blob: 309509dd780694822b28b81809a88797a6f8eb06 [file] [log] [blame]
Damien Miller9a3d0dc2010-10-07 22:06:42 +11001/* $OpenBSD: cipher-bf1.c,v 1.6 2010/10/01 23:05:32 djm Exp $ */
Damien Miller3a3261f2003-05-15 13:37:19 +10002/*
3 * Copyright (c) 2003 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"
Damien Miller3a3261f2003-05-15 13:37:19 +100027
Damien Millerd7834352006-08-05 12:39:39 +100028#include <sys/types.h>
29
Damien Miller3a3261f2003-05-15 13:37:19 +100030#include <openssl/evp.h>
Damien Millere3476ed2006-07-24 14:13:33 +100031
Damien Millerded319c2006-09-01 15:38:36 +100032#include <stdarg.h>
Damien Millere3476ed2006-07-24 14:13:33 +100033#include <string.h>
34
Damien Miller3a3261f2003-05-15 13:37:19 +100035#include "xmalloc.h"
36#include "log.h"
Damien Miller5c3a5582003-09-23 22:12:38 +100037
Darren Tuckerda05f482007-03-13 18:50:04 +110038#include "openbsd-compat/openssl-compat.h"
Damien Miller5c3a5582003-09-23 22:12:38 +100039
Damien Miller3a3261f2003-05-15 13:37:19 +100040/*
41 * SSH1 uses a variation on Blowfish, all bytes must be swapped before
42 * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
43 */
44
45const EVP_CIPHER * evp_ssh1_bf(void);
46
47static void
48swap_bytes(const u_char *src, u_char *dst, int n)
49{
50 u_char c[4];
51
52 /* Process 4 bytes every lap. */
53 for (n = n / 4; n > 0; n--) {
54 c[3] = *src++;
55 c[2] = *src++;
56 c[1] = *src++;
57 c[0] = *src++;
58
59 *dst++ = c[0];
60 *dst++ = c[1];
61 *dst++ = c[2];
62 *dst++ = c[3];
63 }
64}
65
66#ifdef SSH_OLD_EVP
67static void bf_ssh1_init (EVP_CIPHER_CTX * ctx, const unsigned char *key,
68 const unsigned char *iv, int enc)
69{
70 if (iv != NULL)
71 memcpy (&(ctx->oiv[0]), iv, 8);
72 memcpy (&(ctx->iv[0]), &(ctx->oiv[0]), 8);
73 if (key != NULL)
74 BF_set_key (&(ctx->c.bf_ks), EVP_CIPHER_CTX_key_length (ctx),
75 key);
76}
77#endif
78
Damien Miller9a3d0dc2010-10-07 22:06:42 +110079static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *,
80 const u_char *, LIBCRYPTO_EVP_INL_TYPE) = NULL;
Damien Miller3a3261f2003-05-15 13:37:19 +100081
82static int
Damien Miller9a3d0dc2010-10-07 22:06:42 +110083bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in,
84 LIBCRYPTO_EVP_INL_TYPE len)
Damien Miller3a3261f2003-05-15 13:37:19 +100085{
86 int ret;
87
88 swap_bytes(in, out, len);
89 ret = (*orig_bf)(ctx, out, out, len);
90 swap_bytes(out, out, len);
91 return (ret);
92}
93
94const EVP_CIPHER *
95evp_ssh1_bf(void)
96{
97 static EVP_CIPHER ssh1_bf;
98
99 memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER));
100 orig_bf = ssh1_bf.do_cipher;
101 ssh1_bf.nid = NID_undef;
102#ifdef SSH_OLD_EVP
103 ssh1_bf.init = bf_ssh1_init;
104#endif
105 ssh1_bf.do_cipher = bf_ssh1_cipher;
106 ssh1_bf.key_len = 32;
107 return (&ssh1_bf);
108}