+extern wait_queue_head_t request_key_conswq;
+
+
+extern struct key_type *key_type_lookup(const char *type);
+extern void key_type_put(struct key_type *ktype);
+
+extern int __key_link_begin(struct key *keyring,
+			    const struct keyring_index_key *index_key,
+			    struct assoc_array_edit **_edit);
+extern int __key_link_check_live_key(struct key *keyring, struct key *key);
+extern void __key_link(struct key *key, struct assoc_array_edit **_edit);
+extern void __key_link_end(struct key *keyring,
+			   const struct keyring_index_key *index_key,
+			   struct assoc_array_edit *edit);
+
+extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
+				    const struct keyring_index_key *index_key);
+
+extern struct key *keyring_search_instkey(struct key *keyring,
+					  key_serial_t target_id);
+
+extern int iterate_over_keyring(const struct key *keyring,
+				int (*func)(const struct key *key, void *data),
+				void *data);
+
+struct keyring_search_context {
+	struct keyring_index_key index_key;
+	const struct cred	*cred;
+	struct key_match_data	match_data;
+	unsigned		flags;
+#define KEYRING_SEARCH_NO_STATE_CHECK	0x0001	/* Skip state checks */
+#define KEYRING_SEARCH_DO_STATE_CHECK	0x0002	/* Override NO_STATE_CHECK */
+#define KEYRING_SEARCH_NO_UPDATE_TIME	0x0004	/* Don't update times */
+#define KEYRING_SEARCH_NO_CHECK_PERM	0x0008	/* Don't check permissions */
+#define KEYRING_SEARCH_DETECT_TOO_DEEP	0x0010	/* Give an error on excessive depth */
+#define KEYRING_SEARCH_SKIP_EXPIRED	0x0020	/* Ignore expired keys (intention to replace) */
+
+	int (*iterator)(const void *object, void *iterator_data);
+
+	/* Internal stuff */
+	int			skipped_ret;
+	bool			possessed;
+	key_ref_t		result;
+	time64_t		now;
+};
+
+extern bool key_default_cmp(const struct key *key,
+			    const struct key_match_data *match_data);
+extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
+				    struct keyring_search_context *ctx);
+
+extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
+extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
+
+extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);
+
+extern int install_user_keyrings(void);
+extern int install_thread_keyring_to_cred(struct cred *);
+extern int install_process_keyring_to_cred(struct cred *);
+extern int install_session_keyring_to_cred(struct cred *, struct key *);
+
+extern struct key *request_key_and_link(struct key_type *type,
+					const char *description,
+					const void *callout_info,
+					size_t callout_len,
+					void *aux,
+					struct key *dest_keyring,
+					unsigned long flags);
+
+extern bool lookup_user_key_possessed(const struct key *key,
+				      const struct key_match_data *match_data);
+extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
+				 key_perm_t perm);
+#define KEY_LOOKUP_CREATE	0x01
+#define KEY_LOOKUP_PARTIAL	0x02
+#define KEY_LOOKUP_FOR_UNLINK	0x04
+
+extern long join_session_keyring(const char *name);
+extern void key_change_session_keyring(struct callback_head *twork);
+
+extern struct work_struct key_gc_work;
+extern unsigned key_gc_delay;
+extern void keyring_gc(struct key *keyring, time64_t limit);
+extern void keyring_restriction_gc(struct key *keyring,
+				   struct key_type *dead_type);
+extern void key_schedule_gc(time64_t gc_at);
+extern void key_schedule_gc_links(void);
+extern void key_gc_keytype(struct key_type *ktype);
+
+extern int key_task_permission(const key_ref_t key_ref,
+			       const struct cred *cred,
+			       key_perm_t perm);
+
+/*
+ * Check to see whether permission is granted to use a key in the desired way.
+ */
+static inline int key_permission(const key_ref_t key_ref, unsigned perm)
+{
+	return key_task_permission(key_ref, current_cred(), perm);
+}
+
+extern struct key_type key_type_request_key_auth;
+extern struct key *request_key_auth_new(struct key *target,
+					const char *op,
+					const void *callout_info,
+					size_t callout_len,
+					struct key *dest_keyring);
+
+extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
+
+/*
+ * Determine whether a key is dead.
+ */
+static inline bool key_is_dead(const struct key *key, time64_t limit)
+{
+	return
+		key->flags & ((1 << KEY_FLAG_DEAD) |
+			      (1 << KEY_FLAG_INVALIDATED)) ||
+		(key->expiry > 0 && key->expiry <= limit);
+}
+
+/*
+ * keyctl() functions
+ */
+extern long keyctl_get_keyring_ID(key_serial_t, int);
+extern long keyctl_join_session_keyring(const char __user *);
+extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
+extern long keyctl_revoke_key(key_serial_t);
+extern long keyctl_keyring_clear(key_serial_t);
+extern long keyctl_keyring_link(key_serial_t, key_serial_t);
+extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
+extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
+extern long keyctl_keyring_search(key_serial_t, const char __user *,
+				  const char __user *, key_serial_t);
+extern long keyctl_read_key(key_serial_t, char __user *, size_t);
+extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
+extern long keyctl_setperm_key(key_serial_t, key_perm_t);
+extern long keyctl_instantiate_key(key_serial_t, const void __user *,
+				   size_t, key_serial_t);
+extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
+extern long keyctl_set_reqkey_keyring(int);
+extern long keyctl_set_timeout(key_serial_t, unsigned);
+extern long keyctl_assume_authority(key_serial_t);
+extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
+				size_t buflen);
+extern long keyctl_session_to_parent(void);
+extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
+extern long keyctl_instantiate_key_iov(key_serial_t,
+				       const struct iovec __user *,
+				       unsigned, key_serial_t);
+extern long keyctl_invalidate_key(key_serial_t);
+
+struct iov_iter;
+extern long keyctl_instantiate_key_common(key_serial_t,
+					  struct iov_iter *,
+					  key_serial_t);
+extern long keyctl_restrict_keyring(key_serial_t id,
+				    const char __user *_type,
+				    const char __user *_restriction);
+#ifdef CONFIG_PERSISTENT_KEYRINGS
+extern long keyctl_get_persistent(uid_t, key_serial_t);
+extern unsigned persistent_keyring_expiry;
+#else
+static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
+#ifdef CONFIG_KEY_DH_OPERATIONS
+extern long keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
+			      size_t, struct keyctl_kdf_params __user *);
+extern long __keyctl_dh_compute(struct keyctl_dh_params __user *, char __user *,
+				size_t, struct keyctl_kdf_params *);
+#ifdef CONFIG_KEYS_COMPAT
+extern long compat_keyctl_dh_compute(struct keyctl_dh_params __user *params,
+				char __user *buffer, size_t buflen,
+				struct compat_keyctl_kdf_params __user *kdf);
+#endif
+#define KEYCTL_KDF_MAX_OUTPUT_LEN	1024	/* max length of KDF output */
+#define KEYCTL_KDF_MAX_OI_LEN		64	/* max length of otherinfo */
+#else
+static inline long keyctl_dh_compute(struct keyctl_dh_params __user *params,
+				     char __user *buffer, size_t buflen,
+				     struct keyctl_kdf_params __user *kdf)
+{
+	return -EOPNOTSUPP;
+}
+
+#ifdef CONFIG_KEYS_COMPAT
+static inline long compat_keyctl_dh_compute(
+				struct keyctl_dh_params __user *params,
+				char __user *buffer, size_t buflen,
+				struct keyctl_kdf_params __user *kdf)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+#endif
+
+/*
+ * Debugging key validation
+ */
+#ifdef KEY_DEBUGGING
+extern void __key_check(const struct key *);
+
+static inline void key_check(const struct key *key)
+{
+	if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
+		__key_check(key);
+}
+
+#else
+
+#define key_check(key) do {} while(0)
+
+#endif
+#endif /* _INTERNAL_H */
diff --git a/security/keys/key.c b/security/keys/key.c
new file mode 100644
index 000000000..d3ebc0533
--- /dev/null
+++ b/security/keys/key.c
@@ -0,0 +1,1184 @@
+/* Basic authentication token and access key management
+ *
+ * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/poison.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/workqueue.h>
+#include <linux/random.h>
+#include <linux/err.h>
+#include "internal.h"
+
+struct kmem_cache *key_jar;
+struct rb_root		key_serial_tree; /* tree of keys indexed by serial */
+DEFINE_SPINLOCK(key_serial_lock);
+
+struct rb_root	key_user_tree; /* tree of quota records indexed by UID */
+DEFINE_SPINLOCK(key_user_lock);
+
+unsigned int key_quota_root_maxkeys = 1000000;	/* root's key count quota */
+unsigned int key_quota_root_maxbytes = 25000000; /* root's key space quota */
+unsigned int key_quota_maxkeys = 200;		/* general key count quota */
+unsigned int key_quota_maxbytes = 20000;	/* general key space quota */
+
+static LIST_HEAD(key_types_list);
+static DECLARE_RWSEM(key_types_sem);
+
+/* We serialise key instantiation and link */
+DEFINE_MUTEX(key_construction_mutex);
+
+#ifdef KEY_DEBUGGING
+void __key_check(const struct key *key)
+{
+	printk("__key_check: key %p {%08x} should be {%08x}\n",
+	       key, key->magic, KEY_DEBUG_MAGIC);
+	BUG();
+}
+#endif
+
+/*
+ * Get the key quota record for a user, allocating a new record if one doesn't
+ * already exist.
+ */
+struct key_user *key_user_lookup(kuid_t uid)
+{
+	struct key_user *candidate = NULL, *user;
+	struct rb_node *parent, **p;
+
+try_again:
+	parent = NULL;
+	p = &key_user_tree.rb_node;
+	spin_lock(&key_user_lock);
+
+	/* search the tree for a user record with a matching UID */
+	while (*p) {
+		parent = *p;
+		user = rb_entry(parent, struct key_user, node);
+
+		if (uid_lt(uid, user->uid))
+			p = &(*p)->rb_left;
+		else if (uid_gt(uid, user->uid))
+			p = &(*p)->rb_right;
+		else
+			goto found;
+	}
+
+	/* if we get here, we failed to find a match in the tree */
+	if (!candidate) {
+		/* allocate a candidate user record if we don't already have
+		 * one */
+		spin_unlock(&key_user_lock);
+
+		user = NULL;
+		candidate = kmalloc(sizeof(struct key_user), GFP_KERNEL);
+		if (unlikely(!candidate))
+			goto out;
+
+		/* the allocation may have scheduled, so we need to repeat the
+		 * search lest someone else added the record whilst we were
+		 * asleep */
+		goto try_again;
+	}
+
+	/* if we get here, then the user record still hadn't appeared on the
+	 * second pass - so we use the candidate record */
+	refcount_set(&candidate->usage, 1);
+	atomic_set(&candidate->nkeys, 0);
+	atomic_set(&candidate->nikeys, 0);
+	candidate->uid = uid;
+	candidate->qnkeys = 0;
+	candidate->qnbytes = 0;
+	spin_lock_init(&candidate->lock);
+	mutex_init(&candidate->cons_lock);
+
+	rb_link_node(&candidate->node, parent, p);
+	rb_insert_color(&candidate->node, &key_user_tree);
+	spin_unlock(&key_user_lock);
+	user = candidate;
+	goto out;
+
+	/* okay - we found a user record for this UID */
+found:
+	refcount_inc(&user->usage);
+	spin_unlock(&key_user_lock);
+	kfree(candidate);
+out:
+	return user;
+}
+
+/*
+ * Dispose of a user structure
+ */
+void key_user_put(struct key_user *user)
+{
+	if (refcount_dec_and_lock(&user->usage, &key_user_lock)) {
+		rb_erase(&user->node, &key_user_tree);
+		spin_unlock(&key_user_lock);
+
+		kfree(user);
+	}
+}
+
+/*
+ * Allocate a serial number for a key.  These are assigned randomly to avoid
+ * security issues through covert channel problems.
+ */
+static inline void key_alloc_serial(struct key *key)
+{
+	struct rb_node *parent, **p;
+	struct key *xkey;
+
+	/* propose a random serial number and look for a hole for it in the
+	 * serial number tree */
+	do {
+		get_random_bytes(&key->serial, sizeof(key->serial));
+
+		key->serial >>= 1; /* negative numbers are not permitted */
+	} while (key->serial < 3);
+
+	spin_lock(&key_serial_lock);
+
+attempt_insertion:
+	parent = NULL;
+	p = &key_serial_tree.rb_node;
+
+	while (*p) {
+		parent = *p;
+		xkey = rb_entry(parent, struct key, serial_node);
+
+		if (key->serial < xkey->serial)
+			p = &(*p)->rb_left;
+		else if (key->serial > xkey->serial)
+			p = &(*p)->rb_right;
+		else
+			goto serial_exists;
+	}
+
+	/* we've found a suitable hole - arrange for this key to occupy it */
+	rb_link_node(&key->serial_node, parent, p);
+	rb_insert_color(&key->serial_node, &key_serial_tree);
+
+	spin_unlock(&key_serial_lock);
+	return;
+
+	/* we found a key with the proposed serial number - walk the tree from
+	 * that point looking for the next unused serial number */
+serial_exists:
+	for (;;) {
+		key->serial++;
+		if (key->serial < 3) {
+			key->serial = 3;
+			goto attempt_insertion;
+		}
+
+		parent = rb_next(parent);
+		if (!parent)
+			goto attempt_insertion;
+
+		xkey = rb_entry(parent, struct key, serial_node);
+		if (key->serial < xkey->serial)
+			goto attempt_insertion;
+	}
+}
+
+/**
+ * key_alloc - Allocate a key of the specified type.
+ * @type: The type of key to allocate.
+ * @desc: The key description to allow the key to be searched out.
+ * @uid: The owner of the new key.
+ * @gid: The group ID for the new key's group permissions.
+ * @cred: The credentials specifying UID namespace.
+ * @perm: The permissions mask of the new key.
+ * @flags: Flags specifying quota properties.
+ * @restrict_link: Optional link restriction for new keyrings.
+ *
+ * Allocate a key of the specified type with the attributes given.  The key is
+ * returned in an uninstantiated state and the caller needs to instantiate the
+ * key before returning.
+ *
+ * The restrict_link structure (if not NULL) will be freed when the
+ * keyring is destroyed, so it must be dynamically allocated.
+ *
+ * The user's key count quota is updated to reflect the creation of the key and
+ * the user's key data quota has the default for the key type reserved.  The
+ * instantiation function should amend this as necessary.  If insufficient
+ * quota is available, -EDQUOT will be returned.
+ *
+ * The LSM security modules can prevent a key being created, in which case
+ * -EACCES will be returned.
+ *
+ * Returns a pointer to the new key if successful and an error code otherwise.
+ *
+ * Note that the caller needs to ensure the key type isn't uninstantiated.
+ * Internally this can be done by locking key_types_sem.  Externally, this can
+ * be done by either never unregistering the key type, or making sure
+ * key_alloc() calls don't race with module unloading.
+ */
+struct key *key_alloc(struct key_type *type, const char *desc,
+		      kuid_t uid, kgid_t gid, const struct cred *cred,
+		      key_perm_t perm, unsigned long flags,
+		      struct key_restriction *restrict_link)
+{
+	struct key_user *user = NULL;
+	struct key *key;
+	size_t desclen, quotalen;
+	int ret;
+
+	key = ERR_PTR(-EINVAL);
+	if (!desc || !*desc)
+		goto error;
+
+	if (type->vet_description) {
+		ret = type->vet_description(desc);
+		if (ret < 0) {
+			key = ERR_PTR(ret);
+			goto error;
+		}
+	}
+
+	desclen = strlen(desc);
+	quotalen = desclen + 1 + type->def_datalen;
+
+	/* get hold of the key tracking for this user */
+	user = key_user_lookup(uid);
+	if (!user)
+		goto no_memory_1;
+
+	/* check that the user's quota permits allocation of another key and
+	 * its description */
+	if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+		unsigned maxkeys = uid_eq(uid, GLOBAL_ROOT_UID) ?
+			key_quota_root_maxkeys : key_quota_maxkeys;
+		unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ?
+			key_quota_root_maxbytes : key_quota_maxbytes;
+
+		spin_lock(&user->lock);
+		if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
+			if (user->qnkeys + 1 > maxkeys ||
+			    user->qnbytes + quotalen > maxbytes ||
+			    user->qnbytes + quotalen < user->qnbytes)
+				goto no_quota;
+		}
+
+		user->qnkeys++;
+		user->qnbytes += quotalen;
+		spin_unlock(&user->lock);
+	}
+
+	/* allocate and initialise the key and its description */
+	key = kmem_cache_zalloc(key_jar, GFP_KERNEL);
+	if (!key)
+		goto no_memory_2;
+
+	key->index_key.desc_len = desclen;
+	key->index_key.description = kmemdup(desc, desclen + 1, GFP_KERNEL);
+	if (!key->index_key.description)
+		goto no_memory_3;
+
+	refcount_set(&key->usage, 1);
+	init_rwsem(&key->sem);
+	lockdep_set_class(&key->sem, &type->lock_class);
+	key->index_key.type = type;
+	key->user = user;
+	key->quotalen = quotalen;
+	key->datalen = type->def_datalen;
+	key->uid = uid;
+	key->gid = gid;
+	key->perm = perm;
+	key->restrict_link = restrict_link;
+	key->last_used_at = ktime_get_real_seconds();
+
+	if (!(flags & KEY_ALLOC_NOT_IN_QUOTA))
+		key->flags |= 1 << KEY_FLAG_IN_QUOTA;
+	if (flags & KEY_ALLOC_BUILT_IN)
+		key->flags |= 1 << KEY_FLAG_BUILTIN;
+	if (flags & KEY_ALLOC_UID_KEYRING)
+		key->flags |= 1 << KEY_FLAG_UID_KEYRING;
+	if (flags & KEY_ALLOC_SET_KEEP)
+		key->flags |= 1 << KEY_FLAG_KEEP;
+
+#ifdef KEY_DEBUGGING
+	key->magic = KEY_DEBUG_MAGIC;
+#endif
+
+	/* let the security module know about the key */
+	ret = security_key_alloc(key, cred, flags);
+	if (ret < 0)
+		goto security_error;
+
+	/* publish the key by giving it a serial number */
+	atomic_inc(&user->nkeys);
+	key_alloc_serial(key);
+
+error:
+	return key;
+
+security_error:
+	kfree(key->description);
+	kmem_cache_free(key_jar, key);
+	if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+		spin_lock(&user->lock);
+		user->qnkeys--;
+		user->qnbytes -= quotalen;
+		spin_unlock(&user->lock);
+	}
+	key_user_put(user);
+	key = ERR_PTR(ret);
+	goto error;
+
+no_memory_3:
+	kmem_cache_free(key_jar, key);
+no_memory_2:
+	if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+		spin_lock(&user->lock);
+		user->qnkeys--;
+		user->qnbytes -= quotalen;
+		spin_unlock(&user->lock);
+	}
+	key_user_put(user);
+no_memory_1:
+	key = ERR_PTR(-ENOMEM);
+	goto error;
+
+no_quota:
+	spin_unlock(&user->lock);
+	key_user_put(user);
+	key = ERR_PTR(-EDQUOT);
+	goto error;
+}
+EXPORT_SYMBOL(key_alloc);
+
+/**
+ * key_payload_reserve - Adjust data quota reservation for the key's payload
+ * @key: The key to make the reservation for.
+ * @datalen: The amount of data payload the caller now wants.
+ *
+ * Adjust the amount of the owning user's key data quota that a key reserves.
+ * If the amount is increased, then -EDQUOT may be returned if there isn't
+ * enough free quota available.
+ *
+ * If successful, 0 is returned.
+ */
+int key_payload_reserve(struct key *key, size_t datalen)
+{
+	int delta = (int)datalen - key->datalen;
+	int ret = 0;
+
+	key_check(key);
+
+	/* contemplate the quota adjustment */
+	if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+		unsigned maxbytes = uid_eq(key->user->uid, GLOBAL_ROOT_UID) ?
+			key_quota_root_maxbytes : key_quota_maxbytes;
+
+		spin_lock(&key->user->lock);
+
+		if (delta > 0 &&
+		    (key->user->qnbytes + delta > maxbytes ||
+		     key->user->qnbytes + delta < key->user->qnbytes)) {
+			ret = -EDQUOT;
+		}
+		else {
+			key->user->qnbytes += delta;
+			key->quotalen += delta;
+		}
+		spin_unlock(&key->user->lock);
+	}
+
+	/* change the recorded data length if that didn't generate an error */
+	if (ret == 0)
+		key->datalen = datalen;
+
+	return ret;
+}
+EXPORT_SYMBOL(key_payload_reserve);
+
+/*
+ * Change the key state to being instantiated.
+ */
+static void mark_key_instantiated(struct key *key, int reject_error)
+{
+	/* Commit the payload before setting the state; barrier versus
+	 * key_read_state().
+	 */
+	smp_store_release(&key->state,
+			  (reject_error < 0) ? reject_error : KEY_IS_POSITIVE);
+}
+
+/*
+ * Instantiate a key and link it into the target keyring atomically.  Must be
+ * called with the target keyring's semaphore writelocked.  The target key's
+ * semaphore need not be locked as instantiation is serialised by
+ * key_construction_mutex.
+ */
+static int __key_instantiate_and_link(struct key *key,
+				      struct key_preparsed_payload *prep,
+				      struct key *keyring,
+				      struct key *authkey,
+				      struct assoc_array_edit **_edit)
+{
+	int ret, awaken;
+
+	key_check(key);
+	key_check(keyring);
+
+	awaken = 0;
+	ret = -EBUSY;
+
+	mutex_lock(&key_construction_mutex);
+
+	/* can't instantiate twice */
+	if (key->state == KEY_IS_UNINSTANTIATED) {
+		/* instantiate the key */
+		ret = key->type->instantiate(key, prep);
+
+		if (ret == 0) {
+			/* mark the key as being instantiated */
+			atomic_inc(&key->user->nikeys);
+			mark_key_instantiated(key, 0);
+
+			if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
+				awaken = 1;
+
+			/* and link it into the destination keyring */
+			if (keyring) {
+				if (test_bit(KEY_FLAG_KEEP, &keyring->flags))
+					set_bit(KEY_FLAG_KEEP, &key->flags);
+
+				__key_link(key, _edit);
+			}
+
+			/* disable the authorisation key */
+			if (authkey)
+				key_revoke(authkey);
+
+			if (prep->expiry != TIME64_MAX) {
+				key->expiry = prep->expiry;
+				key_schedule_gc(prep->expiry + key_gc_delay);
+			}
+		}
+	}
+
+	mutex_unlock(&key_construction_mutex);
+
+	/* wake up anyone waiting for a key to be constructed */
+	if (awaken)
+		wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT);
+
+	return ret;
+}
+
+/**
+ * key_instantiate_and_link - Instantiate a key and link it into the keyring.
+ * @key: The key to instantiate.
+ * @data: The data to use to instantiate the keyring.
+ * @datalen: The length of @data.
+ * @keyring: Keyring to create a link in on success (or NULL).
+ * @authkey: The authorisation token permitting instantiation.
+ *
+ * Instantiate a key that's in the uninstantiated state using the provided data
+ * and, if successful, link it in to the destination keyring if one is
+ * supplied.
+ *
+ * If successful, 0 is returned, the authorisation token is revoked and anyone
+ * waiting for the key is woken up.  If the key was already instantiated,
+ * -EBUSY will be returned.
+ */
+int key_instantiate_and_link(struct key *key,
+			     const void *data,
+			     size_t datalen,
+			     struct key *keyring,
+			     struct key *authkey)
+{
+	struct key_preparsed_payload prep;
+	struct assoc_array_edit *edit;
+	int ret;
+
+	memset(&prep, 0, sizeof(prep));
+	prep.data = data;
+	prep.datalen = datalen;
+	prep.quotalen = key->type->def_datalen;
+	prep.expiry = TIME64_MAX;
+	if (key->type->preparse) {
+		ret = key->type->preparse(&prep);
+		if (ret < 0)
+			goto error;
+	}
+
+	if (keyring) {
+		ret = __key_link_begin(keyring, &key->index_key, &edit);
+		if (ret < 0)
+			goto error;
+
+		if (keyring->restrict_link && keyring->restrict_link->check) {
+			struct key_restriction *keyres = keyring->restrict_link;
+
+			ret = keyres->check(keyring, key->type, &prep.payload,
+					    keyres->key);
+			if (ret < 0)
+				goto error_link_end;
+		}
+	}
+
+	ret = __key_instantiate_and_link(key, &prep, keyring, authkey, &edit);
+
+error_link_end:
+	if (keyring)
+		__key_link_end(keyring, &key->index_key, edit);
+
+error:
+	if (key->type->preparse)
+		key->type->free_preparse(&prep);
+	return ret;
+}
+
+EXPORT_SYMBOL(key_instantiate_and_link);
+
+/**
+ * key_reject_and_link - Negatively instantiate a key and link it into the keyring.
+ * @key: The key to instantiate.
+ * @timeout: The timeout on the negative key.
+ * @error: The error to return when the key is hit.
+ * @keyring: Keyring to create a link in on success (or NULL).
+ * @authkey: The authorisation token permitting instantiation.
+ *
+ * Negatively instantiate a key that's in the uninstantiated state and, if
+ * successful, set its timeout and stored error and link it in to the
+ * destination keyring if one is supplied.  The key and any links to the key
+ * will be automatically garbage collected after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return the stored error code (typically ENOKEY) until the negative
+ * key expires.
+ *
+ * If successful, 0 is returned, the authorisation token is revoked and anyone
+ * waiting for the key is woken up.  If the key was already instantiated,
+ * -EBUSY will be returned.
+ */
+int key_reject_and_link(struct key *key,
+			unsigned timeout,
+			unsigned error,
+			struct key *keyring,
+			struct key *authkey)
+{
+	struct assoc_array_edit *edit;
+	int ret, awaken, link_ret = 0;
+
+	key_check(key);
+	key_check(keyring);
+
+	awaken = 0;
+	ret = -EBUSY;
+
+	if (keyring) {
+		if (keyring->restrict_link)
+			return -EPERM;
+
+		link_ret = __key_link_begin(keyring, &key->index_key, &edit);
+	}
+
+	mutex_lock(&key_construction_mutex);
+
+	/* can't instantiate twice */
+	if (key->state == KEY_IS_UNINSTANTIATED) {
+		/* mark the key as being negatively instantiated */
+		atomic_inc(&key->user->nikeys);
+		mark_key_instantiated(key, -error);
+		key->expiry = ktime_get_real_seconds() + timeout;
+		key_schedule_gc(key->expiry + key_gc_delay);
+
+		if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
+			awaken = 1;
+
+		ret = 0;
+
+		/* and link it into the destination keyring */
+		if (keyring && link_ret == 0)
+			__key_link(key, &edit);
+
+		/* disable the authorisation key */
+		if (authkey)
+			key_revoke(authkey);
+	}
+
+	mutex_unlock(&key_construction_mutex);
+
+	if (keyring && link_ret == 0)
+		__key_link_end(keyring, &key->index_key, edit);
+
+	/* wake up anyone waiting for a key to be constructed */
+	if (awaken)
+		wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT);
+
+	return ret == 0 ? link_ret : ret;
+}
+EXPORT_SYMBOL(key_reject_and_link);
+
+/**
+ * key_put - Discard a reference to a key.
+ * @key: The key to discard a reference from.
+ *
+ * Discard a reference to a key, and when all the references are gone, we
+ * schedule the cleanup task to come and pull it out of the tree in process
+ * context at some later time.
+ */
+void key_put(struct key *key)
+{
+	if (key) {
+		key_check(key);
+
+		if (refcount_dec_and_test(&key->usage))
+			schedule_work(&key_gc_work);
+	}
+}
+EXPORT_SYMBOL(key_put);
+
+/*
+ * Find a key by its serial number.
+ */
+struct key *key_lookup(key_serial_t id)
+{
+	struct rb_node *n;
+	struct key *key;
+
+	spin_lock(&key_serial_lock);
+
+	/* search the tree for the specified key */
+	n = key_serial_tree.rb_node;
+	while (n) {
+		key = rb_entry(n, struct key, serial_node);
+
+		if (id < key->serial)
+			n = n->rb_left;
+		else if (id > key->serial)
+			n = n->rb_right;
+		else
+			goto found;
+	}
+
+not_found:
+	key = ERR_PTR(-ENOKEY);
+	goto error;
+
+found:
+	/* A key is allowed to be looked up only if someone still owns a
+	 * reference to it - otherwise it's awaiting the gc.
+	 */
+	if (!refcount_inc_not_zero(&key->usage))
+		goto not_found;
+
+error:
+	spin_unlock(&key_serial_lock);
+	return key;
+}
+
+/*
+ * Find and lock the specified key type against removal.
+ *
+ * We return with the sem read-locked if successful.  If the type wasn't
+ * available -ENOKEY is returned instead.
+ */
+struct key_type *key_type_lookup(const char *type)
+{
+	struct key_type *ktype;
+
+	down_read(&key_types_sem);
+
+	/* look up the key type to see if it's one of the registered kernel
+	 * types */
+	list_for_each_entry(ktype, &key_types_list, link) {
+		if (strcmp(ktype->name, type) == 0)
+			goto found_kernel_type;
+	}
+
+	up_read(&key_types_sem);
+	ktype = ERR_PTR(-ENOKEY);
+
+found_kernel_type:
+	return ktype;
+}
+
+void key_set_timeout(struct key *key, unsigned timeout)
+{
+	time64_t expiry = 0;
+
+	/* make the changes with the locks held to prevent races */
+	down_write(&key->sem);
+
+	if (timeout > 0)
+		expiry = ktime_get_real_seconds() + timeout;
+
+	key->expiry = expiry;
+	key_schedule_gc(key->expiry + key_gc_delay);
+
+	up_write(&key->sem);
+}
+EXPORT_SYMBOL_GPL(key_set_timeout);
+
+/*
+ * Unlock a key type locked by key_type_lookup().
+ */
+void key_type_put(struct key_type *ktype)
+{
+	up_read(&key_types_sem);
+}
+
+/*
+ * Attempt to update an existing key.
+ *
+ * The key is given to us with an incremented refcount that we need to discard
+ * if we get an error.
+ */
+static inline key_ref_t __key_update(key_ref_t key_ref,
+				     struct key_preparsed_payload *prep)
+{
+	struct key *key = key_ref_to_ptr(key_ref);
+	int ret;
+
+	/* need write permission on the key to update it */
+	ret = key_permission(key_ref, KEY_NEED_WRITE);
+	if (ret < 0)
+		goto error;
+
+	ret = -EEXIST;
+	if (!key->type->update)
+		goto error;
+
+	down_write(&key->sem);
+
+	ret = key->type->update(key, prep);
+	if (ret == 0)
+		/* Updating a negative key positively instantiates it */
+		mark_key_instantiated(key, 0);
+
+	up_write(&key->sem);
+
+	if (ret < 0)
+		goto error;
+out:
+	return key_ref;
+
+error:
+	key_put(key);
+	key_ref = ERR_PTR(ret);
+	goto out;
+}
+
+/**
+ * key_create_or_update - Update or create and instantiate a key.
+ * @keyring_ref: A pointer to the destination keyring with possession flag.
+ * @type: The type of key.
+ * @description: The searchable description for the key.
+ * @payload: The data to use to instantiate or update the key.
+ * @plen: The length of @payload.
+ * @perm: The permissions mask for a new key.
+ * @flags: The quota flags for a new key.
+ *
+ * Search the destination keyring for a key of the same description and if one
+ * is found, update it, otherwise create and instantiate a new one and create a
+ * link to it from that keyring.
+ *
+ * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be
+ * concocted.
+ *
+ * Returns a pointer to the new key if successful, -ENODEV if the key type
+ * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the
+ * caller isn't permitted to modify the keyring or the LSM did not permit
+ * creation of the key.
+ *
+ * On success, the possession flag from the keyring ref will be tacked on to
+ * the key ref before it is returned.
