xref: /openssh-portable/ssh-add.c (revision fe2ec0b9)
1 /* $OpenBSD: ssh-add.c,v 1.156 2020/06/26 05:04:07 djm Exp $ */
2 /*
3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5  *                    All rights reserved
6  * Adds an identity to the authentication server, or removes an identity.
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  * SSH2 implementation,
15  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include "includes.h"
39 
40 #include <sys/types.h>
41 #include <sys/stat.h>
42 
43 #ifdef WITH_OPENSSL
44 # include <openssl/evp.h>
45 # include "openbsd-compat/openssl-compat.h"
46 #endif
47 
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <pwd.h>
51 #include <stdarg.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <limits.h>
57 
58 #include "xmalloc.h"
59 #include "ssh.h"
60 #include "log.h"
61 #include "sshkey.h"
62 #include "sshbuf.h"
63 #include "authfd.h"
64 #include "authfile.h"
65 #include "pathnames.h"
66 #include "misc.h"
67 #include "ssherr.h"
68 #include "digest.h"
69 #include "ssh-sk.h"
70 
71 /* argv0 */
72 extern char *__progname;
73 
74 /* Default files to add */
75 static char *default_files[] = {
76 #ifdef WITH_OPENSSL
77 	_PATH_SSH_CLIENT_ID_RSA,
78 	_PATH_SSH_CLIENT_ID_DSA,
79 #ifdef OPENSSL_HAS_ECC
80 	_PATH_SSH_CLIENT_ID_ECDSA,
81 	_PATH_SSH_CLIENT_ID_ECDSA_SK,
82 #endif
83 #endif /* WITH_OPENSSL */
84 	_PATH_SSH_CLIENT_ID_ED25519,
85 	_PATH_SSH_CLIENT_ID_ED25519_SK,
86 	_PATH_SSH_CLIENT_ID_XMSS,
87 	NULL
88 };
89 
90 static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
91 
92 /* Default lifetime (0 == forever) */
93 static long lifetime = 0;
94 
95 /* User has to confirm key use */
96 static int confirm = 0;
97 
98 /* Maximum number of signatures (XMSS) */
99 static u_int maxsign = 0;
100 static u_int minleft = 0;
101 
102 /* we keep a cache of one passphrase */
103 static char *pass = NULL;
104 static void
105 clear_pass(void)
106 {
107 	if (pass) {
108 		freezero(pass, strlen(pass));
109 		pass = NULL;
110 	}
111 }
112 
113 static int
114 delete_one(int agent_fd, const struct sshkey *key, const char *comment,
115     const char *path, int qflag)
116 {
117 	int r;
118 
119 	if ((r = ssh_remove_identity(agent_fd, key)) != 0) {
120 		fprintf(stderr, "Could not remove identity \"%s\": %s\n",
121 		    path, ssh_err(r));
122 		return r;
123 	}
124 	if (!qflag) {
125 		fprintf(stderr, "Identity removed: %s %s (%s)\n", path,
126 		    sshkey_type(key), comment);
127 	}
128 	return 0;
129 }
130 
131 static int
132 delete_stdin(int agent_fd, int qflag)
133 {
134 	char *line = NULL, *cp;
135 	size_t linesize = 0;
136 	struct sshkey *key = NULL;
137 	int lnum = 0, r, ret = -1;
138 
139 	while (getline(&line, &linesize, stdin) != -1) {
140 		lnum++;
141 		sshkey_free(key);
142 		key = NULL;
143 		line[strcspn(line, "\n")] = '\0';
144 		cp = line + strspn(line, " \t");
145 		if (*cp == '#' || *cp == '\0')
146 			continue;
147 		if ((key = sshkey_new(KEY_UNSPEC)) == NULL)
148 			fatal("%s: sshkey_new", __func__);
149 		if ((r = sshkey_read(key, &cp)) != 0) {
150 			error("(stdin):%d: invalid key: %s", lnum, ssh_err(r));
151 			continue;
152 		}
153 		if (delete_one(agent_fd, key, cp, "(stdin)", qflag) == 0)
154 			ret = 0;
155 	}
156 	sshkey_free(key);
157 	free(line);
158 	return ret;
159 }
160 
161 static int
162 delete_file(int agent_fd, const char *filename, int key_only, int qflag)
163 {
164 	struct sshkey *public, *cert = NULL;
165 	char *certpath = NULL, *comment = NULL;
166 	int r, ret = -1;
167 
168 	if (strcmp(filename, "-") == 0)
169 		return delete_stdin(agent_fd, qflag);
170 
171 	if ((r = sshkey_load_public(filename, &public,  &comment)) != 0) {
172 		printf("Bad key file %s: %s\n", filename, ssh_err(r));
173 		return -1;
174 	}
175 	if (delete_one(agent_fd, public, comment, filename, qflag) == 0)
176 		ret = 0;
177 
178 	if (key_only)
179 		goto out;
180 
181 	/* Now try to delete the corresponding certificate too */
182 	free(comment);
183 	comment = NULL;
184 	xasprintf(&certpath, "%s-cert.pub", filename);
185 	if ((r = sshkey_load_public(certpath, &cert, &comment)) != 0) {
186 		if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
187 			error("Failed to load certificate \"%s\": %s",
188 			    certpath, ssh_err(r));
189 		goto out;
190 	}
191 
192 	if (!sshkey_equal_public(cert, public))
193 		fatal("Certificate %s does not match private key %s",
194 		    certpath, filename);
195 
196 	if (delete_one(agent_fd, cert, comment, certpath, qflag) == 0)
197 		ret = 0;
198 
199  out:
200 	sshkey_free(cert);
201 	sshkey_free(public);
202 	free(certpath);
203 	free(comment);
204 
205 	return ret;
206 }
207 
208 /* Send a request to remove all identities. */
209 static int
210 delete_all(int agent_fd, int qflag)
211 {
212 	int ret = -1;
213 
214 	/*
215 	 * Since the agent might be forwarded, old or non-OpenSSH, when asked
216 	 * to remove all keys, attempt to remove both protocol v.1 and v.2
217 	 * keys.
218 	 */
219 	if (ssh_remove_all_identities(agent_fd, 2) == 0)
220 		ret = 0;
221 	/* ignore error-code for ssh1 */
222 	ssh_remove_all_identities(agent_fd, 1);
223 
224 	if (ret != 0)
225 		fprintf(stderr, "Failed to remove all identities.\n");
226 	else if (!qflag)
227 		fprintf(stderr, "All identities removed.\n");
228 
229 	return ret;
230 }
231 
232 static int
233 add_file(int agent_fd, const char *filename, int key_only, int qflag,
234     const char *skprovider)
235 {
236 	struct sshkey *private, *cert;
237 	char *comment = NULL;
238 	char msg[1024], *certpath = NULL;
239 	int r, fd, ret = -1;
240 	size_t i;
241 	u_int32_t left;
242 	struct sshbuf *keyblob;
243 	struct ssh_identitylist *idlist;
244 
245 	if (strcmp(filename, "-") == 0) {
246 		fd = STDIN_FILENO;
247 		filename = "(stdin)";
248 	} else if ((fd = open(filename, O_RDONLY)) == -1) {
249 		perror(filename);
250 		return -1;
251 	}
252 
253 	/*
254 	 * Since we'll try to load a keyfile multiple times, permission errors
255 	 * will occur multiple times, so check perms first and bail if wrong.
256 	 */
257 	if (fd != STDIN_FILENO) {
258 		if (sshkey_perm_ok(fd, filename) != 0) {
259 			close(fd);
260 			return -1;
261 		}
262 	}
263 	if ((r = sshbuf_load_fd(fd, &keyblob)) != 0) {
264 		fprintf(stderr, "Error loading key \"%s\": %s\n",
265 		    filename, ssh_err(r));
266 		sshbuf_free(keyblob);
267 		close(fd);
268 		return -1;
269 	}
270 	close(fd);
271 
272 	/* At first, try empty passphrase */
273 	if ((r = sshkey_parse_private_fileblob(keyblob, "", &private,
274 	    &comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
275 		fprintf(stderr, "Error loading key \"%s\": %s\n",
276 		    filename, ssh_err(r));
277 		goto fail_load;
278 	}
279 	/* try last */
280 	if (private == NULL && pass != NULL) {
281 		if ((r = sshkey_parse_private_fileblob(keyblob, pass, &private,
282 		    &comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
283 			fprintf(stderr, "Error loading key \"%s\": %s\n",
284 			    filename, ssh_err(r));
285 			goto fail_load;
286 		}
287 	}
288 	if (private == NULL) {
289 		/* clear passphrase since it did not work */
290 		clear_pass();
291 		snprintf(msg, sizeof msg, "Enter passphrase for %s%s: ",
292 		    filename, confirm ? " (will confirm each use)" : "");
293 		for (;;) {
294 			pass = read_passphrase(msg, RP_ALLOW_STDIN);
295 			if (strcmp(pass, "") == 0)
296 				goto fail_load;
297 			if ((r = sshkey_parse_private_fileblob(keyblob, pass,
298 			    &private, &comment)) == 0)
299 				break;
300 			else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
301 				fprintf(stderr,
302 				    "Error loading key \"%s\": %s\n",
303 				    filename, ssh_err(r));
304  fail_load:
305 				clear_pass();
306 				sshbuf_free(keyblob);
307 				return -1;
308 			}
309 			clear_pass();
310 			snprintf(msg, sizeof msg,
311 			    "Bad passphrase, try again for %s%s: ", filename,
312 			    confirm ? " (will confirm each use)" : "");
313 		}
314 	}
315 	if (comment == NULL || *comment == '\0')
316 		comment = xstrdup(filename);
317 	sshbuf_free(keyblob);
318 
319 	/* For XMSS */
320 	if ((r = sshkey_set_filename(private, filename)) != 0) {
321 		fprintf(stderr, "Could not add filename to private key: %s (%s)\n",
322 		    filename, comment);
323 		goto out;
324 	}
325 	if (maxsign && minleft &&
326 	    (r = ssh_fetch_identitylist(agent_fd, &idlist)) == 0) {
327 		for (i = 0; i < idlist->nkeys; i++) {
328 			if (!sshkey_equal_public(idlist->keys[i], private))
329 				continue;
330 			left = sshkey_signatures_left(idlist->keys[i]);
331 			if (left < minleft) {
332 				fprintf(stderr,
333 				    "Only %d signatures left.\n", left);
334 				break;
335 			}
336 			fprintf(stderr, "Skipping update: ");
337 			if (left == minleft) {
338 				fprintf(stderr,
339 				   "required signatures left (%d).\n", left);
340 			} else {
341 				fprintf(stderr,
342 				   "more signatures left (%d) than"
343 				    " required (%d).\n", left, minleft);
344 			}
345 			ssh_free_identitylist(idlist);
346 			goto out;
347 		}
348 		ssh_free_identitylist(idlist);
349 	}
350 
351 	if (!sshkey_is_sk(private))
352 		skprovider = NULL; /* Don't send constraint for other keys */
353 	else if (skprovider == NULL) {
354 		fprintf(stderr, "Cannot load authenticator-hosted key %s "
355 		    "without provider\n", filename);
356 		goto out;
357 	}
358 
359 	if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
360 	    lifetime, confirm, maxsign, skprovider)) == 0) {
361 		ret = 0;
362 		if (!qflag) {
363 			fprintf(stderr, "Identity added: %s (%s)\n",
364 			    filename, comment);
365 			if (lifetime != 0) {
366 				fprintf(stderr,
367 				    "Lifetime set to %ld seconds\n", lifetime);
368 			}
369 			if (confirm != 0) {
370 				fprintf(stderr, "The user must confirm "
371 				    "each use of the key\n");
372 			}
373 		}
374 	} else {
375 		fprintf(stderr, "Could not add identity \"%s\": %s\n",
376 		    filename, ssh_err(r));
377 	}
378 
379 	/* Skip trying to load the cert if requested */
380 	if (key_only)
381 		goto out;
382 
383 	/* Now try to add the certificate flavour too */
384 	xasprintf(&certpath, "%s-cert.pub", filename);
385 	if ((r = sshkey_load_public(certpath, &cert, NULL)) != 0) {
386 		if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
387 			error("Failed to load certificate \"%s\": %s",
388 			    certpath, ssh_err(r));
389 		goto out;
390 	}
391 
392 	if (!sshkey_equal_public(cert, private)) {
393 		error("Certificate %s does not match private key %s",
394 		    certpath, filename);
395 		sshkey_free(cert);
396 		goto out;
397 	}
398 
399 	/* Graft with private bits */
400 	if ((r = sshkey_to_certified(private)) != 0) {
401 		error("%s: sshkey_to_certified: %s", __func__, ssh_err(r));
402 		sshkey_free(cert);
403 		goto out;
404 	}
405 	if ((r = sshkey_cert_copy(cert, private)) != 0) {
406 		error("%s: sshkey_cert_copy: %s", __func__, ssh_err(r));
407 		sshkey_free(cert);
408 		goto out;
409 	}
410 	sshkey_free(cert);
411 
412 	if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
413 	    lifetime, confirm, maxsign, skprovider)) != 0) {
414 		error("Certificate %s (%s) add failed: %s", certpath,
415 		    private->cert->key_id, ssh_err(r));
416 		goto out;
417 	}
418 	/* success */
419 	if (!qflag) {
420 		fprintf(stderr, "Certificate added: %s (%s)\n", certpath,
421 		    private->cert->key_id);
422 		if (lifetime != 0) {
423 			fprintf(stderr, "Lifetime set to %ld seconds\n",
424 			    lifetime);
425 		}
426 		if (confirm != 0) {
427 			fprintf(stderr, "The user must confirm each use "
428 			    "of the key\n");
429 		}
430 	}
431 
432  out:
433 	free(certpath);
434 	free(comment);
435 	sshkey_free(private);
436 
437 	return ret;
438 }
439 
440 static int
441 update_card(int agent_fd, int add, const char *id, int qflag)
442 {
443 	char *pin = NULL;
444 	int r, ret = -1;
445 
446 	if (add) {
447 		if ((pin = read_passphrase("Enter passphrase for PKCS#11: ",
448 		    RP_ALLOW_STDIN)) == NULL)
449 			return -1;
450 	}
451 
452 	if ((r = ssh_update_card(agent_fd, add, id, pin == NULL ? "" : pin,
453 	    lifetime, confirm)) == 0) {
454 		ret = 0;
455 		if (!qflag) {
456 			fprintf(stderr, "Card %s: %s\n",
457 			    add ? "added" : "removed", id);
458 		}
459 	} else {
460 		fprintf(stderr, "Could not %s card \"%s\": %s\n",
461 		    add ? "add" : "remove", id, ssh_err(r));
462 		ret = -1;
463 	}
464 	free(pin);
465 	return ret;
466 }
467 
468 static int
469 test_key(int agent_fd, const char *filename)
470 {
471 	struct sshkey *key = NULL;
472 	u_char *sig = NULL;
473 	size_t slen = 0;
474 	int r, ret = -1;
475 	char data[1024];
476 
477 	if ((r = sshkey_load_public(filename, &key, NULL)) != 0) {
478 		error("Couldn't read public key %s: %s", filename, ssh_err(r));
479 		return -1;
480 	}
481 	arc4random_buf(data, sizeof(data));
482 	if ((r = ssh_agent_sign(agent_fd, key, &sig, &slen, data, sizeof(data),
483 	    NULL, 0)) != 0) {
484 		error("Agent signature failed for %s: %s",
485 		    filename, ssh_err(r));
486 		goto done;
487 	}
488 	if ((r = sshkey_verify(key, sig, slen, data, sizeof(data),
489 	    NULL, 0, NULL)) != 0) {
490 		error("Signature verification failed for %s: %s",
491 		    filename, ssh_err(r));
492 		goto done;
493 	}
494 	/* success */
495 	ret = 0;
496  done:
497 	free(sig);
498 	sshkey_free(key);
499 	return ret;
500 }
501 
502 static int
503 list_identities(int agent_fd, int do_fp)
504 {
505 	char *fp;
506 	int r;
507 	struct ssh_identitylist *idlist;
508 	u_int32_t left;
509 	size_t i;
510 
511 	if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
512 		if (r != SSH_ERR_AGENT_NO_IDENTITIES)
513 			fprintf(stderr, "error fetching identities: %s\n",
514 			    ssh_err(r));
515 		else
516 			printf("The agent has no identities.\n");
517 		return -1;
518 	}
519 	for (i = 0; i < idlist->nkeys; i++) {
520 		if (do_fp) {
521 			fp = sshkey_fingerprint(idlist->keys[i],
522 			    fingerprint_hash, SSH_FP_DEFAULT);
523 			printf("%u %s %s (%s)\n", sshkey_size(idlist->keys[i]),
524 			    fp == NULL ? "(null)" : fp, idlist->comments[i],
525 			    sshkey_type(idlist->keys[i]));
526 			free(fp);
527 		} else {
528 			if ((r = sshkey_write(idlist->keys[i], stdout)) != 0) {
529 				fprintf(stderr, "sshkey_write: %s\n",
530 				    ssh_err(r));
531 				continue;
532 			}
533 			fprintf(stdout, " %s", idlist->comments[i]);
534 			left = sshkey_signatures_left(idlist->keys[i]);
535 			if (left > 0)
536 				fprintf(stdout,
537 				    " [signatures left %d]", left);
538 			fprintf(stdout, "\n");
539 		}
540 	}
541 	ssh_free_identitylist(idlist);
542 	return 0;
543 }
544 
545 static int
546 lock_agent(int agent_fd, int lock)
547 {
548 	char prompt[100], *p1, *p2;
549 	int r, passok = 1, ret = -1;
550 
551 	strlcpy(prompt, "Enter lock password: ", sizeof(prompt));
552 	p1 = read_passphrase(prompt, RP_ALLOW_STDIN);
553 	if (lock) {
554 		strlcpy(prompt, "Again: ", sizeof prompt);
555 		p2 = read_passphrase(prompt, RP_ALLOW_STDIN);
556 		if (strcmp(p1, p2) != 0) {
557 			fprintf(stderr, "Passwords do not match.\n");
558 			passok = 0;
559 		}
560 		freezero(p2, strlen(p2));
561 	}
562 	if (passok) {
563 		if ((r = ssh_lock_agent(agent_fd, lock, p1)) == 0) {
564 			fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un");
565 			ret = 0;
566 		} else {
567 			fprintf(stderr, "Failed to %slock agent: %s\n",
568 			    lock ? "" : "un", ssh_err(r));
569 		}
570 	}
571 	freezero(p1, strlen(p1));
572 	return (ret);
573 }
574 
575 static int
576 load_resident_keys(int agent_fd, const char *skprovider, int qflag)
577 {
578 	struct sshkey **keys;
579 	size_t nkeys, i;
580 	int r, ok = 0;
581 	char *fp;
582 
583 	pass = read_passphrase("Enter PIN for authenticator: ", RP_ALLOW_STDIN);
584 	if ((r = sshsk_load_resident(skprovider, NULL, pass,
585 	    &keys, &nkeys)) != 0) {
586 		error("Unable to load resident keys: %s", ssh_err(r));
587 		return r;
588 	}
589 	for (i = 0; i < nkeys; i++) {
590 		if ((fp = sshkey_fingerprint(keys[i],
591 		    fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
592 			fatal("%s: sshkey_fingerprint failed", __func__);
593 		if ((r = ssh_add_identity_constrained(agent_fd, keys[i], "",
594 		    lifetime, confirm, maxsign, skprovider)) != 0) {
595 			error("Unable to add key %s %s",
596 			    sshkey_type(keys[i]), fp);
597 			free(fp);
598 			ok = r;
599 			continue;
600 		}
601 		if (ok == 0)
602 			ok = 1;
603 		if (!qflag) {
604 			fprintf(stderr, "Resident identity added: %s %s\n",
605 			    sshkey_type(keys[i]), fp);
606 			if (lifetime != 0) {
607 				fprintf(stderr,
608 				    "Lifetime set to %ld seconds\n", lifetime);
609 			}
610 			if (confirm != 0) {
611 				fprintf(stderr, "The user must confirm "
612 				    "each use of the key\n");
613 			}
614 		}
615 		free(fp);
616 		sshkey_free(keys[i]);
617 	}
618 	free(keys);
619 	if (nkeys == 0)
620 		return SSH_ERR_KEY_NOT_FOUND;
621 	return ok == 1 ? 0 : ok;
622 }
623 
624 static int
625 do_file(int agent_fd, int deleting, int key_only, char *file, int qflag,
626     const char *skprovider)
627 {
628 	if (deleting) {
629 		if (delete_file(agent_fd, file, key_only, qflag) == -1)
630 			return -1;
631 	} else {
632 		if (add_file(agent_fd, file, key_only, qflag, skprovider) == -1)
633 			return -1;
634 	}
635 	return 0;
636 }
637 
638 static void
639 usage(void)
640 {
641 	fprintf(stderr,
642 "usage: ssh-add [-cDdKkLlqvXx] [-E fingerprint_hash] [-S provider] [-t life]\n"
643 #ifdef WITH_XMSS
644 "               [-M maxsign] [-m minleft]\n"
645 #endif
646 "               [file ...]\n"
647 "       ssh-add -s pkcs11\n"
648 "       ssh-add -e pkcs11\n"
649 "       ssh-add -T pubkey ...\n"
650 	);
651 }
652 
653 int
654 main(int argc, char **argv)
655 {
656 	extern char *optarg;
657 	extern int optind;
658 	int agent_fd;
659 	char *pkcs11provider = NULL, *skprovider = NULL;
660 	int r, i, ch, deleting = 0, ret = 0, key_only = 0, do_download = 0;
661 	int xflag = 0, lflag = 0, Dflag = 0, qflag = 0, Tflag = 0;
662 	SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
663 	LogLevel log_level = SYSLOG_LEVEL_INFO;
664 
665 	/* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
666 	sanitise_stdfd();
667 
668 	__progname = ssh_get_progname(argv[0]);
669 	seed_rng();
670 
671 	log_init(__progname, log_level, log_facility, 1);
672 
673 	setvbuf(stdout, NULL, _IOLBF, 0);
674 
675 	/* First, get a connection to the authentication agent. */
676 	switch (r = ssh_get_authentication_socket(&agent_fd)) {
677 	case 0:
678 		break;
679 	case SSH_ERR_AGENT_NOT_PRESENT:
680 		fprintf(stderr, "Could not open a connection to your "
681 		    "authentication agent.\n");
682 		exit(2);
683 	default:
684 		fprintf(stderr, "Error connecting to agent: %s\n", ssh_err(r));
685 		exit(2);
686 	}
687 
688 	skprovider = getenv("SSH_SK_PROVIDER");
689 
690 	while ((ch = getopt(argc, argv, "vkKlLcdDTxXE:e:M:m:qs:S:t:")) != -1) {
691 		switch (ch) {
692 		case 'v':
693 			if (log_level == SYSLOG_LEVEL_INFO)
694 				log_level = SYSLOG_LEVEL_DEBUG1;
695 			else if (log_level < SYSLOG_LEVEL_DEBUG3)
696 				log_level++;
697 			break;
698 		case 'E':
699 			fingerprint_hash = ssh_digest_alg_by_name(optarg);
700 			if (fingerprint_hash == -1)
701 				fatal("Invalid hash algorithm \"%s\"", optarg);
702 			break;
703 		case 'k':
704 			key_only = 1;
705 			break;
706 		case 'K':
707 			do_download = 1;
708 			break;
709 		case 'l':
710 		case 'L':
711 			if (lflag != 0)
712 				fatal("-%c flag already specified", lflag);
713 			lflag = ch;
714 			break;
715 		case 'x':
716 		case 'X':
717 			if (xflag != 0)
718 				fatal("-%c flag already specified", xflag);
719 			xflag = ch;
720 			break;
721 		case 'c':
722 			confirm = 1;
723 			break;
724 		case 'm':
725 			minleft = (int)strtonum(optarg, 1, UINT_MAX, NULL);
726 			if (minleft == 0) {
727 				usage();
728 				ret = 1;
729 				goto done;
730 			}
731 			break;
732 		case 'M':
733 			maxsign = (int)strtonum(optarg, 1, UINT_MAX, NULL);
734 			if (maxsign == 0) {
735 				usage();
736 				ret = 1;
737 				goto done;
738 			}
739 			break;
740 		case 'd':
741 			deleting = 1;
742 			break;
743 		case 'D':
744 			Dflag = 1;
745 			break;
746 		case 's':
747 			pkcs11provider = optarg;
748 			break;
749 		case 'S':
750 			skprovider = optarg;
751 			break;
752 		case 'e':
753 			deleting = 1;
754 			pkcs11provider = optarg;
755 			break;
756 		case 't':
757 			if ((lifetime = convtime(optarg)) == -1 ||
758 			    lifetime < 0 || (u_long)lifetime > UINT32_MAX) {
759 				fprintf(stderr, "Invalid lifetime\n");
760 				ret = 1;
761 				goto done;
762 			}
763 			break;
764 		case 'q':
765 			qflag = 1;
766 			break;
767 		case 'T':
768 			Tflag = 1;
769 			break;
770 		default:
771 			usage();
772 			ret = 1;
773 			goto done;
774 		}
775 	}
776 	log_init(__progname, log_level, log_facility, 1);
777 
778 	if ((xflag != 0) + (lflag != 0) + (Dflag != 0) > 1)
779 		fatal("Invalid combination of actions");
780 	else if (xflag) {
781 		if (lock_agent(agent_fd, xflag == 'x' ? 1 : 0) == -1)
782 			ret = 1;
783 		goto done;
784 	} else if (lflag) {
785 		if (list_identities(agent_fd, lflag == 'l' ? 1 : 0) == -1)
786 			ret = 1;
787 		goto done;
788 	} else if (Dflag) {
789 		if (delete_all(agent_fd, qflag) == -1)
790 			ret = 1;
791 		goto done;
792 	}
793 
794 #ifdef ENABLE_SK_INTERNAL
795 	if (skprovider == NULL)
796 		skprovider = "internal";
797 #endif
798 
799 	argc -= optind;
800 	argv += optind;
801 	if (Tflag) {
802 		if (argc <= 0)
803 			fatal("no keys to test");
804 		for (r = i = 0; i < argc; i++)
805 			r |= test_key(agent_fd, argv[i]);
806 		ret = r == 0 ? 0 : 1;
807 		goto done;
808 	}
809 	if (pkcs11provider != NULL) {
810 		if (update_card(agent_fd, !deleting, pkcs11provider,
811 		    qflag) == -1)
812 			ret = 1;
813 		goto done;
814 	}
815 	if (do_download) {
816 		if (skprovider == NULL)
817 			fatal("Cannot download keys without provider");
818 		if (load_resident_keys(agent_fd, skprovider, qflag) != 0)
819 			ret = 1;
820 		goto done;
821 	}
822 	if (argc == 0) {
823 		char buf[PATH_MAX];
824 		struct passwd *pw;
825 		struct stat st;
826 		int count = 0;
827 
828 		if ((pw = getpwuid(getuid())) == NULL) {
829 			fprintf(stderr, "No user found with uid %u\n",
830 			    (u_int)getuid());
831 			ret = 1;
832 			goto done;
833 		}
834 
835 		for (i = 0; default_files[i]; i++) {
836 			snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir,
837 			    default_files[i]);
838 			if (stat(buf, &st) == -1)
839 				continue;
840 			if (do_file(agent_fd, deleting, key_only, buf,
841 			    qflag, skprovider) == -1)
842 				ret = 1;
843 			else
844 				count++;
845 		}
846 		if (count == 0)
847 			ret = 1;
848 	} else {
849 		for (i = 0; i < argc; i++) {
850 			if (do_file(agent_fd, deleting, key_only,
851 			    argv[i], qflag, skprovider) == -1)
852 				ret = 1;
853 		}
854 	}
855 done:
856 	clear_pass();
857 	ssh_close_authentication_socket(agent_fd);
858 	return ret;
859 }
860