1 /* $OpenBSD: ssh-agent.c,v 1.214 2016/09/12 01:22:38 deraadt 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 * The authentication agent program. 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 * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <sys/types.h> 38 #include <sys/time.h> 39 #include <sys/queue.h> 40 #include <sys/resource.h> 41 #include <sys/socket.h> 42 #include <sys/stat.h> 43 #include <sys/un.h> 44 45 #ifdef WITH_OPENSSL 46 #include <openssl/evp.h> 47 #endif 48 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <paths.h> 52 #include <signal.h> 53 #include <stdlib.h> 54 #include <stdio.h> 55 #include <string.h> 56 #include <limits.h> 57 #include <time.h> 58 #include <unistd.h> 59 #include <util.h> 60 61 #include "xmalloc.h" 62 #include "ssh.h" 63 #include "rsa.h" 64 #include "sshbuf.h" 65 #include "sshkey.h" 66 #include "authfd.h" 67 #include "compat.h" 68 #include "log.h" 69 #include "misc.h" 70 #include "digest.h" 71 #include "ssherr.h" 72 73 #ifdef ENABLE_PKCS11 74 #include "ssh-pkcs11.h" 75 #endif 76 77 typedef enum { 78 AUTH_UNUSED, 79 AUTH_SOCKET, 80 AUTH_CONNECTION 81 } sock_type; 82 83 typedef struct { 84 int fd; 85 sock_type type; 86 struct sshbuf *input; 87 struct sshbuf *output; 88 struct sshbuf *request; 89 } SocketEntry; 90 91 u_int sockets_alloc = 0; 92 SocketEntry *sockets = NULL; 93 94 typedef struct identity { 95 TAILQ_ENTRY(identity) next; 96 struct sshkey *key; 97 char *comment; 98 char *provider; 99 time_t death; 100 u_int confirm; 101 } Identity; 102 103 typedef struct { 104 int nentries; 105 TAILQ_HEAD(idqueue, identity) idlist; 106 } Idtab; 107 108 /* private key table, one per protocol version */ 109 Idtab idtable[3]; 110 111 int max_fd = 0; 112 113 /* pid of shell == parent of agent */ 114 pid_t parent_pid = -1; 115 time_t parent_alive_interval = 0; 116 117 /* pid of process for which cleanup_socket is applicable */ 118 pid_t cleanup_pid = 0; 119 120 /* pathname and directory for AUTH_SOCKET */ 121 char socket_name[PATH_MAX]; 122 char socket_dir[PATH_MAX]; 123 124 /* locking */ 125 #define LOCK_SIZE 32 126 #define LOCK_SALT_SIZE 16 127 #define LOCK_ROUNDS 1 128 int locked = 0; 129 u_char lock_pwhash[LOCK_SIZE]; 130 u_char lock_salt[LOCK_SALT_SIZE]; 131 132 extern char *__progname; 133 134 /* Default lifetime in seconds (0 == forever) */ 135 static long lifetime = 0; 136 137 static int fingerprint_hash = SSH_FP_HASH_DEFAULT; 138 139 static void 140 close_socket(SocketEntry *e) 141 { 142 close(e->fd); 143 e->fd = -1; 144 e->type = AUTH_UNUSED; 145 sshbuf_free(e->input); 146 sshbuf_free(e->output); 147 sshbuf_free(e->request); 148 } 149 150 static void 151 idtab_init(void) 152 { 153 int i; 154 155 for (i = 0; i <=2; i++) { 156 TAILQ_INIT(&idtable[i].idlist); 157 idtable[i].nentries = 0; 158 } 159 } 160 161 /* return private key table for requested protocol version */ 162 static Idtab * 163 idtab_lookup(int version) 164 { 165 if (version < 1 || version > 2) 166 fatal("internal error, bad protocol version %d", version); 167 return &idtable[version]; 168 } 169 170 static void 171 free_identity(Identity *id) 172 { 173 sshkey_free(id->key); 174 free(id->provider); 175 free(id->comment); 176 free(id); 177 } 178 179 /* return matching private key for given public key */ 180 static Identity * 181 lookup_identity(struct sshkey *key, int version) 182 { 183 Identity *id; 184 185 Idtab *tab = idtab_lookup(version); 186 TAILQ_FOREACH(id, &tab->idlist, next) { 187 if (sshkey_equal(key, id->key)) 188 return (id); 189 } 190 return (NULL); 191 } 192 193 /* Check confirmation of keysign request */ 194 static int 195 confirm_key(Identity *id) 196 { 197 char *p; 198 int ret = -1; 199 200 p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT); 201 if (p != NULL && 202 ask_permission("Allow use of key %s?\nKey fingerprint %s.", 203 id->comment, p)) 204 ret = 0; 205 free(p); 206 207 return (ret); 208 } 209 210 static void 211 send_status(SocketEntry *e, int success) 212 { 213 int r; 214 215 if ((r = sshbuf_put_u32(e->output, 1)) != 0 || 216 (r = sshbuf_put_u8(e->output, success ? 217 SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0) 218 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 219 } 220 221 /* send list of supported public keys to 'client' */ 222 static void 223 process_request_identities(SocketEntry *e, int version) 224 { 225 Idtab *tab = idtab_lookup(version); 226 Identity *id; 227 struct sshbuf *msg; 228 int r; 229 230 if ((msg = sshbuf_new()) == NULL) 231 fatal("%s: sshbuf_new failed", __func__); 232 if ((r = sshbuf_put_u8(msg, (version == 1) ? 