xref: /freebsd/crypto/openssh/ssh-keygen.c (revision 942815c54820783d3d4f7f6faa71ab7919b5f0e5)
1 /* $OpenBSD: ssh-keygen.c,v 1.461 2022/12/04 23:50:49 cheloha 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 "includes.h"
16 
17 #include <sys/types.h>
18 #include <sys/socket.h>
19 #include <sys/stat.h>
20 
21 #ifdef WITH_OPENSSL
22 #include <openssl/evp.h>
23 #include <openssl/pem.h>
24 #include "openbsd-compat/openssl-compat.h"
25 #endif
26 
27 #ifdef HAVE_STDINT_H
28 # include <stdint.h>
29 #endif
30 #include <errno.h>
31 #include <fcntl.h>
32 #include <netdb.h>
33 #ifdef HAVE_PATHS_H
34 # include <paths.h>
35 #endif
36 #include <pwd.h>
37 #include <stdarg.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 #include <limits.h>
43 #include <locale.h>
44 #include <time.h>
45 
46 #include "xmalloc.h"
47 #include "sshkey.h"
48 #include "authfile.h"
49 #include "sshbuf.h"
50 #include "pathnames.h"
51 #include "log.h"
52 #include "misc.h"
53 #include "match.h"
54 #include "hostfile.h"
55 #include "dns.h"
56 #include "ssh.h"
57 #include "ssh2.h"
58 #include "ssherr.h"
59 #include "ssh-pkcs11.h"
60 #include "atomicio.h"
61 #include "krl.h"
62 #include "digest.h"
63 #include "utf8.h"
64 #include "authfd.h"
65 #include "sshsig.h"
66 #include "ssh-sk.h"
67 #include "sk-api.h" /* XXX for SSH_SK_USER_PRESENCE_REQD; remove */
68 #include "cipher.h"
69 
70 #ifdef WITH_OPENSSL
71 # define DEFAULT_KEY_TYPE_NAME "rsa"
72 #else
73 # define DEFAULT_KEY_TYPE_NAME "ed25519"
74 #endif
75 
76 /*
77  * Default number of bits in the RSA, DSA and ECDSA keys.  These value can be
78  * overridden on the command line.
79  *
80  * These values, with the exception of DSA, provide security equivalent to at
81  * least 128 bits of security according to NIST Special Publication 800-57:
82  * Recommendation for Key Management Part 1 rev 4 section 5.6.1.
83  * For DSA it (and FIPS-186-4 section 4.2) specifies that the only size for
84  * which a 160bit hash is acceptable is 1kbit, and since ssh-dss specifies only
85  * SHA1 we limit the DSA key size 1k bits.
86  */
87 #define DEFAULT_BITS		3072
88 #define DEFAULT_BITS_DSA	1024
89 #define DEFAULT_BITS_ECDSA	256
90 
91 static int quiet = 0;
92 
93 /* Flag indicating that we just want to see the key fingerprint */
94 static int print_fingerprint = 0;
95 static int print_bubblebabble = 0;
96 
97 /* Hash algorithm to use for fingerprints. */
98 static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
99 
100 /* The identity file name, given on the command line or entered by the user. */
101 static char identity_file[PATH_MAX];
102 static int have_identity = 0;
103 
104 /* This is set to the passphrase if given on the command line. */
105 static char *identity_passphrase = NULL;
106 
107 /* This is set to the new passphrase if given on the command line. */
108 static char *identity_new_passphrase = NULL;
109 
110 /* Key type when certifying */
111 static u_int cert_key_type = SSH2_CERT_TYPE_USER;
112 
113 /* "key ID" of signed key */
114 static char *cert_key_id = NULL;
115 
116 /* Comma-separated list of principal names for certifying keys */
117 static char *cert_principals = NULL;
118 
119 /* Validity period for certificates */
120 static u_int64_t cert_valid_from = 0;
121 static u_int64_t cert_valid_to = ~0ULL;
122 
123 /* Certificate options */
124 #define CERTOPT_X_FWD				(1)
125 #define CERTOPT_AGENT_FWD			(1<<1)
126 #define CERTOPT_PORT_FWD			(1<<2)
127 #define CERTOPT_PTY				(1<<3)
128 #define CERTOPT_USER_RC				(1<<4)
129 #define CERTOPT_NO_REQUIRE_USER_PRESENCE	(1<<5)
130 #define CERTOPT_REQUIRE_VERIFY			(1<<6)
131 #define CERTOPT_DEFAULT	(CERTOPT_X_FWD|CERTOPT_AGENT_FWD| \
132 			 CERTOPT_PORT_FWD|CERTOPT_PTY|CERTOPT_USER_RC)
133 static u_int32_t certflags_flags = CERTOPT_DEFAULT;
134 static char *certflags_command = NULL;
135 static char *certflags_src_addr = NULL;
136 
137 /* Arbitrary extensions specified by user */
138 struct cert_ext {
139 	char *key;
140 	char *val;
141 	int crit;
142 };
143 static struct cert_ext *cert_ext;
144 static size_t ncert_ext;
145 
146 /* Conversion to/from various formats */
147 enum {
148 	FMT_RFC4716,
149 	FMT_PKCS8,
150 	FMT_PEM
151 } convert_format = FMT_RFC4716;
152 
153 static char *key_type_name = NULL;
154 
155 /* Load key from this PKCS#11 provider */
156 static char *pkcs11provider = NULL;
157 
158 /* FIDO/U2F provider to use */
159 static char *sk_provider = NULL;
160 
161 /* Format for writing private keys */
162 static int private_key_format = SSHKEY_PRIVATE_OPENSSH;
163 
164 /* Cipher for new-format private keys */
165 static char *openssh_format_cipher = NULL;
166 
167 /* Number of KDF rounds to derive new format keys. */
168 static int rounds = 0;
169 
170 /* argv0 */
171 extern char *__progname;
172 
173 static char hostname[NI_MAXHOST];
174 
175 #ifdef WITH_OPENSSL
176 /* moduli.c */
177 int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
178 int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
179     unsigned long);
180 #endif
181 
182 static void
183 type_bits_valid(int type, const char *name, u_int32_t *bitsp)
184 {
185 	if (type == KEY_UNSPEC)
186 		fatal("unknown key type %s", key_type_name);
187 	if (*bitsp == 0) {
188 #ifdef WITH_OPENSSL
189 		int nid;
190 
191 		switch(type) {
192 		case KEY_DSA:
193 			*bitsp = DEFAULT_BITS_DSA;
194 			break;
195 		case KEY_ECDSA:
196 			if (name != NULL &&
197 			    (nid = sshkey_ecdsa_nid_from_name(name)) > 0)
198 				*bitsp = sshkey_curve_nid_to_bits(nid);
199 			if (*bitsp == 0)
200 				*bitsp = DEFAULT_BITS_ECDSA;
201 			break;
202 		case KEY_RSA:
203 			*bitsp = DEFAULT_BITS;
204 			break;
205 		}
206 #endif
207 	}
208 #ifdef WITH_OPENSSL
209 	switch (type) {
210 	case KEY_DSA:
211 		if (*bitsp != 1024)
212 			fatal("Invalid DSA key length: must be 1024 bits");
213 		break;
214 	case KEY_RSA:
215 		if (*bitsp < SSH_RSA_MINIMUM_MODULUS_SIZE)
216 			fatal("Invalid RSA key length: minimum is %d bits",
217 			    SSH_RSA_MINIMUM_MODULUS_SIZE);
218 		else if (*bitsp > OPENSSL_RSA_MAX_MODULUS_BITS)
219 			fatal("Invalid RSA key length: maximum is %d bits",
220 			    OPENSSL_RSA_MAX_MODULUS_BITS);
221 		break;
222 	case KEY_ECDSA:
223 		if (sshkey_ecdsa_bits_to_nid(*bitsp) == -1)
224 #ifdef OPENSSL_HAS_NISTP521
225 			fatal("Invalid ECDSA key length: valid lengths are "
226 			    "256, 384 or 521 bits");
227 #else
228 			fatal("Invalid ECDSA key length: valid lengths are "
229 			    "256 or 384 bits");
230 #endif
231 	}
232 #endif
233 }
234 
235 /*
236  * Checks whether a file exists and, if so, asks the user whether they wish
237  * to overwrite it.
238  * Returns nonzero if the file does not already exist or if the user agrees to
239  * overwrite, or zero otherwise.
240  */
241 static int
242 confirm_overwrite(const char *filename)
243 {
244 	char yesno[3];
245 	struct stat st;
246 
247 	if (stat(filename, &st) != 0)
248 		return 1;
249 	printf("%s already exists.\n", filename);
250 	printf("Overwrite (y/n)? ");
251 	fflush(stdout);
252 	if (fgets(yesno, sizeof(yesno), stdin) == NULL)
253 		return 0;
254 	if (yesno[0] != 'y' && yesno[0] != 'Y')
255 		return 0;
256 	return 1;
257 }
258 
259 static void
260 ask_filename(struct passwd *pw, const char *prompt)
261 {
262 	char buf[1024];
263 	char *name = NULL;
264 
265 	if (key_type_name == NULL)
266 		name = _PATH_SSH_CLIENT_ID_RSA;
267 	else {
268 		switch (sshkey_type_from_name(key_type_name)) {
269 		case KEY_DSA_CERT:
270 		case KEY_DSA:
271 			name = _PATH_SSH_CLIENT_ID_DSA;
272 			break;
273 #ifdef OPENSSL_HAS_ECC
274 		case KEY_ECDSA_CERT:
275 		case KEY_ECDSA:
276 			name = _PATH_SSH_CLIENT_ID_ECDSA;
277 			break;
278 		case KEY_ECDSA_SK_CERT:
279 		case KEY_ECDSA_SK:
280 			name = _PATH_SSH_CLIENT_ID_ECDSA_SK;
281 			break;
282 #endif
283 		case KEY_RSA_CERT:
284 		case KEY_RSA:
285 			name = _PATH_SSH_CLIENT_ID_RSA;
286 			break;
287 		case KEY_ED25519:
288 		case KEY_ED25519_CERT:
289 			name = _PATH_SSH_CLIENT_ID_ED25519;
290 			break;
291 		case KEY_ED25519_SK:
292 		case KEY_ED25519_SK_CERT:
293 			name = _PATH_SSH_CLIENT_ID_ED25519_SK;
294 			break;
295 		case KEY_XMSS:
296 		case KEY_XMSS_CERT:
297 			name = _PATH_SSH_CLIENT_ID_XMSS;
298 			break;
299 		default:
300 			fatal("bad key type");
301 		}
302 	}
303 	snprintf(identity_file, sizeof(identity_file),
304 	    "%s/%s", pw->pw_dir, name);
305 	printf("%s (%s): ", prompt, identity_file);
306 	fflush(stdout);
307 	if (fgets(buf, sizeof(buf), stdin) == NULL)
308 		exit(1);
309 	buf[strcspn(buf, "\n")] = '\0';
310 	if (strcmp(buf, "") != 0)
311 		strlcpy(identity_file, buf, sizeof(identity_file));
312 	have_identity = 1;
313 }
314 
315 static struct sshkey *
316 load_identity(const char *filename, char **commentp)
317 {
318 	char *pass;
319 	struct sshkey *prv;
320 	int r;
321 
322 	if (commentp != NULL)
323 		*commentp = NULL;
324 	if ((r = sshkey_load_private(filename, "", &prv, commentp)) == 0)
325 		return prv;
326 	if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
327 		fatal_r(r, "Load key \"%s\"", filename);
328 	if (identity_passphrase)
329 		pass = xstrdup(identity_passphrase);
330 	else
331 		pass = read_passphrase("Enter passphrase: ", RP_ALLOW_STDIN);
332 	r = sshkey_load_private(filename, pass, &prv, commentp);
333 	freezero(pass, strlen(pass));
334 	if (r != 0)
335 		fatal_r(r, "Load key \"%s\"", filename);
336 	return prv;
337 }
338 
339 #define SSH_COM_PUBLIC_BEGIN		"---- BEGIN SSH2 PUBLIC KEY ----"
340 #define SSH_COM_PUBLIC_END		"---- END SSH2 PUBLIC KEY ----"
341 #define SSH_COM_PRIVATE_BEGIN		"---- BEGIN SSH2 ENCRYPTED PRIVATE KEY ----"
342 #define	SSH_COM_PRIVATE_KEY_MAGIC	0x3f6ff9eb
343 
344 #ifdef WITH_OPENSSL
345 static void
346 do_convert_to_ssh2(struct passwd *pw, struct sshkey *k)
347 {
348 	struct sshbuf *b;
349 	char comment[61], *b64;
350 	int r;
351 
352 	if ((b = sshbuf_new()) == NULL)
353 		fatal_f("sshbuf_new failed");
354 	if ((r = sshkey_putb(k, b)) != 0)
355 		fatal_fr(r, "put key");
356 	if ((b64 = sshbuf_dtob64_string(b, 1)) == NULL)
357 		fatal_f("sshbuf_dtob64_string failed");
358 
359 	/* Comment + surrounds must fit into 72 chars (RFC 4716 sec 3.3) */
360 	snprintf(comment, sizeof(comment),
361 	    "%u-bit %s, converted by %s@%s from OpenSSH",
362 	    sshkey_size(k), sshkey_type(k),
363 	    pw->pw_name, hostname);
364 
365 	sshkey_free(k);
366 	sshbuf_free(b);
367 
368 	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_BEGIN);
369 	fprintf(stdout, "Comment: \"%s\"\n%s", comment, b64);
370 	fprintf(stdout, "%s\n", SSH_COM_PUBLIC_END);
371 	free(b64);
372 	exit(0);
373 }
374 
375 static void
376 do_convert_to_pkcs8(struct sshkey *k)
377 {
378 	switch (sshkey_type_plain(k->type)) {
379 	case KEY_RSA:
380 		if (!PEM_write_RSA_PUBKEY(stdout, k->rsa))
381 			fatal("PEM_write_RSA_PUBKEY failed");
382 		break;
383 	case KEY_DSA:
384 		if (!PEM_write_DSA_PUBKEY(stdout, k->dsa))
385 			fatal("PEM_write_DSA_PUBKEY failed");
386 		break;
387 #ifdef OPENSSL_HAS_ECC
388 	case KEY_ECDSA:
389 		if (!PEM_write_EC_PUBKEY(stdout, k->ecdsa))
390 			fatal("PEM_write_EC_PUBKEY failed");
391 		break;
392 #endif
393 	default:
394 		fatal_f("unsupported key type %s", sshkey_type(k));
395 	}
396 	exit(0);
397 }
398 
399 static void
400 do_convert_to_pem(struct sshkey *k)
401 {
402 	switch (sshkey_type_plain(k->type)) {
403 	case KEY_RSA:
404 		if (!PEM_write_RSAPublicKey(stdout, k->rsa))
405 			fatal("PEM_write_RSAPublicKey failed");
406 		break;
407 	case KEY_DSA:
408 		if (!PEM_write_DSA_PUBKEY(stdout, k->dsa))
409 			fatal("PEM_write_DSA_PUBKEY failed");
410 		break;
411 #ifdef OPENSSL_HAS_ECC
412 	case KEY_ECDSA:
413 		if (!PEM_write_EC_PUBKEY(stdout, k->ecdsa))
414 			fatal("PEM_write_EC_PUBKEY failed");
415 		break;
416 #endif
417 	default:
418 		fatal_f("unsupported key type %s", sshkey_type(k));
419 	}
420 	exit(0);
421 }
422 
423 static void
424 do_convert_to(struct passwd *pw)
425 {
426 	struct sshkey *k;
427 	struct stat st;
428 	int r;
429 
430 	if (!have_identity)
431 		ask_filename(pw, "Enter file in which the key is");
432 	if (stat(identity_file, &st) == -1)
433 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
434 	if ((r = sshkey_load_public(identity_file, &k, NULL)) != 0)
435 		k = load_identity(identity_file, NULL);
436 	switch (convert_format) {
437 	case FMT_RFC4716:
438 		do_convert_to_ssh2(pw, k);
439 		break;
440 	case FMT_PKCS8:
441 		do_convert_to_pkcs8(k);
442 		break;
443 	case FMT_PEM:
444 		do_convert_to_pem(k);
445 		break;
446 	default:
447 		fatal_f("unknown key format %d", convert_format);
448 	}
449 	exit(0);
450 }
451 
452 /*
453  * This is almost exactly the bignum1 encoding, but with 32 bit for length
454  * instead of 16.
