1 /* $OpenBSD: ssh-add.c,v 1.90 2007/09/09 11:38:01 sobrado 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 #include "openbsd-compat/openssl-compat.h" 46 47 #include <fcntl.h> 48 #include <pwd.h> 49 #include <stdarg.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <unistd.h> 54 55 #include "xmalloc.h" 56 #include "ssh.h" 57 #include "rsa.h" 58 #include "log.h" 59 #include "key.h" 60 #include "buffer.h" 61 #include "authfd.h" 62 #include "authfile.h" 63 #include "pathnames.h" 64 #include "misc.h" 65 66 /* argv0 */ 67 extern char *__progname; 68 69 /* Default files to add */ 70 static char *default_files[] = { 71 _PATH_SSH_CLIENT_ID_RSA, 72 _PATH_SSH_CLIENT_ID_DSA, 73 _PATH_SSH_CLIENT_IDENTITY, 74 NULL 75 }; 76 77 /* Default lifetime (0 == forever) */ 78 static int lifetime = 0; 79 80 /* User has to confirm key use */ 81 static int confirm = 0; 82 83 /* we keep a cache of one passphrases */ 84 static char *pass = NULL; 85 static void 86 clear_pass(void) 87 { 88 if (pass) { 89 memset(pass, 0, strlen(pass)); 90 xfree(pass); 91 pass = NULL; 92 } 93 } 94 95 static int 96 delete_file(AuthenticationConnection *ac, const char *filename) 97 { 98 Key *public; 99 char *comment = NULL; 100 int ret = -1; 101 102 public = key_load_public(filename, &comment); 103 if (public == NULL) { 104 printf("Bad key file %s\n", filename); 105 return -1; 106 } 107 if (ssh_remove_identity(ac, public)) { 108 fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment); 109 ret = 0; 110 } else 111 fprintf(stderr, "Could not remove identity: %s\n", filename); 112 113 key_free(public); 114 xfree(comment); 115 116 return ret; 117 } 118 119 /* Send a request to remove all identities. */ 120 static int 121 delete_all(AuthenticationConnection *ac) 122 { 123 int ret = -1; 124 125 if (ssh_remove_all_identities(ac, 1)) 126 ret = 0; 127 /* ignore error-code for ssh2 */ 128 ssh_remove_all_identities(ac, 2); 129 130 if (ret == 0) 131 fprintf(stderr, "All identities removed.\n"); 132 else 133 fprintf(stderr, "Failed to remove all identities.\n"); 134 135 return ret; 136 } 137 138 static int 139 add_file(AuthenticationConnection *ac, const char *filename) 140 { 141 Key *private; 142 char *comment = NULL; 143 char msg[1024]; 144 int fd, perms_ok, ret = -1; 145 146 if ((fd = open(filename, O_RDONLY)) < 0) { 147 perror(filename); 148 return -1; 149 } 150 151 /* 152 * Since we'll try to load a keyfile multiple times, permission errors 153 * will occur multiple times, so check perms first and bail if wrong. 154 */ 155 perms_ok = key_perm_ok(fd, filename); 156 close(fd); 157 if (!perms_ok) 158 return -1; 159 160 /* At first, try empty passphrase */ 161 private = key_load_private(filename, "", &comment); 162 if (comment == NULL) 163 comment = xstrdup(filename); 164 /* try last */ 165 if (private == NULL && pass != NULL) 166 private = key_load_private(filename, pass, NULL); 167 if (private == NULL) { 168 /* clear passphrase since it did not work */ 169 clear_pass(); 170 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 171 comment); 172 for (;;) { 173 pass = read_passphrase(msg, RP_ALLOW_STDIN); 174 if (strcmp(pass, "") == 0) { 175 clear_pass(); 176 xfree(comment); 177 return -1; 178 } 179 private = key_load_private(filename, pass, &comment); 180 if (private != NULL) 181 break; 182 clear_pass(); 183 snprintf(msg, sizeof msg, 184 "Bad passphrase, try again for %.200s: ", comment); 185 } 186 } 187 188 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 189 confirm)) { 190 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 191 ret = 0; 192 if (lifetime != 0) 193 fprintf(stderr, 194 "Lifetime set to %d seconds\n", lifetime); 195 if (confirm != 0) 196 fprintf(stderr, 197 "The user has to confirm each use of the key\n"); 198 } else if (ssh_add_identity(ac, private, comment)) { 199 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 200 ret = 0; 201 } else { 202 fprintf(stderr, "Could not add identity: %s\n", filename); 203 } 204 205 xfree(comment); 206 key_free(private); 207 208 return ret; 209 } 210 211 static int 212 update_card(AuthenticationConnection *ac, int add, const char *id) 213 { 214 char *pin; 215 int ret = -1; 216 217 pin = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN); 218 if (pin == NULL) 219 return -1; 220 221 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 222 fprintf(stderr, "Card %s: %s\n", 223 add ? "added" : "removed", id); 224 ret = 0; 225 } else { 226 fprintf(stderr, "Could not %s card: %s\n", 227 add ? "add" : "remove", id); 228 ret = -1; 229 } 230 xfree(pin); 231 return ret; 232 } 233 234 static int 235 list_identities(AuthenticationConnection *ac, int do_fp) 236 { 237 Key *key; 238 char *comment, *fp; 239 int had_identities = 0; 240 int version; 241 242 for (version = 1; version <= 2; version++) { 243 for (key = ssh_get_first_identity(ac, &comment, version); 244 key != NULL; 245 key = ssh_get_next_identity(ac, &comment, version)) { 246 had_identities = 1; 247 if (do_fp) { 248 fp = key_fingerprint(key, SSH_FP_MD5, 249 SSH_FP_HEX); 250 printf("%d %s %s (%s)\n", 251 key_size(key), fp, comment, key_type(key)); 252 xfree(fp); 253 } else { 254 if (!key_write(key, stdout)) 255 fprintf(stderr, "key_write failed"); 256 fprintf(stdout, " %s\n", comment); 257 } 258 key_free(key); 259 xfree(comment); 260 } 261 } 262 if (!had_identities) { 263 printf("The agent has no identities.