Annotation of src/usr.bin/ssh/cipher.c, Revision 1.41
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"
1.41 ! markus 38: RCSID("$OpenBSD: cipher.c,v 1.40 2000/12/09 13:41:52 markus Exp $");
1.1 deraadt 39:
40: #include "ssh.h"
1.24 markus 41: #include "xmalloc.h"
1.8 deraadt 42:
1.25 markus 43: #include <openssl/md5.h>
1.1 deraadt 44:
1.32 markus 45:
46: /* no encryption */
47: void
48: none_setkey(CipherContext *cc, const u_char *key, u_int keylen)
49: {
50: }
51: void
52: none_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
53: {
54: }
55: void
56: none_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
57: {
58: memcpy(dest, src, len);
59: }
60:
61: /* DES */
62: void
63: des_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
64: {
1.34 markus 65: static int dowarn = 1;
66: if (dowarn) {
67: error("Warning: use of DES is strongly discouraged "
68: "due to cryptographic weaknesses");
69: dowarn = 0;
70: }
1.32 markus 71: des_set_key((void *)key, cc->u.des.key);
72: }
73: void
74: des_ssh1_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
75: {
76: memset(cc->u.des.iv, 0, sizeof(cc->u.des.iv));
77: }
78: void
79: des_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
80: {
81: des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
82: DES_ENCRYPT);
83: }
84: void
85: des_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
86: {
87: des_ncbc_encrypt(src, dest, len, cc->u.des.key, &cc->u.des.iv,
88: DES_DECRYPT);
89: }
90:
91: /* 3DES */
92: void
93: des3_setkey(CipherContext *cc, const u_char *key, u_int keylen)
94: {
95: des_set_key((void *) key, cc->u.des3.key1);
96: des_set_key((void *) (key+8), cc->u.des3.key2);
97: des_set_key((void *) (key+16), cc->u.des3.key3);
98: }
99: void
100: des3_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
101: {
102: memset(cc->u.des3.iv2, 0, sizeof(cc->u.des3.iv2));
103: memset(cc->u.des3.iv3, 0, sizeof(cc->u.des3.iv3));
104: if (iv == NULL)
105: return;
106: memcpy(cc->u.des3.iv3, (char *)iv, 8);
107: }
108: void
109: des3_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
110: {
111: des_ede3_cbc_encrypt(src, dest, len,
112: cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
113: &cc->u.des3.iv3, DES_ENCRYPT);
114: }
115: void
116: des3_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
117: {
118: des_ede3_cbc_encrypt(src, dest, len,
119: cc->u.des3.key1, cc->u.des3.key2, cc->u.des3.key3,
120: &cc->u.des3.iv3, DES_DECRYPT);
121: }
122:
1.1 deraadt 123: /*
1.24 markus 124: * This is used by SSH1:
125: *
1.23 deraadt 126: * What kind of triple DES are these 2 routines?
1.1 deraadt 127: *
128: * Why is there a redundant initialization vector?
129: *
130: * If only iv3 was used, then, this would till effect have been
131: * outer-cbc. However, there is also a private iv1 == iv2 which
132: * perhaps makes differential analysis easier. On the other hand, the
133: * private iv1 probably makes the CRC-32 attack ineffective. This is a
134: * result of that there is no longer any known iv1 to use when
135: * choosing the X block.
