1 /* $OpenBSD: ssh-add.c,v 1.100 2010/08/31 12:33:38 djm 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 #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; 148 149 if ((fd = open(filename, O_RDONLY)) < 0) { 150 perror(filename); 151 return -1; 152 } 153 154 /* 155 * Since we'll try to load a keyfile multiple times, permission errors 156 * will occur multiple times, so check perms first and bail if wrong. 157 */ 158 perms_ok = key_perm_ok(fd, filename); 159 close(fd); 160 if (!perms_ok) 161 return -1; 162 163 /* At first, try empty passphrase */ 164 private = key_load_private(filename, "", &comment); 165 if (comment == NULL) 166 comment = xstrdup(filename); 167 /* try last */ 168 if (private == NULL && pass != NULL) 169 private = key_load_private(filename, pass, NULL); 170 if (private == NULL) { 171 /* clear passphrase since it did not work */ 172 clear_pass(); 173 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 174 comment); 175 for (;;) { 176 pass = read_passphrase(msg, RP_ALLOW_STDIN); 177 if (strcmp(pass, "") == 0) { 178 clear_pass(); 179 xfree(comment); 180 return -1; 181 } 182 private = key_load_private(filename, pass, &comment); 183 if (private != NULL) 184 break; 185 clear_pass(); 186 snprintf(msg, sizeof msg, 187 "Bad passphrase, try again for %.200s: ", comment); 188 } 189 } 190 191 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 192 confirm)) { 193 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 194 ret = 0; 195 if (lifetime != 0) 196 fprintf(stderr, 197 "Lifetime set to %d seconds\n", lifetime); 198 if (confirm != 0) 199 fprintf(stderr, 200 "The user must confirm each use of the key\n"); 201 } else { 202 fprintf(stderr, "Could not add identity: %s\n", filename); 203 } 204 205 206 /* Now try to add the certificate flavour too */ 207 xasprintf(&certpath, "%s-cert.pub", filename); 208 if ((cert = key_load_public(certpath, NULL)) == NULL) 209 goto out; 210 211 if (!key_equal_public(cert, private)) { 212 error("Certificate %s does not match private key %s", 213 certpath, filename); 214 key_free(cert); 215 goto out; 216 } 217 218 /* Graft with private bits */ 219 if (key_to_certified(private, key_cert_is_legacy(cert)) != 0) { 220 error("%s: key_to_certified failed", __func__); 221 key_free(cert); 222 goto out; 223 } 224 key_cert_copy(cert, private); 225 key_free(cert); 226 227 if (!ssh_add_identity_constrained(ac, private, comment, 228 lifetime, confirm)) { 229 error("Certificate %s (%s) add failed", certpath, 230 private->cert->key_id); 231 } 232 fprintf(stderr, "Certificate added: %s (%s)\n", certpath, 233 private->cert->key_id); 234 if (lifetime != 0) 235 fprintf(stderr, "Lifetime set to %d seconds\n", lifetime); 236 if (confirm != 0) 237 fprintf(stderr, "The user must confirm each use of the key\n"); 238 out: 239 xfree(certpath); 240 xfree(comment); 241 key_free(private); 242 243 return ret; 244 } 245 246 static int 247 update_card(AuthenticationConnection *ac, int add, const char *id) 248 { 249 char *pin; 250 int ret = -1; 251 252 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 253 if (pin == NULL) 254 return -1; 255 256 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 257 fprintf(stderr, "Card %s: %s\n", 258 add ? "added" : "removed", id); 259 ret = 0; 260 } else { 261 fprintf(stderr, "Could not %s card: %s\n", 262 add ? "add" : "remove", id); 263 ret = -1; 264 } 265 xfree(pin); 266 return ret; 267 } 268 269 static int 270 list_identities(AuthenticationConnection *ac, int do_fp) 271 { 272 Key *key; 273 char *comment, *fp; 274 int had_identities = 0; 275 int version; 276 277 for (version = 1; version <= 2; version++) { 278 for (key = ssh_get_first_identity(ac, &comment, version); 279 key != NULL; 280 key = ssh_get_next_identity(ac, &comment, version)) { 281 had_identities = 1; 282 if (do_fp) { 283 fp = key_fingerprint(key, SSH_FP_MD5, 284 SSH_FP_HEX); 285 printf("%d %s %s (%s)\n", 286 key_size(key), fp, comment, key_type(key)); 287 xfree(fp); 288 } else { 289 if (!key_write(key, stdout)) 290 fprintf(stderr, "key_write failed"); 291 fprintf(stdout, " %s\n", comment); 292 } 293 key_free(key); 294 xfree(comment); 295 } 296 } 297 if (!had_identities) { 298 printf("The agent has no identities.