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3c0ef626 | 1 | /* |
2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
5 | * | |
6 | * As far as I am concerned, the code I have written for this software | |
7 | * can be used freely for any purpose. Any derived versions of this | |
8 | * software must be clearly marked as such, and if the derived work is | |
9 | * incompatible with the protocol description in the RFC file, it must be | |
10 | * called by a name other than "ssh" or "Secure Shell". | |
11 | * | |
12 | * | |
13 | * Copyright (c) 1999 Niels Provos. All rights reserved. | |
14 | * Copyright (c) 1999, 2000 Markus Friedl. All rights reserved. | |
15 | * | |
16 | * Redistribution and use in source and binary forms, with or without | |
17 | * modification, are permitted provided that the following conditions | |
18 | * are met: | |
19 | * 1. Redistributions of source code must retain the above copyright | |
20 | * notice, this list of conditions and the following disclaimer. | |
21 | * 2. Redistributions in binary form must reproduce the above copyright | |
22 | * notice, this list of conditions and the following disclaimer in the | |
23 | * documentation and/or other materials provided with the distribution. | |
24 | * | |
25 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
26 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
27 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
28 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
29 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
30 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
31 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
32 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
33 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
34 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
35 | */ | |
36 | ||
37 | #include "includes.h" | |
905081a4 | 38 | RCSID("$OpenBSD: cipher.c,v 1.54 2002/03/19 10:49:35 markus Exp $"); |
3c0ef626 | 39 | |
40 | #include "xmalloc.h" | |
41 | #include "log.h" | |
42 | #include "cipher.h" | |
43 | ||
44 | #include <openssl/md5.h> | |
905081a4 | 45 | #include "rijndael.h" |
46 | ||
47 | static EVP_CIPHER *evp_ssh1_3des(void); | |
48 | static EVP_CIPHER *evp_ssh1_bf(void); | |
49 | static EVP_CIPHER *evp_rijndael(void); | |
50 | ||
51 | struct Cipher { | |
52 | char *name; | |
53 | int number; /* for ssh1 only */ | |
54 | u_int block_size; | |
55 | u_int key_len; | |
56 | EVP_CIPHER *(*evptype)(void); | |
57 | } ciphers[] = { | |
58 | { "none", SSH_CIPHER_NONE, 8, 0, EVP_enc_null }, | |
59 | { "des", SSH_CIPHER_DES, 8, 8, EVP_des_cbc }, | |
60 | { "3des", SSH_CIPHER_3DES, 8, 16, evp_ssh1_3des }, | |
61 | { "blowfish", SSH_CIPHER_BLOWFISH, 8, 32, evp_ssh1_bf }, | |
62 | ||
63 | { "3des-cbc", SSH_CIPHER_SSH2, 8, 24, EVP_des_ede3_cbc }, | |
64 | { "blowfish-cbc", SSH_CIPHER_SSH2, 8, 16, EVP_bf_cbc }, | |
