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/opensslconf.h>
40 #include <openssl/evp.h>
41
42 #include "xmalloc.h"
43 #include "key.h"
44 #include "rsa.h"
45 #include "ssh-dss.h"
46 #include "ssh-rsa.h"
47 #include "uuencode.h"
48 #include "buffer.h"
49 #include "bufaux.h"
50 #include "log.h"
51
52 Key *
53 key_new(int type)
54 {
55 Key *k;
56 RSA *rsa;
57 DSA *dsa;
58 k = xmalloc(sizeof(*k));
59 k->type = type;
60 k->flags = 0;
61 k->dsa = NULL;
62 k->rsa = NULL;
63 switch (k->type) {
64 case KEY_RSA1:
65 case KEY_RSA:
66 if ((rsa = RSA_new()) == NULL)
67 fatal("key_new: RSA_new failed");
68 if ((rsa->n = BN_new()) == NULL)
69 fatal("key_new: BN_new failed");
70 if ((rsa->e = BN_new()) == NULL)
71 fatal("key_new: BN_new failed");
72 k->rsa = rsa;
73 break;
74 case KEY_DSA:
75 if ((dsa = DSA_new()) == NULL)
76 fatal("key_new: DSA_new failed");
77 if ((dsa->p = BN_new()) == NULL)
78 fatal("key_new: BN_new failed");
79 if ((dsa->q = BN_new()) == NULL)
80 fatal("key_new: BN_new failed");
81 if ((dsa->g = BN_new()) == NULL)
82 fatal("key_new: BN_new failed");
83 if ((dsa->pub_key = BN_new()) == NULL)
84 fatal("key_new: BN_new failed");
85 k->dsa = dsa;
86 break;
87 case KEY_UNSPEC:
88 break;
89 default:
90 fatal("key_new: bad key type %d", k->type);
91 break;
92 }
93 return k;
94 }
95
96 Key *
97 key_new_private(int type)
98 {
99 Key *k = key_new(type);
100 switch (k->type) {
101 case KEY_RSA1:
102 case KEY_RSA:
103 if ((k->rsa->d = BN_new()) == NULL)
104 fatal("key_new_private: BN_new failed");
105 if ((k->rsa->iqmp = BN_new()) == NULL)
106 fatal("key_new_private: BN_new failed");
107 if ((k->rsa->q = BN_new()) == NULL)
108 fatal("key_new_private: BN_new failed");
109 if ((k->rsa->p = BN_new()) == NULL)
110 fatal("key_new_private: BN_new failed");
111 if ((k->rsa->dmq1 = BN_new()) == NULL)
112 fatal("key_new_private: BN_new failed");
113 if ((k->rsa->dmp1 = BN_new()) == NULL)
114 fatal("key_new_private: BN_new failed");
115 break;
116 case KEY_DSA:
117 if ((k->dsa->priv_key = BN_new()) == NULL)
118 fatal("key_new_private: BN_new failed");
119 break;
120 case KEY_UNSPEC:
121 break;
122 default:
123 break;
124 }
125 return k;
126 }
127
128 void
129 key_free(Key *k)
130 {
131 switch (k->type) {
132 case KEY_RSA1:
133 case KEY_RSA:
134 if (k->rsa != NULL)
135 RSA_free(k->rsa);
136 k->rsa = NULL;
137 break;
138 case KEY_DSA:
139 if (k->dsa != NULL)
140 DSA_free(k->dsa);
141 k->dsa = NULL;
142 break;
143 case KEY_UNSPEC:
144 break;
145 default:
146 fatal("key_free: bad key type %d", k->type);
147 break;
148 }
149 xfree(k);
150 }
151 int
152 key_equal(const Key *a, const Key *b)
153 {
154 if (a == NULL || b == NULL || a->type != b->type)
155 return 0;
156 switch (a->type) {
157 case KEY_RSA1:
158 case KEY_RSA:
159 return a->rsa != NULL && b->rsa != NULL &&
160 BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
161 BN_cmp(a->rsa->n, b->rsa->n) == 0;
162 break;
163 case KEY_DSA:
164 return a->dsa != NULL && b->dsa != NULL &&
165 BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
166 BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
167 BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
168 BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
169 break;
170 default:
171 fatal("key_equal: bad key type %d", a->type);
172 break;
173 }
174 return 0;
175 }
176
177 static u_char *
178 key_fingerprint_raw(Key *k, enum fp_type dgst_type, u_int *dgst_raw_length)
179 {
180 const EVP_MD *md = NULL;
181 EVP_MD_CTX ctx;
182 u_char *blob = NULL;
183 u_char *retval = NULL;
184 u_int len = 0;
185 int nlen, elen;
186
187 *dgst_raw_length = 0;
188
189 switch (dgst_type) {
190 case SSH_FP_MD5:
191 md = EVP_md5();
192 break;
193 case SSH_FP_SHA1:
194 md = EVP_sha1();
195 break;
196 default:
197 fatal("key_fingerprint_raw: bad digest type %d",
198 dgst_type);
