1 /* $OpenBSD: ssh-add.c,v 1.96 2010/05/14 00:47:22 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 _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, *cert; 142 char *comment = NULL; 143 char msg[1024], *certpath; 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 must confirm each use of the key\n"); 198 } else { 199 fprintf(stderr, "Could not add identity: %s\n", filename); 200 } 201 202 203 /* Now try to add the certificate flavour too */ 204 xasprintf(&certpath, "%s-cert.pub", filename); 205 if ((cert = key_load_public(certpath, NULL)) == NULL) 206 goto out; 207 208 if (!key_equal_public(cert, private)) { 209 error("Certificate %s does not match private key %s", 210 certpath, filename); 211 key_free(cert); 212 goto out; 213 } 214 215 /* Graft with private bits */ 216 if (key_to_certified(private, key_cert_is_legacy(cert)) != 0) { 217 error("%s: key_to_certified failed", __func__); 218 key_free(cert); 219 goto out; 220 } 221 key_cert_copy(cert, private); 222 key_free(cert); 223 224 if (!ssh_add_identity_constrained(ac, private, comment, 225 lifetime, confirm)) { 226 error("Certificate %s (%s) add failed", certpath, 227 private->cert->key_id); 228 } 229 fprintf(stderr, "Certificate added: %s (%s)\n", certpath, 230 private->cert->key_id); 231 if (lifetime != 0) 232 fprintf(stderr, "Lifetime set to %d seconds\n", lifetime); 233 if (confirm != 0) 234 fprintf(stderr, "The user must confirm each use of the key\n"); 235 out: 236 xfree(certpath); 237 xfree(comment); 238 key_free(private); 239 240 return ret; 241 } 242 243 static int 244 update_card(AuthenticationConnection *ac, int add, const char *id) 245 { 246 char *pin; 247 int ret = -1; 248 249 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 250 if (pin == NULL) 251 return -1; 252 253 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 254 fprintf(stderr, "Card %s: %s\n", 255 add ? "added" : "removed", id); 256 ret = 0; 257 } else { 258 fprintf(stderr, "Could not %s card: %s\n", 259 add ? "add" : "remove", id); 260 ret = -1; 261 } 262 xfree(pin); 263 return ret; 264 } 265 266 static int 267 list_identities(AuthenticationConnection *ac, int do_fp) 268 { 269 Key *key; 270 char *comment, *fp; 271 int had_identities = 0; 272 int version; 273 274 for (version = 1; version <= 2; version++) { 275 for (key = ssh_get_first_identity(ac, &comment, version); 276 key != NULL; 277 key = ssh_get_next_identity(ac, &comment, version)) { 278 had_identities = 1; 279 if (do_fp) { 280 fp = key_fingerprint(key, SSH_FP_MD5, 281 SSH_FP_HEX); 282 printf("%d %s %s (%s)\n", 283 key_size(key), fp, comment, key_type(key)); 284 xfree(fp); 285 } else { 286 if (!key_write(key, stdout)) 287 fprintf(stderr, "key_write failed"); 288 fprintf(stdout, " %s\n", comment); 289 } 290 key_free(key); 291 xfree(comment); 292 } 293 } 294 if (!had_identities) { 295 printf("The agent has no identities.\n"); 296 return -1; 297 } 298 return 0; 299 } 300 301 static int 302 lock_agent(AuthenticationConnection *ac, int lock) 303 { 304 char prompt[100], *p1, *p2; 305 int passok = 1, ret = -1; 306 307 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 308 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 309 if (lock) { 310 strlcpy(prompt, "Again: ", sizeof prompt); 311 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 312 if (strcmp(p1, p2) != 0) { 313 fprintf(stderr, "Passwords do not match.