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-rw-r--r--crypto/af_alg.c1320
1 files changed, 1320 insertions, 0 deletions
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
new file mode 100644
index 0000000000..68cc9290ca
--- /dev/null
+++ b/crypto/af_alg.c
@@ -0,0 +1,1320 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * af_alg: User-space algorithm interface
+ *
+ * This file provides the user-space API for algorithms.
+ *
+ * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/atomic.h>
+#include <crypto/if_alg.h>
+#include <linux/crypto.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/key.h>
+#include <linux/key-type.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/sched/signal.h>
+#include <linux/security.h>
+#include <linux/string.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <keys/encrypted-type.h>
+
+struct alg_type_list {
+ const struct af_alg_type *type;
+ struct list_head list;
+};
+
+static struct proto alg_proto = {
+ .name = "ALG",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct alg_sock),
+};
+
+static LIST_HEAD(alg_types);
+static DECLARE_RWSEM(alg_types_sem);
+
+static const struct af_alg_type *alg_get_type(const char *name)
+{
+ const struct af_alg_type *type = ERR_PTR(-ENOENT);
+ struct alg_type_list *node;
+
+ down_read(&alg_types_sem);
+ list_for_each_entry(node, &alg_types, list) {
+ if (strcmp(node->type->name, name))
+ continue;
+
+ if (try_module_get(node->type->owner))
+ type = node->type;
+ break;
+ }
+ up_read(&alg_types_sem);
+
+ return type;
+}
+
+int af_alg_register_type(const struct af_alg_type *type)
+{
+ struct alg_type_list *node;
+ int err = -EEXIST;
+
+ down_write(&alg_types_sem);
+ list_for_each_entry(node, &alg_types, list) {
+ if (!strcmp(node->type->name, type->name))
+ goto unlock;
+ }
+
+ node = kmalloc(sizeof(*node), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!node)
+ goto unlock;
+
+ type->ops->owner = THIS_MODULE;
+ if (type->ops_nokey)
+ type->ops_nokey->owner = THIS_MODULE;
+ node->type = type;
+ list_add(&node->list, &alg_types);
+ err = 0;
+
+unlock:
+ up_write(&alg_types_sem);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_register_type);
+
+int af_alg_unregister_type(const struct af_alg_type *type)
+{
+ struct alg_type_list *node;
+ int err = -ENOENT;
+
+ down_write(&alg_types_sem);
+ list_for_each_entry(node, &alg_types, list) {
+ if (strcmp(node->type->name, type->name))
+ continue;
+
+ list_del(&node->list);
+ kfree(node);
+ err = 0;
+ break;
+ }
+ up_write(&alg_types_sem);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_unregister_type);
+
+static void alg_do_release(const struct af_alg_type *type, void *private)
+{
+ if (!type)
+ return;
+
+ type->release(private);
+ module_put(type->owner);
+}
+
+int af_alg_release(struct socket *sock)
+{
+ if (sock->sk) {
+ sock_put(sock->sk);
+ sock->sk = NULL;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(af_alg_release);
+
+void af_alg_release_parent(struct sock *sk)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ unsigned int nokey = atomic_read(&ask->nokey_refcnt);
+
+ sk = ask->parent;
+ ask = alg_sk(sk);
+
+ if (nokey)
+ atomic_dec(&ask->nokey_refcnt);
+
+ if (atomic_dec_and_test(&ask->refcnt))
+ sock_put(sk);
+}
+EXPORT_SYMBOL_GPL(af_alg_release_parent);
+
+static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+ const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY;
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct sockaddr_alg_new *sa = (void *)uaddr;
+ const struct af_alg_type *type;
+ void *private;
+ int err;
+
+ if (sock->state == SS_CONNECTED)
+ return -EINVAL;
+
+ BUILD_BUG_ON(offsetof(struct sockaddr_alg_new, salg_name) !=
+ offsetof(struct sockaddr_alg, salg_name));
+ BUILD_BUG_ON(offsetof(struct sockaddr_alg, salg_name) != sizeof(*sa));
+
