blob: 64578bae87dcb34e19508059584d3cadc672df09 [file] [log] [blame]
Damien Miller3a3261f2003-05-15 13:37:19 +10001/*
2 * Copyright (c) 2003 Markus Friedl. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
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.
12 *
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.
23 */
24
25#include "includes.h"
26RCSID("$OpenBSD: cipher-bf1.c,v 1.1 2003/05/15 03:08:29 markus Exp $");
27
28#include <openssl/evp.h>
29#include "xmalloc.h"
30#include "log.h"
31/*
32 * SSH1 uses a variation on Blowfish, all bytes must be swapped before
33 * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
34 */
35
36const EVP_CIPHER * evp_ssh1_bf(void);
37
38static void
39swap_bytes(const u_char *src, u_char *dst, int n)
40{
41 u_char c[4];
42
43 /* Process 4 bytes every lap. */
44 for (n = n / 4; n > 0; n--) {
45 c[3] = *src++;
46 c[2] = *src++;
47 c[1] = *src++;
48 c[0] = *src++;
49
50 *dst++ = c[0];
51 *dst++ = c[1];
52 *dst++ = c[2];
53 *dst++ = c[3];
54 }
55}
56
57#ifdef SSH_OLD_EVP
58static void bf_ssh1_init (EVP_CIPHER_CTX * ctx, const unsigned char *key,
59 const unsigned char *iv, int enc)
60{
61 if (iv != NULL)
62 memcpy (&(ctx->oiv[0]), iv, 8);
63 memcpy (&(ctx->iv[0]), &(ctx->oiv[0]), 8);
64 if (key != NULL)
65 BF_set_key (&(ctx->c.bf_ks), EVP_CIPHER_CTX_key_length (ctx),
66 key);
67}
68#endif
69
70static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, const u_char *, u_int) = NULL;
71
72static int
73bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, u_int len)
74{
75 int ret;
76
77 swap_bytes(in, out, len);
78 ret = (*orig_bf)(ctx, out, out, len);
79 swap_bytes(out, out, len);
80 return (ret);
81}
82
83const EVP_CIPHER *
84evp_ssh1_bf(void)
85{
86 static EVP_CIPHER ssh1_bf;
87
88 memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER));
89 orig_bf = ssh1_bf.do_cipher;
90 ssh1_bf.nid = NID_undef;
91#ifdef SSH_OLD_EVP
92 ssh1_bf.init = bf_ssh1_init;
93#endif
94 ssh1_bf.do_cipher = bf_ssh1_cipher;
95 ssh1_bf.key_len = 32;
96 return (&ssh1_bf);
97}