1 /*
2 * read_bignum():
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 *
5 * As far as I am concerned, the code I have written for this software
6 * can be used freely for any purpose. Any derived versions of this
7 * software must be clearly marked as such, and if the derived work is
8 * incompatible with the protocol description in the RFC file, it must be
9 * called by a name other than "ssh" or "Secure Shell".
10 *
11 *
12 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34 #include "includes.h"
35 RCSID("$OpenBSD: key.c,v 1.49 2002/09/09 14:54:14 markus Exp $");
36
37 #pragma ident "%Z%%M% %I% %E% SMI"
38
39 #include <openssl/evp.h>
40
41 #include "xmalloc.h"
42 #include "key.h"
43 #include "rsa.h"
44 #include "ssh-dss.h"
45 #include "ssh-rsa.h"
46 #include "uuencode.h"
47 #include "buffer.h"
48 #include "bufaux.h"
49 #include "log.h"
50
51 Key *
52 key_new(int type)
53 {
54 Key *k;
55 RSA *rsa;
56 DSA *dsa;
57 k = xmalloc(sizeof(*k));
58 k->type = type;
59 k->flags = 0;
60 k->dsa = NULL;
61 k->rsa = NULL;
62 switch (k->type) {
63 case KEY_RSA1:
64 case KEY_RSA:
65 if ((rsa = RSA_new()) == NULL)
66 fatal("key_new: RSA_new failed");
67 if ((rsa->n = BN_new()) == NULL)
68 fatal("key_new: BN_new failed");
69 if ((rsa->e = BN_new()) == NULL)
70 fatal("key_new: BN_new failed");
71 k->rsa = rsa;
72 break;
73 case KEY_DSA:
74 if ((dsa = DSA_new()) == NULL)
75 fatal("key_new: DSA_new failed");
76 if ((dsa->p = BN_new()) == NULL)
77 fatal("key_new: BN_new failed");
78 if ((dsa->q = BN_new()) == NULL)
79 fatal("key_new: BN_new failed");
80 if ((dsa->g = BN_new()) == NULL)
81 fatal("key_new: BN_new failed");
82 if ((dsa->pub_key = BN_new()) == NULL)
83 fatal("key_new: BN_new failed");
84 k->dsa = dsa;
85 break;
86 case KEY_UNSPEC:
87 break;
88 default:
89 fatal("key_new: bad key type %d", k->type);
90 break;
91 }
92 return k;
93 }
94
95 Key *
96 key_new_private(int type)
97 {
98 Key *k = key_new(type);
99 switch (k->type) {
100 case KEY_RSA1:
101 case KEY_RSA:
102 if ((k->rsa->d = BN_new()) == NULL)
103 fatal("key_new_private: BN_new failed");
104 if ((k->rsa->iqmp = BN_new()) == NULL)
105 fatal("key_new_private: BN_new failed");
106 if ((k->rsa->q = BN_new()) == NULL)
107 fatal("key_new_private: BN_new failed");
108 if ((k->rsa->p = BN_new()) == NULL)
109 fatal("key_new_private: BN_new failed");
110 if ((k->rsa->dmq1 = BN_new()) == NULL)
111 fatal("key_new_private: BN_new failed");
112 if ((k->rsa->dmp1 = BN_new()) == NULL)
113 fatal("key_new_private: BN_new failed");
114 break;
115 case KEY_DSA:
116 if ((k->dsa->priv_key = BN_new()) == NULL)
117 fatal("key_new_private: BN_new failed");
118 break;
119 case KEY_UNSPEC:
120 break;
121 default:
122 break;
123 }
124 return k;
125 }
126
127 void
128 key_free(Key *k)
129 {
130 switch (k->type) {
131 case KEY_RSA1:
132 case KEY_RSA:
133 if (k->rsa != NULL)
134 RSA_free(k->rsa);
135 k->rsa = NULL;
136 break;
137 case KEY_DSA:
138 if (k->dsa != NULL)
139 DSA_free(k->dsa);
140 k->dsa = NULL;
141 break;
142 case KEY_UNSPEC:
143 break;
144 default:
145 fatal("key_free: bad key type %d", k->type);
146 break;
147 }
148 xfree(k);
149 }
150 int
151 key_equal(const Key *a, const Key *b)
152 {
153 if (a == NULL || b == NULL || a->type != b->type)
154 return 0;
155 switch (a->type) {
156 case KEY_RSA1:
157 case KEY_RSA:
158 return a->rsa != NULL && b->rsa != NULL &&
159 BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
160 BN_cmp(a->rsa->n, b->rsa->n) == 0;
161 break;
162 case KEY_DSA:
163 return a->dsa != NULL && b->dsa != NULL &&
164 BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
165 BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
166 BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
167 BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
168 break;
169 default:
170 fatal("key_equal: bad key type %d", a->type);
171 break;
172 }
173 return 0;
174 }
175
176 static u_char *
177 key_fingerprint_raw(Key *k, enum fp_type dgst_type, u_int *dgst_raw_length)
178 {
179 const EVP_MD *md = NULL;
180 EVP_MD_CTX ctx;
181 u_char *blob = NULL;
182 u_char *retval = NULL;