136: */
137: void
1.32 markus 138: des3_ssh1_setkey(CipherContext *cc, const u_char *key, u_int keylen)
139: {
140: des_set_key((void *) key, cc->u.des3.key1);
141: des_set_key((void *) (key+8), cc->u.des3.key2);
142: if (keylen <= 16)
143: des_set_key((void *) key, cc->u.des3.key3);
144: else
145: des_set_key((void *) (key+16), cc->u.des3.key3);
146: }
147: void
148: des3_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
149: u_int len)
1.1 deraadt 150: {
1.16 markus 151: des_cblock iv1;
1.32 markus 152: des_cblock *iv2 = &cc->u.des3.iv2;
153: des_cblock *iv3 = &cc->u.des3.iv3;
1.1 deraadt 154:
1.16 markus 155: memcpy(&iv1, iv2, 8);
1.1 deraadt 156:
1.38 markus 157: des_ncbc_encrypt(src, dest, len, cc->u.des3.key1, &iv1, DES_ENCRYPT);
158: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_DECRYPT);
159: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key3, iv3, DES_ENCRYPT);
1.1 deraadt 160: }
161: void
1.32 markus 162: des3_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
163: u_int len)
1.1 deraadt 164: {
1.16 markus 165: des_cblock iv1;
1.32 markus 166: des_cblock *iv2 = &cc->u.des3.iv2;
167: des_cblock *iv3 = &cc->u.des3.iv3;
1.1 deraadt 168:
1.16 markus 169: memcpy(&iv1, iv2, 8);
1.1 deraadt 170:
1.38 markus 171: des_ncbc_encrypt(src, dest, len, cc->u.des3.key3, iv3, DES_DECRYPT);
172: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key2, iv2, DES_ENCRYPT);
173: des_ncbc_encrypt(dest, dest, len, cc->u.des3.key1, &iv1, DES_DECRYPT);
1.1 deraadt 174: }
175:
1.32 markus 176: /* Blowfish */
177: void
178: blowfish_setkey(CipherContext *cc, const u_char *key, u_int keylen)
179: {
1.41 ! markus 180: BF_set_key(&cc->u.bf.key, keylen, (u_char *)key);
1.32 markus 181: }
182: void
183: blowfish_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
184: {
185: if (iv == NULL)
186: memset(cc->u.bf.iv, 0, 8);
187: else
188: memcpy(cc->u.bf.iv, (char *)iv, 8);
189: }
190: void
191: blowfish_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
192: u_int len)
193: {
194: BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
195: BF_ENCRYPT);
196: }
197: void
198: blowfish_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
199: u_int len)
200: {
201: BF_cbc_encrypt((void *)src, dest, len, &cc->u.bf.key, cc->u.bf.iv,
202: BF_DECRYPT);
203: }
204:
1.1 deraadt 205: /*
1.24 markus 206: * SSH1 uses a variation on Blowfish, all bytes must be swapped before
1.1 deraadt 207: * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
208: */
1.16 markus 209: static void
1.41 ! markus 210: swap_bytes(const u_char *src, u_char *dst, int n)
1.1 deraadt 211: {
1.37 markus 212: char c[4];
213:
214: /* Process 4 bytes every lap. */
215: for (n = n / 4; n > 0; n--) {
216: c[3] = *src++;
217: c[2] = *src++;
218: c[1] = *src++;
219: c[0] = *src++;
220:
221: *dst++ = c[0];
222: *dst++ = c[1];
223: *dst++ = c[2];
224: *dst++ = c[3];
1.16 markus 225: }
1.1 deraadt 226: }
227:
1.32 markus 228: void
229: blowfish_ssh1_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
230: u_int len)
231: {
232: swap_bytes(src, dest, len);
233: BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
234: BF_ENCRYPT);
235: swap_bytes(dest, dest, len);
236: }
237: void
238: blowfish_ssh1_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
239: u_int len)
1.4 provos 240: {
1.32 markus 241: swap_bytes(src, dest, len);
242: BF_cbc_encrypt((void *)dest, dest, len, &cc->u.bf.key, cc->u.bf.iv,
243: BF_DECRYPT);
244: swap_bytes(dest, dest, len);
245: }
1.1 deraadt 246:
1.32 markus 247: /* alleged rc4 */
248: void
249: arcfour_setkey(CipherContext *cc, const u_char *key, u_int keylen)
250: {
251: RC4_set_key(&cc->u.rc4, keylen, (u_char *)key);
252: }
253: void