233 SSH_AGENT_RSA_IDENTITIES_ANSWER : 234 SSH2_AGENT_IDENTITIES_ANSWER)) != 0 || 235 (r = sshbuf_put_u32(msg, tab->nentries)) != 0) 236 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 237 TAILQ_FOREACH(id, &tab->idlist, next) { 238 if (id->key->type == KEY_RSA1) { 239 #ifdef WITH_SSH1 240 if ((r = sshbuf_put_u32(msg, 241 BN_num_bits(id->key->rsa->n))) != 0 || 242 (r = sshbuf_put_bignum1(msg, 243 id->key->rsa->e)) != 0 || 244 (r = sshbuf_put_bignum1(msg, 245 id->key->rsa->n)) != 0) 246 fatal("%s: buffer error: %s", 247 __func__, ssh_err(r)); 248 #endif 249 } else { 250 u_char *blob; 251 size_t blen; 252 253 if ((r = sshkey_to_blob(id->key, &blob, &blen)) != 0) { 254 error("%s: sshkey_to_blob: %s", __func__, 255 ssh_err(r)); 256 continue; 257 } 258 if ((r = sshbuf_put_string(msg, blob, blen)) != 0) 259 fatal("%s: buffer error: %s", 260 __func__, ssh_err(r)); 261 free(blob); 262 } 263 if ((r = sshbuf_put_cstring(msg, id->comment)) != 0) 264 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 265 } 266 if ((r = sshbuf_put_stringb(e->output, msg)) != 0) 267 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 268 sshbuf_free(msg); 269 } 270 271 #ifdef WITH_SSH1 272 /* ssh1 only */ 273 static void 274 process_authentication_challenge1(SocketEntry *e) 275 { 276 u_char buf[32], mdbuf[16], session_id[16]; 277 u_int response_type; 278 BIGNUM *challenge; 279 Identity *id; 280 int r, len; 281 struct sshbuf *msg; 282 struct ssh_digest_ctx *md; 283 struct sshkey *key; 284 285 if ((msg = sshbuf_new()) == NULL) 286 fatal("%s: sshbuf_new failed", __func__); 287 if ((key = sshkey_new(KEY_RSA1)) == NULL) 288 fatal("%s: sshkey_new failed", __func__); 289 if ((challenge = BN_new()) == NULL) 290 fatal("%s: BN_new failed", __func__); 291 292 if ((r = sshbuf_get_u32(e->request, NULL)) != 0 || /* ignored */ 293 (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 || 294 (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0 || 295 (r = sshbuf_get_bignum1(e->request, challenge))) 296 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 297 298 /* Only protocol 1.1 is supported */ 299 if (sshbuf_len(e->request) == 0) 300 goto failure; 301 if ((r = sshbuf_get(e->request, session_id, sizeof(session_id))) != 0 || 302 (r = sshbuf_get_u32(e->request, &response_type)) != 0) 303 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 304 if (response_type != 1) 305 goto failure; 306 307 id = lookup_identity(key, 1); 308 if (id != NULL && (!id->confirm || confirm_key(id) == 0)) { 309 struct sshkey *private = id->key; 310 /* Decrypt the challenge using the private key. */ 311 if ((r = rsa_private_decrypt(challenge, challenge, 312 private->rsa) != 0)) { 313 fatal("%s: rsa_public_encrypt: %s", __func__, 314 ssh_err(r)); 315 goto failure; /* XXX ? */ 316 } 317 318 /* The response is MD5 of decrypted challenge plus session id */ 319 len = BN_num_bytes(challenge); 320 if (len <= 0 || len > 32) { 321 logit("%s: bad challenge length %d", __func__, len); 322 goto failure; 323 } 324 memset(buf, 0, 32); 325 BN_bn2bin(challenge, buf + 32 - len); 326 if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL || 327 ssh_digest_update(md, buf, 32) < 0 || 328 ssh_digest_update(md, session_id, 16) < 0 || 329 ssh_digest_final(md, mdbuf, sizeof(mdbuf)) < 0) 330 fatal("%s: md5 failed", __func__); 331 ssh_digest_free(md); 332 333 /* Send the response. */ 334 if ((r = sshbuf_put_u8(msg, SSH_AGENT_RSA_RESPONSE)) != 0 || 335 (r = sshbuf_put(msg, mdbuf, sizeof(mdbuf))) != 0) 336 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 337 goto send; 338 } 339 340 failure: 341 /* Unknown identity or protocol error. Send failure. */ 342 if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0) 343 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 344 send: 345 if ((r = sshbuf_put_stringb(e->output, msg)) != 0) 346 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 347 sshkey_free(key); 348 BN_clear_free(challenge); 349 sshbuf_free(msg); 350 } 351 #endif 352 353 static char * 354 agent_decode_alg(struct sshkey *key, u_int flags) 355 { 356 if (key->type == KEY_RSA) { 357 if (flags & SSH_AGENT_RSA_SHA2_256) 358 return "rsa-sha2-256"; 359 else if (flags & SSH_AGENT_RSA_SHA2_512) 360 return "rsa-sha2-512"; 361 } 362 return NULL; 363 } 364 365 /* ssh2 only */ 366 static void 367 process_sign_request2(SocketEntry *e) 368 { 369 u_char *blob, *data, *signature = NULL; 370 size_t blen, dlen, slen = 0; 371 u_int compat = 0, flags; 372 int r, ok = -1; 373 struct sshbuf *msg; 374 struct sshkey *key; 375 struct identity *id; 376 377 if ((msg = sshbuf_new()) == NULL) 378 fatal("%s: sshbuf_new failed", __func__); 379 if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0 || 380 (r = sshbuf_get_string(e->request, &data, &dlen)) != 0 || 