65 | { "cast128-cbc", SSH_CIPHER_SSH2, 8, 16, EVP_cast5_cbc }, | |
66 | { "arcfour", SSH_CIPHER_SSH2, 8, 16, EVP_rc4 }, | |
67 | { "aes128-cbc", SSH_CIPHER_SSH2, 16, 16, evp_rijndael }, | |
68 | { "aes192-cbc", SSH_CIPHER_SSH2, 16, 24, evp_rijndael }, | |
69 | { "aes256-cbc", SSH_CIPHER_SSH2, 16, 32, evp_rijndael }, | |
70 | ||
71 | { NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL } | |
72 | }; | |
3c0ef626 | 73 | |
905081a4 | 74 | /*--*/ |
3c0ef626 | 75 | |
905081a4 | 76 | u_int |
77 | cipher_blocksize(Cipher *c) | |
3c0ef626 | 78 | { |
905081a4 | 79 | return (c->block_size); |
3c0ef626 | 80 | } |
905081a4 | 81 | u_int |
82 | cipher_keylen(Cipher *c) | |
3c0ef626 | 83 | { |
905081a4 | 84 | return (c->key_len); |
3c0ef626 | 85 | } |
905081a4 | 86 | u_int |
87 | cipher_get_number(Cipher *c) | |
3c0ef626 | 88 | { |
905081a4 | 89 | return (c->number); |
3c0ef626 | 90 | } |
91 | ||
3c0ef626 | 92 | u_int |
93 | cipher_mask_ssh1(int client) | |
94 | { | |
95 | u_int mask = 0; | |
905081a4 | 96 | mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */ |
3c0ef626 | 97 | mask |= 1 << SSH_CIPHER_BLOWFISH; |
98 | if (client) { | |
99 | mask |= 1 << SSH_CIPHER_DES; | |
100 | } | |
101 | return mask; | |
102 | } | |
103 | ||
104 | Cipher * | |
105 | cipher_by_name(const char *name) | |
106 | { | |
107 | Cipher *c; | |
108 | for (c = ciphers; c->name != NULL; c++) | |
109 | if (strcasecmp(c->name, name) == 0) | |
110 | return c; | |
111 | return NULL; | |
112 | } | |
113 | ||
114 | Cipher * | |
115 | cipher_by_number(int id) | |
116 | { | |
117 | Cipher *c; | |
118 | for (c = ciphers; c->name != NULL; c++) | |
119 | if (c->number == id) | |
120 | return c; | |
121 | return NULL; | |
122 | } | |
123 | ||
124 | #define CIPHER_SEP "," | |
125 | int | |
126 | ciphers_valid(const char *names) | |
127 | { | |
128 | Cipher *c; | |
129 | char *ciphers, *cp; | |
130 | char *p; | |
131 | ||
132 | if (names == NULL || strcmp(names, "") == 0) | |
133 | return 0; | |
134 | ciphers = cp = xstrdup(names); | |
135 | for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0'; | |
905081a4 | 136 | (p = strsep(&cp, CIPHER_SEP))) { |
3c0ef626 | 137 | c = cipher_by_name(p); |
138 | if (c == NULL || c->number != SSH_CIPHER_SSH2) { | |
139 | debug("bad cipher %s [%s]", p, names); | |
140 | xfree(ciphers); | |
141 | return 0; | |
142 | } else { | |
143 | debug3("cipher ok: %s [%s]", p, names); | |
144 | } | |
145 | } | |
146 | debug3("ciphers ok: [%s]", names); | |
147 | xfree(ciphers); | |
148 | return 1; | |
149 | } | |
150 | ||
151 | /* | |
152 | * Parses the name of the cipher. Returns the number of the corresponding | |
153 | * cipher, or -1 on error. | |
154 | */ | |
155 | ||
156 | int | |
157 | cipher_number(const char *name) | |
158 | { | |
159 | Cipher *c; | |
160 | if (name == NULL) | |
161 | return -1; | |
162 | c = cipher_by_name(name); | |
163 | return (c==NULL) ? -1 : c->number; | |
