4 files changed, 241 insertions, 53 deletions

diff --git a/drivers/nvme/common/Kconfig b/drivers/nvme/common/Kconfig
index 4514f44362..244432e0b7 100644
--- a/drivers/nvme/common/Kconfig
+++ b/drivers/nvme/common/Kconfig
@@ -1,4 +1,14 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-config NVME_COMMON
+config NVME_KEYRING
        tristate
+       select KEYS
+
+config NVME_AUTH
+	tristate
+	select CRYPTO
+	select CRYPTO_HMAC
+	select CRYPTO_SHA256
+	select CRYPTO_SHA512
+	select CRYPTO_DH
+	select CRYPTO_DH_RFC7919_GROUPS
diff --git a/drivers/nvme/common/Makefile b/drivers/nvme/common/Makefile
index 720c625b8a..681514cf2e 100644
--- a/drivers/nvme/common/Makefile
+++ b/drivers/nvme/common/Makefile
@@ -2,6 +2,8 @@
 
 ccflags-y			+= -I$(src)
 
-obj-$(CONFIG_NVME_COMMON)	+= nvme-common.o
+obj-$(CONFIG_NVME_AUTH)		+= nvme-auth.o
+obj-$(CONFIG_NVME_KEYRING)	+= nvme-keyring.o
 
-nvme-common-y			+= auth.o
+nvme-auth-y			+= auth.o
+nvme-keyring-y			+= keyring.o
diff --git a/drivers/nvme/common/auth.c b/drivers/nvme/common/auth.c
index d90e4f0c08..a23ab5c968 100644
--- a/drivers/nvme/common/auth.c
+++ b/drivers/nvme/common/auth.c
@@ -150,6 +150,14 @@ size_t nvme_auth_hmac_hash_len(u8 hmac_id)
 }
 EXPORT_SYMBOL_GPL(nvme_auth_hmac_hash_len);
 
+u32 nvme_auth_key_struct_size(u32 key_len)
+{
+	struct nvme_dhchap_key key;
+
+	return struct_size(&key, key, key_len);
+}
+EXPORT_SYMBOL_GPL(nvme_auth_key_struct_size);
+
 struct nvme_dhchap_key *nvme_auth_extract_key(unsigned char *secret,
 					      u8 key_hash)
 {
@@ -163,14 +171,9 @@ struct nvme_dhchap_key *nvme_auth_extract_key(unsigned char *secret,
 	p = strrchr(secret, ':');
 	if (p)
 		allocated_len = p - secret;
-	key = kzalloc(sizeof(*key), GFP_KERNEL);
+	key = nvme_auth_alloc_key(allocated_len, 0);
 	if (!key)
 		return ERR_PTR(-ENOMEM);
-	key->key = kzalloc(allocated_len, GFP_KERNEL);
-	if (!key->key) {
-		ret = -ENOMEM;
-		goto out_free_key;
-	}
 
 	key_len = base64_decode(secret, allocated_len, key->key);
 	if (key_len < 0) {
@@ -187,14 +190,6 @@ struct nvme_dhchap_key *nvme_auth_extract_key(unsigned char *secret,
 		goto out_free_secret;
 	}
 
-	if (key_hash > 0 &&
-	    (key_len - 4) != nvme_auth_hmac_hash_len(key_hash)) {
-		pr_err("Mismatched key len %d for %s\n", key_len,
-		       nvme_auth_hmac_name(key_hash));
-		ret = -EINVAL;
-		goto out_free_secret;
-	}
-
 	/* The last four bytes is the CRC in little-endian format */
 	key_len -= 4;
 	/*
@@ -213,37 +208,51 @@ struct nvme_dhchap_key *nvme_auth_extract_key(unsigned char *secret,
 	key->hash = key_hash;
 	return key;
 out_free_secret:
-	kfree_sensitive(key->key);
-out_free_key:
-	kfree(key);
+	nvme_auth_free_key(key);
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(nvme_auth_extract_key);
 
+struct nvme_dhchap_key *nvme_auth_alloc_key(u32 len, u8 hash)
+{
+	u32 num_bytes = nvme_auth_key_struct_size(len);
+	struct nvme_dhchap_key *key = kzalloc(num_bytes, GFP_KERNEL);
+
+	if (key) {
+		key->len = len;
+		key->hash = hash;
+	}
+	return key;
+}
+EXPORT_SYMBOL_GPL(nvme_auth_alloc_key);
+
 void nvme_auth_free_key(struct nvme_dhchap_key *key)
 {
 	if (!key)
 		return;
-	kfree_sensitive(key->key);
-	kfree(key);
+	kfree_sensitive(key);
 }
 EXPORT_SYMBOL_GPL(nvme_auth_free_key);
 
-u8 *nvme_auth_transform_key(struct nvme_dhchap_key *key, char *nqn)
+struct nvme_dhchap_key *nvme_auth_transform_key(
+		struct nvme_dhchap_key *key, char *nqn)
 {
 	const char *hmac_name;
 	struct crypto_shash *key_tfm;
 	struct shash_desc *shash;
-	u8 *transformed_key;
-	int ret;
+	struct nvme_dhchap_key *transformed_key;
+	int ret, key_len;
 