455  */
456 static void
457 buffer_get_bignum_bits(struct sshbuf *b, BIGNUM *value)
458 {
459 	u_int bytes, bignum_bits;
460 	int r;
461 
462 	if ((r = sshbuf_get_u32(b, &bignum_bits)) != 0)
463 		fatal_fr(r, "parse");
464 	bytes = (bignum_bits + 7) / 8;
465 	if (sshbuf_len(b) < bytes)
466 		fatal_f("input buffer too small: need %d have %zu",
467 		    bytes, sshbuf_len(b));
468 	if (BN_bin2bn(sshbuf_ptr(b), bytes, value) == NULL)
469 		fatal_f("BN_bin2bn failed");
470 	if ((r = sshbuf_consume(b, bytes)) != 0)
471 		fatal_fr(r, "consume");
472 }
473 
474 static struct sshkey *
475 do_convert_private_ssh2(struct sshbuf *b)
476 {
477 	struct sshkey *key = NULL;
478 	char *type, *cipher;
479 	u_char e1, e2, e3, *sig = NULL, data[] = "abcde12345";
480 	int r, rlen, ktype;
481 	u_int magic, i1, i2, i3, i4;
482 	size_t slen;
483 	u_long e;
484 	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL;
485 	BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL;
486 	BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL;
487 	BIGNUM *rsa_p = NULL, *rsa_q = NULL, *rsa_iqmp = NULL;
488 
489 	if ((r = sshbuf_get_u32(b, &magic)) != 0)
490 		fatal_fr(r, "parse magic");
491 
492 	if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
493 		error("bad magic 0x%x != 0x%x", magic,
494 		    SSH_COM_PRIVATE_KEY_MAGIC);
495 		return NULL;
496 	}
497 	if ((r = sshbuf_get_u32(b, &i1)) != 0 ||
498 	    (r = sshbuf_get_cstring(b, &type, NULL)) != 0 ||
499 	    (r = sshbuf_get_cstring(b, &cipher, NULL)) != 0 ||
500 	    (r = sshbuf_get_u32(b, &i2)) != 0 ||
501 	    (r = sshbuf_get_u32(b, &i3)) != 0 ||
502 	    (r = sshbuf_get_u32(b, &i4)) != 0)
503 		fatal_fr(r, "parse");
504 	debug("ignore (%d %d %d %d)", i1, i2, i3, i4);
505 	if (strcmp(cipher, "none") != 0) {
506 		error("unsupported cipher %s", cipher);
507 		free(cipher);
508 		free(type);
509 		return NULL;
510 	}
511 	free(cipher);
512 
513 	if (strstr(type, "dsa")) {
514 		ktype = KEY_DSA;
515 	} else if (strstr(type, "rsa")) {
516 		ktype = KEY_RSA;
517 	} else {
518 		free(type);
519 		return NULL;
520 	}
521 	if ((key = sshkey_new(ktype)) == NULL)
522 		fatal("sshkey_new failed");
523 	free(type);
524 
525 	switch (key->type) {
526 	case KEY_DSA:
527 		if ((dsa_p = BN_new()) == NULL ||
528 		    (dsa_q = BN_new()) == NULL ||
529 		    (dsa_g = BN_new()) == NULL ||
530 		    (dsa_pub_key = BN_new()) == NULL ||
531 		    (dsa_priv_key = BN_new()) == NULL)
532 			fatal_f("BN_new");
533 		buffer_get_bignum_bits(b, dsa_p);
534 		buffer_get_bignum_bits(b, dsa_g);
535 		buffer_get_bignum_bits(b, dsa_q);
536 		buffer_get_bignum_bits(b, dsa_pub_key);
537 		buffer_get_bignum_bits(b, dsa_priv_key);
538 		if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g))
539 			fatal_f("DSA_set0_pqg failed");
540 		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
541 		if (!DSA_set0_key(key->dsa, dsa_pub_key, dsa_priv_key))
542 			fatal_f("DSA_set0_key failed");
543 		dsa_pub_key = dsa_priv_key = NULL; /* transferred */
544 		break;
545 	case KEY_RSA:
546 		if ((r = sshbuf_get_u8(b, &e1)) != 0 ||
547 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e2)) != 0) ||
548 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e3)) != 0))
549 			fatal_fr(r, "parse RSA");
550 		e = e1;
551 		debug("e %lx", e);
552 		if (e < 30) {
553 			e <<= 8;
554 			e += e2;
555 			debug("e %lx", e);
556 			e <<= 8;
557 			e += e3;
558 			debug("e %lx", e);
559 		}
560 		if ((rsa_e = BN_new()) == NULL)
561 			fatal_f("BN_new");
562 		if (!BN_set_word(rsa_e, e)) {
563 			BN_clear_free(rsa_e);
564 			sshkey_free(key);
565 			return NULL;
566 		}
567 		if ((rsa_n = BN_new()) == NULL ||
568 		    (rsa_d = BN_new()) == NULL ||
569 		    (rsa_p = BN_new()) == NULL ||
570 		    (rsa_q = BN_new()) == NULL ||
571 		    (rsa_iqmp = BN_new()) == NULL)
572 			fatal_f("BN_new");
573 		buffer_get_bignum_bits(b, rsa_d);
574 		buffer_get_bignum_bits(b, rsa_n);
575 		buffer_get_bignum_bits(b, rsa_iqmp);
576 		buffer_get_bignum_bits(b, rsa_q);
577 		buffer_get_bignum_bits(b, rsa_p);
578 		if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, rsa_d))
579 			fatal_f("RSA_set0_key failed");
580 		rsa_n = rsa_e = rsa_d = NULL; /* transferred */
581 		if (!RSA_set0_factors(key->rsa, rsa_p, rsa_q))
582 			fatal_f("RSA_set0_factors failed");
583 		rsa_p = rsa_q = NULL; /* transferred */
584 		if ((r = ssh_rsa_complete_crt_parameters(key, rsa_iqmp)) != 0)
585 			fatal_fr(r, "generate RSA parameters");
586 		BN_clear_free(rsa_iqmp);
587 		break;
588 	}
589 	rlen = sshbuf_len(b);
590 	if (rlen != 0)
591 		error_f("remaining bytes in key blob %d", rlen);
592 
593 	/* try the key */
594 	if ((r = sshkey_sign(key, &sig, &slen, data, sizeof(data),
595 	    NULL, NULL, NULL, 0)) != 0)
596 		error_fr(r, "signing with converted key failed");
597 	else if ((r = sshkey_verify(key, sig, slen, data, sizeof(data),
598 	    NULL, 0, NULL)) != 0)
599 		error_fr(r, "verification with converted key failed");
600 	if (r != 0) {
601 		sshkey_free(key);
602 		free(sig);
603 		return NULL;
604 	}
605 	free(sig);
606 	return key;
607 }
608 
609 static int
610 get_line(FILE *fp, char *line, size_t len)
611 {
612 	int c;
613 	size_t pos = 0;
614 
615 	line[0] = '\0';
616 	while ((c = fgetc(fp)) != EOF) {
617 		if (pos >= len - 1)
618 			fatal("input line too long.");
619 		switch (c) {
620 		case '\r':
621 			c = fgetc(fp);
622 			if (c != EOF && c != '\n' && ungetc(c, fp) == EOF)
623 				fatal("unget: %s", strerror(errno));
624 			return pos;
625 		case '\n':
626 			return pos;
627 		}
628 		line[pos++] = c;
629 		line[pos] = '\0';
630 	}
631 	/* We reached EOF */
632 	return -1;
633 }
634 
635 static void
636 do_convert_from_ssh2(struct passwd *pw, struct sshkey **k, int *private)
637 {
638 	int r, blen, escaped = 0;
639 	u_int len;
640 	char line[1024];
641 	struct sshbuf *buf;
642 	char encoded[8096];
643 	FILE *fp;
644 
645 	if ((buf = sshbuf_new()) == NULL)
646 		fatal("sshbuf_new failed");
647 	if ((fp = fopen(identity_file, "r")) == NULL)
648 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
649 	encoded[0] = '\0';
650 	while ((blen = get_line(fp, line, sizeof(line))) != -1) {
651 		if (blen > 0 && line[blen - 1] == '\\')
652 			escaped++;
653 		if (strncmp(line, "----", 4) == 0 ||
654 		    strstr(line, ": ") != NULL) {
655 			if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
656 				*private = 1;
657 			if (strstr(line, " END ") != NULL) {
658 				break;
659 			}
660 			/* fprintf(stderr, "ignore: %s", line); */
661 			continue;
662 		}
663 		if (escaped) {
664 			escaped--;
665 			/* fprintf(stderr, "escaped: %s", line); */
666 			continue;
667 		}
668 		strlcat(encoded, line, sizeof(encoded));
669 	}
670 	len = strlen(encoded);
671 	if (((len % 4) == 3) &&
672 	    (encoded[len-1] == '=') &&
673 	    (encoded[len-2] == '=') &&
674 	    (encoded[len-3] == '='))
675 		encoded[len-3] = '\0';
676 	if ((r = sshbuf_b64tod(buf, encoded)) != 0)
677 		fatal_fr(r, "base64 decode");
678 	if (*private) {
679 		if ((*k = do_convert_private_ssh2(buf)) == NULL)
680 			fatal_f("private key conversion failed");
681 	} else if ((r = sshkey_fromb(buf, k)) != 0)
682 		fatal_fr(r, "parse key");
683 	sshbuf_free(buf);
684 	fclose(fp);
685 }
686 
687 static void
688 do_convert_from_pkcs8(struct sshkey **k, int *private)
689 {
690 	EVP_PKEY *pubkey;
691 	FILE *fp;
692 
693 	if ((fp = fopen(identity_file, "r")) == NULL)
694 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
695 	if ((pubkey = PEM_read_PUBKEY(fp, NULL, NULL, NULL)) == NULL) {
696 		fatal_f("%s is not a recognised public key format",
697 		    identity_file);
698 	}
699 	fclose(fp);
700 	switch (EVP_PKEY_base_id(pubkey)) {
701 	case EVP_PKEY_RSA:
702 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
703 			fatal("sshkey_new failed");
704 		(*k)->type = KEY_RSA;
705 		(*k)->rsa = EVP_PKEY_get1_RSA(pubkey);
706 		break;
707 	case EVP_PKEY_DSA:
708 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
709 			fatal("sshkey_new failed");
710 		(*k)->type = KEY_DSA;
711 		(*k)->dsa = EVP_PKEY_get1_DSA(pubkey);
712 		break;
713 #ifdef OPENSSL_HAS_ECC
714 	case EVP_PKEY_EC:
715 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
716 			fatal("sshkey_new failed");
717 		(*k)->type = KEY_ECDSA;
718 		(*k)->ecdsa = EVP_PKEY_get1_EC_KEY(pubkey);
719 		(*k)->ecdsa_nid = sshkey_ecdsa_key_to_nid((*k)->ecdsa);
720 		break;
721 #endif
722 	default:
723 		fatal_f("unsupported pubkey type %d",
724 		    EVP_PKEY_base_id(pubkey));
725 	}
726 	EVP_PKEY_free(pubkey);
727 	return;
728 }
729 
730 static void
731 do_convert_from_pem(struct sshkey **k, int *private)
732 {
733 	FILE *fp;
734 	RSA *rsa;
735 
736 	if ((fp = fopen(identity_file, "r")) == NULL)
737 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
738 	if ((rsa = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL)) != NULL) {
739 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
740 			fatal("sshkey_new failed");
741 		(*k)->type = KEY_RSA;
742 		(*k)->rsa = rsa;
743 		fclose(fp);
744 		return;
745 	}
746 	fatal_f("unrecognised raw private key format");
747 }
748 
749 static void
750 do_convert_from(struct passwd *pw)
751 {
752 	struct sshkey *k = NULL;
753 	int r, private = 0, ok = 0;
754 	struct stat st;
755 
756 	if (!have_identity)
757 		ask_filename(pw, "Enter file in which the key is");
758 	if (stat(identity_file, &st) == -1)
759 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
760 
761 	switch (convert_format) {
762 	case FMT_RFC4716:
763 		do_convert_from_ssh2(pw, &k, &private);
764 		break;
765 	case FMT_PKCS8:
766 		do_convert_from_pkcs8(&k, &private);
767 		break;
768 	case FMT_PEM:
769 		do_convert_from_pem(&k, &private);
770 		break;
771 	default:
772 		fatal_f("unknown key format %d", convert_format);
773 	}
774 
775 	if (!private) {
776 		if ((r = sshkey_write(k, stdout)) == 0)
777 			ok = 1;
778 		if (ok)
779 			fprintf(stdout, "\n");
780 	} else {
781 		switch (k->type) {
782 		case KEY_DSA:
783 			ok = PEM_write_DSAPrivateKey(stdout, k->dsa, NULL,
784 			    NULL, 0, NULL, NULL);
785 			break;
786 #ifdef OPENSSL_HAS_ECC
787 		case KEY_ECDSA:
788 			ok = PEM_write_ECPrivateKey(stdout, k->ecdsa, NULL,
789 			    NULL, 0, NULL, NULL);
790 			break;
791 #endif
792 		case KEY_RSA:
793 			ok = PEM_write_RSAPrivateKey(stdout, k->rsa, NULL,
794 			    NULL, 0, NULL, NULL);
795 			break;
796 		default:
797 			fatal_f("unsupported key type %s", sshkey_type(k));
798 		}
799 	}
800 
801 	if (!ok)
802 		fatal("key write failed");
803 	sshkey_free(k);
804 	exit(0);
805 }
806 #endif
807 
808 static void
809 do_print_public(struct passwd *pw)
810 {
811 	struct sshkey *prv;
812 	struct stat st;
813 	int r;
814 	char *comment = NULL;
815 
816 	if (!have_identity)
817 		ask_filename(pw, "Enter file in which the key is");
818 	if (stat(identity_file, &st) == -1)
819 		fatal("%s: %s", identity_file, strerror(errno));
820 	prv = load_identity(identity_file, &comment);
821 	if ((r = sshkey_write(prv, stdout)) != 0)
822 		fatal_fr(r, "write key");
823 	if (comment != NULL && *comment != '\0')
824 		fprintf(stdout, " %s", comment);
825 	fprintf(stdout, "\n");
826 	if (sshkey_is_sk(prv)) {
827 		debug("sk_application: \"%s\", sk_flags 0x%02x",
828 			prv->sk_application, prv->sk_flags);
829 	}
830 	sshkey_free(prv);
831 	free(comment);
832 	exit(0);
833 }
834 
835 static void
836 do_download(struct passwd *pw)
837 {
838 #ifdef ENABLE_PKCS11
839 	struct sshkey **keys = NULL;
840 	int i, nkeys;
841 	enum sshkey_fp_rep rep;
842 	int fptype;
843 	char *fp, *ra, **comments = NULL;
844 
845 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
846 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
847 
848 	pkcs11_init(1);
849 	nkeys = pkcs11_add_provider(pkcs11provider, NULL, &keys, &comments);
850 	if (nkeys <= 0)
851 		fatal("cannot read public key from pkcs11");
852 	for (i = 0; i < nkeys; i++) {
853 		if (print_fingerprint) {
854 			fp = sshkey_fingerprint(keys[i], fptype, rep);
855 			ra = sshkey_fingerprint(keys[i], fingerprint_hash,
856 			    SSH_FP_RANDOMART);
857 			if (fp == NULL || ra == NULL)
858 				fatal_f("sshkey_fingerprint fail");
859 			printf("%u %s %s (PKCS11 key)\n", sshkey_size(keys[i]),
860 			    fp, sshkey_type(keys[i]));
861 			if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
862 				printf("%s\n", ra);
863 			free(ra);
864 			free(fp);
865 		} else {
866 			(void) sshkey_write(keys[i], stdout); /* XXX check */
867 			fprintf(stdout, "%s%s\n",
868 			    *(comments[i]) == '\0' ? "" : " ", comments[i]);
869 		}
870 		free(comments[i]);
871 		sshkey_free(keys[i]);
872 	}
873 	free(comments);
874 	free(keys);
875 	pkcs11_terminate();
876 	exit(0);
877 #else
878 	fatal("no pkcs11 support");
879 #endif /* ENABLE_PKCS11 */
880 }
881 
882 static struct sshkey *
883 try_read_key(char **cpp)
884 {
885 	struct sshkey *ret;
886 	int r;
887 
888 	if ((ret = sshkey_new(KEY_UNSPEC)) == NULL)
889 		fatal("sshkey_new failed");
890 	if ((r = sshkey_read(ret, cpp)) == 0)
891 		return ret;
892 	/* Not a key */
893 	sshkey_free(ret);
894 	return NULL;
895 }
896 
897 static void
898 fingerprint_one_key(const struct sshkey *public, const char *comment)
899 {
900 	char *fp = NULL, *ra = NULL;
901 	enum sshkey_fp_rep rep;
902 	int fptype;
903 
904 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
905 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
906 	fp = sshkey_fingerprint(public, fptype, rep);
907 	ra = sshkey_fingerprint(public, fingerprint_hash, SSH_FP_RANDOMART);
908 	if (fp == NULL || ra == NULL)
909 		fatal_f("sshkey_fingerprint failed");
910 	mprintf("%u %s %s (%s)\n", sshkey_size(public), fp,
911 	    comment ? comment : "no comment", sshkey_type(public));
912 	if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
913 		printf("%s\n", ra);
914 	free(ra);
915 	free(fp);
916 }
917 
918 static void
919 fingerprint_private(const char *path)
920 {
921 	struct stat st;
922 	char *comment = NULL;
923 	struct sshkey *privkey = NULL, *pubkey = NULL;
924 	int r;
925 
926 	if (stat(identity_file, &st) == -1)
927 		fatal("%s: %s", path, strerror(errno));
928 	if ((r = sshkey_load_public(path, &pubkey, &comment)) != 0)
929 		debug_r(r, "load public \"%s\"", path);
930 	if (pubkey == NULL || comment == NULL || *comment == '\0') {
931 		free(comment);
932 		if ((r = sshkey_load_private(path, NULL,
933 		    &privkey, &comment)) != 0)
934 			debug_r(r, "load private \"%s\"", path);
935 	}
936 	if (pubkey == NULL && privkey == NULL)
937 		fatal("%s is not a key file.", path);
938 
939 	fingerprint_one_key(pubkey == NULL ? privkey : pubkey, comment);
940 	sshkey_free(pubkey);
941 	sshkey_free(privkey);
942 	free(comment);
943 }
944 
945 static void
946 do_fingerprint(struct passwd *pw)
947 {
948 	FILE *f;
949 	struct sshkey *public = NULL;
950 	char *comment = NULL, *cp, *ep, *line = NULL;
951 	size_t linesize = 0;
952 	int i, invalid = 1;
953 	const char *path;
954 	u_long lnum = 0;
955 
956 	if (!have_identity)
957 		ask_filename(pw, "Enter file in which the key is");
958 	path = identity_file;
959 
960 	if (strcmp(identity_file, "-") == 0) {
961 		f = stdin;
962 		path = "(stdin)";
963 	} else if ((f = fopen(path, "r")) == NULL)
964 		fatal("%s: %s: %s", __progname, path, strerror(errno));
965 
966 	while (getline(&line, &linesize, f) != -1) {
967 		lnum++;
968 		cp = line;
969 		cp[strcspn(cp, "\n")] = '\0';
970 		/* Trim leading space and comments */
971 		cp = line + strspn(line, " \t");
972 		if (*cp == '#' || *cp == '\0')
973 			continue;
974 
975 		/*
976 		 * Input may be plain keys, private keys, authorized_keys
977 		 * or known_hosts.
978 		 */
979 
980 		/*
981 		 * Try private keys first. Assume a key is private if
982 		 * "SSH PRIVATE KEY" appears on the first line and we're
983 		 * not reading from stdin (XXX support private keys on stdin).
984 		 */
985 		if (lnum == 1 && strcmp(identity_file, "-") != 0 &&
986 		    strstr(cp, "PRIVATE KEY") != NULL) {
987 			free(line);
988 			fclose(f);
989 			fingerprint_private(path);
990 			exit(0);
991 		}
992 
993 		/*
994 		 * If it's not a private key, then this must be prepared to
995 		 * accept a public key prefixed with a hostname or options.
996 		 * Try a bare key first, otherwise skip the leading stuff.
997 		 */
998 		if ((public = try_read_key(&cp)) == NULL) {
999 			i = strtol(cp, &ep, 10);
1000 			if (i == 0 || ep == NULL ||
1001 			    (*ep != ' ' && *ep != '\t')) {
1002 				int quoted = 0;
1003 
1004 				comment = cp;
1005 				for (; *cp && (quoted || (*cp != ' ' &&
1006 				    *cp != '\t')); cp++) {
1007 					if (*cp == '\\' && cp[1] == '"')
1008 						cp++;	/* Skip both */
1009 					else if (*cp == '"')
1010 						quoted = !quoted;
1011 				}
1012 				if (!*cp)
1013 					continue;
1014 				*cp++ = '\0';
1015 			}
1016 		}
1017 		/* Retry after parsing leading hostname/key options */
1018 		if (public == NULL && (public = try_read_key(&cp)) == NULL) {
1019 			debug("%s:%lu: not a public key", path, lnum);
1020 			continue;
1021 		}
1022 
1023 		/* Find trailing comment, if any */
1024 		for (; *cp == ' ' || *cp == '\t'; cp++)
1025 			;
1026 		if (*cp != '\0' && *cp != '#')
1027 			comment = cp;
1028 
1029 		fingerprint_one_key(public, comment);
1030 		sshkey_free(public);
1031 		invalid = 0; /* One good key in the file is sufficient */
1032 	}
1033 	fclose(f);
1034 	free(line);
1035 
1036 	if (invalid)
1037 		fatal("%s is not a public key file.", path);
1038 	exit(0);
1039 }
1040 
1041 static void
1042 do_gen_all_hostkeys(struct passwd *pw)
1043 {
1044 	struct {
1045 		char *key_type;
1046 		char *key_type_display;
1047 		char *path;
1048 	} key_types[] = {
1049 #ifdef WITH_OPENSSL
1050 		{ "rsa", "RSA" ,_PATH_HOST_RSA_KEY_FILE },
1051 #ifdef OPENSSL_HAS_ECC
1052 		{ "ecdsa", "ECDSA",_PATH_HOST_ECDSA_KEY_FILE },
1053 #endif /* OPENSSL_HAS_ECC */
1054 #endif /* WITH_OPENSSL */
1055 		{ "ed25519", "ED25519",_PATH_HOST_ED25519_KEY_FILE },
1056 #ifdef WITH_XMSS
1057 		{ "xmss", "XMSS",_PATH_HOST_XMSS_KEY_FILE },
1058 #endif /* WITH_XMSS */
1059 		{ NULL, NULL, NULL }
1060 	};
1061 
1062 	u_int32_t bits = 0;
1063 	int first = 0;
1064 	struct stat st;
1065 	struct sshkey *private, *public;
1066 	char comment[1024], *prv_tmp, *pub_tmp, *prv_file, *pub_file;
1067 	int i, type, fd, r;
1068 
1069 	for (i = 0; key_types[i].key_type; i++) {
1070 		public = private = NULL;
1071 		prv_tmp = pub_tmp = prv_file = pub_file = NULL;
1072 
1073 		xasprintf(&prv_file, "%s%s",
1074 		    identity_file, key_types[i].path);
1075 
1076 		/* Check whether private key exists and is not zero-length */
1077 		if (stat(prv_file, &st) == 0) {
1078 			if (st.st_size != 0)
1079 				goto next;
1080 		} else if (errno != ENOENT) {
1081 			error("Could not stat %s: %s", key_types[i].path,
1082 			    strerror(errno));
1083 			goto failnext;
1084 		}
1085 
1086 		/*
1087 		 * Private key doesn't exist or is invalid; proceed with
1088 		 * key generation.
