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author | Maurizio Lombardi <mlombard@redhat.com> | 2019-10-28 13:38:20 +0100 |
---|---|---|
committer | Martin K. Petersen <martin.petersen@oracle.com> | 2019-11-06 00:11:35 -0500 |
commit | a572d24af4d16e70743feb0b4decb17aaae7ce43 (patch) | |
tree | a0a91f8f6724047553110c4c427c9ceb42133a29 | |
parent | f6b8540f40201bff91062dd64db8e29e4ddaaa9d (diff) | |
download | linux-a572d24af4d16e70743feb0b4decb17aaae7ce43.tar.gz linux-a572d24af4d16e70743feb0b4decb17aaae7ce43.tar.bz2 linux-a572d24af4d16e70743feb0b4decb17aaae7ce43.zip |
scsi: target: iscsi: CHAP: add support for SHA1, SHA256 and SHA3-256
This patch modifies the chap_server_compute_hash() function to make it
agnostic to the choice of hash algorithm that is used. It also adds
support to three new hash algorithms: SHA1, SHA256 and SHA3-256.
The chap_got_response() function has been removed because the digest type
validity is already checked by chap_server_open()
Link: https://lore.kernel.org/r/20191028123822.5864-2-mlombard@redhat.com
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Tested-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
-rw-r--r-- | drivers/target/iscsi/iscsi_target_auth.c | 169 | ||||
-rw-r--r-- | drivers/target/iscsi/iscsi_target_auth.h | 13 |
2 files changed, 120 insertions, 62 deletions
diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c index 8fe9b12a07a4..b09f20842e40 100644 --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -18,6 +18,22 @@ #include "iscsi_target_nego.h" #include "iscsi_target_auth.h" +static char *chap_get_digest_name(const int digest_type) +{ + switch (digest_type) { + case CHAP_DIGEST_MD5: + return "md5"; + case CHAP_DIGEST_SHA1: + return "sha1"; + case CHAP_DIGEST_SHA256: + return "sha256"; + case CHAP_DIGEST_SHA3_256: + return "sha3-256"; + default: + return NULL; + } +} + static int chap_gen_challenge( struct iscsi_conn *conn, int caller, @@ -46,9 +62,23 @@ static int chap_gen_challenge( return 0; } +static int chap_test_algorithm(const char *name) +{ + struct crypto_shash *tfm; + + tfm = crypto_alloc_shash(name, 0, 0); + if (IS_ERR(tfm)) + return -1; + + crypto_free_shash(tfm); + return 0; +} + static int chap_check_algorithm(const char *a_str) { - char *tmp, *orig, *token; + char *tmp, *orig, *token, *digest_name; + long digest_type; + int r = CHAP_DIGEST_UNKNOWN; tmp = kstrdup(a_str, GFP_KERNEL); if (!tmp) { @@ -70,15 +100,24 @@ static int chap_check_algorithm(const char *a_str) if (!token) goto out; - if (!strcmp(token, "5")) { - pr_debug("Selected MD5 Algorithm\n"); - kfree(orig); - return CHAP_DIGEST_MD5; + if (kstrtol(token, 10, &digest_type)) + continue; + + digest_name = chap_get_digest_name(digest_type); + if (!digest_name) + continue; + + pr_debug("Selected %s Algorithm\n", digest_name); + if (chap_test_algorithm(digest_name) < 0) { + pr_err("failed to allocate %s algo\n", digest_name); + } else { + r = digest_type; + goto out; } } out: kfree(orig); - return CHAP_DIGEST_UNKNOWN; + return r; } static void chap_close(struct iscsi_conn *conn) @@ -94,7 +133,7 @@ static struct iscsi_chap *chap_server_open( char *aic_str, unsigned int *aic_len) { - int ret; + int digest_type; struct iscsi_chap *chap; if (!