+ */
+key_ref_t key_create_or_update(key_ref_t keyring_ref,
+			       const char *type,
+			       const char *description,
+			       const void *payload,
+			       size_t plen,
+			       key_perm_t perm,
+			       unsigned long flags)
+{
+	struct keyring_index_key index_key = {
+		.description	= description,
+	};
+	struct key_preparsed_payload prep;
+	struct assoc_array_edit *edit;
+	const struct cred *cred = current_cred();
+	struct key *keyring, *key = NULL;
+	key_ref_t key_ref;
+	int ret;
+	struct key_restriction *restrict_link = NULL;
+
+	/* look up the key type to see if it's one of the registered kernel
+	 * types */
+	index_key.type = key_type_lookup(type);
+	if (IS_ERR(index_key.type)) {
+		key_ref = ERR_PTR(-ENODEV);
+		goto error;
+	}
+
+	key_ref = ERR_PTR(-EINVAL);
+	if (!index_key.type->instantiate ||
+	    (!index_key.description && !index_key.type->preparse))
+		goto error_put_type;
+
+	keyring = key_ref_to_ptr(keyring_ref);
+
+	key_check(keyring);
+
+	if (!(flags & KEY_ALLOC_BYPASS_RESTRICTION))
+		restrict_link = keyring->restrict_link;
+
+	key_ref = ERR_PTR(-ENOTDIR);
+	if (keyring->type != &key_type_keyring)
+		goto error_put_type;
+
+	memset(&prep, 0, sizeof(prep));
+	prep.data = payload;
+	prep.datalen = plen;
+	prep.quotalen = index_key.type->def_datalen;
+	prep.expiry = TIME64_MAX;
+	if (index_key.type->preparse) {
+		ret = index_key.type->preparse(&prep);
+		if (ret < 0) {
+			key_ref = ERR_PTR(ret);
+			goto error_free_prep;
+		}
+		if (!index_key.description)
+			index_key.description = prep.description;
+		key_ref = ERR_PTR(-EINVAL);
+		if (!index_key.description)
+			goto error_free_prep;
+	}
+	index_key.desc_len = strlen(index_key.description);
+
+	ret = __key_link_begin(keyring, &index_key, &edit);
+	if (ret < 0) {
+		key_ref = ERR_PTR(ret);
+		goto error_free_prep;
+	}
+
+	if (restrict_link && restrict_link->check) {
+		ret = restrict_link->check(keyring, index_key.type,
+					   &prep.payload, restrict_link->key);
+		if (ret < 0) {
+			key_ref = ERR_PTR(ret);
+			goto error_link_end;
+		}
+	}
+
+	/* if we're going to allocate a new key, we're going to have
+	 * to modify the keyring */
+	ret = key_permission(keyring_ref, KEY_NEED_WRITE);
+	if (ret < 0) {
+		key_ref = ERR_PTR(ret);
+		goto error_link_end;
+	}
+
+	/* if it's possible to update this type of key, search for an existing
+	 * key of the same type and description in the destination keyring and
+	 * update that instead if possible
+	 */
+	if (index_key.type->update) {
+		key_ref = find_key_to_update(keyring_ref, &index_key);
+		if (key_ref)
+			goto found_matching_key;
+	}
+
+	/* if the client doesn't provide, decide on the permissions we want */
+	if (perm == KEY_PERM_UNDEF) {
+		perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR;
+		perm |= KEY_USR_VIEW;
+
+		if (index_key.type->read)
+			perm |= KEY_POS_READ;
+
+		if (index_key.type == &key_type_keyring ||
+		    index_key.type->update)
+			perm |= KEY_POS_WRITE;
+	}
+
+	/* allocate a new key */
+	key = key_alloc(index_key.type, index_key.description,
+			cred->fsuid, cred->fsgid, cred, perm, flags, NULL);
+	if (IS_ERR(key)) {
+		key_ref = ERR_CAST(key);
+		goto error_link_end;
+	}
+
+	/* instantiate it and link it into the target keyring */
+	ret = __key_instantiate_and_link(key, &prep, keyring, NULL, &edit);
+	if (ret < 0) {
+		key_put(key);
+		key_ref = ERR_PTR(ret);
+		goto error_link_end;
+	}
+
+	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
+
+error_link_end:
+	__key_link_end(keyring, &index_key, edit);
+error_free_prep:
+	if (index_key.type->preparse)
+		index_key.type->free_preparse(&prep);
+error_put_type:
+	key_type_put(index_key.type);
+error:
+	return key_ref;
+
+ found_matching_key:
+	/* we found a matching key, so we're going to try to update it
+	 * - we can drop the locks first as we have the key pinned
+	 */
+	__key_link_end(keyring, &index_key, edit);
+
+	key = key_ref_to_ptr(key_ref);
+	if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags)) {
+		ret = wait_for_key_construction(key, true);
+		if (ret < 0) {
+			key_ref_put(key_ref);
+			key_ref = ERR_PTR(ret);
+			goto error_free_prep;
+		}
+	}
+
+	key_ref = __key_update(key_ref, &prep);
+	goto error_free_prep;
+}
+EXPORT_SYMBOL(key_create_or_update);
+
+/**
+ * key_update - Update a key's contents.
+ * @key_ref: The pointer (plus possession flag) to the key.
+ * @payload: The data to be used to update the key.
+ * @plen: The length of @payload.
+ *
+ * Attempt to update the contents of a key with the given payload data.  The
+ * caller must be granted Write permission on the key.  Negative keys can be
+ * instantiated by this method.
+ *
+ * Returns 0 on success, -EACCES if not permitted and -EOPNOTSUPP if the key
+ * type does not support updating.  The key type may return other errors.
+ */
+int key_update(key_ref_t key_ref, const void *payload, size_t plen)
+{
+	struct key_preparsed_payload prep;
+	struct key *key = key_ref_to_ptr(key_ref);
+	int ret;
+
+	key_check(key);
+
+	/* the key must be writable */
+	ret = key_permission(key_ref, KEY_NEED_WRITE);
+	if (ret < 0)
+		return ret;
+
+	/* attempt to update it if supported */
+	if (!key->type->update)
+		return -EOPNOTSUPP;
+
+	memset(&prep, 0, sizeof(prep));
+	prep.data = payload;
+	prep.datalen = plen;
+	prep.quotalen = key->type->def_datalen;
+	prep.expiry = TIME64_MAX;
+	if (key->type->preparse) {
+		ret = key->type->preparse(&prep);
+		if (ret < 0)
+			goto error;
+	}
+
+	down_write(&key->sem);
+
+	ret = key->type->update(key, &prep);
+	if (ret == 0)
+		/* Updating a negative key positively instantiates it */
+		mark_key_instantiated(key, 0);
+
+	up_write(&key->sem);
+
+error:
+	if (key->type->preparse)
+		key->type->free_preparse(&prep);
+	return ret;
+}
+EXPORT_SYMBOL(key_update);
+
+/**
+ * key_revoke - Revoke a key.
+ * @key: The key to be revoked.
+ *
+ * Mark a key as being revoked and ask the type to free up its resources.  The
+ * revocation timeout is set and the key and all its links will be
+ * automatically garbage collected after key_gc_delay amount of time if they
+ * are not manually dealt with first.
+ */
+void key_revoke(struct key *key)
+{
+	time64_t time;
+
+	key_check(key);
+
+	/* make sure no one's trying to change or use the key when we mark it
+	 * - we tell lockdep that we might nest because we might be revoking an
+	 *   authorisation key whilst holding the sem on a key we've just
+	 *   instantiated
+	 */
+	down_write_nested(&key->sem, 1);
+	if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) &&
+	    key->type->revoke)
+		key->type->revoke(key);
+
+	/* set the death time to no more than the expiry time */
+	time = ktime_get_real_seconds();
+	if (key->revoked_at == 0 || key->revoked_at > time) {
+		key->revoked_at = time;
+		key_schedule_gc(key->revoked_at + key_gc_delay);
+	}
+
+	up_write(&key->sem);
+}
+EXPORT_SYMBOL(key_revoke);
+
+/**
+ * key_invalidate - Invalidate a key.
+ * @key: The key to be invalidated.
+ *
+ * Mark a key as being invalidated and have it cleaned up immediately.  The key
+ * is ignored by all searches and other operations from this point.
+ */
+void key_invalidate(struct key *key)
+{
+	kenter("%d", key_serial(key));
+
+	key_check(key);
+
+	if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
+		down_write_nested(&key->sem, 1);
+		if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags))
+			key_schedule_gc_links();
+		up_write(&key->sem);
+	}
+}
+EXPORT_SYMBOL(key_invalidate);
+
+/**
+ * generic_key_instantiate - Simple instantiation of a key from preparsed data
+ * @key: The key to be instantiated
+ * @prep: The preparsed data to load.
+ *
+ * Instantiate a key from preparsed data.  We assume we can just copy the data
+ * in directly and clear the old pointers.
+ *
+ * This can be pointed to directly by the key type instantiate op pointer.
+ */
+int generic_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
+{
+	int ret;
+
+	pr_devel("==>%s()\n", __func__);
+
+	ret = key_payload_reserve(key, prep->quotalen);
+	if (ret == 0) {
+		rcu_assign_keypointer(key, prep->payload.data[0]);
+		key->payload.data[1] = prep->payload.data[1];
+		key->payload.data[2] = prep->payload.data[2];
+		key->payload.data[3] = prep->payload.data[3];
+		prep->payload.data[0] = NULL;
+		prep->payload.data[1] = NULL;
+		prep->payload.data[2] = NULL;
+		prep->payload.data[3] = NULL;
+	}
+	pr_devel("<==%s() = %d\n", __func__, ret);
+	return ret;
+}
+EXPORT_SYMBOL(generic_key_instantiate);
+
+/**
+ * register_key_type - Register a type of key.
+ * @ktype: The new key type.
+ *
+ * Register a new key type.
+ *
+ * Returns 0 on success or -EEXIST if a type of this name already exists.
+ */
+int register_key_type(struct key_type *ktype)
+{
+	struct key_type *p;
+	int ret;
+
+	memset(&ktype->lock_class, 0, sizeof(ktype->lock_class));
+
+	ret = -EEXIST;
+	down_write(&key_types_sem);
+
+	/* disallow key types with the same name */
+	list_for_each_entry(p, &key_types_list, link) {
+		if (strcmp(p->name, ktype->name) == 0)
+			goto out;
+	}
+
+	/* store the type */
+	list_add(&ktype->link, &key_types_list);
+
+	pr_notice("Key type %s registered\n", ktype->name);
+	ret = 0;
+
+out:
+	up_write(&key_types_sem);
+	return ret;
+}
+EXPORT_SYMBOL(register_key_type);
+
+/**
+ * unregister_key_type - Unregister a type of key.
+ * @ktype: The key type.
+ *
+ * Unregister a key type and mark all the extant keys of this type as dead.
+ * Those keys of this type are then destroyed to get rid of their payloads and
+ * they and their links will be garbage collected as soon as possible.
+ */
+void unregister_key_type(struct key_type *ktype)
+{
+	down_write(&key_types_sem);
+	list_del_init(&ktype->link);
+	downgrade_write(&key_types_sem);
+	key_gc_keytype(ktype);
+	pr_notice("Key type %s unregistered\n", ktype->name);
+	up_read(&key_types_sem);
+}
+EXPORT_SYMBOL(unregister_key_type);
+
+/*
+ * Initialise the key management state.
+ */
+void __init key_init(void)
+{
+	/* allocate a slab in which we can store keys */
+	key_jar = kmem_cache_create("key_jar", sizeof(struct key),
+			0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+
+	/* add the special key types */
+	list_add_tail(&key_type_keyring.link, &key_types_list);
+	list_add_tail(&key_type_dead.link, &key_types_list);
+	list_add_tail(&key_type_user.link, &key_types_list);
+	list_add_tail(&key_type_logon.link, &key_types_list);
+
+	/* record the root user tracking */
+	rb_link_node(&root_key_user.node,
+		     NULL,
+		     &key_user_tree.rb_node);
+
+	rb_insert_color(&root_key_user.node,
+			&key_user_tree);
+}
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
new file mode 100644
index 000000000..9394d72a7
--- /dev/null
+++ b/security/keys/keyctl.c
@@ -0,0 +1,1817 @@
+/* Userspace key control operations
+ *
+ * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/sched/task.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/key.h>
+#include <linux/keyctl.h>
+#include <linux/fs.h>
+#include <linux/capability.h>
+#include <linux/cred.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/security.h>
+#include <linux/uio.h>
+#include <linux/uaccess.h>
+#include <keys/request_key_auth-type.h>
+#include "internal.h"
+
+#define KEY_MAX_DESC_SIZE 4096
+
+static int key_get_type_from_user(char *type,
+				  const char __user *_type,
+				  unsigned len)
+{
+	int ret;
+
+	ret = strncpy_from_user(type, _type, len);
+	if (ret < 0)
+		return ret;
+	if (ret == 0 || ret >= len)
+		return -EINVAL;
+	if (type[0] == '.')
+		return -EPERM;
+	type[len - 1] = '\0';
+	return 0;
+}
+
+/*
+ * Extract the description of a new key from userspace and either add it as a
+ * new key to the specified keyring or update a matching key in that keyring.
+ *
+ * If the description is NULL or an empty string, the key type is asked to
+ * generate one from the payload.
+ *
+ * The keyring must be writable so that we can attach the key to it.
+ *
+ * If successful, the new key's serial number is returned, otherwise an error
+ * code is returned.
+ */
+SYSCALL_DEFINE5(add_key, const char __user *, _type,
+		const char __user *, _description,
+		const void __user *, _payload,
+		size_t, plen,
+		key_serial_t, ringid)
+{
+	key_ref_t keyring_ref, key_ref;
+	char type[32], *description;
+	void *payload;
+	long ret;
+
+	ret = -EINVAL;
+	if (plen > 1024 * 1024 - 1)
+		goto error;
+
+	/* draw all the data into kernel space */
+	ret = key_get_type_from_user(type, _type, sizeof(type));
+	if (ret < 0)
+		goto error;
+
+	description = NULL;
+	if (_description) {
+		description = strndup_user(_description, KEY_MAX_DESC_SIZE);
+		if (IS_ERR(description)) {
+			ret = PTR_ERR(description);
+			goto error;
+		}
+		if (!*description) {
+			kfree(description);
+			description = NULL;
+		} else if ((description[0] == '.') &&
+			   (strncmp(type, "keyring", 7) == 0)) {
+			ret = -EPERM;
+			goto error2;
+		}
+	}
+
+	/* pull the payload in if one was supplied */
+	payload = NULL;
+
+	if (plen) {
+		ret = -ENOMEM;
+		payload = kvmalloc(plen, GFP_KERNEL);
+		if (!payload)
+			goto error2;
+
+		ret = -EFAULT;
+		if (copy_from_user(payload, _payload, plen) != 0)
+			goto error3;
+	}
+
+	/* find the target keyring (which must be writable) */
+	keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
+		goto error3;
+	}
+
+	/* create or update the requested key and add it to the target
+	 * keyring */
+	key_ref = key_create_or_update(keyring_ref, type, description,
+				       payload, plen, KEY_PERM_UNDEF,
+				       KEY_ALLOC_IN_QUOTA);
+	if (!IS_ERR(key_ref)) {
+		ret = key_ref_to_ptr(key_ref)->serial;
+		key_ref_put(key_ref);
+	}
+	else {
+		ret = PTR_ERR(key_ref);
+	}
+
+	key_ref_put(keyring_ref);
+ error3:
+	kvfree_sensitive(payload, plen);
+ error2:
+	kfree(description);
+ error:
+	return ret;
+}
+
+/*
+ * Search the process keyrings and keyring trees linked from those for a
+ * matching key.  Keyrings must have appropriate Search permission to be
+ * searched.
+ *
+ * If a key is found, it will be attached to the destination keyring if there's
+ * one specified and the serial number of the key will be returned.
+ *
+ * If no key is found, /sbin/request-key will be invoked if _callout_info is
+ * non-NULL in an attempt to create a key.  The _callout_info string will be
+ * passed to /sbin/request-key to aid with completing the request.  If the
+ * _callout_info string is "" then it will be changed to "-".
+ */
+SYSCALL_DEFINE4(request_key, const char __user *, _type,
+		const char __user *, _description,
+		const char __user *, _callout_info,
+		key_serial_t, destringid)
+{
+	struct key_type *ktype;
+	struct key *key;
+	key_ref_t dest_ref;
+	size_t callout_len;
+	char type[32], *description, *callout_info;
+	long ret;
+
+	/* pull the type into kernel space */
+	ret = key_get_type_from_user(type, _type, sizeof(type));
+	if (ret < 0)
+		goto error;
+
+	/* pull the description into kernel space */
+	description = strndup_user(_description, KEY_MAX_DESC_SIZE);
+	if (IS_ERR(description)) {
+		ret = PTR_ERR(description);
+		goto error;
+	}
+
+	/* pull the callout info into kernel space */
+	callout_info = NULL;
+	callout_len = 0;
+	if (_callout_info) {
+		callout_info = strndup_user(_callout_info, PAGE_SIZE);
+		if (IS_ERR(callout_info)) {
+			ret = PTR_ERR(callout_info);
+			goto error2;
+		}
+		callout_len = strlen(callout_info);
+	}
+
+	/* get the destination keyring if specified */
+	dest_ref = NULL;
+	if (destringid) {
+		dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
+					   KEY_NEED_WRITE);
+		if (IS_ERR(dest_ref)) {
+			ret = PTR_ERR(dest_ref);
+			goto error3;
+		}
+	}
+
+	/* find the key type */
+	ktype = key_type_lookup(type);
+	if (IS_ERR(ktype)) {
+		ret = PTR_ERR(ktype);
+		goto error4;
+	}
+
+	/* do the search */
+	key = request_key_and_link(ktype, description, callout_info,
+				   callout_len, NULL, key_ref_to_ptr(dest_ref),
+				   KEY_ALLOC_IN_QUOTA);
+	if (IS_ERR(key)) {
+		ret = PTR_ERR(key);
+		goto error5;
+	}
+
+	/* wait for the key to finish being constructed */
+	ret = wait_for_key_construction(key, 1);
+	if (ret < 0)
+		goto error6;
+
+	ret = key->serial;
+
+error6:
+ 	key_put(key);
+error5:
+	key_type_put(ktype);
+error4:
+	key_ref_put(dest_ref);
+error3:
+	kfree(callout_info);
+error2:
+	kfree(description);
+error:
+	return ret;
+}
+
+/*
+ * Get the ID of the specified process keyring.
+ *
+ * The requested keyring must have search permission to be found.
+ *
+ * If successful, the ID of the requested keyring will be returned.
+ */
+long keyctl_get_keyring_ID(key_serial_t id, int create)
+{
+	key_ref_t key_ref;
+	unsigned long lflags;
+	long ret;
+
+	lflags = create ? KEY_LOOKUP_CREATE : 0;
+	key_ref = lookup_user_key(id, lflags, KEY_NEED_SEARCH);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+	ret = key_ref_to_ptr(key_ref)->serial;
+	key_ref_put(key_ref);
+error:
+	return ret;
+}
+
+/*
+ * Join a (named) session keyring.
+ *
+ * Create and join an anonymous session keyring or join a named session
+ * keyring, creating it if necessary.  A named session keyring must have Search
+ * permission for it to be joined.  Session keyrings without this permit will
+ * be skipped over.  It is not permitted for userspace to create or join
+ * keyrings whose name begin with a dot.
+ *
+ * If successful, the ID of the joined session keyring will be returned.
+ */
+long keyctl_join_session_keyring(const char __user *_name)
+{
+	char *name;
+	long ret;
+
+	/* fetch the name from userspace */
+	name = NULL;
+	if (_name) {
+		name = strndup_user(_name, KEY_MAX_DESC_SIZE);
+		if (IS_ERR(name)) {
+			ret = PTR_ERR(name);
+			goto error;
+		}
+
+		ret = -EPERM;
+		if (name[0] == '.')
+			goto error_name;
+	}
+
+	/* join the session */
+	ret = join_session_keyring(name);
+error_name:
+	kfree(name);
+error:
+	return ret;
+}
+
+/*
+ * Update a key's data payload from the given data.
+ *
+ * The key must grant the caller Write permission and the key type must support
+ * updating for this to work.  A negative key can be positively instantiated
+ * with this call.
+ *
+ * If successful, 0 will be returned.  If the key type does not support
+ * updating, then -EOPNOTSUPP will be returned.
+ */
+long keyctl_update_key(key_serial_t id,
+		       const void __user *_payload,
+		       size_t plen)
+{
+	key_ref_t key_ref;
+	void *payload;
+	long ret;
+
+	ret = -EINVAL;
+	if (plen > PAGE_SIZE)
+		goto error;
+
+	/* pull the payload in if one was supplied */
+	payload = NULL;
+	if (plen) {
+		ret = -ENOMEM;
+		payload = kvmalloc(plen, GFP_KERNEL);
+		if (!payload)
+			goto error;
+
+		ret = -EFAULT;
+		if (copy_from_user(payload, _payload, plen) != 0)
+			goto error2;
+	}
+
+	/* find the target key (which must be writable) */
+	key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error2;
+	}
+
+	/* update the key */
+	ret = key_update(key_ref, payload, plen);
+
+	key_ref_put(key_ref);
+error2:
+	kvfree_sensitive(payload, plen);
+error:
+	return ret;
+}
+
+/*
+ * Revoke a key.
+ *
+ * The key must be grant the caller Write or Setattr permission for this to
+ * work.  The key type should give up its quota claim when revoked.  The key
+ * and any links to the key will be automatically garbage collected after a
+ * certain amount of time (/proc/sys/kernel/keys/gc_delay).
+ *
+ * Keys with KEY_FLAG_KEEP set should not be revoked.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_revoke_key(key_serial_t id)
+{
+	key_ref_t key_ref;
+	struct key *key;
+	long ret;
+
+	key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		if (ret != -EACCES)
+			goto error;
+		key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR);
+		if (IS_ERR(key_ref)) {
+			ret = PTR_ERR(key_ref);
+			goto error;
+		}
+	}
+
+	key = key_ref_to_ptr(key_ref);
+	ret = 0;
+	if (test_bit(KEY_FLAG_KEEP, &key->flags))
+		ret = -EPERM;
+	else
+		key_revoke(key);
+
+	key_ref_put(key_ref);
+error:
+	return ret;
+}
+
+/*
+ * Invalidate a key.
+ *
+ * The key must be grant the caller Invalidate permission for this to work.
+ * The key and any links to the key will be automatically garbage collected
+ * immediately.
+ *
+ * Keys with KEY_FLAG_KEEP set should not be invalidated.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_invalidate_key(key_serial_t id)
+{
+	key_ref_t key_ref;
+	struct key *key;
+	long ret;
+
+	kenter("%d", id);
+
+	key_ref = lookup_user_key(id, 0, KEY_NEED_SEARCH);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+
+		/* Root is permitted to invalidate certain special keys */
+		if (capable(CAP_SYS_ADMIN)) {
+			key_ref = lookup_user_key(id, 0, 0);
+			if (IS_ERR(key_ref))
+				goto error;
+			if (test_bit(KEY_FLAG_ROOT_CAN_INVAL,
+				     &key_ref_to_ptr(key_ref)->flags))
+				goto invalidate;
+			goto error_put;
+		}
+
+		goto error;
+	}
+
+invalidate:
+	key = key_ref_to_ptr(key_ref);
+	ret = 0;
+	if (test_bit(KEY_FLAG_KEEP, &key->flags))
+		ret = -EPERM;
+	else
+		key_invalidate(key);
+error_put:
+	key_ref_put(key_ref);
+error:
+	kleave(" = %ld", ret);
+	return ret;
+}
+
+/*
+ * Clear the specified keyring, creating an empty process keyring if one of the
+ * special keyring IDs is used.
+ *
+ * The keyring must grant the caller Write permission and not have
+ * KEY_FLAG_KEEP set for this to work.  If successful, 0 will be returned.
+ */
+long keyctl_keyring_clear(key_serial_t ringid)
+{
+	key_ref_t keyring_ref;
+	struct key *keyring;
+	long ret;
+
+	keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
+
+		/* Root is permitted to invalidate certain special keyrings */
+		if (capable(CAP_SYS_ADMIN)) {
+			keyring_ref = lookup_user_key(ringid, 0, 0);
+			if (IS_ERR(keyring_ref))
+				goto error;
+			if (test_bit(KEY_FLAG_ROOT_CAN_CLEAR,
+				     &key_ref_to_ptr(keyring_ref)->flags))
+				goto clear;
+			goto error_put;
+		}
+
+		goto error;
+	}
+
+clear:
+	keyring = key_ref_to_ptr(keyring_ref);
+	if (test_bit(KEY_FLAG_KEEP, &keyring->flags))
+		ret = -EPERM;
+	else
+		ret = keyring_clear(keyring);
+error_put:
+	key_ref_put(keyring_ref);
+error:
+	return ret;
+}
+
+/*
+ * Create a link from a keyring to a key if there's no matching key in the
+ * keyring, otherwise replace the link to the matching key with a link to the
+ * new key.
+ *
+ * The key must grant the caller Link permission and the the keyring must grant
+ * the caller Write permission.  Furthermore, if an additional link is created,
+ * the keyring's quota will be extended.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
+{
+	key_ref_t keyring_ref, key_ref;
+	long ret;
+
+	keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
+		goto error;
+	}
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_NEED_LINK);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error2;
+	}
+
+	ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
+
+	key_ref_put(key_ref);
+error2:
+	key_ref_put(keyring_ref);
+error:
+	return ret;
+}
+
+/*
+ * Unlink a key from a keyring.
+ *
+ * The keyring must grant the caller Write permission for this to work; the key
+ * itself need not grant the caller anything.  If the last link to a key is
+ * removed then that key will be scheduled for destruction.
+ *
+ * Keys or keyrings with KEY_FLAG_KEEP set should not be unlinked.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
+{
+	key_ref_t keyring_ref, key_ref;
+	struct key *keyring, *key;
+	long ret;
+
+	keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_WRITE);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
+		goto error;
+	}
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_FOR_UNLINK, 0);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error2;
+	}
+
+	keyring = key_ref_to_ptr(keyring_ref);
+	key = key_ref_to_ptr(key_ref);
+	if (test_bit(KEY_FLAG_KEEP, &keyring->flags) &&
+	    test_bit(KEY_FLAG_KEEP, &key->flags))
+		ret = -EPERM;
+	else
+		ret = key_unlink(keyring, key);
+
+	key_ref_put(key_ref);
+error2:
+	key_ref_put(keyring_ref);
+error:
+	return ret;
+}
+
+/*
+ * Return a description of a key to userspace.
+ *
+ * The key must grant the caller View permission for this to work.
+ *
+ * If there's a buffer, we place up to buflen bytes of data into it formatted
+ * in the following way:
+ *
+ *	type;uid;gid;perm;description<NUL>
+ *
+ * If successful, we return the amount of description available, irrespective
+ * of how much we may have copied into the buffer.
+ */
+long keyctl_describe_key(key_serial_t keyid,
+			 char __user *buffer,
+			 size_t buflen)
+{
+	struct key *key, *instkey;
+	key_ref_t key_ref;
+	char *infobuf;
+	long ret;
+	int desclen, infolen;
+
+	key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW);
+	if (IS_ERR(key_ref)) {
+		/* viewing a key under construction is permitted if we have the
+		 * authorisation token handy */
+		if (PTR_ERR(key_ref) == -EACCES) {
+			instkey = key_get_instantiation_authkey(keyid);
+			if (!IS_ERR(instkey)) {
+				key_put(instkey);
+				key_ref = lookup_user_key(keyid,
+							  KEY_LOOKUP_PARTIAL,
+							  0);
+				if (!IS_ERR(key_ref))
+					goto okay;
+			}
+		}
+
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+okay:
+	key = key_ref_to_ptr(key_ref);
+	desclen = strlen(key->description);
+
+	/* calculate how much information we're going to return */
+	ret = -ENOMEM;
+	infobuf = kasprintf(GFP_KERNEL,
+			    "%s;%d;%d;%08x;",
+			    key->type->name,
+			    from_kuid_munged(current_user_ns(), key->uid),
+			    from_kgid_munged(current_user_ns(), key->gid),
+			    key->perm);
+	if (!infobuf)
+		goto error2;
+	infolen = strlen(infobuf);
+	ret = infolen + desclen + 1;
+
+	/* consider returning the data */
+	if (buffer && buflen >= ret) {
+		if (copy_to_user(buffer, infobuf, infolen) != 0 ||
+		    copy_to_user(buffer + infolen, key->description,
+				 desclen + 1) != 0)
+			ret = -EFAULT;
+	}
+
+	kfree(infobuf);
+error2:
+	key_ref_put(key_ref);
+error:
+	return ret;
+}
+
+/*
+ * Search the specified keyring and any keyrings it links to for a matching
+ * key.  Only keyrings that grant the caller Search permission will be searched
+ * (this includes the starting keyring).  Only keys with Search permission can
+ * be found.
+ *
+ * If successful, the found key will be linked to the destination keyring if
+ * supplied and the key has Link permission, and the found key ID will be
+ * returned.
+ */
+long keyctl_keyring_search(key_serial_t ringid,
+			   const char __user *_type,
+			   const char __user *_description,
+			   key_serial_t destringid)
+{
+	struct key_type *ktype;
+	key_ref_t keyring_ref, key_ref, dest_ref;
+	char type[32], *description;
+	long ret;
+
+	/* pull the type and description into kernel space */
+	ret = key_get_type_from_user(type, _type, sizeof(type));
+	if (ret < 0)
+		goto error;
+
+	description = strndup_user(_description, KEY_MAX_DESC_SIZE);
+	if (IS_ERR(description)) {
+		ret = PTR_ERR(description);
+		goto error;
+	}
+
+	/* get the keyring at which to begin the search */
+	keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_SEARCH);
+	if (IS_ERR(keyring_ref)) {
+		ret = PTR_ERR(keyring_ref);
+		goto error2;
+	}
+
+	/* get the destination keyring if specified */
+	dest_ref = NULL;
+	if (destringid) {
+		dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
+					   KEY_NEED_WRITE);
+		if (IS_ERR(dest_ref)) {
+			ret = PTR_ERR(dest_ref);
+			goto error3;
+		}
+	}
+
+	/* find the key type */
+	ktype = key_type_lookup(type);
+	if (IS_ERR(ktype)) {
+		ret = PTR_ERR(ktype);
+		goto error4;
+	}
+
+	/* do the search */
+	key_ref = keyring_search(keyring_ref, ktype, description);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+
+		/* treat lack or presence of a negative key the same */
+		if (ret == -EAGAIN)
+			ret = -ENOKEY;
+		goto error5;
+	}
+
+	/* link the resulting key to the destination keyring if we can */
+	if (dest_ref) {
+		ret = key_permission(key_ref, KEY_NEED_LINK);
+		if (ret < 0)
+			goto error6;
+
+		ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
+		if (ret < 0)
+			goto error6;
+	}
+
+	ret = key_ref_to_ptr(key_ref)->serial;
+
+error6:
+	key_ref_put(key_ref);
+error5:
+	key_type_put(ktype);
+error4:
+	key_ref_put(dest_ref);
+error3:
+	key_ref_put(keyring_ref);
+error2:
+	kfree(description);
+error:
+	return ret;
+}
+
+/*
+ * Call the read method
+ */
+static long __keyctl_read_key(struct key *key, char *buffer, size_t buflen)
+{
+	long ret;
+
+	down_read(&key->sem);
+	ret = key_validate(key);
+	if (ret == 0)
+		ret = key->type->read(key, buffer, buflen);
+	up_read(&key->sem);
+	return ret;
+}
+
+/*
+ * Read a key's payload.
+ *
+ * The key must either grant the caller Read permission, or it must grant the
+ * caller Search permission when searched for from the process keyrings.
+ *
+ * If successful, we place up to buflen bytes of data into the buffer, if one
+ * is provided, and return the amount of data that is available in the key,
+ * irrespective of how much we copied into the buffer.
+ */
+long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
+{
+	struct key *key;
+	key_ref_t key_ref;
+	long ret;
+	char *key_data = NULL;
+	size_t key_data_len;
+
+	/* find the key first */
+	key_ref = lookup_user_key(keyid, 0, 0);
+	if (IS_ERR(key_ref)) {
+		ret = -ENOKEY;
+		goto out;
+	}
+
+	key = key_ref_to_ptr(key_ref);
+
+	ret = key_read_state(key);
+	if (ret < 0)
+		goto key_put_out; /* Negatively instantiated */
+
+	/* see if we can read it directly */
+	ret = key_permission(key_ref, KEY_NEED_READ);
+	if (ret == 0)
+		goto can_read_key;
+	if (ret != -EACCES)
+		goto key_put_out;
+
+	/* we can't; see if it's searchable from this process's keyrings
+	 * - we automatically take account of the fact that it may be
+	 *   dangling off an instantiation key
+	 */
+	if (!is_key_possessed(key_ref)) {
+		ret = -EACCES;
+		goto key_put_out;
+	}
+
+	/* the key is probably readable - now try to read it */
+can_read_key:
+	if (!key->type->read) {
+		ret = -EOPNOTSUPP;
+		goto key_put_out;
+	}
+
+	if (!buffer || !buflen) {
+		/* Get the key length from the read method */
+		ret = __keyctl_read_key(key, NULL, 0);
+		goto key_put_out;
+	}
+
+	/*
+	 * Read the data with the semaphore held (since we might sleep)
+	 * to protect against the key being updated or revoked.