254: arcfour_crypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
255: {
256: RC4(&cc->u.rc4, len, (u_char *)src, dest);
257: }
1.1 deraadt 258:
1.32 markus 259: /* CAST */
260: void
261: cast_setkey(CipherContext *cc, const u_char *key, u_int keylen)
262: {
1.41 ! markus 263: CAST_set_key(&cc->u.cast.key, keylen, (u_char *) key);
1.32 markus 264: }
265: void
266: cast_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
1.1 deraadt 267: {
1.32 markus 268: if (iv == NULL)
269: fatal("no IV for %s.", cc->cipher->name);
270: memcpy(cc->u.cast.iv, (char *)iv, 8);
1.22 markus 271: }
1.32 markus 272: void
273: cast_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.22 markus 274: {
1.32 markus 275: CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
276: CAST_ENCRYPT);
1.1 deraadt 277: }
1.32 markus 278: void
279: cast_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.22 markus 280: {
1.32 markus 281: CAST_cbc_encrypt(src, dest, len, &cc->u.cast.key, cc->u.cast.iv,
282: CAST_DECRYPT);
1.22 markus 283: }
1.1 deraadt 284:
1.35 markus 285: /* RIJNDAEL */
286:
287: #define RIJNDAEL_BLOCKSIZE 16
288: void
289: rijndael_setkey(CipherContext *cc, const u_char *key, u_int keylen)
290: {
1.40 markus 291: rijndael_set_key(&cc->u.rijndael.enc, (u4byte *)key, 8*keylen, 1);
292: rijndael_set_key(&cc->u.rijndael.dec, (u4byte *)key, 8*keylen, 0);
1.35 markus 293: }
294: void
295: rijndael_setiv(CipherContext *cc, const u_char *iv, u_int ivlen)
296: {
1.40 markus 297: if (iv == NULL)
298: fatal("no IV for %s.", cc->cipher->name);
299: memcpy((u_char *)cc->u.rijndael.iv, iv, RIJNDAEL_BLOCKSIZE);
1.35 markus 300: }
301: void
302: rijndael_cbc_encrypt(CipherContext *cc, u_char *dest, const u_char *src,
303: u_int len)
304: {
1.40 markus 305: rijndael_ctx *ctx = &cc->u.rijndael.enc;
306: u4byte *iv = cc->u.rijndael.iv;
307: u4byte in[4];
308: u4byte *cprev, *cnow, *plain;
309: int i, blocks = len / RIJNDAEL_BLOCKSIZE;
1.35 markus 310: if (len == 0)
311: return;
312: if (len % RIJNDAEL_BLOCKSIZE)
313: fatal("rijndael_cbc_encrypt: bad len %d", len);
1.40 markus 314: cnow = (u4byte*) dest;
315: plain = (u4byte*) src;
1.35 markus 316: cprev = iv;
1.40 markus 317: for(i = 0; i < blocks; i++, plain+=4, cnow+=4) {
318: in[0] = plain[0] ^ cprev[0];
319: in[1] = plain[1] ^ cprev[1];
320: in[2] = plain[2] ^ cprev[2];
321: in[3] = plain[3] ^ cprev[3];
1.35 markus 322: rijndael_encrypt(ctx, in, cnow);
323: cprev = cnow;
324: }
325: memcpy(iv, cprev, RIJNDAEL_BLOCKSIZE);
326: }
327:
328: void
329: rijndael_cbc_decrypt(CipherContext *cc, u_char *dest, const u_char *src,
330: u_int len)
331: {
1.40 markus 332: rijndael_ctx *ctx = &cc->u.rijndael.dec;
333: u4byte *iv = cc->u.rijndael.iv;
334: u4byte ivsaved[4];
335: u4byte *cnow = (u4byte*) (src+len-RIJNDAEL_BLOCKSIZE);
336: u4byte *plain = (u4byte*) (dest+len-RIJNDAEL_BLOCKSIZE);
337: u4byte *ivp;
338: int i, blocks = len / RIJNDAEL_BLOCKSIZE;
1.35 markus 339: if (len == 0)
340: return;
341: if (len % RIJNDAEL_BLOCKSIZE)
342: fatal("rijndael_cbc_decrypt: bad len %d", len);
343: memcpy(ivsaved, cnow, RIJNDAEL_BLOCKSIZE);
1.40 markus 344: for(i = blocks; i > 0; i--, cnow-=4, plain-=4) {
1.35 markus 345: rijndael_decrypt(ctx, cnow, plain);
1.40 markus 346: ivp = (i == 1) ? iv : cnow-4;
347: plain[0] ^= ivp[0];
348: plain[1] ^= ivp[1];
349: plain[2] ^= ivp[2];
350: plain[3] ^= ivp[3];
1.35 markus 351: }
352: memcpy(iv, ivsaved, RIJNDAEL_BLOCKSIZE);
353: }
1.32 markus 354:
355: Cipher ciphers[] = {
356: { "none",
357: SSH_CIPHER_NONE, 8, 0,
358: none_setkey, none_setiv,
359: none_crypt, none_crypt },
1.34 markus 360: { "des",
361: SSH_CIPHER_DES, 8, 8,
362: des_ssh1_setkey, des_ssh1_setiv,
363: des_ssh1_encrypt, des_ssh1_decrypt },