(auth->naf_flags & NAF_USERID_SET) || @@ -109,17 +148,19 @@ static struct iscsi_chap *chap_server_open( return NULL; chap = conn->auth_protocol; - ret = chap_check_algorithm(a_str); - switch (ret) { + digest_type = chap_check_algorithm(a_str); + switch (digest_type) { case CHAP_DIGEST_MD5: - pr_debug("[server] Got CHAP_A=5\n"); - /* - * Send back CHAP_A set to MD5. - */ - *aic_len = sprintf(aic_str, "CHAP_A=5"); - *aic_len += 1; - chap->digest_type = CHAP_DIGEST_MD5; - pr_debug("[server] Sending CHAP_A=%d\n", chap->digest_type); + chap->digest_size = MD5_SIGNATURE_SIZE; + break; + case CHAP_DIGEST_SHA1: + chap->digest_size = SHA1_SIGNATURE_SIZE; + break; + case CHAP_DIGEST_SHA256: + chap->digest_size = SHA256_SIGNATURE_SIZE; + break; + case CHAP_DIGEST_SHA3_256: + chap->digest_size = SHA3_256_SIGNATURE_SIZE; break; case CHAP_DIGEST_UNKNOWN: default: @@ -128,6 +169,13 @@ static struct iscsi_chap *chap_server_open( return NULL; } + chap->digest_name = chap_get_digest_name(digest_type); + + pr_debug("[server] Got CHAP_A=%d\n", digest_type); + *aic_len = sprintf(aic_str, "CHAP_A=%d", digest_type); + *aic_len += 1; + pr_debug("[server] Sending CHAP_A=%d\n", digest_type); + /* * Set Identifier. */ @@ -146,7 +194,7 @@ static struct iscsi_chap *chap_server_open( return chap; } -static int chap_server_compute_md5( +static int chap_server_compute_hash( struct iscsi_conn *conn, struct iscsi_node_auth *auth, char *nr_in_ptr, @@ -155,12 +203,13 @@ static int chap_server_compute_md5( { unsigned long id; unsigned char id_as_uchar; - unsigned char digest[MD5_SIGNATURE_SIZE]; - unsigned char type, response[MD5_SIGNATURE_SIZE * 2 + 2]; + unsigned char type; unsigned char identifier[10], *challenge = NULL; unsigned char *challenge_binhex = NULL; - unsigned char client_digest[MD5_SIGNATURE_SIZE]; - unsigned char server_digest[MD5_SIGNATURE_SIZE]; + unsigned char *digest = NULL; + unsigned char *response = NULL; + unsigned char *client_digest = NULL; + unsigned char *server_digest = NULL; unsigned char chap_n[MAX_CHAP_N_SIZE], chap_r[MAX_RESPONSE_LENGTH]; size_t compare_len; struct iscsi_chap *chap = conn->auth_protocol; @@ -168,13 +217,33 @@ static int chap_server_compute_md5( struct shash_desc *desc = NULL; int auth_ret = -1, ret, challenge_len; + digest = kzalloc(chap->digest_size, GFP_KERNEL); + if (!digest) { + pr_err("Unable to allocate the digest buffer\n"); + goto out; + } + + response = kzalloc(chap->digest_size * 2 + 2, GFP_KERNEL); + if (!response) { + pr_err("Unable to allocate the response buffer\n"); + goto out; + } + + client_digest = kzalloc(chap->digest_size, GFP_KERNEL); + if (!client_digest) { + pr_err("Unable to allocate the client_digest buffer\n"); + goto out; + } + + server_digest = kzalloc(chap->digest_size, GFP_KERNEL); + if (!server_digest) { + pr_err("Unable to allocate the server_digest buffer\n"); + goto out; + } + memset(identifier, 0, 10); memset(chap_n, 0, MAX_CHAP_N_SIZE); memset(chap_r, 0, MAX_RESPONSE_LENGTH); - memset(digest, 0, MD5_SIGNATURE_SIZE); - memset(response, 0, MD5_SIGNATURE_SIZE * 2 + 2); - memset(client_digest, 0, MD5_SIGNATURE_SIZE); - memset(server_digest, 0, MD5_SIGNATURE_SIZE); challenge = kzalloc(CHAP_CHALLENGE_STR_LEN, GFP_KERNEL); if (!challenge) { @@ -219,18 +288,18 @@ static int chap_server_compute_md5( pr_err("Could not find CHAP_R.\n"); goto out; } - if (strlen(chap_r) != MD5_SIGNATURE_SIZE * 2) { + if (strlen(chap_r) != chap->digest_size * 2) { pr_err("Malformed CHAP_R\n"); goto out; } - if (hex2bin(client_digest, chap_r, MD5_SIGNATURE_SIZE) < 0) { + if (hex2bin(client_digest, chap_r, chap->digest_size) < 0) { pr_err("Malformed CHAP_R\n"); goto out; } pr_debug("[server] Got CHAP_R=%s\n", chap_r); - tfm = crypto_alloc_shash("md5", 0, 0); + tfm = crypto_alloc_shash(chap->digest_name, 0, 0); if (IS_ERR(tfm)) { tfm = NULL; pr_err("Unable to allocate struct crypto_shash\n"); @@ -271,15 +340,15 @@ static int chap_server_compute_md5( goto out; } - bin2hex(response, server_digest, MD5_SIGNATURE_SIZE); - pr_debug("[server] MD5 Server Digest: %s\n", response); + bin2hex(response, server_digest, chap->digest_size); + pr_debug("[server] %s Server Digest: %s\n", hash_name, response); - if (memcmp(server_digest, client_digest, MD5_SIGNATURE_SIZE) != 0) { - pr_debug("[server] MD5 Digests do not match!