Annotation of src/usr.bin/ssh/cipher.c, Revision 1.113
1.113 ! djm 1: /* $OpenBSD: cipher.c,v 1.112 2018/09/13 02:08:33 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 <string.h>
1.81 deraadt 41: #include <stdarg.h>
1.91 djm 42: #include <stdio.h>
1.80 stevesk 43:
1.99 djm 44: #include "cipher.h"
1.91 djm 45: #include "misc.h"
1.99 djm 46: #include "sshbuf.h"
47: #include "ssherr.h"
1.95 markus 48: #include "digest.h"
1.57 markus 49:
1.113 ! djm 50: #ifndef WITH_OPENSSL
! 51: #define EVP_CIPHER_CTX void
! 52: #endif
1.1 deraadt 53:
1.102 djm 54: struct sshcipher_ctx {
55: int plaintext;
56: int encrypt;
57: EVP_CIPHER_CTX *evp;
58: struct chachapoly_ctx cp_ctx; /* XXX union with evp? */
59: struct aesctr_ctx ac_ctx; /* XXX union with evp? */
60: const struct sshcipher *cipher;
61: };
62:
1.99 djm 63: struct sshcipher {
1.51 markus 64: char *name;
65: u_int block_size;
66: u_int key_len;
1.85 markus 67: u_int iv_len; /* defaults to block_size */
68: u_int auth_len;
1.91 djm 69: u_int flags;
70: #define CFLAG_CBC (1<<0)
71: #define CFLAG_CHACHAPOLY (1<<1)
1.98 markus 72: #define CFLAG_AESCTR (1<<2)
73: #define CFLAG_NONE (1<<3)
1.104 djm 74: #define CFLAG_INTERNAL CFLAG_NONE /* Don't use "none" for packets */
1.98 markus 75: #ifdef WITH_OPENSSL
1.56 markus 76: const EVP_CIPHER *(*evptype)(void);
1.98 markus 77: #else
78: void *ignored;
79: #endif
1.88 djm 80: };
81:
1.99 djm 82: static const struct sshcipher ciphers[] = {
1.98 markus 83: #ifdef WITH_OPENSSL
1.107 djm 84: { "3des-cbc", 8, 24, 0, 0, CFLAG_CBC, EVP_des_ede3_cbc },
85: { "aes128-cbc", 16, 16, 0, 0, CFLAG_CBC, EVP_aes_128_cbc },
86: { "aes192-cbc", 16, 24, 0, 0, CFLAG_CBC, EVP_aes_192_cbc },
87: { "aes256-cbc", 16, 32, 0, 0, CFLAG_CBC, EVP_aes_256_cbc },
1.57 markus 88: { "rijndael-cbc@lysator.liu.se",
1.107 djm 89: 16, 32, 0, 0, CFLAG_CBC, EVP_aes_256_cbc },
90: { "aes128-ctr", 16, 16, 0, 0, 0, EVP_aes_128_ctr },
91: { "aes192-ctr", 16, 24, 0, 0, 0, EVP_aes_192_ctr },
92: { "aes256-ctr", 16, 32, 0, 0, 0, EVP_aes_256_ctr },
1.85 markus 93: { "aes128-gcm@openssh.com",
1.107 djm 94: 16, 16, 12, 16, 0, EVP_aes_128_gcm },
1.85 markus 95: { "aes256-gcm@openssh.com",
1.107 djm 96: 16, 32, 12, 16, 0, EVP_aes_256_gcm },
1.98 markus 97: #else
