Annotation of src/usr.bin/ssh/cipher.c, Revision 1.98
1.98 ! markus 1: /* $OpenBSD: cipher.c,v 1.97 2014/02/07 06:55:54 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:
1.24 markus 44: #include "xmalloc.h"
1.42 markus 45: #include "log.h"
1.91 djm 46: #include "misc.h"
1.42 markus 47: #include "cipher.h"
1.95 markus 48: #include "buffer.h"
49: #include "digest.h"
1.57 markus 50:
1.98 ! markus 51: #ifdef WITH_SSH1
1.64 markus 52: extern const EVP_CIPHER *evp_ssh1_bf(void);
53: extern const EVP_CIPHER *evp_ssh1_3des(void);
54: extern void ssh1_3des_iv(EVP_CIPHER_CTX *, int, u_char *, int);
1.98 ! markus 55: #endif
1.1 deraadt 56:
1.51 markus 57: struct Cipher {
58: char *name;
59: int number; /* for ssh1 only */
60: u_int block_size;
61: u_int key_len;
1.85 markus 62: u_int iv_len; /* defaults to block_size */
63: u_int auth_len;
1.74 djm 64: u_int discard_len;
1.91 djm 65: u_int flags;
66: #define CFLAG_CBC (1<<0)
67: #define CFLAG_CHACHAPOLY (1<<1)
1.98 ! markus 68: #define CFLAG_AESCTR (1<<2)
! 69: #define CFLAG_NONE (1<<3)
! 70: #ifdef WITH_OPENSSL
1.56 markus 71: const EVP_CIPHER *(*evptype)(void);
1.98 ! markus 72: #else
! 73: void *ignored;
! 74: #endif
1.88 djm 75: };
76:
77: static const struct Cipher ciphers[] = {
1.98 ! markus 78: #ifdef WITH_SSH1
1.85 markus 79: { "des", SSH_CIPHER_DES, 8, 8, 0, 0, 0, 1, EVP_des_cbc },
80: { "3des", SSH_CIPHER_3DES, 8, 16, 0, 0, 0, 1, evp_ssh1_3des },
81: { "blowfish", SSH_CIPHER_BLOWFISH, 8, 32, 0, 0, 0, 1, evp_ssh1_bf },
1.98 ! markus 82: #endif
! 83: #ifdef WITH_OPENSSL
! 84: { "none", SSH_CIPHER_NONE, 8, 0, 0, 0, 0, 0, EVP_enc_null },
1.85 markus 85: { "3des-cbc", SSH_CIPHER_SSH2, 8, 24, 0, 0, 0, 1, EVP_des_ede3_cbc },
86: { "blowfish-cbc",
87: SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_bf_cbc },
88: { "cast128-cbc",
89: SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 1, EVP_cast5_cbc },
90: { "arcfour", SSH_CIPHER_SSH2, 8, 16, 0, 0, 0, 0, EVP_rc4 },
91: { "arcfour128", SSH_CIPHER_SSH2, 8, 16, 0, 0, 1536, 0, EVP_rc4 },
92: { "arcfour256", SSH_CIPHER_SSH2, 8, 32, 0, 0, 1536, 0, EVP_rc4 },
93: { "aes128-cbc", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 1, EVP_aes_128_cbc },
94: { "aes192-cbc", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 1, EVP_aes_192_cbc },
95: { "aes256-cbc", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
1.57 markus 96: { "rijndael-cbc@lysator.liu.se",
1.85 markus 97: SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 1, EVP_aes_256_cbc },
98: { "aes128-ctr", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, 0, EVP_aes_128_ctr },
