xref: /freebsd/crypto/openssh/sshkey.c (revision 43faedc1339a9624c7acedb7f3e5624e64da5b99)
1 /* $OpenBSD: sshkey.c,v 1.21 2015/08/19 23:19:01 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 "includes.h"
29 
30 #include <sys/param.h>	/* MIN MAX */
31 #include <sys/types.h>
32 #include <netinet/in.h>
33 
34 #ifdef WITH_OPENSSL
35 #include <openssl/evp.h>
36 #include <openssl/err.h>
37 #include <openssl/pem.h>
38 #endif
39 
40 #include "crypto_api.h"
41 
42 #include <errno.h>
43 #include <limits.h>
44 #include <stdio.h>
45 #include <string.h>
46 #include <resolv.h>
47 #ifdef HAVE_UTIL_H
48 #include <util.h>
49 #endif /* HAVE_UTIL_H */
50 
51 #include "ssh2.h"
52 #include "ssherr.h"
53 #include "misc.h"
54 #include "sshbuf.h"
55 #include "rsa.h"
56 #include "cipher.h"
57 #include "digest.h"
58 #define SSHKEY_INTERNAL
59 #include "sshkey.h"
60 #include "match.h"
61 
62 /* openssh private key file format */
63 #define MARK_BEGIN		"-----BEGIN OPENSSH PRIVATE KEY-----\n"
64 #define MARK_END		"-----END OPENSSH PRIVATE KEY-----\n"
65 #define MARK_BEGIN_LEN		(sizeof(MARK_BEGIN) - 1)
66 #define MARK_END_LEN		(sizeof(MARK_END) - 1)
67 #define KDFNAME			"bcrypt"
68 #define AUTH_MAGIC		"openssh-key-v1"
69 #define SALT_LEN		16
70 #define DEFAULT_CIPHERNAME	"aes256-cbc"
71 #define	DEFAULT_ROUNDS		16
72 
73 /* Version identification string for SSH v1 identity files. */
74 #define LEGACY_BEGIN		"SSH PRIVATE KEY FILE FORMAT 1.1\n"
75 
76 static int sshkey_from_blob_internal(struct sshbuf *buf,
77     struct sshkey **keyp, int allow_cert);
78 
79 /* Supported key types */
80 struct keytype {
81 	const char *name;
82 	const char *shortname;
83 	int type;
84 	int nid;
85 	int cert;
86 };
87 static const struct keytype keytypes[] = {
88 	{ "ssh-ed25519", "ED25519", KEY_ED25519, 0, 0 },
89 	{ "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT",
90 	    KEY_ED25519_CERT, 0, 1 },
91 #ifdef WITH_OPENSSL
92 	{ NULL, "RSA1", KEY_RSA1, 0, 0 },
93 	{ "ssh-rsa", "RSA", KEY_RSA, 0, 0 },
94 	{ "ssh-dss", "DSA", KEY_DSA, 0, 0 },
95 # ifdef OPENSSL_HAS_ECC
96 	{ "ecdsa-sha2-nistp256", "ECDSA", KEY_ECDSA, NID_X9_62_prime256v1, 0 },
97 	{ "ecdsa-sha2-nistp384", "ECDSA", KEY_ECDSA, NID_secp384r1, 0 },
98 #  ifdef OPENSSL_HAS_NISTP521
99 	{ "ecdsa-sha2-nistp521", "ECDSA", KEY_ECDSA, NID_secp521r1, 0 },
100 #  endif /* OPENSSL_HAS_NISTP521 */
101 # endif /* OPENSSL_HAS_ECC */
102 	{ "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", KEY_RSA_CERT, 0, 1 },
103 	{ "ssh-dss-cert-v01@openssh.com", "DSA-CERT", KEY_DSA_CERT, 0, 1 },
104 # ifdef OPENSSL_HAS_ECC
105 	{ "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT",
106 	    KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1 },
107 	{ "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT",
108 	    KEY_ECDSA_CERT, NID_secp384r1, 1 },
109 #  ifdef OPENSSL_HAS_NISTP521
110 	{ "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT",
111 	    KEY_ECDSA_CERT, NID_secp521r1, 1 },
112 #  endif /* OPENSSL_HAS_NISTP521 */
113 # endif /* OPENSSL_HAS_ECC */
114 #endif /* WITH_OPENSSL */
115 	{ NULL, NULL, -1, -1, 0 }
116 };
117 
118 const char *
119 sshkey_type(const struct sshkey *k)
120 {
121 	const struct keytype *kt;
122 
123 	for (kt = keytypes; kt->type != -1; kt++) {
124 		if (kt->type == k->type)
125 			return kt->shortname;
126 	}
127 	return "unknown";
128 }
129 
130 static const char *
131 sshkey_ssh_name_from_type_nid(int type, int nid)
132 {
133 	const struct keytype *kt;
134 
135 	for (kt = keytypes; kt->type != -1; kt++) {
136 		if (kt->type == type && (kt->nid == 0 || kt->nid == nid))
137 			return kt->name;
138 	}
139 	return "ssh-unknown";
140 }
141 
142 int
143 sshkey_type_is_cert(int type)
144 {
145 	const struct keytype *kt;
146 
147 	for (kt = keytypes; kt->type != -1; kt++) {
148 		if (kt->type == type)
149 			return kt->cert;
150 	}
151 	return 0;
152 }
153 
154 const char *
155 sshkey_ssh_name(const struct sshkey *k)
156 {
157 	return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
158 }
159 
160 const char *
161 sshkey_ssh_name_plain(const struct sshkey *k)
162 {
163 	return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type),
164 	    k->ecdsa_nid);
165 }
166 
167 int
168 sshkey_type_from_name(const char *name)
169 {
170 	const struct keytype *kt;
171 
172 	for (kt = keytypes; kt->type != -1; kt++) {
173 		/* Only allow shortname matches for plain key types */
174 		if ((kt->name != NULL && strcmp(name, kt->name) == 0) ||
175 		    (!kt->cert && strcasecmp(kt->shortname, name) == 0))
176 			return kt->type;
177 	}
178 	return KEY_UNSPEC;
179 }
180 
181 int
182 sshkey_ecdsa_nid_from_name(const char *name)
183 {
184 	const struct keytype *kt;
185 
186 	for (kt = keytypes; kt->type != -1; kt++) {
187 		if (kt->type != KEY_ECDSA && kt->type != KEY_ECDSA_CERT)
188 			continue;
189 		if (kt->name != NULL && strcmp(name, kt->name) == 0)
190 			return kt->nid;
191 	}
192 	return -1;
193 }
194 
195 char *
196 key_alg_list(int certs_only, int plain_only)
197 {
198 	char *tmp, *ret = NULL;
199 	size_t nlen, rlen = 0;
200 	const struct keytype *kt;
201 
202 	for (kt = keytypes; kt->type != -1; kt++) {
203 		if (kt->name == NULL)
204 			continue;
205 		if ((certs_only && !kt->cert) || (plain_only && kt->cert))
206 			continue;
207 		if (ret != NULL)
208 			ret[rlen++] = '\n';
209 		nlen = strlen(kt->name);
210 		if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
211 			free(ret);
212 			return NULL;
213 		}
214 		ret = tmp;
215 		memcpy(ret + rlen, kt->name, nlen + 1);
216 		rlen += nlen;
217 	}
218 	return ret;
219 }
220 
221 int
222 sshkey_names_valid2(const char *names, int allow_wildcard)
223 {
224 	char *s, *cp, *p;
225 	const struct keytype *kt;
226 	int type;
227 
228 	if (names == NULL || strcmp(names, "") == 0)
229 		return 0;
230 	if ((s = cp = strdup(names)) == NULL)
231 		return 0;
232 	for ((p = strsep(&cp, ",")); p && *p != '\0';
233 	    (p = strsep(&cp, ","))) {
234 		type = sshkey_type_from_name(p);
235 		if (type == KEY_RSA1) {
236 			free(s);
237 			return 0;
238 		}
239 		if (type == KEY_UNSPEC) {
240 			if (allow_wildcard) {
241 				/*
242 				 * Try matching key types against the string.
243 				 * If any has a positive or negative match then
244 				 * the component is accepted.
245 				 */
246 				for (kt = keytypes; kt->type != -1; kt++) {
247 					if (kt->type == KEY_RSA1)
248 						continue;
249 					if (match_pattern_list(kt->name,
250 					    p, 0) != 0)
251 						break;
252 				}
253 				if (kt->type != -1)
254 					continue;
255 			}
256 			free(s);
257 			return 0;
258 		}
259 	}
260 	free(s);
261 	return 1;
262 }
263 
264 u_int
265 sshkey_size(const struct sshkey *k)
266 {
267 	switch (k->type) {
268 #ifdef WITH_OPENSSL
269 	case KEY_RSA1:
270 	case KEY_RSA:
271 	case KEY_RSA_CERT:
272 		return BN_num_bits(k->rsa->n);
273 	case KEY_DSA:
274 	case KEY_DSA_CERT:
275 		return BN_num_bits(k->dsa->p);
276 	case KEY_ECDSA:
277 	case KEY_ECDSA_CERT:
278 		return sshkey_curve_nid_to_bits(k->ecdsa_nid);
279 #endif /* WITH_OPENSSL */
280 	case KEY_ED25519:
281 	case KEY_ED25519_CERT:
282 		return 256;	/* XXX */
283 	}
284 	return 0;
285 }
286 
287 static int
288 sshkey_type_is_valid_ca(int type)
289 {
290 	switch (type) {
291 	case KEY_RSA:
292 	case KEY_DSA:
293 	case KEY_ECDSA:
294 	case KEY_ED25519:
295 		return 1;
296 	default:
297 		return 0;
298 	}
299 }
300 
301 int
302 sshkey_is_cert(const struct sshkey *k)
303 {
304 	if (k == NULL)
305 		return 0;
306 	return sshkey_type_is_cert(k->type);
307 }
308 
309 /* Return the cert-less equivalent to a certified key type */
310 int
311 sshkey_type_plain(int type)
312 {
313 	switch (type) {
314 	case KEY_RSA_CERT:
315 		return KEY_RSA;
316 	case KEY_DSA_CERT:
317 		return KEY_DSA;
318 	case KEY_ECDSA_CERT:
319 		return KEY_ECDSA;
320 	case KEY_ED25519_CERT:
321 		return KEY_ED25519;
322 	default:
323 		return type;
324 	}
325 }
326 
327 #ifdef WITH_OPENSSL
328 /* XXX: these are really begging for a table-driven approach */
329 int
330 sshkey_curve_name_to_nid(const char *name)
331 {
332 	if (strcmp(name, "nistp256") == 0)
333 		return NID_X9_62_prime256v1;
334 	else if (strcmp(name, "nistp384") == 0)
335 		return NID_secp384r1;
336 # ifdef OPENSSL_HAS_NISTP521
337 	else if (strcmp(name, "nistp521") == 0)
338 		return NID_secp521r1;
339 # endif /* OPENSSL_HAS_NISTP521 */
340 	else
341 		return -1;
342 }
343 
344 u_int
345 sshkey_curve_nid_to_bits(int nid)
346 {
347 	switch (nid) {
348 	case NID_X9_62_prime256v1:
349 		return 256;
350 	case NID_secp384r1:
351 		return 384;
352 # ifdef OPENSSL_HAS_NISTP521
353 	case NID_secp521r1:
354 		return 521;
355 # endif /* OPENSSL_HAS_NISTP521 */
356 	default:
357 		return 0;
358 	}
359 }
360 
361 int
362 sshkey_ecdsa_bits_to_nid(int bits)
363 {
364 	switch (bits) {
365 	case 256:
366 		return NID_X9_62_prime256v1;
367 	case 384:
368 		return NID_secp384r1;
369 # ifdef OPENSSL_HAS_NISTP521
370 	case 521:
371 		return NID_secp521r1;
372 # endif /* OPENSSL_HAS_NISTP521 */
373 	default:
374 		return -1;
375 	}
376 }
377 
378 const char *
379 sshkey_curve_nid_to_name(int nid)
380 {
381 	switch (nid) {
382 	case NID_X9_62_prime256v1:
383 		return "nistp256";
384 	case NID_secp384r1:
385 		return "nistp384";
386 # ifdef OPENSSL_HAS_NISTP521
387 	case NID_secp521r1:
388 		return "nistp521";
389 # endif /* OPENSSL_HAS_NISTP521 */
390 	default:
391 		return NULL;
392 	}
393 }
394 
395 int
396 sshkey_ec_nid_to_hash_alg(int nid)
397 {
398 	int kbits = sshkey_curve_nid_to_bits(nid);
399 
400 	if (kbits <= 0)
401 		return -1;
402 
403 	/* RFC5656 section 6.2.1 */
404 	if (kbits <= 256)
405 		return SSH_DIGEST_SHA256;
406 	else if (kbits <= 384)
407 		return SSH_DIGEST_SHA384;
408 	else
409 		return SSH_DIGEST_SHA512;
410 }
411 #endif /* WITH_OPENSSL */
412 
413 static void
414 cert_free(struct sshkey_cert *cert)
415 {
416 	u_int i;
417 
418 	if (cert == NULL)
419 		return;
420 	if (cert->certblob != NULL)
421 		sshbuf_free(cert->certblob);
422 	if (cert->critical != NULL)
423 		sshbuf_free(cert->critical);
424 	if (cert->extensions != NULL)
425 		sshbuf_free(cert->extensions);
426 	if (cert->key_id != NULL)
427 		free(cert->key_id);
428 	for (i = 0; i < cert->nprincipals; i++)
429 		free(cert->principals[i]);
430 	if (cert->principals != NULL)
431 		free(cert->principals);
432 	if (cert->signature_key != NULL)
433 		sshkey_free(cert->signature_key);
434 	explicit_bzero(cert, sizeof(*cert));
435 	free(cert);
436 }
437 
438 static struct sshkey_cert *
439 cert_new(void)
440 {
441 	struct sshkey_cert *cert;
442 
443 	if ((cert = calloc(1, sizeof(*cert))) == NULL)
444 		return NULL;
445 	if ((cert->certblob = sshbuf_new()) == NULL ||
446 	    (cert->critical = sshbuf_new()) == NULL ||
447 	    (cert->extensions = sshbuf_new()) == NULL) {
448 		cert_free(cert);
449 		return NULL;
450 	}
451 	cert->key_id = NULL;
452 	cert->principals = NULL;
453 	cert->signature_key = NULL;
454 	return cert;
455 }
456 
457 struct sshkey *
458 sshkey_new(int type)
459 {
460 	struct sshkey *k;
461 #ifdef WITH_OPENSSL
462 	RSA *rsa;
463 	DSA *dsa;
464 #endif /* WITH_OPENSSL */
465 
466 	if ((k = calloc(1, sizeof(*k))) == NULL)
467 		return NULL;
468 	k->type = type;
469 	k->ecdsa = NULL;
470 	k->ecdsa_nid = -1;
471 	k->dsa = NULL;
472 	k->rsa = NULL;
473 	k->cert = NULL;
474 	k->ed25519_sk = NULL;
475 	k->ed25519_pk = NULL;
476 	switch (k->type) {
477 #ifdef WITH_OPENSSL
478 	case KEY_RSA1:
479 	case KEY_RSA:
480 	case KEY_RSA_CERT:
481 		if ((rsa = RSA_new()) == NULL ||
482 		    (rsa->n = BN_new()) == NULL ||
483 		    (rsa->e = BN_new()) == NULL) {
484 			if (rsa != NULL)
485 				RSA_free(rsa);
486 			free(k);
487 			return NULL;
488 		}
489 		k->rsa = rsa;
490 		break;
491 	case KEY_DSA:
492 	case KEY_DSA_CERT:
493 		if ((dsa = DSA_new()) == NULL ||
494 		    (dsa->p = BN_new()) == NULL ||
495 		    (dsa->q = BN_new()) == NULL ||
496 		    (dsa->g = BN_new()) == NULL ||
497 		    (dsa->pub_key = BN_new()) == NULL) {
498 			if (dsa != NULL)
499 				DSA_free(dsa);
500 			free(k);
501 			return NULL;
502 		}
503 		k->dsa = dsa;
504 		break;
505 	case KEY_ECDSA:
506 	case KEY_ECDSA_CERT:
507 		/* Cannot do anything until we know the group */
508 		break;
509 #endif /* WITH_OPENSSL */
510 	case KEY_ED25519:
511 	case KEY_ED25519_CERT:
512 		/* no need to prealloc */
513 		break;
514 	case KEY_UNSPEC:
515 		break;
516 	default:
517 		free(k);
518 		return NULL;
519 		break;
520 	}
521 
522 	if (sshkey_is_cert(k)) {
523 		if ((k->cert = cert_new()) == NULL) {
524 			sshkey_free(k);
525 			return NULL;
526 		}
527 	}
528 
529 	return k;
530 }
531 
532 int
533 sshkey_add_private(struct sshkey *k)
534 {
535 	switch (k->type) {
536 #ifdef WITH_OPENSSL
537 	case KEY_RSA1:
538 	case KEY_RSA:
539 	case KEY_RSA_CERT:
540 #define bn_maybe_alloc_failed(p) (p == NULL && (p = BN_new()) == NULL)
541 		if (bn_maybe_alloc_failed(k->rsa->d) ||
542 		    bn_maybe_alloc_failed(k->rsa->iqmp) ||
543 		    bn_maybe_alloc_failed(k->rsa->q) ||
544 		    bn_maybe_alloc_failed(k->rsa->p) ||
545 		    bn_maybe_alloc_failed(k->rsa->dmq1) ||
546 		    bn_maybe_alloc_failed(k->rsa->dmp1))
547 			return SSH_ERR_ALLOC_FAIL;
548 		break;
549 	case KEY_DSA:
550 	case KEY_DSA_CERT:
551 		if (bn_maybe_alloc_failed(k->dsa->priv_key))
552 			return SSH_ERR_ALLOC_FAIL;
553 		break;
554 #undef bn_maybe_alloc_failed
555 	case KEY_ECDSA:
556 	case KEY_ECDSA_CERT:
557 		/* Cannot do anything until we know the group */
558 		break;
559 #endif /* WITH_OPENSSL */
560 	case KEY_ED25519:
561 	case KEY_ED25519_CERT:
562 		/* no need to prealloc */
563 		break;
564 	case KEY_UNSPEC:
565 		break;
566 	default:
567 		return SSH_ERR_INVALID_ARGUMENT;
568 	}
569 	return 0;
570 }
571 
572 struct sshkey *
573 sshkey_new_private(int type)
574 {
575 	struct sshkey *k = sshkey_new(type);
576 
577 	if (k == NULL)
578 		return NULL;
579 	if (sshkey_add_private(k) != 0) {
580 		sshkey_free(k);
581 		return NULL;
582 	}
583 	return k;
584 }
585 
586 void
587 sshkey_free(struct sshkey *k)
588 {
589 	if (k == NULL)
590 		return;
591 	switch (k->type) {
592 #ifdef WITH_OPENSSL
593 	case KEY_RSA1:
594 	case KEY_RSA:
595 	case KEY_RSA_CERT:
596 		if (k->rsa != NULL)
597 			RSA_free(k->rsa);
598 		k->rsa = NULL;
599 		break;
600 	case KEY_DSA:
601 	case KEY_DSA_CERT:
602 		if (k->dsa != NULL)
603 			DSA_free(k->dsa);
604 		k->dsa = NULL;
605 		break;
606 # ifdef OPENSSL_HAS_ECC
607 	case KEY_ECDSA:
608 	case KEY_ECDSA_CERT:
609 		if (k->ecdsa != NULL)
610 			EC_KEY_free(k->ecdsa);
611 		k->ecdsa = NULL;
612 		break;
613 # endif /* OPENSSL_HAS_ECC */
614 #endif /* WITH_OPENSSL */
615 	case KEY_ED25519:
616 	case KEY_ED25519_CERT:
617 		if (k->ed25519_pk) {
618 			explicit_bzero(k->ed25519_pk, ED25519_PK_SZ);
619 			free(k->ed25519_pk);
620 			k->ed25519_pk = NULL;
621 		}
622 		if (k->ed25519_sk) {
623 			explicit_bzero(k->ed25519_sk, ED25519_SK_SZ);
624 			free(k->ed25519_sk);
625 			k->ed25519_sk = NULL;
626 		}
627 		break;
628 	case KEY_UNSPEC:
629 		break;
630 	default:
631 		break;
632 	}
633 	if (sshkey_is_cert(k))
634 		cert_free(k->cert);
635 	explicit_bzero(k, sizeof(*k));
636 	free(k);
637 }
638 
639 static int
640 cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
641 {
642 	if (a == NULL && b == NULL)
643 		return 1;
644 	if (a == NULL || b == NULL)
645 		return 0;
646 	if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob))
647 		return 0;
648 	if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob),
649 	    sshbuf_len(a->certblob)) != 0)
650 		return 0;
651 	return 1;
652 }
653 
654 /*
655  * Compare public portions of key only, allowing comparisons between
656  * certificates and plain keys too.
