xref: /openbsd-src/usr.bin/ssh/ssh-keygen.c (revision d2c5a4743fb945f45b034a3a830a96f7e1bc695d)
1 /* $OpenBSD: ssh-keygen.c,v 1.421 2020/10/18 11:32:02 djm Exp $ */
2 /*
3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
4  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5  *                    All rights reserved
6  * Identity and host key generation and maintenance.
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  */
14 
15 #include <sys/types.h>
16 #include <sys/socket.h>
17 #include <sys/stat.h>
18 
19 #ifdef WITH_OPENSSL
20 #include <openssl/evp.h>
21 #include <openssl/pem.h>
22 #endif
23 
24 #include <stdint.h>
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <netdb.h>
28 #include <pwd.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <stdarg.h>
33 #include <unistd.h>
34 #include <limits.h>
35 #include <locale.h>
36 
37 #include "xmalloc.h"
38 #include "sshkey.h"
39 #include "authfile.h"
40 #include "sshbuf.h"
41 #include "pathnames.h"
42 #include "log.h"
43 #include "misc.h"
44 #include "match.h"
45 #include "hostfile.h"
46 #include "dns.h"
47 #include "ssh.h"
48 #include "ssh2.h"
49 #include "ssherr.h"
50 #include "atomicio.h"
51 #include "krl.h"
52 #include "digest.h"
53 #include "utf8.h"
54 #include "authfd.h"
55 #include "sshsig.h"
56 #include "ssh-sk.h"
57 #include "sk-api.h" /* XXX for SSH_SK_USER_PRESENCE_REQD; remove */
58 
59 #ifdef ENABLE_PKCS11
60 #include "ssh-pkcs11.h"
61 #endif
62 
63 #ifdef WITH_OPENSSL
64 # define DEFAULT_KEY_TYPE_NAME "rsa"
65 #else
66 # define DEFAULT_KEY_TYPE_NAME "ed25519"
67 #endif
68 
69 /*
70  * Default number of bits in the RSA, DSA and ECDSA keys.  These value can be
71  * overridden on the command line.
72  *
73  * These values, with the exception of DSA, provide security equivalent to at
74  * least 128 bits of security according to NIST Special Publication 800-57:
75  * Recommendation for Key Management Part 1 rev 4 section 5.6.1.
76  * For DSA it (and FIPS-186-4 section 4.2) specifies that the only size for
77  * which a 160bit hash is acceptable is 1kbit, and since ssh-dss specifies only
78  * SHA1 we limit the DSA key size 1k bits.
79  */
80 #define DEFAULT_BITS		3072
81 #define DEFAULT_BITS_DSA	1024
82 #define DEFAULT_BITS_ECDSA	256
83 
84 static int quiet = 0;
85 
86 /* Flag indicating that we just want to see the key fingerprint */
87 static int print_fingerprint = 0;
88 static int print_bubblebabble = 0;
89 
90 /* Hash algorithm to use for fingerprints. */
91 static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
92 
93 /* The identity file name, given on the command line or entered by the user. */
94 static char identity_file[PATH_MAX];
95 static int have_identity = 0;
96 
97 /* This is set to the passphrase if given on the command line. */
98 static char *identity_passphrase = NULL;
99 
100 /* This is set to the new passphrase if given on the command line. */
101 static char *identity_new_passphrase = NULL;
102 
103 /* Key type when certifying */
104 static u_int cert_key_type = SSH2_CERT_TYPE_USER;
105 
106 /* "key ID" of signed key */
107 static char *cert_key_id = NULL;
108 
109 /* Comma-separated list of principal names for certifying keys */
110 static char *cert_principals = NULL;
111 
112 /* Validity period for certificates */
113 static u_int64_t cert_valid_from = 0;
114 static u_int64_t cert_valid_to = ~0ULL;
115 
116 /* Certificate options */
117 #define CERTOPT_X_FWD				(1)
118 #define CERTOPT_AGENT_FWD			(1<<1)
119 #define CERTOPT_PORT_FWD			(1<<2)
120 #define CERTOPT_PTY				(1<<3)
121 #define CERTOPT_USER_RC				(1<<4)
122 #define CERTOPT_NO_REQUIRE_USER_PRESENCE	(1<<5)
123 #define CERTOPT_DEFAULT	(CERTOPT_X_FWD|CERTOPT_AGENT_FWD| \
124 			 CERTOPT_PORT_FWD|CERTOPT_PTY|CERTOPT_USER_RC)
125 static u_int32_t certflags_flags = CERTOPT_DEFAULT;
126 static char *certflags_command = NULL;
127 static char *certflags_src_addr = NULL;
128 
129 /* Arbitrary extensions specified by user */
130 struct cert_ext {
131 	char *key;
132 	char *val;
133 	int crit;
134 };
135 static struct cert_ext *cert_ext;
136 static size_t ncert_ext;
137 
138 /* Conversion to/from various formats */
139 enum {
140 	FMT_RFC4716,
141 	FMT_PKCS8,
142 	FMT_PEM
143 } convert_format = FMT_RFC4716;
144 
145 static char *key_type_name = NULL;
146 
147 /* Load key from this PKCS#11 provider */
148 static char *pkcs11provider = NULL;
149 
150 /* FIDO/U2F provider to use */
151 static char *sk_provider = NULL;
152 
153 /* Format for writing private keys */
154 static int private_key_format = SSHKEY_PRIVATE_OPENSSH;
155 
156 /* Cipher for new-format private keys */
157 static char *openssh_format_cipher = NULL;
158 
159 /* Number of KDF rounds to derive new format keys. */
160 static int rounds = 0;
161 
162 /* argv0 */
163 extern char *__progname;
164 
165 static char hostname[NI_MAXHOST];
166 
167 #ifdef WITH_OPENSSL
168 /* moduli.c */
169 int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
170 int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
171     unsigned long);
172 #endif
173 
174 static void
175 type_bits_valid(int type, const char *name, u_int32_t *bitsp)
176 {
177 	if (type == KEY_UNSPEC)
178 		fatal("unknown key type %s", key_type_name);
179 	if (*bitsp == 0) {
180 #ifdef WITH_OPENSSL
181 		u_int nid;
182 
183 		switch(type) {
184 		case KEY_DSA:
185 			*bitsp = DEFAULT_BITS_DSA;
186 			break;
187 		case KEY_ECDSA:
188 			if (name != NULL &&
189 			    (nid = sshkey_ecdsa_nid_from_name(name)) > 0)
190 				*bitsp = sshkey_curve_nid_to_bits(nid);
191 			if (*bitsp == 0)
192 				*bitsp = DEFAULT_BITS_ECDSA;
193 			break;
194 		case KEY_RSA:
195 			*bitsp = DEFAULT_BITS;
196 			break;
197 		}
198 #endif
199 	}
200 #ifdef WITH_OPENSSL
201 	switch (type) {
202 	case KEY_DSA:
203 		if (*bitsp != 1024)
204 			fatal("Invalid DSA key length: must be 1024 bits");
205 		break;
206 	case KEY_RSA:
207 		if (*bitsp < SSH_RSA_MINIMUM_MODULUS_SIZE)
208 			fatal("Invalid RSA key length: minimum is %d bits",
209 			    SSH_RSA_MINIMUM_MODULUS_SIZE);
210 		else if (*bitsp > OPENSSL_RSA_MAX_MODULUS_BITS)
211 			fatal("Invalid RSA key length: maximum is %d bits",
212 			    OPENSSL_RSA_MAX_MODULUS_BITS);
213 		break;
214 	case KEY_ECDSA:
215 		if (sshkey_ecdsa_bits_to_nid(*bitsp) == -1)
216 			fatal("Invalid ECDSA key length: valid lengths are "
217 			    "256, 384 or 521 bits");
218 	}
219 #endif
220 }
221 
222 /*
223  * Checks whether a file exists and, if so, asks the user whether they wish
224  * to overwrite it.
225  * Returns nonzero if the file does not already exist or if the user agrees to
226  * overwrite, or zero otherwise.
227  */
228 static int
229 confirm_overwrite(const char *filename)
230 {
231 	char yesno[3];
232 	struct stat st;
233 
234 	if (stat(filename, &st) != 0)
235 		return 1;
236 	printf("%s already exists.\n", filename);
237 	printf("Overwrite (y/n)? ");
238 	fflush(stdout);
239 	if (fgets(yesno, sizeof(yesno), stdin) == NULL)
240 		return 0;
241 	if (yesno[0] != 'y' && yesno[0] != 'Y')
242 		return 0;
243 	return 1;
244 }
245 
246 static void
247 ask_filename(struct passwd *pw, const char *prompt)
248 {
249 	char buf[1024];
250 	char *name = NULL;
251 
252 	if (key_type_name == NULL)
253 		name = _PATH_SSH_CLIENT_ID_RSA;
254 	else {
255 		switch (sshkey_type_from_name(key_type_name)) {
256 		case KEY_DSA_CERT:
257 		case KEY_DSA:
258 			name = _PATH_SSH_CLIENT_ID_DSA;
259 			break;
260 		case KEY_ECDSA_CERT:
261 		case KEY_ECDSA:
262 			name = _PATH_SSH_CLIENT_ID_ECDSA;
263 			break;
264 		case KEY_ECDSA_SK_CERT:
265 		case KEY_ECDSA_SK:
266 			name = _PATH_SSH_CLIENT_ID_ECDSA_SK;
267 			break;
268 		case KEY_RSA_CERT:
269 		case KEY_RSA:
270 			name = _PATH_SSH_CLIENT_ID_RSA;
271 			break;
272 		case KEY_ED25519:
273 		case KEY_ED25519_CERT:
274 			name = _PATH_SSH_CLIENT_ID_ED25519;
275 			break;
276 		case KEY_ED25519_SK:
277 		case KEY_ED25519_SK_CERT:
278 			name = _PATH_SSH_CLIENT_ID_ED25519_SK;
279 			break;
280 		case KEY_XMSS:
281 		case KEY_XMSS_CERT:
282 			name = _PATH_SSH_CLIENT_ID_XMSS;
283 			break;
284 		default:
285 			fatal("bad key type");
286 		}
287 	}
288 	snprintf(identity_file, sizeof(identity_file),
289 	    "%s/%s", pw->pw_dir, name);
290 	printf("%s (%s): ", prompt, identity_file);
291 	fflush(stdout);
292 	if (fgets(buf, sizeof(buf), stdin) == NULL)
293 		exit(1);
294 	buf[strcspn(buf, "\n")] = '\0';
295 	if (strcmp(buf, "") != 0)
296 		strlcpy(identity_file, buf, sizeof(identity_file));
297 	have_identity = 1;
298 }
299 
300 static struct sshkey *
301 load_identity(const char *filename, char **commentp)
302 {
303 	char *pass;
304 	struct sshkey *prv;
305 	int r;
306 
307 	if (commentp != NULL)
308 		*commentp = NULL;
309 	if ((r = sshkey_load_private(filename, "", &prv, commentp)) == 0)
310 		return prv;
311 	if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
312 		fatal_r(r, "Load key \"%s\"", filename);
313 	if (identity_passphrase)
314 		pass = xstrdup(identity_passphrase);
315 	else
316 		pass = read_passphrase("Enter passphrase: ", RP_ALLOW_STDIN);
317 	r = sshkey_load_private(filename, pass, &prv, commentp);
318 	freezero(pass, strlen(pass));
319 	if (r != 0)
320 		fatal_r(r, "Load key \"%s\"", filename);
321 	return prv;
322 }
323 
324 #define SSH_COM_PUBLIC_BEGIN		"---- BEGIN SSH2 PUBLIC KEY ----"
325 #define SSH_COM_PUBLIC_END		"---- END SSH2 PUBLIC KEY ----"
326 #define SSH_COM_PRIVATE_BEGIN		"---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
327 #define	SSH_COM_PRIVATE_KEY_MAGIC	0x3f6ff9eb
328 
329 #ifdef WITH_OPENSSL
330 static void
331 do_convert_to_ssh2(struct passwd *pw, struct sshkey *k)
332 {
333 	struct sshbuf *b;
334 	char comment[61], *b64;
335 	int r;
336 
337 	if ((b = sshbuf_new()) == NULL)
338 		fatal_f("sshbuf_new failed");
339 	if ((r = sshkey_putb(k, b)) != 0)
340 		fatal_fr(r, "put key");
341 	if ((b64 = sshbuf_dtob64_string(b, 1)) == NULL)
342 		fatal_f("sshbuf_dtob64_string failed");
343 
344 	/* Comment + surrounds must fit into 72 chars (RFC 4716 sec 3.3) */
345 	snprintf(comment, sizeof(comment),
346 	    "%u-bit %s, converted by %s@%s from OpenSSH",
347 	    sshkey_size(k), sshkey_type(k),
348 	    pw->pw_name, hostname);
349 
350 	sshkey_free(k);
351 	sshbuf_free(b);
352 
353 	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
354 	fprintf(stdout, "Comment: \"%s\"\n%s", comment, b64);
355 	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
356 	free(b64);
357 	exit(0);
358 }
359 
360 static void
361 do_convert_to_pkcs8(struct sshkey *k)
362 {
363 	switch (sshkey_type_plain(k->type)) {
364 	case KEY_RSA:
365 		if (!PEM_write_RSA_PUBKEY(stdout, k->rsa))
366 			fatal("PEM_write_RSA_PUBKEY failed");
367 		break;
368 	case KEY_DSA:
369 		if (!PEM_write_DSA_PUBKEY(stdout, k->dsa))
370 			fatal("PEM_write_DSA_PUBKEY failed");
371 		break;
372 	case KEY_ECDSA:
373 		if (!PEM_write_EC_PUBKEY(stdout, k->ecdsa))
374 			fatal("PEM_write_EC_PUBKEY failed");
375 		break;
376 	default:
377 		fatal_f("unsupported key type %s", sshkey_type(k));
378 	}
379 	exit(0);
380 }
381 
382 static void
383 do_convert_to_pem(struct sshkey *k)
384 {
385 	switch (sshkey_type_plain(k->type)) {
386 	case KEY_RSA:
387 		if (!PEM_write_RSAPublicKey(stdout, k->rsa))
388 			fatal("PEM_write_RSAPublicKey failed");
389 		break;
390 	case KEY_DSA:
391 		if (!PEM_write_DSA_PUBKEY(stdout, k->dsa))
392 			fatal("PEM_write_DSA_PUBKEY failed");
393 		break;
394 	case KEY_ECDSA:
395 		if (!PEM_write_EC_PUBKEY(stdout, k->ecdsa))
396 			fatal("PEM_write_EC_PUBKEY failed");
397 		break;
398 	default:
399 		fatal_f("unsupported key type %s", sshkey_type(k));
400 	}
401 	exit(0);
402 }
403 
404 static void
405 do_convert_to(struct passwd *pw)
406 {
407 	struct sshkey *k;
408 	struct stat st;
409 	int r;
410 
411 	if (!have_identity)
412 		ask_filename(pw, "Enter file in which the key is");
413 	if (stat(identity_file, &st) == -1)
414 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
415 	if ((r = sshkey_load_public(identity_file, &k, NULL)) != 0)
416 		k = load_identity(identity_file, NULL);
417 	switch (convert_format) {
418 	case FMT_RFC4716:
419 		do_convert_to_ssh2(pw, k);
420 		break;
421 	case FMT_PKCS8:
422 		do_convert_to_pkcs8(k);
423 		break;
424 	case FMT_PEM:
425 		do_convert_to_pem(k);
426 		break;
427 	default:
428 		fatal_f("unknown key format %d", convert_format);
429 	}
430 	exit(0);
431 }
432 
433 /*
434  * This is almost exactly the bignum1 encoding, but with 32 bit for length
435  * instead of 16.
