1 /* $OpenBSD: ssh-add.c,v 1.101 2011/05/04 21:15:29 djm Exp $ */ 2 /* 3 * Author: Tatu Ylonen <ylo (at) cs.hut.fi> 4 * Copyright (c) 1995 Tatu Ylonen <ylo (at) 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 #ifdef OPENSSL_HAS_ECC 74 _PATH_SSH_CLIENT_ID_ECDSA, 75 #endif 76 _PATH_SSH_CLIENT_IDENTITY, 77 NULL 78 }; 79 80 /* Default lifetime (0 == forever) */ 81 static int lifetime = 0; 82 83 /* User has to confirm key use */ 84 static int confirm = 0; 85 86 /* we keep a cache of one passphrases */ 87 static char *pass = NULL; 88 static void 89 clear_pass(void) 90 { 91 if (pass) { 92 memset(pass, 0, strlen(pass)); 93 xfree(pass); 94 pass = NULL; 95 } 96 } 97 98 static int 99 delete_file(AuthenticationConnection *ac, const char *filename) 100 { 101 Key *public; 102 char *comment = NULL; 103 int ret = -1; 104 105 public = key_load_public(filename, &comment); 106 if (public == NULL) { 107 printf("Bad key file %s\n", filename); 108 return -1; 109 } 110 if (ssh_remove_identity(ac, public)) { 111 fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment); 112 ret = 0; 113 } else 114 fprintf(stderr, "Could not remove identity: %s\n", filename); 115 116 key_free(public); 117 xfree(comment); 118 119 return ret; 120 } 121 122 /* Send a request to remove all identities. */ 123 static int 124 delete_all(AuthenticationConnection *ac) 125 { 126 int ret = -1; 127 128 if (ssh_remove_all_identities(ac, 1)) 129 ret = 0; 130 /* ignore error-code for ssh2 */ 131 ssh_remove_all_identities(ac, 2); 132 133 if (ret == 0) 134 fprintf(stderr, "All identities removed.\n"); 135 else 136 fprintf(stderr, "Failed to remove all identities.\n"); 137 138 return ret; 139 } 140 141 static int 142 add_file(AuthenticationConnection *ac, const char *filename) 143 { 144 Key *private, *cert; 145 char *comment = NULL; 146 char msg[1024], *certpath; 147 int fd, perms_ok, ret = -1; 148 Buffer keyblob; 149 150 if (strcmp(filename, "-") == 0) { 151 fd = STDIN_FILENO; 152 filename = "(stdin)"; 153 } else if ((fd = open(filename, O_RDONLY)) < 0) { 154 perror(filename); 155 return -1; 156 } 157 158 /* 159 * Since we'll try to load a keyfile multiple times, permission errors 160 * will occur multiple times, so check perms first and bail if wrong. 161 */ 162 if (fd != STDIN_FILENO) { 163 perms_ok = key_perm_ok(fd, filename); 164 if (!perms_ok) { 165 close(fd); 166 return -1; 167 } 168 } 169 buffer_init(&keyblob); 170 if (!key_load_file(fd, filename, &keyblob)) { 171 buffer_free(&keyblob); 172 close(fd); 173 return -1; 174 } 175 close(fd); 176 177 /* At first, try empty passphrase */ 178 private = key_parse_private(&keyblob, filename, "", &comment); 179 if (comment == NULL) 180 comment = xstrdup(filename); 181 /* try last */ 182 if (private == NULL && pass != NULL) 183 private = key_parse_private(&keyblob, filename, pass, NULL); 184 if (private == NULL) { 185 /* clear passphrase since it did not work */ 186 clear_pass(); 187 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 188 comment); 189 for (;;) { 190 pass = read_passphrase(msg, RP_ALLOW_STDIN); 191 if (strcmp(pass, "") == 0) { 192 clear_pass(); 193 xfree(comment); 194 buffer_free(&keyblob); 195 return -1; 196 } 197 private = key_parse_private(&keyblob, filename, pass, 198 &comment); 199 if (private != NULL) 200 break; 201 clear_pass(); 202 snprintf(msg, sizeof msg, 203 "Bad passphrase, try again for %.200s: ", comment); 204 } 205 } 206 buffer_free(&keyblob); 207 208 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 209 