-	if (!key || !key->key) {
+	if (!key) {
 		pr_warn("No key specified\n");
 		return ERR_PTR(-ENOKEY);
 	}
 	if (key->hash == 0) {
-		transformed_key = kmemdup(key->key, key->len, GFP_KERNEL);
-		return transformed_key ? transformed_key : ERR_PTR(-ENOMEM);
+		key_len = nvme_auth_key_struct_size(key->len);
+		transformed_key = kmemdup(key, key_len, GFP_KERNEL);
+		if (!transformed_key)
+			return ERR_PTR(-ENOMEM);
+		return transformed_key;
 	}
 	hmac_name = nvme_auth_hmac_name(key->hash);
 	if (!hmac_name) {
@@ -253,7 +262,7 @@ u8 *nvme_auth_transform_key(struct nvme_dhchap_key *key, char *nqn)
 
 	key_tfm = crypto_alloc_shash(hmac_name, 0, 0);
 	if (IS_ERR(key_tfm))
-		return (u8 *)key_tfm;
+		return ERR_CAST(key_tfm);
 
 	shash = kmalloc(sizeof(struct shash_desc) +
 			crypto_shash_descsize(key_tfm),
@@ -263,7 +272,8 @@ u8 *nvme_auth_transform_key(struct nvme_dhchap_key *key, char *nqn)
 		goto out_free_key;
 	}
 
-	transformed_key = kzalloc(crypto_shash_digestsize(key_tfm), GFP_KERNEL);
+	key_len = crypto_shash_digestsize(key_tfm);
+	transformed_key = nvme_auth_alloc_key(key_len, key->hash);
 	if (!transformed_key) {
 		ret = -ENOMEM;
 		goto out_free_shash;
@@ -282,7 +292,7 @@ u8 *nvme_auth_transform_key(struct nvme_dhchap_key *key, char *nqn)
 	ret = crypto_shash_update(shash, "NVMe-over-Fabrics", 17);
 	if (ret < 0)
 		goto out_free_transformed_key;
-	ret = crypto_shash_final(shash, transformed_key);
+	ret = crypto_shash_final(shash, transformed_key->key);
 	if (ret < 0)
 		goto out_free_transformed_key;
 
@@ -292,7 +302,7 @@ u8 *nvme_auth_transform_key(struct nvme_dhchap_key *key, char *nqn)
 	return transformed_key;
 
 out_free_transformed_key:
-	kfree_sensitive(transformed_key);
+	nvme_auth_free_key(transformed_key);
 out_free_shash:
 	kfree(shash);
 out_free_key:
@@ -331,7 +341,6 @@ int nvme_auth_augmented_challenge(u8 hmac_id, u8 *skey, size_t skey_len,
 		u8 *challenge, u8 *aug, size_t hlen)
 {
 	struct crypto_shash *tfm;
-	struct shash_desc *desc;
 	u8 *hashed_key;
 	const char *hmac_name;
 	int ret;
@@ -359,29 +368,11 @@ int nvme_auth_augmented_challenge(u8 hmac_id, u8 *skey, size_t skey_len,
 		goto out_free_key;
 	}
 
-	desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
-		       GFP_KERNEL);
-	if (!desc) {
-		ret = -ENOMEM;
-		goto out_free_hash;
-	}
-	desc->tfm = tfm;
-
 	ret = crypto_shash_setkey(tfm, hashed_key, hlen);
 	if (ret)
-		goto out_free_desc;
-
-	ret = crypto_shash_init(desc);
-	if (ret)
-		goto out_free_desc;
-
-	ret = crypto_shash_update(desc, challenge, hlen);
-	if (ret)
-		goto out_free_desc;
+		goto out_free_hash;
 