436  */
437 static void
438 buffer_get_bignum_bits(struct sshbuf *b, BIGNUM *value)
439 {
440 	u_int bytes, bignum_bits;
441 	int r;
442 
443 	if ((r = sshbuf_get_u32(b, &bignum_bits)) != 0)
444 		fatal_fr(r, "parse");
445 	bytes = (bignum_bits + 7) / 8;
446 	if (sshbuf_len(b) < bytes)
447 		fatal_f("input buffer too small: need %d have %zu",
448 		    bytes, sshbuf_len(b));
449 	if (BN_bin2bn(sshbuf_ptr(b), bytes, value) == NULL)
450 		fatal_f("BN_bin2bn failed");
451 	if ((r = sshbuf_consume(b, bytes)) != 0)
452 		fatal_fr(r, "consume");
453 }
454 
455 static struct sshkey *
456 do_convert_private_ssh2(struct sshbuf *b)
457 {
458 	struct sshkey *key = NULL;
459 	char *type, *cipher;
460 	u_char e1, e2, e3, *sig = NULL, data[] = "abcde12345";
461 	int r, rlen, ktype;
462 	u_int magic, i1, i2, i3, i4;
463 	size_t slen;
464 	u_long e;
465 	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL;
466 	BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL;
467 	BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL;
468 	BIGNUM *rsa_p = NULL, *rsa_q = NULL, *rsa_iqmp = NULL;
469 
470 	if ((r = sshbuf_get_u32(b, &magic)) != 0)
471 		fatal_fr(r, "parse magic");
472 
473 	if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
474 		error("bad magic 0x%x != 0x%x", magic,
475 		    SSH_COM_PRIVATE_KEY_MAGIC);
476 		return NULL;
477 	}
478 	if ((r = sshbuf_get_u32(b, &i1)) != 0 ||
479 	    (r = sshbuf_get_cstring(b, &type, NULL)) != 0 ||
480 	    (r = sshbuf_get_cstring(b, &cipher, NULL)) != 0 ||
481 	    (r = sshbuf_get_u32(b, &i2)) != 0 ||
482 	    (r = sshbuf_get_u32(b, &i3)) != 0 ||
483 	    (r = sshbuf_get_u32(b, &i4)) != 0)
484 		fatal_fr(r, "parse");
485 	debug("ignore (%d %d %d %d)", i1, i2, i3, i4);
486 	if (strcmp(cipher, "none") != 0) {
487 		error("unsupported cipher %s", cipher);
488 		free(cipher);
489 		free(type);
490 		return NULL;
491 	}
492 	free(cipher);
493 
494 	if (strstr(type, "dsa")) {
495 		ktype = KEY_DSA;
496 	} else if (strstr(type, "rsa")) {
497 		ktype = KEY_RSA;
498 	} else {
499 		free(type);
500 		return NULL;
501 	}
502 	if ((key = sshkey_new(ktype)) == NULL)
503 		fatal("sshkey_new failed");
504 	free(type);
505 
506 	switch (key->type) {
507 	case KEY_DSA:
508 		if ((dsa_p = BN_new()) == NULL ||
509 		    (dsa_q = BN_new()) == NULL ||
510 		    (dsa_g = BN_new()) == NULL ||
511 		    (dsa_pub_key = BN_new()) == NULL ||
512 		    (dsa_priv_key = BN_new()) == NULL)
513 			fatal_f("BN_new");
514 		buffer_get_bignum_bits(b, dsa_p);
515 		buffer_get_bignum_bits(b, dsa_g);
516 		buffer_get_bignum_bits(b, dsa_q);
517 		buffer_get_bignum_bits(b, dsa_pub_key);
518 		buffer_get_bignum_bits(b, dsa_priv_key);
519 		if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g))
520 			fatal_f("DSA_set0_pqg failed");
521 		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
522 		if (!DSA_set0_key(key->dsa, dsa_pub_key, dsa_priv_key))
523 			fatal_f("DSA_set0_key failed");
524 		dsa_pub_key = dsa_priv_key = NULL; /* transferred */
525 		break;
526 	case KEY_RSA:
527 		if ((r = sshbuf_get_u8(b, &e1)) != 0 ||
528 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e2)) != 0) ||
529 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e3)) != 0))
530 			fatal_fr(r, "parse RSA");
531 		e = e1;
532 		debug("e %lx", e);
533 		if (e < 30) {
534 			e <<= 8;
535 			e += e2;
536 			debug("e %lx", e);
537 			e <<= 8;
538 			e += e3;
539 			debug("e %lx", e);
540 		}
541 		if ((rsa_e = BN_new()) == NULL)
542 			fatal_f("BN_new");
543 		if (!BN_set_word(rsa_e, e)) {
544 			BN_clear_free(rsa_e);
545 			sshkey_free(key);
546 			return NULL;
547 		}
548 		if ((rsa_n = BN_new()) == NULL ||
549 		    (rsa_d = BN_new()) == NULL ||
550 		    (rsa_p = BN_new()) == NULL ||
551 		    (rsa_q = BN_new()) == NULL ||
552 		    (rsa_iqmp = BN_new()) == NULL)
553 			fatal_f("BN_new");
554 		buffer_get_bignum_bits(b, rsa_d);
555 		buffer_get_bignum_bits(b, rsa_n);
556 		buffer_get_bignum_bits(b, rsa_iqmp);
557 		buffer_get_bignum_bits(b, rsa_q);
558 		buffer_get_bignum_bits(b, rsa_p);
559 		if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, rsa_d))
560 			fatal_f("RSA_set0_key failed");
561 		rsa_n = rsa_e = rsa_d = NULL; /* transferred */
562 		if (!RSA_set0_factors(key->rsa, rsa_p, rsa_q))
563 			fatal_f("RSA_set0_factors failed");
564 		rsa_p = rsa_q = NULL; /* transferred */
565 		if ((r = ssh_rsa_complete_crt_parameters(key, rsa_iqmp)) != 0)
566 			fatal_fr(r, "generate RSA parameters");
567 		BN_clear_free(rsa_iqmp);
568 		break;
569 	}
570 	rlen = sshbuf_len(b);
571 	if (rlen != 0)
572 		error_f("remaining bytes in key blob %d", rlen);
573 
574 	/* try the key */
575 	if (sshkey_sign(key, &sig, &slen, data, sizeof(data),
576 	    NULL, NULL, NULL, 0) != 0 ||
577 	    sshkey_verify(key, sig, slen, data, sizeof(data),
578 	    NULL, 0, NULL) != 0) {
579 		sshkey_free(key);
580 		free(sig);
581 		return NULL;
582 	}
583 	free(sig);
584 	return key;
585 }
586 
587 static int
588 get_line(FILE *fp, char *line, size_t len)
589 {
590 	int c;
591 	size_t pos = 0;
592 
593 	line[0] = '\0';
594 	while ((c = fgetc(fp)) != EOF) {
595 		if (pos >= len - 1)
596 			fatal("input line too long.");
597 		switch (c) {
598 		case '\r':
599 			c = fgetc(fp);
600 			if (c != EOF && c != '\n' && ungetc(c, fp) == EOF)
601 				fatal("unget: %s", strerror(errno));
602 			return pos;
603 		case '\n':
604 			return pos;
605 		}
606 		line[pos++] = c;
607 		line[pos] = '\0';
608 	}
609 	/* We reached EOF */
610 	return -1;
611 }
612 
613 static void
614 do_convert_from_ssh2(struct passwd *pw, struct sshkey **k, int *private)
615 {
616 	int r, blen, escaped = 0;
617 	u_int len;
618 	char line[1024];
619 	struct sshbuf *buf;
620 	char encoded[8096];
621 	FILE *fp;
622 
623 	if ((buf = sshbuf_new()) == NULL)
624 		fatal("sshbuf_new failed");
625 	if ((fp = fopen(identity_file, "r")) == NULL)
626 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
627 	encoded[0] = '\0';
628 	while ((blen = get_line(fp, line, sizeof(line))) != -1) {
629 		if (blen > 0 && line[blen - 1] == '\\')
630 			escaped++;
631 		if (strncmp(line, "----", 4) == 0 ||
632 		    strstr(line, ": ") != NULL) {
633 			if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
634 				*private = 1;
635 			if (strstr(line, " END ") != NULL) {
636 				break;
637 			}
638 			/* fprintf(stderr, "ignore: %s", line); */
639 			continue;
640 		}
641 		if (escaped) {
642 			escaped--;
643 			/* fprintf(stderr, "escaped: %s", line); */
644 			continue;
645 		}
646 		strlcat(encoded, line, sizeof(encoded));
647 	}
648 	len = strlen(encoded);
649 	if (((len % 4) == 3) &&
650 	    (encoded[len-1] == '=') &&
651 	    (encoded[len-2] == '=') &&
652 	    (encoded[len-3] == '='))
653 		encoded[len-3] = '\0';
654 	if ((r = sshbuf_b64tod(buf, encoded)) != 0)
655 		fatal_fr(r, "base64 decode");
656 	if (*private) {
657 		if ((*k = do_convert_private_ssh2(buf)) == NULL)
658 			fatal_f("private key conversion failed");
659 	} else if ((r = sshkey_fromb(buf, k)) != 0)
660 		fatal_fr(r, "parse key");
661 	sshbuf_free(buf);
662 	fclose(fp);
663 }
664 
665 static void
666 do_convert_from_pkcs8(struct sshkey **k, int *private)
667 {
668 	EVP_PKEY *pubkey;
669 	FILE *fp;
670 
671 	if ((fp = fopen(identity_file, "r")) == NULL)
672 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
673 	if ((pubkey = PEM_read_PUBKEY(fp, NULL, NULL, NULL)) == NULL) {
674 		fatal_f("%s is not a recognised public key format",
675 		    identity_file);
676 	}
677 	fclose(fp);
678 	switch (EVP_PKEY_base_id(pubkey)) {
679 	case EVP_PKEY_RSA:
680 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
681 			fatal("sshkey_new failed");
682 		(*k)->type = KEY_RSA;
683 		(*k)->rsa = EVP_PKEY_get1_RSA(pubkey);
684 		break;
685 	case EVP_PKEY_DSA:
686 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
687 			fatal("sshkey_new failed");
688 		(*k)->type = KEY_DSA;
689 		(*k)->dsa = EVP_PKEY_get1_DSA(pubkey);
690 		break;
691 	case EVP_PKEY_EC:
692 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
693 			fatal("sshkey_new failed");
694 		(*k)->type = KEY_ECDSA;
695 		(*k)->ecdsa = EVP_PKEY_get1_EC_KEY(pubkey);
696 		(*k)->ecdsa_nid = sshkey_ecdsa_key_to_nid((*k)->ecdsa);
697 		break;
698 	default:
699 		fatal_f("unsupported pubkey type %d",
700 		    EVP_PKEY_base_id(pubkey));
701 	}
702 	EVP_PKEY_free(pubkey);
703 	return;
704 }
705 
706 static void
707 do_convert_from_pem(struct sshkey **k, int *private)
708 {
709 	FILE *fp;
710 	RSA *rsa;
711 
712 	if ((fp = fopen(identity_file, "r")) == NULL)
713 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
714 	if ((rsa = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL)) != NULL) {
715 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
716 			fatal("sshkey_new failed");
717 		(*k)->type = KEY_RSA;
718 		(*k)->rsa = rsa;
719 		fclose(fp);
720 		return;
721 	}
722 	fatal_f("unrecognised raw private key format");
723 }
724 
725 static void
726 do_convert_from(struct passwd *pw)
727 {
728 	struct sshkey *k = NULL;
729 	int r, private = 0, ok = 0;
730 	struct stat st;
731 
732 	if (!have_identity)
733 		ask_filename(pw, "Enter file in which the key is");
734 	if (stat(identity_file, &st) == -1)
735 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
736 
737 	switch (convert_format) {
738 	case FMT_RFC4716:
739 		do_convert_from_ssh2(pw, &k, &private);
740 		break;
741 	case FMT_PKCS8:
742 		do_convert_from_pkcs8(&k, &private);
743 		break;
744 	case FMT_PEM:
745 		do_convert_from_pem(&k, &private);
746 		break;
747 	default:
748 		fatal_f("unknown key format %d", convert_format);
749 	}
750 
751 	if (!private) {
752 		if ((r = sshkey_write(k, stdout)) == 0)
753 			ok = 1;
754 		if (ok)
755 			fprintf(stdout, "\n");
756 	} else {
757 		switch (k->type) {
758 		case KEY_DSA:
759 			ok = PEM_write_DSAPrivateKey(stdout, k->dsa, NULL,
760 			    NULL, 0, NULL, NULL);
761 			break;
762 		case KEY_ECDSA:
763 			ok = PEM_write_ECPrivateKey(stdout, k->ecdsa, NULL,
764 			    NULL, 0, NULL, NULL);
765 			break;
766 		case KEY_RSA:
767 			ok = PEM_write_RSAPrivateKey(stdout, k->rsa, NULL,
768 			    NULL, 0, NULL, NULL);
769 			break;
770 		default:
771 			fatal_f("unsupported key type %s", sshkey_type(k));
772 		}
773 	}
774 
775 	if (!ok)
776 		fatal("key write failed");
777 	sshkey_free(k);
778 	exit(0);
779 }
780 #endif
781 
782 static void
783 do_print_public(struct passwd *pw)
784 {
785 	struct sshkey *prv;
786 	struct stat st;
787 	int r;
788 	char *comment = NULL;
789 
790 	if (!have_identity)
791 		ask_filename(pw, "Enter file in which the key is");
792 	if (stat(identity_file, &st) == -1)
793 		fatal("%s: %s", identity_file, strerror(errno));
794 	prv = load_identity(identity_file, &comment);
795 	if ((r = sshkey_write(prv, stdout)) != 0)
796 		fatal_fr(r, "write key");
797 	if (comment != NULL && *comment != '\0')
798 		fprintf(stdout, " %s", comment);
799 	fprintf(stdout, "\n");
800 	if (sshkey_is_sk(prv)) {
801 		debug("sk_application: \"%s\", sk_flags 0x%02x",
802 			prv->sk_application, prv->sk_flags);
803 	}
804 	sshkey_free(prv);
805 	free(comment);
806 	exit(0);
807 }
808 
809 static void
810 do_download(struct passwd *pw)
811 {
812 #ifdef ENABLE_PKCS11
813 	struct sshkey **keys = NULL;
814 	int i, nkeys;
815 	enum sshkey_fp_rep rep;
816 	int fptype;
817 	char *fp, *ra, **comments = NULL;
818 
819 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
820 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
821 
822 	pkcs11_init(1);
823 	nkeys = pkcs11_add_provider(pkcs11provider, NULL, &keys, &comments);
824 	if (nkeys <= 0)
825 		fatal("cannot read public key from pkcs11");
826 	for (i = 0; i < nkeys; i++) {
827 		if (print_fingerprint) {
828 			fp = sshkey_fingerprint(keys[i], fptype, rep);
829 			ra = sshkey_fingerprint(keys[i], fingerprint_hash,
830 			    SSH_FP_RANDOMART);
831 			if (fp == NULL || ra == NULL)
832 				fatal_f("sshkey_fingerprint fail");
833 			printf("%u %s %s (PKCS11 key)\n", sshkey_size(keys[i]),
834 			    fp, sshkey_type(keys[i]));
835 			if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
836 				printf("%s\n", ra);
837 			free(ra);
838 			free(fp);
839 		} else {
840 			(void) sshkey_write(keys[i], stdout); /* XXX check */
841 			fprintf(stdout, "%s%s\n",
842 			    *(comments[i]) == '\0' ? "" : " ", comments[i]);
843 		}
844 		free(comments[i]);
845 		sshkey_free(keys[i]);
846 	}
847 	free(comments);
848 	free(keys);
849 	pkcs11_terminate();
850 	exit(0);
851 #else
852 	fatal("no pkcs11 support");
853 #endif /* ENABLE_PKCS11 */
854 }
855 
856 static struct sshkey *
857 try_read_key(char **cpp)
858 {
859 	struct sshkey *ret;
860 	int r;
861 
862 	if ((ret = sshkey_new(KEY_UNSPEC)) == NULL)
863 		fatal("sshkey_new failed");
864 	if ((r = sshkey_read(ret, cpp)) == 0)
865 		return ret;
866 	/* Not a key */
867 	sshkey_free(ret);
868 	return NULL;
869 }
870 
871 static void
872 fingerprint_one_key(const struct sshkey *public, const char *comment)
873 {
874 	char *fp = NULL, *ra = NULL;
875 	enum sshkey_fp_rep rep;
876 	int fptype;
877 
878 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
879 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
880 	fp = sshkey_fingerprint(public, fptype, rep);
881 	ra = sshkey_fingerprint(public, fingerprint_hash, SSH_FP_RANDOMART);
882 	if (fp == NULL || ra == NULL)
883 		fatal_f("sshkey_fingerprint failed");
884 	mprintf("%u %s %s (%s)\n", sshkey_size(public), fp,
885 	    comment ? comment : "no comment", sshkey_type(public));
886 	if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
887 		printf("%s\n", ra);
888 	free(ra);
889 	free(fp);
890 }
891 
892 static void
893 fingerprint_private(const char *path)
894 {
895 	struct stat st;
896 	char *comment = NULL;
897 	struct sshkey *privkey = NULL, *pubkey = NULL;
898 	int r;
899 
900 	if (stat(identity_file, &st) == -1)
901 		fatal("%s: %s", path, strerror(errno));
902 	if ((r = sshkey_load_public(path, &pubkey, &comment)) != 0)
903 		debug_r(r, "load public \"%s\"", path);
904 	if (pubkey == NULL || comment == NULL || *comment == '\0') {
905 		free(comment);
906 		if ((r = sshkey_load_private(path, NULL,
907 		    &privkey, &comment)) != 0)
908 			debug_r(r, "load private \"%s\"", path);
909 	}
910 	if (pubkey == NULL && privkey == NULL)
911 		fatal("%s is not a key file.", path);
912 
913 	fingerprint_one_key(pubkey == NULL ? privkey : pubkey, comment);
914 	sshkey_free(pubkey);
915 	sshkey_free(privkey);
916 	free(comment);
917 }
918 
919 static void
920 do_fingerprint(struct passwd *pw)
921 {
922 	FILE *f;
923 	struct sshkey *public = NULL;
924 	char *comment = NULL, *cp, *ep, *line = NULL;
925 	size_t linesize = 0;
926 	int i, invalid = 1;
927 	const char *path;
928 	u_long lnum = 0;
929 
930 	if (!have_identity)
931 		ask_filename(pw, "Enter file in which the key is");
932 	path = identity_file;
933 
934 	if (strcmp(identity_file, "-") == 0) {
935 		f = stdin;
936 		path = "(stdin)";
937 	} else if ((f = fopen(path, "r")) == NULL)
938 		fatal("%s: %s: %s", __progname, path, strerror(errno));
939 
940 	while (getline(&line, &linesize, f) != -1) {
941 		lnum++;
942 		cp = line;
943 		cp[strcspn(cp, "\n")] = '\0';
944 		/* Trim leading space and comments */
945 		cp = line + strspn(line, " \t");
946 		if (*cp == '#' || *cp == '\0')
947 			continue;
948 
949 		/*
950 		 * Input may be plain keys, private keys, authorized_keys
951 		 * or known_hosts.
952 		 */
953 
954 		/*
955 		 * Try private keys first. Assume a key is private if
956 		 * "SSH PRIVATE KEY" appears on the first line and we're
957 		 * not reading from stdin (XXX support private keys on stdin).
958 		 */
959 		if (lnum == 1 && strcmp(identity_file, "-") != 0 &&
960 		    strstr(cp, "PRIVATE KEY") != NULL) {
961 			free(line);
962 			fclose(f);
963 			fingerprint_private(path);
964 			exit(0);
965 		}
966 
967 		/*
968 		 * If it's not a private key, then this must be prepared to
969 		 * accept a public key prefixed with a hostname or options.
970 		 * Try a bare key first, otherwise skip the leading stuff.