+ if (addr_len < sizeof(*sa) + 1)
+ return -EINVAL;
+
+ /* If caller uses non-allowed flag, return error. */
+ if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed))
+ return -EINVAL;
+
+ sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
+ sa->salg_name[addr_len - sizeof(*sa) - 1] = 0;
+
+ type = alg_get_type(sa->salg_type);
+ if (PTR_ERR(type) == -ENOENT) {
+ request_module("algif-%s", sa->salg_type);
+ type = alg_get_type(sa->salg_type);
+ }
+
+ if (IS_ERR(type))
+ return PTR_ERR(type);
+
+ private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask);
+ if (IS_ERR(private)) {
+ module_put(type->owner);
+ return PTR_ERR(private);
+ }
+
+ err = -EBUSY;
+ lock_sock(sk);
+ if (atomic_read(&ask->refcnt))
+ goto unlock;
+
+ swap(ask->type, type);
+ swap(ask->private, private);
+
+ err = 0;
+
+unlock:
+ release_sock(sk);
+
+ alg_do_release(type, private);
+
+ return err;
+}
+
+static int alg_setkey(struct sock *sk, sockptr_t ukey, unsigned int keylen)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ const struct af_alg_type *type = ask->type;
+ u8 *key;
+ int err;
+
+ key = sock_kmalloc(sk, keylen, GFP_KERNEL);
+ if (!key)
+ return -ENOMEM;
+
+ err = -EFAULT;
+ if (copy_from_sockptr(key, ukey, keylen))
+ goto out;
+
+ err = type->setkey(ask->private, key, keylen);
+
+out:
+ sock_kzfree_s(sk, key, keylen);
+
+ return err;
+}
+
+#ifdef CONFIG_KEYS
+
+static const u8 *key_data_ptr_user(const struct key *key,
+ unsigned int *datalen)
+{
+ const struct user_key_payload *ukp;
+
+ ukp = user_key_payload_locked(key);
+ if (IS_ERR_OR_NULL(ukp))
+ return ERR_PTR(-EKEYREVOKED);
+
+ *datalen = key->datalen;
+
+ return ukp->data;
+}
+
+static const u8 *key_data_ptr_encrypted(const struct key *key,
+ unsigned int *datalen)
+{
+ const struct encrypted_key_payload *ekp;
+
+ ekp = dereference_key_locked(key);
+ if (IS_ERR_OR_NULL(ekp))
+ return ERR_PTR(-EKEYREVOKED);
+
+ *datalen = ekp->decrypted_datalen;
+
+ return ekp->decrypted_data;
+}
+
+static const u8 *key_data_ptr_trusted(const struct key *key,
+ unsigned int *datalen)
+{
+ const struct trusted_key_payload *tkp;
+
+ tkp = dereference_key_locked(key);
+ if (IS_ERR_OR_NULL(tkp))
+ return ERR_PTR(-EKEYREVOKED);
+
+ *datalen = tkp->key_len;
+
+ return tkp->key;
+}
+
+static struct key *lookup_key(key_serial_t serial)
+{
+ key_ref_t key_ref;
+
+ key_ref = lookup_user_key(serial, 0, KEY_NEED_SEARCH);
+ if (IS_ERR(key_ref))
+ return ERR_CAST(key_ref);
+
+ return key_ref_to_ptr(key_ref);
+}
+
+static int alg_setkey_by_key_serial(struct alg_sock *ask, sockptr_t optval,
+ unsigned int optlen)
+{
+ const struct af_alg_type *type = ask->type;
+ u8 *key_data = NULL;
+ unsigned int key_datalen;
+ key_serial_t serial;
+ struct key *key;
+ const u8 *ret;
+ int err;
+
+ if (optlen != sizeof(serial))
+ return -EINVAL;
+
+ if (copy_from_sockptr(&serial, optval, optlen))
+ return -EFAULT;
+
+ key = lookup_key(serial);
+ if (IS_ERR(key))
+ return PTR_ERR(key);
+
+ down_read(&key->sem);
+
+ ret = ERR_PTR(-ENOPROTOOPT);
+ if (!strcmp(key->type->name, "user") ||
+ !strcmp(key->type->name, "logon")) {
+ ret = key_data_ptr_user(key, &key_datalen);
+ } else if (IS_REACHABLE(CONFIG_ENCRYPTED_KEYS) &&
+ !strcmp(key->type->name, "encrypted")) {
+ ret = key_data_ptr_encrypted(key, &key_datalen);
+ } else if (IS_REACHABLE(CONFIG_TRUSTED_KEYS) &&
+ !strcmp(key->type->name, "trusted")) {
+ ret = key_data_ptr_trusted(key, &key_datalen);
+ }
+
+ if (IS_ERR(ret)) {
+ up_read(&key->sem);
+ key_put(key);
+ return PTR_ERR(ret);
+ }
+
+ key_data = sock_kmalloc(&ask->sk, key_datalen, GFP_KERNEL);
+ if (!key_data) {
+ up_read(&key->sem);
+ key_put(key);
+ return -ENOMEM;
+ }
+
+ memcpy(key_data, ret, key_datalen);
+
+ up_read(&key->sem);
+ key_put(key);
+
+ err = type->setkey(ask->private, key_data, key_datalen);
+
+ sock_kzfree_s(&ask->sk, key_data, key_datalen);
