xref: /openbsd-src/usr.bin/ssh/sshkey.c (revision 7350f337b9e3eb4461d99580e625c7ef148d107c)
1 /* $OpenBSD: sshkey.c,v 1.77 2019/06/23 12:21:46 djm Exp $ */
2 /*
3  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
4  * Copyright (c) 2008 Alexander von Gernler.  All rights reserved.
5  * Copyright (c) 2010,2011 Damien Miller.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/types.h>
29 #include <netinet/in.h>
30 
31 #ifdef WITH_OPENSSL
32 #include <openssl/evp.h>
33 #include <openssl/err.h>
34 #include <openssl/pem.h>
35 #endif
36 
37 #include "crypto_api.h"
38 
39 #include <errno.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <util.h>
43 #include <limits.h>
44 #include <resolv.h>
45 
46 #include "ssh2.h"
47 #include "ssherr.h"
48 #include "misc.h"
49 #include "sshbuf.h"
50 #include "cipher.h"
51 #include "digest.h"
52 #define SSHKEY_INTERNAL
53 #include "sshkey.h"
54 #include "match.h"
55 
56 #ifdef WITH_XMSS
57 #include "sshkey-xmss.h"
58 #include "xmss_fast.h"
59 #endif
60 
61 /* openssh private key file format */
62 #define MARK_BEGIN		"-----BEGIN OPENSSH PRIVATE KEY-----\n"
63 #define MARK_END		"-----END OPENSSH PRIVATE KEY-----\n"
64 #define MARK_BEGIN_LEN		(sizeof(MARK_BEGIN) - 1)
65 #define MARK_END_LEN		(sizeof(MARK_END) - 1)
66 #define KDFNAME			"bcrypt"
67 #define AUTH_MAGIC		"openssh-key-v1"
68 #define SALT_LEN		16
69 #define DEFAULT_CIPHERNAME	"aes256-ctr"
70 #define	DEFAULT_ROUNDS		16
71 
72 /* Version identification string for SSH v1 identity files. */
73 #define LEGACY_BEGIN		"SSH PRIVATE KEY FILE FORMAT 1.1\n"
74 
75 /*
76  * Constants relating to "shielding" support; protection of keys expected
77  * to remain in memory for long durations
78  */
79 #define SSHKEY_SHIELD_PREKEY_LEN	(16 * 1024)
80 #define SSHKEY_SHIELD_CIPHER		"aes256-ctr" /* XXX want AES-EME* */
81 #define SSHKEY_SHIELD_PREKEY_HASH	SSH_DIGEST_SHA512
82 
83 int	sshkey_private_serialize_opt(struct sshkey *key,
84     struct sshbuf *buf, enum sshkey_serialize_rep);
85 static int sshkey_from_blob_internal(struct sshbuf *buf,
86     struct sshkey **keyp, int allow_cert);
87 static int get_sigtype(const u_char *sig, size_t siglen, char **sigtypep);
88 
89 /* Supported key types */
90 struct keytype {
91 	const char *name;
92 	const char *shortname;
93 	const char *sigalg;
94 	int type;
95 	int nid;
96 	int cert;
97 	int sigonly;
98 };
99 static const struct keytype keytypes[] = {
100 	{ "ssh-ed25519", "ED25519", NULL, KEY_ED25519, 0, 0, 0 },
101 	{ "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT", NULL,
102 	    KEY_ED25519_CERT, 0, 1, 0 },
103 #ifdef WITH_XMSS
104 	{ "ssh-xmss@openssh.com", "XMSS", NULL, KEY_XMSS, 0, 0, 0 },
105 	{ "ssh-xmss-cert-v01@openssh.com", "XMSS-CERT", NULL,
106 	    KEY_XMSS_CERT, 0, 1, 0 },
107 #endif /* WITH_XMSS */
108 #ifdef WITH_OPENSSL
109 	{ "ssh-rsa", "RSA", NULL, KEY_RSA, 0, 0, 0 },
110 	{ "rsa-sha2-256", "RSA", NULL, KEY_RSA, 0, 0, 1 },
111 	{ "rsa-sha2-512", "RSA", NULL, KEY_RSA, 0, 0, 1 },
112 	{ "ssh-dss", "DSA", NULL, KEY_DSA, 0, 0, 0 },
113 	{ "ecdsa-sha2-nistp256", "ECDSA", NULL,
114 	    KEY_ECDSA, NID_X9_62_prime256v1, 0, 0 },
115 	{ "ecdsa-sha2-nistp384", "ECDSA", NULL,
116 	    KEY_ECDSA, NID_secp384r1, 0, 0 },
117 	{ "ecdsa-sha2-nistp521", "ECDSA", NULL,
118 	    KEY_ECDSA, NID_secp521r1, 0, 0 },
119 	{ "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", NULL,
120 	    KEY_RSA_CERT, 0, 1, 0 },
121 	{ "rsa-sha2-256-cert-v01@openssh.com", "RSA-CERT",
122 	    "rsa-sha2-256", KEY_RSA_CERT, 0, 1, 1 },
123 	{ "rsa-sha2-512-cert-v01@openssh.com", "RSA-CERT",
124 	    "rsa-sha2-512", KEY_RSA_CERT, 0, 1, 1 },
125 	{ "ssh-dss-cert-v01@openssh.com", "DSA-CERT", NULL,
126 	    KEY_DSA_CERT, 0, 1, 0 },
127 	{ "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT", NULL,
128 	    KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1, 0 },
129 	{ "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT", NULL,
130 	    KEY_ECDSA_CERT, NID_secp384r1, 1, 0 },
131 	{ "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT", NULL,
132 	   KEY_ECDSA_CERT, NID_secp521r1, 1, 0 },
133 #endif /* WITH_OPENSSL */
134 	{ NULL, NULL, NULL, -1, -1, 0, 0 }
135 };
136 
137 const char *
138 sshkey_type(const struct sshkey *k)
139 {
140 	const struct keytype *kt;
141 
142 	for (kt = keytypes; kt->type != -1; kt++) {
143 		if (kt->type == k->type)
144 			return kt->shortname;
145 	}
146 	return "unknown";
147 }
148 
149 static const char *
150 sshkey_ssh_name_from_type_nid(int type, int nid)
151 {
152 	const struct keytype *kt;
153 
154 	for (kt = keytypes; kt->type != -1; kt++) {
155 		if (kt->type == type && (kt->nid == 0 || kt->nid == nid))
156 			return kt->name;
157 	}
158 	return "ssh-unknown";
159 }
160 
161 int
162 sshkey_type_is_cert(int type)
163 {
164 	const struct keytype *kt;
165 
166 	for (kt = keytypes; kt->type != -1; kt++) {
167 		if (kt->type == type)
168 			return kt->cert;
169 	}
170 	return 0;
171 }
172 
173 const char *
174 sshkey_ssh_name(const struct sshkey *k)
175 {
176 	return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
177 }
178 
179 const char *
180 sshkey_ssh_name_plain(const struct sshkey *k)
181 {
182 	return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type),
183 	    k->ecdsa_nid);
184 }
185 
186 int
187 sshkey_type_from_name(const char *name)
188 {
189 	const struct keytype *kt;
190 
191 	for (kt = keytypes; kt->type != -1; kt++) {
192 		/* Only allow shortname matches for plain key types */
193 		if ((kt->name != NULL && strcmp(name, kt->name) == 0) ||
194 		    (!kt->cert && strcasecmp(kt->shortname, name) == 0))
195 			return kt->type;
196 	}
197 	return KEY_UNSPEC;
198 }
199 
200 int
201 sshkey_ecdsa_nid_from_name(const char *name)
202 {
203 	const struct keytype *kt;
204 
205 	for (kt = keytypes; kt->type != -1; kt++) {
206 		if (kt->type != KEY_ECDSA && kt->type != KEY_ECDSA_CERT)
207 			continue;
208 		if (kt->name != NULL && strcmp(name, kt->name) == 0)
209 			return kt->nid;
210 	}
211 	return -1;
212 }
213 
214 char *
215 sshkey_alg_list(int certs_only, int plain_only, int include_sigonly, char sep)
216 {
217 	char *tmp, *ret = NULL;
218 	size_t nlen, rlen = 0;
219 	const struct keytype *kt;
220 
221 	for (kt = keytypes; kt->type != -1; kt++) {
222 		if (kt->name == NULL)
223 			continue;
224 		if (!include_sigonly && kt->sigonly)
225 			continue;
226 		if ((certs_only && !kt->cert) || (plain_only && kt->cert))
227 			continue;
228 		if (ret != NULL)
229 			ret[rlen++] = sep;
230 		nlen = strlen(kt->name);
231 		if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
232 			free(ret);
233 			return NULL;
234 		}
235 		ret = tmp;
236 		memcpy(ret + rlen, kt->name, nlen + 1);
237 		rlen += nlen;
238 	}
239 	return ret;
240 }
241 
242 int
243 sshkey_names_valid2(const char *names, int allow_wildcard)
244 {
245 	char *s, *cp, *p;
246 	const struct keytype *kt;
247 	int type;
248 
249 	if (names == NULL || strcmp(names, "") == 0)
250 		return 0;
251 	if ((s = cp = strdup(names)) == NULL)
252 		return 0;
253 	for ((p = strsep(&cp, ",")); p && *p != '\0';
254 	    (p = strsep(&cp, ","))) {
255 		type = sshkey_type_from_name(p);
256 		if (type == KEY_UNSPEC) {
257 			if (allow_wildcard) {
258 				/*
259 				 * Try matching key types against the string.
260 				 * If any has a positive or negative match then
261 				 * the component is accepted.
262 				 */
263 				for (kt = keytypes; kt->type != -1; kt++) {
264 					if (match_pattern_list(kt->name,
265 					    p, 0) != 0)
266 						break;
267 				}
268 				if (kt->type != -1)
269 					continue;
270 			}
271 			free(s);
272 			return 0;
273 		}
274 	}
275 	free(s);
276 	return 1;
277 }
278 
279 u_int
280 sshkey_size(const struct sshkey *k)
281 {
282 #ifdef WITH_OPENSSL
283 	const BIGNUM *rsa_n, *dsa_p;
284 #endif /* WITH_OPENSSL */
285 
286 	switch (k->type) {
287 #ifdef WITH_OPENSSL
288 	case KEY_RSA:
289 	case KEY_RSA_CERT:
290 		if (k->rsa == NULL)
291 			return 0;
292 		RSA_get0_key(k->rsa, &rsa_n, NULL, NULL);
293 		return BN_num_bits(rsa_n);
294 	case KEY_DSA:
295 	case KEY_DSA_CERT:
296 		if (k->dsa == NULL)
297 			return 0;
298 		DSA_get0_pqg(k->dsa, &dsa_p, NULL, NULL);
299 		return BN_num_bits(dsa_p);
300 	case KEY_ECDSA:
301 	case KEY_ECDSA_CERT:
302 		return sshkey_curve_nid_to_bits(k->ecdsa_nid);
303 #endif /* WITH_OPENSSL */
304 	case KEY_ED25519:
305 	case KEY_ED25519_CERT:
306 	case KEY_XMSS:
307 	case KEY_XMSS_CERT:
308 		return 256;	/* XXX */
309 	}
310 	return 0;
311 }
312 
313 static int
314 sshkey_type_is_valid_ca(int type)
315 {
316 	switch (type) {
317 	case KEY_RSA:
318 	case KEY_DSA:
319 	case KEY_ECDSA:
320 	case KEY_ED25519:
321 	case KEY_XMSS:
322 		return 1;
323 	default:
324 		return 0;
325 	}
326 }
327 
328 int
329 sshkey_is_cert(const struct sshkey *k)
330 {
331 	if (k == NULL)
332 		return 0;
333 	return sshkey_type_is_cert(k->type);
334 }
335 
336 /* Return the cert-less equivalent to a certified key type */
337 int
338 sshkey_type_plain(int type)
339 {
340 	switch (type) {
341 	case KEY_RSA_CERT:
342 		return KEY_RSA;
343 	case KEY_DSA_CERT:
344 		return KEY_DSA;
345 	case KEY_ECDSA_CERT:
346 		return KEY_ECDSA;
347 	case KEY_ED25519_CERT:
348 		return KEY_ED25519;
349 	case KEY_XMSS_CERT:
350 		return KEY_XMSS;
351 	default:
352 		return type;
353 	}
354 }
355 
356 #ifdef WITH_OPENSSL
357 /* XXX: these are really begging for a table-driven approach */
358 int
359 sshkey_curve_name_to_nid(const char *name)
360 {
361 	if (strcmp(name, "nistp256") == 0)
362 		return NID_X9_62_prime256v1;
363 	else if (strcmp(name, "nistp384") == 0)
364 		return NID_secp384r1;
365 	else if (strcmp(name, "nistp521") == 0)
366 		return NID_secp521r1;
367 	else
368 		return -1;
369 }
370 
371 u_int
372 sshkey_curve_nid_to_bits(int nid)
373 {
374 	switch (nid) {
375 	case NID_X9_62_prime256v1:
376 		return 256;
377 	case NID_secp384r1:
378 		return 384;
379 	case NID_secp521r1:
380 		return 521;
381 	default:
382 		return 0;
383 	}
384 }
385 
386 int
387 sshkey_ecdsa_bits_to_nid(int bits)
388 {
389 	switch (bits) {
390 	case 256:
391 		return NID_X9_62_prime256v1;
392 	case 384:
393 		return NID_secp384r1;
394 	case 521:
395 		return NID_secp521r1;
396 	default:
397 		return -1;
398 	}
399 }
400 
401 const char *
402 sshkey_curve_nid_to_name(int nid)
403 {
404 	switch (nid) {
405 	case NID_X9_62_prime256v1:
406 		return "nistp256";
407 	case NID_secp384r1:
408 		return "nistp384";
409 	case NID_secp521r1:
410 		return "nistp521";
411 	default:
412 		return NULL;
413 	}
414 }
415 
416 int
417 sshkey_ec_nid_to_hash_alg(int nid)
418 {
419 	int kbits = sshkey_curve_nid_to_bits(nid);
420 
421 	if (kbits <= 0)
422 		return -1;
423 
424 	/* RFC5656 section 6.2.1 */
425 	if (kbits <= 256)
426 		return SSH_DIGEST_SHA256;
427 	else if (kbits <= 384)
428 		return SSH_DIGEST_SHA384;
429 	else
430 		return SSH_DIGEST_SHA512;
431 }
432 #endif /* WITH_OPENSSL */
433 
434 static void
435 cert_free(struct sshkey_cert *cert)
436 {
437 	u_int i;
438 
439 	if (cert == NULL)
440 		return;
441 	sshbuf_free(cert->certblob);
442 	sshbuf_free(cert->critical);
443 	sshbuf_free(cert->extensions);
444 	free(cert->key_id);
445 	for (i = 0; i < cert->nprincipals; i++)
446 		free(cert->principals[i]);
447 	free(cert->principals);
448 	sshkey_free(cert->signature_key);
449 	free(cert->signature_type);
450 	freezero(cert, sizeof(*cert));
451 }
452 
453 static struct sshkey_cert *
454 cert_new(void)
455 {
456 	struct sshkey_cert *cert;
457 
458 	if ((cert = calloc(1, sizeof(*cert))) == NULL)
459 		return NULL;
460 	if ((cert->certblob = sshbuf_new()) == NULL ||
461 	    (cert->critical = sshbuf_new()) == NULL ||
462 	    (cert->extensions = sshbuf_new()) == NULL) {
463 		cert_free(cert);
464 		return NULL;
465 	}
466 	cert->key_id = NULL;
467 	cert->principals = NULL;
468 	cert->signature_key = NULL;
469 	cert->signature_type = NULL;
470 	return cert;
471 }
472 
473 struct sshkey *
474 sshkey_new(int type)
475 {
476 	struct sshkey *k;
477 #ifdef WITH_OPENSSL
478 	RSA *rsa;
479 	DSA *dsa;
480 #endif /* WITH_OPENSSL */
481 
482 	if ((k = calloc(1, sizeof(*k))) == NULL)
483 		return NULL;
484 	k->type = type;
485 	k->ecdsa = NULL;
486 	k->ecdsa_nid = -1;
487 	k->dsa = NULL;
488 	k->rsa = NULL;
489 	k->cert = NULL;
490 	k->ed25519_sk = NULL;
491 	k->ed25519_pk = NULL;
492 	k->xmss_sk = NULL;
493 	k->xmss_pk = NULL;
494 	switch (k->type) {
495 #ifdef WITH_OPENSSL
496 	case KEY_RSA:
497 	case KEY_RSA_CERT:
498 		if ((rsa = RSA_new()) == NULL) {
499 			free(k);
500 			return NULL;
501 		}
502 		k->rsa = rsa;
503 		break;
504 	case KEY_DSA:
505 	case KEY_DSA_CERT:
506 		if ((dsa = DSA_new()) == NULL) {
507 			free(k);
508 			return NULL;
509 		}
510 		k->dsa = dsa;
511 		break;
512 	case KEY_ECDSA:
513 	case KEY_ECDSA_CERT:
514 		/* Cannot do anything until we know the group */
515 		break;
516 #endif /* WITH_OPENSSL */
517 	case KEY_ED25519:
518 	case KEY_ED25519_CERT:
519 	case KEY_XMSS:
520 	case KEY_XMSS_CERT:
521 		/* no need to prealloc */
522 		break;
523 	case KEY_UNSPEC:
524 		break;
525 	default:
526 		free(k);
527 		return NULL;
528 	}
529 
530 	if (sshkey_is_cert(k)) {
531 		if ((k->cert = cert_new()) == NULL) {
532 			sshkey_free(k);
533 			return NULL;
534 		}
535 	}
536 
537 	return k;
538 }
539 
540 void
541 sshkey_free(struct sshkey *k)
542 {
543 	if (k == NULL)
544 		return;
545 	switch (k->type) {
546 #ifdef WITH_OPENSSL
547 	case KEY_RSA:
548 	case KEY_RSA_CERT:
549 		RSA_free(k->rsa);
550 		k->rsa = NULL;
551 		break;
552 	case KEY_DSA:
553 	case KEY_DSA_CERT:
554 		DSA_free(k->dsa);
555 		k->dsa = NULL;
556 		break;
557 	case KEY_ECDSA:
558 	case KEY_ECDSA_CERT:
559 		EC_KEY_free(k->ecdsa);
560 		k->ecdsa = NULL;
561 		break;
562 #endif /* WITH_OPENSSL */
563 	case KEY_ED25519:
564 	case KEY_ED25519_CERT:
565 		freezero(k->ed25519_pk, ED25519_PK_SZ);
566 		k->ed25519_pk = NULL;
567 		freezero(k->ed25519_sk, ED25519_SK_SZ);
568 		k->ed25519_sk = NULL;
569 		break;
570 #ifdef WITH_XMSS
571 	case KEY_XMSS:
572 	case KEY_XMSS_CERT:
573 		freezero(k->xmss_pk, sshkey_xmss_pklen(k));
574 		k->xmss_pk = NULL;
575 		freezero(k->xmss_sk, sshkey_xmss_sklen(k));
576 		k->xmss_sk = NULL;
577 		sshkey_xmss_free_state(k);
578 		free(k->xmss_name);
579 		k->xmss_name = NULL;
580 		free(k->xmss_filename);
581 		k->xmss_filename = NULL;
582 		break;
583 #endif /* WITH_XMSS */
584 	case KEY_UNSPEC:
585 		break;
586 	default:
587 		break;
588 	}
589 	if (sshkey_is_cert(k))
590 		cert_free(k->cert);
591 	freezero(k->shielded_private, k->shielded_len);
592 	freezero(k->shield_prekey, k->shield_prekey_len);
593 	freezero(k, sizeof(*k));
594 }
595 
596 static int
597 cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
598 {
599 	if (a == NULL && b == NULL)
600 		return 1;
601 	if (a == NULL || b == NULL)
602 		return 0;
603 	if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob))
604 		return 0;
605 	if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob),
606 	    sshbuf_len(a->certblob)) != 0)
607 		return 0;
608 	return 1;
609 }
610 
611 /*
612  * Compare public portions of key only, allowing comparisons between
613  * certificates and plain keys too.