971 		 */
972 		if ((public = try_read_key(&cp)) == NULL) {
973 			i = strtol(cp, &ep, 10);
974 			if (i == 0 || ep == NULL ||
975 			    (*ep != ' ' && *ep != '\t')) {
976 				int quoted = 0;
977 
978 				comment = cp;
979 				for (; *cp && (quoted || (*cp != ' ' &&
980 				    *cp != '\t')); cp++) {
981 					if (*cp == '\\' && cp[1] == '"')
982 						cp++;	/* Skip both */
983 					else if (*cp == '"')
984 						quoted = !quoted;
985 				}
986 				if (!*cp)
987 					continue;
988 				*cp++ = '\0';
989 			}
990 		}
991 		/* Retry after parsing leading hostname/key options */
992 		if (public == NULL && (public = try_read_key(&cp)) == NULL) {
993 			debug("%s:%lu: not a public key", path, lnum);
994 			continue;
995 		}
996 
997 		/* Find trailing comment, if any */
998 		for (; *cp == ' ' || *cp == '\t'; cp++)
999 			;
1000 		if (*cp != '\0' && *cp != '#')
1001 			comment = cp;
1002 
1003 		fingerprint_one_key(public, comment);
1004 		sshkey_free(public);
1005 		invalid = 0; /* One good key in the file is sufficient */
1006 	}
1007 	fclose(f);
1008 	free(line);
1009 
1010 	if (invalid)
1011 		fatal("%s is not a public key file.", path);
1012 	exit(0);
1013 }
1014 
1015 static void
1016 do_gen_all_hostkeys(struct passwd *pw)
1017 {
1018 	struct {
1019 		char *key_type;
1020 		char *key_type_display;
1021 		char *path;
1022 	} key_types[] = {
1023 #ifdef WITH_OPENSSL
1024 		{ "rsa", "RSA" ,_PATH_HOST_RSA_KEY_FILE },
1025 		{ "dsa", "DSA", _PATH_HOST_DSA_KEY_FILE },
1026 		{ "ecdsa", "ECDSA",_PATH_HOST_ECDSA_KEY_FILE },
1027 #endif /* WITH_OPENSSL */
1028 		{ "ed25519", "ED25519",_PATH_HOST_ED25519_KEY_FILE },
1029 #ifdef WITH_XMSS
1030 		{ "xmss", "XMSS",_PATH_HOST_XMSS_KEY_FILE },
1031 #endif /* WITH_XMSS */
1032 		{ NULL, NULL, NULL }
1033 	};
1034 
1035 	u_int32_t bits = 0;
1036 	int first = 0;
1037 	struct stat st;
1038 	struct sshkey *private, *public;
1039 	char comment[1024], *prv_tmp, *pub_tmp, *prv_file, *pub_file;
1040 	int i, type, fd, r;
1041 
1042 	for (i = 0; key_types[i].key_type; i++) {
1043 		public = private = NULL;
1044 		prv_tmp = pub_tmp = prv_file = pub_file = NULL;
1045 
1046 		xasprintf(&prv_file, "%s%s",
1047 		    identity_file, key_types[i].path);
1048 
1049 		/* Check whether private key exists and is not zero-length */
1050 		if (stat(prv_file, &st) == 0) {
1051 			if (st.st_size != 0)
1052 				goto next;
1053 		} else if (errno != ENOENT) {
1054 			error("Could not stat %s: %s", key_types[i].path,
1055 			    strerror(errno));
1056 			goto failnext;
1057 		}
1058 
1059 		/*
1060 		 * Private key doesn't exist or is invalid; proceed with
1061 		 * key generation.
1062 		 */
1063 		xasprintf(&prv_tmp, "%s%s.XXXXXXXXXX",
1064 		    identity_file, key_types[i].path);
1065 		xasprintf(&pub_tmp, "%s%s.pub.XXXXXXXXXX",
1066 		    identity_file, key_types[i].path);
1067 		xasprintf(&pub_file, "%s%s.pub",
1068 		    identity_file, key_types[i].path);
1069 
1070 		if (first == 0) {
1071 			first = 1;
1072 			printf("%s: generating new host keys: ", __progname);
1073 		}
1074 		printf("%s ", key_types[i].key_type_display);
1075 		fflush(stdout);
1076 		type = sshkey_type_from_name(key_types[i].key_type);
1077 		if ((fd = mkstemp(prv_tmp)) == -1) {
1078 			error("Could not save your private key in %s: %s",
1079 			    prv_tmp, strerror(errno));
1080 			goto failnext;
1081 		}
1082 		(void)close(fd); /* just using mkstemp() to reserve a name */
1083 		bits = 0;
1084 		type_bits_valid(type, NULL, &bits);
1085 		if ((r = sshkey_generate(type, bits, &private)) != 0) {
1086 			error_r(r, "sshkey_generate failed");
1087 			goto failnext;
1088 		}
1089 		if ((r = sshkey_from_private(private, &public)) != 0)
1090 			fatal_fr(r, "sshkey_from_private");
1091 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name,
1092 		    hostname);
1093 		if ((r = sshkey_save_private(private, prv_tmp, "",
1094 		    comment, private_key_format, openssh_format_cipher,
1095 		    rounds)) != 0) {
1096 			error_r(r, "Saving key \"%s\" failed", prv_tmp);
1097 			goto failnext;
1098 		}
1099 		if ((fd = mkstemp(pub_tmp)) == -1) {
1100 			error("Could not save your public key in %s: %s",
1101 			    pub_tmp, strerror(errno));
1102 			goto failnext;
1103 		}
1104 		(void)fchmod(fd, 0644);
1105 		(void)close(fd);
1106 		if ((r = sshkey_save_public(public, pub_tmp, comment)) != 0) {
1107 			error_r(r, "Unable to save public key to %s",
1108 			    identity_file);
1109 			goto failnext;
1110 		}
1111 
1112 		/* Rename temporary files to their permanent locations. */
1113 		if (rename(pub_tmp, pub_file) != 0) {
1114 			error("Unable to move %s into position: %s",
1115 			    pub_file, strerror(errno));
1116 			goto failnext;
1117 		}
1118 		if (rename(prv_tmp, prv_file) != 0) {
1119 			error("Unable to move %s into position: %s",
1120 			    key_types[i].path, strerror(errno));
1121  failnext:
1122 			first = 0;
1123 			goto next;
1124 		}
1125  next:
1126 		sshkey_free(private);
1127 		sshkey_free(public);
1128 		free(prv_tmp);
1129 		free(pub_tmp);
1130 		free(prv_file);
1131 		free(pub_file);
1132 	}
1133 	if (first != 0)
1134 		printf("\n");
1135 }
1136 
1137 struct known_hosts_ctx {
1138 	const char *host;	/* Hostname searched for in find/delete case */
1139 	FILE *out;		/* Output file, stdout for find_hosts case */
1140 	int has_unhashed;	/* When hashing, original had unhashed hosts */
1141 	int found_key;		/* For find/delete, host was found */
1142 	int invalid;		/* File contained invalid items; don't delete */
1143 	int hash_hosts;		/* Hash hostnames as we go */
1144 	int find_host;		/* Search for specific hostname */
1145 	int delete_host;	/* Delete host from known_hosts */
1146 };
1147 
1148 static int
1149 known_hosts_hash(struct hostkey_foreach_line *l, void *_ctx)
1150 {
1151 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1152 	char *hashed, *cp, *hosts, *ohosts;
1153 	int has_wild = l->hosts && strcspn(l->hosts, "*?!") != strlen(l->hosts);
1154 	int was_hashed = l->hosts && l->hosts[0] == HASH_DELIM;
1155 
1156 	switch (l->status) {
1157 	case HKF_STATUS_OK:
1158 	case HKF_STATUS_MATCHED:
1159 		/*
1160 		 * Don't hash hosts already already hashed, with wildcard
1161 		 * characters or a CA/revocation marker.
1162 		 */
1163 		if (was_hashed || has_wild || l->marker != MRK_NONE) {
1164 			fprintf(ctx->out, "%s\n", l->line);
1165 			if (has_wild && !ctx->find_host) {
1166 				logit("%s:%lu: ignoring host name "
1167 				    "with wildcard: %.64s", l->path,
1168 				    l->linenum, l->hosts);
1169 			}
1170 			return 0;
1171 		}
1172 		/*
1173 		 * Split any comma-separated hostnames from the host list,
1174 		 * hash and store separately.
1175 		 */
1176 		ohosts = hosts = xstrdup(l->hosts);
1177 		while ((cp = strsep(&hosts, ",")) != NULL && *cp != '\0') {
1178 			lowercase(cp);
1179 			if ((hashed = host_hash(cp, NULL, 0)) == NULL)
1180 				fatal("hash_host failed");
1181 			fprintf(ctx->out, "%s %s\n", hashed, l->rawkey);
1182 			ctx->has_unhashed = 1;
1183 		}
1184 		free(ohosts);
1185 		return 0;
1186 	case HKF_STATUS_INVALID:
1187 		/* Retain invalid lines, but mark file as invalid. */
1188 		ctx->invalid = 1;
1189 		logit("%s:%lu: invalid line", l->path, l->linenum);
1190 		/* FALLTHROUGH */
1191 	default:
1192 		fprintf(ctx->out, "%s\n", l->line);
1193 		return 0;
1194 	}
1195 	/* NOTREACHED */
1196 	return -1;
1197 }
1198 
1199 static int
1200 known_hosts_find_delete(struct hostkey_foreach_line *l, void *_ctx)
1201 {
1202 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1203 	enum sshkey_fp_rep rep;
1204 	int fptype;
1205 	char *fp = NULL, *ra = NULL;
1206 
1207 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
1208 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
1209 
1210 	if (l->status == HKF_STATUS_MATCHED) {
1211 		if (ctx->delete_host) {
1212 			if (l->marker != MRK_NONE) {
1213 				/* Don't remove CA and revocation lines */
1214 				fprintf(ctx->out, "%s\n", l->line);
1215 			} else {
1216 				/*
1217 				 * Hostname matches and has no CA/revoke
1218 				 * marker, delete it by *not* writing the
1219 				 * line to ctx->out.
1220 				 */
1221 				ctx->found_key = 1;
1222 				if (!quiet)
1223 					printf("# Host %s found: line %lu\n",
1224 					    ctx->host, l->linenum);
1225 			}
1226 			return 0;
1227 		} else if (ctx->find_host) {
1228 			ctx->found_key = 1;
1229 			if (!quiet) {
1230 				printf("# Host %s found: line %lu %s\n",
1231 				    ctx->host,
1232 				    l->linenum, l->marker == MRK_CA ? "CA" :
1233 				    (l->marker == MRK_REVOKE ? "REVOKED" : ""));
1234 			}
1235 			if (ctx->hash_hosts)
1236 				known_hosts_hash(l, ctx);
1237 			else if (print_fingerprint) {
1238 				fp = sshkey_fingerprint(l->key, fptype, rep);
1239 				ra = sshkey_fingerprint(l->key,
1240 				    fingerprint_hash, SSH_FP_RANDOMART);
1241 				if (fp == NULL || ra == NULL)
1242 					fatal_f("sshkey_fingerprint failed");
1243 				mprintf("%s %s %s%s%s\n", ctx->host,
1244 				    sshkey_type(l->key), fp,
1245 				    l->comment[0] ? " " : "",
1246 				    l->comment);
1247 				if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
1248 					printf("%s\n", ra);
1249 				free(ra);
1250 				free(fp);
1251 			} else
1252 				fprintf(ctx->out, "%s\n", l->line);
1253 			return 0;
1254 		}
1255 	} else if (ctx->delete_host) {
1256 		/* Retain non-matching hosts when deleting */
1257 		if (l->status == HKF_STATUS_INVALID) {
1258 			ctx->invalid = 1;
1259 			logit("%s:%lu: invalid line", l->path, l->linenum);
1260 		}
1261 		fprintf(ctx->out, "%s\n", l->line);
1262 	}
1263 	return 0;
1264 }
1265 
1266 static void
1267 do_known_hosts(struct passwd *pw, const char *name, int find_host,
1268     int delete_host, int hash_hosts)
1269 {
1270 	char *cp, tmp[PATH_MAX], old[PATH_MAX];
1271 	int r, fd, oerrno, inplace = 0;
1272 	struct known_hosts_ctx ctx;
1273 	u_int foreach_options;
1274 	struct stat sb;
1275 
1276 	if (!have_identity) {
1277 		cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
1278 		if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
1279 		    sizeof(identity_file))
1280 			fatal("Specified known hosts path too long");
1281 		free(cp);
1282 		have_identity = 1;
1283 	}
1284 	if (stat(identity_file, &sb) != 0)
1285 		fatal("Cannot stat %s: %s", identity_file, strerror(errno));
1286 
1287 	memset(&ctx, 0, sizeof(ctx));
1288 	ctx.out = stdout;
1289 	ctx.host = name;
1290 	ctx.hash_hosts = hash_hosts;
1291 	ctx.find_host = find_host;
1292 	ctx.delete_host = delete_host;
1293 
1294 	/*
1295 	 * Find hosts goes to stdout, hash and deletions happen in-place
1296 	 * A corner case is ssh-keygen -HF foo, which should go to stdout
1297 	 */
1298 	if (!find_host && (hash_hosts || delete_host)) {
1299 		if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
1300 		    strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
1301 		    strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
1302 		    strlcat(old, ".old", sizeof(old)) >= sizeof(old))
1303 			fatal("known_hosts path too long");
1304 		umask(077);
1305 		if ((fd = mkstemp(tmp)) == -1)
1306 			fatal("mkstemp: %s", strerror(errno));
1307 		if ((ctx.out = fdopen(fd, "w")) == NULL) {
1308 			oerrno = errno;
1309 			unlink(tmp);
1310 			fatal("fdopen: %s", strerror(oerrno));
1311 		}
1312 		fchmod(fd, sb.st_mode & 0644);
1313 		inplace = 1;
1314 	}
1315 	/* XXX support identity_file == "-" for stdin */
1316 	foreach_options = find_host ? HKF_WANT_MATCH : 0;
1317 	foreach_options |= print_fingerprint ? HKF_WANT_PARSE_KEY : 0;
1318 	if ((r = hostkeys_foreach(identity_file, (find_host || !hash_hosts) ?
1319 	    known_hosts_find_delete : known_hosts_hash, &ctx, name, NULL,
1320 	    foreach_options)) != 0) {
1321 		if (inplace)
1322 			unlink(tmp);
1323 		fatal_fr(r, "hostkeys_foreach");
1324 	}
1325 
1326 	if (inplace)
1327 		fclose(ctx.out);
1328 
1329 	if (ctx.invalid) {
1330 		error("%s is not a valid known_hosts file.", identity_file);
1331 		if (inplace) {
1332 			error("Not replacing existing known_hosts "
1333 			    "file because of errors");
1334 			unlink(tmp);
1335 		}
1336 		exit(1);
1337 	} else if (delete_host && !ctx.found_key) {
1338 		logit("Host %s not found in %s", name, identity_file);
1339 		if (inplace)
1340 			unlink(tmp);
1341 	} else if (inplace) {
1342 		/* Backup existing file */
1343 		if (unlink(old) == -1 && errno != ENOENT)
1344 			fatal("unlink %.100s: %s", old, strerror(errno));
1345 		if (link(identity_file, old) == -1)
1346 			fatal("link %.100s to %.100s: %s", identity_file, old,
1347 			    strerror(errno));
1348 		/* Move new one into place */
1349 		if (rename(tmp, identity_file) == -1) {
1350 			error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
1351 			    strerror(errno));
1352 			unlink(tmp);
1353 			unlink(old);
1354 			exit(1);
1355 		}
1356 
1357 		printf("%s updated.\n", identity_file);
1358 		printf("Original contents retained as %s\n", old);
1359 		if (ctx.has_unhashed) {
1360 			logit("WARNING: %s contains unhashed entries", old);
1361 			logit("Delete this file to ensure privacy "
1362 			    "of hostnames");
1363 		}
1364 	}
1365 
1366 	exit (find_host && !ctx.found_key);
1367 }
1368 
1369 /*
1370  * Perform changing a passphrase.  The argument is the passwd structure
1371  * for the current user.
1372  */
1373 static void
1374 do_change_passphrase(struct passwd *pw)
1375 {
1376 	char *comment;
1377 	char *old_passphrase, *passphrase1, *passphrase2;
1378 	struct stat st;
1379 	struct sshkey *private;
1380 	int r;
1381 
1382 	if (!have_identity)
1383 		ask_filename(pw, "Enter file in which the key is");
1384 	if (stat(identity_file, &st) == -1)
1385 		fatal("%s: %s", identity_file, strerror(errno));
1386 	/* Try to load the file with empty passphrase. */
1387 	r = sshkey_load_private(identity_file, "", &private, &comment);
1388 	if (r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1389 		if (identity_passphrase)
1390 			old_passphrase = xstrdup(identity_passphrase);
1391 		else
1392 			old_passphrase =
1393 			    read_passphrase("Enter old passphrase: ",
1394 			    RP_ALLOW_STDIN);
1395 		r = sshkey_load_private(identity_file, old_passphrase,
1396 		    &private, &comment);
1397 		freezero(old_passphrase, strlen(old_passphrase));
1398 		if (r != 0)
1399 			goto badkey;
1400 	} else if (r != 0) {
1401  badkey:
1402 		fatal_r(r, "Failed to load key %s", identity_file);
1403 	}
1404 	if (comment)
1405 		mprintf("Key has comment '%s'\n", comment);
1406 
1407 	/* Ask the new passphrase (twice). */
1408 	if (identity_new_passphrase) {
1409 		passphrase1 = xstrdup(identity_new_passphrase);
1410 		passphrase2 = NULL;
1411 	} else {
1412 		passphrase1 =
1413 			read_passphrase("Enter new passphrase (empty for no "
1414 			    "passphrase): ", RP_ALLOW_STDIN);
1415 		passphrase2 = read_passphrase("Enter same passphrase again: ",
1416 		    RP_ALLOW_STDIN);
1417 
1418 		/* Verify that they are the same. */
1419 		if (strcmp(passphrase1, passphrase2) != 0) {
1420 			explicit_bzero(passphrase1, strlen(passphrase1));
1421 			explicit_bzero(passphrase2, strlen(passphrase2));
1422 			free(passphrase1);
1423 			free(passphrase2);
1424 			printf("Pass phrases do not match.  Try again.\n");
1425 			exit(1);
1426 		}
1427 		/* Destroy the other copy. */
1428 		freezero(passphrase2, strlen(passphrase2));
1429 	}
1430 
1431 	/* Save the file using the new passphrase. */
1432 	if ((r = sshkey_save_private(private, identity_file, passphrase1,
1433 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
1434 		error_r(r, "Saving key \"%s\" failed", identity_file);
1435 		freezero(passphrase1, strlen(passphrase1));
1436 		sshkey_free(private);
1437 		free(comment);
1438 		exit(1);
1439 	}
1440 	/* Destroy the passphrase and the copy of the key in memory. */
1441 	freezero(passphrase1, strlen(passphrase1));
1442 	sshkey_free(private);		 /* Destroys contents */
1443 	free(comment);
1444 
1445 	printf("Your identification has been saved with the new passphrase.\n");
1446 	exit(0);
1447 }
1448 
1449 /*
1450  * Print the SSHFP RR.
1451  */
1452 static int
1453 do_print_resource_record(struct passwd *pw, char *fname, char *hname,
1454     int print_generic)
1455 {
1456 	struct sshkey *public;
1457 	char *comment = NULL;
1458 	struct stat st;
1459 	int r;
1460 
1461 	if (fname == NULL)
1462 		fatal_f("no filename");
1463 	if (stat(fname, &st) == -1) {
1464 		if (errno == ENOENT)
1465 			return 0;
1466 		fatal("%s: %s", fname, strerror(errno));
1467 	}
1468 	if ((r = sshkey_load_public(fname, &public, &comment)) != 0)
1469 		fatal_r(r, "Failed to read v2 public key from \"%s\"", fname);
1470 	export_dns_rr(hname, public, stdout, print_generic);
1471 	sshkey_free(public);
1472 	free(comment);
1473 	return 1;
1474 }
1475 
1476 /*
1477  * Change the comment of a private key file.