1.107 djm 98: { "aes128-ctr", 16, 16, 0, 0, CFLAG_AESCTR, NULL },
99: { "aes192-ctr", 16, 24, 0, 0, CFLAG_AESCTR, NULL },
100: { "aes256-ctr", 16, 32, 0, 0, CFLAG_AESCTR, NULL },
1.98 markus 101: #endif
1.91 djm 102: { "chacha20-poly1305@openssh.com",
1.107 djm 103: 8, 64, 0, 16, CFLAG_CHACHAPOLY, NULL },
104: { "none", 8, 0, 0, 0, CFLAG_NONE, NULL },
1.47 markus 105:
1.107 djm 106: { NULL, 0, 0, 0, 0, 0, NULL }
1.32 markus 107: };
108:
109: /*--*/
1.1 deraadt 110:
1.99 djm 111: /* Returns a comma-separated list of supported ciphers. */
1.88 djm 112: char *
1.91 djm 113: cipher_alg_list(char sep, int auth_only)
1.88 djm 114: {
1.99 djm 115: char *tmp, *ret = NULL;
1.88 djm 116: size_t nlen, rlen = 0;
1.99 djm 117: const struct sshcipher *c;
1.88 djm 118:
119: for (c = ciphers; c->name != NULL; c++) {
1.104 djm 120: if ((c->flags & CFLAG_INTERNAL) != 0)
1.88 djm 121: continue;
1.91 djm 122: if (auth_only && c->auth_len == 0)
123: continue;
1.88 djm 124: if (ret != NULL)
1.90 dtucker 125: ret[rlen++] = sep;
1.88 djm 126: nlen = strlen(c->name);
1.99 djm 127: if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
128: free(ret);
129: return NULL;
130: }
131: ret = tmp;
1.88 djm 132: memcpy(ret + rlen, c->name, nlen + 1);
133: rlen += nlen;
134: }
135: return ret;
136: }
137:
1.54 markus 138: u_int
1.99 djm 139: cipher_blocksize(const struct sshcipher *c)
1.51 markus 140: {
141: return (c->block_size);
142: }
1.60 deraadt 143:
1.54 markus 144: u_int
1.99 djm 145: cipher_keylen(const struct sshcipher *c)
1.51 markus 146: {
147: return (c->key_len);
1.94 dtucker 148: }
149:
150: u_int
1.99 djm 151: cipher_seclen(const struct sshcipher *c)
1.94 dtucker 152: {
153: if (strcmp("3des-cbc", c->name) == 0)
154: return 14;
155: return cipher_keylen(c);
1.51 markus 156: }
1.60 deraadt 157:
1.54 markus 158: u_int
1.99 djm 159: cipher_authlen(const struct sshcipher *c)
1.85 markus 160: {
161: return (c->auth_len);
162: }
163:
164: u_int
1.99 djm 165: cipher_ivlen(const struct sshcipher *c)
1.85 markus 166: {
1.91 djm 167: /*
168: * Default is cipher block size, except for chacha20+poly1305 that
169: * needs no IV. XXX make iv_len == -1 default?
170: */
171: return (c->iv_len != 0 || (c->flags & CFLAG_CHACHAPOLY) != 0) ?
