Return to kexecdh.c CVS log

Up to [local] / src / usr.bin / ssh

Annotation of src/usr.bin/ssh/kexecdh.c, Revision 1.6

1.6     ! markus      1: /* $OpenBSD: kexecdh.c,v 1.5 2014/01/09 23:20:00 djm Exp $ */
1.1       djm         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:
                     27: #include <sys/types.h>
                     28:
                     29: #include <signal.h>
                     30: #include <string.h>
                     31:
                     32: #include <openssl/bn.h>
                     33: #include <openssl/evp.h>
                     34: #include <openssl/ec.h>
                     35: #include <openssl/ecdh.h>
                     36:
                     37: #include "ssh2.h"
1.6     ! markus     38: #include "sshkey.h"
1.1       djm        39: #include "cipher.h"
                     40: #include "kex.h"
1.6     ! markus     41: #include "sshbuf.h"
1.5       djm        42: #include "digest.h"
1.6     ! markus     43: #include "ssherr.h"
1.1       djm        44:
1.6     ! markus     45: int
1.1       djm        46: kex_ecdh_hash(
1.5       djm        47:     int hash_alg,
1.1       djm        48:     const EC_GROUP *ec_group,
1.6     ! markus     49:     const char *client_version_string,
        !            50:     const char *server_version_string,
        !            51:     const u_char *ckexinit, size_t ckexinitlen,
        !            52:     const u_char *skexinit, size_t skexinitlen,
        !            53:     const u_char *serverhostkeyblob, size_t sbloblen,
1.1       djm        54:     const EC_POINT *client_dh_pub,
                     55:     const EC_POINT *server_dh_pub,
                     56:     const BIGNUM *shared_secret,
1.6     ! markus     57:     u_char *hash, size_t *hashlen)
1.1       djm        58: {
1.6     ! markus     59:        struct sshbuf *b;
        !            60:        int r;
1.1       djm        61:
1.6     ! markus     62:        if (*hashlen < ssh_digest_bytes(hash_alg))
        !            63:                return SSH_ERR_INVALID_ARGUMENT;
        !            64:        if ((b = sshbuf_new()) == NULL)
        !            65:                return SSH_ERR_ALLOC_FAIL;
        !            66:        if ((r = sshbuf_put_cstring(b, client_version_string)) != 0 ||
        !            67:            (r = sshbuf_put_cstring(b, server_version_string)) != 0 ||
        !            68:            /* kexinit messages: fake header: len+SSH2_MSG_KEXINIT */
        !            69:            (r = sshbuf_put_u32(b, ckexinitlen+1)) != 0 ||
        !            70:            (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 ||
        !            71:            (r = sshbuf_put(b, ckexinit, ckexinitlen)) != 0 ||
        !            72:            (r = sshbuf_put_u32(b, skexinitlen+1)) != 0 ||
        !            73:            (r = sshbuf_put_u8(b, SSH2_MSG_KEXINIT)) != 0 ||
        !            74:            (r = sshbuf_put(b, skexinit, skexinitlen)) != 0 ||
        !            75:            (r = sshbuf_put_string(b, serverhostkeyblob, sbloblen)) != 0 ||
        !            76:            (r = sshbuf_put_ec(b, client_dh_pub, ec_group)) != 0 ||
        !            77:            (r = sshbuf_put_ec(b, server_dh_pub, ec_group)) != 0 ||
        !            78:            (r = sshbuf_put_bignum2(b, shared_secret)) != 0) {
        !            79:                sshbuf_free(b);
        !            80:                return r;
        !            81:        }
1.1       djm        82: #ifdef DEBUG_KEX
1.6     ! markus     83:        sshbuf_dump(b, stderr);
1.1       djm        84: #endif
1.6     ! markus     85:        if (ssh_digest_buffer(hash_alg, b, hash, *hashlen) != 0) {
        !            86:                sshbuf_free(b);
        !            87:                return SSH_ERR_LIBCRYPTO_ERROR;
        !            88:        }
        !            89:        sshbuf_free(b);
        !            90:        *hashlen = ssh_digest_bytes(hash_alg);
1.1       djm        91: #ifdef DEBUG_KEX
1.6     ! markus     92:        dump_digest("hash", hash, *hashlen);
1.1       djm        93: #endif
1.6     ! markus     94:        return 0;
1.1       djm        95: }