1478  */
1479 static void
1480 do_change_comment(struct passwd *pw, const char *identity_comment)
1481 {
1482 	char new_comment[1024], *comment, *passphrase;
1483 	struct sshkey *private;
1484 	struct sshkey *public;
1485 	struct stat st;
1486 	int r;
1487 
1488 	if (!have_identity)
1489 		ask_filename(pw, "Enter file in which the key is");
1490 	if (stat(identity_file, &st) == -1)
1491 		fatal("%s: %s", identity_file, strerror(errno));
1492 	if ((r = sshkey_load_private(identity_file, "",
1493 	    &private, &comment)) == 0)
1494 		passphrase = xstrdup("");
1495 	else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
1496 		fatal_r(r, "Cannot load private key \"%s\"", identity_file);
1497 	else {
1498 		if (identity_passphrase)
1499 			passphrase = xstrdup(identity_passphrase);
1500 		else if (identity_new_passphrase)
1501 			passphrase = xstrdup(identity_new_passphrase);
1502 		else
1503 			passphrase = read_passphrase("Enter passphrase: ",
1504 			    RP_ALLOW_STDIN);
1505 		/* Try to load using the passphrase. */
1506 		if ((r = sshkey_load_private(identity_file, passphrase,
1507 		    &private, &comment)) != 0) {
1508 			freezero(passphrase, strlen(passphrase));
1509 			fatal_r(r, "Cannot load private key \"%s\"",
1510 			    identity_file);
1511 		}
1512 	}
1513 
1514 	if (private->type != KEY_ED25519 && private->type != KEY_XMSS &&
1515 	    private_key_format != SSHKEY_PRIVATE_OPENSSH) {
1516 		error("Comments are only supported for keys stored in "
1517 		    "the new format (-o).");
1518 		explicit_bzero(passphrase, strlen(passphrase));
1519 		sshkey_free(private);
1520 		exit(1);
1521 	}
1522 	if (comment)
1523 		printf("Old comment: %s\n", comment);
1524 	else
1525 		printf("No existing comment\n");
1526 
1527 	if (identity_comment) {
1528 		strlcpy(new_comment, identity_comment, sizeof(new_comment));
1529 	} else {
1530 		printf("New comment: ");
1531 		fflush(stdout);
1532 		if (!fgets(new_comment, sizeof(new_comment), stdin)) {
1533 			explicit_bzero(passphrase, strlen(passphrase));
1534 			sshkey_free(private);
1535 			exit(1);
1536 		}
1537 		new_comment[strcspn(new_comment, "\n")] = '\0';
1538 	}
1539 	if (comment != NULL && strcmp(comment, new_comment) == 0) {
1540 		printf("No change to comment\n");
1541 		free(passphrase);
1542 		sshkey_free(private);
1543 		free(comment);
1544 		exit(0);
1545 	}
1546 
1547 	/* Save the file using the new passphrase. */
1548 	if ((r = sshkey_save_private(private, identity_file, passphrase,
1549 	    new_comment, private_key_format, openssh_format_cipher,
1550 	    rounds)) != 0) {
1551 		error_r(r, "Saving key \"%s\" failed", identity_file);
1552 		freezero(passphrase, strlen(passphrase));
1553 		sshkey_free(private);
1554 		free(comment);
1555 		exit(1);
1556 	}
1557 	freezero(passphrase, strlen(passphrase));
1558 	if ((r = sshkey_from_private(private, &public)) != 0)
1559 		fatal_fr(r, "sshkey_from_private");
1560 	sshkey_free(private);
1561 
1562 	strlcat(identity_file, ".pub", sizeof(identity_file));
1563 	if ((r = sshkey_save_public(public, identity_file, new_comment)) != 0)
1564 		fatal_r(r, "Unable to save public key to %s", identity_file);
1565 	sshkey_free(public);
1566 	free(comment);
1567 
1568 	if (strlen(new_comment) > 0)
1569 		printf("Comment '%s' applied\n", new_comment);
1570 	else
1571 		printf("Comment removed\n");
1572 
1573 	exit(0);
1574 }
1575 
1576 static void
1577 cert_ext_add(const char *key, const char *value, int iscrit)
1578 {
1579 	cert_ext = xreallocarray(cert_ext, ncert_ext + 1, sizeof(*cert_ext));
1580 	cert_ext[ncert_ext].key = xstrdup(key);
1581 	cert_ext[ncert_ext].val = value == NULL ? NULL : xstrdup(value);
1582 	cert_ext[ncert_ext].crit = iscrit;
1583 	ncert_ext++;
1584 }
1585 
1586 /* qsort(3) comparison function for certificate extensions */
1587 static int
1588 cert_ext_cmp(const void *_a, const void *_b)
1589 {
1590 	const struct cert_ext *a = (const struct cert_ext *)_a;
1591 	const struct cert_ext *b = (const struct cert_ext *)_b;
1592 	int r;
1593 
1594 	if (a->crit != b->crit)
1595 		return (a->crit < b->crit) ? -1 : 1;
1596 	if ((r = strcmp(a->key, b->key)) != 0)
1597 		return r;
1598 	if ((a->val == NULL) != (b->val == NULL))
1599 		return (a->val == NULL) ? -1 : 1;
1600 	if (a->val != NULL && (r = strcmp(a->val, b->val)) != 0)
1601 		return r;
1602 	return 0;
1603 }
1604 
1605 #define OPTIONS_CRITICAL	1
1606 #define OPTIONS_EXTENSIONS	2
1607 static void
1608 prepare_options_buf(struct sshbuf *c, int which)
1609 {
1610 	struct sshbuf *b;
1611 	size_t i;
1612 	int r;
1613 	const struct cert_ext *ext;
1614 
1615 	if ((b = sshbuf_new()) == NULL)
1616 		fatal_f("sshbuf_new failed");
1617 	sshbuf_reset(c);
1618 	for (i = 0; i < ncert_ext; i++) {
1619 		ext = &cert_ext[i];
1620 		if ((ext->crit && (which & OPTIONS_EXTENSIONS)) ||
1621 		    (!ext->crit && (which & OPTIONS_CRITICAL)))
1622 			continue;
1623 		if (ext->val == NULL) {
1624 			/* flag option */
1625 			debug3_f("%s", ext->key);
1626 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1627 			    (r = sshbuf_put_string(c, NULL, 0)) != 0)
1628 				fatal_fr(r, "prepare flag");
1629 		} else {
1630 			/* key/value option */
1631 			debug3_f("%s=%s", ext->key, ext->val);
1632 			sshbuf_reset(b);
1633 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1634 			    (r = sshbuf_put_cstring(b, ext->val)) != 0 ||
1635 			    (r = sshbuf_put_stringb(c, b)) != 0)
1636 				fatal_fr(r, "prepare k/v");
1637 		}
1638 	}
1639 	sshbuf_free(b);
1640 }
1641 
1642 static void
1643 finalise_cert_exts(void)
1644 {
1645 	/* critical options */
1646 	if (certflags_command != NULL)
1647 		cert_ext_add("force-command", certflags_command, 1);
1648 	if (certflags_src_addr != NULL)
1649 		cert_ext_add("source-address", certflags_src_addr, 1);
1650 	/* extensions */
1651 	if ((certflags_flags & CERTOPT_X_FWD) != 0)
1652 		cert_ext_add("permit-X11-forwarding", NULL, 0);
1653 	if ((certflags_flags & CERTOPT_AGENT_FWD) != 0)
1654 		cert_ext_add("permit-agent-forwarding", NULL, 0);
1655 	if ((certflags_flags & CERTOPT_PORT_FWD) != 0)
1656 		cert_ext_add("permit-port-forwarding", NULL, 0);
1657 	if ((certflags_flags & CERTOPT_PTY) != 0)
1658 		cert_ext_add("permit-pty", NULL, 0);
1659 	if ((certflags_flags & CERTOPT_USER_RC) != 0)
1660 		cert_ext_add("permit-user-rc", NULL, 0);
1661 	if ((certflags_flags & CERTOPT_NO_REQUIRE_USER_PRESENCE) != 0)
1662 		cert_ext_add("no-touch-required", NULL, 0);
1663 	/* order lexically by key */
1664 	if (ncert_ext > 0)
1665 		qsort(cert_ext, ncert_ext, sizeof(*cert_ext), cert_ext_cmp);
1666 }
1667 
1668 static struct sshkey *
1669 load_pkcs11_key(char *path)
1670 {
1671 #ifdef ENABLE_PKCS11
1672 	struct sshkey **keys = NULL, *public, *private = NULL;
1673 	int r, i, nkeys;
1674 
1675 	if ((r = sshkey_load_public(path, &public, NULL)) != 0)
1676 		fatal_r(r, "Couldn't load CA public key \"%s\"", path);
1677 
1678 	nkeys = pkcs11_add_provider(pkcs11provider, identity_passphrase,
1679 	    &keys, NULL);
1680 	debug3_f("%d keys", nkeys);
1681 	if (nkeys <= 0)
1682 		fatal("cannot read public key from pkcs11");
1683 	for (i = 0; i < nkeys; i++) {
1684 		if (sshkey_equal_public(public, keys[i])) {
1685 			private = keys[i];
1686 			continue;
1687 		}
1688 		sshkey_free(keys[i]);
1689 	}
1690 	free(keys);
1691 	sshkey_free(public);
1692 	return private;
1693 #else
1694 	fatal("no pkcs11 support");
1695 #endif /* ENABLE_PKCS11 */
1696 }
1697 
1698 /* Signer for sshkey_certify_custom that uses the agent */
1699 static int
1700 agent_signer(struct sshkey *key, u_char **sigp, size_t *lenp,
1701     const u_char *data, size_t datalen,
1702     const char *alg, const char *provider, const char *pin,
1703     u_int compat, void *ctx)
1704 {
1705 	int *agent_fdp = (int *)ctx;
1706 
1707 	return ssh_agent_sign(*agent_fdp, key, sigp, lenp,
1708 	    data, datalen, alg, compat);
1709 }
1710 
1711 static void
1712 do_ca_sign(struct passwd *pw, const char *ca_key_path, int prefer_agent,
1713     unsigned long long cert_serial, int cert_serial_autoinc,
1714     int argc, char **argv)
1715 {
1716 	int r, i, found, agent_fd = -1;
1717 	u_int n;
1718 	struct sshkey *ca, *public;
1719 	char valid[64], *otmp, *tmp, *cp, *out, *comment;
1720 	char *ca_fp = NULL, **plist = NULL, *pin = NULL;
1721 	struct ssh_identitylist *agent_ids;
1722 	size_t j;
1723 	struct notifier_ctx *notifier = NULL;
1724 
1725 #ifdef ENABLE_PKCS11
1726 	pkcs11_init(1);
1727 #endif
1728 	tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
1729 	if (pkcs11provider != NULL) {
1730 		/* If a PKCS#11 token was specified then try to use it */
1731 		if ((ca = load_pkcs11_key(tmp)) == NULL)
1732 			fatal("No PKCS#11 key matching %s found", ca_key_path);
1733 	} else if (prefer_agent) {
1734 		/*
1735 		 * Agent signature requested. Try to use agent after making
1736 		 * sure the public key specified is actually present in the
1737 		 * agent.
1738 		 */
1739 		if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
1740 			fatal_r(r, "Cannot load CA public key %s", tmp);
1741 		if ((r = ssh_get_authentication_socket(&agent_fd)) != 0)
1742 			fatal_r(r, "Cannot use public key for CA signature");
1743 		if ((r = ssh_fetch_identitylist(agent_fd, &agent_ids)) != 0)
1744 			fatal_r(r, "Retrieve agent key list");
1745 		found = 0;
1746 		for (j = 0; j < agent_ids->nkeys; j++) {
1747 			if (sshkey_equal(ca, agent_ids->keys[j])) {
1748 				found = 1;
1749 				break;
1750 			}
1751 		}
1752 		if (!found)
1753 			fatal("CA key %s not found in agent", tmp);
1754 		ssh_free_identitylist(agent_ids);
1755 		ca->flags |= SSHKEY_FLAG_EXT;
1756 	} else {
1757 		/* CA key is assumed to be a private key on the filesystem */
1758 		ca = load_identity(tmp, NULL);
1759 		if (sshkey_is_sk(ca) &&
1760 		    (ca->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
1761 			if ((pin = read_passphrase("Enter PIN for CA key: ",
1762 			    RP_ALLOW_STDIN)) == NULL)
1763 				fatal_f("couldn't read PIN");
1764 		}
1765 	}
1766 	free(tmp);
1767 
1768 	if (key_type_name != NULL) {
1769 		if (sshkey_type_from_name(key_type_name) != ca->type) {
1770 			fatal("CA key type %s doesn't match specified %s",
1771 			    sshkey_ssh_name(ca), key_type_name);
1772 		}
1773 	} else if (ca->type == KEY_RSA) {
1774 		/* Default to a good signature algorithm */
1775 		key_type_name = "rsa-sha2-512";
1776 	}
1777 	ca_fp = sshkey_fingerprint(ca, fingerprint_hash, SSH_FP_DEFAULT);
1778 
1779 	finalise_cert_exts();
1780 	for (i = 0; i < argc; i++) {
1781 		/* Split list of principals */
1782 		n = 0;
1783 		if (cert_principals != NULL) {
1784 			otmp = tmp = xstrdup(cert_principals);
1785 			plist = NULL;
1786 			for (; (cp = strsep(&tmp, ",")) != NULL; n++) {
1787 				plist = xreallocarray(plist, n + 1, sizeof(*plist));
1788 				if (*(plist[n] = xstrdup(cp)) == '\0')
1789 					fatal("Empty principal name");
1790 			}
1791 			free(otmp);
1792 		}
1793 		if (n > SSHKEY_CERT_MAX_PRINCIPALS)
1794 			fatal("Too many certificate principals specified");
1795 
1796 		tmp = tilde_expand_filename(argv[i], pw->pw_uid);
1797 		if ((r = sshkey_load_public(tmp, &public, &comment)) != 0)
1798 			fatal_r(r, "load pubkey \"%s\"", tmp);
1799 		if (sshkey_is_cert(public))
1800 			fatal_f("key \"%s\" type %s cannot be certified",
1801 			    tmp, sshkey_type(public));
1802 
1803 		/* Prepare certificate to sign */
1804 		if ((r = sshkey_to_certified(public)) != 0)
1805 			fatal_r(r, "Could not upgrade key %s to certificate", tmp);
1806 		public->cert->type = cert_key_type;
1807 		public->cert->serial = (u_int64_t)cert_serial;
1808 		public->cert->key_id = xstrdup(cert_key_id);
1809 		public->cert->nprincipals = n;
1810 		public->cert->principals = plist;
1811 		public->cert->valid_after = cert_valid_from;
1812 		public->cert->valid_before = cert_valid_to;
1813 		prepare_options_buf(public->cert->critical, OPTIONS_CRITICAL);
1814 		prepare_options_buf(public->cert->extensions,
1815 		    OPTIONS_EXTENSIONS);
1816 		if ((r = sshkey_from_private(ca,
1817 		    &public->cert->signature_key)) != 0)
1818 			fatal_r(r, "sshkey_from_private (ca key)");
1819 
1820 		if (agent_fd != -1 && (ca->flags & SSHKEY_FLAG_EXT) != 0) {
1821 			if ((r = sshkey_certify_custom(public, ca,
1822 			    key_type_name, sk_provider, NULL, agent_signer,
1823 			    &agent_fd)) != 0)
1824 				fatal_r(r, "Couldn't certify %s via agent", tmp);
1825 		} else {
1826 			if (sshkey_is_sk(ca) &&
1827 			    (ca->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1828 				notifier = notify_start(0,
1829 				    "Confirm user presence for key %s %s",
1830 				    sshkey_type(ca), ca_fp);
1831 			}
1832 			r = sshkey_certify(public, ca, key_type_name,
1833 			    sk_provider, pin);
1834 			notify_complete(notifier);
1835 			if (r != 0)
1836 				fatal_r(r, "Couldn't certify key %s", tmp);
1837 		}
1838 
1839 		if ((cp = strrchr(tmp, '.')) != NULL && strcmp(cp, ".pub") == 0)
1840 			*cp = '\0';
1841 		xasprintf(&out, "%s-cert.pub", tmp);
1842 		free(tmp);
1843 
1844 		if ((r = sshkey_save_public(public, out, comment)) != 0) {
1845 			fatal_r(r, "Unable to save public key to %s",
1846 			    identity_file);
1847 		}
1848 
1849 		if (!quiet) {
1850 			sshkey_format_cert_validity(public->cert,
1851 			    valid, sizeof(valid));
1852 			logit("Signed %s key %s: id \"%s\" serial %llu%s%s "
1853 			    "valid %s", sshkey_cert_type(public),
1854 			    out, public->cert->key_id,
1855 			    (unsigned long long)public->cert->serial,
1856 			    cert_principals != NULL ? " for " : "",
1857 			    cert_principals != NULL ? cert_principals : "",
1858 			    valid);
1859 		}
1860 
1861 		sshkey_free(public);
1862 		free(out);
1863 		if (cert_serial_autoinc)
1864 			cert_serial++;
1865 	}
1866 	if (pin != NULL)
1867 		freezero(pin, strlen(pin));
1868 	free(ca_fp);
1869 #ifdef ENABLE_PKCS11
1870 	pkcs11_terminate();
1871 #endif
1872 	exit(0);
1873 }
1874 
1875 static u_int64_t
1876 parse_relative_time(const char *s, time_t now)
1877 {
1878 	int64_t mul, secs;
1879 
1880 	mul = *s == '-' ? -1 : 1;
1881 
1882 	if ((secs = convtime(s + 1)) == -1)
1883 		fatal("Invalid relative certificate time %s", s);
1884 	if (mul == -1 && secs > now)
1885 		fatal("Certificate time %s cannot be represented", s);
1886 	return now + (u_int64_t)(secs * mul);
1887 }
1888 
1889 static void
1890 parse_cert_times(char *timespec)
1891 {
1892 	char *from, *to;
1893 	time_t now = time(NULL);
1894 	int64_t secs;
1895 
1896 	/* +timespec relative to now */
1897 	if (*timespec == '+' && strchr(timespec, ':') == NULL) {
1898 		if ((secs = convtime(timespec + 1)) == -1)
1899 			fatal("Invalid relative certificate life %s", timespec);
1900 		cert_valid_to = now + secs;
1901 		/*
1902 		 * Backdate certificate one minute to avoid problems on hosts
1903 		 * with poorly-synchronised clocks.