\n"); 264 return -1; 265 } 266 return 0; 267 } 268 269 static int 270 lock_agent(AuthenticationConnection *ac, int lock) 271 { 272 char prompt[100], *p1, *p2; 273 int passok = 1, ret = -1; 274 275 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 276 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 277 if (lock) { 278 strlcpy(prompt, "Again: ", sizeof prompt); 279 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 280 if (strcmp(p1, p2) != 0) { 281 fprintf(stderr, "Passwords do not match.\n"); 282 passok = 0; 283 } 284 memset(p2, 0, strlen(p2)); 285 xfree(p2); 286 } 287 if (passok && ssh_lock_agent(ac, lock, p1)) { 288 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 289 ret = 0; 290 } else 291 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 292 memset(p1, 0, strlen(p1)); 293 xfree(p1); 294 return (ret); 295 } 296 297 static int 298 do_file(AuthenticationConnection *ac, int deleting, char *file) 299 { 300 if (deleting) { 301 if (delete_file(ac, file) == -1) 302 return -1; 303 } else { 304 if (add_file(ac, file) == -1) 305 return -1; 306 } 307 return 0; 308 } 309 310 static void 311 usage(void) 312 { 313 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 314 fprintf(stderr, "Options:\n"); 315 fprintf(stderr, " -l List fingerprints of all identities.\n"); 316 fprintf(stderr, " -L List public key parameters of all identities.\n"); 317 fprintf(stderr, " -d Delete identity.\n"); 318 fprintf(stderr, " -D Delete all identities.\n"); 319 fprintf(stderr, " -x Lock agent.\n"); 320 fprintf(stderr, " -X Unlock agent.\n"); 321 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 322 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 323 #ifdef SMARTCARD 324 fprintf(stderr, " -s reader Add key in smartcard reader.\n"); 325 fprintf(stderr, " -e reader Remove key in smartcard reader.\n"); 326 #endif 327 } 328 329 int 330 main(int argc, char **argv) 331 { 332 extern char *optarg; 333 extern int optind; 334 AuthenticationConnection *ac = NULL; 335 char *sc_reader_id = NULL; 336 int i, ch, deleting = 0, ret = 0; 337 338 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 339 sanitise_stdfd(); 340 341 __progname = ssh_get_progname(argv[0]); 342 init_rng(); 343 seed_rng(); 344 345 SSLeay_add_all_algorithms(); 346 347 /* At first, get a connection to the authentication agent. */ 348 ac = ssh_get_authentication_connection(); 349 if (ac == NULL) { 350 fprintf(stderr, 351 "Could not open a connection to your authentication agent.\n"); 352 exit(2); 353 } 354 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 355 switch (ch) { 356 case 'l': 357 case 'L': 358 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 359 ret = 1; 360 goto done; 361 case 'x': 362 case 'X': 363 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 364 ret = 1; 365 goto done; 366 case 'c': 367 confirm = 1; 368 break; 369 case 'd': 370 deleting = 1; 371 break; 372 case 'D': 373 if (delete_all(ac) == -1) 374 ret = 1; 375 goto done; 376 case 's': 377 sc_reader_id = optarg; 378 break; 379 case 'e': 380 deleting = 1; 381 sc_reader_id = optarg; 382 break; 383 case 't': 384 if ((lifetime = convtime(optarg)) == -1) { 385 fprintf(stderr, "Invalid lifetime\n"); 386 ret = 1; 387 goto done; 388 } 389 break; 390 default: 391 usage(); 392 ret = 1; 393 goto done; 394 } 395 } 396 argc -= optind; 397 argv += optind; 398 if (sc_reader_id != NULL) { 399 if (update_card(ac, !deleting, sc_reader_id) == -1) 400 ret = 1; 401 goto done; 402 } 403 if (argc == 0) { 404 char buf[MAXPATHLEN]; 405 struct passwd *pw; 406 struct stat st; 407 int count = 0; 408 409 if ((pw = getpwuid(getuid())) == NULL) { 410 fprintf(stderr, "No user found with uid %u\n", 411 (u_int)getuid()); 412 ret = 1; 413 goto done; 414 } 415 416 for (i = 0; default_files[i]; i++) { 417 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 418 default_files[i]); 419 if (stat(buf, &st) < 0) 420 continue; 421 if (do_file(ac, deleting, buf) == -1) 422 ret = 1; 423 else 424 count++; 425 } 426 if (count == 0) 427 ret = 1; 428 } else { 429 for (i = 0; i < argc; i++) { 430 if (do_file(ac, deleting, argv[i]) == -1) 431 ret = 1; 432 } 433 } 434 clear_pass(); 435 436 done: 437 ssh_close_authentication_connection(ac); 438 return ret; 439 } 440