confirm)) { 210 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 211 ret = 0; 212 if (lifetime != 0) 213 fprintf(stderr, 214 "Lifetime set to %d seconds\n", lifetime); 215 if (confirm != 0) 216 fprintf(stderr, 217 "The user must confirm each use of the key\n"); 218 } else { 219 fprintf(stderr, "Could not add identity: %s\n", filename); 220 } 221 222 223 /* Now try to add the certificate flavour too */ 224 xasprintf(&certpath, "%s-cert.pub", filename); 225 if ((cert = key_load_public(certpath, NULL)) == NULL) 226 goto out; 227 228 if (!key_equal_public(cert, private)) { 229 error("Certificate %s does not match private key %s", 230 certpath, filename); 231 key_free(cert); 232 goto out; 233 } 234 235 /* Graft with private bits */ 236 if (key_to_certified(private, key_cert_is_legacy(cert)) != 0) { 237 error("%s: key_to_certified failed", __func__); 238 key_free(cert); 239 goto out; 240 } 241 key_cert_copy(cert, private); 242 key_free(cert); 243 244 if (!ssh_add_identity_constrained(ac, private, comment, 245 lifetime, confirm)) { 246 error("Certificate %s (%s) add failed", certpath, 247 private->cert->key_id); 248 } 249 fprintf(stderr, "Certificate added: %s (%s)\n", certpath, 250 private->cert->key_id); 251 if (lifetime != 0) 252 fprintf(stderr, "Lifetime set to %d seconds\n", lifetime); 253 if (confirm != 0) 254 fprintf(stderr, "The user must confirm each use of the key\n"); 255 out: 256 xfree(certpath); 257 xfree(comment); 258 key_free(private); 259 260 return ret; 261 } 262 263 static int 264 update_card(AuthenticationConnection *ac, int add, const char *id) 265 { 266 char *pin; 267 int ret = -1; 268 269 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 270 if (pin == NULL) 271 return -1; 272 273 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 274 fprintf(stderr, "Card %s: %s\n", 275 add ? "added" : "removed", id); 276 ret = 0; 277 } else { 278 fprintf(stderr, "Could not %s card: %s\n", 279 add ? "add" : "remove", id); 280 ret = -1; 281 } 282 xfree(pin); 283 return ret; 284 } 285 286 static int 287 list_identities(AuthenticationConnection *ac, int do_fp) 288 { 289 Key *key; 290 char *comment, *fp; 291 int had_identities = 0; 292 int version; 293 294 for (version = 1; version <= 2; version++) { 295 for (key = ssh_get_first_identity(ac, &comment, version); 296 key != NULL; 297 key = ssh_get_next_identity(ac, &comment, version)) { 298 had_identities = 1; 299 if (do_fp) { 300 fp = key_fingerprint(key, SSH_FP_MD5, 301 SSH_FP_HEX); 302 printf("%d %s %s (%s)\n", 303 key_size(key), fp, comment, key_type(key)); 304 xfree(fp); 305 } else { 306 if (!key_write(key, stdout)) 307 fprintf(stderr, "key_write failed"); 308 fprintf(stdout, " %s\n", comment); 309 } 310 key_free(key); 311 xfree(comment); 312 } 313 } 314 if (!had_identities) { 315 printf("The agent has no identities.\n"); 316 return -1; 317 } 318 return 0; 319 } 320 321 static int 322 lock_agent(AuthenticationConnection *ac, int lock) 323 { 324 char prompt[100], *p1, *p2; 325 int passok = 1, ret = -1; 326 327 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 328 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 329 if (lock) { 330 strlcpy(prompt, "Again: ", sizeof prompt); 331 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 332 if (strcmp(p1, p2) != 0) { 333 fprintf(stderr, "Passwords do not match.