657  */
658 int
659 sshkey_equal_public(const struct sshkey *a, const struct sshkey *b)
660 {
661 #if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
662 	BN_CTX *bnctx;
663 #endif /* WITH_OPENSSL && OPENSSL_HAS_ECC */
664 
665 	if (a == NULL || b == NULL ||
666 	    sshkey_type_plain(a->type) != sshkey_type_plain(b->type))
667 		return 0;
668 
669 	switch (a->type) {
670 #ifdef WITH_OPENSSL
671 	case KEY_RSA1:
672 	case KEY_RSA_CERT:
673 	case KEY_RSA:
674 		return a->rsa != NULL && b->rsa != NULL &&
675 		    BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
676 		    BN_cmp(a->rsa->n, b->rsa->n) == 0;
677 	case KEY_DSA_CERT:
678 	case KEY_DSA:
679 		return a->dsa != NULL && b->dsa != NULL &&
680 		    BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
681 		    BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
682 		    BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
683 		    BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
684 # ifdef OPENSSL_HAS_ECC
685 	case KEY_ECDSA_CERT:
686 	case KEY_ECDSA:
687 		if (a->ecdsa == NULL || b->ecdsa == NULL ||
688 		    EC_KEY_get0_public_key(a->ecdsa) == NULL ||
689 		    EC_KEY_get0_public_key(b->ecdsa) == NULL)
690 			return 0;
691 		if ((bnctx = BN_CTX_new()) == NULL)
692 			return 0;
693 		if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
694 		    EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
695 		    EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
696 		    EC_KEY_get0_public_key(a->ecdsa),
697 		    EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
698 			BN_CTX_free(bnctx);
699 			return 0;
700 		}
701 		BN_CTX_free(bnctx);
702 		return 1;
703 # endif /* OPENSSL_HAS_ECC */
704 #endif /* WITH_OPENSSL */
705 	case KEY_ED25519:
706 	case KEY_ED25519_CERT:
707 		return a->ed25519_pk != NULL && b->ed25519_pk != NULL &&
708 		    memcmp(a->ed25519_pk, b->ed25519_pk, ED25519_PK_SZ) == 0;
709 	default:
710 		return 0;
711 	}
712 	/* NOTREACHED */
713 }
714 
715 int
716 sshkey_equal(const struct sshkey *a, const struct sshkey *b)
717 {
718 	if (a == NULL || b == NULL || a->type != b->type)
719 		return 0;
720 	if (sshkey_is_cert(a)) {
721 		if (!cert_compare(a->cert, b->cert))
722 			return 0;
723 	}
724 	return sshkey_equal_public(a, b);
725 }
726 
727 static int
728 to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain)
729 {
730 	int type, ret = SSH_ERR_INTERNAL_ERROR;
731 	const char *typename;
732 
733 	if (key == NULL)
734 		return SSH_ERR_INVALID_ARGUMENT;
735 
736 	if (sshkey_is_cert(key)) {
737 		if (key->cert == NULL)
738 			return SSH_ERR_EXPECTED_CERT;
739 		if (sshbuf_len(key->cert->certblob) == 0)
740 			return SSH_ERR_KEY_LACKS_CERTBLOB;
741 	}
742 	type = force_plain ? sshkey_type_plain(key->type) : key->type;
743 	typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid);
744 
745 	switch (type) {
746 #ifdef WITH_OPENSSL
747 	case KEY_DSA_CERT:
748 	case KEY_ECDSA_CERT:
749 	case KEY_RSA_CERT:
750 #endif /* WITH_OPENSSL */
751 	case KEY_ED25519_CERT:
752 		/* Use the existing blob */
753 		/* XXX modified flag? */
754 		if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0)
755 			return ret;
756 		break;
757 #ifdef WITH_OPENSSL
758 	case KEY_DSA:
759 		if (key->dsa == NULL)
760 			return SSH_ERR_INVALID_ARGUMENT;
761 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
762 		    (ret = sshbuf_put_bignum2(b, key->dsa->p)) != 0 ||
763 		    (ret = sshbuf_put_bignum2(b, key->dsa->q)) != 0 ||
764 		    (ret = sshbuf_put_bignum2(b, key->dsa->g)) != 0 ||
765 		    (ret = sshbuf_put_bignum2(b, key->dsa->pub_key)) != 0)
766 			return ret;
767 		break;
768 # ifdef OPENSSL_HAS_ECC
769 	case KEY_ECDSA:
770 		if (key->ecdsa == NULL)
771 			return SSH_ERR_INVALID_ARGUMENT;
772 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
773 		    (ret = sshbuf_put_cstring(b,
774 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
775 		    (ret = sshbuf_put_eckey(b, key->ecdsa)) != 0)
776 			return ret;
777 		break;
778 # endif
779 	case KEY_RSA:
780 		if (key->rsa == NULL)
781 			return SSH_ERR_INVALID_ARGUMENT;
782 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
783 		    (ret = sshbuf_put_bignum2(b, key->rsa->e)) != 0 ||
784 		    (ret = sshbuf_put_bignum2(b, key->rsa->n)) != 0)
785 			return ret;
786 		break;
787 #endif /* WITH_OPENSSL */
788 	case KEY_ED25519:
789 		if (key->ed25519_pk == NULL)
790 			return SSH_ERR_INVALID_ARGUMENT;
791 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
792 		    (ret = sshbuf_put_string(b,
793 		    key->ed25519_pk, ED25519_PK_SZ)) != 0)
794 			return ret;
795 		break;
796 	default:
797 		return SSH_ERR_KEY_TYPE_UNKNOWN;
798 	}
799 	return 0;
800 }
801 
802 int
803 sshkey_putb(const struct sshkey *key, struct sshbuf *b)
804 {
805 	return to_blob_buf(key, b, 0);
806 }
807 
808 int
809 sshkey_puts(const struct sshkey *key, struct sshbuf *b)
810 {
811 	struct sshbuf *tmp;
812 	int r;
813 
814 	if ((tmp = sshbuf_new()) == NULL)
815 		return SSH_ERR_ALLOC_FAIL;
816 	r = to_blob_buf(key, tmp, 0);
817 	if (r == 0)
818 		r = sshbuf_put_stringb(b, tmp);
819 	sshbuf_free(tmp);
820 	return r;
821 }
822 
823 int
824 sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b)
825 {
826 	return to_blob_buf(key, b, 1);
827 }
828 
829 static int
830 to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain)
831 {
832 	int ret = SSH_ERR_INTERNAL_ERROR;
833 	size_t len;
834 	struct sshbuf *b = NULL;
835 
836 	if (lenp != NULL)
837 		*lenp = 0;
838 	if (blobp != NULL)
839 		*blobp = NULL;
840 	if ((b = sshbuf_new()) == NULL)
841 		return SSH_ERR_ALLOC_FAIL;
842 	if ((ret = to_blob_buf(key, b, force_plain)) != 0)
843 		goto out;
844 	len = sshbuf_len(b);
845 	if (lenp != NULL)
846 		*lenp = len;
847 	if (blobp != NULL) {
848 		if ((*blobp = malloc(len)) == NULL) {
849 			ret = SSH_ERR_ALLOC_FAIL;
850 			goto out;
851 		}
852 		memcpy(*blobp, sshbuf_ptr(b), len);
853 	}
854 	ret = 0;
855  out:
856 	sshbuf_free(b);
857 	return ret;
858 }
859 
860 int
861 sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
862 {
863 	return to_blob(key, blobp, lenp, 0);
864 }
865 
866 int
867 sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
868 {
869 	return to_blob(key, blobp, lenp, 1);
870 }
871 
872 int
873 sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg,
874     u_char **retp, size_t *lenp)
875 {
876 	u_char *blob = NULL, *ret = NULL;
877 	size_t blob_len = 0;
878 	int r = SSH_ERR_INTERNAL_ERROR;
879 
880 	if (retp != NULL)
881 		*retp = NULL;
882 	if (lenp != NULL)
883 		*lenp = 0;
884 	if (ssh_digest_bytes(dgst_alg) == 0) {
885 		r = SSH_ERR_INVALID_ARGUMENT;
886 		goto out;
887 	}
888 
889 	if (k->type == KEY_RSA1) {
890 #ifdef WITH_OPENSSL
891 		int nlen = BN_num_bytes(k->rsa->n);
892 		int elen = BN_num_bytes(k->rsa->e);
893 
894 		blob_len = nlen + elen;
895 		if (nlen >= INT_MAX - elen ||
896 		    (blob = malloc(blob_len)) == NULL) {
897 			r = SSH_ERR_ALLOC_FAIL;
898 			goto out;
899 		}
900 		BN_bn2bin(k->rsa->n, blob);
901 		BN_bn2bin(k->rsa->e, blob + nlen);
902 #endif /* WITH_OPENSSL */
903 	} else if ((r = to_blob(k, &blob, &blob_len, 1)) != 0)
904 		goto out;
905 	if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) {
906 		r = SSH_ERR_ALLOC_FAIL;
907 		goto out;
908 	}
909 	if ((r = ssh_digest_memory(dgst_alg, blob, blob_len,
910 	    ret, SSH_DIGEST_MAX_LENGTH)) != 0)
911 		goto out;
912 	/* success */
913 	if (retp != NULL) {
914 		*retp = ret;
915 		ret = NULL;
916 	}
917 	if (lenp != NULL)
918 		*lenp = ssh_digest_bytes(dgst_alg);
919 	r = 0;
920  out:
921 	free(ret);
922 	if (blob != NULL) {
923 		explicit_bzero(blob, blob_len);
924 		free(blob);
925 	}
926 	return r;
927 }
928 
929 static char *
930 fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
931 {
932 	char *ret;
933 	size_t plen = strlen(alg) + 1;
934 	size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1;
935 	int r;
936 
937 	if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL)
938 		return NULL;
939 	strlcpy(ret, alg, rlen);
940 	strlcat(ret, ":", rlen);
941 	if (dgst_raw_len == 0)
942 		return ret;
943 	if ((r = b64_ntop(dgst_raw, dgst_raw_len,
944 	    ret + plen, rlen - plen)) == -1) {
945 		explicit_bzero(ret, rlen);
946 		free(ret);
947 		return NULL;
948 	}
949 	/* Trim padding characters from end */
950 	ret[strcspn(ret, "=")] = '\0';
951 	return ret;
952 }
953 
954 static char *
955 fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
956 {
957 	char *retval, hex[5];
958 	size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2;
959 
960 	if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL)
961 		return NULL;
962 	strlcpy(retval, alg, rlen);
963 	strlcat(retval, ":", rlen);
964 	for (i = 0; i < dgst_raw_len; i++) {
965 		snprintf(hex, sizeof(hex), "%s%02x",
966 		    i > 0 ? ":" : "", dgst_raw[i]);
967 		strlcat(retval, hex, rlen);
968 	}
969 	return retval;
970 }
971 
972 static char *
973 fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len)
974 {
975 	char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
976 	char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
977 	    'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
978 	u_int i, j = 0, rounds, seed = 1;
979 	char *retval;
980 
981 	rounds = (dgst_raw_len / 2) + 1;
982 	if ((retval = calloc(rounds, 6)) == NULL)
983 		return NULL;
984 	retval[j++] = 'x';
985 	for (i = 0; i < rounds; i++) {
986 		u_int idx0, idx1, idx2, idx3, idx4;
987 		if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
988 			idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
989 			    seed) % 6;
990 			idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
991 			idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
992 			    (seed / 6)) % 6;
993 			retval[j++] = vowels[idx0];
994 			retval[j++] = consonants[idx1];
995 			retval[j++] = vowels[idx2];
996 			if ((i + 1) < rounds) {
997 				idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
998 				idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
999 				retval[j++] = consonants[idx3];
1000 				retval[j++] = '-';
1001 				retval[j++] = consonants[idx4];
1002 				seed = ((seed * 5) +
1003 				    ((((u_int)(dgst_raw[2 * i])) * 7) +
1004 				    ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
1005 			}
1006 		} else {
1007 			idx0 = seed % 6;
1008 			idx1 = 16;
1009 			idx2 = seed / 6;
1010 			retval[j++] = vowels[idx0];
1011 			retval[j++] = consonants[idx1];
1012 			retval[j++] = vowels[idx2];
1013 		}
1014 	}
1015 	retval[j++] = 'x';
1016 	retval[j++] = '\0';
1017 	return retval;
1018 }
1019 
1020 /*
1021  * Draw an ASCII-Art representing the fingerprint so human brain can
1022  * profit from its built-in pattern recognition ability.
1023  * This technique is called "random art" and can be found in some
1024  * scientific publications like this original paper:
1025  *
1026  * "Hash Visualization: a New Technique to improve Real-World Security",
1027  * Perrig A. and Song D., 1999, International Workshop on Cryptographic
1028  * Techniques and E-Commerce (CrypTEC '99)
1029  * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
1030  *
1031  * The subject came up in a talk by Dan Kaminsky, too.
1032  *
1033  * If you see the picture is different, the key is different.
1034  * If the picture looks the same, you still know nothing.
1035  *
1036  * The algorithm used here is a worm crawling over a discrete plane,
1037  * leaving a trace (augmenting the field) everywhere it goes.
1038  * Movement is taken from dgst_raw 2bit-wise.  Bumping into walls
1039  * makes the respective movement vector be ignored for this turn.
1040  * Graphs are not unambiguous, because circles in graphs can be
1041  * walked in either direction.
1042  */
1043 
1044 /*
1045  * Field sizes for the random art.  Have to be odd, so the starting point
1046  * can be in the exact middle of the picture, and FLDBASE should be >=8 .
1047  * Else pictures would be too dense, and drawing the frame would
1048  * fail, too, because the key type would not fit in anymore.
1049  */
1050 #define	FLDBASE		8
1051 #define	FLDSIZE_Y	(FLDBASE + 1)
1052 #define	FLDSIZE_X	(FLDBASE * 2 + 1)
1053 static char *
1054 fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
1055     const struct sshkey *k)
1056 {
1057 	/*
1058 	 * Chars to be used after each other every time the worm
1059 	 * intersects with itself.  Matter of taste.