\n\n"); + if (memcmp(server_digest, client_digest, chap->digest_size) != 0) { + pr_debug("[server] %s Digests do not match!\n\n", hash_name); goto out; } else - pr_debug("[server] MD5 Digests match, CHAP connection" - " successful.\n\n"); + pr_debug("[server] %s Digests match, CHAP connection" + " successful.\n\n", hash_name); /* * One way authentication has succeeded, return now if mutual * authentication is not enabled. @@ -393,7 +462,7 @@ static int chap_server_compute_md5( /* * Convert response from binary hex to ascii hext. */ - bin2hex(response, digest, MD5_SIGNATURE_SIZE); + bin2hex(response, digest, chap->digest_size); *nr_out_len += sprintf(nr_out_ptr + *nr_out_len, "CHAP_R=0x%s", response); *nr_out_len += 1; @@ -405,31 +474,13 @@ out: crypto_free_shash(tfm); kfree(challenge); kfree(challenge_binhex); + kfree(digest); + kfree(response); + kfree(server_digest); + kfree(client_digest); return auth_ret; } -static int chap_got_response( - struct iscsi_conn *conn, - struct iscsi_node_auth *auth, - char *nr_in_ptr, - char *nr_out_ptr, - unsigned int *nr_out_len) -{ - struct iscsi_chap *chap = conn->auth_protocol; - - switch (chap->digest_type) { - case CHAP_DIGEST_MD5: - if (chap_server_compute_md5(conn, auth, nr_in_ptr, - nr_out_ptr, nr_out_len) < 0) - return -1; - return 0; - default: - pr_err("Unknown CHAP digest type %d!\n", - chap->digest_type); - return -1; - } -} - u32 chap_main_loop( struct iscsi_conn *conn, struct iscsi_node_auth *auth, @@ -448,7 +499,7 @@ u32 chap_main_loop( return 0; } else if (chap->chap_state == CHAP_STAGE_SERVER_AIC) { convert_null_to_semi(in_text, *in_len); - if (chap_got_response(conn, auth, in_text, out_text, + if (chap_server_compute_hash(conn, auth, in_text, out_text, out_len) < 0) { chap_close(conn); return 2; diff --git a/drivers/target/iscsi/iscsi_target_auth.h b/drivers/target/iscsi/iscsi_target_auth.h index d5600ac30b53..93db1ab5516c 100644 --- a/drivers/target/iscsi/iscsi_target_auth.h +++ b/drivers/target/iscsi/iscsi_target_auth.h @@ -6,14 +6,19 @@ #define CHAP_DIGEST_UNKNOWN 0 #define CHAP_DIGEST_MD5 5 -#define CHAP_DIGEST_SHA 6 +#define CHAP_DIGEST_SHA1 6 +#define CHAP_DIGEST_SHA256 7 +#define CHAP_DIGEST_SHA3_256 8 #define CHAP_CHALLENGE_LENGTH 16 #define CHAP_CHALLENGE_STR_LEN 4096 -#define MAX_RESPONSE_LENGTH 64 /* sufficient for MD5 */ +#define MAX_RESPONSE_LENGTH 128 /* sufficient for SHA3 256 */ #define MAX_CHAP_N_SIZE 512 #define MD5_SIGNATURE_SIZE 16 /* 16 bytes in a MD5 message digest */ +#define SHA1_SIGNATURE_SIZE 20 /* 20 bytes in a SHA1 message digest */ +#define SHA256_SIGNATURE_SIZE 32 /* 32 bytes in a SHA256 message digest */ +#define SHA3_256_SIGNATURE_SIZE 32 /* 32 bytes in a SHA3 256 message digest */ #define CHAP_STAGE_CLIENT_A 1 #define CHAP_STAGE_SERVER_AIC 2 @@ -28,9 +33,11 @@ extern u32 chap_main_loop(struct iscsi_conn *, struct iscsi_node_auth *, char *, int *, int *); struct iscsi_chap { - unsigned char digest_type; unsigned char id; unsigned char challenge[CHAP_CHALLENGE_LENGTH]; + unsigned int challenge_len; + unsigned char *digest_name; + unsigned int digest_size; unsigned int authenticate_target; unsigned int chap_state; } ____cacheline_aligned; |