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 <sys/types.h> 39 #include <sys/stat.h> 40 #include <sys/param.h> 41 42 #include <openssl/evp.h> 43 44 #include <fcntl.h> 45 #include <pwd.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <unistd.h> 50 51 #include "xmalloc.h" 52 #include "ssh.h" 53 #include "rsa.h" 54 #include "log.h" 55 #include "key.h" 56 #include "buffer.h" 57 #include "authfd.h" 58 #include "authfile.h" 59 #include "pathnames.h" 60 #include "misc.h" 61 62 /* argv0 */ 63 extern char *__progname; 64 65 /* Default files to add */ 66 static char *default_files[] = { 67 _PATH_SSH_CLIENT_ID_RSA, 68 _PATH_SSH_CLIENT_ID_DSA, 69 _PATH_SSH_CLIENT_ID_ECDSA, 70 _PATH_SSH_CLIENT_IDENTITY, 71 NULL 72 }; 73 74 /* Default lifetime (0 == forever) */ 75 static int lifetime = 0; 76 77 /* User has to confirm key use */ 78 static int confirm = 0; 79 80 /* we keep a cache of one passphrases */ 81 static char *pass = NULL; 82 static void 83 clear_pass(void) 84 { 85 if (pass) { 86 memset(pass, 0, strlen(pass)); 87 xfree(pass); 88 pass = NULL; 89 } 90 } 91 92 static int 93 delete_file(AuthenticationConnection *ac, const char *filename) 94 { 95 Key *public; 96 char *comment = NULL; 97 int ret = -1; 98 99 public = key_load_public(filename, &comment); 100 if (public == NULL) { 101 printf("Bad key file %s\n", filename); 102 return -1; 103 } 104 if (ssh_remove_identity(ac, public)) { 105 fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment); 106 ret = 0; 107 } else 108 fprintf(stderr, "Could not remove identity: %s\n", filename); 109 110 key_free(public); 111 xfree(comment); 112 113 return ret; 114 } 115 116 /* Send a request to remove all identities. */ 117 static int 118 delete_all(AuthenticationConnection *ac) 119 { 120 int ret = -1; 121 122 if (ssh_remove_all_identities(ac, 1)) 123 ret = 0; 124 /* ignore error-code for ssh2 */ 125 ssh_remove_all_identities(ac, 2); 126 127 if (ret == 0) 128 fprintf(stderr, "All identities removed.\n"); 129 else 130 fprintf(stderr, "Failed to remove all identities.\n"); 131 132 return ret; 133 } 134 135 static int 136 add_file(AuthenticationConnection *ac, const char *filename) 137 { 138 Key *private, *cert; 139 char *comment = NULL; 140 char msg[1024], *certpath; 141 int fd, perms_ok, ret = -1; 142 143 if ((fd = open(filename, O_RDONLY)) < 0) { 144 perror(filename); 145 return -1; 146 } 147 148 /* 149 * Since we'll try to load a keyfile multiple times, permission errors 150 * will occur multiple times, so check perms first and bail if wrong. 151 */ 152 perms_ok = key_perm_ok(fd, filename); 153 close(fd); 154 if (!perms_ok) 155 return -1; 156 157 /* At first, try empty passphrase */ 158 private = key_load_private(filename, "", &comment); 159 if (comment == NULL) 160 comment = xstrdup(filename); 161 /* try last */ 162 if (private == NULL && pass != NULL) 163 private = key_load_private(filename, pass, NULL); 164 if (private == NULL) { 165 /* clear passphrase since it did not work */ 166 clear_pass(); 167 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 168 comment); 169 for (;;) { 170 pass = read_passphrase(msg, RP_ALLOW_STDIN); 171 if (strcmp(pass, "") == 0) { 172 clear_pass(); 173 xfree(comment); 174 return -1; 175 } 176 private = key_load_private(filename, pass, &comment); 177 if (private != NULL) 178 break; 179 clear_pass(); 180 snprintf(msg, sizeof msg, 181 "Bad passphrase, try again for %.200s: ", comment); 182 } 183 } 184 185 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 