xref: /openbsd-src/usr.bin/ssh/sshkey.c (revision 9b9d2a55a62c8e82206c25f94fcc7f4e2765250e)
1 /* $OpenBSD: sshkey.c,v 1.21 2015/08/19 23:19:01 djm Exp $ */
2 /*
3  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
4  * Copyright (c) 2008 Alexander von Gernler.  All rights reserved.
5  * Copyright (c) 2010,2011 Damien Miller.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>	/* MIN MAX */
29 #include <sys/types.h>
30 #include <netinet/in.h>
31 
32 #ifdef WITH_OPENSSL
33 #include <openssl/evp.h>
34 #include <openssl/err.h>
35 #include <openssl/pem.h>
36 #endif
37 
38 #include "crypto_api.h"
39 
40 #include <errno.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <util.h>
44 #include <limits.h>
45 #include <resolv.h>
46 
47 #include "ssh2.h"
48 #include "ssherr.h"
49 #include "misc.h"
50 #include "sshbuf.h"
51 #include "rsa.h"
52 #include "cipher.h"
53 #include "digest.h"
54 #define SSHKEY_INTERNAL
55 #include "sshkey.h"
56 #include "match.h"
57 
58 /* openssh private key file format */
59 #define MARK_BEGIN		"-----BEGIN OPENSSH PRIVATE KEY-----\n"
60 #define MARK_END		"-----END OPENSSH PRIVATE KEY-----\n"
61 #define MARK_BEGIN_LEN		(sizeof(MARK_BEGIN) - 1)
62 #define MARK_END_LEN		(sizeof(MARK_END) - 1)
63 #define KDFNAME			"bcrypt"
64 #define AUTH_MAGIC		"openssh-key-v1"
65 #define SALT_LEN		16
66 #define DEFAULT_CIPHERNAME	"aes256-cbc"
67 #define	DEFAULT_ROUNDS		16
68 
69 /* Version identification string for SSH v1 identity files. */
70 #define LEGACY_BEGIN		"SSH PRIVATE KEY FILE FORMAT 1.1\n"
71 
72 static int sshkey_from_blob_internal(struct sshbuf *buf,
73     struct sshkey **keyp, int allow_cert);
74 
75 /* Supported key types */
76 struct keytype {
77 	const char *name;
78 	const char *shortname;
79 	int type;
80 	int nid;
81 	int cert;
82 };
83 static const struct keytype keytypes[] = {
84 	{ "ssh-ed25519", "ED25519", KEY_ED25519, 0, 0 },
85 	{ "ssh-ed25519-cert-v01@openssh.com", "ED25519-CERT",
86 	    KEY_ED25519_CERT, 0, 1 },
87 #ifdef WITH_OPENSSL
88 	{ NULL, "RSA1", KEY_RSA1, 0, 0 },
89 	{ "ssh-rsa", "RSA", KEY_RSA, 0, 0 },
90 	{ "ssh-dss", "DSA", KEY_DSA, 0, 0 },
91 	{ "ecdsa-sha2-nistp256", "ECDSA", KEY_ECDSA, NID_X9_62_prime256v1, 0 },
92 	{ "ecdsa-sha2-nistp384", "ECDSA", KEY_ECDSA, NID_secp384r1, 0 },
93 	{ "ecdsa-sha2-nistp521", "ECDSA", KEY_ECDSA, NID_secp521r1, 0 },
94 	{ "ssh-rsa-cert-v01@openssh.com", "RSA-CERT", KEY_RSA_CERT, 0, 1 },
95 	{ "ssh-dss-cert-v01@openssh.com", "DSA-CERT", KEY_DSA_CERT, 0, 1 },
96 	{ "ecdsa-sha2-nistp256-cert-v01@openssh.com", "ECDSA-CERT",
97 	    KEY_ECDSA_CERT, NID_X9_62_prime256v1, 1 },
98 	{ "ecdsa-sha2-nistp384-cert-v01@openssh.com", "ECDSA-CERT",
99 	    KEY_ECDSA_CERT, NID_secp384r1, 1 },
100 	{ "ecdsa-sha2-nistp521-cert-v01@openssh.com", "ECDSA-CERT",
101 	    KEY_ECDSA_CERT, NID_secp521r1, 1 },
102 #endif /* WITH_OPENSSL */
103 	{ NULL, NULL, -1, -1, 0 }
104 };
105 
106 const char *
107 sshkey_type(const struct sshkey *k)
108 {
109 	const struct keytype *kt;
110 
111 	for (kt = keytypes; kt->type != -1; kt++) {
112 		if (kt->type == k->type)
113 			return kt->shortname;
114 	}
115 	return "unknown";
116 }
117 
118 static const char *
119 sshkey_ssh_name_from_type_nid(int type, int nid)
120 {
121 	const struct keytype *kt;
122 
123 	for (kt = keytypes; kt->type != -1; kt++) {
124 		if (kt->type == type && (kt->nid == 0 || kt->nid == nid))
125 			return kt->name;
126 	}
127 	return "ssh-unknown";
128 }
129 
130 int
131 sshkey_type_is_cert(int type)
132 {
133 	const struct keytype *kt;
134 
135 	for (kt = keytypes; kt->type != -1; kt++) {
136 		if (kt->type == type)
137 			return kt->cert;
138 	}
139 	return 0;
140 }
141 
142 const char *
143 sshkey_ssh_name(const struct sshkey *k)
144 {
145 	return sshkey_ssh_name_from_type_nid(k->type, k->ecdsa_nid);
146 }
147 
148 const char *
149 sshkey_ssh_name_plain(const struct sshkey *k)
150 {
151 	return sshkey_ssh_name_from_type_nid(sshkey_type_plain(k->type),
152 	    k->ecdsa_nid);
153 }
154 
155 int
156 sshkey_type_from_name(const char *name)
157 {
158 	const struct keytype *kt;
159 
160 	for (kt = keytypes; kt->type != -1; kt++) {
161 		/* Only allow shortname matches for plain key types */
162 		if ((kt->name != NULL && strcmp(name, kt->name) == 0) ||
163 		    (!kt->cert && strcasecmp(kt->shortname, name) == 0))
164 			return kt->type;
165 	}
166 	return KEY_UNSPEC;
167 }
168 
169 int
170 sshkey_ecdsa_nid_from_name(const char *name)
171 {
172 	const struct keytype *kt;
173 
174 	for (kt = keytypes; kt->type != -1; kt++) {
175 		if (kt->type != KEY_ECDSA && kt->type != KEY_ECDSA_CERT)
176 			continue;
177 		if (kt->name != NULL && strcmp(name, kt->name) == 0)
178 			return kt->nid;
179 	}
180 	return -1;
181 }
182 
183 char *
184 key_alg_list(int certs_only, int plain_only)
185 {
186 	char *tmp, *ret = NULL;
187 	size_t nlen, rlen = 0;
188 	const struct keytype *kt;
189 
190 	for (kt = keytypes; kt->type != -1; kt++) {
191 		if (kt->name == NULL)
192 			continue;
193 		if ((certs_only && !kt->cert) || (plain_only && kt->cert))
194 			continue;
195 		if (ret != NULL)
196 			ret[rlen++] = '\n';
197 		nlen = strlen(kt->name);
198 		if ((tmp = realloc(ret, rlen + nlen + 2)) == NULL) {
199 			free(ret);
200 			return NULL;
201 		}
202 		ret = tmp;
203 		memcpy(ret + rlen, kt->name, nlen + 1);
204 		rlen += nlen;
205 	}
206 	return ret;
207 }
208 
209 int
210 sshkey_names_valid2(const char *names, int allow_wildcard)
211 {
212 	char *s, *cp, *p;
213 	const struct keytype *kt;
214 	int type;
215 
216 	if (names == NULL || strcmp(names, "") == 0)
217 		return 0;
218 	if ((s = cp = strdup(names)) == NULL)
219 		return 0;
220 	for ((p = strsep(&cp, ",")); p && *p != '\0';
221 	    (p = strsep(&cp, ","))) {
222 		type = sshkey_type_from_name(p);
223 		if (type == KEY_RSA1) {
224 			free(s);
225 			return 0;
226 		}
227 		if (type == KEY_UNSPEC) {
228 			if (allow_wildcard) {
229 				/*
230 				 * Try matching key types against the string.
231 				 * If any has a positive or negative match then
232 				 * the component is accepted.
233 				 */
234 				for (kt = keytypes; kt->type != -1; kt++) {
235 					if (kt->type == KEY_RSA1)
236 						continue;
237 					if (match_pattern_list(kt->name,
238 					    p, 0) != 0)
239 						break;
240 				}
241 				if (kt->type != -1)
242 					continue;
243 			}
244 			free(s);
245 			return 0;
246 		}
247 	}
248 	free(s);
249 	return 1;
250 }
251 
252 u_int
253 sshkey_size(const struct sshkey *k)
254 {
255 	switch (k->type) {
256 #ifdef WITH_OPENSSL
257 	case KEY_RSA1:
258 	case KEY_RSA:
259 	case KEY_RSA_CERT:
260 		return BN_num_bits(k->rsa->n);
261 	case KEY_DSA:
262 	case KEY_DSA_CERT:
263 		return BN_num_bits(k->dsa->p);
264 	case KEY_ECDSA:
265 	case KEY_ECDSA_CERT:
266 		return sshkey_curve_nid_to_bits(k->ecdsa_nid);
267 #endif /* WITH_OPENSSL */
268 	case KEY_ED25519:
269 	case KEY_ED25519_CERT:
270 		return 256;	/* XXX */
271 	}
272 	return 0;
273 }
274 
275 static int
276 sshkey_type_is_valid_ca(int type)
277 {
278 	switch (type) {
279 	case KEY_RSA:
280 	case KEY_DSA:
281 	case KEY_ECDSA:
282 	case KEY_ED25519:
283 		return 1;
284 	default:
285 		return 0;
286 	}
287 }
288 
289 int
290 sshkey_is_cert(const struct sshkey *k)
291 {
292 	if (k == NULL)
293 		return 0;
294 	return sshkey_type_is_cert(k->type);
295 }
296 
297 /* Return the cert-less equivalent to a certified key type */
298 int
299 sshkey_type_plain(int type)
300 {
301 	switch (type) {
302 	case KEY_RSA_CERT:
303 		return KEY_RSA;
304 	case KEY_DSA_CERT:
305 		return KEY_DSA;
306 	case KEY_ECDSA_CERT:
307 		return KEY_ECDSA;
308 	case KEY_ED25519_CERT:
309 		return KEY_ED25519;
310 	default:
311 		return type;
312 	}
313 }
314 
315 #ifdef WITH_OPENSSL
316 /* XXX: these are really begging for a table-driven approach */
317 int
318 sshkey_curve_name_to_nid(const char *name)
319 {
320 	if (strcmp(name, "nistp256") == 0)
321 		return NID_X9_62_prime256v1;
322 	else if (strcmp(name, "nistp384") == 0)
323 		return NID_secp384r1;
324 	else if (strcmp(name, "nistp521") == 0)
325 		return NID_secp521r1;
326 	else
327 		return -1;
328 }
329 
330 u_int
331 sshkey_curve_nid_to_bits(int nid)
332 {
333 	switch (nid) {
334 	case NID_X9_62_prime256v1:
335 		return 256;
336 	case NID_secp384r1:
337 		return 384;
338 	case NID_secp521r1:
339 		return 521;
340 	default:
341 		return 0;
342 	}
343 }
344 
345 int
346 sshkey_ecdsa_bits_to_nid(int bits)
347 {
348 	switch (bits) {
349 	case 256:
350 		return NID_X9_62_prime256v1;
351 	case 384:
352 		return NID_secp384r1;
353 	case 521:
354 		return NID_secp521r1;
355 	default:
356 		return -1;
357 	}
358 }
359 
360 const char *
361 sshkey_curve_nid_to_name(int nid)
362 {
363 	switch (nid) {
364 	case NID_X9_62_prime256v1:
365 		return "nistp256";
366 	case NID_secp384r1:
367 		return "nistp384";
368 	case NID_secp521r1:
369 		return "nistp521";
370 	default:
371 		return NULL;
372 	}
373 }
374 
375 int
376 sshkey_ec_nid_to_hash_alg(int nid)
377 {
378 	int kbits = sshkey_curve_nid_to_bits(nid);
379 
380 	if (kbits <= 0)
381 		return -1;
382 
383 	/* RFC5656 section 6.2.1 */
384 	if (kbits <= 256)
385 		return SSH_DIGEST_SHA256;
386 	else if (kbits <= 384)
387 		return SSH_DIGEST_SHA384;
388 	else
389 		return SSH_DIGEST_SHA512;
390 }
391 #endif /* WITH_OPENSSL */
392 
393 static void
394 cert_free(struct sshkey_cert *cert)
395 {
396 	u_int i;
397 
398 	if (cert == NULL)
399 		return;
400 	if (cert->certblob != NULL)
401 		sshbuf_free(cert->certblob);
402 	if (cert->critical != NULL)
403 		sshbuf_free(cert->critical);
404 	if (cert->extensions != NULL)
405 		sshbuf_free(cert->extensions);
406 	if (cert->key_id != NULL)
407 		free(cert->key_id);
408 	for (i = 0; i < cert->nprincipals; i++)
409 		free(cert->principals[i]);
410 	if (cert->principals != NULL)
411 		free(cert->principals);
412 	if (cert->signature_key != NULL)
413 		sshkey_free(cert->signature_key);
414 	explicit_bzero(cert, sizeof(*cert));
415 	free(cert);
416 }
417 
418 static struct sshkey_cert *
419 cert_new(void)
420 {
421 	struct sshkey_cert *cert;
422 
423 	if ((cert = calloc(1, sizeof(*cert))) == NULL)
424 		return NULL;
425 	if ((cert->certblob = sshbuf_new()) == NULL ||
426 	    (cert->critical = sshbuf_new()) == NULL ||
427 	    (cert->extensions = sshbuf_new()) == NULL) {
428 		cert_free(cert);
429 		return NULL;
430 	}
431 	cert->key_id = NULL;
432 	cert->principals = NULL;
433 	cert->signature_key = NULL;
434 	return cert;
435 }
436 
437 struct sshkey *
438 sshkey_new(int type)
439 {
440 	struct sshkey *k;
441 #ifdef WITH_OPENSSL
442 	RSA *rsa;
443 	DSA *dsa;
444 #endif /* WITH_OPENSSL */
445 
446 	if ((k = calloc(1, sizeof(*k))) == NULL)
447 		return NULL;
448 	k->type = type;
449 	k->ecdsa = NULL;
450 	k->ecdsa_nid = -1;
451 	k->dsa = NULL;
452 	k->rsa = NULL;
453 	k->cert = NULL;
454 	k->ed25519_sk = NULL;
455 	k->ed25519_pk = NULL;
456 	switch (k->type) {
457 #ifdef WITH_OPENSSL
458 	case KEY_RSA1:
459 	case KEY_RSA:
460 	case KEY_RSA_CERT:
461 		if ((rsa = RSA_new()) == NULL ||
462 		    (rsa->n = BN_new()) == NULL ||
463 		    (rsa->e = BN_new()) == NULL) {
464 			if (rsa != NULL)
465 				RSA_free(rsa);
466 			free(k);
467 			return NULL;
468 		}
469 		k->rsa = rsa;
470 		break;
471 	case KEY_DSA:
472 	case KEY_DSA_CERT:
473 		if ((dsa = DSA_new()) == NULL ||
474 		    (dsa->p = BN_new()) == NULL ||
475 		    (dsa->q = BN_new()) == NULL ||
476 		    (dsa->g = BN_new()) == NULL ||
477 		    (dsa->pub_key = BN_new()) == NULL) {
478 			if (dsa != NULL)
479 				DSA_free(dsa);
480 			free(k);
481 			return NULL;
482 		}
483 		k->dsa = dsa;
484 		break;
485 	case KEY_ECDSA:
486 	case KEY_ECDSA_CERT:
487 		/* Cannot do anything until we know the group */
488 		break;
489 #endif /* WITH_OPENSSL */
490 	case KEY_ED25519:
491 	case KEY_ED25519_CERT:
492 		/* no need to prealloc */
493 		break;
494 	case KEY_UNSPEC:
495 		break;
496 	default:
497 		free(k);
498 		return NULL;
499 		break;
500 	}
501 
502 	if (sshkey_is_cert(k)) {
503 		if ((k->cert = cert_new()) == NULL) {
504 			sshkey_free(k);
505 			return NULL;
506 		}
507 	}
508 
509 	return k;
510 }
511 
512 int
513 sshkey_add_private(struct sshkey *k)
514 {
515 	switch (k->type) {
516 #ifdef WITH_OPENSSL
517 	case KEY_RSA1:
518 	case KEY_RSA:
519 	case KEY_RSA_CERT:
520 #define bn_maybe_alloc_failed(p) (p == NULL && (p = BN_new()) == NULL)
521 		if (bn_maybe_alloc_failed(k->rsa->d) ||
522 		    bn_maybe_alloc_failed(k->rsa->iqmp) ||
523 		    bn_maybe_alloc_failed(k->rsa->q) ||
524 		    bn_maybe_alloc_failed(k->rsa->p) ||
525 		    bn_maybe_alloc_failed(k->rsa->dmq1) ||
526 		    bn_maybe_alloc_failed(k->rsa->dmp1))
527 			return SSH_ERR_ALLOC_FAIL;
528 		break;
529 	case KEY_DSA:
530 	case KEY_DSA_CERT:
531 		if (bn_maybe_alloc_failed(k->dsa->priv_key))
532 			return SSH_ERR_ALLOC_FAIL;
533 		break;
534 #undef bn_maybe_alloc_failed
535 	case KEY_ECDSA:
536 	case KEY_ECDSA_CERT:
537 		/* Cannot do anything until we know the group */
538 		break;
539 #endif /* WITH_OPENSSL */
540 	case KEY_ED25519:
541 	case KEY_ED25519_CERT:
542 		/* no need to prealloc */
543 		break;
544 	case KEY_UNSPEC:
545 		break;
546 	default:
547 		return SSH_ERR_INVALID_ARGUMENT;
548 	}
549 	return 0;
550 }
551 
552 struct sshkey *
553 sshkey_new_private(int type)
554 {
555 	struct sshkey *k = sshkey_new(type);
556 
557 	if (k == NULL)
558 		return NULL;
559 	if (sshkey_add_private(k) != 0) {
560 		sshkey_free(k);
561 		return NULL;
562 	}
563 	return k;
564 }
565 
566 void
567 sshkey_free(struct sshkey *k)
568 {
569 	if (k == NULL)
570 		return;
571 	switch (k->type) {
572 #ifdef WITH_OPENSSL
573 	case KEY_RSA1:
574 	case KEY_RSA:
575 	case KEY_RSA_CERT:
576 		if (k->rsa != NULL)
577 			RSA_free(k->rsa);
578 		k->rsa = NULL;
579 		break;
580 	case KEY_DSA:
581 	case KEY_DSA_CERT:
582 		if (k->dsa != NULL)
583 			DSA_free(k->dsa);
584 		k->dsa = NULL;
585 		break;
586 	case KEY_ECDSA:
587 	case KEY_ECDSA_CERT:
588 		if (k->ecdsa != NULL)
589 			EC_KEY_free(k->ecdsa);
590 		k->ecdsa = NULL;
591 		break;
592 #endif /* WITH_OPENSSL */
593 	case KEY_ED25519:
594 	case KEY_ED25519_CERT:
595 		if (k->ed25519_pk) {
596 			explicit_bzero(k->ed25519_pk, ED25519_PK_SZ);
597 			free(k->ed25519_pk);
598 			k->ed25519_pk = NULL;
599 		}
600 		if (k->ed25519_sk) {
601 			explicit_bzero(k->ed25519_sk, ED25519_SK_SZ);
602 			free(k->ed25519_sk);
603 			k->ed25519_sk = NULL;
604 		}
605 		break;
606 	case KEY_UNSPEC:
607 		break;
608 	default:
609 		break;
610 	}
611 	if (sshkey_is_cert(k))
612 		cert_free(k->cert);
613 	explicit_bzero(k, sizeof(*k));
614 	free(k);
615 }
616 
617 static int
618 cert_compare(struct sshkey_cert *a, struct sshkey_cert *b)
619 {
620 	if (a == NULL && b == NULL)
621 		return 1;
622 	if (a == NULL || b == NULL)
623 		return 0;
624 	if (sshbuf_len(a->certblob) != sshbuf_len(b->certblob))
625 		return 0;
626 	if (timingsafe_bcmp(sshbuf_ptr(a->certblob), sshbuf_ptr(b->certblob),
627 	    sshbuf_len(a->certblob)) != 0)
628 		return 0;
629 	return 1;
630 }
631 
632 /*
633  * Compare public portions of key only, allowing comparisons between
634  * certificates and plain keys too.