164 | } | |
165 | ||
166 | char * | |
167 | cipher_name(int id) | |
168 | { | |
169 | Cipher *c = cipher_by_number(id); | |
170 | return (c==NULL) ? "<unknown>" : c->name; | |
171 | } | |
172 | ||
173 | void | |
174 | cipher_init(CipherContext *cc, Cipher *cipher, | |
905081a4 | 175 | const u_char *key, u_int keylen, const u_char *iv, u_int ivlen, |
176 | int encrypt) | |
3c0ef626 | 177 | { |
905081a4 | 178 | static int dowarn = 1; |
179 | const EVP_CIPHER *type; | |
180 | int klen; | |
181 | ||
182 | if (cipher->number == SSH_CIPHER_DES) { | |
183 | if (dowarn) { | |
184 | error("Warning: use of DES is strongly discouraged " | |
185 | "due to cryptographic weaknesses"); | |
186 | dowarn = 0; | |
187 | } | |
188 | if (keylen > 8) | |
189 | keylen = 8; | |
190 | } | |
191 | cc->plaintext = (cipher->number == SSH_CIPHER_NONE); | |
192 | ||
3c0ef626 | 193 | if (keylen < cipher->key_len) |
194 | fatal("cipher_init: key length %d is insufficient for %s.", | |
195 | keylen, cipher->name); | |
196 | if (iv != NULL && ivlen < cipher->block_size) | |
197 | fatal("cipher_init: iv length %d is insufficient for %s.", | |
198 | ivlen, cipher->name); | |
199 | cc->cipher = cipher; | |
905081a4 | 200 | |
201 | type = (*cipher->evptype)(); | |
202 | ||
203 | EVP_CIPHER_CTX_init(&cc->evp); | |
204 | if (EVP_CipherInit(&cc->evp, type, NULL, (u_char *)iv, | |
205 | (encrypt == CIPHER_ENCRYPT)) == 0) | |
206 | fatal("cipher_init: EVP_CipherInit failed for %s", | |
207 | cipher->name); | |
208 | klen = EVP_CIPHER_CTX_key_length(&cc->evp); | |
209 | if (klen > 0 && keylen != klen) { | |
210 | debug("cipher_init: set keylen (%d -> %d)", klen, keylen); | |
211 | if (EVP_CIPHER_CTX_set_key_length(&cc->evp, keylen) == 0) | |
212 | fatal("cipher_init: set keylen failed (%d -> %d)", | |
213 | klen, keylen); | |
214 | } | |
215 | if (EVP_CipherInit(&cc->evp, NULL, (u_char *)key, NULL, -1) == 0) | |
216 | fatal("cipher_init: EVP_CipherInit: set key failed for %s", | |
217 | cipher->name); | |
3c0ef626 | 218 | } |
219 | ||
220 | void | |
905081a4 | 221 | cipher_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len) |
3c0ef626 | 222 | { |
223 | if (len % cc->cipher->block_size) | |
224 | fatal("cipher_encrypt: bad plaintext length %d", len); | |
905081a4 | 225 | if (EVP_Cipher(&cc->evp, dest, (u_char *)src, len) == 0) |
226 | fatal("evp_crypt: EVP_Cipher failed"); | |
3c0ef626 | 227 | } |
228 | ||
229 | void | |
905081a4 | 230 | cipher_cleanup(CipherContext *cc) |
3c0ef626 | 231 | { |
905081a4 | 232 | if (EVP_CIPHER_CTX_cleanup(&cc->evp) == 0) |
233 | error("cipher_cleanup: EVP_CIPHER_CTX_cleanup failed"); | |
3c0ef626 | 234 | } |
235 | ||
236 | /* | |
237 | * Selects the cipher, and keys if by computing the MD5 checksum of the | |
238 | * passphrase and using the resulting 16 bytes as the key. | |
239 | */ | |
240 | ||
241 | void | |
