Annotation of src/usr.bin/ssh/cipher.c, Revision 1.37.2.2
1.1 deraadt 1: /*
1.30 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
1.26 markus 5: *
1.30 deraadt 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".
1.26 markus 11: *
12: *
1.30 deraadt 13: * Copyright (c) 1999 Niels Provos. All rights reserved.
14: * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
1.26 markus 15: *
1.30 deraadt 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.
1.26 markus 24: *
1.30 deraadt 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.
1.17 deraadt 35: */
1.1 deraadt 36:
37: #include "includes.h"
1.37.2.1 jason 38: RCSID("$OpenBSD: cipher.c,v 1.43 2001/02/04 15:32:23 stevesk Exp $");
1.1 deraadt 39:
1.24 markus 40: #include "xmalloc.h"
1.37.2.1 jason 41: #include "log.h"
42: #include "cipher.h"
1.8 deraadt 43:
1.25 markus 44: #include <openssl/md5.h>
1.1 deraadt 45:
1.32 markus 46:
47: /* no encryption */
48: void
49: none_setkey(CipherContext *cc, const u_char *key, u_int keylen)
50: {
51: }
52: void
53: none_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
54: {
55: }
56: void
57: none_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
58: {
59: memcpy(dest, src, len);
60: }
61:
62: /* DES */
63: void
64: des_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
65: {
1.34 markus 66: static int dowarn = 1;
67: if (dowarn) {
68: error("Warning: use of DES is strongly discouraged "
69: "due to cryptographic weaknesses");
70: dowarn = 0;
71: }
1.32 markus 72: des_set_key((void *)key, cc->u.des.key);
73: }
74: void
75: des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
76: {
77: memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv));
78: }
79: void
80: des_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
81: {
82: des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
83: DES_ENCRYPT);
84: }
85: void
86: des_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
87: {
88: des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
89: DES_DECRYPT);
90: }
91:
92: /* 3DES */
93: void
94: des3_setkey(CipherContext *cc, const u_char *key, u_int keylen)
95: {
96: des_set_key((void *) key, cc->u.des3.key1);
97: des_set_key((void *) (key+8), cc->u.des3.key2);
98: des_set_key((void *) (key+16), cc->u.des3.key3);
99: }
100: void
101: des3_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
102: {
103: memset(cc->u.des3.iv2, 0, sizeof(cc->u.des3.iv2));
104: memset(cc->u.des3.iv3, 0, sizeof(cc->u.des3.iv3));
105: if (iv == NULL)
106: return;
107: memcpy(cc->u.des3.iv3, (char *)iv, 8);
108: }
109: void
110: des3_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
111: {
112: des_ede3_cbc_encrypt(src, dest, len,
113: cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
114: &cc->u.des3.iv3, DES_ENCRYPT);
115: }
116: void
117: des3_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
118: {
119: des_ede3_cbc_encrypt(src, dest, len,
120: cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
121: &cc->u.des3.iv3, DES_DECRYPT);
122: }
123:
1.1 deraadt 124: /*
1.24 markus 125: * This is used by SSH1:
126: *
1.23 deraadt 127: * What kind of triple DES are these 2 routines?
1.1 deraadt 128: *
129: * Why is there a redundant initialization vector?
130: *
131: * If only iv3 was used, then, this would till effect have been
132: * outer-cbc. However, there is also a private iv1 == iv2 which
133: * perhaps makes differential analysis easier. On the other hand, the
134: * private iv1 probably makes the CRC-32 attack ineffective. This is a
135: * result of that there is no longer any known iv1 to use when
136: * choosing the X block.
