blob: bbfbe72108784046cde8452a699b46b04d2de9f6 [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#if OPENSSL_VERSION_NUMBER < 0x00907000L
26#include "includes.h"
27RCSID("$OpenBSD: cipher-aes.c,v 1.1 2003/05/15 03:08:29 markus Exp $");
28
29#include <openssl/evp.h>
30#include "rijndael.h"
31#include "xmalloc.h"
32#include "log.h"
33
34#define RIJNDAEL_BLOCKSIZE 16
35struct ssh_rijndael_ctx
36{
37 rijndael_ctx r_ctx;
38 u_char r_iv[RIJNDAEL_BLOCKSIZE];
39};
40
41const EVP_CIPHER * evp_rijndael(void);
42void ssh_rijndael_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
43
44static int
45ssh_rijndael_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
46 int enc)
47{
48 struct ssh_rijndael_ctx *c;
49
50 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
51 c = xmalloc(sizeof(*c));
52 EVP_CIPHER_CTX_set_app_data(ctx, c);
53 }
54 if (key != NULL) {
55 if (enc == -1)
56 enc = ctx->encrypt;
57 rijndael_set_key(&c->r_ctx, (u_char *)key,
58 8*EVP_CIPHER_CTX_key_length(ctx), enc);
59 }
60 if (iv != NULL)
61 memcpy(c->r_iv, iv, RIJNDAEL_BLOCKSIZE);
62 return (1);
63}
64
65static int
66ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src,
67 u_int len)
68{
69 struct ssh_rijndael_ctx *c;
70 u_char buf[RIJNDAEL_BLOCKSIZE];
71 u_char *cprev, *cnow, *plain, *ivp;
72 int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
73
74 if (len == 0)
75 return (1);
76 if (len % RIJNDAEL_BLOCKSIZE)
77 fatal("ssh_rijndael_cbc: bad len %d", len);
78 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
79 error("ssh_rijndael_cbc: no context");
80 return (0);
81 }
82 if (ctx->encrypt) {
83 cnow = dest;
84 plain = (u_char *)src;
85 cprev = c->r_iv;
86 for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE,
87 cnow+=RIJNDAEL_BLOCKSIZE) {
88 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
89 buf[j] = plain[j] ^ cprev[j];
90 rijndael_encrypt(&c->r_ctx, buf, cnow);
91 cprev = cnow;
92 }
93 memcpy(c->r_iv, cprev, RIJNDAEL_BLOCKSIZE);
94 } else {
95 cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE);
96 plain = dest+len-RIJNDAEL_BLOCKSIZE;
97
98 memcpy(buf, cnow, RIJNDAEL_BLOCKSIZE);
99 for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
100 plain-=RIJNDAEL_BLOCKSIZE) {
101 rijndael_decrypt(&c->r_ctx, cnow, plain);
102 ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE;
103 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
104 plain[j] ^= ivp[j];
105 }
106 memcpy(c->r_iv, buf, RIJNDAEL_BLOCKSIZE);
107 }
108 return (1);
109}
110
111static int
112ssh_rijndael_cleanup(EVP_CIPHER_CTX *ctx)
113{
114 struct ssh_rijndael_ctx *c;
115
116 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) {
117 memset(c, 0, sizeof(*c));
118 xfree(c);
119 EVP_CIPHER_CTX_set_app_data(ctx, NULL);
120 }
121 return (1);
122}
123
124void
125ssh_rijndael_iv(EVP_CIPHER_CTX *evp, int doset, u_char * iv, u_int len)
126{
127 struct ssh_rijndael_ctx *c;
128
129 if ((c = EVP_CIPHER_CTX_get_app_data(evp)) == NULL)
130 fatal("ssh_rijndael_iv: no context");
131 if (doset)
132 memcpy(c->r_iv, iv, len);
133 else
134 memcpy(iv, c->r_iv, len);
135}
136
137const EVP_CIPHER *
138evp_rijndael(void)
139{
140 static EVP_CIPHER rijndal_cbc;
141
142 memset(&rijndal_cbc, 0, sizeof(EVP_CIPHER));
143 rijndal_cbc.nid = NID_undef;
144 rijndal_cbc.block_size = RIJNDAEL_BLOCKSIZE;
145 rijndal_cbc.iv_len = RIJNDAEL_BLOCKSIZE;
146 rijndal_cbc.key_len = 16;
147 rijndal_cbc.init = ssh_rijndael_init;
148 rijndal_cbc.cleanup = ssh_rijndael_cleanup;
149 rijndal_cbc.do_cipher = ssh_rijndael_cbc;
150#ifndef SSH_OLD_EVP
151 rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |
152 EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV;
153#endif
154 return (&rijndal_cbc);
155}
156#endif