1904 		 */
1905 		cert_valid_from = ((now - 59)/ 60) * 60;
1906 		return;
1907 	}
1908 
1909 	/*
1910 	 * from:to, where
1911 	 * from := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | "always"
1912 	 *   to := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | "forever"
1913 	 */
1914 	from = xstrdup(timespec);
1915 	to = strchr(from, ':');
1916 	if (to == NULL || from == to || *(to + 1) == '\0')
1917 		fatal("Invalid certificate life specification %s", timespec);
1918 	*to++ = '\0';
1919 
1920 	if (*from == '-' || *from == '+')
1921 		cert_valid_from = parse_relative_time(from, now);
1922 	else if (strcmp(from, "always") == 0)
1923 		cert_valid_from = 0;
1924 	else if (parse_absolute_time(from, &cert_valid_from) != 0)
1925 		fatal("Invalid from time \"%s\"", from);
1926 
1927 	if (*to == '-' || *to == '+')
1928 		cert_valid_to = parse_relative_time(to, now);
1929 	else if (strcmp(to, "forever") == 0)
1930 		cert_valid_to = ~(u_int64_t)0;
1931 	else if (parse_absolute_time(to, &cert_valid_to) != 0)
1932 		fatal("Invalid to time \"%s\"", to);
1933 
1934 	if (cert_valid_to <= cert_valid_from)
1935 		fatal("Empty certificate validity interval");
1936 	free(from);
1937 }
1938 
1939 static void
1940 add_cert_option(char *opt)
1941 {
1942 	char *val, *cp;
1943 	int iscrit = 0;
1944 
1945 	if (strcasecmp(opt, "clear") == 0)
1946 		certflags_flags = 0;
1947 	else if (strcasecmp(opt, "no-x11-forwarding") == 0)
1948 		certflags_flags &= ~CERTOPT_X_FWD;
1949 	else if (strcasecmp(opt, "permit-x11-forwarding") == 0)
1950 		certflags_flags |= CERTOPT_X_FWD;
1951 	else if (strcasecmp(opt, "no-agent-forwarding") == 0)
1952 		certflags_flags &= ~CERTOPT_AGENT_FWD;
1953 	else if (strcasecmp(opt, "permit-agent-forwarding") == 0)
1954 		certflags_flags |= CERTOPT_AGENT_FWD;
1955 	else if (strcasecmp(opt, "no-port-forwarding") == 0)
1956 		certflags_flags &= ~CERTOPT_PORT_FWD;
1957 	else if (strcasecmp(opt, "permit-port-forwarding") == 0)
1958 		certflags_flags |= CERTOPT_PORT_FWD;
1959 	else if (strcasecmp(opt, "no-pty") == 0)
1960 		certflags_flags &= ~CERTOPT_PTY;
1961 	else if (strcasecmp(opt, "permit-pty") == 0)
1962 		certflags_flags |= CERTOPT_PTY;
1963 	else if (strcasecmp(opt, "no-user-rc") == 0)
1964 		certflags_flags &= ~CERTOPT_USER_RC;
1965 	else if (strcasecmp(opt, "permit-user-rc") == 0)
1966 		certflags_flags |= CERTOPT_USER_RC;
1967 	else if (strcasecmp(opt, "touch-required") == 0)
1968 		certflags_flags &= ~CERTOPT_NO_REQUIRE_USER_PRESENCE;
1969 	else if (strcasecmp(opt, "no-touch-required") == 0)
1970 		certflags_flags |= CERTOPT_NO_REQUIRE_USER_PRESENCE;
1971 	else if (strncasecmp(opt, "force-command=", 14) == 0) {
1972 		val = opt + 14;
1973 		if (*val == '\0')
1974 			fatal("Empty force-command option");
1975 		if (certflags_command != NULL)
1976 			fatal("force-command already specified");
1977 		certflags_command = xstrdup(val);
1978 	} else if (strncasecmp(opt, "source-address=", 15) == 0) {
1979 		val = opt + 15;
1980 		if (*val == '\0')
1981 			fatal("Empty source-address option");
1982 		if (certflags_src_addr != NULL)
1983 			fatal("source-address already specified");
1984 		if (addr_match_cidr_list(NULL, val) != 0)
1985 			fatal("Invalid source-address list");
1986 		certflags_src_addr = xstrdup(val);
1987 	} else if (strncasecmp(opt, "extension:", 10) == 0 ||
1988 		   (iscrit = (strncasecmp(opt, "critical:", 9) == 0))) {
1989 		val = xstrdup(strchr(opt, ':') + 1);
1990 		if ((cp = strchr(val, '=')) != NULL)
1991 			*cp++ = '\0';
1992 		cert_ext_add(val, cp, iscrit);
1993 		free(val);
1994 	} else
1995 		fatal("Unsupported certificate option \"%s\"", opt);
1996 }
1997 
1998 static void
1999 show_options(struct sshbuf *optbuf, int in_critical)
2000 {
2001 	char *name, *arg, *hex;
2002 	struct sshbuf *options, *option = NULL;
2003 	int r;
2004 
2005 	if ((options = sshbuf_fromb(optbuf)) == NULL)
2006 		fatal_f("sshbuf_fromb failed");
2007 	while (sshbuf_len(options) != 0) {
2008 		sshbuf_free(option);
2009 		option = NULL;
2010 		if ((r = sshbuf_get_cstring(options, &name, NULL)) != 0 ||
2011 		    (r = sshbuf_froms(options, &option)) != 0)
2012 			fatal_fr(r, "parse option");
2013 		printf("                %s", name);
2014 		if (!in_critical &&
2015 		    (strcmp(name, "permit-X11-forwarding") == 0 ||
2016 		    strcmp(name, "permit-agent-forwarding") == 0 ||
2017 		    strcmp(name, "permit-port-forwarding") == 0 ||
2018 		    strcmp(name, "permit-pty") == 0 ||
2019 		    strcmp(name, "permit-user-rc") == 0 ||
2020 		    strcmp(name, "no-touch-required") == 0)) {
2021 			printf("\n");
2022 		} else if (in_critical &&
2023 		    (strcmp(name, "force-command") == 0 ||
2024 		    strcmp(name, "source-address") == 0)) {
2025 			if ((r = sshbuf_get_cstring(option, &arg, NULL)) != 0)
2026 				fatal_fr(r, "parse critical");
2027 			printf(" %s\n", arg);
2028 			free(arg);
2029 		} else if (sshbuf_len(option) > 0) {
2030 			hex = sshbuf_dtob16(option);
2031 			printf(" UNKNOWN OPTION: %s (len %zu)\n",
2032 			    hex, sshbuf_len(option));
2033 			sshbuf_reset(option);
2034 			free(hex);
2035 		} else
2036 			printf(" UNKNOWN FLAG OPTION\n");
2037 		free(name);
2038 		if (sshbuf_len(option) != 0)
2039 			fatal("Option corrupt: extra data at end");
2040 	}
2041 	sshbuf_free(option);
2042 	sshbuf_free(options);
2043 }
2044 
2045 static void
2046 print_cert(struct sshkey *key)
2047 {
2048 	char valid[64], *key_fp, *ca_fp;
2049 	u_int i;
2050 
2051 	key_fp = sshkey_fingerprint(key, fingerprint_hash, SSH_FP_DEFAULT);
2052 	ca_fp = sshkey_fingerprint(key->cert->signature_key,
2053 	    fingerprint_hash, SSH_FP_DEFAULT);
2054 	if (key_fp == NULL || ca_fp == NULL)
2055 		fatal_f("sshkey_fingerprint fail");
2056 	sshkey_format_cert_validity(key->cert, valid, sizeof(valid));
2057 
2058 	printf("        Type: %s %s certificate\n", sshkey_ssh_name(key),
2059 	    sshkey_cert_type(key));
2060 	printf("        Public key: %s %s\n", sshkey_type(key), key_fp);
2061 	printf("        Signing CA: %s %s (using %s)\n",
2062 	    sshkey_type(key->cert->signature_key), ca_fp,
2063 	    key->cert->signature_type);
2064 	printf("        Key ID: \"%s\"\n", key->cert->key_id);
2065 	printf("        Serial: %llu\n", (unsigned long long)key->cert->serial);
2066 	printf("        Valid: %s\n", valid);
2067 	printf("        Principals: ");
2068 	if (key->cert->nprincipals == 0)
2069 		printf("(none)\n");
2070 	else {
2071 		for (i = 0; i < key->cert->nprincipals; i++)
2072 			printf("\n                %s",
2073 			    key->cert->principals[i]);
2074 		printf("\n");
2075 	}
2076 	printf("        Critical Options: ");
2077 	if (sshbuf_len(key->cert->critical) == 0)
2078 		printf("(none)\n");
2079 	else {
2080 		printf("\n");
2081 		show_options(key->cert->critical, 1);
2082 	}
2083 	printf("        Extensions: ");
2084 	if (sshbuf_len(key->cert->extensions) == 0)
2085 		printf("(none)\n");
2086 	else {
2087 		printf("\n");
2088 		show_options(key->cert->extensions, 0);
2089 	}
2090 }
2091 
2092 static void
2093 do_show_cert(struct passwd *pw)
2094 {
2095 	struct sshkey *key = NULL;
2096 	struct stat st;
2097 	int r, is_stdin = 0, ok = 0;
2098 	FILE *f;
2099 	char *cp, *line = NULL;
2100 	const char *path;
2101 	size_t linesize = 0;
2102 	u_long lnum = 0;
2103 
2104 	if (!have_identity)
2105 		ask_filename(pw, "Enter file in which the key is");
2106 	if (strcmp(identity_file, "-") != 0 && stat(identity_file, &st) == -1)
2107 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
2108 
2109 	path = identity_file;
2110 	if (strcmp(path, "-") == 0) {
2111 		f = stdin;
2112 		path = "(stdin)";
2113 		is_stdin = 1;
2114 	} else if ((f = fopen(identity_file, "r")) == NULL)
2115 		fatal("fopen %s: %s", identity_file, strerror(errno));
2116 
2117 	while (getline(&line, &linesize, f) != -1) {
2118 		lnum++;
2119 		sshkey_free(key);
2120 		key = NULL;
2121 		/* Trim leading space and comments */
2122 		cp = line + strspn(line, " \t");
2123 		if (*cp == '#' || *cp == '\0')
2124 			continue;
2125 		if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2126 			fatal("sshkey_new");
2127 		if ((r = sshkey_read(key, &cp)) != 0) {
2128 			error_r(r, "%s:%lu: invalid key", path, lnum);
2129 			continue;
2130 		}
2131 		if (!sshkey_is_cert(key)) {
2132 			error("%s:%lu is not a certificate", path, lnum);
2133 			continue;
2134 		}
2135 		ok = 1;
2136 		if (!is_stdin && lnum == 1)
2137 			printf("%s:\n", path);
2138 		else
2139 			printf("%s:%lu:\n", path, lnum);
2140 		print_cert(key);
2141 	}
2142 	free(line);
2143 	sshkey_free(key);
2144 	fclose(f);
2145 	exit(ok ? 0 : 1);
2146 }
2147 
2148 static void
2149 load_krl(const char *path, struct ssh_krl **krlp)
2150 {
2151 	struct sshbuf *krlbuf;
2152 	int r;
2153 
2154 	if ((r = sshbuf_load_file(path, &krlbuf)) != 0)
2155 		fatal_r(r, "Unable to load KRL %s", path);
2156 	/* XXX check sigs */
2157 	if ((r = ssh_krl_from_blob(krlbuf, krlp, NULL, 0)) != 0 ||
2158 	    *krlp == NULL)
2159 		fatal_r(r, "Invalid KRL file %s", path);
2160 	sshbuf_free(krlbuf);
2161 }
2162 
2163 static void
2164 hash_to_blob(const char *cp, u_char **blobp, size_t *lenp,
2165     const char *file, u_long lnum)
2166 {
2167 	char *tmp;
2168 	size_t tlen;
2169 	struct sshbuf *b;
2170 	int r;
2171 
2172 	if (strncmp(cp, "SHA256:", 7) != 0)
2173 		fatal("%s:%lu: unsupported hash algorithm", file, lnum);
2174 	cp += 7;
2175 
2176 	/*
2177 	 * OpenSSH base64 hashes omit trailing '='
2178 	 * characters; put them back for decode.
2179 	 */
2180 	tlen = strlen(cp);
2181 	tmp = xmalloc(tlen + 4 + 1);
2182 	strlcpy(tmp, cp, tlen + 1);
2183 	while ((tlen % 4) != 0) {
2184 		tmp[tlen++] = '=';
2185 		tmp[tlen] = '\0';
2186 	}
2187 	if ((b = sshbuf_new()) == NULL)
2188 		fatal_f("sshbuf_new failed");
2189 	if ((r = sshbuf_b64tod(b, tmp)) != 0)
2190 		fatal_r(r, "%s:%lu: decode hash failed", file, lnum);
2191 	free(tmp);
2192 	*lenp = sshbuf_len(b);
2193 	*blobp = xmalloc(*lenp);
2194 	memcpy(*blobp, sshbuf_ptr(b), *lenp);
2195 	sshbuf_free(b);
2196 }
2197 
2198 static void
2199 update_krl_from_file(struct passwd *pw, const char *file, int wild_ca,
2200     const struct sshkey *ca, struct ssh_krl *krl)
2201 {
2202 	struct sshkey *key = NULL;
2203 	u_long lnum = 0;
2204 	char *path, *cp, *ep, *line = NULL;
2205 	u_char *blob = NULL;
2206 	size_t blen = 0, linesize = 0;
2207 	unsigned long long serial, serial2;
2208 	int i, was_explicit_key, was_sha1, was_sha256, was_hash, r;
2209 	FILE *krl_spec;
2210 
2211 	path = tilde_expand_filename(file, pw->pw_uid);
2212 	if (strcmp(path, "-") == 0) {
2213 		krl_spec = stdin;
2214 		free(path);
2215 		path = xstrdup("(standard input)");
2216 	} else if ((krl_spec = fopen(path, "r")) == NULL)
2217 		fatal("fopen %s: %s", path, strerror(errno));
2218 
2219 	if (!quiet)
2220 		printf("Revoking from %s\n", path);
2221 	while (getline(&line, &linesize, krl_spec) != -1) {
2222 		lnum++;
2223 		was_explicit_key = was_sha1 = was_sha256 = was_hash = 0;
2224 		cp = line + strspn(line, " \t");
2225 		/* Trim trailing space, comments and strip \n */
2226 		for (i = 0, r = -1; cp[i] != '\0'; i++) {
2227 			if (cp[i] == '#' || cp[i] == '\n') {
2228 				cp[i] = '\0';
2229 				break;
2230 			}
2231 			if (cp[i] == ' ' || cp[i] == '\t') {
2232 				/* Remember the start of a span of whitespace */
2233 				if (r == -1)
2234 					r = i;
2235 			} else
2236 				r = -1;
2237 		}
2238 		if (r != -1)
2239 			cp[r] = '\0';
2240 		if (*cp == '\0')
2241 			continue;
2242 		if (strncasecmp(cp, "serial:", 7) == 0) {
2243 			if (ca == NULL && !wild_ca) {
2244 				fatal("revoking certificates by serial number "
2245 				    "requires specification of a CA key");
2246 			}
2247 			cp += 7;
2248 			cp = cp + strspn(cp, " \t");
2249 			errno = 0;
2250 			serial = strtoull(cp, &ep, 0);
2251 			if (*cp == '\0' || (*ep != '\0' && *ep != '-'))
2252 				fatal("%s:%lu: invalid serial \"%s\"",
2253 				    path, lnum, cp);
2254 			if (errno == ERANGE && serial == ULLONG_MAX)
2255 				fatal("%s:%lu: serial out of range",
2256 				    path, lnum);
2257 			serial2 = serial;
2258 			if (*ep == '-') {
2259 				cp = ep + 1;
2260 				errno = 0;
2261 				serial2 = strtoull(cp, &ep, 0);
2262 				if (*cp == '\0' || *ep != '\0')
2263 					fatal("%s:%lu: invalid serial \"%s\"",
2264 					    path, lnum, cp);
2265 				if (errno == ERANGE && serial2 == ULLONG_MAX)
2266 					fatal("%s:%lu: serial out of range",
2267 					    path, lnum);
2268 				if (serial2 <= serial)
2269 					fatal("%s:%lu: invalid serial range "
2270 					    "%llu:%llu", path, lnum,
2271 					    (unsigned long long)serial,
2272 					    (unsigned long long)serial2);
2273 			}
2274 			if (ssh_krl_revoke_cert_by_serial_range(krl,
2275 			    ca, serial, serial2) != 0) {
2276 				fatal_f("revoke serial failed");
2277 			}
2278 		} else if (strncasecmp(cp, "id:", 3) == 0) {
2279 			if (ca == NULL && !wild_ca) {
2280 				fatal("revoking certificates by key ID "
2281 				    "requires specification of a CA key");
2282 			}
2283 			cp += 3;
2284 			cp = cp + strspn(cp, " \t");
2285 			if (ssh_krl_revoke_cert_by_key_id(krl, ca, cp) != 0)
2286 				fatal_f("revoke key ID failed");
2287 		} else if (strncasecmp(cp, "hash:", 5) == 0) {
2288 			cp += 5;
2289 			cp = cp + strspn(cp, " \t");
2290 			hash_to_blob(cp, &blob, &blen, file, lnum);
2291 			r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2292 			if (r != 0)
2293 				fatal_fr(r, "revoke key failed");
2294 		} else {
2295 			if (strncasecmp(cp, "key:", 4) == 0) {
2296 				cp += 4;
2297 				cp = cp + strspn(cp, " \t");
2298 				was_explicit_key = 1;
2299 			} else if (strncasecmp(cp, "sha1:", 5) == 0) {
2300 				cp += 5;
2301 				cp = cp + strspn(cp, " \t");
2302 				was_sha1 = 1;
2303 			} else if (strncasecmp(cp, "sha256:", 7) == 0) {
2304 				cp += 7;
2305 				cp = cp + strspn(cp, " \t");
2306 				was_sha256 = 1;
2307 				/*
2308 				 * Just try to process the line as a key.
2309 				 * Parsing will fail if it isn't.