99: { "aes192-ctr", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, 0, EVP_aes_192_ctr },
100: { "aes256-ctr", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, 0, EVP_aes_256_ctr },
101: { "aes128-gcm@openssh.com",
102: SSH_CIPHER_SSH2, 16, 16, 12, 16, 0, 0, EVP_aes_128_gcm },
103: { "aes256-gcm@openssh.com",
104: SSH_CIPHER_SSH2, 16, 32, 12, 16, 0, 0, EVP_aes_256_gcm },
1.98 ! markus 105: #else
! 106: { "aes128-ctr", SSH_CIPHER_SSH2, 16, 16, 0, 0, 0, CFLAG_AESCTR, NULL },
! 107: { "aes192-ctr", SSH_CIPHER_SSH2, 16, 24, 0, 0, 0, CFLAG_AESCTR, NULL },
! 108: { "aes256-ctr", SSH_CIPHER_SSH2, 16, 32, 0, 0, 0, CFLAG_AESCTR, NULL },
! 109: { "none", SSH_CIPHER_NONE, 8, 0, 0, 0, 0, CFLAG_NONE, NULL },
! 110: #endif
1.91 djm 111: { "chacha20-poly1305@openssh.com",
112: SSH_CIPHER_SSH2, 8, 64, 0, 16, 0, CFLAG_CHACHAPOLY, NULL },
1.47 markus 113:
1.85 markus 114: { NULL, SSH_CIPHER_INVALID, 0, 0, 0, 0, 0, 0, NULL }
1.32 markus 115: };
116:
117: /*--*/
1.1 deraadt 118:
1.90 dtucker 119: /* Returns a list of supported ciphers separated by the specified char. */
1.88 djm 120: char *
1.91 djm 121: cipher_alg_list(char sep, int auth_only)
1.88 djm 122: {
123: char *ret = NULL;
124: size_t nlen, rlen = 0;
125: const Cipher *c;
126:
127: for (c = ciphers; c->name != NULL; c++) {
128: if (c->number != SSH_CIPHER_SSH2)
129: continue;
1.91 djm 130: if (auth_only && c->auth_len == 0)
131: continue;
1.88 djm 132: if (ret != NULL)
1.90 dtucker 133: ret[rlen++] = sep;
1.88 djm 134: nlen = strlen(c->name);
135: ret = xrealloc(ret, 1, rlen + nlen + 2);
136: memcpy(ret + rlen, c->name, nlen + 1);
137: rlen += nlen;
138: }
139: return ret;
140: }
141:
1.54 markus 142: u_int
1.66 jakob 143: cipher_blocksize(const Cipher *c)
1.51 markus 144: {
145: return (c->block_size);
146: }
1.60 deraadt 147:
1.54 markus 148: u_int
1.66 jakob 149: cipher_keylen(const Cipher *c)
1.51 markus 150: {
151: return (c->key_len);
1.94 dtucker 152: }
153:
154: u_int
155: cipher_seclen(const Cipher *c)
156: {
157: if (strcmp("3des-cbc", c->name) == 0)
158: return 14;
159: return cipher_keylen(c);
1.51 markus 160: }
1.60 deraadt 161:
1.54 markus 162: u_int
1.85 markus 163: cipher_authlen(const Cipher *c)
164: {
165: return (c->auth_len);
166: }
167:
168: u_int
169: cipher_ivlen(const Cipher *c)
170: {
1.91 djm 171: /*
172: * Default is cipher block size, except for chacha20+poly1305 that
173: * needs no IV. XXX make iv_len == -1 default?
174: */
175: return (c->iv_len != 0 || (c->flags & CFLAG_CHACHAPOLY) != 0) ?
