djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 1 | /* $OpenBSD: kexecdh.c,v 1.7 2018/12/27 03:25:25 djm Exp $ */ |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (c) 2001 Markus Friedl. All rights reserved. |
| 4 | * Copyright (c) 2010 Damien Miller. All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions |
| 8 | * are met: |
| 9 | * 1. Redistributions of source code must retain the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer. |
| 11 | * 2. Redistributions in binary form must reproduce the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer in the |
| 13 | * documentation and/or other materials provided with the distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | |
Damien Miller | c79ff07 | 2010-08-31 22:50:48 +1000 | [diff] [blame] | 27 | #include "includes.h" |
| 28 | |
Damien Miller | 72ef7c1 | 2015-01-15 02:21:31 +1100 | [diff] [blame] | 29 | #if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC) |
Damien Miller | 6af914a | 2010-09-10 11:39:26 +1000 | [diff] [blame] | 30 | |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 31 | #include <sys/types.h> |
| 32 | |
| 33 | #include <signal.h> |
| 34 | #include <string.h> |
| 35 | |
| 36 | #include <openssl/bn.h> |
| 37 | #include <openssl/evp.h> |
| 38 | #include <openssl/ec.h> |
| 39 | #include <openssl/ecdh.h> |
| 40 | |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 41 | #include "ssh2.h" |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 42 | #include "sshkey.h" |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 43 | #include "cipher.h" |
| 44 | #include "kex.h" |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 45 | #include "sshbuf.h" |
Damien Miller | b3051d0 | 2014-01-10 10:58:53 +1100 | [diff] [blame] | 46 | #include "digest.h" |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 47 | #include "ssherr.h" |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 48 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 49 | int |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 50 | kex_ecdh_hash( |
Damien Miller | b3051d0 | 2014-01-10 10:58:53 +1100 | [diff] [blame] | 51 | int hash_alg, |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 52 | const EC_GROUP *ec_group, |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 53 | const struct sshbuf *client_version, |
| 54 | const struct sshbuf *server_version, |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 55 | const u_char *ckexinit, size_t ckexinitlen, |
| 56 | const u_char *skexinit, size_t skexinitlen, |
| 57 | const u_char *serverhostkeyblob, size_t sbloblen, |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 58 | const EC_POINT *client_dh_pub, |
| 59 | const EC_POINT *server_dh_pub, |
| 60 | const BIGNUM *shared_secret, |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 61 | u_char *hash, size_t *hashlen) |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 62 | { |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 63 | struct sshbuf *b; |
| 64 | int r; |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 65 | |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 66 | if (*hashlen < ssh_digest_bytes(hash_alg)) |
| 67 | return SSH_ERR_INVALID_ARGUMENT; |
| 68 | if ((b = sshbuf_new()) == NULL) |
| 69 | return SSH_ERR_ALLOC_FAIL; |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 70 | if ((r = sshbuf_put_stringb(b, client_version)) < 0 || |
| 71 | (r = sshbuf_put_stringb(b, server_version)) < 0 || |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 72 | /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */ |
| 73 | (r = sshbuf_put_u32(b, ckexinitlen+1)) != 0 || |
| 74 | (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 || |
| 75 | (r = sshbuf_put(b, ckexinit, ckexinitlen)) != 0 || |
| 76 | (r = sshbuf_put_u32(b, skexinitlen+1)) != 0 || |
| 77 | (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 || |
| 78 | (r = sshbuf_put(b, skexinit, skexinitlen)) != 0 || |
| 79 | (r = sshbuf_put_string(b, serverhostkeyblob, sbloblen)) != 0 || |
| 80 | (r = sshbuf_put_ec(b, client_dh_pub, ec_group)) != 0 || |
| 81 | (r = sshbuf_put_ec(b, server_dh_pub, ec_group)) != 0 || |
| 82 | (r = sshbuf_put_bignum2(b, shared_secret)) != 0) { |
| 83 | sshbuf_free(b); |
| 84 | return r; |
| 85 | } |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 86 | #ifdef DEBUG_KEX |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 87 | sshbuf_dump(b, stderr); |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 88 | #endif |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 89 | if (ssh_digest_buffer(hash_alg, b, hash, *hashlen) != 0) { |
| 90 | sshbuf_free(b); |
| 91 | return SSH_ERR_LIBCRYPTO_ERROR; |
| 92 | } |
| 93 | sshbuf_free(b); |
Damien Miller | b3051d0 | 2014-01-10 10:58:53 +1100 | [diff] [blame] | 94 | *hashlen = ssh_digest_bytes(hash_alg); |
markus@openbsd.org | 57d10cb | 2015-01-19 20:16:15 +0000 | [diff] [blame] | 95 | #ifdef DEBUG_KEX |
| 96 | dump_digest("hash", hash, *hashlen); |
| 97 | #endif |
| 98 | return 0; |
Damien Miller | eb8b60e | 2010-08-31 22:41:14 +1000 | [diff] [blame] | 99 | } |
Damien Miller | 72ef7c1 | 2015-01-15 02:21:31 +1100 | [diff] [blame] | 100 | #endif /* defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC) */ |