1 /* $OpenBSD: sshkey.c,v 1.142 2024/01/11 01:45:36 djm Exp $ */
2 /*
3 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
4 * Copyright (c) 2008 Alexander von Gernler. All rights reserved.
5 * Copyright (c) 2010,2011 Damien Miller. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include <sys/types.h>
29 #include <netinet/in.h>
30
31 #ifdef WITH_OPENSSL
32 #include <openssl/evp.h>
33 #include <openssl/err.h>
34 #include <openssl/pem.h>
35 #endif
36
37 #include "crypto_api.h"
38
39 #include <errno.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <util.h>
44 #include <limits.h>
45 #include <resolv.h>
46
47 #include "ssh2.h"
48 #include "ssherr.h"
49 #include "misc.h"
50 #include "sshbuf.h"
51 #include "cipher.h"
52 #include "digest.h"
53 #define SSHKEY_INTERNAL
54 #include "sshkey.h"
55 #include "match.h"
56 #include "ssh-sk.h"
57
58 #ifdef WITH_XMSS
59 #include "sshkey-xmss.h"
60 #include "xmss_fast.h"
61 #endif
62
63 /* openssh private key file format */
64 #define MARK_BEGIN "-----BEGIN OPENSSH PRIVATE KEY-----\n"
65 #define MARK_END "-----END OPENSSH PRIVATE KEY-----\n"
66 #define MARK_BEGIN_LEN (sizeof(MARK_BEGIN) - 1)
67 #define MARK_END_LEN (sizeof(MARK_END) - 1)
68 #define KDFNAME "bcrypt"
69 #define AUTH_MAGIC "openssh-key-v1"
70 #define SALT_LEN 16
71 #define DEFAULT_CIPHERNAME "aes256-ctr"
72 #define DEFAULT_ROUNDS 24
73
74 /* Version identification string for SSH v1 identity files. */
75 #define LEGACY_BEGIN "SSH PRIVATE KEY FILE FORMAT 1.1\n"
76
77 /*
78 * Constants relating to "shielding" support; protection of keys expected
79 * to remain in memory for long durations
80 */
81 #define SSHKEY_SHIELD_PREKEY_LEN (16 * 1024)
82 #define SSHKEY_SHIELD_CIPHER "aes256-ctr" /* XXX want AES-EME* */
83 #define SSHKEY_SHIELD_PREKEY_HASH SSH_DIGEST_SHA512
84
85 int sshkey_private_serialize_opt(struct sshkey *key,
86 struct sshbuf *buf, enum sshkey_serialize_rep);
87 static int sshkey_from_blob_internal(struct sshbuf *buf,
88 struct sshkey **keyp, int allow_cert);
89
90 /* Supported key types */
91 extern const struct sshkey_impl sshkey_ed25519_impl;
92 extern const struct sshkey_impl sshkey_ed25519_cert_impl;
93 extern const struct sshkey_impl sshkey_ed25519_sk_impl;
94 extern const struct sshkey_impl sshkey_ed25519_sk_cert_impl;
95 #ifdef WITH_OPENSSL
96 extern const struct sshkey_impl sshkey_ecdsa_sk_impl;
97 extern const struct sshkey_impl sshkey_ecdsa_sk_cert_impl;
98 extern const struct sshkey_impl sshkey_ecdsa_sk_webauthn_impl;
99 extern const struct sshkey_impl sshkey_ecdsa_nistp256_impl;
100 extern const struct sshkey_impl sshkey_ecdsa_nistp256_cert_impl;
101 extern const struct sshkey_impl sshkey_ecdsa_nistp384_impl;
102 extern const struct sshkey_impl sshkey_ecdsa_nistp384_cert_impl;
103 extern const struct sshkey_impl sshkey_ecdsa_nistp521_impl;
104 extern const struct sshkey_impl sshkey_ecdsa_nistp521_cert_impl;
105 extern const struct sshkey_impl sshkey_rsa_impl;
106 extern const struct sshkey_impl sshkey_rsa_cert_impl;
107 extern const struct sshkey_impl sshkey_rsa_sha256_impl;
108 extern const struct sshkey_impl sshkey_rsa_sha256_cert_impl;
109 extern const struct sshkey_impl sshkey_rsa_sha512_impl;
110 extern const struct sshkey_impl sshkey_rsa_sha512_cert_impl;
111 # ifdef WITH_DSA
112 extern const struct sshkey_impl sshkey_dss_impl;
113 extern const struct sshkey_impl sshkey_dsa_cert_impl;
114 # endif
115 #endif /* WITH_OPENSSL */
116 #ifdef WITH_XMSS
117 extern const struct sshkey_impl sshkey_xmss_impl;
118 extern const struct sshkey_impl sshkey_xmss_cert_impl;
119 #endif
120
121 const struct sshkey_impl * const keyimpls[] = {
122 &sshkey_ed25519_impl,
123 &sshkey_ed25519_cert_impl,
124 &sshkey_ed25519_sk_impl,
125 &sshkey_ed25519_sk_cert_impl,
126 #ifdef WITH_OPENSSL
127 &sshkey_ecdsa_nistp256_impl,
128 &sshkey_ecdsa_nistp256_cert_impl,
129 &sshkey_ecdsa_nistp384_impl,
130 &sshkey_ecdsa_nistp384_cert_impl,
131 &sshkey_ecdsa_nistp521_impl,
132 &sshkey_ecdsa_nistp521_cert_impl,
133 &sshkey_ecdsa_sk_impl,
134 &sshkey_ecdsa_sk_cert_impl,
135 &sshkey_ecdsa_sk_webauthn_impl,
136 # ifdef WITH_DSA
137 &sshkey_dss_impl,
138 &sshkey_dsa_cert_impl,
139 # endif
140 &sshkey_rsa_impl,
141 &sshkey_rsa_cert_impl,
142 &sshkey_rsa_sha256_impl,
143 &sshkey_rsa_sha256_cert_impl,
144 &sshkey_rsa_sha512_impl,
145 &sshkey_rsa_sha512_cert_impl,
146 #endif /* WITH_OPENSSL */
147 #ifdef WITH_XMSS
148 &sshkey_xmss_impl,
149 &sshkey_xmss_cert_impl,
150 #endif
151 NULL
152 };
153
154 static const struct sshkey_impl *
sshkey_impl_from_type(int type)155 sshkey_impl_from_type(int type)
156 {
157 int i;
158
159 for (i = 0; keyimpls[i] != NULL; i++) {
160 if (keyimpls[i]->type == type)
161 return keyimpls[i];
162 }
163 return NULL;
164 }
165
166 static const struct sshkey_impl *
sshkey_impl_from_type_nid(int type,int nid)167 sshkey_impl_from_type_nid(int type, int nid)
168 {
169 int i;
170
171 for (i = 0; keyimpls[i] != NULL; i++) {
172 if (keyimpls[i]->type == type &&
173 (keyimpls[i]->nid == 0 || keyimpls[i]->nid == nid))
174 return keyimpls[i];
175 }
176 return NULL;
177 }
178
179 static const struct sshkey_impl *
sshkey_impl_from_key(const struct sshkey * k)180 sshkey_impl_from_key(const struct sshkey *k)
181 {
182 if (k == NULL)
183 return NULL;
184 return sshkey_impl_from_type_nid(k->type, k->ecdsa_nid);
185 }
186
187 const char *
sshkey_type(const struct sshkey * k)188 sshkey_type(const struct sshkey *k)
189 {
190 const struct sshkey_impl *impl;
191
192 if ((impl = sshkey_impl_from_key(k)) == NULL)
193 return "unknown";
194 return impl->shortname;
195 }
196
197 static const char *
sshkey_ssh_name_from_type_nid(int type,int nid)198 sshkey_ssh_name_from_type_nid(int type, int nid)
199 {
200 const struct sshkey_impl *impl;
201
202 if ((impl = sshkey_impl_from_type_nid(type, nid)) == NULL)
203 return "ssh-unknown";
204 return impl->name;
205 }
206
207 int
sshkey_type_is_cert(int type)208 sshkey_type_is_cert(int type)
209 {
210 const struct sshkey_impl *impl;
211
212 if ((impl = sshkey_impl_from_type(type)) == NULL)
213 return 0;
214 return impl->cert;
215 }
216
217 const char *
sshkey_ssh_name(const struct sshkey * k)218 sshkey_ssh_name(const struct sshkey *k)
219 {
220 return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
221 }
222
223 const char *
sshkey_ssh_name_plain(const struct sshkey * k)224 sshkey_ssh_name_plain(const struct sshkey *k)
225 {
226 return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type),
227 k->ecdsa_nid);
228 }
229
230 int
sshkey_type_from_name(const char * name)231 sshkey_type_from_name(const char *name)
232 {
233 int i;
234 const struct sshkey_impl *impl;
235
236 for (i = 0; keyimpls[i] != NULL; i++) {
237 impl = keyimpls[i];
238 /* Only allow shortname matches for plain key types */
239 if ((impl->name != NULL && strcmp(name, impl->name) == 0) ||
240 (!impl->cert && strcasecmp(impl->shortname, name) == 0))
241 return impl->type;
242 }
243 return KEY_UNSPEC;
244 }
245
246 static int
key_type_is_ecdsa_variant(int type)247 key_type_is_ecdsa_variant(int type)
248 {
249 switch (type) {
250 case KEY_ECDSA:
251 case KEY_ECDSA_CERT:
252 case KEY_ECDSA_SK:
253 case KEY_ECDSA_SK_CERT:
254 return 1;
255 }
256 return 0;
257 }
258
259 int
sshkey_ecdsa_nid_from_name(const char * name)260 sshkey_ecdsa_nid_from_name(const char *name)
261 {
262 int i;
263
264 for (i = 0; keyimpls[i] != NULL; i++) {
265 if (!key_type_is_ecdsa_variant(keyimpls[i]->type))
266 continue;
267 if (keyimpls[i]->name != NULL &&
268 strcmp(name, keyimpls[i]->name) == 0)
269 return keyimpls[i]->nid;
270 }
271 return -1;
272 }
273
274 int
sshkey_match_keyname_to_sigalgs(const char * keyname,const char * sigalgs)275 sshkey_match_keyname_to_sigalgs(const char *keyname, const char *sigalgs)
276 {
277 int ktype;
278
279 if (sigalgs == NULL || *sigalgs == '\0' ||
280 (ktype = sshkey_type_from_name(keyname)) == KEY_UNSPEC)
281 return 0;
282 else if (ktype == KEY_RSA) {
283 return match_pattern_list("ssh-rsa", sigalgs, 0) == 1 ||
284 match_pattern_list("rsa-sha2-256", sigalgs, 0) == 1 ||
285 match_pattern_list("rsa-sha2-512", sigalgs, 0) == 1;
286 } else if (ktype == KEY_RSA_CERT) {
287 return match_pattern_list("ssh-rsa-cert-v01@openssh.com",
288 sigalgs, 0) == 1 ||
289 match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
290 sigalgs, 0) == 1 ||
291 match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
292 sigalgs, 0) == 1;
293 } else
294 return match_pattern_list(keyname, sigalgs, 0) == 1;
295 }
296
297 char *
sshkey_alg_list(int certs_only,int plain_only,int include_sigonly,char sep)298 sshkey_alg_list(int certs_only, int plain_only, int include_sigonly, char sep)
299 {
300 char *tmp, *ret = NULL;
301 size_t i, nlen, rlen = 0;
302 const struct sshkey_impl *impl;
303
304 for (i = 0; keyimpls[i] != NULL; i++) {
305 impl = keyimpls[i];
306 if (impl->name == NULL)
307 continue;
308 if (!include_sigonly && impl->sigonly)
309 continue;
310 if ((certs_only && !impl->cert) || (plain_only && impl->cert))
311 continue;
312 if (ret != NULL)
313 ret[rlen++] = sep;
314 nlen = strlen(impl->name);
315 if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
316 free(ret);
317 return NULL;
318 }
319 ret = tmp;
320 memcpy(ret + rlen, impl->name, nlen + 1);
321 rlen += nlen;
322 }
323 return ret;
324 }
325
326 int
sshkey_names_valid2(const char * names,int allow_wildcard,int plain_only)327 sshkey_names_valid2(const char *names, int allow_wildcard, int plain_only)
328 {
329 char *s, *cp, *p;
330 const struct sshkey_impl *impl;
331 int i, type;
332
333 if (names == NULL || strcmp(names, "") == 0)
334 return 0;
335 if ((s = cp = strdup(names)) == NULL)
336 return 0;
337 for ((p = strsep(&cp, ",")); p && *p != '\0';
338 (p = strsep(&cp, ","))) {
339 type = sshkey_type_from_name(p);
340 if (type == KEY_UNSPEC) {
341 if (allow_wildcard) {
342 /*
343 * Try matching key types against the string.
344 * If any has a positive or negative match then
345 * the component is accepted.
