Annotation of src/usr.bin/ssh/cipher.c, Revision 1.93
1.93 ! markus 1: /* $OpenBSD: cipher.c,v 1.92 2013/12/02 03:13:14 djm Exp $ */
1.1 deraadt 2: /*
1.30 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.26 markus 6: *
1.30 deraadt 7: * As far as I am concerned, the code I have written for this software
8: * can be used freely for any purpose. Any derived versions of this
9: * software must be clearly marked as such, and if the derived work is
10: * incompatible with the protocol description in the RFC file, it must be
11: * called by a name other than "ssh" or "Secure Shell".
1.26 markus 12: *
13: *
1.30 deraadt 14: * Copyright (c) 1999 Niels Provos. All rights reserved.
1.46 markus 15: * Copyright (c) 1999, 2000 Markus Friedl. All rights reserved.
1.26 markus 16: *
1.30 deraadt 17: * Redistribution and use in source and binary forms, with or without
18: * modification, are permitted provided that the following conditions
19: * are met:
20: * 1. Redistributions of source code must retain the above copyright
21: * notice, this list of conditions and the following disclaimer.
22: * 2. Redistributions in binary form must reproduce the above copyright
23: * notice, this list of conditions and the following disclaimer in the
24: * documentation and/or other materials provided with the distribution.
1.26 markus 25: *
1.30 deraadt 26: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.17 deraadt 36: */
1.1 deraadt 37:
1.81 deraadt 38: #include <sys/types.h>
1.1 deraadt 39:
1.80 stevesk 40: #include <openssl/md5.h>
41:
42: #include <string.h>
1.81 deraadt 43: #include <stdarg.h>
1.91 djm 44: #include <stdio.h>
1.80 stevesk 45:
1.24 markus 46: #include "xmalloc.h"
1.42 markus 47: #include "log.h"
1.91 djm 48: #include "misc.h"
1.42 markus 49: #include "cipher.h"
1.57 markus 50:
1.64 markus 51: extern const EVP_CIPHER *evp_ssh1_bf(void);
52: extern const EVP_CIPHER *evp_ssh1_3des(void);
53: extern void ssh1_3des_iv(EVP_CIPHER_CTX *, int, u_char *, int);
1.1 deraadt 54:
1.51 markus 55: struct Cipher {
56: char *name;
57: int number; /* for ssh1 only */
58: u_int block_size;
59: u_int key_len;
1.85 markus 60: u_int iv_len; /* defaults to block_size */
61: u_int auth_len;
1.74 djm 62: u_int discard_len;
1.91 djm 63: u_int flags;
64: #define CFLAG_CBC (1<<0)
65: #define CFLAG_CHACHAPOLY (1<<1)
1.56 markus 66: const EVP_CIPHER *(*evptype)(void);
1.88 djm 67: };
68:
69: static const struct Cipher ciphers[] = {
1.85 markus 70: { "none", SSH_CIPHER_NONE, 8, 0, 0, 0, 0, 0, EVP_enc_null },
71: { "des", SSH_CIPHER_DES, 8, 8, 0, 0, 0, 1, EVP_des_cbc },
72: { "3des", SSH_CIPHER_3DES, 8, 16, 0, 0, 0, 1, evp_ssh1_3des },
73: { "blowfish", SSH_CIPHER_BLOWFISH, 8, 32, 0, 0, 0, 1, evp_ssh1_bf },
74:
75: { "3des-cbc", SSH_CIPHER_SSH2, 8, 24, 0, 0, 0, 1, EVP_des_ede3_cbc },
76: { "blowfish-cbc",
