1 /* $OpenBSD: ssh-add.c,v 1.94 2010/03/01 11:07:06 otto 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 has to 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 /* Graft with private bits */ 207 if (key_to_certified(private) != 0) 208 fatal("%s: key_to_certified failed", __func__); 209 key_cert_copy(cert, private); 210 key_free(cert); 211 212 if (ssh_add_identity_constrained(ac, private, comment, 213 lifetime, confirm)) { 214 fprintf(stderr, "Certificate added: %s (%s)\n", 215 certpath, private->cert->key_id); 216 if (lifetime != 0) 217 fprintf(stderr, "Lifetime set to %d seconds\n", 218 lifetime); 219 if (confirm != 0) 220 fprintf(stderr, "The user has to confirm each " 221 "use of the key\n"); 222 } else { 223 error("Certificate %s (%s) add failed", certpath, 224 private->cert->key_id); 225 } 226 } 227 228 xfree(certpath); 229 xfree(comment); 230 key_free(private); 231 232 return ret; 233 } 234 235 static int 236 update_card(AuthenticationConnection *ac, int add, const char *id) 237 { 238 char *pin; 239 int ret = -1; 240 241 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 242 if (pin == NULL) 243 return -1; 244 245 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 246 fprintf(stderr, "Card %s: %s\n", 247 add ? "added" : "removed", id); 248 ret = 0; 249 } else { 250 fprintf(stderr, "Could not %s card: %s\n", 251 add ? "add" : "remove", id); 252 ret = -1; 253 } 254 xfree(pin); 255 return ret; 256 } 257 258 static int 259 list_identities(AuthenticationConnection *ac, int do_fp) 260 { 261 Key *key; 262 char *comment, *fp; 263 int had_identities = 0; 264 int version; 265 266 for (version = 1; version <= 2; version++) { 267 for (key = ssh_get_first_identity(ac, &comment, version); 268 key != NULL; 269 key = ssh_get_next_identity(ac, &comment, version)) { 270 had_identities = 1; 271 if (do_fp) { 272 fp = key_fingerprint(key, SSH_FP_MD5, 273 SSH_FP_HEX); 274 printf("%d %s %s (%s)\n", 275 key_size(key), fp, comment, key_type(key)); 276 xfree(fp); 277 } else { 278 if (!key_write(key, stdout)) 279 fprintf(stderr, "key_write failed"); 280 fprintf(stdout, " %s\n", comment); 281 } 282 key_free(key); 283 xfree(comment); 284 } 285 } 286 if (!had_identities) { 287 printf("The agent has no identities.\n"); 288 return -1; 289 } 290 return 0; 291 } 292 293 static int 294 lock_agent(AuthenticationConnection *ac, int lock) 295 { 296 char prompt[100], *p1, *p2; 297 int passok = 1, ret = -1; 298 299 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 300 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 301 if (lock) { 302 strlcpy(prompt, "Again: ", sizeof prompt); 303 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 304 if (strcmp(p1, p2) != 0) { 305 fprintf(stderr, "Passwords do not match.\n"); 306 passok = 0; 307 } 308 memset(p2, 0, strlen(p2)); 309 xfree(p2); 310 } 311 if (passok && ssh_lock_agent(ac, lock, p1)) { 312 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 313 ret = 0; 314 } else 315 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 316 memset(p1, 0, strlen(p1)); 317 xfree(p1); 318 return (ret); 319 } 320 321 static int 322 do_file(AuthenticationConnection *ac, int deleting, char *file) 323 { 324 if (deleting) { 325 if (delete_file(ac, file) == -1) 326 return -1; 327 } else { 328 if (add_file(ac, file) == -1) 329 return -1; 330 } 331 return 0; 332 } 333 334 static void 335 usage(void) 336 { 337 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 338 fprintf(stderr, "Options:\n"); 339 fprintf(stderr, " -l List fingerprints of all identities.\n"); 340 fprintf(stderr, " -L List public key parameters of all identities.\n"); 341 fprintf(stderr, " -d Delete identity.\n"); 342 fprintf(stderr, " -D Delete all identities.\n"); 343 fprintf(stderr, " -x Lock agent.\n"); 344 fprintf(stderr, " -X Unlock agent.\n"); 345 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 346 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 347 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 348 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 349 } 350 351 int 352 main(int argc, char **argv) 353 { 354 extern char *optarg; 355 extern int optind; 356 AuthenticationConnection *ac = NULL; 357 char *pkcs11provider = NULL; 358 int i, ch, deleting = 0, ret = 0; 359 360 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 361 sanitise_stdfd(); 362 363 __progname = ssh_get_progname(argv[0]); 364 init_rng(); 365 seed_rng(); 366 367 SSLeay_add_all_algorithms(); 368 369 /* At first, get a connection to the authentication agent. */ 370 ac = ssh_get_authentication_connection(); 371 if (ac == NULL) { 372 fprintf(stderr, 373 "Could not open a connection to your authentication agent.\n"); 374 exit(2); 375 } 376 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 377 switch (ch) { 378 case 'l': 379 case 'L': 380 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 381 ret = 1; 382 goto done; 383 case 'x': 384 case 'X': 385 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 386 ret = 1; 387 goto done; 388 case 'c': 389 confirm = 1; 390 break; 391 case 'd': 392 deleting = 1; 393 break; 394 case 'D': 395 if (delete_all(ac) == -1) 396 ret = 1; 397 goto done; 398 case 's': 399 pkcs11provider = optarg; 400 break; 401 case 'e': 402 deleting = 1; 403 pkcs11provider = optarg; 404 break; 405 case 't': 406 if ((lifetime = convtime(optarg)) == -1) { 407 fprintf(stderr, "Invalid lifetime\n"); 408 ret = 1; 409 goto done; 410 } 411 break; 412 default: 413 usage(); 414 ret = 1; 415 goto done; 416 } 417 } 418 argc -= optind; 419 argv += optind; 420 if (pkcs11provider != NULL) { 421 if (update_card(ac, !deleting, pkcs11provider) == -1) 422 ret = 1; 423 goto done; 424 } 425 if (argc == 0) { 426 char buf[MAXPATHLEN]; 427 struct passwd *pw; 428 struct stat st; 429 int count = 0; 430 431 if ((pw = getpwuid(getuid())) == NULL) { 432 fprintf(stderr, "No user found with uid %u\n", 433 (u_int)getuid()); 434 ret = 1; 435 goto done; 436 } 437 438 for (i = 0; default_files[i]; i++) { 439 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 440 default_files[i]); 441 if (stat(buf, &st) < 0) 442 continue; 443 if (do_file(ac, deleting, buf) == -1) 444 ret = 1; 445 else 446 count++; 447 } 448 if (count == 0) 449 ret = 1; 450 } else { 451 for (i = 0; i < argc; i++) { 452 if (do_file(ac, deleting, argv[i]) == -1) 453 ret = 1; 454 } 455 } 456 clear_pass(); 457 458 done: 459 ssh_close_authentication_connection(ac); 460 return ret; 461 } 462