176: c->iv_len : c->block_size;
1.85 markus 177: }
178:
179: u_int
1.66 jakob 180: cipher_get_number(const Cipher *c)
1.53 markus 181: {
182: return (c->number);
1.82 markus 183: }
184:
185: u_int
186: cipher_is_cbc(const Cipher *c)
187: {
1.91 djm 188: return (c->flags & CFLAG_CBC) != 0;
1.53 markus 189: }
1.51 markus 190:
1.41 markus 191: u_int
1.34 markus 192: cipher_mask_ssh1(int client)
1.1 deraadt 193: {
1.41 markus 194: u_int mask = 0;
1.48 deraadt 195: mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
1.34 markus 196: mask |= 1 << SSH_CIPHER_BLOWFISH;
197: if (client) {
198: mask |= 1 << SSH_CIPHER_DES;
1.32 markus 199: }
200: return mask;
1.1 deraadt 201: }
202:
1.88 djm 203: const Cipher *
1.32 markus 204: cipher_by_name(const char *name)
205: {
1.88 djm 206: const Cipher *c;
1.32 markus 207: for (c = ciphers; c->name != NULL; c++)
1.73 djm 208: if (strcmp(c->name, name) == 0)
1.32 markus 209: return c;
210: return NULL;
211: }
212:
1.88 djm 213: const Cipher *
1.32 markus 214: cipher_by_number(int id)
215: {
1.88 djm 216: const Cipher *c;
1.32 markus 217: for (c = ciphers; c->name != NULL; c++)
218: if (c->number == id)
219: return c;
220: return NULL;
221: }
1.24 markus 222:
223: #define CIPHER_SEP ","
224: int
225: ciphers_valid(const char *names)
226: {
1.88 djm 227: const Cipher *c;
1.69 avsm 228: char *cipher_list, *cp;
1.24 markus 229: char *p;
230:
1.27 markus 231: if (names == NULL || strcmp(names, "") == 0)
1.24 markus 232: return 0;
1.69 avsm 233: cipher_list = cp = xstrdup(names);
1.32 markus 234: for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
1.48 deraadt 235: (p = strsep(&cp, CIPHER_SEP))) {
1.32 markus 236: c = cipher_by_name(p);
237: if (c == NULL || c->number != SSH_CIPHER_SSH2) {
238: debug("bad cipher %s [%s]", p, names);
1.89 djm 239: free(cipher_list);
1.24 markus 240: return 0;
241: }
242: }
1.36 markus 243: debug3("ciphers ok: [%s]", names);
1.89 djm 244: free(cipher_list);
1.24 markus 245: return 1;
246: }
247:
1.18 markus 248: /*
249: * Parses the name of the cipher. Returns the number of the corresponding
250: * cipher, or -1 on error.
251: */
1.1 deraadt 252:
1.4 provos 253: int
254: cipher_number(const char *name)
1.1 deraadt 255: {
1.88 djm 256: const Cipher *c;
1.27 markus 257: if (name == NULL)
258: return -1;
1.73 djm 259: for (c = ciphers; c->name != NULL; c++)
260: if (strcasecmp(c->name, name) == 0)
261: return c->number;
262: return -1;
1.1 deraadt 263: }
264:
1.32 markus 265: char *
266: cipher_name(int id)
1.1 deraadt 267: {
1.88 djm 268: const Cipher *c = cipher_by_number(id);
1.32 markus 269: return (c==NULL) ? "<unknown>" : c->name;
1.1 deraadt 270: }
271:
1.26 markus 272: void
1.88 djm 273: cipher_init(CipherContext *cc, const Cipher *cipher,
1.52 markus 274: const u_char *key, u_int keylen, const u_char *iv, u_int ivlen,
1.69 avsm 275: int do_encrypt)
1.16 markus 276: {
1.98 ! markus 277: #ifdef WITH_OPENSSL
1.52 markus 278: static int dowarn = 1;
279: const EVP_CIPHER *type;
280: int klen;
1.74 djm 281: u_char *junk, *discard;
1.52 markus 282:
283: if (cipher->number == SSH_CIPHER_DES) {
284: if (dowarn) {
285: error("Warning: use of DES is strongly discouraged "
286: "due to cryptographic weaknesses");