381 (r = sshbuf_get_u32(e->request, &flags)) != 0) 382 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 383 if (flags & SSH_AGENT_OLD_SIGNATURE) 384 compat = SSH_BUG_SIGBLOB; 385 if ((r = sshkey_from_blob(blob, blen, &key)) != 0) { 386 error("%s: cannot parse key blob: %s", __func__, ssh_err(r)); 387 goto send; 388 } 389 if ((id = lookup_identity(key, 2)) == NULL) { 390 verbose("%s: %s key not found", __func__, sshkey_type(key)); 391 goto send; 392 } 393 if (id->confirm && confirm_key(id) != 0) { 394 verbose("%s: user refused key", __func__); 395 goto send; 396 } 397 if ((r = sshkey_sign(id->key, &signature, &slen, 398 data, dlen, agent_decode_alg(key, flags), compat)) != 0) { 399 error("%s: sshkey_sign: %s", __func__, ssh_err(r)); 400 goto send; 401 } 402 /* Success */ 403 ok = 0; 404 send: 405 sshkey_free(key); 406 if (ok == 0) { 407 if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 || 408 (r = sshbuf_put_string(msg, signature, slen)) != 0) 409 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 410 } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0) 411 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 412 413 if ((r = sshbuf_put_stringb(e->output, msg)) != 0) 414 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 415 416 sshbuf_free(msg); 417 free(data); 418 free(blob); 419 free(signature); 420 } 421 422 /* shared */ 423 static void 424 process_remove_identity(SocketEntry *e, int version) 425 { 426 size_t blen; 427 int r, success = 0; 428 struct sshkey *key = NULL; 429 u_char *blob; 430 #ifdef WITH_SSH1 431 u_int bits; 432 #endif /* WITH_SSH1 */ 433 434 switch (version) { 435 #ifdef WITH_SSH1 436 case 1: 437 if ((key = sshkey_new(KEY_RSA1)) == NULL) { 438 error("%s: sshkey_new failed", __func__); 439 return; 440 } 441 if ((r = sshbuf_get_u32(e->request, &bits)) != 0 || 442 (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 || 443 (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0) 444 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 445 446 if (bits != sshkey_size(key)) 447 logit("Warning: identity keysize mismatch: " 448 "actual %u, announced %u", 449 sshkey_size(key), bits); 450 break; 451 #endif /* WITH_SSH1 */ 452 case 2: 453 if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0) 454 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 455 if ((r = sshkey_from_blob(blob, blen, &key)) != 0) 456 error("%s: sshkey_from_blob failed: %s", 457 __func__, ssh_err(r)); 458 free(blob); 459 break; 460 } 461 if (key != NULL) { 462 Identity *id = lookup_identity(key, version); 463 if (id != NULL) { 464 /* 465 * We have this key. Free the old key. Since we 466 * don't want to leave empty slots in the middle of 467 * the array, we actually free the key there and move 468 * all the entries between the empty slot and the end 469 * of the array. 470 */ 471 Idtab *tab = idtab_lookup(version); 472 if (tab->nentries < 1) 473 fatal("process_remove_identity: " 474 "internal error: tab->nentries %d", 475 tab->nentries); 476 TAILQ_REMOVE(&tab->idlist, id, next); 477 free_identity(id); 478 tab->nentries--; 479 success = 1; 480 } 481 sshkey_free(key); 482 } 483 send_status(e, success); 484 } 485 486 static void 487 process_remove_all_identities(SocketEntry *e, int version) 488 { 489 Idtab *tab = idtab_lookup(version); 490 Identity *id; 491 492 /* Loop over all identities and clear the keys. */ 493 for (id = TAILQ_FIRST(&tab->idlist); id; 494 id = TAILQ_FIRST(&tab->idlist)) { 495 TAILQ_REMOVE(&tab->idlist, id, next); 496 free_identity(id); 497 } 498 499 /* Mark that there are no identities. */ 500 tab->nentries = 0; 501 502 /* Send success. */ 503 send_status(e, 1); 504 } 505 506 /* removes expired keys and returns number of seconds until the next expiry */ 507 static time_t 508 reaper(void) 509 { 510 time_t deadline = 0, now = monotime(); 511 Identity *id, *nxt; 512 int version; 513 Idtab *tab; 514 515 for (version = 1; version < 3; version++) { 516 tab = idtab_lookup(version); 517 for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { 518 nxt = TAILQ_NEXT(id, next); 519 if (id->death == 0) 520 continue; 521 if (now >= id->death) { 522 debug("expiring key '%s'", id->comment); 523 TAILQ_REMOVE(&tab->idlist, id, next); 524 free_identity(id); 525 tab->nentries--; 526 } else 527 deadline = (deadline == 0) ? id->death : 528 MINIMUM(deadline, id->death); 529 } 530 } 531 if (deadline == 0 || deadline <= now) 532 return 0; 533 else 534 return (deadline - now); 535 } 536 537 /* 538 * XXX this and the corresponding serialisation function probably belongs 539 * in key.c 540 */ 541 #ifdef WITH_SSH1 542 static int 543 agent_decode_rsa1(struct sshbuf *m, struct sshkey **kp) 