\n"); 314 passok = 0; 315 } 316 memset(p2, 0, strlen(p2)); 317 xfree(p2); 318 } 319 if (passok && ssh_lock_agent(ac, lock, p1)) { 320 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 321 ret = 0; 322 } else 323 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 324 memset(p1, 0, strlen(p1)); 325 xfree(p1); 326 return (ret); 327 } 328 329 static int 330 do_file(AuthenticationConnection *ac, int deleting, char *file) 331 { 332 if (deleting) { 333 if (delete_file(ac, file) == -1) 334 return -1; 335 } else { 336 if (add_file(ac, file) == -1) 337 return -1; 338 } 339 return 0; 340 } 341 342 static void 343 usage(void) 344 { 345 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 346 fprintf(stderr, "Options:\n"); 347 fprintf(stderr, " -l List fingerprints of all identities.\n"); 348 fprintf(stderr, " -L List public key parameters of all identities.\n"); 349 fprintf(stderr, " -d Delete identity.\n"); 350 fprintf(stderr, " -D Delete all identities.\n"); 351 fprintf(stderr, " -x Lock agent.\n"); 352 fprintf(stderr, " -X Unlock agent.\n"); 353 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 354 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 355 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 356 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 357 } 358 359 int 360 main(int argc, char **argv) 361 { 362 extern char *optarg; 363 extern int optind; 364 AuthenticationConnection *ac = NULL; 365 char *pkcs11provider = NULL; 366 int i, ch, deleting = 0, ret = 0; 367 368 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 369 sanitise_stdfd(); 370 371 __progname = ssh_get_progname(argv[0]); 372 init_rng(); 373 seed_rng(); 374 375 SSLeay_add_all_algorithms(); 376 377 /* At first, get a connection to the authentication agent. */ 378 ac = ssh_get_authentication_connection(); 379 if (ac == NULL) { 380 fprintf(stderr, 381 "Could not open a connection to your authentication agent.\n"); 382 exit(2); 383 } 384 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 385 switch (ch) { 386 case 'l': 387 case 'L': 388 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 389 ret = 1; 390 goto done; 391 case 'x': 392 case 'X': 393 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 394 ret = 1; 395 goto done; 396 case 'c': 397 confirm = 1; 398 break; 399 case 'd': 400 deleting = 1; 401 break; 402 case 'D': 403 if (delete_all(ac) == -1) 404 ret = 1; 405 goto done; 406 case 's': 407 pkcs11provider = optarg; 408 break; 409 case 'e': 410 deleting = 1; 411 pkcs11provider = optarg; 412 break; 413 case 't': 414 if ((lifetime = convtime(optarg)) == -1) { 415 fprintf(stderr, "Invalid lifetime\n"); 416 ret = 1; 417 goto done; 418 } 419 break; 420 default: 421 usage(); 422 ret = 1; 423 goto done; 424 } 425 } 426 argc -= optind; 427 argv += optind; 428 if (pkcs11provider != NULL) { 429 if (update_card(ac, !deleting, pkcs11provider) == -1) 430 ret = 1; 431 goto done; 432 } 433 if (argc == 0) { 434 char buf[MAXPATHLEN]; 435 struct passwd *pw; 436 struct stat st; 437 int count = 0; 438 439 if ((pw = getpwuid(getuid())) == NULL) { 440 fprintf(stderr, "No user found with uid %u\n", 441 (u_int)getuid()); 442 ret = 1; 443 goto done; 444 } 445 446 for (i = 0; default_files[i]; i++) { 447 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 448 default_files[i]); 449 if (stat(buf, &st) < 0) 450 continue; 451 if (do_file(ac, deleting, buf) == -1) 452 ret = 1; 453 else 454 count++; 455 } 456 if (count == 0) 457 ret = 1; 458 } else { 459 for (i = 0; i < argc; i++) { 460 if (do_file(ac, deleting, argv[i]) == -1) 461 ret = 1; 462 } 463 } 464 clear_pass(); 465 466 done: 467 ssh_close_authentication_connection(ac); 468 return ret; 469 } 470