346 */
347 impl = NULL;
348 for (i = 0; keyimpls[i] != NULL; i++) {
349 if (match_pattern_list(
350 keyimpls[i]->name, p, 0) != 0) {
351 impl = keyimpls[i];
352 break;
353 }
354 }
355 if (impl != NULL)
356 continue;
357 }
358 free(s);
359 return 0;
360 } else if (plain_only && sshkey_type_is_cert(type)) {
361 free(s);
362 return 0;
363 }
364 }
365 free(s);
366 return 1;
367 }
368
369 u_int
sshkey_size(const struct sshkey * k)370 sshkey_size(const struct sshkey *k)
371 {
372 const struct sshkey_impl *impl;
373
374 if ((impl = sshkey_impl_from_key(k)) == NULL)
375 return 0;
376 if (impl->funcs->size != NULL)
377 return impl->funcs->size(k);
378 return impl->keybits;
379 }
380
381 static int
sshkey_type_is_valid_ca(int type)382 sshkey_type_is_valid_ca(int type)
383 {
384 const struct sshkey_impl *impl;
385
386 if ((impl = sshkey_impl_from_type(type)) == NULL)
387 return 0;
388 /* All non-certificate types may act as CAs */
389 return !impl->cert;
390 }
391
392 int
sshkey_is_cert(const struct sshkey * k)393 sshkey_is_cert(const struct sshkey *k)
394 {
395 if (k == NULL)
396 return 0;
397 return sshkey_type_is_cert(k->type);
398 }
399
400 int
sshkey_is_sk(const struct sshkey * k)401 sshkey_is_sk(const struct sshkey *k)
402 {
403 if (k == NULL)
404 return 0;
405 switch (sshkey_type_plain(k->type)) {
406 case KEY_ECDSA_SK:
407 case KEY_ED25519_SK:
408 return 1;
409 default:
410 return 0;
411 }
412 }
413
414 /* Return the cert-less equivalent to a certified key type */
415 int
sshkey_type_plain(int type)416 sshkey_type_plain(int type)
417 {
418 switch (type) {
419 case KEY_RSA_CERT:
420 return KEY_RSA;
421 case KEY_DSA_CERT:
422 return KEY_DSA;
423 case KEY_ECDSA_CERT:
424 return KEY_ECDSA;
425 case KEY_ECDSA_SK_CERT:
426 return KEY_ECDSA_SK;
427 case KEY_ED25519_CERT:
428 return KEY_ED25519;
429 case KEY_ED25519_SK_CERT:
430 return KEY_ED25519_SK;
431 case KEY_XMSS_CERT:
432 return KEY_XMSS;
433 default:
434 return type;
435 }
436 }
437
438 /* Return the cert equivalent to a plain key type */
439 static int
sshkey_type_certified(int type)440 sshkey_type_certified(int type)
441 {
442 switch (type) {
443 case KEY_RSA:
444 return KEY_RSA_CERT;
445 case KEY_DSA:
446 return KEY_DSA_CERT;
447 case KEY_ECDSA:
448 return KEY_ECDSA_CERT;
449 case KEY_ECDSA_SK:
450 return KEY_ECDSA_SK_CERT;
451 case KEY_ED25519:
452 return KEY_ED25519_CERT;
453 case KEY_ED25519_SK:
454 return KEY_ED25519_SK_CERT;
455 case KEY_XMSS:
456 return KEY_XMSS_CERT;
457 default:
458 return -1;
459 }
460 }
461
462 #ifdef WITH_OPENSSL
463 /* XXX: these are really begging for a table-driven approach */
464 int
sshkey_curve_name_to_nid(const char * name)465 sshkey_curve_name_to_nid(const char *name)
466 {
467 if (strcmp(name, "nistp256") == 0)
468 return NID_X9_62_prime256v1;
469 else if (strcmp(name, "nistp384") == 0)
470 return NID_secp384r1;
471 else if (strcmp(name, "nistp521") == 0)
472 return NID_secp521r1;
473 else
474 return -1;
475 }
476
477 u_int
sshkey_curve_nid_to_bits(int nid)478 sshkey_curve_nid_to_bits(int nid)
479 {
480 switch (nid) {
481 case NID_X9_62_prime256v1:
482 return 256;
483 case NID_secp384r1:
484 return 384;
485 case NID_secp521r1:
486 return 521;
487 default:
488 return 0;
489 }
490 }
491
492 int
sshkey_ecdsa_bits_to_nid(int bits)493 sshkey_ecdsa_bits_to_nid(int bits)
494 {
495 switch (bits) {
496 case 256:
497 return NID_X9_62_prime256v1;
498 case 384:
499 return NID_secp384r1;
500 case 521:
501 return NID_secp521r1;
502 default:
503 return -1;
504 }
505 }
506
507 const char *
sshkey_curve_nid_to_name(int nid)508 sshkey_curve_nid_to_name(int nid)
509 {
510 switch (nid) {
511 case NID_X9_62_prime256v1:
512 return "nistp256";
513 case NID_secp384r1:
514 return "nistp384";
515 case NID_secp521r1:
516 return "nistp521";
517 default:
518 return NULL;
519 }
520 }
521
522 int
sshkey_ec_nid_to_hash_alg(int nid)523 sshkey_ec_nid_to_hash_alg(int nid)
524 {
525 int kbits = sshkey_curve_nid_to_bits(nid);
526
527 if (kbits <= 0)
528 return -1;
529
530 /* RFC5656 section 6.2.1 */
531 if (kbits <= 256)
532 return SSH_DIGEST_SHA256;
533 else if (kbits <= 384)
534 return SSH_DIGEST_SHA384;
535 else
536 return SSH_DIGEST_SHA512;
537 }
538 #endif /* WITH_OPENSSL */
539
540 static void
cert_free(struct sshkey_cert * cert)541 cert_free(struct sshkey_cert *cert)
542 {
543 u_int i;
544
545 if (cert == NULL)
546 return;
547 sshbuf_free(cert->certblob);
548 sshbuf_free(cert->critical);
549 sshbuf_free(cert->extensions);
550 free(cert->key_id);
551 for (i = 0; i < cert->nprincipals; i++)
552 free(cert->principals[i]);
553 free(cert->principals);
554 sshkey_free(cert->signature_key);
555 free(cert->signature_type);
556 freezero(cert, sizeof(*cert));
557 }
558
559 static struct sshkey_cert *
cert_new(void)560 cert_new(void)
561 {
562 struct sshkey_cert *cert;
563
564 if ((cert = calloc(1, sizeof(*cert))) == NULL)
565 return NULL;
566 if ((cert->certblob = sshbuf_new()) == NULL ||
567 (cert->critical = sshbuf_new()) == NULL ||
568 (cert->extensions = sshbuf_new()) == NULL) {
569 cert_free(cert);
570 return NULL;
571 }
572 cert->key_id = NULL;
573 cert->principals = NULL;
574 cert->signature_key = NULL;
575 cert->signature_type = NULL;
576 return cert;
577 }
578
579 struct sshkey *
sshkey_new(int type)580 sshkey_new(int type)
581 {
582 struct sshkey *k;
583 const struct sshkey_impl *impl = NULL;
584
585 if (type != KEY_UNSPEC &&
586 (impl = sshkey_impl_from_type(type)) == NULL)
587 return NULL;
588
589 /* All non-certificate types may act as CAs */
590 if ((k = calloc(1, sizeof(*k))) == NULL)
591 return NULL;
592 k->type = type;
593 k->ecdsa_nid = -1;
594 if (impl != NULL && impl->funcs->alloc != NULL) {
595 if (impl->funcs->alloc(k) != 0) {
596 free(k);
597 return NULL;
598 }
599 }
600 if (sshkey_is_cert(k)) {
601 if ((k->cert = cert_new()) == NULL) {
602 sshkey_free(k);
603 return NULL;
604 }
605 }
606
607 return k;
608 }
609
610 /* Frees common FIDO fields */
611 void
sshkey_sk_cleanup(struct sshkey * k)612 sshkey_sk_cleanup(struct sshkey *k)
613 {
614 free(k->sk_application);
615 sshbuf_free(k->sk_key_handle);
616 sshbuf_free(k->sk_reserved);
617 k->sk_application = NULL;
618 k->sk_key_handle = k->sk_reserved = NULL;
619 }
620
621 static void
sshkey_free_contents(struct sshkey * k)622 sshkey_free_contents(struct sshkey *k)
623 {
624 const struct sshkey_impl *impl;
625
626 if (k == NULL)
627 return;
628 if ((impl = sshkey_impl_from_type(k->type)) != NULL &&
629 impl->funcs->cleanup != NULL)
630 impl->funcs->cleanup(k);
631 if (sshkey_is_cert(k))
632 cert_free(k->cert);
633 freezero(k->shielded_private, k->shielded_len);
634 freezero(k->shield_prekey, k->shield_prekey_len);
635 }
636
637 void
sshkey_free(struct sshkey * k)638 sshkey_free(struct sshkey *k)
639 {
640 sshkey_free_contents(k);
641 freezero(k, sizeof(*k));
642 }
643
644 static int
cert_compare(struct sshkey_cert * a,struct sshkey_cert * b)645 cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
646 {
647 if (a == NULL && b == NULL)
648 return 1;
649 if (a == NULL || b == NULL)
650 return 0;
651 if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob))
652 return 0;
653 if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob),
654 sshbuf_len(a->certblob)) != 0)
655 return 0;
656 return 1;
657 }
658
659 /* Compares FIDO-specific pubkey fields only */
660 int
sshkey_sk_fields_equal(const struct sshkey * a,const struct sshkey * b)661 sshkey_sk_fields_equal(const struct sshkey *a, const struct sshkey *b)
662 {
663 if (a->sk_application == NULL || b->sk_application == NULL)
664 return 0;
665 if (strcmp(a->sk_application, b->sk_application) != 0)
666 return 0;
667 return 1;
668 }
669
670 /*
671 * Compare public portions of key only, allowing comparisons between
672 * certificates and plain keys too.
673 */
674 int
sshkey_equal_public(const struct sshkey * a,const struct sshkey * b)675 sshkey_equal_public(const struct sshkey *a, const struct sshkey *b)
676 {
677 const struct sshkey_impl *impl;
678
679 if (a == NULL || b == NULL ||
680 sshkey_type_plain(a->type) != sshkey_type_plain(b->type))
681 return 0;
682 if ((impl = sshkey_impl_from_type(a->type)) == NULL)
683 return 0;
684 return impl->funcs->equal(a, b);
685 }
686
687 int
sshkey_equal(const struct sshkey * a,const struct sshkey * b)688 sshkey_equal(const struct sshkey *a, const struct sshkey *b)
689 {
690 if (a == NULL || b == NULL || a->type != b->type)
691 return 0;
692 if (sshkey_is_cert(a)) {
693 if (!cert_compare(a->cert, b->cert))
694 return 0;
695 }
696 return sshkey_equal_public(a, b);
697 }
698
699
700 /* Serialise common FIDO key parts */
701 int
sshkey_serialize_sk(const struct sshkey * key,struct sshbuf * b)702 sshkey_serialize_sk(const struct sshkey *key, struct sshbuf *b)
703 {
704 int r;
705
706 if ((r = sshbuf_put_cstring(b, key->sk_application)) != 0)
707 return r;
708
709 return 0;
710 }
711
712 static int
to_blob_buf(const struct sshkey * key,struct sshbuf * b,int force_plain,enum sshkey_serialize_rep opts)713 to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain,
714 enum sshkey_serialize_rep opts)
715 {
716 int type, ret = SSH_ERR_INTERNAL_ERROR;
717 const char *typename;
718 const struct sshkey_impl *impl;
719
720 if (key == NULL)
721 return SSH_ERR_INVALID_ARGUMENT;
722
723 type = force_plain ? sshkey_type_plain(key->type) : key->type;
724
725 if (sshkey_type_is_cert(type)) {
726 if (key->cert == NULL)
727 return SSH_ERR_EXPECTED_CERT;
728 if (sshbuf_len(key->cert->certblob) == 0)
729 return SSH_ERR_KEY_LACKS_CERTBLOB;
730 /* Use the existing blob */
731 if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0)
732 return ret;
733 return 0;
734 }
735 if ((impl = sshkey_impl_from_type(type)) == NULL)
736 return SSH_ERR_KEY_TYPE_UNKNOWN;
737
738 typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid);
739 if ((ret = sshbuf_put_cstring(b, typename)) != 0)
740 return ret;
741 return impl->funcs->serialize_public(key, b, opts);
742 }
743
744 int
sshkey_putb(const struct sshkey * key,struct sshbuf * b)745 sshkey_putb(const struct sshkey *key, struct sshbuf *b)
746 {
747 return to_blob_buf(key, b, 0, SSHKEY_SERIALIZE_DEFAULT);
748 }
749
750 int
sshkey_puts_opts(const struct sshkey * key,struct sshbuf * b,enum sshkey_serialize_rep opts)751 sshkey_puts_opts(const struct sshkey *key, struct sshbuf *b,
752 enum sshkey_serialize_rep opts)
753 {
754 struct sshbuf *tmp;
755 int r;
756
757 if ((tmp = sshbuf_new()) == NULL)
758 return SSH_ERR_ALLOC_FAIL;
759 r = to_blob_buf(key, tmp, 0, opts);
760 if (r == 0)
761 r = sshbuf_put_stringb(b, tmp);
762 sshbuf_free(tmp);
763 return r;
764 }
765
766 int
sshkey_puts(const struct sshkey * key,struct sshbuf * b)767 sshkey_puts(const struct sshkey *key, struct sshbuf *b)
768 {
769 return sshkey_puts_opts(key, b, SSHKEY_SERIALIZE_DEFAULT);
770 }
771
772 int
sshkey_putb_plain(const struct sshkey * key,struct sshbuf * b)773 sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b)
774 {
775 return to_blob_buf(key, b, 1, SSHKEY_SERIALIZE_DEFAULT);
776 }
777
778 static int
to_blob(const struct sshkey * key,u_char ** blobp,size_t * lenp,int force_plain,enum sshkey_serialize_rep opts)779 to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain,
780 enum sshkey_serialize_rep opts)
781 {
782 int ret = SSH_ERR_INTERNAL_ERROR;
783 size_t len;
784 struct sshbuf *b = NULL;
785
786 if (lenp != NULL)
787 *lenp = 0;
788 if (blobp != NULL)
789 *blobp = NULL;
790 if ((b = sshbuf_new()) == NULL)
791 return SSH_ERR_ALLOC_FAIL;
792 if ((ret = to_blob_buf(key, b, force_plain, opts)) != 0)
793 goto out;
794 len = sshbuf_len(b);
795 if (lenp != NULL)
796 *lenp = len;
797 if (blobp != NULL) {
798 if ((*blobp = malloc(len)) == NULL) {
799 ret = SSH_ERR_ALLOC_FAIL;
800 goto out;
801 }
802 memcpy(*blobp, sshbuf_ptr(b), len);
803 }
804 ret = 0;
805 out:
806 sshbuf_free(b);
807 return ret;
808 }
809
810 int
sshkey_to_blob(const struct sshkey * key,u_char ** blobp,size_t * lenp)811 sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
812 {
813 return to_blob(key, blobp, lenp, 0, SSHKEY_SERIALIZE_DEFAULT);
814 }
815
816 int
sshkey_plain_to_blob(const struct sshkey * key,u_char ** blobp,size_t * lenp)817 sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
818 {
819 return to_blob(key, blobp, lenp, 1, SSHKEY_SERIALIZE_DEFAULT);
820 }
821
822 int
sshkey_fingerprint_raw(const struct sshkey * k,int dgst_alg,u_char ** retp,size_t * lenp)823 sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg,
824 u_char **retp, size_t *lenp)
825 {
826 u_char *blob = NULL, *ret = NULL;
827 size_t blob_len = 0;
828 int r = SSH_ERR_INTERNAL_ERROR;
829
830 if (retp != NULL)
831 *retp = NULL;
832 if (lenp != NULL)
833 *lenp = 0;
834 if (ssh_digest_bytes(dgst_alg) == 0) {
835 r = SSH_ERR_INVALID_ARGUMENT;
836 goto out;
837 }
838 if ((r = to_blob(k, &blob, &blob_len, 1, SSHKEY_SERIALIZE_DEFAULT))
839 != 0)
840 goto out;
841 if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) {
842 r = SSH_ERR_ALLOC_FAIL;
843 goto out;
844 }
845 if ((r = ssh_digest_memory(dgst_alg, blob, blob_len,
846 ret, SSH_DIGEST_MAX_LENGTH)) != 0)
847 goto out;
848 /* success */
849 if (retp != NULL) {
850 *retp = ret;
851 ret = NULL;
852 }
853 if (lenp != NULL)
854 *lenp = ssh_digest_bytes(dgst_alg);
855 r = 0;
856 out:
857 free(ret);
858 if (blob != NULL)
859 freezero(blob, blob_len);
860 return r;
861 }
862
863 static char *
fingerprint_b64(const char * alg,u_char * dgst_raw,size_t dgst_raw_len)864 fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
865 {
866 char *ret;
867 size_t plen = strlen(alg) + 1;
868 size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1;
869
870 if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL)
871 return NULL;
872 strlcpy(ret, alg, rlen);
873 strlcat(ret, ":", rlen);
874 if (dgst_raw_len == 0)
875 return ret;
876 if (b64_ntop(dgst_raw, dgst_raw_len, ret + plen, rlen - plen) == -1) {
877 freezero(ret, rlen);
878 return NULL;
879 }
880 /* Trim padding characters from end */
881 ret[strcspn(ret, "=")] = '\0';
882 return ret;
883 }
884
885 static char *
fingerprint_hex(const char * alg,u_char * dgst_raw,size_t dgst_raw_len)886 fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
887 {
888 char *retval, hex[5];
889 size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2;
890
891 if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL)
892 return NULL;
893 strlcpy(retval, alg, rlen);
894 strlcat(retval, ":", rlen);
895 for (i = 0; i < dgst_raw_len; i++) {
896 snprintf(hex, sizeof(hex), "%s%02x",
897 i > 0 ? ":" : "", dgst_raw[i]);
898 strlcat(retval, hex, rlen);
899 }
900 return retval;
901 }
902
903 static char *
fingerprint_bubblebabble(u_char * dgst_raw,size_t dgst_raw_len)904 fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len)
905 {
906 char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
907 char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
908 'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
909 u_int i, j = 0, rounds, seed = 1;
910 char *retval;
911
912 rounds = (dgst_raw_len / 2) + 1;
913 if ((retval = calloc(rounds, 6)) == NULL)
914 return NULL;
915 retval[j++] = 'x';
916 for (i = 0; i < rounds; i++) {
917 u_int idx0, idx1, idx2, idx3, idx4;
918 if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
919 idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
920 seed) % 6;
921 idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
922 idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
923 (seed / 6)) % 6;
924 retval[j++] = vowels[idx0];
925 retval[j++] = consonants[idx1];
926 retval[j++] = vowels[idx2];
927 if ((i + 1) < rounds) {
928 idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
929 idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
930 retval[j++] = consonants[idx3];
931 retval[j++] = '-';
932 retval[j++] = consonants[idx4];
933 seed = ((seed * 5) +
934 ((((u_int)(dgst_raw[2 * i])) * 7) +
935 ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
936 }
937 } else {
938 idx0 = seed % 6;
939 idx1 = 16;
940 idx2 = seed / 6;
941 retval[j++] = vowels[idx0];
942 retval[j++] = consonants[idx1];
943 retval[j++] = vowels[idx2];
944 }
945 }
946 retval[j++] = 'x';
947 retval[j++] = '\0';
948 return retval;
949 }
950
951 /*
952 * Draw an ASCII-Art representing the fingerprint so human brain can
953 * profit from its built-in pattern recognition ability.
954 * This technique is called "random art" and can be found in some
955 * scientific publications like this original paper:
956 *
957 * "Hash Visualization: a New Technique to improve Real-World Security",
958 * Perrig A. and Song D., 1999, International Workshop on Cryptographic
959 * Techniques and E-Commerce (CrypTEC '99)
960 * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
961 *
962 * The subject came up in a talk by Dan Kaminsky, too.
963 *
964 * If you see the picture is different, the key is different.
965 * If the picture looks the same, you still know nothing.
966 *
967 * The algorithm used here is a worm crawling over a discrete plane,
968 * leaving a trace (augmenting the field) everywhere it goes.
969 * Movement is taken from dgst_raw 2bit-wise. Bumping into walls
970 * makes the respective movement vector be ignored for this turn.
971 * Graphs are not unambiguous, because circles in graphs can be
972 * walked in either direction.
973 */
974
975 /*
976 * Field sizes for the random art. Have to be odd, so the starting point
977 * can be in the exact middle of the picture, and FLDBASE should be >=8 .
978 * Else pictures would be too dense, and drawing the frame would
979 * fail, too, because the key type would not fit in anymore.
980 */
981 #define FLDBASE 8
982 #define FLDSIZE_Y (FLDBASE + 1)
983 #define FLDSIZE_X (FLDBASE * 2 + 1)
984 static char *
fingerprint_randomart(const char * alg,u_char * dgst_raw,size_t dgst_raw_len,const struct sshkey * k)985 fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
986 const struct sshkey *k)
987 {
988 /*
989 * Chars to be used after each other every time the worm
990 * intersects with itself. Matter of taste.
