blob: 99e9eea927d8e58bad96d0f536c13cdc7c7905da [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"
Darren Tucker129d0bb2005-12-19 17:40:40 +110026
27/* compatibility with old or broken OpenSSL versions */
28#include "openbsd-compat/openssl-compat.h"
29
30#ifdef USE_BUILTIN_RIJNDAEL
Damien Miller3a3261f2003-05-15 13:37:19 +100031
32#include <openssl/evp.h>
33#include "rijndael.h"
34#include "xmalloc.h"
35#include "log.h"
36
37#define RIJNDAEL_BLOCKSIZE 16
38struct ssh_rijndael_ctx
39{
40 rijndael_ctx r_ctx;
41 u_char r_iv[RIJNDAEL_BLOCKSIZE];
42};
43
44const EVP_CIPHER * evp_rijndael(void);
45void ssh_rijndael_iv(EVP_CIPHER_CTX *, int, u_char *, u_int);
46
47static int
48ssh_rijndael_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv,
49 int enc)
50{
51 struct ssh_rijndael_ctx *c;
52
53 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
54 c = xmalloc(sizeof(*c));
55 EVP_CIPHER_CTX_set_app_data(ctx, c);
56 }
57 if (key != NULL) {
58 if (enc == -1)
59 enc = ctx->encrypt;
60 rijndael_set_key(&c->r_ctx, (u_char *)key,
61 8*EVP_CIPHER_CTX_key_length(ctx), enc);
62 }
63 if (iv != NULL)
64 memcpy(c->r_iv, iv, RIJNDAEL_BLOCKSIZE);
65 return (1);
66}
67
68static int
69ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src,
70 u_int len)
71{
72 struct ssh_rijndael_ctx *c;
73 u_char buf[RIJNDAEL_BLOCKSIZE];
74 u_char *cprev, *cnow, *plain, *ivp;
75 int i, j, blocks = len / RIJNDAEL_BLOCKSIZE;
76
77 if (len == 0)
78 return (1);
79 if (len % RIJNDAEL_BLOCKSIZE)
80 fatal("ssh_rijndael_cbc: bad len %d", len);
81 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) {
82 error("ssh_rijndael_cbc: no context");
83 return (0);
84 }
85 if (ctx->encrypt) {
86 cnow = dest;
87 plain = (u_char *)src;
88 cprev = c->r_iv;
89 for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE,
90 cnow+=RIJNDAEL_BLOCKSIZE) {
91 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
92 buf[j] = plain[j] ^ cprev[j];
93 rijndael_encrypt(&c->r_ctx, buf, cnow);
94 cprev = cnow;
95 }
96 memcpy(c->r_iv, cprev, RIJNDAEL_BLOCKSIZE);
97 } else {
98 cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE);
99 plain = dest+len-RIJNDAEL_BLOCKSIZE;
100
101 memcpy(buf, cnow, RIJNDAEL_BLOCKSIZE);
102 for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
103 plain-=RIJNDAEL_BLOCKSIZE) {
104 rijndael_decrypt(&c->r_ctx, cnow, plain);
105 ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE;
106 for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
107 plain[j] ^= ivp[j];
108 }
109 memcpy(c->r_iv, buf, RIJNDAEL_BLOCKSIZE);
110 }
111 return (1);
112}
113
114static int
115ssh_rijndael_cleanup(EVP_CIPHER_CTX *ctx)
116{
117 struct ssh_rijndael_ctx *c;
118
119 if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) {
120 memset(c, 0, sizeof(*c));
121 xfree(c);
122 EVP_CIPHER_CTX_set_app_data(ctx, NULL);
123 }
124 return (1);
125}
126
127void
128ssh_rijndael_iv(EVP_CIPHER_CTX *evp, int doset, u_char * iv, u_int len)
129{
130 struct ssh_rijndael_ctx *c;
131
132 if ((c = EVP_CIPHER_CTX_get_app_data(evp)) == NULL)
133 fatal("ssh_rijndael_iv: no context");
134 if (doset)
135 memcpy(c->r_iv, iv, len);
136 else
137 memcpy(iv, c->r_iv, len);
138}
139
140const EVP_CIPHER *
141evp_rijndael(void)
142{
143 static EVP_CIPHER rijndal_cbc;
144
145 memset(&rijndal_cbc, 0, sizeof(EVP_CIPHER));
146 rijndal_cbc.nid = NID_undef;
147 rijndal_cbc.block_size = RIJNDAEL_BLOCKSIZE;
148 rijndal_cbc.iv_len = RIJNDAEL_BLOCKSIZE;
149 rijndal_cbc.key_len = 16;
150 rijndal_cbc.init = ssh_rijndael_init;
151 rijndal_cbc.cleanup = ssh_rijndael_cleanup;
152 rijndal_cbc.do_cipher = ssh_rijndael_cbc;
153#ifndef SSH_OLD_EVP
154 rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |
155 EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV;
156#endif
157 return (&rijndal_cbc);
158}
Darren Tucker129d0bb2005-12-19 17:40:40 +1100159#endif /* USE_BUILTIN_RIJNDAEL */