1060 	 */
1061 	char	*augmentation_string = " .o+=*BOX@%&#/^SE";
1062 	char	*retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
1063 	u_char	 field[FLDSIZE_X][FLDSIZE_Y];
1064 	size_t	 i, tlen, hlen;
1065 	u_int	 b;
1066 	int	 x, y, r;
1067 	size_t	 len = strlen(augmentation_string) - 1;
1068 
1069 	if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
1070 		return NULL;
1071 
1072 	/* initialize field */
1073 	memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1074 	x = FLDSIZE_X / 2;
1075 	y = FLDSIZE_Y / 2;
1076 
1077 	/* process raw key */
1078 	for (i = 0; i < dgst_raw_len; i++) {
1079 		int input;
1080 		/* each byte conveys four 2-bit move commands */
1081 		input = dgst_raw[i];
1082 		for (b = 0; b < 4; b++) {
1083 			/* evaluate 2 bit, rest is shifted later */
1084 			x += (input & 0x1) ? 1 : -1;
1085 			y += (input & 0x2) ? 1 : -1;
1086 
1087 			/* assure we are still in bounds */
1088 			x = MAX(x, 0);
1089 			y = MAX(y, 0);
1090 			x = MIN(x, FLDSIZE_X - 1);
1091 			y = MIN(y, FLDSIZE_Y - 1);
1092 
1093 			/* augment the field */
1094 			if (field[x][y] < len - 2)
1095 				field[x][y]++;
1096 			input = input >> 2;
1097 		}
1098 	}
1099 
1100 	/* mark starting point and end point*/
1101 	field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
1102 	field[x][y] = len;
1103 
1104 	/* assemble title */
1105 	r = snprintf(title, sizeof(title), "[%s %u]",
1106 		sshkey_type(k), sshkey_size(k));
1107 	/* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */
1108 	if (r < 0 || r > (int)sizeof(title))
1109 		r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k));
1110 	tlen = (r <= 0) ? 0 : strlen(title);
1111 
1112 	/* assemble hash ID. */
1113 	r = snprintf(hash, sizeof(hash), "[%s]", alg);
1114 	hlen = (r <= 0) ? 0 : strlen(hash);
1115 
1116 	/* output upper border */
1117 	p = retval;
1118 	*p++ = '+';
1119 	for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
1120 		*p++ = '-';
1121 	memcpy(p, title, tlen);
1122 	p += tlen;
1123 	for (i += tlen; i < FLDSIZE_X; i++)
1124 		*p++ = '-';
1125 	*p++ = '+';
1126 	*p++ = '\n';
1127 
1128 	/* output content */
1129 	for (y = 0; y < FLDSIZE_Y; y++) {
1130 		*p++ = '|';
1131 		for (x = 0; x < FLDSIZE_X; x++)
1132 			*p++ = augmentation_string[MIN(field[x][y], len)];
1133 		*p++ = '|';
1134 		*p++ = '\n';
1135 	}
1136 
1137 	/* output lower border */
1138 	*p++ = '+';
1139 	for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
1140 		*p++ = '-';
1141 	memcpy(p, hash, hlen);
1142 	p += hlen;
1143 	for (i += hlen; i < FLDSIZE_X; i++)
1144 		*p++ = '-';
1145 	*p++ = '+';
1146 
1147 	return retval;
1148 }
1149 
1150 char *
1151 sshkey_fingerprint(const struct sshkey *k, int dgst_alg,
1152     enum sshkey_fp_rep dgst_rep)
1153 {
1154 	char *retval = NULL;
1155 	u_char *dgst_raw;
1156 	size_t dgst_raw_len;
1157 
1158 	if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0)
1159 		return NULL;
1160 	switch (dgst_rep) {
1161 	case SSH_FP_DEFAULT:
1162 		if (dgst_alg == SSH_DIGEST_MD5) {
1163 			retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1164 			    dgst_raw, dgst_raw_len);
1165 		} else {
1166 			retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1167 			    dgst_raw, dgst_raw_len);
1168 		}
1169 		break;
1170 	case SSH_FP_HEX:
1171 		retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1172 		    dgst_raw, dgst_raw_len);
1173 		break;
1174 	case SSH_FP_BASE64:
1175 		retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1176 		    dgst_raw, dgst_raw_len);
1177 		break;
1178 	case SSH_FP_BUBBLEBABBLE:
1179 		retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1180 		break;
1181 	case SSH_FP_RANDOMART:
1182 		retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg),
1183 		    dgst_raw, dgst_raw_len, k);
1184 		break;
1185 	default:
1186 		explicit_bzero(dgst_raw, dgst_raw_len);
1187 		free(dgst_raw);
1188 		return NULL;
1189 	}
1190 	explicit_bzero(dgst_raw, dgst_raw_len);
1191 	free(dgst_raw);
1192 	return retval;
1193 }
1194 
1195 #ifdef WITH_SSH1
1196 /*
1197  * Reads a multiple-precision integer in decimal from the buffer, and advances
1198  * the pointer.  The integer must already be initialized.  This function is
1199  * permitted to modify the buffer.  This leaves *cpp to point just beyond the
1200  * last processed character.
1201  */
1202 static int
1203 read_decimal_bignum(char **cpp, BIGNUM *v)
1204 {
1205 	char *cp;
1206 	size_t e;
1207 	int skip = 1;	/* skip white space */
1208 
1209 	cp = *cpp;
1210 	while (*cp == ' ' || *cp == '\t')
1211 		cp++;
1212 	e = strspn(cp, "0123456789");
1213 	if (e == 0)
1214 		return SSH_ERR_INVALID_FORMAT;
1215 	if (e > SSHBUF_MAX_BIGNUM * 3)
1216 		return SSH_ERR_BIGNUM_TOO_LARGE;
1217 	if (cp[e] == '\0')
1218 		skip = 0;
1219 	else if (index(" \t\r\n", cp[e]) == NULL)
1220 		return SSH_ERR_INVALID_FORMAT;
1221 	cp[e] = '\0';
1222 	if (BN_dec2bn(&v, cp) <= 0)
1223 		return SSH_ERR_INVALID_FORMAT;
1224 	*cpp = cp + e + skip;
1225 	return 0;
1226 }
1227 #endif /* WITH_SSH1 */
1228 
1229 /* returns 0 ok, and < 0 error */
1230 int
1231 sshkey_read(struct sshkey *ret, char **cpp)
1232 {
1233 	struct sshkey *k;
1234 	int retval = SSH_ERR_INVALID_FORMAT;
1235 	char *cp, *space;
1236 	int r, type, curve_nid = -1;
1237 	struct sshbuf *blob;
1238 #ifdef WITH_SSH1
1239 	char *ep;
1240 	u_long bits;
1241 #endif /* WITH_SSH1 */
1242 
1243 	cp = *cpp;
1244 
1245 	switch (ret->type) {
1246 	case KEY_RSA1:
1247 #ifdef WITH_SSH1
1248 		/* Get number of bits. */
1249 		bits = strtoul(cp, &ep, 10);
1250 		if (*cp == '\0' || index(" \t\r\n", *ep) == NULL ||
1251 		    bits == 0 || bits > SSHBUF_MAX_BIGNUM * 8)
1252 			return SSH_ERR_INVALID_FORMAT;	/* Bad bit count... */
1253 		/* Get public exponent, public modulus. */
1254 		if ((r = read_decimal_bignum(&ep, ret->rsa->e)) < 0)
1255 			return r;
1256 		if ((r = read_decimal_bignum(&ep, ret->rsa->n)) < 0)
1257 			return r;
1258 		*cpp = ep;
1259 		/* validate the claimed number of bits */
1260 		if (BN_num_bits(ret->rsa->n) != (int)bits)
1261 			return SSH_ERR_KEY_BITS_MISMATCH;
1262 		retval = 0;
1263 #endif /* WITH_SSH1 */
1264 		break;
1265 	case KEY_UNSPEC:
1266 	case KEY_RSA:
1267 	case KEY_DSA:
1268 	case KEY_ECDSA:
1269 	case KEY_ED25519:
1270 	case KEY_DSA_CERT:
1271 	case KEY_ECDSA_CERT:
1272 	case KEY_RSA_CERT:
1273 	case KEY_ED25519_CERT:
1274 		space = strchr(cp, ' ');
1275 		if (space == NULL)
1276 			return SSH_ERR_INVALID_FORMAT;
1277 		*space = '\0';
1278 		type = sshkey_type_from_name(cp);
1279 		if (sshkey_type_plain(type) == KEY_ECDSA &&
1280 		    (curve_nid = sshkey_ecdsa_nid_from_name(cp)) == -1)
1281 			return SSH_ERR_EC_CURVE_INVALID;
1282 		*space = ' ';
1283 		if (type == KEY_UNSPEC)
1284 			return SSH_ERR_INVALID_FORMAT;
1285 		cp = space+1;
1286 		if (*cp == '\0')
1287 			return SSH_ERR_INVALID_FORMAT;
1288 		if (ret->type != KEY_UNSPEC && ret->type != type)
1289 			return SSH_ERR_KEY_TYPE_MISMATCH;
1290 		if ((blob = sshbuf_new()) == NULL)
1291 			return SSH_ERR_ALLOC_FAIL;
1292 		/* trim comment */
1293 		space = strchr(cp, ' ');
1294 		if (space) {
1295 			/* advance 'space': skip whitespace */
1296 			*space++ = '\0';
1297 			while (*space == ' ' || *space == '\t')
1298 				space++;
1299 			*cpp = space;
1300 		} else
1301 			*cpp = cp + strlen(cp);
1302 		if ((r = sshbuf_b64tod(blob, cp)) != 0) {
1303 			sshbuf_free(blob);
1304 			return r;
1305 		}
1306 		if ((r = sshkey_from_blob(sshbuf_ptr(blob),
1307 		    sshbuf_len(blob), &k)) != 0) {
1308 			sshbuf_free(blob);
1309 			return r;
1310 		}
1311 		sshbuf_free(blob);
1312 		if (k->type != type) {
1313 			sshkey_free(k);
1314 			return SSH_ERR_KEY_TYPE_MISMATCH;
1315 		}
1316 		if (sshkey_type_plain(type) == KEY_ECDSA &&
1317 		    curve_nid != k->ecdsa_nid) {
1318 			sshkey_free(k);
1319 			return SSH_ERR_EC_CURVE_MISMATCH;
1320 		}
1321 		ret->type = type;
1322 		if (sshkey_is_cert(ret)) {
1323 			if (!sshkey_is_cert(k)) {
1324 				sshkey_free(k);
1325 				return SSH_ERR_EXPECTED_CERT;
1326 			}
1327 			if (ret->cert != NULL)
1328 				cert_free(ret->cert);
1329 			ret->cert = k->cert;
1330 			k->cert = NULL;
1331 		}
1332 #ifdef WITH_OPENSSL
1333 		if (sshkey_type_plain(ret->type) == KEY_RSA) {
1334 			if (ret->rsa != NULL)
1335 				RSA_free(ret->rsa);
1336 			ret->rsa = k->rsa;
1337 			k->rsa = NULL;
1338 #ifdef DEBUG_PK
1339 			RSA_print_fp(stderr, ret->rsa, 8);
1340 #endif
1341 		}
1342 		if (sshkey_type_plain(ret->type) == KEY_DSA) {
1343 			if (ret->dsa != NULL)
1344 				DSA_free(ret->dsa);
1345 			ret->dsa = k->dsa;
1346 			k->dsa = NULL;
1347 #ifdef DEBUG_PK
1348 			DSA_print_fp(stderr, ret->dsa, 8);
1349 #endif
1350 		}
1351 # ifdef OPENSSL_HAS_ECC
1352 		if (sshkey_type_plain(ret->type) == KEY_ECDSA) {
1353 			if (ret->ecdsa != NULL)
1354 				EC_KEY_free(ret->ecdsa);
1355 			ret->ecdsa = k->ecdsa;
1356 			ret->ecdsa_nid = k->ecdsa_nid;
1357 			k->ecdsa = NULL;
1358 			k->ecdsa_nid = -1;
1359 #ifdef DEBUG_PK
1360 			sshkey_dump_ec_key(ret->ecdsa);
1361 #endif
1362 		}
1363 # endif /* OPENSSL_HAS_ECC */
1364 #endif /* WITH_OPENSSL */
1365 		if (sshkey_type_plain(ret->type) == KEY_ED25519) {
1366 			free(ret->ed25519_pk);
1367 			ret->ed25519_pk = k->ed25519_pk;
1368 			k->ed25519_pk = NULL;
1369 #ifdef DEBUG_PK
1370 			/* XXX */
1371 #endif
1372 		}
1373 		retval = 0;
1374 /*XXXX*/
1375 		sshkey_free(k);
1376 		if (retval != 0)
1377 			break;
1378 		break;
1379 	default:
1380 		return SSH_ERR_INVALID_ARGUMENT;
1381 	}
1382 	return retval;
1383 }
1384 
1385 int
1386 sshkey_to_base64(const struct sshkey *key, char **b64p)
1387 {
1388 	int r = SSH_ERR_INTERNAL_ERROR;
1389 	struct sshbuf *b = NULL;
1390 	char *uu = NULL;
1391 
1392 	if (b64p != NULL)
1393 		*b64p = NULL;
1394 	if ((b = sshbuf_new()) == NULL)
1395 		return SSH_ERR_ALLOC_FAIL;
1396 	if ((r = sshkey_putb(key, b)) != 0)
1397 		goto out;
1398 	if ((uu = sshbuf_dtob64(b)) == NULL) {
1399 		r = SSH_ERR_ALLOC_FAIL;
1400 		goto out;
1401 	}
1402 	/* Success */
1403 	if (b64p != NULL) {
1404 		*b64p = uu;
1405 		uu = NULL;
1406 	}
1407 	r = 0;
1408  out:
1409 	sshbuf_free(b);
1410 	free(uu);
1411 	return r;
1412 }
1413 
1414 static int
1415 sshkey_format_rsa1(const struct sshkey *key, struct sshbuf *b)
1416 {
1417 	int r = SSH_ERR_INTERNAL_ERROR;
1418 #ifdef WITH_SSH1
1419 	u_int bits = 0;
1420 	char *dec_e = NULL, *dec_n = NULL;
1421 
1422 	if (key->rsa == NULL || key->rsa->e == NULL ||
1423 	    key->rsa->n == NULL) {
1424 		r = SSH_ERR_INVALID_ARGUMENT;
1425 		goto out;
1426 	}
1427 	if ((dec_e = BN_bn2dec(key->rsa->e)) == NULL ||
1428 	    (dec_n = BN_bn2dec(key->rsa->n)) == NULL) {
1429 		r = SSH_ERR_ALLOC_FAIL;
1430 		goto out;
1431 	}
1432 	/* size of modulus 'n' */
1433 	if ((bits = BN_num_bits(key->rsa->n)) <= 0) {
1434 		r = SSH_ERR_INVALID_ARGUMENT;
1435 		goto out;
1436 	}
1437 	if ((r = sshbuf_putf(b, "%u %s %s", bits, dec_e, dec_n)) != 0)
1438 		goto out;
1439 
1440 	/* Success */
1441 	r = 0;
1442  out:
1443 	if (dec_e != NULL)
1444 		OPENSSL_free(dec_e);
1445 	if (dec_n != NULL)
1446 		OPENSSL_free(dec_n);
1447 #endif /* WITH_SSH1 */
1448 
1449 	return r;
1450 }
1451 
1452 static int
1453 sshkey_format_text(const struct sshkey *key, struct sshbuf *b)
1454 {
1455 	int r = SSH_ERR_INTERNAL_ERROR;
1456 	char *uu = NULL;
1457 
1458 	if (key->type == KEY_RSA1) {
1459 		if ((r = sshkey_format_rsa1(key, b)) != 0)
1460 			goto out;
1461 	} else {
1462 		/* Unsupported key types handled in sshkey_to_base64() */
1463 		if ((r = sshkey_to_base64(key, &uu)) != 0)
1464 			goto out;
1465 		if ((r = sshbuf_putf(b, "%s %s",
1466 		    sshkey_ssh_name(key), uu)) != 0)
1467 			goto out;
1468 	}
1469 	r = 0;
1470  out:
1471 	free(uu);
1472 	return r;
1473 }
1474 
1475 int
1476 sshkey_write(const struct sshkey *key, FILE *f)
1477 {
1478 	struct sshbuf *b = NULL;
1479 	int r = SSH_ERR_INTERNAL_ERROR;
1480 
1481 	if ((b = sshbuf_new()) == NULL)
1482 		return SSH_ERR_ALLOC_FAIL;
1483 	if ((r = sshkey_format_text(key, b)) != 0)
1484 		goto out;
1485 	if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) {
1486 		if (feof(f))
1487 			errno = EPIPE;
1488 		r = SSH_ERR_SYSTEM_ERROR;
1489 		goto out;
1490 	}
1491 	/* Success */
1492 	r = 0;
1493  out:
1494 	sshbuf_free(b);
1495 	return r;
1496 }
1497 
1498 const char *
1499 sshkey_cert_type(const struct sshkey *k)
1500 {
1501 	switch (k->cert->type) {
1502 	case SSH2_CERT_TYPE_USER:
1503 		return "user";
1504 	case SSH2_CERT_TYPE_HOST:
1505 		return "host";
1506 	default:
1507 		return "unknown";
1508 	}
1509 }
1510 
1511 #ifdef WITH_OPENSSL
1512 static int
1513 rsa_generate_private_key(u_int bits, RSA **rsap)
1514 {
1515 	RSA *private = NULL;
1516 	BIGNUM *f4 = NULL;
1517 	int ret = SSH_ERR_INTERNAL_ERROR;
1518 
1519 	if (rsap == NULL ||
1520 	    bits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
1521 	    bits > SSHBUF_MAX_BIGNUM * 8)
1522 		return SSH_ERR_INVALID_ARGUMENT;
1523 	*rsap = NULL;
1524 	if ((private = RSA_new()) == NULL || (f4 = BN_new()) == NULL) {
1525 		ret = SSH_ERR_ALLOC_FAIL;
1526 		goto out;
1527 	}
1528 	if (!BN_set_word(f4, RSA_F4) ||
1529 	    !RSA_generate_key_ex(private, bits, f4, NULL)) {
1530 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1531 		goto out;
1532 	}
1533 	*rsap = private;
1534 	private = NULL;
1535 	ret = 0;
1536  out:
1537 	if (private != NULL)
1538 		RSA_free(private);
1539 	if (f4 != NULL)
1540 		BN_free(f4);
1541 	return ret;
1542 }
1543 
1544 static int
1545 dsa_generate_private_key(u_int bits, DSA **dsap)
1546 {
1547 	DSA *private;
1548 	int ret = SSH_ERR_INTERNAL_ERROR;
1549 
1550 	if (dsap == NULL || bits != 1024)
1551 		return SSH_ERR_INVALID_ARGUMENT;
1552 	if ((private = DSA_new()) == NULL) {
1553 		ret = SSH_ERR_ALLOC_FAIL;
1554 		goto out;
1555 	}
1556 	*dsap = NULL;
1557 	if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL,
1558 	    NULL, NULL) || !DSA_generate_key(private)) {
1559 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1560 		goto out;
1561 	}
1562 	*dsap = private;
1563 	private = NULL;
1564 	ret = 0;
1565  out:
1566 	if (private != NULL)
1567 		DSA_free(private);
1568 	return ret;
1569 }
1570 
1571 # ifdef OPENSSL_HAS_ECC
1572 int
1573 sshkey_ecdsa_key_to_nid(EC_KEY *k)
1574 {
1575 	EC_GROUP *eg;
1576 	int nids[] = {
1577 		NID_X9_62_prime256v1,
1578 		NID_secp384r1,
1579 #  ifdef OPENSSL_HAS_NISTP521
1580 		NID_secp521r1,
1581 #  endif /* OPENSSL_HAS_NISTP521 */
1582 		-1
1583 	};
1584 	int nid;
1585 	u_int i;
1586 	BN_CTX *bnctx;
1587 	const EC_GROUP *g = EC_KEY_get0_group(k);
1588 
1589 	/*
1590 	 * The group may be stored in a ASN.1 encoded private key in one of two
1591 	 * ways: as a "named group", which is reconstituted by ASN.1 object ID
1592 	 * or explicit group parameters encoded into the key blob. Only the
1593 	 * "named group" case sets the group NID for us, but we can figure
1594 	 * it out for the other case by comparing against all the groups that
1595 	 * are supported.