1089 		 */
1090 		xasprintf(&prv_tmp, "%s%s.XXXXXXXXXX",
1091 		    identity_file, key_types[i].path);
1092 		xasprintf(&pub_tmp, "%s%s.pub.XXXXXXXXXX",
1093 		    identity_file, key_types[i].path);
1094 		xasprintf(&pub_file, "%s%s.pub",
1095 		    identity_file, key_types[i].path);
1096 
1097 		if (first == 0) {
1098 			first = 1;
1099 			printf("%s: generating new host keys: ", __progname);
1100 		}
1101 		printf("%s ", key_types[i].key_type_display);
1102 		fflush(stdout);
1103 		type = sshkey_type_from_name(key_types[i].key_type);
1104 		if ((fd = mkstemp(prv_tmp)) == -1) {
1105 			error("Could not save your private key in %s: %s",
1106 			    prv_tmp, strerror(errno));
1107 			goto failnext;
1108 		}
1109 		(void)close(fd); /* just using mkstemp() to reserve a name */
1110 		bits = 0;
1111 		type_bits_valid(type, NULL, &bits);
1112 		if ((r = sshkey_generate(type, bits, &private)) != 0) {
1113 			error_r(r, "sshkey_generate failed");
1114 			goto failnext;
1115 		}
1116 		if ((r = sshkey_from_private(private, &public)) != 0)
1117 			fatal_fr(r, "sshkey_from_private");
1118 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name,
1119 		    hostname);
1120 		if ((r = sshkey_save_private(private, prv_tmp, "",
1121 		    comment, private_key_format, openssh_format_cipher,
1122 		    rounds)) != 0) {
1123 			error_r(r, "Saving key \"%s\" failed", prv_tmp);
1124 			goto failnext;
1125 		}
1126 		if ((fd = mkstemp(pub_tmp)) == -1) {
1127 			error("Could not save your public key in %s: %s",
1128 			    pub_tmp, strerror(errno));
1129 			goto failnext;
1130 		}
1131 		(void)fchmod(fd, 0644);
1132 		(void)close(fd);
1133 		if ((r = sshkey_save_public(public, pub_tmp, comment)) != 0) {
1134 			error_r(r, "Unable to save public key to %s",
1135 			    identity_file);
1136 			goto failnext;
1137 		}
1138 
1139 		/* Rename temporary files to their permanent locations. */
1140 		if (rename(pub_tmp, pub_file) != 0) {
1141 			error("Unable to move %s into position: %s",
1142 			    pub_file, strerror(errno));
1143 			goto failnext;
1144 		}
1145 		if (rename(prv_tmp, prv_file) != 0) {
1146 			error("Unable to move %s into position: %s",
1147 			    key_types[i].path, strerror(errno));
1148  failnext:
1149 			first = 0;
1150 			goto next;
1151 		}
1152  next:
1153 		sshkey_free(private);
1154 		sshkey_free(public);
1155 		free(prv_tmp);
1156 		free(pub_tmp);
1157 		free(prv_file);
1158 		free(pub_file);
1159 	}
1160 	if (first != 0)
1161 		printf("\n");
1162 }
1163 
1164 struct known_hosts_ctx {
1165 	const char *host;	/* Hostname searched for in find/delete case */
1166 	FILE *out;		/* Output file, stdout for find_hosts case */
1167 	int has_unhashed;	/* When hashing, original had unhashed hosts */
1168 	int found_key;		/* For find/delete, host was found */
1169 	int invalid;		/* File contained invalid items; don't delete */
1170 	int hash_hosts;		/* Hash hostnames as we go */
1171 	int find_host;		/* Search for specific hostname */
1172 	int delete_host;	/* Delete host from known_hosts */
1173 };
1174 
1175 static int
1176 known_hosts_hash(struct hostkey_foreach_line *l, void *_ctx)
1177 {
1178 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1179 	char *hashed, *cp, *hosts, *ohosts;
1180 	int has_wild = l->hosts && strcspn(l->hosts, "*?!") != strlen(l->hosts);
1181 	int was_hashed = l->hosts && l->hosts[0] == HASH_DELIM;
1182 
1183 	switch (l->status) {
1184 	case HKF_STATUS_OK:
1185 	case HKF_STATUS_MATCHED:
1186 		/*
1187 		 * Don't hash hosts already already hashed, with wildcard
1188 		 * characters or a CA/revocation marker.
1189 		 */
1190 		if (was_hashed || has_wild || l->marker != MRK_NONE) {
1191 			fprintf(ctx->out, "%s\n", l->line);
1192 			if (has_wild && !ctx->find_host) {
1193 				logit("%s:%lu: ignoring host name "
1194 				    "with wildcard: %.64s", l->path,
1195 				    l->linenum, l->hosts);
1196 			}
1197 			return 0;
1198 		}
1199 		/*
1200 		 * Split any comma-separated hostnames from the host list,
1201 		 * hash and store separately.
1202 		 */
1203 		ohosts = hosts = xstrdup(l->hosts);
1204 		while ((cp = strsep(&hosts, ",")) != NULL && *cp != '\0') {
1205 			lowercase(cp);
1206 			if ((hashed = host_hash(cp, NULL, 0)) == NULL)
1207 				fatal("hash_host failed");
1208 			fprintf(ctx->out, "%s %s\n", hashed, l->rawkey);
1209 			free(hashed);
1210 			ctx->has_unhashed = 1;
1211 		}
1212 		free(ohosts);
1213 		return 0;
1214 	case HKF_STATUS_INVALID:
1215 		/* Retain invalid lines, but mark file as invalid. */
1216 		ctx->invalid = 1;
1217 		logit("%s:%lu: invalid line", l->path, l->linenum);
1218 		/* FALLTHROUGH */
1219 	default:
1220 		fprintf(ctx->out, "%s\n", l->line);
1221 		return 0;
1222 	}
1223 	/* NOTREACHED */
1224 	return -1;
1225 }
1226 
1227 static int
1228 known_hosts_find_delete(struct hostkey_foreach_line *l, void *_ctx)
1229 {
1230 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1231 	enum sshkey_fp_rep rep;
1232 	int fptype;
1233 	char *fp = NULL, *ra = NULL;
1234 
1235 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
1236 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
1237 
1238 	if (l->status == HKF_STATUS_MATCHED) {
1239 		if (ctx->delete_host) {
1240 			if (l->marker != MRK_NONE) {
1241 				/* Don't remove CA and revocation lines */
1242 				fprintf(ctx->out, "%s\n", l->line);
1243 			} else {
1244 				/*
1245 				 * Hostname matches and has no CA/revoke
1246 				 * marker, delete it by *not* writing the
1247 				 * line to ctx->out.
1248 				 */
1249 				ctx->found_key = 1;
1250 				if (!quiet)
1251 					printf("# Host %s found: line %lu\n",
1252 					    ctx->host, l->linenum);
1253 			}
1254 			return 0;
1255 		} else if (ctx->find_host) {
1256 			ctx->found_key = 1;
1257 			if (!quiet) {
1258 				printf("# Host %s found: line %lu %s\n",
1259 				    ctx->host,
1260 				    l->linenum, l->marker == MRK_CA ? "CA" :
1261 				    (l->marker == MRK_REVOKE ? "REVOKED" : ""));
1262 			}
1263 			if (ctx->hash_hosts)
1264 				known_hosts_hash(l, ctx);
1265 			else if (print_fingerprint) {
1266 				fp = sshkey_fingerprint(l->key, fptype, rep);
1267 				ra = sshkey_fingerprint(l->key,
1268 				    fingerprint_hash, SSH_FP_RANDOMART);
1269 				if (fp == NULL || ra == NULL)
1270 					fatal_f("sshkey_fingerprint failed");
1271 				mprintf("%s %s %s%s%s\n", ctx->host,
1272 				    sshkey_type(l->key), fp,
1273 				    l->comment[0] ? " " : "",
1274 				    l->comment);
1275 				if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
1276 					printf("%s\n", ra);
1277 				free(ra);
1278 				free(fp);
1279 			} else
1280 				fprintf(ctx->out, "%s\n", l->line);
1281 			return 0;
1282 		}
1283 	} else if (ctx->delete_host) {
1284 		/* Retain non-matching hosts when deleting */
1285 		if (l->status == HKF_STATUS_INVALID) {
1286 			ctx->invalid = 1;
1287 			logit("%s:%lu: invalid line", l->path, l->linenum);
1288 		}
1289 		fprintf(ctx->out, "%s\n", l->line);
1290 	}
1291 	return 0;
1292 }
1293 
1294 static void
1295 do_known_hosts(struct passwd *pw, const char *name, int find_host,
1296     int delete_host, int hash_hosts)
1297 {
1298 	char *cp, tmp[PATH_MAX], old[PATH_MAX];
1299 	int r, fd, oerrno, inplace = 0;
1300 	struct known_hosts_ctx ctx;
1301 	u_int foreach_options;
1302 	struct stat sb;
1303 
1304 	if (!have_identity) {
1305 		cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
1306 		if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
1307 		    sizeof(identity_file))
1308 			fatal("Specified known hosts path too long");
1309 		free(cp);
1310 		have_identity = 1;
1311 	}
1312 	if (stat(identity_file, &sb) != 0)
1313 		fatal("Cannot stat %s: %s", identity_file, strerror(errno));
1314 
1315 	memset(&ctx, 0, sizeof(ctx));
1316 	ctx.out = stdout;
1317 	ctx.host = name;
1318 	ctx.hash_hosts = hash_hosts;
1319 	ctx.find_host = find_host;
1320 	ctx.delete_host = delete_host;
1321 
1322 	/*
1323 	 * Find hosts goes to stdout, hash and deletions happen in-place
1324 	 * A corner case is ssh-keygen -HF foo, which should go to stdout
1325 	 */
1326 	if (!find_host && (hash_hosts || delete_host)) {
1327 		if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
1328 		    strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
1329 		    strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
1330 		    strlcat(old, ".old", sizeof(old)) >= sizeof(old))
1331 			fatal("known_hosts path too long");
1332 		umask(077);
1333 		if ((fd = mkstemp(tmp)) == -1)
1334 			fatal("mkstemp: %s", strerror(errno));
1335 		if ((ctx.out = fdopen(fd, "w")) == NULL) {
1336 			oerrno = errno;
1337 			unlink(tmp);
1338 			fatal("fdopen: %s", strerror(oerrno));
1339 		}
1340 		fchmod(fd, sb.st_mode & 0644);
1341 		inplace = 1;
1342 	}
1343 	/* XXX support identity_file == "-" for stdin */
1344 	foreach_options = find_host ? HKF_WANT_MATCH : 0;
1345 	foreach_options |= print_fingerprint ? HKF_WANT_PARSE_KEY : 0;
1346 	if ((r = hostkeys_foreach(identity_file, (find_host || !hash_hosts) ?
1347 	    known_hosts_find_delete : known_hosts_hash, &ctx, name, NULL,
1348 	    foreach_options, 0)) != 0) {
1349 		if (inplace)
1350 			unlink(tmp);
1351 		fatal_fr(r, "hostkeys_foreach");
1352 	}
1353 
1354 	if (inplace)
1355 		fclose(ctx.out);
1356 
1357 	if (ctx.invalid) {
1358 		error("%s is not a valid known_hosts file.", identity_file);
1359 		if (inplace) {
1360 			error("Not replacing existing known_hosts "
1361 			    "file because of errors");
1362 			unlink(tmp);
1363 		}
1364 		exit(1);
1365 	} else if (delete_host && !ctx.found_key) {
1366 		logit("Host %s not found in %s", name, identity_file);
1367 		if (inplace)
1368 			unlink(tmp);
1369 	} else if (inplace) {
1370 		/* Backup existing file */
1371 		if (unlink(old) == -1 && errno != ENOENT)
1372 			fatal("unlink %.100s: %s", old, strerror(errno));
1373 		if (link(identity_file, old) == -1)
1374 			fatal("link %.100s to %.100s: %s", identity_file, old,
1375 			    strerror(errno));
1376 		/* Move new one into place */
1377 		if (rename(tmp, identity_file) == -1) {
1378 			error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
1379 			    strerror(errno));
1380 			unlink(tmp);
1381 			unlink(old);
1382 			exit(1);
1383 		}
1384 
1385 		printf("%s updated.\n", identity_file);
1386 		printf("Original contents retained as %s\n", old);
1387 		if (ctx.has_unhashed) {
1388 			logit("WARNING: %s contains unhashed entries", old);
1389 			logit("Delete this file to ensure privacy "
1390 			    "of hostnames");
1391 		}
1392 	}
1393 
1394 	exit (find_host && !ctx.found_key);
1395 }
1396 
1397 /*
1398  * Perform changing a passphrase.  The argument is the passwd structure
1399  * for the current user.
1400  */
1401 static void
1402 do_change_passphrase(struct passwd *pw)
1403 {
1404 	char *comment;
1405 	char *old_passphrase, *passphrase1, *passphrase2;
1406 	struct stat st;
1407 	struct sshkey *private;
1408 	int r;
1409 
1410 	if (!have_identity)
1411 		ask_filename(pw, "Enter file in which the key is");
1412 	if (stat(identity_file, &st) == -1)
1413 		fatal("%s: %s", identity_file, strerror(errno));
1414 	/* Try to load the file with empty passphrase. */
1415 	r = sshkey_load_private(identity_file, "", &private, &comment);
1416 	if (r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1417 		if (identity_passphrase)
1418 			old_passphrase = xstrdup(identity_passphrase);
1419 		else
1420 			old_passphrase =
1421 			    read_passphrase("Enter old passphrase: ",
1422 			    RP_ALLOW_STDIN);
1423 		r = sshkey_load_private(identity_file, old_passphrase,
1424 		    &private, &comment);
1425 		freezero(old_passphrase, strlen(old_passphrase));
1426 		if (r != 0)
1427 			goto badkey;
1428 	} else if (r != 0) {
1429  badkey:
1430 		fatal_r(r, "Failed to load key %s", identity_file);
1431 	}
1432 	if (comment)
1433 		mprintf("Key has comment '%s'\n", comment);
1434 
1435 	/* Ask the new passphrase (twice). */
1436 	if (identity_new_passphrase) {
1437 		passphrase1 = xstrdup(identity_new_passphrase);
1438 		passphrase2 = NULL;
1439 	} else {
1440 		passphrase1 =
1441 			read_passphrase("Enter new passphrase (empty for no "
1442 			    "passphrase): ", RP_ALLOW_STDIN);
1443 		passphrase2 = read_passphrase("Enter same passphrase again: ",
1444 		    RP_ALLOW_STDIN);
1445 
1446 		/* Verify that they are the same. */
1447 		if (strcmp(passphrase1, passphrase2) != 0) {
1448 			explicit_bzero(passphrase1, strlen(passphrase1));
1449 			explicit_bzero(passphrase2, strlen(passphrase2));
1450 			free(passphrase1);
1451 			free(passphrase2);
1452 			printf("Pass phrases do not match.  Try again.\n");
1453 			exit(1);
1454 		}
1455 		/* Destroy the other copy. */
1456 		freezero(passphrase2, strlen(passphrase2));
1457 	}
1458 
1459 	/* Save the file using the new passphrase. */
1460 	if ((r = sshkey_save_private(private, identity_file, passphrase1,
1461 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
1462 		error_r(r, "Saving key \"%s\" failed", identity_file);
1463 		freezero(passphrase1, strlen(passphrase1));
1464 		sshkey_free(private);
1465 		free(comment);
1466 		exit(1);
1467 	}
1468 	/* Destroy the passphrase and the copy of the key in memory. */
1469 	freezero(passphrase1, strlen(passphrase1));
1470 	sshkey_free(private);		 /* Destroys contents */
1471 	free(comment);
1472 
1473 	printf("Your identification has been saved with the new passphrase.\n");
1474 	exit(0);
1475 }
1476 
1477 /*
1478  * Print the SSHFP RR.
1479  */
1480 static int
1481 do_print_resource_record(struct passwd *pw, char *fname, char *hname,
1482     int print_generic)
1483 {
1484 	struct sshkey *public;
1485 	char *comment = NULL;
1486 	struct stat st;
1487 	int r;
1488 
1489 	if (fname == NULL)
1490 		fatal_f("no filename");
1491 	if (stat(fname, &st) == -1) {
1492 		if (errno == ENOENT)
1493 			return 0;
1494 		fatal("%s: %s", fname, strerror(errno));
1495 	}
1496 	if ((r = sshkey_load_public(fname, &public, &comment)) != 0)
1497 		fatal_r(r, "Failed to read v2 public key from \"%s\"", fname);
1498 	export_dns_rr(hname, public, stdout, print_generic);
1499 	sshkey_free(public);
1500 	free(comment);
1501 	return 1;
1502 }
1503 
1504 /*
1505  * Change the comment of a private key file.
