[PATCH 01/17] nvme-keyring: restrict match length for version '1' identifiers

[Hannes Reinecke]

From: Hannes Reinecke <hare at suse.de>

TP8018 changed the TLS PSK identifiers to append a PSK hash value,
so to lookup any version '1' identifiers we need to restrict the
match length to exclude the PSK hash value (which we don't have
when looking up keys).

Signed-off-by: Hannes Reinecke <hare at suse.de>
---
 drivers/nvme/common/keyring.c | 34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)

diff --git a/drivers/nvme/common/keyring.c b/drivers/nvme/common/keyring.c
index 6f7e7a8fa5ae..2beac89b2246 100644
--- a/drivers/nvme/common/keyring.c
+++ b/drivers/nvme/common/keyring.c
@@ -36,14 +36,12 @@ static bool nvme_tls_psk_match(const struct key *key,
 		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;
+	match_len = strlen(match_id);
 	pr_debug("%s: match '%s' '%s' len %zd\n",
 		 __func__, match_id, key->description, match_len);
 	return !memcmp(key->description, match_id, match_len);
@@ -71,7 +69,7 @@ static struct key_type nvme_tls_psk_key_type = {
 
 static struct key *nvme_tls_psk_lookup(struct key *keyring,
 		const char *hostnqn, const char *subnqn,
-		int hmac, bool generated)
+		u8 hmac, u8 psk_ver, bool generated)
 {
 	char *identity;
 	size_t identity_len = (NVMF_NQN_SIZE) * 2 + 11;
@@ -79,11 +77,11 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring,
 	key_serial_t keyring_id;
 
 	identity = kzalloc(identity_len, GFP_KERNEL);
-	if (!identity)
+	if (WARN_ON(!identity))
 		return ERR_PTR(-ENOMEM);
 
-	snprintf(identity, identity_len, "NVMe0%c%02d %s %s",
-		 generated ? 'G' : 'R', hmac, hostnqn, subnqn);
+	snprintf(identity, identity_len, "NVMe%u%c%02u %s %s",
+		 psk_ver, generated ? 'G' : 'R', hmac, hostnqn, subnqn);
 
 	if (!keyring)
 		keyring = nvme_keyring;
@@ -109,19 +107,38 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring,
  *
  * 'Retained' PSKs (ie 'generated == false')
  * should be preferred to 'generated' PSKs,
+ * PSKs with hash (psk_ver 1) should be
+ * preferred to PSKs without (psk_ver 0),
  * and SHA-384 should be preferred to SHA-256.
  */
 static struct nvme_tls_psk_priority_list {
 	bool generated;
+	u8 psk_ver;
 	enum nvme_tcp_tls_cipher cipher;
 } nvme_tls_psk_prio[] = {
 	{ .generated = false,
+	  .psk_ver = 1,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
+	{ .generated = false,
+	  .psk_ver = 1,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
+	{ .generated = false,
+	  .psk_ver = 0,
 	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
 	{ .generated = false,
+	  .psk_ver = 0,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
+	{ .generated = true,
+	  .psk_ver = 1,
+	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
+	{ .generated = true,
+	  .psk_ver = 1,
 	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
 	{ .generated = true,
+	  .psk_ver = 0,
 	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },
 	{ .generated = true,
+	  .psk_ver = 0,
 	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },
 };
 
@@ -137,10 +154,11 @@ key_serial_t nvme_tls_psk_default(struct key *keyring,
 
 	for (prio = 0; prio < ARRAY_SIZE(nvme_tls_psk_prio); prio++) {
 		bool generated = nvme_tls_psk_prio[prio].generated;
+		u8 ver = nvme_tls_psk_prio[prio].psk_ver;
 		enum nvme_tcp_tls_cipher cipher = nvme_tls_psk_prio[prio].cipher;
 
 		tls_key = nvme_tls_psk_lookup(keyring, hostnqn, subnqn,
-					      cipher, generated);
+					      cipher, ver, generated);
 		if (!IS_ERR(tls_key)) {
 			tls_key_id = tls_key->serial;
 			key_put(tls_key);
-- 
2.35.3