1 /* $OpenBSD: ssh-add.c,v 1.90 2007/09/09 11:38:01 sobrado 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; 138 char *comment = NULL; 139 char msg[1024]; 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 if (ssh_add_identity(ac, private, comment)) { 195 fprintf(stderr, "Identity added: %s (%s)\n", filename, comment); 196 ret = 0; 197 } else { 198 fprintf(stderr, "Could not add identity: %s\n", filename); 199 } 200 201 xfree(comment); 202 key_free(private); 203 204 return ret; 205 } 206 207 static int 208 update_card(AuthenticationConnection *ac, int add, const char *id) 209 { 210 char *pin; 211 int ret = -1; 212 213 pin = read_passphrase("Enter passphrase for smartcard: ", RP_ALLOW_STDIN); 214 if (pin == NULL) 215 return -1; 216 217 if (ssh_update_card(ac, add, id, pin, lifetime, confirm)) { 218 fprintf(stderr, "Card %s: %s\n", 219 add ? "added" : "removed", id); 220 ret = 0; 221 } else { 222 fprintf(stderr, "Could not %s card: %s\n", 223 add ? "add" : "remove", id); 224 ret = -1; 225 } 226 xfree(pin); 227 return ret; 228 } 229 230 static int 231 list_identities(AuthenticationConnection *ac, int do_fp) 232 { 233 Key *key; 234 char *comment, *fp; 235 int had_identities = 0; 236 int version; 237 238 for (version = 1; version <= 2; version++) { 239 for (key = ssh_get_first_identity(ac, &comment, version); 240 key != NULL; 241 key = ssh_get_next_identity(ac, &comment, version)) { 242 had_identities = 1; 243 if (do_fp) { 244 fp = key_fingerprint(key, SSH_FP_MD5, 245 SSH_FP_HEX); 246 printf("%d %s %s (%s)\n", 247 key_size(key), fp, comment, key_type(key)); 248 xfree(fp); 249 } else { 250 if (!key_write(key, stdout)) 251 fprintf(stderr, "key_write failed"); 252 fprintf(stdout, " %s\n", comment); 253 } 254 key_free(key); 255 xfree(comment); 256 } 257 } 258 if (!had_identities) { 259 printf("The agent has no identities.\n"); 260 return -1; 261 } 262 return 0; 263 } 264 265 static int 266 lock_agent(AuthenticationConnection *ac, int lock) 267 { 268 char prompt[100], *p1, *p2; 269 int passok = 1, ret = -1; 270 271 strlcpy(prompt, "Enter lock password: ", sizeof(prompt)); 272 p1 = read_passphrase(prompt, RP_ALLOW_STDIN); 273 if (lock) { 274 strlcpy(prompt, "Again: ", sizeof prompt); 275 p2 = read_passphrase(prompt, RP_ALLOW_STDIN); 276 if (strcmp(p1, p2) != 0) { 277 fprintf(stderr, "Passwords do not match.\n"); 278 passok = 0; 279 } 280 memset(p2, 0, strlen(p2)); 281 xfree(p2); 282 } 283 if (passok && ssh_lock_agent(ac, lock, p1)) { 284 fprintf(stderr, "Agent %slocked.\n", lock ? "" : "un"); 285 ret = 0; 286 } else 287 fprintf(stderr, "Failed to %slock agent.\n", lock ? "" : "un"); 288 memset(p1, 0, strlen(p1)); 289 xfree(p1); 290 return (ret); 291 } 292 293 static int 294 do_file(AuthenticationConnection *ac, int deleting, char *file) 295 { 296 if (deleting) { 297 if (delete_file(ac, file) == -1) 298 return -1; 299 } else { 300 if (add_file(ac, file) == -1) 301 return -1; 302 } 303 return 0; 304 } 305 306 static void 307 usage(void) 308 { 309 fprintf(stderr, "usage: %s [options] [file ...]\n", __progname); 310 fprintf(stderr, "Options:\n"); 311 fprintf(stderr, " -l List fingerprints of all identities.\n"); 312 fprintf(stderr, " -L List public key parameters of all identities.\n"); 313 fprintf(stderr, " -d Delete identity.\n"); 314 fprintf(stderr, " -D Delete all identities.\n"); 315 fprintf(stderr, " -x Lock agent.\n"); 316 fprintf(stderr, " -X Unlock agent.\n"); 317 fprintf(stderr, " -t life Set lifetime (in seconds) when adding identities.\n"); 318 fprintf(stderr, " -c Require confirmation to sign using identities\n"); 319 #ifdef SMARTCARD 320 fprintf(stderr, " -s reader Add key in smartcard reader.\n"); 321 fprintf(stderr, " -e reader Remove key in smartcard reader.\n"); 322 #endif 323 } 324 325 int 326 main(int argc, char **argv) 327 { 328 extern char *optarg; 329 extern int optind; 330 AuthenticationConnection *ac = NULL; 331 char *sc_reader_id = NULL; 332 int i, ch, deleting = 0, ret = 0; 333 334 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 335 sanitise_stdfd(); 336 337 SSLeay_add_all_algorithms(); 338 339 /* At first, get a connection to the authentication agent. */ 340 ac = ssh_get_authentication_connection(); 341 if (ac == NULL) { 342 fprintf(stderr, 343 "Could not open a connection to your authentication agent.\n"); 344 exit(2); 345 } 346 while ((ch = getopt(argc, argv, "lLcdDxXe:s:t:")) != -1) { 347 switch (ch) { 348 case 'l': 349 case 'L': 350 if (list_identities(ac, ch == 'l' ? 1 : 0) == -1) 351 ret = 1; 352 goto done; 353 case 'x': 354 case 'X': 355 if (lock_agent(ac, ch == 'x' ? 1 : 0) == -1) 356 ret = 1; 357 goto done; 358 case 'c': 359 confirm = 1; 360 break; 361 case 'd': 362 deleting = 1; 363 break; 364 case 'D': 365 if (delete_all(ac) == -1) 366 ret = 1; 367 goto done; 368 case 's': 369 sc_reader_id = optarg; 370 break; 371 case 'e': 372 deleting = 1; 373 sc_reader_id = optarg; 374 break; 375 case 't': 376 if ((lifetime = convtime(optarg)) == -1) { 377 fprintf(stderr, "Invalid lifetime\n"); 378 ret = 1; 379 goto done; 380 } 381 break; 382 default: 383 usage(); 384 ret = 1; 385 goto done; 386 } 387 } 388 argc -= optind; 389 argv += optind; 390 if (sc_reader_id != NULL) { 391 if (update_card(ac, !deleting, sc_reader_id) == -1) 392 ret = 1; 393 goto done; 394 } 395 if (argc == 0) { 396 char buf[MAXPATHLEN]; 397 struct passwd *pw; 398 struct stat st; 399 int count = 0; 400 401 if ((pw = getpwuid(getuid())) == NULL) { 402 fprintf(stderr, "No user found with uid %u\n", 403 (u_int)getuid()); 404 ret = 1; 405 goto done; 406 } 407 408 for (i = 0; default_files[i]; i++) { 409 snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, 410 default_files[i]); 411 if (stat(buf, &st) < 0) 412 continue; 413 if (do_file(ac, deleting, buf) == -1) 414 ret = 1; 415 else 416 count++; 417 } 418 if (count == 0) 419 ret = 1; 420 } else { 421 for (i = 0; i < argc; i++) { 422 if (do_file(ac, deleting, argv[i]) == -1) 423 ret = 1; 424 } 425 } 426 clear_pass(); 427 428 done: 429 ssh_close_authentication_connection(ac); 430 return ret; 431 } 432