183 u_int len = 0;
184 int nlen, elen;
185
186 *dgst_raw_length = 0;
187
188 switch (dgst_type) {
189 case SSH_FP_MD5:
190 md = EVP_md5();
191 break;
192 case SSH_FP_SHA1:
193 md = EVP_sha1();
194 break;
195 default:
196 fatal("key_fingerprint_raw: bad digest type %d",
197 dgst_type);
198 }
199 switch (k->type) {
200 case KEY_RSA1:
201 nlen = BN_num_bytes(k->rsa->n);
202 elen = BN_num_bytes(k->rsa->e);
203 len = nlen + elen;
204 blob = xmalloc(len);
205 BN_bn2bin(k->rsa->n, blob);
206 BN_bn2bin(k->rsa->e, blob + nlen);
207 break;
208 case KEY_DSA:
209 case KEY_RSA:
210 key_to_blob(k, &blob, &len);
211 break;
212 case KEY_UNSPEC:
213 return retval;
214 break;
215 default:
216 fatal("key_fingerprint_raw: bad key type %d", k->type);
217 break;
218 }
219 if (blob != NULL) {
220 retval = xmalloc(EVP_MAX_MD_SIZE);
221 EVP_DigestInit(&ctx, md);
222 EVP_DigestUpdate(&ctx, blob, len);
223 EVP_DigestFinal(&ctx, retval, dgst_raw_length);
224 memset(blob, 0, len);
225 xfree(blob);
226 } else {
227 fatal("key_fingerprint_raw: blob is null");
228 }
229 return retval;
230 }
231
232 static char *
233 key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
234 {
235 char *retval;
236 int i;
237
238 retval = xmalloc(dgst_raw_len * 3 + 1);
239 retval[0] = '\0';
240 for (i = 0; i < dgst_raw_len; i++) {
241 char hex[4];
242 snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
243 strlcat(retval, hex, dgst_raw_len * 3);
244 }
245 retval[(dgst_raw_len * 3) - 1] = '\0';
246 return retval;
247 }
248
249 static char *
250 key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
251 {
252 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
253 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
254 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
255 u_int i, j = 0, rounds, seed = 1;
256 char *retval;
257
258 rounds = (dgst_raw_len / 2) + 1;
259 retval = xmalloc(sizeof(char) * (rounds*6));
260 retval[j++] = 'x';
261 for (i = 0; i < rounds; i++) {
262 u_int idx0, idx1, idx2, idx3, idx4;
263 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
264 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
265 seed) % 6;
266 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
267 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
268 (seed / 6)) % 6;
269 retval[j++] = vowels[idx0];
270 retval[j++] = consonants[idx1];
271 retval[j++] = vowels[idx2];
272 if ((i + 1) < rounds) {
273 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
274 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
275 retval[j++] = consonants[idx3];
276 retval[j++] = '-';
277 retval[j++] = consonants[idx4];
278 seed = ((seed * 5) +
279 ((((u_int)(dgst_raw[2 * i])) * 7) +
280 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
281 }
282 } else {
283 idx0 = seed % 6;
284 idx1 = 16;
285 idx2 = seed / 6;
286 retval[j++] = vowels[idx0];
287 retval[j++] = consonants[idx1];
288 retval[j++] = vowels[idx2];
289 }
290 }
291 retval[j++] = 'x';
292 retval[j++] = '\0';
293 return retval;
294 }
295
296 char *
297 key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
298 {
299 char *retval = NULL;
300 u_char *dgst_raw;
301 u_int dgst_raw_len;
302
303 dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
304 if (!dgst_raw)
305 fatal("key_fingerprint: null from key_fingerprint_raw()");
306 switch (dgst_rep) {
307 case SSH_FP_HEX:
308 retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
309 break;
310 case SSH_FP_BUBBLEBABBLE:
311 retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
312 break;
313 default:
314 fatal("key_fingerprint_ex: bad digest representation %d",
315 dgst_rep);
316 break;
317 }
318 memset(dgst_raw, 0, dgst_raw_len);
319 xfree(dgst_raw);
320 return retval;
321 }
322
323 /*
324 * Reads a multiple-precision integer in decimal from the buffer, and advances
325 * the pointer. The integer must already be initialized. This function is
326 * permitted to modify the buffer. This leaves *cpp to point just beyond the
327 * last processed (and maybe modified) character. Note that this may modify
328 * the buffer containing the number.
