1 /* $OpenBSD: ssh-add.c,v 1.138 2019/01/21 12:53:35 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * Adds an identity to the authentication server, or removes an identity.
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".
14 * SSH2 implementation,
15 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
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.
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.
40 #include <sys/types.h>
43 #include <openssl/evp.h>
44 #include "openbsd-compat/openssl-compat.h"
63 #include "pathnames.h"
69 extern char *__progname;
71 /* Default files to add */
72 static char *default_files[] = {
74 _PATH_SSH_CLIENT_ID_RSA,
75 _PATH_SSH_CLIENT_ID_DSA,
76 #ifdef OPENSSL_HAS_ECC
77 _PATH_SSH_CLIENT_ID_ECDSA,
79 #endif /* WITH_OPENSSL */
80 _PATH_SSH_CLIENT_ID_ED25519,
81 _PATH_SSH_CLIENT_ID_XMSS,
85 static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
87 /* Default lifetime (0 == forever) */
88 static int lifetime = 0;
90 /* User has to confirm key use */
91 static int confirm = 0;
93 /* Maximum number of signatures (XMSS) */
94 static u_int maxsign = 0;
95 static u_int minleft = 0;
97 /* we keep a cache of one passphrase */
98 static char *pass = NULL;
103 explicit_bzero(pass, strlen(pass));
110 delete_file(int agent_fd, const char *filename, int key_only, int qflag)
112 struct sshkey *public, *cert = NULL;
113 char *certpath = NULL, *comment = NULL;
116 if ((r = sshkey_load_public(filename, &public, &comment)) != 0) {
117 printf("Bad key file %s: %s\n", filename, ssh_err(r));
120 if ((r = ssh_remove_identity(agent_fd, public)) == 0) {
122 fprintf(stderr, "Identity removed: %s (%s)\n",
127 fprintf(stderr, "Could not remove identity \"%s\": %s\n",
128 filename, ssh_err(r));
133 /* Now try to delete the corresponding certificate too */
136 xasprintf(&certpath, "%s-cert.pub", filename);
137 if ((r = sshkey_load_public(certpath, &cert, &comment)) != 0) {
138 if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
139 error("Failed to load certificate \"%s\": %s",
140 certpath, ssh_err(r));
144 if (!sshkey_equal_public(cert, public))
145 fatal("Certificate %s does not match private key %s",
148 if ((r = ssh_remove_identity(agent_fd, cert)) == 0) {
150 fprintf(stderr, "Identity removed: %s (%s)\n",
155 fprintf(stderr, "Could not remove identity \"%s\": %s\n",
156 certpath, ssh_err(r));
167 /* Send a request to remove all identities. */
169 delete_all(int agent_fd, int qflag)
174 * Since the agent might be forwarded, old or non-OpenSSH, when asked
175 * to remove all keys, attempt to remove both protocol v.1 and v.2
178 if (ssh_remove_all_identities(agent_fd, 2) == 0)
180 /* ignore error-code for ssh1 */
181 ssh_remove_all_identities(agent_fd, 1);
184 fprintf(stderr, "Failed to remove all identities.\n");
186 fprintf(stderr, "All identities removed.\n");
192 add_file(int agent_fd, const char *filename, int key_only, int qflag)
194 struct sshkey *private, *cert;
195 char *comment = NULL;
196 char msg[1024], *certpath = NULL;
200 struct sshbuf *keyblob;
201 struct ssh_identitylist *idlist;
203 if (strcmp(filename, "-") == 0) {
205 filename = "(stdin)";
206 } else if ((fd = open(filename, O_RDONLY)) < 0) {
212 * Since we'll try to load a keyfile multiple times, permission errors
213 * will occur multiple times, so check perms first and bail if wrong.
215 if (fd != STDIN_FILENO) {
216 if (sshkey_perm_ok(fd, filename) != 0) {
221 if ((keyblob = sshbuf_new()) == NULL)
222 fatal("%s: sshbuf_new failed", __func__);
223 if ((r = sshkey_load_file(fd, keyblob)) != 0) {
224 fprintf(stderr, "Error loading key \"%s\": %s\n",
225 filename, ssh_err(r));
226 sshbuf_free(keyblob);
232 /* At first, try empty passphrase */
233 if ((r = sshkey_parse_private_fileblob(keyblob, "", &private,
234 &comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
235 fprintf(stderr, "Error loading key \"%s\": %s\n",
236 filename, ssh_err(r));
240 if (private == NULL && pass != NULL) {
241 if ((r = sshkey_parse_private_fileblob(keyblob, pass, &private,
242 &comment)) != 0 && r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
243 fprintf(stderr, "Error loading key \"%s\": %s\n",
244 filename, ssh_err(r));
248 if (private == NULL) {
249 /* clear passphrase since it did not work */
251 snprintf(msg, sizeof msg, "Enter passphrase for %s%s: ",
252 filename, confirm ? " (will confirm each use)" : "");
254 pass = read_passphrase(msg, RP_ALLOW_STDIN);
255 if (strcmp(pass, "") == 0)
257 if ((r = sshkey_parse_private_fileblob(keyblob, pass,
258 &private, &comment)) == 0)
260 else if (r != SSH_ERR_KEY_WRONG_PASSPHRASE) {
262 "Error loading key \"%s\": %s\n",
263 filename, ssh_err(r));
266 sshbuf_free(keyblob);
270 snprintf(msg, sizeof msg,
271 "Bad passphrase, try again for %s%s: ", filename,
272 confirm ? " (will confirm each use)" : "");
275 if (comment == NULL || *comment == '\0')
276 comment = xstrdup(filename);
277 sshbuf_free(keyblob);
280 if ((r = sshkey_set_filename(private, filename)) != 0) {
281 fprintf(stderr, "Could not add filename to private key: %s (%s)\n",
285 if (maxsign && minleft &&
286 (r = ssh_fetch_identitylist(agent_fd, &idlist)) == 0) {
287 for (i = 0; i < idlist->nkeys; i++) {
288 if (!sshkey_equal_public(idlist->keys[i], private))
290 left = sshkey_signatures_left(idlist->keys[i]);
291 if (left < minleft) {
293 "Only %d signatures left.\n", left);
296 fprintf(stderr, "Skipping update: ");
297 if (left == minleft) {
299 "required signatures left (%d).\n", left);
302 "more signatures left (%d) than"
303 " required (%d).\n", left, minleft);
305 ssh_free_identitylist(idlist);
308 ssh_free_identitylist(idlist);
311 if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
312 lifetime, confirm, maxsign)) == 0) {
315 fprintf(stderr, "Identity added: %s (%s)\n",
319 "Lifetime set to %d seconds\n", lifetime);
322 fprintf(stderr, "The user must confirm "
323 "each use of the key\n");
327 fprintf(stderr, "Could not add identity \"%s\": %s\n",
328 filename, ssh_err(r));
331 /* Skip trying to load the cert if requested */
335 /* Now try to add the certificate flavour too */
336 xasprintf(&certpath, "%s-cert.pub", filename);
337 if ((r = sshkey_load_public(certpath, &cert, NULL)) != 0) {
338 if (r != SSH_ERR_SYSTEM_ERROR || errno != ENOENT)
339 error("Failed to load certificate \"%s\": %s",
340 certpath, ssh_err(r));
344 if (!sshkey_equal_public(cert, private)) {
345 error("Certificate %s does not match private key %s",
351 /* Graft with private bits */
352 if ((r = sshkey_to_certified(private)) != 0) {
353 error("%s: sshkey_to_certified: %s", __func__, ssh_err(r));
357 if ((r = sshkey_cert_copy(cert, private)) != 0) {
358 error("%s: sshkey_cert_copy: %s", __func__, ssh_err(r));
364 if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
365 lifetime, confirm, maxsign)) != 0) {
366 error("Certificate %s (%s) add failed: %s", certpath,
367 private->cert->key_id, ssh_err(r));
372 fprintf(stderr, "Certificate added: %s (%s)\n", certpath,
373 private->cert->key_id);
375 fprintf(stderr, "Lifetime set to %d seconds\n",
379 fprintf(stderr, "The user must confirm each use "
387 sshkey_free(private);
393 update_card(int agent_fd, int add, const char *id, int qflag)
399 if ((pin = read_passphrase("Enter passphrase for PKCS#11: ",
400 RP_ALLOW_STDIN)) == NULL)
404 if ((r = ssh_update_card(agent_fd, add, id, pin == NULL ? "" : pin,
405 lifetime, confirm)) == 0) {
408 fprintf(stderr, "Card %s: %s\n",
409 add ? "added" : "removed", id);
412 fprintf(stderr, "Could not %s card \"%s\": %s\n",
413 add ? "add" : "remove", id, ssh_err(r));
421 test_key(int agent_fd, const char *filename)
423 struct sshkey *key = NULL;
429 if ((r = sshkey_load_public(filename, &key, NULL)) != 0) {
430 error("Couldn't read public key %s: %s", filename, ssh_err(r));
433 arc4random_buf(data, sizeof(data));
434 if ((r = ssh_agent_sign(agent_fd, key, &sig, &slen, data, sizeof(data),
436 error("Agent signature failed for %s: %s",
437 filename, ssh_err(r));
440 if ((r = sshkey_verify(key, sig, slen, data, sizeof(data),
442 error("Signature verification failed for %s: %s",
443 filename, ssh_err(r));
455 list_identities(int agent_fd, int do_fp)
459 struct ssh_identitylist *idlist;
463 if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
464 if (r != SSH_ERR_AGENT_NO_IDENTITIES)
465 fprintf(stderr, "error fetching identities: %s\n",
468 printf("The agent has no identities.\n");
471 for (i = 0; i < idlist->nkeys; i++) {
473 fp = sshkey_fingerprint(idlist->keys[i],
474 fingerprint_hash, SSH_FP_DEFAULT);
475 printf("%u %s %s (%s)\n", sshkey_size(idlist->keys[i]),
476 fp == NULL ? "(null)" : fp, idlist->comments[i],
477 sshkey_type(idlist->keys[i]));
480 if ((r = sshkey_write(idlist->keys[i], stdout)) != 0) {
481 fprintf(stderr, "sshkey_write: %s\n",
485 fprintf(stdout, " %s", idlist->comments[i]);
486 left = sshkey_signatures_left(idlist->keys[i]);
489 " [signatures left %d]", left);
490 fprintf(stdout, "\n");
493 ssh_free_identitylist(idlist);
498 lock_agent(int agent_fd, int lock)
500 char prompt[100], *p1, *p2;
501 int r, passok = 1, ret = -1;
503 strlcpy(prompt, "Enter lock password: ", sizeof(prompt));
504 p1 = read_passphrase(prompt, RP_ALLOW_STDIN);
506 strlcpy(prompt, "Again: ", sizeof prompt);
507 p2 = read_passphrase(prompt, RP_ALLOW_STDIN);
508 if (strcmp(p1, p2) != 0) {
509 fprintf(stderr, "Passwords do not match.\n");
512 explicit_bzero(p2, strlen(p2));
516 if ((r = ssh_lock_agent(agent_fd, lock, p1)) == 0) {
517 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un");
520 fprintf(stderr, "Failed to %slock agent: %s\n",
521 lock ? "" : "un", ssh_err(r));
524 explicit_bzero(p1, strlen(p1));
530 do_file(int agent_fd, int deleting, int key_only, char *file, int qflag)
533 if (delete_file(agent_fd, file, key_only, qflag) == -1)
536 if (add_file(agent_fd, file, key_only, qflag) == -1)
545 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname);
546 fprintf(stderr, "Options:\n");
547 fprintf(stderr, " -l List fingerprints of all identities.\n");
548 fprintf(stderr, " -E hash Specify hash algorithm used for fingerprints.\n");
549 fprintf(stderr, " -L List public key parameters of all identities.\n");
550 fprintf(stderr, " -k Load only keys and not certificates.\n");
551 fprintf(stderr, " -c Require confirmation to sign using identities\n");
552 fprintf(stderr, " -m minleft Maxsign is only changed if less than minleft are left (for XMSS)\n");
553 fprintf(stderr, " -M maxsign Maximum number of signatures allowed (for XMSS)\n");
554 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n");
555 fprintf(stderr, " -d Delete identity.\n");
556 fprintf(stderr, " -D Delete all identities.\n");
557 fprintf(stderr, " -x Lock agent.\n");
558 fprintf(stderr, " -X Unlock agent.\n");
559 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n");
560 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n");
561 fprintf(stderr, " -T pubkey Test if ssh-agent can access matching private key.\n");
562 fprintf(stderr, " -q Be quiet after a successful operation.\n");
563 fprintf(stderr, " -v Be more verbose.\n");
567 main(int argc, char **argv)
572 char *pkcs11provider = NULL;
573 int r, i, ch, deleting = 0, ret = 0, key_only = 0;
574 int xflag = 0, lflag = 0, Dflag = 0, qflag = 0, Tflag = 0;
575 SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
576 LogLevel log_level = SYSLOG_LEVEL_INFO;
578 ssh_malloc_init(); /* must be called before any mallocs */
579 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
582 __progname = ssh_get_progname(argv[0]);
585 log_init(__progname, log_level, log_facility, 1);
587 setvbuf(stdout, NULL, _IOLBF, 0);
589 /* First, get a connection to the authentication agent. */
590 switch (r = ssh_get_authentication_socket(&agent_fd)) {
593 case SSH_ERR_AGENT_NOT_PRESENT:
594 fprintf(stderr, "Could not open a connection to your "
595 "authentication agent.\n");
598 fprintf(stderr, "Error connecting to agent: %s\n", ssh_err(r));
602 while ((ch = getopt(argc, argv, "vklLcdDTxXE:e:M:m:qs:t:")) != -1) {
605 if (log_level == SYSLOG_LEVEL_INFO)
606 log_level = SYSLOG_LEVEL_DEBUG1;
607 else if (log_level < SYSLOG_LEVEL_DEBUG3)
611 fingerprint_hash = ssh_digest_alg_by_name(optarg);
612 if (fingerprint_hash == -1)
613 fatal("Invalid hash algorithm \"%s\"", optarg);
621 fatal("-%c flag already specified", lflag);
627 fatal("-%c flag already specified", xflag);
634 minleft = (int)strtonum(optarg, 1, UINT_MAX, NULL);
642 maxsign = (int)strtonum(optarg, 1, UINT_MAX, NULL);
656 pkcs11provider = optarg;
660 pkcs11provider = optarg;
663 if ((lifetime = convtime(optarg)) == -1) {
664 fprintf(stderr, "Invalid lifetime\n");
681 log_init(__progname, log_level, log_facility, 1);
683 if ((xflag != 0) + (lflag != 0) + (Dflag != 0) > 1)
684 fatal("Invalid combination of actions");
686 if (lock_agent(agent_fd, xflag == 'x' ? 1 : 0) == -1)
690 if (list_identities(agent_fd, lflag == 'l' ? 1 : 0) == -1)
694 if (delete_all(agent_fd, qflag) == -1)
703 fatal("no keys to test");
704 for (r = i = 0; i < argc; i++)
705 r |= test_key(agent_fd, argv[i]);
706 ret = r == 0 ? 0 : 1;
709 if (pkcs11provider != NULL) {
710 if (update_card(agent_fd, !deleting, pkcs11provider,
721 if ((pw = getpwuid(getuid())) == NULL) {
722 fprintf(stderr, "No user found with uid %u\n",
728 for (i = 0; default_files[i]; i++) {
729 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir,
731 if (stat(buf, &st) < 0)
733 if (do_file(agent_fd, deleting, key_only, buf,
742 for (i = 0; i < argc; i++) {
743 if (do_file(agent_fd, deleting, key_only,
744 argv[i], qflag) == -1)
751 ssh_close_authentication_socket(agent_fd);