1 /* $NetBSD: ssh-agent.c,v 1.12 2013/11/08 19:18:25 christos Exp $ */ 2 /* $OpenBSD: ssh-agent.c,v 1.177 2013/07/20 01:50:20 djm Exp $ */ 3 /* 4 * Author: Tatu Ylonen <ylo@cs.hut.fi> 5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 6 * All rights reserved 7 * The authentication agent program. 8 * 9 * As far as I am concerned, the code I have written for this software 10 * can be used freely for any purpose. Any derived versions of this 11 * software must be clearly marked as such, and if the derived work is 12 * incompatible with the protocol description in the RFC file, it must be 13 * called by a name other than "ssh" or "Secure Shell". 14 * 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 __RCSID("$NetBSD: ssh-agent.c,v 1.12 2013/11/08 19:18:25 christos Exp $"); 40 #include <sys/types.h> 41 #include <sys/time.h> 42 #include <sys/queue.h> 43 #include <sys/resource.h> 44 #include <sys/types.h> 45 #include <sys/socket.h> 46 #include <sys/un.h> 47 #include <sys/param.h> 48 49 #include <openssl/evp.h> 50 #include <openssl/md5.h> 51 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <paths.h> 55 #include <signal.h> 56 #include <stdlib.h> 57 #include <stdio.h> 58 #include <string.h> 59 #include <time.h> 60 #include <unistd.h> 61 62 #include "xmalloc.h" 63 #include "ssh.h" 64 #include "rsa.h" 65 #include "buffer.h" 66 #include "key.h" 67 #include "authfd.h" 68 #include "compat.h" 69 #include "log.h" 70 #include "misc.h" 71 #include "getpeereid.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 Buffer input; 87 Buffer output; 88 Buffer 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 Key *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 /* pathname and directory for AUTH_SOCKET */ 118 char socket_name[MAXPATHLEN]; 119 char socket_dir[MAXPATHLEN]; 120 121 /* locking */ 122 int locked = 0; 123 char *lock_passwd = NULL; 124 125 extern char *__progname; 126 127 /* Default lifetime in seconds (0 == forever) */ 128 static long lifetime = 0; 129 130 static void 131 close_socket(SocketEntry *e) 132 { 133 close(e->fd); 134 e->fd = -1; 135 e->type = AUTH_UNUSED; 136 buffer_free(&e->input); 137 buffer_free(&e->output); 138 buffer_free(&e->request); 139 } 140 141 static void 142 idtab_init(void) 143 { 144 int i; 145 146 for (i = 0; i <=2; i++) { 147 TAILQ_INIT(&idtable[i].idlist); 148 idtable[i].nentries = 0; 149 } 150 } 151 152 /* return private key table for requested protocol version */ 153 static Idtab * 154 idtab_lookup(int version) 155 { 156 if (version < 1 || version > 2) 157 fatal("internal error, bad protocol version %d", version); 158 return &idtable[version]; 159 } 160 161 static void 162 free_identity(Identity *id) 163 { 164 key_free(id->key); 165 free(id->provider); 166 free(id->comment); 167 free(id); 168 } 169 170 /* return matching private key for given public key */ 171 static Identity * 172 lookup_identity(Key *key, int version) 173 { 174 Identity *id; 175 176 Idtab *tab = idtab_lookup(version); 177 TAILQ_FOREACH(id, &tab->idlist, next) { 178 if (key_equal(key, id->key)) 179 return (id); 180 } 181 return (NULL); 182 } 183 184 /* Check confirmation of keysign request */ 185 static int 186 confirm_key(Identity *id) 187 { 188 char *p; 189 int ret = -1; 190 191 p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX); 192 if (ask_permission("Allow use of key %s?\nKey fingerprint %s.", 193 id->comment, p)) 194 ret = 0; 195 free(p); 196 197 return (ret); 198 } 199 200 /* send list of supported public keys to 'client' */ 201 static void 202 process_request_identities(SocketEntry *e, int version) 203 { 204 Idtab *tab = idtab_lookup(version); 205 Identity *id; 206 Buffer msg; 207 208 buffer_init(&msg); 209 buffer_put_char(&msg, (version == 1) ? 