1 /* $OpenBSD: ssh-add.c,v 1.89 2006/08/03 03:34:42 deraadt 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 #include <sys/param.h> 43 44 #include <openssl/evp.h> 45 46 #include <fcntl.h> 47 #include <pwd.h> 48 #include <stdarg.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <unistd.h> 53 54 #include "xmalloc.h" 55 #include "ssh.h" 56 #include "rsa.h" 57 #include "log.h" 58 #include "key.h" 59 #include "buffer.h" 60 #include "authfd.h" 61 #include "authfile.h" 62 #include "pathnames.h" 63 #include "misc.h" 64 65 /* argv0 */ 66 extern char *__progname; 67 68 /* Default files to add */ 69 static char *default_files[] = { 70 _PATH_SSH_CLIENT_ID_RSA, 71 _PATH_SSH_CLIENT_ID_DSA, 72 _PATH_SSH_CLIENT_IDENTITY, 73 NULL 74 }; 75 76 /* Default lifetime (0 == forever) */ 77 static int lifetime = 0; 78 79 /* User has to confirm key use */ 80 static int confirm = 0; 81 82 /* we keep a cache of one passphrases */ 83 static char *pass = NULL; 84 static void 85 clear_pass(void) 86 { 87 if (pass) { 88 memset(pass, 0, strlen(pass)); 89 xfree(pass); 90 pass = NULL; 91 } 92 } 93 94 static int 95 delete_file(AuthenticationConnection *ac, const char *filename) 96 { 97 Key *public; 98 char *comment = NULL; 99 int ret = -1; 100 101 public = key_load_public(filename, &comment); 102 if (public == NULL) { 103 printf("Bad key file %s\n", filename); 104 return -1; 105 } 106 if (ssh_remove_identity(ac, public)) { 107 fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment); 108 ret = 0; 109 } else 110 fprintf(stderr, "Could not remove identity: %s\n", filename); 111 112 key_free(public); 113 xfree(comment); 114 115 return ret; 116 } 117 118 /* Send a request to remove all identities. */ 119 static int 120 delete_all(AuthenticationConnection *ac) 121 { 122 int ret = -1; 123 124 if (ssh_remove_all_identities(ac, 1)) 125 ret = 0; 126 /* ignore error-code for ssh2 */ 127 ssh_remove_all_identities(ac, 2); 128 129 if (ret == 0) 130 fprintf(stderr, "All identities removed.\n"); 131 else 132 fprintf(stderr, "Failed to remove all identities.\n"); 133 134 return ret; 135 } 136 137 static int 138 add_file(AuthenticationConnection *ac, const char *filename) 139 { 140 Key *private; 141 char *comment = NULL; 142 char msg[1024]; 143 int fd, perms_ok, ret = -1; 144 145 if ((fd = open(filename, O_RDONLY)) < 0) { 146 perror(filename); 147 return -1; 148 } 149 150 /* 151 * Since we'll try to load a keyfile multiple times, permission errors 152 * will occur multiple times, so check perms first and bail if wrong. 153 */ 154 perms_ok = key_perm_ok(fd, filename); 155 close(fd); 156 if (!perms_ok) 157 return -1; 158 159 /* At first, try empty passphrase */ 160 private = key_load_private(filename, "", &comment); 161 if (comment == NULL) 162 comment = xstrdup(filename); 163 /* try last */ 164 if (private == NULL && pass != NULL) 165 private = key_load_private(filename, pass, NULL); 166 if (private == NULL) { 167 /* clear passphrase since it did not work */ 168 clear_pass(); 169 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 170 comment); 171 for (;;) { 172 pass = read_passphrase(msg, RP_ALLOW_STDIN); 173 if (strcmp(pass, "") == 0) { 174 clear_pass(); 175 xfree(comment); 176 return -1; 177 } 178 private = key_load_private(filename, pass, &comment); 179 if (private != NULL) 180 break; 181 clear_pass(); 182 snprintf(msg, sizeof msg, 183 "Bad passphrase, try again for %.200s: ", comment); 184 } 185 } 186 187 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 188 confirm)) { 189 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 190 ret = 0; 191 if (lifetime != 0) 192 fprintf(stderr, 193 "Lifetime set to %d seconds\n", lifetime); 194 if (confirm != 0) 195 fprintf(stderr, 196 "The user has to confirm each use of the key\n"); 197 } else if (ssh_add_identity(ac, private, comment)) { 198 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 199 ret = 0; 200 } else { 201 fprintf(stderr, "Could not add identity: %s\n", filename); 202 } 203 204 xfree(comment); 205 key_free(private); 206 207 return ret; 208 } 209 210 static int 211 update_card(AuthenticationConnection *ac, int add, const char *id) 212 { 213 char *pin; 214 int ret = -1; 215 216 pin = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN); 217 if (pin == NULL) 218 return -1; 219 220 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 221 fprintf(stderr, "Card %s: %s\n", 222 add ? "added" : "removed", id); 223 ret = 0; 224 } else { 225 fprintf(stderr, "Could not %s card: %s\n", 226 add ? "add" : "remove", id); 227 ret = -1; 228 } 229 xfree(pin); 230 return ret; 231 } 232 233 static int 234 list_identities(AuthenticationConnection *ac, int do_fp) 235 { 236 Key *key; 237 char *comment, *fp; 238 int had_identities = 0; 239 int version; 240 241 for (version = 1; version <= 2; version++) { 242 for (key = ssh_get_first_identity(ac, &comment, version); 243 key != NULL; 244 key = ssh_get_next_identity(ac, &comment, version)) { 245 had_identities = 1; 246 if (do_fp) { 247 fp = key_fingerprint(key, SSH_FP_MD5, 248 SSH_FP_HEX); 249 printf("%d %s %s (%s)\n", 250 key_size(key), fp, comment, key_type(key)); 251 xfree(fp); 252 } else { 253 if (!key_write(key, stdout)) 254 fprintf(stderr, "key_write failed"); 255 fprintf(stdout, " %s\n", comment); 256 } 257 key_free(key); 258 xfree(comment); 259 } 260 } 261 if (!had_identities) { 262 printf("The agent has no identities.