2 * Copyright (c) 2001 Markus Friedl. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 RCSID("$OpenBSD: kexdh.c,v 1.20 2005/11/04 05:15:59 djm Exp $");
28 #include <openssl/evp.h>
37 char *client_version_string,
38 char *server_version_string,
39 char *ckexinit, int ckexinitlen,
40 char *skexinit, int skexinitlen,
41 u_char *serverhostkeyblob, int sbloblen,
42 BIGNUM *client_dh_pub,
43 BIGNUM *server_dh_pub,
44 BIGNUM *shared_secret,
45 u_char **hash, u_int *hashlen)
48 static u_char digest[EVP_MAX_MD_SIZE];
49 const EVP_MD *evp_md = EVP_sha1();
53 buffer_put_cstring(&b, client_version_string);
54 buffer_put_cstring(&b, server_version_string);
56 /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
57 buffer_put_int(&b, ckexinitlen+1);
58 buffer_put_char(&b, SSH2_MSG_KEXINIT);
59 buffer_append(&b, ckexinit, ckexinitlen);
60 buffer_put_int(&b, skexinitlen+1);
61 buffer_put_char(&b, SSH2_MSG_KEXINIT);
62 buffer_append(&b, skexinit, skexinitlen);
64 buffer_put_string(&b, serverhostkeyblob, sbloblen);
65 buffer_put_bignum2(&b, client_dh_pub);
66 buffer_put_bignum2(&b, server_dh_pub);
67 buffer_put_bignum2(&b, shared_secret);
72 EVP_DigestInit(&md, evp_md);
73 EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
74 EVP_DigestFinal(&md, digest, NULL);
79 dump_digest("hash", digest, EVP_MD_size(evp_md));
82 *hashlen = EVP_MD_size(evp_md);