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>
This commit is contained in:
Maurizio Lombardi
Martin K. Petersen
parent
f6b8540f40
commit
a572d24af4
@ -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;
|
||||
|
||||
@ -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;
|
||||
|
||||
Loading…
Reference in New Issue
Block a user