1506  */
1507 static void
1508 do_change_comment(struct passwd *pw, const char *identity_comment)
1509 {
1510 	char new_comment[1024], *comment, *passphrase;
1511 	struct sshkey *private;
1512 	struct sshkey *public;
1513 	struct stat st;
1514 	int r;
1515 
1516 	if (!have_identity)
1517 		ask_filename(pw, "Enter file in which the key is");
1518 	if (stat(identity_file, &st) == -1)
1519 		fatal("%s: %s", identity_file, strerror(errno));
1520 	if ((r = sshkey_load_private(identity_file, "",
1521 	    &private, &comment)) == 0)
1522 		passphrase = xstrdup("");
1523 	else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
1524 		fatal_r(r, "Cannot load private key \"%s\"", identity_file);
1525 	else {
1526 		if (identity_passphrase)
1527 			passphrase = xstrdup(identity_passphrase);
1528 		else if (identity_new_passphrase)
1529 			passphrase = xstrdup(identity_new_passphrase);
1530 		else
1531 			passphrase = read_passphrase("Enter passphrase: ",
1532 			    RP_ALLOW_STDIN);
1533 		/* Try to load using the passphrase. */
1534 		if ((r = sshkey_load_private(identity_file, passphrase,
1535 		    &private, &comment)) != 0) {
1536 			freezero(passphrase, strlen(passphrase));
1537 			fatal_r(r, "Cannot load private key \"%s\"",
1538 			    identity_file);
1539 		}
1540 	}
1541 
1542 	if (private->type != KEY_ED25519 && private->type != KEY_XMSS &&
1543 	    private_key_format != SSHKEY_PRIVATE_OPENSSH) {
1544 		error("Comments are only supported for keys stored in "
1545 		    "the new format (-o).");
1546 		explicit_bzero(passphrase, strlen(passphrase));
1547 		sshkey_free(private);
1548 		exit(1);
1549 	}
1550 	if (comment)
1551 		printf("Old comment: %s\n", comment);
1552 	else
1553 		printf("No existing comment\n");
1554 
1555 	if (identity_comment) {
1556 		strlcpy(new_comment, identity_comment, sizeof(new_comment));
1557 	} else {
1558 		printf("New comment: ");
1559 		fflush(stdout);
1560 		if (!fgets(new_comment, sizeof(new_comment), stdin)) {
1561 			explicit_bzero(passphrase, strlen(passphrase));
1562 			sshkey_free(private);
1563 			exit(1);
1564 		}
1565 		new_comment[strcspn(new_comment, "\n")] = '\0';
1566 	}
1567 	if (comment != NULL && strcmp(comment, new_comment) == 0) {
1568 		printf("No change to comment\n");
1569 		free(passphrase);
1570 		sshkey_free(private);
1571 		free(comment);
1572 		exit(0);
1573 	}
1574 
1575 	/* Save the file using the new passphrase. */
1576 	if ((r = sshkey_save_private(private, identity_file, passphrase,
1577 	    new_comment, private_key_format, openssh_format_cipher,
1578 	    rounds)) != 0) {
1579 		error_r(r, "Saving key \"%s\" failed", identity_file);
1580 		freezero(passphrase, strlen(passphrase));
1581 		sshkey_free(private);
1582 		free(comment);
1583 		exit(1);
1584 	}
1585 	freezero(passphrase, strlen(passphrase));
1586 	if ((r = sshkey_from_private(private, &public)) != 0)
1587 		fatal_fr(r, "sshkey_from_private");
1588 	sshkey_free(private);
1589 
1590 	strlcat(identity_file, ".pub", sizeof(identity_file));
1591 	if ((r = sshkey_save_public(public, identity_file, new_comment)) != 0)
1592 		fatal_r(r, "Unable to save public key to %s", identity_file);
1593 	sshkey_free(public);
1594 	free(comment);
1595 
1596 	if (strlen(new_comment) > 0)
1597 		printf("Comment '%s' applied\n", new_comment);
1598 	else
1599 		printf("Comment removed\n");
1600 
1601 	exit(0);
1602 }
1603 
1604 static void
1605 cert_ext_add(const char *key, const char *value, int iscrit)
1606 {
1607 	cert_ext = xreallocarray(cert_ext, ncert_ext + 1, sizeof(*cert_ext));
1608 	cert_ext[ncert_ext].key = xstrdup(key);
1609 	cert_ext[ncert_ext].val = value == NULL ? NULL : xstrdup(value);
1610 	cert_ext[ncert_ext].crit = iscrit;
1611 	ncert_ext++;
1612 }
1613 
1614 /* qsort(3) comparison function for certificate extensions */
1615 static int
1616 cert_ext_cmp(const void *_a, const void *_b)
1617 {
1618 	const struct cert_ext *a = (const struct cert_ext *)_a;
1619 	const struct cert_ext *b = (const struct cert_ext *)_b;
1620 	int r;
1621 
1622 	if (a->crit != b->crit)
1623 		return (a->crit < b->crit) ? -1 : 1;
1624 	if ((r = strcmp(a->key, b->key)) != 0)
1625 		return r;
1626 	if ((a->val == NULL) != (b->val == NULL))
1627 		return (a->val == NULL) ? -1 : 1;
1628 	if (a->val != NULL && (r = strcmp(a->val, b->val)) != 0)
1629 		return r;
1630 	return 0;
1631 }
1632 
1633 #define OPTIONS_CRITICAL	1
1634 #define OPTIONS_EXTENSIONS	2
1635 static void
1636 prepare_options_buf(struct sshbuf *c, int which)
1637 {
1638 	struct sshbuf *b;
1639 	size_t i;
1640 	int r;
1641 	const struct cert_ext *ext;
1642 
1643 	if ((b = sshbuf_new()) == NULL)
1644 		fatal_f("sshbuf_new failed");
1645 	sshbuf_reset(c);
1646 	for (i = 0; i < ncert_ext; i++) {
1647 		ext = &cert_ext[i];
1648 		if ((ext->crit && (which & OPTIONS_EXTENSIONS)) ||
1649 		    (!ext->crit && (which & OPTIONS_CRITICAL)))
1650 			continue;
1651 		if (ext->val == NULL) {
1652 			/* flag option */
1653 			debug3_f("%s", ext->key);
1654 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1655 			    (r = sshbuf_put_string(c, NULL, 0)) != 0)
1656 				fatal_fr(r, "prepare flag");
1657 		} else {
1658 			/* key/value option */
1659 			debug3_f("%s=%s", ext->key, ext->val);
1660 			sshbuf_reset(b);
1661 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1662 			    (r = sshbuf_put_cstring(b, ext->val)) != 0 ||
1663 			    (r = sshbuf_put_stringb(c, b)) != 0)
1664 				fatal_fr(r, "prepare k/v");
1665 		}
1666 	}
1667 	sshbuf_free(b);
1668 }
1669 
1670 static void
1671 finalise_cert_exts(void)
1672 {
1673 	/* critical options */
1674 	if (certflags_command != NULL)
1675 		cert_ext_add("force-command", certflags_command, 1);
1676 	if (certflags_src_addr != NULL)
1677 		cert_ext_add("source-address", certflags_src_addr, 1);
1678 	if ((certflags_flags & CERTOPT_REQUIRE_VERIFY) != 0)
1679 		cert_ext_add("verify-required", NULL, 1);
1680 	/* extensions */
1681 	if ((certflags_flags & CERTOPT_X_FWD) != 0)
1682 		cert_ext_add("permit-X11-forwarding", NULL, 0);
1683 	if ((certflags_flags & CERTOPT_AGENT_FWD) != 0)
1684 		cert_ext_add("permit-agent-forwarding", NULL, 0);
1685 	if ((certflags_flags & CERTOPT_PORT_FWD) != 0)
1686 		cert_ext_add("permit-port-forwarding", NULL, 0);
1687 	if ((certflags_flags & CERTOPT_PTY) != 0)
1688 		cert_ext_add("permit-pty", NULL, 0);
1689 	if ((certflags_flags & CERTOPT_USER_RC) != 0)
1690 		cert_ext_add("permit-user-rc", NULL, 0);
1691 	if ((certflags_flags & CERTOPT_NO_REQUIRE_USER_PRESENCE) != 0)
1692 		cert_ext_add("no-touch-required", NULL, 0);
1693 	/* order lexically by key */
1694 	if (ncert_ext > 0)
1695 		qsort(cert_ext, ncert_ext, sizeof(*cert_ext), cert_ext_cmp);
1696 }
1697 
1698 static struct sshkey *
1699 load_pkcs11_key(char *path)
1700 {
1701 #ifdef ENABLE_PKCS11
1702 	struct sshkey **keys = NULL, *public, *private = NULL;
1703 	int r, i, nkeys;
1704 
1705 	if ((r = sshkey_load_public(path, &public, NULL)) != 0)
1706 		fatal_r(r, "Couldn't load CA public key \"%s\"", path);
1707 
1708 	nkeys = pkcs11_add_provider(pkcs11provider, identity_passphrase,
1709 	    &keys, NULL);
1710 	debug3_f("%d keys", nkeys);
1711 	if (nkeys <= 0)
1712 		fatal("cannot read public key from pkcs11");
1713 	for (i = 0; i < nkeys; i++) {
1714 		if (sshkey_equal_public(public, keys[i])) {
1715 			private = keys[i];
1716 			continue;
1717 		}
1718 		sshkey_free(keys[i]);
1719 	}
1720 	free(keys);
1721 	sshkey_free(public);
1722 	return private;
1723 #else
1724 	fatal("no pkcs11 support");
1725 #endif /* ENABLE_PKCS11 */
1726 }
1727 
1728 /* Signer for sshkey_certify_custom that uses the agent */
1729 static int
1730 agent_signer(struct sshkey *key, u_char **sigp, size_t *lenp,
1731     const u_char *data, size_t datalen,
1732     const char *alg, const char *provider, const char *pin,
1733     u_int compat, void *ctx)
1734 {
1735 	int *agent_fdp = (int *)ctx;
1736 
1737 	return ssh_agent_sign(*agent_fdp, key, sigp, lenp,
1738 	    data, datalen, alg, compat);
1739 }
1740 
1741 static void
1742 do_ca_sign(struct passwd *pw, const char *ca_key_path, int prefer_agent,
1743     unsigned long long cert_serial, int cert_serial_autoinc,
1744     int argc, char **argv)
1745 {
1746 	int r, i, found, agent_fd = -1;
1747 	u_int n;
1748 	struct sshkey *ca, *public;
1749 	char valid[64], *otmp, *tmp, *cp, *out, *comment;
1750 	char *ca_fp = NULL, **plist = NULL, *pin = NULL;
1751 	struct ssh_identitylist *agent_ids;
1752 	size_t j;
1753 	struct notifier_ctx *notifier = NULL;
1754 
1755 #ifdef ENABLE_PKCS11
1756 	pkcs11_init(1);
1757 #endif
1758 	tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
1759 	if (pkcs11provider != NULL) {
1760 		/* If a PKCS#11 token was specified then try to use it */
1761 		if ((ca = load_pkcs11_key(tmp)) == NULL)
1762 			fatal("No PKCS#11 key matching %s found", ca_key_path);
1763 	} else if (prefer_agent) {
1764 		/*
1765 		 * Agent signature requested. Try to use agent after making
1766 		 * sure the public key specified is actually present in the
1767 		 * agent.
1768 		 */
1769 		if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
1770 			fatal_r(r, "Cannot load CA public key %s", tmp);
1771 		if ((r = ssh_get_authentication_socket(&agent_fd)) != 0)
1772 			fatal_r(r, "Cannot use public key for CA signature");
1773 		if ((r = ssh_fetch_identitylist(agent_fd, &agent_ids)) != 0)
1774 			fatal_r(r, "Retrieve agent key list");
1775 		found = 0;
1776 		for (j = 0; j < agent_ids->nkeys; j++) {
1777 			if (sshkey_equal(ca, agent_ids->keys[j])) {
1778 				found = 1;
1779 				break;
1780 			}
1781 		}
1782 		if (!found)
1783 			fatal("CA key %s not found in agent", tmp);
1784 		ssh_free_identitylist(agent_ids);
1785 		ca->flags |= SSHKEY_FLAG_EXT;
1786 	} else {
1787 		/* CA key is assumed to be a private key on the filesystem */
1788 		ca = load_identity(tmp, NULL);
1789 		if (sshkey_is_sk(ca) &&
1790 		    (ca->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
1791 			if ((pin = read_passphrase("Enter PIN for CA key: ",
1792 			    RP_ALLOW_STDIN)) == NULL)
1793 				fatal_f("couldn't read PIN");
1794 		}
1795 	}
1796 	free(tmp);
1797 
1798 	if (key_type_name != NULL) {
1799 		if (sshkey_type_from_name(key_type_name) != ca->type) {
1800 			fatal("CA key type %s doesn't match specified %s",
1801 			    sshkey_ssh_name(ca), key_type_name);
1802 		}
1803 	} else if (ca->type == KEY_RSA) {
1804 		/* Default to a good signature algorithm */
1805 		key_type_name = "rsa-sha2-512";
1806 	}
1807 	ca_fp = sshkey_fingerprint(ca, fingerprint_hash, SSH_FP_DEFAULT);
1808 
1809 	finalise_cert_exts();
1810 	for (i = 0; i < argc; i++) {
1811 		/* Split list of principals */
1812 		n = 0;
1813 		if (cert_principals != NULL) {
1814 			otmp = tmp = xstrdup(cert_principals);
1815 			plist = NULL;
1816 			for (; (cp = strsep(&tmp, ",")) != NULL; n++) {
1817 				plist = xreallocarray(plist, n + 1, sizeof(*plist));
1818 				if (*(plist[n] = xstrdup(cp)) == '\0')
1819 					fatal("Empty principal name");
1820 			}
1821 			free(otmp);
1822 		}
1823 		if (n > SSHKEY_CERT_MAX_PRINCIPALS)
1824 			fatal("Too many certificate principals specified");
1825 
1826 		tmp = tilde_expand_filename(argv[i], pw->pw_uid);
1827 		if ((r = sshkey_load_public(tmp, &public, &comment)) != 0)
1828 			fatal_r(r, "load pubkey \"%s\"", tmp);
1829 		if (sshkey_is_cert(public))
1830 			fatal_f("key \"%s\" type %s cannot be certified",
1831 			    tmp, sshkey_type(public));
1832 
1833 		/* Prepare certificate to sign */
1834 		if ((r = sshkey_to_certified(public)) != 0)
1835 			fatal_r(r, "Could not upgrade key %s to certificate", tmp);
1836 		public->cert->type = cert_key_type;
1837 		public->cert->serial = (u_int64_t)cert_serial;
1838 		public->cert->key_id = xstrdup(cert_key_id);
1839 		public->cert->nprincipals = n;
1840 		public->cert->principals = plist;
1841 		public->cert->valid_after = cert_valid_from;
1842 		public->cert->valid_before = cert_valid_to;
1843 		prepare_options_buf(public->cert->critical, OPTIONS_CRITICAL);
1844 		prepare_options_buf(public->cert->extensions,
1845 		    OPTIONS_EXTENSIONS);
1846 		if ((r = sshkey_from_private(ca,
1847 		    &public->cert->signature_key)) != 0)
1848 			fatal_r(r, "sshkey_from_private (ca key)");
1849 
1850 		if (agent_fd != -1 && (ca->flags & SSHKEY_FLAG_EXT) != 0) {
1851 			if ((r = sshkey_certify_custom(public, ca,
1852 			    key_type_name, sk_provider, NULL, agent_signer,
1853 			    &agent_fd)) != 0)
1854 				fatal_r(r, "Couldn't certify %s via agent", tmp);
1855 		} else {
1856 			if (sshkey_is_sk(ca) &&
1857 			    (ca->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1858 				notifier = notify_start(0,
1859 				    "Confirm user presence for key %s %s",
1860 				    sshkey_type(ca), ca_fp);
1861 			}
1862 			r = sshkey_certify(public, ca, key_type_name,
1863 			    sk_provider, pin);
1864 			notify_complete(notifier, "User presence confirmed");
1865 			if (r != 0)
1866 				fatal_r(r, "Couldn't certify key %s", tmp);
1867 		}
1868 
1869 		if ((cp = strrchr(tmp, '.')) != NULL && strcmp(cp, ".pub") == 0)
1870 			*cp = '\0';
1871 		xasprintf(&out, "%s-cert.pub", tmp);
1872 		free(tmp);
1873 
1874 		if ((r = sshkey_save_public(public, out, comment)) != 0) {
1875 			fatal_r(r, "Unable to save public key to %s",
1876 			    identity_file);
1877 		}
1878 
1879 		if (!quiet) {
1880 			sshkey_format_cert_validity(public->cert,
1881 			    valid, sizeof(valid));
1882 			logit("Signed %s key %s: id \"%s\" serial %llu%s%s "
1883 			    "valid %s", sshkey_cert_type(public),
1884 			    out, public->cert->key_id,
1885 			    (unsigned long long)public->cert->serial,
1886 			    cert_principals != NULL ? " for " : "",
1887 			    cert_principals != NULL ? cert_principals : "",
1888 			    valid);
1889 		}
1890 
1891 		sshkey_free(public);
1892 		free(out);
1893 		if (cert_serial_autoinc)
1894 			cert_serial++;
1895 	}
1896 	if (pin != NULL)
1897 		freezero(pin, strlen(pin));
1898 	free(ca_fp);
1899 #ifdef ENABLE_PKCS11
1900 	pkcs11_terminate();
1901 #endif
1902 	exit(0);
1903 }
1904 
1905 static u_int64_t
1906 parse_relative_time(const char *s, time_t now)
1907 {
1908 	int64_t mul, secs;
1909 
1910 	mul = *s == '-' ? -1 : 1;
1911 
1912 	if ((secs = convtime(s + 1)) == -1)
1913 		fatal("Invalid relative certificate time %s", s);
1914 	if (mul == -1 && secs > now)
1915 		fatal("Certificate time %s cannot be represented", s);
1916 	return now + (u_int64_t)(secs * mul);
1917 }
1918 
1919 static void
1920 parse_hex_u64(const char *s, uint64_t *up)
1921 {
1922 	char *ep;
1923 	unsigned long long ull;
1924 
1925 	errno = 0;
1926 	ull = strtoull(s, &ep, 16);
1927 	if (*s == '\0' || *ep != '\0')
1928 		fatal("Invalid certificate time: not a number");
1929 	if (errno == ERANGE && ull == ULONG_MAX)
1930 		fatal_fr(SSH_ERR_SYSTEM_ERROR, "Invalid certificate time");
1931 	*up = (uint64_t)ull;
1932 }
1933 
1934 static void
1935 parse_cert_times(char *timespec)
1936 {
1937 	char *from, *to;
1938 	time_t now = time(NULL);
1939 	int64_t secs;
1940 
1941 	/* +timespec relative to now */
1942 	if (*timespec == '+' && strchr(timespec, ':') == NULL) {
1943 		if ((secs = convtime(timespec + 1)) == -1)
1944 			fatal("Invalid relative certificate life %s", timespec);
1945 		cert_valid_to = now + secs;
1946 		/*
1947 		 * Backdate certificate one minute to avoid problems on hosts
1948 		 * with poorly-synchronised clocks.
