[PATCH 16/21] nvme-auth: target: remove obsolete crypto_has_shash() checks

[Eric Biggers]

Since nvme-auth is now doing its HMAC computations using the crypto
library, it's guaranteed that all the algorithms actually work.
Therefore, remove the crypto_has_shash() checks which are now obsolete.

However, the caller in nvmet_auth_negotiate() seems to have also been
relying on crypto_has_shash(nvme_auth_hmac_name(host_hmac_id)) to
validate the host_hmac_id.  Therefore, make it validate the ID more
directly by checking whether nvme_auth_hmac_hash_len() returns 0 or not.

Signed-off-by: Eric Biggers <ebiggers at kernel.org>
---
 drivers/nvme/target/auth.c             | 9 ---------
 drivers/nvme/target/configfs.c         | 3 ---
 drivers/nvme/target/fabrics-cmd-auth.c | 4 +---
 3 files changed, 1 insertion(+), 15 deletions(-)

diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
index f483e1fd48acc..08c1783d70fc4 100644
--- a/drivers/nvme/target/auth.c
+++ b/drivers/nvme/target/auth.c
@@ -43,19 +43,10 @@ int nvmet_auth_set_key(struct nvmet_host *host, const char *secret,
 	if (key_hash > 3) {
 		pr_warn("Invalid DH-HMAC-CHAP hash id %d\n",
 			 key_hash);
 		return -EINVAL;
 	}
-	if (key_hash > 0) {
-		/* Validate selected hash algorithm */
-		const char *hmac = nvme_auth_hmac_name(key_hash);
-
-		if (!crypto_has_shash(hmac, 0, 0)) {
-			pr_err("DH-HMAC-CHAP hash %s unsupported\n", hmac);
-			return -ENOTSUPP;
-		}
-	}
 	dhchap_secret = kstrdup(secret, GFP_KERNEL);
 	if (!dhchap_secret)
 		return -ENOMEM;
 	down_write(&nvmet_config_sem);
 	if (set_ctrl) {
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index 3088e044dbcbb..463348c7f097b 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -15,11 +15,10 @@
 #include <linux/pci-p2pdma.h>
 #ifdef CONFIG_NVME_TARGET_AUTH
 #include <linux/nvme-auth.h>
 #endif
 #include <linux/nvme-keyring.h>
-#include <crypto/hash.h>
 #include <crypto/kpp.h>
 #include <linux/nospec.h>
 
 #include "nvmet.h"
 
@@ -2179,12 +2178,10 @@ static ssize_t nvmet_host_dhchap_hash_store(struct config_item *item,
 	u8 hmac_id;
 
 	hmac_id = nvme_auth_hmac_id(page);
 	if (hmac_id == NVME_AUTH_HASH_INVALID)
 		return -EINVAL;
-	if (!crypto_has_shash(nvme_auth_hmac_name(hmac_id), 0, 0))
-		return -ENOTSUPP;
 	host->dhchap_hash_id = hmac_id;
 	return count;
 }
 
 CONFIGFS_ATTR(nvmet_host_, dhchap_hash);
diff --git a/drivers/nvme/target/fabrics-cmd-auth.c b/drivers/nvme/target/fabrics-cmd-auth.c
index 5946681cb0e32..b703e3bebae4e 100644
--- a/drivers/nvme/target/fabrics-cmd-auth.c
+++ b/drivers/nvme/target/fabrics-cmd-auth.c
@@ -6,11 +6,10 @@
  */
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/blkdev.h>
 #include <linux/random.h>
 #include <linux/nvme-auth.h>
-#include <crypto/hash.h>
 #include <crypto/kpp.h>
 #include "nvmet.h"
 
 static void nvmet_auth_expired_work(struct work_struct *work)
 {
@@ -73,12 +72,11 @@ static u8 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
 
 	for (i = 0; i < data->auth_protocol[0].dhchap.halen; i++) {
 		u8 host_hmac_id = data->auth_protocol[0].dhchap.idlist[i];
 
-		if (!fallback_hash_id &&
-		    crypto_has_shash(nvme_auth_hmac_name(host_hmac_id), 0, 0))
+		if (!fallback_hash_id && nvme_auth_hmac_hash_len(host_hmac_id))
 			fallback_hash_id = host_hmac_id;
 		if (ctrl->shash_id != host_hmac_id)
 			continue;
 		hash_id = ctrl->shash_id;
 		break;
-- 
2.53.0