+
+ return err;
+}
+
+#else
+
+static inline int alg_setkey_by_key_serial(struct alg_sock *ask,
+ sockptr_t optval,
+ unsigned int optlen)
+{
+ return -ENOPROTOOPT;
+}
+
+#endif
+
+static int alg_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ const struct af_alg_type *type;
+ int err = -EBUSY;
+
+ lock_sock(sk);
+ if (atomic_read(&ask->refcnt) != atomic_read(&ask->nokey_refcnt))
+ goto unlock;
+
+ type = ask->type;
+
+ err = -ENOPROTOOPT;
+ if (level != SOL_ALG || !type)
+ goto unlock;
+
+ switch (optname) {
+ case ALG_SET_KEY:
+ case ALG_SET_KEY_BY_KEY_SERIAL:
+ if (sock->state == SS_CONNECTED)
+ goto unlock;
+ if (!type->setkey)
+ goto unlock;
+
+ if (optname == ALG_SET_KEY_BY_KEY_SERIAL)
+ err = alg_setkey_by_key_serial(ask, optval, optlen);
+ else
+ err = alg_setkey(sk, optval, optlen);
+ break;
+ case ALG_SET_AEAD_AUTHSIZE:
+ if (sock->state == SS_CONNECTED)
+ goto unlock;
+ if (!type->setauthsize)
+ goto unlock;
+ err = type->setauthsize(ask->private, optlen);
+ break;
+ case ALG_SET_DRBG_ENTROPY:
+ if (sock->state == SS_CONNECTED)
+ goto unlock;
+ if (!type->setentropy)
+ goto unlock;
+
+ err = type->setentropy(ask->private, optval, optlen);
+ }
+
+unlock:
+ release_sock(sk);
+
+ return err;
+}
+
+int af_alg_accept(struct sock *sk, struct socket *newsock, bool kern)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ const struct af_alg_type *type;
+ struct sock *sk2;
+ unsigned int nokey;
+ int err;
+
+ lock_sock(sk);
+ type = ask->type;
+
+ err = -EINVAL;
+ if (!type)
+ goto unlock;
+
+ sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto, kern);
+ err = -ENOMEM;
+ if (!sk2)
+ goto unlock;
+
+ sock_init_data(newsock, sk2);
+ security_sock_graft(sk2, newsock);
+ security_sk_clone(sk, sk2);
+
+ /*
+ * newsock->ops assigned here to allow type->accept call to override
+ * them when required.
+ */
+ newsock->ops = type->ops;
+ err = type->accept(ask->private, sk2);
+
+ nokey = err == -ENOKEY;
+ if (nokey && type->accept_nokey)
+ err = type->accept_nokey(ask->private, sk2);
+
+ if (err)
+ goto unlock;
+
+ if (atomic_inc_return_relaxed(&ask->refcnt) == 1)
+ sock_hold(sk);
+ if (nokey) {
+ atomic_inc(&ask->nokey_refcnt);
+ atomic_set(&alg_sk(sk2)->nokey_refcnt, 1);
+ }
+ alg_sk(sk2)->parent = sk;
+ alg_sk(sk2)->type = type;
+
+ newsock->state = SS_CONNECTED;
+
+ if (nokey)
+ newsock->ops = type->ops_nokey;
+
+ err = 0;
+
+unlock:
+ release_sock(sk);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_accept);
+
+static int alg_accept(struct socket *sock, struct socket *newsock, int flags,
+ bool kern)
+{
+ return af_alg_accept(sock->sk, newsock, kern);
+}
+
+static const struct proto_ops alg_proto_ops = {
+ .family = PF_ALG,
+ .owner = THIS_MODULE,
+
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .getname = sock_no_getname,
+ .ioctl = sock_no_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .mmap = sock_no_mmap,
+ .sendmsg = sock_no_sendmsg,
+ .recvmsg = sock_no_recvmsg,
+
+ .bind = alg_bind,
+ .release = af_alg_release,
+ .setsockopt = alg_setsockopt,
+ .accept = alg_accept,
+};
+
+static void alg_sock_destruct(struct sock *sk)
+{
+ struct alg_sock *ask = alg_sk(sk);
+
+ alg_do_release(ask->type, ask->private);
+}
+
+static int alg_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk;
+ int err;
+
+ if (sock->type != SOCK_SEQPACKET)
+ return -ESOCKTNOSUPPORT;
+ if (protocol != 0)
+ return -EPROTONOSUPPORT;
+
+ err = -ENOMEM;
+ sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto, kern);
+ if (!sk)
+ goto out;
+
+ sock->ops = &alg_proto_ops;
+ sock_init_data(sock, sk);
+
+ sk->sk_destruct = alg_sock_destruct;
+
+ return 0;
+out:
+ return err;
+}
+
+static const struct net_proto_family alg_family = {
+ .family = PF_ALG,
+ .create = alg_create,
+ .owner = THIS_MODULE,
+};
+
+static void af_alg_link_sg(struct af_alg_sgl *sgl_prev,