210 SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); 211 buffer_put_int(&msg, tab->nentries); 212 TAILQ_FOREACH(id, &tab->idlist, next) { 213 if (id->key->type == KEY_RSA1) { 214 buffer_put_int(&msg, BN_num_bits(id->key->rsa->n)); 215 buffer_put_bignum(&msg, id->key->rsa->e); 216 buffer_put_bignum(&msg, id->key->rsa->n); 217 } else { 218 u_char *blob; 219 u_int blen; 220 key_to_blob(id->key, &blob, &blen); 221 buffer_put_string(&msg, blob, blen); 222 free(blob); 223 } 224 buffer_put_cstring(&msg, id->comment); 225 } 226 buffer_put_int(&e->output, buffer_len(&msg)); 227 buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); 228 buffer_free(&msg); 229 } 230 231 /* ssh1 only */ 232 static void 233 process_authentication_challenge1(SocketEntry *e) 234 { 235 u_char buf[32], mdbuf[16], session_id[16]; 236 u_int response_type; 237 BIGNUM *challenge; 238 Identity *id; 239 int i, len; 240 Buffer msg; 241 MD5_CTX md; 242 Key *key; 243 244 buffer_init(&msg); 245 key = key_new(KEY_RSA1); 246 if ((challenge = BN_new()) == NULL) 247 fatal("process_authentication_challenge1: BN_new failed"); 248 249 (void) buffer_get_int(&e->request); /* ignored */ 250 buffer_get_bignum(&e->request, key->rsa->e); 251 buffer_get_bignum(&e->request, key->rsa->n); 252 buffer_get_bignum(&e->request, challenge); 253 254 /* Only protocol 1.1 is supported */ 255 if (buffer_len(&e->request) == 0) 256 goto failure; 257 buffer_get(&e->request, session_id, 16); 258 response_type = buffer_get_int(&e->request); 259 if (response_type != 1) 260 goto failure; 261 262 id = lookup_identity(key, 1); 263 if (id != NULL && (!id->confirm || confirm_key(id) == 0)) { 264 Key *private = id->key; 265 /* Decrypt the challenge using the private key. */ 266 if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0) 267 goto failure; 268 269 /* The response is MD5 of decrypted challenge plus session id. */ 270 len = BN_num_bytes(challenge); 271 if (len <= 0 || len > 32) { 272 logit("process_authentication_challenge: bad challenge length %d", len); 273 goto failure; 274 } 275 memset(buf, 0, 32); 276 BN_bn2bin(challenge, buf + 32 - len); 277 MD5_Init(&md); 278 MD5_Update(&md, buf, 32); 279 MD5_Update(&md, session_id, 16); 280 MD5_Final(mdbuf, &md); 281 282 /* Send the response. */ 283 buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE); 284 for (i = 0; i < 16; i++) 285 buffer_put_char(&msg, mdbuf[i]); 286 goto send; 287 } 288 289 failure: 290 /* Unknown identity or protocol error. Send failure. */ 291 buffer_put_char(&msg, SSH_AGENT_FAILURE); 292 send: 293 buffer_put_int(&e->output, buffer_len(&msg)); 294 buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); 295 key_free(key); 296 BN_clear_free(challenge); 297 buffer_free(&msg); 298 } 299 300 /* ssh2 only */ 301 static void 302 process_sign_request2(SocketEntry *e) 303 { 304 u_char *blob, *data, *signature = NULL; 305 u_int blen, dlen, slen = 0; 306 extern int datafellows; 307 int odatafellows; 308 int ok = -1, flags; 309 Buffer msg; 310 Key *key; 311 312 odatafellows = datafellows; 313 datafellows = 0; 314 315 blob = buffer_get_string(&e->request, &blen); 316 data = buffer_get_string(&e->request, &dlen); 317 318 flags = buffer_get_int(&e->request); 319 if (flags & SSH_AGENT_OLD_SIGNATURE) 320 datafellows = SSH_BUG_SIGBLOB; 321 322 key = key_from_blob(blob, blen); 323 if (key != NULL) { 324 Identity *id = lookup_identity(key, 2); 325 if (id != NULL && (!id->confirm || confirm_key(id) == 0)) 326 ok = key_sign(id->key, &signature, &slen, data, dlen); 327 key_free(key); 328 } 329 buffer_init(&msg); 330 if (ok == 0) { 331 buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE); 332 buffer_put_string(&msg, signature, slen); 