1596 	 */
1597 	if ((nid = EC_GROUP_get_curve_name(g)) > 0)
1598 		return nid;
1599 	if ((bnctx = BN_CTX_new()) == NULL)
1600 		return -1;
1601 	for (i = 0; nids[i] != -1; i++) {
1602 		if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL) {
1603 			BN_CTX_free(bnctx);
1604 			return -1;
1605 		}
1606 		if (EC_GROUP_cmp(g, eg, bnctx) == 0)
1607 			break;
1608 		EC_GROUP_free(eg);
1609 	}
1610 	BN_CTX_free(bnctx);
1611 	if (nids[i] != -1) {
1612 		/* Use the group with the NID attached */
1613 		EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
1614 		if (EC_KEY_set_group(k, eg) != 1) {
1615 			EC_GROUP_free(eg);
1616 			return -1;
1617 		}
1618 	}
1619 	return nids[i];
1620 }
1621 
1622 static int
1623 ecdsa_generate_private_key(u_int bits, int *nid, EC_KEY **ecdsap)
1624 {
1625 	EC_KEY *private;
1626 	int ret = SSH_ERR_INTERNAL_ERROR;
1627 
1628 	if (nid == NULL || ecdsap == NULL ||
1629 	    (*nid = sshkey_ecdsa_bits_to_nid(bits)) == -1)
1630 		return SSH_ERR_INVALID_ARGUMENT;
1631 	*ecdsap = NULL;
1632 	if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL) {
1633 		ret = SSH_ERR_ALLOC_FAIL;
1634 		goto out;
1635 	}
1636 	if (EC_KEY_generate_key(private) != 1) {
1637 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1638 		goto out;
1639 	}
1640 	EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE);
1641 	*ecdsap = private;
1642 	private = NULL;
1643 	ret = 0;
1644  out:
1645 	if (private != NULL)
1646 		EC_KEY_free(private);
1647 	return ret;
1648 }
1649 # endif /* OPENSSL_HAS_ECC */
1650 #endif /* WITH_OPENSSL */
1651 
1652 int
1653 sshkey_generate(int type, u_int bits, struct sshkey **keyp)
1654 {
1655 	struct sshkey *k;
1656 	int ret = SSH_ERR_INTERNAL_ERROR;
1657 
1658 	if (keyp == NULL)
1659 		return SSH_ERR_INVALID_ARGUMENT;
1660 	*keyp = NULL;
1661 	if ((k = sshkey_new(KEY_UNSPEC)) == NULL)
1662 		return SSH_ERR_ALLOC_FAIL;
1663 	switch (type) {
1664 	case KEY_ED25519:
1665 		if ((k->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL ||
1666 		    (k->ed25519_sk = malloc(ED25519_SK_SZ)) == NULL) {
1667 			ret = SSH_ERR_ALLOC_FAIL;
1668 			break;
1669 		}
1670 		crypto_sign_ed25519_keypair(k->ed25519_pk, k->ed25519_sk);
1671 		ret = 0;
1672 		break;
1673 #ifdef WITH_OPENSSL
1674 	case KEY_DSA:
1675 		ret = dsa_generate_private_key(bits, &k->dsa);
1676 		break;
1677 # ifdef OPENSSL_HAS_ECC
1678 	case KEY_ECDSA:
1679 		ret = ecdsa_generate_private_key(bits, &k->ecdsa_nid,
1680 		    &k->ecdsa);
1681 		break;
1682 # endif /* OPENSSL_HAS_ECC */
1683 	case KEY_RSA:
1684 	case KEY_RSA1:
1685 		ret = rsa_generate_private_key(bits, &k->rsa);
1686 		break;
1687 #endif /* WITH_OPENSSL */
1688 	default:
1689 		ret = SSH_ERR_INVALID_ARGUMENT;
1690 	}
1691 	if (ret == 0) {
1692 		k->type = type;
1693 		*keyp = k;
1694 	} else
1695 		sshkey_free(k);
1696 	return ret;
1697 }
1698 
1699 int
1700 sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key)
1701 {
1702 	u_int i;
1703 	const struct sshkey_cert *from;
1704 	struct sshkey_cert *to;
1705 	int ret = SSH_ERR_INTERNAL_ERROR;
1706 
1707 	if (to_key->cert != NULL) {
1708 		cert_free(to_key->cert);
1709 		to_key->cert = NULL;
1710 	}
1711 
1712 	if ((from = from_key->cert) == NULL)
1713 		return SSH_ERR_INVALID_ARGUMENT;
1714 
1715 	if ((to = to_key->cert = cert_new()) == NULL)
1716 		return SSH_ERR_ALLOC_FAIL;
1717 
1718 	if ((ret = sshbuf_putb(to->certblob, from->certblob)) != 0 ||
1719 	    (ret = sshbuf_putb(to->critical, from->critical)) != 0 ||
1720 	    (ret = sshbuf_putb(to->extensions, from->extensions) != 0))
1721 		return ret;
1722 
1723 	to->serial = from->serial;
1724 	to->type = from->type;
1725 	if (from->key_id == NULL)
1726 		to->key_id = NULL;
1727 	else if ((to->key_id = strdup(from->key_id)) == NULL)
1728 		return SSH_ERR_ALLOC_FAIL;
1729 	to->valid_after = from->valid_after;
1730 	to->valid_before = from->valid_before;
1731 	if (from->signature_key == NULL)
1732 		to->signature_key = NULL;
1733 	else if ((ret = sshkey_from_private(from->signature_key,
1734 	    &to->signature_key)) != 0)
1735 		return ret;
1736 
1737 	if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS)
1738 		return SSH_ERR_INVALID_ARGUMENT;
1739 	if (from->nprincipals > 0) {
1740 		if ((to->principals = calloc(from->nprincipals,
1741 		    sizeof(*to->principals))) == NULL)
1742 			return SSH_ERR_ALLOC_FAIL;
1743 		for (i = 0; i < from->nprincipals; i++) {
1744 			to->principals[i] = strdup(from->principals[i]);
1745 			if (to->principals[i] == NULL) {
1746 				to->nprincipals = i;
1747 				return SSH_ERR_ALLOC_FAIL;
1748 			}
1749 		}
1750 	}
1751 	to->nprincipals = from->nprincipals;
1752 	return 0;
1753 }
1754 
1755 int
1756 sshkey_from_private(const struct sshkey *k, struct sshkey **pkp)
1757 {
1758 	struct sshkey *n = NULL;
1759 	int ret = SSH_ERR_INTERNAL_ERROR;
1760 
1761 	if (pkp != NULL)
1762 		*pkp = NULL;
1763 
1764 	switch (k->type) {
1765 #ifdef WITH_OPENSSL
1766 	case KEY_DSA:
1767 	case KEY_DSA_CERT:
1768 		if ((n = sshkey_new(k->type)) == NULL)
1769 			return SSH_ERR_ALLOC_FAIL;
1770 		if ((BN_copy(n->dsa->p, k->dsa->p) == NULL) ||
1771 		    (BN_copy(n->dsa->q, k->dsa->q) == NULL) ||
1772 		    (BN_copy(n->dsa->g, k->dsa->g) == NULL) ||
1773 		    (BN_copy(n->dsa->pub_key, k->dsa->pub_key) == NULL)) {
1774 			sshkey_free(n);
1775 			return SSH_ERR_ALLOC_FAIL;
1776 		}
1777 		break;
1778 # ifdef OPENSSL_HAS_ECC
1779 	case KEY_ECDSA:
1780 	case KEY_ECDSA_CERT:
1781 		if ((n = sshkey_new(k->type)) == NULL)
1782 			return SSH_ERR_ALLOC_FAIL;
1783 		n->ecdsa_nid = k->ecdsa_nid;
1784 		n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
1785 		if (n->ecdsa == NULL) {
1786 			sshkey_free(n);
1787 			return SSH_ERR_ALLOC_FAIL;
1788 		}
1789 		if (EC_KEY_set_public_key(n->ecdsa,
1790 		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
1791 			sshkey_free(n);
1792 			return SSH_ERR_LIBCRYPTO_ERROR;
1793 		}
1794 		break;
1795 # endif /* OPENSSL_HAS_ECC */
1796 	case KEY_RSA:
1797 	case KEY_RSA1:
1798 	case KEY_RSA_CERT:
1799 		if ((n = sshkey_new(k->type)) == NULL)
1800 			return SSH_ERR_ALLOC_FAIL;
1801 		if ((BN_copy(n->rsa->n, k->rsa->n) == NULL) ||
1802 		    (BN_copy(n->rsa->e, k->rsa->e) == NULL)) {
1803 			sshkey_free(n);
1804 			return SSH_ERR_ALLOC_FAIL;
1805 		}
1806 		break;
1807 #endif /* WITH_OPENSSL */
1808 	case KEY_ED25519:
1809 	case KEY_ED25519_CERT:
1810 		if ((n = sshkey_new(k->type)) == NULL)
1811 			return SSH_ERR_ALLOC_FAIL;
1812 		if (k->ed25519_pk != NULL) {
1813 			if ((n->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
1814 				sshkey_free(n);
1815 				return SSH_ERR_ALLOC_FAIL;
1816 			}
1817 			memcpy(n->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
1818 		}
1819 		break;
1820 	default:
1821 		return SSH_ERR_KEY_TYPE_UNKNOWN;
1822 	}
1823 	if (sshkey_is_cert(k)) {
1824 		if ((ret = sshkey_cert_copy(k, n)) != 0) {
1825 			sshkey_free(n);
1826 			return ret;
1827 		}
1828 	}
1829 	*pkp = n;
1830 	return 0;
1831 }
1832 
1833 static int
1834 cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
1835 {
1836 	struct sshbuf *principals = NULL, *crit = NULL;
1837 	struct sshbuf *exts = NULL, *ca = NULL;
1838 	u_char *sig = NULL;
1839 	size_t signed_len = 0, slen = 0, kidlen = 0;
1840 	int ret = SSH_ERR_INTERNAL_ERROR;
1841 
1842 	/* Copy the entire key blob for verification and later serialisation */
1843 	if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0)
1844 		return ret;
1845 
1846 	/* Parse body of certificate up to signature */
1847 	if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 ||
1848 	    (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 ||
1849 	    (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 ||
1850 	    (ret = sshbuf_froms(b, &principals)) != 0 ||
1851 	    (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 ||
1852 	    (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 ||
1853 	    (ret = sshbuf_froms(b, &crit)) != 0 ||
1854 	    (ret = sshbuf_froms(b, &exts)) != 0 ||
1855 	    (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 ||
1856 	    (ret = sshbuf_froms(b, &ca)) != 0) {
1857 		/* XXX debug print error for ret */
1858 		ret = SSH_ERR_INVALID_FORMAT;
1859 		goto out;
1860 	}
1861 
1862 	/* Signature is left in the buffer so we can calculate this length */
1863 	signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b);
1864 
1865 	if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) {
1866 		ret = SSH_ERR_INVALID_FORMAT;
1867 		goto out;
1868 	}
1869 
1870 	if (key->cert->type != SSH2_CERT_TYPE_USER &&
1871 	    key->cert->type != SSH2_CERT_TYPE_HOST) {
1872 		ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE;
1873 		goto out;
1874 	}
1875 
1876 	/* Parse principals section */
1877 	while (sshbuf_len(principals) > 0) {
1878 		char *principal = NULL;
1879 		char **oprincipals = NULL;
1880 
1881 		if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) {
1882 			ret = SSH_ERR_INVALID_FORMAT;
1883 			goto out;
1884 		}
1885 		if ((ret = sshbuf_get_cstring(principals, &principal,
1886 		    NULL)) != 0) {
1887 			ret = SSH_ERR_INVALID_FORMAT;
1888 			goto out;
1889 		}
1890 		oprincipals = key->cert->principals;
1891 		key->cert->principals = reallocarray(key->cert->principals,
1892 		    key->cert->nprincipals + 1, sizeof(*key->cert->principals));
1893 		if (key->cert->principals == NULL) {
1894 			free(principal);
1895 			key->cert->principals = oprincipals;
1896 			ret = SSH_ERR_ALLOC_FAIL;
1897 			goto out;
1898 		}
1899 		key->cert->principals[key->cert->nprincipals++] = principal;
1900 	}
1901 
1902 	/*
1903 	 * Stash a copies of the critical options and extensions sections
1904 	 * for later use.
1905 	 */
1906 	if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 ||
1907 	    (exts != NULL &&
1908 	    (ret = sshbuf_putb(key->cert->extensions, exts)) != 0))
1909 		goto out;
1910 
1911 	/*
1912 	 * Validate critical options and extensions sections format.