242 | cipher_set_key_string(CipherContext *cc, Cipher *cipher, | |
905081a4 | 243 | const char *passphrase, int encrypt) |
3c0ef626 | 244 | { |
245 | MD5_CTX md; | |
246 | u_char digest[16]; | |
247 | ||
248 | MD5_Init(&md); | |
249 | MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase)); | |
250 | MD5_Final(digest, &md); | |
251 | ||
905081a4 | 252 | cipher_init(cc, cipher, digest, 16, NULL, 0, encrypt); |
3c0ef626 | 253 | |
254 | memset(digest, 0, sizeof(digest)); | |
255 | memset(&md, 0, sizeof(md)); | |
256 | } | |
905081a4 | 257 | |
258 | /* Implementations for other non-EVP ciphers */ | |
259 | ||
260 | /* | |
261 | * This is used by SSH1: | |
262 | * | |
263 | * What kind of triple DES are these 2 routines? | |
264 | * | |
265 | * Why is there a redundant initialization vector? | |
266 | * | |
267 | * If only iv3 was used, then, this would till effect have been | |
268 | * outer-cbc. However, there is also a private iv1 == iv2 which | |
269 | * perhaps makes differential analysis easier. On the other hand, the | |
270 | * private iv1 probably makes the CRC-32 attack ineffective. This is a | |
271 | * result of that there is no longer any known iv1 to use when | |
272 | * choosing the X block. | |
273 | */ | |
274 | struct ssh1_3des_ctx | |
275 | { | |
276 | EVP_CIPHER_CTX k1, k2, k3; | |
277 | }; | |
278 | static int | |
279 | ssh1_3des_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv, | |
280 | int enc) | |
281 | { | |
282 | struct ssh1_3des_ctx *c; | |
283 | u_char *k1, *k2, *k3; | |
284 | ||
285 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) { | |
286 | c = xmalloc(sizeof(*c)); | |
287 | EVP_CIPHER_CTX_set_app_data(ctx, c); | |
288 | } | |
289 | if (key == NULL) | |
290 | return (1); | |
291 | if (enc == -1) | |
292 | enc = ctx->encrypt; | |
293 | k1 = k2 = k3 = (u_char *) key; | |
294 | k2 += 8; | |
295 | if (EVP_CIPHER_CTX_key_length(ctx) >= 16+8) { | |
296 | if (enc) | |
297 | k3 += 16; | |
298 | else | |
299 | k1 += 16; | |
300 | } | |
301 | EVP_CIPHER_CTX_init(&c->k1); | |
302 | EVP_CIPHER_CTX_init(&c->k2); | |
303 | EVP_CIPHER_CTX_init(&c->k3); | |
304 | if (EVP_CipherInit(&c->k1, EVP_des_cbc(), k1, NULL, enc) == 0 || | |
305 | EVP_CipherInit(&c->k2, EVP_des_cbc(), k2, NULL, !enc) == 0 || | |
306 | EVP_CipherInit(&c->k3, EVP_des_cbc(), k3, NULL, enc) == 0) { | |
307 | memset(c, 0, sizeof(*c)); | |
308 | xfree(c); | |
309 | EVP_CIPHER_CTX_set_app_data(ctx, NULL); | |
310 | return (0); | |
311 | } | |
312 | return (1); | |
313 | } | |
314 | static int | |
315 | ssh1_3des_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src, u_int len) | |
316 | { | |
317 | struct ssh1_3des_ctx *c; | |
318 | ||
319 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) { | |
320 | error("ssh1_3des_cbc: no context"); | |
321 | return (0); | |
322 | } | |
323 | if (EVP_Cipher(&c->k1, dest, (u_char *)src, len) == 0 || | |
324 | EVP_Cipher(&c->k2, dest, dest, len) == 0 || | |