614  */
615 int
616 sshkey_equal_public(const struct sshkey *a, const struct sshkey *b)
617 {
618 #ifdef WITH_OPENSSL
619 	BN_CTX *bnctx;
620 	const BIGNUM *rsa_e_a, *rsa_n_a;
621 	const BIGNUM *rsa_e_b, *rsa_n_b;
622 	const BIGNUM *dsa_p_a, *dsa_q_a, *dsa_g_a, *dsa_pub_key_a;
623 	const BIGNUM *dsa_p_b, *dsa_q_b, *dsa_g_b, *dsa_pub_key_b;
624 #endif /* WITH_OPENSSL */
625 
626 	if (a == NULL || b == NULL ||
627 	    sshkey_type_plain(a->type) != sshkey_type_plain(b->type))
628 		return 0;
629 
630 	switch (a->type) {
631 #ifdef WITH_OPENSSL
632 	case KEY_RSA_CERT:
633 	case KEY_RSA:
634 		if (a->rsa == NULL || b->rsa == NULL)
635 			return 0;
636 		RSA_get0_key(a->rsa, &rsa_n_a, &rsa_e_a, NULL);
637 		RSA_get0_key(b->rsa, &rsa_n_b, &rsa_e_b, NULL);
638 		return BN_cmp(rsa_e_a, rsa_e_b) == 0 &&
639 		    BN_cmp(rsa_n_a, rsa_n_b) == 0;
640 	case KEY_DSA_CERT:
641 	case KEY_DSA:
642 		if (a->dsa == NULL || b->dsa == NULL)
643 			return 0;
644 		DSA_get0_pqg(a->dsa, &dsa_p_a, &dsa_q_a, &dsa_g_a);
645 		DSA_get0_pqg(b->dsa, &dsa_p_b, &dsa_q_b, &dsa_g_b);
646 		DSA_get0_key(a->dsa, &dsa_pub_key_a, NULL);
647 		DSA_get0_key(b->dsa, &dsa_pub_key_b, NULL);
648 		return BN_cmp(dsa_p_a, dsa_p_b) == 0 &&
649 		    BN_cmp(dsa_q_a, dsa_q_b) == 0 &&
650 		    BN_cmp(dsa_g_a, dsa_g_b) == 0 &&
651 		    BN_cmp(dsa_pub_key_a, dsa_pub_key_b) == 0;
652 	case KEY_ECDSA_CERT:
653 	case KEY_ECDSA:
654 		if (a->ecdsa == NULL || b->ecdsa == NULL ||
655 		    EC_KEY_get0_public_key(a->ecdsa) == NULL ||
656 		    EC_KEY_get0_public_key(b->ecdsa) == NULL)
657 			return 0;
658 		if ((bnctx = BN_CTX_new()) == NULL)
659 			return 0;
660 		if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
661 		    EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
662 		    EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
663 		    EC_KEY_get0_public_key(a->ecdsa),
664 		    EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
665 			BN_CTX_free(bnctx);
666 			return 0;
667 		}
668 		BN_CTX_free(bnctx);
669 		return 1;
670 #endif /* WITH_OPENSSL */
671 	case KEY_ED25519:
672 	case KEY_ED25519_CERT:
673 		return a->ed25519_pk != NULL && b->ed25519_pk != NULL &&
674 		    memcmp(a->ed25519_pk, b->ed25519_pk, ED25519_PK_SZ) == 0;
675 #ifdef WITH_XMSS
676 	case KEY_XMSS:
677 	case KEY_XMSS_CERT:
678 		return a->xmss_pk != NULL && b->xmss_pk != NULL &&
679 		    sshkey_xmss_pklen(a) == sshkey_xmss_pklen(b) &&
680 		    memcmp(a->xmss_pk, b->xmss_pk, sshkey_xmss_pklen(a)) == 0;
681 #endif /* WITH_XMSS */
682 	default:
683 		return 0;
684 	}
685 	/* NOTREACHED */
686 }
687 
688 int
689 sshkey_equal(const struct sshkey *a, const struct sshkey *b)
690 {
691 	if (a == NULL || b == NULL || a->type != b->type)
692 		return 0;
693 	if (sshkey_is_cert(a)) {
694 		if (!cert_compare(a->cert, b->cert))
695 			return 0;
696 	}
697 	return sshkey_equal_public(a, b);
698 }
699 
700 static int
701 to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain,
702   enum sshkey_serialize_rep opts)
703 {
704 	int type, ret = SSH_ERR_INTERNAL_ERROR;
705 	const char *typename;
706 #ifdef WITH_OPENSSL
707 	const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
708 #endif /* WITH_OPENSSL */
709 
710 	if (key == NULL)
711 		return SSH_ERR_INVALID_ARGUMENT;
712 
713 	if (sshkey_is_cert(key)) {
714 		if (key->cert == NULL)
715 			return SSH_ERR_EXPECTED_CERT;
716 		if (sshbuf_len(key->cert->certblob) == 0)
717 			return SSH_ERR_KEY_LACKS_CERTBLOB;
718 	}
719 	type = force_plain ? sshkey_type_plain(key->type) : key->type;
720 	typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid);
721 
722 	switch (type) {
723 #ifdef WITH_OPENSSL
724 	case KEY_DSA_CERT:
725 	case KEY_ECDSA_CERT:
726 	case KEY_RSA_CERT:
727 #endif /* WITH_OPENSSL */
728 	case KEY_ED25519_CERT:
729 #ifdef WITH_XMSS
730 	case KEY_XMSS_CERT:
731 #endif /* WITH_XMSS */
732 		/* Use the existing blob */
733 		/* XXX modified flag? */
734 		if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0)
735 			return ret;
736 		break;
737 #ifdef WITH_OPENSSL
738 	case KEY_DSA:
739 		if (key->dsa == NULL)
740 			return SSH_ERR_INVALID_ARGUMENT;
741 		DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g);
742 		DSA_get0_key(key->dsa, &dsa_pub_key, NULL);
743 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
744 		    (ret = sshbuf_put_bignum2(b, dsa_p)) != 0 ||
745 		    (ret = sshbuf_put_bignum2(b, dsa_q)) != 0 ||
746 		    (ret = sshbuf_put_bignum2(b, dsa_g)) != 0 ||
747 		    (ret = sshbuf_put_bignum2(b, dsa_pub_key)) != 0)
748 			return ret;
749 		break;
750 	case KEY_ECDSA:
751 		if (key->ecdsa == NULL)
752 			return SSH_ERR_INVALID_ARGUMENT;
753 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
754 		    (ret = sshbuf_put_cstring(b,
755 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
756 		    (ret = sshbuf_put_eckey(b, key->ecdsa)) != 0)
757 			return ret;
758 		break;
759 	case KEY_RSA:
760 		if (key->rsa == NULL)
761 			return SSH_ERR_INVALID_ARGUMENT;
762 		RSA_get0_key(key->rsa, &rsa_n, &rsa_e, NULL);
763 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
764 		    (ret = sshbuf_put_bignum2(b, rsa_e)) != 0 ||
765 		    (ret = sshbuf_put_bignum2(b, rsa_n)) != 0)
766 			return ret;
767 		break;
768 #endif /* WITH_OPENSSL */
769 	case KEY_ED25519:
770 		if (key->ed25519_pk == NULL)
771 			return SSH_ERR_INVALID_ARGUMENT;
772 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
773 		    (ret = sshbuf_put_string(b,
774 		    key->ed25519_pk, ED25519_PK_SZ)) != 0)
775 			return ret;
776 		break;
777 #ifdef WITH_XMSS
778 	case KEY_XMSS:
779 		if (key->xmss_name == NULL || key->xmss_pk == NULL ||
780 		    sshkey_xmss_pklen(key) == 0)
781 			return SSH_ERR_INVALID_ARGUMENT;
782 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
783 		    (ret = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
784 		    (ret = sshbuf_put_string(b,
785 		    key->xmss_pk, sshkey_xmss_pklen(key))) != 0 ||
786 		    (ret = sshkey_xmss_serialize_pk_info(key, b, opts)) != 0)
787 			return ret;
788 		break;
789 #endif /* WITH_XMSS */
790 	default:
791 		return SSH_ERR_KEY_TYPE_UNKNOWN;
792 	}
793 	return 0;
794 }
795 
796 int
797 sshkey_putb(const struct sshkey *key, struct sshbuf *b)
798 {
799 	return to_blob_buf(key, b, 0, SSHKEY_SERIALIZE_DEFAULT);
800 }
801 
802 int
803 sshkey_puts_opts(const struct sshkey *key, struct sshbuf *b,
804     enum sshkey_serialize_rep opts)
805 {
806 	struct sshbuf *tmp;
807 	int r;
808 
809 	if ((tmp = sshbuf_new()) == NULL)
810 		return SSH_ERR_ALLOC_FAIL;
811 	r = to_blob_buf(key, tmp, 0, opts);
812 	if (r == 0)
813 		r = sshbuf_put_stringb(b, tmp);
814 	sshbuf_free(tmp);
815 	return r;
816 }
817 
818 int
819 sshkey_puts(const struct sshkey *key, struct sshbuf *b)
820 {
821 	return sshkey_puts_opts(key, b, SSHKEY_SERIALIZE_DEFAULT);
822 }
823 
824 int
825 sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b)
826 {
827 	return to_blob_buf(key, b, 1, SSHKEY_SERIALIZE_DEFAULT);
828 }
829 
830 static int
831 to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain,
832     enum sshkey_serialize_rep opts)
833 {
834 	int ret = SSH_ERR_INTERNAL_ERROR;
835 	size_t len;
836 	struct sshbuf *b = NULL;
837 
838 	if (lenp != NULL)
839 		*lenp = 0;
840 	if (blobp != NULL)
841 		*blobp = NULL;
842 	if ((b = sshbuf_new()) == NULL)
843 		return SSH_ERR_ALLOC_FAIL;
844 	if ((ret = to_blob_buf(key, b, force_plain, opts)) != 0)
845 		goto out;
846 	len = sshbuf_len(b);
847 	if (lenp != NULL)
848 		*lenp = len;
849 	if (blobp != NULL) {
850 		if ((*blobp = malloc(len)) == NULL) {
851 			ret = SSH_ERR_ALLOC_FAIL;
852 			goto out;
853 		}
854 		memcpy(*blobp, sshbuf_ptr(b), len);
855 	}
856 	ret = 0;
857  out:
858 	sshbuf_free(b);
859 	return ret;
860 }
861 
862 int
863 sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
864 {
865 	return to_blob(key, blobp, lenp, 0, SSHKEY_SERIALIZE_DEFAULT);
866 }
867 
868 int
869 sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
870 {
871 	return to_blob(key, blobp, lenp, 1, SSHKEY_SERIALIZE_DEFAULT);
872 }
873 
874 int
875 sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg,
876     u_char **retp, size_t *lenp)
877 {
878 	u_char *blob = NULL, *ret = NULL;
879 	size_t blob_len = 0;
880 	int r = SSH_ERR_INTERNAL_ERROR;
881 
882 	if (retp != NULL)
883 		*retp = NULL;
884 	if (lenp != NULL)
885 		*lenp = 0;
886 	if (ssh_digest_bytes(dgst_alg) == 0) {
887 		r = SSH_ERR_INVALID_ARGUMENT;
888 		goto out;
889 	}
890 	if ((r = to_blob(k, &blob, &blob_len, 1, SSHKEY_SERIALIZE_DEFAULT))
891 	    != 0)
892 		goto out;
893 	if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) {
894 		r = SSH_ERR_ALLOC_FAIL;
895 		goto out;
896 	}
897 	if ((r = ssh_digest_memory(dgst_alg, blob, blob_len,
898 	    ret, SSH_DIGEST_MAX_LENGTH)) != 0)
899 		goto out;
900 	/* success */
901 	if (retp != NULL) {
902 		*retp = ret;
903 		ret = NULL;
904 	}
905 	if (lenp != NULL)
906 		*lenp = ssh_digest_bytes(dgst_alg);
907 	r = 0;
908  out:
909 	free(ret);
910 	if (blob != NULL) {
911 		explicit_bzero(blob, blob_len);
912 		free(blob);
913 	}
914 	return r;
915 }
916 
917 static char *
918 fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
919 {
920 	char *ret;
921 	size_t plen = strlen(alg) + 1;
922 	size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1;
923 	int r;
924 
925 	if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL)
926 		return NULL;
927 	strlcpy(ret, alg, rlen);
928 	strlcat(ret, ":", rlen);
929 	if (dgst_raw_len == 0)
930 		return ret;
931 	if ((r = b64_ntop(dgst_raw, dgst_raw_len,
932 	    ret + plen, rlen - plen)) == -1) {
933 		freezero(ret, rlen);
934 		return NULL;
935 	}
936 	/* Trim padding characters from end */
937 	ret[strcspn(ret, "=")] = '\0';
938 	return ret;
939 }
940 
941 static char *
942 fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
943 {
944 	char *retval, hex[5];
945 	size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2;
946 
947 	if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL)
948 		return NULL;
949 	strlcpy(retval, alg, rlen);
950 	strlcat(retval, ":", rlen);
951 	for (i = 0; i < dgst_raw_len; i++) {
952 		snprintf(hex, sizeof(hex), "%s%02x",
953 		    i > 0 ? ":" : "", dgst_raw[i]);
954 		strlcat(retval, hex, rlen);
955 	}
956 	return retval;
957 }
958 
959 static char *
960 fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len)
961 {
962 	char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
963 	char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
964 	    'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
965 	u_int i, j = 0, rounds, seed = 1;
966 	char *retval;
967 
968 	rounds = (dgst_raw_len / 2) + 1;
969 	if ((retval = calloc(rounds, 6)) == NULL)
970 		return NULL;
971 	retval[j++] = 'x';
972 	for (i = 0; i < rounds; i++) {
973 		u_int idx0, idx1, idx2, idx3, idx4;
974 		if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
975 			idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
976 			    seed) % 6;
977 			idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
978 			idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
979 			    (seed / 6)) % 6;
980 			retval[j++] = vowels[idx0];
981 			retval[j++] = consonants[idx1];
982 			retval[j++] = vowels[idx2];
983 			if ((i + 1) < rounds) {
984 				idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
985 				idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
986 				retval[j++] = consonants[idx3];
987 				retval[j++] = '-';
988 				retval[j++] = consonants[idx4];
989 				seed = ((seed * 5) +
990 				    ((((u_int)(dgst_raw[2 * i])) * 7) +
991 				    ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
992 			}
993 		} else {
994 			idx0 = seed % 6;
995 			idx1 = 16;
996 			idx2 = seed / 6;
997 			retval[j++] = vowels[idx0];
998 			retval[j++] = consonants[idx1];
999 			retval[j++] = vowels[idx2];
1000 		}
1001 	}
1002 	retval[j++] = 'x';
1003 	retval[j++] = '\0';
1004 	return retval;
1005 }
1006 
1007 /*
1008  * Draw an ASCII-Art representing the fingerprint so human brain can
1009  * profit from its built-in pattern recognition ability.
1010  * This technique is called "random art" and can be found in some
1011  * scientific publications like this original paper:
1012  *
1013  * "Hash Visualization: a New Technique to improve Real-World Security",
1014  * Perrig A. and Song D., 1999, International Workshop on Cryptographic
1015  * Techniques and E-Commerce (CrypTEC '99)
1016  * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
1017  *
1018  * The subject came up in a talk by Dan Kaminsky, too.
1019  *
1020  * If you see the picture is different, the key is different.
1021  * If the picture looks the same, you still know nothing.
1022  *
1023  * The algorithm used here is a worm crawling over a discrete plane,
1024  * leaving a trace (augmenting the field) everywhere it goes.
1025  * Movement is taken from dgst_raw 2bit-wise.  Bumping into walls
1026  * makes the respective movement vector be ignored for this turn.
1027  * Graphs are not unambiguous, because circles in graphs can be
1028  * walked in either direction.
1029  */
1030 
1031 /*
1032  * Field sizes for the random art.  Have to be odd, so the starting point
1033  * can be in the exact middle of the picture, and FLDBASE should be >=8 .
1034  * Else pictures would be too dense, and drawing the frame would
1035  * fail, too, because the key type would not fit in anymore.
1036  */
1037 #define	FLDBASE		8
1038 #define	FLDSIZE_Y	(FLDBASE + 1)
1039 #define	FLDSIZE_X	(FLDBASE * 2 + 1)
1040 static char *
1041 fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
1042     const struct sshkey *k)
1043 {
1044 	/*
1045 	 * Chars to be used after each other every time the worm
1046 	 * intersects with itself.  Matter of taste.