544 { 545 struct sshkey *k = NULL; 546 int r = SSH_ERR_INTERNAL_ERROR; 547 548 *kp = NULL; 549 if ((k = sshkey_new_private(KEY_RSA1)) == NULL) 550 return SSH_ERR_ALLOC_FAIL; 551 552 if ((r = sshbuf_get_u32(m, NULL)) != 0 || /* ignored */ 553 (r = sshbuf_get_bignum1(m, k->rsa->n)) != 0 || 554 (r = sshbuf_get_bignum1(m, k->rsa->e)) != 0 || 555 (r = sshbuf_get_bignum1(m, k->rsa->d)) != 0 || 556 (r = sshbuf_get_bignum1(m, k->rsa->iqmp)) != 0 || 557 /* SSH1 and SSL have p and q swapped */ 558 (r = sshbuf_get_bignum1(m, k->rsa->q)) != 0 || /* p */ 559 (r = sshbuf_get_bignum1(m, k->rsa->p)) != 0) /* q */ 560 goto out; 561 562 /* Generate additional parameters */ 563 if ((r = rsa_generate_additional_parameters(k->rsa)) != 0) 564 goto out; 565 /* enable blinding */ 566 if (RSA_blinding_on(k->rsa, NULL) != 1) { 567 r = SSH_ERR_LIBCRYPTO_ERROR; 568 goto out; 569 } 570 571 r = 0; /* success */ 572 out: 573 if (r == 0) 574 *kp = k; 575 else 576 sshkey_free(k); 577 return r; 578 } 579 #endif /* WITH_SSH1 */ 580 581 static void 582 process_add_identity(SocketEntry *e, int version) 583 { 584 Idtab *tab = idtab_lookup(version); 585 Identity *id; 586 int success = 0, confirm = 0; 587 u_int seconds; 588 char *comment = NULL; 589 time_t death = 0; 590 struct sshkey *k = NULL; 591 u_char ctype; 592 int r = SSH_ERR_INTERNAL_ERROR; 593 594 switch (version) { 595 #ifdef WITH_SSH1 596 case 1: 597 r = agent_decode_rsa1(e->request, &k); 598 break; 599 #endif /* WITH_SSH1 */ 600 case 2: 601 r = sshkey_private_deserialize(e->request, &k); 602 break; 603 } 604 if (r != 0 || k == NULL || 605 (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) { 606 error("%s: decode private key: %s", __func__, ssh_err(r)); 607 goto err; 608 } 609 610 while (sshbuf_len(e->request)) { 611 if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) { 612 error("%s: buffer error: %s", __func__, ssh_err(r)); 613 goto err; 614 } 615 switch (ctype) { 616 case SSH_AGENT_CONSTRAIN_LIFETIME: 617 if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) { 618 error("%s: bad lifetime constraint: %s", 619 __func__, ssh_err(r)); 620 goto err; 621 } 622 death = monotime() + seconds; 623 break; 624 case SSH_AGENT_CONSTRAIN_CONFIRM: 625 confirm = 1; 626 break; 627 default: 628 error("%s: Unknown constraint %d", __func__, ctype); 629 err: 630 sshbuf_reset(e->request); 631 free(comment); 632 sshkey_free(k); 633 goto send; 634 } 635 } 636 637 success = 1; 638 if (lifetime && !death) 639 death = monotime() + lifetime; 640 if ((id = lookup_identity(k, version)) == NULL) { 641 id = xcalloc(1, sizeof(Identity)); 642 id->key = k; 643 TAILQ_INSERT_TAIL(&tab->idlist, id, next); 644 /* Increment the number of identities. */ 645 tab->nentries++; 646 } else { 647 sshkey_free(k); 648 free(id->comment); 649 } 650 id->comment = comment; 651 id->death = death; 652 id->confirm = confirm; 653 send: 654 send_status(e, success); 655 } 656 657 /* XXX todo: encrypt sensitive data with passphrase */ 658 static void 659 process_lock_agent(SocketEntry *e, int lock) 660 { 661 int r, success = 0, delay; 662 char *passwd; 663 u_char passwdhash[LOCK_SIZE]; 664 static u_int fail_count = 0; 665 size_t pwlen; 666 667 if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0) 668 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 669 if (pwlen == 0) { 670 debug("empty password not supported"); 671 } else if (locked && !lock) { 672 if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt), 673 passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0) 674 fatal("bcrypt_pbkdf"); 675 if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) { 676 debug("agent unlocked"); 677 locked = 0; 678 fail_count = 0; 679 explicit_bzero(lock_pwhash, sizeof(lock_pwhash)); 680 success = 1; 681 } else { 682 /* delay in 0.1s increments up to 10s */ 683 if (fail_count < 100) 684 fail_count++; 685 delay = 100000 * fail_count; 686 debug("unlock failed, delaying %0.1lf seconds", 687 (double)delay/1000000); 688 usleep(delay); 689 } 690 explicit_bzero(passwdhash, sizeof(passwdhash)); 691 } else if (!locked && lock) { 692 debug("agent locked"); 693 locked = 1; 694 arc4random_buf(lock_salt, sizeof(lock_salt)); 695 if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt), 696 lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0) 697 fatal("bcrypt_pbkdf"); 698 success = 1; 699 } 700 explicit_bzero(passwd, pwlen); 701 free(passwd); 702 send_status(e, success); 703 } 704 705 static void 706 no_identities(SocketEntry *e, u_int type) 707 { 708 struct sshbuf *msg; 709 int r; 710 711 if ((msg = sshbuf_new()) == NULL) 712 fatal("%s: sshbuf_new failed", __func__); 713 if ((r = sshbuf_put_u8(msg, 714 (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ? 