+	 *
+	 * Allocating a temporary buffer to hold the keys before
+	 * transferring them to user buffer to avoid potential
+	 * deadlock involving page fault and mmap_sem.
+	 *
+	 * key_data_len = (buflen <= PAGE_SIZE)
+	 *		? buflen : actual length of key data
+	 *
+	 * This prevents allocating arbitrary large buffer which can
+	 * be much larger than the actual key length. In the latter case,
+	 * at least 2 passes of this loop is required.
+	 */
+	key_data_len = (buflen <= PAGE_SIZE) ? buflen : 0;
+	for (;;) {
+		if (key_data_len) {
+			key_data = kvmalloc(key_data_len, GFP_KERNEL);
+			if (!key_data) {
+				ret = -ENOMEM;
+				goto key_put_out;
+			}
+		}
+
+		ret = __keyctl_read_key(key, key_data, key_data_len);
+
+		/*
+		 * Read methods will just return the required length without
+		 * any copying if the provided length isn't large enough.
+		 */
+		if (ret <= 0 || ret > buflen)
+			break;
+
+		/*
+		 * The key may change (unlikely) in between 2 consecutive
+		 * __keyctl_read_key() calls. In this case, we reallocate
+		 * a larger buffer and redo the key read when
+		 * key_data_len < ret <= buflen.
+		 */
+		if (ret > key_data_len) {
+			if (unlikely(key_data))
+				kvfree_sensitive(key_data, key_data_len);
+			key_data_len = ret;
+			continue;	/* Allocate buffer */
+		}
+
+		if (copy_to_user(buffer, key_data, ret))
+			ret = -EFAULT;
+		break;
+	}
+	kvfree_sensitive(key_data, key_data_len);
+
+key_put_out:
+	key_put(key);
+out:
+	return ret;
+}
+
+/*
+ * Change the ownership of a key
+ *
+ * The key must grant the caller Setattr permission for this to work, though
+ * the key need not be fully instantiated yet.  For the UID to be changed, or
+ * for the GID to be changed to a group the caller is not a member of, the
+ * caller must have sysadmin capability.  If either uid or gid is -1 then that
+ * attribute is not changed.
+ *
+ * If the UID is to be changed, the new user must have sufficient quota to
+ * accept the key.  The quota deduction will be removed from the old user to
+ * the new user should the attribute be changed.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
+{
+	struct key_user *newowner, *zapowner = NULL;
+	struct key *key;
+	key_ref_t key_ref;
+	long ret;
+	kuid_t uid;
+	kgid_t gid;
+
+	uid = make_kuid(current_user_ns(), user);
+	gid = make_kgid(current_user_ns(), group);
+	ret = -EINVAL;
+	if ((user != (uid_t) -1) && !uid_valid(uid))
+		goto error;
+	if ((group != (gid_t) -1) && !gid_valid(gid))
+		goto error;
+
+	ret = 0;
+	if (user == (uid_t) -1 && group == (gid_t) -1)
+		goto error;
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+				  KEY_NEED_SETATTR);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+	key = key_ref_to_ptr(key_ref);
+
+	/* make the changes with the locks held to prevent chown/chown races */
+	ret = -EACCES;
+	down_write(&key->sem);
+
+	if (!capable(CAP_SYS_ADMIN)) {
+		/* only the sysadmin can chown a key to some other UID */
+		if (user != (uid_t) -1 && !uid_eq(key->uid, uid))
+			goto error_put;
+
+		/* only the sysadmin can set the key's GID to a group other
+		 * than one of those that the current process subscribes to */
+		if (group != (gid_t) -1 && !gid_eq(gid, key->gid) && !in_group_p(gid))
+			goto error_put;
+	}
+
+	/* change the UID */
+	if (user != (uid_t) -1 && !uid_eq(uid, key->uid)) {
+		ret = -ENOMEM;
+		newowner = key_user_lookup(uid);
+		if (!newowner)
+			goto error_put;
+
+		/* transfer the quota burden to the new user */
+		if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+			unsigned maxkeys = uid_eq(uid, GLOBAL_ROOT_UID) ?
+				key_quota_root_maxkeys : key_quota_maxkeys;
+			unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ?
+				key_quota_root_maxbytes : key_quota_maxbytes;
+
+			spin_lock(&newowner->lock);
+			if (newowner->qnkeys + 1 > maxkeys ||
+			    newowner->qnbytes + key->quotalen > maxbytes ||
+			    newowner->qnbytes + key->quotalen <
+			    newowner->qnbytes)
+				goto quota_overrun;
+
+			newowner->qnkeys++;
+			newowner->qnbytes += key->quotalen;
+			spin_unlock(&newowner->lock);
+
+			spin_lock(&key->user->lock);
+			key->user->qnkeys--;
+			key->user->qnbytes -= key->quotalen;
+			spin_unlock(&key->user->lock);
+		}
+
+		atomic_dec(&key->user->nkeys);
+		atomic_inc(&newowner->nkeys);
+
+		if (key->state != KEY_IS_UNINSTANTIATED) {
+			atomic_dec(&key->user->nikeys);
+			atomic_inc(&newowner->nikeys);
+		}
+
+		zapowner = key->user;
+		key->user = newowner;
+		key->uid = uid;
+	}
+
+	/* change the GID */
+	if (group != (gid_t) -1)
+		key->gid = gid;
+
+	ret = 0;
+
+error_put:
+	up_write(&key->sem);
+	key_put(key);
+	if (zapowner)
+		key_user_put(zapowner);
+error:
+	return ret;
+
+quota_overrun:
+	spin_unlock(&newowner->lock);
+	zapowner = newowner;
+	ret = -EDQUOT;
+	goto error_put;
+}
+
+/*
+ * Change the permission mask on a key.
+ *
+ * The key must grant the caller Setattr permission for this to work, though
+ * the key need not be fully instantiated yet.  If the caller does not have
+ * sysadmin capability, it may only change the permission on keys that it owns.
+ */
+long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
+{
+	struct key *key;
+	key_ref_t key_ref;
+	long ret;
+
+	ret = -EINVAL;
+	if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
+		goto error;
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+				  KEY_NEED_SETATTR);
+	if (IS_ERR(key_ref)) {
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+	key = key_ref_to_ptr(key_ref);
+
+	/* make the changes with the locks held to prevent chown/chmod races */
+	ret = -EACCES;
+	down_write(&key->sem);
+
+	/* if we're not the sysadmin, we can only change a key that we own */
+	if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) {
+		key->perm = perm;
+		ret = 0;
+	}
+
+	up_write(&key->sem);
+	key_put(key);
+error:
+	return ret;
+}
+
+/*
+ * Get the destination keyring for instantiation and check that the caller has
+ * Write permission on it.
+ */
+static long get_instantiation_keyring(key_serial_t ringid,
+				      struct request_key_auth *rka,
+				      struct key **_dest_keyring)
+{
+	key_ref_t dkref;
+
+	*_dest_keyring = NULL;
+
+	/* just return a NULL pointer if we weren't asked to make a link */
+	if (ringid == 0)
+		return 0;
+
+	/* if a specific keyring is nominated by ID, then use that */
+	if (ringid > 0) {
+		dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+		if (IS_ERR(dkref))
+			return PTR_ERR(dkref);
+		*_dest_keyring = key_ref_to_ptr(dkref);
+		return 0;
+	}
+
+	if (ringid == KEY_SPEC_REQKEY_AUTH_KEY)
+		return -EINVAL;
+
+	/* otherwise specify the destination keyring recorded in the
+	 * authorisation key (any KEY_SPEC_*_KEYRING) */
+	if (ringid >= KEY_SPEC_REQUESTOR_KEYRING) {
+		*_dest_keyring = key_get(rka->dest_keyring);
+		return 0;
+	}
+
+	return -ENOKEY;
+}
+
+/*
+ * Change the request_key authorisation key on the current process.
+ */
+static int keyctl_change_reqkey_auth(struct key *key)
+{
+	struct cred *new;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	key_put(new->request_key_auth);
+	new->request_key_auth = key_get(key);
+
+	return commit_creds(new);
+}
+
+/*
+ * Instantiate a key with the specified payload and link the key into the
+ * destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key_common(key_serial_t id,
+				   struct iov_iter *from,
+				   key_serial_t ringid)
+{
+	const struct cred *cred = current_cred();
+	struct request_key_auth *rka;
+	struct key *instkey, *dest_keyring;
+	size_t plen = from ? iov_iter_count(from) : 0;
+	void *payload;
+	long ret;
+
+	kenter("%d,,%zu,%d", id, plen, ringid);
+
+	if (!plen)
+		from = NULL;
+
+	ret = -EINVAL;
+	if (plen > 1024 * 1024 - 1)
+		goto error;
+
+	/* the appropriate instantiation authorisation key must have been
+	 * assumed before calling this */
+	ret = -EPERM;
+	instkey = cred->request_key_auth;
+	if (!instkey)
+		goto error;
+
+	rka = instkey->payload.data[0];
+	if (rka->target_key->serial != id)
+		goto error;
+
+	/* pull the payload in if one was supplied */
+	payload = NULL;
+
+	if (from) {
+		ret = -ENOMEM;
+		payload = kvmalloc(plen, GFP_KERNEL);
+		if (!payload)
+			goto error;
+
+		ret = -EFAULT;
+		if (!copy_from_iter_full(payload, plen, from))
+			goto error2;
+	}
+
+	/* find the destination keyring amongst those belonging to the
+	 * requesting task */
+	ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+	if (ret < 0)
+		goto error2;
+
+	/* instantiate the key and link it into a keyring */
+	ret = key_instantiate_and_link(rka->target_key, payload, plen,
+				       dest_keyring, instkey);
+
+	key_put(dest_keyring);
+
+	/* discard the assumed authority if it's just been disabled by
+	 * instantiation of the key */
+	if (ret == 0)
+		keyctl_change_reqkey_auth(NULL);
+
+error2:
+	kvfree_sensitive(payload, plen);
+error:
+	return ret;
+}
+
+/*
+ * Instantiate a key with the specified payload and link the key into the
+ * destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key(key_serial_t id,
+			    const void __user *_payload,
+			    size_t plen,
+			    key_serial_t ringid)
+{
+	if (_payload && plen) {
+		struct iovec iov;
+		struct iov_iter from;
+		int ret;
+
+		ret = import_single_range(WRITE, (void __user *)_payload, plen,
+					  &iov, &from);
+		if (unlikely(ret))
+			return ret;
+
+		return keyctl_instantiate_key_common(id, &from, ringid);
+	}
+
+	return keyctl_instantiate_key_common(id, NULL, ringid);
+}
+
+/*
+ * Instantiate a key with the specified multipart payload and link the key into
+ * the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key_iov(key_serial_t id,
+				const struct iovec __user *_payload_iov,
+				unsigned ioc,
+				key_serial_t ringid)
+{
+	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+	struct iov_iter from;
+	long ret;
+
+	if (!_payload_iov)
+		ioc = 0;
+
+	ret = import_iovec(WRITE, _payload_iov, ioc,
+				    ARRAY_SIZE(iovstack), &iov, &from);
+	if (ret < 0)
+		return ret;
+	ret = keyctl_instantiate_key_common(id, &from, ringid);
+	kfree(iov);
+	return ret;
+}
+
+/*
+ * Negatively instantiate the key with the given timeout (in seconds) and link
+ * the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * The key and any links to the key will be automatically garbage collected
+ * after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return -ENOKEY until the negative key expires.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
+{
+	return keyctl_reject_key(id, timeout, ENOKEY, ringid);
+}
+
+/*
+ * Negatively instantiate the key with the given timeout (in seconds) and error
+ * code and link the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority).  No other permissions are required.
+ *
+ * The key and any links to the key will be automatically garbage collected
+ * after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return the specified error code until the negative key expires.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_reject_key(key_serial_t id, unsigned timeout, unsigned error,
+		       key_serial_t ringid)
+{
+	const struct cred *cred = current_cred();
+	struct request_key_auth *rka;
+	struct key *instkey, *dest_keyring;
+	long ret;
+
+	kenter("%d,%u,%u,%d", id, timeout, error, ringid);
+
+	/* must be a valid error code and mustn't be a kernel special */
+	if (error <= 0 ||
+	    error >= MAX_ERRNO ||
+	    error == ERESTARTSYS ||
+	    error == ERESTARTNOINTR ||
+	    error == ERESTARTNOHAND ||
+	    error == ERESTART_RESTARTBLOCK)
+		return -EINVAL;
+
+	/* the appropriate instantiation authorisation key must have been
+	 * assumed before calling this */
+	ret = -EPERM;
+	instkey = cred->request_key_auth;
+	if (!instkey)
+		goto error;
+
+	rka = instkey->payload.data[0];
+	if (rka->target_key->serial != id)
+		goto error;
+
+	/* find the destination keyring if present (which must also be
+	 * writable) */
+	ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+	if (ret < 0)
+		goto error;
+
+	/* instantiate the key and link it into a keyring */
+	ret = key_reject_and_link(rka->target_key, timeout, error,
+				  dest_keyring, instkey);
+
+	key_put(dest_keyring);
+
+	/* discard the assumed authority if it's just been disabled by
+	 * instantiation of the key */
+	if (ret == 0)
+		keyctl_change_reqkey_auth(NULL);
+
+error:
+	return ret;
+}
+
+/*
+ * Read or set the default keyring in which request_key() will cache keys and
+ * return the old setting.
+ *
+ * If a thread or process keyring is specified then it will be created if it
+ * doesn't yet exist.  The old setting will be returned if successful.
+ */
+long keyctl_set_reqkey_keyring(int reqkey_defl)
+{
+	struct cred *new;
+	int ret, old_setting;
+
+	old_setting = current_cred_xxx(jit_keyring);
+
+	if (reqkey_defl == KEY_REQKEY_DEFL_NO_CHANGE)
+		return old_setting;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	switch (reqkey_defl) {
+	case KEY_REQKEY_DEFL_THREAD_KEYRING:
+		ret = install_thread_keyring_to_cred(new);
+		if (ret < 0)
+			goto error;
+		goto set;
+
+	case KEY_REQKEY_DEFL_PROCESS_KEYRING:
+		ret = install_process_keyring_to_cred(new);
+		if (ret < 0)
+			goto error;
+		goto set;
+
+	case KEY_REQKEY_DEFL_DEFAULT:
+	case KEY_REQKEY_DEFL_SESSION_KEYRING:
+	case KEY_REQKEY_DEFL_USER_KEYRING:
+	case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
+	case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+		goto set;
+
+	case KEY_REQKEY_DEFL_NO_CHANGE:
+	case KEY_REQKEY_DEFL_GROUP_KEYRING:
+	default:
+		ret = -EINVAL;
+		goto error;
+	}
+
+set:
+	new->jit_keyring = reqkey_defl;
+	commit_creds(new);
+	return old_setting;
+error:
+	abort_creds(new);
+	return ret;
+}
+
+/*
+ * Set or clear the timeout on a key.
+ *
+ * Either the key must grant the caller Setattr permission or else the caller
+ * must hold an instantiation authorisation token for the key.
+ *
+ * The timeout is either 0 to clear the timeout, or a number of seconds from
+ * the current time.  The key and any links to the key will be automatically
+ * garbage collected after the timeout expires.
+ *
+ * Keys with KEY_FLAG_KEEP set should not be timed out.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_set_timeout(key_serial_t id, unsigned timeout)
+{
+	struct key *key, *instkey;
+	key_ref_t key_ref;
+	long ret;
+
+	key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+				  KEY_NEED_SETATTR);
+	if (IS_ERR(key_ref)) {
+		/* setting the timeout on a key under construction is permitted
+		 * if we have the authorisation token handy */
+		if (PTR_ERR(key_ref) == -EACCES) {
+			instkey = key_get_instantiation_authkey(id);
+			if (!IS_ERR(instkey)) {
+				key_put(instkey);
+				key_ref = lookup_user_key(id,
+							  KEY_LOOKUP_PARTIAL,
+							  0);
+				if (!IS_ERR(key_ref))
+					goto okay;
+			}
+		}
+
+		ret = PTR_ERR(key_ref);
+		goto error;
+	}
+
+okay:
+	key = key_ref_to_ptr(key_ref);
+	ret = 0;
+	if (test_bit(KEY_FLAG_KEEP, &key->flags))
+		ret = -EPERM;
+	else
+		key_set_timeout(key, timeout);
+	key_put(key);
+
+error:
+	return ret;
+}
+
+/*
+ * Assume (or clear) the authority to instantiate the specified key.
+ *
+ * This sets the authoritative token currently in force for key instantiation.
+ * This must be done for a key to be instantiated.  It has the effect of making
+ * available all the keys from the caller of the request_key() that created a
+ * key to request_key() calls made by the caller of this function.
+ *
+ * The caller must have the instantiation key in their process keyrings with a
+ * Search permission grant available to the caller.
+ *
+ * If the ID given is 0, then the setting will be cleared and 0 returned.
+ *
+ * If the ID given has a matching an authorisation key, then that key will be
+ * set and its ID will be returned.  The authorisation key can be read to get
+ * the callout information passed to request_key().
+ */
+long keyctl_assume_authority(key_serial_t id)
+{
+	struct key *authkey;
+	long ret;
+
+	/* special key IDs aren't permitted */
+	ret = -EINVAL;
+	if (id < 0)
+		goto error;
+
+	/* we divest ourselves of authority if given an ID of 0 */
+	if (id == 0) {
+		ret = keyctl_change_reqkey_auth(NULL);
+		goto error;
+	}
+
+	/* attempt to assume the authority temporarily granted to us whilst we
+	 * instantiate the specified key
+	 * - the authorisation key must be in the current task's keyrings
+	 *   somewhere
+	 */
+	authkey = key_get_instantiation_authkey(id);
+	if (IS_ERR(authkey)) {
+		ret = PTR_ERR(authkey);
+		goto error;
+	}
+
+	ret = keyctl_change_reqkey_auth(authkey);
+	if (ret == 0)
+		ret = authkey->serial;
+	key_put(authkey);
+error:
+	return ret;
+}
+
+/*
+ * Get a key's the LSM security label.
+ *
+ * The key must grant the caller View permission for this to work.
+ *
+ * If there's a buffer, then up to buflen bytes of data will be placed into it.
+ *
+ * If successful, the amount of information available will be returned,
+ * irrespective of how much was copied (including the terminal NUL).
+ */
+long keyctl_get_security(key_serial_t keyid,
+			 char __user *buffer,
+			 size_t buflen)
+{
+	struct key *key, *instkey;
+	key_ref_t key_ref;
+	char *context;
+	long ret;
+
+	key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW);
+	if (IS_ERR(key_ref)) {
+		if (PTR_ERR(key_ref) != -EACCES)
+			return PTR_ERR(key_ref);
+
+		/* viewing a key under construction is also permitted if we
+		 * have the authorisation token handy */
+		instkey = key_get_instantiation_authkey(keyid);
+		if (IS_ERR(instkey))
+			return PTR_ERR(instkey);
+		key_put(instkey);
+
+		key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, 0);
+		if (IS_ERR(key_ref))
+			return PTR_ERR(key_ref);
+	}
+
+	key = key_ref_to_ptr(key_ref);
+	ret = security_key_getsecurity(key, &context);
+	if (ret == 0) {
+		/* if no information was returned, give userspace an empty
+		 * string */
+		ret = 1;
+		if (buffer && buflen > 0 &&
+		    copy_to_user(buffer, "", 1) != 0)
+			ret = -EFAULT;
+	} else if (ret > 0) {
+		/* return as much data as there's room for */
+		if (buffer && buflen > 0) {
+			if (buflen > ret)
+				buflen = ret;
+
+			if (copy_to_user(buffer, context, buflen) != 0)
+				ret = -EFAULT;
+		}
+
+		kfree(context);
+	}
+
+	key_ref_put(key_ref);
+	return ret;
+}
+
+/*
+ * Attempt to install the calling process's session keyring on the process's
+ * parent process.
+ *
+ * The keyring must exist and must grant the caller LINK permission, and the
+ * parent process must be single-threaded and must have the same effective
+ * ownership as this process and mustn't be SUID/SGID.
+ *
+ * The keyring will be emplaced on the parent when it next resumes userspace.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_session_to_parent(void)
+{
+	struct task_struct *me, *parent;
+	const struct cred *mycred, *pcred;
+	struct callback_head *newwork, *oldwork;
+	key_ref_t keyring_r;
+	struct cred *cred;
+	int ret;
+
+	keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_NEED_LINK);
+	if (IS_ERR(keyring_r))
+		return PTR_ERR(keyring_r);
+
+	ret = -ENOMEM;
+
+	/* our parent is going to need a new cred struct, a new tgcred struct
+	 * and new security data, so we allocate them here to prevent ENOMEM in
+	 * our parent */
+	cred = cred_alloc_blank();
+	if (!cred)
+		goto error_keyring;
+	newwork = &cred->rcu;
+
+	cred->session_keyring = key_ref_to_ptr(keyring_r);
+	keyring_r = NULL;
+	init_task_work(newwork, key_change_session_keyring);
+
+	me = current;
+	rcu_read_lock();
+	write_lock_irq(&tasklist_lock);
+
+	ret = -EPERM;
+	oldwork = NULL;
+	parent = me->real_parent;
+
+	/* the parent mustn't be init and mustn't be a kernel thread */
+	if (parent->pid <= 1 || !parent->mm)
+		goto unlock;
+
+	/* the parent must be single threaded */
+	if (!thread_group_empty(parent))
+		goto unlock;
+
+	/* the parent and the child must have different session keyrings or
+	 * there's no point */
+	mycred = current_cred();
+	pcred = __task_cred(parent);
+	if (mycred == pcred ||
+	    mycred->session_keyring == pcred->session_keyring) {
+		ret = 0;
+		goto unlock;
+	}
+
+	/* the parent must have the same effective ownership and mustn't be
+	 * SUID/SGID */
+	if (!uid_eq(pcred->uid,	 mycred->euid) ||
+	    !uid_eq(pcred->euid, mycred->euid) ||
+	    !uid_eq(pcred->suid, mycred->euid) ||
+	    !gid_eq(pcred->gid,	 mycred->egid) ||
+	    !gid_eq(pcred->egid, mycred->egid) ||
+	    !gid_eq(pcred->sgid, mycred->egid))
+		goto unlock;
+
+	/* the keyrings must have the same UID */
+	if ((pcred->session_keyring &&
+	     !uid_eq(pcred->session_keyring->uid, mycred->euid)) ||
+	    !uid_eq(mycred->session_keyring->uid, mycred->euid))
+		goto unlock;
+
+	/* cancel an already pending keyring replacement */
+	oldwork = task_work_cancel(parent, key_change_session_keyring);
+
+	/* the replacement session keyring is applied just prior to userspace
+	 * restarting */
+	ret = task_work_add(parent, newwork, true);
+	if (!ret)
+		newwork = NULL;
+unlock:
+	write_unlock_irq(&tasklist_lock);
+	rcu_read_unlock();
+	if (oldwork)
+		put_cred(container_of(oldwork, struct cred, rcu));
+	if (newwork)
+		put_cred(cred);
+	return ret;
+
+error_keyring:
+	key_ref_put(keyring_r);
+	return ret;
+}
+
+/*
+ * Apply a restriction to a given keyring.
+ *
+ * The caller must have Setattr permission to change keyring restrictions.
+ *
+ * The requested type name may be a NULL pointer to reject all attempts
+ * to link to the keyring.  In this case, _restriction must also be NULL.
+ * Otherwise, both _type and _restriction must be non-NULL.
+ *
+ * Returns 0 if successful.
+ */
+long keyctl_restrict_keyring(key_serial_t id, const char __user *_type,
+			     const char __user *_restriction)
+{
+	key_ref_t key_ref;
+	char type[32];
+	char *restriction = NULL;
+	long ret;
+
+	key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR);
+	if (IS_ERR(key_ref))
+		return PTR_ERR(key_ref);
+
+	ret = -EINVAL;
+	if (_type) {
+		if (!_restriction)
+			goto error;
+
+		ret = key_get_type_from_user(type, _type, sizeof(type));
+		if (ret < 0)
+			goto error;
+
+		restriction = strndup_user(_restriction, PAGE_SIZE);
+		if (IS_ERR(restriction)) {
+			ret = PTR_ERR(restriction);
+			goto error;
+		}
+	} else {
+		if (_restriction)
+			goto error;
+	}
+
+	ret = keyring_restrict(key_ref, _type ? type : NULL, restriction);
+	kfree(restriction);
+error:
+	key_ref_put(key_ref);
+	return ret;
+}
+
+/*
+ * The key control system call
+ */
+SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
+		unsigned long, arg4, unsigned long, arg5)
+{
+	switch (option) {
+	case KEYCTL_GET_KEYRING_ID:
+		return keyctl_get_keyring_ID((key_serial_t) arg2,
+					     (int) arg3);
+
+	case KEYCTL_JOIN_SESSION_KEYRING:
+		return keyctl_join_session_keyring((const char __user *) arg2);
+
+	case KEYCTL_UPDATE:
+		return keyctl_update_key((key_serial_t) arg2,
+					 (const void __user *) arg3,
+					 (size_t) arg4);
+
+	case KEYCTL_REVOKE:
+		return keyctl_revoke_key((key_serial_t) arg2);
+
+	case KEYCTL_DESCRIBE:
+		return keyctl_describe_key((key_serial_t) arg2,
+					   (char __user *) arg3,
+					   (unsigned) arg4);
+
+	case KEYCTL_CLEAR:
+		return keyctl_keyring_clear((key_serial_t) arg2);
+
+	case KEYCTL_LINK:
+		return keyctl_keyring_link((key_serial_t) arg2,
+					   (key_serial_t) arg3);
+
+	case KEYCTL_UNLINK:
+		return keyctl_keyring_unlink((key_serial_t) arg2,
+					     (key_serial_t) arg3);
+
+	case KEYCTL_SEARCH:
+		return keyctl_keyring_search((key_serial_t) arg2,
+					     (const char __user *) arg3,
+					     (const char __user *) arg4,
+					     (key_serial_t) arg5);
+
+	case KEYCTL_READ:
+		return keyctl_read_key((key_serial_t) arg2,
+				       (char __user *) arg3,
+				       (size_t) arg4);
+
+	case KEYCTL_CHOWN:
+		return keyctl_chown_key((key_serial_t) arg2,
+					(uid_t) arg3,
+					(gid_t) arg4);
+
+	case KEYCTL_SETPERM:
+		return keyctl_setperm_key((key_serial_t) arg2,
+					  (key_perm_t) arg3);
+
+	case KEYCTL_INSTANTIATE:
+		return keyctl_instantiate_key((key_serial_t) arg2,
+					      (const void __user *) arg3,
+					      (size_t) arg4,
+					      (key_serial_t) arg5);
+
+	case KEYCTL_NEGATE:
+		return keyctl_negate_key((key_serial_t) arg2,
+					 (unsigned) arg3,
+					 (key_serial_t) arg4);
+
+	case KEYCTL_SET_REQKEY_KEYRING:
+		return keyctl_set_reqkey_keyring(arg2);
+
+	case KEYCTL_SET_TIMEOUT:
+		return keyctl_set_timeout((key_serial_t) arg2,
+					  (unsigned) arg3);
+
+	case KEYCTL_ASSUME_AUTHORITY:
+		return keyctl_assume_authority((key_serial_t) arg2);
+
+	case KEYCTL_GET_SECURITY:
+		return keyctl_get_security((key_serial_t) arg2,
+					   (char __user *) arg3,
+					   (size_t) arg4);
+
+	case KEYCTL_SESSION_TO_PARENT:
+		return keyctl_session_to_parent();
+
+	case KEYCTL_REJECT:
+		return keyctl_reject_key((key_serial_t) arg2,
+					 (unsigned) arg3,
+					 (unsigned) arg4,
+					 (key_serial_t) arg5);
+
+	case KEYCTL_INSTANTIATE_IOV:
+		return keyctl_instantiate_key_iov(
+			(key_serial_t) arg2,
+			(const struct iovec __user *) arg3,
+			(unsigned) arg4,
+			(key_serial_t) arg5);
+
+	case KEYCTL_INVALIDATE:
+		return keyctl_invalidate_key((key_serial_t) arg2);
+
+	case KEYCTL_GET_PERSISTENT:
+		return keyctl_get_persistent((uid_t)arg2, (key_serial_t)arg3);
+
+	case KEYCTL_DH_COMPUTE:
+		return keyctl_dh_compute((struct keyctl_dh_params __user *) arg2,
+					 (char __user *) arg3, (size_t) arg4,
+					 (struct keyctl_kdf_params __user *) arg5);
+
+	case KEYCTL_RESTRICT_KEYRING:
+		return keyctl_restrict_keyring((key_serial_t) arg2,
+					       (const char __user *) arg3,
+					       (const char __user *) arg4);
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
new file mode 100644
index 000000000..e8f236602
--- /dev/null
+++ b/security/keys/keyring.c
@@ -0,0 +1,1580 @@
+/* Keyring handling
+ *
+ * Copyright (C) 2004-2005, 2008, 2013 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/seq_file.h>
+#include <linux/err.h>
+#include <keys/keyring-type.h>
+#include <keys/user-type.h>
+#include <linux/assoc_array_priv.h>
+#include <linux/uaccess.h>
+#include "internal.h"
+
+/*
+ * When plumbing the depths of the key tree, this sets a hard limit
+ * set on how deep we're willing to go.
+ */
+#define KEYRING_SEARCH_MAX_DEPTH 6
+
+/*
+ * We keep all named keyrings in a hash to speed looking them up.
+ */
+#define KEYRING_NAME_HASH_SIZE	(1 << 5)
+
+/*
+ * We mark pointers we pass to the associative array with bit 1 set if
+ * they're keyrings and clear otherwise.
+ */
+#define KEYRING_PTR_SUBTYPE	0x2UL
+
+static inline bool keyring_ptr_is_keyring(const struct assoc_array_ptr *x)
+{
+	return (unsigned long)x & KEYRING_PTR_SUBTYPE;
+}
+static inline struct key *keyring_ptr_to_key(const struct assoc_array_ptr *x)
+{
+	void *object = assoc_array_ptr_to_leaf(x);
+	return (struct key *)((unsigned long)object & ~KEYRING_PTR_SUBTYPE);
+}
+static inline void *keyring_key_to_ptr(struct key *key)
+{
+	if (key->type == &key_type_keyring)
+		return (void *)((unsigned long)key | KEYRING_PTR_SUBTYPE);
+	return key;
+}
+
+static struct list_head	keyring_name_hash[KEYRING_NAME_HASH_SIZE];
+static DEFINE_RWLOCK(keyring_name_lock);
+
+static inline unsigned keyring_hash(const char *desc)
+{
+	unsigned bucket = 0;
+
+	for (; *desc; desc++)
+		bucket += (unsigned char)*desc;
+
+	return bucket & (KEYRING_NAME_HASH_SIZE - 1);
+}
+
+/*
+ * The keyring key type definition.  Keyrings are simply keys of this type and
+ * can be treated as ordinary keys in addition to having their own special
+ * operations.
+ */
+static int keyring_preparse(struct key_preparsed_payload *prep);
+static void keyring_free_preparse(struct key_preparsed_payload *prep);
+static int keyring_instantiate(struct key *keyring,
+			       struct key_preparsed_payload *prep);
+static void keyring_revoke(struct key *keyring);
+static void keyring_destroy(struct key *keyring);
+static void keyring_describe(const struct key *keyring, struct seq_file *m);
+static long keyring_read(const struct key *keyring,
+			 char __user *buffer, size_t buflen);
+
+struct key_type key_type_keyring = {
+	.name		= "keyring",
+	.def_datalen	= 0,
+	.preparse	= keyring_preparse,
+	.free_preparse	= keyring_free_preparse,
+	.instantiate	= keyring_instantiate,
+	.revoke		= keyring_revoke,
+	.destroy	= keyring_destroy,
+	.describe	= keyring_describe,
+	.read		= keyring_read,
+};
+EXPORT_SYMBOL(key_type_keyring);
+
+/*
+ * Semaphore to serialise link/link calls to prevent two link calls in parallel
+ * introducing a cycle.
+ */
+static DECLARE_RWSEM(keyring_serialise_link_sem);
+
+/*
+ * Publish the name of a keyring so that it can be found by name (if it has
+ * one).
+ */
+static void keyring_publish_name(struct key *keyring)
+{
+	int bucket;
+
+	if (keyring->description) {
+		bucket = keyring_hash(keyring->description);
+
+		write_lock(&keyring_name_lock);
+
+		if (!keyring_name_hash[bucket].next)
+			INIT_LIST_HEAD(&keyring_name_hash[bucket]);
+
+		list_add_tail(&keyring->name_link,
+			      &keyring_name_hash[bucket]);
+
+		write_unlock(&keyring_name_lock);
+	}
+}
+
+/*
+ * Preparse a keyring payload
+ */
+static int keyring_preparse(struct key_preparsed_payload *prep)
+{
+	return prep->datalen != 0 ? -EINVAL : 0;
+}
+
+/*
+ * Free a preparse of a user defined key payload
+ */
+static void keyring_free_preparse(struct key_preparsed_payload *prep)
+{
+}
+
+/*
+ * Initialise a keyring.