172: c->iv_len : c->block_size;
1.85 markus 173: }
174:
175: u_int
1.99 djm 176: cipher_is_cbc(const struct sshcipher *c)
1.82 markus 177: {
1.91 djm 178: return (c->flags & CFLAG_CBC) != 0;
1.53 markus 179: }
1.51 markus 180:
1.41 markus 181: u_int
1.102 djm 182: cipher_ctx_is_plaintext(struct sshcipher_ctx *cc)
183: {
184: return cc->plaintext;
185: }
186:
1.99 djm 187: const struct sshcipher *
1.32 markus 188: cipher_by_name(const char *name)
189: {
1.99 djm 190: const struct sshcipher *c;
1.32 markus 191: for (c = ciphers; c->name != NULL; c++)
1.73 djm 192: if (strcmp(c->name, name) == 0)
1.32 markus 193: return c;
194: return NULL;
195: }
196:
1.24 markus 197: #define CIPHER_SEP ","
198: int
199: ciphers_valid(const char *names)
200: {
1.99 djm 201: const struct sshcipher *c;
1.69 avsm 202: char *cipher_list, *cp;
1.24 markus 203: char *p;
204:
1.27 markus 205: if (names == NULL || strcmp(names, "") == 0)
1.24 markus 206: return 0;
1.99 djm 207: if ((cipher_list = cp = strdup(names)) == NULL)
208: return 0;
1.32 markus 209: for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
1.48 deraadt 210: (p = strsep(&cp, CIPHER_SEP))) {
1.32 markus 211: c = cipher_by_name(p);
1.104 djm 212: if (c == NULL || (c->flags & CFLAG_INTERNAL) != 0) {
1.89 djm 213: free(cipher_list);
1.24 markus 214: return 0;
215: }
216: }
1.89 djm 217: free(cipher_list);
1.24 markus 218: return 1;
219: }
220:
1.99 djm 221: const char *
222: cipher_warning_message(const struct sshcipher_ctx *cc)
223: {
224: if (cc == NULL || cc->cipher == NULL)
225: return NULL;
1.104 djm 226: /* XXX repurpose for CBC warning */
1.99 djm 227: return NULL;
228: }
229:
230: int
1.102 djm 231: cipher_init(struct sshcipher_ctx **ccp, const struct sshcipher *cipher,
1.52 markus 232: const u_char *key, u_int keylen, const u_char *iv, u_int ivlen,
1.69 avsm 233: int do_encrypt)
1.16 markus 234: {
1.102 djm 235: struct sshcipher_ctx *cc = NULL;
236: int ret = SSH_ERR_INTERNAL_ERROR;
1.98 markus 237: #ifdef WITH_OPENSSL
1.52 markus 238: const EVP_CIPHER *type;
239: int klen;
1.102 djm 240: #endif
241:
242: *ccp = NULL;
243: if ((cc = calloc(sizeof(*cc), 1)) == NULL)
244: return SSH_ERR_ALLOC_FAIL;
1.52 markus 245:
1.105 djm 246: cc->plaintext = (cipher->flags & CFLAG_NONE) != 0;
1.85 markus 247: cc->encrypt = do_encrypt;
1.52 markus 248:
1.99 djm 249: if (keylen < cipher->key_len ||
1.102 djm 250: (iv != NULL && ivlen < cipher_ivlen(cipher))) {
251: ret = SSH_ERR_INVALID_ARGUMENT;
252: goto out;
253: }
1.99 djm 254:
1.32 markus 255: cc->cipher = cipher;
1.91 djm 256: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
1.102 djm 257: ret = chachapoly_init(&cc->cp_ctx, key, keylen);
258: goto out;
1.91 djm 259: }
1.104 djm 260: if ((cc->cipher->flags & CFLAG_NONE) != 0) {
261: ret = 0;
262: goto out;
263: }
1.98 markus 264: #ifndef WITH_OPENSSL
265: if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
266: aesctr_keysetup(&cc->ac_ctx, key, 8 * keylen, 8 * ivlen);