635  */
636 int
637 sshkey_equal_public(const struct sshkey *a, const struct sshkey *b)
638 {
639 #ifdef WITH_OPENSSL
640 	BN_CTX *bnctx;
641 #endif /* WITH_OPENSSL */
642 
643 	if (a == NULL || b == NULL ||
644 	    sshkey_type_plain(a->type) != sshkey_type_plain(b->type))
645 		return 0;
646 
647 	switch (a->type) {
648 #ifdef WITH_OPENSSL
649 	case KEY_RSA1:
650 	case KEY_RSA_CERT:
651 	case KEY_RSA:
652 		return a->rsa != NULL && b->rsa != NULL &&
653 		    BN_cmp(a->rsa->e, b->rsa->e) == 0 &&
654 		    BN_cmp(a->rsa->n, b->rsa->n) == 0;
655 	case KEY_DSA_CERT:
656 	case KEY_DSA:
657 		return a->dsa != NULL && b->dsa != NULL &&
658 		    BN_cmp(a->dsa->p, b->dsa->p) == 0 &&
659 		    BN_cmp(a->dsa->q, b->dsa->q) == 0 &&
660 		    BN_cmp(a->dsa->g, b->dsa->g) == 0 &&
661 		    BN_cmp(a->dsa->pub_key, b->dsa->pub_key) == 0;
662 	case KEY_ECDSA_CERT:
663 	case KEY_ECDSA:
664 		if (a->ecdsa == NULL || b->ecdsa == NULL ||
665 		    EC_KEY_get0_public_key(a->ecdsa) == NULL ||
666 		    EC_KEY_get0_public_key(b->ecdsa) == NULL)
667 			return 0;
668 		if ((bnctx = BN_CTX_new()) == NULL)
669 			return 0;
670 		if (EC_GROUP_cmp(EC_KEY_get0_group(a->ecdsa),
671 		    EC_KEY_get0_group(b->ecdsa), bnctx) != 0 ||
672 		    EC_POINT_cmp(EC_KEY_get0_group(a->ecdsa),
673 		    EC_KEY_get0_public_key(a->ecdsa),
674 		    EC_KEY_get0_public_key(b->ecdsa), bnctx) != 0) {
675 			BN_CTX_free(bnctx);
676 			return 0;
677 		}
678 		BN_CTX_free(bnctx);
679 		return 1;
680 #endif /* WITH_OPENSSL */
681 	case KEY_ED25519:
682 	case KEY_ED25519_CERT:
683 		return a->ed25519_pk != NULL && b->ed25519_pk != NULL &&
684 		    memcmp(a->ed25519_pk, b->ed25519_pk, ED25519_PK_SZ) == 0;
685 	default:
686 		return 0;
687 	}
688 	/* NOTREACHED */
689 }
690 
691 int
692 sshkey_equal(const struct sshkey *a, const struct sshkey *b)
693 {
694 	if (a == NULL || b == NULL || a->type != b->type)
695 		return 0;
696 	if (sshkey_is_cert(a)) {
697 		if (!cert_compare(a->cert, b->cert))
698 			return 0;
699 	}
700 	return sshkey_equal_public(a, b);
701 }
702 
703 static int
704 to_blob_buf(const struct sshkey *key, struct sshbuf *b, int force_plain)
705 {
706 	int type, ret = SSH_ERR_INTERNAL_ERROR;
707 	const char *typename;
708 
709 	if (key == NULL)
710 		return SSH_ERR_INVALID_ARGUMENT;
711 
712 	if (sshkey_is_cert(key)) {
713 		if (key->cert == NULL)
714 			return SSH_ERR_EXPECTED_CERT;
715 		if (sshbuf_len(key->cert->certblob) == 0)
716 			return SSH_ERR_KEY_LACKS_CERTBLOB;
717 	}
718 	type = force_plain ? sshkey_type_plain(key->type) : key->type;
719 	typename = sshkey_ssh_name_from_type_nid(type, key->ecdsa_nid);
720 
721 	switch (type) {
722 #ifdef WITH_OPENSSL
723 	case KEY_DSA_CERT:
724 	case KEY_ECDSA_CERT:
725 	case KEY_RSA_CERT:
726 #endif /* WITH_OPENSSL */
727 	case KEY_ED25519_CERT:
728 		/* Use the existing blob */
729 		/* XXX modified flag? */
730 		if ((ret = sshbuf_putb(b, key->cert->certblob)) != 0)
731 			return ret;
732 		break;
733 #ifdef WITH_OPENSSL
734 	case KEY_DSA:
735 		if (key->dsa == NULL)
736 			return SSH_ERR_INVALID_ARGUMENT;
737 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
738 		    (ret = sshbuf_put_bignum2(b, key->dsa->p)) != 0 ||
739 		    (ret = sshbuf_put_bignum2(b, key->dsa->q)) != 0 ||
740 		    (ret = sshbuf_put_bignum2(b, key->dsa->g)) != 0 ||
741 		    (ret = sshbuf_put_bignum2(b, key->dsa->pub_key)) != 0)
742 			return ret;
743 		break;
744 	case KEY_ECDSA:
745 		if (key->ecdsa == NULL)
746 			return SSH_ERR_INVALID_ARGUMENT;
747 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
748 		    (ret = sshbuf_put_cstring(b,
749 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
750 		    (ret = sshbuf_put_eckey(b, key->ecdsa)) != 0)
751 			return ret;
752 		break;
753 	case KEY_RSA:
754 		if (key->rsa == NULL)
755 			return SSH_ERR_INVALID_ARGUMENT;
756 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
757 		    (ret = sshbuf_put_bignum2(b, key->rsa->e)) != 0 ||
758 		    (ret = sshbuf_put_bignum2(b, key->rsa->n)) != 0)
759 			return ret;
760 		break;
761 #endif /* WITH_OPENSSL */
762 	case KEY_ED25519:
763 		if (key->ed25519_pk == NULL)
764 			return SSH_ERR_INVALID_ARGUMENT;
765 		if ((ret = sshbuf_put_cstring(b, typename)) != 0 ||
766 		    (ret = sshbuf_put_string(b,
767 		    key->ed25519_pk, ED25519_PK_SZ)) != 0)
768 			return ret;
769 		break;
770 	default:
771 		return SSH_ERR_KEY_TYPE_UNKNOWN;
772 	}
773 	return 0;
774 }
775 
776 int
777 sshkey_putb(const struct sshkey *key, struct sshbuf *b)
778 {
779 	return to_blob_buf(key, b, 0);
780 }
781 
782 int
783 sshkey_puts(const struct sshkey *key, struct sshbuf *b)
784 {
785 	struct sshbuf *tmp;
786 	int r;
787 
788 	if ((tmp = sshbuf_new()) == NULL)
789 		return SSH_ERR_ALLOC_FAIL;
790 	r = to_blob_buf(key, tmp, 0);
791 	if (r == 0)
792 		r = sshbuf_put_stringb(b, tmp);
793 	sshbuf_free(tmp);
794 	return r;
795 }
796 
797 int
798 sshkey_putb_plain(const struct sshkey *key, struct sshbuf *b)
799 {
800 	return to_blob_buf(key, b, 1);
801 }
802 
803 static int
804 to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp, int force_plain)
805 {
806 	int ret = SSH_ERR_INTERNAL_ERROR;
807 	size_t len;
808 	struct sshbuf *b = NULL;
809 
810 	if (lenp != NULL)
811 		*lenp = 0;
812 	if (blobp != NULL)
813 		*blobp = NULL;
814 	if ((b = sshbuf_new()) == NULL)
815 		return SSH_ERR_ALLOC_FAIL;
816 	if ((ret = to_blob_buf(key, b, force_plain)) != 0)
817 		goto out;
818 	len = sshbuf_len(b);
819 	if (lenp != NULL)
820 		*lenp = len;
821 	if (blobp != NULL) {
822 		if ((*blobp = malloc(len)) == NULL) {
823 			ret = SSH_ERR_ALLOC_FAIL;
824 			goto out;
825 		}
826 		memcpy(*blobp, sshbuf_ptr(b), len);
827 	}
828 	ret = 0;
829  out:
830 	sshbuf_free(b);
831 	return ret;
832 }
833 
834 int
835 sshkey_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
836 {
837 	return to_blob(key, blobp, lenp, 0);
838 }
839 
840 int
841 sshkey_plain_to_blob(const struct sshkey *key, u_char **blobp, size_t *lenp)
842 {
843 	return to_blob(key, blobp, lenp, 1);
844 }
845 
846 int
847 sshkey_fingerprint_raw(const struct sshkey *k, int dgst_alg,
848     u_char **retp, size_t *lenp)
849 {
850 	u_char *blob = NULL, *ret = NULL;
851 	size_t blob_len = 0;
852 	int r = SSH_ERR_INTERNAL_ERROR;
853 
854 	if (retp != NULL)
855 		*retp = NULL;
856 	if (lenp != NULL)
857 		*lenp = 0;
858 	if (ssh_digest_bytes(dgst_alg) == 0) {
859 		r = SSH_ERR_INVALID_ARGUMENT;
860 		goto out;
861 	}
862 
863 	if (k->type == KEY_RSA1) {
864 #ifdef WITH_OPENSSL
865 		int nlen = BN_num_bytes(k->rsa->n);
866 		int elen = BN_num_bytes(k->rsa->e);
867 
868 		blob_len = nlen + elen;
869 		if (nlen >= INT_MAX - elen ||
870 		    (blob = malloc(blob_len)) == NULL) {
871 			r = SSH_ERR_ALLOC_FAIL;
872 			goto out;
873 		}
874 		BN_bn2bin(k->rsa->n, blob);
875 		BN_bn2bin(k->rsa->e, blob + nlen);
876 #endif /* WITH_OPENSSL */
877 	} else if ((r = to_blob(k, &blob, &blob_len, 1)) != 0)
878 		goto out;
879 	if ((ret = calloc(1, SSH_DIGEST_MAX_LENGTH)) == NULL) {
880 		r = SSH_ERR_ALLOC_FAIL;
881 		goto out;
882 	}
883 	if ((r = ssh_digest_memory(dgst_alg, blob, blob_len,
884 	    ret, SSH_DIGEST_MAX_LENGTH)) != 0)
885 		goto out;
886 	/* success */
887 	if (retp != NULL) {
888 		*retp = ret;
889 		ret = NULL;
890 	}
891 	if (lenp != NULL)
892 		*lenp = ssh_digest_bytes(dgst_alg);
893 	r = 0;
894  out:
895 	free(ret);
896 	if (blob != NULL) {
897 		explicit_bzero(blob, blob_len);
898 		free(blob);
899 	}
900 	return r;
901 }
902 
903 static char *
904 fingerprint_b64(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
905 {
906 	char *ret;
907 	size_t plen = strlen(alg) + 1;
908 	size_t rlen = ((dgst_raw_len + 2) / 3) * 4 + plen + 1;
909 	int r;
910 
911 	if (dgst_raw_len > 65536 || (ret = calloc(1, rlen)) == NULL)
912 		return NULL;
913 	strlcpy(ret, alg, rlen);
914 	strlcat(ret, ":", rlen);
915 	if (dgst_raw_len == 0)
916 		return ret;
917 	if ((r = b64_ntop(dgst_raw, dgst_raw_len,
918 	    ret + plen, rlen - plen)) == -1) {
919 		explicit_bzero(ret, rlen);
920 		free(ret);
921 		return NULL;
922 	}
923 	/* Trim padding characters from end */
924 	ret[strcspn(ret, "=")] = '\0';
925 	return ret;
926 }
927 
928 static char *
929 fingerprint_hex(const char *alg, u_char *dgst_raw, size_t dgst_raw_len)
930 {
931 	char *retval, hex[5];
932 	size_t i, rlen = dgst_raw_len * 3 + strlen(alg) + 2;
933 
934 	if (dgst_raw_len > 65536 || (retval = calloc(1, rlen)) == NULL)
935 		return NULL;
936 	strlcpy(retval, alg, rlen);
937 	strlcat(retval, ":", rlen);
938 	for (i = 0; i < dgst_raw_len; i++) {
939 		snprintf(hex, sizeof(hex), "%s%02x",
940 		    i > 0 ? ":" : "", dgst_raw[i]);
941 		strlcat(retval, hex, rlen);
942 	}
943 	return retval;
944 }
945 
946 static char *
947 fingerprint_bubblebabble(u_char *dgst_raw, size_t dgst_raw_len)
948 {
949 	char vowels[] = { 'a', 'e', 'i', 'o', 'u', 'y' };
950 	char consonants[] = { 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm',
951 	    'n', 'p', 'r', 's', 't', 'v', 'z', 'x' };
952 	u_int i, j = 0, rounds, seed = 1;
953 	char *retval;
954 
955 	rounds = (dgst_raw_len / 2) + 1;
956 	if ((retval = calloc(rounds, 6)) == NULL)
957 		return NULL;
958 	retval[j++] = 'x';
959 	for (i = 0; i < rounds; i++) {
960 		u_int idx0, idx1, idx2, idx3, idx4;
961 		if ((i + 1 < rounds) || (dgst_raw_len % 2 != 0)) {
962 			idx0 = (((((u_int)(dgst_raw[2 * i])) >> 6) & 3) +
963 			    seed) % 6;
964 			idx1 = (((u_int)(dgst_raw[2 * i])) >> 2) & 15;
965 			idx2 = ((((u_int)(dgst_raw[2 * i])) & 3) +
966 			    (seed / 6)) % 6;
967 			retval[j++] = vowels[idx0];
968 			retval[j++] = consonants[idx1];
969 			retval[j++] = vowels[idx2];
970 			if ((i + 1) < rounds) {
971 				idx3 = (((u_int)(dgst_raw[(2 * i) + 1])) >> 4) & 15;
972 				idx4 = (((u_int)(dgst_raw[(2 * i) + 1]))) & 15;
973 				retval[j++] = consonants[idx3];
974 				retval[j++] = '-';
975 				retval[j++] = consonants[idx4];
976 				seed = ((seed * 5) +
977 				    ((((u_int)(dgst_raw[2 * i])) * 7) +
978 				    ((u_int)(dgst_raw[(2 * i) + 1])))) % 36;
979 			}
980 		} else {
981 			idx0 = seed % 6;
982 			idx1 = 16;
983 			idx2 = seed / 6;
984 			retval[j++] = vowels[idx0];
985 			retval[j++] = consonants[idx1];
986 			retval[j++] = vowels[idx2];
987 		}
988 	}
989 	retval[j++] = 'x';
990 	retval[j++] = '\0';
991 	return retval;
992 }
993 
994 /*
995  * Draw an ASCII-Art representing the fingerprint so human brain can
996  * profit from its built-in pattern recognition ability.
997  * This technique is called "random art" and can be found in some
998  * scientific publications like this original paper:
999  *
1000  * "Hash Visualization: a New Technique to improve Real-World Security",
1001  * Perrig A. and Song D., 1999, International Workshop on Cryptographic
1002  * Techniques and E-Commerce (CrypTEC '99)
1003  * sparrow.ece.cmu.edu/~adrian/projects/validation/validation.pdf
1004  *
1005  * The subject came up in a talk by Dan Kaminsky, too.
1006  *
1007  * If you see the picture is different, the key is different.
1008  * If the picture looks the same, you still know nothing.
1009  *
1010  * The algorithm used here is a worm crawling over a discrete plane,
1011  * leaving a trace (augmenting the field) everywhere it goes.
1012  * Movement is taken from dgst_raw 2bit-wise.  Bumping into walls
1013  * makes the respective movement vector be ignored for this turn.
1014  * Graphs are not unambiguous, because circles in graphs can be
1015  * walked in either direction.
1016  */
1017 
1018 /*
1019  * Field sizes for the random art.  Have to be odd, so the starting point
1020  * can be in the exact middle of the picture, and FLDBASE should be >=8 .
1021  * Else pictures would be too dense, and drawing the frame would
1022  * fail, too, because the key type would not fit in anymore.
1023  */
1024 #define	FLDBASE		8
1025 #define	FLDSIZE_Y	(FLDBASE + 1)
1026 #define	FLDSIZE_X	(FLDBASE * 2 + 1)
1027 static char *
1028 fingerprint_randomart(const char *alg, u_char *dgst_raw, size_t dgst_raw_len,
1029     const struct sshkey *k)
1030 {
1031 	/*
1032 	 * Chars to be used after each other every time the worm
1033 	 * intersects with itself.  Matter of taste.