1.32 markus 364: { "3des",
365: SSH_CIPHER_3DES, 8, 16,
366: des3_ssh1_setkey, des3_setiv,
367: des3_ssh1_encrypt, des3_ssh1_decrypt },
368: { "blowfish",
369: SSH_CIPHER_BLOWFISH, 8, 16,
370: blowfish_setkey, blowfish_setiv,
371: blowfish_ssh1_encrypt, blowfish_ssh1_decrypt },
372:
373: { "3des-cbc",
374: SSH_CIPHER_SSH2, 8, 24,
375: des3_setkey, des3_setiv,
376: des3_cbc_encrypt, des3_cbc_decrypt },
377: { "blowfish-cbc",
378: SSH_CIPHER_SSH2, 8, 16,
379: blowfish_setkey, blowfish_setiv,
380: blowfish_cbc_encrypt, blowfish_cbc_decrypt },
381: { "cast128-cbc",
382: SSH_CIPHER_SSH2, 8, 16,
383: cast_setkey, cast_setiv,
384: cast_cbc_encrypt, cast_cbc_decrypt },
385: { "arcfour",
386: SSH_CIPHER_SSH2, 8, 16,
387: arcfour_setkey, none_setiv,
388: arcfour_crypt, arcfour_crypt },
1.35 markus 389: { "aes128-cbc",
390: SSH_CIPHER_SSH2, 16, 16,
391: rijndael_setkey, rijndael_setiv,
392: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
393: { "aes192-cbc",
394: SSH_CIPHER_SSH2, 16, 24,
395: rijndael_setkey, rijndael_setiv,
396: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
397: { "aes256-cbc",
398: SSH_CIPHER_SSH2, 16, 32,
399: rijndael_setkey, rijndael_setiv,
400: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
401: { "rijndael128-cbc",
402: SSH_CIPHER_SSH2, 16, 16,
403: rijndael_setkey, rijndael_setiv,
404: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
405: { "rijndael192-cbc",
406: SSH_CIPHER_SSH2, 16, 24,
407: rijndael_setkey, rijndael_setiv,
408: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
409: { "rijndael256-cbc",
410: SSH_CIPHER_SSH2, 16, 32,
411: rijndael_setkey, rijndael_setiv,
412: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
413: { "rijndael-cbc@lysator.liu.se",
414: SSH_CIPHER_SSH2, 16, 32,
415: rijndael_setkey, rijndael_setiv,
416: rijndael_cbc_encrypt, rijndael_cbc_decrypt },
1.32 markus 417: { NULL, SSH_CIPHER_ILLEGAL, 0, 0, NULL, NULL, NULL, NULL }
418: };
419:
420: /*--*/
1.1 deraadt 421:
1.41 ! markus 422: u_int
1.34 markus 423: cipher_mask_ssh1(int client)
1.1 deraadt 424: {
1.41 ! markus 425: u_int mask = 0;
1.34 markus 426: mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
427: mask |= 1 << SSH_CIPHER_BLOWFISH;
428: if (client) {
429: mask |= 1 << SSH_CIPHER_DES;
1.32 markus 430: }
431: return mask;
1.1 deraadt 432: }
433:
1.32 markus 434: Cipher *
435: cipher_by_name(const char *name)
436: {
437: Cipher *c;
438: for (c = ciphers; c->name != NULL; c++)
439: if (strcasecmp(c->name, name) == 0)
440: return c;
441: return NULL;
442: }
443:
444: Cipher *
445: cipher_by_number(int id)
446: {
447: Cipher *c;
448: for (c = ciphers; c->name != NULL; c++)
449: if (c->number == id)
450: return c;
451: return NULL;
452: }
1.24 markus 453:
454: #define CIPHER_SEP ","
455: int
456: ciphers_valid(const char *names)
457: {
1.32 markus 458: Cipher *c;
1.29 ho 459: char *ciphers, *cp;
1.24 markus 460: char *p;
461:
1.27 markus 462: if (names == NULL || strcmp(names, "") == 0)
1.24 markus 463: return 0;
1.29 ho 464: ciphers = cp = xstrdup(names);
1.32 markus 465: for ((p = strsep(&cp, CIPHER_SEP)); p && *p != '\0';
1.29 ho 466: (p = strsep(&cp, CIPHER_SEP))) {
1.32 markus 467: c = cipher_by_name(p);
468: if (c == NULL || c->number != SSH_CIPHER_SSH2) {
469: debug("bad cipher %s [%s]", p, names);
1.24 markus 470: xfree(ciphers);
471: return 0;
1.32 markus 472: } else {
1.36 markus 473: debug3("cipher ok: %s [%s]", p, names);
1.24 markus 474: }
475: }
1.36 markus 476: debug3("ciphers ok: [%s]", names);
1.24 markus 477: xfree(ciphers);
478: return 1;
479: }
480:
1.18 markus 481: /*
482: * Parses the name of the cipher. Returns the number of the corresponding
483: * cipher, or -1 on error.