991 */
992 char *augmentation_string = " .o+=*BOX@%&#/^SE";
993 char *retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
994 u_char field[FLDSIZE_X][FLDSIZE_Y];
995 size_t i, tlen, hlen;
996 u_int b;
997 int x, y, r;
998 size_t len = strlen(augmentation_string) - 1;
999
1000 if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
1001 return NULL;
1002
1003 /* initialize field */
1004 memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1005 x = FLDSIZE_X / 2;
1006 y = FLDSIZE_Y / 2;
1007
1008 /* process raw key */
1009 for (i = 0; i < dgst_raw_len; i++) {
1010 int input;
1011 /* each byte conveys four 2-bit move commands */
1012 input = dgst_raw[i];
1013 for (b = 0; b < 4; b++) {
1014 /* evaluate 2 bit, rest is shifted later */
1015 x += (input & 0x1) ? 1 : -1;
1016 y += (input & 0x2) ? 1 : -1;
1017
1018 /* assure we are still in bounds */
1019 x = MAXIMUM(x, 0);
1020 y = MAXIMUM(y, 0);
1021 x = MINIMUM(x, FLDSIZE_X - 1);
1022 y = MINIMUM(y, FLDSIZE_Y - 1);
1023
1024 /* augment the field */
1025 if (field[x][y] < len - 2)
1026 field[x][y]++;
1027 input = input >> 2;
1028 }
1029 }
1030
1031 /* mark starting point and end point*/
1032 field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
1033 field[x][y] = len;
1034
1035 /* assemble title */
1036 r = snprintf(title, sizeof(title), "[%s %u]",
1037 sshkey_type(k), sshkey_size(k));
1038 /* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */
1039 if (r < 0 || r > (int)sizeof(title))
1040 r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k));
1041 tlen = (r <= 0) ? 0 : strlen(title);
1042
1043 /* assemble hash ID. */
1044 r = snprintf(hash, sizeof(hash), "[%s]", alg);
1045 hlen = (r <= 0) ? 0 : strlen(hash);
1046
1047 /* output upper border */
1048 p = retval;
1049 *p++ = '+';
1050 for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
1051 *p++ = '-';
1052 memcpy(p, title, tlen);
1053 p += tlen;
1054 for (i += tlen; i < FLDSIZE_X; i++)
1055 *p++ = '-';
1056 *p++ = '+';
1057 *p++ = '\n';
1058
1059 /* output content */
1060 for (y = 0; y < FLDSIZE_Y; y++) {
1061 *p++ = '|';
1062 for (x = 0; x < FLDSIZE_X; x++)
1063 *p++ = augmentation_string[MINIMUM(field[x][y], len)];
1064 *p++ = '|';
1065 *p++ = '\n';
1066 }
1067
1068 /* output lower border */
1069 *p++ = '+';
1070 for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
1071 *p++ = '-';
1072 memcpy(p, hash, hlen);
1073 p += hlen;
1074 for (i += hlen; i < FLDSIZE_X; i++)
1075 *p++ = '-';
1076 *p++ = '+';
1077
1078 return retval;
1079 }
1080
1081 char *
sshkey_fingerprint(const struct sshkey * k,int dgst_alg,enum sshkey_fp_rep dgst_rep)1082 sshkey_fingerprint(const struct sshkey *k, int dgst_alg,
1083 enum sshkey_fp_rep dgst_rep)
1084 {
1085 char *retval = NULL;
1086 u_char *dgst_raw;
1087 size_t dgst_raw_len;
1088
1089 if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0)
1090 return NULL;
1091 switch (dgst_rep) {
1092 case SSH_FP_DEFAULT:
1093 if (dgst_alg == SSH_DIGEST_MD5) {
1094 retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1095 dgst_raw, dgst_raw_len);
1096 } else {
1097 retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1098 dgst_raw, dgst_raw_len);
1099 }
1100 break;
1101 case SSH_FP_HEX:
1102 retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1103 dgst_raw, dgst_raw_len);
1104 break;
1105 case SSH_FP_BASE64:
1106 retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1107 dgst_raw, dgst_raw_len);
1108 break;
1109 case SSH_FP_BUBBLEBABBLE:
1110 retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1111 break;
1112 case SSH_FP_RANDOMART:
1113 retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg),
1114 dgst_raw, dgst_raw_len, k);
1115 break;
1116 default:
1117 freezero(dgst_raw, dgst_raw_len);
1118 return NULL;
1119 }
1120 freezero(dgst_raw, dgst_raw_len);
1121 return retval;
1122 }
1123
1124 static int
peek_type_nid(const char * s,size_t l,int * nid)1125 peek_type_nid(const char *s, size_t l, int *nid)
1126 {
1127 const struct sshkey_impl *impl;
1128 int i;
1129
1130 for (i = 0; keyimpls[i] != NULL; i++) {
1131 impl = keyimpls[i];
1132 if (impl->name == NULL || strlen(impl->name) != l)
1133 continue;
1134 if (memcmp(s, impl->name, l) == 0) {
1135 *nid = -1;
1136 if (key_type_is_ecdsa_variant(impl->type))
1137 *nid = impl->nid;
1138 return impl->type;
1139 }
1140 }
1141 return KEY_UNSPEC;
1142 }
1143
1144 /* XXX this can now be made const char * */
1145 int
sshkey_read(struct sshkey * ret,char ** cpp)1146 sshkey_read(struct sshkey *ret, char **cpp)
1147 {
1148 struct sshkey *k;
1149 char *cp, *blobcopy;
1150 size_t space;
1151 int r, type, curve_nid = -1;
1152 struct sshbuf *blob;
1153
1154 if (ret == NULL)
1155 return SSH_ERR_INVALID_ARGUMENT;
1156 if (ret->type != KEY_UNSPEC && sshkey_impl_from_type(ret->type) == NULL)
1157 return SSH_ERR_INVALID_ARGUMENT;
1158
1159 /* Decode type */
1160 cp = *cpp;
1161 space = strcspn(cp, " \t");
1162 if (space == strlen(cp))
1163 return SSH_ERR_INVALID_FORMAT;
1164 if ((type = peek_type_nid(cp, space, &curve_nid)) == KEY_UNSPEC)
1165 return SSH_ERR_INVALID_FORMAT;
1166
1167 /* skip whitespace */
1168 for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
1169 ;
1170 if (*cp == '\0')
1171 return SSH_ERR_INVALID_FORMAT;
1172 if (ret->type != KEY_UNSPEC && ret->type != type)
1173 return SSH_ERR_KEY_TYPE_MISMATCH;
1174 if ((blob = sshbuf_new()) == NULL)
1175 return SSH_ERR_ALLOC_FAIL;
1176
1177 /* find end of keyblob and decode */
1178 space = strcspn(cp, " \t");
1179 if ((blobcopy = strndup(cp, space)) == NULL) {
1180 sshbuf_free(blob);
1181 return SSH_ERR_ALLOC_FAIL;
1182 }
1183 if ((r = sshbuf_b64tod(blob, blobcopy)) != 0) {
1184 free(blobcopy);
1185 sshbuf_free(blob);
1186 return r;
1187 }
1188 free(blobcopy);
1189 if ((r = sshkey_fromb(blob, &k)) != 0) {
1190 sshbuf_free(blob);
1191 return r;
1192 }
1193 sshbuf_free(blob);
1194
1195 /* skip whitespace and leave cp at start of comment */
1196 for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
1197 ;
1198
1199 /* ensure type of blob matches type at start of line */
1200 if (k->type != type) {
1201 sshkey_free(k);
1202 return SSH_ERR_KEY_TYPE_MISMATCH;
1203 }
1204 if (key_type_is_ecdsa_variant(type) && curve_nid != k->ecdsa_nid) {
1205 sshkey_free(k);
1206 return SSH_ERR_EC_CURVE_MISMATCH;
1207 }
1208
1209 /* Fill in ret from parsed key */
1210 sshkey_free_contents(ret);
1211 *ret = *k;
1212 freezero(k, sizeof(*k));
1213
1214 /* success */
1215 *cpp = cp;
1216 return 0;
1217 }
1218
1219 int
sshkey_to_base64(const struct sshkey * key,char ** b64p)1220 sshkey_to_base64(const struct sshkey *key, char **b64p)
1221 {
1222 int r = SSH_ERR_INTERNAL_ERROR;
1223 struct sshbuf *b = NULL;
1224 char *uu = NULL;
1225
1226 if (b64p != NULL)
1227 *b64p = NULL;
1228 if ((b = sshbuf_new()) == NULL)
1229 return SSH_ERR_ALLOC_FAIL;
1230 if ((r = sshkey_putb(key, b)) != 0)
1231 goto out;
1232 if ((uu = sshbuf_dtob64_string(b, 0)) == NULL) {
1233 r = SSH_ERR_ALLOC_FAIL;
1234 goto out;
1235 }
1236 /* Success */
1237 if (b64p != NULL) {
1238 *b64p = uu;
1239 uu = NULL;
1240 }
1241 r = 0;
1242 out:
1243 sshbuf_free(b);
1244 free(uu);
1245 return r;
1246 }
1247
1248 int
sshkey_format_text(const struct sshkey * key,struct sshbuf * b)1249 sshkey_format_text(const struct sshkey *key, struct sshbuf *b)
1250 {
1251 int r = SSH_ERR_INTERNAL_ERROR;
1252 char *uu = NULL;
1253
1254 if ((r = sshkey_to_base64(key, &uu)) != 0)
1255 goto out;
1256 if ((r = sshbuf_putf(b, "%s %s",
1257 sshkey_ssh_name(key), uu)) != 0)
1258 goto out;
1259 r = 0;
1260 out:
1261 free(uu);
1262 return r;
1263 }
1264
1265 int
sshkey_write(const struct sshkey * key,FILE * f)1266 sshkey_write(const struct sshkey *key, FILE *f)
1267 {
1268 struct sshbuf *b = NULL;
1269 int r = SSH_ERR_INTERNAL_ERROR;
1270
1271 if ((b = sshbuf_new()) == NULL)
1272 return SSH_ERR_ALLOC_FAIL;
1273 if ((r = sshkey_format_text(key, b)) != 0)
1274 goto out;
1275 if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) {
1276 if (feof(f))
1277 errno = EPIPE;
1278 r = SSH_ERR_SYSTEM_ERROR;
1279 goto out;
1280 }
1281 /* Success */
1282 r = 0;
1283 out:
1284 sshbuf_free(b);
1285 return r;
1286 }
1287
1288 const char *
sshkey_cert_type(const struct sshkey * k)1289 sshkey_cert_type(const struct sshkey *k)
1290 {
1291 switch (k->cert->type) {
1292 case SSH2_CERT_TYPE_USER:
1293 return "user";
1294 case SSH2_CERT_TYPE_HOST:
1295 return "host";
1296 default:
1297 return "unknown";
1298 }
1299 }
1300
1301 int
sshkey_check_rsa_length(const struct sshkey * k,int min_size)1302 sshkey_check_rsa_length(const struct sshkey *k, int min_size)
1303 {
1304 #ifdef WITH_OPENSSL
1305 const BIGNUM *rsa_n;
1306 int nbits;
1307
1308 if (k == NULL || k->rsa == NULL ||
1309 (k->type != KEY_RSA && k->type != KEY_RSA_CERT))
1310 return 0;
1311 RSA_get0_key(k->rsa, &rsa_n, NULL, NULL);
1312 nbits = BN_num_bits(rsa_n);
1313 if (nbits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
1314 (min_size > 0 && nbits < min_size))
1315 return SSH_ERR_KEY_LENGTH;
1316 #endif /* WITH_OPENSSL */
1317 return 0;
1318 }
1319
1320 #ifdef WITH_OPENSSL
1321 int
sshkey_ecdsa_key_to_nid(EC_KEY * k)1322 sshkey_ecdsa_key_to_nid(EC_KEY *k)
1323 {
1324 EC_GROUP *eg;
1325 int nids[] = {
1326 NID_X9_62_prime256v1,
1327 NID_secp384r1,
1328 NID_secp521r1,
1329 -1
1330 };
1331 int nid;
1332 u_int i;
1333 const EC_GROUP *g = EC_KEY_get0_group(k);
1334
1335 /*
1336 * The group may be stored in a ASN.1 encoded private key in one of two
1337 * ways: as a "named group", which is reconstituted by ASN.1 object ID
1338 * or explicit group parameters encoded into the key blob. Only the
1339 * "named group" case sets the group NID for us, but we can figure
1340 * it out for the other case by comparing against all the groups that
1341 * are supported.