1034 	 */
1035 	char	*augmentation_string = " .o+=*BOX@%&#/^SE";
1036 	char	*retval, *p, title[FLDSIZE_X], hash[FLDSIZE_X];
1037 	u_char	 field[FLDSIZE_X][FLDSIZE_Y];
1038 	size_t	 i, tlen, hlen;
1039 	u_int	 b;
1040 	int	 x, y, r;
1041 	size_t	 len = strlen(augmentation_string) - 1;
1042 
1043 	if ((retval = calloc((FLDSIZE_X + 3), (FLDSIZE_Y + 2))) == NULL)
1044 		return NULL;
1045 
1046 	/* initialize field */
1047 	memset(field, 0, FLDSIZE_X * FLDSIZE_Y * sizeof(char));
1048 	x = FLDSIZE_X / 2;
1049 	y = FLDSIZE_Y / 2;
1050 
1051 	/* process raw key */
1052 	for (i = 0; i < dgst_raw_len; i++) {
1053 		int input;
1054 		/* each byte conveys four 2-bit move commands */
1055 		input = dgst_raw[i];
1056 		for (b = 0; b < 4; b++) {
1057 			/* evaluate 2 bit, rest is shifted later */
1058 			x += (input & 0x1) ? 1 : -1;
1059 			y += (input & 0x2) ? 1 : -1;
1060 
1061 			/* assure we are still in bounds */
1062 			x = MAX(x, 0);
1063 			y = MAX(y, 0);
1064 			x = MIN(x, FLDSIZE_X - 1);
1065 			y = MIN(y, FLDSIZE_Y - 1);
1066 
1067 			/* augment the field */
1068 			if (field[x][y] < len - 2)
1069 				field[x][y]++;
1070 			input = input >> 2;
1071 		}
1072 	}
1073 
1074 	/* mark starting point and end point*/
1075 	field[FLDSIZE_X / 2][FLDSIZE_Y / 2] = len - 1;
1076 	field[x][y] = len;
1077 
1078 	/* assemble title */
1079 	r = snprintf(title, sizeof(title), "[%s %u]",
1080 		sshkey_type(k), sshkey_size(k));
1081 	/* If [type size] won't fit, then try [type]; fits "[ED25519-CERT]" */
1082 	if (r < 0 || r > (int)sizeof(title))
1083 		r = snprintf(title, sizeof(title), "[%s]", sshkey_type(k));
1084 	tlen = (r <= 0) ? 0 : strlen(title);
1085 
1086 	/* assemble hash ID. */
1087 	r = snprintf(hash, sizeof(hash), "[%s]", alg);
1088 	hlen = (r <= 0) ? 0 : strlen(hash);
1089 
1090 	/* output upper border */
1091 	p = retval;
1092 	*p++ = '+';
1093 	for (i = 0; i < (FLDSIZE_X - tlen) / 2; i++)
1094 		*p++ = '-';
1095 	memcpy(p, title, tlen);
1096 	p += tlen;
1097 	for (i += tlen; i < FLDSIZE_X; i++)
1098 		*p++ = '-';
1099 	*p++ = '+';
1100 	*p++ = '\n';
1101 
1102 	/* output content */
1103 	for (y = 0; y < FLDSIZE_Y; y++) {
1104 		*p++ = '|';
1105 		for (x = 0; x < FLDSIZE_X; x++)
1106 			*p++ = augmentation_string[MIN(field[x][y], len)];
1107 		*p++ = '|';
1108 		*p++ = '\n';
1109 	}
1110 
1111 	/* output lower border */
1112 	*p++ = '+';
1113 	for (i = 0; i < (FLDSIZE_X - hlen) / 2; i++)
1114 		*p++ = '-';
1115 	memcpy(p, hash, hlen);
1116 	p += hlen;
1117 	for (i += hlen; i < FLDSIZE_X; i++)
1118 		*p++ = '-';
1119 	*p++ = '+';
1120 
1121 	return retval;
1122 }
1123 
1124 char *
1125 sshkey_fingerprint(const struct sshkey *k, int dgst_alg,
1126     enum sshkey_fp_rep dgst_rep)
1127 {
1128 	char *retval = NULL;
1129 	u_char *dgst_raw;
1130 	size_t dgst_raw_len;
1131 
1132 	if (sshkey_fingerprint_raw(k, dgst_alg, &dgst_raw, &dgst_raw_len) != 0)
1133 		return NULL;
1134 	switch (dgst_rep) {
1135 	case SSH_FP_DEFAULT:
1136 		if (dgst_alg == SSH_DIGEST_MD5) {
1137 			retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1138 			    dgst_raw, dgst_raw_len);
1139 		} else {
1140 			retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1141 			    dgst_raw, dgst_raw_len);
1142 		}
1143 		break;
1144 	case SSH_FP_HEX:
1145 		retval = fingerprint_hex(ssh_digest_alg_name(dgst_alg),
1146 		    dgst_raw, dgst_raw_len);
1147 		break;
1148 	case SSH_FP_BASE64:
1149 		retval = fingerprint_b64(ssh_digest_alg_name(dgst_alg),
1150 		    dgst_raw, dgst_raw_len);
1151 		break;
1152 	case SSH_FP_BUBBLEBABBLE:
1153 		retval = fingerprint_bubblebabble(dgst_raw, dgst_raw_len);
1154 		break;
1155 	case SSH_FP_RANDOMART:
1156 		retval = fingerprint_randomart(ssh_digest_alg_name(dgst_alg),
1157 		    dgst_raw, dgst_raw_len, k);
1158 		break;
1159 	default:
1160 		explicit_bzero(dgst_raw, dgst_raw_len);
1161 		free(dgst_raw);
1162 		return NULL;
1163 	}
1164 	explicit_bzero(dgst_raw, dgst_raw_len);
1165 	free(dgst_raw);
1166 	return retval;
1167 }
1168 
1169 #ifdef WITH_SSH1
1170 /*
1171  * Reads a multiple-precision integer in decimal from the buffer, and advances
1172  * the pointer.  The integer must already be initialized.  This function is
1173  * permitted to modify the buffer.  This leaves *cpp to point just beyond the
1174  * last processed character.
1175  */
1176 static int
1177 read_decimal_bignum(char **cpp, BIGNUM *v)
1178 {
1179 	char *cp;
1180 	size_t e;
1181 	int skip = 1;	/* skip white space */
1182 
1183 	cp = *cpp;
1184 	while (*cp == ' ' || *cp == '\t')
1185 		cp++;
1186 	e = strspn(cp, "0123456789");
1187 	if (e == 0)
1188 		return SSH_ERR_INVALID_FORMAT;
1189 	if (e > SSHBUF_MAX_BIGNUM * 3)
1190 		return SSH_ERR_BIGNUM_TOO_LARGE;
1191 	if (cp[e] == '\0')
1192 		skip = 0;
1193 	else if (index(" \t\r\n", cp[e]) == NULL)
1194 		return SSH_ERR_INVALID_FORMAT;
1195 	cp[e] = '\0';
1196 	if (BN_dec2bn(&v, cp) <= 0)
1197 		return SSH_ERR_INVALID_FORMAT;
1198 	*cpp = cp + e + skip;
1199 	return 0;
1200 }
1201 #endif /* WITH_SSH1 */
1202 
1203 /* returns 0 ok, and < 0 error */
1204 int
1205 sshkey_read(struct sshkey *ret, char **cpp)
1206 {
1207 	struct sshkey *k;
1208 	int retval = SSH_ERR_INVALID_FORMAT;
1209 	char *cp, *space;
1210 	int r, type, curve_nid = -1;
1211 	struct sshbuf *blob;
1212 #ifdef WITH_SSH1
1213 	char *ep;
1214 	u_long bits;
1215 #endif /* WITH_SSH1 */
1216 
1217 	cp = *cpp;
1218 
1219 	switch (ret->type) {
1220 	case KEY_RSA1:
1221 #ifdef WITH_SSH1
1222 		/* Get number of bits. */
1223 		bits = strtoul(cp, &ep, 10);
1224 		if (*cp == '\0' || index(" \t\r\n", *ep) == NULL ||
1225 		    bits == 0 || bits > SSHBUF_MAX_BIGNUM * 8)
1226 			return SSH_ERR_INVALID_FORMAT;	/* Bad bit count... */
1227 		/* Get public exponent, public modulus. */
1228 		if ((r = read_decimal_bignum(&ep, ret->rsa->e)) < 0)
1229 			return r;
1230 		if ((r = read_decimal_bignum(&ep, ret->rsa->n)) < 0)
1231 			return r;
1232 		*cpp = ep;
1233 		/* validate the claimed number of bits */
1234 		if (BN_num_bits(ret->rsa->n) != (int)bits)
1235 			return SSH_ERR_KEY_BITS_MISMATCH;
1236 		retval = 0;
1237 #endif /* WITH_SSH1 */
1238 		break;
1239 	case KEY_UNSPEC:
1240 	case KEY_RSA:
1241 	case KEY_DSA:
1242 	case KEY_ECDSA:
1243 	case KEY_ED25519:
1244 	case KEY_DSA_CERT:
1245 	case KEY_ECDSA_CERT:
1246 	case KEY_RSA_CERT:
1247 	case KEY_ED25519_CERT:
1248 		space = strchr(cp, ' ');
1249 		if (space == NULL)
1250 			return SSH_ERR_INVALID_FORMAT;
1251 		*space = '\0';
1252 		type = sshkey_type_from_name(cp);
1253 		if (sshkey_type_plain(type) == KEY_ECDSA &&
1254 		    (curve_nid = sshkey_ecdsa_nid_from_name(cp)) == -1)
1255 			return SSH_ERR_EC_CURVE_INVALID;
1256 		*space = ' ';
1257 		if (type == KEY_UNSPEC)
1258 			return SSH_ERR_INVALID_FORMAT;
1259 		cp = space+1;
1260 		if (*cp == '\0')
1261 			return SSH_ERR_INVALID_FORMAT;
1262 		if (ret->type != KEY_UNSPEC && ret->type != type)
1263 			return SSH_ERR_KEY_TYPE_MISMATCH;
1264 		if ((blob = sshbuf_new()) == NULL)
1265 			return SSH_ERR_ALLOC_FAIL;
1266 		/* trim comment */
1267 		space = strchr(cp, ' ');
1268 		if (space) {
1269 			/* advance 'space': skip whitespace */
1270 			*space++ = '\0';
1271 			while (*space == ' ' || *space == '\t')
1272 				space++;
1273 			*cpp = space;
1274 		} else
1275 			*cpp = cp + strlen(cp);
1276 		if ((r = sshbuf_b64tod(blob, cp)) != 0) {
1277 			sshbuf_free(blob);
1278 			return r;
1279 		}
1280 		if ((r = sshkey_from_blob(sshbuf_ptr(blob),
1281 		    sshbuf_len(blob), &k)) != 0) {
1282 			sshbuf_free(blob);
1283 			return r;
1284 		}
1285 		sshbuf_free(blob);
1286 		if (k->type != type) {
1287 			sshkey_free(k);
1288 			return SSH_ERR_KEY_TYPE_MISMATCH;
1289 		}
1290 		if (sshkey_type_plain(type) == KEY_ECDSA &&
1291 		    curve_nid != k->ecdsa_nid) {
1292 			sshkey_free(k);
1293 			return SSH_ERR_EC_CURVE_MISMATCH;
1294 		}
1295 		ret->type = type;
1296 		if (sshkey_is_cert(ret)) {
1297 			if (!sshkey_is_cert(k)) {
1298 				sshkey_free(k);
1299 				return SSH_ERR_EXPECTED_CERT;
1300 			}
1301 			if (ret->cert != NULL)
1302 				cert_free(ret->cert);
1303 			ret->cert = k->cert;
1304 			k->cert = NULL;
1305 		}
1306 #ifdef WITH_OPENSSL
1307 		if (sshkey_type_plain(ret->type) == KEY_RSA) {
1308 			if (ret->rsa != NULL)
1309 				RSA_free(ret->rsa);
1310 			ret->rsa = k->rsa;
1311 			k->rsa = NULL;
1312 #ifdef DEBUG_PK
1313 			RSA_print_fp(stderr, ret->rsa, 8);
1314 #endif
1315 		}
1316 		if (sshkey_type_plain(ret->type) == KEY_DSA) {
1317 			if (ret->dsa != NULL)
1318 				DSA_free(ret->dsa);
1319 			ret->dsa = k->dsa;
1320 			k->dsa = NULL;
1321 #ifdef DEBUG_PK
1322 			DSA_print_fp(stderr, ret->dsa, 8);
1323 #endif
1324 		}
1325 		if (sshkey_type_plain(ret->type) == KEY_ECDSA) {
1326 			if (ret->ecdsa != NULL)
1327 				EC_KEY_free(ret->ecdsa);
1328 			ret->ecdsa = k->ecdsa;
1329 			ret->ecdsa_nid = k->ecdsa_nid;
1330 			k->ecdsa = NULL;
1331 			k->ecdsa_nid = -1;
1332 #ifdef DEBUG_PK
1333 			sshkey_dump_ec_key(ret->ecdsa);
1334 #endif
1335 		}
1336 #endif /* WITH_OPENSSL */
1337 		if (sshkey_type_plain(ret->type) == KEY_ED25519) {
1338 			free(ret->ed25519_pk);
1339 			ret->ed25519_pk = k->ed25519_pk;
1340 			k->ed25519_pk = NULL;
1341 #ifdef DEBUG_PK
1342 			/* XXX */
1343 #endif
1344 		}
1345 		retval = 0;
1346 /*XXXX*/
1347 		sshkey_free(k);
1348 		if (retval != 0)
1349 			break;
1350 		break;
1351 	default:
1352 		return SSH_ERR_INVALID_ARGUMENT;
1353 	}
1354 	return retval;
1355 }
1356 
1357 int
1358 sshkey_to_base64(const struct sshkey *key, char **b64p)
1359 {
1360 	int r = SSH_ERR_INTERNAL_ERROR;
1361 	struct sshbuf *b = NULL;
1362 	char *uu = NULL;
1363 
1364 	if (b64p != NULL)
1365 		*b64p = NULL;
1366 	if ((b = sshbuf_new()) == NULL)
1367 		return SSH_ERR_ALLOC_FAIL;
1368 	if ((r = sshkey_putb(key, b)) != 0)
1369 		goto out;
1370 	if ((uu = sshbuf_dtob64(b)) == NULL) {
1371 		r = SSH_ERR_ALLOC_FAIL;
1372 		goto out;
1373 	}
1374 	/* Success */
1375 	if (b64p != NULL) {
1376 		*b64p = uu;
1377 		uu = NULL;
1378 	}
1379 	r = 0;
1380  out:
1381 	sshbuf_free(b);
1382 	free(uu);
1383 	return r;
1384 }
1385 
1386 static int
1387 sshkey_format_rsa1(const struct sshkey *key, struct sshbuf *b)
1388 {
1389 	int r = SSH_ERR_INTERNAL_ERROR;
1390 #ifdef WITH_SSH1
1391 	u_int bits = 0;
1392 	char *dec_e = NULL, *dec_n = NULL;
1393 
1394 	if (key->rsa == NULL || key->rsa->e == NULL ||
1395 	    key->rsa->n == NULL) {
1396 		r = SSH_ERR_INVALID_ARGUMENT;
1397 		goto out;
1398 	}
1399 	if ((dec_e = BN_bn2dec(key->rsa->e)) == NULL ||
1400 	    (dec_n = BN_bn2dec(key->rsa->n)) == NULL) {
1401 		r = SSH_ERR_ALLOC_FAIL;
1402 		goto out;
1403 	}
1404 	/* size of modulus 'n' */
1405 	if ((bits = BN_num_bits(key->rsa->n)) <= 0) {
1406 		r = SSH_ERR_INVALID_ARGUMENT;
1407 		goto out;
1408 	}
1409 	if ((r = sshbuf_putf(b, "%u %s %s", bits, dec_e, dec_n)) != 0)
1410 		goto out;
1411 
1412 	/* Success */
1413 	r = 0;
1414  out:
1415 	if (dec_e != NULL)
1416 		OPENSSL_free(dec_e);
1417 	if (dec_n != NULL)
1418 		OPENSSL_free(dec_n);
1419 #endif /* WITH_SSH1 */
1420 
1421 	return r;
1422 }
1423 
1424 static int
1425 sshkey_format_text(const struct sshkey *key, struct sshbuf *b)
1426 {
1427 	int r = SSH_ERR_INTERNAL_ERROR;
1428 	char *uu = NULL;
1429 
1430 	if (key->type == KEY_RSA1) {
1431 		if ((r = sshkey_format_rsa1(key, b)) != 0)
1432 			goto out;
1433 	} else {
1434 		/* Unsupported key types handled in sshkey_to_base64() */
1435 		if ((r = sshkey_to_base64(key, &uu)) != 0)
1436 			goto out;
1437 		if ((r = sshbuf_putf(b, "%s %s",
1438 		    sshkey_ssh_name(key), uu)) != 0)
1439 			goto out;
1440 	}
1441 	r = 0;
1442  out:
1443 	free(uu);
1444 	return r;
1445 }
1446 
1447 int
1448 sshkey_write(const struct sshkey *key, FILE *f)
1449 {
1450 	struct sshbuf *b = NULL;
1451 	int r = SSH_ERR_INTERNAL_ERROR;
1452 
1453 	if ((b = sshbuf_new()) == NULL)
1454 		return SSH_ERR_ALLOC_FAIL;
1455 	if ((r = sshkey_format_text(key, b)) != 0)
1456 		goto out;
1457 	if (fwrite(sshbuf_ptr(b), sshbuf_len(b), 1, f) != 1) {
1458 		if (feof(f))
1459 			errno = EPIPE;
1460 		r = SSH_ERR_SYSTEM_ERROR;
1461 		goto out;
1462 	}
1463 	/* Success */
1464 	r = 0;
1465  out:
1466 	sshbuf_free(b);
1467 	return r;
1468 }
1469 
1470 const char *
1471 sshkey_cert_type(const struct sshkey *k)
1472 {
1473 	switch (k->cert->type) {
1474 	case SSH2_CERT_TYPE_USER:
1475 		return "user";
1476 	case SSH2_CERT_TYPE_HOST:
1477 		return "host";
1478 	default:
1479 		return "unknown";
1480 	}
1481 }
1482 
1483 #ifdef WITH_OPENSSL
1484 static int
1485 rsa_generate_private_key(u_int bits, RSA **rsap)
1486 {
1487 	RSA *private = NULL;
1488 	BIGNUM *f4 = NULL;
1489 	int ret = SSH_ERR_INTERNAL_ERROR;
1490 
1491 	if (rsap == NULL ||
1492 	    bits < SSH_RSA_MINIMUM_MODULUS_SIZE ||
1493 	    bits > SSHBUF_MAX_BIGNUM * 8)
1494 		return SSH_ERR_INVALID_ARGUMENT;
1495 	*rsap = NULL;
1496 	if ((private = RSA_new()) == NULL || (f4 = BN_new()) == NULL) {
1497 		ret = SSH_ERR_ALLOC_FAIL;
1498 		goto out;
1499 	}
1500 	if (!BN_set_word(f4, RSA_F4) ||
1501 	    !RSA_generate_key_ex(private, bits, f4, NULL)) {
1502 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1503 		goto out;
1504 	}
1505 	*rsap = private;
1506 	private = NULL;
1507 	ret = 0;
1508  out:
1509 	if (private != NULL)
1510 		RSA_free(private);
1511 	if (f4 != NULL)
1512 		BN_free(f4);
1513 	return ret;
1514 }
1515 
1516 static int
1517 dsa_generate_private_key(u_int bits, DSA **dsap)
1518 {
1519 	DSA *private;
1520 	int ret = SSH_ERR_INTERNAL_ERROR;
1521 
1522 	if (dsap == NULL || bits != 1024)
1523 		return SSH_ERR_INVALID_ARGUMENT;
1524 	if ((private = DSA_new()) == NULL) {
1525 		ret = SSH_ERR_ALLOC_FAIL;
1526 		goto out;
1527 	}
1528 	*dsap = NULL;
1529 	if (!DSA_generate_parameters_ex(private, bits, NULL, 0, NULL,
1530 	    NULL, NULL) || !DSA_generate_key(private)) {
1531 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1532 		goto out;
1533 	}
1534 	*dsap = private;
1535 	private = NULL;
1536 	ret = 0;
1537  out:
1538 	if (private != NULL)
1539 		DSA_free(private);
1540 	return ret;
1541 }
1542 
1543 int
1544 sshkey_ecdsa_key_to_nid(EC_KEY *k)
1545 {
1546 	EC_GROUP *eg;
1547 	int nids[] = {
1548 		NID_X9_62_prime256v1,
1549 		NID_secp384r1,
1550 		NID_secp521r1,
1551 		-1
1552 	};
1553 	int nid;
1554 	u_int i;
1555 	BN_CTX *bnctx;
1556 	const EC_GROUP *g = EC_KEY_get0_group(k);
1557 
1558 	/*
1559 	 * The group may be stored in a ASN.1 encoded private key in one of two
1560 	 * ways: as a "named group", which is reconstituted by ASN.1 object ID
1561 	 * or explicit group parameters encoded into the key blob. Only the
1562 	 * "named group" case sets the group NID for us, but we can figure
1563 	 * it out for the other case by comparing against all the groups that
1564 	 * are supported.