+ struct af_alg_sgl *sgl_new)
+{
+ sg_unmark_end(sgl_prev->sgt.sgl + sgl_prev->sgt.nents - 1);
+ sg_chain(sgl_prev->sgt.sgl, sgl_prev->sgt.nents + 1, sgl_new->sgt.sgl);
+}
+
+void af_alg_free_sg(struct af_alg_sgl *sgl)
+{
+ int i;
+
+ if (sgl->sgt.sgl) {
+ if (sgl->need_unpin)
+ for (i = 0; i < sgl->sgt.nents; i++)
+ unpin_user_page(sg_page(&sgl->sgt.sgl[i]));
+ if (sgl->sgt.sgl != sgl->sgl)
+ kvfree(sgl->sgt.sgl);
+ sgl->sgt.sgl = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(af_alg_free_sg);
+
+static int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
+{
+ struct cmsghdr *cmsg;
+
+ for_each_cmsghdr(cmsg, msg) {
+ if (!CMSG_OK(msg, cmsg))
+ return -EINVAL;
+ if (cmsg->cmsg_level != SOL_ALG)
+ continue;
+
+ switch (cmsg->cmsg_type) {
+ case ALG_SET_IV:
+ if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
+ return -EINVAL;
+ con->iv = (void *)CMSG_DATA(cmsg);
+ if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
+ sizeof(*con->iv)))
+ return -EINVAL;
+ break;
+
+ case ALG_SET_OP:
+ if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
+ return -EINVAL;
+ con->op = *(u32 *)CMSG_DATA(cmsg);
+ break;
+
+ case ALG_SET_AEAD_ASSOCLEN:
+ if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
+ return -EINVAL;
+ con->aead_assoclen = *(u32 *)CMSG_DATA(cmsg);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * af_alg_alloc_tsgl - allocate the TX SGL
+ *
+ * @sk: socket of connection to user space
+ * Return: 0 upon success, < 0 upon error
+ */
+static int af_alg_alloc_tsgl(struct sock *sk)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct af_alg_tsgl *sgl;
+ struct scatterlist *sg = NULL;
+
+ sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl, list);
+ if (!list_empty(&ctx->tsgl_list))
+ sg = sgl->sg;
+
+ if (!sg || sgl->cur >= MAX_SGL_ENTS) {
+ sgl = sock_kmalloc(sk,
+ struct_size(sgl, sg, (MAX_SGL_ENTS + 1)),
+ GFP_KERNEL);
+ if (!sgl)
+ return -ENOMEM;
+
+ sg_init_table(sgl->sg, MAX_SGL_ENTS + 1);
+ sgl->cur = 0;
+
+ if (sg)
+ sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg);
+
+ list_add_tail(&sgl->list, &ctx->tsgl_list);
+ }
+
+ return 0;
+}
+
+/**
+ * af_alg_count_tsgl - Count number of TX SG entries
+ *
+ * The counting starts from the beginning of the SGL to @bytes. If
+ * an @offset is provided, the counting of the SG entries starts at the @offset.
+ *
+ * @sk: socket of connection to user space
+ * @bytes: Count the number of SG entries holding given number of bytes.
+ * @offset: Start the counting of SG entries from the given offset.
+ * Return: Number of TX SG entries found given the constraints
+ */
+unsigned int af_alg_count_tsgl(struct sock *sk, size_t bytes, size_t offset)
+{
+ const struct alg_sock *ask = alg_sk(sk);
+ const struct af_alg_ctx *ctx = ask->private;
+ const struct af_alg_tsgl *sgl;
+ unsigned int i;
+ unsigned int sgl_count = 0;
+
+ if (!bytes)
+ return 0;
+
+ list_for_each_entry(sgl, &ctx->tsgl_list, list) {
+ const struct scatterlist *sg = sgl->sg;
+
+ for (i = 0; i < sgl->cur; i++) {
+ size_t bytes_count;
+
+ /* Skip offset */
+ if (offset >= sg[i].length) {
+ offset -= sg[i].length;
+ bytes -= sg[i].length;
+ continue;
+ }
+
+ bytes_count = sg[i].length - offset;
+
+ offset = 0;
+ sgl_count++;
+
+ /* If we have seen requested number of bytes, stop */
+ if (bytes_count >= bytes)
+ return sgl_count;
+
+ bytes -= bytes_count;
+ }
+ }
+
+ return sgl_count;
+}
+EXPORT_SYMBOL_GPL(af_alg_count_tsgl);
+
+/**
+ * af_alg_pull_tsgl - Release the specified buffers from TX SGL
+ *
+ * If @dst is non-null, reassign the pages to @dst. The caller must release
+ * the pages. If @dst_offset is given only reassign the pages to @dst starting
+ * at the @dst_offset (byte). The caller must ensure that @dst is large
+ * enough (e.g. by using af_alg_count_tsgl with the same offset).