715 SSH_AGENT_RSA_IDENTITIES_ANSWER : 716 SSH2_AGENT_IDENTITIES_ANSWER)) != 0 || 717 (r = sshbuf_put_u32(msg, 0)) != 0 || 718 (r = sshbuf_put_stringb(e->output, msg)) != 0) 719 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 720 sshbuf_free(msg); 721 } 722 723 #ifdef ENABLE_PKCS11 724 static void 725 process_add_smartcard_key(SocketEntry *e) 726 { 727 char *provider = NULL, *pin; 728 int r, i, version, count = 0, success = 0, confirm = 0; 729 u_int seconds; 730 time_t death = 0; 731 u_char type; 732 struct sshkey **keys = NULL, *k; 733 Identity *id; 734 Idtab *tab; 735 736 if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 || 737 (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) 738 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 739 740 while (sshbuf_len(e->request)) { 741 if ((r = sshbuf_get_u8(e->request, &type)) != 0) 742 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 743 switch (type) { 744 case SSH_AGENT_CONSTRAIN_LIFETIME: 745 if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) 746 fatal("%s: buffer error: %s", 747 __func__, ssh_err(r)); 748 death = monotime() + seconds; 749 break; 750 case SSH_AGENT_CONSTRAIN_CONFIRM: 751 confirm = 1; 752 break; 753 default: 754 error("process_add_smartcard_key: " 755 "Unknown constraint type %d", type); 756 goto send; 757 } 758 } 759 if (lifetime && !death) 760 death = monotime() + lifetime; 761 762 count = pkcs11_add_provider(provider, pin, &keys); 763 for (i = 0; i < count; i++) { 764 k = keys[i]; 765 version = k->type == KEY_RSA1 ? 1 : 2; 766 tab = idtab_lookup(version); 767 if (lookup_identity(k, version) == NULL) { 768 id = xcalloc(1, sizeof(Identity)); 769 id->key = k; 770 id->provider = xstrdup(provider); 771 id->comment = xstrdup(provider); /* XXX */ 772 id->death = death; 773 id->confirm = confirm; 774 TAILQ_INSERT_TAIL(&tab->idlist, id, next); 775 tab->nentries++; 776 success = 1; 777 } else { 778 sshkey_free(k); 779 } 780 keys[i] = NULL; 781 } 782 send: 783 free(pin); 784 free(provider); 785 free(keys); 786 send_status(e, success); 787 } 788 789 static void 790 process_remove_smartcard_key(SocketEntry *e) 791 { 792 char *provider = NULL, *pin = NULL; 793 int r, version, success = 0; 794 Identity *id, *nxt; 795 Idtab *tab; 796 797 if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 || 798 (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) 799 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 800 free(pin); 801 802 for (version = 1; version < 3; version++) { 803 tab = idtab_lookup(version); 804 for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { 805 nxt = TAILQ_NEXT(id, next); 806 /* Skip file--based keys */ 807 if (id->provider == NULL) 808 continue; 809 if (!strcmp(provider, id->provider)) { 810 TAILQ_REMOVE(&tab->idlist, id, next); 811 free_identity(id); 812 tab->nentries--; 813 } 814 } 815 } 816 if (pkcs11_del_provider(provider) == 0) 817 success = 1; 818 else 819 error("process_remove_smartcard_key:" 820 " pkcs11_del_provider failed"); 821 free(provider); 822 send_status(e, success); 823 } 824 #endif /* ENABLE_PKCS11 */ 825 826 /* dispatch incoming messages */ 827 828 static void 829 process_message(SocketEntry *e) 830 { 831 u_int msg_len; 832 u_char type; 833 const u_char *cp; 834 int r; 835 836 if (sshbuf_len(e->input) < 5) 837 return; /* Incomplete message. */ 838 cp = sshbuf_ptr(e->input); 839 msg_len = PEEK_U32(cp); 840 if (msg_len > 256 * 1024) { 841 close_socket(e); 842 return; 843 } 844 if (sshbuf_len(e->input) < msg_len + 4) 845 return; 846 847 /* move the current input to e->request */ 848 sshbuf_reset(e->request); 849 if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 || 850 (r = sshbuf_get_u8(e->request, &type)) != 0) 851 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 852 853 /* check wheter agent is locked */ 854 if (locked && type != SSH_AGENTC_UNLOCK) { 855 sshbuf_reset(e->request); 856 switch (type) { 857 case SSH_AGENTC_REQUEST_RSA_IDENTITIES: 858 case SSH2_AGENTC_REQUEST_IDENTITIES: 859 /* send empty lists */ 860 no_identities(e, type); 861 break; 862 default: 863 /* send a fail message for all other request types */ 864 send_status(e, 0); 865 } 866 return; 867 } 868 869 debug("type %d", type); 870 switch (type) { 871 case SSH_AGENTC_LOCK: 872 case SSH_AGENTC_UNLOCK: 873 process_lock_agent(e, type == SSH_AGENTC_LOCK); 874 break; 875 #ifdef WITH_SSH1 876 /* ssh1 */ 877 case SSH_AGENTC_RSA_CHALLENGE: 878 process_authentication_challenge1(e); 879 break; 880 case SSH_AGENTC_REQUEST_RSA_IDENTITIES: 881 process_request_identities(e, 1); 882 break; 883 case SSH_AGENTC_ADD_RSA_IDENTITY: 884 