+ *
+ * Returns 0 on success, -EINVAL if given any data.
+ */
+static int keyring_instantiate(struct key *keyring,
+			       struct key_preparsed_payload *prep)
+{
+	assoc_array_init(&keyring->keys);
+	/* make the keyring available by name if it has one */
+	keyring_publish_name(keyring);
+	return 0;
+}
+
+/*
+ * Multiply 64-bits by 32-bits to 96-bits and fold back to 64-bit.  Ideally we'd
+ * fold the carry back too, but that requires inline asm.
+ */
+static u64 mult_64x32_and_fold(u64 x, u32 y)
+{
+	u64 hi = (u64)(u32)(x >> 32) * y;
+	u64 lo = (u64)(u32)(x) * y;
+	return lo + ((u64)(u32)hi << 32) + (u32)(hi >> 32);
+}
+
+/*
+ * Hash a key type and description.
+ */
+static unsigned long hash_key_type_and_desc(const struct keyring_index_key *index_key)
+{
+	const unsigned level_shift = ASSOC_ARRAY_LEVEL_STEP;
+	const unsigned long fan_mask = ASSOC_ARRAY_FAN_MASK;
+	const char *description = index_key->description;
+	unsigned long hash, type;
+	u32 piece;
+	u64 acc;
+	int n, desc_len = index_key->desc_len;
+
+	type = (unsigned long)index_key->type;
+
+	acc = mult_64x32_and_fold(type, desc_len + 13);
+	acc = mult_64x32_and_fold(acc, 9207);
+	for (;;) {
+		n = desc_len;
+		if (n <= 0)
+			break;
+		if (n > 4)
+			n = 4;
+		piece = 0;
+		memcpy(&piece, description, n);
+		description += n;
+		desc_len -= n;
+		acc = mult_64x32_and_fold(acc, piece);
+		acc = mult_64x32_and_fold(acc, 9207);
+	}
+
+	/* Fold the hash down to 32 bits if need be. */
+	hash = acc;
+	if (ASSOC_ARRAY_KEY_CHUNK_SIZE == 32)
+		hash ^= acc >> 32;
+
+	/* Squidge all the keyrings into a separate part of the tree to
+	 * ordinary keys by making sure the lowest level segment in the hash is
+	 * zero for keyrings and non-zero otherwise.
+	 */
+	if (index_key->type != &key_type_keyring && (hash & fan_mask) == 0)
+		return hash | (hash >> (ASSOC_ARRAY_KEY_CHUNK_SIZE - level_shift)) | 1;
+	if (index_key->type == &key_type_keyring && (hash & fan_mask) != 0)
+		return (hash + (hash << level_shift)) & ~fan_mask;
+	return hash;
+}
+
+/*
+ * Build the next index key chunk.
+ *
+ * On 32-bit systems the index key is laid out as:
+ *
+ *	0	4	5	9...
+ *	hash	desclen	typeptr	desc[]
+ *
+ * On 64-bit systems:
+ *
+ *	0	8	9	17...
+ *	hash	desclen	typeptr	desc[]
+ *
+ * We return it one word-sized chunk at a time.
+ */
+static unsigned long keyring_get_key_chunk(const void *data, int level)
+{
+	const struct keyring_index_key *index_key = data;
+	unsigned long chunk = 0;
+	long offset = 0;
+	int desc_len = index_key->desc_len, n = sizeof(chunk);
+
+	level /= ASSOC_ARRAY_KEY_CHUNK_SIZE;
+	switch (level) {
+	case 0:
+		return hash_key_type_and_desc(index_key);
+	case 1:
+		return ((unsigned long)index_key->type << 8) | desc_len;
+	case 2:
+		if (desc_len == 0)
+			return (u8)((unsigned long)index_key->type >>
+				    (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8));
+		n--;
+		offset = 1;
+	default:
+		offset += sizeof(chunk) - 1;
+		offset += (level - 3) * sizeof(chunk);
+		if (offset >= desc_len)
+			return 0;
+		desc_len -= offset;
+		if (desc_len > n)
+			desc_len = n;
+		offset += desc_len;
+		do {
+			chunk <<= 8;
+			chunk |= ((u8*)index_key->description)[--offset];
+		} while (--desc_len > 0);
+
+		if (level == 2) {
+			chunk <<= 8;
+			chunk |= (u8)((unsigned long)index_key->type >>
+				      (ASSOC_ARRAY_KEY_CHUNK_SIZE - 8));
+		}
+		return chunk;
+	}
+}
+
+static unsigned long keyring_get_object_key_chunk(const void *object, int level)
+{
+	const struct key *key = keyring_ptr_to_key(object);
+	return keyring_get_key_chunk(&key->index_key, level);
+}
+
+static bool keyring_compare_object(const void *object, const void *data)
+{
+	const struct keyring_index_key *index_key = data;
+	const struct key *key = keyring_ptr_to_key(object);
+
+	return key->index_key.type == index_key->type &&
+		key->index_key.desc_len == index_key->desc_len &&
+		memcmp(key->index_key.description, index_key->description,
+		       index_key->desc_len) == 0;
+}
+
+/*
+ * Compare the index keys of a pair of objects and determine the bit position
+ * at which they differ - if they differ.
+ */
+static int keyring_diff_objects(const void *object, const void *data)
+{
+	const struct key *key_a = keyring_ptr_to_key(object);
+	const struct keyring_index_key *a = &key_a->index_key;
+	const struct keyring_index_key *b = data;
+	unsigned long seg_a, seg_b;
+	int level, i;
+
+	level = 0;
+	seg_a = hash_key_type_and_desc(a);
+	seg_b = hash_key_type_and_desc(b);
+	if ((seg_a ^ seg_b) != 0)
+		goto differ;
+
+	/* The number of bits contributed by the hash is controlled by a
+	 * constant in the assoc_array headers.  Everything else thereafter we
+	 * can deal with as being machine word-size dependent.
+	 */
+	level += ASSOC_ARRAY_KEY_CHUNK_SIZE / 8;
+	seg_a = a->desc_len;
+	seg_b = b->desc_len;
+	if ((seg_a ^ seg_b) != 0)
+		goto differ;
+
+	/* The next bit may not work on big endian */
+	level++;
+	seg_a = (unsigned long)a->type;
+	seg_b = (unsigned long)b->type;
+	if ((seg_a ^ seg_b) != 0)
+		goto differ;
+
+	level += sizeof(unsigned long);
+	if (a->desc_len == 0)
+		goto same;
+
+	i = 0;
+	if (((unsigned long)a->description | (unsigned long)b->description) &
+	    (sizeof(unsigned long) - 1)) {
+		do {
+			seg_a = *(unsigned long *)(a->description + i);
+			seg_b = *(unsigned long *)(b->description + i);
+			if ((seg_a ^ seg_b) != 0)
+				goto differ_plus_i;
+			i += sizeof(unsigned long);
+		} while (i < (a->desc_len & (sizeof(unsigned long) - 1)));
+	}
+
+	for (; i < a->desc_len; i++) {
+		seg_a = *(unsigned char *)(a->description + i);
+		seg_b = *(unsigned char *)(b->description + i);
+		if ((seg_a ^ seg_b) != 0)
+			goto differ_plus_i;
+	}
+
+same:
+	return -1;
+
+differ_plus_i:
+	level += i;
+differ:
+	i = level * 8 + __ffs(seg_a ^ seg_b);
+	return i;
+}
+
+/*
+ * Free an object after stripping the keyring flag off of the pointer.
+ */
+static void keyring_free_object(void *object)
+{
+	key_put(keyring_ptr_to_key(object));
+}
+
+/*
+ * Operations for keyring management by the index-tree routines.
+ */
+static const struct assoc_array_ops keyring_assoc_array_ops = {
+	.get_key_chunk		= keyring_get_key_chunk,
+	.get_object_key_chunk	= keyring_get_object_key_chunk,
+	.compare_object		= keyring_compare_object,
+	.diff_objects		= keyring_diff_objects,
+	.free_object		= keyring_free_object,
+};
+
+/*
+ * Clean up a keyring when it is destroyed.  Unpublish its name if it had one
+ * and dispose of its data.
+ *
+ * The garbage collector detects the final key_put(), removes the keyring from
+ * the serial number tree and then does RCU synchronisation before coming here,
+ * so we shouldn't need to worry about code poking around here with the RCU
+ * readlock held by this time.
+ */
+static void keyring_destroy(struct key *keyring)
+{
+	if (keyring->description) {
+		write_lock(&keyring_name_lock);
+
+		if (keyring->name_link.next != NULL &&
+		    !list_empty(&keyring->name_link))
+			list_del(&keyring->name_link);
+
+		write_unlock(&keyring_name_lock);
+	}
+
+	if (keyring->restrict_link) {
+		struct key_restriction *keyres = keyring->restrict_link;
+
+		key_put(keyres->key);
+		kfree(keyres);
+	}
+
+	assoc_array_destroy(&keyring->keys, &keyring_assoc_array_ops);
+}
+
+/*
+ * Describe a keyring for /proc.
+ */
+static void keyring_describe(const struct key *keyring, struct seq_file *m)
+{
+	if (keyring->description)
+		seq_puts(m, keyring->description);
+	else
+		seq_puts(m, "[anon]");
+
+	if (key_is_positive(keyring)) {
+		if (keyring->keys.nr_leaves_on_tree != 0)
+			seq_printf(m, ": %lu", keyring->keys.nr_leaves_on_tree);
+		else
+			seq_puts(m, ": empty");
+	}
+}
+
+struct keyring_read_iterator_context {
+	size_t			buflen;
+	size_t			count;
+	key_serial_t __user	*buffer;
+};
+
+static int keyring_read_iterator(const void *object, void *data)
+{
+	struct keyring_read_iterator_context *ctx = data;
+	const struct key *key = keyring_ptr_to_key(object);
+
+	kenter("{%s,%d},,{%zu/%zu}",
+	       key->type->name, key->serial, ctx->count, ctx->buflen);
+
+	if (ctx->count >= ctx->buflen)
+		return 1;
+
+	*ctx->buffer++ = key->serial;
+	ctx->count += sizeof(key->serial);
+	return 0;
+}
+
+/*
+ * Read a list of key IDs from the keyring's contents in binary form
+ *
+ * The keyring's semaphore is read-locked by the caller.  This prevents someone
+ * from modifying it under us - which could cause us to read key IDs multiple
+ * times.
+ */
+static long keyring_read(const struct key *keyring,
+			 char __user *buffer, size_t buflen)
+{
+	struct keyring_read_iterator_context ctx;
+	long ret;
+
+	kenter("{%d},,%zu", key_serial(keyring), buflen);
+
+	if (buflen & (sizeof(key_serial_t) - 1))
+		return -EINVAL;
+
+	/* Copy as many key IDs as fit into the buffer */
+	if (buffer && buflen) {
+		ctx.buffer = (key_serial_t __user *)buffer;
+		ctx.buflen = buflen;
+		ctx.count = 0;
+		ret = assoc_array_iterate(&keyring->keys,
+					  keyring_read_iterator, &ctx);
+		if (ret < 0) {
+			kleave(" = %ld [iterate]", ret);
+			return ret;
+		}
+	}
+
+	/* Return the size of the buffer needed */
+	ret = keyring->keys.nr_leaves_on_tree * sizeof(key_serial_t);
+	if (ret <= buflen)
+		kleave("= %ld [ok]", ret);
+	else
+		kleave("= %ld [buffer too small]", ret);
+	return ret;
+}
+
+/*
+ * Allocate a keyring and link into the destination keyring.
+ */
+struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid,
+			  const struct cred *cred, key_perm_t perm,
+			  unsigned long flags,
+			  struct key_restriction *restrict_link,
+			  struct key *dest)
+{
+	struct key *keyring;
+	int ret;
+
+	keyring = key_alloc(&key_type_keyring, description,
+			    uid, gid, cred, perm, flags, restrict_link);
+	if (!IS_ERR(keyring)) {
+		ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL);
+		if (ret < 0) {
+			key_put(keyring);
+			keyring = ERR_PTR(ret);
+		}
+	}
+
+	return keyring;
+}
+EXPORT_SYMBOL(keyring_alloc);
+
+/**
+ * restrict_link_reject - Give -EPERM to restrict link
+ * @keyring: The keyring being added to.
+ * @type: The type of key being added.
+ * @payload: The payload of the key intended to be added.
+ * @data: Additional data for evaluating restriction.
+ *
+ * Reject the addition of any links to a keyring.  It can be overridden by
+ * passing KEY_ALLOC_BYPASS_RESTRICTION to key_instantiate_and_link() when
+ * adding a key to a keyring.
+ *
+ * This is meant to be stored in a key_restriction structure which is passed
+ * in the restrict_link parameter to keyring_alloc().
+ */
+int restrict_link_reject(struct key *keyring,
+			 const struct key_type *type,
+			 const union key_payload *payload,
+			 struct key *restriction_key)
+{
+	return -EPERM;
+}
+
+/*
+ * By default, we keys found by getting an exact match on their descriptions.
+ */
+bool key_default_cmp(const struct key *key,
+		     const struct key_match_data *match_data)
+{
+	return strcmp(key->description, match_data->raw_data) == 0;
+}
+
+/*
+ * Iteration function to consider each key found.
+ */
+static int keyring_search_iterator(const void *object, void *iterator_data)
+{
+	struct keyring_search_context *ctx = iterator_data;
+	const struct key *key = keyring_ptr_to_key(object);
+	unsigned long kflags = READ_ONCE(key->flags);
+	short state = READ_ONCE(key->state);
+
+	kenter("{%d}", key->serial);
+
+	/* ignore keys not of this type */
+	if (key->type != ctx->index_key.type) {
+		kleave(" = 0 [!type]");
+		return 0;
+	}
+
+	/* skip invalidated, revoked and expired keys */
+	if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
+		time64_t expiry = READ_ONCE(key->expiry);
+
+		if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
+			      (1 << KEY_FLAG_REVOKED))) {
+			ctx->result = ERR_PTR(-EKEYREVOKED);
+			kleave(" = %d [invrev]", ctx->skipped_ret);
+			goto skipped;
+		}
+
+		if (expiry && ctx->now >= expiry) {
+			if (!(ctx->flags & KEYRING_SEARCH_SKIP_EXPIRED))
+				ctx->result = ERR_PTR(-EKEYEXPIRED);
+			kleave(" = %d [expire]", ctx->skipped_ret);
+			goto skipped;
+		}
+	}
+
+	/* keys that don't match */
+	if (!ctx->match_data.cmp(key, &ctx->match_data)) {
+		kleave(" = 0 [!match]");
+		return 0;
+	}
+
+	/* key must have search permissions */
+	if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) &&
+	    key_task_permission(make_key_ref(key, ctx->possessed),
+				ctx->cred, KEY_NEED_SEARCH) < 0) {
+		ctx->result = ERR_PTR(-EACCES);
+		kleave(" = %d [!perm]", ctx->skipped_ret);
+		goto skipped;
+	}
+
+	if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
+		/* we set a different error code if we pass a negative key */
+		if (state < 0) {
+			ctx->result = ERR_PTR(state);
+			kleave(" = %d [neg]", ctx->skipped_ret);
+			goto skipped;
+		}
+	}
+
+	/* Found */
+	ctx->result = make_key_ref(key, ctx->possessed);
+	kleave(" = 1 [found]");
+	return 1;
+
+skipped:
+	return ctx->skipped_ret;
+}
+
+/*
+ * Search inside a keyring for a key.  We can search by walking to it
+ * directly based on its index-key or we can iterate over the entire
+ * tree looking for it, based on the match function.
+ */
+static int search_keyring(struct key *keyring, struct keyring_search_context *ctx)
+{
+	if (ctx->match_data.lookup_type == KEYRING_SEARCH_LOOKUP_DIRECT) {
+		const void *object;
+
+		object = assoc_array_find(&keyring->keys,
+					  &keyring_assoc_array_ops,
+					  &ctx->index_key);
+		return object ? ctx->iterator(object, ctx) : 0;
+	}
+	return assoc_array_iterate(&keyring->keys, ctx->iterator, ctx);
+}
+
+/*
+ * Search a tree of keyrings that point to other keyrings up to the maximum
+ * depth.
+ */
+static bool search_nested_keyrings(struct key *keyring,
+				   struct keyring_search_context *ctx)
+{
+	struct {
+		struct key *keyring;
+		struct assoc_array_node *node;
+		int slot;
+	} stack[KEYRING_SEARCH_MAX_DEPTH];
+
+	struct assoc_array_shortcut *shortcut;
+	struct assoc_array_node *node;
+	struct assoc_array_ptr *ptr;
+	struct key *key;
+	int sp = 0, slot;
+
+	kenter("{%d},{%s,%s}",
+	       keyring->serial,
+	       ctx->index_key.type->name,
+	       ctx->index_key.description);
+
+#define STATE_CHECKS (KEYRING_SEARCH_NO_STATE_CHECK | KEYRING_SEARCH_DO_STATE_CHECK)
+	BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
+	       (ctx->flags & STATE_CHECKS) == STATE_CHECKS);
+
+	/* Check to see if this top-level keyring is what we are looking for
+	 * and whether it is valid or not.
+	 */
+	if (ctx->match_data.lookup_type == KEYRING_SEARCH_LOOKUP_ITERATE ||
+	    keyring_compare_object(keyring, &ctx->index_key)) {
+		ctx->skipped_ret = 2;
+		switch (ctx->iterator(keyring_key_to_ptr(keyring), ctx)) {
+		case 1:
+			goto found;
+		case 2:
+			return false;
+		default:
+			break;
+		}
+	}
+
+	ctx->skipped_ret = 0;
+
+	/* Start processing a new keyring */
+descend_to_keyring:
+	kdebug("descend to %d", keyring->serial);
+	if (keyring->flags & ((1 << KEY_FLAG_INVALIDATED) |
+			      (1 << KEY_FLAG_REVOKED)))
+		goto not_this_keyring;
+
+	/* Search through the keys in this keyring before its searching its
+	 * subtrees.
+	 */
+	if (search_keyring(keyring, ctx))
+		goto found;
+
+	/* Then manually iterate through the keyrings nested in this one.
+	 *
+	 * Start from the root node of the index tree.  Because of the way the
+	 * hash function has been set up, keyrings cluster on the leftmost
+	 * branch of the root node (root slot 0) or in the root node itself.
+	 * Non-keyrings avoid the leftmost branch of the root entirely (root
+	 * slots 1-15).
+	 */
+	ptr = READ_ONCE(keyring->keys.root);
+	if (!ptr)
+		goto not_this_keyring;
+
+	if (assoc_array_ptr_is_shortcut(ptr)) {
+		/* If the root is a shortcut, either the keyring only contains
+		 * keyring pointers (everything clusters behind root slot 0) or
+		 * doesn't contain any keyring pointers.
+		 */
+		shortcut = assoc_array_ptr_to_shortcut(ptr);
+		if ((shortcut->index_key[0] & ASSOC_ARRAY_FAN_MASK) != 0)
+			goto not_this_keyring;
+
+		ptr = READ_ONCE(shortcut->next_node);
+		node = assoc_array_ptr_to_node(ptr);
+		goto begin_node;
+	}
+
+	node = assoc_array_ptr_to_node(ptr);
+	ptr = node->slots[0];
+	if (!assoc_array_ptr_is_meta(ptr))
+		goto begin_node;
+
+descend_to_node:
+	/* Descend to a more distal node in this keyring's content tree and go
+	 * through that.
+	 */
+	kdebug("descend");
+	if (assoc_array_ptr_is_shortcut(ptr)) {
+		shortcut = assoc_array_ptr_to_shortcut(ptr);
+		ptr = READ_ONCE(shortcut->next_node);
+		BUG_ON(!assoc_array_ptr_is_node(ptr));
+	}
+	node = assoc_array_ptr_to_node(ptr);
+
+begin_node:
+	kdebug("begin_node");
+	slot = 0;
+ascend_to_node:
+	/* Go through the slots in a node */
+	for (; slot < ASSOC_ARRAY_FAN_OUT; slot++) {
+		ptr = READ_ONCE(node->slots[slot]);
+
+		if (assoc_array_ptr_is_meta(ptr) && node->back_pointer)
+			goto descend_to_node;
+
+		if (!keyring_ptr_is_keyring(ptr))
+			continue;
+
+		key = keyring_ptr_to_key(ptr);
+
+		if (sp >= KEYRING_SEARCH_MAX_DEPTH) {
+			if (ctx->flags & KEYRING_SEARCH_DETECT_TOO_DEEP) {
+				ctx->result = ERR_PTR(-ELOOP);
+				return false;
+			}
+			goto not_this_keyring;
+		}
+
+		/* Search a nested keyring */
+		if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) &&
+		    key_task_permission(make_key_ref(key, ctx->possessed),
+					ctx->cred, KEY_NEED_SEARCH) < 0)
+			continue;
+
+		/* stack the current position */
+		stack[sp].keyring = keyring;
+		stack[sp].node = node;
+		stack[sp].slot = slot;
+		sp++;
+
+		/* begin again with the new keyring */
+		keyring = key;
+		goto descend_to_keyring;
+	}
+
+	/* We've dealt with all the slots in the current node, so now we need
+	 * to ascend to the parent and continue processing there.
+	 */
+	ptr = READ_ONCE(node->back_pointer);
+	slot = node->parent_slot;
+
+	if (ptr && assoc_array_ptr_is_shortcut(ptr)) {
+		shortcut = assoc_array_ptr_to_shortcut(ptr);
+		ptr = READ_ONCE(shortcut->back_pointer);
+		slot = shortcut->parent_slot;
+	}
+	if (!ptr)
+		goto not_this_keyring;
+	node = assoc_array_ptr_to_node(ptr);
+	slot++;
+
+	/* If we've ascended to the root (zero backpointer), we must have just
+	 * finished processing the leftmost branch rather than the root slots -
+	 * so there can't be any more keyrings for us to find.
+	 */
+	if (node->back_pointer) {
+		kdebug("ascend %d", slot);
+		goto ascend_to_node;
+	}
+
+	/* The keyring we're looking at was disqualified or didn't contain a
+	 * matching key.
+	 */
+not_this_keyring:
+	kdebug("not_this_keyring %d", sp);
+	if (sp <= 0) {
+		kleave(" = false");
+		return false;
+	}
+
+	/* Resume the processing of a keyring higher up in the tree */
+	sp--;
+	keyring = stack[sp].keyring;
+	node = stack[sp].node;
+	slot = stack[sp].slot + 1;
+	kdebug("ascend to %d [%d]", keyring->serial, slot);
+	goto ascend_to_node;
+
+	/* We found a viable match */
+found:
+	key = key_ref_to_ptr(ctx->result);
+	key_check(key);
+	if (!(ctx->flags & KEYRING_SEARCH_NO_UPDATE_TIME)) {
+		key->last_used_at = ctx->now;
+		keyring->last_used_at = ctx->now;
+		while (sp > 0)
+			stack[--sp].keyring->last_used_at = ctx->now;
+	}
+	kleave(" = true");
+	return true;
+}
+
+/**
+ * keyring_search_aux - Search a keyring tree for a key matching some criteria
+ * @keyring_ref: A pointer to the keyring with possession indicator.
+ * @ctx: The keyring search context.
+ *
+ * Search the supplied keyring tree for a key that matches the criteria given.
+ * The root keyring and any linked keyrings must grant Search permission to the
+ * caller to be searchable and keys can only be found if they too grant Search
+ * to the caller. The possession flag on the root keyring pointer controls use
+ * of the possessor bits in permissions checking of the entire tree.  In
+ * addition, the LSM gets to forbid keyring searches and key matches.
+ *
+ * The search is performed as a breadth-then-depth search up to the prescribed
+ * limit (KEYRING_SEARCH_MAX_DEPTH).
+ *
+ * Keys are matched to the type provided and are then filtered by the match
+ * function, which is given the description to use in any way it sees fit.  The
+ * match function may use any attributes of a key that it wishes to to
+ * determine the match.  Normally the match function from the key type would be
+ * used.
+ *
+ * RCU can be used to prevent the keyring key lists from disappearing without
+ * the need to take lots of locks.
+ *
+ * Returns a pointer to the found key and increments the key usage count if
+ * successful; -EAGAIN if no matching keys were found, or if expired or revoked
+ * keys were found; -ENOKEY if only negative keys were found; -ENOTDIR if the
+ * specified keyring wasn't a keyring.
+ *
+ * In the case of a successful return, the possession attribute from
+ * @keyring_ref is propagated to the returned key reference.
+ */
+key_ref_t keyring_search_aux(key_ref_t keyring_ref,
+			     struct keyring_search_context *ctx)
+{
+	struct key *keyring;
+	long err;
+
+	ctx->iterator = keyring_search_iterator;
+	ctx->possessed = is_key_possessed(keyring_ref);
+	ctx->result = ERR_PTR(-EAGAIN);
+
+	keyring = key_ref_to_ptr(keyring_ref);
+	key_check(keyring);
+
+	if (keyring->type != &key_type_keyring)
+		return ERR_PTR(-ENOTDIR);
+
+	if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM)) {
+		err = key_task_permission(keyring_ref, ctx->cred, KEY_NEED_SEARCH);
+		if (err < 0)
+			return ERR_PTR(err);
+	}
+
+	rcu_read_lock();
+	ctx->now = ktime_get_real_seconds();
+	if (search_nested_keyrings(keyring, ctx))
+		__key_get(key_ref_to_ptr(ctx->result));
+	rcu_read_unlock();
+	return ctx->result;
+}
+
+/**
+ * keyring_search - Search the supplied keyring tree for a matching key
+ * @keyring: The root of the keyring tree to be searched.
+ * @type: The type of keyring we want to find.
+ * @description: The name of the keyring we want to find.
+ *
+ * As keyring_search_aux() above, but using the current task's credentials and
+ * type's default matching function and preferred search method.
+ */
+key_ref_t keyring_search(key_ref_t keyring,
+			 struct key_type *type,
+			 const char *description)
+{
+	struct keyring_search_context ctx = {
+		.index_key.type		= type,
+		.index_key.description	= description,
+		.index_key.desc_len	= strlen(description),
+		.cred			= current_cred(),
+		.match_data.cmp		= key_default_cmp,
+		.match_data.raw_data	= description,
+		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
+		.flags			= KEYRING_SEARCH_DO_STATE_CHECK,
+	};
+	key_ref_t key;
+	int ret;
+
+	if (type->match_preparse) {
+		ret = type->match_preparse(&ctx.match_data);
+		if (ret < 0)
+			return ERR_PTR(ret);
+	}
+
+	key = keyring_search_aux(keyring, &ctx);
+
+	if (type->match_free)
+		type->match_free(&ctx.match_data);
+	return key;
+}
+EXPORT_SYMBOL(keyring_search);
+
+static struct key_restriction *keyring_restriction_alloc(
+	key_restrict_link_func_t check)
+{
+	struct key_restriction *keyres =
+		kzalloc(sizeof(struct key_restriction), GFP_KERNEL);
+
+	if (!keyres)
+		return ERR_PTR(-ENOMEM);
+
+	keyres->check = check;
+
+	return keyres;
+}
+
+/*
+ * Semaphore to serialise restriction setup to prevent reference count
+ * cycles through restriction key pointers.
+ */
+static DECLARE_RWSEM(keyring_serialise_restrict_sem);
+
+/*
+ * Check for restriction cycles that would prevent keyring garbage collection.
+ * keyring_serialise_restrict_sem must be held.
+ */
+static bool keyring_detect_restriction_cycle(const struct key *dest_keyring,
+					     struct key_restriction *keyres)
+{
+	while (keyres && keyres->key &&
+	       keyres->key->type == &key_type_keyring) {
+		if (keyres->key == dest_keyring)
+			return true;
+
+		keyres = keyres->key->restrict_link;
+	}
+
+	return false;
+}
+
+/**
+ * keyring_restrict - Look up and apply a restriction to a keyring
+ *
+ * @keyring: The keyring to be restricted
+ * @restriction: The restriction options to apply to the keyring
+ */
+int keyring_restrict(key_ref_t keyring_ref, const char *type,
+		     const char *restriction)
+{
+	struct key *keyring;
+	struct key_type *restrict_type = NULL;
+	struct key_restriction *restrict_link;
+	int ret = 0;
+
+	keyring = key_ref_to_ptr(keyring_ref);
+	key_check(keyring);
+
+	if (keyring->type != &key_type_keyring)
+		return -ENOTDIR;
+
+	if (!type) {
+		restrict_link = keyring_restriction_alloc(restrict_link_reject);
+	} else {
+		restrict_type = key_type_lookup(type);
+
+		if (IS_ERR(restrict_type))
+			return PTR_ERR(restrict_type);
+
+		if (!restrict_type->lookup_restriction) {
+			ret = -ENOENT;
+			goto error;
+		}
+
+		restrict_link = restrict_type->lookup_restriction(restriction);
+	}
+
+	if (IS_ERR(restrict_link)) {
+		ret = PTR_ERR(restrict_link);
+		goto error;
+	}
+
+	down_write(&keyring->sem);
+	down_write(&keyring_serialise_restrict_sem);
+
+	if (keyring->restrict_link)
+		ret = -EEXIST;
+	else if (keyring_detect_restriction_cycle(keyring, restrict_link))
+		ret = -EDEADLK;
+	else
+		keyring->restrict_link = restrict_link;
+
+	up_write(&keyring_serialise_restrict_sem);
+	up_write(&keyring->sem);
+
+	if (ret < 0) {
+		key_put(restrict_link->key);
+		kfree(restrict_link);
+	}
+
+error:
+	if (restrict_type)
+		key_type_put(restrict_type);
+
+	return ret;
+}
+EXPORT_SYMBOL(keyring_restrict);
+
+/*
+ * Search the given keyring for a key that might be updated.
+ *
+ * The caller must guarantee that the keyring is a keyring and that the
+ * permission is granted to modify the keyring as no check is made here.  The
+ * caller must also hold a lock on the keyring semaphore.
+ *
+ * Returns a pointer to the found key with usage count incremented if
+ * successful and returns NULL if not found.  Revoked and invalidated keys are
+ * skipped over.
+ *
+ * If successful, the possession indicator is propagated from the keyring ref
+ * to the returned key reference.
+ */
+key_ref_t find_key_to_update(key_ref_t keyring_ref,
+			     const struct keyring_index_key *index_key)
+{
+	struct key *keyring, *key;
+	const void *object;
+
+	keyring = key_ref_to_ptr(keyring_ref);
+
+	kenter("{%d},{%s,%s}",
+	       keyring->serial, index_key->type->name, index_key->description);
+
+	object = assoc_array_find(&keyring->keys, &keyring_assoc_array_ops,
+				  index_key);
+
+	if (object)
+		goto found;
+
+	kleave(" = NULL");
+	return NULL;
+
+found:
+	key = keyring_ptr_to_key(object);
+	if (key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+			  (1 << KEY_FLAG_REVOKED))) {
+		kleave(" = NULL [x]");
+		return NULL;
+	}
+	__key_get(key);
+	kleave(" = {%d}", key->serial);
+	return make_key_ref(key, is_key_possessed(keyring_ref));
+}
+
+/*
+ * Find a keyring with the specified name.
+ *
+ * Only keyrings that have nonzero refcount, are not revoked, and are owned by a
+ * user in the current user namespace are considered.  If @uid_keyring is %true,
+ * the keyring additionally must have been allocated as a user or user session
+ * keyring; otherwise, it must grant Search permission directly to the caller.
+ *
+ * Returns a pointer to the keyring with the keyring's refcount having being
+ * incremented on success.  -ENOKEY is returned if a key could not be found.