186 confirm)) { 187 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 188 ret = 0; 189 if (lifetime != 0) 190 fprintf(stderr, 191 "Lifetime set to %d seconds\n", lifetime); 192 if (confirm != 0) 193 fprintf(stderr, 194 "The user must confirm each use of the key\n"); 195 } else { 196 fprintf(stderr, "Could not add identity: %s\n", filename); 197 } 198 199 200 /* Now try to add the certificate flavour too */ 201 xasprintf(&certpath, "%s-cert.pub", filename); 202 if ((cert = key_load_public(certpath, NULL)) == NULL) 203 goto out; 204 205 if (!key_equal_public(cert, private)) { 206 error("Certificate %s does not match private key %s", 207 certpath, filename); 208 key_free(cert); 209 goto out; 210 } 211 212 /* Graft with private bits */ 213 if (key_to_certified(private, key_cert_is_legacy(cert)) != 0) { 214 error("%s: key_to_certified failed", __func__); 215 key_free(cert); 216 goto out; 217 } 218 key_cert_copy(cert, private); 219 key_free(cert); 220 221 if (!ssh_add_identity_constrained(ac, private, comment, 222 lifetime, confirm)) { 223 error("Certificate %s (%s) add failed", certpath, 224 private->cert->key_id); 225 } 226 fprintf(stderr, "Certificate added: %s (%s)\n", certpath, 227 private->cert->key_id); 228 if (lifetime != 0) 229 fprintf(stderr, "Lifetime set to %d seconds\n", lifetime); 230 if (confirm != 0) 231 fprintf(stderr, "The user must confirm each use of the key\n"); 232 out: 233 xfree(certpath); 234 xfree(comment); 235 key_free(private); 236 237 return ret; 238 } 239 240 static int 241 update_card(AuthenticationConnection *ac, int add, const char *id) 242 { 243 char *pin; 244 int ret = -1; 245 246 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 247 if (pin == NULL) 248 return -1; 249 250 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 251 fprintf(stderr, "Card %s: %s\n", 252 add ? "added" : "removed", id); 253 ret = 0; 254 } else { 255 fprintf(stderr, "Could not %s card: %s\n", 256 add ? "add" : "remove", id); 257 ret = -1; 258 } 259 xfree(pin); 260 return ret; 261 } 262 263 static int 264 list_identities(AuthenticationConnection *ac, int do_fp) 265 { 266 Key *key; 267 char *comment, *fp; 268 int had_identities = 0; 269 int version; 270 271 for (version = 1; version <= 2; version++) { 272 for (key = ssh_get_first_identity(ac, &comment, version); 273 key != NULL; 274 key = ssh_get_next_identity(ac, &comment, version)) { 275 had_identities = 1; 276 if (do_fp) { 277 fp = key_fingerprint(key, SSH_FP_MD5, 278 SSH_FP_HEX); 279 printf("%d %s %s (%s)\n", 280 key_size(key), fp, comment, key_type(key)); 281 xfree(fp); 282 } else { 283 if (!key_write(key, stdout)) 284 fprintf(stderr, "key_write failed"); 285 fprintf(stdout, " %s\n", comment); 286 } 287 key_free(key); 288 xfree(comment); 289 } 290 } 291 if (!had_identities) { 292 printf("The agent has no identities.\n"); 293 return -1; 294 } 295 return 0; 296 } 297 298 static int 299 lock_agent(AuthenticationConnection *ac, int lock) 300 { 301 char prompt[100], *p1, *p2; 302 int passok = 1, ret = -1; 303 304 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 305 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 306 if (lock) { 307 strlcpy(prompt, "Again: ", sizeof prompt); 308 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 309 if (strcmp(p1, p2) != 0) { 310 fprintf(stderr, "Passwords do not match.