77: SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_bf_cbc },
78: { "cast128-cbc",
79: SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_cast5_cbc },
80: { "arcfour", SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 0, EVP_rc4 },
81: { "arcfour128", SSH_CIPHER_SSH2, 8, 16, 0, 0, 1536, 0, EVP_rc4 },
82: { "arcfour256", SSH_CIPHER_SSH2, 8, 32, 0, 0, 1536, 0, EVP_rc4 },
83: { "aes128-cbc", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 1, EVP_aes_128_cbc },
84: { "aes192-cbc", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 1, EVP_aes_192_cbc },
85: { "aes256-cbc", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
1.57 markus 86: { "rijndael-cbc@lysator.liu.se",
1.85 markus 87: SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
88: { "aes128-ctr", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 0, EVP_aes_128_ctr },
89: { "aes192-ctr", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 0, EVP_aes_192_ctr },
90: { "aes256-ctr", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 0, EVP_aes_256_ctr },
91: { "aes128-gcm@openssh.com",
92: SSH_CIPHER_SSH2, 16, 16, 12, 16, 0, 0, EVP_aes_128_gcm },
93: { "aes256-gcm@openssh.com",
94: SSH_CIPHER_SSH2, 16, 32, 12, 16, 0, 0, EVP_aes_256_gcm },
1.91 djm 95: { "chacha20-poly1305@openssh.com",
96: SSH_CIPHER_SSH2, 8, 64, 0, 16, 0, CFLAG_CHACHAPOLY, NULL },
1.47 markus 97:
1.85 markus 98: { NULL, SSH_CIPHER_INVALID, 0, 0, 0, 0, 0, 0, NULL }
1.32 markus 99: };
100:
101: /*--*/
1.1 deraadt 102:
1.90 dtucker 103: /* Returns a list of supported ciphers separated by the specified char. */
1.88 djm 104: char *
1.91 djm 105: cipher_alg_list(char sep, int auth_only)
1.88 djm 106: {
107: char *ret = NULL;
108: size_t nlen, rlen = 0;
109: const Cipher *c;
110:
111: for (c = ciphers; c->name != NULL; c++) {
112: if (c->number != SSH_CIPHER_SSH2)
113: continue;
1.91 djm 114: if (auth_only && c->auth_len == 0)
115: continue;
1.88 djm 116: if (ret != NULL)
1.90 dtucker 117: ret[rlen++] = sep;
1.88 djm 118: nlen = strlen(c->name);
119: ret = xrealloc(ret, 1, rlen + nlen + 2);
120: memcpy(ret + rlen, c->name, nlen + 1);
121: rlen += nlen;
122: }
123: return ret;
124: }
125:
1.54 markus 126: u_int
1.66 jakob 127: cipher_blocksize(const Cipher *c)
1.51 markus 128: {
129: return (c->block_size);
130: }
1.60 deraadt 131:
1.54 markus 132: u_int
1.66 jakob 133: cipher_keylen(const Cipher *c)
1.51 markus 134: {
135: return (c->key_len);
136: }
1.60 deraadt 137:
1.54 markus 138: u_int
1.85 markus 139: cipher_authlen(const Cipher *c)
140: {
141: return (c->auth_len);
142: }
143:
144: u_int
145: cipher_ivlen(const Cipher *c)
146: {
1.91 djm 147: /*
148: * Default is cipher block size, except for chacha20+poly1305 that
149: * needs no IV. XXX make iv_len == -1 default?
150: */
151: return (c->iv_len != 0 || (c->flags & CFLAG_CHACHAPOLY) != 0) ?