325 | EVP_Cipher(&c->k3, dest, dest, len) == 0) | |
326 | return (0); | |
327 | return (1); | |
328 | } | |
329 | static int | |
330 | ssh1_3des_cleanup(EVP_CIPHER_CTX *ctx) | |
331 | { | |
332 | struct ssh1_3des_ctx *c; | |
333 | ||
334 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) { | |
335 | memset(c, 0, sizeof(*c)); | |
336 | xfree(c); | |
337 | EVP_CIPHER_CTX_set_app_data(ctx, NULL); | |
338 | } | |
339 | return (1); | |
340 | } | |
341 | static EVP_CIPHER * | |
342 | evp_ssh1_3des(void) | |
343 | { | |
344 | static EVP_CIPHER ssh1_3des; | |
345 | ||
346 | memset(&ssh1_3des, 0, sizeof(EVP_CIPHER)); | |
347 | ssh1_3des.nid = NID_undef; | |
348 | ssh1_3des.block_size = 8; | |
349 | ssh1_3des.iv_len = 0; | |
350 | ssh1_3des.key_len = 16; | |
351 | ssh1_3des.init = ssh1_3des_init; | |
352 | ssh1_3des.cleanup = ssh1_3des_cleanup; | |
353 | ssh1_3des.do_cipher = ssh1_3des_cbc; | |
354 | ssh1_3des.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH; | |
355 | return (&ssh1_3des); | |
356 | } | |
357 | ||
358 | /* | |
359 | * SSH1 uses a variation on Blowfish, all bytes must be swapped before | |
360 | * and after encryption/decryption. Thus the swap_bytes stuff (yuk). | |
361 | */ | |
362 | static void | |
363 | swap_bytes(const u_char *src, u_char *dst, int n) | |
364 | { | |
365 | u_char c[4]; | |
366 | ||
367 | /* Process 4 bytes every lap. */ | |
368 | for (n = n / 4; n > 0; n--) { | |
369 | c[3] = *src++; | |
370 | c[2] = *src++; | |
371 | c[1] = *src++; | |
372 | c[0] = *src++; | |
373 | ||
374 | *dst++ = c[0]; | |
375 | *dst++ = c[1]; | |
376 | *dst++ = c[2]; | |
377 | *dst++ = c[3]; | |
378 | } | |
379 | } | |
380 | static int (*orig_bf)(EVP_CIPHER_CTX *, u_char *, const u_char *, u_int) = NULL; | |
381 | static int | |
382 | bf_ssh1_cipher(EVP_CIPHER_CTX *ctx, u_char *out, const u_char *in, u_int len) | |
383 | { | |
384 | int ret; | |
385 | ||
386 | swap_bytes(in, out, len); | |
387 | ret = (*orig_bf)(ctx, out, out, len); | |
388 | swap_bytes(out, out, len); | |
389 | return (ret); | |
390 | } | |
391 | static EVP_CIPHER * | |
392 | evp_ssh1_bf(void) | |
393 | { | |
394 | static EVP_CIPHER ssh1_bf; | |
395 | ||
396 | memcpy(&ssh1_bf, EVP_bf_cbc(), sizeof(EVP_CIPHER)); | |
397 | orig_bf = ssh1_bf.do_cipher; | |
398 | ssh1_bf.nid = NID_undef; | |
399 | ssh1_bf.do_cipher = bf_ssh1_cipher; | |
400 | ssh1_bf.key_len = 32; | |
401 | return (&ssh1_bf); | |
402 | } | |
403 | ||
404 | /* RIJNDAEL */ | |
405 | #define RIJNDAEL_BLOCKSIZE 16 | |
406 | struct ssh_rijndael_ctx | |
407 | { | |
408 | rijndael_ctx r_ctx; | |
409 | u_char r_iv[RIJNDAEL_BLOCKSIZE]; | |
410 | }; | |
411 | ||
412 | static int | |
413 | ssh_rijndael_init(EVP_CIPHER_CTX *ctx, const u_char *key, const u_char *iv, | |
414 | int enc) | |
415 | { | |
416 | struct ssh_rijndael_ctx *c; | |
417 | ||
418 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) { | |
