xref: /freebsd/crypto/openssh/ssh-keygen.c (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1 /* $OpenBSD: ssh-keygen.c,v 1.466 2023/03/08 00:05:37 djm Exp $ */
2 /*
3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
4  * Copyright (c) 1994 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5  *                    All rights reserved
6  * Identity and host key generation and maintenance.
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  */
14 
15 #include "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 	const char *alg = NULL;
480 	u_char e1, e2, e3, *sig = NULL, data[] = "abcde12345";
481 	int r, rlen, ktype;
482 	u_int magic, i1, i2, i3, i4;
483 	size_t slen;
484 	u_long e;
485 	BIGNUM *dsa_p = NULL, *dsa_q = NULL, *dsa_g = NULL;
486 	BIGNUM *dsa_pub_key = NULL, *dsa_priv_key = NULL;
487 	BIGNUM *rsa_n = NULL, *rsa_e = NULL, *rsa_d = NULL;
488 	BIGNUM *rsa_p = NULL, *rsa_q = NULL, *rsa_iqmp = NULL;
489 
490 	if ((r = sshbuf_get_u32(b, &magic)) != 0)
491 		fatal_fr(r, "parse magic");
492 
493 	if (magic != SSH_COM_PRIVATE_KEY_MAGIC) {
494 		error("bad magic 0x%x != 0x%x", magic,
495 		    SSH_COM_PRIVATE_KEY_MAGIC);
496 		return NULL;
497 	}
498 	if ((r = sshbuf_get_u32(b, &i1)) != 0 ||
499 	    (r = sshbuf_get_cstring(b, &type, NULL)) != 0 ||
500 	    (r = sshbuf_get_cstring(b, &cipher, NULL)) != 0 ||
501 	    (r = sshbuf_get_u32(b, &i2)) != 0 ||
502 	    (r = sshbuf_get_u32(b, &i3)) != 0 ||
503 	    (r = sshbuf_get_u32(b, &i4)) != 0)
504 		fatal_fr(r, "parse");
505 	debug("ignore (%d %d %d %d)", i1, i2, i3, i4);
506 	if (strcmp(cipher, "none") != 0) {
507 		error("unsupported cipher %s", cipher);
508 		free(cipher);
509 		free(type);
510 		return NULL;
511 	}
512 	free(cipher);
513 
514 	if (strstr(type, "dsa")) {
515 		ktype = KEY_DSA;
516 	} else if (strstr(type, "rsa")) {
517 		ktype = KEY_RSA;
518 	} else {
519 		free(type);
520 		return NULL;
521 	}
522 	if ((key = sshkey_new(ktype)) == NULL)
523 		fatal("sshkey_new failed");
524 	free(type);
525 
526 	switch (key->type) {
527 	case KEY_DSA:
528 		if ((dsa_p = BN_new()) == NULL ||
529 		    (dsa_q = BN_new()) == NULL ||
530 		    (dsa_g = BN_new()) == NULL ||
531 		    (dsa_pub_key = BN_new()) == NULL ||
532 		    (dsa_priv_key = BN_new()) == NULL)
533 			fatal_f("BN_new");
534 		buffer_get_bignum_bits(b, dsa_p);
535 		buffer_get_bignum_bits(b, dsa_g);
536 		buffer_get_bignum_bits(b, dsa_q);
537 		buffer_get_bignum_bits(b, dsa_pub_key);
538 		buffer_get_bignum_bits(b, dsa_priv_key);
539 		if (!DSA_set0_pqg(key->dsa, dsa_p, dsa_q, dsa_g))
540 			fatal_f("DSA_set0_pqg failed");
541 		dsa_p = dsa_q = dsa_g = NULL; /* transferred */
542 		if (!DSA_set0_key(key->dsa, dsa_pub_key, dsa_priv_key))
543 			fatal_f("DSA_set0_key failed");
544 		dsa_pub_key = dsa_priv_key = NULL; /* transferred */
545 		break;
546 	case KEY_RSA:
547 		if ((r = sshbuf_get_u8(b, &e1)) != 0 ||
548 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e2)) != 0) ||
549 		    (e1 < 30 && (r = sshbuf_get_u8(b, &e3)) != 0))
550 			fatal_fr(r, "parse RSA");
551 		e = e1;
552 		debug("e %lx", e);
553 		if (e < 30) {
554 			e <<= 8;
555 			e += e2;
556 			debug("e %lx", e);
557 			e <<= 8;
558 			e += e3;
559 			debug("e %lx", e);
560 		}
561 		if ((rsa_e = BN_new()) == NULL)
562 			fatal_f("BN_new");
563 		if (!BN_set_word(rsa_e, e)) {
564 			BN_clear_free(rsa_e);
565 			sshkey_free(key);
566 			return NULL;
567 		}
568 		if ((rsa_n = BN_new()) == NULL ||
569 		    (rsa_d = BN_new()) == NULL ||
570 		    (rsa_p = BN_new()) == NULL ||
571 		    (rsa_q = BN_new()) == NULL ||
572 		    (rsa_iqmp = BN_new()) == NULL)
573 			fatal_f("BN_new");
574 		buffer_get_bignum_bits(b, rsa_d);
575 		buffer_get_bignum_bits(b, rsa_n);
576 		buffer_get_bignum_bits(b, rsa_iqmp);
577 		buffer_get_bignum_bits(b, rsa_q);
578 		buffer_get_bignum_bits(b, rsa_p);
579 		if (!RSA_set0_key(key->rsa, rsa_n, rsa_e, rsa_d))
580 			fatal_f("RSA_set0_key failed");
581 		rsa_n = rsa_e = rsa_d = NULL; /* transferred */
582 		if (!RSA_set0_factors(key->rsa, rsa_p, rsa_q))
583 			fatal_f("RSA_set0_factors failed");
584 		rsa_p = rsa_q = NULL; /* transferred */
585 		if ((r = ssh_rsa_complete_crt_parameters(key, rsa_iqmp)) != 0)
586 			fatal_fr(r, "generate RSA parameters");
587 		BN_clear_free(rsa_iqmp);
588 		alg = "rsa-sha2-256";
589 		break;
590 	}
591 	rlen = sshbuf_len(b);
592 	if (rlen != 0)
593 		error_f("remaining bytes in key blob %d", rlen);
594 
595 	/* try the key */
596 	if ((r = sshkey_sign(key, &sig, &slen, data, sizeof(data),
597 	    alg, NULL, NULL, 0)) != 0)
598 		error_fr(r, "signing with converted key failed");
599 	else if ((r = sshkey_verify(key, sig, slen, data, sizeof(data),
600 	    alg, 0, NULL)) != 0)
601 		error_fr(r, "verification with converted key failed");
602 	if (r != 0) {
603 		sshkey_free(key);
604 		free(sig);
605 		return NULL;
606 	}
607 	free(sig);
608 	return key;
609 }
610 
611 static int
612 get_line(FILE *fp, char *line, size_t len)
613 {
614 	int c;
615 	size_t pos = 0;
616 
617 	line[0] = '\0';
618 	while ((c = fgetc(fp)) != EOF) {
619 		if (pos >= len - 1)
620 			fatal("input line too long.");
621 		switch (c) {
622 		case '\r':
623 			c = fgetc(fp);
624 			if (c != EOF && c != '\n' && ungetc(c, fp) == EOF)
625 				fatal("unget: %s", strerror(errno));
626 			return pos;
627 		case '\n':
628 			return pos;
629 		}
630 		line[pos++] = c;
631 		line[pos] = '\0';
632 	}
633 	/* We reached EOF */
634 	return -1;
635 }
636 
637 static void
638 do_convert_from_ssh2(struct passwd *pw, struct sshkey **k, int *private)
639 {
640 	int r, blen, escaped = 0;
641 	u_int len;
642 	char line[1024];
643 	struct sshbuf *buf;
644 	char encoded[8096];
645 	FILE *fp;
646 
647 	if ((buf = sshbuf_new()) == NULL)
648 		fatal("sshbuf_new failed");
649 	if ((fp = fopen(identity_file, "r")) == NULL)
650 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
651 	encoded[0] = '\0';
652 	while ((blen = get_line(fp, line, sizeof(line))) != -1) {
653 		if (blen > 0 && line[blen - 1] == '\\')
654 			escaped++;
655 		if (strncmp(line, "----", 4) == 0 ||
656 		    strstr(line, ": ") != NULL) {
657 			if (strstr(line, SSH_COM_PRIVATE_BEGIN) != NULL)
658 				*private = 1;
659 			if (strstr(line, " END ") != NULL) {
660 				break;
661 			}
662 			/* fprintf(stderr, "ignore: %s", line); */
663 			continue;
664 		}
665 		if (escaped) {
666 			escaped--;
667 			/* fprintf(stderr, "escaped: %s", line); */
668 			continue;
669 		}
670 		strlcat(encoded, line, sizeof(encoded));
671 	}
672 	len = strlen(encoded);
673 	if (((len % 4) == 3) &&
674 	    (encoded[len-1] == '=') &&
675 	    (encoded[len-2] == '=') &&
676 	    (encoded[len-3] == '='))
677 		encoded[len-3] = '\0';
678 	if ((r = sshbuf_b64tod(buf, encoded)) != 0)
679 		fatal_fr(r, "base64 decode");
680 	if (*private) {
681 		if ((*k = do_convert_private_ssh2(buf)) == NULL)
682 			fatal_f("private key conversion failed");
683 	} else if ((r = sshkey_fromb(buf, k)) != 0)
684 		fatal_fr(r, "parse key");
685 	sshbuf_free(buf);
686 	fclose(fp);
687 }
688 
689 static void
690 do_convert_from_pkcs8(struct sshkey **k, int *private)
691 {
692 	EVP_PKEY *pubkey;
693 	FILE *fp;
694 
695 	if ((fp = fopen(identity_file, "r")) == NULL)
696 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
697 	if ((pubkey = PEM_read_PUBKEY(fp, NULL, NULL, NULL)) == NULL) {
698 		fatal_f("%s is not a recognised public key format",
699 		    identity_file);
700 	}
701 	fclose(fp);
702 	switch (EVP_PKEY_base_id(pubkey)) {
703 	case EVP_PKEY_RSA:
704 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
705 			fatal("sshkey_new failed");
706 		(*k)->type = KEY_RSA;
707 		(*k)->rsa = EVP_PKEY_get1_RSA(pubkey);
708 		break;
709 	case EVP_PKEY_DSA:
710 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
711 			fatal("sshkey_new failed");
712 		(*k)->type = KEY_DSA;
713 		(*k)->dsa = EVP_PKEY_get1_DSA(pubkey);
714 		break;
715 #ifdef OPENSSL_HAS_ECC
716 	case EVP_PKEY_EC:
717 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
718 			fatal("sshkey_new failed");
719 		(*k)->type = KEY_ECDSA;
720 		(*k)->ecdsa = EVP_PKEY_get1_EC_KEY(pubkey);
721 		(*k)->ecdsa_nid = sshkey_ecdsa_key_to_nid((*k)->ecdsa);
722 		break;
723 #endif
724 	default:
725 		fatal_f("unsupported pubkey type %d",
726 		    EVP_PKEY_base_id(pubkey));
727 	}
728 	EVP_PKEY_free(pubkey);
729 	return;
730 }
731 
732 static void
733 do_convert_from_pem(struct sshkey **k, int *private)
734 {
735 	FILE *fp;
736 	RSA *rsa;
737 
738 	if ((fp = fopen(identity_file, "r")) == NULL)
739 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
740 	if ((rsa = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL)) != NULL) {
741 		if ((*k = sshkey_new(KEY_UNSPEC)) == NULL)
742 			fatal("sshkey_new failed");
743 		(*k)->type = KEY_RSA;
744 		(*k)->rsa = rsa;
745 		fclose(fp);
746 		return;
747 	}
748 	fatal_f("unrecognised raw private key format");
749 }
750 
751 static void
752 do_convert_from(struct passwd *pw)
753 {
754 	struct sshkey *k = NULL;
755 	int r, private = 0, ok = 0;
756 	struct stat st;
757 
758 	if (!have_identity)
759 		ask_filename(pw, "Enter file in which the key is");
760 	if (stat(identity_file, &st) == -1)
761 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
762 
763 	switch (convert_format) {
764 	case FMT_RFC4716:
765 		do_convert_from_ssh2(pw, &k, &private);
766 		break;
767 	case FMT_PKCS8:
768 		do_convert_from_pkcs8(&k, &private);
769 		break;
770 	case FMT_PEM:
771 		do_convert_from_pem(&k, &private);
772 		break;
773 	default:
774 		fatal_f("unknown key format %d", convert_format);
775 	}
776 
777 	if (!private) {
778 		if ((r = sshkey_write(k, stdout)) == 0)
779 			ok = 1;
780 		if (ok)
781 			fprintf(stdout, "\n");
782 	} else {
783 		switch (k->type) {
784 		case KEY_DSA:
785 			ok = PEM_write_DSAPrivateKey(stdout, k->dsa, NULL,
786 			    NULL, 0, NULL, NULL);
787 			break;
788 #ifdef OPENSSL_HAS_ECC
789 		case KEY_ECDSA:
790 			ok = PEM_write_ECPrivateKey(stdout, k->ecdsa, NULL,
791 			    NULL, 0, NULL, NULL);
792 			break;
793 #endif
794 		case KEY_RSA:
795 			ok = PEM_write_RSAPrivateKey(stdout, k->rsa, NULL,
796 			    NULL, 0, NULL, NULL);
797 			break;
798 		default:
799 			fatal_f("unsupported key type %s", sshkey_type(k));
800 		}
801 	}
802 
803 	if (!ok)
804 		fatal("key write failed");
805 	sshkey_free(k);
806 	exit(0);
807 }
808 #endif
809 
810 static void
811 do_print_public(struct passwd *pw)
812 {
813 	struct sshkey *prv;
814 	struct stat st;
815 	int r;
816 	char *comment = NULL;
817 
818 	if (!have_identity)
819 		ask_filename(pw, "Enter file in which the key is");
820 	if (stat(identity_file, &st) == -1)
821 		fatal("%s: %s", identity_file, strerror(errno));
822 	prv = load_identity(identity_file, &comment);
823 	if ((r = sshkey_write(prv, stdout)) != 0)
824 		fatal_fr(r, "write key");
825 	if (comment != NULL && *comment != '\0')
826 		fprintf(stdout, " %s", comment);
827 	fprintf(stdout, "\n");
828 	if (sshkey_is_sk(prv)) {
829 		debug("sk_application: \"%s\", sk_flags 0x%02x",
830 			prv->sk_application, prv->sk_flags);
831 	}
832 	sshkey_free(prv);
833 	free(comment);
834 	exit(0);
835 }
836 
837 static void
838 do_download(struct passwd *pw)
839 {
840 #ifdef ENABLE_PKCS11
841 	struct sshkey **keys = NULL;
842 	int i, nkeys;
843 	enum sshkey_fp_rep rep;
844 	int fptype;
845 	char *fp, *ra, **comments = NULL;
846 
847 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
848 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
849 
850 	pkcs11_init(1);
851 	nkeys = pkcs11_add_provider(pkcs11provider, NULL, &keys, &comments);
852 	if (nkeys <= 0)
853 		fatal("cannot read public key from pkcs11");
854 	for (i = 0; i < nkeys; i++) {
855 		if (print_fingerprint) {
856 			fp = sshkey_fingerprint(keys[i], fptype, rep);
857 			ra = sshkey_fingerprint(keys[i], fingerprint_hash,
858 			    SSH_FP_RANDOMART);
859 			if (fp == NULL || ra == NULL)
860 				fatal_f("sshkey_fingerprint fail");
861 			printf("%u %s %s (PKCS11 key)\n", sshkey_size(keys[i]),
862 			    fp, sshkey_type(keys[i]));
863 			if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
864 				printf("%s\n", ra);
865 			free(ra);
866 			free(fp);
867 		} else {
868 			(void) sshkey_write(keys[i], stdout); /* XXX check */
869 			fprintf(stdout, "%s%s\n",
870 			    *(comments[i]) == '\0' ? "" : " ", comments[i]);
871 		}
872 		free(comments[i]);
873 		sshkey_free(keys[i]);
874 	}
875 	free(comments);
876 	free(keys);
877 	pkcs11_terminate();
878 	exit(0);
879 #else
880 	fatal("no pkcs11 support");
881 #endif /* ENABLE_PKCS11 */
882 }
883 
884 static struct sshkey *
885 try_read_key(char **cpp)
886 {
887 	struct sshkey *ret;
888 	int r;
889 
890 	if ((ret = sshkey_new(KEY_UNSPEC)) == NULL)
891 		fatal("sshkey_new failed");
892 	if ((r = sshkey_read(ret, cpp)) == 0)
893 		return ret;
894 	/* Not a key */
895 	sshkey_free(ret);
896 	return NULL;
897 }
898 
899 static void
900 fingerprint_one_key(const struct sshkey *public, const char *comment)
901 {
902 	char *fp = NULL, *ra = NULL;
903 	enum sshkey_fp_rep rep;
904 	int fptype;
905 
906 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
907 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
908 	fp = sshkey_fingerprint(public, fptype, rep);
909 	ra = sshkey_fingerprint(public, fingerprint_hash, SSH_FP_RANDOMART);
910 	if (fp == NULL || ra == NULL)
911 		fatal_f("sshkey_fingerprint failed");
912 	mprintf("%u %s %s (%s)\n", sshkey_size(public), fp,
913 	    comment ? comment : "no comment", sshkey_type(public));
914 	if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
915 		printf("%s\n", ra);
916 	free(ra);
917 	free(fp);
918 }
919 
920 static void
921 fingerprint_private(const char *path)
922 {
923 	struct stat st;
924 	char *comment = NULL;
925 	struct sshkey *privkey = NULL, *pubkey = NULL;
926 	int r;
927 
928 	if (stat(identity_file, &st) == -1)
929 		fatal("%s: %s", path, strerror(errno));
930 	if ((r = sshkey_load_public(path, &pubkey, &comment)) != 0)
931 		debug_r(r, "load public \"%s\"", path);
932 	if (pubkey == NULL || comment == NULL || *comment == '\0') {
933 		free(comment);
934 		if ((r = sshkey_load_private(path, NULL,
935 		    &privkey, &comment)) != 0)
936 			debug_r(r, "load private \"%s\"", path);
937 	}
938 	if (pubkey == NULL && privkey == NULL)
939 		fatal("%s is not a key file.", path);
940 
941 	fingerprint_one_key(pubkey == NULL ? privkey : pubkey, comment);
942 	sshkey_free(pubkey);
943 	sshkey_free(privkey);
944 	free(comment);
945 }
946 
947 static void
948 do_fingerprint(struct passwd *pw)
949 {
950 	FILE *f;
951 	struct sshkey *public = NULL;
952 	char *comment = NULL, *cp, *ep, *line = NULL;
953 	size_t linesize = 0;
954 	int i, invalid = 1;
955 	const char *path;
956 	u_long lnum = 0;
957 
958 	if (!have_identity)
959 		ask_filename(pw, "Enter file in which the key is");
960 	path = identity_file;
961 
962 	if (strcmp(identity_file, "-") == 0) {
963 		f = stdin;
964 		path = "(stdin)";
965 	} else if ((f = fopen(path, "r")) == NULL)
966 		fatal("%s: %s: %s", __progname, path, strerror(errno));
967 
968 	while (getline(&line, &linesize, f) != -1) {
969 		lnum++;
970 		cp = line;
971 		cp[strcspn(cp, "\n")] = '\0';
972 		/* Trim leading space and comments */
973 		cp = line + strspn(line, " \t");
974 		if (*cp == '#' || *cp == '\0')
975 			continue;
976 
977 		/*
978 		 * Input may be plain keys, private keys, authorized_keys
979 		 * or known_hosts.