+ *
+ * @sk: socket of connection to user space
+ * @used: Number of bytes to pull from TX SGL
+ * @dst: If non-NULL, buffer is reassigned to dst SGL instead of releasing. The
+ * caller must release the buffers in dst.
+ * @dst_offset: Reassign the TX SGL from given offset. All buffers before
+ * reaching the offset is released.
+ */
+void af_alg_pull_tsgl(struct sock *sk, size_t used, struct scatterlist *dst,
+ size_t dst_offset)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct af_alg_tsgl *sgl;
+ struct scatterlist *sg;
+ unsigned int i, j = 0;
+
+ while (!list_empty(&ctx->tsgl_list)) {
+ sgl = list_first_entry(&ctx->tsgl_list, struct af_alg_tsgl,
+ list);
+ sg = sgl->sg;
+
+ for (i = 0; i < sgl->cur; i++) {
+ size_t plen = min_t(size_t, used, sg[i].length);
+ struct page *page = sg_page(sg + i);
+
+ if (!page)
+ continue;
+
+ /*
+ * Assumption: caller created af_alg_count_tsgl(len)
+ * SG entries in dst.
+ */
+ if (dst) {
+ if (dst_offset >= plen) {
+ /* discard page before offset */
+ dst_offset -= plen;
+ } else {
+ /* reassign page to dst after offset */
+ get_page(page);
+ sg_set_page(dst + j, page,
+ plen - dst_offset,
+ sg[i].offset + dst_offset);
+ dst_offset = 0;
+ j++;
+ }
+ }
+
+ sg[i].length -= plen;
+ sg[i].offset += plen;
+
+ used -= plen;
+ ctx->used -= plen;
+
+ if (sg[i].length)
+ return;
+
+ put_page(page);
+ sg_assign_page(sg + i, NULL);
+ }
+
+ list_del(&sgl->list);
+ sock_kfree_s(sk, sgl, struct_size(sgl, sg, MAX_SGL_ENTS + 1));
+ }
+
+ if (!ctx->used)
+ ctx->merge = 0;
+ ctx->init = ctx->more;
+}
+EXPORT_SYMBOL_GPL(af_alg_pull_tsgl);
+
+/**
+ * af_alg_free_areq_sgls - Release TX and RX SGLs of the request
+ *
+ * @areq: Request holding the TX and RX SGL
+ */
+static void af_alg_free_areq_sgls(struct af_alg_async_req *areq)
+{
+ struct sock *sk = areq->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct af_alg_rsgl *rsgl, *tmp;
+ struct scatterlist *tsgl;
+ struct scatterlist *sg;
+ unsigned int i;
+
+ list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) {
+ atomic_sub(rsgl->sg_num_bytes, &ctx->rcvused);
+ af_alg_free_sg(&rsgl->sgl);
+ list_del(&rsgl->list);
+ if (rsgl != &areq->first_rsgl)
+ sock_kfree_s(sk, rsgl, sizeof(*rsgl));
+ }
+
+ tsgl = areq->tsgl;
+ if (tsgl) {
+ for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
+ if (!sg_page(sg))
+ continue;
+ put_page(sg_page(sg));
+ }
+
+ sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
+ }
+}
+
+/**
+ * af_alg_wait_for_wmem - wait for availability of writable memory
+ *
+ * @sk: socket of connection to user space
+ * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
+ * Return: 0 when writable memory is available, < 0 upon error
+ */
+static int af_alg_wait_for_wmem(struct sock *sk, unsigned int flags)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ int err = -ERESTARTSYS;
+ long timeout;
+
+ if (flags & MSG_DONTWAIT)
+ return -EAGAIN;
+
+ sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ for (;;) {
+ if (signal_pending(current))
+ break;
+ timeout = MAX_SCHEDULE_TIMEOUT;
+ if (sk_wait_event(sk, &timeout, af_alg_writable(sk), &wait)) {
+ err = 0;
+ break;
+ }
+ }
+ remove_wait_queue(sk_sleep(sk), &wait);
+
+ return err;
+}
+
+/**
+ * af_alg_wmem_wakeup - wakeup caller when writable memory is available
+ *
+ * @sk: socket of connection to user space
+ */
+void af_alg_wmem_wakeup(struct sock *sk)
+{
+ struct socket_wq *wq;
+
+ if (!af_alg_writable(sk))
+ return;
+
+ rcu_read_lock();
+ wq = rcu_dereference(sk->sk_wq);
+ if (skwq_has_sleeper(wq))
+ wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN |
+ EPOLLRDNORM |
+ EPOLLRDBAND);
+ sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(af_alg_wmem_wakeup);
+
+/**
+ * af_alg_wait_for_data - wait for availability of TX data
+ *
+ * @sk: socket of connection to user space
+ * @flags: If MSG_DONTWAIT is set, then only report if function would sleep
+ * @min: Set to minimum request size if partial requests are allowed.