329 */
330 static int
331 read_bignum(char **cpp, BIGNUM * value)
332 {
333 char *cp = *cpp;
334 int old;
335
336 /* Skip any leading whitespace. */
337 for (; *cp == ' ' || *cp == '\t'; cp++)
338 ;
339
340 /* Check that it begins with a decimal digit. */
341 if (*cp < '0' || *cp > '9')
342 return 0;
343
344 /* Save starting position. */
345 *cpp = cp;
346
347 /* Move forward until all decimal digits skipped. */
348 for (; *cp >= '0' && *cp <= '9'; cp++)
349 ;
350
351 /* Save the old terminating character, and replace it by \0. */
352 old = *cp;
353 *cp = 0;
354
355 /* Parse the number. */
356 if (BN_dec2bn(&value, *cpp) == 0)
357 return 0;
358
359 /* Restore old terminating character. */
360 *cp = old;
361
362 /* Move beyond the number and return success. */
363 *cpp = cp;
364 return 1;
365 }
366
367 static int
368 write_bignum(FILE *f, BIGNUM *num)
369 {
370 char *buf = BN_bn2dec(num);
371 if (buf == NULL) {
372 error("write_bignum: BN_bn2dec() failed");
373 return 0;
374 }
375 fprintf(f, " %s", buf);
376 OPENSSL_free(buf);
377 return 1;
378 }
379
380 /* returns 1 ok, -1 error */
381 int
382 key_read(Key *ret, char **cpp)
383 {
384 Key *k;
385 int success = -1;
386 char *cp, *space;
387 int len, n, type;
388 u_int bits;
389 u_char *blob;
390
391 cp = *cpp;
392
393 switch (ret->type) {
394 case KEY_RSA1:
395 /* Get number of bits. */
396 if (*cp < '0' || *cp > '9')
397 return -1; /* Bad bit count... */
398 for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
399 bits = 10 * bits + *cp - '0';
400 if (bits == 0)
401 return -1;
402 *cpp = cp;
403 /* Get public exponent, public modulus. */
404 if (!read_bignum(cpp, ret->rsa->e))
405 return -1;
406 if (!read_bignum(cpp, ret->rsa->n))
407 return -1;
408 success = 1;
409 break;
410 case KEY_UNSPEC:
411 case KEY_RSA:
412 case KEY_DSA:
413 space = strchr(cp, ' ');
414 if (space == NULL) {
415 debug3("key_read: no space");
416 return -1;
417 }
418 *space = '\0';
419 type = key_type_from_name(cp);
420 *space = ' ';
421 if (type == KEY_UNSPEC) {
422 debug3("key_read: no key found");
423 return -1;
424 }
425 cp = space+1;
426 if (*cp == '\0') {
427 debug3("key_read: short string");
428 return -1;
429 }
430 if (ret->type == KEY_UNSPEC) {
431 ret->type = type;
432 } else if (ret->type != type) {
433 /* is a key, but different type */
434 debug3("key_read: type mismatch");
435 return -1;
436 }
437 len = 2*strlen(cp);
438 blob = xmalloc(len);
439 n = uudecode(cp, blob, len);
440 if (n < 0) {
441 error("key_read: uudecode %s failed", cp);
442 xfree(blob);
443 return -1;
444 }
445 k = key_from_blob(blob, n);
446 xfree(blob);
447 if (k == NULL) {
448 error("key_read: key_from_blob %s failed", cp);
449 return -1;
450 }
451 if (k->type != type) {
452 error("key_read: type mismatch: encoding error");
453 key_free(k);
454 return -1;
455 }
456 /*XXXX*/
457 if (ret->type == KEY_RSA) {
458 if (ret->rsa != NULL)
459 RSA_free(ret->rsa);
460 ret->rsa = k->rsa;
461 k->rsa = NULL;
462 success = 1;
463 #ifdef DEBUG_PK
464 RSA_print_fp(stderr, ret->rsa, 8);
465 #endif
466 } else {
467 if (ret->dsa != NULL)
468 DSA_free(ret->dsa);
469 ret->dsa = k->dsa;
470 k->dsa = NULL;