287: dowarn = 0;
288: }
289: if (keylen > 8)
290: keylen = 8;
291: }
1.98 ! markus 292: #endif
1.52 markus 293: cc->plaintext = (cipher->number == SSH_CIPHER_NONE);
1.85 markus 294: cc->encrypt = do_encrypt;
1.52 markus 295:
1.32 markus 296: if (keylen < cipher->key_len)
297: fatal("cipher_init: key length %d is insufficient for %s.",
298: keylen, cipher->name);
1.85 markus 299: if (iv != NULL && ivlen < cipher_ivlen(cipher))
1.32 markus 300: fatal("cipher_init: iv length %d is insufficient for %s.",
301: ivlen, cipher->name);
302: cc->cipher = cipher;
1.52 markus 303:
1.91 djm 304: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
305: chachapoly_init(&cc->cp_ctx, key, keylen);
306: return;
307: }
1.98 ! markus 308: #ifndef WITH_OPENSSL
! 309: if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
! 310: aesctr_keysetup(&cc->ac_ctx, key, 8 * keylen, 8 * ivlen);
! 311: aesctr_ivsetup(&cc->ac_ctx, iv);
! 312: return;
! 313: }
! 314: if ((cc->cipher->flags & CFLAG_NONE) != 0)
! 315: return;
! 316: fatal("unsupported cipher");
! 317: #else
1.52 markus 318: type = (*cipher->evptype)();
319: EVP_CIPHER_CTX_init(&cc->evp);
320: if (EVP_CipherInit(&cc->evp, type, NULL, (u_char *)iv,
1.69 avsm 321: (do_encrypt == CIPHER_ENCRYPT)) == 0)
1.52 markus 322: fatal("cipher_init: EVP_CipherInit failed for %s",
323: cipher->name);
1.85 markus 324: if (cipher_authlen(cipher) &&
325: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_SET_IV_FIXED,
326: -1, (u_char *)iv))
327: fatal("cipher_init: EVP_CTRL_GCM_SET_IV_FIXED failed for %s",
328: cipher->name);
1.52 markus 329: klen = EVP_CIPHER_CTX_key_length(&cc->evp);
1.76 djm 330: if (klen > 0 && keylen != (u_int)klen) {
1.62 markus 331: debug2("cipher_init: set keylen (%d -> %d)", klen, keylen);
1.52 markus 332: if (EVP_CIPHER_CTX_set_key_length(&cc->evp, keylen) == 0)
333: fatal("cipher_init: set keylen failed (%d -> %d)",
334: klen, keylen);
335: }
336: if (EVP_CipherInit(&cc->evp, NULL, (u_char *)key, NULL, -1) == 0)
337: fatal("cipher_init: EVP_CipherInit: set key failed for %s",
338: cipher->name);
1.74 djm 339:
1.77 djm 340: if (cipher->discard_len > 0) {
1.74 djm 341: junk = xmalloc(cipher->discard_len);
342: discard = xmalloc(cipher->discard_len);
343: if (EVP_Cipher(&cc->evp, discard, junk,
344: cipher->discard_len) == 0)
345: fatal("evp_crypt: EVP_Cipher failed during discard");
1.96 djm 346: explicit_bzero(discard, cipher->discard_len);
1.89 djm 347: free(junk);
348: free(discard);
1.74 djm 349: }
1.98 ! markus 350: #endif
1.1 deraadt 351: }
1.21 markus 352:
1.83 markus 353: /*
354: * cipher_crypt() operates as following:
355: * Copy 'aadlen' bytes (without en/decryption) from 'src' to 'dest'.
356: * Theses bytes are treated as additional authenticated data for
357: * authenticated encryption modes.
358: * En/Decrypt 'len' bytes at offset 'aadlen' from 'src' to 'dest'.
1.85 markus 359: * Use 'authlen' bytes at offset 'len'+'aadlen' as the authentication tag.
360: * This tag is written on encryption and verified on decryption.
1.83 markus 361: * Both 'aadlen' and 'authlen' can be set to 0.
1.93 markus 362: * cipher_crypt() returns 0 on success and -1 if the decryption integrity
363: * check fails.