\n"); 311 passok = 0; 312 } 313 memset(p2, 0, strlen(p2)); 314 xfree(p2); 315 } 316 if (passok && ssh_lock_agent(ac, lock, p1)) { 317 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 318 ret = 0; 319 } else 320 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 321 memset(p1, 0, strlen(p1)); 322 xfree(p1); 323 return (ret); 324 } 325 326 static int 327 do_file(AuthenticationConnection *ac, int deleting, char *file) 328 { 329 if (deleting) { 330 if (delete_file(ac, file) == -1) 331 return -1; 332 } else { 333 if (add_file(ac, file) == -1) 334 return -1; 335 } 336 return 0; 337 } 338 339 static void 340 usage(void) 341 { 342 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 343 fprintf(stderr, "Options:\n"); 344 fprintf(stderr, " -l List fingerprints of all identities.\n"); 345 fprintf(stderr, " -L List public key parameters of all identities.\n"); 346 fprintf(stderr, " -d Delete identity.\n"); 347 fprintf(stderr, " -D Delete all identities.\n"); 348 fprintf(stderr, " -x Lock agent.\n"); 349 fprintf(stderr, " -X Unlock agent.\n"); 350 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 351 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 352 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 353 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 354 } 355 356 int 357 main(int argc, char **argv) 358 { 359 extern char *optarg; 360 extern int optind; 361 AuthenticationConnection *ac = NULL; 362 char *pkcs11provider = NULL; 363 int i, ch, deleting = 0, ret = 0; 364 365 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 366 sanitise_stdfd(); 367 368 OpenSSL_add_all_algorithms(); 369 370 /* At first, get a connection to the authentication agent. */ 371 ac = ssh_get_authentication_connection(); 372 if (ac == NULL) { 373 fprintf(stderr, 374 "Could not open a connection to your authentication agent.\n"); 375 exit(2); 376 } 377 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 378 switch (ch) { 379 case 'l': 380 case 'L': 381 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 382 ret = 1; 383 goto done; 384 case 'x': 385 case 'X': 386 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 387 ret = 1; 388 goto done; 389 case 'c': 390 confirm = 1; 391 break; 392 case 'd': 393 deleting = 1; 394 break; 395 case 'D': 396 if (delete_all(ac) == -1) 397 ret = 1; 398 goto done; 399 case 's': 400 pkcs11provider = optarg; 401 break; 402 case 'e': 403 deleting = 1; 404 pkcs11provider = optarg; 405 break; 406 case 't': 407 if ((lifetime = convtime(optarg)) == -1) { 408 fprintf(stderr, "Invalid lifetime\n"); 409 ret = 1; 410 goto done; 411 } 412 break; 413 default: 414 usage(); 415 ret = 1; 416 goto done; 417 } 418 } 419 argc -= optind; 420 argv += optind; 421 if (pkcs11provider != NULL) { 422 if (update_card(ac, !deleting, pkcs11provider) == -1) 423 ret = 1; 424 goto done; 425 } 426 if (argc == 0) { 427 char buf[MAXPATHLEN]; 428 struct passwd *pw; 429 struct stat st; 430 int count = 0; 431 432 if ((pw = getpwuid(getuid())) == NULL) { 433 fprintf(stderr, "No user found with uid %u\n", 434 (u_int)getuid()); 435 ret = 1; 436 goto done; 437 } 438 439 for (i = 0; default_files[i]; i++) { 440 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 441 default_files[i]); 442 if (stat(buf, &st) < 0) 443 continue; 444 if (do_file(ac, deleting, buf) == -1) 445 ret = 1; 446 else 447 count++; 448 } 449 if (count == 0) 450 ret = 1; 451 } else { 452 for (i = 0; i < argc; i++) { 453 if (do_file(ac, deleting, argv[i]) == -1) 454 ret = 1; 455 } 456 } 457 clear_pass(); 458 459 done: 460 ssh_close_authentication_connection(ac); 461 return ret; 462 } 463