1047 	 */
1048 	char	*augmentation_string = " .o+=*BOX@%&#/^SE";
1049 	char	*retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
1050 	u_char	 field[FLDSIZE_X][FLDSIZE_Y];
1051 	size_t	 i, tlen, hlen;
1052 	u_int	 b;
1053 	int	 x, y, r;
1054 	size_t	 len = strlen(augmentation_string) - 1;
1055 
1056 	if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
1057 		return NULL;
1058 
1059 	/* initialize field */
1060 	memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1061 	x = FLDSIZE_X / 2;
1062 	y = FLDSIZE_Y / 2;
1063 
1064 	/* process raw key */
1065 	for (i = 0; i < dgst_raw_len; i++) {
1066 		int input;
1067 		/* each byte conveys four 2-bit move commands */
1068 		input = dgst_raw[i];
1069 		for (b = 0; b < 4; b++) {
1070 			/* evaluate 2 bit, rest is shifted later */
1071 			x += (input & 0x1) ? 1 : -1;
1072 			y += (input & 0x2) ? 1 : -1;
1073 
1074 			/* assure we are still in bounds */
1075 			x = MAXIMUM(x, 0);
1076 			y = MAXIMUM(y, 0);
1077 			x = MINIMUM(x, FLDSIZE_X - 1);
1078 			y = MINIMUM(y, FLDSIZE_Y - 1);
1079 
1080 			/* augment the field */
1081 			if (field[x][y] < len - 2)
1082 				field[x][y]++;
1083 			input = input >> 2;
1084 		}
1085 	}
1086 
1087 	/* mark starting point and end point*/
1088 	field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
1089 	field[x][y] = len;
1090 
1091 	/* assemble title */
1092 	r = snprintf(title, sizeof(title), "[%s %u]",
1093 		sshkey_type(k), sshkey_size(k));
1094 	/* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */
1095 	if (r < 0 || r > (int)sizeof(title))
1096 		r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k));
1097 	tlen = (r <= 0) ? 0 : strlen(title);
1098 
1099 	/* assemble hash ID. */
1100 	r = snprintf(hash, sizeof(hash), "[%s]", alg);
1101 	hlen = (r <= 0) ? 0 : strlen(hash);
1102 
1103 	/* output upper border */
1104 	p = retval;
1105 	*p++ = '+';
1106 	for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
1107 		*p++ = '-';
1108 	memcpy(p, title, tlen);
1109 	p += tlen;
1110 	for (i += tlen; i < FLDSIZE_X; i++)
1111 		*p++ = '-';
1112 	*p++ = '+';
1113 	*p++ = '\n';
1114 
1115 	/* output content */
1116 	for (y = 0; y < FLDSIZE_Y; y++) {
1117 		*p++ = '|';
1118 		for (x = 0; x < FLDSIZE_X; x++)
1119 			*p++ = augmentation_string[MINIMUM(field[x][y], len)];
1120 		*p++ = '|';
1121 		*p++ = '\n';
1122 	}
1123 
1124 	/* output lower border */
1125 	*p++ = '+';
1126 	for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
1127 		*p++ = '-';
1128 	memcpy(p, hash, hlen);
1129 	p += hlen;
1130 	for (i += hlen; i < FLDSIZE_X; i++)
1131 		*p++ = '-';
1132 	*p++ = '+';
1133 
1134 	return retval;
1135 }
1136 
1137 char *
1138 sshkey_fingerprint(const struct sshkey *k, int dgst_alg,
1139     enum sshkey_fp_rep dgst_rep)
1140 {
1141 	char *retval = NULL;
1142 	u_char *dgst_raw;
1143 	size_t dgst_raw_len;
1144 
1145 	if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0)
1146 		return NULL;
1147 	switch (dgst_rep) {
1148 	case SSH_FP_DEFAULT:
1149 		if (dgst_alg == SSH_DIGEST_MD5) {
1150 			retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1151 			    dgst_raw, dgst_raw_len);
1152 		} else {
1153 			retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1154 			    dgst_raw, dgst_raw_len);
1155 		}
1156 		break;
1157 	case SSH_FP_HEX:
1158 		retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1159 		    dgst_raw, dgst_raw_len);
1160 		break;
1161 	case SSH_FP_BASE64:
1162 		retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1163 		    dgst_raw, dgst_raw_len);
1164 		break;
1165 	case SSH_FP_BUBBLEBABBLE:
1166 		retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1167 		break;
1168 	case SSH_FP_RANDOMART:
1169 		retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg),
1170 		    dgst_raw, dgst_raw_len, k);
1171 		break;
1172 	default:
1173 		explicit_bzero(dgst_raw, dgst_raw_len);
1174 		free(dgst_raw);
1175 		return NULL;
1176 	}
1177 	explicit_bzero(dgst_raw, dgst_raw_len);
1178 	free(dgst_raw);
1179 	return retval;
1180 }
1181 
1182 static int
1183 peek_type_nid(const char *s, size_t l, int *nid)
1184 {
1185 	const struct keytype *kt;
1186 
1187 	for (kt = keytypes; kt->type != -1; kt++) {
1188 		if (kt->name == NULL || strlen(kt->name) != l)
1189 			continue;
1190 		if (memcmp(s, kt->name, l) == 0) {
1191 			*nid = -1;
1192 			if (kt->type == KEY_ECDSA || kt->type == KEY_ECDSA_CERT)
1193 				*nid = kt->nid;
1194 			return kt->type;
1195 		}
1196 	}
1197 	return KEY_UNSPEC;
1198 }
1199 
1200 
1201 /* XXX this can now be made const char * */
1202 int
1203 sshkey_read(struct sshkey *ret, char **cpp)
1204 {
1205 	struct sshkey *k;
1206 	char *cp, *blobcopy;
1207 	size_t space;
1208 	int r, type, curve_nid = -1;
1209 	struct sshbuf *blob;
1210 
1211 	if (ret == NULL)
1212 		return SSH_ERR_INVALID_ARGUMENT;
1213 
1214 	switch (ret->type) {
1215 	case KEY_UNSPEC:
1216 	case KEY_RSA:
1217 	case KEY_DSA:
1218 	case KEY_ECDSA:
1219 	case KEY_ED25519:
1220 	case KEY_DSA_CERT:
1221 	case KEY_ECDSA_CERT:
1222 	case KEY_RSA_CERT:
1223 	case KEY_ED25519_CERT:
1224 #ifdef WITH_XMSS
1225 	case KEY_XMSS:
1226 	case KEY_XMSS_CERT:
1227 #endif /* WITH_XMSS */
1228 		break; /* ok */
1229 	default:
1230 		return SSH_ERR_INVALID_ARGUMENT;
1231 	}
1232 
1233 	/* Decode type */
1234 	cp = *cpp;
1235 	space = strcspn(cp, " \t");
1236 	if (space == strlen(cp))
1237 		return SSH_ERR_INVALID_FORMAT;
1238 	if ((type = peek_type_nid(cp, space, &curve_nid)) == KEY_UNSPEC)
1239 		return SSH_ERR_INVALID_FORMAT;
1240 
1241 	/* skip whitespace */
1242 	for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
1243 		;
1244 	if (*cp == '\0')
1245 		return SSH_ERR_INVALID_FORMAT;
1246 	if (ret->type != KEY_UNSPEC && ret->type != type)
1247 		return SSH_ERR_KEY_TYPE_MISMATCH;
1248 	if ((blob = sshbuf_new()) == NULL)
1249 		return SSH_ERR_ALLOC_FAIL;
1250 
1251 	/* find end of keyblob and decode */
1252 	space = strcspn(cp, " \t");
1253 	if ((blobcopy = strndup(cp, space)) == NULL) {
1254 		sshbuf_free(blob);
1255 		return SSH_ERR_ALLOC_FAIL;
1256 	}
1257 	if ((r = sshbuf_b64tod(blob, blobcopy)) != 0) {
1258 		free(blobcopy);
1259 		sshbuf_free(blob);
1260 		return r;
1261 	}
1262 	free(blobcopy);
1263 	if ((r = sshkey_fromb(blob, &k)) != 0) {
1264 		sshbuf_free(blob);
1265 		return r;
1266 	}
1267 	sshbuf_free(blob);
1268 
1269 	/* skip whitespace and leave cp at start of comment */
1270 	for (cp += space; *cp == ' ' || *cp == '\t'; cp++)
1271 		;
1272 
1273 	/* ensure type of blob matches type at start of line */
1274 	if (k->type != type) {
1275 		sshkey_free(k);
1276 		return SSH_ERR_KEY_TYPE_MISMATCH;
1277 	}
1278 	if (sshkey_type_plain(type) == KEY_ECDSA && curve_nid != k->ecdsa_nid) {
1279 		sshkey_free(k);
1280 		return SSH_ERR_EC_CURVE_MISMATCH;
1281 	}
1282 
1283 	/* Fill in ret from parsed key */
1284 	ret->type = type;
1285 	if (sshkey_is_cert(ret)) {
1286 		if (!sshkey_is_cert(k)) {
1287 			sshkey_free(k);
1288 			return SSH_ERR_EXPECTED_CERT;
1289 		}
1290 		if (ret->cert != NULL)
1291 			cert_free(ret->cert);
1292 		ret->cert = k->cert;
1293 		k->cert = NULL;
1294 	}
1295 	switch (sshkey_type_plain(ret->type)) {
1296 #ifdef WITH_OPENSSL
1297 	case KEY_RSA:
1298 		RSA_free(ret->rsa);
1299 		ret->rsa = k->rsa;
1300 		k->rsa = NULL;
1301 #ifdef DEBUG_PK
1302 		RSA_print_fp(stderr, ret->rsa, 8);
1303 #endif
1304 		break;
1305 	case KEY_DSA:
1306 		DSA_free(ret->dsa);
1307 		ret->dsa = k->dsa;
1308 		k->dsa = NULL;
1309 #ifdef DEBUG_PK
1310 		DSA_print_fp(stderr, ret->dsa, 8);
1311 #endif
1312 		break;
1313 	case KEY_ECDSA:
1314 		EC_KEY_free(ret->ecdsa);
1315 		ret->ecdsa = k->ecdsa;
1316 		ret->ecdsa_nid = k->ecdsa_nid;
1317 		k->ecdsa = NULL;
1318 		k->ecdsa_nid = -1;
1319 #ifdef DEBUG_PK
1320 		sshkey_dump_ec_key(ret->ecdsa);
1321 #endif
1322 		break;
1323 #endif /* WITH_OPENSSL */
1324 	case KEY_ED25519:
1325 		freezero(ret->ed25519_pk, ED25519_PK_SZ);
1326 		ret->ed25519_pk = k->ed25519_pk;
1327 		k->ed25519_pk = NULL;
1328 #ifdef DEBUG_PK
1329 		/* XXX */
1330 #endif
1331 		break;
1332 #ifdef WITH_XMSS
1333 	case KEY_XMSS:
1334 		free(ret->xmss_pk);
1335 		ret->xmss_pk = k->xmss_pk;
1336 		k->xmss_pk = NULL;
1337 		free(ret->xmss_state);
1338 		ret->xmss_state = k->xmss_state;
1339 		k->xmss_state = NULL;
1340 		free(ret->xmss_name);
1341 		ret->xmss_name = k->xmss_name;
1342 		k->xmss_name = NULL;
1343 		free(ret->xmss_filename);
1344 		ret->xmss_filename = k->xmss_filename;
1345 		k->xmss_filename = NULL;
1346 #ifdef DEBUG_PK
1347 		/* XXX */
1348 #endif
1349 		break;
1350 #endif /* WITH_XMSS */
1351 	default:
1352 		sshkey_free(k);
1353 		return SSH_ERR_INTERNAL_ERROR;
1354 	}
1355 	sshkey_free(k);
1356 
1357 	/* success */
1358 	*cpp = cp;
1359 	return 0;
1360 }
1361 
1362 int
1363 sshkey_to_base64(const struct sshkey *key, char **b64p)
1364 {
1365 	int r = SSH_ERR_INTERNAL_ERROR;
1366 	struct sshbuf *b = NULL;
1367 	char *uu = NULL;
1368 
1369 	if (b64p != NULL)
1370 		*b64p = NULL;
1371 	if ((b = sshbuf_new()) == NULL)
1372 		return SSH_ERR_ALLOC_FAIL;
1373 	if ((r = sshkey_putb(key, b)) != 0)
1374 		goto out;
1375 	if ((uu = sshbuf_dtob64(b)) == NULL) {
1376 		r = SSH_ERR_ALLOC_FAIL;
1377 		goto out;
1378 	}
1379 	/* Success */
1380 	if (b64p != NULL) {
1381 		*b64p = uu;
1382 		uu = NULL;
1383 	}
1384 	r = 0;
1385  out:
1386 	sshbuf_free(b);
1387 	free(uu);
1388 	return r;
1389 }
1390 
1391 int
1392 sshkey_format_text(const struct sshkey *key, struct sshbuf *b)
1393 {
1394 	int r = SSH_ERR_INTERNAL_ERROR;
1395 	char *uu = NULL;
1396 
1397 	if ((r = sshkey_to_base64(key, &uu)) != 0)
1398 		goto out;
1399 	if ((r = sshbuf_putf(b, "%s %s",
1400 	    sshkey_ssh_name(key), uu)) != 0)
1401 		goto out;
1402 	r = 0;
1403  out:
1404 	free(uu);
1405 	return r;
1406 }
1407 
1408 int
1409 sshkey_write(const struct sshkey *key, FILE *f)
1410 {
1411 	struct sshbuf *b = NULL;
1412 	int r = SSH_ERR_INTERNAL_ERROR;
1413 
1414 	if ((b = sshbuf_new()) == NULL)
1415 		return SSH_ERR_ALLOC_FAIL;
1416 	if ((r = sshkey_format_text(key, b)) != 0)
1417 		goto out;
1418 	if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) {
1419 		if (feof(f))
1420 			errno = EPIPE;
1421 		r = SSH_ERR_SYSTEM_ERROR;
1422 		goto out;
1423 	}
1424 	/* Success */
1425 	r = 0;
1426  out:
1427 	sshbuf_free(b);
1428 	return r;
1429 }
1430 
1431 const char *
1432 sshkey_cert_type(const struct sshkey *k)
1433 {
1434 	switch (k->cert->type) {
1435 	case SSH2_CERT_TYPE_USER:
1436 		return "user";
1437 	case SSH2_CERT_TYPE_HOST:
1438 		return "host";
1439 	default:
1440 		return "unknown";
1441 	}
1442 }
1443 
1444 #ifdef WITH_OPENSSL
1445 static int
1446 rsa_generate_private_key(u_int bits, RSA **rsap)
1447 {
1448 	RSA *private = NULL;
1449 	BIGNUM *f4 = NULL;
1450 	int ret = SSH_ERR_INTERNAL_ERROR;
1451 
1452 	if (rsap == NULL)
1453 		return SSH_ERR_INVALID_ARGUMENT;
1454 	if (bits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
1455 	    bits > SSHBUF_MAX_BIGNUM * 8)
1456 		return SSH_ERR_KEY_LENGTH;
1457 	*rsap = NULL;
1458 	if ((private = RSA_new()) == NULL || (f4 = BN_new()) == NULL) {
1459 		ret = SSH_ERR_ALLOC_FAIL;
1460 		goto out;
1461 	}
1462 	if (!BN_set_word(f4, RSA_F4) ||
1463 	    !RSA_generate_key_ex(private, bits, f4, NULL)) {
1464 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1465 		goto out;
1466 	}
1467 	*rsap = private;
1468 	private = NULL;
1469 	ret = 0;
1470  out:
1471 	RSA_free(private);
1472 	BN_free(f4);
1473 	return ret;
1474 }
1475 
1476 static int
1477 dsa_generate_private_key(u_int bits, DSA **dsap)
1478 {
1479 	DSA *private;
1480 	int ret = SSH_ERR_INTERNAL_ERROR;
1481 
1482 	if (dsap == NULL)
1483 		return SSH_ERR_INVALID_ARGUMENT;
1484 	if (bits != 1024)
1485 		return SSH_ERR_KEY_LENGTH;
1486 	if ((private = DSA_new()) == NULL) {
1487 		ret = SSH_ERR_ALLOC_FAIL;
1488 		goto out;
1489 	}
1490 	*dsap = NULL;
1491 	if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL,
1492 	    NULL, NULL) || !DSA_generate_key(private)) {
1493 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1494 		goto out;
1495 	}
1496 	*dsap = private;
1497 	private = NULL;
1498 	ret = 0;
1499  out:
1500 	DSA_free(private);
1501 	return ret;
1502 }
1503 
1504 int
1505 sshkey_ecdsa_key_to_nid(EC_KEY *k)
1506 {
1507 	EC_GROUP *eg;
1508 	int nids[] = {
1509 		NID_X9_62_prime256v1,
1510 		NID_secp384r1,
1511 		NID_secp521r1,
1512 		-1
1513 	};
1514 	int nid;
1515 	u_int i;
1516 	BN_CTX *bnctx;
1517 	const EC_GROUP *g = EC_KEY_get0_group(k);
1518 
1519 	/*
1520 	 * The group may be stored in a ASN.1 encoded private key in one of two
1521 	 * ways: as a "named group", which is reconstituted by ASN.1 object ID
1522 	 * or explicit group parameters encoded into the key blob. Only the
1523 	 * "named group" case sets the group NID for us, but we can figure
1524 	 * it out for the other case by comparing against all the groups that
1525 	 * are supported.
1526 	 */
1527 	if ((nid = EC_GROUP_get_curve_name(g)) > 0)
1528 		return nid;
1529 	if ((bnctx = BN_CTX_new()) == NULL)
1530 		return -1;
1531 	for (i = 0; nids[i] != -1; i++) {
1532 		if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL) {
1533 			BN_CTX_free(bnctx);
1534 			return -1;
1535 		}
1536 		if (EC_GROUP_cmp(g, eg, bnctx) == 0)
1537 			break;
1538 		EC_GROUP_free(eg);
1539 	}
1540 	BN_CTX_free(bnctx);
1541 	if (nids[i] != -1) {
1542 		/* Use the group with the NID attached */
1543 		EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
1544 		if (EC_KEY_set_group(k, eg) != 1) {
1545 			EC_GROUP_free(eg);
1546 			return -1;
1547 		}
1548 	}
1549 	return nids[i];
1550 }
1551 
1552 static int
1553 ecdsa_generate_private_key(u_int bits, int *nid, EC_KEY **ecdsap)
1554 {
1555 	EC_KEY *private;
1556 	int ret = SSH_ERR_INTERNAL_ERROR;
1557 
1558 	if (nid == NULL || ecdsap == NULL)
1559 		return SSH_ERR_INVALID_ARGUMENT;
1560 	if ((*nid = sshkey_ecdsa_bits_to_nid(bits)) == -1)
1561 		return SSH_ERR_KEY_LENGTH;
1562 	*ecdsap = NULL;
1563 	if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL) {
1564 		ret = SSH_ERR_ALLOC_FAIL;
1565 		goto out;
1566 	}
1567 	if (EC_KEY_generate_key(private) != 1) {
1568 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1569 		goto out;
1570 	}
1571 	EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE);
1572 	*ecdsap = private;
1573 	private = NULL;
1574 	ret = 0;
1575  out:
1576 	EC_KEY_free(private);
1577 	return ret;
1578 }
1579 #endif /* WITH_OPENSSL */
1580 
1581 int
1582 sshkey_generate(int type, u_int bits, struct sshkey **keyp)
1583 {
1584 	struct sshkey *k;
1585 	int ret = SSH_ERR_INTERNAL_ERROR;
1586 
1587 	if (keyp == NULL)
1588 		return SSH_ERR_INVALID_ARGUMENT;
1589 	*keyp = NULL;
1590 	if ((k = sshkey_new(KEY_UNSPEC)) == NULL)
1591 		return SSH_ERR_ALLOC_FAIL;
1592 	switch (type) {
1593 	case KEY_ED25519:
1594 		if ((k->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL ||
1595 		    (k->ed25519_sk = malloc(ED25519_SK_SZ)) == NULL) {
1596 			ret = SSH_ERR_ALLOC_FAIL;
1597 			break;
1598 		}
1599 		crypto_sign_ed25519_keypair(k->ed25519_pk, k->ed25519_sk);
1600 		ret = 0;
1601 		break;
1602 #ifdef WITH_XMSS
1603 	case KEY_XMSS:
1604 		ret = sshkey_xmss_generate_private_key(k, bits);
1605 		break;
1606 #endif /* WITH_XMSS */
1607 #ifdef WITH_OPENSSL
1608 	case KEY_DSA:
1609 		ret = dsa_generate_private_key(bits, &k->dsa);
1610 		break;
1611 	case KEY_ECDSA:
1612 		ret = ecdsa_generate_private_key(bits, &k->ecdsa_nid,
1613 		    &k->ecdsa);
1614 		break;
1615 	case KEY_RSA:
1616 		ret = rsa_generate_private_key(bits, &k->rsa);
1617 		break;
1618 #endif /* WITH_OPENSSL */
1619 	default:
1620 		ret = SSH_ERR_INVALID_ARGUMENT;
1621 	}
1622 	if (ret == 0) {
1623 		k->type = type;
1624 		*keyp = k;
1625 	} else
1626 		sshkey_free(k);
1627 	return ret;
1628 }
1629 
1630 int
1631 sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key)
1632 {
1633 	u_int i;
1634 	const struct sshkey_cert *from;
1635 	struct sshkey_cert *to;
