[PATCH 05/10] nvme-keyring: add nvme_tls_psk_refresh()

Hannes Reinecke
2024-12-03T11:15:03Z

Add a function to refresh a generated PSK in the specified keyring.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
drivers/nvme/common/keyring.c | 64 +++++++++++++++++++++++++++++++++++
include/linux/nvme-keyring.h | 10 +++++-
2 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/common/keyring.c b/drivers/nvme/common/keyring.c
index ed5167f942d8..8cb253fcd586 100644
--- a/drivers/nvme/common/keyring.c
+++ b/drivers/nvme/common/keyring.c
@@ -124,6 +124,70 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring,
return key_ref_to_ptr(keyref);
}

+/**
+ * nvme_tls_psk_refresh - Refresh TLS PSK
+ * @keyring: Keyring holding the TLS PSK
+ * @hostnqn: Host NQN to use
+ * @subnqn: Subsystem NQN to use
+ * @hmac_id: Hash function identifier
+ * @data: TLS PSK key material
+ * @data_len: Length of @data
+ * @digest: TLS PSK digest
+ *
+ * Refresh a generated version 1 TLS PSK with the identity generated
+ * from @hmac_id, @hostnqn, @subnqn, and @digest in the keyring given
+ * by @keyring.
+ *
+ * Returns the updated key success or an error pointer otherwise.
+ */
+struct key *nvme_tls_psk_refresh(struct key *keyring,
+ const char *hostnqn, const char *subnqn, u8 hmac_id,
+ u8 *data, size_t data_len, const char *digest)
+{
+ key_perm_t keyperm =
+ KEY_POS_SEARCH | KEY_POS_VIEW | KEY_POS_READ |
+ KEY_POS_WRITE | KEY_POS_LINK | KEY_POS_SETATTR |
+ KEY_USR_SEARCH | KEY_USR_VIEW | KEY_USR_READ;
+ char *identity;
+ key_ref_t keyref;
+ key_serial_t keyring_id;
+ struct key *key;
+
+ if (!hostnqn || !subnqn || !data || !data_len)
+ return ERR_PTR(-EINVAL);
+
+ identity = kasprintf(GFP_KERNEL, "NVMe1G%02d %s %s %s",
+ hmac_id, hostnqn, subnqn, digest);
+ if (!identity)
+ return ERR_PTR(-ENOMEM);
+
+ if (!keyring)
+ keyring = nvme_keyring;
+ keyring_id = key_serial(keyring);
+ pr_debug("keyring %x refresh tls psk '%s'\n",
+ keyring_id, identity);
+ keyref = key_create_or_update(make_key_ref(keyring, true),
+ "psk", identity, data, data_len,
+ keyperm, KEY_ALLOC_NOT_IN_QUOTA |
+ KEY_ALLOC_BUILT_IN |
+ KEY_ALLOC_BYPASS_RESTRICTION);
+ if (IS_ERR(keyref)) {
+ pr_debug("refresh tls psk '%s' failed, error %ld\n",
+ identity, PTR_ERR(keyref));
+ kfree(identity);
+ return ERR_PTR(-ENOKEY);
+ }
+ kfree(identity);
+ /*
+ * Set the default timeout to 1 hour
+ * as suggested in TP8018.
+ */
+ key = key_ref_to_ptr(keyref);
+ key_set_timeout(key, 3600);
+ return key;
+}
+EXPORT_SYMBOL_GPL(nvme_tls_psk_refresh);
+
/*
* NVMe PSK priority list
*
diff --git a/include/linux/nvme-keyring.h b/include/linux/nvme-keyring.h
index 19d2b256180f..f7bbcbeb4b13 100644
--- a/include/linux/nvme-keyring.h
+++ b/include/linux/nvme-keyring.h
@@ -8,13 +8,21 @@

#if IS_ENABLED(CONFIG_NVME_KEYRING)

+struct key *nvme_tls_psk_refresh(struct key *keyring,
+ const char *hostnqn, const char *subnqn, u8 hmac_id,
+ u8 *data, size_t data_len, const char *digest);
key_serial_t nvme_tls_psk_default(struct key *keyring,
const char *hostnqn, const char *subnqn);

key_serial_t nvme_keyring_id(void);
struct key *nvme_tls_key_lookup(key_serial_t key_id);
#else
-
+static inline struct key *nvme_tls_psk_refresh(struct key *keyring,
+ const char *hostnqn, char *subnqn, u8 hmac_id,
+ u8 *data, size_t data_len, const char *digest)
+{
+ return ERR_PTR(-ENOTSUPP);
+}
static inline key_serial_t nvme_tls_psk_default(struct key *keyring,
const char *hostnqn, const char *subnqn)
{
--
2.35.3