1.83 markus 364: */
1.93 markus 365: int
1.91 djm 366: cipher_crypt(CipherContext *cc, u_int seqnr, u_char *dest, const u_char *src,
1.85 markus 367: u_int len, u_int aadlen, u_int authlen)
1.32 markus 368: {
1.93 markus 369: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
370: return chachapoly_crypt(&cc->cp_ctx, seqnr, dest, src, len,
371: aadlen, authlen, cc->encrypt);
1.98 ! markus 372: #ifndef WITH_OPENSSL
! 373: if ((cc->cipher->flags & CFLAG_AESCTR) != 0) {
! 374: if (aadlen)
! 375: memcpy(dest, src, aadlen);
! 376: aesctr_encrypt_bytes(&cc->ac_ctx, src + aadlen,
! 377: dest + aadlen, len);
! 378: return 0;
! 379: }
! 380: if ((cc->cipher->flags & CFLAG_NONE) != 0) {
! 381: memcpy(dest, src, aadlen + len);
! 382: return 0;
! 383: }
! 384: fatal("unsupported cipher");
! 385: #else
1.85 markus 386: if (authlen) {
387: u_char lastiv[1];
388:
389: if (authlen != cipher_authlen(cc->cipher))
390: fatal("%s: authlen mismatch %d", __func__, authlen);
391: /* increment IV */
392: if (!EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_IV_GEN,
393: 1, lastiv))
394: fatal("%s: EVP_CTRL_GCM_IV_GEN", __func__);
395: /* set tag on decyption */
396: if (!cc->encrypt &&
397: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_SET_TAG,
398: authlen, (u_char *)src + aadlen + len))
399: fatal("%s: EVP_CTRL_GCM_SET_TAG", __func__);
400: }
401: if (aadlen) {
402: if (authlen &&
403: EVP_Cipher(&cc->evp, NULL, (u_char *)src, aadlen) < 0)
404: fatal("%s: EVP_Cipher(aad) failed", __func__);
1.83 markus 405: memcpy(dest, src, aadlen);
1.85 markus 406: }
1.32 markus 407: if (len % cc->cipher->block_size)
1.83 markus 408: fatal("%s: bad plaintext length %d", __func__, len);
409: if (EVP_Cipher(&cc->evp, dest + aadlen, (u_char *)src + aadlen,
410: len) < 0)
411: fatal("%s: EVP_Cipher failed", __func__);
1.85 markus 412: if (authlen) {
413: /* compute tag (on encrypt) or verify tag (on decrypt) */
1.86 djm 414: if (EVP_Cipher(&cc->evp, NULL, NULL, 0) < 0) {
415: if (cc->encrypt)
416: fatal("%s: EVP_Cipher(final) failed", __func__);
417: else
1.93 markus 418: return -1;
1.86 djm 419: }
1.85 markus 420: if (cc->encrypt &&
421: !EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_GET_TAG,
422: authlen, dest + aadlen + len))
423: fatal("%s: EVP_CTRL_GCM_GET_TAG", __func__);
424: }
1.93 markus 425: return 0;
1.98 ! markus 426: #endif
1.21 markus 427: }
428:
1.91 djm 429: /* Extract the packet length, including any decryption necessary beforehand */
430: int
431: cipher_get_length(CipherContext *cc, u_int *plenp, u_int seqnr,
432: const u_char *cp, u_int len)
433: {
434: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
435: return chachapoly_get_length(&cc->cp_ctx, plenp, seqnr,
436: cp, len);
437: if (len < 4)
438: return -1;
439: *plenp = get_u32(cp);
440: return 0;
441: }
442:
1.26 markus 443: void
1.51 markus 444: cipher_cleanup(CipherContext *cc)
1.16 markus 445: {
1.91 djm 446: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
1.96 djm 447: explicit_bzero(&cc->cp_ctx, sizeof(cc->cp_ctx));
1.98 ! markus 448: else if ((cc->cipher->flags & CFLAG_AESCTR) != 0)
! 449: explicit_bzero(&cc->ac_ctx, sizeof(cc->ac_ctx));
! 450: #ifdef WITH_OPENSSL
1.91 djm 451: else if (EVP_CIPHER_CTX_cleanup(&cc->evp) == 0)
1.52 markus 452: error("cipher_cleanup: EVP_CIPHER_CTX_cleanup failed");
1.98 ! markus 453: #endif
1.16 markus 454: }
1.1 deraadt 455:
1.32 markus 456: /*
457: * Selects the cipher, and keys if by computing the MD5 checksum of the
458: * passphrase and using the resulting 16 bytes as the key.