case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED: 885 process_add_identity(e, 1); 886 break; 887 case SSH_AGENTC_REMOVE_RSA_IDENTITY: 888 process_remove_identity(e, 1); 889 break; 890 #endif 891 case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: 892 process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */ 893 break; 894 /* ssh2 */ 895 case SSH2_AGENTC_SIGN_REQUEST: 896 process_sign_request2(e); 897 break; 898 case SSH2_AGENTC_REQUEST_IDENTITIES: 899 process_request_identities(e, 2); 900 break; 901 case SSH2_AGENTC_ADD_IDENTITY: 902 case SSH2_AGENTC_ADD_ID_CONSTRAINED: 903 process_add_identity(e, 2); 904 break; 905 case SSH2_AGENTC_REMOVE_IDENTITY: 906 process_remove_identity(e, 2); 907 break; 908 case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: 909 process_remove_all_identities(e, 2); 910 break; 911 #ifdef ENABLE_PKCS11 912 case SSH_AGENTC_ADD_SMARTCARD_KEY: 913 case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED: 914 process_add_smartcard_key(e); 915 break; 916 case SSH_AGENTC_REMOVE_SMARTCARD_KEY: 917 process_remove_smartcard_key(e); 918 break; 919 #endif /* ENABLE_PKCS11 */ 920 default: 921 /* Unknown message. Respond with failure. */ 922 error("Unknown message %d", type); 923 sshbuf_reset(e->request); 924 send_status(e, 0); 925 break; 926 } 927 } 928 929 static void 930 new_socket(sock_type type, int fd) 931 { 932 u_int i, old_alloc, new_alloc; 933 934 set_nonblock(fd); 935 936 if (fd > max_fd) 937 max_fd = fd; 938 939 for (i = 0; i < sockets_alloc; i++) 940 if (sockets[i].type == AUTH_UNUSED) { 941 sockets[i].fd = fd; 942 if ((sockets[i].input = sshbuf_new()) == NULL) 943 fatal("%s: sshbuf_new failed", __func__); 944 if ((sockets[i].output = sshbuf_new()) == NULL) 945 fatal("%s: sshbuf_new failed", __func__); 946 if ((sockets[i].request = sshbuf_new()) == NULL) 947 fatal("%s: sshbuf_new failed", __func__); 948 sockets[i].type = type; 949 return; 950 } 951 old_alloc = sockets_alloc; 952 new_alloc = sockets_alloc + 10; 953 sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0])); 954 for (i = old_alloc; i < new_alloc; i++) 955 sockets[i].type = AUTH_UNUSED; 956 sockets_alloc = new_alloc; 957 sockets[old_alloc].fd = fd; 958 if ((sockets[old_alloc].input = sshbuf_new()) == NULL) 959 fatal("%s: sshbuf_new failed", __func__); 960 if ((sockets[old_alloc].output = sshbuf_new()) == NULL) 961 fatal("%s: sshbuf_new failed", __func__); 962 if ((sockets[old_alloc].request = sshbuf_new()) == NULL) 963 fatal("%s: sshbuf_new failed", __func__); 964 sockets[old_alloc].type = type; 965 } 966 967 static int 968 prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp, 969 struct timeval **tvpp) 970 { 971 u_int i, sz; 972 int n = 0; 973 static struct timeval tv; 974 time_t deadline; 975 976 for (i = 0; i < sockets_alloc; i++) { 977 switch (sockets[i].type) { 978 case AUTH_SOCKET: 979 case AUTH_CONNECTION: 980 n = MAXIMUM(n, sockets[i].fd); 981 break; 982 case AUTH_UNUSED: 983 break; 984 default: 985 fatal("Unknown socket type %d", sockets[i].type); 986 break; 987 } 988 } 989 990 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); 991 if (*fdrp == NULL || sz > *nallocp) { 992 free(*fdrp); 993 free(*fdwp); 994 *fdrp = xmalloc(sz); 995 *fdwp = xmalloc(sz); 996 *nallocp = sz; 997 } 998 if (n < *fdl) 999 debug("XXX shrink: %d < %d", n, *fdl); 1000 *fdl = n; 1001 memset(*fdrp, 0, sz); 1002 memset(*fdwp, 0, sz); 1003 1004 for (i = 0; i < sockets_alloc; i++) { 1005 switch (sockets[i].type) { 1006 case AUTH_SOCKET: 1007 case AUTH_CONNECTION: 1008 FD_SET(sockets[i].fd, *fdrp); 1009 if (sshbuf_len(sockets[i].output) > 0) 1010 FD_SET(sockets[i].fd, *fdwp); 1011 break; 1012 default: 1013 break; 1014 } 1015 } 1016 deadline = reaper(); 1017 if (parent_alive_interval != 0) 1018 deadline = (deadline == 0) ? parent_alive_interval : 1019 MINIMUM(deadline, parent_alive_interval); 1020 if (deadline == 0) { 1021 *tvpp = NULL; 1022 } else { 1023 tv.tv_sec = deadline; 1024 tv.tv_usec = 0; 1025 *tvpp = &tv; 1026 } 1027 return (1); 1028 } 1029 1030 static void 1031 after_select(fd_set *readset, fd_set *writeset) 1032 { 1033 struct sockaddr_un sunaddr; 1034 socklen_t slen; 1035 char buf[1024]; 1036 int len, sock, r; 1037 u_int i, orig_alloc; 1038 uid_t euid; 1039 gid_t egid; 1040 1041 for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++) 1042 switch (sockets[i].type) { 1043 case AUTH_UNUSED: 1044 break; 1045 case AUTH_SOCKET: 1046 if (FD_ISSET(sockets[i].fd, readset)) { 1047 slen = sizeof(sunaddr); 1048 sock = accept(sockets[i].fd, 1049 (struct sockaddr *)&sunaddr, &slen); 1050 if (sock < 0) { 1051 error("accept from AUTH_SOCKET: %s", 1052 strerror(errno)); 1053 break; 1054 } 1055 if (getpeereid(sock, &euid, &egid) < 0) { 1056 error("getpeereid %d failed: %s", 1057 sock, strerror(errno)); 1058 close(sock); 1059 break; 1060 } 1061 if ((euid != 0) && (getuid() != euid)) { 1062 error("uid mismatch: " 1063 "peer euid %u != uid %u", 1064 (u_int) euid, (u_int) getuid()); 1065 close(sock); 1066 break; 1067 } 1068 new_socket(AUTH_CONNECTION, sock); 1069 } 1070 break; 1071 case AUTH_CONNECTION: 1072 if (sshbuf_len(sockets[i].output) > 0 && 1073 FD_ISSET(sockets[i].fd, writeset)) { 1074 len = write(sockets[i].fd, 1075 sshbuf_ptr(sockets[i].output), 1076 sshbuf_len(sockets[i].output)); 1077 if (len == -1 && (errno == EAGAIN || 1078 errno == EINTR)) 1079 continue; 1080 if (len <= 0) { 1081 close_socket(&sockets[i]); 1082 break; 1083 } 1084 if ((r = sshbuf_consume(sockets[i].output, 1085 len)) != 0) 1086 fatal("%s: buffer error: %s", 1087 __func__, ssh_err(r)); 1088 } 1089 if (FD_ISSET(sockets[i].fd, readset)) { 1090 len = read(sockets[i].fd, buf, sizeof(buf)); 1091 if (len == -1 && (errno == EAGAIN || 1092 errno == EINTR)) 1093 continue; 1094 if (len <= 0) { 1095 close_socket(&sockets[i]); 1096 break; 1097 } 1098 if ((r = sshbuf_put(sockets[i].input, 1099 buf, len)) != 0) 1100 fatal("%s: buffer error: %s", 1101 __func__, ssh_err(r)); 1102 explicit_bzero(buf, sizeof(buf)); 1103 process_message(&sockets[i]); 1104 } 1105 break; 1106 default: 1107 fatal("Unknown type %d", sockets[i].type); 1108 } 1109 } 1110 1111 static void 1112 cleanup_socket(void) 1113 { 1114 if (cleanup_pid != 0 && getpid() != cleanup_pid) 1115 return; 1116 debug("%s: cleanup", __func__); 1117 if (socket_name[0]) 1118 unlink(socket_name); 1119 if (socket_dir[0]) 1120 rmdir(socket_dir); 1121 } 1122 1123 void 1124 cleanup_exit(int i) 1125 { 1126 cleanup_socket(); 1127 _exit(i); 1128 } 1129 1130 /*ARGSUSED*/ 1131 static void 1132 cleanup_handler(int sig) 1133 { 1134 cleanup_socket(); 1135 #ifdef ENABLE_PKCS11 1136 pkcs11_terminate(); 1137 #endif 1138 _exit(2); 1139 } 1140 1141 static void 1142 check_parent_exists(void) 1143 { 1144 /* 1145 * If our parent has exited then getppid() will return (pid_t)1, 1146 * so testing for that should be safe. 1147 */ 1148 if (parent_pid != -1 && getppid() != parent_pid) { 1149 /* printf("Parent has died - Authentication agent exiting.\n"); */ 1150 cleanup_socket(); 1151 _exit(2); 1152 } 1153 } 1154 1155 static void 1156 usage(void) 1157 { 1158 fprintf(stderr, 1159 "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n" 1160 " [-t life] [command [arg ...]]\n" 1161 " ssh-agent [-c | -s] -k\n"); 1162 exit(1); 1163 } 1164 1165 int 1166 main(int ac, char **av) 1167 { 1168 int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0; 1169 int sock, fd, ch, result, saved_errno; 1170 u_int nalloc; 1171 char *shell, *format, *pidstr, *agentsocket = NULL; 1172 fd_set *readsetp = NULL, *writesetp = NULL; 1173 struct rlimit rlim; 1174 extern int optind; 1175 extern char *optarg; 1176 pid_t pid; 1177 char pidstrbuf[1 + 3 * sizeof pid]; 1178 struct timeval *tvp = NULL; 1179 size_t len; 1180 mode_t prev_mask; 1181 1182 ssh_malloc_init(); /* must be called before any mallocs */ 1183 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 1184 sanitise_stdfd(); 1185 1186 /* drop */ 1187 setegid(getgid()); 1188 setgid(getgid()); 1189 1190 #ifdef WITH_OPENSSL 1191 OpenSSL_add_all_algorithms(); 1192 #endif 1193 1194 while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) { 1195 switch (ch) { 1196 case 'E': 1197 fingerprint_hash = ssh_digest_alg_by_name(optarg); 1198 if (fingerprint_hash == -1) 1199 fatal("Invalid hash algorithm \"%s\"", optarg); 1200 break; 1201 case 'c': 1202 if (s_flag) 1203 usage(); 1204 c_flag++; 1205 break; 1206 case 'k': 1207 k_flag++; 1208 break; 1209 case 's': 1210 if (c_flag) 1211 usage(); 1212 s_flag++; 1213 break; 1214 case 'd': 1215 if (d_flag || D_flag) 1216 usage(); 1217 d_flag++; 1218 break; 1219 case 'D': 1220 if (d_flag || D_flag) 1221 usage(); 1222 D_flag++; 1223 break; 1224 case 'a': 1225 agentsocket = optarg; 1226 break; 1227 case 't': 1228 if ((lifetime = convtime(optarg)) == -1) { 1229 fprintf(stderr, "Invalid lifetime\n"); 1230 usage(); 1231 } 1232 break; 1233 default: 1234 usage(); 1235 } 1236 } 1237 ac -= optind; 1238 av += optind; 1239 1240 if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag)) 1241 usage(); 1242 1243 if (ac == 0 && !c_flag && !s_flag) { 1244 shell = getenv("SHELL"); 1245 if (shell != NULL && (len = strlen(shell)) > 2 && 1246 strncmp(shell + len - 3, "csh", 3) == 0) 1247 c_flag = 1; 1248 } 1249 if (k_flag) { 1250 const char *errstr = NULL; 1251 1252 pidstr = getenv(SSH_AGENTPID_ENV_NAME); 1253 if (pidstr == NULL) { 1254 fprintf(stderr, "%s not