1913 	 */
1914 	while (sshbuf_len(crit) != 0) {
1915 		if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 ||
1916 		    (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) {
1917 			sshbuf_reset(key->cert->critical);
1918 			ret = SSH_ERR_INVALID_FORMAT;
1919 			goto out;
1920 		}
1921 	}
1922 	while (exts != NULL && sshbuf_len(exts) != 0) {
1923 		if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 ||
1924 		    (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) {
1925 			sshbuf_reset(key->cert->extensions);
1926 			ret = SSH_ERR_INVALID_FORMAT;
1927 			goto out;
1928 		}
1929 	}
1930 
1931 	/* Parse CA key and check signature */
1932 	if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) {
1933 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1934 		goto out;
1935 	}
1936 	if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) {
1937 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1938 		goto out;
1939 	}
1940 	if ((ret = sshkey_verify(key->cert->signature_key, sig, slen,
1941 	    sshbuf_ptr(key->cert->certblob), signed_len, 0)) != 0)
1942 		goto out;
1943 
1944 	/* Success */
1945 	ret = 0;
1946  out:
1947 	sshbuf_free(ca);
1948 	sshbuf_free(crit);
1949 	sshbuf_free(exts);
1950 	sshbuf_free(principals);
1951 	free(sig);
1952 	return ret;
1953 }
1954 
1955 static int
1956 sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
1957     int allow_cert)
1958 {
1959 	int type, ret = SSH_ERR_INTERNAL_ERROR;
1960 	char *ktype = NULL, *curve = NULL;
1961 	struct sshkey *key = NULL;
1962 	size_t len;
1963 	u_char *pk = NULL;
1964 	struct sshbuf *copy;
1965 #if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
1966 	EC_POINT *q = NULL;
1967 #endif /* WITH_OPENSSL && OPENSSL_HAS_ECC */
1968 
1969 #ifdef DEBUG_PK /* XXX */
1970 	sshbuf_dump(b, stderr);
1971 #endif
1972 	*keyp = NULL;
1973 	if ((copy = sshbuf_fromb(b)) == NULL) {
1974 		ret = SSH_ERR_ALLOC_FAIL;
1975 		goto out;
1976 	}
1977 	if (sshbuf_get_cstring(b, &ktype, NULL) != 0) {
1978 		ret = SSH_ERR_INVALID_FORMAT;
1979 		goto out;
1980 	}
1981 
1982 	type = sshkey_type_from_name(ktype);
1983 	if (!allow_cert && sshkey_type_is_cert(type)) {
1984 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1985 		goto out;
1986 	}
1987 	switch (type) {
1988 #ifdef WITH_OPENSSL
1989 	case KEY_RSA_CERT:
1990 		/* Skip nonce */
1991 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
1992 			ret = SSH_ERR_INVALID_FORMAT;
1993 			goto out;
1994 		}
1995 		/* FALLTHROUGH */
1996 	case KEY_RSA:
1997 		if ((key = sshkey_new(type)) == NULL) {
1998 			ret = SSH_ERR_ALLOC_FAIL;
1999 			goto out;
2000 		}
2001 		if (sshbuf_get_bignum2(b, key->rsa->e) != 0 ||
2002 		    sshbuf_get_bignum2(b, key->rsa->n) != 0) {
2003 			ret = SSH_ERR_INVALID_FORMAT;
2004 			goto out;
2005 		}
2006 #ifdef DEBUG_PK
2007 		RSA_print_fp(stderr, key->rsa, 8);
2008 #endif
2009 		break;
2010 	case KEY_DSA_CERT:
2011 		/* Skip nonce */
2012 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2013 			ret = SSH_ERR_INVALID_FORMAT;
2014 			goto out;
2015 		}
2016 		/* FALLTHROUGH */
2017 	case KEY_DSA:
2018 		if ((key = sshkey_new(type)) == NULL) {
2019 			ret = SSH_ERR_ALLOC_FAIL;
2020 			goto out;
2021 		}
2022 		if (sshbuf_get_bignum2(b, key->dsa->p) != 0 ||
2023 		    sshbuf_get_bignum2(b, key->dsa->q) != 0 ||
2024 		    sshbuf_get_bignum2(b, key->dsa->g) != 0 ||
2025 		    sshbuf_get_bignum2(b, key->dsa->pub_key) != 0) {
2026 			ret = SSH_ERR_INVALID_FORMAT;
2027 			goto out;
2028 		}
2029 #ifdef DEBUG_PK
2030 		DSA_print_fp(stderr, key->dsa, 8);
2031 #endif
2032 		break;
2033 	case KEY_ECDSA_CERT:
2034 		/* Skip nonce */
2035 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2036 			ret = SSH_ERR_INVALID_FORMAT;
2037 			goto out;
2038 		}
2039 		/* FALLTHROUGH */
2040 # ifdef OPENSSL_HAS_ECC
2041 	case KEY_ECDSA:
2042 		if ((key = sshkey_new(type)) == NULL) {
2043 			ret = SSH_ERR_ALLOC_FAIL;
2044 			goto out;
2045 		}
2046 		key->ecdsa_nid = sshkey_ecdsa_nid_from_name(ktype);
2047 		if (sshbuf_get_cstring(b, &curve, NULL) != 0) {
2048 			ret = SSH_ERR_INVALID_FORMAT;
2049 			goto out;
2050 		}
2051 		if (key->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
2052 			ret = SSH_ERR_EC_CURVE_MISMATCH;
2053 			goto out;
2054 		}
2055 		if (key->ecdsa != NULL)
2056 			EC_KEY_free(key->ecdsa);
2057 		if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
2058 		    == NULL) {
2059 			ret = SSH_ERR_EC_CURVE_INVALID;
2060 			goto out;
2061 		}
2062 		if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL) {
2063 			ret = SSH_ERR_ALLOC_FAIL;
2064 			goto out;
2065 		}
2066 		if (sshbuf_get_ec(b, q, EC_KEY_get0_group(key->ecdsa)) != 0) {
2067 			ret = SSH_ERR_INVALID_FORMAT;
2068 			goto out;
2069 		}
2070 		if (sshkey_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
2071 		    q) != 0) {
2072 			ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2073 			goto out;
2074 		}
2075 		if (EC_KEY_set_public_key(key->ecdsa, q) != 1) {
2076 			/* XXX assume it is a allocation error */
2077 			ret = SSH_ERR_ALLOC_FAIL;
2078 			goto out;
2079 		}
2080 #ifdef DEBUG_PK
2081 		sshkey_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
2082 #endif
2083 		break;
2084 # endif /* OPENSSL_HAS_ECC */
2085 #endif /* WITH_OPENSSL */
2086 	case KEY_ED25519_CERT:
2087 		/* Skip nonce */
2088 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2089 			ret = SSH_ERR_INVALID_FORMAT;
2090 			goto out;
2091 		}
2092 		/* FALLTHROUGH */
2093 	case KEY_ED25519:
2094 		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
2095 			goto out;
2096 		if (len != ED25519_PK_SZ) {
2097 			ret = SSH_ERR_INVALID_FORMAT;
2098 			goto out;
2099 		}
2100 		if ((key = sshkey_new(type)) == NULL) {
2101 			ret = SSH_ERR_ALLOC_FAIL;
2102 			goto out;
2103 		}
2104 		key->ed25519_pk = pk;
2105 		pk = NULL;
2106 		break;
2107 	case KEY_UNSPEC:
2108 		if ((key = sshkey_new(type)) == NULL) {
2109 			ret = SSH_ERR_ALLOC_FAIL;
2110 			goto out;
2111 		}
2112 		break;
2113 	default:
2114 		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
2115 		goto out;
2116 	}
2117 
2118 	/* Parse certificate potion */
2119 	if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0)
2120 		goto out;
2121 
2122 	if (key != NULL && sshbuf_len(b) != 0) {
2123 		ret = SSH_ERR_INVALID_FORMAT;
2124 		goto out;
2125 	}
2126 	ret = 0;
2127 	*keyp = key;
2128 	key = NULL;
2129  out:
2130 	sshbuf_free(copy);
2131 	sshkey_free(key);
2132 	free(ktype);
2133 	free(curve);
2134 	free(pk);
2135 #if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
2136 	if (q != NULL)
2137 		EC_POINT_free(q);
2138 #endif /* WITH_OPENSSL && OPENSSL_HAS_ECC */
2139 	return ret;
2140 }
2141 
2142 int
2143 sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp)
2144 {
2145 	struct sshbuf *b;
2146 	int r;
2147 
2148 	if ((b = sshbuf_from(blob, blen)) == NULL)
2149 		return SSH_ERR_ALLOC_FAIL;
2150 	r = sshkey_from_blob_internal(b, keyp, 1);
2151 	sshbuf_free(b);
2152 	return r;
2153 }
2154 
2155 int
2156 sshkey_fromb(struct sshbuf *b, struct sshkey **keyp)
2157 {
2158 	return sshkey_from_blob_internal(b, keyp, 1);
2159 }
2160 
2161 int
2162 sshkey_froms(struct sshbuf *buf, struct sshkey **keyp)
2163 {
2164 	struct sshbuf *b;
2165 	int r;
2166 
2167 	if ((r = sshbuf_froms(buf, &b)) != 0)
2168 		return r;
2169 	r = sshkey_from_blob_internal(b, keyp, 1);
2170 	sshbuf_free(b);
2171 	return r;
2172 }
2173 
2174 int
2175 sshkey_sign(const struct sshkey *key,
2176     u_char **sigp, size_t *lenp,
2177     const u_char *data, size_t datalen, u_int compat)
2178 {
2179 	if (sigp != NULL)
2180 		*sigp = NULL;
2181 	if (lenp != NULL)
2182 		*lenp = 0;
2183 	if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2184 		return SSH_ERR_INVALID_ARGUMENT;
2185 	switch (key->type) {
2186 #ifdef WITH_OPENSSL
2187 	case KEY_DSA_CERT:
2188 	case KEY_DSA:
2189 		return ssh_dss_sign(key, sigp, lenp, data, datalen, compat);
2190 # ifdef OPENSSL_HAS_ECC
2191 	case KEY_ECDSA_CERT:
2192 	case KEY_ECDSA:
2193 		return ssh_ecdsa_sign(key, sigp, lenp, data, datalen, compat);
2194 # endif /* OPENSSL_HAS_ECC */
2195 	case KEY_RSA_CERT:
2196 	case KEY_RSA:
2197 		return ssh_rsa_sign(key, sigp, lenp, data, datalen, compat);
2198 #endif /* WITH_OPENSSL */
2199 	case KEY_ED25519:
2200 	case KEY_ED25519_CERT:
2201 		return ssh_ed25519_sign(key, sigp, lenp, data, datalen, compat);
2202 	default:
2203 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2204 	}
2205 }
2206 
2207 /*
2208  * ssh_key_verify returns 0 for a correct signature  and < 0 on error.
2209  */
2210 int
2211 sshkey_verify(const struct sshkey *key,
2212     const u_char *sig, size_t siglen,
2213     const u_char *data, size_t dlen, u_int compat)
2214 {
2215 	if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2216 		return SSH_ERR_INVALID_ARGUMENT;
2217 	switch (key->type) {
2218 #ifdef WITH_OPENSSL
2219 	case KEY_DSA_CERT:
2220 	case KEY_DSA:
2221 		return ssh_dss_verify(key, sig, siglen, data, dlen, compat);
2222 # ifdef OPENSSL_HAS_ECC
2223 	case KEY_ECDSA_CERT:
2224 	case KEY_ECDSA:
2225 		return ssh_ecdsa_verify(key, sig, siglen, data, dlen, compat);
2226 # endif /* OPENSSL_HAS_ECC */
2227 	case KEY_RSA_CERT:
2228 	case KEY_RSA:
2229 		return ssh_rsa_verify(key, sig, siglen, data, dlen, compat);
2230 #endif /* WITH_OPENSSL */
2231 	case KEY_ED25519:
2232 	case KEY_ED25519_CERT:
2233 		return ssh_ed25519_verify(key, sig, siglen, data, dlen, compat);
2234 	default:
2235 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2236 	}
2237 }
2238 
2239 /* Converts a private to a public key */
2240 int
2241 sshkey_demote(const struct sshkey *k, struct sshkey **dkp)
2242 {
2243 	struct sshkey *pk;
2244 	int ret = SSH_ERR_INTERNAL_ERROR;
2245 
2246 	if (dkp != NULL)
2247 		*dkp = NULL;
2248 
2249 	if ((pk = calloc(1, sizeof(*pk))) == NULL)
2250 		return SSH_ERR_ALLOC_FAIL;
2251 	pk->type = k->type;
2252 	pk->flags = k->flags;
2253 	pk->ecdsa_nid = k->ecdsa_nid;
2254 	pk->dsa = NULL;
2255 	pk->ecdsa = NULL;
2256 	pk->rsa = NULL;
2257 	pk->ed25519_pk = NULL;
2258 	pk->ed25519_sk = NULL;
2259 
2260 	switch (k->type) {
2261 #ifdef WITH_OPENSSL
2262 	case KEY_RSA_CERT:
2263 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2264 			goto fail;
2265 		/* FALLTHROUGH */
2266 	case KEY_RSA1:
2267 	case KEY_RSA:
2268 		if ((pk->rsa = RSA_new()) == NULL ||
2269 		    (pk->rsa->e = BN_dup(k->rsa->e)) == NULL ||
2270 		    (pk->rsa->n = BN_dup(k->rsa->n)) == NULL) {
2271 			ret = SSH_ERR_ALLOC_FAIL;
2272 			goto fail;
2273 			}
2274 		break;
2275 	case KEY_DSA_CERT:
2276 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2277 			goto fail;
2278 		/* FALLTHROUGH */
2279 	case KEY_DSA:
2280 		if ((pk->dsa = DSA_new()) == NULL ||
2281 		    (pk->dsa->p = BN_dup(k->dsa->p)) == NULL ||
2282 		    (pk->dsa->q = BN_dup(k->dsa->q)) == NULL ||
2283 		    (pk->dsa->g = BN_dup(k->dsa->g)) == NULL ||
2284 		    (pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL) {
2285 			ret = SSH_ERR_ALLOC_FAIL;
2286 			goto fail;
2287 		}
2288 		break;
2289 	case KEY_ECDSA_CERT:
2290 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2291 			goto fail;
2292 		/* FALLTHROUGH */
2293 # ifdef OPENSSL_HAS_ECC
2294 	case KEY_ECDSA:
2295 		pk->ecdsa = EC_KEY_new_by_curve_name(pk->ecdsa_nid);
2296 		if (pk->ecdsa == NULL) {
2297 			ret = SSH_ERR_ALLOC_FAIL;
2298 			goto fail;
2299 		}
2300 		if (EC_KEY_set_public_key(pk->ecdsa,
2301 		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
2302 			ret = SSH_ERR_LIBCRYPTO_ERROR;
2303 			goto fail;
2304 		}
2305 		break;
2306 # endif /* OPENSSL_HAS_ECC */
2307 #endif /* WITH_OPENSSL */
2308 	case KEY_ED25519_CERT:
2309 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2310 			goto fail;
2311 		/* FALLTHROUGH */
2312 	case KEY_ED25519:
2313 		if (k->ed25519_pk != NULL) {
2314 			if ((pk->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
2315 				ret = SSH_ERR_ALLOC_FAIL;
2316 				goto fail;
2317 			}
2318 			memcpy(pk->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
2319 		}
2320 		break;
2321 	default:
2322 		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
2323  fail:
2324 		sshkey_free(pk);
2325 		return ret;
2326 	}
2327 	*dkp = pk;
2328 	return 0;
2329 }
2330 
2331 /* Convert a plain key to their _CERT equivalent */
2332 int
2333 sshkey_to_certified(struct sshkey *k)
2334 {
2335 	int newtype;
2336 
2337 	switch (k->type) {
2338 #ifdef WITH_OPENSSL
2339 	case KEY_RSA:
2340 		newtype = KEY_RSA_CERT;
2341 		break;
2342 	case KEY_DSA:
2343 		newtype = KEY_DSA_CERT;
2344 		break;
2345 	case KEY_ECDSA:
2346 		newtype = KEY_ECDSA_CERT;
2347 		break;
2348 #endif /* WITH_OPENSSL */
2349 	case KEY_ED25519:
2350 		newtype = KEY_ED25519_CERT;
2351 		break;
2352 	default:
2353 		return SSH_ERR_INVALID_ARGUMENT;
2354 	}
2355 	if ((k->cert = cert_new()) == NULL)
2356 		return SSH_ERR_ALLOC_FAIL;
2357 	k->type = newtype;
2358 	return 0;
2359 }
2360 
2361 /* Convert a certificate to its raw key equivalent */
2362 int
2363 sshkey_drop_cert(struct sshkey *k)
2364 {
2365 	if (!sshkey_type_is_cert(k->type))
2366 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2367 	cert_free(k->cert);
2368 	k->cert = NULL;
2369 	k->type = sshkey_type_plain(k->type);
2370 	return 0;
2371 }
2372 
2373 /* Sign a certified key, (re-)generating the signed certblob. */
2374 int
2375 sshkey_certify(struct sshkey *k, struct sshkey *ca)
2376 {
2377 	struct sshbuf *principals = NULL;
2378 	u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32];
2379 	size_t i, ca_len, sig_len;
2380 	int ret = SSH_ERR_INTERNAL_ERROR;
2381 	struct sshbuf *cert;
2382 
2383 	if (k == NULL || k->cert == NULL ||
2384 	    k->cert->certblob == NULL || ca == NULL)
2385 		return SSH_ERR_INVALID_ARGUMENT;
2386 	if (!sshkey_is_cert(k))
2387 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2388 	if (!sshkey_type_is_valid_ca(ca->type))
2389 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2390 
2391 	if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0)
2392 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2393 
2394 	cert = k->cert->certblob; /* for readability */
2395 	sshbuf_reset(cert);
2396 	if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0)
2397 		goto out;
2398 
2399 	/* -v01 certs put nonce first */
2400 	arc4random_buf(&nonce, sizeof(nonce));
2401 	if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0)
2402 		goto out;
2403 
2404 	/* XXX this substantially duplicates to_blob(); refactor */
2405 	switch (k->type) {
2406 #ifdef WITH_OPENSSL