137: */
138: void
1.32 markus 139: des3_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
140: {
141: des_set_key((void *) key, cc->u.des3.key1);
142: des_set_key((void *) (key+8), cc->u.des3.key2);
143: if (keylen <= 16)
144: des_set_key((void *) key, cc->u.des3.key3);
145: else
146: des_set_key((void *) (key+16), cc->u.des3.key3);
147: }
148: void
149: des3_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
150: u_int len)
1.1 deraadt 151: {
1.16 markus 152: des_cblock iv1;
1.32 markus 153: des_cblock *iv2 = &cc->u.des3.iv2;
154: des_cblock *iv3 = &cc->u.des3.iv3;
1.1 deraadt 155:
1.16 markus 156: memcpy(&iv1, iv2, 8);
1.1 deraadt 157:
1.37.2.1 jason 158: des_ncbc_encrypt(src, dest, len, cc->u.des3.key1, &iv1, DES_ENCRYPT);
159: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_DECRYPT);
160: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key3, iv3, DES_ENCRYPT);
1.1 deraadt 161: }
162: void
1.32 markus 163: des3_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
164: u_int len)
1.1 deraadt 165: {
1.16 markus 166: des_cblock iv1;
1.32 markus 167: des_cblock *iv2 = &cc->u.des3.iv2;
168: des_cblock *iv3 = &cc->u.des3.iv3;
1.1 deraadt 169:
1.16 markus 170: memcpy(&iv1, iv2, 8);
1.1 deraadt 171:
1.37.2.1 jason 172: des_ncbc_encrypt(src, dest, len, cc->u.des3.key3, iv3, DES_DECRYPT);
173: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_ENCRYPT);
174: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key1, &iv1, DES_DECRYPT);
1.1 deraadt 175: }
176:
1.32 markus 177: /* Blowfish */
178: void
179: blowfish_setkey(CipherContext *cc, const u_char *key, u_int keylen)
180: {
1.37.2.1 jason 181: BF_set_key(&cc->u.bf.key, keylen, (u_char *)key);
1.32 markus 182: }
183: void
184: blowfish_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
185: {
186: if (iv == NULL)
187: memset(cc->u.bf.iv, 0, 8);
188: else
189: memcpy(cc->u.bf.iv, (char *)iv, 8);
190: }
191: void
192: blowfish_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
193: u_int len)
194: {
195: BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
196: BF_ENCRYPT);
197: }
198: void
199: blowfish_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
200: u_int len)
201: {
202: BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
203: BF_DECRYPT);
204: }
205:
1.1 deraadt 206: /*
1.24 markus 207: * SSH1 uses a variation on Blowfish, all bytes must be swapped before
1.1 deraadt 208: * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
209: */
1.16 markus 210: static void
1.37.2.1 jason 211: swap_bytes(const u_char *src, u_char *dst, int n)
1.1 deraadt 212: {
1.37 markus 213: char c[4];
214:
215: /* Process 4 bytes every lap. */
216: for (n = n / 4; n > 0; n--) {
217: c[3] = *src++;
218: c[2] = *src++;
219: c[1] = *src++;
220: c[0] = *src++;
221:
222: *dst++ = c[0];
223: *dst++ = c[1];
224: *dst++ = c[2];
225: *dst++ = c[3];
1.16 markus 226: }
1.1 deraadt 227: }
228:
1.32 markus 229: void
230: blowfish_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
231: u_int len)
232: {
233: swap_bytes(src, dest, len);
234: BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
235: BF_ENCRYPT);
236: swap_bytes(dest, dest, len);
237: }
238: void
239: blowfish_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
240: u_int len)
1.4 provos 241: {
1.32 markus 242: swap_bytes(src, dest, len);
243: BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
244: BF_DECRYPT);
245: swap_bytes(dest, dest, len);
246: }
1.1 deraadt 247:
1.32 markus 248: /* alleged rc4 */
249: void
250: arcfour_setkey(CipherContext *cc, const u_char *key, u_int keylen)
251: {
252: RC4_set_key(&cc->u.rc4, keylen, (u_char *)key);
253: }