+ */
+struct key *find_keyring_by_name(const char *name, bool uid_keyring)
+{
+	struct key *keyring;
+	int bucket;
+
+	if (!name)
+		return ERR_PTR(-EINVAL);
+
+	bucket = keyring_hash(name);
+
+	read_lock(&keyring_name_lock);
+
+	if (keyring_name_hash[bucket].next) {
+		/* search this hash bucket for a keyring with a matching name
+		 * that's readable and that hasn't been revoked */
+		list_for_each_entry(keyring,
+				    &keyring_name_hash[bucket],
+				    name_link
+				    ) {
+			if (!kuid_has_mapping(current_user_ns(), keyring->user->uid))
+				continue;
+
+			if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+				continue;
+
+			if (strcmp(keyring->description, name) != 0)
+				continue;
+
+			if (uid_keyring) {
+				if (!test_bit(KEY_FLAG_UID_KEYRING,
+					      &keyring->flags))
+					continue;
+			} else {
+				if (key_permission(make_key_ref(keyring, 0),
+						   KEY_NEED_SEARCH) < 0)
+					continue;
+			}
+
+			/* we've got a match but we might end up racing with
+			 * key_cleanup() if the keyring is currently 'dead'
+			 * (ie. it has a zero usage count) */
+			if (!refcount_inc_not_zero(&keyring->usage))
+				continue;
+			keyring->last_used_at = ktime_get_real_seconds();
+			goto out;
+		}
+	}
+
+	keyring = ERR_PTR(-ENOKEY);
+out:
+	read_unlock(&keyring_name_lock);
+	return keyring;
+}
+
+static int keyring_detect_cycle_iterator(const void *object,
+					 void *iterator_data)
+{
+	struct keyring_search_context *ctx = iterator_data;
+	const struct key *key = keyring_ptr_to_key(object);
+
+	kenter("{%d}", key->serial);
+
+	/* We might get a keyring with matching index-key that is nonetheless a
+	 * different keyring. */
+	if (key != ctx->match_data.raw_data)
+		return 0;
+
+	ctx->result = ERR_PTR(-EDEADLK);
+	return 1;
+}
+
+/*
+ * See if a cycle will will be created by inserting acyclic tree B in acyclic
+ * tree A at the topmost level (ie: as a direct child of A).
+ *
+ * Since we are adding B to A at the top level, checking for cycles should just
+ * be a matter of seeing if node A is somewhere in tree B.
+ */
+static int keyring_detect_cycle(struct key *A, struct key *B)
+{
+	struct keyring_search_context ctx = {
+		.index_key		= A->index_key,
+		.match_data.raw_data	= A,
+		.match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT,
+		.iterator		= keyring_detect_cycle_iterator,
+		.flags			= (KEYRING_SEARCH_NO_STATE_CHECK |
+					   KEYRING_SEARCH_NO_UPDATE_TIME |
+					   KEYRING_SEARCH_NO_CHECK_PERM |
+					   KEYRING_SEARCH_DETECT_TOO_DEEP),
+	};
+
+	rcu_read_lock();
+	search_nested_keyrings(B, &ctx);
+	rcu_read_unlock();
+	return PTR_ERR(ctx.result) == -EAGAIN ? 0 : PTR_ERR(ctx.result);
+}
+
+/*
+ * Preallocate memory so that a key can be linked into to a keyring.
+ */
+int __key_link_begin(struct key *keyring,
+		     const struct keyring_index_key *index_key,
+		     struct assoc_array_edit **_edit)
+	__acquires(&keyring->sem)
+	__acquires(&keyring_serialise_link_sem)
+{
+	struct assoc_array_edit *edit;
+	int ret;
+
+	kenter("%d,%s,%s,",
+	       keyring->serial, index_key->type->name, index_key->description);
+
+	BUG_ON(index_key->desc_len == 0);
+
+	if (keyring->type != &key_type_keyring)
+		return -ENOTDIR;
+
+	down_write(&keyring->sem);
+
+	ret = -EKEYREVOKED;
+	if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+		goto error_krsem;
+
+	/* serialise link/link calls to prevent parallel calls causing a cycle
+	 * when linking two keyring in opposite orders */
+	if (index_key->type == &key_type_keyring)
+		down_write(&keyring_serialise_link_sem);
+
+	/* Create an edit script that will insert/replace the key in the
+	 * keyring tree.
+	 */
+	edit = assoc_array_insert(&keyring->keys,
+				  &keyring_assoc_array_ops,
+				  index_key,
+				  NULL);
+	if (IS_ERR(edit)) {
+		ret = PTR_ERR(edit);
+		goto error_sem;
+	}
+
+	/* If we're not replacing a link in-place then we're going to need some
+	 * extra quota.
+	 */
+	if (!edit->dead_leaf) {
+		ret = key_payload_reserve(keyring,
+					  keyring->datalen + KEYQUOTA_LINK_BYTES);
+		if (ret < 0)
+			goto error_cancel;
+	}
+
+	*_edit = edit;
+	kleave(" = 0");
+	return 0;
+
+error_cancel:
+	assoc_array_cancel_edit(edit);
+error_sem:
+	if (index_key->type == &key_type_keyring)
+		up_write(&keyring_serialise_link_sem);
+error_krsem:
+	up_write(&keyring->sem);
+	kleave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Check already instantiated keys aren't going to be a problem.
+ *
+ * The caller must have called __key_link_begin(). Don't need to call this for
+ * keys that were created since __key_link_begin() was called.
+ */
+int __key_link_check_live_key(struct key *keyring, struct key *key)
+{
+	if (key->type == &key_type_keyring)
+		/* check that we aren't going to create a cycle by linking one
+		 * keyring to another */
+		return keyring_detect_cycle(keyring, key);
+	return 0;
+}
+
+/*
+ * Link a key into to a keyring.
+ *
+ * Must be called with __key_link_begin() having being called.  Discards any
+ * already extant link to matching key if there is one, so that each keyring
+ * holds at most one link to any given key of a particular type+description
+ * combination.
+ */
+void __key_link(struct key *key, struct assoc_array_edit **_edit)
+{
+	__key_get(key);
+	assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key));
+	assoc_array_apply_edit(*_edit);
+	*_edit = NULL;
+}
+
+/*
+ * Finish linking a key into to a keyring.
+ *
+ * Must be called with __key_link_begin() having being called.
+ */
+void __key_link_end(struct key *keyring,
+		    const struct keyring_index_key *index_key,
+		    struct assoc_array_edit *edit)
+	__releases(&keyring->sem)
+	__releases(&keyring_serialise_link_sem)
+{
+	BUG_ON(index_key->type == NULL);
+	kenter("%d,%s,", keyring->serial, index_key->type->name);
+
+	if (index_key->type == &key_type_keyring)
+		up_write(&keyring_serialise_link_sem);
+
+	if (edit) {
+		if (!edit->dead_leaf) {
+			key_payload_reserve(keyring,
+				keyring->datalen - KEYQUOTA_LINK_BYTES);
+		}
+		assoc_array_cancel_edit(edit);
+	}
+	up_write(&keyring->sem);
+}
+
+/*
+ * Check addition of keys to restricted keyrings.
+ */
+static int __key_link_check_restriction(struct key *keyring, struct key *key)
+{
+	if (!keyring->restrict_link || !keyring->restrict_link->check)
+		return 0;
+	return keyring->restrict_link->check(keyring, key->type, &key->payload,
+					     keyring->restrict_link->key);
+}
+
+/**
+ * key_link - Link a key to a keyring
+ * @keyring: The keyring to make the link in.
+ * @key: The key to link to.
+ *
+ * Make a link in a keyring to a key, such that the keyring holds a reference
+ * on that key and the key can potentially be found by searching that keyring.
+ *
+ * This function will write-lock the keyring's semaphore and will consume some
+ * of the user's key data quota to hold the link.
+ *
+ * Returns 0 if successful, -ENOTDIR if the keyring isn't a keyring,
+ * -EKEYREVOKED if the keyring has been revoked, -ENFILE if the keyring is
+ * full, -EDQUOT if there is insufficient key data quota remaining to add
+ * another link or -ENOMEM if there's insufficient memory.
+ *
+ * It is assumed that the caller has checked that it is permitted for a link to
+ * be made (the keyring should have Write permission and the key Link
+ * permission).
+ */
+int key_link(struct key *keyring, struct key *key)
+{
+	struct assoc_array_edit *edit;
+	int ret;
+
+	kenter("{%d,%d}", keyring->serial, refcount_read(&keyring->usage));
+
+	key_check(keyring);
+	key_check(key);
+
+	ret = __key_link_begin(keyring, &key->index_key, &edit);
+	if (ret == 0) {
+		kdebug("begun {%d,%d}", keyring->serial, refcount_read(&keyring->usage));
+		ret = __key_link_check_restriction(keyring, key);
+		if (ret == 0)
+			ret = __key_link_check_live_key(keyring, key);
+		if (ret == 0)
+			__key_link(key, &edit);
+		__key_link_end(keyring, &key->index_key, edit);
+	}
+
+	kleave(" = %d {%d,%d}", ret, keyring->serial, refcount_read(&keyring->usage));
+	return ret;
+}
+EXPORT_SYMBOL(key_link);
+
+/**
+ * key_unlink - Unlink the first link to a key from a keyring.
+ * @keyring: The keyring to remove the link from.
+ * @key: The key the link is to.
+ *
+ * Remove a link from a keyring to a key.
+ *
+ * This function will write-lock the keyring's semaphore.
+ *
+ * Returns 0 if successful, -ENOTDIR if the keyring isn't a keyring, -ENOENT if
+ * the key isn't linked to by the keyring or -ENOMEM if there's insufficient
+ * memory.
+ *
+ * It is assumed that the caller has checked that it is permitted for a link to
+ * be removed (the keyring should have Write permission; no permissions are
+ * required on the key).
+ */
+int key_unlink(struct key *keyring, struct key *key)
+{
+	struct assoc_array_edit *edit;
+	int ret;
+
+	key_check(keyring);
+	key_check(key);
+
+	if (keyring->type != &key_type_keyring)
+		return -ENOTDIR;
+
+	down_write(&keyring->sem);
+
+	edit = assoc_array_delete(&keyring->keys, &keyring_assoc_array_ops,
+				  &key->index_key);
+	if (IS_ERR(edit)) {
+		ret = PTR_ERR(edit);
+		goto error;
+	}
+	ret = -ENOENT;
+	if (edit == NULL)
+		goto error;
+
+	assoc_array_apply_edit(edit);
+	key_payload_reserve(keyring, keyring->datalen - KEYQUOTA_LINK_BYTES);
+	ret = 0;
+
+error:
+	up_write(&keyring->sem);
+	return ret;
+}
+EXPORT_SYMBOL(key_unlink);
+
+/**
+ * keyring_clear - Clear a keyring
+ * @keyring: The keyring to clear.
+ *
+ * Clear the contents of the specified keyring.
+ *
+ * Returns 0 if successful or -ENOTDIR if the keyring isn't a keyring.
+ */
+int keyring_clear(struct key *keyring)
+{
+	struct assoc_array_edit *edit;
+	int ret;
+
+	if (keyring->type != &key_type_keyring)
+		return -ENOTDIR;
+
+	down_write(&keyring->sem);
+
+	edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops);
+	if (IS_ERR(edit)) {
+		ret = PTR_ERR(edit);
+	} else {
+		if (edit)
+			assoc_array_apply_edit(edit);
+		key_payload_reserve(keyring, 0);
+		ret = 0;
+	}
+
+	up_write(&keyring->sem);
+	return ret;
+}
+EXPORT_SYMBOL(keyring_clear);
+
+/*
+ * Dispose of the links from a revoked keyring.
+ *
+ * This is called with the key sem write-locked.
+ */
+static void keyring_revoke(struct key *keyring)
+{
+	struct assoc_array_edit *edit;
+
+	edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops);
+	if (!IS_ERR(edit)) {
+		if (edit)
+			assoc_array_apply_edit(edit);
+		key_payload_reserve(keyring, 0);
+	}
+}
+
+static bool keyring_gc_select_iterator(void *object, void *iterator_data)
+{
+	struct key *key = keyring_ptr_to_key(object);
+	time64_t *limit = iterator_data;
+
+	if (key_is_dead(key, *limit))
+		return false;
+	key_get(key);
+	return true;
+}
+
+static int keyring_gc_check_iterator(const void *object, void *iterator_data)
+{
+	const struct key *key = keyring_ptr_to_key(object);
+	time64_t *limit = iterator_data;
+
+	key_check(key);
+	return key_is_dead(key, *limit);
+}
+
+/*
+ * Garbage collect pointers from a keyring.
+ *
+ * Not called with any locks held.  The keyring's key struct will not be
+ * deallocated under us as only our caller may deallocate it.
+ */
+void keyring_gc(struct key *keyring, time64_t limit)
+{
+	int result;
+
+	kenter("%x{%s}", keyring->serial, keyring->description ?: "");
+
+	if (keyring->flags & ((1 << KEY_FLAG_INVALIDATED) |
+			      (1 << KEY_FLAG_REVOKED)))
+		goto dont_gc;
+
+	/* scan the keyring looking for dead keys */
+	rcu_read_lock();
+	result = assoc_array_iterate(&keyring->keys,
+				     keyring_gc_check_iterator, &limit);
+	rcu_read_unlock();
+	if (result == true)
+		goto do_gc;
+
+dont_gc:
+	kleave(" [no gc]");
+	return;
+
+do_gc:
+	down_write(&keyring->sem);
+	assoc_array_gc(&keyring->keys, &keyring_assoc_array_ops,
+		       keyring_gc_select_iterator, &limit);
+	up_write(&keyring->sem);
+	kleave(" [gc]");
+}
+
+/*
+ * Garbage collect restriction pointers from a keyring.
+ *
+ * Keyring restrictions are associated with a key type, and must be cleaned
+ * up if the key type is unregistered. The restriction is altered to always
+ * reject additional keys so a keyring cannot be opened up by unregistering
+ * a key type.
+ *
+ * Not called with any keyring locks held. The keyring's key struct will not
+ * be deallocated under us as only our caller may deallocate it.
+ *
+ * The caller is required to hold key_types_sem and dead_type->sem. This is
+ * fulfilled by key_gc_keytype() holding the locks on behalf of
+ * key_garbage_collector(), which it invokes on a workqueue.
+ */
+void keyring_restriction_gc(struct key *keyring, struct key_type *dead_type)
+{
+	struct key_restriction *keyres;
+
+	kenter("%x{%s}", keyring->serial, keyring->description ?: "");
+
+	/*
+	 * keyring->restrict_link is only assigned at key allocation time
+	 * or with the key type locked, so the only values that could be
+	 * concurrently assigned to keyring->restrict_link are for key
+	 * types other than dead_type. Given this, it's ok to check
+	 * the key type before acquiring keyring->sem.
+	 */
+	if (!dead_type || !keyring->restrict_link ||
+	    keyring->restrict_link->keytype != dead_type) {
+		kleave(" [no restriction gc]");
+		return;
+	}
+
+	/* Lock the keyring to ensure that a link is not in progress */
+	down_write(&keyring->sem);
+
+	keyres = keyring->restrict_link;
+
+	keyres->check = restrict_link_reject;
+
+	key_put(keyres->key);
+	keyres->key = NULL;
+	keyres->keytype = NULL;
+
+	up_write(&keyring->sem);
+
+	kleave(" [restriction gc]");
+}
diff --git a/security/keys/permission.c b/security/keys/permission.c
new file mode 100644
index 000000000..f68dc04d6
--- /dev/null
+++ b/security/keys/permission.c
@@ -0,0 +1,110 @@
+/* Key permission checking
+ *
+ * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/security.h>
+#include "internal.h"
+
+/**
+ * key_task_permission - Check a key can be used
+ * @key_ref: The key to check.
+ * @cred: The credentials to use.
+ * @perm: The permissions to check for.
+ *
+ * Check to see whether permission is granted to use a key in the desired way,
+ * but permit the security modules to override.
+ *
+ * The caller must hold either a ref on cred or must hold the RCU readlock.
+ *
+ * Returns 0 if successful, -EACCES if access is denied based on the
+ * permissions bits or the LSM check.
+ */
+int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
+			unsigned perm)
+{
+	struct key *key;
+	key_perm_t kperm;
+	int ret;
+
+	key = key_ref_to_ptr(key_ref);
+
+	/* use the second 8-bits of permissions for keys the caller owns */
+	if (uid_eq(key->uid, cred->fsuid)) {
+		kperm = key->perm >> 16;
+		goto use_these_perms;
+	}
+
+	/* use the third 8-bits of permissions for keys the caller has a group
+	 * membership in common with */
+	if (gid_valid(key->gid) && key->perm & KEY_GRP_ALL) {
+		if (gid_eq(key->gid, cred->fsgid)) {
+			kperm = key->perm >> 8;
+			goto use_these_perms;
+		}
+
+		ret = groups_search(cred->group_info, key->gid);
+		if (ret) {
+			kperm = key->perm >> 8;
+			goto use_these_perms;
+		}
+	}
+
+	/* otherwise use the least-significant 8-bits */
+	kperm = key->perm;
+
+use_these_perms:
+
+	/* use the top 8-bits of permissions for keys the caller possesses
+	 * - possessor permissions are additive with other permissions
+	 */
+	if (is_key_possessed(key_ref))
+		kperm |= key->perm >> 24;
+
+	kperm = kperm & perm & KEY_NEED_ALL;
+
+	if (kperm != perm)
+		return -EACCES;
+
+	/* let LSM be the final arbiter */
+	return security_key_permission(key_ref, cred, perm);
+}
+EXPORT_SYMBOL(key_task_permission);
+
+/**
+ * key_validate - Validate a key.
+ * @key: The key to be validated.
+ *
+ * Check that a key is valid, returning 0 if the key is okay, -ENOKEY if the
+ * key is invalidated, -EKEYREVOKED if the key's type has been removed or if
+ * the key has been revoked or -EKEYEXPIRED if the key has expired.
+ */
+int key_validate(const struct key *key)
+{
+	unsigned long flags = READ_ONCE(key->flags);
+	time64_t expiry = READ_ONCE(key->expiry);
+
+	if (flags & (1 << KEY_FLAG_INVALIDATED))
+		return -ENOKEY;
+
+	/* check it's still accessible */
+	if (flags & ((1 << KEY_FLAG_REVOKED) |
+		     (1 << KEY_FLAG_DEAD)))
+		return -EKEYREVOKED;
+
+	/* check it hasn't expired */
+	if (expiry) {
+		if (ktime_get_real_seconds() >= expiry)
+			return -EKEYEXPIRED;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(key_validate);
diff --git a/security/keys/persistent.c b/security/keys/persistent.c
new file mode 100644
index 000000000..d0cb5b32e
--- /dev/null
+++ b/security/keys/persistent.c
@@ -0,0 +1,169 @@
+/* General persistent per-UID keyrings register
+ *
+ * Copyright (C) 2013 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/user_namespace.h>
+#include <linux/cred.h>
+
+#include "internal.h"
+
+unsigned persistent_keyring_expiry = 3 * 24 * 3600; /* Expire after 3 days of non-use */
+
+/*
+ * Create the persistent keyring register for the current user namespace.
+ *
+ * Called with the namespace's sem locked for writing.
+ */
+static int key_create_persistent_register(struct user_namespace *ns)
+{
+	struct key *reg = keyring_alloc(".persistent_register",
+					KUIDT_INIT(0), KGIDT_INIT(0),
+					current_cred(),
+					((KEY_POS_ALL & ~KEY_POS_SETATTR) |
+					 KEY_USR_VIEW | KEY_USR_READ),
+					KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	ns->persistent_keyring_register = reg;
+	return 0;
+}
+
+/*
+ * Create the persistent keyring for the specified user.
+ *
+ * Called with the namespace's sem locked for writing.
+ */
+static key_ref_t key_create_persistent(struct user_namespace *ns, kuid_t uid,
+				       struct keyring_index_key *index_key)
+{
+	struct key *persistent;
+	key_ref_t reg_ref, persistent_ref;
+
+	if (!ns->persistent_keyring_register) {
+		long err = key_create_persistent_register(ns);
+		if (err < 0)
+			return ERR_PTR(err);
+	} else {
+		reg_ref = make_key_ref(ns->persistent_keyring_register, true);
+		persistent_ref = find_key_to_update(reg_ref, index_key);
+		if (persistent_ref)
+			return persistent_ref;
+	}
+
+	persistent = keyring_alloc(index_key->description,
+				   uid, INVALID_GID, current_cred(),
+				   ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				    KEY_USR_VIEW | KEY_USR_READ),
+				   KEY_ALLOC_NOT_IN_QUOTA, NULL,
+				   ns->persistent_keyring_register);
+	if (IS_ERR(persistent))
+		return ERR_CAST(persistent);
+
+	return make_key_ref(persistent, true);
+}
+
+/*
+ * Get the persistent keyring for a specific UID and link it to the nominated
+ * keyring.
+ */
+static long key_get_persistent(struct user_namespace *ns, kuid_t uid,
+			       key_ref_t dest_ref)
+{
+	struct keyring_index_key index_key;
+	struct key *persistent;
+	key_ref_t reg_ref, persistent_ref;
+	char buf[32];
+	long ret;
+
+	/* Look in the register if it exists */
+	index_key.type = &key_type_keyring;
+	index_key.description = buf;
+	index_key.desc_len = sprintf(buf, "_persistent.%u", from_kuid(ns, uid));
+
+	if (ns->persistent_keyring_register) {
+		reg_ref = make_key_ref(ns->persistent_keyring_register, true);
+		down_read(&ns->persistent_keyring_register_sem);
+		persistent_ref = find_key_to_update(reg_ref, &index_key);
+		up_read(&ns->persistent_keyring_register_sem);
+
+		if (persistent_ref)
+			goto found;
+	}
+
+	/* It wasn't in the register, so we'll need to create it.  We might
+	 * also need to create the register.
+	 */
+	down_write(&ns->persistent_keyring_register_sem);
+	persistent_ref = key_create_persistent(ns, uid, &index_key);
+	up_write(&ns->persistent_keyring_register_sem);
+	if (!IS_ERR(persistent_ref))
+		goto found;
+
+	return PTR_ERR(persistent_ref);
+
+found:
+	ret = key_task_permission(persistent_ref, current_cred(), KEY_NEED_LINK);
+	if (ret == 0) {
+		persistent = key_ref_to_ptr(persistent_ref);
+		ret = key_link(key_ref_to_ptr(dest_ref), persistent);
+		if (ret == 0) {
+			key_set_timeout(persistent, persistent_keyring_expiry);
+			ret = persistent->serial;
+		}
+	}
+
+	key_ref_put(persistent_ref);
+	return ret;
+}
+
+/*
+ * Get the persistent keyring for a specific UID and link it to the nominated
+ * keyring.
+ */
+long keyctl_get_persistent(uid_t _uid, key_serial_t destid)
+{
+	struct user_namespace *ns = current_user_ns();
+	key_ref_t dest_ref;
+	kuid_t uid;
+	long ret;
+
+	/* -1 indicates the current user */
+	if (_uid == (uid_t)-1) {
+		uid = current_uid();
+	} else {
+		uid = make_kuid(ns, _uid);
+		if (!uid_valid(uid))
+			return -EINVAL;
+
+		/* You can only see your own persistent cache if you're not
+		 * sufficiently privileged.
+		 */
+		if (!uid_eq(uid, current_uid()) &&
+		    !uid_eq(uid, current_euid()) &&
+		    !ns_capable(ns, CAP_SETUID))
+			return -EPERM;
+	}
+
+	/* There must be a destination keyring */
+	dest_ref = lookup_user_key(destid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
+	if (IS_ERR(dest_ref))
+		return PTR_ERR(dest_ref);
+	if (key_ref_to_ptr(dest_ref)->type != &key_type_keyring) {
+		ret = -ENOTDIR;
+		goto out_put_dest;
+	}
+
+	ret = key_get_persistent(ns, uid, dest_ref);
+
+out_put_dest:
+	key_ref_put(dest_ref);
+	return ret;
+}
diff --git a/security/keys/proc.c b/security/keys/proc.c
new file mode 100644
index 000000000..7ec2779cb
--- /dev/null
+++ b/security/keys/proc.c
@@ -0,0 +1,325 @@
+/* procfs files for key database enumeration
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <asm/errno.h>
+#include "internal.h"
+
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_keys_stop(struct seq_file *p, void *v);
+static int proc_keys_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_keys_ops = {
+	.start	= proc_keys_start,
+	.next	= proc_keys_next,
+	.stop	= proc_keys_stop,
+	.show	= proc_keys_show,
+};
+
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_key_users_stop(struct seq_file *p, void *v);
+static int proc_key_users_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_key_users_ops = {
+	.start	= proc_key_users_start,
+	.next	= proc_key_users_next,
+	.stop	= proc_key_users_stop,
+	.show	= proc_key_users_show,
+};
+
+/*
+ * Declare the /proc files.
+ */
+static int __init key_proc_init(void)
+{
+	struct proc_dir_entry *p;
+
+	p = proc_create_seq("keys", 0, NULL, &proc_keys_ops);
+	if (!p)
+		panic("Cannot create /proc/keys\n");
+
+	p = proc_create_seq("key-users", 0, NULL, &proc_key_users_ops);
+	if (!p)
+		panic("Cannot create /proc/key-users\n");
+
+	return 0;
+}
+
+__initcall(key_proc_init);
+
+/*
+ * Implement "/proc/keys" to provide a list of the keys on the system that
+ * grant View permission to the caller.
+ */
+static struct rb_node *key_serial_next(struct seq_file *p, struct rb_node *n)
+{
+	struct user_namespace *user_ns = seq_user_ns(p);
+
+	n = rb_next(n);
+	while (n) {
+		struct key *key = rb_entry(n, struct key, serial_node);
+		if (kuid_has_mapping(user_ns, key->user->uid))
+			break;
+		n = rb_next(n);
+	}
+	return n;
+}
+
+static struct key *find_ge_key(struct seq_file *p, key_serial_t id)
+{
+	struct user_namespace *user_ns = seq_user_ns(p);
+	struct rb_node *n = key_serial_tree.rb_node;
+	struct key *minkey = NULL;
+
+	while (n) {
+		struct key *key = rb_entry(n, struct key, serial_node);
+		if (id < key->serial) {
+			if (!minkey || minkey->serial > key->serial)
+				minkey = key;
+			n = n->rb_left;
+		} else if (id > key->serial) {
+			n = n->rb_right;
+		} else {
+			minkey = key;
+			break;
+		}
+		key = NULL;
+	}
+
+	if (!minkey)
+		return NULL;
+
+	for (;;) {
+		if (kuid_has_mapping(user_ns, minkey->user->uid))
+			return minkey;
+		n = rb_next(&minkey->serial_node);
+		if (!n)
+			return NULL;
+		minkey = rb_entry(n, struct key, serial_node);
+	}
+}
+
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
+	__acquires(key_serial_lock)
+{
+	key_serial_t pos = *_pos;
+	struct key *key;
+
+	spin_lock(&key_serial_lock);
+
+	if (*_pos > INT_MAX)
+		return NULL;
+	key = find_ge_key(p, pos);
+	if (!key)
+		return NULL;
+	*_pos = key->serial;
+	return &key->serial_node;
+}
+
+static inline key_serial_t key_node_serial(struct rb_node *n)
+{
+	struct key *key = rb_entry(n, struct key, serial_node);
+	return key->serial;
+}
+
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+	struct rb_node *n;
+
+	n = key_serial_next(p, v);
+	if (n)
+		*_pos = key_node_serial(n);
+	else
+		(*_pos)++;
+	return n;
+}
+
+static void proc_keys_stop(struct seq_file *p, void *v)
+	__releases(key_serial_lock)
+{
+	spin_unlock(&key_serial_lock);
+}
+
+static int proc_keys_show(struct seq_file *m, void *v)
+{
+	struct rb_node *_p = v;
+	struct key *key = rb_entry(_p, struct key, serial_node);
+	unsigned long flags;
+	key_ref_t key_ref, skey_ref;
+	time64_t now, expiry;
+	char xbuf[16];
+	short state;
+	u64 timo;
+	int rc;
+
+	struct keyring_search_context ctx = {
+		.index_key		= key->index_key,
+		.cred			= m->file->f_cred,
+		.match_data.cmp		= lookup_user_key_possessed,
+		.match_data.raw_data	= key,
+		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
+		.flags			= KEYRING_SEARCH_NO_STATE_CHECK,
+	};
+
+	key_ref = make_key_ref(key, 0);
+
+	/* determine if the key is possessed by this process (a test we can
+	 * skip if the key does not indicate the possessor can view it
+	 */
+	if (key->perm & KEY_POS_VIEW) {
+		skey_ref = search_my_process_keyrings(&ctx);
+		if (!IS_ERR(skey_ref)) {
+			key_ref_put(skey_ref);
+			key_ref = make_key_ref(key, 1);
+		}
+	}
+
+	/* check whether the current task is allowed to view the key */
+	rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
+	if (rc < 0)
+		return 0;
+
+	now = ktime_get_real_seconds();
+
+	rcu_read_lock();
+
+	/* come up with a suitable timeout value */
+	expiry = READ_ONCE(key->expiry);
+	if (expiry == 0) {
+		memcpy(xbuf, "perm", 5);
+	} else if (now >= expiry) {
+		memcpy(xbuf, "expd", 5);
+	} else {
+		timo = expiry - now;
+
+		if (timo < 60)
+			sprintf(xbuf, "%llus", timo);
+		else if (timo < 60*60)
+			sprintf(xbuf, "%llum", div_u64(timo, 60));
+		else if (timo < 60*60*24)
+			sprintf(xbuf, "%lluh", div_u64(timo, 60 * 60));
+		else if (timo < 60*60*24*7)
+			sprintf(xbuf, "%llud", div_u64(timo, 60 * 60 * 24));
+		else
+			sprintf(xbuf, "%lluw", div_u64(timo, 60 * 60 * 24 * 7));
+	}
+
+	state = key_read_state(key);
+
+#define showflag(FLAGS, LETTER, FLAG) \
+	((FLAGS & (1 << FLAG)) ? LETTER : '-')
+
+	flags = READ_ONCE(key->flags);
+	seq_printf(m, "%08x %c%c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
+		   key->serial,
+		   state != KEY_IS_UNINSTANTIATED ? 'I' : '-',
+		   showflag(flags, 'R', KEY_FLAG_REVOKED),
+		   showflag(flags, 'D', KEY_FLAG_DEAD),
+		   showflag(flags, 'Q', KEY_FLAG_IN_QUOTA),
+		   showflag(flags, 'U', KEY_FLAG_USER_CONSTRUCT),
+		   state < 0 ? 'N' : '-',
+		   showflag(flags, 'i', KEY_FLAG_INVALIDATED),
+		   refcount_read(&key->usage),
+		   xbuf,
+		   key->perm,
+		   from_kuid_munged(seq_user_ns(m), key->uid),
+		   from_kgid_munged(seq_user_ns(m), key->gid),
+		   key->type->name);
+
+#undef showflag
+
+	if (key->type->describe)
+		key->type->describe(key, m);
+	seq_putc(m, '\n');
+
+	rcu_read_unlock();
+	return 0;
+}
+
+static struct rb_node *__key_user_next(struct user_namespace *user_ns, struct rb_node *n)
+{
+	while (n) {
+		struct key_user *user = rb_entry(n, struct key_user, node);
+		if (kuid_has_mapping(user_ns, user->uid))
+			break;
+		n = rb_next(n);
+	}
+	return n;
+}
+
+static struct rb_node *key_user_next(struct user_namespace *user_ns, struct rb_node *n)
+{
+	return __key_user_next(user_ns, rb_next(n));
+}
+
+static struct rb_node *key_user_first(struct user_namespace *user_ns, struct rb_root *r)
+{
+	struct rb_node *n = rb_first(r);
+	return __key_user_next(user_ns, n);
+}
+
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
+	__acquires(key_user_lock)
+{
+	struct rb_node *_p;
+	loff_t pos = *_pos;
+
+	spin_lock(&key_user_lock);
+
+	_p = key_user_first(seq_user_ns(p), &key_user_tree);
+	while (pos > 0 && _p) {
+		pos--;
+		_p = key_user_next(seq_user_ns(p), _p);
+	}
+
+	return _p;
+}
+
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+	(*_pos)++;
+	return key_user_next(seq_user_ns(p), (struct rb_node *)v);
+}
+
+static void proc_key_users_stop(struct seq_file *p, void *v)
+	__releases(key_user_lock)
+{
+	spin_unlock(&key_user_lock);
+}
+
+static int proc_key_users_show(struct seq_file *m, void *v)
+{
+	struct rb_node *_p = v;
+	struct key_user *user = rb_entry(_p, struct key_user, node);
+	unsigned maxkeys = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
+		key_quota_root_maxkeys : key_quota_maxkeys;
+	unsigned maxbytes = uid_eq(user->uid, GLOBAL_ROOT_UID) ?