1342 */
1343 if ((nid = EC_GROUP_get_curve_name(g)) > 0)
1344 return nid;
1345 for (i = 0; nids[i] != -1; i++) {
1346 if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL)
1347 return -1;
1348 if (EC_GROUP_cmp(g, eg, NULL) == 0)
1349 break;
1350 EC_GROUP_free(eg);
1351 }
1352 if (nids[i] != -1) {
1353 /* Use the group with the NID attached */
1354 EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
1355 if (EC_KEY_set_group(k, eg) != 1) {
1356 EC_GROUP_free(eg);
1357 return -1;
1358 }
1359 }
1360 return nids[i];
1361 }
1362 #endif /* WITH_OPENSSL */
1363
1364 int
sshkey_generate(int type,u_int bits,struct sshkey ** keyp)1365 sshkey_generate(int type, u_int bits, struct sshkey **keyp)
1366 {
1367 struct sshkey *k;
1368 int ret = SSH_ERR_INTERNAL_ERROR;
1369 const struct sshkey_impl *impl;
1370
1371 if (keyp == NULL || sshkey_type_is_cert(type))
1372 return SSH_ERR_INVALID_ARGUMENT;
1373 *keyp = NULL;
1374 if ((impl = sshkey_impl_from_type(type)) == NULL)
1375 return SSH_ERR_KEY_TYPE_UNKNOWN;
1376 if (impl->funcs->generate == NULL)
1377 return SSH_ERR_FEATURE_UNSUPPORTED;
1378 if ((k = sshkey_new(KEY_UNSPEC)) == NULL)
1379 return SSH_ERR_ALLOC_FAIL;
1380 k->type = type;
1381 if ((ret = impl->funcs->generate(k, bits)) != 0) {
1382 sshkey_free(k);
1383 return ret;
1384 }
1385 /* success */
1386 *keyp = k;
1387 return 0;
1388 }
1389
1390 int
sshkey_cert_copy(const struct sshkey * from_key,struct sshkey * to_key)1391 sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key)
1392 {
1393 u_int i;
1394 const struct sshkey_cert *from;
1395 struct sshkey_cert *to;
1396 int r = SSH_ERR_INTERNAL_ERROR;
1397
1398 if (to_key == NULL || (from = from_key->cert) == NULL)
1399 return SSH_ERR_INVALID_ARGUMENT;
1400
1401 if ((to = cert_new()) == NULL)
1402 return SSH_ERR_ALLOC_FAIL;
1403
1404 if ((r = sshbuf_putb(to->certblob, from->certblob)) != 0 ||
1405 (r = sshbuf_putb(to->critical, from->critical)) != 0 ||
1406 (r = sshbuf_putb(to->extensions, from->extensions)) != 0)
1407 goto out;
1408
1409 to->serial = from->serial;
1410 to->type = from->type;
1411 if (from->key_id == NULL)
1412 to->key_id = NULL;
1413 else if ((to->key_id = strdup(from->key_id)) == NULL) {
1414 r = SSH_ERR_ALLOC_FAIL;
1415 goto out;
1416 }
1417 to->valid_after = from->valid_after;
1418 to->valid_before = from->valid_before;
1419 if (from->signature_key == NULL)
1420 to->signature_key = NULL;
1421 else if ((r = sshkey_from_private(from->signature_key,
1422 &to->signature_key)) != 0)
1423 goto out;
1424 if (from->signature_type != NULL &&
1425 (to->signature_type = strdup(from->signature_type)) == NULL) {
1426 r = SSH_ERR_ALLOC_FAIL;
1427 goto out;
1428 }
1429 if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS) {
1430 r = SSH_ERR_INVALID_ARGUMENT;
1431 goto out;
1432 }
1433 if (from->nprincipals > 0) {
1434 if ((to->principals = calloc(from->nprincipals,
1435 sizeof(*to->principals))) == NULL) {
1436 r = SSH_ERR_ALLOC_FAIL;
1437 goto out;
1438 }
1439 for (i = 0; i < from->nprincipals; i++) {
1440 to->principals[i] = strdup(from->principals[i]);
1441 if (to->principals[i] == NULL) {
1442 to->nprincipals = i;
1443 r = SSH_ERR_ALLOC_FAIL;
1444 goto out;
1445 }
1446 }
1447 }
1448 to->nprincipals = from->nprincipals;
1449
1450 /* success */
1451 cert_free(to_key->cert);
1452 to_key->cert = to;
1453 to = NULL;
1454 r = 0;
1455 out:
1456 cert_free(to);
1457 return r;
1458 }
1459
1460 int
sshkey_copy_public_sk(const struct sshkey * from,struct sshkey * to)1461 sshkey_copy_public_sk(const struct sshkey *from, struct sshkey *to)
1462 {
1463 /* Append security-key application string */
1464 if ((to->sk_application = strdup(from->sk_application)) == NULL)
1465 return SSH_ERR_ALLOC_FAIL;
1466 return 0;
1467 }
1468
1469 int
sshkey_from_private(const struct sshkey * k,struct sshkey ** pkp)1470 sshkey_from_private(const struct sshkey *k, struct sshkey **pkp)
1471 {
1472 struct sshkey *n = NULL;
1473 int r = SSH_ERR_INTERNAL_ERROR;
1474 const struct sshkey_impl *impl;
1475
1476 *pkp = NULL;
1477 if ((impl = sshkey_impl_from_key(k)) == NULL)
1478 return SSH_ERR_KEY_TYPE_UNKNOWN;
1479 if ((n = sshkey_new(k->type)) == NULL) {
1480 r = SSH_ERR_ALLOC_FAIL;
1481 goto out;
1482 }
1483 if ((r = impl->funcs->copy_public(k, n)) != 0)
1484 goto out;
1485 if (sshkey_is_cert(k) && (r = sshkey_cert_copy(k, n)) != 0)
1486 goto out;
1487 /* success */
1488 *pkp = n;
1489 n = NULL;
1490 r = 0;
1491 out:
1492 sshkey_free(n);
1493 return r;
1494 }
1495
1496 int
sshkey_is_shielded(struct sshkey * k)1497 sshkey_is_shielded(struct sshkey *k)
1498 {
1499 return k != NULL && k->shielded_private != NULL;
1500 }
1501
1502 int
sshkey_shield_private(struct sshkey * k)1503 sshkey_shield_private(struct sshkey *k)
1504 {
1505 struct sshbuf *prvbuf = NULL;
1506 u_char *prekey = NULL, *enc = NULL, keyiv[SSH_DIGEST_MAX_LENGTH];
1507 struct sshcipher_ctx *cctx = NULL;
1508 const struct sshcipher *cipher;
1509 size_t i, enclen = 0;
1510 struct sshkey *kswap = NULL, tmp;
1511 int r = SSH_ERR_INTERNAL_ERROR;
1512
1513 #ifdef DEBUG_PK
1514 fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k));
1515 #endif
1516 if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) {
1517 r = SSH_ERR_INVALID_ARGUMENT;
1518 goto out;
1519 }
1520 if (cipher_keylen(cipher) + cipher_ivlen(cipher) >
1521 ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) {
1522 r = SSH_ERR_INTERNAL_ERROR;
1523 goto out;
1524 }
1525
1526 /* Prepare a random pre-key, and from it an ephemeral key */
1527 if ((prekey = malloc(SSHKEY_SHIELD_PREKEY_LEN)) == NULL) {
1528 r = SSH_ERR_ALLOC_FAIL;
1529 goto out;
1530 }
1531 arc4random_buf(prekey, SSHKEY_SHIELD_PREKEY_LEN);
1532 if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH,
1533 prekey, SSHKEY_SHIELD_PREKEY_LEN,
1534 keyiv, SSH_DIGEST_MAX_LENGTH)) != 0)
1535 goto out;
1536 #ifdef DEBUG_PK
1537 fprintf(stderr, "%s: key+iv\n", __func__);
1538 sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH),
1539 stderr);
1540 #endif
1541 if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher),
1542 keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 1)) != 0)
1543 goto out;
1544
1545 /* Serialise and encrypt the private key using the ephemeral key */
1546 if ((prvbuf = sshbuf_new()) == NULL) {
1547 r = SSH_ERR_ALLOC_FAIL;
1548 goto out;
1549 }
1550 if (sshkey_is_shielded(k) && (r = sshkey_unshield_private(k)) != 0)
1551 goto out;
1552 if ((r = sshkey_private_serialize_opt(k, prvbuf,
1553 SSHKEY_SERIALIZE_SHIELD)) != 0)
1554 goto out;
1555 /* pad to cipher blocksize */
1556 i = 0;
1557 while (sshbuf_len(prvbuf) % cipher_blocksize(cipher)) {
1558 if ((r = sshbuf_put_u8(prvbuf, ++i & 0xff)) != 0)
1559 goto out;
1560 }
1561 #ifdef DEBUG_PK
1562 fprintf(stderr, "%s: serialised\n", __func__);
1563 sshbuf_dump(prvbuf, stderr);
1564 #endif
1565 /* encrypt */
1566 enclen = sshbuf_len(prvbuf);
1567 if ((enc = malloc(enclen)) == NULL) {
1568 r = SSH_ERR_ALLOC_FAIL;
1569 goto out;
1570 }
1571 if ((r = cipher_crypt(cctx, 0, enc,
1572 sshbuf_ptr(prvbuf), sshbuf_len(prvbuf), 0, 0)) != 0)
1573 goto out;
1574 #ifdef DEBUG_PK
1575 fprintf(stderr, "%s: encrypted\n", __func__);
1576 sshbuf_dump_data(enc, enclen, stderr);
1577 #endif
1578
1579 /* Make a scrubbed, public-only copy of our private key argument */
1580 if ((r = sshkey_from_private(k, &kswap)) != 0)
1581 goto out;
1582
1583 /* Swap the private key out (it will be destroyed below) */
1584 tmp = *kswap;
1585 *kswap = *k;
1586 *k = tmp;
1587
1588 /* Insert the shielded key into our argument */
1589 k->shielded_private = enc;
1590 k->shielded_len = enclen;
1591 k->shield_prekey = prekey;
1592 k->shield_prekey_len = SSHKEY_SHIELD_PREKEY_LEN;
1593 enc = prekey = NULL; /* transferred */
1594 enclen = 0;
1595
1596 /* preserve key fields that are required for correct operation */
1597 k->sk_flags = kswap->sk_flags;
1598
1599 /* success */
1600 r = 0;
1601
1602 out:
1603 /* XXX behaviour on error - invalidate original private key? */
1604 cipher_free(cctx);
1605 explicit_bzero(keyiv, sizeof(keyiv));
1606 explicit_bzero(&tmp, sizeof(tmp));
1607 freezero(enc, enclen);
1608 freezero(prekey, SSHKEY_SHIELD_PREKEY_LEN);
1609 sshkey_free(kswap);
1610 sshbuf_free(prvbuf);
1611 return r;
1612 }
1613
1614 /* Check deterministic padding after private key */
1615 static int
private2_check_padding(struct sshbuf * decrypted)1616 private2_check_padding(struct sshbuf *decrypted)
1617 {
1618 u_char pad;
1619 size_t i;
1620 int r;
1621
1622 i = 0;
1623 while (sshbuf_len(decrypted)) {
1624 if ((r = sshbuf_get_u8(decrypted, &pad)) != 0)
1625 goto out;
1626 if (pad != (++i & 0xff)) {
1627 r = SSH_ERR_INVALID_FORMAT;
1628 goto out;
1629 }
1630 }
1631 /* success */
1632 r = 0;
1633 out:
1634 explicit_bzero(&pad, sizeof(pad));
1635 explicit_bzero(&i, sizeof(i));
1636 return r;
1637 }
1638
1639 int
sshkey_unshield_private(struct sshkey * k)1640 sshkey_unshield_private(struct sshkey *k)
1641 {
1642 struct sshbuf *prvbuf = NULL;
1643 u_char *cp, keyiv[SSH_DIGEST_MAX_LENGTH];
1644 struct sshcipher_ctx *cctx = NULL;
1645 const struct sshcipher *cipher;
1646 struct sshkey *kswap = NULL, tmp;
1647 int r = SSH_ERR_INTERNAL_ERROR;
1648
1649 #ifdef DEBUG_PK
1650 fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k));
1651 #endif
1652 if (!sshkey_is_shielded(k))
1653 return 0; /* nothing to do */
1654
1655 if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) {
1656 r = SSH_ERR_INVALID_ARGUMENT;
1657 goto out;
1658 }
1659 if (cipher_keylen(cipher) + cipher_ivlen(cipher) >
1660 ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) {
1661 r = SSH_ERR_INTERNAL_ERROR;
1662 goto out;
1663 }
1664 /* check size of shielded key blob */
1665 if (k->shielded_len < cipher_blocksize(cipher) ||
1666 (k->shielded_len % cipher_blocksize(cipher)) != 0) {
1667 r = SSH_ERR_INVALID_FORMAT;
1668 goto out;
1669 }
1670
1671 /* Calculate the ephemeral key from the prekey */
1672 if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH,
1673 k->shield_prekey, k->shield_prekey_len,
1674 keyiv, SSH_DIGEST_MAX_LENGTH)) != 0)
1675 goto out;
1676 if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher),
1677 keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 0)) != 0)
1678 goto out;
1679 #ifdef DEBUG_PK
1680 fprintf(stderr, "%s: key+iv\n", __func__);
1681 sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH),
1682 stderr);
1683 #endif
1684
1685 /* Decrypt and parse the shielded private key using the ephemeral key */
1686 if ((prvbuf = sshbuf_new()) == NULL) {
1687 r = SSH_ERR_ALLOC_FAIL;
1688 goto out;
1689 }
1690 if ((r = sshbuf_reserve(prvbuf, k->shielded_len, &cp)) != 0)
1691 goto out;
1692 /* decrypt */
1693 #ifdef DEBUG_PK
1694 fprintf(stderr, "%s: encrypted\n", __func__);
1695 sshbuf_dump_data(k->shielded_private, k->shielded_len, stderr);
1696 #endif
1697 if ((r = cipher_crypt(cctx, 0, cp,
1698 k->shielded_private, k->shielded_len, 0, 0)) != 0)
1699 goto out;
1700 #ifdef DEBUG_PK
1701 fprintf(stderr, "%s: serialised\n", __func__);
1702 sshbuf_dump(prvbuf, stderr);
1703 #endif
1704 /* Parse private key */
1705 if ((r = sshkey_private_deserialize(prvbuf, &kswap)) != 0)
1706 goto out;
1707
1708 if ((r = private2_check_padding(prvbuf)) != 0)
1709 goto out;
1710
1711 /* Swap the parsed key back into place */
1712 tmp = *kswap;
1713 *kswap = *k;
1714 *k = tmp;
1715
1716 /* success */
1717 r = 0;
1718
1719 out:
1720 cipher_free(cctx);
1721 explicit_bzero(keyiv, sizeof(keyiv));
1722 explicit_bzero(&tmp, sizeof(tmp));
1723 sshkey_free(kswap);
1724 sshbuf_free(prvbuf);
1725 return r;
1726 }
1727
1728 static int
cert_parse(struct sshbuf * b,struct sshkey * key,struct sshbuf * certbuf)1729 cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
1730 {
1731 struct sshbuf *principals = NULL, *crit = NULL;
1732 struct sshbuf *exts = NULL, *ca = NULL;
1733 u_char *sig = NULL;
1734 size_t signed_len = 0, slen = 0, kidlen = 0;
1735 int ret = SSH_ERR_INTERNAL_ERROR;
1736
1737 /* Copy the entire key blob for verification and later serialisation */
1738 if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0)
1739 return ret;
1740
1741 /* Parse body of certificate up to signature */
1742 if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 ||
1743 (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 ||
1744 (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 ||
1745 (ret = sshbuf_froms(b, &principals)) != 0 ||
1746 (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 ||
1747 (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 ||
1748 (ret = sshbuf_froms(b, &crit)) != 0 ||
1749 (ret = sshbuf_froms(b, &exts)) != 0 ||
1750 (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 ||
1751 (ret = sshbuf_froms(b, &ca)) != 0) {
1752 /* XXX debug print error for ret */
1753 ret = SSH_ERR_INVALID_FORMAT;
1754 goto out;
1755 }
1756
1757 /* Signature is left in the buffer so we can calculate this length */
1758 signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b);
1759
1760 if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) {
1761 ret = SSH_ERR_INVALID_FORMAT;
1762 goto out;
1763 }
1764
1765 if (key->cert->type != SSH2_CERT_TYPE_USER &&
1766 key->cert->type != SSH2_CERT_TYPE_HOST) {
1767 ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE;
1768 goto out;
1769 }
1770
1771 /* Parse principals section */
1772 while (sshbuf_len(principals) > 0) {
1773 char *principal = NULL;
1774 char **oprincipals = NULL;
1775
1776 if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) {
1777 ret = SSH_ERR_INVALID_FORMAT;
1778 goto out;
1779 }
1780 if ((ret = sshbuf_get_cstring(principals, &principal,
1781 NULL)) != 0) {
1782 ret = SSH_ERR_INVALID_FORMAT;
1783 goto out;
1784 }
1785 oprincipals = key->cert->principals;
1786 key->cert->principals = recallocarray(key->cert->principals,
1787 key->cert->nprincipals, key->cert->nprincipals + 1,
1788 sizeof(*key->cert->principals));
1789 if (key->cert->principals == NULL) {
1790 free(principal);
1791 key->cert->principals = oprincipals;
1792 ret = SSH_ERR_ALLOC_FAIL;
1793 goto out;
1794 }
1795 key->cert->principals[key->cert->nprincipals++] = principal;
1796 }
1797
1798 /*
1799 * Stash a copies of the critical options and extensions sections
1800 * for later use.
1801 */
1802 if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 ||
1803 (exts != NULL &&
1804 (ret = sshbuf_putb(key->cert->extensions, exts)) != 0))
1805 goto out;
1806
1807 /*
1808 * Validate critical options and extensions sections format.
1809 */
1810 while (sshbuf_len(crit) != 0) {
1811 if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 ||
1812 (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) {
1813 sshbuf_reset(key->cert->critical);
1814 ret = SSH_ERR_INVALID_FORMAT;
1815 goto out;
1816 }
1817 }
1818 while (exts != NULL && sshbuf_len(exts) != 0) {
1819 if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 ||
1820 (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) {
1821 sshbuf_reset(key->cert->extensions);
1822 ret = SSH_ERR_INVALID_FORMAT;
1823 goto out;
1824 }
1825 }
1826
1827 /* Parse CA key and check signature */
1828 if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) {
1829 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1830 goto out;
1831 }
1832 if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) {
1833 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1834 goto out;
1835 }
1836 if ((ret = sshkey_verify(key->cert->signature_key, sig, slen,
1837 sshbuf_ptr(key->cert->certblob), signed_len, NULL, 0, NULL)) != 0)
1838 goto out;
1839 if ((ret = sshkey_get_sigtype(sig, slen,
1840 &key->cert->signature_type)) != 0)
1841 goto out;
1842
1843 /* Success */
1844 ret = 0;
1845 out:
1846 sshbuf_free(ca);
1847 sshbuf_free(crit);
1848 sshbuf_free(exts);
1849 sshbuf_free(principals);
1850 free(sig);
1851 return ret;
1852 }
1853
1854 int
sshkey_deserialize_sk(struct sshbuf * b,struct sshkey * key)1855 sshkey_deserialize_sk(struct sshbuf *b, struct sshkey *key)
1856 {
1857 /* Parse additional security-key application string */
1858 if (sshbuf_get_cstring(b, &key->sk_application, NULL) != 0)
1859 return SSH_ERR_INVALID_FORMAT;
1860 return 0;
1861 }
1862
1863 static int
sshkey_from_blob_internal(struct sshbuf * b,struct sshkey ** keyp,int allow_cert)1864 sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
1865 int allow_cert)
1866 {
1867 int type, ret = SSH_ERR_INTERNAL_ERROR;
1868 char *ktype = NULL;
1869 struct sshkey *key = NULL;
1870 struct sshbuf *copy;
1871 const struct sshkey_impl *impl;
1872
1873 #ifdef DEBUG_PK /* XXX */
1874 sshbuf_dump(b, stderr);
1875 #endif
1876 if (keyp != NULL)
1877 *keyp = NULL;
1878 if ((copy = sshbuf_fromb(b)) == NULL) {
1879 ret = SSH_ERR_ALLOC_FAIL;
1880 goto out;
1881 }
1882 if (sshbuf_get_cstring(b, &ktype, NULL) != 0) {
1883 ret = SSH_ERR_INVALID_FORMAT;
1884 goto out;
1885 }
1886
1887 type = sshkey_type_from_name(ktype);
1888 if (!allow_cert && sshkey_type_is_cert(type)) {
1889 ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1890 goto out;
1891 }
1892 if ((impl = sshkey_impl_from_type(type)) == NULL) {
1893 ret = SSH_ERR_KEY_TYPE_UNKNOWN;
1894 goto out;
1895 }
1896 if ((key = sshkey_new(type)) == NULL) {
1897 ret = SSH_ERR_ALLOC_FAIL;
1898 goto out;
1899 }
1900 if (sshkey_type_is_cert(type)) {
1901 /* Skip nonce that precedes all certificates */
1902 if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
1903 ret = SSH_ERR_INVALID_FORMAT;
1904 goto out;
1905 }
1906 }
1907 if ((ret = impl->funcs->deserialize_public(ktype, b, key)) != 0)
1908 goto out;
1909
1910 /* Parse certificate potion */
1911 if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0)
1912 goto out;
1913
1914 if (key != NULL && sshbuf_len(b) != 0) {
1915 ret = SSH_ERR_INVALID_FORMAT;
1916 goto out;
1917 }
1918 ret = 0;
1919 if (keyp != NULL) {
1920 *keyp = key;
1921 key = NULL;
1922 }
1923 out:
1924 sshbuf_free(copy);
1925 sshkey_free(key);
1926 free(ktype);
1927 return ret;
1928 }
1929
1930 int
sshkey_from_blob(const u_char * blob,size_t blen,struct sshkey ** keyp)1931 sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp)
1932 {
1933 struct sshbuf *b;
1934 int r;
1935
1936 if ((b = sshbuf_from(blob, blen)) == NULL)
1937 return SSH_ERR_ALLOC_FAIL;
1938 r = sshkey_from_blob_internal(b, keyp, 1);
1939 sshbuf_free(b);
1940 return r;
1941 }
1942
1943 int
sshkey_fromb(struct sshbuf * b,struct sshkey ** keyp)1944 sshkey_fromb(struct sshbuf *b, struct sshkey **keyp)
1945 {
1946 return sshkey_from_blob_internal(b, keyp, 1);
1947 }
1948
1949 int
sshkey_froms(struct sshbuf * buf,struct sshkey ** keyp)1950 sshkey_froms(struct sshbuf *buf, struct sshkey **keyp)
1951 {
1952 struct sshbuf *b;
1953 int r;
1954
1955 if ((r = sshbuf_froms(buf, &b)) != 0)
1956 return r;
1957 r = sshkey_from_blob_internal(b, keyp, 1);
1958 sshbuf_free(b);
1959 return r;
1960 }
1961
1962 int
sshkey_get_sigtype(const u_char * sig,size_t siglen,char ** sigtypep)1963 sshkey_get_sigtype(const u_char *sig, size_t siglen, char **sigtypep)
1964 {
1965 int r;
1966 struct sshbuf *b = NULL;
1967 char *sigtype = NULL;
1968
1969 if (sigtypep != NULL)
1970 *sigtypep = NULL;
1971 if ((b = sshbuf_from(sig, siglen)) == NULL)
1972 return SSH_ERR_ALLOC_FAIL;
1973 if ((r = sshbuf_get_cstring(b, &sigtype, NULL)) != 0)
1974 goto out;
1975 /* success */
1976 if (sigtypep != NULL) {
1977 *sigtypep = sigtype;
1978 sigtype = NULL;
1979 }
1980 r = 0;
1981 out:
1982 free(sigtype);
1983 sshbuf_free(b);
1984 return r;
1985 }
1986
1987 /*
1988 *
1989 * Checks whether a certificate's signature type is allowed.
