Annotation of src/usr.bin/ssh/cipher-bf1.c, Revision 1.1.6.1
1.1 markus 1: /*
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"
1.1.6.1 ! brad 26: RCSID("$OpenBSD: cipher-bf1.c,v 1.1 2003/05/15 03:08:29 markus Exp $");
1.1 markus 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:
36: const EVP_CIPHER * evp_ssh1_bf(void);
37:
38: static void
39: swap_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: static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, const u_char *, u_int) = NULL;
58:
59: static int
60: bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, u_int len)
61: {
62: int ret;
63:
64: swap_bytes(in, out, len);
65: ret = (*orig_bf)(ctx, out, out, len);
66: swap_bytes(out, out, len);
67: return (ret);
68: }
69:
70: const EVP_CIPHER *
71: evp_ssh1_bf(void)
72: {
73: static EVP_CIPHER ssh1_bf;
74:
75: memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER));
76: orig_bf = ssh1_bf.do_cipher;
77: ssh1_bf.nid = NID_undef;
78: ssh1_bf.do_cipher = bf_ssh1_cipher;
79: ssh1_bf.key_len = 32;
80: return (&ssh1_bf);
81: }