+ * Return: 0 when writable memory is available, < 0 upon error
+ */
+int af_alg_wait_for_data(struct sock *sk, unsigned flags, unsigned min)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ long timeout;
+ int err = -ERESTARTSYS;
+
+ if (flags & MSG_DONTWAIT)
+ return -EAGAIN;
+
+ sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ for (;;) {
+ if (signal_pending(current))
+ break;
+ timeout = MAX_SCHEDULE_TIMEOUT;
+ if (sk_wait_event(sk, &timeout,
+ ctx->init && (!ctx->more ||
+ (min && ctx->used >= min)),
+ &wait)) {
+ err = 0;
+ break;
+ }
+ }
+ remove_wait_queue(sk_sleep(sk), &wait);
+
+ sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_wait_for_data);
+
+/**
+ * af_alg_data_wakeup - wakeup caller when new data can be sent to kernel
+ *
+ * @sk: socket of connection to user space
+ */
+static void af_alg_data_wakeup(struct sock *sk)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct socket_wq *wq;
+
+ if (!ctx->used)
+ return;
+
+ rcu_read_lock();
+ wq = rcu_dereference(sk->sk_wq);
+ if (skwq_has_sleeper(wq))
+ wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
+ EPOLLRDNORM |
+ EPOLLRDBAND);
+ sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
+ rcu_read_unlock();
+}
+
+/**
+ * af_alg_sendmsg - implementation of sendmsg system call handler
+ *
+ * The sendmsg system call handler obtains the user data and stores it
+ * in ctx->tsgl_list. This implies allocation of the required numbers of
+ * struct af_alg_tsgl.
+ *
+ * In addition, the ctx is filled with the information sent via CMSG.
+ *
+ * @sock: socket of connection to user space
+ * @msg: message from user space
+ * @size: size of message from user space
+ * @ivsize: the size of the IV for the cipher operation to verify that the
+ * user-space-provided IV has the right size
+ * Return: the number of copied data upon success, < 0 upon error
+ */
+int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
+ unsigned int ivsize)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ struct af_alg_tsgl *sgl;
+ struct af_alg_control con = {};
+ long copied = 0;
+ bool enc = false;
+ bool init = false;
+ int err = 0;
+
+ if (msg->msg_controllen) {
+ err = af_alg_cmsg_send(msg, &con);
+ if (err)
+ return err;
+
+ init = true;
+ switch (con.op) {
+ case ALG_OP_ENCRYPT:
+ enc = true;
+ break;
+ case ALG_OP_DECRYPT:
+ enc = false;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (con.iv && con.iv->ivlen != ivsize)
+ return -EINVAL;
+ }
+
+ lock_sock(sk);
+ if (ctx->init && !ctx->more) {
+ if (ctx->used) {
+ err = -EINVAL;
+ goto unlock;
+ }
+
+ pr_info_once(
+ "%s sent an empty control message without MSG_MORE.\n",
+ current->comm);
+ }
+ ctx->init = true;
+
+ if (init) {
+ ctx->enc = enc;
+ if (con.iv)
+ memcpy(ctx->iv, con.iv->iv, ivsize);
+
+ ctx->aead_assoclen = con.aead_assoclen;
+ }
+
+ while (size) {
+ struct scatterlist *sg;
+ size_t len = size;
+ ssize_t plen;
+
+ /* use the existing memory in an allocated page */
+ if (ctx->merge && !(msg->msg_flags & MSG_SPLICE_PAGES)) {