-	ret = crypto_shash_final(desc, aug);
-out_free_desc:
-	kfree_sensitive(desc);
+	ret = crypto_shash_tfm_digest(tfm, challenge, hlen, aug);
 out_free_hash:
 	crypto_free_shash(tfm);
 out_free_key:
diff --git a/drivers/nvme/common/keyring.c b/drivers/nvme/common/keyring.c
new file mode 100644
index 0000000000..ee341b83ee
--- /dev/null
+++ b/drivers/nvme/common/keyring.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023 Hannes Reinecke, SUSE Labs
+ */
+
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/key.h>
+#include <linux/key-type.h>
+#include <keys/user-type.h>
+#include <linux/nvme.h>
+#include <linux/nvme-tcp.h>
+#include <linux/nvme-keyring.h>
+
+static struct key *nvme_keyring;
+
+key_serial_t nvme_keyring_id(void)
+{
+	return nvme_keyring->serial;
+}
+EXPORT_SYMBOL_GPL(nvme_keyring_id);
+
+static void nvme_tls_psk_describe(const struct key *key, struct seq_file *m)
+{
+	seq_puts(m, key->description);
+	seq_printf(m, ": %u", key->datalen);
+}
+
+static bool nvme_tls_psk_match(const struct key *key,
+			       const struct key_match_data *match_data)
+{
+	const char *match_id;
+	size_t match_len;
+
+	if (!key->description) {
+		pr_debug("%s: no key description\n", __func__);
+		return false;
+	}
+	match_len = strlen(key->description);
+	pr_debug("%s: id %s len %zd\n", __func__, key->description, match_len);
+
+	if (!match_data->raw_data) {
+		pr_debug("%s: no match data\n", __func__);
+		return false;
+	}
+	match_id = match_data->raw_data;
+	pr_debug("%s: match '%s' '%s' len %zd\n",
+		 __func__, match_id, key->description, match_len);
+	return !memcmp(key->description, match_id, match_len);
+}
+
+static int nvme_tls_psk_match_preparse(struct key_match_data *match_data)
+{
+	match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE;
+	match_data->cmp = nvme_tls_psk_match;
+	return 0;
+}
+
+static struct key_type nvme_tls_psk_key_type = {
+	.name           = "psk",
+	.flags          = KEY_TYPE_NET_DOMAIN,
+	.preparse       = user_preparse,
+	.free_preparse  = user_free_preparse,
+	.match_preparse = nvme_tls_psk_match_preparse,
+	.instantiate    = generic_key_instantiate,
+	.revoke         = user_revoke,
+	.destroy        = user_destroy,
+	.describe       = nvme_tls_psk_describe,
+	.read           = user_read,
+};
+
+static struct key *nvme_tls_psk_lookup(struct key *keyring,
+		const char *hostnqn, const char *subnqn,
+		int hmac, bool generated)
+{
+	char *identity;
+	size_t identity_len = (NVMF_NQN_SIZE) * 2 + 11;
+	key_ref_t keyref;
+	key_serial_t keyring_id;
+
+	identity = kzalloc(identity_len, GFP_KERNEL);
+	if (!identity)
+		return ERR_PTR(-ENOMEM);
+
+	snprintf(identity, identity_len, "NVMe0%c%02d %s %s",
+		 generated ? 'G' : 'R', hmac, hostnqn, subnqn);
+
+	if (!keyring)
+		keyring = nvme_keyring;
+	keyring_id = key_serial(keyring);
+	pr_debug("keyring %x lookup tls psk '%s'\n",
+		 keyring_id, identity);
+	keyref = keyring_search(make_key_ref(keyring, true),
+				&nvme_tls_psk_key_type,
+				identity, false);
+	if (IS_ERR(keyref)) {
+		pr_debug("lookup tls psk '%s' failed, error %ld\n",
+			 identity, PTR_ERR(keyref));
+		kfree(identity);
+		return ERR_PTR(-ENOKEY);
+	}
+	kfree(identity);
+
+	return key_ref_to_ptr(keyref);
+}
+
+/*
+ * NVMe PSK priority list
+ *
+ * 'Retained' PSKs (ie 'generated == false')
+ * should be preferred to 'generated' PSKs,
+ * and SHA-384 should be preferred to SHA-256.
+ */
+struct nvme_tls_psk_priority_list {
+	bool generated;
+	enum nvme_tcp_tls_cipher cipher;
+} nvme_tls_psk_prio[] = {
+	{ .generated = false,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
+	{ .generated = false,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
+	{ .generated = true,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
+	{ .generated = true,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
+};
+
+/*
+ * nvme_tls_psk_default - Return the preferred PSK to use for TLS ClientHello
+ */
+key_serial_t nvme_tls_psk_default(struct key *keyring,
+		      const char *hostnqn, const char *subnqn)
+{
+	struct key *tls_key;
+	key_serial_t tls_key_id;
+	int prio;
+
+	for (prio = 0; prio < ARRAY_SIZE(nvme_tls_psk_prio); prio++) {
+		bool generated = nvme_tls_psk_prio[prio].generated;
+		enum nvme_tcp_tls_cipher cipher = nvme_tls_psk_prio[prio].cipher;
+
+		tls_key = nvme_tls_psk_lookup(keyring, hostnqn, subnqn,
+					      cipher, generated);
+		if (!IS_ERR(tls_key)) {
+			tls_key_id = tls_key->serial;
+			key_put(tls_key);
+			return tls_key_id;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nvme_tls_psk_default);
+
+static int __init nvme_keyring_init(void)
+{
+	int err;
+
+	nvme_keyring = keyring_alloc(".nvme",
+				     GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
+				     current_cred(),
+				     (KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				     (KEY_USR_ALL & ~KEY_USR_SETATTR),
+				     KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
+	if (IS_ERR(nvme_keyring))
+		return PTR_ERR(nvme_keyring);
+
+	err = register_key_type(&nvme_tls_psk_key_type);
+	if (err) {
+		key_put(nvme_keyring);
+		return err;
+	}
+	return 0;
+}
+
+static void __exit nvme_keyring_exit(void)
+{
+	unregister_key_type(&nvme_tls_psk_key_type);
+	key_revoke(nvme_keyring);
+	key_put(nvme_keyring);
+}
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>");
+module_init(nvme_keyring_init);
+module_exit(nvme_keyring_exit);