1949 		 */
1950 		cert_valid_from = ((now - 59)/ 60) * 60;
1951 		return;
1952 	}
1953 
1954 	/*
1955 	 * from:to, where
1956 	 * from := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | 0x... | "always"
1957 	 *   to := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | 0x... | "forever"
1958 	 */
1959 	from = xstrdup(timespec);
1960 	to = strchr(from, ':');
1961 	if (to == NULL || from == to || *(to + 1) == '\0')
1962 		fatal("Invalid certificate life specification %s", timespec);
1963 	*to++ = '\0';
1964 
1965 	if (*from == '-' || *from == '+')
1966 		cert_valid_from = parse_relative_time(from, now);
1967 	else if (strcmp(from, "always") == 0)
1968 		cert_valid_from = 0;
1969 	else if (strncmp(from, "0x", 2) == 0)
1970 		parse_hex_u64(from, &cert_valid_from);
1971 	else if (parse_absolute_time(from, &cert_valid_from) != 0)
1972 		fatal("Invalid from time \"%s\"", from);
1973 
1974 	if (*to == '-' || *to == '+')
1975 		cert_valid_to = parse_relative_time(to, now);
1976 	else if (strcmp(to, "forever") == 0)
1977 		cert_valid_to = ~(u_int64_t)0;
1978 	else if (strncmp(to, "0x", 2) == 0)
1979 		parse_hex_u64(to, &cert_valid_to);
1980 	else if (parse_absolute_time(to, &cert_valid_to) != 0)
1981 		fatal("Invalid to time \"%s\"", to);
1982 
1983 	if (cert_valid_to <= cert_valid_from)
1984 		fatal("Empty certificate validity interval");
1985 	free(from);
1986 }
1987 
1988 static void
1989 add_cert_option(char *opt)
1990 {
1991 	char *val, *cp;
1992 	int iscrit = 0;
1993 
1994 	if (strcasecmp(opt, "clear") == 0)
1995 		certflags_flags = 0;
1996 	else if (strcasecmp(opt, "no-x11-forwarding") == 0)
1997 		certflags_flags &= ~CERTOPT_X_FWD;
1998 	else if (strcasecmp(opt, "permit-x11-forwarding") == 0)
1999 		certflags_flags |= CERTOPT_X_FWD;
2000 	else if (strcasecmp(opt, "no-agent-forwarding") == 0)
2001 		certflags_flags &= ~CERTOPT_AGENT_FWD;
2002 	else if (strcasecmp(opt, "permit-agent-forwarding") == 0)
2003 		certflags_flags |= CERTOPT_AGENT_FWD;
2004 	else if (strcasecmp(opt, "no-port-forwarding") == 0)
2005 		certflags_flags &= ~CERTOPT_PORT_FWD;
2006 	else if (strcasecmp(opt, "permit-port-forwarding") == 0)
2007 		certflags_flags |= CERTOPT_PORT_FWD;
2008 	else if (strcasecmp(opt, "no-pty") == 0)
2009 		certflags_flags &= ~CERTOPT_PTY;
2010 	else if (strcasecmp(opt, "permit-pty") == 0)
2011 		certflags_flags |= CERTOPT_PTY;
2012 	else if (strcasecmp(opt, "no-user-rc") == 0)
2013 		certflags_flags &= ~CERTOPT_USER_RC;
2014 	else if (strcasecmp(opt, "permit-user-rc") == 0)
2015 		certflags_flags |= CERTOPT_USER_RC;
2016 	else if (strcasecmp(opt, "touch-required") == 0)
2017 		certflags_flags &= ~CERTOPT_NO_REQUIRE_USER_PRESENCE;
2018 	else if (strcasecmp(opt, "no-touch-required") == 0)
2019 		certflags_flags |= CERTOPT_NO_REQUIRE_USER_PRESENCE;
2020 	else if (strcasecmp(opt, "no-verify-required") == 0)
2021 		certflags_flags &= ~CERTOPT_REQUIRE_VERIFY;
2022 	else if (strcasecmp(opt, "verify-required") == 0)
2023 		certflags_flags |= CERTOPT_REQUIRE_VERIFY;
2024 	else if (strncasecmp(opt, "force-command=", 14) == 0) {
2025 		val = opt + 14;
2026 		if (*val == '\0')
2027 			fatal("Empty force-command option");
2028 		if (certflags_command != NULL)
2029 			fatal("force-command already specified");
2030 		certflags_command = xstrdup(val);
2031 	} else if (strncasecmp(opt, "source-address=", 15) == 0) {
2032 		val = opt + 15;
2033 		if (*val == '\0')
2034 			fatal("Empty source-address option");
2035 		if (certflags_src_addr != NULL)
2036 			fatal("source-address already specified");
2037 		if (addr_match_cidr_list(NULL, val) != 0)
2038 			fatal("Invalid source-address list");
2039 		certflags_src_addr = xstrdup(val);
2040 	} else if (strncasecmp(opt, "extension:", 10) == 0 ||
2041 		    (iscrit = (strncasecmp(opt, "critical:", 9) == 0))) {
2042 		val = xstrdup(strchr(opt, ':') + 1);
2043 		if ((cp = strchr(val, '=')) != NULL)
2044 			*cp++ = '\0';
2045 		cert_ext_add(val, cp, iscrit);
2046 		free(val);
2047 	} else
2048 		fatal("Unsupported certificate option \"%s\"", opt);
2049 }
2050 
2051 static void
2052 show_options(struct sshbuf *optbuf, int in_critical)
2053 {
2054 	char *name, *arg, *hex;
2055 	struct sshbuf *options, *option = NULL;
2056 	int r;
2057 
2058 	if ((options = sshbuf_fromb(optbuf)) == NULL)
2059 		fatal_f("sshbuf_fromb failed");
2060 	while (sshbuf_len(options) != 0) {
2061 		sshbuf_free(option);
2062 		option = NULL;
2063 		if ((r = sshbuf_get_cstring(options, &name, NULL)) != 0 ||
2064 		    (r = sshbuf_froms(options, &option)) != 0)
2065 			fatal_fr(r, "parse option");
2066 		printf("                %s", name);
2067 		if (!in_critical &&
2068 		    (strcmp(name, "permit-X11-forwarding") == 0 ||
2069 		    strcmp(name, "permit-agent-forwarding") == 0 ||
2070 		    strcmp(name, "permit-port-forwarding") == 0 ||
2071 		    strcmp(name, "permit-pty") == 0 ||
2072 		    strcmp(name, "permit-user-rc") == 0 ||
2073 		    strcmp(name, "no-touch-required") == 0)) {
2074 			printf("\n");
2075 		} else if (in_critical &&
2076 		    (strcmp(name, "force-command") == 0 ||
2077 		    strcmp(name, "source-address") == 0)) {
2078 			if ((r = sshbuf_get_cstring(option, &arg, NULL)) != 0)
2079 				fatal_fr(r, "parse critical");
2080 			printf(" %s\n", arg);
2081 			free(arg);
2082 		} else if (in_critical &&
2083 		    strcmp(name, "verify-required") == 0) {
2084 			printf("\n");
2085 		} else if (sshbuf_len(option) > 0) {
2086 			hex = sshbuf_dtob16(option);
2087 			printf(" UNKNOWN OPTION: %s (len %zu)\n",
2088 			    hex, sshbuf_len(option));
2089 			sshbuf_reset(option);
2090 			free(hex);
2091 		} else
2092 			printf(" UNKNOWN FLAG OPTION\n");
2093 		free(name);
2094 		if (sshbuf_len(option) != 0)
2095 			fatal("Option corrupt: extra data at end");
2096 	}
2097 	sshbuf_free(option);
2098 	sshbuf_free(options);
2099 }
2100 
2101 static void
2102 print_cert(struct sshkey *key)
2103 {
2104 	char valid[64], *key_fp, *ca_fp;
2105 	u_int i;
2106 
2107 	key_fp = sshkey_fingerprint(key, fingerprint_hash, SSH_FP_DEFAULT);
2108 	ca_fp = sshkey_fingerprint(key->cert->signature_key,
2109 	    fingerprint_hash, SSH_FP_DEFAULT);
2110 	if (key_fp == NULL || ca_fp == NULL)
2111 		fatal_f("sshkey_fingerprint fail");
2112 	sshkey_format_cert_validity(key->cert, valid, sizeof(valid));
2113 
2114 	printf("        Type: %s %s certificate\n", sshkey_ssh_name(key),
2115 	    sshkey_cert_type(key));
2116 	printf("        Public key: %s %s\n", sshkey_type(key), key_fp);
2117 	printf("        Signing CA: %s %s (using %s)\n",
2118 	    sshkey_type(key->cert->signature_key), ca_fp,
2119 	    key->cert->signature_type);
2120 	printf("        Key ID: \"%s\"\n", key->cert->key_id);
2121 	printf("        Serial: %llu\n", (unsigned long long)key->cert->serial);
2122 	printf("        Valid: %s\n", valid);
2123 	printf("        Principals: ");
2124 	if (key->cert->nprincipals == 0)
2125 		printf("(none)\n");
2126 	else {
2127 		for (i = 0; i < key->cert->nprincipals; i++)
2128 			printf("\n                %s",
2129 			    key->cert->principals[i]);
2130 		printf("\n");
2131 	}
2132 	printf("        Critical Options: ");
2133 	if (sshbuf_len(key->cert->critical) == 0)
2134 		printf("(none)\n");
2135 	else {
2136 		printf("\n");
2137 		show_options(key->cert->critical, 1);
2138 	}
2139 	printf("        Extensions: ");
2140 	if (sshbuf_len(key->cert->extensions) == 0)
2141 		printf("(none)\n");
2142 	else {
2143 		printf("\n");
2144 		show_options(key->cert->extensions, 0);
2145 	}
2146 }
2147 
2148 static void
2149 do_show_cert(struct passwd *pw)
2150 {
2151 	struct sshkey *key = NULL;
2152 	struct stat st;
2153 	int r, is_stdin = 0, ok = 0;
2154 	FILE *f;
2155 	char *cp, *line = NULL;
2156 	const char *path;
2157 	size_t linesize = 0;
2158 	u_long lnum = 0;
2159 
2160 	if (!have_identity)
2161 		ask_filename(pw, "Enter file in which the key is");
2162 	if (strcmp(identity_file, "-") != 0 && stat(identity_file, &st) == -1)
2163 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
2164 
2165 	path = identity_file;
2166 	if (strcmp(path, "-") == 0) {
2167 		f = stdin;
2168 		path = "(stdin)";
2169 		is_stdin = 1;
2170 	} else if ((f = fopen(identity_file, "r")) == NULL)
2171 		fatal("fopen %s: %s", identity_file, strerror(errno));
2172 
2173 	while (getline(&line, &linesize, f) != -1) {
2174 		lnum++;
2175 		sshkey_free(key);
2176 		key = NULL;
2177 		/* Trim leading space and comments */
2178 		cp = line + strspn(line, " \t");
2179 		if (*cp == '#' || *cp == '\0')
2180 			continue;
2181 		if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2182 			fatal("sshkey_new");
2183 		if ((r = sshkey_read(key, &cp)) != 0) {
2184 			error_r(r, "%s:%lu: invalid key", path, lnum);
2185 			continue;
2186 		}
2187 		if (!sshkey_is_cert(key)) {
2188 			error("%s:%lu is not a certificate", path, lnum);
2189 			continue;
2190 		}
2191 		ok = 1;
2192 		if (!is_stdin && lnum == 1)
2193 			printf("%s:\n", path);
2194 		else
2195 			printf("%s:%lu:\n", path, lnum);
2196 		print_cert(key);
2197 	}
2198 	free(line);
2199 	sshkey_free(key);
2200 	fclose(f);
2201 	exit(ok ? 0 : 1);
2202 }
2203 
2204 static void
2205 load_krl(const char *path, struct ssh_krl **krlp)
2206 {
2207 	struct sshbuf *krlbuf;
2208 	int r;
2209 
2210 	if ((r = sshbuf_load_file(path, &krlbuf)) != 0)
2211 		fatal_r(r, "Unable to load KRL %s", path);
2212 	/* XXX check sigs */
2213 	if ((r = ssh_krl_from_blob(krlbuf, krlp, NULL, 0)) != 0 ||
2214 	    *krlp == NULL)
2215 		fatal_r(r, "Invalid KRL file %s", path);
2216 	sshbuf_free(krlbuf);
2217 }
2218 
2219 static void
2220 hash_to_blob(const char *cp, u_char **blobp, size_t *lenp,
2221     const char *file, u_long lnum)
2222 {
2223 	char *tmp;
2224 	size_t tlen;
2225 	struct sshbuf *b;
2226 	int r;
2227 
2228 	if (strncmp(cp, "SHA256:", 7) != 0)
2229 		fatal("%s:%lu: unsupported hash algorithm", file, lnum);
2230 	cp += 7;
2231 
2232 	/*
2233 	 * OpenSSH base64 hashes omit trailing '='
2234 	 * characters; put them back for decode.
2235 	 */
2236 	tlen = strlen(cp);
2237 	tmp = xmalloc(tlen + 4 + 1);
2238 	strlcpy(tmp, cp, tlen + 1);
2239 	while ((tlen % 4) != 0) {
2240 		tmp[tlen++] = '=';
2241 		tmp[tlen] = '\0';
2242 	}
2243 	if ((b = sshbuf_new()) == NULL)
2244 		fatal_f("sshbuf_new failed");
2245 	if ((r = sshbuf_b64tod(b, tmp)) != 0)
2246 		fatal_r(r, "%s:%lu: decode hash failed", file, lnum);
2247 	free(tmp);
2248 	*lenp = sshbuf_len(b);
2249 	*blobp = xmalloc(*lenp);
2250 	memcpy(*blobp, sshbuf_ptr(b), *lenp);
2251 	sshbuf_free(b);
2252 }
2253 
2254 static void
2255 update_krl_from_file(struct passwd *pw, const char *file, int wild_ca,
2256     const struct sshkey *ca, struct ssh_krl *krl)
2257 {
2258 	struct sshkey *key = NULL;
2259 	u_long lnum = 0;
2260 	char *path, *cp, *ep, *line = NULL;
2261 	u_char *blob = NULL;
2262 	size_t blen = 0, linesize = 0;
2263 	unsigned long long serial, serial2;
2264 	int i, was_explicit_key, was_sha1, was_sha256, was_hash, r;
2265 	FILE *krl_spec;
2266 
2267 	path = tilde_expand_filename(file, pw->pw_uid);
2268 	if (strcmp(path, "-") == 0) {
2269 		krl_spec = stdin;
2270 		free(path);
2271 		path = xstrdup("(standard input)");
2272 	} else if ((krl_spec = fopen(path, "r")) == NULL)
2273 		fatal("fopen %s: %s", path, strerror(errno));
2274 
2275 	if (!quiet)
2276 		printf("Revoking from %s\n", path);
2277 	while (getline(&line, &linesize, krl_spec) != -1) {
2278 		lnum++;
2279 		was_explicit_key = was_sha1 = was_sha256 = was_hash = 0;
2280 		cp = line + strspn(line, " \t");
2281 		/* Trim trailing space, comments and strip \n */
2282 		for (i = 0, r = -1; cp[i] != '\0'; i++) {
2283 			if (cp[i] == '#' || cp[i] == '\n') {
2284 				cp[i] = '\0';
2285 				break;
2286 			}
2287 			if (cp[i] == ' ' || cp[i] == '\t') {
2288 				/* Remember the start of a span of whitespace */
2289 				if (r == -1)
2290 					r = i;
2291 			} else
2292 				r = -1;
2293 		}
2294 		if (r != -1)
2295 			cp[r] = '\0';
2296 		if (*cp == '\0')
2297 			continue;
2298 		if (strncasecmp(cp, "serial:", 7) == 0) {
2299 			if (ca == NULL && !wild_ca) {
2300 				fatal("revoking certificates by serial number "
2301 				    "requires specification of a CA key");
2302 			}
2303 			cp += 7;
2304 			cp = cp + strspn(cp, " \t");
2305 			errno = 0;
2306 			serial = strtoull(cp, &ep, 0);
2307 			if (*cp == '\0' || (*ep != '\0' && *ep != '-'))
2308 				fatal("%s:%lu: invalid serial \"%s\"",
2309 				    path, lnum, cp);
2310 			if (errno == ERANGE && serial == ULLONG_MAX)
2311 				fatal("%s:%lu: serial out of range",
2312 				    path, lnum);
2313 			serial2 = serial;
2314 			if (*ep == '-') {
2315 				cp = ep + 1;
2316 				errno = 0;
2317 				serial2 = strtoull(cp, &ep, 0);
2318 				if (*cp == '\0' || *ep != '\0')
2319 					fatal("%s:%lu: invalid serial \"%s\"",
2320 					    path, lnum, cp);
2321 				if (errno == ERANGE && serial2 == ULLONG_MAX)
2322 					fatal("%s:%lu: serial out of range",
2323 					    path, lnum);
2324 				if (serial2 <= serial)
2325 					fatal("%s:%lu: invalid serial range "
2326 					    "%llu:%llu", path, lnum,
2327 					    (unsigned long long)serial,
2328 					    (unsigned long long)serial2);
2329 			}
2330 			if (ssh_krl_revoke_cert_by_serial_range(krl,
2331 			    ca, serial, serial2) != 0) {
2332 				fatal_f("revoke serial failed");
2333 			}
2334 		} else if (strncasecmp(cp, "id:", 3) == 0) {
2335 			if (ca == NULL && !wild_ca) {
2336 				fatal("revoking certificates by key ID "
2337 				    "requires specification of a CA key");
2338 			}
2339 			cp += 3;
2340 			cp = cp + strspn(cp, " \t");
2341 			if (ssh_krl_revoke_cert_by_key_id(krl, ca, cp) != 0)
2342 				fatal_f("revoke key ID failed");
2343 		} else if (strncasecmp(cp, "hash:", 5) == 0) {
2344 			cp += 5;
2345 			cp = cp + strspn(cp, " \t");
2346 			hash_to_blob(cp, &blob, &blen, file, lnum);
2347 			r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2348 			if (r != 0)
2349 				fatal_fr(r, "revoke key failed");
2350 		} else {
2351 			if (strncasecmp(cp, "key:", 4) == 0) {
2352 				cp += 4;
2353 				cp = cp + strspn(cp, " \t");
2354 				was_explicit_key = 1;
2355 			} else if (strncasecmp(cp, "sha1:", 5) == 0) {
2356 				cp += 5;
2357 				cp = cp + strspn(cp, " \t");
2358 				was_sha1 = 1;
2359 			} else if (strncasecmp(cp, "sha256:", 7) == 0) {
2360 				cp += 7;
2361 				cp = cp + strspn(cp, " \t");
2362 				was_sha256 = 1;
2363 				/*
2364 				 * Just try to process the line as a key.
2365 				 * Parsing will fail if it isn't.
2366 				 */
2367 			}
2368 			if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2369 				fatal("sshkey_new");
2370 			if ((r = sshkey_read(key, &cp)) != 0)
2371 				fatal_r(r, "%s:%lu: invalid key", path, lnum);
2372 			if (was_explicit_key)
2373 				r = ssh_krl_revoke_key_explicit(krl, key);
2374 			else if (was_sha1) {
2375 				if (sshkey_fingerprint_raw(key,
2376 				    SSH_DIGEST_SHA1, &blob, &blen) != 0) {
2377 					fatal("%s:%lu: fingerprint failed",
2378 					    file, lnum);
2379 				}
2380 				r = ssh_krl_revoke_key_sha1(krl, blob, blen);
2381 			} else if (was_sha256) {
2382 				if (sshkey_fingerprint_raw(key,
2383 				    SSH_DIGEST_SHA256, &blob, &blen) != 0) {
2384 					fatal("%s:%lu: fingerprint failed",
2385 					    file, lnum);
2386 				}
2387 				r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2388 			} else
2389 				r = ssh_krl_revoke_key(krl, key);
2390 			if (r != 0)
2391 				fatal_fr(r, "revoke key failed");
2392 			freezero(blob, blen);
2393 			blob = NULL;
2394 			blen = 0;
2395 			sshkey_free(key);
2396 		}
2397 	}
2398 	if (strcmp(path, "-") != 0)
2399 		fclose(krl_spec);
2400 	free(line);
2401 	free(path);
2402 }
2403 
2404 static void
2405 do_gen_krl(struct passwd *pw, int updating, const char *ca_key_path,
2406     unsigned long long krl_version, const char *krl_comment,
2407     int argc, char **argv)
2408 {
2409 	struct ssh_krl *krl;
2410 	struct stat sb;
2411 	struct sshkey *ca = NULL;
2412 	int i, r, wild_ca = 0;
2413 	char *tmp;
2414 	struct sshbuf *kbuf;
2415 
2416 	if (*identity_file == '\0')
2417 		fatal("KRL generation requires an output file");
2418 	if (stat(identity_file, &sb) == -1) {
2419 		if (errno != ENOENT)
2420 			fatal("Cannot access KRL \"%s\": %s",
2421 			    identity_file, strerror(errno));
2422 		if (updating)
2423 			fatal("KRL \"%s\" does not exist", identity_file);
2424 	}
2425 	if (ca_key_path != NULL) {
2426 		if (strcasecmp(ca_key_path, "none") == 0)
2427 			wild_ca = 1;
2428 		else {
2429 			tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
2430 			if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
2431 				fatal_r(r, "Cannot load CA public key %s", tmp);
2432 			free(tmp);
2433 		}
2434 	}
2435 
2436 	if (updating)
2437 		load_krl(identity_file, &krl);
2438 	else if ((krl = ssh_krl_init()) == NULL)
2439 		fatal("couldn't create KRL");
2440 
2441 	if (krl_version != 0)
2442 		ssh_krl_set_version(krl, krl_version);
2443 	if (krl_comment != NULL)
2444 		ssh_krl_set_comment(krl, krl_comment);
2445 
2446 	for (i = 0; i < argc; i++)
2447 		update_krl_from_file(pw, argv[i], wild_ca, ca, krl);
2448 
2449 	if ((kbuf = sshbuf_new()) == NULL)
2450 		fatal("sshbuf_new failed");
2451 	if (ssh_krl_to_blob(krl, kbuf, NULL, 0) != 0)
2452 		fatal("Couldn't generate KRL");
2453 	if ((r = sshbuf_write_file(identity_file, kbuf)) != 0)
2454 		fatal("write %s: %s", identity_file, strerror(errno));
2455 	sshbuf_free(kbuf);
2456 	ssh_krl_free(krl);
2457 	sshkey_free(ca);
2458 }
2459 
2460 static void
2461 do_check_krl(struct passwd *pw, int print_krl, int argc, char **argv)
2462 {
2463 	int i, r, ret = 0;
2464 	char *comment;
2465 	struct ssh_krl *krl;
2466 	struct sshkey *k;
2467 
2468 	if (*identity_file == '\0')
2469 		fatal("KRL checking requires an input file");
2470 	load_krl(identity_file, &krl);
2471 	if (print_krl)
2472 		krl_dump(krl, stdout);
2473 	for (i = 0; i < argc; i++) {
2474 		if ((r = sshkey_load_public(argv[i], &k, &comment)) != 0)
2475 			fatal_r(r, "Cannot load public key %s", argv[i]);
2476 		r = ssh_krl_check_key(krl, k);
2477 		printf("%s%s%s%s: %s\n", argv[i],
2478 		    *comment ? " (" : "", comment, *comment ? ")" : "",
2479 		    r == 0 ? "ok" : "REVOKED");
2480 		if (r != 0)
2481 			ret = 1;
2482 		sshkey_free(k);
2483 		free(comment);
2484 	}
2485 	ssh_krl_free(krl);
2486 	exit(ret);
2487 }
2488 
2489 static struct sshkey *
2490 load_sign_key(const char *keypath, const struct sshkey *pubkey)
2491 {
2492 	size_t i, slen, plen = strlen(keypath);
2493 	char *privpath = xstrdup(keypath);
2494 	static const char * const suffixes[] = { "-cert.pub", ".pub", NULL };
2495 	struct sshkey *ret = NULL, *privkey = NULL;
2496 	int r, waspub = 0;
2497 	struct stat st;
2498 
2499 	/*
2500 	 * If passed a public key filename, then try to locate the corresponding
2501 	 * private key. This lets us specify certificates on the command-line
2502 	 * and have ssh-keygen find the appropriate private key.