\n"); 334 passok = 0; 335 } 336 memset(p2, 0, strlen(p2)); 337 xfree(p2); 338 } 339 if (passok && ssh_lock_agent(ac, lock, p1)) { 340 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 341 ret = 0; 342 } else 343 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 344 memset(p1, 0, strlen(p1)); 345 xfree(p1); 346 return (ret); 347 } 348 349 static int 350 do_file(AuthenticationConnection *ac, int deleting, char *file) 351 { 352 if (deleting) { 353 if (delete_file(ac, file) == -1) 354 return -1; 355 } else { 356 if (add_file(ac, file) == -1) 357 return -1; 358 } 359 return 0; 360 } 361 362 static void 363 usage(void) 364 { 365 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 366 fprintf(stderr, "Options:\n"); 367 fprintf(stderr, " -l List fingerprints of all identities.\n"); 368 fprintf(stderr, " -L List public key parameters of all identities.\n"); 369 fprintf(stderr, " -d Delete identity.\n"); 370 fprintf(stderr, " -D Delete all identities.\n"); 371 fprintf(stderr, " -x Lock agent.\n"); 372 fprintf(stderr, " -X Unlock agent.\n"); 373 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 374 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 375 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 376 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 377 } 378 379 int 380 main(int argc, char **argv) 381 { 382 extern char *optarg; 383 extern int optind; 384 AuthenticationConnection *ac = NULL; 385 char *pkcs11provider = NULL; 386 int i, ch, deleting = 0, ret = 0; 387 388 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 389 sanitise_stdfd(); 390 391 __progname = ssh_get_progname(argv[0]); 392 seed_rng(); 393 394 OpenSSL_add_all_algorithms(); 395 396 /* At first, get a connection to the authentication agent. */ 397 ac = ssh_get_authentication_connection(); 398 if (ac == NULL) { 399 fprintf(stderr, 400 "Could not open a connection to your authentication agent.\n"); 401 exit(2); 402 } 403 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 404 switch (ch) { 405 case 'l': 406 case 'L': 407 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 408 ret = 1; 409 goto done; 410 case 'x': 411 case 'X': 412 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 413 ret = 1; 414 goto done; 415 case 'c': 416 confirm = 1; 417 break; 418 case 'd': 419 deleting = 1; 420 break; 421 case 'D': 422 if (delete_all(ac) == -1) 423 ret = 1; 424 goto done; 425 case 's': 426 pkcs11provider = optarg; 427 break; 428 case 'e': 429 deleting = 1; 430 pkcs11provider = optarg; 431 break; 432 case 't': 433 if ((lifetime = convtime(optarg)) == -1) { 434 fprintf(stderr, "Invalid lifetime\n"); 435 ret = 1; 436 goto done; 437 } 438 break; 439 default: 440 usage(); 441 ret = 1; 442 goto done; 443 } 444 } 445 argc -= optind; 446 argv += optind; 447 if (pkcs11provider != NULL) { 448 if (update_card(ac, !deleting, pkcs11provider) == -1) 449 ret = 1; 450 goto done; 451 } 452 if (argc == 0) { 453 char buf[MAXPATHLEN]; 454 struct passwd *pw; 455 struct stat st; 456 int count = 0; 457 458 if ((pw = getpwuid(getuid())) == NULL) { 459 fprintf(stderr, "No user found with uid %u\n", 460 (u_int)getuid()); 461 ret = 1; 462 goto done; 463 } 464 465 for (i = 0; default_files[i]; i++) { 466 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 467 default_files[i]); 468 if (stat(buf, &st) < 0) 469 continue; 470 if (do_file(ac, deleting, buf) == -1) 471 ret = 1; 472 else 473 count++; 474 } 475 if (count == 0) 476 ret = 1; 477 } else { 478 for (i = 0; i < argc; i++) { 479 if (do_file(ac, deleting, argv[i]) == -1) 480 ret = 1; 481 } 482 } 483 clear_pass(); 484 485 done: 486 ssh_close_authentication_connection(ac); 487 return ret; 488 } 489
