nvmet-auth: update sc_c in target host hash calculation

Commit 7e091ad "nvme-auth: update sc_c in host response" added
the sc_c variable to the dhchap queue context structure which is
appropriately set during negotiate and then used in the host response.

This breaks secure concat connections with a Linux target as the target
code wasn't updated at the same time. This patch fixes this by adding a
new sc_c variable to the host hash calculations.

Fixes: 7e091ad ("nvme-auth: update sc_c in host response")
Tested-by: Shin'ichiro Kawasaki <[email protected]>
Tested-by: Yi Zhang <[email protected]>
Reviewed-by: Martin George <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Signed-off-by: Alistair Francis <[email protected]>
Signed-off-by: Keith Busch <[email protected]>

Author: alistair23

drivers/nvme/target/auth.c

@@ -298,7 +298,7 @@ int nvmet_auth_host_hash(struct nvmet_req *req, u8 *response,
 	const char *hash_name;
 	u8 *challenge = req->sq->dhchap_c1;
 	struct nvme_dhchap_key *transformed_key;
-	u8 buf[4], sc_c = ctrl->concat ? 1 : 0;
+	u8 buf[4];
 	int ret;
 
 	hash_name = nvme_auth_hmac_name(ctrl->shash_id);
@@ -367,7 +367,7 @@ int nvmet_auth_host_hash(struct nvmet_req *req, u8 *response,
 	ret = crypto_shash_update(shash, buf, 2);
 	if (ret)
 		goto out;
-	*buf = sc_c;
+	*buf = req->sq->sc_c;
 	ret = crypto_shash_update(shash, buf, 1);
 	if (ret)
 		goto out;

drivers/nvme/target/fabrics-cmd-auth.c

@@ -43,6 +43,7 @@ static u8 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 		 data->auth_protocol[0].dhchap.halen,
 		 data->auth_protocol[0].dhchap.dhlen);
 	req->sq->dhchap_tid = le16_to_cpu(data->t_id);
+	req->sq->sc_c = data->sc_c;
 	if (data->sc_c != NVME_AUTH_SECP_NOSC) {
 		if (!IS_ENABLED(CONFIG_NVME_TARGET_TCP_TLS))
 			return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;

drivers/nvme/target/nvmet.h

@@ -159,6 +159,7 @@ struct nvmet_sq {
 	bool			authenticated;
 	struct delayed_work	auth_expired_work;
 	u16			dhchap_tid;
+	u8			sc_c;
 	u8			dhchap_status;
 	u8			dhchap_step;
 	u8			*dhchap_c1;