1565 	 */
1566 	if ((nid = EC_GROUP_get_curve_name(g)) > 0)
1567 		return nid;
1568 	if ((bnctx = BN_CTX_new()) == NULL)
1569 		return -1;
1570 	for (i = 0; nids[i] != -1; i++) {
1571 		if ((eg = EC_GROUP_new_by_curve_name(nids[i])) == NULL) {
1572 			BN_CTX_free(bnctx);
1573 			return -1;
1574 		}
1575 		if (EC_GROUP_cmp(g, eg, bnctx) == 0)
1576 			break;
1577 		EC_GROUP_free(eg);
1578 	}
1579 	BN_CTX_free(bnctx);
1580 	if (nids[i] != -1) {
1581 		/* Use the group with the NID attached */
1582 		EC_GROUP_set_asn1_flag(eg, OPENSSL_EC_NAMED_CURVE);
1583 		if (EC_KEY_set_group(k, eg) != 1) {
1584 			EC_GROUP_free(eg);
1585 			return -1;
1586 		}
1587 	}
1588 	return nids[i];
1589 }
1590 
1591 static int
1592 ecdsa_generate_private_key(u_int bits, int *nid, EC_KEY **ecdsap)
1593 {
1594 	EC_KEY *private;
1595 	int ret = SSH_ERR_INTERNAL_ERROR;
1596 
1597 	if (nid == NULL || ecdsap == NULL ||
1598 	    (*nid = sshkey_ecdsa_bits_to_nid(bits)) == -1)
1599 		return SSH_ERR_INVALID_ARGUMENT;
1600 	*ecdsap = NULL;
1601 	if ((private = EC_KEY_new_by_curve_name(*nid)) == NULL) {
1602 		ret = SSH_ERR_ALLOC_FAIL;
1603 		goto out;
1604 	}
1605 	if (EC_KEY_generate_key(private) != 1) {
1606 		ret = SSH_ERR_LIBCRYPTO_ERROR;
1607 		goto out;
1608 	}
1609 	EC_KEY_set_asn1_flag(private, OPENSSL_EC_NAMED_CURVE);
1610 	*ecdsap = private;
1611 	private = NULL;
1612 	ret = 0;
1613  out:
1614 	if (private != NULL)
1615 		EC_KEY_free(private);
1616 	return ret;
1617 }
1618 #endif /* WITH_OPENSSL */
1619 
1620 int
1621 sshkey_generate(int type, u_int bits, struct sshkey **keyp)
1622 {
1623 	struct sshkey *k;
1624 	int ret = SSH_ERR_INTERNAL_ERROR;
1625 
1626 	if (keyp == NULL)
1627 		return SSH_ERR_INVALID_ARGUMENT;
1628 	*keyp = NULL;
1629 	if ((k = sshkey_new(KEY_UNSPEC)) == NULL)
1630 		return SSH_ERR_ALLOC_FAIL;
1631 	switch (type) {
1632 	case KEY_ED25519:
1633 		if ((k->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL ||
1634 		    (k->ed25519_sk = malloc(ED25519_SK_SZ)) == NULL) {
1635 			ret = SSH_ERR_ALLOC_FAIL;
1636 			break;
1637 		}
1638 		crypto_sign_ed25519_keypair(k->ed25519_pk, k->ed25519_sk);
1639 		ret = 0;
1640 		break;
1641 #ifdef WITH_OPENSSL
1642 	case KEY_DSA:
1643 		ret = dsa_generate_private_key(bits, &k->dsa);
1644 		break;
1645 	case KEY_ECDSA:
1646 		ret = ecdsa_generate_private_key(bits, &k->ecdsa_nid,
1647 		    &k->ecdsa);
1648 		break;
1649 	case KEY_RSA:
1650 	case KEY_RSA1:
1651 		ret = rsa_generate_private_key(bits, &k->rsa);
1652 		break;
1653 #endif /* WITH_OPENSSL */
1654 	default:
1655 		ret = SSH_ERR_INVALID_ARGUMENT;
1656 	}
1657 	if (ret == 0) {
1658 		k->type = type;
1659 		*keyp = k;
1660 	} else
1661 		sshkey_free(k);
1662 	return ret;
1663 }
1664 
1665 int
1666 sshkey_cert_copy(const struct sshkey *from_key, struct sshkey *to_key)
1667 {
1668 	u_int i;
1669 	const struct sshkey_cert *from;
1670 	struct sshkey_cert *to;
1671 	int ret = SSH_ERR_INTERNAL_ERROR;
1672 
1673 	if (to_key->cert != NULL) {
1674 		cert_free(to_key->cert);
1675 		to_key->cert = NULL;
1676 	}
1677 
1678 	if ((from = from_key->cert) == NULL)
1679 		return SSH_ERR_INVALID_ARGUMENT;
1680 
1681 	if ((to = to_key->cert = cert_new()) == NULL)
1682 		return SSH_ERR_ALLOC_FAIL;
1683 
1684 	if ((ret = sshbuf_putb(to->certblob, from->certblob)) != 0 ||
1685 	    (ret = sshbuf_putb(to->critical, from->critical)) != 0 ||
1686 	    (ret = sshbuf_putb(to->extensions, from->extensions) != 0))
1687 		return ret;
1688 
1689 	to->serial = from->serial;
1690 	to->type = from->type;
1691 	if (from->key_id == NULL)
1692 		to->key_id = NULL;
1693 	else if ((to->key_id = strdup(from->key_id)) == NULL)
1694 		return SSH_ERR_ALLOC_FAIL;
1695 	to->valid_after = from->valid_after;
1696 	to->valid_before = from->valid_before;
1697 	if (from->signature_key == NULL)
1698 		to->signature_key = NULL;
1699 	else if ((ret = sshkey_from_private(from->signature_key,
1700 	    &to->signature_key)) != 0)
1701 		return ret;
1702 
1703 	if (from->nprincipals > SSHKEY_CERT_MAX_PRINCIPALS)
1704 		return SSH_ERR_INVALID_ARGUMENT;
1705 	if (from->nprincipals > 0) {
1706 		if ((to->principals = calloc(from->nprincipals,
1707 		    sizeof(*to->principals))) == NULL)
1708 			return SSH_ERR_ALLOC_FAIL;
1709 		for (i = 0; i < from->nprincipals; i++) {
1710 			to->principals[i] = strdup(from->principals[i]);
1711 			if (to->principals[i] == NULL) {
1712 				to->nprincipals = i;
1713 				return SSH_ERR_ALLOC_FAIL;
1714 			}
1715 		}
1716 	}
1717 	to->nprincipals = from->nprincipals;
1718 	return 0;
1719 }
1720 
1721 int
1722 sshkey_from_private(const struct sshkey *k, struct sshkey **pkp)
1723 {
1724 	struct sshkey *n = NULL;
1725 	int ret = SSH_ERR_INTERNAL_ERROR;
1726 
1727 	if (pkp != NULL)
1728 		*pkp = NULL;
1729 
1730 	switch (k->type) {
1731 #ifdef WITH_OPENSSL
1732 	case KEY_DSA:
1733 	case KEY_DSA_CERT:
1734 		if ((n = sshkey_new(k->type)) == NULL)
1735 			return SSH_ERR_ALLOC_FAIL;
1736 		if ((BN_copy(n->dsa->p, k->dsa->p) == NULL) ||
1737 		    (BN_copy(n->dsa->q, k->dsa->q) == NULL) ||
1738 		    (BN_copy(n->dsa->g, k->dsa->g) == NULL) ||
1739 		    (BN_copy(n->dsa->pub_key, k->dsa->pub_key) == NULL)) {
1740 			sshkey_free(n);
1741 			return SSH_ERR_ALLOC_FAIL;
1742 		}
1743 		break;
1744 	case KEY_ECDSA:
1745 	case KEY_ECDSA_CERT:
1746 		if ((n = sshkey_new(k->type)) == NULL)
1747 			return SSH_ERR_ALLOC_FAIL;
1748 		n->ecdsa_nid = k->ecdsa_nid;
1749 		n->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
1750 		if (n->ecdsa == NULL) {
1751 			sshkey_free(n);
1752 			return SSH_ERR_ALLOC_FAIL;
1753 		}
1754 		if (EC_KEY_set_public_key(n->ecdsa,
1755 		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
1756 			sshkey_free(n);
1757 			return SSH_ERR_LIBCRYPTO_ERROR;
1758 		}
1759 		break;
1760 	case KEY_RSA:
1761 	case KEY_RSA1:
1762 	case KEY_RSA_CERT:
1763 		if ((n = sshkey_new(k->type)) == NULL)
1764 			return SSH_ERR_ALLOC_FAIL;
1765 		if ((BN_copy(n->rsa->n, k->rsa->n) == NULL) ||
1766 		    (BN_copy(n->rsa->e, k->rsa->e) == NULL)) {
1767 			sshkey_free(n);
1768 			return SSH_ERR_ALLOC_FAIL;
1769 		}
1770 		break;
1771 #endif /* WITH_OPENSSL */
1772 	case KEY_ED25519:
1773 	case KEY_ED25519_CERT:
1774 		if ((n = sshkey_new(k->type)) == NULL)
1775 			return SSH_ERR_ALLOC_FAIL;
1776 		if (k->ed25519_pk != NULL) {
1777 			if ((n->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
1778 				sshkey_free(n);
1779 				return SSH_ERR_ALLOC_FAIL;
1780 			}
1781 			memcpy(n->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
1782 		}
1783 		break;
1784 	default:
1785 		return SSH_ERR_KEY_TYPE_UNKNOWN;
1786 	}
1787 	if (sshkey_is_cert(k)) {
1788 		if ((ret = sshkey_cert_copy(k, n)) != 0) {
1789 			sshkey_free(n);
1790 			return ret;
1791 		}
1792 	}
1793 	*pkp = n;
1794 	return 0;
1795 }
1796 
1797 static int
1798 cert_parse(struct sshbuf *b, struct sshkey *key, struct sshbuf *certbuf)
1799 {
1800 	struct sshbuf *principals = NULL, *crit = NULL;
1801 	struct sshbuf *exts = NULL, *ca = NULL;
1802 	u_char *sig = NULL;
1803 	size_t signed_len = 0, slen = 0, kidlen = 0;
1804 	int ret = SSH_ERR_INTERNAL_ERROR;
1805 
1806 	/* Copy the entire key blob for verification and later serialisation */
1807 	if ((ret = sshbuf_putb(key->cert->certblob, certbuf)) != 0)
1808 		return ret;
1809 
1810 	/* Parse body of certificate up to signature */
1811 	if ((ret = sshbuf_get_u64(b, &key->cert->serial)) != 0 ||
1812 	    (ret = sshbuf_get_u32(b, &key->cert->type)) != 0 ||
1813 	    (ret = sshbuf_get_cstring(b, &key->cert->key_id, &kidlen)) != 0 ||
1814 	    (ret = sshbuf_froms(b, &principals)) != 0 ||
1815 	    (ret = sshbuf_get_u64(b, &key->cert->valid_after)) != 0 ||
1816 	    (ret = sshbuf_get_u64(b, &key->cert->valid_before)) != 0 ||
1817 	    (ret = sshbuf_froms(b, &crit)) != 0 ||
1818 	    (ret = sshbuf_froms(b, &exts)) != 0 ||
1819 	    (ret = sshbuf_get_string_direct(b, NULL, NULL)) != 0 ||
1820 	    (ret = sshbuf_froms(b, &ca)) != 0) {
1821 		/* XXX debug print error for ret */
1822 		ret = SSH_ERR_INVALID_FORMAT;
1823 		goto out;
1824 	}
1825 
1826 	/* Signature is left in the buffer so we can calculate this length */
1827 	signed_len = sshbuf_len(key->cert->certblob) - sshbuf_len(b);
1828 
1829 	if ((ret = sshbuf_get_string(b, &sig, &slen)) != 0) {
1830 		ret = SSH_ERR_INVALID_FORMAT;
1831 		goto out;
1832 	}
1833 
1834 	if (key->cert->type != SSH2_CERT_TYPE_USER &&
1835 	    key->cert->type != SSH2_CERT_TYPE_HOST) {
1836 		ret = SSH_ERR_KEY_CERT_UNKNOWN_TYPE;
1837 		goto out;
1838 	}
1839 
1840 	/* Parse principals section */
1841 	while (sshbuf_len(principals) > 0) {
1842 		char *principal = NULL;
1843 		char **oprincipals = NULL;
1844 
1845 		if (key->cert->nprincipals >= SSHKEY_CERT_MAX_PRINCIPALS) {
1846 			ret = SSH_ERR_INVALID_FORMAT;
1847 			goto out;
1848 		}
1849 		if ((ret = sshbuf_get_cstring(principals, &principal,
1850 		    NULL)) != 0) {
1851 			ret = SSH_ERR_INVALID_FORMAT;
1852 			goto out;
1853 		}
1854 		oprincipals = key->cert->principals;
1855 		key->cert->principals = reallocarray(key->cert->principals,
1856 		    key->cert->nprincipals + 1, sizeof(*key->cert->principals));
1857 		if (key->cert->principals == NULL) {
1858 			free(principal);
1859 			key->cert->principals = oprincipals;
1860 			ret = SSH_ERR_ALLOC_FAIL;
1861 			goto out;
1862 		}
1863 		key->cert->principals[key->cert->nprincipals++] = principal;
1864 	}
1865 
1866 	/*
1867 	 * Stash a copies of the critical options and extensions sections
1868 	 * for later use.
1869 	 */
1870 	if ((ret = sshbuf_putb(key->cert->critical, crit)) != 0 ||
1871 	    (exts != NULL &&
1872 	    (ret = sshbuf_putb(key->cert->extensions, exts)) != 0))
1873 		goto out;
1874 
1875 	/*
1876 	 * Validate critical options and extensions sections format.
1877 	 */
1878 	while (sshbuf_len(crit) != 0) {
1879 		if ((ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0 ||
1880 		    (ret = sshbuf_get_string_direct(crit, NULL, NULL)) != 0) {
1881 			sshbuf_reset(key->cert->critical);
1882 			ret = SSH_ERR_INVALID_FORMAT;
1883 			goto out;
1884 		}
1885 	}
1886 	while (exts != NULL && sshbuf_len(exts) != 0) {
1887 		if ((ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0 ||
1888 		    (ret = sshbuf_get_string_direct(exts, NULL, NULL)) != 0) {
1889 			sshbuf_reset(key->cert->extensions);
1890 			ret = SSH_ERR_INVALID_FORMAT;
1891 			goto out;
1892 		}
1893 	}
1894 
1895 	/* Parse CA key and check signature */
1896 	if (sshkey_from_blob_internal(ca, &key->cert->signature_key, 0) != 0) {
1897 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1898 		goto out;
1899 	}
1900 	if (!sshkey_type_is_valid_ca(key->cert->signature_key->type)) {
1901 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1902 		goto out;
1903 	}
1904 	if ((ret = sshkey_verify(key->cert->signature_key, sig, slen,
1905 	    sshbuf_ptr(key->cert->certblob), signed_len, 0)) != 0)
1906 		goto out;
1907 
1908 	/* Success */
1909 	ret = 0;
1910  out:
1911 	sshbuf_free(ca);
1912 	sshbuf_free(crit);
1913 	sshbuf_free(exts);
1914 	sshbuf_free(principals);
1915 	free(sig);
1916 	return ret;
1917 }
1918 
1919 static int
1920 sshkey_from_blob_internal(struct sshbuf *b, struct sshkey **keyp,
1921     int allow_cert)
1922 {
1923 	int type, ret = SSH_ERR_INTERNAL_ERROR;
1924 	char *ktype = NULL, *curve = NULL;
1925 	struct sshkey *key = NULL;
1926 	size_t len;
1927 	u_char *pk = NULL;
1928 	struct sshbuf *copy;
1929 #ifdef WITH_OPENSSL
1930 	EC_POINT *q = NULL;
1931 #endif /* WITH_OPENSSL */
1932 
1933 #ifdef DEBUG_PK /* XXX */
1934 	sshbuf_dump(b, stderr);
1935 #endif
1936 	*keyp = NULL;
1937 	if ((copy = sshbuf_fromb(b)) == NULL) {
1938 		ret = SSH_ERR_ALLOC_FAIL;
1939 		goto out;
1940 	}
1941 	if (sshbuf_get_cstring(b, &ktype, NULL) != 0) {
1942 		ret = SSH_ERR_INVALID_FORMAT;
1943 		goto out;
1944 	}
1945 
1946 	type = sshkey_type_from_name(ktype);
1947 	if (!allow_cert && sshkey_type_is_cert(type)) {
1948 		ret = SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
1949 		goto out;
1950 	}
1951 	switch (type) {
1952 #ifdef WITH_OPENSSL
1953 	case KEY_RSA_CERT:
1954 		/* Skip nonce */
1955 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
1956 			ret = SSH_ERR_INVALID_FORMAT;
1957 			goto out;
1958 		}
1959 		/* FALLTHROUGH */
1960 	case KEY_RSA:
1961 		if ((key = sshkey_new(type)) == NULL) {
1962 			ret = SSH_ERR_ALLOC_FAIL;
1963 			goto out;
1964 		}
1965 		if (sshbuf_get_bignum2(b, key->rsa->e) != 0 ||
1966 		    sshbuf_get_bignum2(b, key->rsa->n) != 0) {
1967 			ret = SSH_ERR_INVALID_FORMAT;
1968 			goto out;
1969 		}
1970 #ifdef DEBUG_PK
1971 		RSA_print_fp(stderr, key->rsa, 8);
1972 #endif
1973 		break;
1974 	case KEY_DSA_CERT:
1975 		/* Skip nonce */
1976 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
1977 			ret = SSH_ERR_INVALID_FORMAT;
1978 			goto out;
1979 		}
1980 		/* FALLTHROUGH */
1981 	case KEY_DSA:
1982 		if ((key = sshkey_new(type)) == NULL) {
1983 			ret = SSH_ERR_ALLOC_FAIL;
1984 			goto out;
1985 		}
1986 		if (sshbuf_get_bignum2(b, key->dsa->p) != 0 ||
1987 		    sshbuf_get_bignum2(b, key->dsa->q) != 0 ||
1988 		    sshbuf_get_bignum2(b, key->dsa->g) != 0 ||
1989 		    sshbuf_get_bignum2(b, key->dsa->pub_key) != 0) {
1990 			ret = SSH_ERR_INVALID_FORMAT;
1991 			goto out;
1992 		}
1993 #ifdef DEBUG_PK
1994 		DSA_print_fp(stderr, key->dsa, 8);
1995 #endif
1996 		break;
1997 	case KEY_ECDSA_CERT:
1998 		/* Skip nonce */
1999 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2000 			ret = SSH_ERR_INVALID_FORMAT;
2001 			goto out;
2002 		}
2003 		/* FALLTHROUGH */
2004 	case KEY_ECDSA:
2005 		if ((key = sshkey_new(type)) == NULL) {
2006 			ret = SSH_ERR_ALLOC_FAIL;
2007 			goto out;
2008 		}
2009 		key->ecdsa_nid = sshkey_ecdsa_nid_from_name(ktype);
2010 		if (sshbuf_get_cstring(b, &curve, NULL) != 0) {
2011 			ret = SSH_ERR_INVALID_FORMAT;
2012 			goto out;
2013 		}
2014 		if (key->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
2015 			ret = SSH_ERR_EC_CURVE_MISMATCH;
2016 			goto out;
2017 		}
2018 		if (key->ecdsa != NULL)
2019 			EC_KEY_free(key->ecdsa);
2020 		if ((key->ecdsa = EC_KEY_new_by_curve_name(key->ecdsa_nid))
2021 		    == NULL) {
2022 			ret = SSH_ERR_EC_CURVE_INVALID;
2023 			goto out;
2024 		}
2025 		if ((q = EC_POINT_new(EC_KEY_get0_group(key->ecdsa))) == NULL) {
2026 			ret = SSH_ERR_ALLOC_FAIL;
2027 			goto out;
2028 		}
2029 		if (sshbuf_get_ec(b, q, EC_KEY_get0_group(key->ecdsa)) != 0) {
2030 			ret = SSH_ERR_INVALID_FORMAT;
2031 			goto out;
2032 		}
2033 		if (sshkey_ec_validate_public(EC_KEY_get0_group(key->ecdsa),
2034 		    q) != 0) {
2035 			ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2036 			goto out;
2037 		}
2038 		if (EC_KEY_set_public_key(key->ecdsa, q) != 1) {
2039 			/* XXX assume it is a allocation error */
2040 			ret = SSH_ERR_ALLOC_FAIL;
2041 			goto out;
2042 		}
2043 #ifdef DEBUG_PK
2044 		sshkey_dump_ec_point(EC_KEY_get0_group(key->ecdsa), q);
2045 #endif
2046 		break;
2047 #endif /* WITH_OPENSSL */
2048 	case KEY_ED25519_CERT:
2049 		/* Skip nonce */
2050 		if (sshbuf_get_string_direct(b, NULL, NULL) != 0) {
2051 			ret = SSH_ERR_INVALID_FORMAT;
2052 			goto out;
2053 		}
2054 		/* FALLTHROUGH */
2055 	case KEY_ED25519:
2056 		if ((ret = sshbuf_get_string(b, &pk, &len)) != 0)
2057 			goto out;
2058 		if (len != ED25519_PK_SZ) {
2059 			ret = SSH_ERR_INVALID_FORMAT;
2060 			goto out;
2061 		}
2062 		if ((key = sshkey_new(type)) == NULL) {
2063 			ret = SSH_ERR_ALLOC_FAIL;
2064 			goto out;
2065 		}
2066 		key->ed25519_pk = pk;
2067 		pk = NULL;
2068 		break;
2069 	case KEY_UNSPEC:
2070 		if ((key = sshkey_new(type)) == NULL) {
2071 			ret = SSH_ERR_ALLOC_FAIL;
2072 			goto out;
2073 		}
2074 		break;
2075 	default:
2076 		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
2077 		goto out;
2078 	}
2079 
2080 	/* Parse certificate potion */
2081 	if (sshkey_is_cert(key) && (ret = cert_parse(b, key, copy)) != 0)
2082 		goto out;
2083 
2084 	if (key != NULL && sshbuf_len(b) != 0) {
2085 		ret = SSH_ERR_INVALID_FORMAT;
2086 		goto out;
2087 	}
2088 	ret = 0;
2089 	*keyp = key;
2090 	key = NULL;
2091  out:
2092 	sshbuf_free(copy);
2093 	sshkey_free(key);
2094 	free(ktype);
2095 	free(curve);
2096 	free(pk);
2097 #ifdef WITH_OPENSSL
2098 	if (q != NULL)
2099 		EC_POINT_free(q);
2100 #endif /* WITH_OPENSSL */
2101 	return ret;
2102 }
2103 
2104 int
2105 sshkey_from_blob(const u_char *blob, size_t blen, struct sshkey **keyp)
2106 {
2107 	struct sshbuf *b;
2108 	int r;
2109 
2110 	if ((b = sshbuf_from(blob, blen)) == NULL)
2111 		return SSH_ERR_ALLOC_FAIL;
2112 	r = sshkey_from_blob_internal(b, keyp, 1);
2113 	sshbuf_free(b);
2114 	return r;
2115 }
2116 
2117 int
2118 sshkey_fromb(struct sshbuf *b, struct sshkey **keyp)
2119 {
2120 	return sshkey_from_blob_internal(b, keyp, 1);
2121 }
2122 
2123 int
2124 sshkey_froms(struct sshbuf *buf, struct sshkey **keyp)
2125 {
2126 	struct sshbuf *b;
2127 	int r;
2128 
2129 	if ((r = sshbuf_froms(buf, &b)) != 0)
2130 		return r;
2131 	r = sshkey_from_blob_internal(b, keyp, 1);
2132 	sshbuf_free(b);
2133 	return r;
2134 }
2135 
2136 int
2137 sshkey_sign(const struct sshkey *key,
2138     u_char **sigp, size_t *lenp,
2139     const u_char *data, size_t datalen, u_int compat)
2140 {
2141 	if (sigp != NULL)
2142 		*sigp = NULL;
2143 	if (lenp != NULL)
2144 		*lenp = 0;
2145 	if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2146 		return SSH_ERR_INVALID_ARGUMENT;
2147 	switch (key->type) {
2148 #ifdef WITH_OPENSSL
2149 	case KEY_DSA_CERT:
2150 	case KEY_DSA:
2151 		return ssh_dss_sign(key, sigp, lenp, data, datalen, compat);
2152 	case KEY_ECDSA_CERT:
2153 	case KEY_ECDSA:
2154 		return ssh_ecdsa_sign(key, sigp, lenp, data, datalen, compat);
2155 	case KEY_RSA_CERT:
2156 	case KEY_RSA:
2157 		return ssh_rsa_sign(key, sigp, lenp, data, datalen, compat);
2158 #endif /* WITH_OPENSSL */
2159 	case KEY_ED25519:
2160 	case KEY_ED25519_CERT:
2161 		return ssh_ed25519_sign(key, sigp, lenp, data, datalen, compat);
2162 	default:
2163 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2164 	}
2165 }
2166 
2167 /*
2168  * ssh_key_verify returns 0 for a correct signature  and < 0 on error.