+ sgl = list_entry(ctx->tsgl_list.prev,
+ struct af_alg_tsgl, list);
+ sg = sgl->sg + sgl->cur - 1;
+ len = min_t(size_t, len,
+ PAGE_SIZE - sg->offset - sg->length);
+
+ err = memcpy_from_msg(page_address(sg_page(sg)) +
+ sg->offset + sg->length,
+ msg, len);
+ if (err)
+ goto unlock;
+
+ sg->length += len;
+ ctx->merge = (sg->offset + sg->length) &
+ (PAGE_SIZE - 1);
+
+ ctx->used += len;
+ copied += len;
+ size -= len;
+ continue;
+ }
+
+ if (!af_alg_writable(sk)) {
+ err = af_alg_wait_for_wmem(sk, msg->msg_flags);
+ if (err)
+ goto unlock;
+ }
+
+ /* allocate a new page */
+ len = min_t(unsigned long, len, af_alg_sndbuf(sk));
+
+ err = af_alg_alloc_tsgl(sk);
+ if (err)
+ goto unlock;
+
+ sgl = list_entry(ctx->tsgl_list.prev, struct af_alg_tsgl,
+ list);
+ sg = sgl->sg;
+ if (sgl->cur)
+ sg_unmark_end(sg + sgl->cur - 1);
+
+ if (msg->msg_flags & MSG_SPLICE_PAGES) {
+ struct sg_table sgtable = {
+ .sgl = sg,
+ .nents = sgl->cur,
+ .orig_nents = sgl->cur,
+ };
+
+ plen = extract_iter_to_sg(&msg->msg_iter, len, &sgtable,
+ MAX_SGL_ENTS - sgl->cur, 0);
+ if (plen < 0) {
+ err = plen;
+ goto unlock;
+ }
+
+ for (; sgl->cur < sgtable.nents; sgl->cur++)
+ get_page(sg_page(&sg[sgl->cur]));
+ len -= plen;
+ ctx->used += plen;
+ copied += plen;
+ size -= plen;
+ ctx->merge = 0;
+ } else {
+ do {
+ struct page *pg;
+ unsigned int i = sgl->cur;
+
+ plen = min_t(size_t, len, PAGE_SIZE);
+
+ pg = alloc_page(GFP_KERNEL);
+ if (!pg) {
+ err = -ENOMEM;
+ goto unlock;
+ }
+
+ sg_assign_page(sg + i, pg);
+
+ err = memcpy_from_msg(
+ page_address(sg_page(sg + i)),
+ msg, plen);
+ if (err) {
+ __free_page(sg_page(sg + i));
+ sg_assign_page(sg + i, NULL);
+ goto unlock;
+ }
+
+ sg[i].length = plen;
+ len -= plen;
+ ctx->used += plen;
+ copied += plen;
+ size -= plen;
+ sgl->cur++;
+ } while (len && sgl->cur < MAX_SGL_ENTS);
+
+ ctx->merge = plen & (PAGE_SIZE - 1);
+ }
+
+ if (!size)
+ sg_mark_end(sg + sgl->cur - 1);
+ }
+
+ err = 0;
+
+ ctx->more = msg->msg_flags & MSG_MORE;
+
+unlock:
+ af_alg_data_wakeup(sk);
+ release_sock(sk);
+
+ return copied ?: err;
+}
+EXPORT_SYMBOL_GPL(af_alg_sendmsg);
+
+/**
+ * af_alg_free_resources - release resources required for crypto request
+ * @areq: Request holding the TX and RX SGL
+ */
+void af_alg_free_resources(struct af_alg_async_req *areq)
+{
+ struct sock *sk = areq->sk;
+ struct af_alg_ctx *ctx;
+
+ af_alg_free_areq_sgls(areq);
+ sock_kfree_s(sk, areq, areq->areqlen);
+
+ ctx = alg_sk(sk)->private;
+ ctx->inflight = false;
+}
+EXPORT_SYMBOL_GPL(af_alg_free_resources);
+
+/**
+ * af_alg_async_cb - AIO callback handler
+ * @data: async request completion data
+ * @err: if non-zero, error result to be returned via ki_complete();
+ * otherwise return the AIO output length via ki_complete().
+ *
+ * This handler cleans up the struct af_alg_async_req upon completion of the
+ * AIO operation.
+ *
+ * The number of bytes to be generated with the AIO operation must be set
+ * in areq->outlen before the AIO callback handler is invoked.
