1 /* $OpenBSD: ssh-add.c,v 1.95 2010/04/16 01:47:26 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_IDENTITY, 70 NULL 71 }; 72 73 /* Default lifetime (0 == forever) */ 74 static int lifetime = 0; 75 76 /* User has to confirm key use */ 77 static int confirm = 0; 78 79 /* we keep a cache of one passphrases */ 80 static char *pass = NULL; 81 static void 82 clear_pass(void) 83 { 84 if (pass) { 85 memset(pass, 0, strlen(pass)); 86 xfree(pass); 87 pass = NULL; 88 } 89 } 90 91 static int 92 delete_file(AuthenticationConnection *ac, const char *filename) 93 { 94 Key *public; 95 char *comment = NULL; 96 int ret = -1; 97 98 public = key_load_public(filename, &comment); 99 if (public == NULL) { 100 printf("Bad key file %s\n", filename); 101 return -1; 102 } 103 if (ssh_remove_identity(ac, public)) { 104 fprintf(stderr, "Identity removed: %s (%s)\n", filename, comment); 105 ret = 0; 106 } else 107 fprintf(stderr, "Could not remove identity: %s\n", filename); 108 109 key_free(public); 110 xfree(comment); 111 112 return ret; 113 } 114 115 /* Send a request to remove all identities. */ 116 static int 117 delete_all(AuthenticationConnection *ac) 118 { 119 int ret = -1; 120 121 if (ssh_remove_all_identities(ac, 1)) 122 ret = 0; 123 /* ignore error-code for ssh2 */ 124 ssh_remove_all_identities(ac, 2); 125 126 if (ret == 0) 127 fprintf(stderr, "All identities removed.\n"); 128 else 129 fprintf(stderr, "Failed to remove all identities.\n"); 130 131 return ret; 132 } 133 134 static int 135 add_file(AuthenticationConnection *ac, const char *filename) 136 { 137 Key *private, *cert; 138 char *comment = NULL; 139 char msg[1024], *certpath; 140 int fd, perms_ok, ret = -1; 141 142 if ((fd = open(filename, O_RDONLY)) < 0) { 143 perror(filename); 144 return -1; 145 } 146 147 /* 148 * Since we'll try to load a keyfile multiple times, permission errors 149 * will occur multiple times, so check perms first and bail if wrong. 150 */ 151 perms_ok = key_perm_ok(fd, filename); 152 close(fd); 153 if (!perms_ok) 154 return -1; 155 156 /* At first, try empty passphrase */ 157 private = key_load_private(filename, "", &comment); 158 if (comment == NULL) 159 comment = xstrdup(filename); 160 /* try last */ 161 if (private == NULL && pass != NULL) 162 private = key_load_private(filename, pass, NULL); 163 if (private == NULL) { 164 /* clear passphrase since it did not work */ 165 clear_pass(); 166 snprintf(msg, sizeof msg, "Enter passphrase for %.200s: ", 167 comment); 168 for (;;) { 169 pass = read_passphrase(msg, RP_ALLOW_STDIN); 170 if (strcmp(pass, "") == 0) { 171 clear_pass(); 172 xfree(comment); 173 return -1; 174 } 175 private = key_load_private(filename, pass, &comment); 176 if (private != NULL) 177 break; 178 clear_pass(); 179 snprintf(msg, sizeof msg, 180 "Bad passphrase, try again for %.200s: ", comment); 181 } 182 } 183 184 if (ssh_add_identity_constrained(ac, private, comment, lifetime, 185 confirm)) { 186 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 187 ret = 0; 188 if (lifetime != 0) 189 fprintf(stderr, 190 "Lifetime set to %d seconds\n", lifetime); 191 if (confirm != 0) 192 fprintf(stderr, 193 "The user has to confirm each use of the key\n"); 194 } else { 195 fprintf(stderr, "Could not add identity: %s\n", filename); 196 } 197 198 199 /* Now try to add the certificate flavour too */ 200 xasprintf(&certpath, "%s-cert.pub", filename); 201 if ((cert = key_load_public(certpath, NULL)) != NULL) { 202 /* Graft with private bits */ 203 if (key_to_certified(private, key_cert_is_legacy(cert)) != 0) 204 fatal("%s: key_to_certified failed", __func__); 205 key_cert_copy(cert, private); 206 key_free(cert); 207 208 if (ssh_add_identity_constrained(ac, private, comment, 209 lifetime, confirm)) { 210 fprintf(stderr, "Certificate added: %s (%s)\n", 211 certpath, private->cert->key_id); 212 if (lifetime != 0) 213 fprintf(stderr, "Lifetime set to %d seconds\n", 214 lifetime); 215 if (confirm != 0) 216 fprintf(stderr, "The user has to confirm each " 217 "use of the key\n"); 218 } else { 219 error("Certificate %s (%s) add failed", certpath, 220 private->cert->key_id); 221 } 222 } 223 224 xfree(certpath); 225 xfree(comment); 226 key_free(private); 227 228 return ret; 229 } 230 231 static int 232 update_card(AuthenticationConnection *ac, int add, const char *id) 233 { 234 char *pin; 235 int ret = -1; 236 237 pin = read_passphrase("Enter passphrase for PKCS#11: ", RP_ALLOW_STDIN); 238 if (pin == NULL) 239 return -1; 240 241 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 242 fprintf(stderr, "Card %s: %s\n", 243 add ? "added" : "removed", id); 244 ret = 0; 245 } else { 246 fprintf(stderr, "Could not %s card: %s\n", 247 add ? "add" : "remove", id); 248 ret = -1; 249 } 250 xfree(pin); 251 return ret; 252 } 253 254 static int 255 list_identities(AuthenticationConnection *ac, int do_fp) 256 { 257 Key *key; 258 char *comment, *fp; 259 int had_identities = 0; 260 int version; 261 262 for (version = 1; version <= 2; version++) { 263 for (key = ssh_get_first_identity(ac, &comment, version); 264 key != NULL; 265 key = ssh_get_next_identity(ac, &comment, version)) { 266 had_identities = 1; 267 if (do_fp) { 268 fp = key_fingerprint(key, SSH_FP_MD5, 269 SSH_FP_HEX); 270 printf("%d %s %s (%s)\n", 271 key_size(key), fp, comment, key_type(key)); 272 xfree(fp); 273 } else { 274 if (!key_write(key, stdout)) 275 fprintf(stderr, "key_write failed"); 276 fprintf(stdout, " %s\n", comment); 277 } 278 key_free(key); 279 xfree(comment); 280 } 281 } 282 if (!had_identities) { 283 printf("The agent has no identities.