2503 	 */
2504 	for (i = 0; suffixes[i]; i++) {
2505 		slen = strlen(suffixes[i]);
2506 		if (plen <= slen ||
2507 		    strcmp(privpath + plen - slen, suffixes[i]) != 0)
2508 			continue;
2509 		privpath[plen - slen] = '\0';
2510 		debug_f("%s looks like a public key, using private key "
2511 		    "path %s instead", keypath, privpath);
2512 		waspub = 1;
2513 	}
2514 	if (waspub && stat(privpath, &st) != 0 && errno == ENOENT)
2515 		fatal("No private key found for public key \"%s\"", keypath);
2516 	if ((r = sshkey_load_private(privpath, "", &privkey, NULL)) != 0 &&
2517 	    (r != SSH_ERR_KEY_WRONG_PASSPHRASE)) {
2518 		debug_fr(r, "load private key \"%s\"", privpath);
2519 		fatal("No private key found for \"%s\"", privpath);
2520 	} else if (privkey == NULL)
2521 		privkey = load_identity(privpath, NULL);
2522 
2523 	if (!sshkey_equal_public(pubkey, privkey)) {
2524 		error("Public key %s doesn't match private %s",
2525 		    keypath, privpath);
2526 		goto done;
2527 	}
2528 	if (sshkey_is_cert(pubkey) && !sshkey_is_cert(privkey)) {
2529 		/*
2530 		 * Graft the certificate onto the private key to make
2531 		 * it capable of signing.
2532 		 */
2533 		if ((r = sshkey_to_certified(privkey)) != 0) {
2534 			error_fr(r, "sshkey_to_certified");
2535 			goto done;
2536 		}
2537 		if ((r = sshkey_cert_copy(pubkey, privkey)) != 0) {
2538 			error_fr(r, "sshkey_cert_copy");
2539 			goto done;
2540 		}
2541 	}
2542 	/* success */
2543 	ret = privkey;
2544 	privkey = NULL;
2545  done:
2546 	sshkey_free(privkey);
2547 	free(privpath);
2548 	return ret;
2549 }
2550 
2551 static int
2552 sign_one(struct sshkey *signkey, const char *filename, int fd,
2553     const char *sig_namespace, const char *hashalg, sshsig_signer *signer,
2554     void *signer_ctx)
2555 {
2556 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2557 	int r = SSH_ERR_INTERNAL_ERROR, wfd = -1, oerrno;
2558 	char *wfile = NULL, *asig = NULL, *fp = NULL;
2559 	char *pin = NULL, *prompt = NULL;
2560 
2561 	if (!quiet) {
2562 		if (fd == STDIN_FILENO)
2563 			fprintf(stderr, "Signing data on standard input\n");
2564 		else
2565 			fprintf(stderr, "Signing file %s\n", filename);
2566 	}
2567 	if (signer == NULL && sshkey_is_sk(signkey)) {
2568 		if ((signkey->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
2569 			xasprintf(&prompt, "Enter PIN for %s key: ",
2570 			    sshkey_type(signkey));
2571 			if ((pin = read_passphrase(prompt,
2572 			    RP_ALLOW_STDIN)) == NULL)
2573 				fatal_f("couldn't read PIN");
2574 		}
2575 		if ((signkey->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
2576 			if ((fp = sshkey_fingerprint(signkey, fingerprint_hash,
2577 			    SSH_FP_DEFAULT)) == NULL)
2578 				fatal_f("fingerprint failed");
2579 			fprintf(stderr, "Confirm user presence for key %s %s\n",
2580 			    sshkey_type(signkey), fp);
2581 			free(fp);
2582 		}
2583 	}
2584 	if ((r = sshsig_sign_fd(signkey, hashalg, sk_provider, pin,
2585 	    fd, sig_namespace, &sigbuf, signer, signer_ctx)) != 0) {
2586 		error_r(r, "Signing %s failed", filename);
2587 		goto out;
2588 	}
2589 	if ((r = sshsig_armor(sigbuf, &abuf)) != 0) {
2590 		error_fr(r, "sshsig_armor");
2591 		goto out;
2592 	}
2593 	if ((asig = sshbuf_dup_string(abuf)) == NULL) {
2594 		error_f("buffer error");
2595 		r = SSH_ERR_ALLOC_FAIL;
2596 		goto out;
2597 	}
2598 
2599 	if (fd == STDIN_FILENO) {
2600 		fputs(asig, stdout);
2601 		fflush(stdout);
2602 	} else {
2603 		xasprintf(&wfile, "%s.sig", filename);
2604 		if (confirm_overwrite(wfile)) {
2605 			if ((wfd = open(wfile, O_WRONLY|O_CREAT|O_TRUNC,
2606 			    0666)) == -1) {
2607 				oerrno = errno;
2608 				error("Cannot open %s: %s",
2609 				    wfile, strerror(errno));
2610 				errno = oerrno;
2611 				r = SSH_ERR_SYSTEM_ERROR;
2612 				goto out;
2613 			}
2614 			if (atomicio(vwrite, wfd, asig,
2615 			    strlen(asig)) != strlen(asig)) {
2616 				oerrno = errno;
2617 				error("Cannot write to %s: %s",
2618 				    wfile, strerror(errno));
2619 				errno = oerrno;
2620 				r = SSH_ERR_SYSTEM_ERROR;
2621 				goto out;
2622 			}
2623 			if (!quiet) {
2624 				fprintf(stderr, "Write signature to %s\n",
2625 				    wfile);
2626 			}
2627 		}
2628 	}
2629 	/* success */
2630 	r = 0;
2631  out:
2632 	free(wfile);
2633 	free(prompt);
2634 	free(asig);
2635 	if (pin != NULL)
2636 		freezero(pin, strlen(pin));
2637 	sshbuf_free(abuf);
2638 	sshbuf_free(sigbuf);
2639 	if (wfd != -1)
2640 		close(wfd);
2641 	return r;
2642 }
2643 
2644 static int
2645 sig_process_opts(char * const *opts, size_t nopts, char **hashalgp,
2646     uint64_t *verify_timep, int *print_pubkey)
2647 {
2648 	size_t i;
2649 	time_t now;
2650 
2651 	if (verify_timep != NULL)
2652 		*verify_timep = 0;
2653 	if (print_pubkey != NULL)
2654 		*print_pubkey = 0;
2655 	if (hashalgp != NULL)
2656 		*hashalgp = NULL;
2657 	for (i = 0; i < nopts; i++) {
2658 		if (hashalgp != NULL &&
2659 		    strncasecmp(opts[i], "hashalg=", 8) == 0) {
2660 			*hashalgp = xstrdup(opts[i] + 8);
2661 		} else if (verify_timep &&
2662 		    strncasecmp(opts[i], "verify-time=", 12) == 0) {
2663 			if (parse_absolute_time(opts[i] + 12,
2664 			    verify_timep) != 0 || *verify_timep == 0) {
2665 				error("Invalid \"verify-time\" option");
2666 				return SSH_ERR_INVALID_ARGUMENT;
2667 			}
2668 		} else if (print_pubkey &&
2669 		    strcasecmp(opts[i], "print-pubkey") == 0) {
2670 			*print_pubkey = 1;
2671 		} else {
2672 			error("Invalid option \"%s\"", opts[i]);
2673 			return SSH_ERR_INVALID_ARGUMENT;
2674 		}
2675 	}
2676 	if (verify_timep && *verify_timep == 0) {
2677 		if ((now = time(NULL)) < 0) {
2678 			error("Time is before epoch");
2679 			return SSH_ERR_INVALID_ARGUMENT;
2680 		}
2681 		*verify_timep = (uint64_t)now;
2682 	}
2683 	return 0;
2684 }
2685 
2686 
2687 static int
2688 sig_sign(const char *keypath, const char *sig_namespace, int require_agent,
2689     int argc, char **argv, char * const *opts, size_t nopts)
2690 {
2691 	int i, fd = -1, r, ret = -1;
2692 	int agent_fd = -1;
2693 	struct sshkey *pubkey = NULL, *privkey = NULL, *signkey = NULL;
2694 	sshsig_signer *signer = NULL;
2695 	char *hashalg = NULL;
2696 
2697 	/* Check file arguments. */
2698 	for (i = 0; i < argc; i++) {
2699 		if (strcmp(argv[i], "-") != 0)
2700 			continue;
2701 		if (i > 0 || argc > 1)
2702 			fatal("Cannot sign mix of paths and standard input");
2703 	}
2704 
2705 	if (sig_process_opts(opts, nopts, &hashalg, NULL, NULL) != 0)
2706 		goto done; /* error already logged */
2707 
2708 	if ((r = sshkey_load_public(keypath, &pubkey, NULL)) != 0) {
2709 		error_r(r, "Couldn't load public key %s", keypath);
2710 		goto done;
2711 	}
2712 
2713 	if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
2714 		if (require_agent)
2715 			fatal("Couldn't get agent socket");
2716 		debug_r(r, "Couldn't get agent socket");
2717 	} else {
2718 		if ((r = ssh_agent_has_key(agent_fd, pubkey)) == 0)
2719 			signer = agent_signer;
2720 		else {
2721 			if (require_agent)
2722 				fatal("Couldn't find key in agent");
2723 			debug_r(r, "Couldn't find key in agent");
2724 		}
2725 	}
2726 
2727 	if (signer == NULL) {
2728 		/* Not using agent - try to load private key */
2729 		if ((privkey = load_sign_key(keypath, pubkey)) == NULL)
2730 			goto done;
2731 		signkey = privkey;
2732 	} else {
2733 		/* Will use key in agent */
2734 		signkey = pubkey;
2735 	}
2736 
2737 	if (argc == 0) {
2738 		if ((r = sign_one(signkey, "(stdin)", STDIN_FILENO,
2739 		    sig_namespace, hashalg, signer, &agent_fd)) != 0)
2740 			goto done;
2741 	} else {
2742 		for (i = 0; i < argc; i++) {
2743 			if (strcmp(argv[i], "-") == 0)
2744 				fd = STDIN_FILENO;
2745 			else if ((fd = open(argv[i], O_RDONLY)) == -1) {
2746 				error("Cannot open %s for signing: %s",
2747 				    argv[i], strerror(errno));
2748 				goto done;
2749 			}
2750 			if ((r = sign_one(signkey, argv[i], fd, sig_namespace,
2751 			    hashalg, signer, &agent_fd)) != 0)
2752 				goto done;
2753 			if (fd != STDIN_FILENO)
2754 				close(fd);
2755 			fd = -1;
2756 		}
2757 	}
2758 
2759 	ret = 0;
2760 done:
2761 	if (fd != -1 && fd != STDIN_FILENO)
2762 		close(fd);
2763 	sshkey_free(pubkey);
2764 	sshkey_free(privkey);
2765 	free(hashalg);
2766 	return ret;
2767 }
2768 
2769 static int
2770 sig_verify(const char *signature, const char *sig_namespace,
2771     const char *principal, const char *allowed_keys, const char *revoked_keys,
2772     char * const *opts, size_t nopts)
2773 {
2774 	int r, ret = -1;
2775 	int print_pubkey = 0;
2776 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2777 	struct sshkey *sign_key = NULL;
2778 	char *fp = NULL;
2779 	struct sshkey_sig_details *sig_details = NULL;
2780 	uint64_t verify_time = 0;
2781 
2782 	if (sig_process_opts(opts, nopts, NULL, &verify_time,
2783 	    &print_pubkey) != 0)
2784 		goto done; /* error already logged */
2785 
2786 	memset(&sig_details, 0, sizeof(sig_details));
2787 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2788 		error_r(r, "Couldn't read signature file");
2789 		goto done;
2790 	}
2791 
2792 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2793 		error_fr(r, "sshsig_armor");
2794 		goto done;
2795 	}
2796 	if ((r = sshsig_verify_fd(sigbuf, STDIN_FILENO, sig_namespace,
2797 	    &sign_key, &sig_details)) != 0)
2798 		goto done; /* sshsig_verify() prints error */
2799 
2800 	if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2801 	    SSH_FP_DEFAULT)) == NULL)
2802 		fatal_f("sshkey_fingerprint failed");
2803 	debug("Valid (unverified) signature from key %s", fp);
2804 	if (sig_details != NULL) {
2805 		debug2_f("signature details: counter = %u, flags = 0x%02x",
2806 		    sig_details->sk_counter, sig_details->sk_flags);
2807 	}
2808 	free(fp);
2809 	fp = NULL;
2810 
2811 	if (revoked_keys != NULL) {
2812 		if ((r = sshkey_check_revoked(sign_key, revoked_keys)) != 0) {
2813 			debug3_fr(r, "sshkey_check_revoked");
2814 			goto done;
2815 		}
2816 	}
2817 
2818 	if (allowed_keys != NULL && (r = sshsig_check_allowed_keys(allowed_keys,
2819 	    sign_key, principal, sig_namespace, verify_time)) != 0) {
2820 		debug3_fr(r, "sshsig_check_allowed_keys");
2821 		goto done;
2822 	}
2823 	/* success */
2824 	ret = 0;
2825 done:
2826 	if (!quiet) {
2827 		if (ret == 0) {
2828 			if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2829 			    SSH_FP_DEFAULT)) == NULL)
2830 				fatal_f("sshkey_fingerprint failed");
2831 			if (principal == NULL) {
2832 				printf("Good \"%s\" signature with %s key %s\n",
2833 				    sig_namespace, sshkey_type(sign_key), fp);
2834 
2835 			} else {
2836 				printf("Good \"%s\" signature for %s with %s key %s\n",
2837 				    sig_namespace, principal,
2838 				    sshkey_type(sign_key), fp);
2839 			}
2840 		} else {
2841 			printf("Could not verify signature.\n");
2842 		}
2843 	}
2844 	/* Print the signature key if requested */
2845 	if (ret == 0 && print_pubkey && sign_key != NULL) {
2846 		if ((r = sshkey_write(sign_key, stdout)) == 0)
2847 			fputc('\n', stdout);
2848 		else {
2849 			error_r(r, "Could not print public key.\n");
2850 			ret = -1;
2851 		}
2852 	}
2853 	sshbuf_free(sigbuf);
2854 	sshbuf_free(abuf);
2855 	sshkey_free(sign_key);
2856 	sshkey_sig_details_free(sig_details);
2857 	free(fp);
2858 	return ret;
2859 }
2860 
2861 static int
2862 sig_find_principals(const char *signature, const char *allowed_keys,
2863     char * const *opts, size_t nopts)
2864 {
2865 	int r, ret = -1;
2866 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2867 	struct sshkey *sign_key = NULL;
2868 	char *principals = NULL, *cp, *tmp;
2869 	uint64_t verify_time = 0;
2870 
2871 	if (sig_process_opts(opts, nopts, NULL, &verify_time, NULL) != 0)
2872 		goto done; /* error already logged */
2873 
2874 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2875 		error_r(r, "Couldn't read signature file");
2876 		goto done;
2877 	}
2878 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2879 		error_fr(r, "sshsig_armor");
2880 		goto done;
2881 	}
2882 	if ((r = sshsig_get_pubkey(sigbuf, &sign_key)) != 0) {
2883 		error_fr(r, "sshsig_get_pubkey");
2884 		goto done;
2885 	}
2886 	if ((r = sshsig_find_principals(allowed_keys, sign_key,
2887 	    verify_time, &principals)) != 0) {
2888 		if (r != SSH_ERR_KEY_NOT_FOUND)
2889 			error_fr(r, "sshsig_find_principal");
2890 		goto done;
2891 	}
2892 	ret = 0;
2893 done:
2894 	if (ret == 0 ) {
2895 		/* Emit matching principals one per line */
2896 		tmp = principals;
2897 		while ((cp = strsep(&tmp, ",")) != NULL && *cp != '\0')
2898 			puts(cp);
2899 	} else {
2900 		fprintf(stderr, "No principal matched.\n");
2901 	}
2902 	sshbuf_free(sigbuf);
2903 	sshbuf_free(abuf);
2904 	sshkey_free(sign_key);
2905 	free(principals);
2906 	return ret;
2907 }
2908 
2909 static int
2910 sig_match_principals(const char *allowed_keys, char *principal,
2911 	char * const *opts, size_t nopts)
2912 {
2913 	int r;
2914 	char **principals = NULL;
2915 	size_t i, nprincipals = 0;
2916 
2917 	if ((r = sig_process_opts(opts, nopts, NULL, NULL, NULL)) != 0)
2918 		return r; /* error already logged */
2919 
2920 	if ((r = sshsig_match_principals(allowed_keys, principal,
2921 	    &principals, &nprincipals)) != 0) {
2922 		debug_f("match: %s", ssh_err(r));
2923 		fprintf(stderr, "No principal matched.\n");
2924 		return r;
2925 	}