1990 * Returns 0 (success) if the certificate signature type appears in the
1991 * "allowed" pattern-list, or the key is not a certificate to begin with.
1992 * Otherwise returns a ssherr.h code.
1993 */
1994 int
sshkey_check_cert_sigtype(const struct sshkey * key,const char * allowed)1995 sshkey_check_cert_sigtype(const struct sshkey *key, const char *allowed)
1996 {
1997 if (key == NULL || allowed == NULL)
1998 return SSH_ERR_INVALID_ARGUMENT;
1999 if (!sshkey_type_is_cert(key->type))
2000 return 0;
2001 if (key->cert == NULL || key->cert->signature_type == NULL)
2002 return SSH_ERR_INVALID_ARGUMENT;
2003 if (match_pattern_list(key->cert->signature_type, allowed, 0) != 1)
2004 return SSH_ERR_SIGN_ALG_UNSUPPORTED;
2005 return 0;
2006 }
2007
2008 /*
2009 * Returns the expected signature algorithm for a given public key algorithm.
2010 */
2011 const char *
sshkey_sigalg_by_name(const char * name)2012 sshkey_sigalg_by_name(const char *name)
2013 {
2014 const struct sshkey_impl *impl;
2015 int i;
2016
2017 for (i = 0; keyimpls[i] != NULL; i++) {
2018 impl = keyimpls[i];
2019 if (strcmp(impl->name, name) != 0)
2020 continue;
2021 if (impl->sigalg != NULL)
2022 return impl->sigalg;
2023 if (!impl->cert)
2024 return impl->name;
2025 return sshkey_ssh_name_from_type_nid(
2026 sshkey_type_plain(impl->type), impl->nid);
2027 }
2028 return NULL;
2029 }
2030
2031 /*
2032 * Verifies that the signature algorithm appearing inside the signature blob
2033 * matches that which was requested.
2034 */
2035 int
sshkey_check_sigtype(const u_char * sig,size_t siglen,const char * requested_alg)2036 sshkey_check_sigtype(const u_char *sig, size_t siglen,
2037 const char *requested_alg)
2038 {
2039 const char *expected_alg;
2040 char *sigtype = NULL;
2041 int r;
2042
2043 if (requested_alg == NULL)
2044 return 0;
2045 if ((expected_alg = sshkey_sigalg_by_name(requested_alg)) == NULL)
2046 return SSH_ERR_INVALID_ARGUMENT;
2047 if ((r = sshkey_get_sigtype(sig, siglen, &sigtype)) != 0)
2048 return r;
2049 r = strcmp(expected_alg, sigtype) == 0;
2050 free(sigtype);
2051 return r ? 0 : SSH_ERR_SIGN_ALG_UNSUPPORTED;
2052 }
2053
2054 int
sshkey_sign(struct sshkey * key,u_char ** sigp,size_t * lenp,const u_char * data,size_t datalen,const char * alg,const char * sk_provider,const char * sk_pin,u_int compat)2055 sshkey_sign(struct sshkey *key,
2056 u_char **sigp, size_t *lenp,
2057 const u_char *data, size_t datalen,
2058 const char *alg, const char *sk_provider, const char *sk_pin, u_int compat)
2059 {
2060 int was_shielded = sshkey_is_shielded(key);
2061 int r2, r = SSH_ERR_INTERNAL_ERROR;
2062 const struct sshkey_impl *impl;
2063
2064 if (sigp != NULL)
2065 *sigp = NULL;
2066 if (lenp != NULL)
2067 *lenp = 0;
2068 if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2069 return SSH_ERR_INVALID_ARGUMENT;
2070 if ((impl = sshkey_impl_from_key(key)) == NULL)
2071 return SSH_ERR_KEY_TYPE_UNKNOWN;
2072 if ((r = sshkey_unshield_private(key)) != 0)
2073 return r;
2074 if (sshkey_is_sk(key)) {
2075 r = sshsk_sign(sk_provider, key, sigp, lenp, data,
2076 datalen, compat, sk_pin);
2077 } else {
2078 if (impl->funcs->sign == NULL)
2079 r = SSH_ERR_SIGN_ALG_UNSUPPORTED;
2080 else {
2081 r = impl->funcs->sign(key, sigp, lenp, data, datalen,
2082 alg, sk_provider, sk_pin, compat);
2083 }
2084 }
2085 if (was_shielded && (r2 = sshkey_shield_private(key)) != 0)
2086 return r2;
2087 return r;
2088 }
2089
2090 /*
2091 * ssh_key_verify returns 0 for a correct signature and < 0 on error.
2092 * If "alg" specified, then the signature must use that algorithm.
2093 */
2094 int
sshkey_verify(const struct sshkey * key,const u_char * sig,size_t siglen,const u_char * data,size_t dlen,const char * alg,u_int compat,struct sshkey_sig_details ** detailsp)2095 sshkey_verify(const struct sshkey *key,
2096 const u_char *sig, size_t siglen,
2097 const u_char *data, size_t dlen, const char *alg, u_int compat,
2098 struct sshkey_sig_details **detailsp)
2099 {
2100 const struct sshkey_impl *impl;
2101
2102 if (detailsp != NULL)
2103 *detailsp = NULL;
2104 if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2105 return SSH_ERR_INVALID_ARGUMENT;
2106 if ((impl = sshkey_impl_from_key(key)) == NULL)
2107 return SSH_ERR_KEY_TYPE_UNKNOWN;
2108 return impl->funcs->verify(key, sig, siglen, data, dlen,
2109 alg, compat, detailsp);
2110 }
2111
2112 /* Convert a plain key to their _CERT equivalent */
2113 int
sshkey_to_certified(struct sshkey * k)2114 sshkey_to_certified(struct sshkey *k)
2115 {
2116 int newtype;
2117
2118 if ((newtype = sshkey_type_certified(k->type)) == -1)
2119 return SSH_ERR_INVALID_ARGUMENT;
2120 if ((k->cert = cert_new()) == NULL)
2121 return SSH_ERR_ALLOC_FAIL;
2122 k->type = newtype;
2123 return 0;
2124 }
2125
2126 /* Convert a certificate to its raw key equivalent */
2127 int
sshkey_drop_cert(struct sshkey * k)2128 sshkey_drop_cert(struct sshkey *k)
2129 {
2130 if (!sshkey_type_is_cert(k->type))
2131 return SSH_ERR_KEY_TYPE_UNKNOWN;
2132 cert_free(k->cert);
2133 k->cert = NULL;
2134 k->type = sshkey_type_plain(k->type);
2135 return 0;
2136 }
2137
2138 /* Sign a certified key, (re-)generating the signed certblob. */
2139 int
sshkey_certify_custom(struct sshkey * k,struct sshkey * ca,const char * alg,const char * sk_provider,const char * sk_pin,sshkey_certify_signer * signer,void * signer_ctx)2140 sshkey_certify_custom(struct sshkey *k, struct sshkey *ca, const char *alg,
2141 const char *sk_provider, const char *sk_pin,
2142 sshkey_certify_signer *signer, void *signer_ctx)
2143 {
2144 const struct sshkey_impl *impl;
2145 struct sshbuf *principals = NULL;
2146 u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32];
2147 size_t i, ca_len, sig_len;
2148 int ret = SSH_ERR_INTERNAL_ERROR;
2149 struct sshbuf *cert = NULL;
2150 char *sigtype = NULL;
2151
2152 if (k == NULL || k->cert == NULL ||
2153 k->cert->certblob == NULL || ca == NULL)
2154 return SSH_ERR_INVALID_ARGUMENT;
2155 if (!sshkey_is_cert(k))
2156 return SSH_ERR_KEY_TYPE_UNKNOWN;
2157 if (!sshkey_type_is_valid_ca(ca->type))
2158 return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2159 if ((impl = sshkey_impl_from_key(k)) == NULL)
2160 return SSH_ERR_INTERNAL_ERROR;
2161
2162 /*
2163 * If no alg specified as argument but a signature_type was set,
2164 * then prefer that. If both were specified, then they must match.
2165 */
2166 if (alg == NULL)
2167 alg = k->cert->signature_type;
2168 else if (k->cert->signature_type != NULL &&
2169 strcmp(alg, k->cert->signature_type) != 0)
2170 return SSH_ERR_INVALID_ARGUMENT;
2171
2172 /*
2173 * If no signing algorithm or signature_type was specified and we're
2174 * using a RSA key, then default to a good signature algorithm.
2175 */
2176 if (alg == NULL && ca->type == KEY_RSA)
2177 alg = "rsa-sha2-512";
2178
2179 if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0)
2180 return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2181
2182 cert = k->cert->certblob; /* for readability */
2183 sshbuf_reset(cert);
2184 if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0)
2185 goto out;
2186
2187 /* -v01 certs put nonce first */
2188 arc4random_buf(&nonce, sizeof(nonce));
2189 if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0)
2190 goto out;
2191
2192 /* Public key next */
2193 if ((ret = impl->funcs->serialize_public(k, cert,
2194 SSHKEY_SERIALIZE_DEFAULT)) != 0)
2195 goto out;
2196
2197 /* Then remaining cert fields */
2198 if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 ||
2199 (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 ||
2200 (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0)
2201 goto out;
2202
2203 if ((principals = sshbuf_new()) == NULL) {
2204 ret = SSH_ERR_ALLOC_FAIL;
2205 goto out;
2206 }
2207 for (i = 0; i < k->cert->nprincipals; i++) {
2208 if ((ret = sshbuf_put_cstring(principals,
2209 k->cert->principals[i])) != 0)
2210 goto out;
2211 }
2212 if ((ret = sshbuf_put_stringb(cert, principals)) != 0 ||
2213 (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 ||
2214 (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 ||
2215 (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 ||
2216 (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 ||
2217 (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */
2218 (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0)
2219 goto out;
2220
2221 /* Sign the whole mess */
2222 if ((ret = signer(ca, &sig_blob, &sig_len, sshbuf_ptr(cert),
2223 sshbuf_len(cert), alg, sk_provider, sk_pin, 0, signer_ctx)) != 0)
2224 goto out;
2225 /* Check and update signature_type against what was actually used */
2226 if ((ret = sshkey_get_sigtype(sig_blob, sig_len, &sigtype)) != 0)
2227 goto out;
2228 if (alg != NULL && strcmp(alg, sigtype) != 0) {
2229 ret = SSH_ERR_SIGN_ALG_UNSUPPORTED;
2230 goto out;
2231 }
2232 if (k->cert->signature_type == NULL) {
2233 k->cert->signature_type = sigtype;
2234 sigtype = NULL;
2235 }
2236 /* Append signature and we are done */
2237 if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0)
2238 goto out;
2239 ret = 0;
2240 out:
2241 if (ret != 0)
2242 sshbuf_reset(cert);
2243 free(sig_blob);
2244 free(ca_blob);
2245 free(sigtype);
2246 sshbuf_free(principals);
2247 return ret;
2248 }
2249
2250 static int
default_key_sign(struct sshkey * key,u_char ** sigp,size_t * lenp,const u_char * data,size_t datalen,const char * alg,const char * sk_provider,const char * sk_pin,u_int compat,void * ctx)2251 default_key_sign(struct sshkey *key, u_char **sigp, size_t *lenp,
2252 const u_char *data, size_t datalen,
2253 const char *alg, const char *sk_provider, const char *sk_pin,
2254 u_int compat, void *ctx)
2255 {
2256 if (ctx != NULL)
2257 return SSH_ERR_INVALID_ARGUMENT;
2258 return sshkey_sign(key, sigp, lenp, data, datalen, alg,
2259 sk_provider, sk_pin, compat);
2260 }
2261
2262 int
sshkey_certify(struct sshkey * k,struct sshkey * ca,const char * alg,const char * sk_provider,const char * sk_pin)2263 sshkey_certify(struct sshkey *k, struct sshkey *ca, const char *alg,
2264 const char *sk_provider, const char *sk_pin)
2265 {
2266 return sshkey_certify_custom(k, ca, alg, sk_provider, sk_pin,
2267 default_key_sign, NULL);
2268 }
2269
2270 int
sshkey_cert_check_authority(const struct sshkey * k,int want_host,int require_principal,int wildcard_pattern,uint64_t verify_time,const char * name,const char ** reason)2271 sshkey_cert_check_authority(const struct sshkey *k,
2272 int want_host, int require_principal, int wildcard_pattern,
2273 uint64_t verify_time, const char *name, const char **reason)
2274 {
2275 u_int i, principal_matches;
2276
2277 if (reason == NULL)
2278 return SSH_ERR_INVALID_ARGUMENT;
2279 if (!sshkey_is_cert(k)) {
2280 *reason = "Key is not a certificate";
2281 return SSH_ERR_KEY_CERT_INVALID;
2282 }
2283 if (want_host) {
2284 if (k->cert->type != SSH2_CERT_TYPE_HOST) {
2285 *reason = "Certificate invalid: not a host certificate";
2286 return SSH_ERR_KEY_CERT_INVALID;
2287 }
2288 } else {
2289 if (k->cert->type != SSH2_CERT_TYPE_USER) {
2290 *reason = "Certificate invalid: not a user certificate";
2291 return SSH_ERR_KEY_CERT_INVALID;
2292 }
2293 }
2294 if (verify_time < k->cert->valid_after) {
2295 *reason = "Certificate invalid: not yet valid";
2296 return SSH_ERR_KEY_CERT_INVALID;
2297 }
2298 if (verify_time >= k->cert->valid_before) {
2299 *reason = "Certificate invalid: expired";
2300 return SSH_ERR_KEY_CERT_INVALID;
2301 }
2302 if (k->cert->nprincipals == 0) {
2303 if (require_principal) {
2304 *reason = "Certificate lacks principal list";
2305 return SSH_ERR_KEY_CERT_INVALID;
2306 }
2307 } else if (name != NULL) {
2308 principal_matches = 0;
2309 for (i = 0; i < k->cert->nprincipals; i++) {
2310 if (wildcard_pattern) {
2311 if (match_pattern(k->cert->principals[i],
2312 name)) {
2313 principal_matches = 1;
2314 break;
2315 }
2316 } else if (strcmp(name, k->cert->principals[i]) == 0) {
2317 principal_matches = 1;
2318 break;
2319 }
2320 }
2321 if (!principal_matches) {
2322 *reason = "Certificate invalid: name is not a listed "
2323 "principal";
2324 return SSH_ERR_KEY_CERT_INVALID;
2325 }
2326 }
2327 return 0;
2328 }
2329
2330 int
sshkey_cert_check_authority_now(const struct sshkey * k,int want_host,int require_principal,int wildcard_pattern,const char * name,const char ** reason)2331 sshkey_cert_check_authority_now(const struct sshkey *k,
2332 int want_host, int require_principal, int wildcard_pattern,
2333 const char *name, const char **reason)
2334 {
2335 time_t now;
2336
2337 if ((now = time(NULL)) < 0) {
2338 /* yikes - system clock before epoch! */
2339 *reason = "Certificate invalid: not yet valid";
2340 return SSH_ERR_KEY_CERT_INVALID;
2341 }
2342 return sshkey_cert_check_authority(k, want_host, require_principal,
2343 wildcard_pattern, (uint64_t)now, name, reason);
2344 }
2345
2346 int
sshkey_cert_check_host(const struct sshkey * key,const char * host,int wildcard_principals,const char * ca_sign_algorithms,const char ** reason)2347 sshkey_cert_check_host(const struct sshkey *key, const char *host,
2348 int wildcard_principals, const char *ca_sign_algorithms,
2349 const char **reason)
2350 {
2351 int r;
2352
2353 if ((r = sshkey_cert_check_authority_now(key, 1, 0, wildcard_principals,
2354 host, reason)) != 0)
2355 return r;
2356 if (sshbuf_len(key->cert->critical) != 0) {
2357 *reason = "Certificate contains unsupported critical options";
2358 return SSH_ERR_KEY_CERT_INVALID;
2359 }
2360 if (ca_sign_algorithms != NULL &&
2361 (r = sshkey_check_cert_sigtype(key, ca_sign_algorithms)) != 0) {
2362 *reason = "Certificate signed with disallowed algorithm";
2363 return SSH_ERR_KEY_CERT_INVALID;
2364 }
2365 return 0;
2366 }
2367
2368 size_t
sshkey_format_cert_validity(const struct sshkey_cert * cert,char * s,size_t l)2369 sshkey_format_cert_validity(const struct sshkey_cert *cert, char *s, size_t l)
2370 {
2371 char from[32], to[32], ret[128];
2372
2373 *from = *to = '\0';
2374 if (cert->valid_after == 0 &&
2375 cert->valid_before == 0xffffffffffffffffULL)
2376 return strlcpy(s, "forever", l);
2377
2378 if (cert->valid_after != 0)
2379 format_absolute_time(cert->valid_after, from, sizeof(from));
2380 if (cert->valid_before != 0xffffffffffffffffULL)
2381 format_absolute_time(cert->valid_before, to, sizeof(to));
2382
2383 if (cert->valid_after == 0)
2384 snprintf(ret, sizeof(ret), "before %s", to);
2385 else if (cert->valid_before == 0xffffffffffffffffULL)
2386 snprintf(ret, sizeof(ret), "after %s", from);
2387 else
2388 snprintf(ret, sizeof(ret), "from %s to %s", from, to);
2389
2390 return strlcpy(s, ret, l);
2391 }
2392