199 }
200 switch (k->type) {
201 case KEY_RSA1:
202 nlen = BN_num_bytes(k->rsa->n);
203 elen = BN_num_bytes(k->rsa->e);
204 len = nlen + elen;
205 blob = xmalloc(len);
206 BN_bn2bin(k->rsa->n, blob);
207 BN_bn2bin(k->rsa->e, blob + nlen);
208 break;
209 case KEY_DSA:
210 case KEY_RSA:
211 key_to_blob(k, &blob, &len);
212 break;
213 case KEY_UNSPEC:
214 return retval;
215 break;
216 default:
217 fatal("key_fingerprint_raw: bad key type %d", k->type);
218 break;
219 }
220 if (blob != NULL) {
221 retval = xmalloc(EVP_MAX_MD_SIZE);
222 EVP_DigestInit(&ctx, md);
223 EVP_DigestUpdate(&ctx, blob, len);
224 EVP_DigestFinal(&ctx, retval, dgst_raw_length);
225 memset(blob, 0, len);
226 xfree(blob);
227 } else {
228 fatal("key_fingerprint_raw: blob is null");
229 }
230 return retval;
231 }
232
233 static char *
234 key_fingerprint_hex(u_char *dgst_raw, u_int dgst_raw_len)
235 {
236 char *retval;
237 int i;
238
239 retval = xmalloc(dgst_raw_len * 3 + 1);
240 retval[0] = '\0';
241 for (i = 0; i < dgst_raw_len; i++) {
242 char hex[4];
243 snprintf(hex, sizeof(hex), "%02x:", dgst_raw[i]);
244 strlcat(retval, hex, dgst_raw_len * 3);
245 }
246 retval[(dgst_raw_len * 3) - 1] = '\0';
247 return retval;
248 }
249
250 static char *
251 key_fingerprint_bubblebabble(u_char *dgst_raw, u_int dgst_raw_len)
252 {
253 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
254 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
255 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
256 u_int i, j = 0, rounds, seed = 1;
257 char *retval;
258
259 rounds = (dgst_raw_len / 2) + 1;
260 retval = xmalloc(sizeof(char) * (rounds*6));
261 retval[j++] = 'x';
262 for (i = 0; i < rounds; i++) {
263 u_int idx0, idx1, idx2, idx3, idx4;
264 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
265 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
266 seed) % 6;
267 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
268 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
269 (seed / 6)) % 6;
270 retval[j++] = vowels[idx0];
271 retval[j++] = consonants[idx1];
272 retval[j++] = vowels[idx2];
273 if ((i + 1) < rounds) {
274 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
275 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
276 retval[j++] = consonants[idx3];
277 retval[j++] = '-';
278 retval[j++] = consonants[idx4];
279 seed = ((seed * 5) +
280 ((((u_int)(dgst_raw[2 * i])) * 7) +
281 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
282 }
283 } else {
284 idx0 = seed % 6;
285 idx1 = 16;
286 idx2 = seed / 6;
287 retval[j++] = vowels[idx0];
288 retval[j++] = consonants[idx1];
289 retval[j++] = vowels[idx2];
290 }
291 }
292 retval[j++] = 'x';
293 retval[j++] = '\0';
294 return retval;
295 }
296
297 char *
298 key_fingerprint(Key *k, enum fp_type dgst_type, enum fp_rep dgst_rep)
299 {
300 char *retval = NULL;
301 u_char *dgst_raw;
302 u_int dgst_raw_len;
303
304 dgst_raw = key_fingerprint_raw(k, dgst_type, &dgst_raw_len);
305 if (!dgst_raw)
306 fatal("key_fingerprint: null from key_fingerprint_raw()");
307 switch (dgst_rep) {
308 case SSH_FP_HEX:
309 retval = key_fingerprint_hex(dgst_raw, dgst_raw_len);
310 break;
311 case SSH_FP_BUBBLEBABBLE:
312 retval = key_fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
313 break;
314 default:
315 fatal("key_fingerprint_ex: bad digest representation %d",
316 dgst_rep);
317 break;
318 }
319 memset(dgst_raw, 0, dgst_raw_len);
320 xfree(dgst_raw);
321 return retval;
322 }
323
324 /*
325 * Reads a multiple-precision integer in decimal from the buffer, and advances
326 * the pointer. The integer must already be initialized. This function is
327 * permitted to modify the buffer. This leaves *cpp to point just beyond the
328 * last processed (and maybe modified) character. Note that this may modify
329 * the buffer containing the number.