2926 	for (i = 0; i < nprincipals; i++) {
2927 		printf("%s\n", principals[i]);
2928 		free(principals[i]);
2929 	}
2930 	free(principals);
2931 
2932 	return 0;
2933 }
2934 
2935 static void
2936 do_moduli_gen(const char *out_file, char **opts, size_t nopts)
2937 {
2938 #ifdef WITH_OPENSSL
2939 	/* Moduli generation/screening */
2940 	u_int32_t memory = 0;
2941 	BIGNUM *start = NULL;
2942 	int moduli_bits = 0;
2943 	FILE *out;
2944 	size_t i;
2945 	const char *errstr;
2946 
2947 	/* Parse options */
2948 	for (i = 0; i < nopts; i++) {
2949 		if (strncmp(opts[i], "memory=", 7) == 0) {
2950 			memory = (u_int32_t)strtonum(opts[i]+7, 1,
2951 			    UINT_MAX, &errstr);
2952 			if (errstr) {
2953 				fatal("Memory limit is %s: %s",
2954 				    errstr, opts[i]+7);
2955 			}
2956 		} else if (strncmp(opts[i], "start=", 6) == 0) {
2957 			/* XXX - also compare length against bits */
2958 			if (BN_hex2bn(&start, opts[i]+6) == 0)
2959 				fatal("Invalid start point.");
2960 		} else if (strncmp(opts[i], "bits=", 5) == 0) {
2961 			moduli_bits = (int)strtonum(opts[i]+5, 1,
2962 			    INT_MAX, &errstr);
2963 			if (errstr) {
2964 				fatal("Invalid number: %s (%s)",
2965 					opts[i]+12, errstr);
2966 			}
2967 		} else {
2968 			fatal("Option \"%s\" is unsupported for moduli "
2969 			    "generation", opts[i]);
2970 		}
2971 	}
2972 
2973 	if ((out = fopen(out_file, "w")) == NULL) {
2974 		fatal("Couldn't open modulus candidate file \"%s\": %s",
2975 		    out_file, strerror(errno));
2976 	}
2977 	setvbuf(out, NULL, _IOLBF, 0);
2978 
2979 	if (moduli_bits == 0)
2980 		moduli_bits = DEFAULT_BITS;
2981 	if (gen_candidates(out, memory, moduli_bits, start) != 0)
2982 		fatal("modulus candidate generation failed");
2983 #else /* WITH_OPENSSL */
2984 	fatal("Moduli generation is not supported");
2985 #endif /* WITH_OPENSSL */
2986 }
2987 
2988 static void
2989 do_moduli_screen(const char *out_file, char **opts, size_t nopts)
2990 {
2991 #ifdef WITH_OPENSSL
2992 	/* Moduli generation/screening */
2993 	char *checkpoint = NULL;
2994 	u_int32_t generator_wanted = 0;
2995 	unsigned long start_lineno = 0, lines_to_process = 0;
2996 	int prime_tests = 0;
2997 	FILE *out, *in = stdin;
2998 	size_t i;
2999 	const char *errstr;
3000 
3001 	/* Parse options */
3002 	for (i = 0; i < nopts; i++) {
3003 		if (strncmp(opts[i], "lines=", 6) == 0) {
3004 			lines_to_process = strtoul(opts[i]+6, NULL, 10);
3005 		} else if (strncmp(opts[i], "start-line=", 11) == 0) {
3006 			start_lineno = strtoul(opts[i]+11, NULL, 10);
3007 		} else if (strncmp(opts[i], "checkpoint=", 11) == 0) {
3008 			checkpoint = xstrdup(opts[i]+11);
3009 		} else if (strncmp(opts[i], "generator=", 10) == 0) {
3010 			generator_wanted = (u_int32_t)strtonum(
3011 			    opts[i]+10, 1, UINT_MAX, &errstr);
3012 			if (errstr != NULL) {
3013 				fatal("Generator invalid: %s (%s)",
3014 				    opts[i]+10, errstr);
3015 			}
3016 		} else if (strncmp(opts[i], "prime-tests=", 12) == 0) {
3017 			prime_tests = (int)strtonum(opts[i]+12, 1,
3018 			    INT_MAX, &errstr);
3019 			if (errstr) {
3020 				fatal("Invalid number: %s (%s)",
3021 					opts[i]+12, errstr);
3022 			}
3023 		} else {
3024 			fatal("Option \"%s\" is unsupported for moduli "
3025 			    "screening", opts[i]);
3026 		}
3027 	}
3028 
3029 	if (have_identity && strcmp(identity_file, "-") != 0) {
3030 		if ((in = fopen(identity_file, "r")) == NULL) {
3031 			fatal("Couldn't open modulus candidate "
3032 			    "file \"%s\": %s", identity_file,
3033 			    strerror(errno));
3034 		}
3035 	}
3036 
3037 	if ((out = fopen(out_file, "a")) == NULL) {
3038 		fatal("Couldn't open moduli file \"%s\": %s",
3039 		    out_file, strerror(errno));
3040 	}
3041 	setvbuf(out, NULL, _IOLBF, 0);
3042 	if (prime_test(in, out, prime_tests == 0 ? 100 : prime_tests,
3043 	    generator_wanted, checkpoint,
3044 	    start_lineno, lines_to_process) != 0)
3045 		fatal("modulus screening failed");
3046 #else /* WITH_OPENSSL */
3047 	fatal("Moduli screening is not supported");
3048 #endif /* WITH_OPENSSL */
3049 }
3050 
3051 /* Read and confirm a passphrase */
3052 static char *
3053 read_check_passphrase(const char *prompt1, const char *prompt2,
3054     const char *retry_prompt)
3055 {
3056 	char *passphrase1, *passphrase2;
3057 
3058 	for (;;) {
3059 		passphrase1 = read_passphrase(prompt1, RP_ALLOW_STDIN);
3060 		passphrase2 = read_passphrase(prompt2, RP_ALLOW_STDIN);
3061 		if (strcmp(passphrase1, passphrase2) == 0) {
3062 			freezero(passphrase2, strlen(passphrase2));
3063 			return passphrase1;
3064 		}
3065 		/* The passphrases do not match. Clear them and retry. */
3066 		freezero(passphrase1, strlen(passphrase1));
3067 		freezero(passphrase2, strlen(passphrase2));
3068 		fputs(retry_prompt, stdout);
3069 		fputc('\n', stdout);
3070 		fflush(stdout);
3071 	}
3072 	/* NOTREACHED */
3073 	return NULL;
3074 }
3075 
3076 static char *
3077 private_key_passphrase(void)
3078 {
3079 	if (identity_passphrase)
3080 		return xstrdup(identity_passphrase);
3081 	if (identity_new_passphrase)
3082 		return xstrdup(identity_new_passphrase);
3083 
3084 	return read_check_passphrase(
3085 	    "Enter passphrase (empty for no passphrase): ",
3086 	    "Enter same passphrase again: ",
3087 	    "Passphrases do not match.  Try again.");
3088 }
3089 
3090 static char *
3091 sk_suffix(const char *application, const uint8_t *user, size_t userlen)
3092 {
3093 	char *ret, *cp;
3094 	size_t slen, i;
3095 
3096 	/* Trim off URL-like preamble */
3097 	if (strncmp(application, "ssh://", 6) == 0)
3098 		ret =  xstrdup(application + 6);
3099 	else if (strncmp(application, "ssh:", 4) == 0)
3100 		ret =  xstrdup(application + 4);
3101 	else
3102 		ret = xstrdup(application);
3103 
3104 	/* Count trailing zeros in user */
3105 	for (i = 0; i < userlen; i++) {
3106 		if (user[userlen - i - 1] != 0)
3107 			break;
3108 	}
3109 	if (i >= userlen)
3110 		return ret; /* user-id was default all-zeros */
3111 
3112 	/* Append user-id, escaping non-UTF-8 characters */
3113 	slen = userlen - i;
3114 	if (asmprintf(&cp, INT_MAX, NULL, "%.*s", (int)slen, user) == -1)
3115 		fatal_f("asmprintf failed");
3116 	/* Don't emit a user-id that contains path or control characters */
3117 	if (strchr(cp, '/') != NULL || strstr(cp, "..") != NULL ||
3118 	    strchr(cp, '\\') != NULL) {
3119 		free(cp);
3120 		cp = tohex(user, slen);
3121 	}
3122 	xextendf(&ret, "_", "%s", cp);
3123 	free(cp);
3124 	return ret;
3125 }
3126 
3127 static int
3128 do_download_sk(const char *skprovider, const char *device)
3129 {
3130 	struct sshsk_resident_key **srks;
3131 	size_t nsrks, i;
3132 	int r, ret = -1;
3133 	char *fp, *pin = NULL, *pass = NULL, *path, *pubpath;
3134 	const char *ext;
3135 	struct sshkey *key;
3136 
3137 	if (skprovider == NULL)
3138 		fatal("Cannot download keys without provider");
3139 
3140 	pin = read_passphrase("Enter PIN for authenticator: ", RP_ALLOW_STDIN);
3141 	if (!quiet) {
3142 		printf("You may need to touch your authenticator "
3143 		    "to authorize key download.\n");
3144 	}
3145 	if ((r = sshsk_load_resident(skprovider, device, pin, 0,
3146 	    &srks, &nsrks)) != 0) {
3147 		if (pin != NULL)
3148 			freezero(pin, strlen(pin));
3149 		error_r(r, "Unable to load resident keys");
3150 		return -1;
3151 	}
3152 	if (nsrks == 0)
3153 		logit("No keys to download");
3154 	if (pin != NULL)
3155 		freezero(pin, strlen(pin));
3156 
3157 	for (i = 0; i < nsrks; i++) {
3158 		key = srks[i]->key;
3159 		if (key->type != KEY_ECDSA_SK && key->type != KEY_ED25519_SK) {
3160 			error("Unsupported key type %s (%d)",
3161 			    sshkey_type(key), key->type);
3162 			continue;
3163 		}
3164 		if ((fp = sshkey_fingerprint(key, fingerprint_hash,
3165 		    SSH_FP_DEFAULT)) == NULL)
3166 			fatal_f("sshkey_fingerprint failed");
3167 		debug_f("key %zu: %s %s %s (flags 0x%02x)", i,
3168 		    sshkey_type(key), fp, key->sk_application, key->sk_flags);
3169 		ext = sk_suffix(key->sk_application,
3170 		    srks[i]->user_id, srks[i]->user_id_len);
3171 		xasprintf(&path, "id_%s_rk%s%s",
3172 		    key->type == KEY_ECDSA_SK ? "ecdsa_sk" : "ed25519_sk",
3173 		    *ext == '\0' ? "" : "_", ext);
3174 
3175 		/* If the file already exists, ask the user to confirm. */
3176 		if (!confirm_overwrite(path)) {
3177 			free(path);
3178 			break;
3179 		}
3180 
3181 		/* Save the key with the application string as the comment */
3182 		if (pass == NULL)
3183 			pass = private_key_passphrase();
3184 		if ((r = sshkey_save_private(key, path, pass,
3185 		    key->sk_application, private_key_format,
3186 		    openssh_format_cipher, rounds)) != 0) {
3187 			error_r(r, "Saving key \"%s\" failed", path);
3188 			free(path);
3189 			break;
3190 		}
3191 		if (!quiet) {
3192 			printf("Saved %s key%s%s to %s\n", sshkey_type(key),
3193 			    *ext != '\0' ? " " : "",
3194 			    *ext != '\0' ? key->sk_application : "",
3195 			    path);
3196 		}
3197 
3198 		/* Save public key too */
3199 		xasprintf(&pubpath, "%s.pub", path);
3200 		free(path);
3201 		if ((r = sshkey_save_public(key, pubpath,
3202 		    key->sk_application)) != 0) {
3203 			error_r(r, "Saving public key \"%s\" failed", pubpath);
3204 			free(pubpath);
3205 			break;
3206 		}
3207 		free(pubpath);
3208 	}
3209 
3210 	if (i >= nsrks)
3211 		ret = 0; /* success */
3212 	if (pass != NULL)
3213 		freezero(pass, strlen(pass));
3214 	sshsk_free_resident_keys(srks, nsrks);
3215 	return ret;
3216 }
3217 
3218 static void
3219 save_attestation(struct sshbuf *attest, const char *path)
3220 {
3221 	mode_t omask;
3222 	int r;
3223 
3224 	if (path == NULL)
3225 		return; /* nothing to do */
3226 	if (attest == NULL || sshbuf_len(attest) == 0)
3227 		fatal("Enrollment did not return attestation data");
3228 	omask = umask(077);
3229 	r = sshbuf_write_file(path, attest);
3230 	umask(omask);
3231 	if (r != 0)
3232 		fatal_r(r, "Unable to write attestation data \"%s\"", path);
3233 	if (!quiet)
3234 		printf("Your FIDO attestation certificate has been saved in "
3235 		    "%s\n", path);
3236 }
3237 
3238 static int
3239 confirm_sk_overwrite(const char *application, const char *user)
3240 {
3241 	char yesno[3];
3242 
3243 	printf("A resident key scoped to '%s' with user id '%s' already "
3244 	    "exists.\n", application == NULL ? "ssh:" : application,
3245 	    user == NULL ? "null" : user);
3246 	printf("Overwrite key in token (y/n)? ");
3247 	fflush(stdout);
3248 	if (fgets(yesno, sizeof(yesno), stdin) == NULL)
3249 		return 0;
3250 	if (yesno[0] != 'y' && yesno[0] != 'Y')
3251 		return 0;
3252 	return 1;
3253 }
3254 
3255 static void
3256 usage(void)
3257 {
3258 	fprintf(stderr,
3259 	    "usage: ssh-keygen [-q] [-a rounds] [-b bits] [-C comment] [-f output_keyfile]\n"
3260 	    "                  [-m format] [-N new_passphrase] [-O option]\n"
3261 	    "                  [-t dsa | ecdsa | ecdsa-sk | ed25519 | ed25519-sk | rsa]\n"
3262 	    "                  [-w provider] [-Z cipher]\n"
3263 	    "       ssh-keygen -p [-a rounds] [-f keyfile] [-m format] [-N new_passphrase]\n"
3264 	    "                   [-P old_passphrase] [-Z cipher]\n"
3265 #ifdef WITH_OPENSSL
3266 	    "       ssh-keygen -i [-f input_keyfile] [-m key_format]\n"
3267 	    "       ssh-keygen -e [-f input_keyfile] [-m key_format]\n"
3268 #endif
3269 	    "       ssh-keygen -y [-f input_keyfile]\n"
3270 	    "       ssh-keygen -c [-a rounds] [-C comment] [-f keyfile] [-P passphrase]\n"
3271 	    "       ssh-keygen -l [-v] [-E fingerprint_hash] [-f input_keyfile]\n"
3272 	    "       ssh-keygen -B [-f input_keyfile]\n");
3273 #ifdef ENABLE_PKCS11
3274 	fprintf(stderr,
3275 	    "       ssh-keygen -D pkcs11\n");
3276 #endif
3277 	fprintf(stderr,
3278 	    "       ssh-keygen -F hostname [-lv] [-f known_hosts_file]\n"
3279 	    "       ssh-keygen -H [-f known_hosts_file]\n"
3280 	    "       ssh-keygen -K [-a rounds] [-w provider]\n"
3281 	    "       ssh-keygen -R hostname [-f known_hosts_file]\n"
3282 	    "       ssh-keygen -r hostname [-g] [-f input_keyfile]\n"
3283 #ifdef WITH_OPENSSL
3284 	    "       ssh-keygen -M generate [-O option] output_file\n"
3285 	    "       ssh-keygen -M screen [-f input_file] [-O option] output_file\n"
3286 #endif
3287 	    "       ssh-keygen -I certificate_identity -s ca_key [-hU] [-D pkcs11_provider]\n"
3288 	    "                  [-n principals] [-O option] [-V validity_interval]\n"
3289 	    "                  [-z serial_number] file ...\n"
3290 	    "       ssh-keygen -L [-f input_keyfile]\n"
3291 	    "       ssh-keygen -A [-a rounds] [-f prefix_path]\n"
3292 	    "       ssh-keygen -k -f krl_file [-u] [-s ca_public] [-z version_number]\n"
3293 	    "                  file ...\n"
3294 	    "       ssh-keygen -Q [-l] -f krl_file [file ...]\n"
3295 	    "       ssh-keygen -Y find-principals -s signature_file -f allowed_signers_file\n"
3296 	    "       ssh-keygen -Y match-principals -I signer_identity -f allowed_signers_file\n"
3297 	    "       ssh-keygen -Y check-novalidate -n namespace -s signature_file\n"
3298 	    "       ssh-keygen -Y sign -f key_file -n namespace file [-O option] ...\n"
3299 	    "       ssh-keygen -Y verify -f allowed_signers_file -I signer_identity\n"
3300 	    "                  -n namespace -s signature_file [-r krl_file] [-O option]\n");
3301 	exit(1);
3302 }
3303 
3304 /*
3305  * Main program for key management.