\n"); 284 return -1; 285 } 286 return 0; 287 } 288 289 static int 290 lock_agent(AuthenticationConnection *ac, int lock) 291 { 292 char prompt[100], *p1, *p2; 293 int passok = 1, ret = -1; 294 295 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 296 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 297 if (lock) { 298 strlcpy(prompt, "Again: ", sizeof prompt); 299 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 300 if (strcmp(p1, p2) != 0) { 301 fprintf(stderr, "Passwords do not match.\n"); 302 passok = 0; 303 } 304 memset(p2, 0, strlen(p2)); 305 xfree(p2); 306 } 307 if (passok && ssh_lock_agent(ac, lock, p1)) { 308 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 309 ret = 0; 310 } else 311 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 312 memset(p1, 0, strlen(p1)); 313 xfree(p1); 314 return (ret); 315 } 316 317 static int 318 do_file(AuthenticationConnection *ac, int deleting, char *file) 319 { 320 if (deleting) { 321 if (delete_file(ac, file) == -1) 322 return -1; 323 } else { 324 if (add_file(ac, file) == -1) 325 return -1; 326 } 327 return 0; 328 } 329 330 static void 331 usage(void) 332 { 333 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 334 fprintf(stderr, "Options:\n"); 335 fprintf(stderr, " -l List fingerprints of all identities.\n"); 336 fprintf(stderr, " -L List public key parameters of all identities.\n"); 337 fprintf(stderr, " -d Delete identity.\n"); 338 fprintf(stderr, " -D Delete all identities.\n"); 339 fprintf(stderr, " -x Lock agent.\n"); 340 fprintf(stderr, " -X Unlock agent.\n"); 341 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 342 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 343 fprintf(stderr, " -s pkcs11 Add keys from PKCS#11 provider.\n"); 344 fprintf(stderr, " -e pkcs11 Remove keys provided by PKCS#11 provider.\n"); 345 } 346 347 int 348 main(int argc, char **argv) 349 { 350 extern char *optarg; 351 extern int optind; 352 AuthenticationConnection *ac = NULL; 353 char *pkcs11provider = NULL; 354 int i, ch, deleting = 0, ret = 0; 355 356 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 357 sanitise_stdfd(); 358 359 SSLeay_add_all_algorithms(); 360 361 /* At first, get a connection to the authentication agent. */ 362 ac = ssh_get_authentication_connection(); 363 if (ac == NULL) { 364 fprintf(stderr, 365 "Could not open a connection to your authentication agent.\n"); 366 exit(2); 367 } 368 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 369 switch (ch) { 370 case 'l': 371 case 'L': 372 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 373 ret = 1; 374 goto done; 375 case 'x': 376 case 'X': 377 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 378 ret = 1; 379 goto done; 380 case 'c': 381 confirm = 1; 382 break; 383 case 'd': 384 deleting = 1; 385 break; 386 case 'D': 387 if (delete_all(ac) == -1) 388 ret = 1; 389 goto done; 390 case 's': 391 pkcs11provider = optarg; 392 break; 393 case 'e': 394 deleting = 1; 395 pkcs11provider = optarg; 396 break; 397 case 't': 398 if ((lifetime = convtime(optarg)) == -1) { 399 fprintf(stderr, "Invalid lifetime\n"); 400 ret = 1; 401 goto done; 402 } 403 break; 404 default: 405 usage(); 406 ret = 1; 407 goto done; 408 } 409 } 410 argc -= optind; 411 argv += optind; 412 if (pkcs11provider != NULL) { 413 if (update_card(ac, !deleting, pkcs11provider) == -1) 414 ret = 1; 415 goto done; 416 } 417 if (argc == 0) { 418 char buf[MAXPATHLEN]; 419 struct passwd *pw; 420 struct stat st; 421 int count = 0; 422 423 if ((pw = getpwuid(getuid())) == NULL) { 424 fprintf(stderr, "No user found with uid %u\n", 425 (u_int)getuid()); 426 ret = 1; 427 goto done; 428 } 429 430 for (i = 0; default_files[i]; i++) { 431 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 432 default_files[i]); 433 if (stat(buf, &st) < 0) 434 continue; 435 if (do_file(ac, deleting, buf) == -1) 436 ret = 1; 437 else 438 count++; 439 } 440 if (count == 0) 441 ret = 1; 442 } else { 443 for (i = 0; i < argc; i++) { 444 if (do_file(ac, deleting, argv[i]) == -1) 445 ret = 1; 446 } 447 } 448 clear_pass(); 449 450 done: 451 ssh_close_authentication_connection(ac); 452 return ret; 453 } 454