484: */
1.1 deraadt 485:
1.4 provos 486: int
487: cipher_number(const char *name)
1.1 deraadt 488: {
1.32 markus 489: Cipher *c;
1.27 markus 490: if (name == NULL)
491: return -1;
1.32 markus 492: c = cipher_by_name(name);
493: return (c==NULL) ? -1 : c->number;
1.1 deraadt 494: }
495:
1.32 markus 496: char *
497: cipher_name(int id)
1.1 deraadt 498: {
1.32 markus 499: Cipher *c = cipher_by_number(id);
500: return (c==NULL) ? "<unknown>" : c->name;
1.1 deraadt 501: }
502:
1.26 markus 503: void
1.32 markus 504: cipher_init(CipherContext *cc, Cipher *cipher,
505: const u_char *key, u_int keylen, const u_char *iv, u_int ivlen)
1.16 markus 506: {
1.32 markus 507: if (keylen < cipher->key_len)
508: fatal("cipher_init: key length %d is insufficient for %s.",
509: keylen, cipher->name);
510: if (iv != NULL && ivlen < cipher->block_size)
511: fatal("cipher_init: iv length %d is insufficient for %s.",
512: ivlen, cipher->name);
513: cc->cipher = cipher;
514: cipher->setkey(cc, key, keylen);
515: cipher->setiv(cc, iv, ivlen);
1.1 deraadt 516: }
1.21 markus 517:
1.26 markus 518: void
1.32 markus 519: cipher_encrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
520: {
521: if (len % cc->cipher->block_size)
522: fatal("cipher_encrypt: bad plaintext length %d", len);
523: cc->cipher->encrypt(cc, dest, src, len);
1.21 markus 524: }
525:
1.26 markus 526: void
1.32 markus 527: cipher_decrypt(CipherContext *cc, u_char *dest, const u_char *src, u_int len)
1.16 markus 528: {
1.32 markus 529: if (len % cc->cipher->block_size)
530: fatal("cipher_decrypt: bad ciphertext length %d", len);
531: cc->cipher->decrypt(cc, dest, src, len);
1.16 markus 532: }
1.1 deraadt 533:
1.32 markus 534: /*
535: * Selects the cipher, and keys if by computing the MD5 checksum of the
536: * passphrase and using the resulting 16 bytes as the key.
537: */
1.1 deraadt 538:
1.26 markus 539: void
1.32 markus 540: cipher_set_key_string(CipherContext *cc, Cipher *cipher,
541: const char *passphrase)
1.16 markus 542: {
1.32 markus 543: MD5_CTX md;
1.41 ! markus 544: u_char digest[16];
1.32 markus 545:
546: MD5_Init(&md);
547: MD5_Update(&md, (const u_char *)passphrase, strlen(passphrase));
548: MD5_Final(digest, &md);
1.16 markus 549:
1.32 markus 550: cipher_init(cc, cipher, digest, 16, NULL, 0);
1.16 markus 551:
1.32 markus 552: memset(digest, 0, sizeof(digest));
553: memset(&md, 0, sizeof(md));
1.1 deraadt 554: }
![[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