419 | c = xmalloc(sizeof(*c)); | |
420 | EVP_CIPHER_CTX_set_app_data(ctx, c); | |
421 | } | |
422 | if (key != NULL) { | |
423 | if (enc == -1) | |
424 | enc = ctx->encrypt; | |
425 | rijndael_set_key(&c->r_ctx, (u_char *)key, | |
426 | 8*EVP_CIPHER_CTX_key_length(ctx), enc); | |
427 | } | |
428 | if (iv != NULL) | |
429 | memcpy(c->r_iv, iv, RIJNDAEL_BLOCKSIZE); | |
430 | return (1); | |
431 | } | |
432 | static int | |
433 | ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src, | |
434 | u_int len) | |
435 | { | |
436 | struct ssh_rijndael_ctx *c; | |
437 | u_char buf[RIJNDAEL_BLOCKSIZE]; | |
438 | u_char *cprev, *cnow, *plain, *ivp; | |
439 | int i, j, blocks = len / RIJNDAEL_BLOCKSIZE; | |
440 | ||
441 | if (len == 0) | |
442 | return (1); | |
443 | if (len % RIJNDAEL_BLOCKSIZE) | |
444 | fatal("ssh_rijndael_cbc: bad len %d", len); | |
445 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL) { | |
446 | error("ssh_rijndael_cbc: no context"); | |
447 | return (0); | |
448 | } | |
449 | if (ctx->encrypt) { | |
450 | cnow = dest; | |
451 | plain = (u_char *)src; | |
452 | cprev = c->r_iv; | |
453 | for (i = 0; i < blocks; i++, plain+=RIJNDAEL_BLOCKSIZE, | |
454 | cnow+=RIJNDAEL_BLOCKSIZE) { | |
455 | for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++) | |
456 | buf[j] = plain[j] ^ cprev[j]; | |
457 | rijndael_encrypt(&c->r_ctx, buf, cnow); | |
458 | cprev = cnow; | |
459 | } | |
460 | memcpy(c->r_iv, cprev, RIJNDAEL_BLOCKSIZE); | |
461 | } else { | |
462 | cnow = (u_char *) (src+len-RIJNDAEL_BLOCKSIZE); | |
463 | plain = dest+len-RIJNDAEL_BLOCKSIZE; | |
464 | ||
465 | memcpy(buf, cnow, RIJNDAEL_BLOCKSIZE); | |
466 | for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE, | |
467 | plain-=RIJNDAEL_BLOCKSIZE) { | |
468 | rijndael_decrypt(&c->r_ctx, cnow, plain); | |
469 | ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE; | |
470 | for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++) | |
471 | plain[j] ^= ivp[j]; | |
472 | } | |
473 | memcpy(c->r_iv, buf, RIJNDAEL_BLOCKSIZE); | |
474 | } | |
475 | return (1); | |
476 | } | |
477 | static int | |
478 | ssh_rijndael_cleanup(EVP_CIPHER_CTX *ctx) | |
479 | { | |
480 | struct ssh_rijndael_ctx *c; | |
481 | ||
482 | if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) { | |
483 | memset(c, 0, sizeof(*c)); | |
484 | xfree(c); | |
485 | EVP_CIPHER_CTX_set_app_data(ctx, NULL); | |
486 | } | |
487 | return (1); | |
488 | } | |
489 | static EVP_CIPHER * | |
490 | evp_rijndael(void) | |
491 | { | |
492 | static EVP_CIPHER rijndal_cbc; | |
493 | ||
494 | memset(&rijndal_cbc, 0, sizeof(EVP_CIPHER)); | |
495 | rijndal_cbc.nid = NID_undef; | |
496 | rijndal_cbc.block_size = RIJNDAEL_BLOCKSIZE; | |
497 | rijndal_cbc.iv_len = RIJNDAEL_BLOCKSIZE; | |
498 | rijndal_cbc.key_len = 16; | |
499 | rijndal_cbc.init = ssh_rijndael_init; | |
500 | rijndal_cbc.cleanup = ssh_rijndael_cleanup; | |