267: aesctr_ivsetup(&cc->ac_ctx, iv);
1.102 djm 268: ret = 0;
269: goto out;
270: }
271: ret = SSH_ERR_INVALID_ARGUMENT;
272: goto out;
273: #else /* WITH_OPENSSL */
1.52 markus 274: type = (*cipher->evptype)();
1.102 djm 275: if ((cc->evp = EVP_CIPHER_CTX_new()) == NULL) {
276: ret = SSH_ERR_ALLOC_FAIL;
277: goto out;
278: }
279: if (EVP_CipherInit(cc->evp, type, NULL, (u_char *)iv,
1.99 djm 280: (do_encrypt == CIPHER_ENCRYPT)) == 0) {
281: ret = SSH_ERR_LIBCRYPTO_ERROR;
1.102 djm 282: goto out;
1.99 djm 283: }
1.85 markus 284: if (cipher_authlen(cipher) &&
1.102 djm 285: !EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_SET_IV_FIXED,
1.99 djm 286: -1, (u_char *)iv)) {
287: ret = SSH_ERR_LIBCRYPTO_ERROR;
1.102 djm 288: goto out;
1.99 djm 289: }
1.102 djm 290: klen = EVP_CIPHER_CTX_key_length(cc->evp);
1.76 djm 291: if (klen > 0 && keylen != (u_int)klen) {
1.102 djm 292: if (EVP_CIPHER_CTX_set_key_length(cc->evp, keylen) == 0) {
1.99 djm 293: ret = SSH_ERR_LIBCRYPTO_ERROR;
1.102 djm 294: goto out;
1.99 djm 295: }
296: }
1.102 djm 297: if (EVP_CipherInit(cc->evp, NULL, (u_char *)key, NULL, -1) == 0) {
1.99 djm 298: ret = SSH_ERR_LIBCRYPTO_ERROR;
1.102 djm 299: goto out;
1.99 djm 300: }
1.102 djm 301: ret = 0;
302: #endif /* WITH_OPENSSL */
303: out:
304: if (ret == 0) {
305: /* success */
306: *ccp = cc;
307: } else {
308: if (cc != NULL) {
309: #ifdef WITH_OPENSSL
1.109 jsing 310: EVP_CIPHER_CTX_free(cc->evp);
1.102 djm 311: #endif /* WITH_OPENSSL */
312: explicit_bzero(cc, sizeof(*cc));
313: free(cc);
1.99 djm 314: }
1.74 djm 315: }
1.102 djm 316: return ret;
1.1 deraadt 317: }
1.21 markus 318:
1.83 markus 319: /*
320: * cipher_crypt() operates as following:
321: * Copy 'aadlen' bytes (without en/decryption) from 'src' to 'dest'.
322: * Theses bytes are treated as additional authenticated data for
323: * authenticated encryption modes.
324: * En/Decrypt 'len' bytes at offset 'aadlen' from 'src' to 'dest'.
1.85 markus 325: * Use 'authlen' bytes at offset 'len'+'aadlen' as the authentication tag.
326: * This tag is written on encryption and verified on decryption.
1.83 markus 327: * Both 'aadlen' and 'authlen' can be set to 0.
328: */
1.93 markus 329: int
1.99 djm 330: cipher_crypt(struct sshcipher_ctx *cc, u_int seqnr, u_char *dest,
331: const u_char *src, u_int len, u_int aadlen, u_int authlen)
1.32 markus 332: {
1.99 djm 333: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
334: return chachapoly_crypt(&cc->cp_ctx, seqnr, dest, src,
335: len, aadlen, authlen, cc->encrypt);
336: }
1.104 djm 337: if ((cc->cipher->flags & CFLAG_NONE) != 0) {
338: memcpy(dest, src, aadlen + len);
339: return 0;
340: }
1.98 markus 341: #ifndef WITH_OPENSSL
342: if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
343: if (aadlen)
344: memcpy(dest, src, aadlen);
345: aesctr_encrypt_bytes(&cc->ac_ctx, src + aadlen,
346: dest + aadlen, len);
347: return 0;
348: }
1.99 djm 349: return SSH_ERR_INVALID_ARGUMENT;