2407 	case KEY_DSA_CERT:
2408 		if ((ret = sshbuf_put_bignum2(cert, k->dsa->p)) != 0 ||
2409 		    (ret = sshbuf_put_bignum2(cert, k->dsa->q)) != 0 ||
2410 		    (ret = sshbuf_put_bignum2(cert, k->dsa->g)) != 0 ||
2411 		    (ret = sshbuf_put_bignum2(cert, k->dsa->pub_key)) != 0)
2412 			goto out;
2413 		break;
2414 # ifdef OPENSSL_HAS_ECC
2415 	case KEY_ECDSA_CERT:
2416 		if ((ret = sshbuf_put_cstring(cert,
2417 		    sshkey_curve_nid_to_name(k->ecdsa_nid))) != 0 ||
2418 		    (ret = sshbuf_put_ec(cert,
2419 		    EC_KEY_get0_public_key(k->ecdsa),
2420 		    EC_KEY_get0_group(k->ecdsa))) != 0)
2421 			goto out;
2422 		break;
2423 # endif /* OPENSSL_HAS_ECC */
2424 	case KEY_RSA_CERT:
2425 		if ((ret = sshbuf_put_bignum2(cert, k->rsa->e)) != 0 ||
2426 		    (ret = sshbuf_put_bignum2(cert, k->rsa->n)) != 0)
2427 			goto out;
2428 		break;
2429 #endif /* WITH_OPENSSL */
2430 	case KEY_ED25519_CERT:
2431 		if ((ret = sshbuf_put_string(cert,
2432 		    k->ed25519_pk, ED25519_PK_SZ)) != 0)
2433 			goto out;
2434 		break;
2435 	default:
2436 		ret = SSH_ERR_INVALID_ARGUMENT;
2437 		goto out;
2438 	}
2439 
2440 	if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 ||
2441 	    (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 ||
2442 	    (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0)
2443 		goto out;
2444 
2445 	if ((principals = sshbuf_new()) == NULL) {
2446 		ret = SSH_ERR_ALLOC_FAIL;
2447 		goto out;
2448 	}
2449 	for (i = 0; i < k->cert->nprincipals; i++) {
2450 		if ((ret = sshbuf_put_cstring(principals,
2451 		    k->cert->principals[i])) != 0)
2452 			goto out;
2453 	}
2454 	if ((ret = sshbuf_put_stringb(cert, principals)) != 0 ||
2455 	    (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 ||
2456 	    (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 ||
2457 	    (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 ||
2458 	    (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 ||
2459 	    (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */
2460 	    (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0)
2461 		goto out;
2462 
2463 	/* Sign the whole mess */
2464 	if ((ret = sshkey_sign(ca, &sig_blob, &sig_len, sshbuf_ptr(cert),
2465 	    sshbuf_len(cert), 0)) != 0)
2466 		goto out;
2467 
2468 	/* Append signature and we are done */
2469 	if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0)
2470 		goto out;
2471 	ret = 0;
2472  out:
2473 	if (ret != 0)
2474 		sshbuf_reset(cert);
2475 	if (sig_blob != NULL)
2476 		free(sig_blob);
2477 	if (ca_blob != NULL)
2478 		free(ca_blob);
2479 	if (principals != NULL)
2480 		sshbuf_free(principals);
2481 	return ret;
2482 }
2483 
2484 int
2485 sshkey_cert_check_authority(const struct sshkey *k,
2486     int want_host, int require_principal,
2487     const char *name, const char **reason)
2488 {
2489 	u_int i, principal_matches;
2490 	time_t now = time(NULL);
2491 
2492 	if (reason != NULL)
2493 		*reason = NULL;
2494 
2495 	if (want_host) {
2496 		if (k->cert->type != SSH2_CERT_TYPE_HOST) {
2497 			*reason = "Certificate invalid: not a host certificate";
2498 			return SSH_ERR_KEY_CERT_INVALID;
2499 		}
2500 	} else {
2501 		if (k->cert->type != SSH2_CERT_TYPE_USER) {
2502 			*reason = "Certificate invalid: not a user certificate";
2503 			return SSH_ERR_KEY_CERT_INVALID;
2504 		}
2505 	}
2506 	if (now < 0) {
2507 		/* yikes - system clock before epoch! */
2508 		*reason = "Certificate invalid: not yet valid";
2509 		return SSH_ERR_KEY_CERT_INVALID;
2510 	}
2511 	if ((u_int64_t)now < k->cert->valid_after) {
2512 		*reason = "Certificate invalid: not yet valid";
2513 		return SSH_ERR_KEY_CERT_INVALID;
2514 	}
2515 	if ((u_int64_t)now >= k->cert->valid_before) {
2516 		*reason = "Certificate invalid: expired";
2517 		return SSH_ERR_KEY_CERT_INVALID;
2518 	}
2519 	if (k->cert->nprincipals == 0) {
2520 		if (require_principal) {
2521 			*reason = "Certificate lacks principal list";
2522 			return SSH_ERR_KEY_CERT_INVALID;
2523 		}
2524 	} else if (name != NULL) {
2525 		principal_matches = 0;
2526 		for (i = 0; i < k->cert->nprincipals; i++) {
2527 			if (strcmp(name, k->cert->principals[i]) == 0) {
2528 				principal_matches = 1;
2529 				break;
2530 			}
2531 		}
2532 		if (!principal_matches) {
2533 			*reason = "Certificate invalid: name is not a listed "
2534 			    "principal";
2535 			return SSH_ERR_KEY_CERT_INVALID;
2536 		}
2537 	}
2538 	return 0;
2539 }
2540 
2541 int
2542 sshkey_private_serialize(const struct sshkey *key, struct sshbuf *b)
2543 {
2544 	int r = SSH_ERR_INTERNAL_ERROR;
2545 
2546 	if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0)
2547 		goto out;
2548 	switch (key->type) {
2549 #ifdef WITH_OPENSSL
2550 	case KEY_RSA:
2551 		if ((r = sshbuf_put_bignum2(b, key->rsa->n)) != 0 ||
2552 		    (r = sshbuf_put_bignum2(b, key->rsa->e)) != 0 ||
2553 		    (r = sshbuf_put_bignum2(b, key->rsa->d)) != 0 ||
2554 		    (r = sshbuf_put_bignum2(b, key->rsa->iqmp)) != 0 ||
2555 		    (r = sshbuf_put_bignum2(b, key->rsa->p)) != 0 ||
2556 		    (r = sshbuf_put_bignum2(b, key->rsa->q)) != 0)
2557 			goto out;
2558 		break;
2559 	case KEY_RSA_CERT:
2560 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2561 			r = SSH_ERR_INVALID_ARGUMENT;
2562 			goto out;
2563 		}
2564 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2565 		    (r = sshbuf_put_bignum2(b, key->rsa->d)) != 0 ||
2566 		    (r = sshbuf_put_bignum2(b, key->rsa->iqmp)) != 0 ||
2567 		    (r = sshbuf_put_bignum2(b, key->rsa->p)) != 0 ||
2568 		    (r = sshbuf_put_bignum2(b, key->rsa->q)) != 0)
2569 			goto out;
2570 		break;
2571 	case KEY_DSA:
2572 		if ((r = sshbuf_put_bignum2(b, key->dsa->p)) != 0 ||
2573 		    (r = sshbuf_put_bignum2(b, key->dsa->q)) != 0 ||
2574 		    (r = sshbuf_put_bignum2(b, key->dsa->g)) != 0 ||
2575 		    (r = sshbuf_put_bignum2(b, key->dsa->pub_key)) != 0 ||
2576 		    (r = sshbuf_put_bignum2(b, key->dsa->priv_key)) != 0)
2577 			goto out;
2578 		break;
2579 	case KEY_DSA_CERT:
2580 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2581 			r = SSH_ERR_INVALID_ARGUMENT;
2582 			goto out;
2583 		}
2584 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2585 		    (r = sshbuf_put_bignum2(b, key->dsa->priv_key)) != 0)
2586 			goto out;
2587 		break;
2588 # ifdef OPENSSL_HAS_ECC
2589 	case KEY_ECDSA:
2590 		if ((r = sshbuf_put_cstring(b,
2591 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
2592 		    (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 ||
2593 		    (r = sshbuf_put_bignum2(b,
2594 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
2595 			goto out;
2596 		break;
2597 	case KEY_ECDSA_CERT:
2598 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2599 			r = SSH_ERR_INVALID_ARGUMENT;
2600 			goto out;
2601 		}
2602 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2603 		    (r = sshbuf_put_bignum2(b,
2604 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
2605 			goto out;
2606 		break;
2607 # endif /* OPENSSL_HAS_ECC */
2608 #endif /* WITH_OPENSSL */
2609 	case KEY_ED25519:
2610 		if ((r = sshbuf_put_string(b, key->ed25519_pk,
2611 		    ED25519_PK_SZ)) != 0 ||
2612 		    (r = sshbuf_put_string(b, key->ed25519_sk,
2613 		    ED25519_SK_SZ)) != 0)
2614 			goto out;
2615 		break;
2616 	case KEY_ED25519_CERT:
2617 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2618 			r = SSH_ERR_INVALID_ARGUMENT;
2619 			goto out;
2620 		}
2621 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2622 		    (r = sshbuf_put_string(b, key->ed25519_pk,
2623 		    ED25519_PK_SZ)) != 0 ||
2624 		    (r = sshbuf_put_string(b, key->ed25519_sk,
2625 		    ED25519_SK_SZ)) != 0)
2626 			goto out;
2627 		break;
2628 	default:
2629 		r = SSH_ERR_INVALID_ARGUMENT;
2630 		goto out;
2631 	}
2632 	/* success */
2633 	r = 0;
2634  out:
2635 	return r;
2636 }
2637 
2638 int
2639 sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
2640 {
2641 	char *tname = NULL, *curve = NULL;
2642 	struct sshkey *k = NULL;
2643 	size_t pklen = 0, sklen = 0;
2644 	int type, r = SSH_ERR_INTERNAL_ERROR;
2645 	u_char *ed25519_pk = NULL, *ed25519_sk = NULL;
2646 #ifdef WITH_OPENSSL
2647 	BIGNUM *exponent = NULL;
2648 #endif /* WITH_OPENSSL */
2649 
2650 	if (kp != NULL)
2651 		*kp = NULL;
2652 	if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0)
2653 		goto out;
2654 	type = sshkey_type_from_name(tname);
2655 	switch (type) {
2656 #ifdef WITH_OPENSSL
2657 	case KEY_DSA:
2658 		if ((k = sshkey_new_private(type)) == NULL) {
2659 			r = SSH_ERR_ALLOC_FAIL;
2660 			goto out;
2661 		}
2662 		if ((r = sshbuf_get_bignum2(buf, k->dsa->p)) != 0 ||
2663 		    (r = sshbuf_get_bignum2(buf, k->dsa->q)) != 0 ||
2664 		    (r = sshbuf_get_bignum2(buf, k->dsa->g)) != 0 ||
2665 		    (r = sshbuf_get_bignum2(buf, k->dsa->pub_key)) != 0 ||
2666 		    (r = sshbuf_get_bignum2(buf, k->dsa->priv_key)) != 0)
2667 			goto out;
2668 		break;
2669 	case KEY_DSA_CERT:
2670 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2671 		    (r = sshkey_add_private(k)) != 0 ||
2672 		    (r = sshbuf_get_bignum2(buf, k->dsa->priv_key)) != 0)
2673 			goto out;
2674 		break;
2675 # ifdef OPENSSL_HAS_ECC
2676 	case KEY_ECDSA:
2677 		if ((k = sshkey_new_private(type)) == NULL) {
2678 			r = SSH_ERR_ALLOC_FAIL;
2679 			goto out;
2680 		}
2681 		if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) {
2682 			r = SSH_ERR_INVALID_ARGUMENT;
2683 			goto out;
2684 		}
2685 		if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0)
2686 			goto out;
2687 		if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
2688 			r = SSH_ERR_EC_CURVE_MISMATCH;
2689 			goto out;
2690 		}
2691 		k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
2692 		if (k->ecdsa  == NULL || (exponent = BN_new()) == NULL) {
2693 			r = SSH_ERR_LIBCRYPTO_ERROR;
2694 			goto out;
2695 		}
2696 		if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0 ||
2697 		    (r = sshbuf_get_bignum2(buf, exponent)))
2698 			goto out;
2699 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
2700 			r = SSH_ERR_LIBCRYPTO_ERROR;
2701 			goto out;
2702 		}
2703 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
2704 		    EC_KEY_get0_public_key(k->ecdsa)) != 0) ||
2705 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
2706 			goto out;
2707 		break;
2708 	case KEY_ECDSA_CERT:
2709 		if ((exponent = BN_new()) == NULL) {
2710 			r = SSH_ERR_LIBCRYPTO_ERROR;
2711 			goto out;
2712 		}
2713 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2714 		    (r = sshkey_add_private(k)) != 0 ||
2715 		    (r = sshbuf_get_bignum2(buf, exponent)) != 0)
2716 			goto out;
2717 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
2718 			r = SSH_ERR_LIBCRYPTO_ERROR;
2719 			goto out;
2720 		}
2721 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
2722 		    EC_KEY_get0_public_key(k->ecdsa)) != 0) ||
2723 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
2724 			goto out;
2725 		break;
2726 # endif /* OPENSSL_HAS_ECC */
2727 	case KEY_RSA:
2728 		if ((k = sshkey_new_private(type)) == NULL) {
2729 			r = SSH_ERR_ALLOC_FAIL;
2730 			goto out;
2731 		}
2732 		if ((r = sshbuf_get_bignum2(buf, k->rsa->n)) != 0 ||
2733 		    (r = sshbuf_get_bignum2(buf, k->rsa->e)) != 0 ||
2734 		    (r = sshbuf_get_bignum2(buf, k->rsa->d)) != 0 ||
2735 		    (r = sshbuf_get_bignum2(buf, k->rsa->iqmp)) != 0 ||
2736 		    (r = sshbuf_get_bignum2(buf, k->rsa->p)) != 0 ||
2737 		    (r = sshbuf_get_bignum2(buf, k->rsa->q)) != 0 ||
2738 		    (r = rsa_generate_additional_parameters(k->rsa)) != 0)
2739 			goto out;
2740 		break;
2741 	case KEY_RSA_CERT:
2742 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2743 		    (r = sshkey_add_private(k)) != 0 ||
2744 		    (r = sshbuf_get_bignum2(buf, k->rsa->d) != 0) ||
2745 		    (r = sshbuf_get_bignum2(buf, k->rsa->iqmp) != 0) ||
2746 		    (r = sshbuf_get_bignum2(buf, k->rsa->p) != 0) ||
2747 		    (r = sshbuf_get_bignum2(buf, k->rsa->q) != 0) ||
2748 		    (r = rsa_generate_additional_parameters(k->rsa)) != 0)
2749 			goto out;
2750 		break;
2751 #endif /* WITH_OPENSSL */
2752 	case KEY_ED25519:
2753 		if ((k = sshkey_new_private(type)) == NULL) {
2754 			r = SSH_ERR_ALLOC_FAIL;
2755 			goto out;
2756 		}
2757 		if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
2758 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
2759 			goto out;
2760 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
2761 			r = SSH_ERR_INVALID_FORMAT;
2762 			goto out;
2763 		}
2764 		k->ed25519_pk = ed25519_pk;
2765 		k->ed25519_sk = ed25519_sk;
2766 		ed25519_pk = ed25519_sk = NULL;
2767 		break;
2768 	case KEY_ED25519_CERT:
2769 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2770 		    (r = sshkey_add_private(k)) != 0 ||
2771 		    (r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
2772 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
2773 			goto out;
2774 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
2775 			r = SSH_ERR_INVALID_FORMAT;
2776 			goto out;
2777 		}
2778 		k->ed25519_pk = ed25519_pk;
2779 		k->ed25519_sk = ed25519_sk;
2780 		ed25519_pk = ed25519_sk = NULL;
2781 		break;
2782 	default:
2783 		r = SSH_ERR_KEY_TYPE_UNKNOWN;
2784 		goto out;
2785 	}
2786 #ifdef WITH_OPENSSL
2787 	/* enable blinding */
2788 	switch (k->type) {
2789 	case KEY_RSA:
2790 	case KEY_RSA_CERT:
2791 	case KEY_RSA1:
2792 		if (RSA_blinding_on(k->rsa, NULL) != 1) {
2793 			r = SSH_ERR_LIBCRYPTO_ERROR;
2794 			goto out;
2795 		}
2796 		break;
2797 	}
2798 #endif /* WITH_OPENSSL */
2799 	/* success */
2800 	r = 0;
2801 	if (kp != NULL) {
2802 		*kp = k;
2803 		k = NULL;
2804 	}
2805  out:
2806 	free(tname);
2807 	free(curve);
2808 #ifdef WITH_OPENSSL
2809 	if (exponent != NULL)
2810 		BN_clear_free(exponent);
2811 #endif /* WITH_OPENSSL */
2812 	sshkey_free(k);
2813 	if (ed25519_pk != NULL) {
2814 		explicit_bzero(ed25519_pk, pklen);
2815 		free(ed25519_pk);
2816 	}
2817 	if (ed25519_sk != NULL) {
2818 		explicit_bzero(ed25519_sk, sklen);
2819 		free(ed25519_sk);
2820 	}
2821 	return r;
2822 }
2823 
2824 #if defined(WITH_OPENSSL) && defined(OPENSSL_HAS_ECC)
2825 int
2826 sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
2827 {
2828 	BN_CTX *bnctx;
2829 	EC_POINT *nq = NULL;
2830 	BIGNUM *order, *x, *y, *tmp;
2831 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2832 
2833 	if ((bnctx = BN_CTX_new()) == NULL)
2834 		return SSH_ERR_ALLOC_FAIL;
2835 	BN_CTX_start(bnctx);
2836 
2837 	/*
2838 	 * We shouldn't ever hit this case because bignum_get_ecpoint()
2839 	 * refuses to load GF2m points.
