diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2017-06-07 22:34:26 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2017-06-19 22:06:28 -0400 |
| commit | 6787ab81b29115b6d2e7d17fe8a8017da66197d6 (patch) | |
| tree | c926aac68602cbf76c6aa121fcacf5902cfc749f /drivers/target/iscsi/iscsi_target_auth.c | |
| parent | 51b0817b0d23d51223575eff14629b3602a93cd4 (diff) | |
| download | linux-6787ab81b29115b6d2e7d17fe8a8017da66197d6.tar.bz2 | |
iscsi: ensure RNG is seeded before use
It's not safe to use weak random data here, especially for the challenge
response randomness. Since we're always in process context, it's safe to
simply wait until we have enough randomness to carry out the
authentication correctly.
While we're at it, we clean up a small memleak during an error
condition.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Chris Leech <cleech@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'drivers/target/iscsi/iscsi_target_auth.c')
| -rw-r--r-- | drivers/target/iscsi/iscsi_target_auth.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c index 903b667f8e01..f9bc8ec6fb6b 100644 --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -47,18 +47,21 @@ static void chap_binaryhex_to_asciihex(char *dst, char *src, int src_len) } } -static void chap_gen_challenge( +static int chap_gen_challenge( struct iscsi_conn *conn, int caller, char *c_str, unsigned int *c_len) { + int ret; unsigned char challenge_asciihex[CHAP_CHALLENGE_LENGTH * 2 + 1]; struct iscsi_chap *chap = conn->auth_protocol; memset(challenge_asciihex, 0, CHAP_CHALLENGE_LENGTH * 2 + 1); - get_random_bytes(chap->challenge, CHAP_CHALLENGE_LENGTH); + ret = get_random_bytes_wait(chap->challenge, CHAP_CHALLENGE_LENGTH); + if (unlikely(ret)) + return ret; chap_binaryhex_to_asciihex(challenge_asciihex, chap->challenge, CHAP_CHALLENGE_LENGTH); /* @@ -69,6 +72,7 @@ static void chap_gen_challenge( pr_debug("[%s] Sending CHAP_C=0x%s\n\n", (caller) ? "server" : "client", challenge_asciihex); + return 0; } static int chap_check_algorithm(const char *a_str) @@ -143,6 +147,7 @@ static struct iscsi_chap *chap_server_open( case CHAP_DIGEST_UNKNOWN: default: pr_err("Unsupported CHAP_A value\n"); + kfree(conn->auth_protocol); return NULL; } @@ -156,7 +161,10 @@ static struct iscsi_chap *chap_server_open( /* * Generate Challenge. */ - chap_gen_challenge(conn, 1, aic_str, aic_len); + if (chap_gen_challenge(conn, 1, aic_str, aic_len) < 0) { + kfree(conn->auth_protocol); + return NULL; + } return chap; } |