152: c->iv_len : c->block_size;
1.85 markus 153: }
154:
155: u_int
1.66 jakob 156: cipher_get_number(const Cipher *c)
1.53 markus 157: {
158: return (c->number);
1.82 markus 159: }
160:
161: u_int
162: cipher_is_cbc(const Cipher *c)
163: {
1.91 djm 164: return (c->flags & CFLAG_CBC) != 0;
1.53 markus 165: }
1.51 markus 166:
1.41 markus 167: u_int
1.34 markus 168: cipher_mask_ssh1(int client)
1.1 deraadt 169: {
1.41 markus 170: u_int mask = 0;
1.48 deraadt 171: mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
1.34 markus 172: mask |= 1 << SSH_CIPHER_BLOWFISH;
173: if (client) {
174: mask |= 1 << SSH_CIPHER_DES;
1.32 markus 175: }
176: return mask;
1.1 deraadt 177: }
178:
1.88 djm 179: const Cipher *
1.32 markus 180: cipher_by_name(const char *name)
181: {
1.88 djm 182: const Cipher *c;
1.32 markus 183: for (c = ciphers; c->name != NULL; c++)
1.73 djm 184: if (strcmp(c->name, name) == 0)
1.32 markus 185: return c;
186: return NULL;
187: }
188:
1.88 djm 189: const Cipher *
1.32 markus 190: cipher_by_number(int id)
191: {
1.88 djm 192: const Cipher *c;
1.32 markus 193: for (c = ciphers; c->name != NULL; c++)
194: if (c->number == id)
195: return c;
196: return NULL;
197: }
1.24 markus 198:
199: #define CIPHER_SEP ","
200: int
201: ciphers_valid(const char *names)
202: {
1.88 djm 203: const Cipher *c;
1.69 avsm 204: char *cipher_list, *cp;
1.24 markus 205: char *p;
206:
1.27 markus 207: if (names == NULL || strcmp(names, "") == 0)
1.24 markus 208: return 0;
1.69 avsm 209: cipher_list = cp = xstrdup(names);
1.32 markus 210: for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
1.48 deraadt 211: (p = strsep(&cp, CIPHER_SEP))) {
1.32 markus 212: c = cipher_by_name(p);
213: if (c == NULL || c->number != SSH_CIPHER_SSH2) {
214: debug("bad cipher %s [%s]", p, names);
1.89 djm 215: free(cipher_list);
1.24 markus 216: return 0;
1.32 markus 217: } else {
1.36 markus 218: debug3("cipher ok: %s [%s]", p, names);
1.24 markus 219: }
220: }
1.36 markus 221: debug3("ciphers ok: [%s]", names);
1.89 djm 222: free(cipher_list);
1.24 markus 223: return 1;
224: }
225:
1.18 markus 226: /*
227: * Parses the name of the cipher. Returns the number of the corresponding
228: * cipher, or -1 on error.
229: */
1.1 deraadt 230:
1.4 provos 231: int
232: cipher_number(const char *name)
1.1 deraadt 233: {
1.88 djm 234: const Cipher *c;
1.27 markus 235: if (name == NULL)
236: return -1;
1.73 djm 237: for (c = ciphers; c->name != NULL; c++)
238: if (strcasecmp(c->name, name) == 0)
239: return c->number;
240: return -1;
1.1 deraadt 241: }
242:
1.32 markus 243: char *
244: cipher_name(int id)
1.1 deraadt 245: {
1.88 djm 246: const Cipher *c = cipher_by_number(id);
1.32 markus 247: return (c==NULL) ? "<unknown>" : c->name;
1.1 deraadt 248: }
249:
1.26 markus 250: void
1.88 djm 251: cipher_init(CipherContext *cc, const Cipher *cipher,
1.52 markus 252: const u_char *key, u_int keylen, const u_char *iv, u_int ivlen,
1.69 avsm 253: int do_encrypt)
1.16 markus 254: {
1.52 markus 255: static int dowarn = 1;