2393 /* Common serialization for FIDO private keys */
2394 int
sshkey_serialize_private_sk(const struct sshkey * key,struct sshbuf * b)2395 sshkey_serialize_private_sk(const struct sshkey *key, struct sshbuf *b)
2396 {
2397 int r;
2398
2399 if ((r = sshbuf_put_cstring(b, key->sk_application)) != 0 ||
2400 (r = sshbuf_put_u8(b, key->sk_flags)) != 0 ||
2401 (r = sshbuf_put_stringb(b, key->sk_key_handle)) != 0 ||
2402 (r = sshbuf_put_stringb(b, key->sk_reserved)) != 0)
2403 return r;
2404
2405 return 0;
2406 }
2407
2408 int
sshkey_private_serialize_opt(struct sshkey * key,struct sshbuf * buf,enum sshkey_serialize_rep opts)2409 sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
2410 enum sshkey_serialize_rep opts)
2411 {
2412 int r = SSH_ERR_INTERNAL_ERROR;
2413 int was_shielded = sshkey_is_shielded(key);
2414 struct sshbuf *b = NULL;
2415 const struct sshkey_impl *impl;
2416
2417 if ((impl = sshkey_impl_from_key(key)) == NULL)
2418 return SSH_ERR_INTERNAL_ERROR;
2419 if ((r = sshkey_unshield_private(key)) != 0)
2420 return r;
2421 if ((b = sshbuf_new()) == NULL)
2422 return SSH_ERR_ALLOC_FAIL;
2423 if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0)
2424 goto out;
2425 if (sshkey_is_cert(key)) {
2426 if (key->cert == NULL ||
2427 sshbuf_len(key->cert->certblob) == 0) {
2428 r = SSH_ERR_INVALID_ARGUMENT;
2429 goto out;
2430 }
2431 if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0)
2432 goto out;
2433 }
2434 if ((r = impl->funcs->serialize_private(key, b, opts)) != 0)
2435 goto out;
2436
2437 /*
2438 * success (but we still need to append the output to buf after
2439 * possibly re-shielding the private key)
2440 */
2441 r = 0;
2442 out:
2443 if (was_shielded)
2444 r = sshkey_shield_private(key);
2445 if (r == 0)
2446 r = sshbuf_putb(buf, b);
2447 sshbuf_free(b);
2448
2449 return r;
2450 }
2451
2452 int
sshkey_private_serialize(struct sshkey * key,struct sshbuf * b)2453 sshkey_private_serialize(struct sshkey *key, struct sshbuf *b)
2454 {
2455 return sshkey_private_serialize_opt(key, b,
2456 SSHKEY_SERIALIZE_DEFAULT);
2457 }
2458
2459 /* Shared deserialization of FIDO private key components */
2460 int
sshkey_private_deserialize_sk(struct sshbuf * buf,struct sshkey * k)2461 sshkey_private_deserialize_sk(struct sshbuf *buf, struct sshkey *k)
2462 {
2463 int r;
2464
2465 if ((k->sk_key_handle = sshbuf_new()) == NULL ||
2466 (k->sk_reserved = sshbuf_new()) == NULL)
2467 return SSH_ERR_ALLOC_FAIL;
2468 if ((r = sshbuf_get_cstring(buf, &k->sk_application, NULL)) != 0 ||
2469 (r = sshbuf_get_u8(buf, &k->sk_flags)) != 0 ||
2470 (r = sshbuf_get_stringb(buf, k->sk_key_handle)) != 0 ||
2471 (r = sshbuf_get_stringb(buf, k->sk_reserved)) != 0)
2472 return r;
2473
2474 return 0;
2475 }
2476
2477 int
sshkey_private_deserialize(struct sshbuf * buf,struct sshkey ** kp)2478 sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
2479 {
2480 const struct sshkey_impl *impl;
2481 char *tname = NULL;
2482 char *expect_sk_application = NULL;
2483 u_char *expect_ed25519_pk = NULL;
2484 struct sshkey *k = NULL;
2485 int type, r = SSH_ERR_INTERNAL_ERROR;
2486
2487 if (kp != NULL)
2488 *kp = NULL;
2489 if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0)
2490 goto out;
2491 type = sshkey_type_from_name(tname);
2492 if (sshkey_type_is_cert(type)) {
2493 /*
2494 * Certificate key private keys begin with the certificate
2495 * itself. Make sure this matches the type of the enclosing
2496 * private key.
2497 */
2498 if ((r = sshkey_froms(buf, &k)) != 0)
2499 goto out;
2500 if (k->type != type) {
2501 r = SSH_ERR_KEY_CERT_MISMATCH;
2502 goto out;
2503 }
2504 /* For ECDSA keys, the group must match too */
2505 if (k->type == KEY_ECDSA &&
2506 k->ecdsa_nid != sshkey_ecdsa_nid_from_name(tname)) {
2507 r = SSH_ERR_KEY_CERT_MISMATCH;
2508 goto out;
2509 }
2510 /*
2511 * Several fields are redundant between certificate and
2512 * private key body, we require these to match.
2513 */
2514 expect_sk_application = k->sk_application;
2515 expect_ed25519_pk = k->ed25519_pk;
2516 k->sk_application = NULL;
2517 k->ed25519_pk = NULL;
2518 /* XXX xmss too or refactor */
2519 } else {
2520 if ((k = sshkey_new(type)) == NULL) {
2521 r = SSH_ERR_ALLOC_FAIL;
2522 goto out;
2523 }
2524 }
2525 if ((impl = sshkey_impl_from_type(type)) == NULL) {
2526 r = SSH_ERR_INTERNAL_ERROR;
2527 goto out;
2528 }
2529 if ((r = impl->funcs->deserialize_private(tname, buf, k)) != 0)
2530 goto out;
2531
2532 /* XXX xmss too or refactor */
2533 if ((expect_sk_application != NULL && (k->sk_application == NULL ||
2534 strcmp(expect_sk_application, k->sk_application) != 0)) ||
2535 (expect_ed25519_pk != NULL && (k->ed25519_pk == NULL ||
2536 memcmp(expect_ed25519_pk, k->ed25519_pk, ED25519_PK_SZ) != 0))) {
2537 r = SSH_ERR_KEY_CERT_MISMATCH;
2538 goto out;
2539 }
2540 /* success */
2541 r = 0;
2542 if (kp != NULL) {
2543 *kp = k;
2544 k = NULL;
2545 }
2546 out:
2547 free(tname);
2548 sshkey_free(k);
2549 free(expect_sk_application);
2550 free(expect_ed25519_pk);
2551 return r;
2552 }
2553
2554 #ifdef WITH_OPENSSL
2555 int
sshkey_ec_validate_public(const EC_GROUP * group,const EC_POINT * public)2556 sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
2557 {
2558 EC_POINT *nq = NULL;
2559 BIGNUM *order = NULL, *x = NULL, *y = NULL, *tmp = NULL;
2560 int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2561
2562 /*
2563 * NB. This assumes OpenSSL has already verified that the public
2564 * point lies on the curve. This is done by EC_POINT_oct2point()
2565 * implicitly calling EC_POINT_is_on_curve(). If this code is ever
2566 * reachable with public points not unmarshalled using
2567 * EC_POINT_oct2point then the caller will need to explicitly check.
2568 */
2569
2570 /*
2571 * We shouldn't ever hit this case because bignum_get_ecpoint()
2572 * refuses to load GF2m points.
2573 */
2574 if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2575 NID_X9_62_prime_field)
2576 goto out;
2577
2578 /* Q != infinity */
2579 if (EC_POINT_is_at_infinity(group, public))
2580 goto out;
2581
2582 if ((x = BN_new()) == NULL ||
2583 (y = BN_new()) == NULL ||
2584 (order = BN_new()) == NULL ||
2585 (tmp = BN_new()) == NULL) {
2586 ret = SSH_ERR_ALLOC_FAIL;
2587 goto out;
2588 }
2589
2590 /* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
2591 if (EC_GROUP_get_order(group, order, NULL) != 1 ||
2592 EC_POINT_get_affine_coordinates_GFp(group, public,
2593 x, y, NULL) != 1) {
2594 ret = SSH_ERR_LIBCRYPTO_ERROR;
2595 goto out;
2596 }
2597 if (BN_num_bits(x) <= BN_num_bits(order) / 2 ||
2598 BN_num_bits(y) <= BN_num_bits(order) / 2)
2599 goto out;
2600
2601 /* nQ == infinity (n == order of subgroup) */
2602 if ((nq = EC_POINT_new(group)) == NULL) {
2603 ret = SSH_ERR_ALLOC_FAIL;
2604 goto out;
2605 }
2606 if (EC_POINT_mul(group, nq, NULL, public, order, NULL) != 1) {
2607 ret = SSH_ERR_LIBCRYPTO_ERROR;
2608 goto out;
2609 }
2610 if (EC_POINT_is_at_infinity(group, nq) != 1)
2611 goto out;
2612
2613 /* x < order - 1, y < order - 1 */
2614 if (!BN_sub(tmp, order, BN_value_one())) {
2615 ret = SSH_ERR_LIBCRYPTO_ERROR;
2616 goto out;
2617 }
2618 if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0)
2619 goto out;
2620 ret = 0;
2621 out:
2622 BN_clear_free(x);
2623 BN_clear_free(y);
2624 BN_clear_free(order);
2625 BN_clear_free(tmp);
2626 EC_POINT_free(nq);
2627 return ret;
2628 }
2629
2630 int
sshkey_ec_validate_private(const EC_KEY * key)2631 sshkey_ec_validate_private(const EC_KEY *key)
2632 {
2633 BIGNUM *order = NULL, *tmp = NULL;
2634 int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2635
2636 if ((order = BN_new()) == NULL || (tmp = BN_new()) == NULL) {
2637 ret = SSH_ERR_ALLOC_FAIL;
2638 goto out;
2639 }
2640
2641 /* log2(private) > log2(order)/2 */
2642 if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, NULL) != 1) {
2643 ret = SSH_ERR_LIBCRYPTO_ERROR;
2644 goto out;
2645 }
2646 if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
2647 BN_num_bits(order) / 2)
2648 goto out;
2649
2650 /* private < order - 1 */
2651 if (!BN_sub(tmp, order, BN_value_one())) {
2652 ret = SSH_ERR_LIBCRYPTO_ERROR;
2653 goto out;
2654 }
2655 if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0)
2656 goto out;
2657 ret = 0;
2658 out:
2659 BN_clear_free(order);
2660 BN_clear_free(tmp);
2661 return ret;
2662 }
2663
2664 void
sshkey_dump_ec_point(const EC_GROUP * group,const EC_POINT * point)2665 sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
2666 {
2667 BIGNUM *x = NULL, *y = NULL;
2668
2669 if (point == NULL) {
2670 fputs("point=(NULL)\n", stderr);
2671 return;
2672 }
2673 if ((x = BN_new()) == NULL || (y = BN_new()) == NULL) {
2674 fprintf(stderr, "%s: BN_new failed\n", __func__);
2675 goto out;
2676 }
2677 if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2678 NID_X9_62_prime_field) {
2679 fprintf(stderr, "%s: group is not a prime field\n", __func__);
2680 goto out;
2681 }
2682 if (EC_POINT_get_affine_coordinates_GFp(group, point,
2683 x, y, NULL) != 1) {
2684 fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n",
2685 __func__);
2686 goto out;
2687 }
2688 fputs("x=", stderr);
2689 BN_print_fp(stderr, x);
2690 fputs("\ny=", stderr);
2691 BN_print_fp(stderr, y);
2692 fputs("\n", stderr);
2693 out:
2694 BN_clear_free(x);
2695 BN_clear_free(y);
2696 }
2697
2698 void
sshkey_dump_ec_key(const EC_KEY * key)2699 sshkey_dump_ec_key(const EC_KEY *key)
2700 {
2701 const BIGNUM *exponent;
2702
2703 sshkey_dump_ec_point(EC_KEY_get0_group(key),
2704 EC_KEY_get0_public_key(key));
2705 fputs("exponent=", stderr);
2706 if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
2707 fputs("(NULL)", stderr);
2708 else
2709 BN_print_fp(stderr, EC_KEY_get0_private_key(key));
2710 fputs("\n", stderr);
2711 }
2712 #endif /* WITH_OPENSSL */
2713
2714 static int
sshkey_private_to_blob2(struct sshkey * prv,struct sshbuf * blob,const char * passphrase,const char * comment,const char * ciphername,int rounds)2715 sshkey_private_to_blob2(struct sshkey *prv, struct sshbuf *blob,
2716 const char *passphrase, const char *comment, const char *ciphername,
2717 int rounds)
2718 {
2719 u_char *cp, *key = NULL, *pubkeyblob = NULL;
2720 u_char salt[SALT_LEN];
2721 size_t i, pubkeylen, keylen, ivlen, blocksize, authlen;
2722 u_int check;
2723 int r = SSH_ERR_INTERNAL_ERROR;
2724 struct sshcipher_ctx *ciphercontext = NULL;
2725 const struct sshcipher *cipher;
2726 const char *kdfname = KDFNAME;
2727 struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL;
2728
2729 if (rounds <= 0)
2730 rounds = DEFAULT_ROUNDS;
2731 if (passphrase == NULL || !strlen(passphrase)) {
2732 ciphername = "none";
2733 kdfname = "none";
2734 } else if (ciphername == NULL)
2735 ciphername = DEFAULT_CIPHERNAME;
2736 if ((cipher = cipher_by_name(ciphername)) == NULL) {
2737 r = SSH_ERR_INVALID_ARGUMENT;
2738 goto out;
2739 }
2740
2741 if ((kdf = sshbuf_new()) == NULL ||
2742 (encoded = sshbuf_new()) == NULL ||
2743 (encrypted = sshbuf_new()) == NULL) {
2744 r = SSH_ERR_ALLOC_FAIL;
2745 goto out;
2746 }
2747 blocksize = cipher_blocksize(cipher);
2748 keylen = cipher_keylen(cipher);
2749 ivlen = cipher_ivlen(cipher);
2750 authlen = cipher_authlen(cipher);
2751 if ((key = calloc(1, keylen + ivlen)) == NULL) {
2752 r = SSH_ERR_ALLOC_FAIL;
2753 goto out;
2754 }
2755 if (strcmp(kdfname, "bcrypt") == 0) {
2756 arc4random_buf(salt, SALT_LEN);
2757 if (bcrypt_pbkdf(passphrase, strlen(passphrase),
2758 salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) {
2759 r = SSH_ERR_INVALID_ARGUMENT;
2760 goto out;
2761 }
2762 if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 ||
2763 (r = sshbuf_put_u32(kdf, rounds)) != 0)
2764 goto out;
2765 } else if (strcmp(kdfname, "none") != 0) {
2766 /* Unsupported KDF type */
2767 r = SSH_ERR_KEY_UNKNOWN_CIPHER;
2768 goto out;
2769 }
2770 if ((r = cipher_init(&ciphercontext, cipher, key, keylen,
2771 key + keylen, ivlen, 1)) != 0)
2772 goto out;
2773
2774 if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 ||
2775 (r = sshbuf_put_cstring(encoded, ciphername)) != 0 ||
2776 (r = sshbuf_put_cstring(encoded, kdfname)) != 0 ||
2777 (r = sshbuf_put_stringb(encoded, kdf)) != 0 ||
2778 (r = sshbuf_put_u32(encoded, 1)) != 0 || /* number of keys */
2779 (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 ||
2780 (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0)
2781 goto out;
2782
2783 /* set up the buffer that will be encrypted */
2784
2785 /* Random check bytes */
2786 check = arc4random();
2787 if ((r = sshbuf_put_u32(encrypted, check)) != 0 ||
2788 (r = sshbuf_put_u32(encrypted, check)) != 0)
2789 goto out;
2790
2791 /* append private key and comment*/
2792 if ((r = sshkey_private_serialize_opt(prv, encrypted,
2793 SSHKEY_SERIALIZE_FULL)) != 0 ||
2794 (r = sshbuf_put_cstring(encrypted, comment)) != 0)
2795 goto out;
2796
2797 /* padding */
2798 i = 0;
2799 while (sshbuf_len(encrypted) % blocksize) {
2800 if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0)
2801 goto out;
2802 }
2803
2804 /* length in destination buffer */
2805 if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0)
2806 goto out;
2807
2808 /* encrypt */
2809 if ((r = sshbuf_reserve(encoded,
2810 sshbuf_len(encrypted) + authlen, &cp)) != 0)
2811 goto out;
2812 if ((r = cipher_crypt(ciphercontext, 0, cp,
2813 sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0)
2814 goto out;
2815
2816 sshbuf_reset(blob);
2817
2818 /* assemble uuencoded key */
2819 if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0 ||
2820 (r = sshbuf_dtob64(encoded, blob, 1)) != 0 ||
2821 (r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0)
2822 goto out;
2823
2824 /* success */
2825 r = 0;
2826
2827 out:
2828 sshbuf_free(kdf);
2829 sshbuf_free(encoded);
2830 sshbuf_free(encrypted);
2831 cipher_free(ciphercontext);
2832 explicit_bzero(salt, sizeof(salt));
2833 if (key != NULL)
2834 freezero(key, keylen + ivlen);
2835 if (pubkeyblob != NULL)
2836 freezero(pubkeyblob, pubkeylen);
2837 return r;
2838 }
2839
2840 static int
private2_uudecode(struct sshbuf * blob,struct sshbuf ** decodedp)2841 private2_uudecode(struct sshbuf *blob, struct sshbuf **decodedp)
2842 {
2843 const u_char *cp;
2844 size_t encoded_len;
2845 int r;
2846 u_char last;
2847 struct sshbuf *encoded = NULL, *decoded = NULL;
2848
2849 if (blob == NULL || decodedp == NULL)
2850 return SSH_ERR_INVALID_ARGUMENT;
2851
2852 *decodedp = NULL;
2853
2854 if ((encoded = sshbuf_new()) == NULL ||
2855 (decoded = sshbuf_new()) == NULL) {
2856 r = SSH_ERR_ALLOC_FAIL;
2857 goto out;
2858 }
2859
2860 /* check preamble */
2861 cp = sshbuf_ptr(blob);
2862 encoded_len = sshbuf_len(blob);
