diff options
author | djm@openbsd.org <djm@openbsd.org> | 2015-01-30 00:22:25 +0000 |
---|---|---|
committer | Damien Miller <djm@mindrot.org> | 2015-01-30 12:16:33 +1100 |
commit | 25f5f78d8bf5c22d9cea8b49de24ebeee648a355 (patch) | |
tree | 5ce84c180ed0769333a62335bd1d10d785f190b8 /kex.c | |
parent | 9ce86c926dfa6e0635161b035e3944e611cbccf0 (diff) |
upstream commit
fix ssh protocol 1, spotted by miod@
Diffstat (limited to 'kex.c')
-rw-r--r-- | kex.c | 29 |
1 files changed, 20 insertions, 9 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: kex.c,v 1.104 2015/01/26 06:10:03 djm Exp $ */ +/* $OpenBSD: kex.c,v 1.105 2015/01/30 00:22:25 djm Exp $ */ /* * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. * @@ -785,17 +785,27 @@ int derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus, u_int8_t cookie[8], u_int8_t id[16]) { - u_int8_t nbuf[2048], obuf[SSH_DIGEST_MAX_LENGTH]; + u_int8_t hbuf[2048], sbuf[2048], obuf[SSH_DIGEST_MAX_LENGTH]; struct ssh_digest_ctx *hashctx = NULL; - size_t len; + size_t hlen, slen; int r; - len = BN_num_bytes(host_modulus); - if (len < (512 / 8) || (u_int)len > sizeof(nbuf)) + hlen = BN_num_bytes(host_modulus); + slen = BN_num_bytes(server_modulus); + if (hlen < (512 / 8) || (u_int)hlen > sizeof(hbuf) || + slen < (512 / 8) || (u_int)slen > sizeof(sbuf)) return SSH_ERR_KEY_BITS_MISMATCH; - if (BN_bn2bin(host_modulus, nbuf) <= 0 || - (hashctx = ssh_digest_start(SSH_DIGEST_MD5)) == NULL || - ssh_digest_update(hashctx, nbuf, len) != 0 || + if (BN_bn2bin(host_modulus, hbuf) <= 0 || + BN_bn2bin(server_modulus, sbuf) <= 0) { + r = SSH_ERR_LIBCRYPTO_ERROR; + goto out; + } + if ((hashctx = ssh_digest_start(SSH_DIGEST_MD5)) == NULL) { + r = SSH_ERR_ALLOC_FAIL; + goto out; + } + if (ssh_digest_update(hashctx, hbuf, hlen) != 0 || + ssh_digest_update(hashctx, sbuf, slen) != 0 || ssh_digest_update(hashctx, cookie, 8) != 0 || ssh_digest_final(hashctx, obuf, sizeof(obuf)) != 0) { r = SSH_ERR_LIBCRYPTO_ERROR; @@ -805,7 +815,8 @@ derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus, r = 0; out: ssh_digest_free(hashctx); - explicit_bzero(nbuf, sizeof(nbuf)); + explicit_bzero(hbuf, sizeof(hbuf)); + explicit_bzero(sbuf, sizeof(sbuf)); explicit_bzero(obuf, sizeof(obuf)); return r; } |