1.98 markus 350: #else
1.85 markus 351: if (authlen) {
352: u_char lastiv[1];
353:
354: if (authlen != cipher_authlen(cc->cipher))
1.99 djm 355: return SSH_ERR_INVALID_ARGUMENT;
1.85 markus 356: /* increment IV */
1.102 djm 357: if (!EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_IV_GEN,
1.85 markus 358: 1, lastiv))
1.99 djm 359: return SSH_ERR_LIBCRYPTO_ERROR;
1.85 markus 360: /* set tag on decyption */
361: if (!cc->encrypt &&
1.102 djm 362: !EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_SET_TAG,
1.85 markus 363: authlen, (u_char *)src + aadlen + len))
1.99 djm 364: return SSH_ERR_LIBCRYPTO_ERROR;
1.85 markus 365: }
366: if (aadlen) {
367: if (authlen &&
1.102 djm 368: EVP_Cipher(cc->evp, NULL, (u_char *)src, aadlen) < 0)
1.99 djm 369: return SSH_ERR_LIBCRYPTO_ERROR;
1.83 markus 370: memcpy(dest, src, aadlen);
1.85 markus 371: }
1.32 markus 372: if (len % cc->cipher->block_size)
1.99 djm 373: return SSH_ERR_INVALID_ARGUMENT;
1.102 djm 374: if (EVP_Cipher(cc->evp, dest + aadlen, (u_char *)src + aadlen,
1.83 markus 375: len) < 0)
1.99 djm 376: return SSH_ERR_LIBCRYPTO_ERROR;
1.85 markus 377: if (authlen) {
378: /* compute tag (on encrypt) or verify tag (on decrypt) */
1.102 djm 379: if (EVP_Cipher(cc->evp, NULL, NULL, 0) < 0)
1.99 djm 380: return cc->encrypt ?
381: SSH_ERR_LIBCRYPTO_ERROR : SSH_ERR_MAC_INVALID;
1.85 markus 382: if (cc->encrypt &&
1.102 djm 383: !EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_GET_TAG,
1.85 markus 384: authlen, dest + aadlen + len))
1.99 djm 385: return SSH_ERR_LIBCRYPTO_ERROR;
1.85 markus 386: }
1.93 markus 387: return 0;
1.98 markus 388: #endif
1.21 markus 389: }
390:
1.91 djm 391: /* Extract the packet length, including any decryption necessary beforehand */
392: int
1.99 djm 393: cipher_get_length(struct sshcipher_ctx *cc, u_int *plenp, u_int seqnr,
1.91 djm 394: const u_char *cp, u_int len)
395: {
396: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
397: return chachapoly_get_length(&cc->cp_ctx, plenp, seqnr,
398: cp, len);
399: if (len < 4)
1.99 djm 400: return SSH_ERR_MESSAGE_INCOMPLETE;
1.111 markus 401: *plenp = PEEK_U32(cp);
1.91 djm 402: return 0;
403: }
404:
1.102 djm 405: void
406: cipher_free(struct sshcipher_ctx *cc)
1.16 markus 407: {
1.102 djm 408: if (cc == NULL)
409: return;
1.91 djm 410: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
1.96 djm 411: explicit_bzero(&cc->cp_ctx, sizeof(cc->cp_ctx));
1.98 markus 412: else if ((cc->cipher->flags & CFLAG_AESCTR) != 0)
413: explicit_bzero(&cc->ac_ctx, sizeof(cc->ac_ctx));
414: #ifdef WITH_OPENSSL
1.109 jsing 415: EVP_CIPHER_CTX_free(cc->evp);
416: cc->evp = NULL;
1.98 markus 417: #endif
1.102 djm 418: explicit_bzero(cc, sizeof(*cc));
419: free(cc);
1.52 markus 420: }
1.53 markus 421:
1.54 markus 422: /*
1.99 djm 423: * Exports an IV from the sshcipher_ctx required to export the key
1.53 markus 424: * state back from the unprivileged child to the privileged parent
425: * process.