\n"); 299 return -1; 300 } 301 return 0; 302 } 303 304 static int 305 lock_agent(AuthenticationConnection *ac, int lock) 306 { 307 char prompt[100], *p1, *p2; 308 int passok = 1, ret = -1; 309 310 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 311 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 312 if (lock) { 313 strlcpy(prompt, "Again: ", sizeof prompt); 314 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 315 if (strcmp(p1, p2) != 0) { 316 fprintf(stderr, "Passwords do not match.\n"); 317 passok = 0; 318 } 319 memset(p2, 0, strlen(p2)); 320 xfree(p2); 321 } 322 if (passok && ssh_lock_agent(ac, lock, p1)) { 323 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 324 ret = 0; 325 } else 326 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 327 memset(p1, 0, strlen(p1)); 328 xfree(p1); 329 return (ret); 330 } 331 332 static int 333 do_file(AuthenticationConnection *ac, int deleting, char *file) 334 { 335 if (deleting) { 336 if (delete_file(ac, file) == -1) 337 return -1; 338 } else { 339 if (add_file(ac, file) == -1) 340 return -1; 341 } 342 return 0; 343 } 344 345 static void 346 usage(void) 347 { 348 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 349 fprintf(stderr, "Options:\n"); 350 fprintf(stderr, " -l List fingerprints of all identities.\n"); 351 fprintf(stderr, " -L List public key parameters of all identities.\n"); 352 fprintf(stderr, " -d Delete identity.\n"); 353 fprintf(stderr, " -D Delete all identities.\n"); 354 fprintf(stderr, " -x Lock agent.\n"); 355 fprintf(stderr, " -X Unlock agent.\n"); 356 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 357 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 358 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 359 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 360 } 361 362 int 363 main(int argc, char **argv) 364 { 365 extern char *optarg; 366 extern int optind; 367 AuthenticationConnection *ac = NULL; 368 char *pkcs11provider = NULL; 369 int i, ch, deleting = 0, ret = 0; 370 371 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 372 sanitise_stdfd(); 373 374 __progname = ssh_get_progname(argv[0]); 375 init_rng(); 376 seed_rng(); 377 378 OpenSSL_add_all_algorithms(); 379 380 /* At first, get a connection to the authentication agent. */ 381 ac = ssh_get_authentication_connection(); 382 if (ac == NULL) { 383 fprintf(stderr, 384 "Could not open a connection to your authentication agent.\n"); 385 exit(2); 386 } 387 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 388 switch (ch) { 389 case 'l': 390 case 'L': 391 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 392 ret = 1; 393 goto done; 394 case 'x': 395 case 'X': 396 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 397 ret = 1; 398 goto done; 399 case 'c': 400 confirm = 1; 401 break; 402 case 'd': 403 deleting = 1; 404 break; 405 case 'D': 406 if (delete_all(ac) == -1) 407 ret = 1; 408 goto done; 409 case 's': 410 pkcs11provider = optarg; 411 break; 412 case 'e': 413 deleting = 1; 414 pkcs11provider = optarg; 415 break; 416 case 't': 417 if ((lifetime = convtime(optarg)) == -1) { 418 fprintf(stderr, "Invalid lifetime\n"); 419 ret = 1; 420 goto done; 421 } 422 break; 423 default: 424 usage(); 425 ret = 1; 426 goto done; 427 } 428 } 429 argc -= optind; 430 argv += optind; 431 if (pkcs11provider != NULL) { 432 if (update_card(ac, !deleting, pkcs11provider) == -1) 433 ret = 1; 434 goto done; 435 } 436 if (argc == 0) { 437 char buf[MAXPATHLEN]; 438 struct passwd *pw; 439 struct stat st; 440 int count = 0; 441 442 if ((pw = getpwuid(getuid())) == NULL) { 443 fprintf(stderr, "No user found with uid %u\n", 444 (u_int)getuid()); 445 ret = 1; 446 goto done; 447 } 448 449 for (i = 0; default_files[i]; i++) { 450 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 451 default_files[i]); 452 if (stat(buf, &st) < 0) 453 continue; 454 if (do_file(ac, deleting, buf) == -1) 455 ret = 1; 456 else 457 count++; 458 } 459 if (count == 0) 460 ret = 1; 461 } else { 462 for (i = 0; i < argc; i++) { 463 if (do_file(ac, deleting, argv[i]) == -1) 464 ret = 1; 465 } 466 } 467 clear_pass(); 468 469 done: 470 ssh_close_authentication_connection(ac); 471 return ret; 472 } 473