256: const EVP_CIPHER *type;
257: int klen;
1.74 djm 258: u_char *junk, *discard;
1.52 markus 259:
260: if (cipher->number == SSH_CIPHER_DES) {
261: if (dowarn) {
262: error("Warning: use of DES is strongly discouraged "
263: "due to cryptographic weaknesses");
264: dowarn = 0;
265: }
266: if (keylen > 8)
267: keylen = 8;
268: }
269: cc->plaintext = (cipher->number == SSH_CIPHER_NONE);
1.85 markus 270: cc->encrypt = do_encrypt;
1.52 markus 271:
1.32 markus 272: if (keylen < cipher->key_len)
273: fatal("cipher_init: key length %d is insufficient for %s.",
274: keylen, cipher->name);
1.85 markus 275: if (iv != NULL && ivlen < cipher_ivlen(cipher))
1.32 markus 276: fatal("cipher_init: iv length %d is insufficient for %s.",
277: ivlen, cipher->name);
278: cc->cipher = cipher;
1.52 markus 279:
1.91 djm 280: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
281: chachapoly_init(&cc->cp_ctx, key, keylen);
282: return;
283: }
1.52 markus 284: type = (*cipher->evptype)();
285: EVP_CIPHER_CTX_init(&cc->evp);
286: if (EVP_CipherInit(&cc->evp, type, NULL, (u_char *)iv,
1.69 avsm 287: (do_encrypt == CIPHER_ENCRYPT)) == 0)
1.52 markus 288: fatal("cipher_init: EVP_CipherInit failed for %s",
289: cipher->name);
1.85 markus 290: if (cipher_authlen(cipher) &&
291: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_SET_IV_FIXED,
292: -1, (u_char *)iv))
293: fatal("cipher_init: EVP_CTRL_GCM_SET_IV_FIXED failed for %s",
294: cipher->name);
1.52 markus 295: klen = EVP_CIPHER_CTX_key_length(&cc->evp);
1.76 djm 296: if (klen > 0 && keylen != (u_int)klen) {
1.62 markus 297: debug2("cipher_init: set keylen (%d -> %d)", klen, keylen);
1.52 markus 298: if (EVP_CIPHER_CTX_set_key_length(&cc->evp, keylen) == 0)
299: fatal("cipher_init: set keylen failed (%d -> %d)",
300: klen, keylen);
301: }
302: if (EVP_CipherInit(&cc->evp, NULL, (u_char *)key, NULL, -1) == 0)
303: fatal("cipher_init: EVP_CipherInit: set key failed for %s",
304: cipher->name);
1.74 djm 305:
1.77 djm 306: if (cipher->discard_len > 0) {
1.74 djm 307: junk = xmalloc(cipher->discard_len);
308: discard = xmalloc(cipher->discard_len);
309: if (EVP_Cipher(&cc->evp, discard, junk,
310: cipher->discard_len) == 0)
311: fatal("evp_crypt: EVP_Cipher failed during discard");
312: memset(discard, 0, cipher->discard_len);
1.89 djm 313: free(junk);
314: free(discard);
1.74 djm 315: }
1.1 deraadt 316: }
1.21 markus 317:
1.83 markus 318: /*
319: * cipher_crypt() operates as following:
320: * Copy 'aadlen' bytes (without en/decryption) from 'src' to 'dest'.
321: * Theses bytes are treated as additional authenticated data for
322: * authenticated encryption modes.
323: * En/Decrypt 'len' bytes at offset 'aadlen' from 'src' to 'dest'.
1.85 markus 324: * Use 'authlen' bytes at offset 'len'+'aadlen' as the authentication tag.
325: * This tag is written on encryption and verified on decryption.
1.83 markus 326: * Both 'aadlen' and 'authlen' can be set to 0.
1.93 ! markus 327: * cipher_crypt() returns 0 on success and -1 if the decryption integrity
! 328: * check fails.
