xref: /freebsd/crypto/openssh/ssh-add.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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"
38 RCSID("$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
54 extern char *__progname;
55 #else
56 char *__progname;
57 #endif
58 
59 /* argv0 */
60 extern char *__progname;
61 
62 /* Default files to add */
63 static 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) */
71 static int lifetime = 0;
72 
73 /* User has to confirm key use */
74 static int confirm = 0;
75 
76 /* we keep a cache of one passphrases */
77 static char *pass = NULL;
78 static void
79 clear_pass(void)
80 {
81 	if (pass) {
82 		memset(pass, 0, strlen(pass));
83 		xfree(pass);
84 		pass = NULL;
85 	}
86 }
87 
88 static int
89 delete_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. */
113 static int
114 delete_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 
131 static int
132 add_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 
194 static int
195 update_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 
217 static int
218 list_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 
252 static int
253 lock_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 
280 static int
281 do_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 
293 static void
294 usage(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 
312 int
313 main(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 
418 done:
419 	ssh_close_authentication_connection(ac);
420 	return ret;
421 }
422