980 		 */
981 
982 		/*
983 		 * Try private keys first. Assume a key is private if
984 		 * "SSH PRIVATE KEY" appears on the first line and we're
985 		 * not reading from stdin (XXX support private keys on stdin).
986 		 */
987 		if (lnum == 1 && strcmp(identity_file, "-") != 0 &&
988 		    strstr(cp, "PRIVATE KEY") != NULL) {
989 			free(line);
990 			fclose(f);
991 			fingerprint_private(path);
992 			exit(0);
993 		}
994 
995 		/*
996 		 * If it's not a private key, then this must be prepared to
997 		 * accept a public key prefixed with a hostname or options.
998 		 * Try a bare key first, otherwise skip the leading stuff.
999 		 */
1000 		if ((public = try_read_key(&cp)) == NULL) {
1001 			i = strtol(cp, &ep, 10);
1002 			if (i == 0 || ep == NULL ||
1003 			    (*ep != ' ' && *ep != '\t')) {
1004 				int quoted = 0;
1005 
1006 				comment = cp;
1007 				for (; *cp && (quoted || (*cp != ' ' &&
1008 				    *cp != '\t')); cp++) {
1009 					if (*cp == '\\' && cp[1] == '"')
1010 						cp++;	/* Skip both */
1011 					else if (*cp == '"')
1012 						quoted = !quoted;
1013 				}
1014 				if (!*cp)
1015 					continue;
1016 				*cp++ = '\0';
1017 			}
1018 		}
1019 		/* Retry after parsing leading hostname/key options */
1020 		if (public == NULL && (public = try_read_key(&cp)) == NULL) {
1021 			debug("%s:%lu: not a public key", path, lnum);
1022 			continue;
1023 		}
1024 
1025 		/* Find trailing comment, if any */
1026 		for (; *cp == ' ' || *cp == '\t'; cp++)
1027 			;
1028 		if (*cp != '\0' && *cp != '#')
1029 			comment = cp;
1030 
1031 		fingerprint_one_key(public, comment);
1032 		sshkey_free(public);
1033 		invalid = 0; /* One good key in the file is sufficient */
1034 	}
1035 	fclose(f);
1036 	free(line);
1037 
1038 	if (invalid)
1039 		fatal("%s is not a public key file.", path);
1040 	exit(0);
1041 }
1042 
1043 static void
1044 do_gen_all_hostkeys(struct passwd *pw)
1045 {
1046 	struct {
1047 		char *key_type;
1048 		char *key_type_display;
1049 		char *path;
1050 	} key_types[] = {
1051 #ifdef WITH_OPENSSL
1052 		{ "rsa", "RSA" ,_PATH_HOST_RSA_KEY_FILE },
1053 #ifdef OPENSSL_HAS_ECC
1054 		{ "ecdsa", "ECDSA",_PATH_HOST_ECDSA_KEY_FILE },
1055 #endif /* OPENSSL_HAS_ECC */
1056 #endif /* WITH_OPENSSL */
1057 		{ "ed25519", "ED25519",_PATH_HOST_ED25519_KEY_FILE },
1058 #ifdef WITH_XMSS
1059 		{ "xmss", "XMSS",_PATH_HOST_XMSS_KEY_FILE },
1060 #endif /* WITH_XMSS */
1061 		{ NULL, NULL, NULL }
1062 	};
1063 
1064 	u_int32_t bits = 0;
1065 	int first = 0;
1066 	struct stat st;
1067 	struct sshkey *private, *public;
1068 	char comment[1024], *prv_tmp, *pub_tmp, *prv_file, *pub_file;
1069 	int i, type, fd, r;
1070 
1071 	for (i = 0; key_types[i].key_type; i++) {
1072 		public = private = NULL;
1073 		prv_tmp = pub_tmp = prv_file = pub_file = NULL;
1074 
1075 		xasprintf(&prv_file, "%s%s",
1076 		    identity_file, key_types[i].path);
1077 
1078 		/* Check whether private key exists and is not zero-length */
1079 		if (stat(prv_file, &st) == 0) {
1080 			if (st.st_size != 0)
1081 				goto next;
1082 		} else if (errno != ENOENT) {
1083 			error("Could not stat %s: %s", key_types[i].path,
1084 			    strerror(errno));
1085 			goto failnext;
1086 		}
1087 
1088 		/*
1089 		 * Private key doesn't exist or is invalid; proceed with
1090 		 * key generation.
1091 		 */
1092 		xasprintf(&prv_tmp, "%s%s.XXXXXXXXXX",
1093 		    identity_file, key_types[i].path);
1094 		xasprintf(&pub_tmp, "%s%s.pub.XXXXXXXXXX",
1095 		    identity_file, key_types[i].path);
1096 		xasprintf(&pub_file, "%s%s.pub",
1097 		    identity_file, key_types[i].path);
1098 
1099 		if (first == 0) {
1100 			first = 1;
1101 			printf("%s: generating new host keys: ", __progname);
1102 		}
1103 		printf("%s ", key_types[i].key_type_display);
1104 		fflush(stdout);
1105 		type = sshkey_type_from_name(key_types[i].key_type);
1106 		if ((fd = mkstemp(prv_tmp)) == -1) {
1107 			error("Could not save your private key in %s: %s",
1108 			    prv_tmp, strerror(errno));
1109 			goto failnext;
1110 		}
1111 		(void)close(fd); /* just using mkstemp() to reserve a name */
1112 		bits = 0;
1113 		type_bits_valid(type, NULL, &bits);
1114 		if ((r = sshkey_generate(type, bits, &private)) != 0) {
1115 			error_r(r, "sshkey_generate failed");
1116 			goto failnext;
1117 		}
1118 		if ((r = sshkey_from_private(private, &public)) != 0)
1119 			fatal_fr(r, "sshkey_from_private");
1120 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name,
1121 		    hostname);
1122 		if ((r = sshkey_save_private(private, prv_tmp, "",
1123 		    comment, private_key_format, openssh_format_cipher,
1124 		    rounds)) != 0) {
1125 			error_r(r, "Saving key \"%s\" failed", prv_tmp);
1126 			goto failnext;
1127 		}
1128 		if ((fd = mkstemp(pub_tmp)) == -1) {
1129 			error("Could not save your public key in %s: %s",
1130 			    pub_tmp, strerror(errno));
1131 			goto failnext;
1132 		}
1133 		(void)fchmod(fd, 0644);
1134 		(void)close(fd);
1135 		if ((r = sshkey_save_public(public, pub_tmp, comment)) != 0) {
1136 			error_r(r, "Unable to save public key to %s",
1137 			    identity_file);
1138 			goto failnext;
1139 		}
1140 
1141 		/* Rename temporary files to their permanent locations. */
1142 		if (rename(pub_tmp, pub_file) != 0) {
1143 			error("Unable to move %s into position: %s",
1144 			    pub_file, strerror(errno));
1145 			goto failnext;
1146 		}
1147 		if (rename(prv_tmp, prv_file) != 0) {
1148 			error("Unable to move %s into position: %s",
1149 			    key_types[i].path, strerror(errno));
1150  failnext:
1151 			first = 0;
1152 			goto next;
1153 		}
1154  next:
1155 		sshkey_free(private);
1156 		sshkey_free(public);
1157 		free(prv_tmp);
1158 		free(pub_tmp);
1159 		free(prv_file);
1160 		free(pub_file);
1161 	}
1162 	if (first != 0)
1163 		printf("\n");
1164 }
1165 
1166 struct known_hosts_ctx {
1167 	const char *host;	/* Hostname searched for in find/delete case */
1168 	FILE *out;		/* Output file, stdout for find_hosts case */
1169 	int has_unhashed;	/* When hashing, original had unhashed hosts */
1170 	int found_key;		/* For find/delete, host was found */
1171 	int invalid;		/* File contained invalid items; don't delete */
1172 	int hash_hosts;		/* Hash hostnames as we go */
1173 	int find_host;		/* Search for specific hostname */
1174 	int delete_host;	/* Delete host from known_hosts */
1175 };
1176 
1177 static int
1178 known_hosts_hash(struct hostkey_foreach_line *l, void *_ctx)
1179 {
1180 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1181 	char *hashed, *cp, *hosts, *ohosts;
1182 	int has_wild = l->hosts && strcspn(l->hosts, "*?!") != strlen(l->hosts);
1183 	int was_hashed = l->hosts && l->hosts[0] == HASH_DELIM;
1184 
1185 	switch (l->status) {
1186 	case HKF_STATUS_OK:
1187 	case HKF_STATUS_MATCHED:
1188 		/*
1189 		 * Don't hash hosts already already hashed, with wildcard
1190 		 * characters or a CA/revocation marker.
1191 		 */
1192 		if (was_hashed || has_wild || l->marker != MRK_NONE) {
1193 			fprintf(ctx->out, "%s\n", l->line);
1194 			if (has_wild && !ctx->find_host) {
1195 				logit("%s:%lu: ignoring host name "
1196 				    "with wildcard: %.64s", l->path,
1197 				    l->linenum, l->hosts);
1198 			}
1199 			return 0;
1200 		}
1201 		/*
1202 		 * Split any comma-separated hostnames from the host list,
1203 		 * hash and store separately.
1204 		 */
1205 		ohosts = hosts = xstrdup(l->hosts);
1206 		while ((cp = strsep(&hosts, ",")) != NULL && *cp != '\0') {
1207 			lowercase(cp);
1208 			if ((hashed = host_hash(cp, NULL, 0)) == NULL)
1209 				fatal("hash_host failed");
1210 			fprintf(ctx->out, "%s %s\n", hashed, l->rawkey);
1211 			free(hashed);
1212 			ctx->has_unhashed = 1;
1213 		}
1214 		free(ohosts);
1215 		return 0;
1216 	case HKF_STATUS_INVALID:
1217 		/* Retain invalid lines, but mark file as invalid. */
1218 		ctx->invalid = 1;
1219 		logit("%s:%lu: invalid line", l->path, l->linenum);
1220 		/* FALLTHROUGH */
1221 	default:
1222 		fprintf(ctx->out, "%s\n", l->line);
1223 		return 0;
1224 	}
1225 	/* NOTREACHED */
1226 	return -1;
1227 }
1228 
1229 static int
1230 known_hosts_find_delete(struct hostkey_foreach_line *l, void *_ctx)
1231 {
1232 	struct known_hosts_ctx *ctx = (struct known_hosts_ctx *)_ctx;
1233 	enum sshkey_fp_rep rep;
1234 	int fptype;
1235 	char *fp = NULL, *ra = NULL;
1236 
1237 	fptype = print_bubblebabble ? SSH_DIGEST_SHA1 : fingerprint_hash;
1238 	rep =    print_bubblebabble ? SSH_FP_BUBBLEBABBLE : SSH_FP_DEFAULT;
1239 
1240 	if (l->status == HKF_STATUS_MATCHED) {
1241 		if (ctx->delete_host) {
1242 			if (l->marker != MRK_NONE) {
1243 				/* Don't remove CA and revocation lines */
1244 				fprintf(ctx->out, "%s\n", l->line);
1245 			} else {
1246 				/*
1247 				 * Hostname matches and has no CA/revoke
1248 				 * marker, delete it by *not* writing the
1249 				 * line to ctx->out.
1250 				 */
1251 				ctx->found_key = 1;
1252 				if (!quiet)
1253 					printf("# Host %s found: line %lu\n",
1254 					    ctx->host, l->linenum);
1255 			}
1256 			return 0;
1257 		} else if (ctx->find_host) {
1258 			ctx->found_key = 1;
1259 			if (!quiet) {
1260 				printf("# Host %s found: line %lu %s\n",
1261 				    ctx->host,
1262 				    l->linenum, l->marker == MRK_CA ? "CA" :
1263 				    (l->marker == MRK_REVOKE ? "REVOKED" : ""));
1264 			}
1265 			if (ctx->hash_hosts)
1266 				known_hosts_hash(l, ctx);
1267 			else if (print_fingerprint) {
1268 				fp = sshkey_fingerprint(l->key, fptype, rep);
1269 				ra = sshkey_fingerprint(l->key,
1270 				    fingerprint_hash, SSH_FP_RANDOMART);
1271 				if (fp == NULL || ra == NULL)
1272 					fatal_f("sshkey_fingerprint failed");
1273 				mprintf("%s %s %s%s%s\n", ctx->host,
1274 				    sshkey_type(l->key), fp,
1275 				    l->comment[0] ? " " : "",
1276 				    l->comment);
1277 				if (log_level_get() >= SYSLOG_LEVEL_VERBOSE)
1278 					printf("%s\n", ra);
1279 				free(ra);
1280 				free(fp);
1281 			} else
1282 				fprintf(ctx->out, "%s\n", l->line);
1283 			return 0;
1284 		}
1285 	} else if (ctx->delete_host) {
1286 		/* Retain non-matching hosts when deleting */
1287 		if (l->status == HKF_STATUS_INVALID) {
1288 			ctx->invalid = 1;
1289 			logit("%s:%lu: invalid line", l->path, l->linenum);
1290 		}
1291 		fprintf(ctx->out, "%s\n", l->line);
1292 	}
1293 	return 0;
1294 }
1295 
1296 static void
1297 do_known_hosts(struct passwd *pw, const char *name, int find_host,
1298     int delete_host, int hash_hosts)
1299 {
1300 	char *cp, tmp[PATH_MAX], old[PATH_MAX];
1301 	int r, fd, oerrno, inplace = 0;
1302 	struct known_hosts_ctx ctx;
1303 	u_int foreach_options;
1304 	struct stat sb;
1305 
1306 	if (!have_identity) {
1307 		cp = tilde_expand_filename(_PATH_SSH_USER_HOSTFILE, pw->pw_uid);
1308 		if (strlcpy(identity_file, cp, sizeof(identity_file)) >=
1309 		    sizeof(identity_file))
1310 			fatal("Specified known hosts path too long");
1311 		free(cp);
1312 		have_identity = 1;
1313 	}
1314 	if (stat(identity_file, &sb) != 0)
1315 		fatal("Cannot stat %s: %s", identity_file, strerror(errno));
1316 
1317 	memset(&ctx, 0, sizeof(ctx));
1318 	ctx.out = stdout;
1319 	ctx.host = name;
1320 	ctx.hash_hosts = hash_hosts;
1321 	ctx.find_host = find_host;
1322 	ctx.delete_host = delete_host;
1323 
1324 	/*
1325 	 * Find hosts goes to stdout, hash and deletions happen in-place
1326 	 * A corner case is ssh-keygen -HF foo, which should go to stdout
1327 	 */
1328 	if (!find_host && (hash_hosts || delete_host)) {
1329 		if (strlcpy(tmp, identity_file, sizeof(tmp)) >= sizeof(tmp) ||
1330 		    strlcat(tmp, ".XXXXXXXXXX", sizeof(tmp)) >= sizeof(tmp) ||
1331 		    strlcpy(old, identity_file, sizeof(old)) >= sizeof(old) ||
1332 		    strlcat(old, ".old", sizeof(old)) >= sizeof(old))
1333 			fatal("known_hosts path too long");
1334 		umask(077);
1335 		if ((fd = mkstemp(tmp)) == -1)
1336 			fatal("mkstemp: %s", strerror(errno));
1337 		if ((ctx.out = fdopen(fd, "w")) == NULL) {
1338 			oerrno = errno;
1339 			unlink(tmp);
1340 			fatal("fdopen: %s", strerror(oerrno));
1341 		}
1342 		(void)fchmod(fd, sb.st_mode & 0644);
1343 		inplace = 1;
1344 	}
1345 	/* XXX support identity_file == "-" for stdin */
1346 	foreach_options = find_host ? HKF_WANT_MATCH : 0;
1347 	foreach_options |= print_fingerprint ? HKF_WANT_PARSE_KEY : 0;
1348 	if ((r = hostkeys_foreach(identity_file, (find_host || !hash_hosts) ?
1349 	    known_hosts_find_delete : known_hosts_hash, &ctx, name, NULL,
1350 	    foreach_options, 0)) != 0) {
1351 		if (inplace)
1352 			unlink(tmp);
1353 		fatal_fr(r, "hostkeys_foreach");
1354 	}
1355 
1356 	if (inplace)
1357 		fclose(ctx.out);
1358 
1359 	if (ctx.invalid) {
1360 		error("%s is not a valid known_hosts file.", identity_file);
1361 		if (inplace) {
1362 			error("Not replacing existing known_hosts "
1363 			    "file because of errors");
1364 			unlink(tmp);
1365 		}
1366 		exit(1);
1367 	} else if (delete_host && !ctx.found_key) {
1368 		logit("Host %s not found in %s", name, identity_file);
1369 		if (inplace)
1370 			unlink(tmp);
1371 	} else if (inplace) {
1372 		/* Backup existing file */
1373 		if (unlink(old) == -1 && errno != ENOENT)
1374 			fatal("unlink %.100s: %s", old, strerror(errno));
1375 		if (link(identity_file, old) == -1)
1376 			fatal("link %.100s to %.100s: %s", identity_file, old,
1377 			    strerror(errno));
1378 		/* Move new one into place */
1379 		if (rename(tmp, identity_file) == -1) {
1380 			error("rename\"%s\" to \"%s\": %s", tmp, identity_file,
1381 			    strerror(errno));
1382 			unlink(tmp);
1383 			unlink(old);
1384 			exit(1);
1385 		}
1386 
1387 		printf("%s updated.\n", identity_file);
1388 		printf("Original contents retained as %s\n", old);
1389 		if (ctx.has_unhashed) {
1390 			logit("WARNING: %s contains unhashed entries", old);
1391 			logit("Delete this file to ensure privacy "
1392 			    "of hostnames");
1393 		}
1394 	}
1395 
1396 	exit (find_host && !ctx.found_key);
1397 }
1398 
1399 /*
1400  * Perform changing a passphrase.  The argument is the passwd structure
1401  * for the current user.
1402  */
1403 static void
1404 do_change_passphrase(struct passwd *pw)
1405 {
1406 	char *comment;
1407 	char *old_passphrase, *passphrase1, *passphrase2;
1408 	struct stat st;
1409 	struct sshkey *private;
1410 	int r;
1411 
1412 	if (!have_identity)
1413 		ask_filename(pw, "Enter file in which the key is");
1414 	if (stat(identity_file, &st) == -1)
1415 		fatal("%s: %s", identity_file, strerror(errno));
1416 	/* Try to load the file with empty passphrase. */
1417 	r = sshkey_load_private(identity_file, "", &private, &comment);
1418 	if (r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1419 		if (identity_passphrase)
1420 			old_passphrase = xstrdup(identity_passphrase);
1421 		else
1422 			old_passphrase =
1423 			    read_passphrase("Enter old passphrase: ",
1424 			    RP_ALLOW_STDIN);
1425 		r = sshkey_load_private(identity_file, old_passphrase,
1426 		    &private, &comment);
1427 		freezero(old_passphrase, strlen(old_passphrase));
1428 		if (r != 0)
1429 			goto badkey;
1430 	} else if (r != 0) {
1431  badkey:
1432 		fatal_r(r, "Failed to load key %s", identity_file);
1433 	}
1434 	if (comment)
1435 		mprintf("Key has comment '%s'\n", comment);
1436 
1437 	/* Ask the new passphrase (twice). */
1438 	if (identity_new_passphrase) {
1439 		passphrase1 = xstrdup(identity_new_passphrase);
1440 		passphrase2 = NULL;
1441 	} else {
1442 		passphrase1 =
1443 			read_passphrase("Enter new passphrase (empty for no "
1444 			    "passphrase): ", RP_ALLOW_STDIN);
1445 		passphrase2 = read_passphrase("Enter same passphrase again: ",
1446 		    RP_ALLOW_STDIN);
1447 
1448 		/* Verify that they are the same. */
1449 		if (strcmp(passphrase1, passphrase2) != 0) {
1450 			explicit_bzero(passphrase1, strlen(passphrase1));
1451 			explicit_bzero(passphrase2, strlen(passphrase2));
1452 			free(passphrase1);
1453 			free(passphrase2);
1454 			printf("Pass phrases do not match.  Try again.\n");
1455 			exit(1);
1456 		}
1457 		/* Destroy the other copy. */
1458 		freezero(passphrase2, strlen(passphrase2));
1459 	}
1460 
1461 	/* Save the file using the new passphrase. */
1462 	if ((r = sshkey_save_private(private, identity_file, passphrase1,
1463 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
1464 		error_r(r, "Saving key \"%s\" failed", identity_file);
1465 		freezero(passphrase1, strlen(passphrase1));
1466 		sshkey_free(private);
1467 		free(comment);
1468 		exit(1);
1469 	}
1470 	/* Destroy the passphrase and the copy of the key in memory. */
1471 	freezero(passphrase1, strlen(passphrase1));
1472 	sshkey_free(private);		 /* Destroys contents */
1473 	free(comment);
1474 
1475 	printf("Your identification has been saved with the new passphrase.\n");
1476 	exit(0);
1477 }
1478 
1479 /*
1480  * Print the SSHFP RR.
1481  */
1482 static int
1483 do_print_resource_record(struct passwd *pw, char *fname, char *hname,
1484     int print_generic, char * const *opts, size_t nopts)
1485 {
1486 	struct sshkey *public;
1487 	char *comment = NULL;
1488 	struct stat st;
1489 	int r, hash = -1;
1490 	size_t i;
1491 
1492 	for (i = 0; i < nopts; i++) {
1493 		if (strncasecmp(opts[i], "hashalg=", 8) == 0) {
1494 			if ((hash = ssh_digest_alg_by_name(opts[i] + 8)) == -1)
1495 				fatal("Unsupported hash algorithm");
1496 		} else {
1497 			error("Invalid option \"%s\"", opts[i]);
1498 			return SSH_ERR_INVALID_ARGUMENT;
1499 		}
1500 	}
1501 	if (fname == NULL)
1502 		fatal_f("no filename");
1503 	if (stat(fname, &st) == -1) {
1504 		if (errno == ENOENT)
1505 			return 0;
1506 		fatal("%s: %s", fname, strerror(errno));
1507 	}
1508 	if ((r = sshkey_load_public(fname, &public, &comment)) != 0)
1509 		fatal_r(r, "Failed to read v2 public key from \"%s\"", fname);
1510 	export_dns_rr(hname, public, stdout, print_generic, hash);
1511 	sshkey_free(public);
1512 	free(comment);
1513 	return 1;
1514 }
1515 
1516 /*
1517  * Change the comment of a private key file.
1518  */
1519 static void
1520 do_change_comment(struct passwd *pw, const char *identity_comment)
1521 {
1522 	char new_comment[1024], *comment, *passphrase;
1523 	struct sshkey *private;
1524 	struct sshkey *public;
1525 	struct stat st;
1526 	int r;
1527 
1528 	if (!have_identity)
1529 		ask_filename(pw, "Enter file in which the key is");
1530 	if (stat(identity_file, &st) == -1)
1531 		fatal("%s: %s", identity_file, strerror(errno));
1532 	if ((r = sshkey_load_private(identity_file, "",
1533 	    &private, &comment)) == 0)
1534 		passphrase = xstrdup("");
1535 	else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
1536 		fatal_r(r, "Cannot load private key \"%s\"", identity_file);
1537 	else {
1538 		if (identity_passphrase)
1539 			passphrase = xstrdup(identity_passphrase);
1540 		else if (identity_new_passphrase)
1541 			passphrase = xstrdup(identity_new_passphrase);
1542 		else
1543 			passphrase = read_passphrase("Enter passphrase: ",
1544 			    RP_ALLOW_STDIN);
1545 		/* Try to load using the passphrase. */
1546 		if ((r = sshkey_load_private(identity_file, passphrase,
1547 		    &private, &comment)) != 0) {
1548 			freezero(passphrase, strlen(passphrase));
1549 			fatal_r(r, "Cannot load private key \"%s\"",
1550 			    identity_file);
1551 		}
1552 	}
1553 
1554 	if (private->type != KEY_ED25519 && private->type != KEY_XMSS &&
1555 	    private_key_format != SSHKEY_PRIVATE_OPENSSH) {
1556 		error("Comments are only supported for keys stored in "
1557 		    "the new format (-o).");
1558 		explicit_bzero(passphrase, strlen(passphrase));
1559 		sshkey_free(private);
1560 		exit(1);
1561 	}
1562 	if (comment)
1563 		printf("Old comment: %s\n", comment);
1564 	else
1565 		printf("No existing comment\n");
1566 
1567 	if (identity_comment) {
1568 		strlcpy(new_comment, identity_comment, sizeof(new_comment));
1569 	} else {
1570 		printf("New comment: ");
1571 		fflush(stdout);
1572 		if (!fgets(new_comment, sizeof(new_comment), stdin)) {
1573 			explicit_bzero(passphrase, strlen(passphrase));
1574 			sshkey_free(private);
1575 			exit(1);
1576 		}
1577 		new_comment[strcspn(new_comment, "\n")] = '\0';
1578 	}
1579 	if (comment != NULL && strcmp(comment, new_comment) == 0) {
1580 		printf("No change to comment\n");
1581 		free(passphrase);
1582 		sshkey_free(private);
1583 		free(comment);
1584 		exit(0);
1585 	}
1586 
1587 	/* Save the file using the new passphrase. */
1588 	if ((r = sshkey_save_private(private, identity_file, passphrase,
1589 	    new_comment, private_key_format, openssh_format_cipher,
1590 	    rounds)) != 0) {
1591 		error_r(r, "Saving key \"%s\" failed", identity_file);
1592 		freezero(passphrase, strlen(passphrase));
1593 		sshkey_free(private);
1594 		free(comment);
1595 		exit(1);
1596 	}
1597 	freezero(passphrase, strlen(passphrase));
1598 	if ((r = sshkey_from_private(private, &public)) != 0)
1599 		fatal_fr(r, "sshkey_from_private");
1600 	sshkey_free(private);
1601 
1602 	strlcat(identity_file, ".pub", sizeof(identity_file));
1603 	if ((r = sshkey_save_public(public, identity_file, new_comment)) != 0)
1604 		fatal_r(r, "Unable to save public key to %s", identity_file);
1605 	sshkey_free(public);
1606 	free(comment);
1607 
1608 	if (strlen(new_comment) > 0)
1609 		printf("Comment '%s' applied\n", new_comment);
1610 	else
1611 		printf("Comment removed\n");
1612 
1613 	exit(0);
1614 }
1615 
1616 static void
1617 cert_ext_add(const char *key, const char *value, int iscrit)
1618 {
1619 	cert_ext = xreallocarray(cert_ext, ncert_ext + 1, sizeof(*cert_ext));
1620 	cert_ext[ncert_ext].key = xstrdup(key);
1621 	cert_ext[ncert_ext].val = value == NULL ? NULL : xstrdup(value);
1622 	cert_ext[ncert_ext].crit = iscrit;
1623 	ncert_ext++;
1624 }
1625 
1626 /* qsort(3) comparison function for certificate extensions */
1627 static int
1628 cert_ext_cmp(const void *_a, const void *_b)
1629 {
1630 	const struct cert_ext *a = (const struct cert_ext *)_a;
1631 	const struct cert_ext *b = (const struct cert_ext *)_b;
1632 	int r;
1633 
1634 	if (a->crit != b->crit)
1635 		return (a->crit < b->crit) ? -1 : 1;
1636 	if ((r = strcmp(a->key, b->key)) != 0)
1637 		return r;
1638 	if ((a->val == NULL) != (b->val == NULL))
1639 		return (a->val == NULL) ? -1 : 1;
1640 	if (a->val != NULL && (r = strcmp(a->val, b->val)) != 0)
1641 		return r;
1642 	return 0;
1643 }
1644 
1645 #define OPTIONS_CRITICAL	1
1646 #define OPTIONS_EXTENSIONS	2
1647 static void
1648 prepare_options_buf(struct sshbuf *c, int which)
1649 {
1650 	struct sshbuf *b;
1651 	size_t i;
1652 	int r;
1653 	const struct cert_ext *ext;
1654 
1655 	if ((b = sshbuf_new()) == NULL)
1656 		fatal_f("sshbuf_new failed");
1657 	sshbuf_reset(c);
1658 	for (i = 0; i < ncert_ext; i++) {
1659 		ext = &cert_ext[i];
1660 		if ((ext->crit && (which & OPTIONS_EXTENSIONS)) ||
1661 		    (!ext->crit && (which & OPTIONS_CRITICAL)))
1662 			continue;
1663 		if (ext->val == NULL) {
1664 			/* flag option */
1665 			debug3_f("%s", ext->key);
1666 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1667 			    (r = sshbuf_put_string(c, NULL, 0)) != 0)
1668 				fatal_fr(r, "prepare flag");
1669 		} else {
1670 			/* key/value option */
1671 			debug3_f("%s=%s", ext->key, ext->val);
1672 			sshbuf_reset(b);
1673 			if ((r = sshbuf_put_cstring(c, ext->key)) != 0 ||
1674 			    (r = sshbuf_put_cstring(b, ext->val)) != 0 ||
1675 			    (r = sshbuf_put_stringb(c, b)) != 0)
1676 				fatal_fr(r, "prepare k/v");
1677 		}
1678 	}
1679 	sshbuf_free(b);
1680 }
1681 
1682 static void
1683 finalise_cert_exts(void)
1684 {
1685 	/* critical options */
1686 	if (certflags_command != NULL)
1687 		cert_ext_add("force-command", certflags_command, 1);
1688 	if (certflags_src_addr != NULL)
1689 		cert_ext_add("source-address", certflags_src_addr, 1);
1690 	if ((certflags_flags & CERTOPT_REQUIRE_VERIFY) != 0)
1691 		cert_ext_add("verify-required", NULL, 1);
1692 	/* extensions */
1693 	if ((certflags_flags & CERTOPT_X_FWD) != 0)
1694 		cert_ext_add("permit-X11-forwarding", NULL, 0);
1695 	if ((certflags_flags & CERTOPT_AGENT_FWD) != 0)
1696 		cert_ext_add("permit-agent-forwarding", NULL, 0);
1697 	if ((certflags_flags & CERTOPT_PORT_FWD) != 0)
1698 		cert_ext_add("permit-port-forwarding", NULL, 0);
1699 	if ((certflags_flags & CERTOPT_PTY) != 0)
1700 		cert_ext_add("permit-pty", NULL, 0);
1701 	if ((certflags_flags & CERTOPT_USER_RC) != 0)
1702 		cert_ext_add("permit-user-rc", NULL, 0);
1703 	if ((certflags_flags & CERTOPT_NO_REQUIRE_USER_PRESENCE) != 0)
1704 		cert_ext_add("no-touch-required", NULL, 0);
1705 	/* order lexically by key */
1706 	if (ncert_ext > 0)
1707 		qsort(cert_ext, ncert_ext, sizeof(*cert_ext), cert_ext_cmp);
1708 }
1709 
1710 static struct sshkey *
1711 load_pkcs11_key(char *path)
1712 {
1713 #ifdef ENABLE_PKCS11
1714 	struct sshkey **keys = NULL, *public, *private = NULL;
1715 	int r, i, nkeys;
1716 
1717 	if ((r = sshkey_load_public(path, &public, NULL)) != 0)
1718 		fatal_r(r, "Couldn't load CA public key \"%s\"", path);
1719 
1720 	nkeys = pkcs11_add_provider(pkcs11provider, identity_passphrase,
1721 	    &keys, NULL);
1722 	debug3_f("%d keys", nkeys);
1723 	if (nkeys <= 0)
1724 		fatal("cannot read public key from pkcs11");
1725 	for (i = 0; i < nkeys; i++) {
1726 		if (sshkey_equal_public(public, keys[i])) {
1727 			private = keys[i];
1728 			continue;
1729 		}
1730 		sshkey_free(keys[i]);
1731 	}
1732 	free(keys);
1733 	sshkey_free(public);
1734 	return private;
1735 #else
1736 	fatal("no pkcs11 support");
1737 #endif /* ENABLE_PKCS11 */
1738 }
1739 
1740 /* Signer for sshkey_certify_custom that uses the agent */
1741 static int
1742 agent_signer(struct sshkey *key, u_char **sigp, size_t *lenp,
1743     const u_char *data, size_t datalen,
1744     const char *alg, const char *provider, const char *pin,
1745     u_int compat, void *ctx)
1746 {
1747 	int *agent_fdp = (int *)ctx;
1748 
1749 	return ssh_agent_sign(*agent_fdp, key, sigp, lenp,
1750 	    data, datalen, alg, compat);
1751 }
1752 
1753 static void
1754 do_ca_sign(struct passwd *pw, const char *ca_key_path, int prefer_agent,
1755     unsigned long long cert_serial, int cert_serial_autoinc,
1756     int argc, char **argv)
1757 {
1758 	int r, i, found, agent_fd = -1;
1759 	u_int n;
1760 	struct sshkey *ca, *public;
1761 	char valid[64], *otmp, *tmp, *cp, *out, *comment;
1762 	char *ca_fp = NULL, **plist = NULL, *pin = NULL;
1763 	struct ssh_identitylist *agent_ids;
1764 	size_t j;
1765 	struct notifier_ctx *notifier = NULL;
1766 
1767 #ifdef ENABLE_PKCS11
1768 	pkcs11_init(1);
1769 #endif
1770 	tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
1771 	if (pkcs11provider != NULL) {
1772 		/* If a PKCS#11 token was specified then try to use it */
1773 		if ((ca = load_pkcs11_key(tmp)) == NULL)
1774 			fatal("No PKCS#11 key matching %s found", ca_key_path);
1775 	} else if (prefer_agent) {
1776 		/*
1777 		 * Agent signature requested. Try to use agent after making
1778 		 * sure the public key specified is actually present in the
1779 		 * agent.
1780 		 */
1781 		if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
1782 			fatal_r(r, "Cannot load CA public key %s", tmp);
1783 		if ((r = ssh_get_authentication_socket(&agent_fd)) != 0)
1784 			fatal_r(r, "Cannot use public key for CA signature");
1785 		if ((r = ssh_fetch_identitylist(agent_fd, &agent_ids)) != 0)
1786 			fatal_r(r, "Retrieve agent key list");
1787 		found = 0;
1788 		for (j = 0; j < agent_ids->nkeys; j++) {
1789 			if (sshkey_equal(ca, agent_ids->keys[j])) {
1790 				found = 1;
1791 				break;
1792 			}
1793 		}
1794 		if (!found)
1795 			fatal("CA key %s not found in agent", tmp);
1796 		ssh_free_identitylist(agent_ids);
1797 		ca->flags |= SSHKEY_FLAG_EXT;
1798 	} else {
1799 		/* CA key is assumed to be a private key on the filesystem */
1800 		ca = load_identity(tmp, NULL);
1801 		if (sshkey_is_sk(ca) &&
1802 		    (ca->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
1803 			if ((pin = read_passphrase("Enter PIN for CA key: ",
1804 			    RP_ALLOW_STDIN)) == NULL)
1805 				fatal_f("couldn't read PIN");
1806 		}
1807 	}
1808 	free(tmp);
1809 
1810 	if (key_type_name != NULL) {
1811 		if (sshkey_type_from_name(key_type_name) != ca->type) {
1812 			fatal("CA key type %s doesn't match specified %s",
1813 			    sshkey_ssh_name(ca), key_type_name);
1814 		}
1815 	} else if (ca->type == KEY_RSA) {
1816 		/* Default to a good signature algorithm */
1817 		key_type_name = "rsa-sha2-512";
1818 	}
1819 	ca_fp = sshkey_fingerprint(ca, fingerprint_hash, SSH_FP_DEFAULT);
1820 
1821 	finalise_cert_exts();
1822 	for (i = 0; i < argc; i++) {
1823 		/* Split list of principals */
1824 		n = 0;
1825 		if (cert_principals != NULL) {
1826 			otmp = tmp = xstrdup(cert_principals);
1827 			plist = NULL;
1828 			for (; (cp = strsep(&tmp, ",")) != NULL; n++) {
1829 				plist = xreallocarray(plist, n + 1, sizeof(*plist));
1830 				if (*(plist[n] = xstrdup(cp)) == '\0')
1831 					fatal("Empty principal name");
1832 			}
1833 			free(otmp);
1834 		}
1835 		if (n > SSHKEY_CERT_MAX_PRINCIPALS)
1836 			fatal("Too many certificate principals specified");
1837 
1838 		tmp = tilde_expand_filename(argv[i], pw->pw_uid);
1839 		if ((r = sshkey_load_public(tmp, &public, &comment)) != 0)
1840 			fatal_r(r, "load pubkey \"%s\"", tmp);
1841 		if (sshkey_is_cert(public))
1842 			fatal_f("key \"%s\" type %s cannot be certified",
1843 			    tmp, sshkey_type(public));
1844 
1845 		/* Prepare certificate to sign */
1846 		if ((r = sshkey_to_certified(public)) != 0)
1847 			fatal_r(r, "Could not upgrade key %s to certificate", tmp);
1848 		public->cert->type = cert_key_type;
1849 		public->cert->serial = (u_int64_t)cert_serial;
1850 		public->cert->key_id = xstrdup(cert_key_id);
1851 		public->cert->nprincipals = n;
1852 		public->cert->principals = plist;
1853 		public->cert->valid_after = cert_valid_from;
1854 		public->cert->valid_before = cert_valid_to;
1855 		prepare_options_buf(public->cert->critical, OPTIONS_CRITICAL);
1856 		prepare_options_buf(public->cert->extensions,
1857 		    OPTIONS_EXTENSIONS);
1858 		if ((r = sshkey_from_private(ca,
1859 		    &public->cert->signature_key)) != 0)
1860 			fatal_r(r, "sshkey_from_private (ca key)");
1861 
1862 		if (agent_fd != -1 && (ca->flags & SSHKEY_FLAG_EXT) != 0) {
1863 			if ((r = sshkey_certify_custom(public, ca,
1864 			    key_type_name, sk_provider, NULL, agent_signer,
1865 			    &agent_fd)) != 0)
1866 				fatal_r(r, "Couldn't certify %s via agent", tmp);
1867 		} else {
1868 			if (sshkey_is_sk(ca) &&
1869 			    (ca->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1870 				notifier = notify_start(0,
1871 				    "Confirm user presence for key %s %s",
1872 				    sshkey_type(ca), ca_fp);
1873 			}
1874 			r = sshkey_certify(public, ca, key_type_name,
1875 			    sk_provider, pin);
1876 			notify_complete(notifier, "User presence confirmed");
1877 			if (r != 0)
1878 				fatal_r(r, "Couldn't certify key %s", tmp);
1879 		}
1880 
1881 		if ((cp = strrchr(tmp, '.')) != NULL && strcmp(cp, ".pub") == 0)
1882 			*cp = '\0';
1883 		xasprintf(&out, "%s-cert.pub", tmp);
1884 		free(tmp);
1885 
1886 		if ((r = sshkey_save_public(public, out, comment)) != 0) {
1887 			fatal_r(r, "Unable to save public key to %s",
1888 			    identity_file);
1889 		}
1890 
1891 		if (!quiet) {
1892 			sshkey_format_cert_validity(public->cert,
1893 			    valid, sizeof(valid));
1894 			logit("Signed %s key %s: id \"%s\" serial %llu%s%s "
1895 			    "valid %s", sshkey_cert_type(public),
1896 			    out, public->cert->key_id,
1897 			    (unsigned long long)public->cert->serial,
1898 			    cert_principals != NULL ? " for " : "",
1899 			    cert_principals != NULL ? cert_principals : "",
1900 			    valid);
1901 		}
1902 
1903 		sshkey_free(public);
1904 		free(out);
1905 		if (cert_serial_autoinc)
1906 			cert_serial++;
1907 	}
1908 	if (pin != NULL)
1909 		freezero(pin, strlen(pin));
1910 	free(ca_fp);
1911 #ifdef ENABLE_PKCS11
1912 	pkcs11_terminate();
1913 #endif
1914 	exit(0);
1915 }
1916 
1917 static u_int64_t
1918 parse_relative_time(const char *s, time_t now)
1919 {
1920 	int64_t mul, secs;
1921 
1922 	mul = *s == '-' ? -1 : 1;
1923 
1924 	if ((secs = convtime(s + 1)) == -1)
1925 		fatal("Invalid relative certificate time %s", s);
1926 	if (mul == -1 && secs > now)
1927 		fatal("Certificate time %s cannot be represented", s);
1928 	return now + (u_int64_t)(secs * mul);
1929 }
1930 
1931 static void
1932 parse_hex_u64(const char *s, uint64_t *up)
1933 {
1934 	char *ep;
1935 	unsigned long long ull;
1936 
1937 	errno = 0;
1938 	ull = strtoull(s, &ep, 16);
1939 	if (*s == '\0' || *ep != '\0')
1940 		fatal("Invalid certificate time: not a number");
1941 	if (errno == ERANGE && ull == ULONG_MAX)
1942 		fatal_fr(SSH_ERR_SYSTEM_ERROR, "Invalid certificate time");
1943 	*up = (uint64_t)ull;
1944 }
1945 
1946 static void
1947 parse_cert_times(char *timespec)
1948 {
1949 	char *from, *to;
1950 	time_t now = time(NULL);
1951 	int64_t secs;
1952 
1953 	/* +timespec relative to now */
1954 	if (*timespec == '+' && strchr(timespec, ':') == NULL) {
1955 		if ((secs = convtime(timespec + 1)) == -1)
1956 			fatal("Invalid relative certificate life %s", timespec);
1957 		cert_valid_to = now + secs;
1958 		/*
1959 		 * Backdate certificate one minute to avoid problems on hosts
1960 		 * with poorly-synchronised clocks.
1961 		 */
1962 		cert_valid_from = ((now - 59)/ 60) * 60;
1963 		return;
1964 	}
1965 
1966 	/*
1967 	 * from:to, where
1968 	 * from := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | 0x... | "always"
1969 	 *   to := [+-]timespec | YYYYMMDD | YYYYMMDDHHMMSS | 0x... | "forever"
1970 	 */
1971 	from = xstrdup(timespec);
1972 	to = strchr(from, ':');
1973 	if (to == NULL || from == to || *(to + 1) == '\0')
1974 		fatal("Invalid certificate life specification %s", timespec);
1975 	*to++ = '\0';
1976 
1977 	if (*from == '-' || *from == '+')
1978 		cert_valid_from = parse_relative_time(from, now);
1979 	else if (strcmp(from, "always") == 0)
1980 		cert_valid_from = 0;
1981 	else if (strncmp(from, "0x", 2) == 0)
1982 		parse_hex_u64(from, &cert_valid_from);
1983 	else if (parse_absolute_time(from, &cert_valid_from) != 0)
1984 		fatal("Invalid from time \"%s\"", from);
1985 
1986 	if (*to == '-' || *to == '+')
1987 		cert_valid_to = parse_relative_time(to, now);
1988 	else if (strcmp(to, "forever") == 0)
1989 		cert_valid_to = ~(u_int64_t)0;
1990 	else if (strncmp(to, "0x", 2) == 0)
1991 		parse_hex_u64(to, &cert_valid_to);
1992 	else if (parse_absolute_time(to, &cert_valid_to) != 0)
1993 		fatal("Invalid to time \"%s\"", to);
1994 
1995 	if (cert_valid_to <= cert_valid_from)
1996 		fatal("Empty certificate validity interval");
1997 	free(from);
1998 }
1999 
2000 static void
2001 add_cert_option(char *opt)
2002 {
2003 	char *val, *cp;
2004 	int iscrit = 0;
2005 
2006 	if (strcasecmp(opt, "clear") == 0)
2007 		certflags_flags = 0;
2008 	else if (strcasecmp(opt, "no-x11-forwarding") == 0)
2009 		certflags_flags &= ~CERTOPT_X_FWD;
2010 	else if (strcasecmp(opt, "permit-x11-forwarding") == 0)
2011 		certflags_flags |= CERTOPT_X_FWD;
2012 	else if (strcasecmp(opt, "no-agent-forwarding") == 0)
2013 		certflags_flags &= ~CERTOPT_AGENT_FWD;
2014 	else if (strcasecmp(opt, "permit-agent-forwarding") == 0)
2015 		certflags_flags |= CERTOPT_AGENT_FWD;
2016 	else if (strcasecmp(opt, "no-port-forwarding") == 0)
2017 		certflags_flags &= ~CERTOPT_PORT_FWD;
2018 	else if (strcasecmp(opt, "permit-port-forwarding") == 0)
2019 		certflags_flags |= CERTOPT_PORT_FWD;
2020 	else if (strcasecmp(opt, "no-pty") == 0)
2021 		certflags_flags &= ~CERTOPT_PTY;
2022 	else if (strcasecmp(opt, "permit-pty") == 0)
2023 		certflags_flags |= CERTOPT_PTY;
2024 	else if (strcasecmp(opt, "no-user-rc") == 0)
2025 		certflags_flags &= ~CERTOPT_USER_RC;
2026 	else if (strcasecmp(opt, "permit-user-rc") == 0)
2027 		certflags_flags |= CERTOPT_USER_RC;
2028 	else if (strcasecmp(opt, "touch-required") == 0)
2029 		certflags_flags &= ~CERTOPT_NO_REQUIRE_USER_PRESENCE;
2030 	else if (strcasecmp(opt, "no-touch-required") == 0)
2031 		certflags_flags |= CERTOPT_NO_REQUIRE_USER_PRESENCE;
2032 	else if (strcasecmp(opt, "no-verify-required") == 0)
2033 		certflags_flags &= ~CERTOPT_REQUIRE_VERIFY;
2034 	else if (strcasecmp(opt, "verify-required") == 0)
2035 		certflags_flags |= CERTOPT_REQUIRE_VERIFY;
2036 	else if (strncasecmp(opt, "force-command=", 14) == 0) {
2037 		val = opt + 14;
2038 		if (*val == '\0')
2039 			fatal("Empty force-command option");
2040 		if (certflags_command != NULL)
2041 			fatal("force-command already specified");
2042 		certflags_command = xstrdup(val);
2043 	} else if (strncasecmp(opt, "source-address=", 15) == 0) {
2044 		val = opt + 15;
2045 		if (*val == '\0')
2046 			fatal("Empty source-address option");
2047 		if (certflags_src_addr != NULL)
2048 			fatal("source-address already specified");
2049 		if (addr_match_cidr_list(NULL, val) != 0)
2050 			fatal("Invalid source-address list");
2051 		certflags_src_addr = xstrdup(val);
2052 	} else if (strncasecmp(opt, "extension:", 10) == 0 ||
2053 		    (iscrit = (strncasecmp(opt, "critical:", 9) == 0))) {
2054 		val = xstrdup(strchr(opt, ':') + 1);
2055 		if ((cp = strchr(val, '=')) != NULL)
2056 			*cp++ = '\0';
2057 		cert_ext_add(val, cp, iscrit);
2058 		free(val);
2059 	} else
2060 		fatal("Unsupported certificate option \"%s\"", opt);
2061 }
2062 
2063 static void
2064 show_options(struct sshbuf *optbuf, int in_critical)
2065 {
2066 	char *name, *arg, *hex;
2067 	struct sshbuf *options, *option = NULL;
2068 	int r;
2069 
2070 	if ((options = sshbuf_fromb(optbuf)) == NULL)
2071 		fatal_f("sshbuf_fromb failed");
2072 	while (sshbuf_len(options) != 0) {
2073 		sshbuf_free(option);
2074 		option = NULL;
2075 		if ((r = sshbuf_get_cstring(options, &name, NULL)) != 0 ||
2076 		    (r = sshbuf_froms(options, &option)) != 0)
2077 			fatal_fr(r, "parse option");
2078 		printf("                %s", name);
2079 		if (!in_critical &&
2080 		    (strcmp(name, "permit-X11-forwarding") == 0 ||
2081 		    strcmp(name, "permit-agent-forwarding") == 0 ||
2082 		    strcmp(name, "permit-port-forwarding") == 0 ||
2083 		    strcmp(name, "permit-pty") == 0 ||
2084 		    strcmp(name, "permit-user-rc") == 0 ||
2085 		    strcmp(name, "no-touch-required") == 0)) {
2086 			printf("\n");
2087 		} else if (in_critical &&
2088 		    (strcmp(name, "force-command") == 0 ||
2089 		    strcmp(name, "source-address") == 0)) {
2090 			if ((r = sshbuf_get_cstring(option, &arg, NULL)) != 0)
2091 				fatal_fr(r, "parse critical");
2092 			printf(" %s\n", arg);
2093 			free(arg);
2094 		} else if (in_critical &&
2095 		    strcmp(name, "verify-required") == 0) {
2096 			printf("\n");
2097 		} else if (sshbuf_len(option) > 0) {
2098 			hex = sshbuf_dtob16(option);
2099 			printf(" UNKNOWN OPTION: %s (len %zu)\n",
2100 			    hex, sshbuf_len(option));
2101 			sshbuf_reset(option);
2102 			free(hex);
2103 		} else
2104 			printf(" UNKNOWN FLAG OPTION\n");
2105 		free(name);
2106 		if (sshbuf_len(option) != 0)
2107 			fatal("Option corrupt: extra data at end");
2108 	}
2109 	sshbuf_free(option);
2110 	sshbuf_free(options);
2111 }
2112 
2113 static void
2114 print_cert(struct sshkey *key)
2115 {
2116 	char valid[64], *key_fp, *ca_fp;
2117 	u_int i;
2118 
2119 	key_fp = sshkey_fingerprint(key, fingerprint_hash, SSH_FP_DEFAULT);
2120 	ca_fp = sshkey_fingerprint(key->cert->signature_key,
2121 	    fingerprint_hash, SSH_FP_DEFAULT);
2122 	if (key_fp == NULL || ca_fp == NULL)
2123 		fatal_f("sshkey_fingerprint fail");
2124 	sshkey_format_cert_validity(key->cert, valid, sizeof(valid));
2125 
2126 	printf("        Type: %s %s certificate\n", sshkey_ssh_name(key),
2127 	    sshkey_cert_type(key));
2128 	printf("        Public key: %s %s\n", sshkey_type(key), key_fp);
2129 	printf("        Signing CA: %s %s (using %s)\n",
2130 	    sshkey_type(key->cert->signature_key), ca_fp,
2131 	    key->cert->signature_type);
2132 	printf("        Key ID: \"%s\"\n", key->cert->key_id);
2133 	printf("        Serial: %llu\n", (unsigned long long)key->cert->serial);
2134 	printf("        Valid: %s\n", valid);
2135 	printf("        Principals: ");
2136 	if (key->cert->nprincipals == 0)
2137 		printf("(none)\n");
2138 	else {
2139 		for (i = 0; i < key->cert->nprincipals; i++)
2140 			printf("\n                %s",
2141 			    key->cert->principals[i]);
2142 		printf("\n");
2143 	}
2144 	printf("        Critical Options: ");
2145 	if (sshbuf_len(key->cert->critical) == 0)
2146 		printf("(none)\n");
2147 	else {
2148 		printf("\n");
2149 		show_options(key->cert->critical, 1);
2150 	}
2151 	printf("        Extensions: ");
2152 	if (sshbuf_len(key->cert->extensions) == 0)
2153 		printf("(none)\n");
2154 	else {
2155 		printf("\n");
2156 		show_options(key->cert->extensions, 0);
2157 	}
2158 }
2159 
2160 static void
2161 do_show_cert(struct passwd *pw)
2162 {
2163 	struct sshkey *key = NULL;
2164 	struct stat st;
2165 	int r, is_stdin = 0, ok = 0;
2166 	FILE *f;
2167 	char *cp, *line = NULL;
2168 	const char *path;
2169 	size_t linesize = 0;
2170 	u_long lnum = 0;
2171 
2172 	if (!have_identity)
2173 		ask_filename(pw, "Enter file in which the key is");
2174 	if (strcmp(identity_file, "-") != 0 && stat(identity_file, &st) == -1)
2175 		fatal("%s: %s: %s", __progname, identity_file, strerror(errno));
2176 
2177 	path = identity_file;
2178 	if (strcmp(path, "-") == 0) {
2179 		f = stdin;
2180 		path = "(stdin)";
2181 		is_stdin = 1;
2182 	} else if ((f = fopen(identity_file, "r")) == NULL)
2183 		fatal("fopen %s: %s", identity_file, strerror(errno));
2184 
2185 	while (getline(&line, &linesize, f) != -1) {
2186 		lnum++;
2187 		sshkey_free(key);
2188 		key = NULL;
2189 		/* Trim leading space and comments */
2190 		cp = line + strspn(line, " \t");
2191 		if (*cp == '#' || *cp == '\0')
2192 			continue;
2193 		if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2194 			fatal("sshkey_new");
2195 		if ((r = sshkey_read(key, &cp)) != 0) {
2196 			error_r(r, "%s:%lu: invalid key", path, lnum);
2197 			continue;
2198 		}
2199 		if (!sshkey_is_cert(key)) {
2200 			error("%s:%lu is not a certificate", path, lnum);
2201 			continue;
2202 		}
2203 		ok = 1;
2204 		if (!is_stdin && lnum == 1)
2205 			printf("%s:\n", path);
2206 		else
2207 			printf("%s:%lu:\n", path, lnum);
2208 		print_cert(key);
2209 	}
2210 	free(line);
2211 	sshkey_free(key);
2212 	fclose(f);
2213 	exit(ok ? 0 : 1);
2214 }
2215 
2216 static void
2217 load_krl(const char *path, struct ssh_krl **krlp)
2218 {
2219 	struct sshbuf *krlbuf;
2220 	int r;
2221 
2222 	if ((r = sshbuf_load_file(path, &krlbuf)) != 0)
2223 		fatal_r(r, "Unable to load KRL %s", path);
2224 	/* XXX check sigs */
2225 	if ((r = ssh_krl_from_blob(krlbuf, krlp, NULL, 0)) != 0 ||
2226 	    *krlp == NULL)
2227 		fatal_r(r, "Invalid KRL file %s", path);
2228 	sshbuf_free(krlbuf);
2229 }
2230 
2231 static void
2232 hash_to_blob(const char *cp, u_char **blobp, size_t *lenp,
2233     const char *file, u_long lnum)
2234 {
2235 	char *tmp;
2236 	size_t tlen;
2237 	struct sshbuf *b;
2238 	int r;
2239 
2240 	if (strncmp(cp, "SHA256:", 7) != 0)
2241 		fatal("%s:%lu: unsupported hash algorithm", file, lnum);
2242 	cp += 7;
2243 
2244 	/*
2245 	 * OpenSSH base64 hashes omit trailing '='
2246 	 * characters; put them back for decode.
2247 	 */
2248 	tlen = strlen(cp);
2249 	tmp = xmalloc(tlen + 4 + 1);
2250 	strlcpy(tmp, cp, tlen + 1);
2251 	while ((tlen % 4) != 0) {
2252 		tmp[tlen++] = '=';
2253 		tmp[tlen] = '\0';
2254 	}
2255 	if ((b = sshbuf_new()) == NULL)
2256 		fatal_f("sshbuf_new failed");
2257 	if ((r = sshbuf_b64tod(b, tmp)) != 0)
2258 		fatal_r(r, "%s:%lu: decode hash failed", file, lnum);
2259 	free(tmp);
2260 	*lenp = sshbuf_len(b);
2261 	*blobp = xmalloc(*lenp);
2262 	memcpy(*blobp, sshbuf_ptr(b), *lenp);
2263 	sshbuf_free(b);
2264 }
2265 
2266 static void
2267 update_krl_from_file(struct passwd *pw, const char *file, int wild_ca,
2268     const struct sshkey *ca, struct ssh_krl *krl)
2269 {
2270 	struct sshkey *key = NULL;
2271 	u_long lnum = 0;
2272 	char *path, *cp, *ep, *line = NULL;
2273 	u_char *blob = NULL;
2274 	size_t blen = 0, linesize = 0;
2275 	unsigned long long serial, serial2;
2276 	int i, was_explicit_key, was_sha1, was_sha256, was_hash, r;
2277 	FILE *krl_spec;
2278 
2279 	path = tilde_expand_filename(file, pw->pw_uid);
2280 	if (strcmp(path, "-") == 0) {
2281 		krl_spec = stdin;
2282 		free(path);
2283 		path = xstrdup("(standard input)");
2284 	} else if ((krl_spec = fopen(path, "r")) == NULL)
2285 		fatal("fopen %s: %s", path, strerror(errno));
2286 
2287 	if (!quiet)
2288 		printf("Revoking from %s\n", path);
2289 	while (getline(&line, &linesize, krl_spec) != -1) {
2290 		lnum++;
2291 		was_explicit_key = was_sha1 = was_sha256 = was_hash = 0;
2292 		cp = line + strspn(line, " \t");
2293 		/* Trim trailing space, comments and strip \n */
2294 		for (i = 0, r = -1; cp[i] != '\0'; i++) {
2295 			if (cp[i] == '#' || cp[i] == '\n') {
2296 				cp[i] = '\0';
2297 				break;
2298 			}
2299 			if (cp[i] == ' ' || cp[i] == '\t') {
2300 				/* Remember the start of a span of whitespace */
2301 				if (r == -1)
2302 					r = i;
2303 			} else
2304 				r = -1;
2305 		}
2306 		if (r != -1)
2307 			cp[r] = '\0';
2308 		if (*cp == '\0')
2309 			continue;
2310 		if (strncasecmp(cp, "serial:", 7) == 0) {
2311 			if (ca == NULL && !wild_ca) {
2312 				fatal("revoking certificates by serial number "
2313 				    "requires specification of a CA key");
2314 			}
2315 			cp += 7;
2316 			cp = cp + strspn(cp, " \t");
2317 			errno = 0;
2318 			serial = strtoull(cp, &ep, 0);
2319 			if (*cp == '\0' || (*ep != '\0' && *ep != '-'))
2320 				fatal("%s:%lu: invalid serial \"%s\"",
2321 				    path, lnum, cp);
2322 			if (errno == ERANGE && serial == ULLONG_MAX)
2323 				fatal("%s:%lu: serial out of range",
2324 				    path, lnum);
2325 			serial2 = serial;
2326 			if (*ep == '-') {
2327 				cp = ep + 1;
2328 				errno = 0;
2329 				serial2 = strtoull(cp, &ep, 0);
2330 				if (*cp == '\0' || *ep != '\0')
2331 					fatal("%s:%lu: invalid serial \"%s\"",
2332 					    path, lnum, cp);
2333 				if (errno == ERANGE && serial2 == ULLONG_MAX)
2334 					fatal("%s:%lu: serial out of range",
2335 					    path, lnum);
2336 				if (serial2 <= serial)
2337 					fatal("%s:%lu: invalid serial range "
2338 					    "%llu:%llu", path, lnum,
2339 					    (unsigned long long)serial,
2340 					    (unsigned long long)serial2);
2341 			}
2342 			if (ssh_krl_revoke_cert_by_serial_range(krl,
2343 			    ca, serial, serial2) != 0) {
2344 				fatal_f("revoke serial failed");
2345 			}
2346 		} else if (strncasecmp(cp, "id:", 3) == 0) {
2347 			if (ca == NULL && !wild_ca) {
2348 				fatal("revoking certificates by key ID "
2349 				    "requires specification of a CA key");
2350 			}
2351 			cp += 3;
2352 			cp = cp + strspn(cp, " \t");
2353 			if (ssh_krl_revoke_cert_by_key_id(krl, ca, cp) != 0)
2354 				fatal_f("revoke key ID failed");
2355 		} else if (strncasecmp(cp, "hash:", 5) == 0) {
2356 			cp += 5;
2357 			cp = cp + strspn(cp, " \t");
2358 			hash_to_blob(cp, &blob, &blen, file, lnum);
2359 			r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2360 			if (r != 0)
2361 				fatal_fr(r, "revoke key failed");
2362 		} else {
2363 			if (strncasecmp(cp, "key:", 4) == 0) {
2364 				cp += 4;
2365 				cp = cp + strspn(cp, " \t");
2366 				was_explicit_key = 1;
2367 			} else if (strncasecmp(cp, "sha1:", 5) == 0) {
2368 				cp += 5;
2369 				cp = cp + strspn(cp, " \t");
2370 				was_sha1 = 1;
2371 			} else if (strncasecmp(cp, "sha256:", 7) == 0) {
2372 				cp += 7;
2373 				cp = cp + strspn(cp, " \t");
2374 				was_sha256 = 1;
2375 				/*
2376 				 * Just try to process the line as a key.
2377 				 * Parsing will fail if it isn't.
2378 				 */
2379 			}
2380 			if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
2381 				fatal("sshkey_new");
2382 			if ((r = sshkey_read(key, &cp)) != 0)
2383 				fatal_r(r, "%s:%lu: invalid key", path, lnum);
2384 			if (was_explicit_key)
2385 				r = ssh_krl_revoke_key_explicit(krl, key);
2386 			else if (was_sha1) {
2387 				if (sshkey_fingerprint_raw(key,
2388 				    SSH_DIGEST_SHA1, &blob, &blen) != 0) {
2389 					fatal("%s:%lu: fingerprint failed",
2390 					    file, lnum);
2391 				}
2392 				r = ssh_krl_revoke_key_sha1(krl, blob, blen);
2393 			} else if (was_sha256) {
2394 				if (sshkey_fingerprint_raw(key,
2395 				    SSH_DIGEST_SHA256, &blob, &blen) != 0) {
2396 					fatal("%s:%lu: fingerprint failed",
2397 					    file, lnum);
2398 				}
2399 				r = ssh_krl_revoke_key_sha256(krl, blob, blen);
2400 			} else
2401 				r = ssh_krl_revoke_key(krl, key);
2402 			if (r != 0)
2403 				fatal_fr(r, "revoke key failed");
2404 			freezero(blob, blen);
2405 			blob = NULL;
2406 			blen = 0;
2407 			sshkey_free(key);
2408 		}
2409 	}
2410 	if (strcmp(path, "-") != 0)
2411 		fclose(krl_spec);
2412 	free(line);
2413 	free(path);
2414 }
2415 
2416 static void
2417 do_gen_krl(struct passwd *pw, int updating, const char *ca_key_path,
2418     unsigned long long krl_version, const char *krl_comment,
2419     int argc, char **argv)
2420 {
2421 	struct ssh_krl *krl;
2422 	struct stat sb;
2423 	struct sshkey *ca = NULL;
2424 	int i, r, wild_ca = 0;
2425 	char *tmp;
2426 	struct sshbuf *kbuf;
2427 
2428 	if (*identity_file == '\0')
2429 		fatal("KRL generation requires an output file");
2430 	if (stat(identity_file, &sb) == -1) {
2431 		if (errno != ENOENT)
2432 			fatal("Cannot access KRL \"%s\": %s",
2433 			    identity_file, strerror(errno));
2434 		if (updating)
2435 			fatal("KRL \"%s\" does not exist", identity_file);
2436 	}
2437 	if (ca_key_path != NULL) {
2438 		if (strcasecmp(ca_key_path, "none") == 0)
2439 			wild_ca = 1;
2440 		else {
2441 			tmp = tilde_expand_filename(ca_key_path, pw->pw_uid);
2442 			if ((r = sshkey_load_public(tmp, &ca, NULL)) != 0)
2443 				fatal_r(r, "Cannot load CA public key %s", tmp);
2444 			free(tmp);
2445 		}
2446 	}
2447 
2448 	if (updating)
2449 		load_krl(identity_file, &krl);
2450 	else if ((krl = ssh_krl_init()) == NULL)
2451 		fatal("couldn't create KRL");
2452 
2453 	if (krl_version != 0)
2454 		ssh_krl_set_version(krl, krl_version);
2455 	if (krl_comment != NULL)
2456 		ssh_krl_set_comment(krl, krl_comment);
2457 
2458 	for (i = 0; i < argc; i++)
2459 		update_krl_from_file(pw, argv[i], wild_ca, ca, krl);
2460 
2461 	if ((kbuf = sshbuf_new()) == NULL)
2462 		fatal("sshbuf_new failed");
2463 	if (ssh_krl_to_blob(krl, kbuf, NULL, 0) != 0)
2464 		fatal("Couldn't generate KRL");
2465 	if ((r = sshbuf_write_file(identity_file, kbuf)) != 0)
2466 		fatal("write %s: %s", identity_file, strerror(errno));
2467 	sshbuf_free(kbuf);
2468 	ssh_krl_free(krl);
2469 	sshkey_free(ca);
2470 }
2471 
2472 static void
2473 do_check_krl(struct passwd *pw, int print_krl, int argc, char **argv)
2474 {
2475 	int i, r, ret = 0;
2476 	char *comment;
2477 	struct ssh_krl *krl;
2478 	struct sshkey *k;
2479 
2480 	if (*identity_file == '\0')
2481 		fatal("KRL checking requires an input file");
2482 	load_krl(identity_file, &krl);
2483 	if (print_krl)
2484 		krl_dump(krl, stdout);
2485 	for (i = 0; i < argc; i++) {
2486 		if ((r = sshkey_load_public(argv[i], &k, &comment)) != 0)
2487 			fatal_r(r, "Cannot load public key %s", argv[i]);
2488 		r = ssh_krl_check_key(krl, k);
2489 		printf("%s%s%s%s: %s\n", argv[i],
2490 		    *comment ? " (" : "", comment, *comment ? ")" : "",
2491 		    r == 0 ? "ok" : "REVOKED");
2492 		if (r != 0)
2493 			ret = 1;
2494 		sshkey_free(k);
2495 		free(comment);
2496 	}
2497 	ssh_krl_free(krl);
2498 	exit(ret);
2499 }
2500 
2501 static struct sshkey *
2502 load_sign_key(const char *keypath, const struct sshkey *pubkey)
2503 {
2504 	size_t i, slen, plen = strlen(keypath);
2505 	char *privpath = xstrdup(keypath);
2506 	static const char * const suffixes[] = { "-cert.pub", ".pub", NULL };
2507 	struct sshkey *ret = NULL, *privkey = NULL;
2508 	int r, waspub = 0;
2509 	struct stat st;
2510 
2511 	/*
2512 	 * If passed a public key filename, then try to locate the corresponding
2513 	 * private key. This lets us specify certificates on the command-line
2514 	 * and have ssh-keygen find the appropriate private key.
2515 	 */
2516 	for (i = 0; suffixes[i]; i++) {
2517 		slen = strlen(suffixes[i]);
2518 		if (plen <= slen ||
2519 		    strcmp(privpath + plen - slen, suffixes[i]) != 0)
2520 			continue;
2521 		privpath[plen - slen] = '\0';
2522 		debug_f("%s looks like a public key, using private key "
2523 		    "path %s instead", keypath, privpath);
2524 		waspub = 1;
2525 	}
2526 	if (waspub && stat(privpath, &st) != 0 && errno == ENOENT)
2527 		fatal("No private key found for public key \"%s\"", keypath);
2528 	if ((r = sshkey_load_private(privpath, "", &privkey, NULL)) != 0 &&
2529 	    (r != SSH_ERR_KEY_WRONG_PASSPHRASE)) {
2530 		debug_fr(r, "load private key \"%s\"", privpath);
2531 		fatal("No private key found for \"%s\"", privpath);
2532 	} else if (privkey == NULL)
2533 		privkey = load_identity(privpath, NULL);
2534 
2535 	if (!sshkey_equal_public(pubkey, privkey)) {
2536 		error("Public key %s doesn't match private %s",
2537 		    keypath, privpath);
2538 		goto done;
2539 	}
2540 	if (sshkey_is_cert(pubkey) && !sshkey_is_cert(privkey)) {
2541 		/*
2542 		 * Graft the certificate onto the private key to make
2543 		 * it capable of signing.
2544 		 */
2545 		if ((r = sshkey_to_certified(privkey)) != 0) {
2546 			error_fr(r, "sshkey_to_certified");
2547 			goto done;
2548 		}
2549 		if ((r = sshkey_cert_copy(pubkey, privkey)) != 0) {
2550 			error_fr(r, "sshkey_cert_copy");
2551 			goto done;
2552 		}
2553 	}
2554 	/* success */
2555 	ret = privkey;
2556 	privkey = NULL;
2557  done:
2558 	sshkey_free(privkey);
2559 	free(privpath);
2560 	return ret;
2561 }
2562 
2563 static int
2564 sign_one(struct sshkey *signkey, const char *filename, int fd,
2565     const char *sig_namespace, const char *hashalg, sshsig_signer *signer,
2566     void *signer_ctx)
2567 {
2568 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2569 	int r = SSH_ERR_INTERNAL_ERROR, wfd = -1, oerrno;
2570 	char *wfile = NULL, *asig = NULL, *fp = NULL;
2571 	char *pin = NULL, *prompt = NULL;
2572 
2573 	if (!quiet) {
2574 		if (fd == STDIN_FILENO)
2575 			fprintf(stderr, "Signing data on standard input\n");
2576 		else
2577 			fprintf(stderr, "Signing file %s\n", filename);
2578 	}
2579 	if (signer == NULL && sshkey_is_sk(signkey)) {
2580 		if ((signkey->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
2581 			xasprintf(&prompt, "Enter PIN for %s key: ",
2582 			    sshkey_type(signkey));
2583 			if ((pin = read_passphrase(prompt,
2584 			    RP_ALLOW_STDIN)) == NULL)
2585 				fatal_f("couldn't read PIN");
2586 		}
2587 		if ((signkey->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
2588 			if ((fp = sshkey_fingerprint(signkey, fingerprint_hash,
2589 			    SSH_FP_DEFAULT)) == NULL)
2590 				fatal_f("fingerprint failed");
2591 			fprintf(stderr, "Confirm user presence for key %s %s\n",
2592 			    sshkey_type(signkey), fp);
2593 			free(fp);
2594 		}
2595 	}
2596 	if ((r = sshsig_sign_fd(signkey, hashalg, sk_provider, pin,
2597 	    fd, sig_namespace, &sigbuf, signer, signer_ctx)) != 0) {
2598 		error_r(r, "Signing %s failed", filename);
2599 		goto out;
2600 	}
2601 	if ((r = sshsig_armor(sigbuf, &abuf)) != 0) {
2602 		error_fr(r, "sshsig_armor");
2603 		goto out;
2604 	}
2605 	if ((asig = sshbuf_dup_string(abuf)) == NULL) {
2606 		error_f("buffer error");
2607 		r = SSH_ERR_ALLOC_FAIL;
2608 		goto out;
2609 	}
2610 
2611 	if (fd == STDIN_FILENO) {
2612 		fputs(asig, stdout);
2613 		fflush(stdout);
2614 	} else {
2615 		xasprintf(&wfile, "%s.sig", filename);
2616 		if (confirm_overwrite(wfile)) {
2617 			if ((wfd = open(wfile, O_WRONLY|O_CREAT|O_TRUNC,
2618 			    0666)) == -1) {
2619 				oerrno = errno;
2620 				error("Cannot open %s: %s",
2621 				    wfile, strerror(errno));
2622 				errno = oerrno;
2623 				r = SSH_ERR_SYSTEM_ERROR;
2624 				goto out;
2625 			}
2626 			if (atomicio(vwrite, wfd, asig,
2627 			    strlen(asig)) != strlen(asig)) {
2628 				oerrno = errno;
2629 				error("Cannot write to %s: %s",
2630 				    wfile, strerror(errno));
2631 				errno = oerrno;
2632 				r = SSH_ERR_SYSTEM_ERROR;
2633 				goto out;
2634 			}
2635 			if (!quiet) {
2636 				fprintf(stderr, "Write signature to %s\n",
2637 				    wfile);
2638 			}
2639 		}
2640 	}
2641 	/* success */
2642 	r = 0;
2643  out:
2644 	free(wfile);
2645 	free(prompt);
2646 	free(asig);
2647 	if (pin != NULL)
2648 		freezero(pin, strlen(pin));
2649 	sshbuf_free(abuf);
2650 	sshbuf_free(sigbuf);
2651 	if (wfd != -1)
2652 		close(wfd);
2653 	return r;
2654 }
2655 
2656 static int
2657 sig_process_opts(char * const *opts, size_t nopts, char **hashalgp,
2658     uint64_t *verify_timep, int *print_pubkey)
2659 {
2660 	size_t i;
2661 	time_t now;
2662 
2663 	if (verify_timep != NULL)
2664 		*verify_timep = 0;
2665 	if (print_pubkey != NULL)
2666 		*print_pubkey = 0;
2667 	if (hashalgp != NULL)
2668 		*hashalgp = NULL;
2669 	for (i = 0; i < nopts; i++) {
2670 		if (hashalgp != NULL &&
2671 		    strncasecmp(opts[i], "hashalg=", 8) == 0) {
2672 			*hashalgp = xstrdup(opts[i] + 8);
2673 		} else if (verify_timep &&
2674 		    strncasecmp(opts[i], "verify-time=", 12) == 0) {
2675 			if (parse_absolute_time(opts[i] + 12,
2676 			    verify_timep) != 0 || *verify_timep == 0) {
2677 				error("Invalid \"verify-time\" option");
2678 				return SSH_ERR_INVALID_ARGUMENT;
2679 			}
2680 		} else if (print_pubkey &&
2681 		    strcasecmp(opts[i], "print-pubkey") == 0) {
2682 			*print_pubkey = 1;
2683 		} else {
2684 			error("Invalid option \"%s\"", opts[i]);
2685 			return SSH_ERR_INVALID_ARGUMENT;
2686 		}
2687 	}
2688 	if (verify_timep && *verify_timep == 0) {
2689 		if ((now = time(NULL)) < 0) {
2690 			error("Time is before epoch");
2691 			return SSH_ERR_INVALID_ARGUMENT;
2692 		}
2693 		*verify_timep = (uint64_t)now;
2694 	}
2695 	return 0;
2696 }
2697 
2698 
2699 static int
2700 sig_sign(const char *keypath, const char *sig_namespace, int require_agent,
2701     int argc, char **argv, char * const *opts, size_t nopts)
2702 {
2703 	int i, fd = -1, r, ret = -1;
2704 	int agent_fd = -1;
2705 	struct sshkey *pubkey = NULL, *privkey = NULL, *signkey = NULL;
2706 	sshsig_signer *signer = NULL;
2707 	char *hashalg = NULL;
2708 
2709 	/* Check file arguments. */
2710 	for (i = 0; i < argc; i++) {
2711 		if (strcmp(argv[i], "-") != 0)
2712 			continue;
2713 		if (i > 0 || argc > 1)
2714 			fatal("Cannot sign mix of paths and standard input");
2715 	}
2716 
2717 	if (sig_process_opts(opts, nopts, &hashalg, NULL, NULL) != 0)
2718 		goto done; /* error already logged */
2719 
2720 	if ((r = sshkey_load_public(keypath, &pubkey, NULL)) != 0) {
2721 		error_r(r, "Couldn't load public key %s", keypath);
2722 		goto done;
2723 	}
2724 
2725 	if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
2726 		if (require_agent)
2727 			fatal("Couldn't get agent socket");
2728 		debug_r(r, "Couldn't get agent socket");
2729 	} else {
2730 		if ((r = ssh_agent_has_key(agent_fd, pubkey)) == 0)
2731 			signer = agent_signer;
2732 		else {
2733 			if (require_agent)
2734 				fatal("Couldn't find key in agent");
2735 			debug_r(r, "Couldn't find key in agent");
2736 		}
2737 	}
2738 
2739 	if (signer == NULL) {
2740 		/* Not using agent - try to load private key */
2741 		if ((privkey = load_sign_key(keypath, pubkey)) == NULL)
2742 			goto done;
2743 		signkey = privkey;
2744 	} else {
2745 		/* Will use key in agent */
2746 		signkey = pubkey;
2747 	}
2748 
2749 	if (argc == 0) {
2750 		if ((r = sign_one(signkey, "(stdin)", STDIN_FILENO,
2751 		    sig_namespace, hashalg, signer, &agent_fd)) != 0)
2752 			goto done;
2753 	} else {
2754 		for (i = 0; i < argc; i++) {
2755 			if (strcmp(argv[i], "-") == 0)
2756 				fd = STDIN_FILENO;
2757 			else if ((fd = open(argv[i], O_RDONLY)) == -1) {
2758 				error("Cannot open %s for signing: %s",
2759 				    argv[i], strerror(errno));
2760 				goto done;
2761 			}
2762 			if ((r = sign_one(signkey, argv[i], fd, sig_namespace,
2763 			    hashalg, signer, &agent_fd)) != 0)
2764 				goto done;
2765 			if (fd != STDIN_FILENO)
2766 				close(fd);
2767 			fd = -1;
2768 		}
2769 	}
2770 
2771 	ret = 0;
2772 done:
2773 	if (fd != -1 && fd != STDIN_FILENO)
2774 		close(fd);
2775 	sshkey_free(pubkey);
2776 	sshkey_free(privkey);
2777 	free(hashalg);
2778 	return ret;
2779 }
2780 
2781 static int
2782 sig_verify(const char *signature, const char *sig_namespace,
2783     const char *principal, const char *allowed_keys, const char *revoked_keys,
2784     char * const *opts, size_t nopts)
2785 {
2786 	int r, ret = -1;
2787 	int print_pubkey = 0;
2788 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2789 	struct sshkey *sign_key = NULL;
2790 	char *fp = NULL;
2791 	struct sshkey_sig_details *sig_details = NULL;
2792 	uint64_t verify_time = 0;
2793 
2794 	if (sig_process_opts(opts, nopts, NULL, &verify_time,
2795 	    &print_pubkey) != 0)
2796 		goto done; /* error already logged */
2797 
2798 	memset(&sig_details, 0, sizeof(sig_details));
2799 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2800 		error_r(r, "Couldn't read signature file");
2801 		goto done;
2802 	}
2803 
2804 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2805 		error_fr(r, "sshsig_armor");
2806 		goto done;
2807 	}
2808 	if ((r = sshsig_verify_fd(sigbuf, STDIN_FILENO, sig_namespace,
2809 	    &sign_key, &sig_details)) != 0)
2810 		goto done; /* sshsig_verify() prints error */
2811 
2812 	if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2813 	    SSH_FP_DEFAULT)) == NULL)
2814 		fatal_f("sshkey_fingerprint failed");
2815 	debug("Valid (unverified) signature from key %s", fp);
2816 	if (sig_details != NULL) {
2817 		debug2_f("signature details: counter = %u, flags = 0x%02x",
2818 		    sig_details->sk_counter, sig_details->sk_flags);
2819 	}
2820 	free(fp);
2821 	fp = NULL;
2822 
2823 	if (revoked_keys != NULL) {
2824 		if ((r = sshkey_check_revoked(sign_key, revoked_keys)) != 0) {
2825 			debug3_fr(r, "sshkey_check_revoked");
2826 			goto done;
2827 		}
2828 	}
2829 
2830 	if (allowed_keys != NULL && (r = sshsig_check_allowed_keys(allowed_keys,
2831 	    sign_key, principal, sig_namespace, verify_time)) != 0) {
2832 		debug3_fr(r, "sshsig_check_allowed_keys");
2833 		goto done;
2834 	}
2835 	/* success */
2836 	ret = 0;
2837 done:
2838 	if (!quiet) {
2839 		if (ret == 0) {
2840 			if ((fp = sshkey_fingerprint(sign_key, fingerprint_hash,
2841 			    SSH_FP_DEFAULT)) == NULL)
2842 				fatal_f("sshkey_fingerprint failed");
2843 			if (principal == NULL) {
2844 				printf("Good \"%s\" signature with %s key %s\n",
2845 				    sig_namespace, sshkey_type(sign_key), fp);
2846 
2847 			} else {
2848 				printf("Good \"%s\" signature for %s with %s key %s\n",
2849 				    sig_namespace, principal,
2850 				    sshkey_type(sign_key), fp);
2851 			}
2852 		} else {
2853 			printf("Could not verify signature.\n");
2854 		}
2855 	}
2856 	/* Print the signature key if requested */
2857 	if (ret == 0 && print_pubkey && sign_key != NULL) {
2858 		if ((r = sshkey_write(sign_key, stdout)) == 0)
2859 			fputc('\n', stdout);
2860 		else {
2861 			error_r(r, "Could not print public key.\n");
2862 			ret = -1;
2863 		}
2864 	}
2865 	sshbuf_free(sigbuf);
2866 	sshbuf_free(abuf);
2867 	sshkey_free(sign_key);
2868 	sshkey_sig_details_free(sig_details);
2869 	free(fp);
2870 	return ret;
2871 }
2872 
2873 static int
2874 sig_find_principals(const char *signature, const char *allowed_keys,
2875     char * const *opts, size_t nopts)
2876 {
2877 	int r, ret = -1;
2878 	struct sshbuf *sigbuf = NULL, *abuf = NULL;
2879 	struct sshkey *sign_key = NULL;
2880 	char *principals = NULL, *cp, *tmp;
2881 	uint64_t verify_time = 0;
2882 
2883 	if (sig_process_opts(opts, nopts, NULL, &verify_time, NULL) != 0)
2884 		goto done; /* error already logged */
2885 
2886 	if ((r = sshbuf_load_file(signature, &abuf)) != 0) {
2887 		error_r(r, "Couldn't read signature file");
2888 		goto done;
2889 	}
2890 	if ((r = sshsig_dearmor(abuf, &sigbuf)) != 0) {
2891 		error_fr(r, "sshsig_armor");
2892 		goto done;
2893 	}
2894 	if ((r = sshsig_get_pubkey(sigbuf, &sign_key)) != 0) {
2895 		error_fr(r, "sshsig_get_pubkey");
2896 		goto done;
2897 	}
2898 	if ((r = sshsig_find_principals(allowed_keys, sign_key,
2899 	    verify_time, &principals)) != 0) {
2900 		if (r != SSH_ERR_KEY_NOT_FOUND)
2901 			error_fr(r, "sshsig_find_principal");
2902 		goto done;
2903 	}
2904 	ret = 0;
2905 done:
2906 	if (ret == 0 ) {
2907 		/* Emit matching principals one per line */
2908 		tmp = principals;
2909 		while ((cp = strsep(&tmp, ",")) != NULL && *cp != '\0')
2910 			puts(cp);
2911 	} else {
2912 		fprintf(stderr, "No principal matched.\n");
2913 	}
2914 	sshbuf_free(sigbuf);
2915 	sshbuf_free(abuf);
2916 	sshkey_free(sign_key);
2917 	free(principals);
2918 	return ret;
2919 }
2920 
2921 static int
2922 sig_match_principals(const char *allowed_keys, char *principal,
2923 	char * const *opts, size_t nopts)
2924 {
2925 	int r;
2926 	char **principals = NULL;
2927 	size_t i, nprincipals = 0;
2928 
2929 	if ((r = sig_process_opts(opts, nopts, NULL, NULL, NULL)) != 0)
2930 		return r; /* error already logged */
2931 
2932 	if ((r = sshsig_match_principals(allowed_keys, principal,
2933 	    &principals, &nprincipals)) != 0) {
2934 		debug_f("match: %s", ssh_err(r));
2935 		fprintf(stderr, "No principal matched.\n");
2936 		return r;
2937 	}
2938 	for (i = 0; i < nprincipals; i++) {
2939 		printf("%s\n", principals[i]);
2940 		free(principals[i]);
2941 	}
2942 	free(principals);
2943 
2944 	return 0;
2945 }
2946 
2947 static void
2948 do_moduli_gen(const char *out_file, char **opts, size_t nopts)
2949 {
2950 #ifdef WITH_OPENSSL
2951 	/* Moduli generation/screening */
2952 	u_int32_t memory = 0;
2953 	BIGNUM *start = NULL;
2954 	int moduli_bits = 0;
2955 	FILE *out;
2956 	size_t i;
2957 	const char *errstr;
2958 
2959 	/* Parse options */
2960 	for (i = 0; i < nopts; i++) {
2961 		if (strncmp(opts[i], "memory=", 7) == 0) {
2962 			memory = (u_int32_t)strtonum(opts[i]+7, 1,
2963 			    UINT_MAX, &errstr);
2964 			if (errstr) {
2965 				fatal("Memory limit is %s: %s",
2966 				    errstr, opts[i]+7);
2967 			}
2968 		} else if (strncmp(opts[i], "start=", 6) == 0) {
2969 			/* XXX - also compare length against bits */
2970 			if (BN_hex2bn(&start, opts[i]+6) == 0)
2971 				fatal("Invalid start point.");
2972 		} else if (strncmp(opts[i], "bits=", 5) == 0) {
2973 			moduli_bits = (int)strtonum(opts[i]+5, 1,
2974 			    INT_MAX, &errstr);
2975 			if (errstr) {
2976 				fatal("Invalid number: %s (%s)",
2977 					opts[i]+12, errstr);
2978 			}
2979 		} else {
2980 			fatal("Option \"%s\" is unsupported for moduli "
2981 			    "generation", opts[i]);
2982 		}
2983 	}
2984 
2985 	if ((out = fopen(out_file, "w")) == NULL) {
2986 		fatal("Couldn't open modulus candidate file \"%s\": %s",
2987 		    out_file, strerror(errno));
2988 	}
2989 	setvbuf(out, NULL, _IOLBF, 0);
2990 
2991 	if (moduli_bits == 0)
2992 		moduli_bits = DEFAULT_BITS;
2993 	if (gen_candidates(out, memory, moduli_bits, start) != 0)
2994 		fatal("modulus candidate generation failed");
2995 #else /* WITH_OPENSSL */
2996 	fatal("Moduli generation is not supported");
2997 #endif /* WITH_OPENSSL */
2998 }
2999 
3000 static void
3001 do_moduli_screen(const char *out_file, char **opts, size_t nopts)
3002 {
3003 #ifdef WITH_OPENSSL
3004 	/* Moduli generation/screening */
3005 	char *checkpoint = NULL;
3006 	u_int32_t generator_wanted = 0;
3007 	unsigned long start_lineno = 0, lines_to_process = 0;
3008 	int prime_tests = 0;
3009 	FILE *out, *in = stdin;
3010 	size_t i;
3011 	const char *errstr;
3012 
3013 	/* Parse options */
3014 	for (i = 0; i < nopts; i++) {
3015 		if (strncmp(opts[i], "lines=", 6) == 0) {
3016 			lines_to_process = strtoul(opts[i]+6, NULL, 10);
3017 		} else if (strncmp(opts[i], "start-line=", 11) == 0) {
3018 			start_lineno = strtoul(opts[i]+11, NULL, 10);
3019 		} else if (strncmp(opts[i], "checkpoint=", 11) == 0) {
3020 			free(checkpoint);
3021 			checkpoint = xstrdup(opts[i]+11);
3022 		} else if (strncmp(opts[i], "generator=", 10) == 0) {
3023 			generator_wanted = (u_int32_t)strtonum(
3024 			    opts[i]+10, 1, UINT_MAX, &errstr);
3025 			if (errstr != NULL) {
3026 				fatal("Generator invalid: %s (%s)",
3027 				    opts[i]+10, errstr);
3028 			}
3029 		} else if (strncmp(opts[i], "prime-tests=", 12) == 0) {
3030 			prime_tests = (int)strtonum(opts[i]+12, 1,
3031 			    INT_MAX, &errstr);
3032 			if (errstr) {
3033 				fatal("Invalid number: %s (%s)",
3034 					opts[i]+12, errstr);
3035 			}
3036 		} else {
3037 			fatal("Option \"%s\" is unsupported for moduli "
3038 			    "screening", opts[i]);
3039 		}
3040 	}
3041 
3042 	if (have_identity && strcmp(identity_file, "-") != 0) {
3043 		if ((in = fopen(identity_file, "r")) == NULL) {
3044 			fatal("Couldn't open modulus candidate "
3045 			    "file \"%s\": %s", identity_file,
3046 			    strerror(errno));
3047 		}
3048 	}
3049 
3050 	if ((out = fopen(out_file, "a")) == NULL) {
3051 		fatal("Couldn't open moduli file \"%s\": %s",
3052 		    out_file, strerror(errno));
3053 	}
3054 	setvbuf(out, NULL, _IOLBF, 0);
3055 	if (prime_test(in, out, prime_tests == 0 ? 100 : prime_tests,
3056 	    generator_wanted, checkpoint,
3057 	    start_lineno, lines_to_process) != 0)
3058 		fatal("modulus screening failed");
3059 	if (in != stdin)
3060 		(void)fclose(in);
3061 	free(checkpoint);
3062 #else /* WITH_OPENSSL */
3063 	fatal("Moduli screening is not supported");
3064 #endif /* WITH_OPENSSL */
3065 }
3066 
3067 /* Read and confirm a passphrase */
3068 static char *
3069 read_check_passphrase(const char *prompt1, const char *prompt2,
3070     const char *retry_prompt)
3071 {
3072 	char *passphrase1, *passphrase2;
3073 
3074 	for (;;) {
3075 		passphrase1 = read_passphrase(prompt1, RP_ALLOW_STDIN);
3076 		passphrase2 = read_passphrase(prompt2, RP_ALLOW_STDIN);
3077 		if (strcmp(passphrase1, passphrase2) == 0) {
3078 			freezero(passphrase2, strlen(passphrase2));
3079 			return passphrase1;
3080 		}
3081 		/* The passphrases do not match. Clear them and retry. */
3082 		freezero(passphrase1, strlen(passphrase1));
3083 		freezero(passphrase2, strlen(passphrase2));
3084 		fputs(retry_prompt, stdout);
3085 		fputc('\n', stdout);
3086 		fflush(stdout);
3087 	}
3088 	/* NOTREACHED */
3089 	return NULL;
3090 }
3091 
3092 static char *
3093 private_key_passphrase(void)
3094 {
3095 	if (identity_passphrase)
3096 		return xstrdup(identity_passphrase);
3097 	if (identity_new_passphrase)
3098 		return xstrdup(identity_new_passphrase);
3099 
3100 	return read_check_passphrase(
3101 	    "Enter passphrase (empty for no passphrase): ",
3102 	    "Enter same passphrase again: ",
3103 	    "Passphrases do not match.  Try again.");
3104 }
3105 
3106 static char *
3107 sk_suffix(const char *application, const uint8_t *user, size_t userlen)
3108 {
3109 	char *ret, *cp;
3110 	size_t slen, i;
3111 
3112 	/* Trim off URL-like preamble */
3113 	if (strncmp(application, "ssh://", 6) == 0)
3114 		ret =  xstrdup(application + 6);
3115 	else if (strncmp(application, "ssh:", 4) == 0)
3116 		ret =  xstrdup(application + 4);
3117 	else
3118 		ret = xstrdup(application);
3119 
3120 	/* Count trailing zeros in user */
3121 	for (i = 0; i < userlen; i++) {
3122 		if (user[userlen - i - 1] != 0)
3123 			break;
3124 	}
3125 	if (i >= userlen)
3126 		return ret; /* user-id was default all-zeros */
3127 
3128 	/* Append user-id, escaping non-UTF-8 characters */
3129 	slen = userlen - i;
3130 	if (asmprintf(&cp, INT_MAX, NULL, "%.*s", (int)slen, user) == -1)
3131 		fatal_f("asmprintf failed");
3132 	/* Don't emit a user-id that contains path or control characters */
3133 	if (strchr(cp, '/') != NULL || strstr(cp, "..") != NULL ||
3134 	    strchr(cp, '\\') != NULL) {
3135 		free(cp);
3136 		cp = tohex(user, slen);
3137 	}
3138 	xextendf(&ret, "_", "%s", cp);
3139 	free(cp);
3140 	return ret;
3141 }
3142 
3143 static int
3144 do_download_sk(const char *skprovider, const char *device)
3145 {
3146 	struct sshsk_resident_key **srks;
3147 	size_t nsrks, i;
3148 	int r, ret = -1;
3149 	char *fp, *pin = NULL, *pass = NULL, *path, *pubpath;
3150 	const char *ext;
3151 	struct sshkey *key;
3152 
3153 	if (skprovider == NULL)
3154 		fatal("Cannot download keys without provider");
3155 
3156 	pin = read_passphrase("Enter PIN for authenticator: ", RP_ALLOW_STDIN);
3157 	if (!quiet) {
3158 		printf("You may need to touch your authenticator "
3159 		    "to authorize key download.\n");
3160 	}
3161 	if ((r = sshsk_load_resident(skprovider, device, pin, 0,
3162 	    &srks, &nsrks)) != 0) {
3163 		if (pin != NULL)
3164 			freezero(pin, strlen(pin));
3165 		error_r(r, "Unable to load resident keys");
3166 		return -1;
3167 	}
3168 	if (nsrks == 0)
3169 		logit("No keys to download");
3170 	if (pin != NULL)
3171 		freezero(pin, strlen(pin));
3172 
3173 	for (i = 0; i < nsrks; i++) {
3174 		key = srks[i]->key;
3175 		if (key->type != KEY_ECDSA_SK && key->type != KEY_ED25519_SK) {
3176 			error("Unsupported key type %s (%d)",
3177 			    sshkey_type(key), key->type);
3178 			continue;
3179 		}
3180 		if ((fp = sshkey_fingerprint(key, fingerprint_hash,
3181 		    SSH_FP_DEFAULT)) == NULL)
3182 			fatal_f("sshkey_fingerprint failed");
3183 		debug_f("key %zu: %s %s %s (flags 0x%02x)", i,
3184 		    sshkey_type(key), fp, key->sk_application, key->sk_flags);
3185 		ext = sk_suffix(key->sk_application,
3186 		    srks[i]->user_id, srks[i]->user_id_len);
3187 		xasprintf(&path, "id_%s_rk%s%s",
3188 		    key->type == KEY_ECDSA_SK ? "ecdsa_sk" : "ed25519_sk",
3189 		    *ext == '\0' ? "" : "_", ext);
3190 
3191 		/* If the file already exists, ask the user to confirm. */
3192 		if (!confirm_overwrite(path)) {
3193 			free(path);
3194 			break;
3195 		}
3196 
3197 		/* Save the key with the application string as the comment */
3198 		if (pass == NULL)
3199 			pass = private_key_passphrase();
3200 		if ((r = sshkey_save_private(key, path, pass,
3201 		    key->sk_application, private_key_format,
3202 		    openssh_format_cipher, rounds)) != 0) {
3203 			error_r(r, "Saving key \"%s\" failed", path);
3204 			free(path);
3205 			break;
3206 		}
3207 		if (!quiet) {
3208 			printf("Saved %s key%s%s to %s\n", sshkey_type(key),
3209 			    *ext != '\0' ? " " : "",
3210 			    *ext != '\0' ? key->sk_application : "",
3211 			    path);
3212 		}
3213 
3214 		/* Save public key too */
3215 		xasprintf(&pubpath, "%s.pub", path);
3216 		free(path);
3217 		if ((r = sshkey_save_public(key, pubpath,
3218 		    key->sk_application)) != 0) {
3219 			error_r(r, "Saving public key \"%s\" failed", pubpath);
3220 			free(pubpath);
3221 			break;
3222 		}
3223 		free(pubpath);
3224 	}
3225 
3226 	if (i >= nsrks)
3227 		ret = 0; /* success */
3228 	if (pass != NULL)
3229 		freezero(pass, strlen(pass));
3230 	sshsk_free_resident_keys(srks, nsrks);
3231 	return ret;
3232 }
3233 
3234 static void
3235 save_attestation(struct sshbuf *attest, const char *path)
3236 {
3237 	mode_t omask;
3238 	int r;
3239 
3240 	if (path == NULL)
3241 		return; /* nothing to do */
3242 	if (attest == NULL || sshbuf_len(attest) == 0)
3243 		fatal("Enrollment did not return attestation data");
3244 	omask = umask(077);
3245 	r = sshbuf_write_file(path, attest);
3246 	umask(omask);
3247 	if (r != 0)
3248 		fatal_r(r, "Unable to write attestation data \"%s\"", path);
3249 	if (!quiet)
3250 		printf("Your FIDO attestation certificate has been saved in "
3251 		    "%s\n", path);
3252 }
3253 
3254 static int
3255 confirm_sk_overwrite(const char *application, const char *user)
3256 {
3257 	char yesno[3];
3258 
3259 	printf("A resident key scoped to '%s' with user id '%s' already "
3260 	    "exists.\n", application == NULL ? "ssh:" : application,
3261 	    user == NULL ? "null" : user);
3262 	printf("Overwrite key in token (y/n)? ");
3263 	fflush(stdout);
3264 	if (fgets(yesno, sizeof(yesno), stdin) == NULL)
3265 		return 0;
3266 	if (yesno[0] != 'y' && yesno[0] != 'Y')
3267 		return 0;
3268 	return 1;
3269 }
3270 
3271 static void
3272 usage(void)
3273 {
3274 	fprintf(stderr,
3275 	    "usage: ssh-keygen [-q] [-a rounds] [-b bits] [-C comment] [-f output_keyfile]\n"
3276 	    "                  [-m format] [-N new_passphrase] [-O option]\n"
3277 	    "                  [-t dsa | ecdsa | ecdsa-sk | ed25519 | ed25519-sk | rsa]\n"
3278 	    "                  [-w provider] [-Z cipher]\n"
3279 	    "       ssh-keygen -p [-a rounds] [-f keyfile] [-m format] [-N new_passphrase]\n"
3280 	    "                   [-P old_passphrase] [-Z cipher]\n"
3281 #ifdef WITH_OPENSSL
3282 	    "       ssh-keygen -i [-f input_keyfile] [-m key_format]\n"
3283 	    "       ssh-keygen -e [-f input_keyfile] [-m key_format]\n"
3284 #endif
3285 	    "       ssh-keygen -y [-f input_keyfile]\n"
3286 	    "       ssh-keygen -c [-a rounds] [-C comment] [-f keyfile] [-P passphrase]\n"
3287 	    "       ssh-keygen -l [-v] [-E fingerprint_hash] [-f input_keyfile]\n"
3288 	    "       ssh-keygen -B [-f input_keyfile]\n");
3289 #ifdef ENABLE_PKCS11
3290 	fprintf(stderr,
3291 	    "       ssh-keygen -D pkcs11\n");
3292 #endif
3293 	fprintf(stderr,
3294 	    "       ssh-keygen -F hostname [-lv] [-f known_hosts_file]\n"
3295 	    "       ssh-keygen -H [-f known_hosts_file]\n"
3296 	    "       ssh-keygen -K [-a rounds] [-w provider]\n"
3297 	    "       ssh-keygen -R hostname [-f known_hosts_file]\n"
3298 	    "       ssh-keygen -r hostname [-g] [-f input_keyfile]\n"
3299 #ifdef WITH_OPENSSL
3300 	    "       ssh-keygen -M generate [-O option] output_file\n"
3301 	    "       ssh-keygen -M screen [-f input_file] [-O option] output_file\n"
3302 #endif
3303 	    "       ssh-keygen -I certificate_identity -s ca_key [-hU] [-D pkcs11_provider]\n"
3304 	    "                  [-n principals] [-O option] [-V validity_interval]\n"
3305 	    "                  [-z serial_number] file ...\n"
3306 	    "       ssh-keygen -L [-f input_keyfile]\n"
3307 	    "       ssh-keygen -A [-a rounds] [-f prefix_path]\n"
3308 	    "       ssh-keygen -k -f krl_file [-u] [-s ca_public] [-z version_number]\n"
3309 	    "                  file ...\n"
3310 	    "       ssh-keygen -Q [-l] -f krl_file [file ...]\n"
3311 	    "       ssh-keygen -Y find-principals -s signature_file -f allowed_signers_file\n"
3312 	    "       ssh-keygen -Y match-principals -I signer_identity -f allowed_signers_file\n"
3313 	    "       ssh-keygen -Y check-novalidate -n namespace -s signature_file\n"
3314 	    "       ssh-keygen -Y sign -f key_file -n namespace file [-O option] ...\n"
3315 	    "       ssh-keygen -Y verify -f allowed_signers_file -I signer_identity\n"
3316 	    "                  -n namespace -s signature_file [-r krl_file] [-O option]\n");
3317 	exit(1);
3318 }
3319 
3320 /*
3321  * Main program for key management.
3322  */
3323 int
3324 main(int argc, char **argv)
3325 {
3326 	char comment[1024], *passphrase = NULL;
3327 	char *rr_hostname = NULL, *ep, *fp, *ra;
3328 	struct sshkey *private, *public;
3329 	struct passwd *pw;
3330 	int r, opt, type;
3331 	int change_passphrase = 0, change_comment = 0, show_cert = 0;
3332 	int find_host = 0, delete_host = 0, hash_hosts = 0;
3333 	int gen_all_hostkeys = 0, gen_krl = 0, update_krl = 0, check_krl = 0;
3334 	int prefer_agent = 0, convert_to = 0, convert_from = 0;
3335 	int print_public = 0, print_generic = 0, cert_serial_autoinc = 0;
3336 	int do_gen_candidates = 0, do_screen_candidates = 0, download_sk = 0;
3337 	unsigned long long cert_serial = 0;
3338 	char *identity_comment = NULL, *ca_key_path = NULL, **opts = NULL;
3339 	char *sk_application = NULL, *sk_device = NULL, *sk_user = NULL;
3340 	char *sk_attestation_path = NULL;
3341 	struct sshbuf *challenge = NULL, *attest = NULL;
3342 	size_t i, nopts = 0;
3343 	u_int32_t bits = 0;
3344 	uint8_t sk_flags = SSH_SK_USER_PRESENCE_REQD;
3345 	const char *errstr;
3346 	int log_level = SYSLOG_LEVEL_INFO;
3347 	char *sign_op = NULL;
3348 
3349 	extern int optind;
3350 	extern char *optarg;
3351 
3352 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
3353 	sanitise_stdfd();
3354 
3355 	__progname = ssh_get_progname(argv[0]);
3356 
3357 	seed_rng();
3358 
3359 	log_init(argv[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
3360 
3361 	msetlocale();
3362 
3363 	/* we need this for the home * directory.  */
3364 	pw = getpwuid(getuid());
3365 	if (!pw)
3366 		fatal("No user exists for uid %lu", (u_long)getuid());
3367 	pw = pwcopy(pw);
3368 	if (gethostname(hostname, sizeof(hostname)) == -1)
3369 		fatal("gethostname: %s", strerror(errno));
3370 
3371 	sk_provider = getenv("SSH_SK_PROVIDER");
3372 
3373 	/* Remaining characters: dGjJSTWx */
3374 	while ((opt = getopt(argc, argv, "ABHKLQUXceghiklopquvy"
3375 	    "C:D:E:F:I:M:N:O:P:R:V:Y:Z:"
3376 	    "a:b:f:g:m:n:r:s:t:w:z:")) != -1) {
3377 		switch (opt) {
3378 		case 'A':
3379 			gen_all_hostkeys = 1;
3380 			break;
3381 		case 'b':
3382 			bits = (u_int32_t)strtonum(optarg, 1, UINT32_MAX,
3383 			    &errstr);
3384 			if (errstr)
3385 				fatal("Bits has bad value %s (%s)",
3386 					optarg, errstr);
3387 			break;
3388 		case 'E':
3389 			fingerprint_hash = ssh_digest_alg_by_name(optarg);
3390 			if (fingerprint_hash == -1)
3391 				fatal("Invalid hash algorithm \"%s\"", optarg);
3392 			break;
3393 		case 'F':
3394 			find_host = 1;
3395 			rr_hostname = optarg;
3396 			break;
3397 		case 'H':
3398 			hash_hosts = 1;
3399 			break;
3400 		case 'I':
3401 			cert_key_id = optarg;
3402 			break;
3403 		case 'R':
3404 			delete_host = 1;
3405 			rr_hostname = optarg;
3406 			break;
3407 		case 'L':
3408 			show_cert = 1;
3409 			break;
3410 		case 'l':
3411 			print_fingerprint = 1;
3412 			break;
3413 		case 'B':
3414 			print_bubblebabble = 1;
3415 			break;
3416 		case 'm':
3417 			if (strcasecmp(optarg, "RFC4716") == 0 ||
3418 			    strcasecmp(optarg, "ssh2") == 0) {
3419 				convert_format = FMT_RFC4716;
3420 				break;
3421 			}
3422 			if (strcasecmp(optarg, "PKCS8") == 0) {
3423 				convert_format = FMT_PKCS8;
3424 				private_key_format = SSHKEY_PRIVATE_PKCS8;
3425 				break;
3426 			}
3427 			if (strcasecmp(optarg, "PEM") == 0) {
3428 				convert_format = FMT_PEM;
3429 				private_key_format = SSHKEY_PRIVATE_PEM;
3430 				break;
3431 			}
3432 			fatal("Unsupported conversion format \"%s\"", optarg);
3433 		case 'n':
3434 			cert_principals = optarg;
3435 			break;
3436 		case 'o':
3437 			/* no-op; new format is already the default */
3438 			break;
3439 		case 'p':
3440 			change_passphrase = 1;
3441 			break;
3442 		case 'c':
3443 			change_comment = 1;
3444 			break;
3445 		case 'f':
3446 			if (strlcpy(identity_file, optarg,
3447 			    sizeof(identity_file)) >= sizeof(identity_file))
3448 				fatal("Identity filename too long");
3449 			have_identity = 1;
3450 			break;
3451 		case 'g':
3452 			print_generic = 1;
3453 			break;
3454 		case 'K':
3455 			download_sk = 1;
3456 			break;
3457 		case 'P':
3458 			identity_passphrase = optarg;
3459 			break;
3460 		case 'N':
3461 			identity_new_passphrase = optarg;
3462 			break;
3463 		case 'Q':
3464 			check_krl = 1;
3465 			break;
3466 		case 'O':
3467 			opts = xrecallocarray(opts, nopts, nopts + 1,
3468 			    sizeof(*opts));
3469 			opts[nopts++] = xstrdup(optarg);
3470 			break;
3471 		case 'Z':
3472 			openssh_format_cipher = optarg;
3473 			if (cipher_by_name(openssh_format_cipher) == NULL)
3474 				fatal("Invalid OpenSSH-format cipher '%s'",
3475 				    openssh_format_cipher);