2863 if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) ||
2864 memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) {
2865 r = SSH_ERR_INVALID_FORMAT;
2866 goto out;
2867 }
2868 cp += MARK_BEGIN_LEN;
2869 encoded_len -= MARK_BEGIN_LEN;
2870
2871 /* Look for end marker, removing whitespace as we go */
2872 while (encoded_len > 0) {
2873 if (*cp != '\n' && *cp != '\r') {
2874 if ((r = sshbuf_put_u8(encoded, *cp)) != 0)
2875 goto out;
2876 }
2877 last = *cp;
2878 encoded_len--;
2879 cp++;
2880 if (last == '\n') {
2881 if (encoded_len >= MARK_END_LEN &&
2882 memcmp(cp, MARK_END, MARK_END_LEN) == 0) {
2883 /* \0 terminate */
2884 if ((r = sshbuf_put_u8(encoded, 0)) != 0)
2885 goto out;
2886 break;
2887 }
2888 }
2889 }
2890 if (encoded_len == 0) {
2891 r = SSH_ERR_INVALID_FORMAT;
2892 goto out;
2893 }
2894
2895 /* decode base64 */
2896 if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0)
2897 goto out;
2898
2899 /* check magic */
2900 if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) ||
2901 memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) {
2902 r = SSH_ERR_INVALID_FORMAT;
2903 goto out;
2904 }
2905 /* success */
2906 *decodedp = decoded;
2907 decoded = NULL;
2908 r = 0;
2909 out:
2910 sshbuf_free(encoded);
2911 sshbuf_free(decoded);
2912 return r;
2913 }
2914
2915 static int
private2_decrypt(struct sshbuf * decoded,const char * passphrase,struct sshbuf ** decryptedp,struct sshkey ** pubkeyp)2916 private2_decrypt(struct sshbuf *decoded, const char *passphrase,
2917 struct sshbuf **decryptedp, struct sshkey **pubkeyp)
2918 {
2919 char *ciphername = NULL, *kdfname = NULL;
2920 const struct sshcipher *cipher = NULL;
2921 int r = SSH_ERR_INTERNAL_ERROR;
2922 size_t keylen = 0, ivlen = 0, authlen = 0, slen = 0;
2923 struct sshbuf *kdf = NULL, *decrypted = NULL;
2924 struct sshcipher_ctx *ciphercontext = NULL;
2925 struct sshkey *pubkey = NULL;
2926 u_char *key = NULL, *salt = NULL, *dp;
2927 u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
2928
2929 if (decoded == NULL || decryptedp == NULL || pubkeyp == NULL)
2930 return SSH_ERR_INVALID_ARGUMENT;
2931
2932 *decryptedp = NULL;
2933 *pubkeyp = NULL;
2934
2935 if ((decrypted = sshbuf_new()) == NULL) {
2936 r = SSH_ERR_ALLOC_FAIL;
2937 goto out;
2938 }
2939
2940 /* parse public portion of key */
2941 if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
2942 (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 ||
2943 (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 ||
2944 (r = sshbuf_froms(decoded, &kdf)) != 0 ||
2945 (r = sshbuf_get_u32(decoded, &nkeys)) != 0)
2946 goto out;
2947
2948 if (nkeys != 1) {
2949 /* XXX only one key supported at present */
2950 r = SSH_ERR_INVALID_FORMAT;
2951 goto out;
2952 }
2953
2954 if ((r = sshkey_froms(decoded, &pubkey)) != 0 ||
2955 (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0)
2956 goto out;
2957
2958 if ((cipher = cipher_by_name(ciphername)) == NULL) {
2959 r = SSH_ERR_KEY_UNKNOWN_CIPHER;
2960 goto out;
2961 }
2962 if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) {
2963 r = SSH_ERR_KEY_UNKNOWN_CIPHER;
2964 goto out;
2965 }
2966 if (strcmp(kdfname, "none") == 0 && strcmp(ciphername, "none") != 0) {
2967 r = SSH_ERR_INVALID_FORMAT;
2968 goto out;
2969 }
2970 if ((passphrase == NULL || strlen(passphrase) == 0) &&
2971 strcmp(kdfname, "none") != 0) {
2972 /* passphrase required */
2973 r = SSH_ERR_KEY_WRONG_PASSPHRASE;
2974 goto out;
2975 }
2976
2977 /* check size of encrypted key blob */
2978 blocksize = cipher_blocksize(cipher);
2979 if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) {
2980 r = SSH_ERR_INVALID_FORMAT;
2981 goto out;
2982 }
2983
2984 /* setup key */
2985 keylen = cipher_keylen(cipher);
2986 ivlen = cipher_ivlen(cipher);
2987 authlen = cipher_authlen(cipher);
2988 if ((key = calloc(1, keylen + ivlen)) == NULL) {
2989 r = SSH_ERR_ALLOC_FAIL;
2990 goto out;
2991 }
2992 if (strcmp(kdfname, "bcrypt") == 0) {
2993 if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
2994 (r = sshbuf_get_u32(kdf, &rounds)) != 0)
2995 goto out;
2996 if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
2997 key, keylen + ivlen, rounds) < 0) {
2998 r = SSH_ERR_INVALID_FORMAT;
2999 goto out;
3000 }
3001 }
3002
3003 /* check that an appropriate amount of auth data is present */
3004 if (sshbuf_len(decoded) < authlen ||
3005 sshbuf_len(decoded) - authlen < encrypted_len) {
3006 r = SSH_ERR_INVALID_FORMAT;
3007 goto out;
3008 }
3009
3010 /* decrypt private portion of key */
3011 if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 ||
3012 (r = cipher_init(&ciphercontext, cipher, key, keylen,
3013 key + keylen, ivlen, 0)) != 0)
3014 goto out;
3015 if ((r = cipher_crypt(ciphercontext, 0, dp, sshbuf_ptr(decoded),
3016 encrypted_len, 0, authlen)) != 0) {
3017 /* an integrity error here indicates an incorrect passphrase */
3018 if (r == SSH_ERR_MAC_INVALID)
3019 r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3020 goto out;
3021 }
3022 if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0)
3023 goto out;
3024 /* there should be no trailing data */
3025 if (sshbuf_len(decoded) != 0) {
3026 r = SSH_ERR_INVALID_FORMAT;
3027 goto out;
3028 }
3029
3030 /* check check bytes */
3031 if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 ||
3032 (r = sshbuf_get_u32(decrypted, &check2)) != 0)
3033 goto out;
3034 if (check1 != check2) {
3035 r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3036 goto out;
3037 }
3038 /* success */
3039 *decryptedp = decrypted;
3040 decrypted = NULL;
3041 *pubkeyp = pubkey;
3042 pubkey = NULL;
3043 r = 0;
3044 out:
3045 cipher_free(ciphercontext);
3046 free(ciphername);
3047 free(kdfname);
3048 sshkey_free(pubkey);
3049 if (salt != NULL) {
3050 explicit_bzero(salt, slen);
3051 free(salt);
3052 }
3053 if (key != NULL) {
3054 explicit_bzero(key, keylen + ivlen);
3055 free(key);
3056 }
3057 sshbuf_free(kdf);
3058 sshbuf_free(decrypted);
3059 return r;
3060 }
3061
3062 static int
sshkey_parse_private2(struct sshbuf * blob,int type,const char * passphrase,struct sshkey ** keyp,char ** commentp)3063 sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase,
3064 struct sshkey **keyp, char **commentp)
3065 {
3066 char *comment = NULL;
3067 int r = SSH_ERR_INTERNAL_ERROR;
3068 struct sshbuf *decoded = NULL, *decrypted = NULL;
3069 struct sshkey *k = NULL, *pubkey = NULL;
3070
3071 if (keyp != NULL)
3072 *keyp = NULL;
3073 if (commentp != NULL)
3074 *commentp = NULL;
3075
3076 /* Undo base64 encoding and decrypt the private section */
3077 if ((r = private2_uudecode(blob, &decoded)) != 0 ||
3078 (r = private2_decrypt(decoded, passphrase,
3079 &decrypted, &pubkey)) != 0)
3080 goto out;
3081
3082 if (type != KEY_UNSPEC &&
3083 sshkey_type_plain(type) != sshkey_type_plain(pubkey->type)) {
3084 r = SSH_ERR_KEY_TYPE_MISMATCH;
3085 goto out;
3086 }
3087
3088 /* Load the private key and comment */
3089 if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 ||
3090 (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0)
3091 goto out;
3092
3093 /* Check deterministic padding after private section */
3094 if ((r = private2_check_padding(decrypted)) != 0)
3095 goto out;
3096
3097 /* Check that the public key in the envelope matches the private key */
3098 if (!sshkey_equal(pubkey, k)) {
3099 r = SSH_ERR_INVALID_FORMAT;
3100 goto out;
3101 }
3102
3103 /* success */
3104 r = 0;
3105 if (keyp != NULL) {
3106 *keyp = k;
3107 k = NULL;
3108 }
3109 if (commentp != NULL) {
3110 *commentp = comment;
3111 comment = NULL;
3112 }
3113 out:
3114 free(comment);
3115 sshbuf_free(decoded);
3116 sshbuf_free(decrypted);
3117 sshkey_free(k);
3118 sshkey_free(pubkey);
3119 return r;
3120 }
3121
3122 static int
sshkey_parse_private2_pubkey(struct sshbuf * blob,int type,struct sshkey ** keyp)3123 sshkey_parse_private2_pubkey(struct sshbuf *blob, int type,
3124 struct sshkey **keyp)
3125 {
3126 int r = SSH_ERR_INTERNAL_ERROR;
3127 struct sshbuf *decoded = NULL;
3128 struct sshkey *pubkey = NULL;
3129 u_int nkeys = 0;
3130
3131 if (keyp != NULL)
3132 *keyp = NULL;
3133
3134 if ((r = private2_uudecode(blob, &decoded)) != 0)
3135 goto out;
3136 /* parse public key from unencrypted envelope */
3137 if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
3138 (r = sshbuf_skip_string(decoded)) != 0 || /* cipher */
3139 (r = sshbuf_skip_string(decoded)) != 0 || /* KDF alg */
3140 (r = sshbuf_skip_string(decoded)) != 0 || /* KDF hint */
3141 (r = sshbuf_get_u32(decoded, &nkeys)) != 0)
3142 goto out;
3143
3144 if (nkeys != 1) {
3145 /* XXX only one key supported at present */
3146 r = SSH_ERR_INVALID_FORMAT;
3147 goto out;
3148 }
3149
3150 /* Parse the public key */
3151 if ((r = sshkey_froms(decoded, &pubkey)) != 0)
3152 goto out;
3153
3154 if (type != KEY_UNSPEC &&
3155 sshkey_type_plain(type) != sshkey_type_plain(pubkey->type)) {
3156 r = SSH_ERR_KEY_TYPE_MISMATCH;
3157 goto out;
3158 }
3159
3160 /* success */
3161 r = 0;
3162 if (keyp != NULL) {
3163 *keyp = pubkey;
3164 pubkey = NULL;
3165 }
3166 out:
3167 sshbuf_free(decoded);
3168 sshkey_free(pubkey);
3169 return r;
3170 }
3171
3172 #ifdef WITH_OPENSSL
3173 /* convert SSH v2 key to PEM or PKCS#8 format */
3174 static int
sshkey_private_to_blob_pem_pkcs8(struct sshkey * key,struct sshbuf * buf,int format,const char * _passphrase,const char * comment)3175 sshkey_private_to_blob_pem_pkcs8(struct sshkey *key, struct sshbuf *buf,
3176 int format, const char *_passphrase, const char *comment)
3177 {
3178 int was_shielded = sshkey_is_shielded(key);
3179 int success, r;
3180 int blen, len = strlen(_passphrase);
3181 u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
3182 const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
3183 char *bptr;
3184 BIO *bio = NULL;
3185 struct sshbuf *blob;
3186 EVP_PKEY *pkey = NULL;
3187
3188 if (len > 0 && len <= 4)
3189 return SSH_ERR_PASSPHRASE_TOO_SHORT;
3190 if ((blob = sshbuf_new()) == NULL)
3191 return SSH_ERR_ALLOC_FAIL;
3192 if ((bio = BIO_new(BIO_s_mem())) == NULL) {
3193 r = SSH_ERR_ALLOC_FAIL;
3194 goto out;
3195 }
3196 if (format == SSHKEY_PRIVATE_PKCS8 && (pkey = EVP_PKEY_new()) == NULL) {
3197 r = SSH_ERR_ALLOC_FAIL;
3198 goto out;
3199 }
3200 if ((r = sshkey_unshield_private(key)) != 0)
3201 goto out;
3202
3203 switch (key->type) {
3204 #ifdef WITH_DSA
3205 case KEY_DSA:
3206 if (format == SSHKEY_PRIVATE_PEM) {
3207 success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
3208 cipher, passphrase, len, NULL, NULL);
3209 } else {
3210 success = EVP_PKEY_set1_DSA(pkey, key->dsa);
3211 }
3212 break;
3213 #endif
3214 case KEY_ECDSA:
3215 if (format == SSHKEY_PRIVATE_PEM) {
3216 success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
3217 cipher, passphrase, len, NULL, NULL);
3218 } else {
3219 success = EVP_PKEY_set1_EC_KEY(pkey, key->ecdsa);
3220 }
3221 break;
3222 case KEY_RSA:
3223 if (format == SSHKEY_PRIVATE_PEM) {
3224 success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
3225 cipher, passphrase, len, NULL, NULL);
3226 } else {
3227 success = EVP_PKEY_set1_RSA(pkey, key->rsa);
3228 }
3229 break;
3230 default:
3231 success = 0;
3232 break;
3233 }
3234 if (success == 0) {
3235 r = SSH_ERR_LIBCRYPTO_ERROR;
3236 goto out;
3237 }
3238 if (format == SSHKEY_PRIVATE_PKCS8) {
3239 if ((success = PEM_write_bio_PrivateKey(bio, pkey, cipher,
3240 passphrase, len, NULL, NULL)) == 0) {
3241 r = SSH_ERR_LIBCRYPTO_ERROR;
3242 goto out;
3243 }
3244 }
3245 if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) {
3246 r = SSH_ERR_INTERNAL_ERROR;
3247 goto out;
3248 }
3249 if ((r = sshbuf_put(blob, bptr, blen)) != 0)
3250 goto out;
3251 r = 0;
3252 out:
3253 if (was_shielded)
3254 r = sshkey_shield_private(key);
3255 if (r == 0)
3256 r = sshbuf_putb(buf, blob);
3257
3258 EVP_PKEY_free(pkey);
3259 sshbuf_free(blob);
3260 BIO_free(bio);
3261 return r;
3262 }
3263 #endif /* WITH_OPENSSL */
3264
3265 /* Serialise "key" to buffer "blob" */
3266 int
sshkey_private_to_fileblob(struct sshkey * key,struct sshbuf * blob,const char * passphrase,const char * comment,int format,const char * openssh_format_cipher,int openssh_format_rounds)3267 sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
3268 const char *passphrase, const char *comment,
3269 int format, const char *openssh_format_cipher, int openssh_format_rounds)
3270 {
3271 switch (key->type) {
3272 #ifdef WITH_OPENSSL
3273 case KEY_DSA:
3274 case KEY_ECDSA:
3275 case KEY_RSA:
3276 break; /* see below */
3277 #endif /* WITH_OPENSSL */
3278 case KEY_ED25519:
3279 case KEY_ED25519_SK:
3280 #ifdef WITH_XMSS
3281 case KEY_XMSS:
3282 #endif /* WITH_XMSS */
3283 #ifdef WITH_OPENSSL
3284 case KEY_ECDSA_SK:
3285 #endif /* WITH_OPENSSL */
3286 return sshkey_private_to_blob2(key, blob, passphrase,
3287 comment, openssh_format_cipher, openssh_format_rounds);
3288 default:
3289 return SSH_ERR_KEY_TYPE_UNKNOWN;
3290 }
3291
3292 #ifdef WITH_OPENSSL
3293 switch (format) {
3294 case SSHKEY_PRIVATE_OPENSSH:
3295 return sshkey_private_to_blob2(key, blob, passphrase,
3296 comment, openssh_format_cipher, openssh_format_rounds);
3297 case SSHKEY_PRIVATE_PEM:
3298 case SSHKEY_PRIVATE_PKCS8:
3299 return sshkey_private_to_blob_pem_pkcs8(key, blob,
3300 format, passphrase, comment);
3301 default:
3302 return SSH_ERR_INVALID_ARGUMENT;
3303 }
3304 #endif /* WITH_OPENSSL */
3305 }
3306
3307 #ifdef WITH_OPENSSL
3308 static int
translate_libcrypto_error(unsigned long pem_err)3309 translate_libcrypto_error(unsigned long pem_err)
3310 {
3311 int pem_reason = ERR_GET_REASON(pem_err);
3312
3313 switch (ERR_GET_LIB(pem_err)) {
3314 case ERR_LIB_PEM:
3315 switch (pem_reason) {
3316 case PEM_R_BAD_PASSWORD_READ:
3317 case PEM_R_PROBLEMS_GETTING_PASSWORD:
3318 case PEM_R_BAD_DECRYPT:
3319 return SSH_ERR_KEY_WRONG_PASSPHRASE;
3320 default:
3321 return SSH_ERR_INVALID_FORMAT;
3322 }
3323 case ERR_LIB_EVP:
3324 switch (pem_reason) {
3325 case EVP_R_BAD_DECRYPT:
3326 return SSH_ERR_KEY_WRONG_PASSPHRASE;
3327 #ifdef EVP_R_BN_DECODE_ERROR
3328 case EVP_R_BN_DECODE_ERROR:
3329 #endif
3330 case EVP_R_DECODE_ERROR:
3331 #ifdef EVP_R_PRIVATE_KEY_DECODE_ERROR
3332 case EVP_R_PRIVATE_KEY_DECODE_ERROR:
3333 #endif
3334 return SSH_ERR_INVALID_FORMAT;
3335 default:
3336 return SSH_ERR_LIBCRYPTO_ERROR;
3337 }
3338 case ERR_LIB_ASN1:
3339 return SSH_ERR_INVALID_FORMAT;
3340 }
3341 return SSH_ERR_LIBCRYPTO_ERROR;
3342 }
3343
3344 static void
clear_libcrypto_errors(void)3345 clear_libcrypto_errors(void)
3346 {
3347 while (ERR_get_error() != 0)
3348 ;
3349 }
3350
3351 /*
3352 * Translate OpenSSL error codes to determine whether
3353 * passphrase is required/incorrect.