1636 	int r = SSH_ERR_INTERNAL_ERROR;
1637 
1638 	if (to_key == NULL || (from = from_key->cert) == NULL)
1639 		return SSH_ERR_INVALID_ARGUMENT;
1640 
1641 	if ((to = cert_new()) == NULL)
1642 		return SSH_ERR_ALLOC_FAIL;
1643 
1644 	if ((r = sshbuf_putb(to->certblob, from->certblob)) != 0 ||
1645 	    (r = sshbuf_putb(to->critical, from->critical)) != 0 ||
1646 	    (r = sshbuf_putb(to->extensions, from->extensions)) != 0)
1647 		goto out;
1648 
1649 	to->serial = from->serial;
1650 	to->type = from->type;
1651 	if (from->key_id == NULL)
1652 		to->key_id = NULL;
1653 	else if ((to->key_id = strdup(from->key_id)) == NULL) {
1654 		r = SSH_ERR_ALLOC_FAIL;
1655 		goto out;
1656 	}
1657 	to->valid_after = from->valid_after;
1658 	to->valid_before = from->valid_before;
1659 	if (from->signature_key == NULL)
1660 		to->signature_key = NULL;
1661 	else if ((r = sshkey_from_private(from->signature_key,
1662 	    &to->signature_key)) != 0)
1663 		goto out;
1664 	if (from->signature_type != NULL &&
1665 	    (to->signature_type = strdup(from->signature_type)) == NULL) {
1666 		r = SSH_ERR_ALLOC_FAIL;
1667 		goto out;
1668 	}
1669 	if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS) {
1670 		r = SSH_ERR_INVALID_ARGUMENT;
1671 		goto out;
1672 	}
1673 	if (from->nprincipals > 0) {
1674 		if ((to->principals = calloc(from->nprincipals,
1675 		    sizeof(*to->principals))) == NULL) {
1676 			r = SSH_ERR_ALLOC_FAIL;
1677 			goto out;
1678 		}
1679 		for (i = 0; i < from->nprincipals; i++) {
1680 			to->principals[i] = strdup(from->principals[i]);
1681 			if (to->principals[i] == NULL) {
1682 				to->nprincipals = i;
1683 				r = SSH_ERR_ALLOC_FAIL;
1684 				goto out;
1685 			}
1686 		}
1687 	}
1688 	to->nprincipals = from->nprincipals;
1689 
1690 	/* success */
1691 	cert_free(to_key->cert);
1692 	to_key->cert = to;
1693 	to = NULL;
1694 	r = 0;
1695  out:
1696 	cert_free(to);
1697 	return r;
1698 }
1699 
1700 int
1701 sshkey_from_private(const struct sshkey *k, struct sshkey **pkp)
1702 {
1703 	struct sshkey *n = NULL;
1704 	int r = SSH_ERR_INTERNAL_ERROR;
1705 #ifdef WITH_OPENSSL
1706 	const BIGNUM *rsa_n, *rsa_e;
1707 	BIGNUM *rsa_n_dup = NULL, *rsa_e_dup = NULL;
1708 	const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
1709 	BIGNUM *dsa_p_dup = NULL, *dsa_q_dup = NULL, *dsa_g_dup = NULL;
1710 	BIGNUM *dsa_pub_key_dup = NULL;
1711 #endif /* WITH_OPENSSL */
1712 
1713 	*pkp = NULL;
1714 	switch (k->type) {
1715 #ifdef WITH_OPENSSL
1716 	case KEY_DSA:
1717 	case KEY_DSA_CERT:
1718 		if ((n = sshkey_new(k->type)) == NULL) {
1719 			r = SSH_ERR_ALLOC_FAIL;
1720 			goto out;
1721 		}
1722 
1723 		DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g);
1724 		DSA_get0_key(k->dsa, &dsa_pub_key, NULL);
1725 		if ((dsa_p_dup = BN_dup(dsa_p)) == NULL ||
1726 		    (dsa_q_dup = BN_dup(dsa_q)) == NULL ||
1727 		    (dsa_g_dup = BN_dup(dsa_g)) == NULL ||
1728 		    (dsa_pub_key_dup = BN_dup(dsa_pub_key)) == NULL) {
1729 			r = SSH_ERR_ALLOC_FAIL;
1730 			goto out;
1731 		}
1732 		if (!DSA_set0_pqg(n->dsa, dsa_p_dup, dsa_q_dup, dsa_g_dup)) {
1733 			r = SSH_ERR_LIBCRYPTO_ERROR;
1734 			goto out;
1735 		}
1736 		dsa_p_dup = dsa_q_dup = dsa_g_dup = NULL; /* transferred */
1737 		if (!DSA_set0_key(n->dsa, dsa_pub_key_dup, NULL)) {
1738 			r = SSH_ERR_LIBCRYPTO_ERROR;
1739 			goto out;
1740 		}
1741 		dsa_pub_key_dup = NULL; /* transferred */
1742 
1743 		break;
1744 	case KEY_ECDSA:
1745 	case KEY_ECDSA_CERT:
1746 		if ((n = sshkey_new(k->type)) == NULL) {
1747 			r = SSH_ERR_ALLOC_FAIL;
1748 			goto out;
1749 		}
1750 		n->ecdsa_nid = k->ecdsa_nid;
1751 		n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
1752 		if (n->ecdsa == NULL) {
1753 			r = SSH_ERR_ALLOC_FAIL;
1754 			goto out;
1755 		}
1756 		if (EC_KEY_set_public_key(n->ecdsa,
1757 		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
1758 			r = SSH_ERR_LIBCRYPTO_ERROR;
1759 			goto out;
1760 		}
1761 		break;
1762 	case KEY_RSA:
1763 	case KEY_RSA_CERT:
1764 		if ((n = sshkey_new(k->type)) == NULL) {
1765 			r = SSH_ERR_ALLOC_FAIL;
1766 			goto out;
1767 		}
1768 		RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL);
1769 		if ((rsa_n_dup = BN_dup(rsa_n)) == NULL ||
1770 		    (rsa_e_dup = BN_dup(rsa_e)) == NULL) {
1771 			r = SSH_ERR_ALLOC_FAIL;
1772 			goto out;
1773 		}
1774 		if (!RSA_set0_key(n->rsa, rsa_n_dup, rsa_e_dup, NULL)) {
1775 			r = SSH_ERR_LIBCRYPTO_ERROR;
1776 			goto out;
1777 		}
1778 		rsa_n_dup = rsa_e_dup = NULL; /* transferred */
1779 		break;
1780 #endif /* WITH_OPENSSL */
1781 	case KEY_ED25519:
1782 	case KEY_ED25519_CERT:
1783 		if ((n = sshkey_new(k->type)) == NULL) {
1784 			r = SSH_ERR_ALLOC_FAIL;
1785 			goto out;
1786 		}
1787 		if (k->ed25519_pk != NULL) {
1788 			if ((n->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
1789 				r = SSH_ERR_ALLOC_FAIL;
1790 				goto out;
1791 			}
1792 			memcpy(n->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
1793 		}
1794 		break;
1795 #ifdef WITH_XMSS
1796 	case KEY_XMSS:
1797 	case KEY_XMSS_CERT:
1798 		if ((n = sshkey_new(k->type)) == NULL) {
1799 			r = SSH_ERR_ALLOC_FAIL;
1800 			goto out;
1801 		}
1802 		if ((r = sshkey_xmss_init(n, k->xmss_name)) != 0)
1803 			goto out;
1804 		if (k->xmss_pk != NULL) {
1805 			size_t pklen = sshkey_xmss_pklen(k);
1806 			if (pklen == 0 || sshkey_xmss_pklen(n) != pklen) {
1807 				r = SSH_ERR_INTERNAL_ERROR;
1808 				goto out;
1809 			}
1810 			if ((n->xmss_pk = malloc(pklen)) == NULL) {
1811 				r = SSH_ERR_ALLOC_FAIL;
1812 				goto out;
1813 			}
1814 			memcpy(n->xmss_pk, k->xmss_pk, pklen);
1815 		}
1816 		break;
1817 #endif /* WITH_XMSS */
1818 	default:
1819 		r = SSH_ERR_KEY_TYPE_UNKNOWN;
1820 		goto out;
1821 	}
1822 	if (sshkey_is_cert(k) && (r = sshkey_cert_copy(k, n)) != 0)
1823 		goto out;
1824 	/* success */
1825 	*pkp = n;
1826 	n = NULL;
1827 	r = 0;
1828  out:
1829 	sshkey_free(n);
1830 	BN_clear_free(rsa_n_dup);
1831 	BN_clear_free(rsa_e_dup);
1832 	BN_clear_free(dsa_p_dup);
1833 	BN_clear_free(dsa_q_dup);
1834 	BN_clear_free(dsa_g_dup);
1835 	BN_clear_free(dsa_pub_key_dup);
1836 
1837 	return r;
1838 }
1839 
1840 int
1841 sshkey_is_shielded(struct sshkey *k)
1842 {
1843 	return k != NULL && k->shielded_private != NULL;
1844 }
1845 
1846 int
1847 sshkey_shield_private(struct sshkey *k)
1848 {
1849 	struct sshbuf *prvbuf = NULL;
1850 	u_char *prekey = NULL, *enc = NULL, keyiv[SSH_DIGEST_MAX_LENGTH];
1851 	struct sshcipher_ctx *cctx = NULL;
1852 	const struct sshcipher *cipher;
1853 	size_t i, enclen = 0;
1854 	struct sshkey *kswap = NULL, tmp;
1855 	int r = SSH_ERR_INTERNAL_ERROR;
1856 
1857 #ifdef DEBUG_PK
1858 	fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k));
1859 #endif
1860 	if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) {
1861 		r = SSH_ERR_INVALID_ARGUMENT;
1862 		goto out;
1863 	}
1864 	if (cipher_keylen(cipher) + cipher_ivlen(cipher) >
1865 	    ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) {
1866 		r = SSH_ERR_INTERNAL_ERROR;
1867 		goto out;
1868 	}
1869 
1870 	/* Prepare a random pre-key, and from it an ephemeral key */
1871 	if ((prekey = malloc(SSHKEY_SHIELD_PREKEY_LEN)) == NULL) {
1872 		r = SSH_ERR_ALLOC_FAIL;
1873 		goto out;
1874 	}
1875 	arc4random_buf(prekey, SSHKEY_SHIELD_PREKEY_LEN);
1876 	if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH,
1877 	    prekey, SSHKEY_SHIELD_PREKEY_LEN,
1878 	    keyiv, SSH_DIGEST_MAX_LENGTH)) != 0)
1879 		goto out;
1880 #ifdef DEBUG_PK
1881 	fprintf(stderr, "%s: key+iv\n", __func__);
1882 	sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH),
1883 	    stderr);
1884 #endif
1885 	if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher),
1886 	    keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 1)) != 0)
1887 		goto out;
1888 
1889 	/* Serialise and encrypt the private key using the ephemeral key */
1890 	if ((prvbuf = sshbuf_new()) == NULL) {
1891 		r = SSH_ERR_ALLOC_FAIL;
1892 		goto out;
1893 	}
1894 	if (sshkey_is_shielded(k) && (r = sshkey_unshield_private(k)) != 0)
1895 		goto out;
1896 	if ((r = sshkey_private_serialize_opt(k, prvbuf,
1897 	     SSHKEY_SERIALIZE_FULL)) != 0)
1898 		goto out;
1899 	/* pad to cipher blocksize */
1900 	i = 0;
1901 	while (sshbuf_len(prvbuf) % cipher_blocksize(cipher)) {
1902 		if ((r = sshbuf_put_u8(prvbuf, ++i & 0xff)) != 0)
1903 			goto out;
1904 	}
1905 #ifdef DEBUG_PK
1906 	fprintf(stderr, "%s: serialised\n", __func__);
1907 	sshbuf_dump(prvbuf, stderr);
1908 #endif
1909 	/* encrypt */
1910 	enclen = sshbuf_len(prvbuf);
1911 	if ((enc = malloc(enclen)) == NULL) {
1912 		r = SSH_ERR_ALLOC_FAIL;
1913 		goto out;
1914 	}
1915 	if ((r = cipher_crypt(cctx, 0, enc,
1916 	    sshbuf_ptr(prvbuf), sshbuf_len(prvbuf), 0, 0)) != 0)
1917 		goto out;
1918 #ifdef DEBUG_PK
1919 	fprintf(stderr, "%s: encrypted\n", __func__);
1920 	sshbuf_dump_data(enc, enclen, stderr);
1921 #endif
1922 
1923 	/* Make a scrubbed, public-only copy of our private key argument */
1924 	if ((r = sshkey_from_private(k, &kswap)) != 0)
1925 		goto out;
1926 
1927 	/* Swap the private key out (it will be destroyed below) */
1928 	tmp = *kswap;
1929 	*kswap = *k;
1930 	*k = tmp;
1931 
1932 	/* Insert the shielded key into our argument */
1933 	k->shielded_private = enc;
1934 	k->shielded_len = enclen;
1935 	k->shield_prekey = prekey;
1936 	k->shield_prekey_len = SSHKEY_SHIELD_PREKEY_LEN;
1937 	enc = prekey = NULL; /* transferred */
1938 	enclen = 0;
1939 
1940 	/* success */
1941 	r = 0;
1942 
1943  out:
1944 	/* XXX behaviour on error - invalidate original private key? */
1945 	cipher_free(cctx);
1946 	explicit_bzero(enc, enclen);
1947 	explicit_bzero(keyiv, sizeof(keyiv));
1948 	explicit_bzero(&tmp, sizeof(tmp));
1949 	freezero(prekey, SSHKEY_SHIELD_PREKEY_LEN);
1950 	sshkey_free(kswap);
1951 	sshbuf_free(prvbuf);
1952 	return r;
1953 }
1954 
1955 int
1956 sshkey_unshield_private(struct sshkey *k)
1957 {
1958 	struct sshbuf *prvbuf = NULL;
1959 	u_char pad, *cp, keyiv[SSH_DIGEST_MAX_LENGTH];
1960 	struct sshcipher_ctx *cctx = NULL;
1961 	const struct sshcipher *cipher;
1962 	size_t i;
1963 	struct sshkey *kswap = NULL, tmp;
1964 	int r = SSH_ERR_INTERNAL_ERROR;
1965 
1966 #ifdef DEBUG_PK
1967 	fprintf(stderr, "%s: entering for %s\n", __func__, sshkey_ssh_name(k));
1968 #endif
1969 	if (!sshkey_is_shielded(k))
1970 		return 0; /* nothing to do */
1971 
1972 	if ((cipher = cipher_by_name(SSHKEY_SHIELD_CIPHER)) == NULL) {
1973 		r = SSH_ERR_INVALID_ARGUMENT;
1974 		goto out;
1975 	}
1976 	if (cipher_keylen(cipher) + cipher_ivlen(cipher) >
1977 	    ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH)) {
1978 		r = SSH_ERR_INTERNAL_ERROR;
1979 		goto out;
1980 	}
1981 	/* check size of shielded key blob */
1982 	if (k->shielded_len < cipher_blocksize(cipher) ||
1983 	    (k->shielded_len % cipher_blocksize(cipher)) != 0) {
1984 		r = SSH_ERR_INVALID_FORMAT;
1985 		goto out;
1986 	}
1987 
1988 	/* Calculate the ephemeral key from the prekey */
1989 	if ((r = ssh_digest_memory(SSHKEY_SHIELD_PREKEY_HASH,
1990 	    k->shield_prekey, k->shield_prekey_len,
1991 	    keyiv, SSH_DIGEST_MAX_LENGTH)) != 0)
1992 		goto out;
1993 	if ((r = cipher_init(&cctx, cipher, keyiv, cipher_keylen(cipher),
1994 	    keyiv + cipher_keylen(cipher), cipher_ivlen(cipher), 0)) != 0)
1995 		goto out;
1996 #ifdef DEBUG_PK
1997 	fprintf(stderr, "%s: key+iv\n", __func__);
1998 	sshbuf_dump_data(keyiv, ssh_digest_bytes(SSHKEY_SHIELD_PREKEY_HASH),
1999 	    stderr);
2000 #endif
2001 
2002 	/* Decrypt and parse the shielded private key using the ephemeral key */
2003 	if ((prvbuf = sshbuf_new()) == NULL) {
2004 		r = SSH_ERR_ALLOC_FAIL;
2005 		goto out;
2006 	}
2007 	if ((r = sshbuf_reserve(prvbuf, k->shielded_len, &cp)) != 0)
2008 		goto out;
2009 	/* decrypt */
2010 #ifdef DEBUG_PK
2011 	fprintf(stderr, "%s: encrypted\n", __func__);
2012 	sshbuf_dump_data(k->shielded_private, k->shielded_len, stderr);
2013 #endif
2014 	if ((r = cipher_crypt(cctx, 0, cp,
2015 	    k->shielded_private, k->shielded_len, 0, 0)) != 0)
2016 		goto out;
2017 #ifdef DEBUG_PK
2018 	fprintf(stderr, "%s: serialised\n", __func__);
2019 	sshbuf_dump(prvbuf, stderr);
2020 #endif
2021 	/* Parse private key */
2022 	if ((r = sshkey_private_deserialize(prvbuf, &kswap)) != 0)
2023 		goto out;
2024 	/* Check deterministic padding */
2025 	i = 0;
2026 	while (sshbuf_len(prvbuf)) {
2027 		if ((r = sshbuf_get_u8(prvbuf, &pad)) != 0)
2028 			goto out;
2029 		if (pad != (++i & 0xff)) {
2030 			r = SSH_ERR_INVALID_FORMAT;
2031 			goto out;
2032 		}
2033 	}
2034 
2035 	/* Swap the parsed key back into place */
2036 	tmp = *kswap;
2037 	*kswap = *k;
2038 	*k = tmp;
2039 
2040 	/* success */
2041 	r = 0;
2042 
2043  out:
2044 	cipher_free(cctx);
2045 	explicit_bzero(keyiv, sizeof(keyiv));
2046 	explicit_bzero(&tmp, sizeof(tmp));
2047 	sshkey_free(kswap);
2048 	sshbuf_free(prvbuf);
2049 	return r;
2050 }
2051 
2052 static int
2053 cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
2054 {
2055 	struct sshbuf *principals = NULL, *crit = NULL;
2056 	struct sshbuf *exts = NULL, *ca = NULL;
2057 	u_char *sig = NULL;
2058 	size_t signed_len = 0, slen = 0, kidlen = 0;
2059 	int ret = SSH_ERR_INTERNAL_ERROR;
2060 
2061 	/* Copy the entire key blob for verification and later serialisation */
2062 	if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0)
2063 		return ret;
2064 
2065 	/* Parse body of certificate up to signature */
2066 	if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 ||
2067 	    (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 ||
2068 	    (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 ||
2069 	    (ret = sshbuf_froms(b, &principals)) != 0 ||
2070 	    (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 ||
2071 	    (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 ||
2072 	    (ret = sshbuf_froms(b, &crit)) != 0 ||
2073 	    (ret = sshbuf_froms(b, &exts)) != 0 ||
2074 	    (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 ||
2075 	    (ret = sshbuf_froms(b, &ca)) != 0) {
2076 		/* XXX debug print error for ret */
2077 		ret = SSH_ERR_INVALID_FORMAT;
2078 		goto out;
2079 	}
2080 
2081 	/* Signature is left in the buffer so we can calculate this length */
2082 	signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b);
2083 
2084 	if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) {
2085 		ret = SSH_ERR_INVALID_FORMAT;
2086 		goto out;
2087 	}
2088 
2089 	if (key->cert->type != SSH2_CERT_TYPE_USER &&
2090 	    key->cert->type != SSH2_CERT_TYPE_HOST) {
2091 		ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE;
2092 		goto out;
2093 	}
2094 
2095 	/* Parse principals section */
2096 	while (sshbuf_len(principals) > 0) {
2097 		char *principal = NULL;
2098 		char **oprincipals = NULL;
2099 
2100 		if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) {
2101 			ret = SSH_ERR_INVALID_FORMAT;
2102 			goto out;
2103 		}
2104 		if ((ret = sshbuf_get_cstring(principals, &principal,
2105 		    NULL)) != 0) {
2106 			ret = SSH_ERR_INVALID_FORMAT;
2107 			goto out;
2108 		}
2109 		oprincipals = key->cert->principals;
2110 		key->cert->principals = recallocarray(key->cert->principals,
2111 		    key->cert->nprincipals, key->cert->nprincipals + 1,
2112 		    sizeof(*key->cert->principals));
2113 		if (key->cert->principals == NULL) {
2114 			free(principal);
2115 			key->cert->principals = oprincipals;
2116 			ret = SSH_ERR_ALLOC_FAIL;
2117 			goto out;
2118 		}
2119 		key->cert->principals[key->cert->nprincipals++] = principal;
2120 	}
2121 
2122 	/*
2123 	 * Stash a copies of the critical options and extensions sections
2124 	 * for later use.
2125 	 */
2126 	if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 ||
2127 	    (exts != NULL &&
2128 	    (ret = sshbuf_putb(key->cert->extensions, exts)) != 0))
2129 		goto out;
2130 
2131 	/*
2132 	 * Validate critical options and extensions sections format.