471 success = 1;
472 #ifdef DEBUG_PK
473 DSA_print_fp(stderr, ret->dsa, 8);
474 #endif
475 }
476 /*XXXX*/
477 key_free(k);
478 if (success != 1)
479 break;
480 /* advance cp: skip whitespace and data */
481 while (*cp == ' ' || *cp == '\t')
482 cp++;
483 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
484 cp++;
485 *cpp = cp;
486 break;
487 default:
488 fatal("key_read: bad key type: %d", ret->type);
489 break;
490 }
491 return success;
492 }
493
494 int
495 key_write(const Key *key, FILE *f)
496 {
497 int n, success = 0;
498 u_int len, bits = 0;
499 u_char *blob;
500 char *uu;
501
502 if (key->type == KEY_RSA1 && key->rsa != NULL) {
503 /* size of modulus 'n' */
504 bits = BN_num_bits(key->rsa->n);
505 fprintf(f, "%u", bits);
506 if (write_bignum(f, key->rsa->e) &&
507 write_bignum(f, key->rsa->n)) {
508 success = 1;
509 } else {
510 error("key_write: failed for RSA key");
511 }
512 } else if ((key->type == KEY_DSA && key->dsa != NULL) ||
513 (key->type == KEY_RSA && key->rsa != NULL)) {
514 key_to_blob(key, &blob, &len);
515 uu = xmalloc(2*len);
516 n = uuencode(blob, len, uu, 2*len);
517 if (n > 0) {
518 fprintf(f, "%s %s", key_ssh_name(key), uu);
519 success = 1;
520 }
521 xfree(blob);
522 xfree(uu);
523 }
524 return success;
525 }
526
527 char *
528 key_type(Key *k)
529 {
530 switch (k->type) {
531 case KEY_RSA1:
532 return "RSA1";
533 break;
534 case KEY_RSA:
535 return "RSA";
536 break;
537 case KEY_DSA:
538 return "DSA";
539 break;
540 }
541 return "unknown";
542 }
543
544 char *
545 key_ssh_name(const Key *k)
546 {
547 switch (k->type) {
548 case KEY_RSA:
549 return "ssh-rsa";
550 break;
551 case KEY_DSA:
552 return "ssh-dss";
553 break;
554 }
555 return "ssh-unknown";
556 }
557
558 u_int
559 key_size(Key *k)
560 {
561 switch (k->type) {
562 case KEY_RSA1:
563 case KEY_RSA:
564 return BN_num_bits(k->rsa->n);
565 break;
566 case KEY_DSA:
567 return BN_num_bits(k->dsa->p);
568 break;
569 }
570 return 0;
571 }
572
573 static RSA *
574 rsa_generate_private_key(u_int bits)
575 {
576 RSA *private;
577 private = RSA_generate_key(bits, 35, NULL, NULL);
578 if (private == NULL)
579 fatal("rsa_generate_private_key: key generation failed.");
580 return private;
581 }
582
583 static DSA*
584 dsa_generate_private_key(u_int bits)
585 {
586 DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
587 if (private == NULL)
588 fatal("dsa_generate_private_key: DSA_generate_parameters failed");
589 if (!DSA_generate_key(private))
590 fatal("dsa_generate_private_key: DSA_generate_key failed.");
591 if (private == NULL)
592 fatal("dsa_generate_private_key: NULL.");
593 return private;
594 }
595
596 Key *
597 key_generate(int type, u_int bits)
598 {
599 Key *k = key_new(KEY_UNSPEC);
600 switch (type) {
601 case KEY_DSA:
602 k->dsa = dsa_generate_private_key(bits);
603 break;
604 case KEY_RSA:
605 case KEY_RSA1:
606 k->rsa = rsa_generate_private_key(bits);
607 break;
608 default:
609 fatal("key_generate: unknown type %d", type);
610 }
611 k->type = type;
612 return k;
613 }
614
615 Key *
616 key_from_private(Key *k)
617 {
618 Key *n = NULL;
619 switch (k->type) {
620 case KEY_DSA:
621 n = key_new(k->type);
622 BN_copy(n->dsa->p, k->dsa->p);
623 BN_copy(n->dsa->q, k->dsa->q);
624 BN_copy(n->dsa->g, k->dsa->g);
625 BN_copy(n->dsa->pub_key, k->dsa->pub_key);
626 break;
627 case KEY_RSA:
628 case KEY_RSA1:
629 n = key_new(k->type);
630 BN_copy(n->rsa->n, k->rsa->n);
631 BN_copy(n->rsa->e, k->rsa->e);
632 break;
633 default:
634 fatal("key_from_private: unknown type %d", k->type);
635 break;
636 }
637 return n;
638 }
639
640 int
641 key_type_from_name(char *name)
642 {
643 if (strcmp(name, "rsa1") == 0) {
644 return KEY_RSA1;
645 } else if (strcmp(name, "rsa") == 0) {
646 return KEY_RSA;
647 } else if (strcmp(name, "dsa") == 0) {
648 return KEY_DSA;
649 } else if (strcmp(name, "ssh-rsa") == 0) {
650 return KEY_RSA;
651 } else if (strcmp(name, "ssh-dss") == 0) {
652 return KEY_DSA;
653 } else if (strcmp(name, "null") == 0){
654 return KEY_NULL;
655 }
656 debug2("key_type_from_name: unknown key type '%s'", name);
657 return KEY_UNSPEC;
658 }
659
660 int
661 key_names_valid2(const char *names)
662 {
663 char *s, *cp, *p;
664
665 if (names == NULL || strcmp(names, "") == 0)
666 return 0;
667 s = cp = xstrdup(names);
668 for ((p = strsep(&cp, ",")); p && *p != '\0';
669 (p = strsep(&cp, ","))) {
670 switch (key_type_from_name(p)) {
671 case KEY_RSA1:
672 case KEY_UNSPEC:
673 xfree(s);
674 return 0;
675 }
676 }
677 debug3("key names ok: [%s]", names);
678 xfree(s);
679 return 1;
680 }
681
682 Key *
683 key_from_blob(u_char *blob, int blen)
684 {
685 Buffer b;
686 char *ktype;
687 int rlen, type;
688 Key *key = NULL;
689
690 #ifdef DEBUG_PK
691 dump_base64(stderr, blob, blen);
692 #endif
693 buffer_init(&b);
694 buffer_append(&b, blob, blen);
695 if ((ktype = buffer_get_string_ret(&b, NULL)) == NULL) {
696 error("key_from_blob: can't read key type");
697 goto out;
698 }
699
700 type = key_type_from_name(ktype);
701
702 switch (type) {
703 case KEY_RSA:
704 key = key_new(type);
705 if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
706 buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
707 error("key_from_blob: can't read rsa key");
708 key_free(key);
709 key = NULL;
710 goto out;
711 }
712 #ifdef DEBUG_PK
713 RSA_print_fp(stderr, key->rsa, 8);
714 #endif
715 break;
716 case KEY_DSA:
717 key = key_new(type);
718 if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
719 buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
720 buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
721 buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
722 error("key_from_blob: can't read dsa key");
723 key_free(key);
724 key = NULL;
725 goto out;
726 }
727 #ifdef DEBUG_PK
728 DSA_print_fp(stderr, key->dsa, 8);
729 #endif
730 break;
731 case KEY_UNSPEC:
732 key = key_new(type);
733 break;
734 default:
735 error("key_from_blob: cannot handle type %s", ktype);
736 goto out;
737 }
738 rlen = buffer_len(&b);
739 if (key != NULL && rlen != 0)
740 error("key_from_blob: remaining bytes in key blob %d", rlen);
741 out:
742 if (ktype != NULL)
743 xfree(ktype);
744 buffer_free(&b);
745 return key;
746 }
747
748 int
749 key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
750 {