501 | rijndal_cbc.do_cipher = ssh_rijndael_cbc; | |
502 | rijndal_cbc.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | | |
503 | EVP_CIPH_ALWAYS_CALL_INIT; | |
504 | return (&rijndal_cbc); | |
505 | } | |
506 | ||
507 | /* | |
508 | * Exports an IV from the CipherContext required to export the key | |
509 | * state back from the unprivileged child to the privileged parent | |
510 | * process. | |
511 | */ | |
512 | ||
513 | int | |
514 | cipher_get_keyiv_len(CipherContext *cc) | |
515 | { | |
516 | Cipher *c = cc->cipher; | |
517 | int ivlen; | |
518 | ||
519 | if (c->number == SSH_CIPHER_3DES) | |
520 | ivlen = 24; | |
521 | else | |
522 | ivlen = EVP_CIPHER_CTX_iv_length(&cc->evp); | |
523 | return (ivlen); | |
524 | } | |
525 | ||
526 | void | |
527 | cipher_get_keyiv(CipherContext *cc, u_char *iv, u_int len) | |
528 | { | |
529 | Cipher *c = cc->cipher; | |
530 | u_char *civ = NULL; | |
531 | int evplen; | |
532 | ||
533 | switch (c->number) { | |
534 | case SSH_CIPHER_SSH2: | |
535 | case SSH_CIPHER_DES: | |
536 | case SSH_CIPHER_BLOWFISH: | |
537 | evplen = EVP_CIPHER_CTX_iv_length(&cc->evp); | |
538 | if (evplen == 0) | |
539 | return; | |
540 | if (evplen != len) | |
b511e0d0 | 541 | fatal("cipher_get_keyiv: wrong iv length %d != %d", |
905081a4 | 542 | evplen, len); |
543 | ||
544 | if (strncmp(c->name, "aes", 3) == 0) { | |
545 | struct ssh_rijndael_ctx *aesc; | |
546 | ||
547 | aesc = EVP_CIPHER_CTX_get_app_data(&cc->evp); | |
548 | if (aesc == NULL) | |
b511e0d0 | 549 | fatal("cipher_get_keyiv: no rijndael context"); |
905081a4 | 550 | civ = aesc->r_iv; |
551 | } else { | |
552 | civ = cc->evp.iv; | |
553 | } | |
554 | break; | |
555 | case SSH_CIPHER_3DES: { | |
556 | struct ssh1_3des_ctx *desc; | |
557 | if (len != 24) | |
b511e0d0 | 558 | fatal("cipher_get_keyiv: bad 3des iv length: %d", len); |
905081a4 | 559 | desc = EVP_CIPHER_CTX_get_app_data(&cc->evp); |
560 | if (desc == NULL) | |
b511e0d0 | 561 | fatal("cipher_get_keyiv: no 3des context"); |
562 | debug3("cipher_get_keyiv: Copying 3DES IV"); | |
905081a4 | 563 | memcpy(iv, desc->k1.iv, 8); |
564 | memcpy(iv + 8, desc->k2.iv, 8); | |
565 | memcpy(iv + 16, desc->k3.iv, 8); | |
566 | return; | |
567 | } | |
568 | default: | |
b511e0d0 | 569 | fatal("cipher_get_keyiv: bad cipher %d", c->number); |
905081a4 | 570 | } |
571 | memcpy(iv, civ, len); | |
572 | } | |
573 | ||
574 | void | |
575 | cipher_set_keyiv(CipherContext *cc, u_char *iv) | |
576 | { | |
577 | Cipher *c = cc->cipher; | |
578 | u_char *div = NULL; | |
579 | int evplen = 0; | |
580 | ||
581 | switch (c->number) { | |
582 | case SSH_CIPHER_SSH2: | |
583 | case SSH_CIPHER_DES: | |
584 | case SSH_CIPHER_BLOWFISH: | |
585 | evplen = EVP_CIPHER_CTX_iv_length(&cc->evp); | |
586 | if (evplen == 0) | |
587 | return; | |
588 | ||
589 | if (strncmp(c->name, "aes", 3) == 0) { | |
590 | struct ssh_rijndael_ctx *aesc; | |