2133 	 */
2134 	while (sshbuf_len(crit) != 0) {
2135 		if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 ||
2136 		    (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) {
2137 			sshbuf_reset(key->cert->critical);
2138 			ret = SSH_ERR_INVALID_FORMAT;
2139 			goto out;
2140 		}
2141 	}
2142 	while (exts != NULL && sshbuf_len(exts) != 0) {
2143 		if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 ||
2144 		    (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) {
2145 			sshbuf_reset(key->cert->extensions);
2146 			ret = SSH_ERR_INVALID_FORMAT;
2147 			goto out;
2148 		}
2149 	}
2150 
2151 	/* Parse CA key and check signature */
2152 	if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) {
2153 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2154 		goto out;
2155 	}
2156 	if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) {
2157 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2158 		goto out;
2159 	}
2160 	if ((ret = sshkey_verify(key->cert->signature_key, sig, slen,
2161 	    sshbuf_ptr(key->cert->certblob), signed_len, NULL, 0)) != 0)
2162 		goto out;
2163 	if ((ret = get_sigtype(sig, slen, &key->cert->signature_type)) != 0)
2164 		goto out;
2165 
2166 	/* Success */
2167 	ret = 0;
2168  out:
2169 	sshbuf_free(ca);
2170 	sshbuf_free(crit);
2171 	sshbuf_free(exts);
2172 	sshbuf_free(principals);
2173 	free(sig);
2174 	return ret;
2175 }
2176 
2177 static int
2178 check_rsa_length(const RSA *rsa)
2179 {
2180 	const BIGNUM *rsa_n;
2181 
2182 	RSA_get0_key(rsa, &rsa_n, NULL, NULL);
2183 	if (BN_num_bits(rsa_n) < SSH_RSA_MINIMUM_MODULUS_SIZE)
2184 		return SSH_ERR_KEY_LENGTH;
2185 	return 0;
2186 }
2187 
2188 static int
2189 sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
2190     int allow_cert)
2191 {
2192 	int type, ret = SSH_ERR_INTERNAL_ERROR;
2193 	char *ktype = NULL, *curve = NULL, *xmss_name = NULL;
2194 	struct sshkey *key = NULL;
2195 	size_t len;
2196 	u_char *pk = NULL;
2197 	struct sshbuf *copy;
2198 #ifdef WITH_OPENSSL
2199 	EC_POINT *q = NULL;
2200 	BIGNUM *rsa_n = NULL, *rsa_e = NULL;
2201 	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL, *dsa_pub_key = NULL;
2202 #endif /* WITH_OPENSSL */
2203 
2204 #ifdef DEBUG_PK /* XXX */
2205 	sshbuf_dump(b, stderr);
2206 #endif
2207 	if (keyp != NULL)
2208 		*keyp = NULL;
2209 	if ((copy = sshbuf_fromb(b)) == NULL) {
2210 		ret = SSH_ERR_ALLOC_FAIL;
2211 		goto out;
2212 	}
2213 	if (sshbuf_get_cstring(b, &ktype, NULL) != 0) {
2214 		ret = SSH_ERR_INVALID_FORMAT;
2215 		goto out;
2216 	}
2217 
2218 	type = sshkey_type_from_name(ktype);
2219 	if (!allow_cert && sshkey_type_is_cert(type)) {
2220 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2221 		goto out;
2222 	}
2223 	switch (type) {
2224 #ifdef WITH_OPENSSL
2225 	case KEY_RSA_CERT:
2226 		/* Skip nonce */
2227 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2228 			ret = SSH_ERR_INVALID_FORMAT;
2229 			goto out;
2230 		}
2231 		/* FALLTHROUGH */
2232 	case KEY_RSA:
2233 		if ((key = sshkey_new(type)) == NULL) {
2234 			ret = SSH_ERR_ALLOC_FAIL;
2235 			goto out;
2236 		}
2237 		if (sshbuf_get_bignum2(b, &rsa_e) != 0 ||
2238 		    sshbuf_get_bignum2(b, &rsa_n) != 0) {
2239 			ret = SSH_ERR_INVALID_FORMAT;
2240 			goto out;
2241 		}
2242 		if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, NULL)) {
2243 			ret = SSH_ERR_LIBCRYPTO_ERROR;
2244 			goto out;
2245 		}
2246 		rsa_n = rsa_e = NULL; /* transferred */
2247 		if ((ret = check_rsa_length(key->rsa)) != 0)
2248 			goto out;
2249 #ifdef DEBUG_PK
2250 		RSA_print_fp(stderr, key->rsa, 8);
2251 #endif
2252 		break;
2253 	case KEY_DSA_CERT:
2254 		/* Skip nonce */
2255 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2256 			ret = SSH_ERR_INVALID_FORMAT;
2257 			goto out;
2258 		}
2259 		/* FALLTHROUGH */
2260 	case KEY_DSA:
2261 		if ((key = sshkey_new(type)) == NULL) {
2262 			ret = SSH_ERR_ALLOC_FAIL;
2263 			goto out;
2264 		}
2265 		if (sshbuf_get_bignum2(b, &dsa_p) != 0 ||
2266 		    sshbuf_get_bignum2(b, &dsa_q) != 0 ||
2267 		    sshbuf_get_bignum2(b, &dsa_g) != 0 ||
2268 		    sshbuf_get_bignum2(b, &dsa_pub_key) != 0) {
2269 			ret = SSH_ERR_INVALID_FORMAT;
2270 			goto out;
2271 		}
2272 		if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g)) {
2273 			ret = SSH_ERR_LIBCRYPTO_ERROR;
2274 			goto out;
2275 		}
2276 		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
2277 		if (!DSA_set0_key(key->dsa, dsa_pub_key, NULL)) {
2278 			ret = SSH_ERR_LIBCRYPTO_ERROR;
2279 			goto out;
2280 		}
2281 		dsa_pub_key = NULL; /* transferred */
2282 #ifdef DEBUG_PK
2283 		DSA_print_fp(stderr, key->dsa, 8);
2284 #endif
2285 		break;
2286 	case KEY_ECDSA_CERT:
2287 		/* Skip nonce */
2288 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2289 			ret = SSH_ERR_INVALID_FORMAT;
2290 			goto out;
2291 		}
2292 		/* FALLTHROUGH */
2293 	case KEY_ECDSA:
2294 		if ((key = sshkey_new(type)) == NULL) {
2295 			ret = SSH_ERR_ALLOC_FAIL;
2296 			goto out;
2297 		}
2298 		key->ecdsa_nid = sshkey_ecdsa_nid_from_name(ktype);
2299 		if (sshbuf_get_cstring(b, &curve, NULL) != 0) {
2300 			ret = SSH_ERR_INVALID_FORMAT;
2301 			goto out;
2302 		}
2303 		if (key->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
2304 			ret = SSH_ERR_EC_CURVE_MISMATCH;
2305 			goto out;
2306 		}
2307 		EC_KEY_free(key->ecdsa);
2308 		if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
2309 		    == NULL) {
2310 			ret = SSH_ERR_EC_CURVE_INVALID;
2311 			goto out;
2312 		}
2313 		if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL) {
2314 			ret = SSH_ERR_ALLOC_FAIL;
2315 			goto out;
2316 		}
2317 		if (sshbuf_get_ec(b, q, EC_KEY_get0_group(key->ecdsa)) != 0) {
2318 			ret = SSH_ERR_INVALID_FORMAT;
2319 			goto out;
2320 		}
2321 		if (sshkey_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
2322 		    q) != 0) {
2323 			ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2324 			goto out;
2325 		}
2326 		if (EC_KEY_set_public_key(key->ecdsa, q) != 1) {
2327 			/* XXX assume it is a allocation error */
2328 			ret = SSH_ERR_ALLOC_FAIL;
2329 			goto out;
2330 		}
2331 #ifdef DEBUG_PK
2332 		sshkey_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
2333 #endif
2334 		break;
2335 #endif /* WITH_OPENSSL */
2336 	case KEY_ED25519_CERT:
2337 		/* Skip nonce */
2338 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2339 			ret = SSH_ERR_INVALID_FORMAT;
2340 			goto out;
2341 		}
2342 		/* FALLTHROUGH */
2343 	case KEY_ED25519:
2344 		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
2345 			goto out;
2346 		if (len != ED25519_PK_SZ) {
2347 			ret = SSH_ERR_INVALID_FORMAT;
2348 			goto out;
2349 		}
2350 		if ((key = sshkey_new(type)) == NULL) {
2351 			ret = SSH_ERR_ALLOC_FAIL;
2352 			goto out;
2353 		}
2354 		key->ed25519_pk = pk;
2355 		pk = NULL;
2356 		break;
2357 #ifdef WITH_XMSS
2358 	case KEY_XMSS_CERT:
2359 		/* Skip nonce */
2360 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2361 			ret = SSH_ERR_INVALID_FORMAT;
2362 			goto out;
2363 		}
2364 		/* FALLTHROUGH */
2365 	case KEY_XMSS:
2366 		if ((ret = sshbuf_get_cstring(b, &xmss_name, NULL)) != 0)
2367 			goto out;
2368 		if ((key = sshkey_new(type)) == NULL) {
2369 			ret = SSH_ERR_ALLOC_FAIL;
2370 			goto out;
2371 		}
2372 		if ((ret = sshkey_xmss_init(key, xmss_name)) != 0)
2373 			goto out;
2374 		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
2375 			goto out;
2376 		if (len == 0 || len != sshkey_xmss_pklen(key)) {
2377 			ret = SSH_ERR_INVALID_FORMAT;
2378 			goto out;
2379 		}
2380 		key->xmss_pk = pk;
2381 		pk = NULL;
2382 		if (type != KEY_XMSS_CERT &&
2383 		    (ret = sshkey_xmss_deserialize_pk_info(key, b)) != 0)
2384 			goto out;
2385 		break;
2386 #endif /* WITH_XMSS */
2387 	case KEY_UNSPEC:
2388 	default:
2389 		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
2390 		goto out;
2391 	}
2392 
2393 	/* Parse certificate potion */
2394 	if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0)
2395 		goto out;
2396 
2397 	if (key != NULL && sshbuf_len(b) != 0) {
2398 		ret = SSH_ERR_INVALID_FORMAT;
2399 		goto out;
2400 	}
2401 	ret = 0;
2402 	if (keyp != NULL) {
2403 		*keyp = key;
2404 		key = NULL;
2405 	}
2406  out:
2407 	sshbuf_free(copy);
2408 	sshkey_free(key);
2409 	free(xmss_name);
2410 	free(ktype);
2411 	free(curve);
2412 	free(pk);
2413 #ifdef WITH_OPENSSL
2414 	EC_POINT_free(q);
2415 	BN_clear_free(rsa_n);
2416 	BN_clear_free(rsa_e);
2417 	BN_clear_free(dsa_p);
2418 	BN_clear_free(dsa_q);
2419 	BN_clear_free(dsa_g);
2420 	BN_clear_free(dsa_pub_key);
2421 #endif /* WITH_OPENSSL */
2422 	return ret;
2423 }
2424 
2425 int
2426 sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp)
2427 {
2428 	struct sshbuf *b;
2429 	int r;
2430 
2431 	if ((b = sshbuf_from(blob, blen)) == NULL)
2432 		return SSH_ERR_ALLOC_FAIL;
2433 	r = sshkey_from_blob_internal(b, keyp, 1);
2434 	sshbuf_free(b);
2435 	return r;
2436 }
2437 
2438 int
2439 sshkey_fromb(struct sshbuf *b, struct sshkey **keyp)
2440 {
2441 	return sshkey_from_blob_internal(b, keyp, 1);
2442 }
2443 
2444 int
2445 sshkey_froms(struct sshbuf *buf, struct sshkey **keyp)
2446 {
2447 	struct sshbuf *b;
2448 	int r;
2449 
2450 	if ((r = sshbuf_froms(buf, &b)) != 0)
2451 		return r;
2452 	r = sshkey_from_blob_internal(b, keyp, 1);
2453 	sshbuf_free(b);
2454 	return r;
2455 }
2456 
2457 static int
2458 get_sigtype(const u_char *sig, size_t siglen, char **sigtypep)
2459 {
2460 	int r;
2461 	struct sshbuf *b = NULL;
2462 	char *sigtype = NULL;
2463 
2464 	if (sigtypep != NULL)
2465 		*sigtypep = NULL;
2466 	if ((b = sshbuf_from(sig, siglen)) == NULL)
2467 		return SSH_ERR_ALLOC_FAIL;
2468 	if ((r = sshbuf_get_cstring(b, &sigtype, NULL)) != 0)
2469 		goto out;
2470 	/* success */
2471 	if (sigtypep != NULL) {
2472 		*sigtypep = sigtype;
2473 		sigtype = NULL;
2474 	}
2475 	r = 0;
2476  out:
2477 	free(sigtype);
2478 	sshbuf_free(b);
2479 	return r;
2480 }
2481 
2482 /*
2483  *
2484  * Checks whether a certificate's signature type is allowed.
2485  * Returns 0 (success) if the certificate signature type appears in the
2486  * "allowed" pattern-list, or the key is not a certificate to begin with.
2487  * Otherwise returns a ssherr.h code.
2488  */
2489 int
2490 sshkey_check_cert_sigtype(const struct sshkey *key, const char *allowed)
2491 {
2492 	if (key == NULL || allowed == NULL)
2493 		return SSH_ERR_INVALID_ARGUMENT;
2494 	if (!sshkey_type_is_cert(key->type))
2495 		return 0;
2496 	if (key->cert == NULL || key->cert->signature_type == NULL)
2497 		return SSH_ERR_INVALID_ARGUMENT;
2498 	if (match_pattern_list(key->cert->signature_type, allowed, 0) != 1)
2499 		return SSH_ERR_SIGN_ALG_UNSUPPORTED;
2500 	return 0;
2501 }
2502 
2503 /*
2504  * Returns the expected signature algorithm for a given public key algorithm.
2505  */
2506 const char *
2507 sshkey_sigalg_by_name(const char *name)
2508 {
2509 	const struct keytype *kt;
2510 
2511 	for (kt = keytypes; kt->type != -1; kt++) {
2512 		if (strcmp(kt->name, name) != 0)
2513 			continue;
2514 		if (kt->sigalg != NULL)
2515 			return kt->sigalg;
2516 		if (!kt->cert)
2517 			return kt->name;
2518 		return sshkey_ssh_name_from_type_nid(
2519 		    sshkey_type_plain(kt->type), kt->nid);
2520 	}
2521 	return NULL;
2522 }
2523 
2524 /*
2525  * Verifies that the signature algorithm appearing inside the signature blob
2526  * matches that which was requested.
2527  */
2528 int
2529 sshkey_check_sigtype(const u_char *sig, size_t siglen,
2530     const char *requested_alg)
2531 {
2532 	const char *expected_alg;
2533 	char *sigtype = NULL;
2534 	int r;
2535 
2536 	if (requested_alg == NULL)
2537 		return 0;
2538 	if ((expected_alg = sshkey_sigalg_by_name(requested_alg)) == NULL)
2539 		return SSH_ERR_INVALID_ARGUMENT;
2540 	if ((r = get_sigtype(sig, siglen, &sigtype)) != 0)
2541 		return r;
2542 	r = strcmp(expected_alg, sigtype) == 0;
2543 	free(sigtype);
2544 	return r ? 0 : SSH_ERR_SIGN_ALG_UNSUPPORTED;
2545 }
2546 
2547 int
2548 sshkey_sign(struct sshkey *key,
2549     u_char **sigp, size_t *lenp,
2550     const u_char *data, size_t datalen, const char *alg, u_int compat)
2551 {
2552 	int was_shielded = sshkey_is_shielded(key);
2553 	int r2, r = SSH_ERR_INTERNAL_ERROR;
2554 
2555 	if (sigp != NULL)
2556 		*sigp = NULL;
2557 	if (lenp != NULL)
2558 		*lenp = 0;
2559 	if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2560 		return SSH_ERR_INVALID_ARGUMENT;
2561 	if ((r = sshkey_unshield_private(key)) != 0)
2562 		return r;
2563 	switch (key->type) {
2564 #ifdef WITH_OPENSSL
2565 	case KEY_DSA_CERT:
2566 	case KEY_DSA:
2567 		r = ssh_dss_sign(key, sigp, lenp, data, datalen, compat);
2568 		break;
2569 	case KEY_ECDSA_CERT:
2570 	case KEY_ECDSA:
2571 		r = ssh_ecdsa_sign(key, sigp, lenp, data, datalen, compat);
2572 		break;
2573 	case KEY_RSA_CERT:
2574 	case KEY_RSA:
2575 		r = ssh_rsa_sign(key, sigp, lenp, data, datalen, alg);
2576 		break;
2577 #endif /* WITH_OPENSSL */
2578 	case KEY_ED25519:
2579 	case KEY_ED25519_CERT:
2580 		r = ssh_ed25519_sign(key, sigp, lenp, data, datalen, compat);
2581 		break;
2582 #ifdef WITH_XMSS
2583 	case KEY_XMSS:
2584 	case KEY_XMSS_CERT:
2585 		r = ssh_xmss_sign(key, sigp, lenp, data, datalen, compat);
2586 		break;
2587 #endif /* WITH_XMSS */
2588 	default:
2589 		r = SSH_ERR_KEY_TYPE_UNKNOWN;
2590 		break;
2591 	}
2592 	if (was_shielded && (r2 = sshkey_shield_private(key)) != 0)
2593 		return r2;
2594 	return r;
2595 }
2596 
2597 /*
2598  * ssh_key_verify returns 0 for a correct signature  and < 0 on error.
2599  * If "alg" specified, then the signature must use that algorithm.
2600  */
2601 int
2602 sshkey_verify(const struct sshkey *key,
2603     const u_char *sig, size_t siglen,
2604     const u_char *data, size_t dlen, const char *alg, u_int compat)
2605 {
2606 	if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2607 		return SSH_ERR_INVALID_ARGUMENT;
2608 	switch (key->type) {
2609 #ifdef WITH_OPENSSL
2610 	case KEY_DSA_CERT:
2611 	case KEY_DSA:
2612 		return ssh_dss_verify(key, sig, siglen, data, dlen, compat);
2613 	case KEY_ECDSA_CERT:
2614 	case KEY_ECDSA:
2615 		return ssh_ecdsa_verify(key, sig, siglen, data, dlen, compat);
2616 	case KEY_RSA_CERT:
2617 	case KEY_RSA:
2618 		return ssh_rsa_verify(key, sig, siglen, data, dlen, alg);
2619 #endif /* WITH_OPENSSL */
2620 	case KEY_ED25519:
2621 	case KEY_ED25519_CERT:
2622 		return ssh_ed25519_verify(key, sig, siglen, data, dlen, compat);
2623 #ifdef WITH_XMSS
2624 	case KEY_XMSS:
2625 	case KEY_XMSS_CERT:
2626 		return ssh_xmss_verify(key, sig, siglen, data, dlen, compat);
2627 #endif /* WITH_XMSS */
2628 	default:
2629 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2630 	}
2631 }
2632 
2633 /* Convert a plain key to their _CERT equivalent */
2634 int
2635 sshkey_to_certified(struct sshkey *k)
2636 {
2637 	int newtype;
2638 
2639 	switch (k->type) {
2640 #ifdef WITH_OPENSSL
2641 	case KEY_RSA:
2642 		newtype = KEY_RSA_CERT;
2643 		break;
2644 	case KEY_DSA:
2645 		newtype = KEY_DSA_CERT;
2646 		break;
2647 	case KEY_ECDSA:
2648 		newtype = KEY_ECDSA_CERT;
2649 		break;
2650 #endif /* WITH_OPENSSL */
2651 	case KEY_ED25519:
2652 		newtype = KEY_ED25519_CERT;
2653 		break;
2654 #ifdef WITH_XMSS
2655 	case KEY_XMSS:
2656 		newtype = KEY_XMSS_CERT;
2657 		break;
2658 #endif /* WITH_XMSS */
2659 	default:
2660 		return SSH_ERR_INVALID_ARGUMENT;
2661 	}
2662 	if ((k->cert = cert_new()) == NULL)
2663 		return SSH_ERR_ALLOC_FAIL;
2664 	k->type = newtype;
2665 	return 0;
2666 }
2667 
2668 /* Convert a certificate to its raw key equivalent */
2669 int
2670 sshkey_drop_cert(struct sshkey *k)
2671 {
2672 	if (!sshkey_type_is_cert(k->type))
2673 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2674 	cert_free(k->cert);
2675 	k->cert = NULL;
2676 	k->type = sshkey_type_plain(k->type);
2677 	return 0;
2678 }
2679 
2680 /* Sign a certified key, (re-)generating the signed certblob. */
2681 int
2682 sshkey_certify_custom(struct sshkey *k, struct sshkey *ca, const char *alg,
2683     sshkey_certify_signer *signer, void *signer_ctx)
2684 {
2685 	struct sshbuf *principals = NULL;
2686 	u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32];
2687 	size_t i, ca_len, sig_len;
2688 	int ret = SSH_ERR_INTERNAL_ERROR;
2689 	struct sshbuf *cert = NULL;
2690 	char *sigtype = NULL;
2691 #ifdef WITH_OPENSSL
2692 	const BIGNUM *rsa_n, *rsa_e, *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key;
2693 #endif /* WITH_OPENSSL */
2694 
2695 	if (k == NULL || k->cert == NULL ||
2696 	    k->cert->certblob == NULL || ca == NULL)
2697 		return SSH_ERR_INVALID_ARGUMENT;
2698 	if (!sshkey_is_cert(k))
2699 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2700 	if (!sshkey_type_is_valid_ca(ca->type))
2701 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2702 
2703 	/*
2704 	 * If no alg specified as argument but a signature_type was set,
2705 	 * then prefer that. If both were specified, then they must match.
2706 	 */
2707 	if (alg == NULL)
2708 		alg = k->cert->signature_type;
2709 	else if (k->cert->signature_type != NULL &&
2710 	    strcmp(alg, k->cert->signature_type) != 0)
2711 		return SSH_ERR_INVALID_ARGUMENT;
2712 
2713 	/*
2714 	 * If no signing algorithm or signature_type was specified and we're
2715 	 * using a RSA key, then default to a good signature algorithm.