254: void
255: arcfour_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
256: {
257: RC4(&cc->u.rc4, len, (u_char *)src, dest);
258: }
1.1 deraadt 259:
1.32 markus 260: /* CAST */
261: void
262: cast_setkey(CipherContext *cc, const u_char *key, u_int keylen)
263: {
1.37.2.1 jason 264: CAST_set_key(&cc->u.cast.key, keylen, (u_char *) key);
1.32 markus 265: }
266: void
267: cast_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
1.1 deraadt 268: {
1.37.2.1 jason 269: if (iv == NULL)
1.32 markus 270: fatal("no IV for %s.", cc->cipher->name);
271: memcpy(cc->u.cast.iv, (char *)iv, 8);
1.22 markus 272: }
1.32 markus 273: void
274: cast_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.22 markus 275: {
1.32 markus 276: CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
277: CAST_ENCRYPT);
1.1 deraadt 278: }
1.32 markus 279: void
280: cast_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.22 markus 281: {
1.32 markus 282: CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
283: CAST_DECRYPT);
1.22 markus 284: }
1.1 deraadt 285:
1.35 markus 286: /* RIJNDAEL */
287:
288: #define RIJNDAEL_BLOCKSIZE 16
289: void
290: rijndael_setkey(CipherContext *cc, const u_char *key, u_int keylen)
291: {
292: rijndael_set_key(&cc->u.rijndael.enc, (u4byte *)key, 8*keylen, 1);
293: rijndael_set_key(&cc->u.rijndael.dec, (u4byte *)key, 8*keylen, 0);
294: }
295: void
296: rijndael_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
297: {
1.37.2.1 jason 298: if (iv == NULL)
1.35 markus 299: fatal("no IV for %s.", cc->cipher->name);
300: memcpy((u_char *)cc->u.rijndael.iv, iv, RIJNDAEL_BLOCKSIZE);
301: }
302: void
303: rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
304: u_int len)
305: {
306: rijndael_ctx *ctx = &cc->u.rijndael.enc;
307: u4byte *iv = cc->u.rijndael.iv;
308: u4byte in[4];
309: u4byte *cprev, *cnow, *plain;
310: int i, blocks = len / RIJNDAEL_BLOCKSIZE;
311: if (len == 0)
312: return;
313: if (len % RIJNDAEL_BLOCKSIZE)
314: fatal("rijndael_cbc_encrypt: bad len %d", len);
315: cnow = (u4byte*) dest;
316: plain = (u4byte*) src;
317: cprev = iv;
318: for(i = 0; i < blocks; i++, plain+=4, cnow+=4) {
319: in[0] = plain[0] ^ cprev[0];
320: in[1] = plain[1] ^ cprev[1];
321: in[2] = plain[2] ^ cprev[2];
322: in[3] = plain[3] ^ cprev[3];
323: rijndael_encrypt(ctx, in, cnow);
324: cprev = cnow;
325: }
326: memcpy(iv, cprev, RIJNDAEL_BLOCKSIZE);
327: }
328:
329: void
330: rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
331: u_int len)
332: {
333: rijndael_ctx *ctx = &cc->u.rijndael.dec;
334: u4byte *iv = cc->u.rijndael.iv;
335: u4byte ivsaved[4];
336: u4byte *cnow = (u4byte*) (src+len-RIJNDAEL_BLOCKSIZE);
337: u4byte *plain = (u4byte*) (dest+len-RIJNDAEL_BLOCKSIZE);
338: u4byte *ivp;
339: int i, blocks = len / RIJNDAEL_BLOCKSIZE;
340: if (len == 0)
341: return;
342: if (len % RIJNDAEL_BLOCKSIZE)
343: fatal("rijndael_cbc_decrypt: bad len %d", len);
344: memcpy(ivsaved, cnow, RIJNDAEL_BLOCKSIZE);
345: for(i = blocks; i > 0; i--, cnow-=4, plain-=4) {
346: rijndael_decrypt(ctx, cnow, plain);
347: ivp = (i == 1) ? iv : cnow-4;
348: plain[0] ^= ivp[0];
349: plain[1] ^= ivp[1];
350: plain[2] ^= ivp[2];
351: plain[3] ^= ivp[3];
352: }
353: memcpy(iv, ivsaved, RIJNDAEL_BLOCKSIZE);
354: }
1.32 markus 355:
356: Cipher ciphers[] = {
357: { "none",
358: SSH_CIPHER_NONE, 8, 0,
359: none_setkey, none_setiv,
360: none_crypt, none_crypt },
1.34 markus 361: { "des",
362: SSH_CIPHER_DES, 8, 8,
363: des_ssh1_setkey, des_ssh1_setiv,
364: des_ssh1_encrypt, des_ssh1_decrypt },
1.32 markus 365: { "3des",
366: SSH_CIPHER_3DES, 8, 16,
367: des3_ssh1_setkey, des3_setiv,