330 */
331 static int
332 read_bignum(char **cpp, BIGNUM * value)
333 {
334 char *cp = *cpp;
335 int old;
336
337 /* Skip any leading whitespace. */
338 for (; *cp == ' ' || *cp == '\t'; cp++)
339 ;
340
341 /* Check that it begins with a decimal digit. */
342 if (*cp < '0' || *cp > '9')
343 return 0;
344
345 /* Save starting position. */
346 *cpp = cp;
347
348 /* Move forward until all decimal digits skipped. */
349 for (; *cp >= '0' && *cp <= '9'; cp++)
350 ;
351
352 /* Save the old terminating character, and replace it by \0. */
353 old = *cp;
354 *cp = 0;
355
356 /* Parse the number. */
357 if (BN_dec2bn(&value, *cpp) == 0)
358 return 0;
359
360 /* Restore old terminating character. */
361 *cp = old;
362
363 /* Move beyond the number and return success. */
364 *cpp = cp;
365 return 1;
366 }
367
368 static int
369 write_bignum(FILE *f, BIGNUM *num)
370 {
371 char *buf = BN_bn2dec(num);
372 if (buf == NULL) {
373 error("write_bignum: BN_bn2dec() failed");
374 return 0;
375 }
376 fprintf(f, " %s", buf);
377 OPENSSL_free(buf);
378 return 1;
379 }
380
381 /* returns 1 ok, -1 error */
382 int
383 key_read(Key *ret, char **cpp)
384 {
385 Key *k;
386 int success = -1;
387 char *cp, *space;
388 int len, n, type;
389 u_int bits;
390 u_char *blob;
391
392 cp = *cpp;
393
394 switch (ret->type) {
395 case KEY_RSA1:
396 /* Get number of bits. */
397 if (*cp < '0' || *cp > '9')
398 return -1; /* Bad bit count... */
399 for (bits = 0; *cp >= '0' && *cp <= '9'; cp++)
400 bits = 10 * bits + *cp - '0';
401 if (bits == 0)
402 return -1;
403 *cpp = cp;
404 /* Get public exponent, public modulus. */
405 if (!read_bignum(cpp, ret->rsa->e))
406 return -1;
407 if (!read_bignum(cpp, ret->rsa->n))
408 return -1;
409 success = 1;
410 break;
411 case KEY_UNSPEC:
412 case KEY_RSA:
413 case KEY_DSA:
414 space = strchr(cp, ' ');
415 if (space == NULL) {
416 debug3("key_read: no space");
417 return -1;
418 }
419 *space = '\0';
420 type = key_type_from_name(cp);
421 *space = ' ';
422 if (type == KEY_UNSPEC) {
423 debug3("key_read: no key found");
424 return -1;
425 }
426 cp = space+1;
427 if (*cp == '\0') {
428 debug3("key_read: short string");
429 return -1;
430 }
431 if (ret->type == KEY_UNSPEC) {
432 ret->type = type;
433 } else if (ret->type != type) {
434 /* is a key, but different type */
435 debug3("key_read: type mismatch");
436 return -1;
437 }
438 len = 2*strlen(cp);
439 blob = xmalloc(len);
440 n = uudecode(cp, blob, len);
441 if (n < 0) {
442 error("key_read: uudecode %s failed", cp);
443 xfree(blob);
444 return -1;
445 }
446 k = key_from_blob(blob, n);
447 xfree(blob);
448 if (k == NULL) {
449 error("key_read: key_from_blob %s failed", cp);
450 return -1;
451 }
452 if (k->type != type) {
453 error("key_read: type mismatch: encoding error");
454 key_free(k);
455 return -1;
456 }
457 /*XXXX*/
458 if (ret->type == KEY_RSA) {
459 if (ret->rsa != NULL)
460 RSA_free(ret->rsa);
461 ret->rsa = k->rsa;
462 k->rsa = NULL;
463 success = 1;
464 #ifdef DEBUG_PK
465 RSA_print_fp(stderr, ret->rsa, 8);
466 #endif
467 } else {
468 if (ret->dsa != NULL)
469 DSA_free(ret->dsa);
470 ret->dsa = k->dsa;