2716 	 */
2717 	if (alg == NULL && ca->type == KEY_RSA)
2718 		alg = "rsa-sha2-512";
2719 
2720 	if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0)
2721 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2722 
2723 	cert = k->cert->certblob; /* for readability */
2724 	sshbuf_reset(cert);
2725 	if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0)
2726 		goto out;
2727 
2728 	/* -v01 certs put nonce first */
2729 	arc4random_buf(&nonce, sizeof(nonce));
2730 	if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0)
2731 		goto out;
2732 
2733 	/* XXX this substantially duplicates to_blob(); refactor */
2734 	switch (k->type) {
2735 #ifdef WITH_OPENSSL
2736 	case KEY_DSA_CERT:
2737 		DSA_get0_pqg(k->dsa, &dsa_p, &dsa_q, &dsa_g);
2738 		DSA_get0_key(k->dsa, &dsa_pub_key, NULL);
2739 		if ((ret = sshbuf_put_bignum2(cert, dsa_p)) != 0 ||
2740 		    (ret = sshbuf_put_bignum2(cert, dsa_q)) != 0 ||
2741 		    (ret = sshbuf_put_bignum2(cert, dsa_g)) != 0 ||
2742 		    (ret = sshbuf_put_bignum2(cert, dsa_pub_key)) != 0)
2743 			goto out;
2744 		break;
2745 	case KEY_ECDSA_CERT:
2746 		if ((ret = sshbuf_put_cstring(cert,
2747 		    sshkey_curve_nid_to_name(k->ecdsa_nid))) != 0 ||
2748 		    (ret = sshbuf_put_ec(cert,
2749 		    EC_KEY_get0_public_key(k->ecdsa),
2750 		    EC_KEY_get0_group(k->ecdsa))) != 0)
2751 			goto out;
2752 		break;
2753 	case KEY_RSA_CERT:
2754 		RSA_get0_key(k->rsa, &rsa_n, &rsa_e, NULL);
2755 		if ((ret = sshbuf_put_bignum2(cert, rsa_e)) != 0 ||
2756 		    (ret = sshbuf_put_bignum2(cert, rsa_n)) != 0)
2757 			goto out;
2758 		break;
2759 #endif /* WITH_OPENSSL */
2760 	case KEY_ED25519_CERT:
2761 		if ((ret = sshbuf_put_string(cert,
2762 		    k->ed25519_pk, ED25519_PK_SZ)) != 0)
2763 			goto out;
2764 		break;
2765 #ifdef WITH_XMSS
2766 	case KEY_XMSS_CERT:
2767 		if (k->xmss_name == NULL) {
2768 			ret = SSH_ERR_INVALID_ARGUMENT;
2769 			goto out;
2770 		}
2771 		if ((ret = sshbuf_put_cstring(cert, k->xmss_name)) ||
2772 		    (ret = sshbuf_put_string(cert,
2773 		    k->xmss_pk, sshkey_xmss_pklen(k))) != 0)
2774 			goto out;
2775 		break;
2776 #endif /* WITH_XMSS */
2777 	default:
2778 		ret = SSH_ERR_INVALID_ARGUMENT;
2779 		goto out;
2780 	}
2781 
2782 	if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 ||
2783 	    (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 ||
2784 	    (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0)
2785 		goto out;
2786 
2787 	if ((principals = sshbuf_new()) == NULL) {
2788 		ret = SSH_ERR_ALLOC_FAIL;
2789 		goto out;
2790 	}
2791 	for (i = 0; i < k->cert->nprincipals; i++) {
2792 		if ((ret = sshbuf_put_cstring(principals,
2793 		    k->cert->principals[i])) != 0)
2794 			goto out;
2795 	}
2796 	if ((ret = sshbuf_put_stringb(cert, principals)) != 0 ||
2797 	    (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 ||
2798 	    (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 ||
2799 	    (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 ||
2800 	    (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 ||
2801 	    (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */
2802 	    (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0)
2803 		goto out;
2804 
2805 	/* Sign the whole mess */
2806 	if ((ret = signer(ca, &sig_blob, &sig_len, sshbuf_ptr(cert),
2807 	    sshbuf_len(cert), alg, 0, signer_ctx)) != 0)
2808 		goto out;
2809 	/* Check and update signature_type against what was actually used */
2810 	if ((ret = get_sigtype(sig_blob, sig_len, &sigtype)) != 0)
2811 		goto out;
2812 	if (alg != NULL && strcmp(alg, sigtype) != 0) {
2813 		ret = SSH_ERR_SIGN_ALG_UNSUPPORTED;
2814 		goto out;
2815 	}
2816 	if (k->cert->signature_type == NULL) {
2817 		k->cert->signature_type = sigtype;
2818 		sigtype = NULL;
2819 	}
2820 	/* Append signature and we are done */
2821 	if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0)
2822 		goto out;
2823 	ret = 0;
2824  out:
2825 	if (ret != 0)
2826 		sshbuf_reset(cert);
2827 	free(sig_blob);
2828 	free(ca_blob);
2829 	free(sigtype);
2830 	sshbuf_free(principals);
2831 	return ret;
2832 }
2833 
2834 static int
2835 default_key_sign(struct sshkey *key, u_char **sigp, size_t *lenp,
2836     const u_char *data, size_t datalen,
2837     const char *alg, u_int compat, void *ctx)
2838 {
2839 	if (ctx != NULL)
2840 		return SSH_ERR_INVALID_ARGUMENT;
2841 	return sshkey_sign(key, sigp, lenp, data, datalen, alg, compat);
2842 }
2843 
2844 int
2845 sshkey_certify(struct sshkey *k, struct sshkey *ca, const char *alg)
2846 {
2847 	return sshkey_certify_custom(k, ca, alg, default_key_sign, NULL);
2848 }
2849 
2850 int
2851 sshkey_cert_check_authority(const struct sshkey *k,
2852     int want_host, int require_principal,
2853     const char *name, const char **reason)
2854 {
2855 	u_int i, principal_matches;
2856 	time_t now = time(NULL);
2857 
2858 	if (reason != NULL)
2859 		*reason = NULL;
2860 
2861 	if (want_host) {
2862 		if (k->cert->type != SSH2_CERT_TYPE_HOST) {
2863 			*reason = "Certificate invalid: not a host certificate";
2864 			return SSH_ERR_KEY_CERT_INVALID;
2865 		}
2866 	} else {
2867 		if (k->cert->type != SSH2_CERT_TYPE_USER) {
2868 			*reason = "Certificate invalid: not a user certificate";
2869 			return SSH_ERR_KEY_CERT_INVALID;
2870 		}
2871 	}
2872 	if (now < 0) {
2873 		/* yikes - system clock before epoch! */
2874 		*reason = "Certificate invalid: not yet valid";
2875 		return SSH_ERR_KEY_CERT_INVALID;
2876 	}
2877 	if ((u_int64_t)now < k->cert->valid_after) {
2878 		*reason = "Certificate invalid: not yet valid";
2879 		return SSH_ERR_KEY_CERT_INVALID;
2880 	}
2881 	if ((u_int64_t)now >= k->cert->valid_before) {
2882 		*reason = "Certificate invalid: expired";
2883 		return SSH_ERR_KEY_CERT_INVALID;
2884 	}
2885 	if (k->cert->nprincipals == 0) {
2886 		if (require_principal) {
2887 			*reason = "Certificate lacks principal list";
2888 			return SSH_ERR_KEY_CERT_INVALID;
2889 		}
2890 	} else if (name != NULL) {
2891 		principal_matches = 0;
2892 		for (i = 0; i < k->cert->nprincipals; i++) {
2893 			if (strcmp(name, k->cert->principals[i]) == 0) {
2894 				principal_matches = 1;
2895 				break;
2896 			}
2897 		}
2898 		if (!principal_matches) {
2899 			*reason = "Certificate invalid: name is not a listed "
2900 			    "principal";
2901 			return SSH_ERR_KEY_CERT_INVALID;
2902 		}
2903 	}
2904 	return 0;
2905 }
2906 
2907 size_t
2908 sshkey_format_cert_validity(const struct sshkey_cert *cert, char *s, size_t l)
2909 {
2910 	char from[32], to[32], ret[64];
2911 	time_t tt;
2912 	struct tm *tm;
2913 
2914 	*from = *to = '\0';
2915 	if (cert->valid_after == 0 &&
2916 	    cert->valid_before == 0xffffffffffffffffULL)
2917 		return strlcpy(s, "forever", l);
2918 
2919 	if (cert->valid_after != 0) {
2920 		/* XXX revisit INT_MAX in 2038 :) */
2921 		tt = cert->valid_after > INT_MAX ?
2922 		    INT_MAX : cert->valid_after;
2923 		tm = localtime(&tt);
2924 		strftime(from, sizeof(from), "%Y-%m-%dT%H:%M:%S", tm);
2925 	}
2926 	if (cert->valid_before != 0xffffffffffffffffULL) {
2927 		/* XXX revisit INT_MAX in 2038 :) */
2928 		tt = cert->valid_before > INT_MAX ?
2929 		    INT_MAX : cert->valid_before;
2930 		tm = localtime(&tt);
2931 		strftime(to, sizeof(to), "%Y-%m-%dT%H:%M:%S", tm);
2932 	}
2933 
2934 	if (cert->valid_after == 0)
2935 		snprintf(ret, sizeof(ret), "before %s", to);
2936 	else if (cert->valid_before == 0xffffffffffffffffULL)
2937 		snprintf(ret, sizeof(ret), "after %s", from);
2938 	else
2939 		snprintf(ret, sizeof(ret), "from %s to %s", from, to);
2940 
2941 	return strlcpy(s, ret, l);
2942 }
2943 
2944 int
2945 sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
2946     enum sshkey_serialize_rep opts)
2947 {
2948 	int r = SSH_ERR_INTERNAL_ERROR;
2949 	int was_shielded = sshkey_is_shielded(key);
2950 	struct sshbuf *b = NULL;
2951 #ifdef WITH_OPENSSL
2952 	const BIGNUM *rsa_n, *rsa_e, *rsa_d, *rsa_iqmp, *rsa_p, *rsa_q;
2953 	const BIGNUM *dsa_p, *dsa_q, *dsa_g, *dsa_pub_key, *dsa_priv_key;
2954 #endif /* WITH_OPENSSL */
2955 
2956 	if ((r = sshkey_unshield_private(key)) != 0)
2957 		return r;
2958 	if ((b = sshbuf_new()) == NULL)
2959 		return SSH_ERR_ALLOC_FAIL;
2960 	if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0)
2961 		goto out;
2962 	switch (key->type) {
2963 #ifdef WITH_OPENSSL
2964 	case KEY_RSA:
2965 		RSA_get0_key(key->rsa, &rsa_n, &rsa_e, &rsa_d);
2966 		RSA_get0_factors(key->rsa, &rsa_p, &rsa_q);
2967 		RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp);
2968 		if ((r = sshbuf_put_bignum2(b, rsa_n)) != 0 ||
2969 		    (r = sshbuf_put_bignum2(b, rsa_e)) != 0 ||
2970 		    (r = sshbuf_put_bignum2(b, rsa_d)) != 0 ||
2971 		    (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 ||
2972 		    (r = sshbuf_put_bignum2(b, rsa_p)) != 0 ||
2973 		    (r = sshbuf_put_bignum2(b, rsa_q)) != 0)
2974 			goto out;
2975 		break;
2976 	case KEY_RSA_CERT:
2977 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2978 			r = SSH_ERR_INVALID_ARGUMENT;
2979 			goto out;
2980 		}
2981 		RSA_get0_key(key->rsa, NULL, NULL, &rsa_d);
2982 		RSA_get0_factors(key->rsa, &rsa_p, &rsa_q);
2983 		RSA_get0_crt_params(key->rsa, NULL, NULL, &rsa_iqmp);
2984 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2985 		    (r = sshbuf_put_bignum2(b, rsa_d)) != 0 ||
2986 		    (r = sshbuf_put_bignum2(b, rsa_iqmp)) != 0 ||
2987 		    (r = sshbuf_put_bignum2(b, rsa_p)) != 0 ||
2988 		    (r = sshbuf_put_bignum2(b, rsa_q)) != 0)
2989 			goto out;
2990 		break;
2991 	case KEY_DSA:
2992 		DSA_get0_pqg(key->dsa, &dsa_p, &dsa_q, &dsa_g);
2993 		DSA_get0_key(key->dsa, &dsa_pub_key, &dsa_priv_key);
2994 		if ((r = sshbuf_put_bignum2(b, dsa_p)) != 0 ||
2995 		    (r = sshbuf_put_bignum2(b, dsa_q)) != 0 ||
2996 		    (r = sshbuf_put_bignum2(b, dsa_g)) != 0 ||
2997 		    (r = sshbuf_put_bignum2(b, dsa_pub_key)) != 0 ||
2998 		    (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0)
2999 			goto out;
3000 		break;
3001 	case KEY_DSA_CERT:
3002 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
3003 			r = SSH_ERR_INVALID_ARGUMENT;
3004 			goto out;
3005 		}
3006 		DSA_get0_key(key->dsa, NULL, &dsa_priv_key);
3007 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
3008 		    (r = sshbuf_put_bignum2(b, dsa_priv_key)) != 0)
3009 			goto out;
3010 		break;
3011 	case KEY_ECDSA:
3012 		if ((r = sshbuf_put_cstring(b,
3013 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
3014 		    (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 ||
3015 		    (r = sshbuf_put_bignum2(b,
3016 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
3017 			goto out;
3018 		break;
3019 	case KEY_ECDSA_CERT:
3020 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
3021 			r = SSH_ERR_INVALID_ARGUMENT;
3022 			goto out;
3023 		}
3024 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
3025 		    (r = sshbuf_put_bignum2(b,
3026 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
3027 			goto out;
3028 		break;
3029 #endif /* WITH_OPENSSL */
3030 	case KEY_ED25519:
3031 		if ((r = sshbuf_put_string(b, key->ed25519_pk,
3032 		    ED25519_PK_SZ)) != 0 ||
3033 		    (r = sshbuf_put_string(b, key->ed25519_sk,
3034 		    ED25519_SK_SZ)) != 0)
3035 			goto out;
3036 		break;
3037 	case KEY_ED25519_CERT:
3038 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
3039 			r = SSH_ERR_INVALID_ARGUMENT;
3040 			goto out;
3041 		}
3042 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
3043 		    (r = sshbuf_put_string(b, key->ed25519_pk,
3044 		    ED25519_PK_SZ)) != 0 ||
3045 		    (r = sshbuf_put_string(b, key->ed25519_sk,
3046 		    ED25519_SK_SZ)) != 0)
3047 			goto out;
3048 		break;
3049 #ifdef WITH_XMSS
3050 	case KEY_XMSS:
3051 		if (key->xmss_name == NULL) {
3052 			r = SSH_ERR_INVALID_ARGUMENT;
3053 			goto out;
3054 		}
3055 		if ((r = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
3056 		    (r = sshbuf_put_string(b, key->xmss_pk,
3057 		    sshkey_xmss_pklen(key))) != 0 ||
3058 		    (r = sshbuf_put_string(b, key->xmss_sk,
3059 		    sshkey_xmss_sklen(key))) != 0 ||
3060 		    (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0)
3061 			goto out;
3062 		break;
3063 	case KEY_XMSS_CERT:
3064 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0 ||
3065 		    key->xmss_name == NULL) {
3066 			r = SSH_ERR_INVALID_ARGUMENT;
3067 			goto out;
3068 		}
3069 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
3070 		    (r = sshbuf_put_cstring(b, key->xmss_name)) != 0 ||
3071 		    (r = sshbuf_put_string(b, key->xmss_pk,
3072 		    sshkey_xmss_pklen(key))) != 0 ||
3073 		    (r = sshbuf_put_string(b, key->xmss_sk,
3074 		    sshkey_xmss_sklen(key))) != 0 ||
3075 		    (r = sshkey_xmss_serialize_state_opt(key, b, opts)) != 0)
3076 			goto out;
3077 		break;
3078 #endif /* WITH_XMSS */
3079 	default:
3080 		r = SSH_ERR_INVALID_ARGUMENT;
3081 		goto out;
3082 	}
3083 	/*
3084 	 * success (but we still need to append the output to buf after
3085 	 * possibly re-shielding the private key)
3086 	 */
3087 	r = 0;
3088  out:
3089 	if (was_shielded)
3090 		r = sshkey_shield_private(key);
3091 	if (r == 0)
3092 		r = sshbuf_putb(buf, b);
3093 	sshbuf_free(b);
3094 
3095 	return r;
3096 }
3097 
3098 int
3099 sshkey_private_serialize(struct sshkey *key, struct sshbuf *b)
3100 {
3101 	return sshkey_private_serialize_opt(key, b,
3102 	    SSHKEY_SERIALIZE_DEFAULT);
3103 }
3104 
3105 int
3106 sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
3107 {
3108 	char *tname = NULL, *curve = NULL, *xmss_name = NULL;
3109 	struct sshkey *k = NULL;
3110 	size_t pklen = 0, sklen = 0;
3111 	int type, r = SSH_ERR_INTERNAL_ERROR;
3112 	u_char *ed25519_pk = NULL, *ed25519_sk = NULL;
3113 	u_char *xmss_pk = NULL, *xmss_sk = NULL;
3114 #ifdef WITH_OPENSSL
3115 	BIGNUM *exponent = NULL;
3116 	BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL;
3117 	BIGNUM *rsa_iqmp = NULL, *rsa_p = NULL, *rsa_q = NULL;
3118 	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL;
3119 	BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL;
3120 #endif /* WITH_OPENSSL */
3121 
3122 	if (kp != NULL)
3123 		*kp = NULL;
3124 	if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0)
3125 		goto out;
3126 	type = sshkey_type_from_name(tname);
3127 	switch (type) {
3128 #ifdef WITH_OPENSSL
3129 	case KEY_DSA:
3130 		if ((k = sshkey_new(type)) == NULL) {
3131 			r = SSH_ERR_ALLOC_FAIL;
3132 			goto out;
3133 		}
3134 		if ((r = sshbuf_get_bignum2(buf, &dsa_p)) != 0 ||
3135 		    (r = sshbuf_get_bignum2(buf, &dsa_q)) != 0 ||
3136 		    (r = sshbuf_get_bignum2(buf, &dsa_g)) != 0 ||
3137 		    (r = sshbuf_get_bignum2(buf, &dsa_pub_key)) != 0 ||
3138 		    (r = sshbuf_get_bignum2(buf, &dsa_priv_key)) != 0)
3139 			goto out;
3140 		if (!DSA_set0_pqg(k->dsa, dsa_p, dsa_q, dsa_g)) {
3141 			r = SSH_ERR_LIBCRYPTO_ERROR;
3142 			goto out;
3143 		}
3144 		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
3145 		if (!DSA_set0_key(k->dsa, dsa_pub_key, dsa_priv_key)) {
3146 			r = SSH_ERR_LIBCRYPTO_ERROR;
3147 			goto out;
3148 		}
3149 		dsa_pub_key = dsa_priv_key = NULL; /* transferred */
3150 		break;
3151 	case KEY_DSA_CERT:
3152 		if ((r = sshkey_froms(buf, &k)) != 0 ||
3153 		    (r = sshbuf_get_bignum2(buf, &dsa_priv_key)) != 0)
3154 			goto out;
3155 		if (!DSA_set0_key(k->dsa, NULL, dsa_priv_key)) {
3156 			r = SSH_ERR_LIBCRYPTO_ERROR;
3157 			goto out;
3158 		}
3159 		dsa_priv_key = NULL; /* transferred */
3160 		break;
3161 	case KEY_ECDSA:
3162 		if ((k = sshkey_new(type)) == NULL) {
3163 			r = SSH_ERR_ALLOC_FAIL;
3164 			goto out;
3165 		}
3166 		if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) {
3167 			r = SSH_ERR_INVALID_ARGUMENT;
3168 			goto out;
3169 		}
3170 		if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0)
3171 			goto out;
3172 		if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
3173 			r = SSH_ERR_EC_CURVE_MISMATCH;
3174 			goto out;
3175 		}
3176 		k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
3177 		if (k->ecdsa  == NULL) {
3178 			r = SSH_ERR_LIBCRYPTO_ERROR;
3179 			goto out;
3180 		}
3181 		if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0 ||
3182 		    (r = sshbuf_get_bignum2(buf, &exponent)))
3183 			goto out;
3184 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
3185 			r = SSH_ERR_LIBCRYPTO_ERROR;
3186 			goto out;
3187 		}
3188 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
3189 		    EC_KEY_get0_public_key(k->ecdsa))) != 0 ||
3190 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
3191 			goto out;
3192 		break;
3193 	case KEY_ECDSA_CERT:
3194 		if ((r = sshkey_froms(buf, &k)) != 0 ||
3195 		    (r = sshbuf_get_bignum2(buf, &exponent)) != 0)
3196 			goto out;
3197 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
3198 			r = SSH_ERR_LIBCRYPTO_ERROR;
3199 			goto out;
3200 		}
3201 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
3202 		    EC_KEY_get0_public_key(k->ecdsa))) != 0 ||
3203 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
3204 			goto out;
3205 		break;
3206 	case KEY_RSA:
3207 		if ((k = sshkey_new(type)) == NULL) {
3208 			r = SSH_ERR_ALLOC_FAIL;
3209 			goto out;
3210 		}
3211 		if ((r = sshbuf_get_bignum2(buf, &rsa_n)) != 0 ||
3212 		    (r = sshbuf_get_bignum2(buf, &rsa_e)) != 0 ||
3213 		    (r = sshbuf_get_bignum2(buf, &rsa_d)) != 0 ||
3214 		    (r = sshbuf_get_bignum2(buf, &rsa_iqmp)) != 0 ||
3215 		    (r = sshbuf_get_bignum2(buf, &rsa_p)) != 0 ||
3216 		    (r = sshbuf_get_bignum2(buf, &rsa_q)) != 0)
3217 			goto out;
3218 		if (!RSA_set0_key(k->rsa, rsa_n, rsa_e, rsa_d)) {
3219 			r = SSH_ERR_LIBCRYPTO_ERROR;
3220 			goto out;
3221 		}
3222 		rsa_n = rsa_e = rsa_d = NULL; /* transferred */
3223 		if (!RSA_set0_factors(k->rsa, rsa_p, rsa_q)) {
3224 			r = SSH_ERR_LIBCRYPTO_ERROR;
3225 			goto out;
3226 		}
3227 		rsa_p = rsa_q = NULL; /* transferred */
3228 		if ((r = check_rsa_length(k->rsa)) != 0)
3229 			goto out;
3230 		if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0)
3231 			goto out;
3232 		break;
3233 	case KEY_RSA_CERT:
3234 		if ((r = sshkey_froms(buf, &k)) != 0 ||
3235 		    (r = sshbuf_get_bignum2(buf, &rsa_d)) != 0 ||
3236 		    (r = sshbuf_get_bignum2(buf, &rsa_iqmp)) != 0 ||
3237 		    (r = sshbuf_get_bignum2(buf, &rsa_p)) != 0 ||
3238 		    (r = sshbuf_get_bignum2(buf, &rsa_q)) != 0)
3239 			goto out;
3240 		if (!RSA_set0_key(k->rsa, NULL, NULL, rsa_d)) {
3241 			r = SSH_ERR_LIBCRYPTO_ERROR;
3242 			goto out;
3243 		}
3244 		rsa_d = NULL; /* transferred */
3245 		if (!RSA_set0_factors(k->rsa, rsa_p, rsa_q)) {
3246 			r = SSH_ERR_LIBCRYPTO_ERROR;
3247 			goto out;
3248 		}
3249 		rsa_p = rsa_q = NULL; /* transferred */
3250 		if ((r = check_rsa_length(k->rsa)) != 0)
3251 			goto out;
3252 		if ((r = ssh_rsa_complete_crt_parameters(k, rsa_iqmp)) != 0)
3253 			goto out;
3254 		break;
3255 #endif /* WITH_OPENSSL */
3256 	case KEY_ED25519:
3257 		if ((k = sshkey_new(type)) == NULL) {
3258 			r = SSH_ERR_ALLOC_FAIL;
3259 			goto out;
3260 		}
3261 		if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
3262 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
3263 			goto out;
3264 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
3265 			r = SSH_ERR_INVALID_FORMAT;
3266 			goto out;
3267 		}
3268 		k->ed25519_pk = ed25519_pk;
3269 		k->ed25519_sk = ed25519_sk;
3270 		ed25519_pk = ed25519_sk = NULL;
3271 		break;
3272 	case KEY_ED25519_CERT:
3273 		if ((r = sshkey_froms(buf, &k)) != 0 ||
3274 		    (r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
3275 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
3276 			goto out;
3277 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
3278 			r = SSH_ERR_INVALID_FORMAT;
3279 			goto out;
3280 		}
3281 		k->ed25519_pk = ed25519_pk;
3282 		k->ed25519_sk = ed25519_sk;
3283 		ed25519_pk = ed25519_sk = NULL;
3284 		break;
3285 #ifdef WITH_XMSS
3286 	case KEY_XMSS:
3287 		if ((k = sshkey_new(type)) == NULL) {
3288 			r = SSH_ERR_ALLOC_FAIL;
3289 			goto out;
3290 		}
3291 		if ((r = sshbuf_get_cstring(buf, &xmss_name, NULL)) != 0 ||
3292 		    (r = sshkey_xmss_init(k, xmss_name)) != 0 ||
3293 		    (r = sshbuf_get_string(buf, &xmss_pk, &pklen)) != 0 ||
3294 		    (r = sshbuf_get_string(buf, &xmss_sk, &sklen)) != 0)
3295 			goto out;
3296 		if (pklen != sshkey_xmss_pklen(k) ||
3297 		    sklen != sshkey_xmss_sklen(k)) {
3298 			r = SSH_ERR_INVALID_FORMAT;
3299 			goto out;
3300 		}
3301 		k->xmss_pk = xmss_pk;
3302 		k->xmss_sk = xmss_sk;
3303 		xmss_pk = xmss_sk = NULL;
3304 		/* optional internal state */
3305 		if ((r = sshkey_xmss_deserialize_state_opt(k, buf)) != 0)
3306 			goto out;
3307 		break;
3308 	case KEY_XMSS_CERT:
3309 		if ((r = sshkey_froms(buf, &k)) != 0 ||
3310 		    (r = sshbuf_get_cstring(buf, &xmss_name, NULL)) != 0 ||
3311 		    (r = sshbuf_get_string(buf, &xmss_pk, &pklen)) != 0 ||
3312 		    (r = sshbuf_get_string(buf, &xmss_sk, &sklen)) != 0)
3313 			goto out;
3314 		if (strcmp(xmss_name, k->xmss_name)) {
3315 			r = SSH_ERR_INVALID_FORMAT;
3316 			goto out;
3317 		}
3318 		if (pklen != sshkey_xmss_pklen(k) ||
3319 		    sklen != sshkey_xmss_sklen(k)) {
3320 			r = SSH_ERR_INVALID_FORMAT;
3321 			goto out;
3322 		}
3323 		k->xmss_pk = xmss_pk;
3324 		k->xmss_sk = xmss_sk;
3325 		xmss_pk = xmss_sk = NULL;
3326 		/* optional internal state */
3327 		if ((r = sshkey_xmss_deserialize_state_opt(k, buf)) != 0)
3328 			goto out;
3329 		break;
3330 #endif /* WITH_XMSS */
3331 	default:
3332 		r = SSH_ERR_KEY_TYPE_UNKNOWN;
3333 		goto out;
3334 	}
3335 #ifdef WITH_OPENSSL
3336 	/* enable blinding */
3337 	switch (k->type) {
3338 	case KEY_RSA:
3339 	case KEY_RSA_CERT:
3340 		if (RSA_blinding_on(k->rsa, NULL) != 1) {
3341 			r = SSH_ERR_LIBCRYPTO_ERROR;
3342 			goto out;
3343 		}
3344 		break;
3345 	}
3346 #endif /* WITH_OPENSSL */
3347 	/* success */
3348 	r = 0;
3349 	if (kp != NULL) {
3350 		*kp = k;
3351 		k = NULL;
3352 	}
3353  out:
3354 	free(tname);
3355 	free(curve);
3356 #ifdef WITH_OPENSSL
3357 	BN_clear_free(exponent);
3358 	BN_clear_free(dsa_p);
3359 	BN_clear_free(dsa_q);
3360 	BN_clear_free(dsa_g);
3361 	BN_clear_free(dsa_pub_key);
3362 	BN_clear_free(dsa_priv_key);
3363 	BN_clear_free(rsa_n);
3364 	BN_clear_free(rsa_e);
3365 	BN_clear_free(rsa_d);
3366 	BN_clear_free(rsa_p);
3367 	BN_clear_free(rsa_q);
3368 	BN_clear_free(rsa_iqmp);
3369 #endif /* WITH_OPENSSL */
3370 	sshkey_free(k);
3371 	freezero(ed25519_pk, pklen);
3372 	freezero(ed25519_sk, sklen);
3373 	free(xmss_name);
3374 	freezero(xmss_pk, pklen);
3375 	freezero(xmss_sk, sklen);
3376 	return r;
3377 }
3378 
3379 #ifdef WITH_OPENSSL
3380 int
3381 sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
3382 {
3383 	BN_CTX *bnctx;
3384 	EC_POINT *nq = NULL;
3385 	BIGNUM *order, *x, *y, *tmp;
3386 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
3387 
3388 	/*
3389 	 * NB. This assumes OpenSSL has already verified that the public
3390 	 * point lies on the curve. This is done by EC_POINT_oct2point()
3391 	 * implicitly calling EC_POINT_is_on_curve(). If this code is ever
3392 	 * reachable with public points not unmarshalled using
3393 	 * EC_POINT_oct2point then the caller will need to explicitly check.
3394 	 */
3395 
3396 	if ((bnctx = BN_CTX_new()) == NULL)
3397 		return SSH_ERR_ALLOC_FAIL;
3398 	BN_CTX_start(bnctx);
3399 
3400 	/*
3401 	 * We shouldn't ever hit this case because bignum_get_ecpoint()
3402 	 * refuses to load GF2m points.
3403 	 */
3404 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
3405 	    NID_X9_62_prime_field)
3406 		goto out;
3407 
3408 	/* Q != infinity */
3409 	if (EC_POINT_is_at_infinity(group, public))
3410 		goto out;
3411 
3412 	if ((x = BN_CTX_get(bnctx)) == NULL ||
3413 	    (y = BN_CTX_get(bnctx)) == NULL ||
3414 	    (order = BN_CTX_get(bnctx)) == NULL ||
3415 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
3416 		ret = SSH_ERR_ALLOC_FAIL;
3417 		goto out;
3418 	}
3419 
3420 	/* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
3421 	if (EC_GROUP_get_order(group, order, bnctx) != 1 ||
3422 	    EC_POINT_get_affine_coordinates_GFp(group, public,
3423 	    x, y, bnctx) != 1) {
3424 		ret = SSH_ERR_LIBCRYPTO_ERROR;
3425 		goto out;
3426 	}
3427 	if (BN_num_bits(x) <= BN_num_bits(order) / 2 ||
3428 	    BN_num_bits(y) <= BN_num_bits(order) / 2)
3429 		goto out;
3430 
3431 	/* nQ == infinity (n == order of subgroup) */
3432 	if ((nq = EC_POINT_new(group)) == NULL) {
3433 		ret = SSH_ERR_ALLOC_FAIL;
3434 		goto out;
3435 	}
3436 	if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1) {
3437 		ret = SSH_ERR_LIBCRYPTO_ERROR;
3438 		goto out;
3439 	}
3440 	if (EC_POINT_is_at_infinity(group, nq) != 1)
3441 		goto out;
3442 
3443 	/* x < order - 1, y < order - 1 */
3444 	if (!BN_sub(tmp, order, BN_value_one())) {
3445 		ret = SSH_ERR_LIBCRYPTO_ERROR;
3446 		goto out;
3447 	}
3448 	if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0)
3449 		goto out;
3450 	ret = 0;
3451  out:
3452 	BN_CTX_free(bnctx);
3453 	EC_POINT_free(nq);
3454 	return ret;
3455 }
3456 
3457 int
3458 sshkey_ec_validate_private(const EC_KEY *key)
3459 {
3460 	BN_CTX *bnctx;
3461 	BIGNUM *order, *tmp;
3462 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
3463 
3464 	if ((bnctx = BN_CTX_new()) == NULL)
3465 		return SSH_ERR_ALLOC_FAIL;
3466 	BN_CTX_start(bnctx);
3467 
3468 	if ((order = BN_CTX_get(bnctx)) == NULL ||
3469 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
3470 		ret = SSH_ERR_ALLOC_FAIL;
3471 		goto out;
3472 	}
3473 
3474 	/* log2(private) > log2(order)/2 */
3475 	if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1) {
3476 		ret = SSH_ERR_LIBCRYPTO_ERROR;
3477 		goto out;
3478 	}
3479 	if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
3480 	    BN_num_bits(order) / 2)
3481 		goto out;
3482 
3483 	/* private < order - 1 */
3484 	if (!BN_sub(tmp, order, BN_value_one())) {
3485 		ret = SSH_ERR_LIBCRYPTO_ERROR;
3486 		goto out;
3487 	}
3488 	if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0)
3489 		goto out;
3490 	ret = 0;
3491  out:
3492 	BN_CTX_free(bnctx);
3493 	return ret;
3494 }
3495 
3496 void
3497 sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
3498 {
3499 	BIGNUM *x, *y;
3500 	BN_CTX *bnctx;
3501 
3502 	if (point == NULL) {
3503 		fputs("point=(NULL)\n", stderr);
3504 		return;
3505 	}
3506 	if ((bnctx = BN_CTX_new()) == NULL) {
3507 		fprintf(stderr, "%s: BN_CTX_new failed\n", __func__);
3508 		return;
3509 	}
3510 	BN_CTX_start(bnctx);
3511 	if ((x = BN_CTX_get(bnctx)) == NULL ||
3512 	    (y = BN_CTX_get(bnctx)) == NULL) {
3513 		fprintf(stderr, "%s: BN_CTX_get failed\n", __func__);
3514 		return;
3515 	}
3516 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
3517 	    NID_X9_62_prime_field) {
3518 		fprintf(stderr, "%s: group is not a prime field\n", __func__);
3519 		return;
3520 	}
3521 	if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y,
3522 	    bnctx) != 1) {
3523 		fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n",
3524 		    __func__);
3525 		return;
3526 	}
3527 	fputs("x=", stderr);
3528 	BN_print_fp(stderr, x);
3529 	fputs("\ny=", stderr);
3530 	BN_print_fp(stderr, y);
3531 	fputs("\n", stderr);
3532 	BN_CTX_free(bnctx);
3533 }
3534 
3535 void
3536 sshkey_dump_ec_key(const EC_KEY *key)
3537 {
3538 	const BIGNUM *exponent;
3539 
3540 	sshkey_dump_ec_point(EC_KEY_get0_group(key),
3541 	    EC_KEY_get0_public_key(key));
3542 	fputs("exponent=", stderr);
3543 	if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
3544 		fputs("(NULL)", stderr);
3545 	else
3546 		BN_print_fp(stderr, EC_KEY_get0_private_key(key));
3547 	fputs("\n", stderr);
3548 }
3549 #endif /* WITH_OPENSSL */
3550 
3551 static int
3552 sshkey_private_to_blob2(struct sshkey *prv, struct sshbuf *blob,
3553     const char *passphrase, const char *comment, const char *ciphername,
3554     int rounds)
3555 {
3556 	u_char *cp, *key = NULL, *pubkeyblob = NULL;
3557 	u_char salt[SALT_LEN];
3558 	char *b64 = NULL;
3559 	size_t i, pubkeylen, keylen, ivlen, blocksize, authlen;
3560 	u_int check;
3561 	int r = SSH_ERR_INTERNAL_ERROR;
3562 	struct sshcipher_ctx *ciphercontext = NULL;
3563 	const struct sshcipher *cipher;
3564 	const char *kdfname = KDFNAME;
3565 	struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL;
3566 
3567 	if (rounds <= 0)
3568 		rounds = DEFAULT_ROUNDS;
3569 	if (passphrase == NULL || !strlen(passphrase)) {
3570 		ciphername = "none";
3571 		kdfname = "none";
3572 	} else if (ciphername == NULL)
3573 		ciphername = DEFAULT_CIPHERNAME;
3574 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
3575 		r = SSH_ERR_INVALID_ARGUMENT;
3576 		goto out;
3577 	}
3578 
3579 	if ((kdf = sshbuf_new()) == NULL ||
3580 	    (encoded = sshbuf_new()) == NULL ||
3581 	    (encrypted = sshbuf_new()) == NULL) {
3582 		r = SSH_ERR_ALLOC_FAIL;
3583 		goto out;
3584 	}
3585 	blocksize = cipher_blocksize(cipher);
3586 	keylen = cipher_keylen(cipher);
3587 	ivlen = cipher_ivlen(cipher);
3588 	authlen = cipher_authlen(cipher);
3589 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
3590 		r = SSH_ERR_ALLOC_FAIL;
3591 		goto out;
3592 	}
3593 	if (strcmp(kdfname, "bcrypt") == 0) {
3594 		arc4random_buf(salt, SALT_LEN);
3595 		if (bcrypt_pbkdf(passphrase, strlen(passphrase),
3596 		    salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) {
3597 			r = SSH_ERR_INVALID_ARGUMENT;
3598 			goto out;
3599 		}
3600 		if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 ||
3601 		    (r = sshbuf_put_u32(kdf, rounds)) != 0)
3602 			goto out;
3603 	} else if (strcmp(kdfname, "none") != 0) {
3604 		/* Unsupported KDF type */
3605 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3606 		goto out;
3607 	}
3608 	if ((r = cipher_init(&ciphercontext, cipher, key, keylen,
3609 	    key + keylen, ivlen, 1)) != 0)
3610 		goto out;
3611 
3612 	if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 ||
3613 	    (r = sshbuf_put_cstring(encoded, ciphername)) != 0 ||
3614 	    (r = sshbuf_put_cstring(encoded, kdfname)) != 0 ||
3615 	    (r = sshbuf_put_stringb(encoded, kdf)) != 0 ||
3616 	    (r = sshbuf_put_u32(encoded, 1)) != 0 ||	/* number of keys */
3617 	    (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 ||
3618 	    (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0)
3619 		goto out;
3620 
3621 	/* set up the buffer that will be encrypted */
3622 
3623 	/* Random check bytes */
3624 	check = arc4random();
3625 	if ((r = sshbuf_put_u32(encrypted, check)) != 0 ||
3626 	    (r = sshbuf_put_u32(encrypted, check)) != 0)
3627 		goto out;
3628 
3629 	/* append private key and comment*/
3630 	if ((r = sshkey_private_serialize_opt(prv, encrypted,
3631 	     SSHKEY_SERIALIZE_FULL)) != 0 ||
3632 	    (r = sshbuf_put_cstring(encrypted, comment)) != 0)
3633 		goto out;
3634 
3635 	/* padding */
3636 	i = 0;
3637 	while (sshbuf_len(encrypted) % blocksize) {
3638 		if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0)
3639 			goto out;
3640 	}
3641 
3642 	/* length in destination buffer */
3643 	if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0)
3644 		goto out;
3645 
3646 	/* encrypt */
3647 	if ((r = sshbuf_reserve(encoded,
3648 	    sshbuf_len(encrypted) + authlen, &cp)) != 0)
3649 		goto out;
3650 	if ((r = cipher_crypt(ciphercontext, 0, cp,
3651 	    sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0)
3652 		goto out;
3653 
3654 	/* uuencode */
3655 	if ((b64 = sshbuf_dtob64(encoded)) == NULL) {
3656 		r = SSH_ERR_ALLOC_FAIL;
3657 		goto out;
3658 	}
3659 
3660 	sshbuf_reset(blob);
3661 	if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0)
3662 		goto out;
3663 	for (i = 0; i < strlen(b64); i++) {
3664 		if ((r = sshbuf_put_u8(blob, b64[i])) != 0)
3665 			goto out;
3666 		/* insert line breaks */
3667 		if (i % 70 == 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3668 			goto out;
3669 	}
3670 	if (i % 70 != 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3671 		goto out;
3672 	if ((r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0)
3673 		goto out;
3674 
3675 	/* success */
3676 	r = 0;
3677 
3678  out:
3679 	sshbuf_free(kdf);
3680 	sshbuf_free(encoded);
3681 	sshbuf_free(encrypted);
3682 	cipher_free(ciphercontext);
3683 	explicit_bzero(salt, sizeof(salt));
3684 	if (key != NULL) {
3685 		explicit_bzero(key, keylen + ivlen);
3686 		free(key);
3687 	}
3688 	if (pubkeyblob != NULL) {
3689 		explicit_bzero(pubkeyblob, pubkeylen);
3690 		free(pubkeyblob);
3691 	}
3692 	if (b64 != NULL) {
3693 		explicit_bzero(b64, strlen(b64));
3694 		free(b64);
3695 	}
3696 	return r;
3697 }
3698 
3699 static int
3700 sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase,
3701     struct sshkey **keyp, char **commentp)
3702 {
3703 	char *comment = NULL, *ciphername = NULL, *kdfname = NULL;
3704 	const struct sshcipher *cipher = NULL;
3705 	const u_char *cp;
3706 	int r = SSH_ERR_INTERNAL_ERROR;
3707 	size_t encoded_len;
3708 	size_t i, keylen = 0, ivlen = 0, authlen = 0, slen = 0;
3709 	struct sshbuf *encoded = NULL, *decoded = NULL;
3710 	struct sshbuf *kdf = NULL, *decrypted = NULL;
3711 	struct sshcipher_ctx *ciphercontext = NULL;
3712 	struct sshkey *k = NULL;
3713 	u_char *key = NULL, *salt = NULL, *dp, pad, last;
3714 	u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
3715 
3716 	if (keyp != NULL)
3717 		*keyp = NULL;
3718 	if (commentp != NULL)
3719 		*commentp = NULL;
3720 
3721 	if ((encoded = sshbuf_new()) == NULL ||
3722 	    (decoded = sshbuf_new()) == NULL ||
3723 	    (decrypted = sshbuf_new()) == NULL) {
3724 		r = SSH_ERR_ALLOC_FAIL;
3725 		goto out;
3726 	}
3727 
3728 	/* check preamble */
3729 	cp = sshbuf_ptr(blob);
3730 	encoded_len = sshbuf_len(blob);
3731 	if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) ||
3732 	    memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) {
3733 		r = SSH_ERR_INVALID_FORMAT;
3734 		goto out;
3735 	}
3736 	cp += MARK_BEGIN_LEN;
3737 	encoded_len -= MARK_BEGIN_LEN;
3738 
3739 	/* Look for end marker, removing whitespace as we go */
3740 	while (encoded_len > 0) {
3741 		if (*cp != '\n' && *cp != '\r') {
3742 			if ((r = sshbuf_put_u8(encoded, *cp)) != 0)
