Branch data     Line data    Source code

       1                 :            : /* $OpenBSD: kexdh.c,v 1.24 2014/01/09 23:20:00 djm Exp $ */
       2                 :            : /*
       3                 :            :  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
       4                 :            :  *
       5                 :            :  * Redistribution and use in source and binary forms, with or without
       6                 :            :  * modification, are permitted provided that the following conditions
       7                 :            :  * are met:
       8                 :            :  * 1. Redistributions of source code must retain the above copyright
       9                 :            :  *    notice, this list of conditions and the following disclaimer.
      10                 :            :  * 2. Redistributions in binary form must reproduce the above copyright
      11                 :            :  *    notice, this list of conditions and the following disclaimer in the
      12                 :            :  *    documentation and/or other materials provided with the distribution.
      13                 :            :  *
      14                 :            :  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
      15                 :            :  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
      16                 :            :  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
      17                 :            :  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
      18                 :            :  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
      19                 :            :  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      20                 :            :  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      21                 :            :  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      22                 :            :  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
      23                 :            :  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      24                 :            :  */
      25                 :            : 
      26                 :            : #include "includes.h"
      27                 :            : 
      28                 :            : #include <sys/types.h>
      29                 :            : 
      30                 :            : #include <signal.h>
      31                 :            : 
      32                 :            : #include <openssl/evp.h>
      33                 :            : 
      34                 :            : #include "buffer.h"
      35                 :            : #include "ssh2.h"
      36                 :            : #include "key.h"
      37                 :            : #include "cipher.h"
      38                 :            : #include "kex.h"
      39                 :            : #include "digest.h"
      40                 :            : #include "log.h"
      41                 :            : 
      42                 :            : void
      43                 :        103 : kex_dh_hash(
      44                 :            :     char *client_version_string,
      45                 :            :     char *server_version_string,
      46                 :            :     char *ckexinit, int ckexinitlen,
      47                 :            :     char *skexinit, int skexinitlen,
      48                 :            :     u_char *serverhostkeyblob, int sbloblen,
      49                 :            :     BIGNUM *client_dh_pub,
      50                 :            :     BIGNUM *server_dh_pub,
      51                 :            :     BIGNUM *shared_secret,
      52                 :            :     u_char **hash, u_int *hashlen)
      53                 :            : {
      54                 :            :         Buffer b;
      55                 :            :         static u_char digest[SSH_DIGEST_MAX_LENGTH];
      56                 :            : 
      57                 :        103 :         buffer_init(&b);
      58                 :        103 :         buffer_put_cstring(&b, client_version_string);
      59                 :        103 :         buffer_put_cstring(&b, server_version_string);
      60                 :            : 
      61                 :            :         /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
      62                 :        103 :         buffer_put_int(&b, ckexinitlen+1);
      63                 :        103 :         buffer_put_char(&b, SSH2_MSG_KEXINIT);
      64                 :        103 :         buffer_append(&b, ckexinit, ckexinitlen);
      65                 :        103 :         buffer_put_int(&b, skexinitlen+1);
      66                 :        103 :         buffer_put_char(&b, SSH2_MSG_KEXINIT);
      67                 :        103 :         buffer_append(&b, skexinit, skexinitlen);
      68                 :            : 
      69                 :        103 :         buffer_put_string(&b, serverhostkeyblob, sbloblen);
      70                 :        103 :         buffer_put_bignum2(&b, client_dh_pub);
      71                 :        103 :         buffer_put_bignum2(&b, server_dh_pub);
      72                 :        103 :         buffer_put_bignum2(&b, shared_secret);
      73                 :            : 
      74                 :            : #ifdef DEBUG_KEX
      75                 :            :         buffer_dump(&b);
      76                 :            : #endif
      77         [ -  + ]:        103 :         if (ssh_digest_buffer(SSH_DIGEST_SHA1, &b, digest, sizeof(digest)) != 0)
      78                 :          0 :                 fatal("%s: ssh_digest_buffer failed", __func__);
      79                 :            : 
      80                 :        103 :         buffer_free(&b);
      81                 :            : 
      82                 :            : #ifdef DEBUG_KEX
      83                 :            :         dump_digest("hash", digest, ssh_digest_bytes(SSH_DIGEST_SHA1));
      84                 :            : #endif
      85                 :        103 :         *hash = digest;
      86                 :        103 :         *hashlen = ssh_digest_bytes(SSH_DIGEST_SHA1);
      87                 :        103 : }