471 k->dsa = NULL;
472 success = 1;
473 #ifdef DEBUG_PK
474 DSA_print_fp(stderr, ret->dsa, 8);
475 #endif
476 }
477 /*XXXX*/
478 key_free(k);
479 if (success != 1)
480 break;
481 /* advance cp: skip whitespace and data */
482 while (*cp == ' ' || *cp == '\t')
483 cp++;
484 while (*cp != '\0' && *cp != ' ' && *cp != '\t')
485 cp++;
486 *cpp = cp;
487 break;
488 default:
489 fatal("key_read: bad key type: %d", ret->type);
490 break;
491 }
492 return success;
493 }
494
495 int
496 key_write(const Key *key, FILE *f)
497 {
498 int n, success = 0;
499 u_int len, bits = 0;
500 u_char *blob;
501 char *uu;
502
503 if (key->type == KEY_RSA1 && key->rsa != NULL) {
504 /* size of modulus 'n' */
505 bits = BN_num_bits(key->rsa->n);
506 fprintf(f, "%u", bits);
507 if (write_bignum(f, key->rsa->e) &&
508 write_bignum(f, key->rsa->n)) {
509 success = 1;
510 } else {
511 error("key_write: failed for RSA key");
512 }
513 } else if ((key->type == KEY_DSA && key->dsa != NULL) ||
514 (key->type == KEY_RSA && key->rsa != NULL)) {
515 key_to_blob(key, &blob, &len);
516 uu = xmalloc(2*len);
517 n = uuencode(blob, len, uu, 2*len);
518 if (n > 0) {
519 fprintf(f, "%s %s", key_ssh_name(key), uu);
520 success = 1;
521 }
522 xfree(blob);
523 xfree(uu);
524 }
525 return success;
526 }
527
528 char *
529 key_type(Key *k)
530 {
531 switch (k->type) {
532 case KEY_RSA1:
533 return "RSA1";
534 break;
535 case KEY_RSA:
536 return "RSA";
537 break;
538 case KEY_DSA:
539 return "DSA";
540 break;
541 }
542 return "unknown";
543 }
544
545 char *
546 key_ssh_name(const Key *k)
547 {
548 switch (k->type) {
549 case KEY_RSA:
550 return "ssh-rsa";
551 break;
552 case KEY_DSA:
553 return "ssh-dss";
554 break;
555 }
556 return "ssh-unknown";
557 }
558
559 u_int
560 key_size(Key *k)
561 {
562 switch (k->type) {
563 case KEY_RSA1:
564 case KEY_RSA:
565 return BN_num_bits(k->rsa->n);
566 break;
567 case KEY_DSA:
568 return BN_num_bits(k->dsa->p);
569 break;
570 }
571 return 0;
572 }
573
574 static RSA *
575 rsa_generate_private_key(u_int bits)
576 {
577 RSA *private;
578 private = RSA_generate_key(bits, 35, NULL, NULL);
579 if (private == NULL)
580 fatal("rsa_generate_private_key: key generation failed.");
581 return private;
582 }
583
584 static DSA*
585 dsa_generate_private_key(u_int bits)
586 {
587 DSA *private = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
588 if (private == NULL)
589 fatal("dsa_generate_private_key: DSA_generate_parameters failed");
590 if (!DSA_generate_key(private))
591 fatal("dsa_generate_private_key: DSA_generate_key failed.");
592 if (private == NULL)
593 fatal("dsa_generate_private_key: NULL.");
594 return private;
595 }
596
597 Key *
598 key_generate(int type, u_int bits)
599 {
600 Key *k = key_new(KEY_UNSPEC);
601 switch (type) {
602 case KEY_DSA:
603 k->dsa = dsa_generate_private_key(bits);
604 break;
605 case KEY_RSA:
606 case KEY_RSA1:
607 k->rsa = rsa_generate_private_key(bits);
608 break;
609 default:
610 fatal("key_generate: unknown type %d", type);
611 }
612 k->type = type;
613 return k;
614 }
615
616 Key *
617 key_from_private(Key *k)
618 {
619 Key *n = NULL;
620 switch (k->type) {