2169  */
2170 int
2171 sshkey_verify(const struct sshkey *key,
2172     const u_char *sig, size_t siglen,
2173     const u_char *data, size_t dlen, u_int compat)
2174 {
2175 	if (siglen == 0 || dlen > SSH_KEY_MAX_SIGN_DATA_SIZE)
2176 		return SSH_ERR_INVALID_ARGUMENT;
2177 	switch (key->type) {
2178 #ifdef WITH_OPENSSL
2179 	case KEY_DSA_CERT:
2180 	case KEY_DSA:
2181 		return ssh_dss_verify(key, sig, siglen, data, dlen, compat);
2182 	case KEY_ECDSA_CERT:
2183 	case KEY_ECDSA:
2184 		return ssh_ecdsa_verify(key, sig, siglen, data, dlen, compat);
2185 	case KEY_RSA_CERT:
2186 	case KEY_RSA:
2187 		return ssh_rsa_verify(key, sig, siglen, data, dlen, compat);
2188 #endif /* WITH_OPENSSL */
2189 	case KEY_ED25519:
2190 	case KEY_ED25519_CERT:
2191 		return ssh_ed25519_verify(key, sig, siglen, data, dlen, compat);
2192 	default:
2193 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2194 	}
2195 }
2196 
2197 /* Converts a private to a public key */
2198 int
2199 sshkey_demote(const struct sshkey *k, struct sshkey **dkp)
2200 {
2201 	struct sshkey *pk;
2202 	int ret = SSH_ERR_INTERNAL_ERROR;
2203 
2204 	if (dkp != NULL)
2205 		*dkp = NULL;
2206 
2207 	if ((pk = calloc(1, sizeof(*pk))) == NULL)
2208 		return SSH_ERR_ALLOC_FAIL;
2209 	pk->type = k->type;
2210 	pk->flags = k->flags;
2211 	pk->ecdsa_nid = k->ecdsa_nid;
2212 	pk->dsa = NULL;
2213 	pk->ecdsa = NULL;
2214 	pk->rsa = NULL;
2215 	pk->ed25519_pk = NULL;
2216 	pk->ed25519_sk = NULL;
2217 
2218 	switch (k->type) {
2219 #ifdef WITH_OPENSSL
2220 	case KEY_RSA_CERT:
2221 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2222 			goto fail;
2223 		/* FALLTHROUGH */
2224 	case KEY_RSA1:
2225 	case KEY_RSA:
2226 		if ((pk->rsa = RSA_new()) == NULL ||
2227 		    (pk->rsa->e = BN_dup(k->rsa->e)) == NULL ||
2228 		    (pk->rsa->n = BN_dup(k->rsa->n)) == NULL) {
2229 			ret = SSH_ERR_ALLOC_FAIL;
2230 			goto fail;
2231 			}
2232 		break;
2233 	case KEY_DSA_CERT:
2234 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2235 			goto fail;
2236 		/* FALLTHROUGH */
2237 	case KEY_DSA:
2238 		if ((pk->dsa = DSA_new()) == NULL ||
2239 		    (pk->dsa->p = BN_dup(k->dsa->p)) == NULL ||
2240 		    (pk->dsa->q = BN_dup(k->dsa->q)) == NULL ||
2241 		    (pk->dsa->g = BN_dup(k->dsa->g)) == NULL ||
2242 		    (pk->dsa->pub_key = BN_dup(k->dsa->pub_key)) == NULL) {
2243 			ret = SSH_ERR_ALLOC_FAIL;
2244 			goto fail;
2245 		}
2246 		break;
2247 	case KEY_ECDSA_CERT:
2248 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2249 			goto fail;
2250 		/* FALLTHROUGH */
2251 	case KEY_ECDSA:
2252 		pk->ecdsa = EC_KEY_new_by_curve_name(pk->ecdsa_nid);
2253 		if (pk->ecdsa == NULL) {
2254 			ret = SSH_ERR_ALLOC_FAIL;
2255 			goto fail;
2256 		}
2257 		if (EC_KEY_set_public_key(pk->ecdsa,
2258 		    EC_KEY_get0_public_key(k->ecdsa)) != 1) {
2259 			ret = SSH_ERR_LIBCRYPTO_ERROR;
2260 			goto fail;
2261 		}
2262 		break;
2263 #endif /* WITH_OPENSSL */
2264 	case KEY_ED25519_CERT:
2265 		if ((ret = sshkey_cert_copy(k, pk)) != 0)
2266 			goto fail;
2267 		/* FALLTHROUGH */
2268 	case KEY_ED25519:
2269 		if (k->ed25519_pk != NULL) {
2270 			if ((pk->ed25519_pk = malloc(ED25519_PK_SZ)) == NULL) {
2271 				ret = SSH_ERR_ALLOC_FAIL;
2272 				goto fail;
2273 			}
2274 			memcpy(pk->ed25519_pk, k->ed25519_pk, ED25519_PK_SZ);
2275 		}
2276 		break;
2277 	default:
2278 		ret = SSH_ERR_KEY_TYPE_UNKNOWN;
2279  fail:
2280 		sshkey_free(pk);
2281 		return ret;
2282 	}
2283 	*dkp = pk;
2284 	return 0;
2285 }
2286 
2287 /* Convert a plain key to their _CERT equivalent */
2288 int
2289 sshkey_to_certified(struct sshkey *k)
2290 {
2291 	int newtype;
2292 
2293 	switch (k->type) {
2294 #ifdef WITH_OPENSSL
2295 	case KEY_RSA:
2296 		newtype = KEY_RSA_CERT;
2297 		break;
2298 	case KEY_DSA:
2299 		newtype = KEY_DSA_CERT;
2300 		break;
2301 	case KEY_ECDSA:
2302 		newtype = KEY_ECDSA_CERT;
2303 		break;
2304 #endif /* WITH_OPENSSL */
2305 	case KEY_ED25519:
2306 		newtype = KEY_ED25519_CERT;
2307 		break;
2308 	default:
2309 		return SSH_ERR_INVALID_ARGUMENT;
2310 	}
2311 	if ((k->cert = cert_new()) == NULL)
2312 		return SSH_ERR_ALLOC_FAIL;
2313 	k->type = newtype;
2314 	return 0;
2315 }
2316 
2317 /* Convert a certificate to its raw key equivalent */
2318 int
2319 sshkey_drop_cert(struct sshkey *k)
2320 {
2321 	if (!sshkey_type_is_cert(k->type))
2322 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2323 	cert_free(k->cert);
2324 	k->cert = NULL;
2325 	k->type = sshkey_type_plain(k->type);
2326 	return 0;
2327 }
2328 
2329 /* Sign a certified key, (re-)generating the signed certblob. */
2330 int
2331 sshkey_certify(struct sshkey *k, struct sshkey *ca)
2332 {
2333 	struct sshbuf *principals = NULL;
2334 	u_char *ca_blob = NULL, *sig_blob = NULL, nonce[32];
2335 	size_t i, ca_len, sig_len;
2336 	int ret = SSH_ERR_INTERNAL_ERROR;
2337 	struct sshbuf *cert;
2338 
2339 	if (k == NULL || k->cert == NULL ||
2340 	    k->cert->certblob == NULL || ca == NULL)
2341 		return SSH_ERR_INVALID_ARGUMENT;
2342 	if (!sshkey_is_cert(k))
2343 		return SSH_ERR_KEY_TYPE_UNKNOWN;
2344 	if (!sshkey_type_is_valid_ca(ca->type))
2345 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2346 
2347 	if ((ret = sshkey_to_blob(ca, &ca_blob, &ca_len)) != 0)
2348 		return SSH_ERR_KEY_CERT_INVALID_SIGN_KEY;
2349 
2350 	cert = k->cert->certblob; /* for readability */
2351 	sshbuf_reset(cert);
2352 	if ((ret = sshbuf_put_cstring(cert, sshkey_ssh_name(k))) != 0)
2353 		goto out;
2354 
2355 	/* -v01 certs put nonce first */
2356 	arc4random_buf(&nonce, sizeof(nonce));
2357 	if ((ret = sshbuf_put_string(cert, nonce, sizeof(nonce))) != 0)
2358 		goto out;
2359 
2360 	/* XXX this substantially duplicates to_blob(); refactor */
2361 	switch (k->type) {
2362 #ifdef WITH_OPENSSL
2363 	case KEY_DSA_CERT:
2364 		if ((ret = sshbuf_put_bignum2(cert, k->dsa->p)) != 0 ||
2365 		    (ret = sshbuf_put_bignum2(cert, k->dsa->q)) != 0 ||
2366 		    (ret = sshbuf_put_bignum2(cert, k->dsa->g)) != 0 ||
2367 		    (ret = sshbuf_put_bignum2(cert, k->dsa->pub_key)) != 0)
2368 			goto out;
2369 		break;
2370 	case KEY_ECDSA_CERT:
2371 		if ((ret = sshbuf_put_cstring(cert,
2372 		    sshkey_curve_nid_to_name(k->ecdsa_nid))) != 0 ||
2373 		    (ret = sshbuf_put_ec(cert,
2374 		    EC_KEY_get0_public_key(k->ecdsa),
2375 		    EC_KEY_get0_group(k->ecdsa))) != 0)
2376 			goto out;
2377 		break;
2378 	case KEY_RSA_CERT:
2379 		if ((ret = sshbuf_put_bignum2(cert, k->rsa->e)) != 0 ||
2380 		    (ret = sshbuf_put_bignum2(cert, k->rsa->n)) != 0)
2381 			goto out;
2382 		break;
2383 #endif /* WITH_OPENSSL */
2384 	case KEY_ED25519_CERT:
2385 		if ((ret = sshbuf_put_string(cert,
2386 		    k->ed25519_pk, ED25519_PK_SZ)) != 0)
2387 			goto out;
2388 		break;
2389 	default:
2390 		ret = SSH_ERR_INVALID_ARGUMENT;
2391 		goto out;
2392 	}
2393 
2394 	if ((ret = sshbuf_put_u64(cert, k->cert->serial)) != 0 ||
2395 	    (ret = sshbuf_put_u32(cert, k->cert->type)) != 0 ||
2396 	    (ret = sshbuf_put_cstring(cert, k->cert->key_id)) != 0)
2397 		goto out;
2398 
2399 	if ((principals = sshbuf_new()) == NULL) {
2400 		ret = SSH_ERR_ALLOC_FAIL;
2401 		goto out;
2402 	}
2403 	for (i = 0; i < k->cert->nprincipals; i++) {
2404 		if ((ret = sshbuf_put_cstring(principals,
2405 		    k->cert->principals[i])) != 0)
2406 			goto out;
2407 	}
2408 	if ((ret = sshbuf_put_stringb(cert, principals)) != 0 ||
2409 	    (ret = sshbuf_put_u64(cert, k->cert->valid_after)) != 0 ||
2410 	    (ret = sshbuf_put_u64(cert, k->cert->valid_before)) != 0 ||
2411 	    (ret = sshbuf_put_stringb(cert, k->cert->critical)) != 0 ||
2412 	    (ret = sshbuf_put_stringb(cert, k->cert->extensions)) != 0 ||
2413 	    (ret = sshbuf_put_string(cert, NULL, 0)) != 0 || /* Reserved */
2414 	    (ret = sshbuf_put_string(cert, ca_blob, ca_len)) != 0)
2415 		goto out;
2416 
2417 	/* Sign the whole mess */
2418 	if ((ret = sshkey_sign(ca, &sig_blob, &sig_len, sshbuf_ptr(cert),
2419 	    sshbuf_len(cert), 0)) != 0)
2420 		goto out;
2421 
2422 	/* Append signature and we are done */
2423 	if ((ret = sshbuf_put_string(cert, sig_blob, sig_len)) != 0)
2424 		goto out;
2425 	ret = 0;
2426  out:
2427 	if (ret != 0)
2428 		sshbuf_reset(cert);
2429 	if (sig_blob != NULL)
2430 		free(sig_blob);
2431 	if (ca_blob != NULL)
2432 		free(ca_blob);
2433 	if (principals != NULL)
2434 		sshbuf_free(principals);
2435 	return ret;
2436 }
2437 
2438 int
2439 sshkey_cert_check_authority(const struct sshkey *k,
2440     int want_host, int require_principal,
2441     const char *name, const char **reason)
2442 {
2443 	u_int i, principal_matches;
2444 	time_t now = time(NULL);
2445 
2446 	if (reason != NULL)
2447 		*reason = NULL;
2448 
2449 	if (want_host) {
2450 		if (k->cert->type != SSH2_CERT_TYPE_HOST) {
2451 			*reason = "Certificate invalid: not a host certificate";
2452 			return SSH_ERR_KEY_CERT_INVALID;
2453 		}
2454 	} else {
2455 		if (k->cert->type != SSH2_CERT_TYPE_USER) {
2456 			*reason = "Certificate invalid: not a user certificate";
2457 			return SSH_ERR_KEY_CERT_INVALID;
2458 		}
2459 	}
2460 	if (now < 0) {
2461 		/* yikes - system clock before epoch! */
2462 		*reason = "Certificate invalid: not yet valid";
2463 		return SSH_ERR_KEY_CERT_INVALID;
2464 	}
2465 	if ((u_int64_t)now < k->cert->valid_after) {
2466 		*reason = "Certificate invalid: not yet valid";
2467 		return SSH_ERR_KEY_CERT_INVALID;
2468 	}
2469 	if ((u_int64_t)now >= k->cert->valid_before) {
2470 		*reason = "Certificate invalid: expired";
2471 		return SSH_ERR_KEY_CERT_INVALID;
2472 	}
2473 	if (k->cert->nprincipals == 0) {
2474 		if (require_principal) {
2475 			*reason = "Certificate lacks principal list";
2476 			return SSH_ERR_KEY_CERT_INVALID;
2477 		}
2478 	} else if (name != NULL) {
2479 		principal_matches = 0;
2480 		for (i = 0; i < k->cert->nprincipals; i++) {
2481 			if (strcmp(name, k->cert->principals[i]) == 0) {
2482 				principal_matches = 1;
2483 				break;
2484 			}
2485 		}
2486 		if (!principal_matches) {
2487 			*reason = "Certificate invalid: name is not a listed "
2488 			    "principal";
2489 			return SSH_ERR_KEY_CERT_INVALID;
2490 		}
2491 	}
2492 	return 0;
2493 }
2494 
2495 int
2496 sshkey_private_serialize(const struct sshkey *key, struct sshbuf *b)
2497 {
2498 	int r = SSH_ERR_INTERNAL_ERROR;
2499 
2500 	if ((r = sshbuf_put_cstring(b, sshkey_ssh_name(key))) != 0)
2501 		goto out;
2502 	switch (key->type) {
2503 #ifdef WITH_OPENSSL
2504 	case KEY_RSA:
2505 		if ((r = sshbuf_put_bignum2(b, key->rsa->n)) != 0 ||
2506 		    (r = sshbuf_put_bignum2(b, key->rsa->e)) != 0 ||
2507 		    (r = sshbuf_put_bignum2(b, key->rsa->d)) != 0 ||
2508 		    (r = sshbuf_put_bignum2(b, key->rsa->iqmp)) != 0 ||
2509 		    (r = sshbuf_put_bignum2(b, key->rsa->p)) != 0 ||
2510 		    (r = sshbuf_put_bignum2(b, key->rsa->q)) != 0)
2511 			goto out;
2512 		break;
2513 	case KEY_RSA_CERT:
2514 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2515 			r = SSH_ERR_INVALID_ARGUMENT;
2516 			goto out;
2517 		}
2518 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2519 		    (r = sshbuf_put_bignum2(b, key->rsa->d)) != 0 ||
2520 		    (r = sshbuf_put_bignum2(b, key->rsa->iqmp)) != 0 ||
2521 		    (r = sshbuf_put_bignum2(b, key->rsa->p)) != 0 ||
2522 		    (r = sshbuf_put_bignum2(b, key->rsa->q)) != 0)
2523 			goto out;
2524 		break;
2525 	case KEY_DSA:
2526 		if ((r = sshbuf_put_bignum2(b, key->dsa->p)) != 0 ||
2527 		    (r = sshbuf_put_bignum2(b, key->dsa->q)) != 0 ||
2528 		    (r = sshbuf_put_bignum2(b, key->dsa->g)) != 0 ||
2529 		    (r = sshbuf_put_bignum2(b, key->dsa->pub_key)) != 0 ||
2530 		    (r = sshbuf_put_bignum2(b, key->dsa->priv_key)) != 0)
2531 			goto out;
2532 		break;
2533 	case KEY_DSA_CERT:
2534 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2535 			r = SSH_ERR_INVALID_ARGUMENT;
2536 			goto out;
2537 		}
2538 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2539 		    (r = sshbuf_put_bignum2(b, key->dsa->priv_key)) != 0)
2540 			goto out;
2541 		break;
2542 	case KEY_ECDSA:
2543 		if ((r = sshbuf_put_cstring(b,
2544 		    sshkey_curve_nid_to_name(key->ecdsa_nid))) != 0 ||
2545 		    (r = sshbuf_put_eckey(b, key->ecdsa)) != 0 ||
2546 		    (r = sshbuf_put_bignum2(b,
2547 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
2548 			goto out;
2549 		break;
2550 	case KEY_ECDSA_CERT:
2551 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2552 			r = SSH_ERR_INVALID_ARGUMENT;
2553 			goto out;
2554 		}
2555 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2556 		    (r = sshbuf_put_bignum2(b,
2557 		    EC_KEY_get0_private_key(key->ecdsa))) != 0)
2558 			goto out;
2559 		break;
2560 #endif /* WITH_OPENSSL */
2561 	case KEY_ED25519:
2562 		if ((r = sshbuf_put_string(b, key->ed25519_pk,