+ */
+void af_alg_async_cb(void *data, int err)
+{
+ struct af_alg_async_req *areq = data;
+ struct sock *sk = areq->sk;
+ struct kiocb *iocb = areq->iocb;
+ unsigned int resultlen;
+
+ /* Buffer size written by crypto operation. */
+ resultlen = areq->outlen;
+
+ af_alg_free_resources(areq);
+ sock_put(sk);
+
+ iocb->ki_complete(iocb, err ? err : (int)resultlen);
+}
+EXPORT_SYMBOL_GPL(af_alg_async_cb);
+
+/**
+ * af_alg_poll - poll system call handler
+ * @file: file pointer
+ * @sock: socket to poll
+ * @wait: poll_table
+ */
+__poll_t af_alg_poll(struct file *file, struct socket *sock,
+ poll_table *wait)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ __poll_t mask;
+
+ sock_poll_wait(file, sock, wait);
+ mask = 0;
+
+ if (!ctx->more || ctx->used)
+ mask |= EPOLLIN | EPOLLRDNORM;
+
+ if (af_alg_writable(sk))
+ mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
+
+ return mask;
+}
+EXPORT_SYMBOL_GPL(af_alg_poll);
+
+/**
+ * af_alg_alloc_areq - allocate struct af_alg_async_req
+ *
+ * @sk: socket of connection to user space
+ * @areqlen: size of struct af_alg_async_req + crypto_*_reqsize
+ * Return: allocated data structure or ERR_PTR upon error
+ */
+struct af_alg_async_req *af_alg_alloc_areq(struct sock *sk,
+ unsigned int areqlen)
+{
+ struct af_alg_ctx *ctx = alg_sk(sk)->private;
+ struct af_alg_async_req *areq;
+
+ /* Only one AIO request can be in flight. */
+ if (ctx->inflight)
+ return ERR_PTR(-EBUSY);
+
+ areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
+ if (unlikely(!areq))
+ return ERR_PTR(-ENOMEM);
+
+ ctx->inflight = true;
+
+ areq->areqlen = areqlen;
+ areq->sk = sk;
+ areq->first_rsgl.sgl.sgt.sgl = areq->first_rsgl.sgl.sgl;
+ areq->last_rsgl = NULL;
+ INIT_LIST_HEAD(&areq->rsgl_list);
+ areq->tsgl = NULL;
+ areq->tsgl_entries = 0;
+
+ return areq;
+}
+EXPORT_SYMBOL_GPL(af_alg_alloc_areq);
+
+/**
+ * af_alg_get_rsgl - create the RX SGL for the output data from the crypto
+ * operation
+ *
+ * @sk: socket of connection to user space
+ * @msg: user space message
+ * @flags: flags used to invoke recvmsg with
+ * @areq: instance of the cryptographic request that will hold the RX SGL
+ * @maxsize: maximum number of bytes to be pulled from user space
+ * @outlen: number of bytes in the RX SGL
+ * Return: 0 on success, < 0 upon error
+ */
+int af_alg_get_rsgl(struct sock *sk, struct msghdr *msg, int flags,
+ struct af_alg_async_req *areq, size_t maxsize,
+ size_t *outlen)
+{
+ struct alg_sock *ask = alg_sk(sk);
+ struct af_alg_ctx *ctx = ask->private;
+ size_t len = 0;
+
+ while (maxsize > len && msg_data_left(msg)) {
+ struct af_alg_rsgl *rsgl;
+ ssize_t err;
+ size_t seglen;
+
+ /* limit the amount of readable buffers */
+ if (!af_alg_readable(sk))
+ break;
+
+ seglen = min_t(size_t, (maxsize - len),
+ msg_data_left(msg));
+
+ if (list_empty(&areq->rsgl_list)) {
+ rsgl = &areq->first_rsgl;
+ } else {
+ rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
+ if (unlikely(!rsgl))
+ return -ENOMEM;
+ }
+
+ rsgl->sgl.need_unpin =
+ iov_iter_extract_will_pin(&msg->msg_iter);
+ rsgl->sgl.sgt.sgl = rsgl->sgl.sgl;
+ rsgl->sgl.sgt.nents = 0;
+ rsgl->sgl.sgt.orig_nents = 0;
+ list_add_tail(&rsgl->list, &areq->rsgl_list);
+
+ sg_init_table(rsgl->sgl.sgt.sgl, ALG_MAX_PAGES);
+ err = extract_iter_to_sg(&msg->msg_iter, seglen, &rsgl->sgl.sgt,
+ ALG_MAX_PAGES, 0);
+ if (err < 0) {
+ rsgl->sg_num_bytes = 0;
+ return err;
+ }
+
+ sg_mark_end(rsgl->sgl.sgt.sgl + rsgl->sgl.sgt.nents - 1);
+
+ /* chain the new scatterlist with previous one */
+ if (areq->last_rsgl)
+ af_alg_link_sg(&areq->last_rsgl->sgl, &rsgl->sgl);
+
+ areq->last_rsgl = rsgl;
+ len += err;
+ atomic_add(err, &ctx->rcvused);
+ rsgl->sg_num_bytes = err;
+ }
+
+ *outlen = len;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(af_alg_get_rsgl);
+
+static int __init af_alg_init(void)
+{
+ int err = proto_register(&alg_proto, 0);
+
+ if (err)
+ goto out;
+
+ err = sock_register(&alg_family);
+ if (err != 0)
+ goto out_unregister_proto;
+
+out:
+ return err;
+
+out_unregister_proto:
+ proto_unregister(&alg_proto);
+ goto out;
+}
+
+static void __exit af_alg_exit(void)
+{
+ sock_unregister(PF_ALG);
+ proto_unregister(&alg_proto);
+}
+
+module_init(af_alg_init);
+module_exit(af_alg_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(AF_ALG);