+		key_quota_root_maxbytes : key_quota_maxbytes;
+
+	seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
+		   from_kuid_munged(seq_user_ns(m), user->uid),
+		   refcount_read(&user->usage),
+		   atomic_read(&user->nkeys),
+		   atomic_read(&user->nikeys),
+		   user->qnkeys,
+		   maxkeys,
+		   user->qnbytes,
+		   maxbytes);
+
+	return 0;
+}
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
new file mode 100644
index 000000000..d776d2114
--- /dev/null
+++ b/security/keys/process_keys.c
@@ -0,0 +1,891 @@
+/* Manage a process's keyrings
+ *
+ * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/sched/user.h>
+#include <linux/keyctl.h>
+#include <linux/fs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/security.h>
+#include <linux/user_namespace.h>
+#include <linux/uaccess.h>
+#include <keys/request_key_auth-type.h>
+#include "internal.h"
+
+/* Session keyring create vs join semaphore */
+static DEFINE_MUTEX(key_session_mutex);
+
+/* User keyring creation semaphore */
+static DEFINE_MUTEX(key_user_keyring_mutex);
+
+/* The root user's tracking struct */
+struct key_user root_key_user = {
+	.usage		= REFCOUNT_INIT(3),
+	.cons_lock	= __MUTEX_INITIALIZER(root_key_user.cons_lock),
+	.lock		= __SPIN_LOCK_UNLOCKED(root_key_user.lock),
+	.nkeys		= ATOMIC_INIT(2),
+	.nikeys		= ATOMIC_INIT(2),
+	.uid		= GLOBAL_ROOT_UID,
+};
+
+/*
+ * Install the user and user session keyrings for the current process's UID.
+ */
+int install_user_keyrings(void)
+{
+	struct user_struct *user;
+	const struct cred *cred;
+	struct key *uid_keyring, *session_keyring;
+	key_perm_t user_keyring_perm;
+	char buf[20];
+	int ret;
+	uid_t uid;
+
+	user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL;
+	cred = current_cred();
+	user = cred->user;
+	uid = from_kuid(cred->user_ns, user->uid);
+
+	kenter("%p{%u}", user, uid);
+
+	if (user->uid_keyring && user->session_keyring) {
+		kleave(" = 0 [exist]");
+		return 0;
+	}
+
+	mutex_lock(&key_user_keyring_mutex);
+	ret = 0;
+
+	if (!user->uid_keyring) {
+		/* get the UID-specific keyring
+		 * - there may be one in existence already as it may have been
+		 *   pinned by a session, but the user_struct pointing to it
+		 *   may have been destroyed by setuid */
+		sprintf(buf, "_uid.%u", uid);
+
+		uid_keyring = find_keyring_by_name(buf, true);
+		if (IS_ERR(uid_keyring)) {
+			uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID,
+						    cred, user_keyring_perm,
+						    KEY_ALLOC_UID_KEYRING |
+							KEY_ALLOC_IN_QUOTA,
+						    NULL, NULL);
+			if (IS_ERR(uid_keyring)) {
+				ret = PTR_ERR(uid_keyring);
+				goto error;
+			}
+		}
+
+		/* get a default session keyring (which might also exist
+		 * already) */
+		sprintf(buf, "_uid_ses.%u", uid);
+
+		session_keyring = find_keyring_by_name(buf, true);
+		if (IS_ERR(session_keyring)) {
+			session_keyring =
+				keyring_alloc(buf, user->uid, INVALID_GID,
+					      cred, user_keyring_perm,
+					      KEY_ALLOC_UID_KEYRING |
+						  KEY_ALLOC_IN_QUOTA,
+					      NULL, NULL);
+			if (IS_ERR(session_keyring)) {
+				ret = PTR_ERR(session_keyring);
+				goto error_release;
+			}
+
+			/* we install a link from the user session keyring to
+			 * the user keyring */
+			ret = key_link(session_keyring, uid_keyring);
+			if (ret < 0)
+				goto error_release_both;
+		}
+
+		/* install the keyrings */
+		user->uid_keyring = uid_keyring;
+		user->session_keyring = session_keyring;
+	}
+
+	mutex_unlock(&key_user_keyring_mutex);
+	kleave(" = 0");
+	return 0;
+
+error_release_both:
+	key_put(session_keyring);
+error_release:
+	key_put(uid_keyring);
+error:
+	mutex_unlock(&key_user_keyring_mutex);
+	kleave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Install a thread keyring to the given credentials struct if it didn't have
+ * one already.  This is allowed to overrun the quota.
+ *
+ * Return: 0 if a thread keyring is now present; -errno on failure.
+ */
+int install_thread_keyring_to_cred(struct cred *new)
+{
+	struct key *keyring;
+
+	if (new->thread_keyring)
+		return 0;
+
+	keyring = keyring_alloc("_tid", new->uid, new->gid, new,
+				KEY_POS_ALL | KEY_USR_VIEW,
+				KEY_ALLOC_QUOTA_OVERRUN,
+				NULL, NULL);
+	if (IS_ERR(keyring))
+		return PTR_ERR(keyring);
+
+	new->thread_keyring = keyring;
+	return 0;
+}
+
+/*
+ * Install a thread keyring to the current task if it didn't have one already.
+ *
+ * Return: 0 if a thread keyring is now present; -errno on failure.
+ */
+static int install_thread_keyring(void)
+{
+	struct cred *new;
+	int ret;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	ret = install_thread_keyring_to_cred(new);
+	if (ret < 0) {
+		abort_creds(new);
+		return ret;
+	}
+
+	return commit_creds(new);
+}
+
+/*
+ * Install a process keyring to the given credentials struct if it didn't have
+ * one already.  This is allowed to overrun the quota.
+ *
+ * Return: 0 if a process keyring is now present; -errno on failure.
+ */
+int install_process_keyring_to_cred(struct cred *new)
+{
+	struct key *keyring;
+
+	if (new->process_keyring)
+		return 0;
+
+	keyring = keyring_alloc("_pid", new->uid, new->gid, new,
+				KEY_POS_ALL | KEY_USR_VIEW,
+				KEY_ALLOC_QUOTA_OVERRUN,
+				NULL, NULL);
+	if (IS_ERR(keyring))
+		return PTR_ERR(keyring);
+
+	new->process_keyring = keyring;
+	return 0;
+}
+
+/*
+ * Install a process keyring to the current task if it didn't have one already.
+ *
+ * Return: 0 if a process keyring is now present; -errno on failure.
+ */
+static int install_process_keyring(void)
+{
+	struct cred *new;
+	int ret;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	ret = install_process_keyring_to_cred(new);
+	if (ret < 0) {
+		abort_creds(new);
+		return ret;
+	}
+
+	return commit_creds(new);
+}
+
+/*
+ * Install the given keyring as the session keyring of the given credentials
+ * struct, replacing the existing one if any.  If the given keyring is NULL,
+ * then install a new anonymous session keyring.
+ *
+ * Return: 0 on success; -errno on failure.
+ */
+int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
+{
+	unsigned long flags;
+	struct key *old;
+
+	might_sleep();
+
+	/* create an empty session keyring */
+	if (!keyring) {
+		flags = KEY_ALLOC_QUOTA_OVERRUN;
+		if (cred->session_keyring)
+			flags = KEY_ALLOC_IN_QUOTA;
+
+		keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred,
+					KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ,
+					flags, NULL, NULL);
+		if (IS_ERR(keyring))
+			return PTR_ERR(keyring);
+	} else {
+		__key_get(keyring);
+	}
+
+	/* install the keyring */
+	old = cred->session_keyring;
+	rcu_assign_pointer(cred->session_keyring, keyring);
+
+	if (old)
+		key_put(old);
+
+	return 0;
+}
+
+/*
+ * Install the given keyring as the session keyring of the current task,
+ * replacing the existing one if any.  If the given keyring is NULL, then
+ * install a new anonymous session keyring.
+ *
+ * Return: 0 on success; -errno on failure.
+ */
+static int install_session_keyring(struct key *keyring)
+{
+	struct cred *new;
+	int ret;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	ret = install_session_keyring_to_cred(new, keyring);
+	if (ret < 0) {
+		abort_creds(new);
+		return ret;
+	}
+
+	return commit_creds(new);
+}
+
+/*
+ * Handle the fsuid changing.
+ */
+void key_fsuid_changed(struct task_struct *tsk)
+{
+	/* update the ownership of the thread keyring */
+	BUG_ON(!tsk->cred);
+	if (tsk->cred->thread_keyring) {
+		down_write(&tsk->cred->thread_keyring->sem);
+		tsk->cred->thread_keyring->uid = tsk->cred->fsuid;
+		up_write(&tsk->cred->thread_keyring->sem);
+	}
+}
+
+/*
+ * Handle the fsgid changing.
+ */
+void key_fsgid_changed(struct task_struct *tsk)
+{
+	/* update the ownership of the thread keyring */
+	BUG_ON(!tsk->cred);
+	if (tsk->cred->thread_keyring) {
+		down_write(&tsk->cred->thread_keyring->sem);
+		tsk->cred->thread_keyring->gid = tsk->cred->fsgid;
+		up_write(&tsk->cred->thread_keyring->sem);
+	}
+}
+
+/*
+ * Search the process keyrings attached to the supplied cred for the first
+ * matching key.
+ *
+ * The search criteria are the type and the match function.  The description is
+ * given to the match function as a parameter, but doesn't otherwise influence
+ * the search.  Typically the match function will compare the description
+ * parameter to the key's description.
+ *
+ * This can only search keyrings that grant Search permission to the supplied
+ * credentials.  Keyrings linked to searched keyrings will also be searched if
+ * they grant Search permission too.  Keys can only be found if they grant
+ * Search permission to the credentials.
+ *
+ * Returns a pointer to the key with the key usage count incremented if
+ * successful, -EAGAIN if we didn't find any matching key or -ENOKEY if we only
+ * matched negative keys.
+ *
+ * In the case of a successful return, the possession attribute is set on the
+ * returned key reference.
+ */
+key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx)
+{
+	key_ref_t key_ref, ret, err;
+
+	/* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
+	 * searchable, but we failed to find a key or we found a negative key;
+	 * otherwise we want to return a sample error (probably -EACCES) if
+	 * none of the keyrings were searchable
+	 *
+	 * in terms of priority: success > -ENOKEY > -EAGAIN > other error
+	 */
+	key_ref = NULL;
+	ret = NULL;
+	err = ERR_PTR(-EAGAIN);
+
+	/* search the thread keyring first */
+	if (ctx->cred->thread_keyring) {
+		key_ref = keyring_search_aux(
+			make_key_ref(ctx->cred->thread_keyring, 1), ctx);
+		if (!IS_ERR(key_ref))
+			goto found;
+
+		switch (PTR_ERR(key_ref)) {
+		case -EAGAIN: /* no key */
+		case -ENOKEY: /* negative key */
+			ret = key_ref;
+			break;
+		default:
+			err = key_ref;
+			break;
+		}
+	}
+
+	/* search the process keyring second */
+	if (ctx->cred->process_keyring) {
+		key_ref = keyring_search_aux(
+			make_key_ref(ctx->cred->process_keyring, 1), ctx);
+		if (!IS_ERR(key_ref))
+			goto found;
+
+		switch (PTR_ERR(key_ref)) {
+		case -EAGAIN: /* no key */
+			if (ret)
+				break;
+		case -ENOKEY: /* negative key */
+			ret = key_ref;
+			break;
+		default:
+			err = key_ref;
+			break;
+		}
+	}
+
+	/* search the session keyring */
+	if (ctx->cred->session_keyring) {
+		rcu_read_lock();
+		key_ref = keyring_search_aux(
+			make_key_ref(rcu_dereference(ctx->cred->session_keyring), 1),
+			ctx);
+		rcu_read_unlock();
+
+		if (!IS_ERR(key_ref))
+			goto found;
+
+		switch (PTR_ERR(key_ref)) {
+		case -EAGAIN: /* no key */
+			if (ret)
+				break;
+		case -ENOKEY: /* negative key */
+			ret = key_ref;
+			break;
+		default:
+			err = key_ref;
+			break;
+		}
+	}
+	/* or search the user-session keyring */
+	else if (ctx->cred->user->session_keyring) {
+		key_ref = keyring_search_aux(
+			make_key_ref(ctx->cred->user->session_keyring, 1),
+			ctx);
+		if (!IS_ERR(key_ref))
+			goto found;
+
+		switch (PTR_ERR(key_ref)) {
+		case -EAGAIN: /* no key */
+			if (ret)
+				break;
+		case -ENOKEY: /* negative key */
+			ret = key_ref;
+			break;
+		default:
+			err = key_ref;
+			break;
+		}
+	}
+
+	/* no key - decide on the error we're going to go for */
+	key_ref = ret ? ret : err;
+
+found:
+	return key_ref;
+}
+
+/*
+ * Search the process keyrings attached to the supplied cred for the first
+ * matching key in the manner of search_my_process_keyrings(), but also search
+ * the keys attached to the assumed authorisation key using its credentials if
+ * one is available.
+ *
+ * Return same as search_my_process_keyrings().
+ */
+key_ref_t search_process_keyrings(struct keyring_search_context *ctx)
+{
+	struct request_key_auth *rka;
+	key_ref_t key_ref, ret = ERR_PTR(-EACCES), err;
+
+	might_sleep();
+
+	key_ref = search_my_process_keyrings(ctx);
+	if (!IS_ERR(key_ref))
+		goto found;
+	err = key_ref;
+
+	/* if this process has an instantiation authorisation key, then we also
+	 * search the keyrings of the process mentioned there
+	 * - we don't permit access to request_key auth keys via this method
+	 */
+	if (ctx->cred->request_key_auth &&
+	    ctx->cred == current_cred() &&
+	    ctx->index_key.type != &key_type_request_key_auth
+	    ) {
+		const struct cred *cred = ctx->cred;
+
+		/* defend against the auth key being revoked */
+		down_read(&cred->request_key_auth->sem);
+
+		if (key_validate(ctx->cred->request_key_auth) == 0) {
+			rka = ctx->cred->request_key_auth->payload.data[0];
+
+			ctx->cred = rka->cred;
+			key_ref = search_process_keyrings(ctx);
+			ctx->cred = cred;
+
+			up_read(&cred->request_key_auth->sem);
+
+			if (!IS_ERR(key_ref))
+				goto found;
+
+			ret = key_ref;
+		} else {
+			up_read(&cred->request_key_auth->sem);
+		}
+	}
+
+	/* no key - decide on the error we're going to go for */
+	if (err == ERR_PTR(-ENOKEY) || ret == ERR_PTR(-ENOKEY))
+		key_ref = ERR_PTR(-ENOKEY);
+	else if (err == ERR_PTR(-EACCES))
+		key_ref = ret;
+	else
+		key_ref = err;
+
+found:
+	return key_ref;
+}
+
+/*
+ * See if the key we're looking at is the target key.
+ */
+bool lookup_user_key_possessed(const struct key *key,
+			       const struct key_match_data *match_data)
+{
+	return key == match_data->raw_data;
+}
+
+/*
+ * Look up a key ID given us by userspace with a given permissions mask to get
+ * the key it refers to.
+ *
+ * Flags can be passed to request that special keyrings be created if referred
+ * to directly, to permit partially constructed keys to be found and to skip
+ * validity and permission checks on the found key.
+ *
+ * Returns a pointer to the key with an incremented usage count if successful;
+ * -EINVAL if the key ID is invalid; -ENOKEY if the key ID does not correspond
+ * to a key or the best found key was a negative key; -EKEYREVOKED or
+ * -EKEYEXPIRED if the best found key was revoked or expired; -EACCES if the
+ * found key doesn't grant the requested permit or the LSM denied access to it;
+ * or -ENOMEM if a special keyring couldn't be created.
+ *
+ * In the case of a successful return, the possession attribute is set on the
+ * returned key reference.
+ */
+key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
+			  key_perm_t perm)
+{
+	struct keyring_search_context ctx = {
+		.match_data.cmp		= lookup_user_key_possessed,
+		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
+		.flags			= KEYRING_SEARCH_NO_STATE_CHECK,
+	};
+	struct request_key_auth *rka;
+	struct key *key;
+	key_ref_t key_ref, skey_ref;
+	int ret;
+
+try_again:
+	ctx.cred = get_current_cred();
+	key_ref = ERR_PTR(-ENOKEY);
+
+	switch (id) {
+	case KEY_SPEC_THREAD_KEYRING:
+		if (!ctx.cred->thread_keyring) {
+			if (!(lflags & KEY_LOOKUP_CREATE))
+				goto error;
+
+			ret = install_thread_keyring();
+			if (ret < 0) {
+				key_ref = ERR_PTR(ret);
+				goto error;
+			}
+			goto reget_creds;
+		}
+
+		key = ctx.cred->thread_keyring;
+		__key_get(key);
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_PROCESS_KEYRING:
+		if (!ctx.cred->process_keyring) {
+			if (!(lflags & KEY_LOOKUP_CREATE))
+				goto error;
+
+			ret = install_process_keyring();
+			if (ret < 0) {
+				key_ref = ERR_PTR(ret);
+				goto error;
+			}
+			goto reget_creds;
+		}
+
+		key = ctx.cred->process_keyring;
+		__key_get(key);
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_SESSION_KEYRING:
+		if (!ctx.cred->session_keyring) {
+			/* always install a session keyring upon access if one
+			 * doesn't exist yet */
+			ret = install_user_keyrings();
+			if (ret < 0)
+				goto error;
+			if (lflags & KEY_LOOKUP_CREATE)
+				ret = join_session_keyring(NULL);
+			else
+				ret = install_session_keyring(
+					ctx.cred->user->session_keyring);
+
+			if (ret < 0)
+				goto error;
+			goto reget_creds;
+		} else if (ctx.cred->session_keyring ==
+			   ctx.cred->user->session_keyring &&
+			   lflags & KEY_LOOKUP_CREATE) {
+			ret = join_session_keyring(NULL);
+			if (ret < 0)
+				goto error;
+			goto reget_creds;
+		}
+
+		rcu_read_lock();
+		key = rcu_dereference(ctx.cred->session_keyring);
+		__key_get(key);
+		rcu_read_unlock();
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_USER_KEYRING:
+		if (!ctx.cred->user->uid_keyring) {
+			ret = install_user_keyrings();
+			if (ret < 0)
+				goto error;
+		}
+
+		key = ctx.cred->user->uid_keyring;
+		__key_get(key);
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_USER_SESSION_KEYRING:
+		if (!ctx.cred->user->session_keyring) {
+			ret = install_user_keyrings();
+			if (ret < 0)
+				goto error;
+		}
+
+		key = ctx.cred->user->session_keyring;
+		__key_get(key);
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_GROUP_KEYRING:
+		/* group keyrings are not yet supported */
+		key_ref = ERR_PTR(-EINVAL);
+		goto error;
+
+	case KEY_SPEC_REQKEY_AUTH_KEY:
+		key = ctx.cred->request_key_auth;
+		if (!key)
+			goto error;
+
+		__key_get(key);
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	case KEY_SPEC_REQUESTOR_KEYRING:
+		if (!ctx.cred->request_key_auth)
+			goto error;
+
+		down_read(&ctx.cred->request_key_auth->sem);
+		if (test_bit(KEY_FLAG_REVOKED,
+			     &ctx.cred->request_key_auth->flags)) {
+			key_ref = ERR_PTR(-EKEYREVOKED);
+			key = NULL;
+		} else {
+			rka = ctx.cred->request_key_auth->payload.data[0];
+			key = rka->dest_keyring;
+			__key_get(key);
+		}
+		up_read(&ctx.cred->request_key_auth->sem);
+		if (!key)
+			goto error;
+		key_ref = make_key_ref(key, 1);
+		break;
+
+	default:
+		key_ref = ERR_PTR(-EINVAL);
+		if (id < 1)
+			goto error;
+
+		key = key_lookup(id);
+		if (IS_ERR(key)) {
+			key_ref = ERR_CAST(key);
+			goto error;
+		}
+
+		key_ref = make_key_ref(key, 0);
+
+		/* check to see if we possess the key */
+		ctx.index_key.type		= key->type;
+		ctx.index_key.description	= key->description;
+		ctx.index_key.desc_len		= strlen(key->description);
+		ctx.match_data.raw_data		= key;
+		kdebug("check possessed");
+		skey_ref = search_process_keyrings(&ctx);
+		kdebug("possessed=%p", skey_ref);
+
+		if (!IS_ERR(skey_ref)) {
+			key_put(key);
+			key_ref = skey_ref;
+		}
+
+		break;
+	}
+
+	/* unlink does not use the nominated key in any way, so can skip all
+	 * the permission checks as it is only concerned with the keyring */
+	if (lflags & KEY_LOOKUP_FOR_UNLINK) {
+		ret = 0;
+		goto error;
+	}
+
+	if (!(lflags & KEY_LOOKUP_PARTIAL)) {
+		ret = wait_for_key_construction(key, true);
+		switch (ret) {
+		case -ERESTARTSYS:
+			goto invalid_key;
+		default:
+			if (perm)
+				goto invalid_key;
+		case 0:
+			break;
+		}
+	} else if (perm) {
+		ret = key_validate(key);
+		if (ret < 0)
+			goto invalid_key;
+	}
+
+	ret = -EIO;
+	if (!(lflags & KEY_LOOKUP_PARTIAL) &&
+	    key_read_state(key) == KEY_IS_UNINSTANTIATED)
+		goto invalid_key;
+
+	/* check the permissions */
+	ret = key_task_permission(key_ref, ctx.cred, perm);
+	if (ret < 0)
+		goto invalid_key;
+
+	key->last_used_at = ktime_get_real_seconds();
+
+error:
+	put_cred(ctx.cred);
+	return key_ref;
+
+invalid_key:
+	key_ref_put(key_ref);
+	key_ref = ERR_PTR(ret);
+	goto error;
+
+	/* if we attempted to install a keyring, then it may have caused new
+	 * creds to be installed */
+reget_creds:
+	put_cred(ctx.cred);
+	goto try_again;
+}
+
+/*
+ * Join the named keyring as the session keyring if possible else attempt to
+ * create a new one of that name and join that.
+ *
+ * If the name is NULL, an empty anonymous keyring will be installed as the
+ * session keyring.
+ *
+ * Named session keyrings are joined with a semaphore held to prevent the
+ * keyrings from going away whilst the attempt is made to going them and also
+ * to prevent a race in creating compatible session keyrings.
+ */
+long join_session_keyring(const char *name)
+{
+	const struct cred *old;
+	struct cred *new;
+	struct key *keyring;
+	long ret, serial;
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+	old = current_cred();
+
+	/* if no name is provided, install an anonymous keyring */
+	if (!name) {
+		ret = install_session_keyring_to_cred(new, NULL);
+		if (ret < 0)
+			goto error;
+
+		serial = new->session_keyring->serial;
+		ret = commit_creds(new);
+		if (ret == 0)
+			ret = serial;
+		goto okay;
+	}
+
+	/* allow the user to join or create a named keyring */
+	mutex_lock(&key_session_mutex);
+
+	/* look for an existing keyring of this name */
+	keyring = find_keyring_by_name(name, false);
+	if (PTR_ERR(keyring) == -ENOKEY) {
+		/* not found - try and create a new one */
+		keyring = keyring_alloc(
+			name, old->uid, old->gid, old,
+			KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_LINK,
+			KEY_ALLOC_IN_QUOTA, NULL, NULL);
+		if (IS_ERR(keyring)) {
+			ret = PTR_ERR(keyring);
+			goto error2;
+		}
+	} else if (IS_ERR(keyring)) {
+		ret = PTR_ERR(keyring);
+		goto error2;
+	} else if (keyring == new->session_keyring) {
+		ret = 0;
+		goto error3;
+	}
+
+	/* we've got a keyring - now to install it */
+	ret = install_session_keyring_to_cred(new, keyring);
+	if (ret < 0)
+		goto error3;
+
+	commit_creds(new);
+	mutex_unlock(&key_session_mutex);
+
+	ret = keyring->serial;
+	key_put(keyring);
+okay:
+	return ret;
+
+error3:
+	key_put(keyring);
+error2:
+	mutex_unlock(&key_session_mutex);
+error:
+	abort_creds(new);
+	return ret;
+}
+
+/*
+ * Replace a process's session keyring on behalf of one of its children when
+ * the target  process is about to resume userspace execution.
+ */
+void key_change_session_keyring(struct callback_head *twork)
+{
+	const struct cred *old = current_cred();
+	struct cred *new = container_of(twork, struct cred, rcu);
+
+	if (unlikely(current->flags & PF_EXITING)) {
+		put_cred(new);
+		return;
+	}
+
+	new->  uid	= old->  uid;
+	new-> euid	= old-> euid;
+	new-> suid	= old-> suid;
+	new->fsuid	= old->fsuid;
+	new->  gid	= old->  gid;
+	new-> egid	= old-> egid;
+	new-> sgid	= old-> sgid;
+	new->fsgid	= old->fsgid;
+	new->user	= get_uid(old->user);
+	new->user_ns	= get_user_ns(old->user_ns);
+	new->group_info	= get_group_info(old->group_info);
+
+	new->securebits	= old->securebits;
+	new->cap_inheritable	= old->cap_inheritable;
+	new->cap_permitted	= old->cap_permitted;
+	new->cap_effective	= old->cap_effective;
+	new->cap_ambient	= old->cap_ambient;
+	new->cap_bset		= old->cap_bset;
+
+	new->jit_keyring	= old->jit_keyring;
+	new->thread_keyring	= key_get(old->thread_keyring);
+	new->process_keyring	= key_get(old->process_keyring);
+
+	security_transfer_creds(new, old);
+
+	commit_creds(new);
+}
+
+/*
+ * Make sure that root's user and user-session keyrings exist.
+ */
+static int __init init_root_keyring(void)
+{
+	return install_user_keyrings();
+}
+
+late_initcall(init_root_keyring);
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
new file mode 100644
index 000000000..1a547cec8
--- /dev/null
+++ b/security/keys/request_key.c
@@ -0,0 +1,739 @@
+/* Request a key from userspace
+ *
+ * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * See Documentation/security/keys/request-key.rst
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kmod.h>
+#include <linux/err.h>
+#include <linux/keyctl.h>
+#include <linux/slab.h>
+#include "internal.h"
+#include <keys/request_key_auth-type.h>
+
+#define key_negative_timeout	60	/* default timeout on a negative key's existence */
+
+/**
+ * complete_request_key - Complete the construction of a key.
+ * @auth_key: The authorisation key.
+ * @error: The success or failute of the construction.
+ *
+ * Complete the attempt to construct a key.  The key will be negated
+ * if an error is indicated.  The authorisation key will be revoked
+ * unconditionally.
+ */
+void complete_request_key(struct key *authkey, int error)
+{
+	struct request_key_auth *rka = get_request_key_auth(authkey);
+	struct key *key = rka->target_key;
+
+	kenter("%d{%d},%d", authkey->serial, key->serial, error);
+
+	if (error < 0)
+		key_negate_and_link(key, key_negative_timeout, NULL, authkey);
+	else
+		key_revoke(authkey);
+}
+EXPORT_SYMBOL(complete_request_key);
+
+/*
+ * Initialise a usermode helper that is going to have a specific session
+ * keyring.
+ *
+ * This is called in context of freshly forked kthread before kernel_execve(),
+ * so we can simply install the desired session_keyring at this point.
+ */
+static int umh_keys_init(struct subprocess_info *info, struct cred *cred)
+{
+	struct key *keyring = info->data;
+
+	return install_session_keyring_to_cred(cred, keyring);
+}
+
+/*
+ * Clean up a usermode helper with session keyring.
+ */
+static void umh_keys_cleanup(struct subprocess_info *info)
+{
+	struct key *keyring = info->data;
+	key_put(keyring);
+}
+
+/*
+ * Call a usermode helper with a specific session keyring.
+ */
+static int call_usermodehelper_keys(const char *path, char **argv, char **envp,
+					struct key *session_keyring, int wait)
+{
+	struct subprocess_info *info;
+
+	info = call_usermodehelper_setup(path, argv, envp, GFP_KERNEL,
+					  umh_keys_init, umh_keys_cleanup,
+					  session_keyring);
+	if (!info)
+		return -ENOMEM;
+
+	key_get(session_keyring);
+	return call_usermodehelper_exec(info, wait);
+}
+
+/*
+ * Request userspace finish the construction of a key
+ * - execute "/sbin/request-key <op> <key> <uid> <gid> <keyring> <keyring> <keyring>"
+ */
+static int call_sbin_request_key(struct key *authkey, void *aux)
+{
+	static char const request_key[] = "/sbin/request-key";
+	struct request_key_auth *rka = get_request_key_auth(authkey);
+	const struct cred *cred = current_cred();
+	key_serial_t prkey, sskey;
+	struct key *key = rka->target_key, *keyring, *session;
+	char *argv[9], *envp[3], uid_str[12], gid_str[12];
+	char key_str[12], keyring_str[3][12];
+	char desc[20];
+	int ret, i;
+
+	kenter("{%d},{%d},%s", key->serial, authkey->serial, rka->op);
+
+	ret = install_user_keyrings();
+	if (ret < 0)
+		goto error_alloc;
+
+	/* allocate a new session keyring */
+	sprintf(desc, "_req.%u", key->serial);
+
+	cred = get_current_cred();
+	keyring = keyring_alloc(desc, cred->fsuid, cred->fsgid, cred,
+				KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ,
+				KEY_ALLOC_QUOTA_OVERRUN, NULL, NULL);
+	put_cred(cred);
+	if (IS_ERR(keyring)) {
+		ret = PTR_ERR(keyring);
+		goto error_alloc;
+	}
+
+	/* attach the auth key to the session keyring */
+	ret = key_link(keyring, authkey);
+	if (ret < 0)
+		goto error_link;
+
+	/* record the UID and GID */
+	sprintf(uid_str, "%d", from_kuid(&init_user_ns, cred->fsuid));
+	sprintf(gid_str, "%d", from_kgid(&init_user_ns, cred->fsgid));
+
+	/* we say which key is under construction */
+	sprintf(key_str, "%d", key->serial);
+
+	/* we specify the process's default keyrings */
+	sprintf(keyring_str[0], "%d",
+		cred->thread_keyring ? cred->thread_keyring->serial : 0);
+
+	prkey = 0;
+	if (cred->process_keyring)
+		prkey = cred->process_keyring->serial;
+	sprintf(keyring_str[1], "%d", prkey);
+
+	rcu_read_lock();
+	session = rcu_dereference(cred->session_keyring);
+	if (!session)
+		session = cred->user->session_keyring;
+	sskey = session->serial;
+	rcu_read_unlock();
+
+	sprintf(keyring_str[2], "%d", sskey);
+
+	/* set up a minimal environment */
+	i = 0;
+	envp[i++] = "HOME=/";
+	envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+	envp[i] = NULL;
+
+	/* set up the argument list */
+	i = 0;
+	argv[i++] = (char *)request_key;
+	argv[i++] = (char *)rka->op;
+	argv[i++] = key_str;
+	argv[i++] = uid_str;
+	argv[i++] = gid_str;
+	argv[i++] = keyring_str[0];
+	argv[i++] = keyring_str[1];
+	argv[i++] = keyring_str[2];
+	argv[i] = NULL;
+
+	/* do it */
+	ret = call_usermodehelper_keys(request_key, argv, envp, keyring,
+				       UMH_WAIT_PROC);
+	kdebug("usermode -> 0x%x", ret);
+	if (ret >= 0) {
+		/* ret is the exit/wait code */
+		if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags) ||
+		    key_validate(key) < 0)
+			ret = -ENOKEY;
+		else
+			/* ignore any errors from userspace if the key was
+			 * instantiated */
+			ret = 0;
+	}
+
+error_link:
+	key_put(keyring);
+
+error_alloc:
+	complete_request_key(authkey, ret);
+	kleave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Call out to userspace for key construction.
+ *
+ * Program failure is ignored in favour of key status.
+ */
+static int construct_key(struct key *key, const void *callout_info,
+			 size_t callout_len, void *aux,
+			 struct key *dest_keyring)
+{
+	request_key_actor_t actor;
+	struct key *authkey;
+	int ret;
+
+	kenter("%d,%p,%zu,%p", key->serial, callout_info, callout_len, aux);
+
+	/* allocate an authorisation key */
+	authkey = request_key_auth_new(key, "create", callout_info, callout_len,
+				       dest_keyring);
+	if (IS_ERR(authkey))
+		return PTR_ERR(authkey);
+
+	/* Make the call */
+	actor = call_sbin_request_key;
+	if (key->type->request_key)
+		actor = key->type->request_key;
+
+	ret = actor(authkey, aux);
+
+	/* check that the actor called complete_request_key() prior to
+	 * returning an error */
+	WARN_ON(ret < 0 &&
+		!test_bit(KEY_FLAG_REVOKED, &authkey->flags));
+
+	key_put(authkey);
+	kleave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Get the appropriate destination keyring for the request.
+ *
+ * The keyring selected is returned with an extra reference upon it which the
+ * caller must release.