2563 		    ED25519_PK_SZ)) != 0 ||
2564 		    (r = sshbuf_put_string(b, key->ed25519_sk,
2565 		    ED25519_SK_SZ)) != 0)
2566 			goto out;
2567 		break;
2568 	case KEY_ED25519_CERT:
2569 		if (key->cert == NULL || sshbuf_len(key->cert->certblob) == 0) {
2570 			r = SSH_ERR_INVALID_ARGUMENT;
2571 			goto out;
2572 		}
2573 		if ((r = sshbuf_put_stringb(b, key->cert->certblob)) != 0 ||
2574 		    (r = sshbuf_put_string(b, key->ed25519_pk,
2575 		    ED25519_PK_SZ)) != 0 ||
2576 		    (r = sshbuf_put_string(b, key->ed25519_sk,
2577 		    ED25519_SK_SZ)) != 0)
2578 			goto out;
2579 		break;
2580 	default:
2581 		r = SSH_ERR_INVALID_ARGUMENT;
2582 		goto out;
2583 	}
2584 	/* success */
2585 	r = 0;
2586  out:
2587 	return r;
2588 }
2589 
2590 int
2591 sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **kp)
2592 {
2593 	char *tname = NULL, *curve = NULL;
2594 	struct sshkey *k = NULL;
2595 	size_t pklen = 0, sklen = 0;
2596 	int type, r = SSH_ERR_INTERNAL_ERROR;
2597 	u_char *ed25519_pk = NULL, *ed25519_sk = NULL;
2598 #ifdef WITH_OPENSSL
2599 	BIGNUM *exponent = NULL;
2600 #endif /* WITH_OPENSSL */
2601 
2602 	if (kp != NULL)
2603 		*kp = NULL;
2604 	if ((r = sshbuf_get_cstring(buf, &tname, NULL)) != 0)
2605 		goto out;
2606 	type = sshkey_type_from_name(tname);
2607 	switch (type) {
2608 #ifdef WITH_OPENSSL
2609 	case KEY_DSA:
2610 		if ((k = sshkey_new_private(type)) == NULL) {
2611 			r = SSH_ERR_ALLOC_FAIL;
2612 			goto out;
2613 		}
2614 		if ((r = sshbuf_get_bignum2(buf, k->dsa->p)) != 0 ||
2615 		    (r = sshbuf_get_bignum2(buf, k->dsa->q)) != 0 ||
2616 		    (r = sshbuf_get_bignum2(buf, k->dsa->g)) != 0 ||
2617 		    (r = sshbuf_get_bignum2(buf, k->dsa->pub_key)) != 0 ||
2618 		    (r = sshbuf_get_bignum2(buf, k->dsa->priv_key)) != 0)
2619 			goto out;
2620 		break;
2621 	case KEY_DSA_CERT:
2622 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2623 		    (r = sshkey_add_private(k)) != 0 ||
2624 		    (r = sshbuf_get_bignum2(buf, k->dsa->priv_key)) != 0)
2625 			goto out;
2626 		break;
2627 	case KEY_ECDSA:
2628 		if ((k = sshkey_new_private(type)) == NULL) {
2629 			r = SSH_ERR_ALLOC_FAIL;
2630 			goto out;
2631 		}
2632 		if ((k->ecdsa_nid = sshkey_ecdsa_nid_from_name(tname)) == -1) {
2633 			r = SSH_ERR_INVALID_ARGUMENT;
2634 			goto out;
2635 		}
2636 		if ((r = sshbuf_get_cstring(buf, &curve, NULL)) != 0)
2637 			goto out;
2638 		if (k->ecdsa_nid != sshkey_curve_name_to_nid(curve)) {
2639 			r = SSH_ERR_EC_CURVE_MISMATCH;
2640 			goto out;
2641 		}
2642 		k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
2643 		if (k->ecdsa  == NULL || (exponent = BN_new()) == NULL) {
2644 			r = SSH_ERR_LIBCRYPTO_ERROR;
2645 			goto out;
2646 		}
2647 		if ((r = sshbuf_get_eckey(buf, k->ecdsa)) != 0 ||
2648 		    (r = sshbuf_get_bignum2(buf, exponent)))
2649 			goto out;
2650 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
2651 			r = SSH_ERR_LIBCRYPTO_ERROR;
2652 			goto out;
2653 		}
2654 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
2655 		    EC_KEY_get0_public_key(k->ecdsa)) != 0) ||
2656 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
2657 			goto out;
2658 		break;
2659 	case KEY_ECDSA_CERT:
2660 		if ((exponent = BN_new()) == NULL) {
2661 			r = SSH_ERR_LIBCRYPTO_ERROR;
2662 			goto out;
2663 		}
2664 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2665 		    (r = sshkey_add_private(k)) != 0 ||
2666 		    (r = sshbuf_get_bignum2(buf, exponent)) != 0)
2667 			goto out;
2668 		if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) {
2669 			r = SSH_ERR_LIBCRYPTO_ERROR;
2670 			goto out;
2671 		}
2672 		if ((r = sshkey_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
2673 		    EC_KEY_get0_public_key(k->ecdsa)) != 0) ||
2674 		    (r = sshkey_ec_validate_private(k->ecdsa)) != 0)
2675 			goto out;
2676 		break;
2677 	case KEY_RSA:
2678 		if ((k = sshkey_new_private(type)) == NULL) {
2679 			r = SSH_ERR_ALLOC_FAIL;
2680 			goto out;
2681 		}
2682 		if ((r = sshbuf_get_bignum2(buf, k->rsa->n)) != 0 ||
2683 		    (r = sshbuf_get_bignum2(buf, k->rsa->e)) != 0 ||
2684 		    (r = sshbuf_get_bignum2(buf, k->rsa->d)) != 0 ||
2685 		    (r = sshbuf_get_bignum2(buf, k->rsa->iqmp)) != 0 ||
2686 		    (r = sshbuf_get_bignum2(buf, k->rsa->p)) != 0 ||
2687 		    (r = sshbuf_get_bignum2(buf, k->rsa->q)) != 0 ||
2688 		    (r = rsa_generate_additional_parameters(k->rsa)) != 0)
2689 			goto out;
2690 		break;
2691 	case KEY_RSA_CERT:
2692 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2693 		    (r = sshkey_add_private(k)) != 0 ||
2694 		    (r = sshbuf_get_bignum2(buf, k->rsa->d) != 0) ||
2695 		    (r = sshbuf_get_bignum2(buf, k->rsa->iqmp) != 0) ||
2696 		    (r = sshbuf_get_bignum2(buf, k->rsa->p) != 0) ||
2697 		    (r = sshbuf_get_bignum2(buf, k->rsa->q) != 0) ||
2698 		    (r = rsa_generate_additional_parameters(k->rsa)) != 0)
2699 			goto out;
2700 		break;
2701 #endif /* WITH_OPENSSL */
2702 	case KEY_ED25519:
2703 		if ((k = sshkey_new_private(type)) == NULL) {
2704 			r = SSH_ERR_ALLOC_FAIL;
2705 			goto out;
2706 		}
2707 		if ((r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
2708 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
2709 			goto out;
2710 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
2711 			r = SSH_ERR_INVALID_FORMAT;
2712 			goto out;
2713 		}
2714 		k->ed25519_pk = ed25519_pk;
2715 		k->ed25519_sk = ed25519_sk;
2716 		ed25519_pk = ed25519_sk = NULL;
2717 		break;
2718 	case KEY_ED25519_CERT:
2719 		if ((r = sshkey_froms(buf, &k)) != 0 ||
2720 		    (r = sshkey_add_private(k)) != 0 ||
2721 		    (r = sshbuf_get_string(buf, &ed25519_pk, &pklen)) != 0 ||
2722 		    (r = sshbuf_get_string(buf, &ed25519_sk, &sklen)) != 0)
2723 			goto out;
2724 		if (pklen != ED25519_PK_SZ || sklen != ED25519_SK_SZ) {
2725 			r = SSH_ERR_INVALID_FORMAT;
2726 			goto out;
2727 		}
2728 		k->ed25519_pk = ed25519_pk;
2729 		k->ed25519_sk = ed25519_sk;
2730 		ed25519_pk = ed25519_sk = NULL;
2731 		break;
2732 	default:
2733 		r = SSH_ERR_KEY_TYPE_UNKNOWN;
2734 		goto out;
2735 	}
2736 #ifdef WITH_OPENSSL
2737 	/* enable blinding */
2738 	switch (k->type) {
2739 	case KEY_RSA:
2740 	case KEY_RSA_CERT:
2741 	case KEY_RSA1:
2742 		if (RSA_blinding_on(k->rsa, NULL) != 1) {
2743 			r = SSH_ERR_LIBCRYPTO_ERROR;
2744 			goto out;
2745 		}
2746 		break;
2747 	}
2748 #endif /* WITH_OPENSSL */
2749 	/* success */
2750 	r = 0;
2751 	if (kp != NULL) {
2752 		*kp = k;
2753 		k = NULL;
2754 	}
2755  out:
2756 	free(tname);
2757 	free(curve);
2758 #ifdef WITH_OPENSSL
2759 	if (exponent != NULL)
2760 		BN_clear_free(exponent);
2761 #endif /* WITH_OPENSSL */
2762 	sshkey_free(k);
2763 	if (ed25519_pk != NULL) {
2764 		explicit_bzero(ed25519_pk, pklen);
2765 		free(ed25519_pk);
2766 	}
2767 	if (ed25519_sk != NULL) {
2768 		explicit_bzero(ed25519_sk, sklen);
2769 		free(ed25519_sk);
2770 	}
2771 	return r;
2772 }
2773 
2774 #ifdef WITH_OPENSSL
2775 int
2776 sshkey_ec_validate_public(const EC_GROUP *group, const EC_POINT *public)
2777 {
2778 	BN_CTX *bnctx;
2779 	EC_POINT *nq = NULL;
2780 	BIGNUM *order, *x, *y, *tmp;
2781 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2782 
2783 	if ((bnctx = BN_CTX_new()) == NULL)
2784 		return SSH_ERR_ALLOC_FAIL;
2785 	BN_CTX_start(bnctx);
2786 
2787 	/*
2788 	 * We shouldn't ever hit this case because bignum_get_ecpoint()
2789 	 * refuses to load GF2m points.
2790 	 */
2791 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2792 	    NID_X9_62_prime_field)
2793 		goto out;
2794 
2795 	/* Q != infinity */
2796 	if (EC_POINT_is_at_infinity(group, public))
2797 		goto out;
2798 
2799 	if ((x = BN_CTX_get(bnctx)) == NULL ||
2800 	    (y = BN_CTX_get(bnctx)) == NULL ||
2801 	    (order = BN_CTX_get(bnctx)) == NULL ||
2802 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
2803 		ret = SSH_ERR_ALLOC_FAIL;
2804 		goto out;
2805 	}
2806 
2807 	/* log2(x) > log2(order)/2, log2(y) > log2(order)/2 */
2808 	if (EC_GROUP_get_order(group, order, bnctx) != 1 ||
2809 	    EC_POINT_get_affine_coordinates_GFp(group, public,
2810 	    x, y, bnctx) != 1) {
2811 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2812 		goto out;
2813 	}
2814 	if (BN_num_bits(x) <= BN_num_bits(order) / 2 ||
2815 	    BN_num_bits(y) <= BN_num_bits(order) / 2)
2816 		goto out;
2817 
2818 	/* nQ == infinity (n == order of subgroup) */
2819 	if ((nq = EC_POINT_new(group)) == NULL) {
2820 		ret = SSH_ERR_ALLOC_FAIL;
2821 		goto out;
2822 	}
2823 	if (EC_POINT_mul(group, nq, NULL, public, order, bnctx) != 1) {
2824 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2825 		goto out;
2826 	}
2827 	if (EC_POINT_is_at_infinity(group, nq) != 1)
2828 		goto out;
2829 
2830 	/* x < order - 1, y < order - 1 */
2831 	if (!BN_sub(tmp, order, BN_value_one())) {
2832 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2833 		goto out;
2834 	}
2835 	if (BN_cmp(x, tmp) >= 0 || BN_cmp(y, tmp) >= 0)
2836 		goto out;
2837 	ret = 0;
2838  out:
2839 	BN_CTX_free(bnctx);
2840 	if (nq != NULL)
2841 		EC_POINT_free(nq);
2842 	return ret;
2843 }
2844 
2845 int
2846 sshkey_ec_validate_private(const EC_KEY *key)
2847 {
2848 	BN_CTX *bnctx;
2849 	BIGNUM *order, *tmp;
2850 	int ret = SSH_ERR_KEY_INVALID_EC_VALUE;
2851 
2852 	if ((bnctx = BN_CTX_new()) == NULL)
2853 		return SSH_ERR_ALLOC_FAIL;
2854 	BN_CTX_start(bnctx);
2855 
2856 	if ((order = BN_CTX_get(bnctx)) == NULL ||
2857 	    (tmp = BN_CTX_get(bnctx)) == NULL) {
2858 		ret = SSH_ERR_ALLOC_FAIL;
2859 		goto out;
2860 	}
2861 
2862 	/* log2(private) > log2(order)/2 */
2863 	if (EC_GROUP_get_order(EC_KEY_get0_group(key), order, bnctx) != 1) {
2864 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2865 		goto out;
2866 	}
2867 	if (BN_num_bits(EC_KEY_get0_private_key(key)) <=
2868 	    BN_num_bits(order) / 2)
2869 		goto out;
2870 
2871 	/* private < order - 1 */
2872 	if (!BN_sub(tmp, order, BN_value_one())) {
2873 		ret = SSH_ERR_LIBCRYPTO_ERROR;
2874 		goto out;
2875 	}
2876 	if (BN_cmp(EC_KEY_get0_private_key(key), tmp) >= 0)
2877 		goto out;
2878 	ret = 0;
2879  out:
2880 	BN_CTX_free(bnctx);
2881 	return ret;
2882 }
2883 
2884 void
2885 sshkey_dump_ec_point(const EC_GROUP *group, const EC_POINT *point)
2886 {
2887 	BIGNUM *x, *y;
2888 	BN_CTX *bnctx;
2889 
2890 	if (point == NULL) {
2891 		fputs("point=(NULL)\n", stderr);
2892 		return;
2893 	}
2894 	if ((bnctx = BN_CTX_new()) == NULL) {
2895 		fprintf(stderr, "%s: BN_CTX_new failed\n", __func__);
2896 		return;
2897 	}
2898 	BN_CTX_start(bnctx);
2899 	if ((x = BN_CTX_get(bnctx)) == NULL ||
2900 	    (y = BN_CTX_get(bnctx)) == NULL) {
2901 		fprintf(stderr, "%s: BN_CTX_get failed\n", __func__);
2902 		return;
2903 	}
2904 	if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) !=
2905 	    NID_X9_62_prime_field) {
2906 		fprintf(stderr, "%s: group is not a prime field\n", __func__);
2907 		return;
2908 	}
2909 	if (EC_POINT_get_affine_coordinates_GFp(group, point, x, y,
2910 	    bnctx) != 1) {
2911 		fprintf(stderr, "%s: EC_POINT_get_affine_coordinates_GFp\n",
2912 		    __func__);
2913 		return;
2914 	}
2915 	fputs("x=", stderr);
2916 	BN_print_fp(stderr, x);
2917 	fputs("\ny=", stderr);
2918 	BN_print_fp(stderr, y);
2919 	fputs("\n", stderr);
2920 	BN_CTX_free(bnctx);
2921 }
2922 
2923 void
2924 sshkey_dump_ec_key(const EC_KEY *key)
2925 {
2926 	const BIGNUM *exponent;
2927 
2928 	sshkey_dump_ec_point(EC_KEY_get0_group(key),
2929 	    EC_KEY_get0_public_key(key));
2930 	fputs("exponent=", stderr);
2931 	if ((exponent = EC_KEY_get0_private_key(key)) == NULL)
2932 		fputs("(NULL)", stderr);
2933 	else
2934 		BN_print_fp(stderr, EC_KEY_get0_private_key(key));
2935 	fputs("\n", stderr);
2936 }
2937 #endif /* WITH_OPENSSL */
2938 
2939 static int
2940 sshkey_private_to_blob2(const struct sshkey *prv, struct sshbuf *blob,
2941     const char *passphrase, const char *comment, const char *ciphername,
2942     int rounds)
2943 {
2944 	u_char *cp, *key = NULL, *pubkeyblob = NULL;
2945 	u_char salt[SALT_LEN];
2946 	char *b64 = NULL;
2947 	size_t i, pubkeylen, keylen, ivlen, blocksize, authlen;
2948 	u_int check;
2949 	int r = SSH_ERR_INTERNAL_ERROR;
2950 	struct sshcipher_ctx ciphercontext;
2951 	const struct sshcipher *cipher;
2952 	const char *kdfname = KDFNAME;
2953 	struct sshbuf *encoded = NULL, *encrypted = NULL, *kdf = NULL;
2954 
2955 	memset(&ciphercontext, 0, sizeof(ciphercontext));
2956 
2957 	if (rounds <= 0)
2958 		rounds = DEFAULT_ROUNDS;
2959 	if (passphrase == NULL || !strlen(passphrase)) {
2960 		ciphername = "none";
2961 		kdfname = "none";
2962 	} else if (ciphername == NULL)
2963 		ciphername = DEFAULT_CIPHERNAME;
2964 	else if (cipher_number(ciphername) != SSH_CIPHER_SSH2) {