426: */
427: int
1.99 djm 428: cipher_get_keyiv_len(const struct sshcipher_ctx *cc)
1.53 markus 429: {
1.99 djm 430: const struct sshcipher *c = cc->cipher;
1.53 markus 431:
1.104 djm 432: if ((c->flags & CFLAG_CHACHAPOLY) != 0)
433: return 0;
434: else if ((c->flags & CFLAG_AESCTR) != 0)
435: return sizeof(cc->ac_ctx.ctr);
1.98 markus 436: #ifdef WITH_OPENSSL
1.104 djm 437: return EVP_CIPHER_CTX_iv_length(cc->evp);
438: #else
439: return 0;
440: #endif
1.53 markus 441: }
442:
1.99 djm 443: int
1.112 djm 444: cipher_get_keyiv(struct sshcipher_ctx *cc, u_char *iv, size_t len)
1.53 markus 445: {
1.108 djm 446: #ifdef WITH_OPENSSL
1.99 djm 447: const struct sshcipher *c = cc->cipher;
1.110 djm 448: int evplen;
1.98 markus 449: #endif
1.53 markus 450:
1.91 djm 451: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
452: if (len != 0)
1.99 djm 453: return SSH_ERR_INVALID_ARGUMENT;
1.100 djm 454: return 0;
455: }
456: if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
457: if (len != sizeof(cc->ac_ctx.ctr))
458: return SSH_ERR_INVALID_ARGUMENT;
459: memcpy(iv, cc->ac_ctx.ctr, len);
1.99 djm 460: return 0;
1.91 djm 461: }
1.98 markus 462: if ((cc->cipher->flags & CFLAG_NONE) != 0)
1.99 djm 463: return 0;
1.91 djm 464:
1.98 markus 465: #ifdef WITH_OPENSSL
1.104 djm 466: evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
467: if (evplen == 0)
468: return 0;
469: else if (evplen < 0)
470: return SSH_ERR_LIBCRYPTO_ERROR;
1.112 djm 471: if ((size_t)evplen != len)
1.104 djm 472: return SSH_ERR_INVALID_ARGUMENT;
473: if (cipher_authlen(c)) {
474: if (!EVP_CIPHER_CTX_ctrl(cc->evp, EVP_CTRL_GCM_IV_GEN,
475: len, iv))
476: return SSH_ERR_LIBCRYPTO_ERROR;
1.112 djm 477: } else if (!EVP_CIPHER_CTX_get_iv(cc->evp, iv, len))
478: return SSH_ERR_LIBCRYPTO_ERROR;
1.98 markus 479: #endif
1.99 djm 480: return 0;
1.53 markus 481: }
482:
1.99 djm 483: int
1.112 djm 484: cipher_set_keyiv(struct sshcipher_ctx *cc, const u_char *iv, size_t len)
1.53 markus 485: {
1.108 djm 486: #ifdef WITH_OPENSSL
1.99 djm 487: const struct sshcipher *c = cc->cipher;
1.110 djm 488: int evplen = 0;
1.98 markus 489: #endif
1.91 djm 490:
491: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
1.99 djm 492: return 0;
1.98 markus 493: if ((cc->cipher->flags & CFLAG_NONE) != 0)
1.99 djm 494: return 0;
1.53 markus 495:
1.98 markus 496: #ifdef WITH_OPENSSL
1.104 djm 497: evplen = EVP_CIPHER_CTX_iv_length(cc->evp);
498: if (evplen <= 0)
499: return SSH_ERR_LIBCRYPTO_ERROR;
1.112 djm 500: if ((size_t)evplen != len)
501: return SSH_ERR_INVALID_ARGUMENT;
1.104 djm 502: if (cipher_authlen(c)) {
503: /* XXX iv arg is const, but EVP_CIPHER_CTX_ctrl isn't */
504: if (!EVP_CIPHER_CTX_ctrl(cc->evp,
505: EVP_CTRL_GCM_SET_IV_FIXED, -1, (void *)iv))
1.99 djm 506: return SSH_ERR_LIBCRYPTO_ERROR;
1.112 djm 507: } else if (!EVP_CIPHER_CTX_set_iv(cc->evp, iv, evplen))
508: return SSH_ERR_LIBCRYPTO_ERROR;
1.98 markus 509: #endif
1.99 djm 510: return 0;
1.53 markus 511: }
512:
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Return to cipher.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh