ssh-add.c revision 114426 
1/*
2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 *                    All rights reserved
5 * Adds an identity to the authentication server, or removes an identity.
6 *
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose.  Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
12 *
13 * SSH2 implementation,
14 * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 *    notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 *    notice, this list of conditions and the following disclaimer in the
23 *    documentation and/or other materials provided with the distribution.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "includes.h"
38RCSID("$OpenBSD: ssh-add.c,v 1.66 2003/03/05 22:33:43 markus Exp $");
39
40#include <openssl/evp.h>
41
42#include "ssh.h"
43#include "rsa.h"
44#include "log.h"
45#include "xmalloc.h"
46#include "key.h"
47#include "authfd.h"
48#include "authfile.h"
49#include "pathnames.h"
50#include "readpass.h"
51#include "misc.h"
52
53#ifdef HAVE___PROGNAME
54extern char *__progname;
55#else
56char *__progname;
57#endif
58
59/* argv0 */
60extern char *__progname;
61
62/* Default files to add */
63static char *default_files[] = {
64	_PATH_SSH_CLIENT_ID_RSA,
65	_PATH_SSH_CLIENT_ID_DSA,
66	_PATH_SSH_CLIENT_IDENTITY,
67	NULL
68};
69
70/* Default lifetime (0 == forever) */
71static int lifetime = 0;
72
73/* User has to confirm key use */
74static int confirm = 0;
75
76/* we keep a cache of one passphrases */
77static char *pass = NULL;
78static void
79clear_pass(void)
80{
81	if (pass) {
82		memset(pass, 0, strlen(pass));
83		xfree(pass);
84		pass = NULL;
85	}
86}
87
88static int
89delete_file(AuthenticationConnection *ac, const char *filename)
90{
91	Key *public;
92	char *comment = NULL;
93	int ret = -1;
94
95	public = key_load_public(filename, &comment);
96	if (public == NULL) {
97		printf("Bad key file %s\n", filename);
98		return -1;
99	}
100	if (ssh_remove_identity(ac, public)) {
101		fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment);
102		ret = 0;
103	} else
104		fprintf(stderr, "Could not remove identity: %s\n", filename);
105
106	key_free(public);
107	xfree(comment);
108
109	return ret;
110}
111
112/* Send a request to remove all identities. */
113static int
114delete_all(AuthenticationConnection *ac)
115{
116	int ret = -1;
117
118	if (ssh_remove_all_identities(ac, 1))
119		ret = 0;
120	/* ignore error-code for ssh2 */
121	ssh_remove_all_identities(ac, 2);
122
123	if (ret == 0)
124		fprintf(stderr, "All identities removed.\n");
125	else
126		fprintf(stderr, "Failed to remove all identities.\n");
127
128	return ret;
129}
130
131static int
132add_file(AuthenticationConnection *ac, const char *filename)
133{
134	struct stat st;
135	Key *private;
136	char *comment = NULL;
137	char msg[1024];
138	int ret = -1;
139
140	if (stat(filename, &st) < 0) {
141		perror(filename);
142		return -1;
143	}
144	/* At first, try empty passphrase */
145	private = key_load_private(filename, "", &comment);
146	if (comment == NULL)
147		comment = xstrdup(filename);
148	/* try last */
149	if (private == NULL && pass != NULL)
150		private = key_load_private(filename, pass, NULL);
151	if (private == NULL) {
152		/* clear passphrase since it did not work */
153		clear_pass();
154		snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ",
155		   comment);
156		for (;;) {
157			pass = read_passphrase(msg, RP_ALLOW_STDIN);
158			if (strcmp(pass, "") == 0) {
159				clear_pass();
160				xfree(comment);
161				return -1;
162			}
163			private = key_load_private(filename, pass, &comment);
164			if (private != NULL)
165				break;
166			clear_pass();
167			strlcpy(msg, "Bad passphrase, try again: ", sizeof msg);
168		}
169	}
170
171 	if (ssh_add_identity_constrained(ac, private, comment, lifetime,
172 	    confirm)) {
173		fprintf(stderr, "Identity added: %s (%s)\n", filename, comment);
174		ret = 0;
175		if (lifetime != 0)
176			fprintf(stderr,
177			    "Lifetime set to %d seconds\n", lifetime);
178 		if (confirm != 0)
179			fprintf(stderr,
180			    "The user has to confirm each use of the key\n");
181	} else if (ssh_add_identity(ac, private, comment)) {
182		fprintf(stderr, "Identity added: %s (%s)\n", filename, comment);
183		ret = 0;
184	} else {
185		fprintf(stderr, "Could not add identity: %s\n", filename);
186	}
187
188	xfree(comment);
189	key_free(private);
190
191	return ret;
192}
193
194static int
195update_card(AuthenticationConnection *ac, int add, const char *id)
196{
197	char *pin;
198	int ret = -1;
199
200	pin = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN);
201	if (pin == NULL)
202		return -1;
203
204	if (ssh_update_card(ac, add, id, pin)) {
205		fprintf(stderr, "Card %s: %s\n",
206		    add ? "added" : "removed", id);
207		ret = 0;
208	} else {
209		fprintf(stderr, "Could not %s card: %s\n",
210		    add ? "add" : "remove", id);
211		ret = -1;
212	}
213	xfree(pin);
214	return ret;
215}
216
217static int
218list_identities(AuthenticationConnection *ac, int do_fp)
219{
220	Key *key;
221	char *comment, *fp;
222	int had_identities = 0;
223	int version;
224
225	for (version = 1; version <= 2; version++) {
226		for (key = ssh_get_first_identity(ac, &comment, version);
227		    key != NULL;
228		    key = ssh_get_next_identity(ac, &comment, version)) {
229			had_identities = 1;
230			if (do_fp) {
231				fp = key_fingerprint(key, SSH_FP_MD5,
232				    SSH_FP_HEX);
233				printf("%d %s %s (%s)\n",
234				    key_size(key), fp, comment, key_type(key));
235				xfree(fp);
236			} else {
237				if (!key_write(key, stdout))
238					fprintf(stderr, "key_write failed");
239				fprintf(stdout, " %s\n", comment);
240			}
241			key_free(key);
242			xfree(comment);
243		}
244	}
245	if (!had_identities) {
246		printf("The agent has no identities.\n");
247		return -1;
248	}
249	return 0;
250}
251
252static int
253lock_agent(AuthenticationConnection *ac, int lock)
254{
255	char prompt[100], *p1, *p2;
256	int passok = 1, ret = -1;
257
258	strlcpy(prompt, "Enter lock password: ", sizeof(prompt));
259	p1 = read_passphrase(prompt, RP_ALLOW_STDIN);
260	if (lock) {
261		strlcpy(prompt, "Again: ", sizeof prompt);
262		p2 = read_passphrase(prompt, RP_ALLOW_STDIN);
263		if (strcmp(p1, p2) != 0) {
264			fprintf(stderr, "Passwords do not match.\n");
265			passok = 0;
266		}
267		memset(p2, 0, strlen(p2));
268		xfree(p2);
269	}
270	if (passok && ssh_lock_agent(ac, lock, p1)) {
271		fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un");
272		ret = 0;
273	} else
274		fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un");
275	memset(p1, 0, strlen(p1));
276	xfree(p1);
277	return (ret);
278}
279
280static int
281do_file(AuthenticationConnection *ac, int deleting, char *file)
282{
283	if (deleting) {
284		if (delete_file(ac, file) == -1)
285			return -1;
286	} else {
287		if (add_file(ac, file) == -1)
288			return -1;
289	}
290	return 0;
291}
292
293static void
294usage(void)
295{
296	fprintf(stderr, "Usage: %s [options]\n", __progname);
297	fprintf(stderr, "Options:\n");
298	fprintf(stderr, "  -l          List fingerprints of all identities.\n");
299	fprintf(stderr, "  -L          List public key parameters of all identities.\n");
300	fprintf(stderr, "  -d          Delete identity.\n");
301	fprintf(stderr, "  -D          Delete all identities.\n");
302	fprintf(stderr, "  -x          Lock agent.\n");
303	fprintf(stderr, "  -X          Unlock agent.\n");
304	fprintf(stderr, "  -t life     Set lifetime (in seconds) when adding identities.\n");
305	fprintf(stderr, "  -c          Require confirmation to sign using identities\n");
306#ifdef SMARTCARD
307	fprintf(stderr, "  -s reader   Add key in smartcard reader.\n");
308	fprintf(stderr, "  -e reader   Remove key in smartcard reader.\n");
309#endif
310}
311
312int
313main(int argc, char **argv)
314{
315	extern char *optarg;
316	extern int optind;
317	AuthenticationConnection *ac = NULL;
318	char *sc_reader_id = NULL;
319	int i, ch, deleting = 0, ret = 0;
320
321	__progname = get_progname(argv[0]);
322	init_rng();
323	seed_rng();
324
325	SSLeay_add_all_algorithms();
326
327	/* At first, get a connection to the authentication agent. */
328	ac = ssh_get_authentication_connection();
329	if (ac == NULL) {
330		fprintf(stderr, "Could not open a connection to your authentication agent.\n");
331		exit(2);
332	}
333	while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) {
334		switch (ch) {
335		case 'l':
336		case 'L':
337			if (list_identities(ac, ch == 'l' ? 1 : 0) == -1)
338				ret = 1;
339			goto done;
340			break;
341		case 'x':
342		case 'X':
343			if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1)
344				ret = 1;
345			goto done;
346			break;
347		case 'c':
348			confirm = 1;
349			break;
350		case 'd':
351			deleting = 1;
352			break;
353		case 'D':
354			if (delete_all(ac) == -1)
355				ret = 1;
356			goto done;
357			break;
358		case 's':
359			sc_reader_id = optarg;
360			break;
361		case 'e':
362			deleting = 1;
363			sc_reader_id = optarg;
364			break;
365		case 't':
366			if ((lifetime = convtime(optarg)) == -1) {
367				fprintf(stderr, "Invalid lifetime\n");
368				ret = 1;
369				goto done;
370			}
371			break;
372		default:
373			usage();
374			ret = 1;
375			goto done;
376		}
377	}
378	argc -= optind;
379	argv += optind;
380	if (sc_reader_id != NULL) {
381		if (update_card(ac, !deleting, sc_reader_id) == -1)
382			ret = 1;
383		goto done;
384	}
385	if (argc == 0) {
386		char buf[MAXPATHLEN];
387		struct passwd *pw;
388		struct stat st;
389		int count = 0;
390
391		if ((pw = getpwuid(getuid())) == NULL) {
392			fprintf(stderr, "No user found with uid %u\n",
393			    (u_int)getuid());
394			ret = 1;
395			goto done;
396		}
397
398		for(i = 0; default_files[i]; i++) {
399			snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir,
400			    default_files[i]);
401			if (stat(buf, &st) < 0)
402				continue;
403			if (do_file(ac, deleting, buf) == -1)
404				ret = 1;
405			else
406				count++;
407		}
408		if (count == 0)
409			ret = 1;
410	} else {
411		for(i = 0; i < argc; i++) {
412			if (do_file(ac, deleting, argv[i]) == -1)
413				ret = 1;
414		}
415	}
416	clear_pass();
417
418done:
419	ssh_close_authentication_connection(ac);
420	return ret;
421}
422