set, cannot kill agent\n", 1255 SSH_AGENTPID_ENV_NAME); 1256 exit(1); 1257 } 1258 pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr); 1259 if (errstr) { 1260 fprintf(stderr, 1261 "%s=\"%s\", which is not a good PID: %s\n", 1262 SSH_AGENTPID_ENV_NAME, pidstr, errstr); 1263 exit(1); 1264 } 1265 if (kill(pid, SIGTERM) == -1) { 1266 perror("kill"); 1267 exit(1); 1268 } 1269 format = c_flag ? "unsetenv %s;\n" : "unset %s;\n"; 1270 printf(format, SSH_AUTHSOCKET_ENV_NAME); 1271 printf(format, SSH_AGENTPID_ENV_NAME); 1272 printf("echo Agent pid %ld killed;\n", (long)pid); 1273 exit(0); 1274 } 1275 parent_pid = getpid(); 1276 1277 if (agentsocket == NULL) { 1278 /* Create private directory for agent socket */ 1279 mktemp_proto(socket_dir, sizeof(socket_dir)); 1280 if (mkdtemp(socket_dir) == NULL) { 1281 perror("mkdtemp: private socket dir"); 1282 exit(1); 1283 } 1284 snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir, 1285 (long)parent_pid); 1286 } else { 1287 /* Try to use specified agent socket */ 1288 socket_dir[0] = '\0'; 1289 strlcpy(socket_name, agentsocket, sizeof socket_name); 1290 } 1291 1292 /* 1293 * Create socket early so it will exist before command gets run from 1294 * the parent. 1295 */ 1296 prev_mask = umask(0177); 1297 sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0); 1298 if (sock < 0) { 1299 /* XXX - unix_listener() calls error() not perror() */ 1300 *socket_name = '\0'; /* Don't unlink any existing file */ 1301 cleanup_exit(1); 1302 } 1303 umask(prev_mask); 1304 1305 /* 1306 * Fork, and have the parent execute the command, if any, or present 1307 * the socket data. The child continues as the authentication agent. 1308 */ 1309 if (D_flag || d_flag) { 1310 log_init(__progname, 1311 d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO, 1312 SYSLOG_FACILITY_AUTH, 1); 1313 format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; 1314 printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, 1315 SSH_AUTHSOCKET_ENV_NAME); 1316 printf("echo Agent pid %ld;\n", (long)parent_pid); 1317 fflush(stdout); 1318 goto skip; 1319 } 1320 pid = fork(); 1321 if (pid == -1) { 1322 perror("fork"); 1323 cleanup_exit(1); 1324 } 1325 if (pid != 0) { /* Parent - execute the given command. */ 1326 close(sock); 1327 snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid); 1328 if (ac == 0) { 1329 format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; 1330 printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, 1331 SSH_AUTHSOCKET_ENV_NAME); 1332 printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, 1333 SSH_AGENTPID_ENV_NAME); 1334 printf("echo Agent pid %ld;\n", (long)pid); 1335 exit(0); 1336 } 1337 if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || 1338 setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { 1339 perror("setenv"); 1340 exit(1); 1341 } 1342 execvp(av[0], av); 1343 perror(av[0]); 1344 exit(1); 1345 } 1346 /* child */ 1347 log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0); 1348 1349 if (setsid() == -1) { 1350 error("setsid: %s", strerror(errno)); 1351 cleanup_exit(1); 1352 } 1353 1354 (void)chdir("/"); 1355 if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 1356 /* XXX might close listen socket */ 1357 (void)dup2(fd, STDIN_FILENO); 1358 (void)dup2(fd, STDOUT_FILENO); 1359 (void)dup2(fd, STDERR_FILENO); 1360 if (fd > 2) 1361 close(fd); 1362 } 1363 1364 /* deny core dumps, since memory contains unencrypted private keys */ 1365 rlim.rlim_cur = rlim.rlim_max = 0; 1366 if (setrlimit(RLIMIT_CORE, &rlim) < 0) { 1367 error("setrlimit RLIMIT_CORE: %s", strerror(errno)); 1368 cleanup_exit(1); 1369 } 1370 1371 skip: 1372 1373 cleanup_pid = getpid(); 1374 1375 #ifdef ENABLE_PKCS11 1376 pkcs11_init(0); 1377 #endif 1378 new_socket(AUTH_SOCKET, sock); 1379 if (ac > 0) 1380 parent_alive_interval = 10; 1381 idtab_init(); 1382 signal(SIGPIPE, SIG_IGN); 1383 signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN); 1384 signal(SIGHUP, cleanup_handler); 1385 signal(SIGTERM, cleanup_handler); 1386 nalloc = 0; 1387 1388 if (pledge("stdio cpath unix id proc exec", NULL) == -1) 1389 fatal("%s: pledge: %s", __progname, strerror(errno)); 1390 1391 while (1) { 1392 prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp); 1393 result = select(max_fd + 1, readsetp, writesetp, NULL, tvp); 1394 saved_errno = errno; 1395 if (parent_alive_interval != 0) 1396 check_parent_exists(); 1397 (void) reaper(); /* remove expired keys */ 1398 if (result < 0) { 1399 if (saved_errno == EINTR) 1400 continue; 1401 fatal("select: %s", strerror(saved_errno)); 1402 } else if (result > 0) 1403 after_select(readsetp, writesetp); 1404 } 1405 /* NOTREACHED */ 1406 } 1407