2840 	 */
2841 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2842 	    NID_X9_62_prime_field)
2843 		goto out;
2844 
2845 	/* Q != infinity */
2846 	if (EC_POINT_is_at_infinity(group, public))
2847 		goto out;
2848 
2849 	if ((x = BN_CTX_get(bnctx)) == NULL ||
2850 	    (y = BN_CTX_get(bnctx)) == NULL ||
2851 	    (order = BN_CTX_get(bnctx)) == NULL ||
2852 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
2853 		ret = SSH_ERR_ALLOC_FAIL;
2854 		goto out;
2855 	}
2856 
2857 	/* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
2858 	if (EC_GROUP_get_order(group, order, bnctx) != 1 ||
2859 	    EC_POINT_get_affine_coordinates_GFp(group, public,
2860 	    x, y, bnctx) != 1) {
2861 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2862 		goto out;
2863 	}
2864 	if (BN_num_bits(x) <= BN_num_bits(order) / 2 ||
2865 	    BN_num_bits(y) <= BN_num_bits(order) / 2)
2866 		goto out;
2867 
2868 	/* nQ == infinity (n == order of subgroup) */
2869 	if ((nq = EC_POINT_new(group)) == NULL) {
2870 		ret = SSH_ERR_ALLOC_FAIL;
2871 		goto out;
2872 	}
2873 	if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1) {
2874 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2875 		goto out;
2876 	}
2877 	if (EC_POINT_is_at_infinity(group, nq) != 1)
2878 		goto out;
2879 
2880 	/* x < order - 1, y < order - 1 */
2881 	if (!BN_sub(tmp, order, BN_value_one())) {
2882 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2883 		goto out;
2884 	}
2885 	if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0)
2886 		goto out;
2887 	ret = 0;
2888  out:
2889 	BN_CTX_free(bnctx);
2890 	if (nq != NULL)
2891 		EC_POINT_free(nq);
2892 	return ret;
2893 }
2894 
2895 int
2896 sshkey_ec_validate_private(const EC_KEY *key)
2897 {
2898 	BN_CTX *bnctx;
2899 	BIGNUM *order, *tmp;
2900 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2901 
2902 	if ((bnctx = BN_CTX_new()) == NULL)
2903 		return SSH_ERR_ALLOC_FAIL;
2904 	BN_CTX_start(bnctx);
2905 
2906 	if ((order = BN_CTX_get(bnctx)) == NULL ||
2907 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
2908 		ret = SSH_ERR_ALLOC_FAIL;
2909 		goto out;
2910 	}
2911 
2912 	/* log2(private) > log2(order)/2 */
2913 	if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1) {
2914 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2915 		goto out;
2916 	}
2917 	if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
2918 	    BN_num_bits(order) / 2)
2919 		goto out;
2920 
2921 	/* private < order - 1 */
2922 	if (!BN_sub(tmp, order, BN_value_one())) {
2923 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2924 		goto out;
2925 	}
2926 	if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0)
2927 		goto out;
2928 	ret = 0;
2929  out:
2930 	BN_CTX_free(bnctx);
2931 	return ret;
2932 }
2933 
2934 void
2935 sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
2936 {
2937 	BIGNUM *x, *y;
2938 	BN_CTX *bnctx;
2939 
2940 	if (point == NULL) {
2941 		fputs("point=(NULL)\n", stderr);
2942 		return;
2943 	}
2944 	if ((bnctx = BN_CTX_new()) == NULL) {
2945 		fprintf(stderr, "%s: BN_CTX_new failed\n", __func__);
2946 		return;
2947 	}
2948 	BN_CTX_start(bnctx);
2949 	if ((x = BN_CTX_get(bnctx)) == NULL ||
2950 	    (y = BN_CTX_get(bnctx)) == NULL) {
2951 		fprintf(stderr, "%s: BN_CTX_get failed\n", __func__);
2952 		return;
2953 	}
2954 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2955 	    NID_X9_62_prime_field) {
2956 		fprintf(stderr, "%s: group is not a prime field\n", __func__);
2957 		return;
2958 	}
2959 	if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y,
2960 	    bnctx) != 1) {
2961 		fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n",
2962 		    __func__);
2963 		return;
2964 	}
2965 	fputs("x=", stderr);
2966 	BN_print_fp(stderr, x);
2967 	fputs("\ny=", stderr);
2968 	BN_print_fp(stderr, y);
2969 	fputs("\n", stderr);
2970 	BN_CTX_free(bnctx);
2971 }
2972 
2973 void
2974 sshkey_dump_ec_key(const EC_KEY *key)
2975 {
2976 	const BIGNUM *exponent;
2977 
2978 	sshkey_dump_ec_point(EC_KEY_get0_group(key),
2979 	    EC_KEY_get0_public_key(key));
2980 	fputs("exponent=", stderr);
2981 	if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
2982 		fputs("(NULL)", stderr);
2983 	else
2984 		BN_print_fp(stderr, EC_KEY_get0_private_key(key));
2985 	fputs("\n", stderr);
2986 }
2987 #endif /* WITH_OPENSSL && OPENSSL_HAS_ECC */
2988 
2989 static int
2990 sshkey_private_to_blob2(const struct sshkey *prv, struct sshbuf *blob,
2991     const char *passphrase, const char *comment, const char *ciphername,
2992     int rounds)
2993 {
2994 	u_char *cp, *key = NULL, *pubkeyblob = NULL;
2995 	u_char salt[SALT_LEN];
2996 	char *b64 = NULL;
2997 	size_t i, pubkeylen, keylen, ivlen, blocksize, authlen;
2998 	u_int check;
2999 	int r = SSH_ERR_INTERNAL_ERROR;
3000 	struct sshcipher_ctx ciphercontext;
3001 	const struct sshcipher *cipher;
3002 	const char *kdfname = KDFNAME;
3003 	struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL;
3004 
3005 	memset(&ciphercontext, 0, sizeof(ciphercontext));
3006 
3007 	if (rounds <= 0)
3008 		rounds = DEFAULT_ROUNDS;
3009 	if (passphrase == NULL || !strlen(passphrase)) {
3010 		ciphername = "none";
3011 		kdfname = "none";
3012 	} else if (ciphername == NULL)
3013 		ciphername = DEFAULT_CIPHERNAME;
3014 	else if (cipher_number(ciphername) != SSH_CIPHER_SSH2) {
3015 		r = SSH_ERR_INVALID_ARGUMENT;
3016 		goto out;
3017 	}
3018 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
3019 		r = SSH_ERR_INTERNAL_ERROR;
3020 		goto out;
3021 	}
3022 
3023 	if ((kdf = sshbuf_new()) == NULL ||
3024 	    (encoded = sshbuf_new()) == NULL ||
3025 	    (encrypted = sshbuf_new()) == NULL) {
3026 		r = SSH_ERR_ALLOC_FAIL;
3027 		goto out;
3028 	}
3029 	blocksize = cipher_blocksize(cipher);
3030 	keylen = cipher_keylen(cipher);
3031 	ivlen = cipher_ivlen(cipher);
3032 	authlen = cipher_authlen(cipher);
3033 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
3034 		r = SSH_ERR_ALLOC_FAIL;
3035 		goto out;
3036 	}
3037 	if (strcmp(kdfname, "bcrypt") == 0) {
3038 		arc4random_buf(salt, SALT_LEN);
3039 		if (bcrypt_pbkdf(passphrase, strlen(passphrase),
3040 		    salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) {
3041 			r = SSH_ERR_INVALID_ARGUMENT;
3042 			goto out;
3043 		}
3044 		if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 ||
3045 		    (r = sshbuf_put_u32(kdf, rounds)) != 0)
3046 			goto out;
3047 	} else if (strcmp(kdfname, "none") != 0) {
3048 		/* Unsupported KDF type */
3049 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3050 		goto out;
3051 	}
3052 	if ((r = cipher_init(&ciphercontext, cipher, key, keylen,
3053 	    key + keylen, ivlen, 1)) != 0)
3054 		goto out;
3055 
3056 	if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 ||
3057 	    (r = sshbuf_put_cstring(encoded, ciphername)) != 0 ||
3058 	    (r = sshbuf_put_cstring(encoded, kdfname)) != 0 ||
3059 	    (r = sshbuf_put_stringb(encoded, kdf)) != 0 ||
3060 	    (r = sshbuf_put_u32(encoded, 1)) != 0 ||	/* number of keys */
3061 	    (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 ||
3062 	    (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0)
3063 		goto out;
3064 
3065 	/* set up the buffer that will be encrypted */
3066 
3067 	/* Random check bytes */
3068 	check = arc4random();
3069 	if ((r = sshbuf_put_u32(encrypted, check)) != 0 ||
3070 	    (r = sshbuf_put_u32(encrypted, check)) != 0)
3071 		goto out;
3072 
3073 	/* append private key and comment*/
3074 	if ((r = sshkey_private_serialize(prv, encrypted)) != 0 ||
3075 	    (r = sshbuf_put_cstring(encrypted, comment)) != 0)
3076 		goto out;
3077 
3078 	/* padding */
3079 	i = 0;
3080 	while (sshbuf_len(encrypted) % blocksize) {
3081 		if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0)
3082 			goto out;
3083 	}
3084 
3085 	/* length in destination buffer */
3086 	if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0)
3087 		goto out;
3088 
3089 	/* encrypt */
3090 	if ((r = sshbuf_reserve(encoded,
3091 	    sshbuf_len(encrypted) + authlen, &cp)) != 0)
3092 		goto out;
3093 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3094 	    sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0)
3095 		goto out;
3096 
3097 	/* uuencode */
3098 	if ((b64 = sshbuf_dtob64(encoded)) == NULL) {
3099 		r = SSH_ERR_ALLOC_FAIL;
3100 		goto out;
3101 	}
3102 
3103 	sshbuf_reset(blob);
3104 	if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0)
3105 		goto out;
3106 	for (i = 0; i < strlen(b64); i++) {
3107 		if ((r = sshbuf_put_u8(blob, b64[i])) != 0)
3108 			goto out;
3109 		/* insert line breaks */
3110 		if (i % 70 == 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3111 			goto out;
3112 	}
3113 	if (i % 70 != 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3114 		goto out;
3115 	if ((r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0)
3116 		goto out;
3117 
3118 	/* success */
3119 	r = 0;
3120 
3121  out:
3122 	sshbuf_free(kdf);
3123 	sshbuf_free(encoded);
3124 	sshbuf_free(encrypted);
3125 	cipher_cleanup(&ciphercontext);
3126 	explicit_bzero(salt, sizeof(salt));
3127 	if (key != NULL) {
3128 		explicit_bzero(key, keylen + ivlen);
3129 		free(key);
3130 	}
3131 	if (pubkeyblob != NULL) {
3132 		explicit_bzero(pubkeyblob, pubkeylen);
3133 		free(pubkeyblob);
3134 	}
3135 	if (b64 != NULL) {
3136 		explicit_bzero(b64, strlen(b64));
3137 		free(b64);
3138 	}
3139 	return r;
3140 }
3141 
3142 static int
3143 sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase,
3144     struct sshkey **keyp, char **commentp)
3145 {
3146 	char *comment = NULL, *ciphername = NULL, *kdfname = NULL;
3147 	const struct sshcipher *cipher = NULL;
3148 	const u_char *cp;
3149 	int r = SSH_ERR_INTERNAL_ERROR;
3150 	size_t encoded_len;
3151 	size_t i, keylen = 0, ivlen = 0, authlen = 0, slen = 0;
3152 	struct sshbuf *encoded = NULL, *decoded = NULL;
3153 	struct sshbuf *kdf = NULL, *decrypted = NULL;
3154 	struct sshcipher_ctx ciphercontext;
3155 	struct sshkey *k = NULL;
3156 	u_char *key = NULL, *salt = NULL, *dp, pad, last;
3157 	u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
3158 
3159 	memset(&ciphercontext, 0, sizeof(ciphercontext));
3160 	if (keyp != NULL)
3161 		*keyp = NULL;
3162 	if (commentp != NULL)
3163 		*commentp = NULL;
3164 
3165 	if ((encoded = sshbuf_new()) == NULL ||
3166 	    (decoded = sshbuf_new()) == NULL ||
3167 	    (decrypted = sshbuf_new()) == NULL) {
3168 		r = SSH_ERR_ALLOC_FAIL;
3169 		goto out;
3170 	}
3171 
3172 	/* check preamble */
3173 	cp = sshbuf_ptr(blob);
3174 	encoded_len = sshbuf_len(blob);
3175 	if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) ||
3176 	    memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) {
3177 		r = SSH_ERR_INVALID_FORMAT;
3178 		goto out;
3179 	}
3180 	cp += MARK_BEGIN_LEN;
3181 	encoded_len -= MARK_BEGIN_LEN;
3182 
3183 	/* Look for end marker, removing whitespace as we go */
3184 	while (encoded_len > 0) {
3185 		if (*cp != '\n' && *cp != '\r') {
3186 			if ((r = sshbuf_put_u8(encoded, *cp)) != 0)
3187 				goto out;
3188 		}
3189 		last = *cp;
3190 		encoded_len--;
3191 		cp++;
3192 		if (last == '\n') {
3193 			if (encoded_len >= MARK_END_LEN &&
3194 			    memcmp(cp, MARK_END, MARK_END_LEN) == 0) {
3195 				/* \0 terminate */
3196 				if ((r = sshbuf_put_u8(encoded, 0)) != 0)
3197 					goto out;
3198 				break;
3199 			}
3200 		}
3201 	}
3202 	if (encoded_len == 0) {
3203 		r = SSH_ERR_INVALID_FORMAT;
3204 		goto out;
3205 	}
3206 
3207 	/* decode base64 */
3208 	if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0)
3209 		goto out;
3210 
3211 	/* check magic */
3212 	if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) ||
3213 	    memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) {
3214 		r = SSH_ERR_INVALID_FORMAT;
3215 		goto out;
3216 	}
3217 	/* parse public portion of key */
3218 	if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
3219 	    (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 ||
3220 	    (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 ||
3221 	    (r = sshbuf_froms(decoded, &kdf)) != 0 ||
3222 	    (r = sshbuf_get_u32(decoded, &nkeys)) != 0 ||
3223 	    (r = sshbuf_skip_string(decoded)) != 0 || /* pubkey */
3224 	    (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0)
3225 		goto out;
3226 
3227 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
3228 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3229 		goto out;
3230 	}
3231 	if ((passphrase == NULL || strlen(passphrase) == 0) &&
3232 	    strcmp(ciphername, "none") != 0) {
3233 		/* passphrase required */
3234 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3235 		goto out;
3236 	}
3237 	if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) {
3238 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3239 		goto out;
3240 	}
3241 	if (!strcmp(kdfname, "none") && strcmp(ciphername, "none") != 0) {
3242 		r = SSH_ERR_INVALID_FORMAT;
3243 		goto out;
3244 	}
3245 	if (nkeys != 1) {
3246 		/* XXX only one key supported */
3247 		r = SSH_ERR_INVALID_FORMAT;
3248 		goto out;
3249 	}
3250 
3251 	/* check size of encrypted key blob */
3252 	blocksize = cipher_blocksize(cipher);
3253 	if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) {
3254 		r = SSH_ERR_INVALID_FORMAT;
3255 		goto out;
3256 	}
3257 
3258 	/* setup key */
3259 	keylen = cipher_keylen(cipher);
3260 	ivlen = cipher_ivlen(cipher);
3261 	authlen = cipher_authlen(cipher);
3262 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
3263 		r = SSH_ERR_ALLOC_FAIL;
3264 		goto out;
3265 	}
3266 	if (strcmp(kdfname, "bcrypt") == 0) {
3267 		if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
3268 		    (r = sshbuf_get_u32(kdf, &rounds)) != 0)
3269 			goto out;
3270 		if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
3271 		    key, keylen + ivlen, rounds) < 0) {
3272 			r = SSH_ERR_INVALID_FORMAT;
3273 			goto out;
3274 		}
3275 	}
3276 
3277 	/* check that an appropriate amount of auth data is present */
3278 	if (sshbuf_len(decoded) < encrypted_len + authlen) {
3279 		r = SSH_ERR_INVALID_FORMAT;
3280 		goto out;
3281 	}
3282 
3283 	/* decrypt private portion of key */
3284 	if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 ||
3285 	    (r = cipher_init(&ciphercontext, cipher, key, keylen,
3286 	    key + keylen, ivlen, 0)) != 0)
3287 		goto out;
3288 	if ((r = cipher_crypt(&ciphercontext, 0, dp, sshbuf_ptr(decoded),
3289 	    encrypted_len, 0, authlen)) != 0) {
3290 		/* an integrity error here indicates an incorrect passphrase */
3291 		if (r == SSH_ERR_MAC_INVALID)
3292 			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3293 		goto out;
3294 	}
3295 	if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0)
3296 		goto out;
3297 	/* there should be no trailing data */
3298 	if (sshbuf_len(decoded) != 0) {
3299 		r = SSH_ERR_INVALID_FORMAT;
3300 		goto out;
3301 	}
3302 
3303 	/* check check bytes */
3304 	if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 ||
3305 	    (r = sshbuf_get_u32(decrypted, &check2)) != 0)
3306 		goto out;
3307 	if (check1 != check2) {
3308 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3309 		goto out;
3310 	}
3311 
3312 	/* Load the private key and comment */
3313 	if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 ||
3314 	    (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0)
3315 		goto out;
3316 
3317 	/* Check deterministic padding */
3318 	i = 0;
3319 	while (sshbuf_len(decrypted)) {
3320 		if ((r = sshbuf_get_u8(decrypted, &pad)) != 0)
3321 			goto out;
3322 		if (pad != (++i & 0xff)) {
3323 			r = SSH_ERR_INVALID_FORMAT;
3324 			goto out;
3325 		}
3326 	}
3327 
3328 	/* XXX decode pubkey and check against private */
3329 
3330 	/* success */
3331 	r = 0;
3332 	if (keyp != NULL) {
3333 		*keyp = k;
3334 		k = NULL;
3335 	}
3336 	if (commentp != NULL) {
3337 		*commentp = comment;
3338 		comment = NULL;
3339 	}
3340  out:
3341 	pad = 0;
3342 	cipher_cleanup(&ciphercontext);
3343 	free(ciphername);
3344 	free(kdfname);
3345 	free(comment);
3346 	if (salt != NULL) {
3347 		explicit_bzero(salt, slen);
3348 		free(salt);
3349 	}
3350 	if (key != NULL) {
3351 		explicit_bzero(key, keylen + ivlen);
3352 		free(key);
3353 	}
3354 	sshbuf_free(encoded);
3355 	sshbuf_free(decoded);
3356 	sshbuf_free(kdf);
3357 	sshbuf_free(decrypted);
3358 	sshkey_free(k);
3359 	return r;
3360 }
3361 
3362 #if WITH_SSH1
3363 /*
3364  * Serialises the authentication (private) key to a blob, encrypting it with
3365  * passphrase.  The identification of the blob (lowest 64 bits of n) will
3366  * precede the key to provide identification of the key without needing a
3367  * passphrase.
3368  */
3369 static int
3370 sshkey_private_rsa1_to_blob(struct sshkey *key, struct sshbuf *blob,
3371     const char *passphrase, const char *comment)
3372 {
3373 	struct sshbuf *buffer = NULL, *encrypted = NULL;
3374 	u_char buf[8];
3375 	int r, cipher_num;
3376 	struct sshcipher_ctx ciphercontext;
3377 	const struct sshcipher *cipher;
3378 	u_char *cp;
3379 
3380 	/*
3381 	 * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
3382 	 * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
3383 	 */
3384 	cipher_num = (strcmp(passphrase, "") == 0) ?
3385 	    SSH_CIPHER_NONE : SSH_CIPHER_3DES;
3386 	if ((cipher = cipher_by_number(cipher_num)) == NULL)
3387 		return SSH_ERR_INTERNAL_ERROR;
3388 
3389 	/* This buffer is used to build the secret part of the private key. */
3390 	if ((buffer = sshbuf_new()) == NULL)
3391 		return SSH_ERR_ALLOC_FAIL;
3392 
3393 	/* Put checkbytes for checking passphrase validity. */
3394 	if ((r = sshbuf_reserve(buffer, 4, &cp)) != 0)
3395 		goto out;
3396 	arc4random_buf(cp, 2);
3397 	memcpy(cp + 2, cp, 2);
3398 
3399 	/*
3400 	 * Store the private key (n and e will not be stored because they
3401 	 * will be stored in plain text, and storing them also in encrypted
3402 	 * format would just give known plaintext).
3403 	 * Note: q and p are stored in reverse order to SSL.