368: des3_ssh1_encrypt, des3_ssh1_decrypt },
369: { "blowfish",
370: SSH_CIPHER_BLOWFISH, 8, 16,
371: blowfish_setkey, blowfish_setiv,
372: blowfish_ssh1_encrypt, blowfish_ssh1_decrypt },
373:
374: { "3des-cbc",
375: SSH_CIPHER_SSH2, 8, 24,
376: des3_setkey, des3_setiv,
377: des3_cbc_encrypt, des3_cbc_decrypt },
378: { "blowfish-cbc",
379: SSH_CIPHER_SSH2, 8, 16,
380: blowfish_setkey, blowfish_setiv,
381: blowfish_cbc_encrypt, blowfish_cbc_decrypt },
382: { "cast128-cbc",
383: SSH_CIPHER_SSH2, 8, 16,
384: cast_setkey, cast_setiv,
385: cast_cbc_encrypt, cast_cbc_decrypt },
386: { "arcfour",
387: SSH_CIPHER_SSH2, 8, 16,
388: arcfour_setkey, none_setiv,
389: arcfour_crypt, arcfour_crypt },
1.35 markus 390: { "aes128-cbc",
391: SSH_CIPHER_SSH2, 16, 16,
392: rijndael_setkey, rijndael_setiv,
393: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
394: { "aes192-cbc",
395: SSH_CIPHER_SSH2, 16, 24,
396: rijndael_setkey, rijndael_setiv,
397: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
398: { "aes256-cbc",
399: SSH_CIPHER_SSH2, 16, 32,
400: rijndael_setkey, rijndael_setiv,
401: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
402: { "rijndael128-cbc",
403: SSH_CIPHER_SSH2, 16, 16,
404: rijndael_setkey, rijndael_setiv,
405: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
406: { "rijndael192-cbc",
407: SSH_CIPHER_SSH2, 16, 24,
408: rijndael_setkey, rijndael_setiv,
409: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
410: { "rijndael256-cbc",
411: SSH_CIPHER_SSH2, 16, 32,
412: rijndael_setkey, rijndael_setiv,
413: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
414: { "rijndael-cbc@lysator.liu.se",
415: SSH_CIPHER_SSH2, 16, 32,
416: rijndael_setkey, rijndael_setiv,
417: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
1.37.2.1 jason 418: { NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL, NULL, NULL, NULL }
1.32 markus 419: };
420:
421: /*--*/
1.1 deraadt 422:
1.37.2.1 jason 423: u_int
1.34 markus 424: cipher_mask_ssh1(int client)
1.1 deraadt 425: {
1.37.2.1 jason 426: u_int mask = 0;
1.34 markus 427: mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
428: mask |= 1 << SSH_CIPHER_BLOWFISH;
429: if (client) {
430: mask |= 1 << SSH_CIPHER_DES;
1.32 markus 431: }
432: return mask;
1.1 deraadt 433: }
434:
1.32 markus 435: Cipher *
436: cipher_by_name(const char *name)
437: {
438: Cipher *c;
439: for (c = ciphers; c->name != NULL; c++)
440: if (strcasecmp(c->name, name) == 0)
441: return c;
442: return NULL;
443: }
444:
445: Cipher *
446: cipher_by_number(int id)
447: {
448: Cipher *c;
449: for (c = ciphers; c->name != NULL; c++)
450: if (c->number == id)
451: return c;
452: return NULL;
453: }
1.24 markus 454:
455: #define CIPHER_SEP ","
456: int
457: ciphers_valid(const char *names)
458: {
1.32 markus 459: Cipher *c;
1.29 ho 460: char *ciphers, *cp;
1.24 markus 461: char *p;
462:
1.27 markus 463: if (names == NULL || strcmp(names, "") == 0)
1.24 markus 464: return 0;
1.29 ho 465: ciphers = cp = xstrdup(names);
1.32 markus 466: for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
1.29 ho 467: (p = strsep(&cp, CIPHER_SEP))) {
1.32 markus 468: c = cipher_by_name(p);
469: if (c == NULL || c->number != SSH_CIPHER_SSH2) {
470: debug("bad cipher %s [%s]", p, names);
1.24 markus 471: xfree(ciphers);
472: return 0;
1.32 markus 473: } else {
1.36 markus 474: debug3("cipher ok: %s [%s]", p, names);
1.24 markus 475: }
476: }
1.36 markus 477: debug3("ciphers ok: [%s]", names);
1.24 markus 478: xfree(ciphers);
479: return 1;
480: }
481:
1.18 markus 482: /*
483: * Parses the name of the cipher. Returns the number of the corresponding
484: * cipher, or -1 on error.