3476 			break;
3477 		case 'C':
3478 			identity_comment = optarg;
3479 			break;
3480 		case 'q':
3481 			quiet = 1;
3482 			break;
3483 		case 'e':
3484 			/* export key */
3485 			convert_to = 1;
3486 			break;
3487 		case 'h':
3488 			cert_key_type = SSH2_CERT_TYPE_HOST;
3489 			certflags_flags = 0;
3490 			break;
3491 		case 'k':
3492 			gen_krl = 1;
3493 			break;
3494 		case 'i':
3495 		case 'X':
3496 			/* import key */
3497 			convert_from = 1;
3498 			break;
3499 		case 'y':
3500 			print_public = 1;
3501 			break;
3502 		case 's':
3503 			ca_key_path = optarg;
3504 			break;
3505 		case 't':
3506 			key_type_name = optarg;
3507 			break;
3508 		case 'D':
3509 			pkcs11provider = optarg;
3510 			break;
3511 		case 'U':
3512 			prefer_agent = 1;
3513 			break;
3514 		case 'u':
3515 			update_krl = 1;
3516 			break;
3517 		case 'v':
3518 			if (log_level == SYSLOG_LEVEL_INFO)
3519 				log_level = SYSLOG_LEVEL_DEBUG1;
3520 			else {
3521 				if (log_level >= SYSLOG_LEVEL_DEBUG1 &&
3522 				    log_level < SYSLOG_LEVEL_DEBUG3)
3523 					log_level++;
3524 			}
3525 			break;
3526 		case 'r':
3527 			rr_hostname = optarg;
3528 			break;
3529 		case 'a':
3530 			rounds = (int)strtonum(optarg, 1, INT_MAX, &errstr);
3531 			if (errstr)
3532 				fatal("Invalid number: %s (%s)",
3533 					optarg, errstr);
3534 			break;
3535 		case 'V':
3536 			parse_cert_times(optarg);
3537 			break;
3538 		case 'Y':
3539 			sign_op = optarg;
3540 			break;
3541 		case 'w':
3542 			sk_provider = optarg;
3543 			break;
3544 		case 'z':
3545 			errno = 0;
3546 			if (*optarg == '+') {
3547 				cert_serial_autoinc = 1;
3548 				optarg++;
3549 			}
3550 			cert_serial = strtoull(optarg, &ep, 10);
3551 			if (*optarg < '0' || *optarg > '9' || *ep != '\0' ||
3552 			    (errno == ERANGE && cert_serial == ULLONG_MAX))
3553 				fatal("Invalid serial number \"%s\"", optarg);
3554 			break;
3555 		case 'M':
3556 			if (strcmp(optarg, "generate") == 0)
3557 				do_gen_candidates = 1;
3558 			else if (strcmp(optarg, "screen") == 0)
3559 				do_screen_candidates = 1;
3560 			else
3561 				fatal("Unsupported moduli option %s", optarg);
3562 			break;
3563 		default:
3564 			usage();
3565 		}
3566 	}
3567 
3568 #ifdef ENABLE_SK_INTERNAL
3569 	if (sk_provider == NULL)
3570 		sk_provider = "internal";
3571 #endif
3572 
3573 	/* reinit */
3574 	log_init(argv[0], log_level, SYSLOG_FACILITY_USER, 1);
3575 
3576 	argv += optind;
3577 	argc -= optind;
3578 
3579 	if (sign_op != NULL) {
3580 		if (strncmp(sign_op, "find-principals", 15) == 0) {
3581 			if (ca_key_path == NULL) {
3582 				error("Too few arguments for find-principals:"
3583 				    "missing signature file");
3584 				exit(1);
3585 			}
3586 			if (!have_identity) {
3587 				error("Too few arguments for find-principals:"
3588 				    "missing allowed keys file");
3589 				exit(1);
3590 			}
3591 			return sig_find_principals(ca_key_path, identity_file,
3592 			    opts, nopts);
3593 		} else if (strncmp(sign_op, "match-principals", 16) == 0) {
3594 			if (!have_identity) {
3595 				error("Too few arguments for match-principals:"
3596 				    "missing allowed keys file");
3597 				exit(1);
3598 			}
3599 			if (cert_key_id == NULL) {
3600 				error("Too few arguments for match-principals: "
3601 				    "missing principal ID");
3602 				exit(1);
3603 			}
3604 			return sig_match_principals(identity_file, cert_key_id,
3605 			    opts, nopts);
3606 		} else if (strncmp(sign_op, "sign", 4) == 0) {
3607 			/* NB. cert_principals is actually namespace, via -n */
3608 			if (cert_principals == NULL ||
3609 			    *cert_principals == '\0') {
3610 				error("Too few arguments for sign: "
3611 				    "missing namespace");
3612 				exit(1);
3613 			}
3614 			if (!have_identity) {
3615 				error("Too few arguments for sign: "
3616 				    "missing key");
3617 				exit(1);
3618 			}
3619 			return sig_sign(identity_file, cert_principals,
3620 			    prefer_agent, argc, argv, opts, nopts);
3621 		} else if (strncmp(sign_op, "check-novalidate", 16) == 0) {
3622 			/* NB. cert_principals is actually namespace, via -n */
3623 			if (cert_principals == NULL ||
3624 			    *cert_principals == '\0') {
3625 				error("Too few arguments for check-novalidate: "
3626 				    "missing namespace");
3627 				exit(1);
3628 			}
3629 			if (ca_key_path == NULL) {
3630 				error("Too few arguments for check-novalidate: "
3631 				    "missing signature file");
3632 				exit(1);
3633 			}
3634 			return sig_verify(ca_key_path, cert_principals,
3635 			    NULL, NULL, NULL, opts, nopts);
3636 		} else if (strncmp(sign_op, "verify", 6) == 0) {
3637 			/* NB. cert_principals is actually namespace, via -n */
3638 			if (cert_principals == NULL ||
3639 			    *cert_principals == '\0') {
3640 				error("Too few arguments for verify: "
3641 				    "missing namespace");
3642 				exit(1);
3643 			}
3644 			if (ca_key_path == NULL) {
3645 				error("Too few arguments for verify: "
3646 				    "missing signature file");
3647 				exit(1);
3648 			}
3649 			if (!have_identity) {
3650 				error("Too few arguments for sign: "
3651 				    "missing allowed keys file");
3652 				exit(1);
3653 			}
3654 			if (cert_key_id == NULL) {
3655 				error("Too few arguments for verify: "
3656 				    "missing principal identity");
3657 				exit(1);
3658 			}
3659 			return sig_verify(ca_key_path, cert_principals,
3660 			    cert_key_id, identity_file, rr_hostname,
3661 			    opts, nopts);
3662 		}
3663 		error("Unsupported operation for -Y: \"%s\"", sign_op);
3664 		usage();
3665 		/* NOTREACHED */
3666 	}
3667 
3668 	if (ca_key_path != NULL) {
3669 		if (argc < 1 && !gen_krl) {
3670 			error("Too few arguments.");
3671 			usage();
3672 		}
3673 	} else if (argc > 0 && !gen_krl && !check_krl &&
3674 	    !do_gen_candidates && !do_screen_candidates) {
3675 		error("Too many arguments.");
3676 		usage();
3677 	}
3678 	if (change_passphrase && change_comment) {
3679 		error("Can only have one of -p and -c.");
3680 		usage();
3681 	}
3682 	if (print_fingerprint && (delete_host || hash_hosts)) {
3683 		error("Cannot use -l with -H or -R.");
3684 		usage();
3685 	}
3686 	if (gen_krl) {
3687 		do_gen_krl(pw, update_krl, ca_key_path,
3688 		    cert_serial, identity_comment, argc, argv);
3689 		return (0);
3690 	}
3691 	if (check_krl) {
3692 		do_check_krl(pw, print_fingerprint, argc, argv);
3693 		return (0);
3694 	}
3695 	if (ca_key_path != NULL) {
3696 		if (cert_key_id == NULL)
3697 			fatal("Must specify key id (-I) when certifying");
3698 		for (i = 0; i < nopts; i++)
3699 			add_cert_option(opts[i]);
3700 		do_ca_sign(pw, ca_key_path, prefer_agent,
3701 		    cert_serial, cert_serial_autoinc, argc, argv);
3702 	}
3703 	if (show_cert)
3704 		do_show_cert(pw);
3705 	if (delete_host || hash_hosts || find_host) {
3706 		do_known_hosts(pw, rr_hostname, find_host,
3707 		    delete_host, hash_hosts);
3708 	}
3709 	if (pkcs11provider != NULL)
3710 		do_download(pw);
3711 	if (download_sk) {
3712 		for (i = 0; i < nopts; i++) {
3713 			if (strncasecmp(opts[i], "device=", 7) == 0) {
3714 				sk_device = xstrdup(opts[i] + 7);
3715 			} else {
3716 				fatal("Option \"%s\" is unsupported for "
3717 				    "FIDO authenticator download", opts[i]);
3718 			}
3719 		}
3720 		return do_download_sk(sk_provider, sk_device);
3721 	}
3722 	if (print_fingerprint || print_bubblebabble)
3723 		do_fingerprint(pw);
3724 	if (change_passphrase)
3725 		do_change_passphrase(pw);
3726 	if (change_comment)
3727 		do_change_comment(pw, identity_comment);
3728 #ifdef WITH_OPENSSL
3729 	if (convert_to)
3730 		do_convert_to(pw);
3731 	if (convert_from)
3732 		do_convert_from(pw);
3733 #else /* WITH_OPENSSL */
3734 	if (convert_to || convert_from)
3735 		fatal("key conversion disabled at compile time");
3736 #endif /* WITH_OPENSSL */
3737 	if (print_public)
3738 		do_print_public(pw);
3739 	if (rr_hostname != NULL) {
3740 		unsigned int n = 0;
3741 
3742 		if (have_identity) {
3743 			n = do_print_resource_record(pw, identity_file,
3744 			    rr_hostname, print_generic, opts, nopts);
3745 			if (n == 0)
3746 				fatal("%s: %s", identity_file, strerror(errno));
3747 			exit(0);
3748 		} else {
3749 
3750 			n += do_print_resource_record(pw,
3751 			    _PATH_HOST_RSA_KEY_FILE, rr_hostname,
3752 			    print_generic, opts, nopts);
3753 			n += do_print_resource_record(pw,
3754 			    _PATH_HOST_DSA_KEY_FILE, rr_hostname,
3755 			    print_generic, opts, nopts);
3756 			n += do_print_resource_record(pw,
3757 			    _PATH_HOST_ECDSA_KEY_FILE, rr_hostname,
3758 			    print_generic, opts, nopts);
3759 			n += do_print_resource_record(pw,
3760 			    _PATH_HOST_ED25519_KEY_FILE, rr_hostname,
3761 			    print_generic, opts, nopts);
3762 			n += do_print_resource_record(pw,
3763 			    _PATH_HOST_XMSS_KEY_FILE, rr_hostname,
3764 			    print_generic, opts, nopts);
3765 			if (n == 0)
3766 				fatal("no keys found.");
3767 			exit(0);
3768 		}
3769 	}
3770 
3771 	if (do_gen_candidates || do_screen_candidates) {
3772 		if (argc <= 0)
3773 			fatal("No output file specified");
3774 		else if (argc > 1)
3775 			fatal("Too many output files specified");
3776 	}
3777 	if (do_gen_candidates) {
3778 		do_moduli_gen(argv[0], opts, nopts);
3779 		return 0;
3780 	}
3781 	if (do_screen_candidates) {
3782 		do_moduli_screen(argv[0], opts, nopts);
3783 		return 0;
3784 	}
3785 
3786 	if (gen_all_hostkeys) {
3787 		do_gen_all_hostkeys(pw);
3788 		return (0);
3789 	}
3790 
3791 	if (key_type_name == NULL)
3792 		key_type_name = DEFAULT_KEY_TYPE_NAME;
3793 
3794 	type = sshkey_type_from_name(key_type_name);
3795 	type_bits_valid(type, key_type_name, &bits);
3796 
3797 	if (!quiet)
3798 		printf("Generating public/private %s key pair.\n",
3799 		    key_type_name);
3800 	switch (type) {
3801 	case KEY_ECDSA_SK:
3802 	case KEY_ED25519_SK:
3803 		for (i = 0; i < nopts; i++) {
3804 			if (strcasecmp(opts[i], "no-touch-required") == 0) {
3805 				sk_flags &= ~SSH_SK_USER_PRESENCE_REQD;
3806 			} else if (strcasecmp(opts[i], "verify-required") == 0) {
3807 				sk_flags |= SSH_SK_USER_VERIFICATION_REQD;
3808 			} else if (strcasecmp(opts[i], "resident") == 0) {
3809 				sk_flags |= SSH_SK_RESIDENT_KEY;
3810 			} else if (strncasecmp(opts[i], "device=", 7) == 0) {
3811 				sk_device = xstrdup(opts[i] + 7);
3812 			} else if (strncasecmp(opts[i], "user=", 5) == 0) {
3813 				sk_user = xstrdup(opts[i] + 5);
3814 			} else if (strncasecmp(opts[i], "challenge=", 10) == 0) {
3815 				if ((r = sshbuf_load_file(opts[i] + 10,
3816 				    &challenge)) != 0) {
3817 					fatal_r(r, "Unable to load FIDO "
3818 					    "enrollment challenge \"%s\"",
3819 					    opts[i] + 10);
3820 				}
3821 			} else if (strncasecmp(opts[i],
3822 			    "write-attestation=", 18) == 0) {
3823 				sk_attestation_path = opts[i] + 18;
3824 			} else if (strncasecmp(opts[i],
3825 			    "application=", 12) == 0) {
3826 				sk_application = xstrdup(opts[i] + 12);
3827 				if (strncmp(sk_application, "ssh:", 4) != 0) {
3828 					fatal("FIDO application string must "
3829 					    "begin with \"ssh:\"");
3830 				}
3831 			} else {
3832 				fatal("Option \"%s\" is unsupported for "
3833 				    "FIDO authenticator enrollment", opts[i]);
3834 			}
3835 		}
3836 		if ((attest = sshbuf_new()) == NULL)
3837 			fatal("sshbuf_new failed");
3838 		r = 0;
3839 		for (i = 0 ;;) {
3840 			if (!quiet) {
3841 				printf("You may need to touch your "
3842 				    "authenticator%s to authorize key "
3843 				    "generation.\n",
3844 				    r == 0 ? "" : " again");
3845 			}
3846 			fflush(stdout);
3847 			r = sshsk_enroll(type, sk_provider, sk_device,
3848 			    sk_application == NULL ? "ssh:" : sk_application,
3849 			    sk_user, sk_flags, passphrase, challenge,
3850 			    &private, attest);
3851 			if (r == 0)
3852 				break;
3853 			if (r == SSH_ERR_KEY_BAD_PERMISSIONS &&
3854 			    (sk_flags & SSH_SK_RESIDENT_KEY) != 0 &&
3855 			    (sk_flags & SSH_SK_FORCE_OPERATION) == 0 &&
3856 			    confirm_sk_overwrite(sk_application, sk_user)) {
3857 				sk_flags |= SSH_SK_FORCE_OPERATION;
3858 				continue;
3859 			}
3860 			if (r != SSH_ERR_KEY_WRONG_PASSPHRASE)
3861 				fatal_r(r, "Key enrollment failed");
3862 			else if (passphrase != NULL) {
3863 				error("PIN incorrect");
3864 				freezero(passphrase, strlen(passphrase));
3865 				passphrase = NULL;
3866 			}
3867 			if (++i >= 3)
3868 				fatal("Too many incorrect PINs");
3869 			passphrase = read_passphrase("Enter PIN for "
3870 			    "authenticator: ", RP_ALLOW_STDIN);
3871 		}
3872 		if (passphrase != NULL) {
3873 			freezero(passphrase, strlen(passphrase));
3874 			passphrase = NULL;
3875 		}
3876 		break;
3877 	default:
3878 		if ((r = sshkey_generate(type, bits, &private)) != 0)
3879 			fatal("sshkey_generate failed");
3880 		break;
3881 	}
3882 	if ((r = sshkey_from_private(private, &public)) != 0)
3883 		fatal_r(r, "sshkey_from_private");
3884 
3885 	if (!have_identity)
3886 		ask_filename(pw, "Enter file in which to save the key");
3887 
3888 	/* Create ~/.ssh directory if it doesn't already exist. */
3889 	hostfile_create_user_ssh_dir(identity_file, !quiet);
3890 
3891 	/* If the file already exists, ask the user to confirm. */
3892 	if (!confirm_overwrite(identity_file))
3893 		exit(1);
3894 
3895 	/* Determine the passphrase for the private key */
3896 	passphrase = private_key_passphrase();
3897 	if (identity_comment) {
3898 		strlcpy(comment, identity_comment, sizeof(comment));
3899 	} else {
3900 		/* Create default comment field for the passphrase. */
3901 		snprintf(comment, sizeof comment, "%s@%s", pw->pw_name, hostname);
3902 	}
3903 
3904 	/* Save the key with the given passphrase and comment. */
3905 	if ((r = sshkey_save_private(private, identity_file, passphrase,
3906 	    comment, private_key_format, openssh_format_cipher, rounds)) != 0) {
3907 		error_r(r, "Saving key \"%s\" failed", identity_file);
3908 		freezero(passphrase, strlen(passphrase));
3909 		exit(1);
3910 	}
3911 	freezero(passphrase, strlen(passphrase));
3912 	sshkey_free(private);
3913 
3914 	if (!quiet) {
3915 		printf("Your identification has been saved in %s\n",
3916 		    identity_file);
3917 	}
3918 
3919 	strlcat(identity_file, ".pub", sizeof(identity_file));
3920 	if ((r = sshkey_save_public(public, identity_file, comment)) != 0)
3921 		fatal_r(r, "Unable to save public key to %s", identity_file);
3922 
3923 	if (!quiet) {
3924 		fp = sshkey_fingerprint(public, fingerprint_hash,
3925 		    SSH_FP_DEFAULT);
3926 		ra = sshkey_fingerprint(public, fingerprint_hash,
3927 		    SSH_FP_RANDOMART);
3928 		if (fp == NULL || ra == NULL)
3929 			fatal("sshkey_fingerprint failed");
3930 		printf("Your public key has been saved in %s\n",
3931 		    identity_file);
3932 		printf("The key fingerprint is:\n");
3933 		printf("%s %s\n", fp, comment);
3934 		printf("The key's randomart image is:\n");
3935 		printf("%s\n", ra);
3936 		free(ra);
3937 		free(fp);
3938 	}
3939 
3940 	if (sk_attestation_path != NULL)
3941 		save_attestation(attest, sk_attestation_path);
3942 
3943 	sshbuf_free(attest);
3944 	sshkey_free(public);
3945 
3946 	exit(0);
3947 }
3948