333 } else { 334 buffer_put_char(&msg, SSH_AGENT_FAILURE); 335 } 336 buffer_put_int(&e->output, buffer_len(&msg)); 337 buffer_append(&e->output, buffer_ptr(&msg), 338 buffer_len(&msg)); 339 buffer_free(&msg); 340 free(data); 341 free(blob); 342 free(signature); 343 datafellows = odatafellows; 344 } 345 346 /* shared */ 347 static void 348 process_remove_identity(SocketEntry *e, int version) 349 { 350 u_int blen, bits; 351 int success = 0; 352 Key *key = NULL; 353 u_char *blob; 354 355 switch (version) { 356 case 1: 357 key = key_new(KEY_RSA1); 358 bits = buffer_get_int(&e->request); 359 buffer_get_bignum(&e->request, key->rsa->e); 360 buffer_get_bignum(&e->request, key->rsa->n); 361 362 if (bits != key_size(key)) 363 logit("Warning: identity keysize mismatch: actual %u, announced %u", 364 key_size(key), bits); 365 break; 366 case 2: 367 blob = buffer_get_string(&e->request, &blen); 368 key = key_from_blob(blob, blen); 369 free(blob); 370 break; 371 } 372 if (key != NULL) { 373 Identity *id = lookup_identity(key, version); 374 if (id != NULL) { 375 /* 376 * We have this key. Free the old key. Since we 377 * don't want to leave empty slots in the middle of 378 * the array, we actually free the key there and move 379 * all the entries between the empty slot and the end 380 * of the array. 381 */ 382 Idtab *tab = idtab_lookup(version); 383 if (tab->nentries < 1) 384 fatal("process_remove_identity: " 385 "internal error: tab->nentries %d", 386 tab->nentries); 387 TAILQ_REMOVE(&tab->idlist, id, next); 388 free_identity(id); 389 tab->nentries--; 390 success = 1; 391 } 392 key_free(key); 393 } 394 buffer_put_int(&e->output, 1); 395 buffer_put_char(&e->output, 396 success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); 397 } 398 399 static void 400 process_remove_all_identities(SocketEntry *e, int version) 401 { 402 Idtab *tab = idtab_lookup(version); 403 Identity *id; 404 405 /* Loop over all identities and clear the keys. */ 406 while ((id = TAILQ_FIRST(&tab->idlist)) != NULL) { 407 TAILQ_REMOVE(&tab->idlist, id, next); 408 free_identity(id); 409 } 410 411 /* Mark that there are no identities. */ 412 tab->nentries = 0; 413 414 /* Send success. */ 415 buffer_put_int(&e->output, 1); 416 buffer_put_char(&e->output, SSH_AGENT_SUCCESS); 417 } 418 419 /* removes expired keys and returns number of seconds until the next expiry */ 420 static time_t 421 reaper(void) 422 { 423 time_t deadline = 0, now = monotime(); 424 Identity *id, *nxt; 425 int version; 426 Idtab *tab; 427 428 for (version = 1; version < 3; version++) { 429 tab = idtab_lookup(version); 430 for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { 431 nxt = TAILQ_NEXT(id, next); 432 if (id->death == 0) 433 continue; 434 if (now >= id->death) { 435 debug("expiring key '%s'", id->comment); 436 TAILQ_REMOVE(&tab->idlist, id, next); 437 free_identity(id); 438 tab->nentries--; 439 } else 440 deadline = (deadline == 0) ? id->death : 441 MIN(deadline, id->death); 442 } 443 } 444 if (deadline == 0 || deadline <= now) 445 return 0; 446 else 447 return (deadline - now); 448 } 449 450 static void 451 process_add_identity(SocketEntry *e, int version) 452 { 453 Idtab *tab = idtab_lookup(version); 454 Identity *id; 455 int type, success = 0, confirm = 0; 456 char *type_name, *comment, *curve; 457 time_t death = 0; 458 Key *k = NULL; 459 BIGNUM *exponent; 460 EC_POINT *q; 461 u_char *cert; 462 u_int len; 463 464 switch (version) { 465 case 1: 466 k = key_new_private(KEY_RSA1); 467 (void) buffer_get_int(&e->request); /* ignored */ 468 buffer_get_bignum(&e->request, k->rsa->n); 469 buffer_get_bignum(&e->request, k->rsa->e); 470 buffer_get_bignum(&e->request, k->rsa->d); 471 buffer_get_bignum(&e->request, k->rsa->iqmp); 