1.83 markus 329: */
1.93 ! markus 330: int
1.91 djm 331: cipher_crypt(CipherContext *cc, u_int seqnr, u_char *dest, const u_char *src,
1.85 markus 332: u_int len, u_int aadlen, u_int authlen)
1.32 markus 333: {
1.93 ! markus 334: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
! 335: return chachapoly_crypt(&cc->cp_ctx, seqnr, dest, src, len,
! 336: aadlen, authlen, cc->encrypt);
1.85 markus 337: if (authlen) {
338: u_char lastiv[1];
339:
340: if (authlen != cipher_authlen(cc->cipher))
341: fatal("%s: authlen mismatch %d", __func__, authlen);
342: /* increment IV */
343: if (!EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_IV_GEN,
344: 1, lastiv))
345: fatal("%s: EVP_CTRL_GCM_IV_GEN", __func__);
346: /* set tag on decyption */
347: if (!cc->encrypt &&
348: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_SET_TAG,
349: authlen, (u_char *)src + aadlen + len))
350: fatal("%s: EVP_CTRL_GCM_SET_TAG", __func__);
351: }
352: if (aadlen) {
353: if (authlen &&
354: EVP_Cipher(&cc->evp, NULL, (u_char *)src, aadlen) < 0)
355: fatal("%s: EVP_Cipher(aad) failed", __func__);
1.83 markus 356: memcpy(dest, src, aadlen);
1.85 markus 357: }
1.32 markus 358: if (len % cc->cipher->block_size)
1.83 markus 359: fatal("%s: bad plaintext length %d", __func__, len);
360: if (EVP_Cipher(&cc->evp, dest + aadlen, (u_char *)src + aadlen,
361: len) < 0)
362: fatal("%s: EVP_Cipher failed", __func__);
1.85 markus 363: if (authlen) {
364: /* compute tag (on encrypt) or verify tag (on decrypt) */
1.86 djm 365: if (EVP_Cipher(&cc->evp, NULL, NULL, 0) < 0) {
366: if (cc->encrypt)
367: fatal("%s: EVP_Cipher(final) failed", __func__);
368: else
1.93 ! markus 369: return -1;
1.86 djm 370: }
1.85 markus 371: if (cc->encrypt &&
372: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_GET_TAG,
373: authlen, dest + aadlen + len))
374: fatal("%s: EVP_CTRL_GCM_GET_TAG", __func__);
375: }
1.93 ! markus 376: return 0;
1.21 markus 377: }
378:
1.91 djm 379: /* Extract the packet length, including any decryption necessary beforehand */
380: int
381: cipher_get_length(CipherContext *cc, u_int *plenp, u_int seqnr,
382: const u_char *cp, u_int len)
383: {
384: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
385: return chachapoly_get_length(&cc->cp_ctx, plenp, seqnr,
386: cp, len);
387: if (len < 4)
388: return -1;
389: *plenp = get_u32(cp);
390: return 0;
391: }
392:
1.26 markus 393: void
1.51 markus 394: cipher_cleanup(CipherContext *cc)
1.16 markus 395: {
1.91 djm 396: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
1.92 djm 397: memset(&cc->cp_ctx, 0, sizeof(cc->cp_ctx));
1.91 djm 398: else if (EVP_CIPHER_CTX_cleanup(&cc->evp) == 0)
1.52 markus 399: error("cipher_cleanup: EVP_CIPHER_CTX_cleanup failed");
1.16 markus 400: }
1.1 deraadt 401:
1.32 markus 402: /*
403: * Selects the cipher, and keys if by computing the MD5 checksum of the
404: * passphrase and using the resulting 16 bytes as the key.
405: */
1.1 deraadt 406:
1.26 markus 407: void
1.88 djm 408: cipher_set_key_string(CipherContext *cc, const Cipher *cipher,
1.69 avsm 409: const char *passphrase, int do_encrypt)
1.16 markus 410: {
1.32 markus 411: MD5_CTX md;
1.41 markus 412: u_char digest[16];
1.32 markus 413:
414: MD5_Init(&md);
415: MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase));
416: MD5_Final(digest, &md);
1.16 markus 417:
1.69 avsm 418: cipher_init(cc, cipher, digest, 16, NULL, 0, do_encrypt);
1.16 markus 419:
1.32 markus 420: memset(digest, 0, sizeof(digest));
421: memset(&md, 0, sizeof(md));
1.52 markus 422: }
1.53 markus 423:
1.54 markus 424: /*
1.53 markus 425: * Exports an IV from the CipherContext required to export the key
426: * state back from the unprivileged child to the privileged parent
427: * process.