2310 				 */
2311 			}
2312 			if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2313 				fatal("sshkey_new");
2314 			if ((r = sshkey_read(key, &cp)) != 0)
2315 				fatal_r(r, "%s:%lu: invalid key", path, lnum);
2316 			if (was_explicit_key)
2317 				r = ssh_krl_revoke_key_explicit(krl, key);
2318 			else if (was_sha1) {
2319 				if (sshkey_fingerprint_raw(key,
2320 				    SSH_DIGEST_SHA1, &blob, &blen) != 0) {
2321 					fatal("%s:%lu: fingerprint failed",
2322 					    file, lnum);
2323 				}
2324 				r = ssh_krl_revoke_key_sha1(krl, blob, blen);
2325 			} else if (was_sha256) {
2326 				if (sshkey_fingerprint_raw(key,
2327 				    SSH_DIGEST_SHA256, &blob, &blen) != 0) {
2328 					fatal("%s:%lu: fingerprint failed",
2329 					    file, lnum);
2330 				}
2331 				r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2332 			} else
2333 				r = ssh_krl_revoke_key(krl, key);
2334 			if (r != 0)
2335 				fatal_fr(r, "revoke key failed");
2336 			freezero(blob, blen);
2337 			blob = NULL;
2338 			blen = 0;
2339 			sshkey_free(key);
2340 		}
2341 	}
2342 	if (strcmp(path, "-") != 0)
2343 		fclose(krl_spec);
2344 	free(line);
2345 	free(path);
2346 }
2347 
2348 static void
2349 do_gen_krl(struct passwd *pw, int updating, const char *ca_key_path,
2350     unsigned long long krl_version, const char *krl_comment,
2351     int argc, char **argv)
2352 {
2353 	struct ssh_krl *krl;
2354 	struct stat sb;
2355 	struct sshkey *ca = NULL;
2356 	int i, r, wild_ca = 0;
2357 	char *tmp;
2358 	struct sshbuf *kbuf;
2359 
2360 	if (*identity_file == '\0')
2361 		fatal("KRL generation requires an output file");
2362 	if (stat(identity_file, &sb) == -1) {
2363 		if (errno != ENOENT)
2364 			fatal("Cannot access KRL \"%s\": %s",
2365 			    identity_file, strerror(errno));
2366 		if (updating)
2367 			fatal("KRL \"%s\" does not exist", identity_file);
2368 	}
2369 	if (ca_key_path != NULL) {
2370 		if (strcasecmp(ca_key_path, "none") == 0)
2371 			wild_ca = 1;
2372 		else {
2373 			tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
2374 			if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
2375 				fatal_r(r, "Cannot load CA public key %s", tmp);
2376 			free(tmp);
2377 		}
2378 	}
2379 
2380 	if (updating)
2381 		load_krl(identity_file, &krl);
2382 	else if ((krl = ssh_krl_init()) == NULL)
2383 		fatal("couldn't create KRL");
2384 
2385 	if (krl_version != 0)
2386 		ssh_krl_set_version(krl, krl_version);
2387 	if (krl_comment != NULL)
2388 		ssh_krl_set_comment(krl, krl_comment);
2389 
2390 	for (i = 0; i < argc; i++)
2391 		update_krl_from_file(pw, argv[i], wild_ca, ca, krl);
2392 
2393 	if ((kbuf = sshbuf_new()) == NULL)
2394 		fatal("sshbuf_new failed");
2395 	if (ssh_krl_to_blob(krl, kbuf, NULL, 0) != 0)
2396 		fatal("Couldn't generate KRL");
2397 	if ((r = sshbuf_write_file(identity_file, kbuf)) != 0)
2398 		fatal("write %s: %s", identity_file, strerror(errno));
2399 	sshbuf_free(kbuf);
2400 	ssh_krl_free(krl);
2401 	sshkey_free(ca);
2402 }
2403 
2404 static void
2405 do_check_krl(struct passwd *pw, int print_krl, int argc, char **argv)
2406 {
2407 	int i, r, ret = 0;
2408 	char *comment;
2409 	struct ssh_krl *krl;
2410 	struct sshkey *k;
2411 
2412 	if (*identity_file == '\0')
2413 		fatal("KRL checking requires an input file");
2414 	load_krl(identity_file, &krl);
2415 	if (print_krl)
2416 		krl_dump(krl, stdout);
2417 	for (i = 0; i < argc; i++) {
2418 		if ((r = sshkey_load_public(argv[i], &k, &comment)) != 0)
2419 			fatal_r(r, "Cannot load public key %s", argv[i]);
2420 		r = ssh_krl_check_key(krl, k);
2421 		printf("%s%s%s%s: %s\n", argv[i],
2422 		    *comment ? " (" : "", comment, *comment ? ")" : "",
2423 		    r == 0 ? "ok" : "REVOKED");
2424 		if (r != 0)
2425 			ret = 1;
2426 		sshkey_free(k);
2427 		free(comment);
2428 	}
2429 	ssh_krl_free(krl);
2430 	exit(ret);
2431 }
2432 
2433 static struct sshkey *
2434 load_sign_key(const char *keypath, const struct sshkey *pubkey)
2435 {
2436 	size_t i, slen, plen = strlen(keypath);
2437 	char *privpath = xstrdup(keypath);
2438 	const char *suffixes[] = { "-cert.pub", ".pub", NULL };
2439 	struct sshkey *ret = NULL, *privkey = NULL;
2440 	int r;
2441 
2442 	/*
2443 	 * If passed a public key filename, then try to locate the corresponding
2444 	 * private key. This lets us specify certificates on the command-line
2445 	 * and have ssh-keygen find the appropriate private key.
2446 	 */
2447 	for (i = 0; suffixes[i]; i++) {
2448 		slen = strlen(suffixes[i]);
2449 		if (plen <= slen ||
2450 		    strcmp(privpath + plen - slen, suffixes[i]) != 0)
2451 			continue;
2452 		privpath[plen - slen] = '\0';
2453 		debug_f("%s looks like a public key, using private key "
2454 		    "path %s instead", keypath, privpath);
2455 	}
2456 	if ((privkey = load_identity(privpath, NULL)) == NULL) {
2457 		error("Couldn't load identity %s", keypath);
2458 		goto done;
2459 	}
2460 	if (!sshkey_equal_public(pubkey, privkey)) {
2461 		error("Public key %s doesn't match private %s",
2462 		    keypath, privpath);
2463 		goto done;
2464 	}
2465 	if (sshkey_is_cert(pubkey) && !sshkey_is_cert(privkey)) {
2466 		/*
2467 		 * Graft the certificate onto the private key to make
2468 		 * it capable of signing.
2469 		 */
2470 		if ((r = sshkey_to_certified(privkey)) != 0) {
2471 			error_fr(r, "sshkey_to_certified");
2472 			goto done;
2473 		}
2474 		if ((r = sshkey_cert_copy(pubkey, privkey)) != 0) {
2475 			error_fr(r, "sshkey_cert_copy");
2476 			goto done;
2477 		}
2478 	}
2479 	/* success */
2480 	ret = privkey;
2481 	privkey = NULL;
2482  done:
2483 	sshkey_free(privkey);
2484 	free(privpath);
2485 	return ret;
2486 }
2487 
2488 static int
2489 sign_one(struct sshkey *signkey, const char *filename, int fd,
2490     const char *sig_namespace, sshsig_signer *signer, void *signer_ctx)
2491 {
2492 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2493 	int r = SSH_ERR_INTERNAL_ERROR, wfd = -1, oerrno;
2494 	char *wfile = NULL, *asig = NULL, *fp = NULL;
2495 	char *pin = NULL, *prompt = NULL;
2496 
2497 	if (!quiet) {
2498 		if (fd == STDIN_FILENO)
2499 			fprintf(stderr, "Signing data on standard input\n");
2500 		else
2501 			fprintf(stderr, "Signing file %s\n", filename);
2502 	}
2503 	if (signer == NULL && sshkey_is_sk(signkey)) {
2504 		if ((signkey->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
2505 			xasprintf(&prompt, "Enter PIN for %s key: ",
2506 			    sshkey_type(signkey));
2507 			if ((pin = read_passphrase(prompt,
2508 			    RP_ALLOW_STDIN)) == NULL)
2509 				fatal_f("couldn't read PIN");
2510 		}
2511 		if ((signkey->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
2512 			if ((fp = sshkey_fingerprint(signkey, fingerprint_hash,
2513 			    SSH_FP_DEFAULT)) == NULL)
2514 				fatal_f("fingerprint failed");
2515 			fprintf(stderr, "Confirm user presence for key %s %s\n",
2516 			    sshkey_type(signkey), fp);
2517 			free(fp);
2518 		}
2519 	}
2520 	if ((r = sshsig_sign_fd(signkey, NULL, sk_provider, pin,
2521 	    fd, sig_namespace, &sigbuf, signer, signer_ctx)) != 0) {
2522 		error_r(r, "Signing %s failed", filename);
2523 		goto out;
2524 	}
2525 	if ((r = sshsig_armor(sigbuf, &abuf)) != 0) {
2526 		error_fr(r, "sshsig_armor");
2527 		goto out;
2528 	}
2529 	if ((asig = sshbuf_dup_string(abuf)) == NULL) {
2530 		error_f("buffer error");
2531 		r = SSH_ERR_ALLOC_FAIL;
2532 		goto out;
2533 	}
2534 
2535 	if (fd == STDIN_FILENO) {
2536 		fputs(asig, stdout);
2537 		fflush(stdout);
2538 	} else {
2539 		xasprintf(&wfile, "%s.sig", filename);
2540 		if (confirm_overwrite(wfile)) {
2541 			if ((wfd = open(wfile, O_WRONLY|O_CREAT|O_TRUNC,
2542 			    0666)) == -1) {
2543 				oerrno = errno;
2544 				error("Cannot open %s: %s",
2545 				    wfile, strerror(errno));
2546 				errno = oerrno;
2547 				r = SSH_ERR_SYSTEM_ERROR;
2548 				goto out;
2549 			}
2550 			if (atomicio(vwrite, wfd, asig,
2551 			    strlen(asig)) != strlen(asig)) {
2552 				oerrno = errno;
2553 				error("Cannot write to %s: %s",
2554 				    wfile, strerror(errno));
2555 				errno = oerrno;
2556 				r = SSH_ERR_SYSTEM_ERROR;
2557 				goto out;
2558 			}
2559 			if (!quiet) {
2560 				fprintf(stderr, "Write signature to %s\n",
2561 				    wfile);
2562 			}
2563 		}
2564 	}
2565 	/* success */
2566 	r = 0;
2567  out:
2568 	free(wfile);
2569 	free(prompt);
2570 	free(asig);
2571 	if (pin != NULL)
2572 		freezero(pin, strlen(pin));
2573 	sshbuf_free(abuf);
2574 	sshbuf_free(sigbuf);
2575 	if (wfd != -1)
2576 		close(wfd);
2577 	return r;
2578 }
2579 
2580 static int
2581 sig_sign(const char *keypath, const char *sig_namespace, int argc, char **argv)
2582 {
2583 	int i, fd = -1, r, ret = -1;
2584 	int agent_fd = -1;
2585 	struct sshkey *pubkey = NULL, *privkey = NULL, *signkey = NULL;
2586 	sshsig_signer *signer = NULL;
2587 
2588 	/* Check file arguments. */
2589 	for (i = 0; i < argc; i++) {
2590 		if (strcmp(argv[i], "-") != 0)
2591 			continue;
2592 		if (i > 0 || argc > 1)
2593 			fatal("Cannot sign mix of paths and standard input");
2594 	}
2595 
2596 	if ((r = sshkey_load_public(keypath, &pubkey, NULL)) != 0) {
2597 		error_r(r, "Couldn't load public key %s", keypath);
2598 		goto done;
2599 	}
2600 
2601 	if ((r = ssh_get_authentication_socket(&agent_fd)) != 0)
2602 		debug_r(r, "Couldn't get agent socket");
2603 	else {
2604 		if ((r = ssh_agent_has_key(agent_fd, pubkey)) == 0)
2605 			signer = agent_signer;
2606 		else
2607 			debug_r(r, "Couldn't find key in agent");
2608 	}
2609 
2610 	if (signer == NULL) {
2611 		/* Not using agent - try to load private key */
2612 		if ((privkey = load_sign_key(keypath, pubkey)) == NULL)
2613 			goto done;
2614 		signkey = privkey;
2615 	} else {
2616 		/* Will use key in agent */
2617 		signkey = pubkey;
2618 	}
2619 
2620 	if (argc == 0) {
2621 		if ((r = sign_one(signkey, "(stdin)", STDIN_FILENO,
2622 		    sig_namespace, signer, &agent_fd)) != 0)
2623 			goto done;
2624 	} else {
2625 		for (i = 0; i < argc; i++) {
2626 			if (strcmp(argv[i], "-") == 0)
2627 				fd = STDIN_FILENO;
2628 			else if ((fd = open(argv[i], O_RDONLY)) == -1) {
2629 				error("Cannot open %s for signing: %s",
2630 				    argv[i], strerror(errno));
2631 				goto done;
2632 			}
2633 			if ((r = sign_one(signkey, argv[i], fd, sig_namespace,
2634 			    signer, &agent_fd)) != 0)
2635 				goto done;
2636 			if (fd != STDIN_FILENO)
2637 				close(fd);
2638 			fd = -1;
2639 		}
2640 	}
2641 
2642 	ret = 0;
2643 done:
2644 	if (fd != -1 && fd != STDIN_FILENO)
2645 		close(fd);
2646 	sshkey_free(pubkey);
2647 	sshkey_free(privkey);
2648 	return ret;
2649 }
2650 
2651 static int
2652 sig_verify(const char *signature, const char *sig_namespace,
2653     const char *principal, const char *allowed_keys, const char *revoked_keys)
2654 {
2655 	int r, ret = -1;
2656 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2657 	struct sshkey *sign_key = NULL;
2658 	char *fp = NULL;
2659 	struct sshkey_sig_details *sig_details = NULL;
2660 
2661 	memset(&sig_details, 0, sizeof(sig_details));
2662 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2663 		error_r(r, "Couldn't read signature file");
2664 		goto done;
2665 	}
2666 
2667 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2668 		error_fr(r, "sshsig_armor");
2669 		goto done;
2670 	}
2671 	if ((r = sshsig_verify_fd(sigbuf, STDIN_FILENO, sig_namespace,
2672 	    &sign_key, &sig_details)) != 0)
2673 		goto done; /* sshsig_verify() prints error */
2674 
2675 	if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2676 	    SSH_FP_DEFAULT)) == NULL)
2677 		fatal_f("sshkey_fingerprint failed");
2678 	debug("Valid (unverified) signature from key %s", fp);
2679 	if (sig_details != NULL) {
2680 		debug2_f("signature details: counter = %u, flags = 0x%02x",
2681 		    sig_details->sk_counter, sig_details->sk_flags);
2682 	}
2683 	free(fp);
2684 	fp = NULL;
2685 
2686 	if (revoked_keys != NULL) {
2687 		if ((r = sshkey_check_revoked(sign_key, revoked_keys)) != 0) {
2688 			debug3_fr(r, "sshkey_check_revoked");
2689 			goto done;
2690 		}
2691 	}
2692 
2693 	if (allowed_keys != NULL && (r = sshsig_check_allowed_keys(allowed_keys,
2694 	    sign_key, principal, sig_namespace)) != 0) {
2695 		debug3_fr(r, "sshsig_check_allowed_keys");
2696 		goto done;
2697 	}
2698 	/* success */
2699 	ret = 0;
2700 done:
2701 	if (!quiet) {
2702 		if (ret == 0) {
2703 			if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2704 			    SSH_FP_DEFAULT)) == NULL)
2705 				fatal_f("sshkey_fingerprint failed");
2706 			if (principal == NULL) {
2707 				printf("Good \"%s\" signature with %s key %s\n",
2708 				       sig_namespace, sshkey_type(sign_key), fp);
2709 
2710 			} else {
2711 				printf("Good \"%s\" signature for %s with %s key %s\n",
2712 				       sig_namespace, principal,
2713 				       sshkey_type(sign_key), fp);
2714 			}
2715 		} else {
2716 			printf("Could not verify signature.\n");
2717 		}
2718 	}
2719 	sshbuf_free(sigbuf);
2720 	sshbuf_free(abuf);
2721 	sshkey_free(sign_key);
2722 	sshkey_sig_details_free(sig_details);
2723 	free(fp);
2724 	return ret;
2725 }
2726 
2727 static int
2728 sig_find_principals(const char *signature, const char *allowed_keys) {
2729 	int r, ret = -1;
2730 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2731 	struct sshkey *sign_key = NULL;
2732 	char *principals = NULL, *cp, *tmp;
2733 
2734 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2735 		error_r(r, "Couldn't read signature file");
2736 		goto done;
2737 	}
2738 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2739 		error_fr(r, "sshsig_armor");
2740 		goto done;
2741 	}
2742 	if ((r = sshsig_get_pubkey(sigbuf, &sign_key)) != 0) {
2743 		error_fr(r, "sshsig_get_pubkey");
2744 		goto done;
2745 	}
2746 	if ((r = sshsig_find_principals(allowed_keys, sign_key,
2747 	    &principals)) != 0) {
2748 		error_fr(r, "sshsig_get_principal");
2749 		goto done;
2750 	}
2751 	ret = 0;
2752 done:
2753 	if (ret == 0 ) {
2754 		/* Emit matching principals one per line */
2755 		tmp = principals;
2756 		while ((cp = strsep(&tmp, ",")) != NULL && *cp != '\0')
2757 			puts(cp);
2758 	} else {
2759 		fprintf(stderr, "No principal matched.\n");
2760 	}
2761 	sshbuf_free(sigbuf);
2762 	sshbuf_free(abuf);
2763 	sshkey_free(sign_key);
2764 	free(principals);
2765 	return ret;
2766 }
2767 
2768 static void
2769 do_moduli_gen(const char *out_file, char **opts, size_t nopts)
2770 {
2771 #ifdef WITH_OPENSSL
2772 	/* Moduli generation/screening */
2773 	u_int32_t memory = 0;
2774 	BIGNUM *start = NULL;
2775 	int moduli_bits = 0;
2776 	FILE *out;
2777 	size_t i;
2778 	const char *errstr;
2779 
2780 	/* Parse options */
2781 	for (i = 0; i < nopts; i++) {
2782 		if (strncmp(opts[i], "memory=", 7) == 0) {
2783 			memory = (u_int32_t)strtonum(opts[i]+7, 1,
2784 			    UINT_MAX, &errstr);
2785 			if (errstr) {
2786 				fatal("Memory limit is %s: %s",
2787 				    errstr, opts[i]+7);
2788 			}
2789 		} else if (strncmp(opts[i], "start=", 6) == 0) {
2790 			/* XXX - also compare length against bits */
2791 			if (BN_hex2bn(&start, opts[i]+6) == 0)
2792 				fatal("Invalid start point.");
2793 		} else if (strncmp(opts[i], "bits=", 5) == 0) {
2794 			moduli_bits = (int)strtonum(opts[i]+5, 1,
2795 			    INT_MAX, &errstr);
2796 			if (errstr) {
2797 				fatal("Invalid number: %s (%s)",
2798 					opts[i]+12, errstr);
2799 			}
2800 		} else {
2801 			fatal("Option \"%s\" is unsupported for moduli "
2802 			    "generation", opts[i]);
2803 		}
2804 	}
2805 
2806 	if ((out = fopen(out_file, "w")) == NULL) {
2807 		fatal("Couldn't open modulus candidate file \"%s\": %s",
2808 		    out_file, strerror(errno));
2809 	}
2810 	setvbuf(out, NULL, _IOLBF, 0);
2811 
2812 	if (moduli_bits == 0)
2813 		moduli_bits = DEFAULT_BITS;
2814 	if (gen_candidates(out, memory, moduli_bits, start) != 0)
2815 		fatal("modulus candidate generation failed");
2816 #else /* WITH_OPENSSL */
2817 	fatal("Moduli generation is not supported");
2818 #endif /* WITH_OPENSSL */
2819 }
2820 
2821 static void
2822 do_moduli_screen(const char *out_file, char **opts, size_t nopts)
2823 {
2824 #ifdef WITH_OPENSSL
2825 	/* Moduli generation/screening */
2826 	char *checkpoint = NULL;
2827 	u_int32_t generator_wanted = 0;
2828 	unsigned long start_lineno = 0, lines_to_process = 0;
2829 	int prime_tests = 0;
2830 	FILE *out, *in = stdin;
2831 	size_t i;
2832 	const char *errstr;
2833 
2834 	/* Parse options */
2835 	for (i = 0; i < nopts; i++) {
2836 		if (strncmp(opts[i], "lines=", 6) == 0) {
2837 			lines_to_process = strtoul(opts[i]+6, NULL, 10);
2838 		} else if (strncmp(opts[i], "start-line=", 11) == 0) {
2839 			start_lineno = strtoul(opts[i]+11, NULL, 10);
2840 		} else if (strncmp(opts[i], "checkpoint=", 11) == 0) {
2841 			checkpoint = xstrdup(opts[i]+11);
2842 		} else if (strncmp(opts[i], "generator=", 10) == 0) {
2843 			generator_wanted = (u_int32_t)strtonum(
2844 			    opts[i]+10, 1, UINT_MAX, &errstr);
2845 			if (errstr != NULL) {
2846 				fatal("Generator invalid: %s (%s)",
2847 				    opts[i]+10, errstr);
2848 			}
2849 		} else if (strncmp(opts[i], "prime-tests=", 12) == 0) {
2850 			prime_tests = (int)strtonum(opts[i]+12, 1,
2851 			    INT_MAX, &errstr);
2852 			if (errstr) {
2853 				fatal("Invalid number: %s (%s)",
2854 					opts[i]+12, errstr);
2855 			}
2856 		} else {
2857 			fatal("Option \"%s\" is unsupported for moduli "
2858 			    "screening", opts[i]);
2859 		}
2860 	}
2861 
2862 	if (have_identity && strcmp(identity_file, "-") != 0) {
2863 		if ((in = fopen(identity_file, "r")) == NULL) {
2864 			fatal("Couldn't open modulus candidate "
2865 			    "file \"%s\": %s", identity_file,
2866 			    strerror(errno));
2867 		}
2868 	}
2869 
2870 	if ((out = fopen(out_file, "a")) == NULL) {
2871 		fatal("Couldn't open moduli file \"%s\": %s",
2872 		    out_file, strerror(errno));
2873 	}
2874 	setvbuf(out, NULL, _IOLBF, 0);
2875 	if (prime_test(in, out, prime_tests == 0 ? 100 : prime_tests,
2876 	    generator_wanted, checkpoint,
2877 	    start_lineno, lines_to_process) != 0)
2878 		fatal("modulus screening failed");
2879 #else /* WITH_OPENSSL */
2880 	fatal("Moduli screening is not supported");
2881 #endif /* WITH_OPENSSL */
2882 }
2883 
2884 static char *
2885 private_key_passphrase(void)
2886 {
2887 	char *passphrase1, *passphrase2;
2888 
2889 	/* Ask for a passphrase (twice). */
2890 	if (identity_passphrase)
2891 		passphrase1 = xstrdup(identity_passphrase);
2892 	else if (identity_new_passphrase)
2893 		passphrase1 = xstrdup(identity_new_passphrase);
2894 	else {
2895 passphrase_again:
2896 		passphrase1 =
2897 			read_passphrase("Enter passphrase (empty for no "
2898 			    "passphrase): ", RP_ALLOW_STDIN);
2899 		passphrase2 = read_passphrase("Enter same passphrase again: ",
2900 		    RP_ALLOW_STDIN);
2901 		if (strcmp(passphrase1, passphrase2) != 0) {
2902 			/*
2903 			 * The passphrases do not match.  Clear them and
2904 			 * retry.