3306  */
3307 int
3308 main(int argc, char **argv)
3309 {
3310 	char comment[1024], *passphrase = NULL;
3311 	char *rr_hostname = NULL, *ep, *fp, *ra;
3312 	struct sshkey *private, *public;
3313 	struct passwd *pw;
3314 	int r, opt, type;
3315 	int change_passphrase = 0, change_comment = 0, show_cert = 0;
3316 	int find_host = 0, delete_host = 0, hash_hosts = 0;
3317 	int gen_all_hostkeys = 0, gen_krl = 0, update_krl = 0, check_krl = 0;
3318 	int prefer_agent = 0, convert_to = 0, convert_from = 0;
3319 	int print_public = 0, print_generic = 0, cert_serial_autoinc = 0;
3320 	int do_gen_candidates = 0, do_screen_candidates = 0, download_sk = 0;
3321 	unsigned long long cert_serial = 0;
3322 	char *identity_comment = NULL, *ca_key_path = NULL, **opts = NULL;
3323 	char *sk_application = NULL, *sk_device = NULL, *sk_user = NULL;
3324 	char *sk_attestation_path = NULL;
3325 	struct sshbuf *challenge = NULL, *attest = NULL;
3326 	size_t i, nopts = 0;
3327 	u_int32_t bits = 0;
3328 	uint8_t sk_flags = SSH_SK_USER_PRESENCE_REQD;
3329 	const char *errstr;
3330 	int log_level = SYSLOG_LEVEL_INFO;
3331 	char *sign_op = NULL;
3332 
3333 	extern int optind;
3334 	extern char *optarg;
3335 
3336 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
3337 	sanitise_stdfd();
3338 
3339 	__progname = ssh_get_progname(argv[0]);
3340 
3341 	seed_rng();
3342 
3343 	log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
3344 
3345 	msetlocale();
3346 
3347 	/* we need this for the home * directory.  */
3348 	pw = getpwuid(getuid());
3349 	if (!pw)
3350 		fatal("No user exists for uid %lu", (u_long)getuid());
3351 	pw = pwcopy(pw);
3352 	if (gethostname(hostname, sizeof(hostname)) == -1)
3353 		fatal("gethostname: %s", strerror(errno));
3354 
3355 	sk_provider = getenv("SSH_SK_PROVIDER");
3356 
3357 	/* Remaining characters: dGjJSTWx */
3358 	while ((opt = getopt(argc, argv, "ABHKLQUXceghiklopquvy"
3359 	    "C:D:E:F:I:M:N:O:P:R:V:Y:Z:"
3360 	    "a:b:f:g:m:n:r:s:t:w:z:")) != -1) {
3361 		switch (opt) {
3362 		case 'A':
3363 			gen_all_hostkeys = 1;
3364 			break;
3365 		case 'b':
3366 			bits = (u_int32_t)strtonum(optarg, 1, UINT32_MAX,
3367 			    &errstr);
3368 			if (errstr)
3369 				fatal("Bits has bad value %s (%s)",
3370 					optarg, errstr);
3371 			break;
3372 		case 'E':
3373 			fingerprint_hash = ssh_digest_alg_by_name(optarg);
3374 			if (fingerprint_hash == -1)
3375 				fatal("Invalid hash algorithm \"%s\"", optarg);
3376 			break;
3377 		case 'F':
3378 			find_host = 1;
3379 			rr_hostname = optarg;
3380 			break;
3381 		case 'H':
3382 			hash_hosts = 1;
3383 			break;
3384 		case 'I':
3385 			cert_key_id = optarg;
3386 			break;
3387 		case 'R':
3388 			delete_host = 1;
3389 			rr_hostname = optarg;
3390 			break;
3391 		case 'L':
3392 			show_cert = 1;
3393 			break;
3394 		case 'l':
3395 			print_fingerprint = 1;
3396 			break;
3397 		case 'B':
3398 			print_bubblebabble = 1;
3399 			break;
3400 		case 'm':
3401 			if (strcasecmp(optarg, "RFC4716") == 0 ||
3402 			    strcasecmp(optarg, "ssh2") == 0) {
3403 				convert_format = FMT_RFC4716;
3404 				break;
3405 			}
3406 			if (strcasecmp(optarg, "PKCS8") == 0) {
3407 				convert_format = FMT_PKCS8;
3408 				private_key_format = SSHKEY_PRIVATE_PKCS8;
3409 				break;
3410 			}
3411 			if (strcasecmp(optarg, "PEM") == 0) {
3412 				convert_format = FMT_PEM;
3413 				private_key_format = SSHKEY_PRIVATE_PEM;
3414 				break;
3415 			}
3416 			fatal("Unsupported conversion format \"%s\"", optarg);
3417 		case 'n':
3418 			cert_principals = optarg;
3419 			break;
3420 		case 'o':
3421 			/* no-op; new format is already the default */
3422 			break;
3423 		case 'p':
3424 			change_passphrase = 1;
3425 			break;
3426 		case 'c':
3427 			change_comment = 1;
3428 			break;
3429 		case 'f':
3430 			if (strlcpy(identity_file, optarg,
3431 			    sizeof(identity_file)) >= sizeof(identity_file))
3432 				fatal("Identity filename too long");
3433 			have_identity = 1;
3434 			break;
3435 		case 'g':
3436 			print_generic = 1;
3437 			break;
3438 		case 'K':
3439 			download_sk = 1;
3440 			break;
3441 		case 'P':
3442 			identity_passphrase = optarg;
3443 			break;
3444 		case 'N':
3445 			identity_new_passphrase = optarg;
3446 			break;
3447 		case 'Q':
3448 			check_krl = 1;
3449 			break;
3450 		case 'O':
3451 			opts = xrecallocarray(opts, nopts, nopts + 1,
3452 			    sizeof(*opts));
3453 			opts[nopts++] = xstrdup(optarg);
3454 			break;
3455 		case 'Z':
3456 			openssh_format_cipher = optarg;
3457 			if (cipher_by_name(openssh_format_cipher) == NULL)
3458 				fatal("Invalid OpenSSH-format cipher '%s'",
3459 				    openssh_format_cipher);
3460 			break;
3461 		case 'C':
3462 			identity_comment = optarg;
3463 			break;
3464 		case 'q':
3465 			quiet = 1;
3466 			break;
3467 		case 'e':
3468 			/* export key */
3469 			convert_to = 1;
3470 			break;
3471 		case 'h':
3472 			cert_key_type = SSH2_CERT_TYPE_HOST;
3473 			certflags_flags = 0;
3474 			break;
3475 		case 'k':
3476 			gen_krl = 1;
3477 			break;
3478 		case 'i':
3479 		case 'X':
3480 			/* import key */
3481 			convert_from = 1;
3482 			break;
3483 		case 'y':
3484 			print_public = 1;
3485 			break;
3486 		case 's':
3487 			ca_key_path = optarg;
3488 			break;
3489 		case 't':
3490 			key_type_name = optarg;
3491 			break;
3492 		case 'D':
3493 			pkcs11provider = optarg;
3494 			break;
3495 		case 'U':
3496 			prefer_agent = 1;
3497 			break;
3498 		case 'u':
3499 			update_krl = 1;
3500 			break;
3501 		case 'v':
3502 			if (log_level == SYSLOG_LEVEL_INFO)
3503 				log_level = SYSLOG_LEVEL_DEBUG1;
3504 			else {
3505 				if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
3506 				    log_level < SYSLOG_LEVEL_DEBUG3)
3507 					log_level++;
3508 			}
3509 			break;
3510 		case 'r':
3511 			rr_hostname = optarg;
3512 			break;
3513 		case 'a':
3514 			rounds = (int)strtonum(optarg, 1, INT_MAX, &errstr);
3515 			if (errstr)
3516 				fatal("Invalid number: %s (%s)",
3517 					optarg, errstr);
3518 			break;
3519 		case 'V':
3520 			parse_cert_times(optarg);
3521 			break;
3522 		case 'Y':
3523 			sign_op = optarg;
3524 			break;
3525 		case 'w':
3526 			sk_provider = optarg;
3527 			break;
3528 		case 'z':
3529 			errno = 0;
3530 			if (*optarg == '+') {
3531 				cert_serial_autoinc = 1;
3532 				optarg++;
3533 			}
3534 			cert_serial = strtoull(optarg, &ep, 10);
3535 			if (*optarg < '0' || *optarg > '9' || *ep != '\0' ||
3536 			    (errno == ERANGE && cert_serial == ULLONG_MAX))
3537 				fatal("Invalid serial number \"%s\"", optarg);
3538 			break;
3539 		case 'M':
3540 			if (strcmp(optarg, "generate") == 0)
3541 				do_gen_candidates = 1;
3542 			else if (strcmp(optarg, "screen") == 0)
3543 				do_screen_candidates = 1;
3544 			else
3545 				fatal("Unsupported moduli option %s", optarg);
3546 			break;
3547 		default:
3548 			usage();
3549 		}
3550 	}
3551 
3552 #ifdef ENABLE_SK_INTERNAL
3553 	if (sk_provider == NULL)
3554 		sk_provider = "internal";
3555 #endif
3556 
3557 	/* reinit */
3558 	log_init(argv[0], log_level, SYSLOG_FACILITY_USER, 1);
3559 
3560 	argv += optind;
3561 	argc -= optind;
3562 
3563 	if (sign_op != NULL) {
3564 		if (strncmp(sign_op, "find-principals", 15) == 0) {
3565 			if (ca_key_path == NULL) {
3566 				error("Too few arguments for find-principals:"
3567 				    "missing signature file");
3568 				exit(1);
3569 			}
3570 			if (!have_identity) {
3571 				error("Too few arguments for find-principals:"
3572 				    "missing allowed keys file");
3573 				exit(1);
3574 			}
3575 			return sig_find_principals(ca_key_path, identity_file,
3576 			    opts, nopts);
3577 		} else if (strncmp(sign_op, "match-principals", 16) == 0) {
3578 			if (!have_identity) {
3579 				error("Too few arguments for match-principals:"
3580 				    "missing allowed keys file");
3581 				exit(1);
3582 			}
3583 			if (cert_key_id == NULL) {
3584 				error("Too few arguments for match-principals: "
3585 				    "missing principal ID");
3586 				exit(1);
3587 			}
3588 			return sig_match_principals(identity_file, cert_key_id,
3589 			    opts, nopts);
3590 		} else if (strncmp(sign_op, "sign", 4) == 0) {
3591 			/* NB. cert_principals is actually namespace, via -n */
3592 			if (cert_principals == NULL ||
3593 			    *cert_principals == '\0') {
3594 				error("Too few arguments for sign: "
3595 				    "missing namespace");
3596 				exit(1);
3597 			}
3598 			if (!have_identity) {
3599 				error("Too few arguments for sign: "
3600 				    "missing key");
3601 				exit(1);
3602 			}
3603 			return sig_sign(identity_file, cert_principals,
3604 			    prefer_agent, argc, argv, opts, nopts);
3605 		} else if (strncmp(sign_op, "check-novalidate", 16) == 0) {
3606 			/* NB. cert_principals is actually namespace, via -n */
3607 			if (cert_principals == NULL ||
3608 			    *cert_principals == '\0') {
3609 				error("Too few arguments for check-novalidate: "
3610 				    "missing namespace");
3611 				exit(1);
3612 			}
3613 			if (ca_key_path == NULL) {
3614 				error("Too few arguments for check-novalidate: "
3615 				    "missing signature file");
3616 				exit(1);
3617 			}
3618 			return sig_verify(ca_key_path, cert_principals,
3619 			    NULL, NULL, NULL, opts, nopts);
3620 		} else if (strncmp(sign_op, "verify", 6) == 0) {
3621 			/* NB. cert_principals is actually namespace, via -n */
3622 			if (cert_principals == NULL ||
3623 			    *cert_principals == '\0') {
3624 				error("Too few arguments for verify: "
3625 				    "missing namespace");
3626 				exit(1);
3627 			}
3628 			if (ca_key_path == NULL) {
3629 				error("Too few arguments for verify: "
3630 				    "missing signature file");
3631 				exit(1);
3632 			}
3633 			if (!have_identity) {
3634 				error("Too few arguments for sign: "
3635 				    "missing allowed keys file");
3636 				exit(1);
3637 			}
3638 			if (cert_key_id == NULL) {
3639 				error("Too few arguments for verify: "
3640 				    "missing principal identity");
3641 				exit(1);
3642 			}
3643 			return sig_verify(ca_key_path, cert_principals,
3644 			    cert_key_id, identity_file, rr_hostname,
3645 			    opts, nopts);
3646 		}
3647 		error("Unsupported operation for -Y: \"%s\"", sign_op);
3648 		usage();
3649 		/* NOTREACHED */
3650 	}
3651 
3652 	if (ca_key_path != NULL) {
3653 		if (argc < 1 && !gen_krl) {
3654 			error("Too few arguments.");
3655 			usage();
3656 		}
3657 	} else if (argc > 0 && !gen_krl && !check_krl &&
3658 	    !do_gen_candidates && !do_screen_candidates) {
3659 		error("Too many arguments.");
3660 		usage();
3661 	}
3662 	if (change_passphrase && change_comment) {
3663 		error("Can only have one of -p and -c.");
3664 		usage();
3665 	}
3666 	if (print_fingerprint && (delete_host || hash_hosts)) {
3667 		error("Cannot use -l with -H or -R.");
3668 		usage();
3669 	}
3670 	if (gen_krl) {
3671 		do_gen_krl(pw, update_krl, ca_key_path,
3672 		    cert_serial, identity_comment, argc, argv);
3673 		return (0);
3674 	}
3675 	if (check_krl) {
3676 		do_check_krl(pw, print_fingerprint, argc, argv);
3677 		return (0);
3678 	}
3679 	if (ca_key_path != NULL) {
3680 		if (cert_key_id == NULL)
3681 			fatal("Must specify key id (-I) when certifying");
3682 		for (i = 0; i < nopts; i++)
3683 			add_cert_option(opts[i]);
3684 		do_ca_sign(pw, ca_key_path, prefer_agent,
3685 		    cert_serial, cert_serial_autoinc, argc, argv);
3686 	}
3687 	if (show_cert)
3688 		do_show_cert(pw);
3689 	if (delete_host || hash_hosts || find_host) {
3690 		do_known_hosts(pw, rr_hostname, find_host,
3691 		    delete_host, hash_hosts);
3692 	}
3693 	if (pkcs11provider != NULL)
3694 		do_download(pw);
3695 	if (download_sk) {
3696 		for (i = 0; i < nopts; i++) {
3697 			if (strncasecmp(opts[i], "device=", 7) == 0) {
3698 				sk_device = xstrdup(opts[i] + 7);
3699 			} else {
3700 				fatal("Option \"%s\" is unsupported for "
3701 				    "FIDO authenticator download", opts[i]);
3702 			}
3703 		}
3704 		return do_download_sk(sk_provider, sk_device);
3705 	}
3706 	if (print_fingerprint || print_bubblebabble)
3707 		do_fingerprint(pw);
3708 	if (change_passphrase)
3709 		do_change_passphrase(pw);
3710 	if (change_comment)
3711 		do_change_comment(pw, identity_comment);
3712 #ifdef WITH_OPENSSL
3713 	if (convert_to)
3714 		do_convert_to(pw);
3715 	if (convert_from)
3716 		do_convert_from(pw);
3717 #else /* WITH_OPENSSL */
3718 	if (convert_to || convert_from)
3719 		fatal("key conversion disabled at compile time");
3720 #endif /* WITH_OPENSSL */
3721 	if (print_public)
3722 		do_print_public(pw);
3723 	if (rr_hostname != NULL) {
3724 		unsigned int n = 0;
3725 
3726 		if (have_identity) {
3727 			n = do_print_resource_record(pw, identity_file,
3728 			    rr_hostname, print_generic);
3729 			if (n == 0)
3730 				fatal("%s: %s", identity_file, strerror(errno));
3731 			exit(0);
3732 		} else {
3733 
3734 			n += do_print_resource_record(pw,
3735 			    _PATH_HOST_RSA_KEY_FILE, rr_hostname,
3736 			    print_generic);
3737 			n += do_print_resource_record(pw,
3738 			    _PATH_HOST_DSA_KEY_FILE, rr_hostname,
3739 			    print_generic);
3740 			n += do_print_resource_record(pw,
3741 			    _PATH_HOST_ECDSA_KEY_FILE, rr_hostname,
3742 			    print_generic);
3743 			n += do_print_resource_record(pw,
3744 			    _PATH_HOST_ED25519_KEY_FILE, rr_hostname,
3745 			    print_generic);
3746 			n += do_print_resource_record(pw,
3747 			    _PATH_HOST_XMSS_KEY_FILE, rr_hostname,
3748 			    print_generic);
3749 			if (n == 0)
3750 				fatal("no keys found.");
3751 			exit(0);
3752 		}
3753 	}
3754 
3755 	if (do_gen_candidates || do_screen_candidates) {
3756 		if (argc <= 0)
3757 			fatal("No output file specified");
3758 		else if (argc > 1)
3759 			fatal("Too many output files specified");
3760 	}
3761 	if (do_gen_candidates) {
3762 		do_moduli_gen(argv[0], opts, nopts);
3763 		return 0;
3764 	}
3765 	if (do_screen_candidates) {
3766 		do_moduli_screen(argv[0], opts, nopts);
3767 		return 0;
3768 	}
3769 
3770 	if (gen_all_hostkeys) {
3771 		do_gen_all_hostkeys(pw);
3772 		return (0);
3773 	}
3774 
3775 	if (key_type_name == NULL)
3776 		key_type_name = DEFAULT_KEY_TYPE_NAME;
3777 
3778 	type = sshkey_type_from_name(key_type_name);
3779 	type_bits_valid(type, key_type_name, &bits);
3780 
3781 	if (!quiet)
3782 		printf("Generating public/private %s key pair.\n",
3783 		    key_type_name);
3784 	switch (type) {
3785 	case KEY_ECDSA_SK:
3786 	case KEY_ED25519_SK:
3787 		for (i = 0; i < nopts; i++) {
3788 			if (strcasecmp(opts[i], "no-touch-required") == 0) {
3789 				sk_flags &= ~SSH_SK_USER_PRESENCE_REQD;
3790 			} else if (strcasecmp(opts[i], "verify-required") == 0) {
3791 				sk_flags |= SSH_SK_USER_VERIFICATION_REQD;
3792 			} else if (strcasecmp(opts[i], "resident") == 0) {
3793 				sk_flags |= SSH_SK_RESIDENT_KEY;
3794 			} else if (strncasecmp(opts[i], "device=", 7) == 0) {
3795 				sk_device = xstrdup(opts[i] + 7);
3796 			} else if (strncasecmp(opts[i], "user=", 5) == 0) {
3797 				sk_user = xstrdup(opts[i] + 5);
3798 			} else if (strncasecmp(opts[i], "challenge=", 10) == 0) {
3799 				if ((r = sshbuf_load_file(opts[i] + 10,
3800 				    &challenge)) != 0) {
3801 					fatal_r(r, "Unable to load FIDO "
3802 					    "enrollment challenge \"%s\"",
3803 					    opts[i] + 10);
3804 				}
3805 			} else if (strncasecmp(opts[i],
3806 			    "write-attestation=", 18) == 0) {
3807 				sk_attestation_path = opts[i] + 18;
3808 			} else if (strncasecmp(opts[i],
3809 			    "application=", 12) == 0) {
3810 				sk_application = xstrdup(opts[i] + 12);
3811 				if (strncmp(sk_application, "ssh:", 4) != 0) {
3812 					fatal("FIDO application string must "
3813 					    "begin with \"ssh:\"");
3814 				}
3815 			} else {
3816 				fatal("Option \"%s\" is unsupported for "
3817 				    "FIDO authenticator enrollment", opts[i]);
3818 			}
3819 		}
3820 		if ((attest = sshbuf_new()) == NULL)
3821 			fatal("sshbuf_new failed");
3822 		r = 0;
3823 		for (i = 0 ;;) {
3824 			if (!quiet) {
3825 				printf("You may need to touch your "
3826 				    "authenticator%s to authorize key "
3827 				    "generation.\n",
3828 				    r == 0 ? "" : " again");
3829 			}
3830 			fflush(stdout);
3831 			r = sshsk_enroll(type, sk_provider, sk_device,
3832 			    sk_application == NULL ? "ssh:" : sk_application,
3833 			    sk_user, sk_flags, passphrase, challenge,
3834 			    &private, attest);
3835 			if (r == 0)
3836 				break;
3837 			if (r == SSH_ERR_KEY_BAD_PERMISSIONS &&
3838 			    (sk_flags & SSH_SK_RESIDENT_KEY) != 0 &&
3839 			    (sk_flags & SSH_SK_FORCE_OPERATION) == 0 &&
3840 			    confirm_sk_overwrite(sk_application, sk_user)) {
3841 				sk_flags |= SSH_SK_FORCE_OPERATION;
3842 				continue;
3843 			}
3844 			if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
3845 				fatal_r(r, "Key enrollment failed");
3846 			else if (passphrase != NULL) {
3847 				error("PIN incorrect");
3848 				freezero(passphrase, strlen(passphrase));
3849 				passphrase = NULL;
3850 			}
3851 			if (++i >= 3)
3852 				fatal("Too many incorrect PINs");
3853 			passphrase = read_passphrase("Enter PIN for "
3854 			    "authenticator: ", RP_ALLOW_STDIN);
3855 		}
3856 		if (passphrase != NULL) {
3857 			freezero(passphrase, strlen(passphrase));
3858 			passphrase = NULL;
3859 		}
3860 		break;
3861 	default:
3862 		if ((r = sshkey_generate(type, bits, &private)) != 0)
3863 			fatal("sshkey_generate failed");
3864 		break;
3865 	}
3866 	if ((r = sshkey_from_private(private, &public)) != 0)
3867 		fatal_r(r, "sshkey_from_private");
3868 
3869 	if (!have_identity)
3870 		ask_filename(pw, "Enter file in which to save the key");
3871 
3872 	/* Create ~/.ssh directory if it doesn't already exist. */
3873 	hostfile_create_user_ssh_dir(identity_file, !quiet);
3874 
3875 	/* If the file already exists, ask the user to confirm. */
3876 	if (!confirm_overwrite(identity_file))
3877 		exit(1);
3878 
3879 	/* Determine the passphrase for the private key */
3880 	passphrase = private_key_passphrase();
3881 	if (identity_comment) {
3882 		strlcpy(comment, identity_comment, sizeof(comment));
3883 	} else {
3884 		/* Create default comment field for the passphrase. */
3885 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
3886 	}
3887 
3888 	/* Save the key with the given passphrase and comment. */
3889 	if ((r = sshkey_save_private(private, identity_file, passphrase,
3890 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
3891 		error_r(r, "Saving key \"%s\" failed", identity_file);
3892 		freezero(passphrase, strlen(passphrase));
3893 		exit(1);
3894 	}
3895 	freezero(passphrase, strlen(passphrase));
3896 	sshkey_free(private);
3897 
3898 	if (!quiet) {
3899 		printf("Your identification has been saved in %s\n",
3900 		    identity_file);
3901 	}
3902 
3903 	strlcat(identity_file, ".pub", sizeof(identity_file));
3904 	if ((r = sshkey_save_public(public, identity_file, comment)) != 0)
3905 		fatal_r(r, "Unable to save public key to %s", identity_file);
3906 
3907 	if (!quiet) {
3908 		fp = sshkey_fingerprint(public, fingerprint_hash,
3909 		    SSH_FP_DEFAULT);
3910 		ra = sshkey_fingerprint(public, fingerprint_hash,
3911 		    SSH_FP_RANDOMART);
3912 		if (fp == NULL || ra == NULL)
3913 			fatal("sshkey_fingerprint failed");
3914 		printf("Your public key has been saved in %s\n",
3915 		    identity_file);
3916 		printf("The key fingerprint is:\n");
3917 		printf("%s %s\n", fp, comment);
3918 		printf("The key's randomart image is:\n");
3919 		printf("%s\n", ra);
3920 		free(ra);
3921 		free(fp);
3922 	}
3923 
3924 	if (sk_attestation_path != NULL)
3925 		save_attestation(attest, sk_attestation_path);
3926 
3927 	sshbuf_free(attest);
3928 	sshkey_free(public);
3929 
3930 	exit(0);
3931 }
3932