3743 				goto out;
3744 		}
3745 		last = *cp;
3746 		encoded_len--;
3747 		cp++;
3748 		if (last == '\n') {
3749 			if (encoded_len >= MARK_END_LEN &&
3750 			    memcmp(cp, MARK_END, MARK_END_LEN) == 0) {
3751 				/* \0 terminate */
3752 				if ((r = sshbuf_put_u8(encoded, 0)) != 0)
3753 					goto out;
3754 				break;
3755 			}
3756 		}
3757 	}
3758 	if (encoded_len == 0) {
3759 		r = SSH_ERR_INVALID_FORMAT;
3760 		goto out;
3761 	}
3762 
3763 	/* decode base64 */
3764 	if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0)
3765 		goto out;
3766 
3767 	/* check magic */
3768 	if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) ||
3769 	    memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) {
3770 		r = SSH_ERR_INVALID_FORMAT;
3771 		goto out;
3772 	}
3773 	/* parse public portion of key */
3774 	if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
3775 	    (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 ||
3776 	    (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 ||
3777 	    (r = sshbuf_froms(decoded, &kdf)) != 0 ||
3778 	    (r = sshbuf_get_u32(decoded, &nkeys)) != 0 ||
3779 	    (r = sshbuf_skip_string(decoded)) != 0 || /* pubkey */
3780 	    (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0)
3781 		goto out;
3782 
3783 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
3784 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3785 		goto out;
3786 	}
3787 	if ((passphrase == NULL || strlen(passphrase) == 0) &&
3788 	    strcmp(ciphername, "none") != 0) {
3789 		/* passphrase required */
3790 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3791 		goto out;
3792 	}
3793 	if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) {
3794 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3795 		goto out;
3796 	}
3797 	if (!strcmp(kdfname, "none") && strcmp(ciphername, "none") != 0) {
3798 		r = SSH_ERR_INVALID_FORMAT;
3799 		goto out;
3800 	}
3801 	if (nkeys != 1) {
3802 		/* XXX only one key supported */
3803 		r = SSH_ERR_INVALID_FORMAT;
3804 		goto out;
3805 	}
3806 
3807 	/* check size of encrypted key blob */
3808 	blocksize = cipher_blocksize(cipher);
3809 	if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) {
3810 		r = SSH_ERR_INVALID_FORMAT;
3811 		goto out;
3812 	}
3813 
3814 	/* setup key */
3815 	keylen = cipher_keylen(cipher);
3816 	ivlen = cipher_ivlen(cipher);
3817 	authlen = cipher_authlen(cipher);
3818 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
3819 		r = SSH_ERR_ALLOC_FAIL;
3820 		goto out;
3821 	}
3822 	if (strcmp(kdfname, "bcrypt") == 0) {
3823 		if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
3824 		    (r = sshbuf_get_u32(kdf, &rounds)) != 0)
3825 			goto out;
3826 		if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
3827 		    key, keylen + ivlen, rounds) < 0) {
3828 			r = SSH_ERR_INVALID_FORMAT;
3829 			goto out;
3830 		}
3831 	}
3832 
3833 	/* check that an appropriate amount of auth data is present */
3834 	if (sshbuf_len(decoded) < encrypted_len + authlen) {
3835 		r = SSH_ERR_INVALID_FORMAT;
3836 		goto out;
3837 	}
3838 
3839 	/* decrypt private portion of key */
3840 	if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 ||
3841 	    (r = cipher_init(&ciphercontext, cipher, key, keylen,
3842 	    key + keylen, ivlen, 0)) != 0)
3843 		goto out;
3844 	if ((r = cipher_crypt(ciphercontext, 0, dp, sshbuf_ptr(decoded),
3845 	    encrypted_len, 0, authlen)) != 0) {
3846 		/* an integrity error here indicates an incorrect passphrase */
3847 		if (r == SSH_ERR_MAC_INVALID)
3848 			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3849 		goto out;
3850 	}
3851 	if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0)
3852 		goto out;
3853 	/* there should be no trailing data */
3854 	if (sshbuf_len(decoded) != 0) {
3855 		r = SSH_ERR_INVALID_FORMAT;
3856 		goto out;
3857 	}
3858 
3859 	/* check check bytes */
3860 	if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 ||
3861 	    (r = sshbuf_get_u32(decrypted, &check2)) != 0)
3862 		goto out;
3863 	if (check1 != check2) {
3864 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3865 		goto out;
3866 	}
3867 
3868 	/* Load the private key and comment */
3869 	if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 ||
3870 	    (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0)
3871 		goto out;
3872 
3873 	/* Check deterministic padding */
3874 	i = 0;
3875 	while (sshbuf_len(decrypted)) {
3876 		if ((r = sshbuf_get_u8(decrypted, &pad)) != 0)
3877 			goto out;
3878 		if (pad != (++i & 0xff)) {
3879 			r = SSH_ERR_INVALID_FORMAT;
3880 			goto out;
3881 		}
3882 	}
3883 
3884 	/* XXX decode pubkey and check against private */
3885 
3886 	/* success */
3887 	r = 0;
3888 	if (keyp != NULL) {
3889 		*keyp = k;
3890 		k = NULL;
3891 	}
3892 	if (commentp != NULL) {
3893 		*commentp = comment;
3894 		comment = NULL;
3895 	}
3896  out:
3897 	pad = 0;
3898 	cipher_free(ciphercontext);
3899 	free(ciphername);
3900 	free(kdfname);
3901 	free(comment);
3902 	if (salt != NULL) {
3903 		explicit_bzero(salt, slen);
3904 		free(salt);
3905 	}
3906 	if (key != NULL) {
3907 		explicit_bzero(key, keylen + ivlen);
3908 		free(key);
3909 	}
3910 	sshbuf_free(encoded);
3911 	sshbuf_free(decoded);
3912 	sshbuf_free(kdf);
3913 	sshbuf_free(decrypted);
3914 	sshkey_free(k);
3915 	return r;
3916 }
3917 
3918 
3919 #ifdef WITH_OPENSSL
3920 /* convert SSH v2 key in OpenSSL PEM format */
3921 static int
3922 sshkey_private_pem_to_blob(struct sshkey *key, struct sshbuf *buf,
3923     const char *_passphrase, const char *comment)
3924 {
3925 	int was_shielded = sshkey_is_shielded(key);
3926 	int success, r;
3927 	int blen, len = strlen(_passphrase);
3928 	u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
3929 	const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
3930 	char *bptr;
3931 	BIO *bio = NULL;
3932 	struct sshbuf *blob;
3933 
3934 	if (len > 0 && len <= 4)
3935 		return SSH_ERR_PASSPHRASE_TOO_SHORT;
3936 	if ((blob = sshbuf_new()) == NULL)
3937 		return SSH_ERR_ALLOC_FAIL;
3938 	if ((bio = BIO_new(BIO_s_mem())) == NULL) {
3939 		sshbuf_free(blob);
3940 		return SSH_ERR_ALLOC_FAIL;
3941 	}
3942 	if ((r = sshkey_unshield_private(key)) != 0)
3943 		goto out;
3944 
3945 	switch (key->type) {
3946 	case KEY_DSA:
3947 		success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
3948 		    cipher, passphrase, len, NULL, NULL);
3949 		break;
3950 	case KEY_ECDSA:
3951 		success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
3952 		    cipher, passphrase, len, NULL, NULL);
3953 		break;
3954 	case KEY_RSA:
3955 		success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
3956 		    cipher, passphrase, len, NULL, NULL);
3957 		break;
3958 	default:
3959 		success = 0;
3960 		break;
3961 	}
3962 	if (success == 0) {
3963 		r = SSH_ERR_LIBCRYPTO_ERROR;
3964 		goto out;
3965 	}
3966 	if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) {
3967 		r = SSH_ERR_INTERNAL_ERROR;
3968 		goto out;
3969 	}
3970 	if ((r = sshbuf_put(blob, bptr, blen)) != 0)
3971 		goto out;
3972 	r = 0;
3973  out:
3974 	if (was_shielded)
3975 		r = sshkey_shield_private(key);
3976 	if (r == 0)
3977 		r = sshbuf_putb(buf, blob);
3978 	sshbuf_free(blob);
3979 
3980 	BIO_free(bio);
3981 	return r;
3982 }
3983 #endif /* WITH_OPENSSL */
3984 
3985 /* Serialise "key" to buffer "blob" */
3986 int
3987 sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
3988     const char *passphrase, const char *comment,
3989     int force_new_format, const char *new_format_cipher, int new_format_rounds)
3990 {
3991 	switch (key->type) {
3992 #ifdef WITH_OPENSSL
3993 	case KEY_DSA:
3994 	case KEY_ECDSA:
3995 	case KEY_RSA:
3996 		if (force_new_format) {
3997 			return sshkey_private_to_blob2(key, blob, passphrase,
3998 			    comment, new_format_cipher, new_format_rounds);
3999 		}
4000 		return sshkey_private_pem_to_blob(key, blob,
4001 		    passphrase, comment);
4002 #endif /* WITH_OPENSSL */
4003 	case KEY_ED25519:
4004 #ifdef WITH_XMSS
4005 	case KEY_XMSS:
4006 #endif /* WITH_XMSS */
4007 		return sshkey_private_to_blob2(key, blob, passphrase,
4008 		    comment, new_format_cipher, new_format_rounds);
4009 	default:
4010 		return SSH_ERR_KEY_TYPE_UNKNOWN;
4011 	}
4012 }
4013 
4014 
4015 #ifdef WITH_OPENSSL
4016 static int
4017 translate_libcrypto_error(unsigned long pem_err)
4018 {
4019 	int pem_reason = ERR_GET_REASON(pem_err);
4020 
4021 	switch (ERR_GET_LIB(pem_err)) {
4022 	case ERR_LIB_PEM:
4023 		switch (pem_reason) {
4024 		case PEM_R_BAD_PASSWORD_READ:
4025 		case PEM_R_PROBLEMS_GETTING_PASSWORD:
4026 		case PEM_R_BAD_DECRYPT:
4027 			return SSH_ERR_KEY_WRONG_PASSPHRASE;
4028 		default:
4029 			return SSH_ERR_INVALID_FORMAT;
4030 		}
4031 	case ERR_LIB_EVP:
4032 		switch (pem_reason) {
4033 		case EVP_R_BAD_DECRYPT:
4034 			return SSH_ERR_KEY_WRONG_PASSPHRASE;
4035 #ifdef EVP_R_BN_DECODE_ERROR
4036 		case EVP_R_BN_DECODE_ERROR:
4037 #endif
4038 		case EVP_R_DECODE_ERROR:
4039 #ifdef EVP_R_PRIVATE_KEY_DECODE_ERROR
4040 		case EVP_R_PRIVATE_KEY_DECODE_ERROR:
4041 #endif
4042 			return SSH_ERR_INVALID_FORMAT;
4043 		default:
4044 			return SSH_ERR_LIBCRYPTO_ERROR;
4045 		}
4046 	case ERR_LIB_ASN1:
4047 		return SSH_ERR_INVALID_FORMAT;
4048 	}
4049 	return SSH_ERR_LIBCRYPTO_ERROR;
4050 }
4051 
4052 static void
4053 clear_libcrypto_errors(void)
4054 {
4055 	while (ERR_get_error() != 0)
4056 		;
4057 }
4058 
4059 /*
4060  * Translate OpenSSL error codes to determine whether
4061  * passphrase is required/incorrect.
4062  */
4063 static int
4064 convert_libcrypto_error(void)
4065 {
4066 	/*
4067 	 * Some password errors are reported at the beginning
4068 	 * of the error queue.
4069 	 */
4070 	if (translate_libcrypto_error(ERR_peek_error()) ==
4071 	    SSH_ERR_KEY_WRONG_PASSPHRASE)
4072 		return SSH_ERR_KEY_WRONG_PASSPHRASE;
4073 	return translate_libcrypto_error(ERR_peek_last_error());
4074 }
4075 
4076 static int
4077 sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
4078     const char *passphrase, struct sshkey **keyp)
4079 {
4080 	EVP_PKEY *pk = NULL;
4081 	struct sshkey *prv = NULL;
4082 	BIO *bio = NULL;
4083 	int r;
4084 
4085 	if (keyp != NULL)
4086 		*keyp = NULL;
4087 
4088 	if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
4089 		return SSH_ERR_ALLOC_FAIL;
4090 	if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) !=
4091 	    (int)sshbuf_len(blob)) {
4092 		r = SSH_ERR_ALLOC_FAIL;
4093 		goto out;
4094 	}
4095 
4096 	clear_libcrypto_errors();
4097 	if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL,
4098 	    (char *)passphrase)) == NULL) {
4099 	       /*
4100 		* libcrypto may return various ASN.1 errors when attempting
4101 		* to parse a key with an incorrect passphrase.
4102 		* Treat all format errors as "incorrect passphrase" if a
4103 		* passphrase was supplied.
4104 		*/
4105 		if (passphrase != NULL && *passphrase != '\0')
4106 			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
4107 		else
4108 			r = convert_libcrypto_error();
4109 		goto out;
4110 	}
4111 	if (EVP_PKEY_base_id(pk) == EVP_PKEY_RSA &&
4112 	    (type == KEY_UNSPEC || type == KEY_RSA)) {
4113 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
4114 			r = SSH_ERR_ALLOC_FAIL;
4115 			goto out;
4116 		}
4117 		prv->rsa = EVP_PKEY_get1_RSA(pk);
4118 		prv->type = KEY_RSA;
4119 #ifdef DEBUG_PK
4120 		RSA_print_fp(stderr, prv->rsa, 8);
4121 #endif
4122 		if (RSA_blinding_on(prv->rsa, NULL) != 1) {
4123 			r = SSH_ERR_LIBCRYPTO_ERROR;
4124 			goto out;
4125 		}
4126 		if ((r = check_rsa_length(prv->rsa)) != 0)
4127 			goto out;
4128 	} else if (EVP_PKEY_base_id(pk) == EVP_PKEY_DSA &&
4129 	    (type == KEY_UNSPEC || type == KEY_DSA)) {
4130 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
4131 			r = SSH_ERR_ALLOC_FAIL;
4132 			goto out;
4133 		}
4134 		prv->dsa = EVP_PKEY_get1_DSA(pk);
4135 		prv->type = KEY_DSA;
4136 #ifdef DEBUG_PK
4137 		DSA_print_fp(stderr, prv->dsa, 8);
4138 #endif
4139 	} else if (EVP_PKEY_base_id(pk) == EVP_PKEY_EC &&
4140 	    (type == KEY_UNSPEC || type == KEY_ECDSA)) {
4141 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
4142 			r = SSH_ERR_ALLOC_FAIL;
4143 			goto out;
4144 		}
4145 		prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
4146 		prv->type = KEY_ECDSA;
4147 		prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa);
4148 		if (prv->ecdsa_nid == -1 ||
4149 		    sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
4150 		    sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
4151 		    EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
4152 		    sshkey_ec_validate_private(prv->ecdsa) != 0) {
4153 			r = SSH_ERR_INVALID_FORMAT;
4154 			goto out;
4155 		}
4156 #ifdef DEBUG_PK
4157 		if (prv != NULL && prv->ecdsa != NULL)
4158 			sshkey_dump_ec_key(prv->ecdsa);
4159 #endif
4160 	} else {
4161 		r = SSH_ERR_INVALID_FORMAT;
4162 		goto out;
4163 	}
4164 	r = 0;
4165 	if (keyp != NULL) {
4166 		*keyp = prv;
4167 		prv = NULL;
4168 	}
4169  out:
4170 	BIO_free(bio);
4171 	EVP_PKEY_free(pk);
4172 	sshkey_free(prv);
4173 	return r;
4174 }
4175 #endif /* WITH_OPENSSL */
4176 
4177 int
4178 sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
4179     const char *passphrase, struct sshkey **keyp, char **commentp)
4180 {
4181 	int r = SSH_ERR_INTERNAL_ERROR;
4182 
4183 	if (keyp != NULL)
4184 		*keyp = NULL;
4185 	if (commentp != NULL)
4186 		*commentp = NULL;
4187 
4188 	switch (type) {
4189 #ifdef WITH_OPENSSL
4190 	case KEY_DSA:
4191 	case KEY_ECDSA:
4192 	case KEY_RSA:
4193 		return sshkey_parse_private_pem_fileblob(blob, type,
4194 		    passphrase, keyp);
4195 #endif /* WITH_OPENSSL */
4196 	case KEY_ED25519:
4197 #ifdef WITH_XMSS
4198 	case KEY_XMSS:
4199 #endif /* WITH_XMSS */
4200 		return sshkey_parse_private2(blob, type, passphrase,
4201 		    keyp, commentp);
4202 	case KEY_UNSPEC:
4203 		r = sshkey_parse_private2(blob, type, passphrase, keyp,
4204 		    commentp);
4205 		/* Do not fallback to PEM parser if only passphrase is wrong. */
4206 		if (r == 0 || r == SSH_ERR_KEY_WRONG_PASSPHRASE)
4207 			return r;
4208 #ifdef WITH_OPENSSL
4209 		return sshkey_parse_private_pem_fileblob(blob, type,
4210 		    passphrase, keyp);
4211 #else
4212 		return SSH_ERR_INVALID_FORMAT;
4213 #endif /* WITH_OPENSSL */
4214 	default:
4215 		return SSH_ERR_KEY_TYPE_UNKNOWN;
4216 	}
4217 }
4218 
4219 int
4220 sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase,
4221     struct sshkey **keyp, char **commentp)
4222 {
4223 	if (keyp != NULL)
4224 		*keyp = NULL;
4225 	if (commentp != NULL)
4226 		*commentp = NULL;
4227 
4228 	return sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
4229 	    passphrase, keyp, commentp);
4230 }
4231 
4232 #ifdef WITH_XMSS
4233 /*
4234  * serialize the key with the current state and forward the state
4235  * maxsign times.
4236  */
4237 int
4238 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b,
4239     u_int32_t maxsign, sshkey_printfn *pr)
4240 {
4241 	int r, rupdate;
4242 
4243 	if (maxsign == 0 ||
4244 	    sshkey_type_plain(k->type) != KEY_XMSS)
4245 		return sshkey_private_serialize_opt(k, b,
4246 		    SSHKEY_SERIALIZE_DEFAULT);
4247 	if ((r = sshkey_xmss_get_state(k, pr)) != 0 ||
4248 	    (r = sshkey_private_serialize_opt(k, b,
4249 	    SSHKEY_SERIALIZE_STATE)) != 0 ||
4250 	    (r = sshkey_xmss_forward_state(k, maxsign)) != 0)
4251 		goto out;
4252 	r = 0;
4253 out:
4254 	if ((rupdate = sshkey_xmss_update_state(k, pr)) != 0) {
4255 		if (r == 0)
4256 			r = rupdate;
4257 	}
4258 	return r;
4259 }
4260 
4261 u_int32_t
4262 sshkey_signatures_left(const struct sshkey *k)
4263 {
4264 	if (sshkey_type_plain(k->type) == KEY_XMSS)
4265 		return sshkey_xmss_signatures_left(k);
4266 	return 0;
4267 }
4268 
4269 int
4270 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
4271 {
4272 	if (sshkey_type_plain(k->type) != KEY_XMSS)
4273 		return SSH_ERR_INVALID_ARGUMENT;
4274 	return sshkey_xmss_enable_maxsign(k, maxsign);
4275 }
4276 
4277 int
4278 sshkey_set_filename(struct sshkey *k, const char *filename)
4279 {
4280 	if (k == NULL)
4281 		return SSH_ERR_INVALID_ARGUMENT;
4282 	if (sshkey_type_plain(k->type) != KEY_XMSS)
4283 		return 0;
4284 	if (filename == NULL)
4285 		return SSH_ERR_INVALID_ARGUMENT;
4286 	if ((k->xmss_filename = strdup(filename)) == NULL)
4287 		return SSH_ERR_ALLOC_FAIL;
4288 	return 0;
4289 }
4290 #else
4291 int
4292 sshkey_private_serialize_maxsign(struct sshkey *k, struct sshbuf *b,
4293     u_int32_t maxsign, sshkey_printfn *pr)
4294 {
4295 	return sshkey_private_serialize_opt(k, b, SSHKEY_SERIALIZE_DEFAULT);
4296 }
4297 
4298 u_int32_t
4299 sshkey_signatures_left(const struct sshkey *k)
4300 {
4301 	return 0;
4302 }
4303 
4304 int
4305 sshkey_enable_maxsign(struct sshkey *k, u_int32_t maxsign)
4306 {
4307 	return SSH_ERR_INVALID_ARGUMENT;
4308 }
4309 
4310 int
4311 sshkey_set_filename(struct sshkey *k, const char *filename)
4312 {
4313 	if (k == NULL)
4314 		return SSH_ERR_INVALID_ARGUMENT;
4315 	return 0;
4316 }
4317 #endif /* WITH_XMSS */
4318