3354 */
3355 static int
convert_libcrypto_error(void)3356 convert_libcrypto_error(void)
3357 {
3358 /*
3359 * Some password errors are reported at the beginning
3360 * of the error queue.
3361 */
3362 if (translate_libcrypto_error(ERR_peek_error()) ==
3363 SSH_ERR_KEY_WRONG_PASSPHRASE)
3364 return SSH_ERR_KEY_WRONG_PASSPHRASE;
3365 return translate_libcrypto_error(ERR_peek_last_error());
3366 }
3367
3368 static int
sshkey_parse_private_pem_fileblob(struct sshbuf * blob,int type,const char * passphrase,struct sshkey ** keyp)3369 sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
3370 const char *passphrase, struct sshkey **keyp)
3371 {
3372 EVP_PKEY *pk = NULL;
3373 struct sshkey *prv = NULL;
3374 BIO *bio = NULL;
3375 int r;
3376
3377 if (keyp != NULL)
3378 *keyp = NULL;
3379
3380 if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
3381 return SSH_ERR_ALLOC_FAIL;
3382 if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) !=
3383 (int)sshbuf_len(blob)) {
3384 r = SSH_ERR_ALLOC_FAIL;
3385 goto out;
3386 }
3387
3388 clear_libcrypto_errors();
3389 if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL,
3390 (char *)passphrase)) == NULL) {
3391 /*
3392 * libcrypto may return various ASN.1 errors when attempting
3393 * to parse a key with an incorrect passphrase.
3394 * Treat all format errors as "incorrect passphrase" if a
3395 * passphrase was supplied.
3396 */
3397 if (passphrase != NULL && *passphrase != '\0')
3398 r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3399 else
3400 r = convert_libcrypto_error();
3401 goto out;
3402 }
3403 if (EVP_PKEY_base_id(pk) == EVP_PKEY_RSA &&
3404 (type == KEY_UNSPEC || type == KEY_RSA)) {
3405 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3406 r = SSH_ERR_ALLOC_FAIL;
3407 goto out;
3408 }
3409 prv->rsa = EVP_PKEY_get1_RSA(pk);
3410 prv->type = KEY_RSA;
3411 #ifdef DEBUG_PK
3412 RSA_print_fp(stderr, prv->rsa, 8);
3413 #endif
3414 if (RSA_blinding_on(prv->rsa, NULL) != 1) {
3415 r = SSH_ERR_LIBCRYPTO_ERROR;
3416 goto out;
3417 }
3418 if ((r = sshkey_check_rsa_length(prv, 0)) != 0)
3419 goto out;
3420 #ifdef WITH_DSA
3421 } else if (EVP_PKEY_base_id(pk) == EVP_PKEY_DSA &&
3422 (type == KEY_UNSPEC || type == KEY_DSA)) {
3423 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3424 r = SSH_ERR_ALLOC_FAIL;
3425 goto out;
3426 }
3427 prv->dsa = EVP_PKEY_get1_DSA(pk);
3428 prv->type = KEY_DSA;
3429 #ifdef DEBUG_PK
3430 DSA_print_fp(stderr, prv->dsa, 8);
3431 #endif
3432 #endif
3433 } else if (EVP_PKEY_base_id(pk) == EVP_PKEY_EC &&
3434 (type == KEY_UNSPEC || type == KEY_ECDSA)) {
3435 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3436 r = SSH_ERR_ALLOC_FAIL;
3437 goto out;
3438 }
3439 prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
3440 prv->type = KEY_ECDSA;
3441 prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa);
3442 if (prv->ecdsa_nid == -1 ||
3443 sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
3444 sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
3445 EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
3446 sshkey_ec_validate_private(prv->ecdsa) != 0) {
3447 r = SSH_ERR_INVALID_FORMAT;
3448 goto out;
3449 }
3450 #ifdef DEBUG_PK
3451 if (prv != NULL && prv->ecdsa != NULL)
3452 sshkey_dump_ec_key(prv->ecdsa);
3453 #endif
3454 } else if (EVP_PKEY_base_id(pk) == EVP_PKEY_ED25519 &&
3455 (type == KEY_UNSPEC || type == KEY_ED25519)) {
3456 size_t len;
3457
3458 if ((prv = sshkey_new(KEY_UNSPEC)) == NULL ||
3459 (prv->ed25519_sk = calloc(1, ED25519_SK_SZ)) == NULL ||
3460 (prv->ed25519_pk = calloc(1, ED25519_PK_SZ)) == NULL) {
3461 r = SSH_ERR_ALLOC_FAIL;
3462 goto out;
3463 }
3464 prv->type = KEY_ED25519;
3465 len = ED25519_PK_SZ;
3466 if (!EVP_PKEY_get_raw_public_key(pk, prv->ed25519_pk, &len)) {
3467 r = SSH_ERR_LIBCRYPTO_ERROR;
3468 goto out;
3469 }
3470 if (len != ED25519_PK_SZ) {
3471 r = SSH_ERR_INVALID_FORMAT;
3472 goto out;
3473 }
3474 len = ED25519_SK_SZ - ED25519_PK_SZ;
3475 if (!EVP_PKEY_get_raw_private_key(pk, prv->ed25519_sk, &len)) {
3476 r = SSH_ERR_LIBCRYPTO_ERROR;
3477 goto out;
3478 }
3479 if (len != ED25519_SK_SZ - ED25519_PK_SZ) {
3480 r = SSH_ERR_INVALID_FORMAT;
3481 goto out;
3482 }
3483 /* Append the public key to our private key */
3484 memcpy(prv->ed25519_sk + (ED25519_SK_SZ - ED25519_PK_SZ),
3485 prv->ed25519_pk, ED25519_PK_SZ);
3486 #ifdef DEBUG_PK
3487 sshbuf_dump_data(prv->ed25519_sk, ED25519_SK_SZ, stderr);
3488 #endif
3489 } else {
3490 r = SSH_ERR_INVALID_FORMAT;
3491 goto out;
3492 }
3493 r = 0;
3494 if (keyp != NULL) {
3495 *keyp = prv;
3496 prv = NULL;
3497 }
3498 out:
3499 BIO_free(bio);
3500 EVP_PKEY_free(pk);
3501 sshkey_free(prv);
3502 return r;
3503 }
3504 #endif /* WITH_OPENSSL */
3505
3506 int
sshkey_parse_private_fileblob_type(struct sshbuf * blob,int type,const char * passphrase,struct sshkey ** keyp,char ** commentp)3507 sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
3508 const char *passphrase, struct sshkey **keyp, char **commentp)
3509 {
3510 int r = SSH_ERR_INTERNAL_ERROR;
3511
3512 if (keyp != NULL)
3513 *keyp = NULL;
3514 if (commentp != NULL)
3515 *commentp = NULL;
3516
3517 switch (type) {
3518 case KEY_XMSS:
3519 /* No fallback for new-format-only keys */
3520 return sshkey_parse_private2(blob, type, passphrase,
3521 keyp, commentp);
3522 default:
3523 r = sshkey_parse_private2(blob, type, passphrase, keyp,
3524 commentp);
3525 /* Only fallback to PEM parser if a format error occurred. */
3526 if (r != SSH_ERR_INVALID_FORMAT)
3527 return r;
3528 #ifdef WITH_OPENSSL
3529 return sshkey_parse_private_pem_fileblob(blob, type,
3530 passphrase, keyp);
3531 #else
3532 return SSH_ERR_INVALID_FORMAT;
3533 #endif /* WITH_OPENSSL */
3534 }
3535 }
3536
3537 int
sshkey_parse_private_fileblob(struct sshbuf * buffer,const char * passphrase,struct sshkey ** keyp,char ** commentp)3538 sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase,
3539 struct sshkey **keyp, char **commentp)
3540 {
3541 if (keyp != NULL)
3542 *keyp = NULL;
3543 if (commentp != NULL)
3544 *commentp = NULL;
3545
3546 return sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
3547 passphrase, keyp, commentp);
3548 }
3549
3550 void
sshkey_sig_details_free(struct sshkey_sig_details * details)3551 sshkey_sig_details_free(struct sshkey_sig_details *details)
3552 {
3553 freezero(details, sizeof(*details));
3554 }
3555
3556 int
sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf * blob,int type,struct sshkey ** pubkeyp)3557 sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob, int type,
3558 struct sshkey **pubkeyp)
3559 {
3560 int r = SSH_ERR_INTERNAL_ERROR;
3561
3562 if (pubkeyp != NULL)
3563 *pubkeyp = NULL;
3564 /* only new-format private keys bundle a public key inside */
3565 if ((r = sshkey_parse_private2_pubkey(blob, type, pubkeyp)) != 0)
3566 return r;
3567 return 0;
3568 }
3569
3570 #ifdef WITH_XMSS
3571 /*
3572 * serialize the key with the current state and forward the state
3573 * maxsign times.
3574 */
3575 int
sshkey_private_serialize_maxsign(struct sshkey * k,struct sshbuf * b,u_int32_t maxsign,int printerror)3576 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b,
3577 u_int32_t maxsign, int printerror)
3578 {
3579 int r, rupdate;
3580
3581 if (maxsign == 0 ||
3582 sshkey_type_plain(k->type) != KEY_XMSS)
3583 return sshkey_private_serialize_opt(k, b,
3584 SSHKEY_SERIALIZE_DEFAULT);
3585 if ((r = sshkey_xmss_get_state(k, printerror)) != 0 ||
3586 (r = sshkey_private_serialize_opt(k, b,
3587 SSHKEY_SERIALIZE_STATE)) != 0 ||
3588 (r = sshkey_xmss_forward_state(k, maxsign)) != 0)
3589 goto out;
3590 r = 0;
3591 out:
3592 if ((rupdate = sshkey_xmss_update_state(k, printerror)) != 0) {
3593 if (r == 0)
3594 r = rupdate;
3595 }
3596 return r;
3597 }
3598
3599 u_int32_t
sshkey_signatures_left(const struct sshkey * k)3600 sshkey_signatures_left(const struct sshkey *k)
3601 {
3602 if (sshkey_type_plain(k->type) == KEY_XMSS)
3603 return sshkey_xmss_signatures_left(k);
3604 return 0;
3605 }
3606
3607 int
sshkey_enable_maxsign(struct sshkey * k,u_int32_t maxsign)3608 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
3609 {
3610 if (sshkey_type_plain(k->type) != KEY_XMSS)
3611 return SSH_ERR_INVALID_ARGUMENT;
3612 return sshkey_xmss_enable_maxsign(k, maxsign);
3613 }
3614
3615 int
sshkey_set_filename(struct sshkey * k,const char * filename)3616 sshkey_set_filename(struct sshkey *k, const char *filename)
3617 {
3618 if (k == NULL)
3619 return SSH_ERR_INVALID_ARGUMENT;
3620 if (sshkey_type_plain(k->type) != KEY_XMSS)
3621 return 0;
3622 if (filename == NULL)
3623 return SSH_ERR_INVALID_ARGUMENT;
3624 if ((k->xmss_filename = strdup(filename)) == NULL)
3625 return SSH_ERR_ALLOC_FAIL;
3626 return 0;
3627 }
3628 #else
3629 int
sshkey_private_serialize_maxsign(struct sshkey * k,struct sshbuf * b,u_int32_t maxsign,int printerror)3630 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b,
3631 u_int32_t maxsign, int printerror)
3632 {
3633 return sshkey_private_serialize_opt(k, b, SSHKEY_SERIALIZE_DEFAULT);
3634 }
3635
3636 u_int32_t
sshkey_signatures_left(const struct sshkey * k)3637 sshkey_signatures_left(const struct sshkey *k)
3638 {
3639 return 0;
3640 }
3641
3642 int
sshkey_enable_maxsign(struct sshkey * k,u_int32_t maxsign)3643 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
3644 {
3645 return SSH_ERR_INVALID_ARGUMENT;
3646 }
3647
3648 int
sshkey_set_filename(struct sshkey * k,const char * filename)3649 sshkey_set_filename(struct sshkey *k, const char *filename)
3650 {
3651 if (k == NULL)
3652 return SSH_ERR_INVALID_ARGUMENT;
3653 return 0;
3654 }
3655 #endif /* WITH_XMSS */
3656