751 Buffer b;
752 int len;
753
754 if (key == NULL) {
755 error("key_to_blob: key == NULL");
756 return 0;
757 }
758 buffer_init(&b);
759 switch (key->type) {
760 case KEY_DSA:
761 buffer_put_cstring(&b, key_ssh_name(key));
762 buffer_put_bignum2(&b, key->dsa->p);
763 buffer_put_bignum2(&b, key->dsa->q);
764 buffer_put_bignum2(&b, key->dsa->g);
765 buffer_put_bignum2(&b, key->dsa->pub_key);
766 break;
767 case KEY_RSA:
768 buffer_put_cstring(&b, key_ssh_name(key));
769 buffer_put_bignum2(&b, key->rsa->e);
770 buffer_put_bignum2(&b, key->rsa->n);
771 break;
772 default:
773 error("key_to_blob: unsupported key type %d", key->type);
774 buffer_free(&b);
775 return 0;
776 }
777 len = buffer_len(&b);
778 if (lenp != NULL)
779 *lenp = len;
780 if (blobp != NULL) {
781 *blobp = xmalloc(len);
782 memcpy(*blobp, buffer_ptr(&b), len);
783 }
784 memset(buffer_ptr(&b), 0, len);
785 buffer_free(&b);
786 return len;
787 }
788
789 int
790 key_sign(
791 Key *key,
792 u_char **sigp, u_int *lenp,
793 u_char *data, u_int datalen)
794 {
795 switch (key->type) {
796 case KEY_DSA:
797 return ssh_dss_sign(key, sigp, lenp, data, datalen);
798 break;
799 case KEY_RSA:
800 return ssh_rsa_sign(key, sigp, lenp, data, datalen);
801 break;
802 default:
803 error("key_sign: illegal key type %d", key->type);
804 return -1;
805 break;
806 }
807 }
808
809 /*
810 * key_verify returns 1 for a correct signature, 0 for an incorrect signature
811 * and -1 on error.
812 */
813 int
814 key_verify(
815 Key *key,
816 u_char *signature, u_int signaturelen,
817 u_char *data, u_int datalen)
818 {
819 if (signaturelen == 0)
820 return -1;
821
822 switch (key->type) {
823 case KEY_DSA:
824 return ssh_dss_verify(key, signature, signaturelen, data, datalen);
825 break;
826 case KEY_RSA:
827 return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
828 break;
829 default:
830 error("key_verify: illegal key type %d", key->type);
831 return -1;
832 break;
833 }
834 }
835
836 /* Converts a private to a public key */
837 Key *
838 key_demote(Key *k)
839 {
840 Key *pk;
841
842 pk = xmalloc(sizeof(*pk));
843 pk->type = k->type;
844 pk->flags = k->flags;
845 pk->dsa = NULL;
846 pk->rsa = NULL;
847
848 switch (k->type) {
849 case KEY_RSA1:
850 case KEY_RSA:
851 if ((pk->rsa = RSA_new()) == NULL)
852 fatal("key_demote: RSA_new failed");
853 if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
854 fatal("key_demote: BN_dup failed");
855 if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
856 fatal("key_demote: BN_dup failed");
857 break;
858 case KEY_DSA:
859 if ((pk->dsa = DSA_new()) == NULL)
860 fatal("key_demote: DSA_new failed");
861 if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
862 fatal("key_demote: BN_dup failed");
863 if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
864 fatal("key_demote: BN_dup failed");
865 if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
866 fatal("key_demote: BN_dup failed");
867 if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
868 fatal("key_demote: BN_dup failed");
869 break;
870 default:
871 fatal("key_free: bad key type %d", k->type);
872 break;
873 }
874
875 return (pk);
876 }