scsi: target: iscsi: rename some variables to avoid confusion.

This patch renames some variables in chap_server_compute_hash() to make it
harder to confuse the initiator's challenge with the target's challenge
when the mutual chap authentication is used.

Link: https://lore.kernel.org/r/20191017131037.9903-4-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c
index f3973ab..0e54627 100644 (file)
--- a/drivers/target/iscsi/iscsi_target_auth.c
+++ b/drivers/target/iscsi/iscsi_target_auth.c
@@ -215,8 +215,8 @@ static int chap_server_compute_hash(
        unsigned long id;
        unsigned char id_as_uchar;
        unsigned char type;
-       unsigned char identifier[10], *challenge = NULL;
-       unsigned char *challenge_binhex = NULL;
+       unsigned char identifier[10], *initiatorchg = NULL;
+       unsigned char *initiatorchg_binhex = NULL;
        unsigned char *digest = NULL;
        unsigned char *response = NULL;
        unsigned char *client_digest = NULL;
@@ -226,7 +226,7 @@ static int chap_server_compute_hash(
        struct iscsi_chap *chap = conn->auth_protocol;
        struct crypto_shash *tfm = NULL;
        struct shash_desc *desc = NULL;
-       int auth_ret = -1, ret, challenge_len;
+       int auth_ret = -1, ret, initiatorchg_len;
 
        digest = kzalloc(chap->digest_size, GFP_KERNEL);
        if (!digest) {
@@ -256,15 +256,15 @@ static int chap_server_compute_hash(
        memset(chap_n, 0, MAX_CHAP_N_SIZE);
        memset(chap_r, 0, MAX_RESPONSE_LENGTH);
 
-       challenge = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
-       if (!challenge) {
+       initiatorchg = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
+       if (!initiatorchg) {
                pr_err("Unable to allocate challenge buffer\n");
                goto out;
        }
 
-       challenge_binhex = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
-       if (!challenge_binhex) {
-               pr_err("Unable to allocate challenge_binhex buffer\n");
+       initiatorchg_binhex = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL);
+       if (!initiatorchg_binhex) {
+               pr_err("Unable to allocate initiatorchg_binhex buffer\n");
                goto out;
        }
        /*
@@ -399,7 +399,7 @@ static int chap_server_compute_hash(
         * Get CHAP_C.
         */
        if (extract_param(nr_in_ptr, "CHAP_C", CHAP_CHALLENGE_STR_LEN,
-                       challenge, &type) < 0) {
+                       initiatorchg, &type) < 0) {
                pr_err("Could not find CHAP_C.\n");
                goto out;
        }
@@ -408,28 +408,28 @@ static int chap_server_compute_hash(
                pr_err("Could not find CHAP_C.\n");
                goto out;
        }
-       challenge_len = DIV_ROUND_UP(strlen(challenge), 2);
-       if (!challenge_len) {
+       initiatorchg_len = DIV_ROUND_UP(strlen(initiatorchg), 2);
+       if (!initiatorchg_len) {
                pr_err("Unable to convert incoming challenge\n");
                goto out;
        }
-       if (challenge_len > 1024) {
+       if (initiatorchg_len > 1024) {
                pr_err("CHAP_C exceeds maximum binary size of 1024 bytes\n");
                goto out;
        }
-       if (hex2bin(challenge_binhex, challenge, challenge_len) < 0) {
+       if (hex2bin(initiatorchg_binhex, initiatorchg, initiatorchg_len) < 0) {
                pr_err("Malformed CHAP_C\n");
                goto out;
        }
-       pr_debug("[server] Got CHAP_C=%s\n", challenge);
+       pr_debug("[server] Got CHAP_C=%s\n", initiatorchg);
        /*
         * During mutual authentication, the CHAP_C generated by the
         * initiator must not match the original CHAP_C generated by
         * the target.
         */
-       if (challenge_len == chap->challenge_len &&
-                               !memcmp(challenge_binhex, chap->challenge,
-                               challenge_len)) {
+       if (initiatorchg_len == chap->challenge_len &&
+                               !memcmp(initiatorchg_binhex, chap->challenge,
+                               initiatorchg_len)) {
                pr_err("initiator CHAP_C matches target CHAP_C, failing"
                       " login attempt\n");
                goto out;
@@ -461,7 +461,7 @@ static int chap_server_compute_hash(
        /*
         * Convert received challenge to binary hex.
         */
-       ret = crypto_shash_finup(desc, challenge_binhex, challenge_len,
+       ret = crypto_shash_finup(desc, initiatorchg_binhex, initiatorchg_len,
                                 digest);
        if (ret < 0) {
                pr_err("crypto_shash_finup() failed for ma challenge\n");
@@ -487,8 +487,8 @@ out:
        kzfree(desc);
        if (tfm)
                crypto_free_shash(tfm);
-       kfree(challenge);
-       kfree(challenge_binhex);
+       kfree(initiatorchg);
+       kfree(initiatorchg_binhex);
        kfree(digest);
        kfree(response);
        kfree(server_digest);