459: */
1.1 deraadt 460:
1.26 markus 461: void
1.88 djm 462: cipher_set_key_string(CipherContext *cc, const Cipher *cipher,
1.69 avsm 463: const char *passphrase, int do_encrypt)
1.16 markus 464: {
1.41 markus 465: u_char digest[16];
1.32 markus 466:
1.95 markus 467: if (ssh_digest_memory(SSH_DIGEST_MD5, passphrase, strlen(passphrase),
468: digest, sizeof(digest)) < 0)
469: fatal("%s: md5 failed", __func__);
1.16 markus 470:
1.69 avsm 471: cipher_init(cc, cipher, digest, 16, NULL, 0, do_encrypt);
1.16 markus 472:
1.96 djm 473: explicit_bzero(digest, sizeof(digest));
1.52 markus 474: }
1.53 markus 475:
1.54 markus 476: /*
1.53 markus 477: * Exports an IV from the CipherContext required to export the key
478: * state back from the unprivileged child to the privileged parent
479: * process.
480: */
481:
482: int
1.66 jakob 483: cipher_get_keyiv_len(const CipherContext *cc)
1.53 markus 484: {
1.88 djm 485: const Cipher *c = cc->cipher;
1.98 ! markus 486: int ivlen = 0;
1.53 markus 487:
488: if (c->number == SSH_CIPHER_3DES)
489: ivlen = 24;
1.91 djm 490: else if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
491: ivlen = 0;
1.98 ! markus 492: #ifdef WITH_OPENSSL
1.53 markus 493: else
494: ivlen = EVP_CIPHER_CTX_iv_length(&cc->evp);
1.98 ! markus 495: #endif
1.53 markus 496: return (ivlen);
497: }
498:
499: void
500: cipher_get_keyiv(CipherContext *cc, u_char *iv, u_int len)
501: {
1.88 djm 502: const Cipher *c = cc->cipher;
1.98 ! markus 503: #ifdef WITH_OPENSSL
1.53 markus 504: int evplen;
1.98 ! markus 505: #endif
1.53 markus 506:
1.91 djm 507: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0) {
508: if (len != 0)
509: fatal("%s: wrong iv length %d != %d", __func__, len, 0);
510: return;
511: }
1.98 ! markus 512: if ((cc->cipher->flags & CFLAG_NONE) != 0)
! 513: return;
1.91 djm 514:
1.53 markus 515: switch (c->number) {
1.98 ! markus 516: #ifdef WITH_OPENSSL
1.53 markus 517: case SSH_CIPHER_SSH2:
518: case SSH_CIPHER_DES:
519: case SSH_CIPHER_BLOWFISH:
520: evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
1.76 djm 521: if (evplen <= 0)
1.53 markus 522: return;
1.76 djm 523: if ((u_int)evplen != len)
1.58 markus 524: fatal("%s: wrong iv length %d != %d", __func__,
1.53 markus 525: evplen, len);
1.85 markus 526: if (cipher_authlen(c)) {
527: if (!EVP_CIPHER_CTX_ctrl(&cc->evp, EVP_CTRL_GCM_IV_GEN,
528: len, iv))
529: fatal("%s: EVP_CTRL_GCM_IV_GEN", __func__);
530: } else
531: memcpy(iv, cc->evp.iv, len);
1.63 markus 532: break;
1.98 ! markus 533: #endif
! 534: #ifdef WITH_SSH1
1.63 markus 535: case SSH_CIPHER_3DES:
536: ssh1_3des_iv(&cc->evp, 0, iv, 24);