2965 		r = SSH_ERR_INVALID_ARGUMENT;
2966 		goto out;
2967 	}
2968 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
2969 		r = SSH_ERR_INTERNAL_ERROR;
2970 		goto out;
2971 	}
2972 
2973 	if ((kdf = sshbuf_new()) == NULL ||
2974 	    (encoded = sshbuf_new()) == NULL ||
2975 	    (encrypted = sshbuf_new()) == NULL) {
2976 		r = SSH_ERR_ALLOC_FAIL;
2977 		goto out;
2978 	}
2979 	blocksize = cipher_blocksize(cipher);
2980 	keylen = cipher_keylen(cipher);
2981 	ivlen = cipher_ivlen(cipher);
2982 	authlen = cipher_authlen(cipher);
2983 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
2984 		r = SSH_ERR_ALLOC_FAIL;
2985 		goto out;
2986 	}
2987 	if (strcmp(kdfname, "bcrypt") == 0) {
2988 		arc4random_buf(salt, SALT_LEN);
2989 		if (bcrypt_pbkdf(passphrase, strlen(passphrase),
2990 		    salt, SALT_LEN, key, keylen + ivlen, rounds) < 0) {
2991 			r = SSH_ERR_INVALID_ARGUMENT;
2992 			goto out;
2993 		}
2994 		if ((r = sshbuf_put_string(kdf, salt, SALT_LEN)) != 0 ||
2995 		    (r = sshbuf_put_u32(kdf, rounds)) != 0)
2996 			goto out;
2997 	} else if (strcmp(kdfname, "none") != 0) {
2998 		/* Unsupported KDF type */
2999 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3000 		goto out;
3001 	}
3002 	if ((r = cipher_init(&ciphercontext, cipher, key, keylen,
3003 	    key + keylen, ivlen, 1)) != 0)
3004 		goto out;
3005 
3006 	if ((r = sshbuf_put(encoded, AUTH_MAGIC, sizeof(AUTH_MAGIC))) != 0 ||
3007 	    (r = sshbuf_put_cstring(encoded, ciphername)) != 0 ||
3008 	    (r = sshbuf_put_cstring(encoded, kdfname)) != 0 ||
3009 	    (r = sshbuf_put_stringb(encoded, kdf)) != 0 ||
3010 	    (r = sshbuf_put_u32(encoded, 1)) != 0 ||	/* number of keys */
3011 	    (r = sshkey_to_blob(prv, &pubkeyblob, &pubkeylen)) != 0 ||
3012 	    (r = sshbuf_put_string(encoded, pubkeyblob, pubkeylen)) != 0)
3013 		goto out;
3014 
3015 	/* set up the buffer that will be encrypted */
3016 
3017 	/* Random check bytes */
3018 	check = arc4random();
3019 	if ((r = sshbuf_put_u32(encrypted, check)) != 0 ||
3020 	    (r = sshbuf_put_u32(encrypted, check)) != 0)
3021 		goto out;
3022 
3023 	/* append private key and comment*/
3024 	if ((r = sshkey_private_serialize(prv, encrypted)) != 0 ||
3025 	    (r = sshbuf_put_cstring(encrypted, comment)) != 0)
3026 		goto out;
3027 
3028 	/* padding */
3029 	i = 0;
3030 	while (sshbuf_len(encrypted) % blocksize) {
3031 		if ((r = sshbuf_put_u8(encrypted, ++i & 0xff)) != 0)
3032 			goto out;
3033 	}
3034 
3035 	/* length in destination buffer */
3036 	if ((r = sshbuf_put_u32(encoded, sshbuf_len(encrypted))) != 0)
3037 		goto out;
3038 
3039 	/* encrypt */
3040 	if ((r = sshbuf_reserve(encoded,
3041 	    sshbuf_len(encrypted) + authlen, &cp)) != 0)
3042 		goto out;
3043 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3044 	    sshbuf_ptr(encrypted), sshbuf_len(encrypted), 0, authlen)) != 0)
3045 		goto out;
3046 
3047 	/* uuencode */
3048 	if ((b64 = sshbuf_dtob64(encoded)) == NULL) {
3049 		r = SSH_ERR_ALLOC_FAIL;
3050 		goto out;
3051 	}
3052 
3053 	sshbuf_reset(blob);
3054 	if ((r = sshbuf_put(blob, MARK_BEGIN, MARK_BEGIN_LEN)) != 0)
3055 		goto out;
3056 	for (i = 0; i < strlen(b64); i++) {
3057 		if ((r = sshbuf_put_u8(blob, b64[i])) != 0)
3058 			goto out;
3059 		/* insert line breaks */
3060 		if (i % 70 == 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3061 			goto out;
3062 	}
3063 	if (i % 70 != 69 && (r = sshbuf_put_u8(blob, '\n')) != 0)
3064 		goto out;
3065 	if ((r = sshbuf_put(blob, MARK_END, MARK_END_LEN)) != 0)
3066 		goto out;
3067 
3068 	/* success */
3069 	r = 0;
3070 
3071  out:
3072 	sshbuf_free(kdf);
3073 	sshbuf_free(encoded);
3074 	sshbuf_free(encrypted);
3075 	cipher_cleanup(&ciphercontext);
3076 	explicit_bzero(salt, sizeof(salt));
3077 	if (key != NULL) {
3078 		explicit_bzero(key, keylen + ivlen);
3079 		free(key);
3080 	}
3081 	if (pubkeyblob != NULL) {
3082 		explicit_bzero(pubkeyblob, pubkeylen);
3083 		free(pubkeyblob);
3084 	}
3085 	if (b64 != NULL) {
3086 		explicit_bzero(b64, strlen(b64));
3087 		free(b64);
3088 	}
3089 	return r;
3090 }
3091 
3092 static int
3093 sshkey_parse_private2(struct sshbuf *blob, int type, const char *passphrase,
3094     struct sshkey **keyp, char **commentp)
3095 {
3096 	char *comment = NULL, *ciphername = NULL, *kdfname = NULL;
3097 	const struct sshcipher *cipher = NULL;
3098 	const u_char *cp;
3099 	int r = SSH_ERR_INTERNAL_ERROR;
3100 	size_t encoded_len;
3101 	size_t i, keylen = 0, ivlen = 0, authlen = 0, slen = 0;
3102 	struct sshbuf *encoded = NULL, *decoded = NULL;
3103 	struct sshbuf *kdf = NULL, *decrypted = NULL;
3104 	struct sshcipher_ctx ciphercontext;
3105 	struct sshkey *k = NULL;
3106 	u_char *key = NULL, *salt = NULL, *dp, pad, last;
3107 	u_int blocksize, rounds, nkeys, encrypted_len, check1, check2;
3108 
3109 	memset(&ciphercontext, 0, sizeof(ciphercontext));
3110 	if (keyp != NULL)
3111 		*keyp = NULL;
3112 	if (commentp != NULL)
3113 		*commentp = NULL;
3114 
3115 	if ((encoded = sshbuf_new()) == NULL ||
3116 	    (decoded = sshbuf_new()) == NULL ||
3117 	    (decrypted = sshbuf_new()) == NULL) {
3118 		r = SSH_ERR_ALLOC_FAIL;
3119 		goto out;
3120 	}
3121 
3122 	/* check preamble */
3123 	cp = sshbuf_ptr(blob);
3124 	encoded_len = sshbuf_len(blob);
3125 	if (encoded_len < (MARK_BEGIN_LEN + MARK_END_LEN) ||
3126 	    memcmp(cp, MARK_BEGIN, MARK_BEGIN_LEN) != 0) {
3127 		r = SSH_ERR_INVALID_FORMAT;
3128 		goto out;
3129 	}
3130 	cp += MARK_BEGIN_LEN;
3131 	encoded_len -= MARK_BEGIN_LEN;
3132 
3133 	/* Look for end marker, removing whitespace as we go */
3134 	while (encoded_len > 0) {
3135 		if (*cp != '\n' && *cp != '\r') {
3136 			if ((r = sshbuf_put_u8(encoded, *cp)) != 0)
3137 				goto out;
3138 		}
3139 		last = *cp;
3140 		encoded_len--;
3141 		cp++;
3142 		if (last == '\n') {
3143 			if (encoded_len >= MARK_END_LEN &&
3144 			    memcmp(cp, MARK_END, MARK_END_LEN) == 0) {
3145 				/* \0 terminate */
3146 				if ((r = sshbuf_put_u8(encoded, 0)) != 0)
3147 					goto out;
3148 				break;
3149 			}
3150 		}
3151 	}
3152 	if (encoded_len == 0) {
3153 		r = SSH_ERR_INVALID_FORMAT;
3154 		goto out;
3155 	}
3156 
3157 	/* decode base64 */
3158 	if ((r = sshbuf_b64tod(decoded, (char *)sshbuf_ptr(encoded))) != 0)
3159 		goto out;
3160 
3161 	/* check magic */
3162 	if (sshbuf_len(decoded) < sizeof(AUTH_MAGIC) ||
3163 	    memcmp(sshbuf_ptr(decoded), AUTH_MAGIC, sizeof(AUTH_MAGIC))) {
3164 		r = SSH_ERR_INVALID_FORMAT;
3165 		goto out;
3166 	}
3167 	/* parse public portion of key */
3168 	if ((r = sshbuf_consume(decoded, sizeof(AUTH_MAGIC))) != 0 ||
3169 	    (r = sshbuf_get_cstring(decoded, &ciphername, NULL)) != 0 ||
3170 	    (r = sshbuf_get_cstring(decoded, &kdfname, NULL)) != 0 ||
3171 	    (r = sshbuf_froms(decoded, &kdf)) != 0 ||
3172 	    (r = sshbuf_get_u32(decoded, &nkeys)) != 0 ||
3173 	    (r = sshbuf_skip_string(decoded)) != 0 || /* pubkey */
3174 	    (r = sshbuf_get_u32(decoded, &encrypted_len)) != 0)
3175 		goto out;
3176 
3177 	if ((cipher = cipher_by_name(ciphername)) == NULL) {
3178 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3179 		goto out;
3180 	}
3181 	if ((passphrase == NULL || strlen(passphrase) == 0) &&
3182 	    strcmp(ciphername, "none") != 0) {
3183 		/* passphrase required */
3184 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3185 		goto out;
3186 	}
3187 	if (strcmp(kdfname, "none") != 0 && strcmp(kdfname, "bcrypt") != 0) {
3188 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3189 		goto out;
3190 	}
3191 	if (!strcmp(kdfname, "none") && strcmp(ciphername, "none") != 0) {
3192 		r = SSH_ERR_INVALID_FORMAT;
3193 		goto out;
3194 	}
3195 	if (nkeys != 1) {
3196 		/* XXX only one key supported */
3197 		r = SSH_ERR_INVALID_FORMAT;
3198 		goto out;
3199 	}
3200 
3201 	/* check size of encrypted key blob */
3202 	blocksize = cipher_blocksize(cipher);
3203 	if (encrypted_len < blocksize || (encrypted_len % blocksize) != 0) {
3204 		r = SSH_ERR_INVALID_FORMAT;
3205 		goto out;
3206 	}
3207 
3208 	/* setup key */
3209 	keylen = cipher_keylen(cipher);
3210 	ivlen = cipher_ivlen(cipher);
3211 	authlen = cipher_authlen(cipher);
3212 	if ((key = calloc(1, keylen + ivlen)) == NULL) {
3213 		r = SSH_ERR_ALLOC_FAIL;
3214 		goto out;
3215 	}
3216 	if (strcmp(kdfname, "bcrypt") == 0) {
3217 		if ((r = sshbuf_get_string(kdf, &salt, &slen)) != 0 ||
3218 		    (r = sshbuf_get_u32(kdf, &rounds)) != 0)
3219 			goto out;
3220 		if (bcrypt_pbkdf(passphrase, strlen(passphrase), salt, slen,
3221 		    key, keylen + ivlen, rounds) < 0) {
3222 			r = SSH_ERR_INVALID_FORMAT;
3223 			goto out;
3224 		}
3225 	}
3226 
3227 	/* check that an appropriate amount of auth data is present */
3228 	if (sshbuf_len(decoded) < encrypted_len + authlen) {
3229 		r = SSH_ERR_INVALID_FORMAT;
3230 		goto out;
3231 	}
3232 
3233 	/* decrypt private portion of key */
3234 	if ((r = sshbuf_reserve(decrypted, encrypted_len, &dp)) != 0 ||
3235 	    (r = cipher_init(&ciphercontext, cipher, key, keylen,
3236 	    key + keylen, ivlen, 0)) != 0)
3237 		goto out;
3238 	if ((r = cipher_crypt(&ciphercontext, 0, dp, sshbuf_ptr(decoded),
3239 	    encrypted_len, 0, authlen)) != 0) {
3240 		/* an integrity error here indicates an incorrect passphrase */
3241 		if (r == SSH_ERR_MAC_INVALID)
3242 			r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3243 		goto out;
3244 	}
3245 	if ((r = sshbuf_consume(decoded, encrypted_len + authlen)) != 0)
3246 		goto out;
3247 	/* there should be no trailing data */
3248 	if (sshbuf_len(decoded) != 0) {
3249 		r = SSH_ERR_INVALID_FORMAT;
3250 		goto out;
3251 	}
3252 
3253 	/* check check bytes */
3254 	if ((r = sshbuf_get_u32(decrypted, &check1)) != 0 ||
3255 	    (r = sshbuf_get_u32(decrypted, &check2)) != 0)
3256 		goto out;
3257 	if (check1 != check2) {
3258 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3259 		goto out;
3260 	}
3261 
3262 	/* Load the private key and comment */
3263 	if ((r = sshkey_private_deserialize(decrypted, &k)) != 0 ||
3264 	    (r = sshbuf_get_cstring(decrypted, &comment, NULL)) != 0)
3265 		goto out;
3266 
3267 	/* Check deterministic padding */
3268 	i = 0;
3269 	while (sshbuf_len(decrypted)) {
3270 		if ((r = sshbuf_get_u8(decrypted, &pad)) != 0)
3271 			goto out;
3272 		if (pad != (++i & 0xff)) {
3273 			r = SSH_ERR_INVALID_FORMAT;
3274 			goto out;
3275 		}
3276 	}
3277 
3278 	/* XXX decode pubkey and check against private */
3279 
3280 	/* success */
3281 	r = 0;
3282 	if (keyp != NULL) {
3283 		*keyp = k;
3284 		k = NULL;
3285 	}
3286 	if (commentp != NULL) {
3287 		*commentp = comment;
3288 		comment = NULL;
3289 	}
3290  out:
3291 	pad = 0;
3292 	cipher_cleanup(&ciphercontext);
3293 	free(ciphername);
3294 	free(kdfname);
3295 	free(comment);
3296 	if (salt != NULL) {
3297 		explicit_bzero(salt, slen);
3298 		free(salt);
3299 	}
3300 	if (key != NULL) {
3301 		explicit_bzero(key, keylen + ivlen);
3302 		free(key);
3303 	}
3304 	sshbuf_free(encoded);
3305 	sshbuf_free(decoded);
3306 	sshbuf_free(kdf);
3307 	sshbuf_free(decrypted);
3308 	sshkey_free(k);
3309 	return r;
3310 }
3311 
3312 #if WITH_SSH1
3313 /*
3314  * Serialises the authentication (private) key to a blob, encrypting it with
3315  * passphrase.  The identification of the blob (lowest 64 bits of n) will
3316  * precede the key to provide identification of the key without needing a
3317  * passphrase.
3318  */
3319 static int
3320 sshkey_private_rsa1_to_blob(struct sshkey *key, struct sshbuf *blob,
3321     const char *passphrase, const char *comment)
3322 {
3323 	struct sshbuf *buffer = NULL, *encrypted = NULL;
3324 	u_char buf[8];
3325 	int r, cipher_num;
3326 	struct sshcipher_ctx ciphercontext;
3327 	const struct sshcipher *cipher;
3328 	u_char *cp;
3329 
3330 	/*
3331 	 * If the passphrase is empty, use SSH_CIPHER_NONE to ease converting
3332 	 * to another cipher; otherwise use SSH_AUTHFILE_CIPHER.
3333 	 */
3334 	cipher_num = (strcmp(passphrase, "") == 0) ?
3335 	    SSH_CIPHER_NONE : SSH_CIPHER_3DES;
3336 	if ((cipher = cipher_by_number(cipher_num)) == NULL)
3337 		return SSH_ERR_INTERNAL_ERROR;
3338 
3339 	/* This buffer is used to build the secret part of the private key. */
3340 	if ((buffer = sshbuf_new()) == NULL)
3341 		return SSH_ERR_ALLOC_FAIL;
3342 
3343 	/* Put checkbytes for checking passphrase validity. */
3344 	if ((r = sshbuf_reserve(buffer, 4, &cp)) != 0)
3345 		goto out;
3346 	arc4random_buf(cp, 2);
3347 	memcpy(cp + 2, cp, 2);
3348 
3349 	/*
3350 	 * Store the private key (n and e will not be stored because they
3351 	 * will be stored in plain text, and storing them also in encrypted
3352 	 * format would just give known plaintext).
3353 	 * Note: q and p are stored in reverse order to SSL.