\n"); 263 return -1; 264 } 265 return 0; 266 } 267 268 static int 269 lock_agent(AuthenticationConnection *ac, int lock) 270 { 271 char prompt[100], *p1, *p2; 272 int passok = 1, ret = -1; 273 274 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 275 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 276 if (lock) { 277 strlcpy(prompt, "Again: ", sizeof prompt); 278 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 279 if (strcmp(p1, p2) != 0) { 280 fprintf(stderr, "Passwords do not match.\n"); 281 passok = 0; 282 } 283 memset(p2, 0, strlen(p2)); 284 xfree(p2); 285 } 286 if (passok && ssh_lock_agent(ac, lock, p1)) { 287 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 288 ret = 0; 289 } else 290 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 291 memset(p1, 0, strlen(p1)); 292 xfree(p1); 293 return (ret); 294 } 295 296 static int 297 do_file(AuthenticationConnection *ac, int deleting, char *file) 298 { 299 if (deleting) { 300 if (delete_file(ac, file) == -1) 301 return -1; 302 } else { 303 if (add_file(ac, file) == -1) 304 return -1; 305 } 306 return 0; 307 } 308 309 static void 310 usage(void) 311 { 312 fprintf(stderr, "Usage: %s [options] [file ...]\n", __progname); 313 fprintf(stderr, "Options:\n"); 314 fprintf(stderr, " -l List fingerprints of all identities.\n"); 315 fprintf(stderr, " -L List public key parameters of all identities.\n"); 316 fprintf(stderr, " -d Delete identity.\n"); 317 fprintf(stderr, " -D Delete all identities.\n"); 318 fprintf(stderr, " -x Lock agent.\n"); 319 fprintf(stderr, " -X Unlock agent.\n"); 320 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 321 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 322 #ifdef SMARTCARD 323 fprintf(stderr, " -s reader Add key in smartcard reader.\n"); 324 fprintf(stderr, " -e reader Remove key in smartcard reader.\n"); 325 #endif 326 } 327 328 int 329 main(int argc, char **argv) 330 { 331 extern char *optarg; 332 extern int optind; 333 AuthenticationConnection *ac = NULL; 334 char *sc_reader_id = NULL; 335 int i, ch, deleting = 0, ret = 0; 336 337 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 338 sanitise_stdfd(); 339 340 __progname = ssh_get_progname(argv[0]); 341 init_rng(); 342 seed_rng(); 343 344 SSLeay_add_all_algorithms(); 345 346 /* At first, get a connection to the authentication agent. */ 347 ac = ssh_get_authentication_connection(); 348 if (ac == NULL) { 349 fprintf(stderr, 350 "Could not open a connection to your authentication agent.\n"); 351 exit(2); 352 } 353 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 354 switch (ch) { 355 case 'l': 356 case 'L': 357 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 358 ret = 1; 359 goto done; 360 case 'x': 361 case 'X': 362 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 363 ret = 1; 364 goto done; 365 case 'c': 366 confirm = 1; 367 break; 368 case 'd': 369 deleting = 1; 370 break; 371 case 'D': 372 if (delete_all(ac) == -1) 373 ret = 1; 374 goto done; 375 case 's': 376 sc_reader_id = optarg; 377 break; 378 case 'e': 379 deleting = 1; 380 sc_reader_id = optarg; 381 break; 382 case 't': 383 if ((lifetime = convtime(optarg)) == -1) { 384 fprintf(stderr, "Invalid lifetime\n"); 385 ret = 1; 386 goto done; 387 } 388 break; 389 default: 390 usage(); 391 ret = 1; 392 goto done; 393 } 394 } 395 argc -= optind; 396 argv += optind; 397 if (sc_reader_id != NULL) { 398 if (update_card(ac, !deleting, sc_reader_id) == -1) 399 ret = 1; 400 goto done; 401 } 402 if (argc == 0) { 403 char buf[MAXPATHLEN]; 404 struct passwd *pw; 405 struct stat st; 406 int count = 0; 407 408 if ((pw = getpwuid(getuid())) == NULL) { 409 fprintf(stderr, "No user found with uid %u\n", 410 (u_int)getuid()); 411 ret = 1; 412 goto done; 413 } 414 415 for (i = 0; default_files[i]; i++) { 416 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 417 default_files[i]); 418 if (stat(buf, &st) < 0) 419 continue; 420 if (do_file(ac, deleting, buf) == -1) 421 ret = 1; 422 else 423 count++; 424 } 425 if (count == 0) 426 ret = 1; 427 } else { 428 for (i = 0; i < argc; i++) { 429 if (do_file(ac, deleting, argv[i]) == -1) 430 ret = 1; 431 } 432 } 433 clear_pass(); 434 435 done: 436 ssh_close_authentication_connection(ac); 437 return ret; 438 } 439