1.53 markus 537: break;
1.98 ! markus 538: #endif
1.53 markus 539: default:
1.58 markus 540: fatal("%s: bad cipher %d", __func__, c->number);
1.53 markus 541: }
542: }
543:
544: void
545: cipher_set_keyiv(CipherContext *cc, u_char *iv)
546: {
1.88 djm 547: const Cipher *c = cc->cipher;
1.98 ! markus 548: #ifdef WITH_OPENSSL
1.53 markus 549: int evplen = 0;
1.98 ! markus 550: #endif
1.91 djm 551:
552: if ((cc->cipher->flags & CFLAG_CHACHAPOLY) != 0)
553: return;
1.98 ! markus 554: if ((cc->cipher->flags & CFLAG_NONE) != 0)
! 555: return;
1.53 markus 556:
557: switch (c->number) {
1.98 ! markus 558: #ifdef WITH_OPENSSL
1.53 markus 559: case SSH_CIPHER_SSH2:
560: case SSH_CIPHER_DES:
561: case SSH_CIPHER_BLOWFISH:
562: evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
563: if (evplen == 0)
564: return;
1.85 markus 565: if (cipher_authlen(c)) {
566: if (!EVP_CIPHER_CTX_ctrl(&cc->evp,
567: EVP_CTRL_GCM_SET_IV_FIXED, -1, iv))
568: fatal("%s: EVP_CTRL_GCM_SET_IV_FIXED failed",
569: __func__);
570: } else
571: memcpy(cc->evp.iv, iv, evplen);
1.63 markus 572: break;
1.98 ! markus 573: #endif
! 574: #ifdef WITH_SSH1
1.63 markus 575: case SSH_CIPHER_3DES:
576: ssh1_3des_iv(&cc->evp, 1, iv, 24);
1.53 markus 577: break;
1.98 ! markus 578: #endif
1.53 markus 579: default:
1.58 markus 580: fatal("%s: bad cipher %d", __func__, c->number);
1.53 markus 581: }
582: }
583:
1.98 ! markus 584: #ifdef WITH_OPENSSL
1.53 markus 585: #define EVP_X_STATE(evp) (evp).cipher_data
586: #define EVP_X_STATE_LEN(evp) (evp).cipher->ctx_size
1.98 ! markus 587: #endif
1.53 markus 588:
589: int
1.66 jakob 590: cipher_get_keycontext(const CipherContext *cc, u_char *dat)
1.53 markus 591: {
1.98 ! markus 592: #ifdef WITH_OPENSSL
1.88 djm 593: const Cipher *c = cc->cipher;
1.59 markus 594: int plen = 0;
1.53 markus 595:
1.87 djm 596: if (c->evptype == EVP_rc4) {
1.59 markus 597: plen = EVP_X_STATE_LEN(cc->evp);
1.53 markus 598: if (dat == NULL)
1.59 markus 599: return (plen);
600: memcpy(dat, EVP_X_STATE(cc->evp), plen);
1.53 markus 601: }
602: return (plen);
1.98 ! markus 603: #else
! 604: return (0);
! 605: #endif
1.53 markus 606: }
607:
608: void
609: cipher_set_keycontext(CipherContext *cc, u_char *dat)
610: {
1.98 ! markus 611: #ifdef WITH_OPENSSL
1.88 djm 612: const Cipher *c = cc->cipher;
1.53 markus 613: int plen;
614:
1.87 djm 615: if (c->evptype == EVP_rc4) {
1.53 markus 616: plen = EVP_X_STATE_LEN(cc->evp);
617: memcpy(EVP_X_STATE(cc->evp), dat, plen);
618: }
1.98 ! markus 619: #endif
1.1 deraadt 620: }
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