3354 	 */
3355 	if ((r = sshbuf_put_bignum1(buffer, key->rsa->d)) != 0 ||
3356 	    (r = sshbuf_put_bignum1(buffer, key->rsa->iqmp)) != 0 ||
3357 	    (r = sshbuf_put_bignum1(buffer, key->rsa->q)) != 0 ||
3358 	    (r = sshbuf_put_bignum1(buffer, key->rsa->p)) != 0)
3359 		goto out;
3360 
3361 	/* Pad the part to be encrypted to a size that is a multiple of 8. */
3362 	explicit_bzero(buf, 8);
3363 	if ((r = sshbuf_put(buffer, buf, 8 - (sshbuf_len(buffer) % 8))) != 0)
3364 		goto out;
3365 
3366 	/* This buffer will be used to contain the data in the file. */
3367 	if ((encrypted = sshbuf_new()) == NULL) {
3368 		r = SSH_ERR_ALLOC_FAIL;
3369 		goto out;
3370 	}
3371 
3372 	/* First store keyfile id string. */
3373 	if ((r = sshbuf_put(encrypted, LEGACY_BEGIN,
3374 	    sizeof(LEGACY_BEGIN))) != 0)
3375 		goto out;
3376 
3377 	/* Store cipher type and "reserved" field. */
3378 	if ((r = sshbuf_put_u8(encrypted, cipher_num)) != 0 ||
3379 	    (r = sshbuf_put_u32(encrypted, 0)) != 0)
3380 		goto out;
3381 
3382 	/* Store public key.  This will be in plain text. */
3383 	if ((r = sshbuf_put_u32(encrypted, BN_num_bits(key->rsa->n))) != 0 ||
3384 	    (r = sshbuf_put_bignum1(encrypted, key->rsa->n) != 0) ||
3385 	    (r = sshbuf_put_bignum1(encrypted, key->rsa->e) != 0) ||
3386 	    (r = sshbuf_put_cstring(encrypted, comment) != 0))
3387 		goto out;
3388 
3389 	/* Allocate space for the private part of the key in the buffer. */
3390 	if ((r = sshbuf_reserve(encrypted, sshbuf_len(buffer), &cp)) != 0)
3391 		goto out;
3392 
3393 	if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase,
3394 	    CIPHER_ENCRYPT)) != 0)
3395 		goto out;
3396 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3397 	    sshbuf_ptr(buffer), sshbuf_len(buffer), 0, 0)) != 0)
3398 		goto out;
3399 	if ((r = cipher_cleanup(&ciphercontext)) != 0)
3400 		goto out;
3401 
3402 	r = sshbuf_putb(blob, encrypted);
3403 
3404  out:
3405 	explicit_bzero(&ciphercontext, sizeof(ciphercontext));
3406 	explicit_bzero(buf, sizeof(buf));
3407 	if (buffer != NULL)
3408 		sshbuf_free(buffer);
3409 	if (encrypted != NULL)
3410 		sshbuf_free(encrypted);
3411 
3412 	return r;
3413 }
3414 #endif /* WITH_SSH1 */
3415 
3416 #ifdef WITH_OPENSSL
3417 /* convert SSH v2 key in OpenSSL PEM format */
3418 static int
3419 sshkey_private_pem_to_blob(struct sshkey *key, struct sshbuf *blob,
3420     const char *_passphrase, const char *comment)
3421 {
3422 	int success, r;
3423 	int blen, len = strlen(_passphrase);
3424 	u_char *passphrase = (len > 0) ? (u_char *)_passphrase : NULL;
3425 	const EVP_CIPHER *cipher = (len > 0) ? EVP_aes_128_cbc() : NULL;
3426 	const u_char *bptr;
3427 	BIO *bio = NULL;
3428 
3429 	if (len > 0 && len <= 4)
3430 		return SSH_ERR_PASSPHRASE_TOO_SHORT;
3431 	if ((bio = BIO_new(BIO_s_mem())) == NULL)
3432 		return SSH_ERR_ALLOC_FAIL;
3433 
3434 	switch (key->type) {
3435 	case KEY_DSA:
3436 		success = PEM_write_bio_DSAPrivateKey(bio, key->dsa,
3437 		    cipher, passphrase, len, NULL, NULL);
3438 		break;
3439 	case KEY_ECDSA:
3440 		success = PEM_write_bio_ECPrivateKey(bio, key->ecdsa,
3441 		    cipher, passphrase, len, NULL, NULL);
3442 		break;
3443 	case KEY_RSA:
3444 		success = PEM_write_bio_RSAPrivateKey(bio, key->rsa,
3445 		    cipher, passphrase, len, NULL, NULL);
3446 		break;
3447 	default:
3448 		success = 0;
3449 		break;
3450 	}
3451 	if (success == 0) {
3452 		r = SSH_ERR_LIBCRYPTO_ERROR;
3453 		goto out;
3454 	}
3455 	if ((blen = BIO_get_mem_data(bio, &bptr)) <= 0) {
3456 		r = SSH_ERR_INTERNAL_ERROR;
3457 		goto out;
3458 	}
3459 	if ((r = sshbuf_put(blob, bptr, blen)) != 0)
3460 		goto out;
3461 	r = 0;
3462  out:
3463 	BIO_free(bio);
3464 	return r;
3465 }
3466 #endif /* WITH_OPENSSL */
3467 
3468 /* Serialise "key" to buffer "blob" */
3469 int
3470 sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
3471     const char *passphrase, const char *comment,
3472     int force_new_format, const char *new_format_cipher, int new_format_rounds)
3473 {
3474 	switch (key->type) {
3475 #ifdef WITH_SSH1
3476 	case KEY_RSA1:
3477 		return sshkey_private_rsa1_to_blob(key, blob,
3478 		    passphrase, comment);
3479 #endif /* WITH_SSH1 */
3480 #ifdef WITH_OPENSSL
3481 	case KEY_DSA:
3482 	case KEY_ECDSA:
3483 	case KEY_RSA:
3484 		if (force_new_format) {
3485 			return sshkey_private_to_blob2(key, blob, passphrase,
3486 			    comment, new_format_cipher, new_format_rounds);
3487 		}
3488 		return sshkey_private_pem_to_blob(key, blob,
3489 		    passphrase, comment);
3490 #endif /* WITH_OPENSSL */
3491 	case KEY_ED25519:
3492 		return sshkey_private_to_blob2(key, blob, passphrase,
3493 		    comment, new_format_cipher, new_format_rounds);
3494 	default:
3495 		return SSH_ERR_KEY_TYPE_UNKNOWN;
3496 	}
3497 }
3498 
3499 #ifdef WITH_SSH1
3500 /*
3501  * Parse the public, unencrypted portion of a RSA1 key.
3502  */
3503 int
3504 sshkey_parse_public_rsa1_fileblob(struct sshbuf *blob,
3505     struct sshkey **keyp, char **commentp)
3506 {
3507 	int r;
3508 	struct sshkey *pub = NULL;
3509 	struct sshbuf *copy = NULL;
3510 
3511 	if (keyp != NULL)
3512 		*keyp = NULL;
3513 	if (commentp != NULL)
3514 		*commentp = NULL;
3515 
3516 	/* Check that it is at least big enough to contain the ID string. */
3517 	if (sshbuf_len(blob) < sizeof(LEGACY_BEGIN))
3518 		return SSH_ERR_INVALID_FORMAT;
3519 
3520 	/*
3521 	 * Make sure it begins with the id string.  Consume the id string
3522 	 * from the buffer.
3523 	 */
3524 	if (memcmp(sshbuf_ptr(blob), LEGACY_BEGIN, sizeof(LEGACY_BEGIN)) != 0)
3525 		return SSH_ERR_INVALID_FORMAT;
3526 	/* Make a working copy of the keyblob and skip past the magic */
3527 	if ((copy = sshbuf_fromb(blob)) == NULL)
3528 		return SSH_ERR_ALLOC_FAIL;
3529 	if ((r = sshbuf_consume(copy, sizeof(LEGACY_BEGIN))) != 0)
3530 		goto out;
3531 
3532 	/* Skip cipher type, reserved data and key bits. */
3533 	if ((r = sshbuf_get_u8(copy, NULL)) != 0 ||	/* cipher type */
3534 	    (r = sshbuf_get_u32(copy, NULL)) != 0 ||	/* reserved */
3535 	    (r = sshbuf_get_u32(copy, NULL)) != 0)	/* key bits */
3536 		goto out;
3537 
3538 	/* Read the public key from the buffer. */
3539 	if ((pub = sshkey_new(KEY_RSA1)) == NULL ||
3540 	    (r = sshbuf_get_bignum1(copy, pub->rsa->n)) != 0 ||
3541 	    (r = sshbuf_get_bignum1(copy, pub->rsa->e)) != 0)
3542 		goto out;
3543 
3544 	/* Finally, the comment */
3545 	if ((r = sshbuf_get_string(copy, (u_char**)commentp, NULL)) != 0)
3546 		goto out;
3547 
3548 	/* The encrypted private part is not parsed by this function. */
3549 
3550 	r = 0;
3551 	if (keyp != NULL)
3552 		*keyp = pub;
3553 	else
3554 		sshkey_free(pub);
3555 	pub = NULL;
3556 
3557  out:
3558 	if (copy != NULL)
3559 		sshbuf_free(copy);
3560 	if (pub != NULL)
3561 		sshkey_free(pub);
3562 	return r;
3563 }
3564 
3565 static int
3566 sshkey_parse_private_rsa1(struct sshbuf *blob, const char *passphrase,
3567     struct sshkey **keyp, char **commentp)
3568 {
3569 	int r;
3570 	u_int16_t check1, check2;
3571 	u_int8_t cipher_type;
3572 	struct sshbuf *decrypted = NULL, *copy = NULL;
3573 	u_char *cp;
3574 	char *comment = NULL;
3575 	struct sshcipher_ctx ciphercontext;
3576 	const struct sshcipher *cipher;
3577 	struct sshkey *prv = NULL;
3578 
3579 	*keyp = NULL;
3580 	if (commentp != NULL)
3581 		*commentp = NULL;
3582 
3583 	/* Check that it is at least big enough to contain the ID string. */
3584 	if (sshbuf_len(blob) < sizeof(LEGACY_BEGIN))
3585 		return SSH_ERR_INVALID_FORMAT;
3586 
3587 	/*
3588 	 * Make sure it begins with the id string.  Consume the id string
3589 	 * from the buffer.
3590 	 */
3591 	if (memcmp(sshbuf_ptr(blob), LEGACY_BEGIN, sizeof(LEGACY_BEGIN)) != 0)
3592 		return SSH_ERR_INVALID_FORMAT;
3593 
3594 	if ((prv = sshkey_new_private(KEY_RSA1)) == NULL) {
3595 		r = SSH_ERR_ALLOC_FAIL;
3596 		goto out;
3597 	}
3598 	if ((copy = sshbuf_fromb(blob)) == NULL ||
3599 	    (decrypted = sshbuf_new()) == NULL) {
3600 		r = SSH_ERR_ALLOC_FAIL;
3601 		goto out;
3602 	}
3603 	if ((r = sshbuf_consume(copy, sizeof(LEGACY_BEGIN))) != 0)
3604 		goto out;
3605 
3606 	/* Read cipher type. */
3607 	if ((r = sshbuf_get_u8(copy, &cipher_type)) != 0 ||
3608 	    (r = sshbuf_get_u32(copy, NULL)) != 0)	/* reserved */
3609 		goto out;
3610 
3611 	/* Read the public key and comment from the buffer. */
3612 	if ((r = sshbuf_get_u32(copy, NULL)) != 0 ||	/* key bits */
3613 	    (r = sshbuf_get_bignum1(copy, prv->rsa->n)) != 0 ||
3614 	    (r = sshbuf_get_bignum1(copy, prv->rsa->e)) != 0 ||
3615 	    (r = sshbuf_get_cstring(copy, &comment, NULL)) != 0)
3616 		goto out;
3617 
3618 	/* Check that it is a supported cipher. */
3619 	cipher = cipher_by_number(cipher_type);
3620 	if (cipher == NULL) {
3621 		r = SSH_ERR_KEY_UNKNOWN_CIPHER;
3622 		goto out;
3623 	}
3624 	/* Initialize space for decrypted data. */
3625 	if ((r = sshbuf_reserve(decrypted, sshbuf_len(copy), &cp)) != 0)
3626 		goto out;
3627 
3628 	/* Rest of the buffer is encrypted.  Decrypt it using the passphrase. */
3629 	if ((r = cipher_set_key_string(&ciphercontext, cipher, passphrase,
3630 	    CIPHER_DECRYPT)) != 0)
3631 		goto out;
3632 	if ((r = cipher_crypt(&ciphercontext, 0, cp,
3633 	    sshbuf_ptr(copy), sshbuf_len(copy), 0, 0)) != 0) {
3634 		cipher_cleanup(&ciphercontext);
3635 		goto out;
3636 	}
3637 	if ((r = cipher_cleanup(&ciphercontext)) != 0)
3638 		goto out;
3639 
3640 	if ((r = sshbuf_get_u16(decrypted, &check1)) != 0 ||
3641 	    (r = sshbuf_get_u16(decrypted, &check2)) != 0)
3642 		goto out;
3643 	if (check1 != check2) {
3644 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3645 		goto out;
3646 	}
3647 
3648 	/* Read the rest of the private key. */
3649 	if ((r = sshbuf_get_bignum1(decrypted, prv->rsa->d)) != 0 ||
3650 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->iqmp)) != 0 ||
3651 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->q)) != 0 ||
3652 	    (r = sshbuf_get_bignum1(decrypted, prv->rsa->p)) != 0)
3653 		goto out;
3654 
3655 	/* calculate p-1 and q-1 */
3656 	if ((r = rsa_generate_additional_parameters(prv->rsa)) != 0)
3657 		goto out;
3658 
3659 	/* enable blinding */
3660 	if (RSA_blinding_on(prv->rsa, NULL) != 1) {
3661 		r = SSH_ERR_LIBCRYPTO_ERROR;
3662 		goto out;
3663 	}
3664 	r = 0;
3665 	*keyp = prv;
3666 	prv = NULL;
3667 	if (commentp != NULL) {
3668 		*commentp = comment;
3669 		comment = NULL;
3670 	}
3671  out:
3672 	explicit_bzero(&ciphercontext, sizeof(ciphercontext));
3673 	if (comment != NULL)
3674 		free(comment);
3675 	if (prv != NULL)
3676 		sshkey_free(prv);
3677 	if (copy != NULL)
3678 		sshbuf_free(copy);
3679 	if (decrypted != NULL)
3680 		sshbuf_free(decrypted);
3681 	return r;
3682 }
3683 #endif /* WITH_SSH1 */
3684 
3685 #ifdef WITH_OPENSSL
3686 static int
3687 sshkey_parse_private_pem_fileblob(struct sshbuf *blob, int type,
3688     const char *passphrase, struct sshkey **keyp)
3689 {
3690 	EVP_PKEY *pk = NULL;
3691 	struct sshkey *prv = NULL;
3692 	BIO *bio = NULL;
3693 	int r;
3694 
3695 	*keyp = NULL;
3696 
3697 	if ((bio = BIO_new(BIO_s_mem())) == NULL || sshbuf_len(blob) > INT_MAX)
3698 		return SSH_ERR_ALLOC_FAIL;
3699 	if (BIO_write(bio, sshbuf_ptr(blob), sshbuf_len(blob)) !=
3700 	    (int)sshbuf_len(blob)) {
3701 		r = SSH_ERR_ALLOC_FAIL;
3702 		goto out;
3703 	}
3704 
3705 	if ((pk = PEM_read_bio_PrivateKey(bio, NULL, NULL,
3706 	    (char *)passphrase)) == NULL) {
3707 		r = SSH_ERR_KEY_WRONG_PASSPHRASE;
3708 		goto out;
3709 	}
3710 	if (pk->type == EVP_PKEY_RSA &&
3711 	    (type == KEY_UNSPEC || type == KEY_RSA)) {
3712 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3713 			r = SSH_ERR_ALLOC_FAIL;
3714 			goto out;
3715 		}
3716 		prv->rsa = EVP_PKEY_get1_RSA(pk);
3717 		prv->type = KEY_RSA;
3718 #ifdef DEBUG_PK
3719 		RSA_print_fp(stderr, prv->rsa, 8);
3720 #endif
3721 		if (RSA_blinding_on(prv->rsa, NULL) != 1) {
3722 			r = SSH_ERR_LIBCRYPTO_ERROR;
3723 			goto out;
3724 		}
3725 	} else if (pk->type == EVP_PKEY_DSA &&
3726 	    (type == KEY_UNSPEC || type == KEY_DSA)) {
3727 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3728 			r = SSH_ERR_ALLOC_FAIL;
3729 			goto out;
3730 		}
3731 		prv->dsa = EVP_PKEY_get1_DSA(pk);
3732 		prv->type = KEY_DSA;
3733 #ifdef DEBUG_PK
3734 		DSA_print_fp(stderr, prv->dsa, 8);
3735 #endif
3736 	} else if (pk->type == EVP_PKEY_EC &&
3737 	    (type == KEY_UNSPEC || type == KEY_ECDSA)) {
3738 		if ((prv = sshkey_new(KEY_UNSPEC)) == NULL) {
3739 			r = SSH_ERR_ALLOC_FAIL;
3740 			goto out;
3741 		}
3742 		prv->ecdsa = EVP_PKEY_get1_EC_KEY(pk);
3743 		prv->type = KEY_ECDSA;
3744 		prv->ecdsa_nid = sshkey_ecdsa_key_to_nid(prv->ecdsa);
3745 		if (prv->ecdsa_nid == -1 ||
3746 		    sshkey_curve_nid_to_name(prv->ecdsa_nid) == NULL ||
3747 		    sshkey_ec_validate_public(EC_KEY_get0_group(prv->ecdsa),
3748 		    EC_KEY_get0_public_key(prv->ecdsa)) != 0 ||
3749 		    sshkey_ec_validate_private(prv->ecdsa) != 0) {
3750 			r = SSH_ERR_INVALID_FORMAT;
3751 			goto out;
3752 		}
3753 #ifdef DEBUG_PK
3754 		if (prv != NULL && prv->ecdsa != NULL)
3755 			sshkey_dump_ec_key(prv->ecdsa);
3756 #endif
3757 	} else {
3758 		r = SSH_ERR_INVALID_FORMAT;
3759 		goto out;
3760 	}
3761 	r = 0;
3762 	*keyp = prv;
3763 	prv = NULL;
3764  out:
3765 	BIO_free(bio);
3766 	if (pk != NULL)
3767 		EVP_PKEY_free(pk);
3768 	if (prv != NULL)
3769 		sshkey_free(prv);
3770 	return r;
3771 }
3772 #endif /* WITH_OPENSSL */
3773 
3774 int
3775 sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
3776     const char *passphrase, struct sshkey **keyp, char **commentp)
3777 {
3778 	int r;
3779 
3780 	*keyp = NULL;
3781 	if (commentp != NULL)
3782 		*commentp = NULL;
3783 
3784 	switch (type) {
3785 #ifdef WITH_SSH1
3786 	case KEY_RSA1:
3787 		return sshkey_parse_private_rsa1(blob, passphrase,
3788 		    keyp, commentp);
3789 #endif /* WITH_SSH1 */
3790 #ifdef WITH_OPENSSL
3791 	case KEY_DSA:
3792 	case KEY_ECDSA:
3793 	case KEY_RSA:
3794 		return sshkey_parse_private_pem_fileblob(blob, type,
3795 		    passphrase, keyp);
3796 #endif /* WITH_OPENSSL */
3797 	case KEY_ED25519:
3798 		return sshkey_parse_private2(blob, type, passphrase,
3799 		    keyp, commentp);
3800 	case KEY_UNSPEC:
3801 		if ((r = sshkey_parse_private2(blob, type, passphrase, keyp,
3802 		    commentp)) == 0)
3803 			return 0;
3804 #ifdef WITH_OPENSSL
3805 		return sshkey_parse_private_pem_fileblob(blob, type,
3806 		    passphrase, keyp);
3807 #else
3808 		return SSH_ERR_INVALID_FORMAT;
3809 #endif /* WITH_OPENSSL */
3810 	default:
3811 		return SSH_ERR_KEY_TYPE_UNKNOWN;
3812 	}
3813 }
3814 
3815 int
3816 sshkey_parse_private_fileblob(struct sshbuf *buffer, const char *passphrase,
3817     const char *filename, struct sshkey **keyp, char **commentp)
3818 {
3819 	int r;
3820 
3821 	if (keyp != NULL)
3822 		*keyp = NULL;
3823 	if (commentp != NULL)
3824 		*commentp = NULL;
3825 
3826 #ifdef WITH_SSH1
3827 	/* it's a SSH v1 key if the public key part is readable */
3828 	if ((r = sshkey_parse_public_rsa1_fileblob(buffer, NULL, NULL)) == 0) {
3829 		return sshkey_parse_private_fileblob_type(buffer, KEY_RSA1,
3830 		    passphrase, keyp, commentp);
3831 	}
3832 #endif /* WITH_SSH1 */
3833 	if ((r = sshkey_parse_private_fileblob_type(buffer, KEY_UNSPEC,
3834 	    passphrase, keyp, commentp)) == 0)
3835 		return 0;
3836 	return r;
3837 }
3838