2905 			 */
2906 			freezero(passphrase1, strlen(passphrase1));
2907 			freezero(passphrase2, strlen(passphrase2));
2908 			printf("Passphrases do not match.  Try again.\n");
2909 			goto passphrase_again;
2910 		}
2911 		/* Clear the other copy of the passphrase. */
2912 		freezero(passphrase2, strlen(passphrase2));
2913 	}
2914 	return passphrase1;
2915 }
2916 
2917 static const char *
2918 skip_ssh_url_preamble(const char *s)
2919 {
2920 	if (strncmp(s, "ssh://", 6) == 0)
2921 		return s + 6;
2922 	else if (strncmp(s, "ssh:", 4) == 0)
2923 		return s + 4;
2924 	return s;
2925 }
2926 
2927 static int
2928 do_download_sk(const char *skprovider, const char *device)
2929 {
2930 	struct sshkey **keys;
2931 	size_t nkeys, i;
2932 	int r, ret = -1;
2933 	char *fp, *pin = NULL, *pass = NULL, *path, *pubpath;
2934 	const char *ext;
2935 
2936 	if (skprovider == NULL)
2937 		fatal("Cannot download keys without provider");
2938 
2939 	pin = read_passphrase("Enter PIN for authenticator: ", RP_ALLOW_STDIN);
2940 	if (!quiet) {
2941 		printf("You may need to touch your authenticator "
2942 		    "to authorize key download.\n");
2943 	}
2944 	if ((r = sshsk_load_resident(skprovider, device, pin,
2945 	    &keys, &nkeys)) != 0) {
2946 		if (pin != NULL)
2947 			freezero(pin, strlen(pin));
2948 		error_r(r, "Unable to load resident keys");
2949 		return -1;
2950 	}
2951 	if (nkeys == 0)
2952 		logit("No keys to download");
2953 	if (pin != NULL)
2954 		freezero(pin, strlen(pin));
2955 
2956 	for (i = 0; i < nkeys; i++) {
2957 		if (keys[i]->type != KEY_ECDSA_SK &&
2958 		    keys[i]->type != KEY_ED25519_SK) {
2959 			error("Unsupported key type %s (%d)",
2960 			    sshkey_type(keys[i]), keys[i]->type);
2961 			continue;
2962 		}
2963 		if ((fp = sshkey_fingerprint(keys[i],
2964 		    fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
2965 			fatal_f("sshkey_fingerprint failed");
2966 		debug_f("key %zu: %s %s %s (flags 0x%02x)", i,
2967 		    sshkey_type(keys[i]), fp, keys[i]->sk_application,
2968 		    keys[i]->sk_flags);
2969 		ext = skip_ssh_url_preamble(keys[i]->sk_application);
2970 		xasprintf(&path, "id_%s_rk%s%s",
2971 		    keys[i]->type == KEY_ECDSA_SK ? "ecdsa_sk" : "ed25519_sk",
2972 		    *ext == '\0' ? "" : "_", ext);
2973 
2974 		/* If the file already exists, ask the user to confirm. */
2975 		if (!confirm_overwrite(path)) {
2976 			free(path);
2977 			break;
2978 		}
2979 
2980 		/* Save the key with the application string as the comment */
2981 		if (pass == NULL)
2982 			pass = private_key_passphrase();
2983 		if ((r = sshkey_save_private(keys[i], path, pass,
2984 		    keys[i]->sk_application, private_key_format,
2985 		    openssh_format_cipher, rounds)) != 0) {
2986 			error_r(r, "Saving key \"%s\" failed", path);
2987 			free(path);
2988 			break;
2989 		}
2990 		if (!quiet) {
2991 			printf("Saved %s key%s%s to %s\n",
2992 			    sshkey_type(keys[i]),
2993 			    *ext != '\0' ? " " : "",
2994 			    *ext != '\0' ? keys[i]->sk_application : "",
2995 			    path);
2996 		}
2997 
2998 		/* Save public key too */
2999 		xasprintf(&pubpath, "%s.pub", path);
3000 		free(path);
3001 		if ((r = sshkey_save_public(keys[i], pubpath,
3002 		    keys[i]->sk_application)) != 0) {
3003 			error_r(r, "Saving public key \"%s\" failed", pubpath);
3004 			free(pubpath);
3005 			break;
3006 		}
3007 		free(pubpath);
3008 	}
3009 
3010 	if (i >= nkeys)
3011 		ret = 0; /* success */
3012 	if (pass != NULL)
3013 		freezero(pass, strlen(pass));
3014 	for (i = 0; i < nkeys; i++)
3015 		sshkey_free(keys[i]);
3016 	free(keys);
3017 	return ret;
3018 }
3019 
3020 static void
3021 save_attestation(struct sshbuf *attest, const char *path)
3022 {
3023 	mode_t omask;
3024 	int r;
3025 
3026 	if (path == NULL)
3027 		return; /* nothing to do */
3028 	if (attest == NULL || sshbuf_len(attest) == 0)
3029 		fatal("Enrollment did not return attestation data");
3030 	omask = umask(077);
3031 	r = sshbuf_write_file(path, attest);
3032 	umask(omask);
3033 	if (r != 0)
3034 		fatal_r(r, "Unable to write attestation data \"%s\"", path);
3035 	if (!quiet)
3036 		printf("Your FIDO attestation certificate has been saved in "
3037 		    "%s\n", path);
3038 }
3039 
3040 static void
3041 usage(void)
3042 {
3043 	fprintf(stderr,
3044 	    "usage: ssh-keygen [-q] [-a rounds] [-b bits] [-C comment] [-f output_keyfile]\n"
3045 	    "                  [-m format] [-N new_passphrase] [-O option]\n"
3046 	    "                  [-t dsa | ecdsa | ecdsa-sk | ed25519 | ed25519-sk | rsa]\n"
3047 	    "                  [-w provider]\n"
3048 	    "       ssh-keygen -p [-a rounds] [-f keyfile] [-m format] [-N new_passphrase]\n"
3049 	    "                   [-P old_passphrase]\n"
3050 	    "       ssh-keygen -i [-f input_keyfile] [-m key_format]\n"
3051 	    "       ssh-keygen -e [-f input_keyfile] [-m key_format]\n"
3052 	    "       ssh-keygen -y [-f input_keyfile]\n"
3053 	    "       ssh-keygen -c [-a rounds] [-C comment] [-f keyfile] [-P passphrase]\n"
3054 	    "       ssh-keygen -l [-v] [-E fingerprint_hash] [-f input_keyfile]\n"
3055 	    "       ssh-keygen -B [-f input_keyfile]\n");
3056 #ifdef ENABLE_PKCS11
3057 	fprintf(stderr,
3058 	    "       ssh-keygen -D pkcs11\n");
3059 #endif
3060 	fprintf(stderr,
3061 	    "       ssh-keygen -F hostname [-lv] [-f known_hosts_file]\n"
3062 	    "       ssh-keygen -H [-f known_hosts_file]\n"
3063 	    "       ssh-keygen -K [-a rounds] [-w provider]\n"
3064 	    "       ssh-keygen -R hostname [-f known_hosts_file]\n"
3065 	    "       ssh-keygen -r hostname [-g] [-f input_keyfile]\n"
3066 #ifdef WITH_OPENSSL
3067 	    "       ssh-keygen -M generate [-O option] output_file\n"
3068 	    "       ssh-keygen -M screen [-f input_file] [-O option] output_file\n"
3069 #endif
3070 	    "       ssh-keygen -I certificate_identity -s ca_key [-hU] [-D pkcs11_provider]\n"
3071 	    "                  [-n principals] [-O option] [-V validity_interval]\n"
3072 	    "                  [-z serial_number] file ...\n"
3073 	    "       ssh-keygen -L [-f input_keyfile]\n"
3074 	    "       ssh-keygen -A [-a rounds] [-f prefix_path]\n"
3075 	    "       ssh-keygen -k -f krl_file [-u] [-s ca_public] [-z version_number]\n"
3076 	    "                  file ...\n"
3077 	    "       ssh-keygen -Q [-l] -f krl_file [file ...]\n"
3078 	    "       ssh-keygen -Y find-principals -s signature_file -f allowed_signers_file\n"
3079 	    "       ssh-keygen -Y check-novalidate -n namespace -s signature_file\n"
3080 	    "       ssh-keygen -Y sign -f key_file -n namespace file ...\n"
3081 	    "       ssh-keygen -Y verify -f allowed_signers_file -I signer_identity\n"
3082 	    "       		-n namespace -s signature_file [-r revocation_file]\n");
3083 	exit(1);
3084 }
3085 
3086 /*
3087  * Main program for key management.