621 case KEY_DSA:
622 n = key_new(k->type);
623 BN_copy(n->dsa->p, k->dsa->p);
624 BN_copy(n->dsa->q, k->dsa->q);
625 BN_copy(n->dsa->g, k->dsa->g);
626 BN_copy(n->dsa->pub_key, k->dsa->pub_key);
627 break;
628 case KEY_RSA:
629 case KEY_RSA1:
630 n = key_new(k->type);
631 BN_copy(n->rsa->n, k->rsa->n);
632 BN_copy(n->rsa->e, k->rsa->e);
633 break;
634 default:
635 fatal("key_from_private: unknown type %d", k->type);
636 break;
637 }
638 return n;
639 }
640
641 int
642 key_type_from_name(char *name)
643 {
644 if (strcmp(name, "rsa1") == 0) {
645 return KEY_RSA1;
646 } else if (strcmp(name, "rsa") == 0) {
647 return KEY_RSA;
648 } else if (strcmp(name, "dsa") == 0) {
649 return KEY_DSA;
650 } else if (strcmp(name, "ssh-rsa") == 0) {
651 return KEY_RSA;
652 } else if (strcmp(name, "ssh-dss") == 0) {
653 return KEY_DSA;
654 } else if (strcmp(name, "null") == 0){
655 return KEY_NULL;
656 }
657 debug2("key_type_from_name: unknown key type '%s'", name);
658 return KEY_UNSPEC;
659 }
660
661 int
662 key_names_valid2(const char *names)
663 {
664 char *s, *cp, *p;
665
666 if (names == NULL || strcmp(names, "") == 0)
667 return 0;
668 s = cp = xstrdup(names);
669 for ((p = strsep(&cp, ",")); p && *p != '\0';
670 (p = strsep(&cp, ","))) {
671 switch (key_type_from_name(p)) {
672 case KEY_RSA1:
673 case KEY_UNSPEC:
674 xfree(s);
675 return 0;
676 }
677 }
678 debug3("key names ok: [%s]", names);
679 xfree(s);
680 return 1;
681 }
682
683 Key *
684 key_from_blob(u_char *blob, int blen)
685 {
686 Buffer b;
687 char *ktype;
688 int rlen, type;
689 Key *key = NULL;
690
691 #ifdef DEBUG_PK
692 dump_base64(stderr, blob, blen);
693 #endif
694 buffer_init(&b);
695 buffer_append(&b, blob, blen);
696 if ((ktype = buffer_get_string_ret(&b, NULL)) == NULL) {
697 error("key_from_blob: can't read key type");
698 goto out;
699 }
700
701 type = key_type_from_name(ktype);
702
703 switch (type) {
704 case KEY_RSA:
705 key = key_new(type);
706 if (buffer_get_bignum2_ret(&b, key->rsa->e) == -1 ||
707 buffer_get_bignum2_ret(&b, key->rsa->n) == -1) {
708 error("key_from_blob: can't read rsa key");
709 key_free(key);
710 key = NULL;
711 goto out;
712 }
713 #ifdef DEBUG_PK
714 RSA_print_fp(stderr, key->rsa, 8);
715 #endif
716 break;
717 case KEY_DSA:
718 key = key_new(type);
719 if (buffer_get_bignum2_ret(&b, key->dsa->p) == -1 ||
720 buffer_get_bignum2_ret(&b, key->dsa->q) == -1 ||
721 buffer_get_bignum2_ret(&b, key->dsa->g) == -1 ||
722 buffer_get_bignum2_ret(&b, key->dsa->pub_key) == -1) {
723 error("key_from_blob: can't read dsa key");
724 key_free(key);
725 key = NULL;
726 goto out;
727 }
728 #ifdef DEBUG_PK
729 DSA_print_fp(stderr, key->dsa, 8);
730 #endif
731 break;
732 case KEY_UNSPEC:
733 key = key_new(type);
734 break;
735 default:
736 error("key_from_blob: cannot handle type %s", ktype);
737 goto out;
738 }
739 rlen = buffer_len(&b);
740 if (key != NULL && rlen != 0)
741 error("key_from_blob: remaining bytes in key blob %d", rlen);
742 out:
743 if (ktype != NULL)
744 xfree(ktype);
745 buffer_free(&b);
746 return key;
747 }
748
749 int
750 key_to_blob(const Key *key, u_char **blobp, u_int *lenp)