591 | ||
592 | aesc = EVP_CIPHER_CTX_get_app_data(&cc->evp); | |
593 | if (aesc == NULL) | |
b511e0d0 | 594 | fatal("cipher_set_keyiv: no rijndael context"); |
905081a4 | 595 | div = aesc->r_iv; |
596 | }else { | |
597 | div = cc->evp.iv; | |
598 | } | |
599 | break; | |
600 | case SSH_CIPHER_3DES: { | |
601 | struct ssh1_3des_ctx *desc; | |
602 | desc = EVP_CIPHER_CTX_get_app_data(&cc->evp); | |
603 | if (desc == NULL) | |
b511e0d0 | 604 | fatal("cipher_set_keyiv: no 3des context"); |
605 | debug3("cipher_set_keyiv: Installed 3DES IV"); | |
905081a4 | 606 | memcpy(desc->k1.iv, iv, 8); |
607 | memcpy(desc->k2.iv, iv + 8, 8); | |
608 | memcpy(desc->k3.iv, iv + 16, 8); | |
609 | return; | |
610 | } | |
611 | default: | |
b511e0d0 | 612 | fatal("cipher_set_keyiv: bad cipher %d", c->number); |
905081a4 | 613 | } |
614 | memcpy(div, iv, evplen); | |
615 | } | |
616 | ||
617 | #if OPENSSL_VERSION_NUMBER < 0x00907000L | |
618 | #define EVP_X_STATE(evp) &(evp).c | |
619 | #define EVP_X_STATE_LEN(evp) sizeof((evp).c) | |
620 | #else | |
621 | #define EVP_X_STATE(evp) (evp).cipher_data | |
622 | #define EVP_X_STATE_LEN(evp) (evp).cipher->ctx_size | |
623 | #endif | |
624 | ||
625 | int | |
626 | cipher_get_keycontext(CipherContext *cc, u_char *dat) | |
627 | { | |
628 | Cipher *c = cc->cipher; | |
629 | int plen; | |
630 | ||
631 | if (c->number == SSH_CIPHER_3DES) { | |
632 | struct ssh1_3des_ctx *desc; | |
633 | desc = EVP_CIPHER_CTX_get_app_data(&cc->evp); | |
634 | if (desc == NULL) | |
b511e0d0 | 635 | fatal("cipher_get_keycontext: no 3des context"); |
905081a4 | 636 | plen = EVP_X_STATE_LEN(desc->k1); |
637 | if (dat == NULL) | |
638 | return (3*plen); | |
639 | memcpy(dat, EVP_X_STATE(desc->k1), plen); | |
640 | memcpy(dat + plen, EVP_X_STATE(desc->k2), plen); | |
641 | memcpy(dat + 2*plen, EVP_X_STATE(desc->k3), plen); | |
642 | return (3*plen); | |
643 | } | |
644 | ||
645 | /* Generic EVP */ | |
646 | plen = EVP_X_STATE_LEN(cc->evp); | |
647 | if (dat == NULL) | |
648 | return (plen); | |
649 | ||
650 | memcpy(dat, EVP_X_STATE(cc->evp), plen); | |
651 | return (plen); | |
652 | } | |
653 | ||
654 | void | |
655 | cipher_set_keycontext(CipherContext *cc, u_char *dat) | |
656 | { | |
657 | Cipher *c = cc->cipher; | |
658 | int plen; | |
659 | ||
660 | if (c->number == SSH_CIPHER_3DES) { | |
661 | struct ssh1_3des_ctx *desc; | |
662 | desc = EVP_CIPHER_CTX_get_app_data(&cc->evp); | |
663 | if (desc == NULL) | |
b511e0d0 | 664 | fatal("cipher_set_keycontext: no 3des context"); |
905081a4 | 665 | plen = EVP_X_STATE_LEN(desc->k1); |
666 | memcpy(EVP_X_STATE(desc->k1), dat, plen); | |
667 | memcpy(EVP_X_STATE(desc->k2), dat + plen, plen); | |
668 | memcpy(EVP_X_STATE(desc->k3), dat + 2*plen, plen); | |
669 | } else { | |
670 | plen = EVP_X_STATE_LEN(cc->evp); | |
671 | memcpy(EVP_X_STATE(cc->evp), dat, plen); | |
672 | } | |
673 | } |