openssh/kexecdh.c
Damien Miller b3051d01e5 - djm@cvs.openbsd.org 2014/01/09 23:20:00
[digest.c digest.h hostfile.c kex.c kex.h kexc25519.c kexc25519c.c]
     [kexc25519s.c kexdh.c kexecdh.c kexecdhc.c kexecdhs.c kexgex.c kexgexc.c]
     [kexgexs.c key.c key.h roaming_client.c roaming_common.c schnorr.c]
     [schnorr.h ssh-dss.c ssh-ecdsa.c ssh-rsa.c sshconnect2.c]
     Introduce digest API and use it to perform all hashing operations
     rather than calling OpenSSL EVP_Digest* directly. Will make it easier
     to build a reduced-feature OpenSSH without OpenSSL in future;
     feedback, ok markus@
2014-01-10 10:58:53 +11:00

98 lines
3.1 KiB
C

/* $OpenBSD: kexecdh.c,v 1.5 2014/01/09 23:20:00 djm Exp $ */
/*
* Copyright (c) 2001 Markus Friedl. All rights reserved.
* Copyright (c) 2010 Damien Miller. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
#ifdef OPENSSL_HAS_ECC
#include <sys/types.h>
#include <signal.h>
#include <string.h>
#include <openssl/bn.h>
#include <openssl/evp.h>
#include <openssl/ec.h>
#include <openssl/ecdh.h>
#include "buffer.h"
#include "ssh2.h"
#include "key.h"
#include "cipher.h"
#include "kex.h"
#include "log.h"
#include "digest.h"
void
kex_ecdh_hash(
int hash_alg,
const EC_GROUP *ec_group,
char *client_version_string,
char *server_version_string,
char *ckexinit, int ckexinitlen,
char *skexinit, int skexinitlen,
u_char *serverhostkeyblob, int sbloblen,
const EC_POINT *client_dh_pub,
const EC_POINT *server_dh_pub,
const BIGNUM *shared_secret,
u_char **hash, u_int *hashlen)
{
Buffer b;
static u_char digest[SSH_DIGEST_MAX_LENGTH];
buffer_init(&b);
buffer_put_cstring(&b, client_version_string);
buffer_put_cstring(&b, server_version_string);
/* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
buffer_put_int(&b, ckexinitlen+1);
buffer_put_char(&b, SSH2_MSG_KEXINIT);
buffer_append(&b, ckexinit, ckexinitlen);
buffer_put_int(&b, skexinitlen+1);
buffer_put_char(&b, SSH2_MSG_KEXINIT);
buffer_append(&b, skexinit, skexinitlen);
buffer_put_string(&b, serverhostkeyblob, sbloblen);
buffer_put_ecpoint(&b, ec_group, client_dh_pub);
buffer_put_ecpoint(&b, ec_group, server_dh_pub);
buffer_put_bignum2(&b, shared_secret);
#ifdef DEBUG_KEX
buffer_dump(&b);
#endif
if (ssh_digest_buffer(hash_alg, &b, digest, sizeof(digest)) != 0)
fatal("%s: ssh_digest_buffer failed", __func__);
buffer_free(&b);
#ifdef DEBUG_KEX
dump_digest("hash", digest, ssh_digest_bytes(hash_alg));
#endif
*hash = digest;
*hashlen = ssh_digest_bytes(hash_alg);
}
#endif /* OPENSSL_HAS_ECC */