485: */
1.1 deraadt 486:
1.4 provos 487: int
488: cipher_number(const char *name)
1.1 deraadt 489: {
1.32 markus 490: Cipher *c;
1.27 markus 491: if (name == NULL)
492: return -1;
1.32 markus 493: c = cipher_by_name(name);
494: return (c==NULL) ? -1 : c->number;
1.1 deraadt 495: }
496:
1.32 markus 497: char *
498: cipher_name(int id)
1.1 deraadt 499: {
1.32 markus 500: Cipher *c = cipher_by_number(id);
501: return (c==NULL) ? "<unknown>" : c->name;
1.1 deraadt 502: }
503:
1.26 markus 504: void
1.32 markus 505: cipher_init(CipherContext *cc, Cipher *cipher,
506: const u_char *key, u_int keylen, const u_char *iv, u_int ivlen)
1.16 markus 507: {
1.32 markus 508: if (keylen < cipher->key_len)
509: fatal("cipher_init: key length %d is insufficient for %s.",
510: keylen, cipher->name);
511: if (iv != NULL && ivlen < cipher->block_size)
512: fatal("cipher_init: iv length %d is insufficient for %s.",
513: ivlen, cipher->name);
514: cc->cipher = cipher;
515: cipher->setkey(cc, key, keylen);
516: cipher->setiv(cc, iv, ivlen);
1.1 deraadt 517: }
1.21 markus 518:
1.26 markus 519: void
1.32 markus 520: cipher_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
521: {
522: if (len % cc->cipher->block_size)
523: fatal("cipher_encrypt: bad plaintext length %d", len);
524: cc->cipher->encrypt(cc, dest, src, len);
1.21 markus 525: }
526:
1.26 markus 527: void
1.32 markus 528: cipher_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.16 markus 529: {
1.32 markus 530: if (len % cc->cipher->block_size)
531: fatal("cipher_decrypt: bad ciphertext length %d", len);
532: cc->cipher->decrypt(cc, dest, src, len);
1.16 markus 533: }
1.1 deraadt 534:
1.32 markus 535: /*
536: * Selects the cipher, and keys if by computing the MD5 checksum of the
537: * passphrase and using the resulting 16 bytes as the key.
538: */
1.1 deraadt 539:
1.26 markus 540: void
1.32 markus 541: cipher_set_key_string(CipherContext *cc, Cipher *cipher,
542: const char *passphrase)
1.16 markus 543: {
1.32 markus 544: MD5_CTX md;
1.37.2.1 jason 545: u_char digest[16];
1.32 markus 546:
547: MD5_Init(&md);
548: MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase));
549: MD5_Final(digest, &md);
1.16 markus 550:
1.32 markus 551: cipher_init(cc, cipher, digest, 16, NULL, 0);
1.16 markus 552:
1.32 markus 553: memset(digest, 0, sizeof(digest));
554: memset(&md, 0, sizeof(md));
1.1 deraadt 555: }
![[BACK]](/icons/back.gif){kind=icon}
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