751 {
752 Buffer b;
753 int len;
754
755 if (key == NULL) {
756 error("key_to_blob: key == NULL");
757 return 0;
758 }
759 buffer_init(&b);
760 switch (key->type) {
761 case KEY_DSA:
762 buffer_put_cstring(&b, key_ssh_name(key));
763 buffer_put_bignum2(&b, key->dsa->p);
764 buffer_put_bignum2(&b, key->dsa->q);
765 buffer_put_bignum2(&b, key->dsa->g);
766 buffer_put_bignum2(&b, key->dsa->pub_key);
767 break;
768 case KEY_RSA:
769 buffer_put_cstring(&b, key_ssh_name(key));
770 buffer_put_bignum2(&b, key->rsa->e);
771 buffer_put_bignum2(&b, key->rsa->n);
772 break;
773 default:
774 error("key_to_blob: unsupported key type %d", key->type);
775 buffer_free(&b);
776 return 0;
777 }
778 len = buffer_len(&b);
779 if (lenp != NULL)
780 *lenp = len;
781 if (blobp != NULL) {
782 *blobp = xmalloc(len);
783 memcpy(*blobp, buffer_ptr(&b), len);
784 }
785 memset(buffer_ptr(&b), 0, len);
786 buffer_free(&b);
787 return len;
788 }
789
790 int
791 key_sign(
792 Key *key,
793 u_char **sigp, u_int *lenp,
794 u_char *data, u_int datalen)
795 {
796 switch (key->type) {
797 case KEY_DSA:
798 return ssh_dss_sign(key, sigp, lenp, data, datalen);
799 break;
800 case KEY_RSA:
801 return ssh_rsa_sign(key, sigp, lenp, data, datalen);
802 break;
803 default:
804 error("key_sign: illegal key type %d", key->type);
805 return -1;
806 break;
807 }
808 }
809
810 /*
811 * key_verify returns 1 for a correct signature, 0 for an incorrect signature
812 * and -1 on error.
813 */
814 int
815 key_verify(
816 Key *key,
817 u_char *signature, u_int signaturelen,
818 u_char *data, u_int datalen)
819 {
820 if (signaturelen == 0)
821 return -1;
822
823 switch (key->type) {
824 case KEY_DSA:
825 return ssh_dss_verify(key, signature, signaturelen, data, datalen);
826 break;
827 case KEY_RSA:
828 return ssh_rsa_verify(key, signature, signaturelen, data, datalen);
829 break;
830 default:
831 error("key_verify: illegal key type %d", key->type);
832 return -1;
833 break;
834 }
835 }
836
837 /* Converts a private to a public key */
838 Key *
839 key_demote(Key *k)
840 {
841 Key *pk;
842
843 pk = xmalloc(sizeof(*pk));
844 pk->type = k->type;
845 pk->flags = k->flags;
846 pk->dsa = NULL;
847 pk->rsa = NULL;
848
849 switch (k->type) {
850 case KEY_RSA1:
851 case KEY_RSA:
852 if ((pk->rsa = RSA_new()) == NULL)
853 fatal("key_demote: RSA_new failed");
854 if ((pk->rsa->e = BN_dup(k->rsa->e)) == NULL)
855 fatal("key_demote: BN_dup failed");
856 if ((pk->rsa->n = BN_dup(k->rsa->n)) == NULL)
857 fatal("key_demote: BN_dup failed");
858 break;
859 case KEY_DSA:
860 if ((pk->dsa = DSA_new()) == NULL)
861 fatal("key_demote: DSA_new failed");
862 if ((pk->dsa->p = BN_dup(k->dsa->p)) == NULL)
863 fatal("key_demote: BN_dup failed");
864 if ((pk->dsa->q = BN_dup(k->dsa->q)) == NULL)
865 fatal("key_demote: BN_dup failed");
866 if ((pk->dsa->g = BN_dup(k->dsa->g)) == NULL)
867 fatal("key_demote: BN_dup failed");
868 if ((pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL)
869 fatal("key_demote: BN_dup failed");
870 break;
871 default:
872 fatal("key_free: bad key type %d", k->type);
873 break;
874 }
875
876 return (pk);
877 }