428: */
429:
430: int
1.66 jakob 431: cipher_get_keyiv_len(const CipherContext *cc)
1.53 markus 432: {
1.88 djm 433: const Cipher *c = cc->cipher;
1.53 markus 434: int ivlen;
435:
436: if (c->number == SSH_CIPHER_3DES)
437: ivlen = 24;
1.91 djm 438: else if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
439: ivlen = 0;
1.53 markus 440: else
441: ivlen = EVP_CIPHER_CTX_iv_length(&cc->evp);
442: return (ivlen);
443: }
444:
445: void
446: cipher_get_keyiv(CipherContext *cc, u_char *iv, u_int len)
447: {
1.88 djm 448: const Cipher *c = cc->cipher;
1.53 markus 449: int evplen;
450:
1.91 djm 451: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
452: if (len != 0)
453: fatal("%s: wrong iv length %d != %d", __func__, len, 0);
454: return;
455: }
456:
1.53 markus 457: switch (c->number) {
458: case SSH_CIPHER_SSH2:
459: case SSH_CIPHER_DES:
460: case SSH_CIPHER_BLOWFISH:
461: evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
1.76 djm 462: if (evplen <= 0)
1.53 markus 463: return;
1.76 djm 464: if ((u_int)evplen != len)
1.58 markus 465: fatal("%s: wrong iv length %d != %d", __func__,
1.53 markus 466: evplen, len);
1.85 markus 467: if (cipher_authlen(c)) {
468: if (!EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_IV_GEN,
469: len, iv))
470: fatal("%s: EVP_CTRL_GCM_IV_GEN", __func__);
471: } else
472: memcpy(iv, cc->evp.iv, len);
1.63 markus 473: break;
474: case SSH_CIPHER_3DES:
475: ssh1_3des_iv(&cc->evp, 0, iv, 24);
1.53 markus 476: break;
477: default:
1.58 markus 478: fatal("%s: bad cipher %d", __func__, c->number);
1.53 markus 479: }
480: }
481:
482: void
483: cipher_set_keyiv(CipherContext *cc, u_char *iv)
484: {
1.88 djm 485: const Cipher *c = cc->cipher;
1.53 markus 486: int evplen = 0;
1.91 djm 487:
488: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
489: return;
1.53 markus 490:
491: switch (c->number) {
492: case SSH_CIPHER_SSH2:
493: case SSH_CIPHER_DES:
494: case SSH_CIPHER_BLOWFISH:
495: evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
496: if (evplen == 0)
497: return;
1.85 markus 498: if (cipher_authlen(c)) {
499: if (!EVP_CIPHER_CTX_ctrl(&cc->evp,
500: EVP_CTRL_GCM_SET_IV_FIXED, -1, iv))
501: fatal("%s: EVP_CTRL_GCM_SET_IV_FIXED failed",
502: __func__);
503: } else
504: memcpy(cc->evp.iv, iv, evplen);
1.63 markus 505: break;
506: case SSH_CIPHER_3DES:
507: ssh1_3des_iv(&cc->evp, 1, iv, 24);
1.53 markus 508: break;
509: default:
1.58 markus 510: fatal("%s: bad cipher %d", __func__, c->number);
1.53 markus 511: }
512: }
513:
514: #define EVP_X_STATE(evp) (evp).cipher_data
515: #define EVP_X_STATE_LEN(evp) (evp).cipher->ctx_size
516:
517: int
1.66 jakob 518: cipher_get_keycontext(const CipherContext *cc, u_char *dat)
1.53 markus 519: {
1.88 djm 520: const Cipher *c = cc->cipher;
1.59 markus 521: int plen = 0;
1.53 markus 522:
1.87 djm 523: if (c->evptype == EVP_rc4) {
1.59 markus 524: plen = EVP_X_STATE_LEN(cc->evp);
1.53 markus 525: if (dat == NULL)
1.59 markus 526: return (plen);
527: memcpy(dat, EVP_X_STATE(cc->evp), plen);
1.53 markus 528: }
529: return (plen);
530: }
531:
532: void
533: cipher_set_keycontext(CipherContext *cc, u_char *dat)
534: {
1.88 djm 535: const Cipher *c = cc->cipher;
1.53 markus 536: int plen;
537:
1.87 djm 538: if (c->evptype == EVP_rc4) {
1.53 markus 539: plen = EVP_X_STATE_LEN(cc->evp);
540: memcpy(EVP_X_STATE(cc->evp), dat, plen);
541: }
1.1 deraadt 542: }