blob: 22d500d4290ab47cdd48bab52fde278d8dc8005c [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
Damien Miller3a3261f2003-05-15 13:37:19 +100025#include "includes.h"
Damien Millerdcc83122003-06-02 18:57:59 +100026#if OPENSSL_VERSION_NUMBER < 0x00907000L
Darren Tucker37afa9d2003-12-09 19:05:42 +110027RCSID("$OpenBSD: cipher-aes.c,v 1.2 2003/11/26 21:44:29 djm Exp $");
Damien Miller3a3261f2003-05-15 13:37:19 +100028
29#include <openssl/evp.h>
30#include "rijndael.h"
31#include "xmalloc.h"
32#include "log.h"
33
Damien Miller5c3a5582003-09-23 22:12:38 +100034#if OPENSSL_VERSION_NUMBER < 0x00906000L
35#define SSH_OLD_EVP
36#endif
37
Damien Miller3a3261f2003-05-15 13:37:19 +100038#define RIJNDAEL_BLOCKSIZE 16
39struct ssh_rijndael_ctx
40{
41 rijndael_ctx r_ctx;
42 u_char r_iv[RIJNDAEL_BLOCKSIZE];
43};
44
45const EVP_CIPHER * evp_rijndael(void);
46void ssh_rijndael_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
47
48static int
49ssh_rijndael_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
50 int enc)
51{
52 struct ssh_rijndael_ctx *c;
53
54 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
55 c = xmalloc(sizeof(*c));
56 EVP_CIPHER_CTX_set_app_data(ctx, c);
57 }
58 if (key != NULL) {
59 if (enc == -1)
60 enc = ctx->encrypt;
61 rijndael_set_key(&c->r_ctx, (u_char *)key,
62 8*EVP_CIPHER_CTX_key_length(ctx), enc);
63 }
64 if (iv != NULL)
65 memcpy(c->r_iv, iv, RIJNDAEL_BLOCKSIZE);
66 return (1);
67}
68
69static int
70ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src,
71 u_int len)
72{
73 struct ssh_rijndael_ctx *c;
74 u_char buf[RIJNDAEL_BLOCKSIZE];
75 u_char *cprev, *cnow, *plain, *ivp;
76 int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
77
78 if (len == 0)
79 return (1);
80 if (len % RIJNDAEL_BLOCKSIZE)
81 fatal("ssh_rijndael_cbc: bad len %d", len);
82 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
83 error("ssh_rijndael_cbc: no context");
84 return (0);
85 }
86 if (ctx->encrypt) {
87 cnow = dest;
88 plain = (u_char *)src;
89 cprev = c->r_iv;
90 for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE,
91 cnow+=RIJNDAEL_BLOCKSIZE) {
92 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
93 buf[j] = plain[j] ^ cprev[j];
94 rijndael_encrypt(&c->r_ctx, buf, cnow);
95 cprev = cnow;
96 }
97 memcpy(c->r_iv, cprev, RIJNDAEL_BLOCKSIZE);
98 } else {
99 cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE);
100 plain = dest+len-RIJNDAEL_BLOCKSIZE;
101
102 memcpy(buf, cnow, RIJNDAEL_BLOCKSIZE);
103 for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
104 plain-=RIJNDAEL_BLOCKSIZE) {
105 rijndael_decrypt(&c->r_ctx, cnow, plain);
106 ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE;
107 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
108 plain[j] ^= ivp[j];
109 }
110 memcpy(c->r_iv, buf, RIJNDAEL_BLOCKSIZE);
111 }
112 return (1);
113}
114
115static int
116ssh_rijndael_cleanup(EVP_CIPHER_CTX *ctx)
117{
118 struct ssh_rijndael_ctx *c;
119
120 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) {
121 memset(c, 0, sizeof(*c));
122 xfree(c);
123 EVP_CIPHER_CTX_set_app_data(ctx, NULL);
124 }
125 return (1);
126}
127
128void
129ssh_rijndael_iv(EVP_CIPHER_CTX *evp, int doset, u_char * iv, u_int len)
130{
131 struct ssh_rijndael_ctx *c;
132
133 if ((c = EVP_CIPHER_CTX_get_app_data(evp)) == NULL)
134 fatal("ssh_rijndael_iv: no context");
135 if (doset)
136 memcpy(c->r_iv, iv, len);
137 else
138 memcpy(iv, c->r_iv, len);
139}
140
141const EVP_CIPHER *
142evp_rijndael(void)
143{
144 static EVP_CIPHER rijndal_cbc;
145
146 memset(&rijndal_cbc, 0, sizeof(EVP_CIPHER));
147 rijndal_cbc.nid = NID_undef;
148 rijndal_cbc.block_size = RIJNDAEL_BLOCKSIZE;
149 rijndal_cbc.iv_len = RIJNDAEL_BLOCKSIZE;
150 rijndal_cbc.key_len = 16;
151 rijndal_cbc.init = ssh_rijndael_init;
152 rijndal_cbc.cleanup = ssh_rijndael_cleanup;
153 rijndal_cbc.do_cipher = ssh_rijndael_cbc;
154#ifndef SSH_OLD_EVP
155 rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |
156 EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV;
157#endif
158 return (&rijndal_cbc);
159}
Damien Millerdcc83122003-06-02 18:57:59 +1000160#endif /* OPENSSL_VERSION_NUMBER */