3404 	 */
3405 	if ((r = sshbuf_put_bignum1(buffer, key->rsa->d)) != 0 ||
3406 	    (r = sshbuf_put_bignum1(buffer, key->rsa->iqmp)) != 0 ||
3407 	    (r = sshbuf_put_bignum1(buffer, key->rsa->q)) != 0 ||
3408 	    (r = sshbuf_put_bignum1(buffer, key->rsa->p)) != 0)
3409 		goto out;
3410 
3411 	/* Pad the part to be encrypted to a size that is a multiple of 8. */
3412 	explicit_bzero(buf, 8);
3413 	if ((r = sshbuf_put(buffer, buf, 8 - (sshbuf_len(buffer) % 8))) != 0)
3414 		goto out;
3415 
3416 	/* This buffer will be used to contain the data in the file. */
3417 	if ((encrypted = sshbuf_new()) == NULL) {
3418 		r = SSH_ERR_ALLOC_FAIL;
3419 		goto out;
3420 	}
3421 
3422 	/* First store keyfile id string. */
3423 	if ((r = sshbuf_put(encrypted, LEGACY_BEGIN,
3424 	    sizeof(LEGACY_BEGIN))) != 0)
3425 		goto out;
3426 
3427 	/* Store cipher type and "reserved" field. */
3428 	if ((r = sshbuf_put_u8(encrypted, cipher_num)) != 0 ||
3429 	    (r = sshbuf_put_u32(encrypted, 0)) != 0)
3430 		goto out;
3431 
3432 	/* Store public key.  This will be in plain text. */
3433 	if ((r = sshbuf_put_u32(encrypted, BN_num_bits(key->rsa->n))) != 0 ||
3434 	    (r = sshbuf_put_bignum1(encrypted, key->rsa->n) != 0) ||
3435 	    (r = sshbuf_put_bignum1(encrypted, key->rsa->e) != 0) ||
3436 	    (r = sshbuf_put_cstring(encrypted, comment) != 0))
3437 		goto out;
3438 
3439 	/* Allocate space for the private part of the key in the buffer. */
3440 	if ((r = sshbuf_reserve(encrypted, sshbuf_len(buffer), &cp)) != 0)
3441 		goto out;
3442 
3443 	if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase,
3444 	    CIPHER_ENCRYPT)) != 0)
3445 		goto out;
3446 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3447 	    sshbuf_ptr(buffer), sshbuf_len(buffer), 0, 0)) != 0)
3448 		goto out;
3449 	if ((r = cipher_cleanup(&ciphercontext)) != 0)
3450 		goto out;
3451 
3452 	r = sshbuf_putb(blob, encrypted);
3453 
3454  out:
3455 	explicit_bzero(&ciphercontext, sizeof(ciphercontext));
3456 	explicit_bzero(buf, sizeof(buf));
3457 	if (buffer != NULL)
3458 		sshbuf_free(buffer);
3459 	if (encrypted != NULL)
3460 		sshbuf_free(encrypted);
3461 
3462 	return r;
3463 }
3464 #endif /* WITH_SSH1 */
3465 
3466 #ifdef WITH_OPENSSL
3467 /* convert SSH v2 key in OpenSSL PEM format */
3468 static int
3469 sshkey_private_pem_to_blob(struct sshkey *key, struct sshbuf *blob,
3470     const char *_passphrase, const char *comment)
3471 {
3472 	int success, r;
3473 	int blen, len = strlen(_passphrase);
3474 	u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
3475 #if (OPENSSL_VERSION_NUMBER < 0x00907000L)
3476 	const EVP_CIPHER *cipher = (len > 0) ? EVP_des_ede3_cbc() : NULL;
3477 #else
3478  	const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
3479 #endif
3480 	const u_char *bptr;
3481 	BIO *bio = NULL;
3482 
3483 	if (len > 0 && len <= 4)
3484 		return SSH_ERR_PASSPHRASE_TOO_SHORT;
3485 	if ((bio = BIO_new(BIO_s_mem())) == NULL)
3486 		return SSH_ERR_ALLOC_FAIL;
3487 
3488 	switch (key->type) {
3489 	case KEY_DSA:
3490 		success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
3491 		    cipher, passphrase, len, NULL, NULL);
3492 		break;
3493 #ifdef OPENSSL_HAS_ECC
3494 	case KEY_ECDSA:
3495 		success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
3496 		    cipher, passphrase, len, NULL, NULL);
3497 		break;
3498 #endif
3499 	case KEY_RSA:
3500 		success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
3501 		    cipher, passphrase, len, NULL, NULL);
3502 		break;
3503 	default:
3504 		success = 0;
3505 		break;
3506 	}
3507 	if (success == 0) {
3508 		r = SSH_ERR_LIBCRYPTO_ERROR;
3509 		goto out;
3510 	}
3511 	if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) {
3512 		r = SSH_ERR_INTERNAL_ERROR;
3513 		goto out;
3514 	}
3515 	if ((r = sshbuf_put(blob, bptr, blen)) != 0)
3516 		goto out;
3517 	r = 0;
3518  out:
3519 	BIO_free(bio);
3520 	return r;
3521 }
3522 #endif /* WITH_OPENSSL */
3523 
3524 /* Serialise "key" to buffer "blob" */
3525 int
3526 sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
3527     const char *passphrase, const char *comment,
3528     int force_new_format, const char *new_format_cipher, int new_format_rounds)
3529 {
3530 	switch (key->type) {
3531 #ifdef WITH_SSH1
3532 	case KEY_RSA1:
3533 		return sshkey_private_rsa1_to_blob(key, blob,
3534 		    passphrase, comment);
3535 #endif /* WITH_SSH1 */
3536 #ifdef WITH_OPENSSL
3537 	case KEY_DSA:
3538 	case KEY_ECDSA:
3539 	case KEY_RSA:
3540 		if (force_new_format) {
3541 			return sshkey_private_to_blob2(key, blob, passphrase,
3542 			    comment, new_format_cipher, new_format_rounds);
3543 		}
3544 		return sshkey_private_pem_to_blob(key, blob,
3545 		    passphrase, comment);
3546 #endif /* WITH_OPENSSL */
3547 	case KEY_ED25519:
3548 		return sshkey_private_to_blob2(key, blob, passphrase,
3549 		    comment, new_format_cipher, new_format_rounds);
3550 	default:
3551 		return SSH_ERR_KEY_TYPE_UNKNOWN;
3552 	}
3553 }
3554 
3555 #ifdef WITH_SSH1
3556 /*
3557  * Parse the public, unencrypted portion of a RSA1 key.
3558  */
3559 int
3560 sshkey_parse_public_rsa1_fileblob(struct sshbuf *blob,
3561     struct sshkey **keyp, char **commentp)
3562 {
3563 	int r;
3564 	struct sshkey *pub = NULL;
3565 	struct sshbuf *copy = NULL;
3566 
3567 	if (keyp != NULL)
3568 		*keyp = NULL;
3569 	if (commentp != NULL)
3570 		*commentp = NULL;
3571 
3572 	/* Check that it is at least big enough to contain the ID string. */
3573 	if (sshbuf_len(blob) < sizeof(LEGACY_BEGIN))
3574 		return SSH_ERR_INVALID_FORMAT;
3575 
3576 	/*
3577 	 * Make sure it begins with the id string.  Consume the id string
3578 	 * from the buffer.
3579 	 */
3580 	if (memcmp(sshbuf_ptr(blob), LEGACY_BEGIN, sizeof(LEGACY_BEGIN)) != 0)
3581 		return SSH_ERR_INVALID_FORMAT;
3582 	/* Make a working copy of the keyblob and skip past the magic */
3583 	if ((copy = sshbuf_fromb(blob)) == NULL)
3584 		return SSH_ERR_ALLOC_FAIL;
3585 	if ((r = sshbuf_consume(copy, sizeof(LEGACY_BEGIN))) != 0)
3586 		goto out;
3587 
3588 	/* Skip cipher type, reserved data and key bits. */
3589 	if ((r = sshbuf_get_u8(copy, NULL)) != 0 ||	/* cipher type */
3590 	    (r = sshbuf_get_u32(copy, NULL)) != 0 ||	/* reserved */
3591 	    (r = sshbuf_get_u32(copy, NULL)) != 0)	/* key bits */
3592 		goto out;
3593 
3594 	/* Read the public key from the buffer. */
3595 	if ((pub = sshkey_new(KEY_RSA1)) == NULL ||
3596 	    (r = sshbuf_get_bignum1(copy, pub->rsa->n)) != 0 ||
3597 	    (r = sshbuf_get_bignum1(copy, pub->rsa->e)) != 0)
3598 		goto out;
3599 
3600 	/* Finally, the comment */
3601 	if ((r = sshbuf_get_string(copy, (u_char**)commentp, NULL)) != 0)
3602 		goto out;
3603 
3604 	/* The encrypted private part is not parsed by this function. */
3605 
3606 	r = 0;
3607 	if (keyp != NULL)
3608 		*keyp = pub;
3609 	else
3610 		sshkey_free(pub);
3611 	pub = NULL;
3612 
3613  out:
3614 	if (copy != NULL)
3615 		sshbuf_free(copy);
3616 	if (pub != NULL)
3617 		sshkey_free(pub);
3618 	return r;
3619 }
3620 
3621 static int
3622 sshkey_parse_private_rsa1(struct sshbuf *blob, const char *passphrase,
3623     struct sshkey **keyp, char **commentp)
3624 {
3625 	int r;
3626 	u_int16_t check1, check2;
3627 	u_int8_t cipher_type;
3628 	struct sshbuf *decrypted = NULL, *copy = NULL;
3629 	u_char *cp;
3630 	char *comment = NULL;
3631 	struct sshcipher_ctx ciphercontext;
3632 	const struct sshcipher *cipher;
3633 	struct sshkey *prv = NULL;
3634 
3635 	*keyp = NULL;
3636 	if (commentp != NULL)
3637 		*commentp = NULL;
3638 
3639 	/* Check that it is at least big enough to contain the ID string. */
3640 	if (sshbuf_len(blob) < sizeof(LEGACY_BEGIN))
3641 		return SSH_ERR_INVALID_FORMAT;
3642 
3643 	/*
3644 	 * Make sure it begins with the id string.  Consume the id string
3645 	 * from the buffer.
3646 	 */
3647 	if (memcmp(sshbuf_ptr(blob), LEGACY_BEGIN, sizeof(LEGACY_BEGIN)) != 0)
3648 		return SSH_ERR_INVALID_FORMAT;
3649 
3650 	if ((prv = sshkey_new_private(KEY_RSA1)) == NULL) {
3651 		r = SSH_ERR_ALLOC_FAIL;
3652 		goto out;
3653 	}
3654 	if ((copy = sshbuf_fromb(blob)) == NULL ||
3655 	    (decrypted = sshbuf_new()) == NULL) {
3656 		r = SSH_ERR_ALLOC_FAIL;
3657 		goto out;
3658 	}
3659 	if ((r = sshbuf_consume(copy, sizeof(LEGACY_BEGIN))) != 0)
3660 		goto out;
3661 
3662 	/* Read cipher type. */
3663 	if ((r = sshbuf_get_u8(copy, &cipher_type)) != 0 ||
3664 	    (r = sshbuf_get_u32(copy, NULL)) != 0)	/* reserved */
3665 		goto out;
3666 
3667 	/* Read the public key and comment from the buffer. */
3668 	if ((r = sshbuf_get_u32(copy, NULL)) != 0 ||	/* key bits */
3669 	    (r = sshbuf_get_bignum1(copy, prv->rsa->n)) != 0 ||
3670 	    (r = sshbuf_get_bignum1(copy, prv->rsa->e)) != 0 ||
3671 	    (r = sshbuf_get_cstring(copy, &comment, NULL)) != 0)
3672 		goto out;
3673 
3674 	/* Check that it is a supported cipher. */
3675 	cipher = cipher_by_number(cipher_type);
3676 	if (cipher == NULL) {
3677 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3678 		goto out;
3679 	}
3680 	/* Initialize space for decrypted data. */
3681 	if ((r = sshbuf_reserve(decrypted, sshbuf_len(copy), &cp)) != 0)
3682 		goto out;
3683 
3684 	/* Rest of the buffer is encrypted.  Decrypt it using the passphrase. */
3685 	if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase,
3686 	    CIPHER_DECRYPT)) != 0)
3687 		goto out;
3688 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3689 	    sshbuf_ptr(copy), sshbuf_len(copy), 0, 0)) != 0) {
3690 		cipher_cleanup(&ciphercontext);
3691 		goto out;
3692 	}
3693 	if ((r = cipher_cleanup(&ciphercontext)) != 0)
3694 		goto out;
3695 
3696 	if ((r = sshbuf_get_u16(decrypted, &check1)) != 0 ||
3697 	    (r = sshbuf_get_u16(decrypted, &check2)) != 0)
3698 		goto out;
3699 	if (check1 != check2) {
3700 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3701 		goto out;
3702 	}
3703 
3704 	/* Read the rest of the private key. */
3705 	if ((r = sshbuf_get_bignum1(decrypted, prv->rsa->d)) != 0 ||
3706 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->iqmp)) != 0 ||
3707 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->q)) != 0 ||
3708 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->p)) != 0)
3709 		goto out;
3710 
3711 	/* calculate p-1 and q-1 */
3712 	if ((r = rsa_generate_additional_parameters(prv->rsa)) != 0)
3713 		goto out;
3714 
3715 	/* enable blinding */
3716 	if (RSA_blinding_on(prv->rsa, NULL) != 1) {
3717 		r = SSH_ERR_LIBCRYPTO_ERROR;
3718 		goto out;
3719 	}
3720 	r = 0;
3721 	*keyp = prv;
3722 	prv = NULL;
3723 	if (commentp != NULL) {
3724 		*commentp = comment;
3725 		comment = NULL;
3726 	}
3727  out:
3728 	explicit_bzero(&ciphercontext, sizeof(ciphercontext));
3729 	if (comment != NULL)
3730 		free(comment);
3731 	if (prv != NULL)
3732 		sshkey_free(prv);
3733 	if (copy != NULL)
3734 		sshbuf_free(copy);
3735 	if (decrypted != NULL)
3736 		sshbuf_free(decrypted);
3737 	return r;
3738 }
3739 #endif /* WITH_SSH1 */
3740 
3741 #ifdef WITH_OPENSSL
3742 static int
3743 sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
3744     const char *passphrase, struct sshkey **keyp)
3745 {
3746 	EVP_PKEY *pk = NULL;
3747 	struct sshkey *prv = NULL;
3748 	BIO *bio = NULL;
3749 	int r;
3750 
3751 	*keyp = NULL;
3752 
3753 	if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
3754 		return SSH_ERR_ALLOC_FAIL;
3755 	if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) !=
3756 	    (int)sshbuf_len(blob)) {
3757 		r = SSH_ERR_ALLOC_FAIL;
3758 		goto out;
3759 	}
3760 
3761 	if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL,
3762 	    (char *)passphrase)) == NULL) {
3763 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3764 		goto out;
3765 	}
3766 	if (pk->type == EVP_PKEY_RSA &&
3767 	    (type == KEY_UNSPEC || type == KEY_RSA)) {
3768 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3769 			r = SSH_ERR_ALLOC_FAIL;
3770 			goto out;
3771 		}
3772 		prv->rsa = EVP_PKEY_get1_RSA(pk);
3773 		prv->type = KEY_RSA;
3774 #ifdef DEBUG_PK
3775 		RSA_print_fp(stderr, prv->rsa, 8);
3776 #endif
3777 		if (RSA_blinding_on(prv->rsa, NULL) != 1) {
3778 			r = SSH_ERR_LIBCRYPTO_ERROR;
3779 			goto out;
3780 		}
3781 	} else if (pk->type == EVP_PKEY_DSA &&
3782 	    (type == KEY_UNSPEC || type == KEY_DSA)) {
3783 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3784 			r = SSH_ERR_ALLOC_FAIL;
3785 			goto out;
3786 		}
3787 		prv->dsa = EVP_PKEY_get1_DSA(pk);
3788 		prv->type = KEY_DSA;
3789 #ifdef DEBUG_PK
3790 		DSA_print_fp(stderr, prv->dsa, 8);
3791 #endif
3792 #ifdef OPENSSL_HAS_ECC
3793 	} else if (pk->type == EVP_PKEY_EC &&
3794 	    (type == KEY_UNSPEC || type == KEY_ECDSA)) {
3795 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3796 			r = SSH_ERR_ALLOC_FAIL;
3797 			goto out;
3798 		}
3799 		prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
3800 		prv->type = KEY_ECDSA;
3801 		prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa);
3802 		if (prv->ecdsa_nid == -1 ||
3803 		    sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
3804 		    sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
3805 		    EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
3806 		    sshkey_ec_validate_private(prv->ecdsa) != 0) {
3807 			r = SSH_ERR_INVALID_FORMAT;
3808 			goto out;
3809 		}
3810 # ifdef DEBUG_PK
3811 		if (prv != NULL && prv->ecdsa != NULL)
3812 			sshkey_dump_ec_key(prv->ecdsa);
3813 # endif
3814 #endif /* OPENSSL_HAS_ECC */
3815 	} else {
3816 		r = SSH_ERR_INVALID_FORMAT;
3817 		goto out;
3818 	}
3819 	r = 0;
3820 	*keyp = prv;
3821 	prv = NULL;
3822  out:
3823 	BIO_free(bio);
3824 	if (pk != NULL)
3825 		EVP_PKEY_free(pk);
3826 	if (prv != NULL)
3827 		sshkey_free(prv);
3828 	return r;
3829 }
3830 #endif /* WITH_OPENSSL */
3831 
3832 int
3833 sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
3834     const char *passphrase, struct sshkey **keyp, char **commentp)
3835 {
3836 	int r;
3837 
3838 	*keyp = NULL;
3839 	if (commentp != NULL)
3840 		*commentp = NULL;
3841 
3842 	switch (type) {
3843 #ifdef WITH_SSH1
3844 	case KEY_RSA1:
3845 		return sshkey_parse_private_rsa1(blob, passphrase,
3846 		    keyp, commentp);
3847 #endif /* WITH_SSH1 */
3848 #ifdef WITH_OPENSSL
3849 	case KEY_DSA:
3850 	case KEY_ECDSA:
3851 	case KEY_RSA:
3852 		return sshkey_parse_private_pem_fileblob(blob, type,
3853 		    passphrase, keyp);
3854 #endif /* WITH_OPENSSL */
3855 	case KEY_ED25519:
3856 		return sshkey_parse_private2(blob, type, passphrase,
3857 		    keyp, commentp);
3858 	case KEY_UNSPEC:
3859 		if ((r = sshkey_parse_private2(blob, type, passphrase, keyp,
3860 		    commentp)) == 0)
3861 			return 0;
3862 #ifdef WITH_OPENSSL
3863 		return sshkey_parse_private_pem_fileblob(blob, type,
3864 		    passphrase, keyp);
3865 #else
3866 		return SSH_ERR_INVALID_FORMAT;
3867 #endif /* WITH_OPENSSL */
3868 	default:
3869 		return SSH_ERR_KEY_TYPE_UNKNOWN;
3870 	}
3871 }
3872 
3873 int
3874 sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase,
3875     const char *filename, struct sshkey **keyp, char **commentp)
3876 {
3877 	int r;
3878 
3879 	if (keyp != NULL)
3880 		*keyp = NULL;
3881 	if (commentp != NULL)
3882 		*commentp = NULL;
3883 
3884 #ifdef WITH_SSH1
3885 	/* it's a SSH v1 key if the public key part is readable */
3886 	if ((r = sshkey_parse_public_rsa1_fileblob(buffer, NULL, NULL)) == 0) {
3887 		return sshkey_parse_private_fileblob_type(buffer, KEY_RSA1,
3888 		    passphrase, keyp, commentp);
3889 	}
3890 #endif /* WITH_SSH1 */
3891 	if ((r = sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
3892 	    passphrase, keyp, commentp)) == 0)
3893 		return 0;
3894 	return r;
3895 }
3896