+ */
+static int construct_get_dest_keyring(struct key **_dest_keyring)
+{
+	struct request_key_auth *rka;
+	const struct cred *cred = current_cred();
+	struct key *dest_keyring = *_dest_keyring, *authkey;
+	int ret;
+
+	kenter("%p", dest_keyring);
+
+	/* find the appropriate keyring */
+	if (dest_keyring) {
+		/* the caller supplied one */
+		key_get(dest_keyring);
+	} else {
+		bool do_perm_check = true;
+
+		/* use a default keyring; falling through the cases until we
+		 * find one that we actually have */
+		switch (cred->jit_keyring) {
+		case KEY_REQKEY_DEFL_DEFAULT:
+		case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+			if (cred->request_key_auth) {
+				authkey = cred->request_key_auth;
+				down_read(&authkey->sem);
+				rka = get_request_key_auth(authkey);
+				if (!test_bit(KEY_FLAG_REVOKED,
+					      &authkey->flags))
+					dest_keyring =
+						key_get(rka->dest_keyring);
+				up_read(&authkey->sem);
+				if (dest_keyring) {
+					do_perm_check = false;
+					break;
+				}
+			}
+
+		case KEY_REQKEY_DEFL_THREAD_KEYRING:
+			dest_keyring = key_get(cred->thread_keyring);
+			if (dest_keyring)
+				break;
+
+		case KEY_REQKEY_DEFL_PROCESS_KEYRING:
+			dest_keyring = key_get(cred->process_keyring);
+			if (dest_keyring)
+				break;
+
+		case KEY_REQKEY_DEFL_SESSION_KEYRING:
+			rcu_read_lock();
+			dest_keyring = key_get(
+				rcu_dereference(cred->session_keyring));
+			rcu_read_unlock();
+
+			if (dest_keyring)
+				break;
+
+		case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
+			dest_keyring =
+				key_get(cred->user->session_keyring);
+			break;
+
+		case KEY_REQKEY_DEFL_USER_KEYRING:
+			dest_keyring = key_get(cred->user->uid_keyring);
+			break;
+
+		case KEY_REQKEY_DEFL_GROUP_KEYRING:
+		default:
+			BUG();
+		}
+
+		/*
+		 * Require Write permission on the keyring.  This is essential
+		 * because the default keyring may be the session keyring, and
+		 * joining a keyring only requires Search permission.
+		 *
+		 * However, this check is skipped for the "requestor keyring" so
+		 * that /sbin/request-key can itself use request_key() to add
+		 * keys to the original requestor's destination keyring.
+		 */
+		if (dest_keyring && do_perm_check) {
+			ret = key_permission(make_key_ref(dest_keyring, 1),
+					     KEY_NEED_WRITE);
+			if (ret) {
+				key_put(dest_keyring);
+				return ret;
+			}
+		}
+	}
+
+	*_dest_keyring = dest_keyring;
+	kleave(" [dk %d]", key_serial(dest_keyring));
+	return 0;
+}
+
+/*
+ * Allocate a new key in under-construction state and attempt to link it in to
+ * the requested keyring.
+ *
+ * May return a key that's already under construction instead if there was a
+ * race between two thread calling request_key().
+ */
+static int construct_alloc_key(struct keyring_search_context *ctx,
+			       struct key *dest_keyring,
+			       unsigned long flags,
+			       struct key_user *user,
+			       struct key **_key)
+{
+	struct assoc_array_edit *edit;
+	struct key *key;
+	key_perm_t perm;
+	key_ref_t key_ref;
+	int ret;
+
+	kenter("%s,%s,,,",
+	       ctx->index_key.type->name, ctx->index_key.description);
+
+	*_key = NULL;
+	mutex_lock(&user->cons_lock);
+
+	perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR;
+	perm |= KEY_USR_VIEW;
+	if (ctx->index_key.type->read)
+		perm |= KEY_POS_READ;
+	if (ctx->index_key.type == &key_type_keyring ||
+	    ctx->index_key.type->update)
+		perm |= KEY_POS_WRITE;
+
+	key = key_alloc(ctx->index_key.type, ctx->index_key.description,
+			ctx->cred->fsuid, ctx->cred->fsgid, ctx->cred,
+			perm, flags, NULL);
+	if (IS_ERR(key))
+		goto alloc_failed;
+
+	set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags);
+
+	if (dest_keyring) {
+		ret = __key_link_begin(dest_keyring, &ctx->index_key, &edit);
+		if (ret < 0)
+			goto link_prealloc_failed;
+	}
+
+	/* attach the key to the destination keyring under lock, but we do need
+	 * to do another check just in case someone beat us to it whilst we
+	 * waited for locks */
+	mutex_lock(&key_construction_mutex);
+
+	key_ref = search_process_keyrings(ctx);
+	if (!IS_ERR(key_ref))
+		goto key_already_present;
+
+	if (dest_keyring)
+		__key_link(key, &edit);
+
+	mutex_unlock(&key_construction_mutex);
+	if (dest_keyring)
+		__key_link_end(dest_keyring, &ctx->index_key, edit);
+	mutex_unlock(&user->cons_lock);
+	*_key = key;
+	kleave(" = 0 [%d]", key_serial(key));
+	return 0;
+
+	/* the key is now present - we tell the caller that we found it by
+	 * returning -EINPROGRESS  */
+key_already_present:
+	key_put(key);
+	mutex_unlock(&key_construction_mutex);
+	key = key_ref_to_ptr(key_ref);
+	if (dest_keyring) {
+		ret = __key_link_check_live_key(dest_keyring, key);
+		if (ret == 0)
+			__key_link(key, &edit);
+		__key_link_end(dest_keyring, &ctx->index_key, edit);
+		if (ret < 0)
+			goto link_check_failed;
+	}
+	mutex_unlock(&user->cons_lock);
+	*_key = key;
+	kleave(" = -EINPROGRESS [%d]", key_serial(key));
+	return -EINPROGRESS;
+
+link_check_failed:
+	mutex_unlock(&user->cons_lock);
+	key_put(key);
+	kleave(" = %d [linkcheck]", ret);
+	return ret;
+
+link_prealloc_failed:
+	mutex_unlock(&user->cons_lock);
+	key_put(key);
+	kleave(" = %d [prelink]", ret);
+	return ret;
+
+alloc_failed:
+	mutex_unlock(&user->cons_lock);
+	kleave(" = %ld", PTR_ERR(key));
+	return PTR_ERR(key);
+}
+
+/*
+ * Commence key construction.
+ */
+static struct key *construct_key_and_link(struct keyring_search_context *ctx,
+					  const char *callout_info,
+					  size_t callout_len,
+					  void *aux,
+					  struct key *dest_keyring,
+					  unsigned long flags)
+{
+	struct key_user *user;
+	struct key *key;
+	int ret;
+
+	kenter("");
+
+	if (ctx->index_key.type == &key_type_keyring)
+		return ERR_PTR(-EPERM);
+
+	ret = construct_get_dest_keyring(&dest_keyring);
+	if (ret)
+		goto error;
+
+	user = key_user_lookup(current_fsuid());
+	if (!user) {
+		ret = -ENOMEM;
+		goto error_put_dest_keyring;
+	}
+
+	ret = construct_alloc_key(ctx, dest_keyring, flags, user, &key);
+	key_user_put(user);
+
+	if (ret == 0) {
+		ret = construct_key(key, callout_info, callout_len, aux,
+				    dest_keyring);
+		if (ret < 0) {
+			kdebug("cons failed");
+			goto construction_failed;
+		}
+	} else if (ret == -EINPROGRESS) {
+		ret = 0;
+	} else {
+		goto error_put_dest_keyring;
+	}
+
+	key_put(dest_keyring);
+	kleave(" = key %d", key_serial(key));
+	return key;
+
+construction_failed:
+	key_negate_and_link(key, key_negative_timeout, NULL, NULL);
+	key_put(key);
+error_put_dest_keyring:
+	key_put(dest_keyring);
+error:
+	kleave(" = %d", ret);
+	return ERR_PTR(ret);
+}
+
+/**
+ * request_key_and_link - Request a key and cache it in a keyring.
+ * @type: The type of key we want.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ * @dest_keyring: Where to cache the key.
+ * @flags: Flags to key_alloc().
+ *
+ * A key matching the specified criteria is searched for in the process's
+ * keyrings and returned with its usage count incremented if found.  Otherwise,
+ * if callout_info is not NULL, a key will be allocated and some service
+ * (probably in userspace) will be asked to instantiate it.
+ *
+ * If successfully found or created, the key will be linked to the destination
+ * keyring if one is provided.
+ *
+ * Returns a pointer to the key if successful; -EACCES, -ENOKEY, -EKEYREVOKED
+ * or -EKEYEXPIRED if an inaccessible, negative, revoked or expired key was
+ * found; -ENOKEY if no key was found and no @callout_info was given; -EDQUOT
+ * if insufficient key quota was available to create a new key; or -ENOMEM if
+ * insufficient memory was available.
+ *
+ * If the returned key was created, then it may still be under construction,
+ * and wait_for_key_construction() should be used to wait for that to complete.
+ */
+struct key *request_key_and_link(struct key_type *type,
+				 const char *description,
+				 const void *callout_info,
+				 size_t callout_len,
+				 void *aux,
+				 struct key *dest_keyring,
+				 unsigned long flags)
+{
+	struct keyring_search_context ctx = {
+		.index_key.type		= type,
+		.index_key.description	= description,
+		.index_key.desc_len	= strlen(description),
+		.cred			= current_cred(),
+		.match_data.cmp		= key_default_cmp,
+		.match_data.raw_data	= description,
+		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
+		.flags			= (KEYRING_SEARCH_DO_STATE_CHECK |
+					   KEYRING_SEARCH_SKIP_EXPIRED),
+	};
+	struct key *key;
+	key_ref_t key_ref;
+	int ret;
+
+	kenter("%s,%s,%p,%zu,%p,%p,%lx",
+	       ctx.index_key.type->name, ctx.index_key.description,
+	       callout_info, callout_len, aux, dest_keyring, flags);
+
+	if (type->match_preparse) {
+		ret = type->match_preparse(&ctx.match_data);
+		if (ret < 0) {
+			key = ERR_PTR(ret);
+			goto error;
+		}
+	}
+
+	/* search all the process keyrings for a key */
+	key_ref = search_process_keyrings(&ctx);
+
+	if (!IS_ERR(key_ref)) {
+		key = key_ref_to_ptr(key_ref);
+		if (dest_keyring) {
+			ret = key_link(dest_keyring, key);
+			if (ret < 0) {
+				key_put(key);
+				key = ERR_PTR(ret);
+				goto error_free;
+			}
+		}
+	} else if (PTR_ERR(key_ref) != -EAGAIN) {
+		key = ERR_CAST(key_ref);
+	} else  {
+		/* the search failed, but the keyrings were searchable, so we
+		 * should consult userspace if we can */
+		key = ERR_PTR(-ENOKEY);
+		if (!callout_info)
+			goto error_free;
+
+		key = construct_key_and_link(&ctx, callout_info, callout_len,
+					     aux, dest_keyring, flags);
+	}
+
+error_free:
+	if (type->match_free)
+		type->match_free(&ctx.match_data);
+error:
+	kleave(" = %p", key);
+	return key;
+}
+
+/**
+ * wait_for_key_construction - Wait for construction of a key to complete
+ * @key: The key being waited for.
+ * @intr: Whether to wait interruptibly.
+ *
+ * Wait for a key to finish being constructed.
+ *
+ * Returns 0 if successful; -ERESTARTSYS if the wait was interrupted; -ENOKEY
+ * if the key was negated; or -EKEYREVOKED or -EKEYEXPIRED if the key was
+ * revoked or expired.
+ */
+int wait_for_key_construction(struct key *key, bool intr)
+{
+	int ret;
+
+	ret = wait_on_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT,
+			  intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+	if (ret)
+		return -ERESTARTSYS;
+	ret = key_read_state(key);
+	if (ret < 0)
+		return ret;
+	return key_validate(key);
+}
+EXPORT_SYMBOL(wait_for_key_construction);
+
+/**
+ * request_key - Request a key and wait for construction
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found, new keys are always allocated in the user's quota,
+ * the callout_info must be a NUL-terminated string and no auxiliary data can
+ * be passed.
+ *
+ * Furthermore, it then works as wait_for_key_construction() to wait for the
+ * completion of keys undergoing construction with a non-interruptible wait.
+ */
+struct key *request_key(struct key_type *type,
+			const char *description,
+			const char *callout_info)
+{
+	struct key *key;
+	size_t callout_len = 0;
+	int ret;
+
+	if (callout_info)
+		callout_len = strlen(callout_info);
+	key = request_key_and_link(type, description, callout_info, callout_len,
+				   NULL, NULL, KEY_ALLOC_IN_QUOTA);
+	if (!IS_ERR(key)) {
+		ret = wait_for_key_construction(key, false);
+		if (ret < 0) {
+			key_put(key);
+			return ERR_PTR(ret);
+		}
+	}
+	return key;
+}
+EXPORT_SYMBOL(request_key);
+
+/**
+ * request_key_with_auxdata - Request a key with auxiliary data for the upcaller
+ * @type: The type of key we want.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found and new keys are always allocated in the user's quota.
+ *
+ * Furthermore, it then works as wait_for_key_construction() to wait for the
+ * completion of keys undergoing construction with a non-interruptible wait.
+ */
+struct key *request_key_with_auxdata(struct key_type *type,
+				     const char *description,
+				     const void *callout_info,
+				     size_t callout_len,
+				     void *aux)
+{
+	struct key *key;
+	int ret;
+
+	key = request_key_and_link(type, description, callout_info, callout_len,
+				   aux, NULL, KEY_ALLOC_IN_QUOTA);
+	if (!IS_ERR(key)) {
+		ret = wait_for_key_construction(key, false);
+		if (ret < 0) {
+			key_put(key);
+			return ERR_PTR(ret);
+		}
+	}
+	return key;
+}
+EXPORT_SYMBOL(request_key_with_auxdata);
+
+/*
+ * request_key_async - Request a key (allow async construction)
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found, new keys are always allocated in the user's quota and
+ * no auxiliary data can be passed.
+ *
+ * The caller should call wait_for_key_construction() to wait for the
+ * completion of the returned key if it is still undergoing construction.
+ */
+struct key *request_key_async(struct key_type *type,
+			      const char *description,
+			      const void *callout_info,
+			      size_t callout_len)
+{
+	return request_key_and_link(type, description, callout_info,
+				    callout_len, NULL, NULL,
+				    KEY_ALLOC_IN_QUOTA);
+}
+EXPORT_SYMBOL(request_key_async);
+
+/*
+ * request a key with auxiliary data for the upcaller (allow async construction)
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found and new keys are always allocated in the user's quota.
+ *
+ * The caller should call wait_for_key_construction() to wait for the
+ * completion of the returned key if it is still undergoing construction.
+ */
+struct key *request_key_async_with_auxdata(struct key_type *type,
+					   const char *description,
+					   const void *callout_info,
+					   size_t callout_len,
+					   void *aux)
+{
+	return request_key_and_link(type, description, callout_info,
+				    callout_len, aux, NULL, KEY_ALLOC_IN_QUOTA);
+}
+EXPORT_SYMBOL(request_key_async_with_auxdata);
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
new file mode 100644
index 000000000..13ac3b1e5
--- /dev/null
+++ b/security/keys/request_key_auth.c
@@ -0,0 +1,275 @@
+/* Request key authorisation token key definition.
+ *
+ * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * See Documentation/security/keys/request-key.rst
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include "internal.h"
+#include <keys/request_key_auth-type.h>
+
+static int request_key_auth_preparse(struct key_preparsed_payload *);
+static void request_key_auth_free_preparse(struct key_preparsed_payload *);
+static int request_key_auth_instantiate(struct key *,
+					struct key_preparsed_payload *);
+static void request_key_auth_describe(const struct key *, struct seq_file *);
+static void request_key_auth_revoke(struct key *);
+static void request_key_auth_destroy(struct key *);
+static long request_key_auth_read(const struct key *, char *, size_t);
+
+/*
+ * The request-key authorisation key type definition.
+ */
+struct key_type key_type_request_key_auth = {
+	.name		= ".request_key_auth",
+	.def_datalen	= sizeof(struct request_key_auth),
+	.preparse	= request_key_auth_preparse,
+	.free_preparse	= request_key_auth_free_preparse,
+	.instantiate	= request_key_auth_instantiate,
+	.describe	= request_key_auth_describe,
+	.revoke		= request_key_auth_revoke,
+	.destroy	= request_key_auth_destroy,
+	.read		= request_key_auth_read,
+};
+
+static int request_key_auth_preparse(struct key_preparsed_payload *prep)
+{
+	return 0;
+}
+
+static void request_key_auth_free_preparse(struct key_preparsed_payload *prep)
+{
+}
+
+/*
+ * Instantiate a request-key authorisation key.
+ */
+static int request_key_auth_instantiate(struct key *key,
+					struct key_preparsed_payload *prep)
+{
+	key->payload.data[0] = (struct request_key_auth *)prep->data;
+	return 0;
+}
+
+/*
+ * Describe an authorisation token.
+ */
+static void request_key_auth_describe(const struct key *key,
+				      struct seq_file *m)
+{
+	struct request_key_auth *rka = get_request_key_auth(key);
+
+	if (!rka)
+		return;
+
+	seq_puts(m, "key:");
+	seq_puts(m, key->description);
+	if (key_is_positive(key))
+		seq_printf(m, " pid:%d ci:%zu", rka->pid, rka->callout_len);
+}
+
+/*
+ * Read the callout_info data (retrieves the callout information).
+ * - the key's semaphore is read-locked
+ */
+static long request_key_auth_read(const struct key *key,
+				  char *buffer, size_t buflen)
+{
+	struct request_key_auth *rka = get_request_key_auth(key);
+	size_t datalen;
+	long ret;
+
+	if (!rka)
+		return -EKEYREVOKED;
+
+	datalen = rka->callout_len;
+	ret = datalen;
+
+	/* we can return the data as is */
+	if (buffer && buflen > 0) {
+		if (buflen > datalen)
+			buflen = datalen;
+
+		memcpy(buffer, rka->callout_info, buflen);
+	}
+
+	return ret;
+}
+
+/*
+ * Handle revocation of an authorisation token key.
+ *
+ * Called with the key sem write-locked.
+ */
+static void request_key_auth_revoke(struct key *key)
+{
+	struct request_key_auth *rka = get_request_key_auth(key);
+
+	kenter("{%d}", key->serial);
+
+	if (rka->cred) {
+		put_cred(rka->cred);
+		rka->cred = NULL;
+	}
+}
+
+static void free_request_key_auth(struct request_key_auth *rka)
+{
+	if (!rka)
+		return;
+	key_put(rka->target_key);
+	key_put(rka->dest_keyring);
+	if (rka->cred)
+		put_cred(rka->cred);
+	kfree(rka->callout_info);
+	kfree(rka);
+}
+
+/*
+ * Destroy an instantiation authorisation token key.
+ */
+static void request_key_auth_destroy(struct key *key)
+{
+	struct request_key_auth *rka = get_request_key_auth(key);
+
+	kenter("{%d}", key->serial);
+
+	free_request_key_auth(rka);
+}
+
+/*
+ * Create an authorisation token for /sbin/request-key or whoever to gain
+ * access to the caller's security data.
+ */
+struct key *request_key_auth_new(struct key *target, const char *op,
+				 const void *callout_info, size_t callout_len,
+				 struct key *dest_keyring)
+{
+	struct request_key_auth *rka, *irka;
+	const struct cred *cred = current->cred;
+	struct key *authkey = NULL;
+	char desc[20];
+	int ret = -ENOMEM;
+
+	kenter("%d,", target->serial);
+
+	/* allocate a auth record */
+	rka = kzalloc(sizeof(*rka), GFP_KERNEL);
+	if (!rka)
+		goto error;
+	rka->callout_info = kmemdup(callout_info, callout_len, GFP_KERNEL);
+	if (!rka->callout_info)
+		goto error_free_rka;
+	rka->callout_len = callout_len;
+	strlcpy(rka->op, op, sizeof(rka->op));
+
+	/* see if the calling process is already servicing the key request of
+	 * another process */
+	if (cred->request_key_auth) {
+		/* it is - use that instantiation context here too */
+		down_read(&cred->request_key_auth->sem);
+
+		/* if the auth key has been revoked, then the key we're
+		 * servicing is already instantiated */
+		if (test_bit(KEY_FLAG_REVOKED,
+			     &cred->request_key_auth->flags)) {
+			up_read(&cred->request_key_auth->sem);
+			ret = -EKEYREVOKED;
+			goto error_free_rka;
+		}
+
+		irka = cred->request_key_auth->payload.data[0];
+		rka->cred = get_cred(irka->cred);
+		rka->pid = irka->pid;
+
+		up_read(&cred->request_key_auth->sem);
+	}
+	else {
+		/* it isn't - use this process as the context */
+		rka->cred = get_cred(cred);
+		rka->pid = current->pid;
+	}
+
+	rka->target_key = key_get(target);
+	rka->dest_keyring = key_get(dest_keyring);
+
+	/* allocate the auth key */
+	sprintf(desc, "%x", target->serial);
+
+	authkey = key_alloc(&key_type_request_key_auth, desc,
+			    cred->fsuid, cred->fsgid, cred,
+			    KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH |
+			    KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA, NULL);
+	if (IS_ERR(authkey)) {
+		ret = PTR_ERR(authkey);
+		goto error_free_rka;
+	}
+
+	/* construct the auth key */
+	ret = key_instantiate_and_link(authkey, rka, 0, NULL, NULL);
+	if (ret < 0)
+		goto error_put_authkey;
+
+	kleave(" = {%d,%d}", authkey->serial, refcount_read(&authkey->usage));
+	return authkey;
+
+error_put_authkey:
+	key_put(authkey);
+error_free_rka:
+	free_request_key_auth(rka);
+error:
+	kleave("= %d", ret);
+	return ERR_PTR(ret);
+}
+
+/*
+ * Search the current process's keyrings for the authorisation key for
+ * instantiation of a key.
+ */
+struct key *key_get_instantiation_authkey(key_serial_t target_id)
+{
+	char description[16];
+	struct keyring_search_context ctx = {
+		.index_key.type		= &key_type_request_key_auth,
+		.index_key.description	= description,
+		.cred			= current_cred(),
+		.match_data.cmp		= key_default_cmp,
+		.match_data.raw_data	= description,
+		.match_data.lookup_type	= KEYRING_SEARCH_LOOKUP_DIRECT,
+		.flags			= KEYRING_SEARCH_DO_STATE_CHECK,
+	};
+	struct key *authkey;
+	key_ref_t authkey_ref;
+
+	ctx.index_key.desc_len = sprintf(description, "%x", target_id);
+
+	authkey_ref = search_process_keyrings(&ctx);
+
+	if (IS_ERR(authkey_ref)) {
+		authkey = ERR_CAST(authkey_ref);
+		if (authkey == ERR_PTR(-EAGAIN))
+			authkey = ERR_PTR(-ENOKEY);
+		goto error;
+	}
+
+	authkey = key_ref_to_ptr(authkey_ref);
+	if (test_bit(KEY_FLAG_REVOKED, &authkey->flags)) {
+		key_put(authkey);
+		authkey = ERR_PTR(-EKEYREVOKED);
+	}
+
+error:
+	return authkey;
+}
diff --git a/security/keys/sysctl.c b/security/keys/sysctl.c
new file mode 100644
index 000000000..b68faa1a5
--- /dev/null
+++ b/security/keys/sysctl.c
@@ -0,0 +1,76 @@
+/* Key management controls
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/key.h>
+#include <linux/sysctl.h>
+#include "internal.h"
+
+static const int zero, one = 1, max = INT_MAX;
+
+struct ctl_table key_sysctls[] = {
+	{
+		.procname = "maxkeys",
+		.data = &key_quota_maxkeys,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &one,
+		.extra2 = (void *) &max,
+	},
+	{
+		.procname = "maxbytes",
+		.data = &key_quota_maxbytes,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &one,
+		.extra2 = (void *) &max,
+	},
+	{
+		.procname = "root_maxkeys",
+		.data = &key_quota_root_maxkeys,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &one,
+		.extra2 = (void *) &max,
+	},
+	{
+		.procname = "root_maxbytes",
+		.data = &key_quota_root_maxbytes,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &one,
+		.extra2 = (void *) &max,
+	},
+	{
+		.procname = "gc_delay",
+		.data = &key_gc_delay,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &zero,
+		.extra2 = (void *) &max,
+	},
+#ifdef CONFIG_PERSISTENT_KEYRINGS
+	{
+		.procname = "persistent_keyring_expiry",
+		.data = &persistent_keyring_expiry,
+		.maxlen = sizeof(unsigned),
+		.mode = 0644,
+		.proc_handler = proc_dointvec_minmax,
+		.extra1 = (void *) &zero,
+		.extra2 = (void *) &max,
+	},
+#endif
+	{ }
+};
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
new file mode 100644
index 000000000..9179a5bbf
--- /dev/null
+++ b/security/keys/trusted.c
@@ -0,0 +1,1232 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Author:
+ * David Safford <safford@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <crypto/hash_info.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <linux/key-type.h>
+#include <linux/rcupdate.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <linux/capability.h>
+#include <linux/tpm.h>
+#include <linux/tpm_command.h>
+
+#include "trusted.h"
+
+static const char hmac_alg[] = "hmac(sha1)";
+static const char hash_alg[] = "sha1";
+
+struct sdesc {
+	struct shash_desc shash;
+	char ctx[];
+};
+
+static struct crypto_shash *hashalg;
+static struct crypto_shash *hmacalg;
+
+static struct sdesc *init_sdesc(struct crypto_shash *alg)
+{
+	struct sdesc *sdesc;
+	int size;
+
+	size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
+	sdesc = kmalloc(size, GFP_KERNEL);
+	if (!sdesc)
+		return ERR_PTR(-ENOMEM);
+	sdesc->shash.tfm = alg;
+	sdesc->shash.flags = 0x0;
+	return sdesc;
+}
+
+static int TSS_sha1(const unsigned char *data, unsigned int datalen,
+		    unsigned char *digest)
+{
+	struct sdesc *sdesc;
+	int ret;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
+	kzfree(sdesc);
+	return ret;
+}
+
+static int TSS_rawhmac(unsigned char *digest, const unsigned char *key,
+		       unsigned int keylen, ...)
+{
+	struct sdesc *sdesc;
+	va_list argp;
+	unsigned int dlen;
+	unsigned char *data;
+	int ret;
+
+	sdesc = init_sdesc(hmacalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hmac_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	ret = crypto_shash_setkey(hmacalg, key, keylen);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+
+	va_start(argp, keylen);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		data = va_arg(argp, unsigned char *);
+		if (data == NULL) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = crypto_shash_update(&sdesc->shash, data, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, digest);
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * calculate authorization info fields to send to TPM
+ */
+static int TSS_authhmac(unsigned char *digest, const unsigned char *key,
+			unsigned int keylen, unsigned char *h1,
+			unsigned char *h2, unsigned char h3, ...)
+{
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned char *data;
+	unsigned char c;
+	int ret;
+	va_list argp;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	c = h3;
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	va_start(argp, h3);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		data = va_arg(argp, unsigned char *);
+		if (!data) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = crypto_shash_update(&sdesc->shash, data, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (!ret)
+		ret = TSS_rawhmac(digest, key, keylen, SHA1_DIGEST_SIZE,
+				  paramdigest, TPM_NONCE_SIZE, h1,
+				  TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * verify the AUTH1_COMMAND (Seal) result from TPM
+ */
+static int TSS_checkhmac1(unsigned char *buffer,
+			  const uint32_t command,
+			  const unsigned char *ononce,
+			  const unsigned char *key,
+			  unsigned int keylen, ...)
+{
+	uint32_t bufsize;
+	uint16_t tag;
+	uint32_t ordinal;
+	uint32_t result;
+	unsigned char *enonce;
+	unsigned char *continueflag;
+	unsigned char *authdata;
+	unsigned char testhmac[SHA1_DIGEST_SIZE];
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned int dpos;
+	va_list argp;
+	int ret;
+
+	bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+	tag = LOAD16(buffer, 0);
+	ordinal = command;
+	result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+	if (tag == TPM_TAG_RSP_COMMAND)
+		return 0;
+	if (tag != TPM_TAG_RSP_AUTH1_COMMAND)
+		return -EINVAL;
+	authdata = buffer + bufsize - SHA1_DIGEST_SIZE;
+	continueflag = authdata - 1;
+	enonce = continueflag - TPM_NONCE_SIZE;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+				  sizeof result);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+				  sizeof ordinal);
+	if (ret < 0)
+		goto out;
+	va_start(argp, keylen);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		dpos = va_arg(argp, unsigned int);
+		ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (ret < 0)
+		goto out;
+
+	ret = TSS_rawhmac(testhmac, key, keylen, SHA1_DIGEST_SIZE, paramdigest,
+			  TPM_NONCE_SIZE, enonce, TPM_NONCE_SIZE, ononce,
+			  1, continueflag, 0, 0);
+	if (ret < 0)
+		goto out;
+
+	if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
+		ret = -EINVAL;
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * verify the AUTH2_COMMAND (unseal) result from TPM
+ */
+static int TSS_checkhmac2(unsigned char *buffer,
+			  const uint32_t command,
+			  const unsigned char *ononce,
+			  const unsigned char *key1,
+			  unsigned int keylen1,
+			  const unsigned char *key2,
+			  unsigned int keylen2, ...)
+{
+	uint32_t bufsize;
+	uint16_t tag;
+	uint32_t ordinal;
+	uint32_t result;
+	unsigned char *enonce1;
+	unsigned char *continueflag1;
+	unsigned char *authdata1;
+	unsigned char *enonce2;
+	unsigned char *continueflag2;
+	unsigned char *authdata2;
+	unsigned char testhmac1[SHA1_DIGEST_SIZE];
+	unsigned char testhmac2[SHA1_DIGEST_SIZE];
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned int dpos;
+	va_list argp;
+	int ret;
+
+	bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+	tag = LOAD16(buffer, 0);
+	ordinal = command;
+	result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+
+	if (tag == TPM_TAG_RSP_COMMAND)
+		return 0;
+	if (tag != TPM_TAG_RSP_AUTH2_COMMAND)
+		return -EINVAL;
+	authdata1 = buffer + bufsize - (SHA1_DIGEST_SIZE + 1
+			+ SHA1_DIGEST_SIZE + SHA1_DIGEST_SIZE);
+	authdata2 = buffer + bufsize - (SHA1_DIGEST_SIZE);
+	continueflag1 = authdata1 - 1;
+	continueflag2 = authdata2 - 1;
+	enonce1 = continueflag1 - TPM_NONCE_SIZE;
+	enonce2 = continueflag2 - TPM_NONCE_SIZE;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+				  sizeof result);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+				  sizeof ordinal);
+	if (ret < 0)
+		goto out;
+
+	va_start(argp, keylen2);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		dpos = va_arg(argp, unsigned int);
+		ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (ret < 0)
+		goto out;
+
+	ret = TSS_rawhmac(testhmac1, key1, keylen1, SHA1_DIGEST_SIZE,
+			  paramdigest, TPM_NONCE_SIZE, enonce1,
+			  TPM_NONCE_SIZE, ononce, 1, continueflag1, 0, 0);
+	if (ret < 0)
+		goto out;
+	if (memcmp(testhmac1, authdata1, SHA1_DIGEST_SIZE)) {
+		ret = -EINVAL;
+		goto out;
+	}
+	ret = TSS_rawhmac(testhmac2, key2, keylen2, SHA1_DIGEST_SIZE,
+			  paramdigest, TPM_NONCE_SIZE, enonce2,
+			  TPM_NONCE_SIZE, ononce, 1, continueflag2, 0, 0);
+	if (ret < 0)
+		goto out;
+	if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
+		ret = -EINVAL;
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * For key specific tpm requests, we will generate and send our
+ * own TPM command packets using the drivers send function.
+ */
+static int trusted_tpm_send(unsigned char *cmd, size_t buflen)
+{
+	int rc;
+
+	dump_tpm_buf(cmd);
+	rc = tpm_send(NULL, cmd, buflen);
+	dump_tpm_buf(cmd);
+	if (rc > 0)
+		/* Can't return positive return codes values to keyctl */
+		rc = -EPERM;
+	return rc;
+}
+
+/*
+ * Lock a trusted key, by extending a selected PCR.
+ *
+ * Prevents a trusted key that is sealed to PCRs from being accessed.
+ * This uses the tpm driver's extend function.