3088  */
3089 int
3090 main(int argc, char **argv)
3091 {
3092 	char comment[1024], *passphrase;
3093 	char *rr_hostname = NULL, *ep, *fp, *ra;
3094 	struct sshkey *private, *public;
3095 	struct passwd *pw;
3096 	int r, opt, type;
3097 	int change_passphrase = 0, change_comment = 0, show_cert = 0;
3098 	int find_host = 0, delete_host = 0, hash_hosts = 0;
3099 	int gen_all_hostkeys = 0, gen_krl = 0, update_krl = 0, check_krl = 0;
3100 	int prefer_agent = 0, convert_to = 0, convert_from = 0;
3101 	int print_public = 0, print_generic = 0, cert_serial_autoinc = 0;
3102 	int do_gen_candidates = 0, do_screen_candidates = 0, download_sk = 0;
3103 	unsigned long long cert_serial = 0;
3104 	char *identity_comment = NULL, *ca_key_path = NULL, **opts = NULL;
3105 	char *sk_application = NULL, *sk_device = NULL, *sk_user = NULL;
3106 	char *sk_attestation_path = NULL;
3107 	struct sshbuf *challenge = NULL, *attest = NULL;
3108 	size_t i, nopts = 0;
3109 	u_int32_t bits = 0;
3110 	uint8_t sk_flags = SSH_SK_USER_PRESENCE_REQD;
3111 	const char *errstr;
3112 	int log_level = SYSLOG_LEVEL_INFO;
3113 	char *sign_op = NULL;
3114 
3115 	extern int optind;
3116 	extern char *optarg;
3117 
3118 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
3119 	sanitise_stdfd();
3120 
3121 #ifdef WITH_OPENSSL
3122 	OpenSSL_add_all_algorithms();
3123 #endif
3124 	log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
3125 
3126 	setlocale(LC_CTYPE, "");
3127 
3128 	/* we need this for the home * directory.  */
3129 	pw = getpwuid(getuid());
3130 	if (!pw)
3131 		fatal("No user exists for uid %lu", (u_long)getuid());
3132 	if (gethostname(hostname, sizeof(hostname)) == -1)
3133 		fatal("gethostname: %s", strerror(errno));
3134 
3135 	sk_provider = getenv("SSH_SK_PROVIDER");
3136 
3137 	/* Remaining characters: dGjJSTWx */
3138 	while ((opt = getopt(argc, argv, "ABHKLQUXceghiklopquvy"
3139 	    "C:D:E:F:I:M:N:O:P:R:V:Y:Z:"
3140 	    "a:b:f:g:m:n:r:s:t:w:z:")) != -1) {
3141 		switch (opt) {
3142 		case 'A':
3143 			gen_all_hostkeys = 1;
3144 			break;
3145 		case 'b':
3146 			bits = (u_int32_t)strtonum(optarg, 1, UINT32_MAX,
3147 			    &errstr);
3148 			if (errstr)
3149 				fatal("Bits has bad value %s (%s)",
3150 					optarg, errstr);
3151 			break;
3152 		case 'E':
3153 			fingerprint_hash = ssh_digest_alg_by_name(optarg);
3154 			if (fingerprint_hash == -1)
3155 				fatal("Invalid hash algorithm \"%s\"", optarg);
3156 			break;
3157 		case 'F':
3158 			find_host = 1;
3159 			rr_hostname = optarg;
3160 			break;
3161 		case 'H':
3162 			hash_hosts = 1;
3163 			break;
3164 		case 'I':
3165 			cert_key_id = optarg;
3166 			break;
3167 		case 'R':
3168 			delete_host = 1;
3169 			rr_hostname = optarg;
3170 			break;
3171 		case 'L':
3172 			show_cert = 1;
3173 			break;
3174 		case 'l':
3175 			print_fingerprint = 1;
3176 			break;
3177 		case 'B':
3178 			print_bubblebabble = 1;
3179 			break;
3180 		case 'm':
3181 			if (strcasecmp(optarg, "RFC4716") == 0 ||
3182 			    strcasecmp(optarg, "ssh2") == 0) {
3183 				convert_format = FMT_RFC4716;
3184 				break;
3185 			}
3186 			if (strcasecmp(optarg, "PKCS8") == 0) {
3187 				convert_format = FMT_PKCS8;
3188 				private_key_format = SSHKEY_PRIVATE_PKCS8;
3189 				break;
3190 			}
3191 			if (strcasecmp(optarg, "PEM") == 0) {
3192 				convert_format = FMT_PEM;
3193 				private_key_format = SSHKEY_PRIVATE_PEM;
3194 				break;
3195 			}
3196 			fatal("Unsupported conversion format \"%s\"", optarg);
3197 		case 'n':
3198 			cert_principals = optarg;
3199 			break;
3200 		case 'o':
3201 			/* no-op; new format is already the default */
3202 			break;
3203 		case 'p':
3204 			change_passphrase = 1;
3205 			break;
3206 		case 'c':
3207 			change_comment = 1;
3208 			break;
3209 		case 'f':
3210 			if (strlcpy(identity_file, optarg,
3211 			    sizeof(identity_file)) >= sizeof(identity_file))
3212 				fatal("Identity filename too long");
3213 			have_identity = 1;
3214 			break;
3215 		case 'g':
3216 			print_generic = 1;
3217 			break;
3218 		case 'K':
3219 			download_sk = 1;
3220 			break;
3221 		case 'P':
3222 			identity_passphrase = optarg;
3223 			break;
3224 		case 'N':
3225 			identity_new_passphrase = optarg;
3226 			break;
3227 		case 'Q':
3228 			check_krl = 1;
3229 			break;
3230 		case 'O':
3231 			opts = xrecallocarray(opts, nopts, nopts + 1,
3232 			    sizeof(*opts));
3233 			opts[nopts++] = xstrdup(optarg);
3234 			break;
3235 		case 'Z':
3236 			openssh_format_cipher = optarg;
3237 			break;
3238 		case 'C':
3239 			identity_comment = optarg;
3240 			break;
3241 		case 'q':
3242 			quiet = 1;
3243 			break;
3244 		case 'e':
3245 			/* export key */
3246 			convert_to = 1;
3247 			break;
3248 		case 'h':
3249 			cert_key_type = SSH2_CERT_TYPE_HOST;
3250 			certflags_flags = 0;
3251 			break;
3252 		case 'k':
3253 			gen_krl = 1;
3254 			break;
3255 		case 'i':
3256 		case 'X':
3257 			/* import key */
3258 			convert_from = 1;
3259 			break;
3260 		case 'y':
3261 			print_public = 1;
3262 			break;
3263 		case 's':
3264 			ca_key_path = optarg;
3265 			break;
3266 		case 't':
3267 			key_type_name = optarg;
3268 			break;
3269 		case 'D':
3270 			pkcs11provider = optarg;
3271 			break;
3272 		case 'U':
3273 			prefer_agent = 1;
3274 			break;
3275 		case 'u':
3276 			update_krl = 1;
3277 			break;
3278 		case 'v':
3279 			if (log_level == SYSLOG_LEVEL_INFO)
3280 				log_level = SYSLOG_LEVEL_DEBUG1;
3281 			else {
3282 				if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
3283 				    log_level < SYSLOG_LEVEL_DEBUG3)
3284 					log_level++;
3285 			}
3286 			break;
3287 		case 'r':
3288 			rr_hostname = optarg;
3289 			break;
3290 		case 'a':
3291 			rounds = (int)strtonum(optarg, 1, INT_MAX, &errstr);
3292 			if (errstr)
3293 				fatal("Invalid number: %s (%s)",
3294 					optarg, errstr);
3295 			break;
3296 		case 'V':
3297 			parse_cert_times(optarg);
3298 			break;
3299 		case 'Y':
3300 			sign_op = optarg;
3301 			break;
3302 		case 'w':
3303 			sk_provider = optarg;
3304 			break;
3305 		case 'z':
3306 			errno = 0;
3307 			if (*optarg == '+') {
3308 				cert_serial_autoinc = 1;
3309 				optarg++;
3310 			}
3311 			cert_serial = strtoull(optarg, &ep, 10);
3312 			if (*optarg < '0' || *optarg > '9' || *ep != '\0' ||
3313 			    (errno == ERANGE && cert_serial == ULLONG_MAX))
3314 				fatal("Invalid serial number \"%s\"", optarg);
3315 			break;
3316 		case 'M':
3317 			if (strcmp(optarg, "generate") == 0)
3318 				do_gen_candidates = 1;
3319 			else if (strcmp(optarg, "screen") == 0)
3320 				do_screen_candidates = 1;
3321 			else
3322 				fatal("Unsupported moduli option %s", optarg);
3323 			break;
3324 		case '?':
3325 		default:
3326 			usage();
3327 		}
3328 	}
3329 
3330 	if (sk_provider == NULL)
3331 		sk_provider = "internal";
3332 
3333 	/* reinit */
3334 	log_init(argv[0], log_level, SYSLOG_FACILITY_USER, 1);
3335 
3336 	argv += optind;
3337 	argc -= optind;
3338 
3339 	if (sign_op != NULL) {
3340 		if (strncmp(sign_op, "find-principals", 15) == 0) {
3341 			if (ca_key_path == NULL) {
3342 				error("Too few arguments for find-principals:"
3343 				      "missing signature file");
3344 				exit(1);
3345 			}
3346 			if (!have_identity) {
3347 				error("Too few arguments for find-principals:"
3348 				      "missing allowed keys file");
3349 				exit(1);
3350 			}
3351 			return sig_find_principals(ca_key_path, identity_file);
3352 		} else if (strncmp(sign_op, "sign", 4) == 0) {
3353 			if (cert_principals == NULL ||
3354 			    *cert_principals == '\0') {
3355 				error("Too few arguments for sign: "
3356 				    "missing namespace");
3357 				exit(1);
3358 			}
3359 			if (!have_identity) {
3360 				error("Too few arguments for sign: "
3361 				    "missing key");
3362 				exit(1);
3363 			}
3364 			return sig_sign(identity_file, cert_principals,
3365 			    argc, argv);
3366 		} else if (strncmp(sign_op, "check-novalidate", 16) == 0) {
3367 			if (ca_key_path == NULL) {
3368 				error("Too few arguments for check-novalidate: "
3369 				      "missing signature file");
3370 				exit(1);
3371 			}
3372 			return sig_verify(ca_key_path, cert_principals,
3373 			    NULL, NULL, NULL);
3374 		} else if (strncmp(sign_op, "verify", 6) == 0) {
3375 			if (cert_principals == NULL ||
3376 			    *cert_principals == '\0') {
3377 				error("Too few arguments for verify: "
3378 				    "missing namespace");
3379 				exit(1);
3380 			}
3381 			if (ca_key_path == NULL) {
3382 				error("Too few arguments for verify: "
3383 				    "missing signature file");
3384 				exit(1);
3385 			}
3386 			if (!have_identity) {
3387 				error("Too few arguments for sign: "
3388 				    "missing allowed keys file");
3389 				exit(1);
3390 			}
3391 			if (cert_key_id == NULL) {
3392 				error("Too few arguments for verify: "
3393 				    "missing principal ID");
3394 				exit(1);
3395 			}
3396 			return sig_verify(ca_key_path, cert_principals,
3397 			    cert_key_id, identity_file, rr_hostname);
3398 		}
3399 		error("Unsupported operation for -Y: \"%s\"", sign_op);
3400 		usage();
3401 		/* NOTREACHED */
3402 	}
3403 
3404 	if (ca_key_path != NULL) {
3405 		if (argc < 1 && !gen_krl) {
3406 			error("Too few arguments.");
3407 			usage();
3408 		}
3409 	} else if (argc > 0 && !gen_krl && !check_krl &&
3410 	    !do_gen_candidates && !do_screen_candidates) {
3411 		error("Too many arguments.");
3412 		usage();
3413 	}
3414 	if (change_passphrase && change_comment) {
3415 		error("Can only have one of -p and -c.");
3416 		usage();
3417 	}
3418 	if (print_fingerprint && (delete_host || hash_hosts)) {
3419 		error("Cannot use -l with -H or -R.");
3420 		usage();
3421 	}
3422 	if (gen_krl) {
3423 		do_gen_krl(pw, update_krl, ca_key_path,
3424 		    cert_serial, identity_comment, argc, argv);
3425 		return (0);
3426 	}
3427 	if (check_krl) {
3428 		do_check_krl(pw, print_fingerprint, argc, argv);
3429 		return (0);
3430 	}
3431 	if (ca_key_path != NULL) {
3432 		if (cert_key_id == NULL)
3433 			fatal("Must specify key id (-I) when certifying");
3434 		for (i = 0; i < nopts; i++)
3435 			add_cert_option(opts[i]);
3436 		do_ca_sign(pw, ca_key_path, prefer_agent,
3437 		    cert_serial, cert_serial_autoinc, argc, argv);
3438 	}
3439 	if (show_cert)
3440 		do_show_cert(pw);
3441 	if (delete_host || hash_hosts || find_host) {
3442 		do_known_hosts(pw, rr_hostname, find_host,
3443 		    delete_host, hash_hosts);
3444 	}
3445 	if (pkcs11provider != NULL)
3446 		do_download(pw);
3447 	if (download_sk) {
3448 		for (i = 0; i < nopts; i++) {
3449 			if (strncasecmp(opts[i], "device=", 7) == 0) {
3450 				sk_device = xstrdup(opts[i] + 7);
3451 			} else {
3452 				fatal("Option \"%s\" is unsupported for "
3453 				    "FIDO authenticator download", opts[i]);
3454 			}
3455 		}
3456 		return do_download_sk(sk_provider, sk_device);
3457 	}
3458 	if (print_fingerprint || print_bubblebabble)
3459 		do_fingerprint(pw);
3460 	if (change_passphrase)
3461 		do_change_passphrase(pw);
3462 	if (change_comment)
3463 		do_change_comment(pw, identity_comment);
3464 #ifdef WITH_OPENSSL
3465 	if (convert_to)
3466 		do_convert_to(pw);
3467 	if (convert_from)
3468 		do_convert_from(pw);
3469 #else /* WITH_OPENSSL */
3470 	if (convert_to || convert_from)
3471 		fatal("key conversion disabled at compile time");
3472 #endif /* WITH_OPENSSL */
3473 	if (print_public)
3474 		do_print_public(pw);
3475 	if (rr_hostname != NULL) {
3476 		unsigned int n = 0;
3477 
3478 		if (have_identity) {
3479 			n = do_print_resource_record(pw, identity_file,
3480 			    rr_hostname, print_generic);
3481 			if (n == 0)
3482 				fatal("%s: %s", identity_file, strerror(errno));
3483 			exit(0);
3484 		} else {
3485 
3486 			n += do_print_resource_record(pw,
3487 			    _PATH_HOST_RSA_KEY_FILE, rr_hostname,
3488 			    print_generic);
3489 			n += do_print_resource_record(pw,
3490 			    _PATH_HOST_DSA_KEY_FILE, rr_hostname,
3491 			    print_generic);
3492 			n += do_print_resource_record(pw,
3493 			    _PATH_HOST_ECDSA_KEY_FILE, rr_hostname,
3494 			    print_generic);
3495 			n += do_print_resource_record(pw,
3496 			    _PATH_HOST_ED25519_KEY_FILE, rr_hostname,
3497 			    print_generic);
3498 			n += do_print_resource_record(pw,
3499 			    _PATH_HOST_XMSS_KEY_FILE, rr_hostname,
3500 			    print_generic);
3501 			if (n == 0)
3502 				fatal("no keys found.");
3503 			exit(0);
3504 		}
3505 	}
3506 
3507 	if (do_gen_candidates || do_screen_candidates) {
3508 		if (argc <= 0)
3509 			fatal("No output file specified");
3510 		else if (argc > 1)
3511 			fatal("Too many output files specified");
3512 	}
3513 	if (do_gen_candidates) {
3514 		do_moduli_gen(argv[0], opts, nopts);
3515 		return 0;
3516 	}
3517 	if (do_screen_candidates) {
3518 		do_moduli_screen(argv[0], opts, nopts);
3519 		return 0;
3520 	}
3521 
3522 	if (gen_all_hostkeys) {
3523 		do_gen_all_hostkeys(pw);
3524 		return (0);
3525 	}
3526 
3527 	if (key_type_name == NULL)
3528 		key_type_name = DEFAULT_KEY_TYPE_NAME;
3529 
3530 	type = sshkey_type_from_name(key_type_name);
3531 	type_bits_valid(type, key_type_name, &bits);
3532 
3533 	if (!quiet)
3534 		printf("Generating public/private %s key pair.\n",
3535 		    key_type_name);
3536 	switch (type) {
3537 	case KEY_ECDSA_SK:
3538 	case KEY_ED25519_SK:
3539 		for (i = 0; i < nopts; i++) {
3540 			if (strcasecmp(opts[i], "no-touch-required") == 0) {
3541 				sk_flags &= ~SSH_SK_USER_PRESENCE_REQD;
3542 			} else if (strcasecmp(opts[i], "verify-required") == 0) {
3543 				sk_flags |= SSH_SK_USER_VERIFICATION_REQD;
3544 			} else if (strcasecmp(opts[i], "resident") == 0) {
3545 				sk_flags |= SSH_SK_RESIDENT_KEY;
3546 			} else if (strncasecmp(opts[i], "device=", 7) == 0) {
3547 				sk_device = xstrdup(opts[i] + 7);
3548 			} else if (strncasecmp(opts[i], "user=", 5) == 0) {
3549 				sk_user = xstrdup(opts[i] + 5);
3550 			} else if (strncasecmp(opts[i], "challenge=", 10) == 0) {
3551 				if ((r = sshbuf_load_file(opts[i] + 10,
3552 				    &challenge)) != 0) {
3553 					fatal_r(r, "Unable to load FIDO "
3554 					    "enrollment challenge \"%s\"",
3555 					    opts[i] + 10);
3556 				}
3557 			} else if (strncasecmp(opts[i],
3558 			    "write-attestation=", 18) == 0) {
3559 				sk_attestation_path = opts[i] + 18;
3560 			} else if (strncasecmp(opts[i],
3561 			    "application=", 12) == 0) {
3562 				sk_application = xstrdup(opts[i] + 12);
3563 				if (strncmp(sk_application, "ssh:", 4) != 0) {
3564 					fatal("FIDO application string must "
3565 					    "begin with \"ssh:\"");
3566 				}
3567 			} else {
3568 				fatal("Option \"%s\" is unsupported for "
3569 				    "FIDO authenticator enrollment", opts[i]);
3570 			}
3571 		}
3572 		if (!quiet) {
3573 			printf("You may need to touch your authenticator "
3574 			    "to authorize key generation.\n");
3575 		}
3576 		if ((attest = sshbuf_new()) == NULL)
3577 			fatal("sshbuf_new failed");
3578 		if ((sk_flags &
3579 		    (SSH_SK_USER_VERIFICATION_REQD|SSH_SK_RESIDENT_KEY))) {
3580 			passphrase = read_passphrase("Enter PIN for "
3581 			    "authenticator: ", RP_ALLOW_STDIN);
3582 		} else {
3583 			passphrase = NULL;
3584 		}
3585 		for (i = 0 ; ; i++) {
3586 			fflush(stdout);
3587 			r = sshsk_enroll(type, sk_provider, sk_device,
3588 			    sk_application == NULL ? "ssh:" : sk_application,
3589 			    sk_user, sk_flags, passphrase, challenge,
3590 			    &private, attest);
3591 			if (r == 0)
3592 				break;
3593 			if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
3594 				fatal_r(r, "Key enrollment failed");
3595 			else if (passphrase != NULL) {
3596 				error("PIN incorrect");
3597 				freezero(passphrase, strlen(passphrase));
3598 				passphrase = NULL;
3599 			}
3600 			if (i >= 3)
3601 				fatal("Too many incorrect PINs");
3602 			passphrase = read_passphrase("Enter PIN for "
3603 			    "authenticator: ", RP_ALLOW_STDIN);
3604 			if (!quiet) {
3605 				printf("You may need to touch your "
3606 				    "authenticator (again) to authorize "
3607 				    "key generation.\n");
3608 			}
3609 		}
3610 		if (passphrase != NULL) {
3611 			freezero(passphrase, strlen(passphrase));
3612 			passphrase = NULL;
3613 		}
3614 		break;
3615 	default:
3616 		if ((r = sshkey_generate(type, bits, &private)) != 0)
3617 			fatal("sshkey_generate failed");
3618 		break;
3619 	}
3620 	if ((r = sshkey_from_private(private, &public)) != 0)
3621 		fatal_r(r, "sshkey_from_private");
3622 
3623 	if (!have_identity)
3624 		ask_filename(pw, "Enter file in which to save the key");
3625 
3626 	/* Create ~/.ssh directory if it doesn't already exist. */
3627 	hostfile_create_user_ssh_dir(identity_file, !quiet);
3628 
3629 	/* If the file already exists, ask the user to confirm. */
3630 	if (!confirm_overwrite(identity_file))
3631 		exit(1);
3632 
3633 	/* Determine the passphrase for the private key */
3634 	passphrase = private_key_passphrase();
3635 	if (identity_comment) {
3636 		strlcpy(comment, identity_comment, sizeof(comment));
3637 	} else {
3638 		/* Create default comment field for the passphrase. */
3639 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
3640 	}
3641 
3642 	/* Save the key with the given passphrase and comment. */
3643 	if ((r = sshkey_save_private(private, identity_file, passphrase,
3644 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
3645 		error_r(r, "Saving key \"%s\" failed", identity_file);
3646 		freezero(passphrase, strlen(passphrase));
3647 		exit(1);
3648 	}
3649 	freezero(passphrase, strlen(passphrase));
3650 	sshkey_free(private);
3651 
3652 	if (!quiet) {
3653 		printf("Your identification has been saved in %s\n",
3654 		    identity_file);
3655 	}
3656 
3657 	strlcat(identity_file, ".pub", sizeof(identity_file));
3658 	if ((r = sshkey_save_public(public, identity_file, comment)) != 0)
3659 		fatal_r(r, "Unable to save public key to %s", identity_file);
3660 
3661 	if (!quiet) {
3662 		fp = sshkey_fingerprint(public, fingerprint_hash,
3663 		    SSH_FP_DEFAULT);
3664 		ra = sshkey_fingerprint(public, fingerprint_hash,
3665 		    SSH_FP_RANDOMART);
3666 		if (fp == NULL || ra == NULL)
3667 			fatal("sshkey_fingerprint failed");
3668 		printf("Your public key has been saved in %s\n",
3669 		    identity_file);
3670 		printf("The key fingerprint is:\n");
3671 		printf("%s %s\n", fp, comment);
3672 		printf("The key's randomart image is:\n");
3673 		printf("%s\n", ra);
3674 		free(ra);
3675 		free(fp);
3676 	}
3677 
3678 	if (sk_attestation_path != NULL)
3679 		save_attestation(attest, sk_attestation_path);
3680 
3681 	sshbuf_free(attest);
3682 	sshkey_free(public);
3683 
3684 	exit(0);
3685 }
3686