+ */
+static int pcrlock(const int pcrnum)
+{
+	unsigned char hash[SHA1_DIGEST_SIZE];
+	int ret;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	ret = tpm_get_random(NULL, hash, SHA1_DIGEST_SIZE);
+	if (ret != SHA1_DIGEST_SIZE)
+		return ret;
+	return tpm_pcr_extend(NULL, pcrnum, hash) ? -EINVAL : 0;
+}
+
+/*
+ * Create an object specific authorisation protocol (OSAP) session
+ */
+static int osap(struct tpm_buf *tb, struct osapsess *s,
+		const unsigned char *key, uint16_t type, uint32_t handle)
+{
+	unsigned char enonce[TPM_NONCE_SIZE];
+	unsigned char ononce[TPM_NONCE_SIZE];
+	int ret;
+
+	ret = tpm_get_random(NULL, ononce, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE)
+		return ret;
+
+	INIT_BUF(tb);
+	store16(tb, TPM_TAG_RQU_COMMAND);
+	store32(tb, TPM_OSAP_SIZE);
+	store32(tb, TPM_ORD_OSAP);
+	store16(tb, type);
+	store32(tb, handle);
+	storebytes(tb, ononce, TPM_NONCE_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		return ret;
+
+	s->handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+	memcpy(s->enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)]),
+	       TPM_NONCE_SIZE);
+	memcpy(enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t) +
+				  TPM_NONCE_SIZE]), TPM_NONCE_SIZE);
+	return TSS_rawhmac(s->secret, key, SHA1_DIGEST_SIZE, TPM_NONCE_SIZE,
+			   enonce, TPM_NONCE_SIZE, ononce, 0, 0);
+}
+
+/*
+ * Create an object independent authorisation protocol (oiap) session
+ */
+static int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
+{
+	int ret;
+
+	INIT_BUF(tb);
+	store16(tb, TPM_TAG_RQU_COMMAND);
+	store32(tb, TPM_OIAP_SIZE);
+	store32(tb, TPM_ORD_OIAP);
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		return ret;
+
+	*handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+	memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
+	       TPM_NONCE_SIZE);
+	return 0;
+}
+
+struct tpm_digests {
+	unsigned char encauth[SHA1_DIGEST_SIZE];
+	unsigned char pubauth[SHA1_DIGEST_SIZE];
+	unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
+	unsigned char xorhash[SHA1_DIGEST_SIZE];
+	unsigned char nonceodd[TPM_NONCE_SIZE];
+};
+
+/*
+ * Have the TPM seal(encrypt) the trusted key, possibly based on
+ * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
+ */
+static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
+		    uint32_t keyhandle, const unsigned char *keyauth,
+		    const unsigned char *data, uint32_t datalen,
+		    unsigned char *blob, uint32_t *bloblen,
+		    const unsigned char *blobauth,
+		    const unsigned char *pcrinfo, uint32_t pcrinfosize)
+{
+	struct osapsess sess;
+	struct tpm_digests *td;
+	unsigned char cont;
+	uint32_t ordinal;
+	uint32_t pcrsize;
+	uint32_t datsize;
+	int sealinfosize;
+	int encdatasize;
+	int storedsize;
+	int ret;
+	int i;
+
+	/* alloc some work space for all the hashes */
+	td = kmalloc(sizeof *td, GFP_KERNEL);
+	if (!td)
+		return -ENOMEM;
+
+	/* get session for sealing key */
+	ret = osap(tb, &sess, keyauth, keytype, keyhandle);
+	if (ret < 0)
+		goto out;
+	dump_sess(&sess);
+
+	/* calculate encrypted authorization value */
+	memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
+	memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
+	ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
+	if (ret < 0)
+		goto out;
+
+	ret = tpm_get_random(NULL, td->nonceodd, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE)
+		goto out;
+	ordinal = htonl(TPM_ORD_SEAL);
+	datsize = htonl(datalen);
+	pcrsize = htonl(pcrinfosize);
+	cont = 0;
+
+	/* encrypt data authorization key */
+	for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
+		td->encauth[i] = td->xorhash[i] ^ blobauth[i];
+
+	/* calculate authorization HMAC value */
+	if (pcrinfosize == 0) {
+		/* no pcr info specified */
+		ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+				   sess.enonce, td->nonceodd, cont,
+				   sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+				   td->encauth, sizeof(uint32_t), &pcrsize,
+				   sizeof(uint32_t), &datsize, datalen, data, 0,
+				   0);
+	} else {
+		/* pcr info specified */
+		ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+				   sess.enonce, td->nonceodd, cont,
+				   sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+				   td->encauth, sizeof(uint32_t), &pcrsize,
+				   pcrinfosize, pcrinfo, sizeof(uint32_t),
+				   &datsize, datalen, data, 0, 0);
+	}
+	if (ret < 0)
+		goto out;
+
+	/* build and send the TPM request packet */
+	INIT_BUF(tb);
+	store16(tb, TPM_TAG_RQU_AUTH1_COMMAND);
+	store32(tb, TPM_SEAL_SIZE + pcrinfosize + datalen);
+	store32(tb, TPM_ORD_SEAL);
+	store32(tb, keyhandle);
+	storebytes(tb, td->encauth, SHA1_DIGEST_SIZE);
+	store32(tb, pcrinfosize);
+	storebytes(tb, pcrinfo, pcrinfosize);
+	store32(tb, datalen);
+	storebytes(tb, data, datalen);
+	store32(tb, sess.handle);
+	storebytes(tb, td->nonceodd, TPM_NONCE_SIZE);
+	store8(tb, cont);
+	storebytes(tb, td->pubauth, SHA1_DIGEST_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		goto out;
+
+	/* calculate the size of the returned Blob */
+	sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
+	encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
+			     sizeof(uint32_t) + sealinfosize);
+	storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
+	    sizeof(uint32_t) + encdatasize;
+
+	/* check the HMAC in the response */
+	ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
+			     SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
+			     0);
+
+	/* copy the returned blob to caller */
+	if (!ret) {
+		memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
+		*bloblen = storedsize;
+	}
+out:
+	kzfree(td);
+	return ret;
+}
+
+/*
+ * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
+ */
+static int tpm_unseal(struct tpm_buf *tb,
+		      uint32_t keyhandle, const unsigned char *keyauth,
+		      const unsigned char *blob, int bloblen,
+		      const unsigned char *blobauth,
+		      unsigned char *data, unsigned int *datalen)
+{
+	unsigned char nonceodd[TPM_NONCE_SIZE];
+	unsigned char enonce1[TPM_NONCE_SIZE];
+	unsigned char enonce2[TPM_NONCE_SIZE];
+	unsigned char authdata1[SHA1_DIGEST_SIZE];
+	unsigned char authdata2[SHA1_DIGEST_SIZE];
+	uint32_t authhandle1 = 0;
+	uint32_t authhandle2 = 0;
+	unsigned char cont = 0;
+	uint32_t ordinal;
+	uint32_t keyhndl;
+	int ret;
+
+	/* sessions for unsealing key and data */
+	ret = oiap(tb, &authhandle1, enonce1);
+	if (ret < 0) {
+		pr_info("trusted_key: oiap failed (%d)\n", ret);
+		return ret;
+	}
+	ret = oiap(tb, &authhandle2, enonce2);
+	if (ret < 0) {
+		pr_info("trusted_key: oiap failed (%d)\n", ret);
+		return ret;
+	}
+
+	ordinal = htonl(TPM_ORD_UNSEAL);
+	keyhndl = htonl(SRKHANDLE);
+	ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE) {
+		pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
+		return ret;
+	}
+	ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
+			   enonce1, nonceodd, cont, sizeof(uint32_t),
+			   &ordinal, bloblen, blob, 0, 0);
+	if (ret < 0)
+		return ret;
+	ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
+			   enonce2, nonceodd, cont, sizeof(uint32_t),
+			   &ordinal, bloblen, blob, 0, 0);
+	if (ret < 0)
+		return ret;
+
+	/* build and send TPM request packet */
+	INIT_BUF(tb);
+	store16(tb, TPM_TAG_RQU_AUTH2_COMMAND);
+	store32(tb, TPM_UNSEAL_SIZE + bloblen);
+	store32(tb, TPM_ORD_UNSEAL);
+	store32(tb, keyhandle);
+	storebytes(tb, blob, bloblen);
+	store32(tb, authhandle1);
+	storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+	store8(tb, cont);
+	storebytes(tb, authdata1, SHA1_DIGEST_SIZE);
+	store32(tb, authhandle2);
+	storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+	store8(tb, cont);
+	storebytes(tb, authdata2, SHA1_DIGEST_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0) {
+		pr_info("trusted_key: authhmac failed (%d)\n", ret);
+		return ret;
+	}
+
+	*datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
+	ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
+			     keyauth, SHA1_DIGEST_SIZE,
+			     blobauth, SHA1_DIGEST_SIZE,
+			     sizeof(uint32_t), TPM_DATA_OFFSET,
+			     *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
+			     0);
+	if (ret < 0) {
+		pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
+		return ret;
+	}
+	memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
+	return 0;
+}
+
+/*
+ * Have the TPM seal(encrypt) the symmetric key
+ */
+static int key_seal(struct trusted_key_payload *p,
+		    struct trusted_key_options *o)
+{
+	struct tpm_buf *tb;
+	int ret;
+
+	tb = kzalloc(sizeof *tb, GFP_KERNEL);
+	if (!tb)
+		return -ENOMEM;
+
+	/* include migratable flag at end of sealed key */
+	p->key[p->key_len] = p->migratable;
+
+	ret = tpm_seal(tb, o->keytype, o->keyhandle, o->keyauth,
+		       p->key, p->key_len + 1, p->blob, &p->blob_len,
+		       o->blobauth, o->pcrinfo, o->pcrinfo_len);
+	if (ret < 0)
+		pr_info("trusted_key: srkseal failed (%d)\n", ret);
+
+	kzfree(tb);
+	return ret;
+}
+
+/*
+ * Have the TPM unseal(decrypt) the symmetric key
+ */
+static int key_unseal(struct trusted_key_payload *p,
+		      struct trusted_key_options *o)
+{
+	struct tpm_buf *tb;
+	int ret;
+
+	tb = kzalloc(sizeof *tb, GFP_KERNEL);
+	if (!tb)
+		return -ENOMEM;
+
+	ret = tpm_unseal(tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
+			 o->blobauth, p->key, &p->key_len);
+	if (ret < 0)
+		pr_info("trusted_key: srkunseal failed (%d)\n", ret);
+	else
+		/* pull migratable flag out of sealed key */
+		p->migratable = p->key[--p->key_len];
+
+	kzfree(tb);
+	return ret;
+}
+
+enum {
+	Opt_err = -1,
+	Opt_new, Opt_load, Opt_update,
+	Opt_keyhandle, Opt_keyauth, Opt_blobauth,
+	Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
+	Opt_hash,
+	Opt_policydigest,
+	Opt_policyhandle,
+};
+
+static const match_table_t key_tokens = {
+	{Opt_new, "new"},
+	{Opt_load, "load"},
+	{Opt_update, "update"},
+	{Opt_keyhandle, "keyhandle=%s"},
+	{Opt_keyauth, "keyauth=%s"},
+	{Opt_blobauth, "blobauth=%s"},
+	{Opt_pcrinfo, "pcrinfo=%s"},
+	{Opt_pcrlock, "pcrlock=%s"},
+	{Opt_migratable, "migratable=%s"},
+	{Opt_hash, "hash=%s"},
+	{Opt_policydigest, "policydigest=%s"},
+	{Opt_policyhandle, "policyhandle=%s"},
+	{Opt_err, NULL}
+};
+
+/* can have zero or more token= options */
+static int getoptions(char *c, struct trusted_key_payload *pay,
+		      struct trusted_key_options *opt)
+{
+	substring_t args[MAX_OPT_ARGS];
+	char *p = c;
+	int token;
+	int res;
+	unsigned long handle;
+	unsigned long lock;
+	unsigned long token_mask = 0;
+	unsigned int digest_len;
+	int i;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(NULL);
+	if (tpm2 < 0)
+		return tpm2;
+
+	opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
+
+	while ((p = strsep(&c, " \t"))) {
+		if (*p == '\0' || *p == ' ' || *p == '\t')
+			continue;
+		token = match_token(p, key_tokens, args);
+		if (test_and_set_bit(token, &token_mask))
+			return -EINVAL;
+
+		switch (token) {
+		case Opt_pcrinfo:
+			opt->pcrinfo_len = strlen(args[0].from) / 2;
+			if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->pcrinfo, args[0].from,
+				      opt->pcrinfo_len);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_keyhandle:
+			res = kstrtoul(args[0].from, 16, &handle);
+			if (res < 0)
+				return -EINVAL;
+			opt->keytype = SEAL_keytype;
+			opt->keyhandle = handle;
+			break;
+		case Opt_keyauth:
+			if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->keyauth, args[0].from,
+				      SHA1_DIGEST_SIZE);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_blobauth:
+			if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->blobauth, args[0].from,
+				      SHA1_DIGEST_SIZE);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_migratable:
+			if (*args[0].from == '0')
+				pay->migratable = 0;
+			else if (*args[0].from != '1')
+				return -EINVAL;
+			break;
+		case Opt_pcrlock:
+			res = kstrtoul(args[0].from, 10, &lock);
+			if (res < 0)
+				return -EINVAL;
+			opt->pcrlock = lock;
+			break;
+		case Opt_hash:
+			if (test_bit(Opt_policydigest, &token_mask))
+				return -EINVAL;
+			for (i = 0; i < HASH_ALGO__LAST; i++) {
+				if (!strcmp(args[0].from, hash_algo_name[i])) {
+					opt->hash = i;
+					break;
+				}
+			}
+			if (i == HASH_ALGO__LAST)
+				return -EINVAL;
+			if  (!tpm2 && i != HASH_ALGO_SHA1) {
+				pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
+				return -EINVAL;
+			}
+			break;
+		case Opt_policydigest:
+			digest_len = hash_digest_size[opt->hash];
+			if (!tpm2 || strlen(args[0].from) != (2 * digest_len))
+				return -EINVAL;
+			res = hex2bin(opt->policydigest, args[0].from,
+				      digest_len);
+			if (res < 0)
+				return -EINVAL;
+			opt->policydigest_len = digest_len;
+			break;
+		case Opt_policyhandle:
+			if (!tpm2)
+				return -EINVAL;
+			res = kstrtoul(args[0].from, 16, &handle);
+			if (res < 0)
+				return -EINVAL;
+			opt->policyhandle = handle;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+/*
+ * datablob_parse - parse the keyctl data and fill in the
+ * 		    payload and options structures
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, struct trusted_key_payload *p,
+			  struct trusted_key_options *o)
+{
+	substring_t args[MAX_OPT_ARGS];
+	long keylen;
+	int ret = -EINVAL;
+	int key_cmd;
+	char *c;
+
+	/* main command */
+	c = strsep(&datablob, " \t");
+	if (!c)
+		return -EINVAL;
+	key_cmd = match_token(c, key_tokens, args);
+	switch (key_cmd) {
+	case Opt_new:
+		/* first argument is key size */
+		c = strsep(&datablob, " \t");
+		if (!c)
+			return -EINVAL;
+		ret = kstrtol(c, 10, &keylen);
+		if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
+			return -EINVAL;
+		p->key_len = keylen;
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_new;
+		break;
+	case Opt_load:
+		/* first argument is sealed blob */
+		c = strsep(&datablob, " \t");
+		if (!c)
+			return -EINVAL;
+		p->blob_len = strlen(c) / 2;
+		if (p->blob_len > MAX_BLOB_SIZE)
+			return -EINVAL;
+		ret = hex2bin(p->blob, c, p->blob_len);
+		if (ret < 0)
+			return -EINVAL;
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_load;
+		break;
+	case Opt_update:
+		/* all arguments are options */
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_update;
+		break;
+	case Opt_err:
+		return -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static struct trusted_key_options *trusted_options_alloc(void)
+{
+	struct trusted_key_options *options;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(NULL);
+	if (tpm2 < 0)
+		return NULL;
+
+	options = kzalloc(sizeof *options, GFP_KERNEL);
+	if (options) {
+		/* set any non-zero defaults */
+		options->keytype = SRK_keytype;
+
+		if (!tpm2)
+			options->keyhandle = SRKHANDLE;
+	}
+	return options;
+}
+
+static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
+{
+	struct trusted_key_payload *p = NULL;
+	int ret;
+
+	ret = key_payload_reserve(key, sizeof *p);
+	if (ret < 0)
+		return p;
+	p = kzalloc(sizeof *p, GFP_KERNEL);
+	if (p)
+		p->migratable = 1; /* migratable by default */
+	return p;
+}
+
+/*
+ * trusted_instantiate - create a new trusted key
+ *
+ * Unseal an existing trusted blob or, for a new key, get a
+ * random key, then seal and create a trusted key-type key,
+ * adding it to the specified keyring.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int trusted_instantiate(struct key *key,
+			       struct key_preparsed_payload *prep)
+{
+	struct trusted_key_payload *payload = NULL;
+	struct trusted_key_options *options = NULL;
+	size_t datalen = prep->datalen;
+	char *datablob;
+	int ret = 0;
+	int key_cmd;
+	size_t key_len;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(NULL);
+	if (tpm2 < 0)
+		return tpm2;
+
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	datablob = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!datablob)
+		return -ENOMEM;
+	memcpy(datablob, prep->data, datalen);
+	datablob[datalen] = '\0';
+
+	options = trusted_options_alloc();
+	if (!options) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	payload = trusted_payload_alloc(key);
+	if (!payload) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	key_cmd = datablob_parse(datablob, payload, options);
+	if (key_cmd < 0) {
+		ret = key_cmd;
+		goto out;
+	}
+
+	if (!options->keyhandle) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	dump_payload(payload);
+	dump_options(options);
+
+	switch (key_cmd) {
+	case Opt_load:
+		if (tpm2)
+			ret = tpm_unseal_trusted(NULL, payload, options);
+		else
+			ret = key_unseal(payload, options);
+		dump_payload(payload);
+		dump_options(options);
+		if (ret < 0)
+			pr_info("trusted_key: key_unseal failed (%d)\n", ret);
+		break;
+	case Opt_new:
+		key_len = payload->key_len;
+		ret = tpm_get_random(NULL, payload->key, key_len);
+		if (ret != key_len) {
+			pr_info("trusted_key: key_create failed (%d)\n", ret);
+			goto out;
+		}
+		if (tpm2)
+			ret = tpm_seal_trusted(NULL, payload, options);
+		else
+			ret = key_seal(payload, options);
+		if (ret < 0)
+			pr_info("trusted_key: key_seal failed (%d)\n", ret);
+		break;
+	default:
+		ret = -EINVAL;
+		goto out;
+	}
+	if (!ret && options->pcrlock)
+		ret = pcrlock(options->pcrlock);
+out:
+	kzfree(datablob);
+	kzfree(options);
+	if (!ret)
+		rcu_assign_keypointer(key, payload);
+	else
+		kzfree(payload);
+	return ret;
+}
+
+static void trusted_rcu_free(struct rcu_head *rcu)
+{
+	struct trusted_key_payload *p;
+
+	p = container_of(rcu, struct trusted_key_payload, rcu);
+	kzfree(p);
+}
+
+/*
+ * trusted_update - reseal an existing key with new PCR values
+ */
+static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
+{
+	struct trusted_key_payload *p;
+	struct trusted_key_payload *new_p;
+	struct trusted_key_options *new_o;
+	size_t datalen = prep->datalen;
+	char *datablob;
+	int ret = 0;
+
+	if (key_is_negative(key))
+		return -ENOKEY;
+	p = key->payload.data[0];
+	if (!p->migratable)
+		return -EPERM;
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	datablob = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!datablob)
+		return -ENOMEM;
+	new_o = trusted_options_alloc();
+	if (!new_o) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	new_p = trusted_payload_alloc(key);
+	if (!new_p) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	memcpy(datablob, prep->data, datalen);
+	datablob[datalen] = '\0';
+	ret = datablob_parse(datablob, new_p, new_o);
+	if (ret != Opt_update) {
+		ret = -EINVAL;
+		kzfree(new_p);
+		goto out;
+	}
+
+	if (!new_o->keyhandle) {
+		ret = -EINVAL;
+		kzfree(new_p);
+		goto out;
+	}
+
+	/* copy old key values, and reseal with new pcrs */
+	new_p->migratable = p->migratable;
+	new_p->key_len = p->key_len;
+	memcpy(new_p->key, p->key, p->key_len);
+	dump_payload(p);
+	dump_payload(new_p);
+
+	ret = key_seal(new_p, new_o);
+	if (ret < 0) {
+		pr_info("trusted_key: key_seal failed (%d)\n", ret);
+		kzfree(new_p);
+		goto out;
+	}
+	if (new_o->pcrlock) {
+		ret = pcrlock(new_o->pcrlock);
+		if (ret < 0) {
+			pr_info("trusted_key: pcrlock failed (%d)\n", ret);
+			kzfree(new_p);
+			goto out;
+		}
+	}
+	rcu_assign_keypointer(key, new_p);
+	call_rcu(&p->rcu, trusted_rcu_free);
+out:
+	kzfree(datablob);
+	kzfree(new_o);
+	return ret;
+}
+
+/*
+ * trusted_read - copy the sealed blob data to userspace in hex.
+ * On success, return to userspace the trusted key datablob size.
+ */
+static long trusted_read(const struct key *key, char *buffer,
+			 size_t buflen)
+{
+	const struct trusted_key_payload *p;
+	char *bufp;
+	int i;
+
+	p = dereference_key_locked(key);
+	if (!p)
+		return -EINVAL;
+
+	if (buffer && buflen >= 2 * p->blob_len) {
+		bufp = buffer;
+		for (i = 0; i < p->blob_len; i++)
+			bufp = hex_byte_pack(bufp, p->blob[i]);
+	}
+	return 2 * p->blob_len;
+}
+
+/*
+ * trusted_destroy - clear and free the key's payload
+ */
+static void trusted_destroy(struct key *key)
+{
+	kzfree(key->payload.data[0]);
+}
+
+struct key_type key_type_trusted = {
+	.name = "trusted",
+	.instantiate = trusted_instantiate,
+	.update = trusted_update,
+	.destroy = trusted_destroy,
+	.describe = user_describe,
+	.read = trusted_read,
+};
+
+EXPORT_SYMBOL_GPL(key_type_trusted);
+
+static void trusted_shash_release(void)
+{
+	if (hashalg)
+		crypto_free_shash(hashalg);
+	if (hmacalg)
+		crypto_free_shash(hmacalg);
+}
+
+static int __init trusted_shash_alloc(void)
+{
+	int ret;
+
+	hmacalg = crypto_alloc_shash(hmac_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(hmacalg)) {
+		pr_info("trusted_key: could not allocate crypto %s\n",
+			hmac_alg);
+		return PTR_ERR(hmacalg);
+	}
+
+	hashalg = crypto_alloc_shash(hash_alg, 0, CRYPTO_ALG_ASYNC);
+	if (IS_ERR(hashalg)) {
+		pr_info("trusted_key: could not allocate crypto %s\n",
+			hash_alg);
+		ret = PTR_ERR(hashalg);
+		goto hashalg_fail;
+	}
+
+	return 0;
+
+hashalg_fail:
+	crypto_free_shash(hmacalg);
+	return ret;
+}
+
+static int __init init_trusted(void)
+{
+	int ret;
+
+	ret = trusted_shash_alloc();
+	if (ret < 0)
+		return ret;
+	ret = register_key_type(&key_type_trusted);
+	if (ret < 0)
+		trusted_shash_release();
+	return ret;
+}
+
+static void __exit cleanup_trusted(void)
+{
+	trusted_shash_release();
+	unregister_key_type(&key_type_trusted);
+}
+
+late_initcall(init_trusted);
+module_exit(cleanup_trusted);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/trusted.h b/security/keys/trusted.h
new file mode 100644
index 000000000..8d5fe9eaf
--- /dev/null
+++ b/security/keys/trusted.h
@@ -0,0 +1,124 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __TRUSTED_KEY_H
+#define __TRUSTED_KEY_H
+
+/* implementation specific TPM constants */
+#define MAX_BUF_SIZE			512
+#define TPM_GETRANDOM_SIZE		14
+#define TPM_OSAP_SIZE			36
+#define TPM_OIAP_SIZE			10
+#define TPM_SEAL_SIZE			87
+#define TPM_UNSEAL_SIZE			104
+#define TPM_SIZE_OFFSET			2
+#define TPM_RETURN_OFFSET		6
+#define TPM_DATA_OFFSET			10
+
+#define LOAD32(buffer, offset)	(ntohl(*(uint32_t *)&buffer[offset]))
+#define LOAD32N(buffer, offset)	(*(uint32_t *)&buffer[offset])
+#define LOAD16(buffer, offset)	(ntohs(*(uint16_t *)&buffer[offset]))
+
+struct tpm_buf {
+	int len;
+	unsigned char data[MAX_BUF_SIZE];
+};
+
+#define INIT_BUF(tb) (tb->len = 0)
+
+struct osapsess {
+	uint32_t handle;
+	unsigned char secret[SHA1_DIGEST_SIZE];
+	unsigned char enonce[TPM_NONCE_SIZE];
+};
+
+/* discrete values, but have to store in uint16_t for TPM use */
+enum {
+	SEAL_keytype = 1,
+	SRK_keytype = 4
+};
+
+#define TPM_DEBUG 0
+
+#if TPM_DEBUG
+static inline void dump_options(struct trusted_key_options *o)
+{
+	pr_info("trusted_key: sealing key type %d\n", o->keytype);
+	pr_info("trusted_key: sealing key handle %0X\n", o->keyhandle);
+	pr_info("trusted_key: pcrlock %d\n", o->pcrlock);
+	pr_info("trusted_key: pcrinfo %d\n", o->pcrinfo_len);
+	print_hex_dump(KERN_INFO, "pcrinfo ", DUMP_PREFIX_NONE,
+		       16, 1, o->pcrinfo, o->pcrinfo_len, 0);
+}
+
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+	pr_info("trusted_key: key_len %d\n", p->key_len);
+	print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
+		       16, 1, p->key, p->key_len, 0);
+	pr_info("trusted_key: bloblen %d\n", p->blob_len);
+	print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
+		       16, 1, p->blob, p->blob_len, 0);
+	pr_info("trusted_key: migratable %d\n", p->migratable);
+}
+
+static inline void dump_sess(struct osapsess *s)
+{
+	print_hex_dump(KERN_INFO, "trusted-key: handle ", DUMP_PREFIX_NONE,
+		       16, 1, &s->handle, 4, 0);
+	pr_info("trusted-key: secret:\n");
+	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE,
+		       16, 1, &s->secret, SHA1_DIGEST_SIZE, 0);
+	pr_info("trusted-key: enonce:\n");
+	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE,
+		       16, 1, &s->enonce, SHA1_DIGEST_SIZE, 0);
+}
+
+static inline void dump_tpm_buf(unsigned char *buf)
+{
+	int len;
+
+	pr_info("\ntrusted-key: tpm buffer\n");
+	len = LOAD32(buf, TPM_SIZE_OFFSET);
+	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1, buf, len, 0);
+}
+#else
+static inline void dump_options(struct trusted_key_options *o)
+{
+}
+
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+}
+
+static inline void dump_sess(struct osapsess *s)
+{
+}
+
+static inline void dump_tpm_buf(unsigned char *buf)
+{
+}
+#endif
+
+static inline void store8(struct tpm_buf *buf, const unsigned char value)
+{
+	buf->data[buf->len++] = value;
+}
+
+static inline void store16(struct tpm_buf *buf, const uint16_t value)
+{
+	*(uint16_t *) & buf->data[buf->len] = htons(value);
+	buf->len += sizeof value;
+}
+
+static inline void store32(struct tpm_buf *buf, const uint32_t value)
+{
+	*(uint32_t *) & buf->data[buf->len] = htonl(value);
+	buf->len += sizeof value;
+}
+
+static inline void storebytes(struct tpm_buf *buf, const unsigned char *in,
+			      const int len)
+{
+	memcpy(buf->data + buf->len, in, len);
+	buf->len += len;
+}
+#endif
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
new file mode 100644
index 000000000..0e723b676
--- /dev/null
+++ b/security/keys/user_defined.c
@@ -0,0 +1,211 @@
+/* user_defined.c: user defined key type
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <linux/uaccess.h>
+#include "internal.h"
+
+static int logon_vet_description(const char *desc);
+
+/*
+ * user defined keys take an arbitrary string as the description and an
+ * arbitrary blob of data as the payload
+ */
+struct key_type key_type_user = {
+	.name			= "user",
+	.preparse		= user_preparse,
+	.free_preparse		= user_free_preparse,
+	.instantiate		= generic_key_instantiate,
+	.update			= user_update,
+	.revoke			= user_revoke,
+	.destroy		= user_destroy,
+	.describe		= user_describe,
+	.read			= user_read,
+};
+
+EXPORT_SYMBOL_GPL(key_type_user);
+
+/*
+ * This key type is essentially the same as key_type_user, but it does
+ * not define a .read op. This is suitable for storing username and
+ * password pairs in the keyring that you do not want to be readable
+ * from userspace.
+ */
+struct key_type key_type_logon = {
+	.name			= "logon",
+	.preparse		= user_preparse,
+	.free_preparse		= user_free_preparse,
+	.instantiate		= generic_key_instantiate,
+	.update			= user_update,
+	.revoke			= user_revoke,
+	.destroy		= user_destroy,
+	.describe		= user_describe,
+	.vet_description	= logon_vet_description,
+};
+EXPORT_SYMBOL_GPL(key_type_logon);
+
+/*
+ * Preparse a user defined key payload
+ */
+int user_preparse(struct key_preparsed_payload *prep)
+{
+	struct user_key_payload *upayload;
+	size_t datalen = prep->datalen;
+
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
+	if (!upayload)
+		return -ENOMEM;
+
+	/* attach the data */
+	prep->quotalen = datalen;
+	prep->payload.data[0] = upayload;
+	upayload->datalen = datalen;
+	memcpy(upayload->data, prep->data, datalen);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(user_preparse);
+
+/*
+ * Free a preparse of a user defined key payload
+ */
+void user_free_preparse(struct key_preparsed_payload *prep)
+{
+	kzfree(prep->payload.data[0]);
+}
+EXPORT_SYMBOL_GPL(user_free_preparse);
+
+static void user_free_payload_rcu(struct rcu_head *head)
+{
+	struct user_key_payload *payload;
+
+	payload = container_of(head, struct user_key_payload, rcu);
+	kzfree(payload);
+}
+
+/*
+ * update a user defined key
+ * - the key's semaphore is write-locked
+ */
+int user_update(struct key *key, struct key_preparsed_payload *prep)
+{
+	struct user_key_payload *zap = NULL;
+	int ret;
+
+	/* check the quota and attach the new data */
+	ret = key_payload_reserve(key, prep->datalen);
+	if (ret < 0)
+		return ret;
+
+	/* attach the new data, displacing the old */
+	key->expiry = prep->expiry;
+	if (key_is_positive(key))
+		zap = dereference_key_locked(key);
+	rcu_assign_keypointer(key, prep->payload.data[0]);
+	prep->payload.data[0] = NULL;
+
+	if (zap)
+		call_rcu(&zap->rcu, user_free_payload_rcu);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(user_update);
+
+/*
+ * dispose of the links from a revoked keyring
+ * - called with the key sem write-locked
+ */
+void user_revoke(struct key *key)
+{
+	struct user_key_payload *upayload = user_key_payload_locked(key);
+
+	/* clear the quota */
+	key_payload_reserve(key, 0);
+
+	if (upayload) {
+		rcu_assign_keypointer(key, NULL);
+		call_rcu(&upayload->rcu, user_free_payload_rcu);
+	}
+}
+
+EXPORT_SYMBOL(user_revoke);
+
+/*
+ * dispose of the data dangling from the corpse of a user key
+ */
+void user_destroy(struct key *key)
+{
+	struct user_key_payload *upayload = key->payload.data[0];
+
+	kzfree(upayload);
+}
+
+EXPORT_SYMBOL_GPL(user_destroy);
+
+/*
+ * describe the user key
+ */
+void user_describe(const struct key *key, struct seq_file *m)
+{
+	seq_puts(m, key->description);
+	if (key_is_positive(key))
+		seq_printf(m, ": %u", key->datalen);
+}
+
+EXPORT_SYMBOL_GPL(user_describe);
+
+/*
+ * read the key data
+ * - the key's semaphore is read-locked
+ */
+long user_read(const struct key *key, char *buffer, size_t buflen)
+{
+	const struct user_key_payload *upayload;
+	long ret;
+
+	upayload = user_key_payload_locked(key);
+	ret = upayload->datalen;
+
+	/* we can return the data as is */
+	if (buffer && buflen > 0) {
+		if (buflen > upayload->datalen)
+			buflen = upayload->datalen;
+
+		memcpy(buffer, upayload->data, buflen);
+	}
+
+	return ret;
+}
+
+EXPORT_SYMBOL_GPL(user_read);
+
+/* Vet the description for a "logon" key */
+static int logon_vet_description(const char *desc)
+{
+	char *p;
+
+	/* require a "qualified" description string */
+	p = strchr(desc, ':');
+	if (!p)
+		return -EINVAL;
+
+	/* also reject description with ':' as first char */
+	if (p == desc)
+		return -EINVAL;
+
+	return 0;
+}