472 473 /* SSH and SSL have p and q swapped */ 474 buffer_get_bignum(&e->request, k->rsa->q); /* p */ 475 buffer_get_bignum(&e->request, k->rsa->p); /* q */ 476 477 /* Generate additional parameters */ 478 rsa_generate_additional_parameters(k->rsa); 479 break; 480 case 2: 481 type_name = buffer_get_string(&e->request, NULL); 482 type = key_type_from_name(type_name); 483 switch (type) { 484 case KEY_DSA: 485 k = key_new_private(type); 486 buffer_get_bignum2(&e->request, k->dsa->p); 487 buffer_get_bignum2(&e->request, k->dsa->q); 488 buffer_get_bignum2(&e->request, k->dsa->g); 489 buffer_get_bignum2(&e->request, k->dsa->pub_key); 490 buffer_get_bignum2(&e->request, k->dsa->priv_key); 491 break; 492 case KEY_DSA_CERT_V00: 493 case KEY_DSA_CERT: 494 cert = buffer_get_string(&e->request, &len); 495 if ((k = key_from_blob(cert, len)) == NULL) 496 fatal("Certificate parse failed"); 497 free(cert); 498 key_add_private(k); 499 buffer_get_bignum2(&e->request, k->dsa->priv_key); 500 break; 501 case KEY_ECDSA: 502 k = key_new_private(type); 503 k->ecdsa_nid = key_ecdsa_nid_from_name(type_name); 504 curve = buffer_get_string(&e->request, NULL); 505 if (k->ecdsa_nid != key_curve_name_to_nid(curve)) 506 fatal("%s: curve names mismatch", __func__); 507 free(curve); 508 k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid); 509 if (k->ecdsa == NULL) 510 fatal("%s: EC_KEY_new_by_curve_name failed", 511 __func__); 512 q = EC_POINT_new(EC_KEY_get0_group(k->ecdsa)); 513 if (q == NULL) 514 fatal("%s: BN_new failed", __func__); 515 if ((exponent = BN_new()) == NULL) 516 fatal("%s: BN_new failed", __func__); 517 buffer_get_ecpoint(&e->request, 518 EC_KEY_get0_group(k->ecdsa), q); 519 buffer_get_bignum2(&e->request, exponent); 520 if (EC_KEY_set_public_key(k->ecdsa, q) != 1) 521 fatal("%s: EC_KEY_set_public_key failed", 522 __func__); 523 if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) 524 fatal("%s: EC_KEY_set_private_key failed", 525 __func__); 526 if (key_ec_validate_public(EC_KEY_get0_group(k->ecdsa), 527 EC_KEY_get0_public_key(k->ecdsa)) != 0) 528 fatal("%s: bad ECDSA public key", __func__); 529 if (key_ec_validate_private(k->ecdsa) != 0) 530 fatal("%s: bad ECDSA private key", __func__); 531 BN_clear_free(exponent); 532 EC_POINT_free(q); 533 break; 534 case KEY_ECDSA_CERT: 535 cert = buffer_get_string(&e->request, &len); 536 if ((k = key_from_blob(cert, len)) == NULL) 537 fatal("Certificate parse failed"); 538 free(cert); 539 key_add_private(k); 540 if ((exponent = BN_new()) == NULL) 541 fatal("%s: BN_new failed", __func__); 542 buffer_get_bignum2(&e->request, exponent); 543 if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1) 544 fatal("%s: EC_KEY_set_private_key failed", 545 __func__); 546 if (key_ec_validate_public(EC_KEY_get0_group(k->ecdsa), 547 EC_KEY_get0_public_key(k->ecdsa)) != 0 || 548 key_ec_validate_private(k->ecdsa) != 0) 549 fatal("%s: bad ECDSA key", __func__); 550 BN_clear_free(exponent); 551 break; 552 case KEY_RSA: 553 k = key_new_private(type); 554 buffer_get_bignum2(&e->request, k->rsa->n); 555 buffer_get_bignum2(&e->request, k->rsa->e); 556 buffer_get_bignum2(&e->request, k->rsa->d); 557 buffer_get_bignum2(&e->request, k->rsa->iqmp); 558 buffer_get_bignum2(&e->request, k->rsa->p); 559 buffer_get_bignum2(&e->request, k->rsa->q); 560 561 /* Generate additional parameters */ 562 rsa_generate_additional_parameters(k->rsa); 563 break; 564 case KEY_RSA_CERT_V00: 565 case KEY_RSA_CERT: 566 cert = buffer_get_string(&e->request, &len); 567 if ((k = key_from_blob(cert, len)) == NULL) 568 fatal("Certificate parse failed"); 569 free(cert); 570 key_add_private(k); 571 buffer_get_bignum2(&e->request, k->rsa->d); 572 buffer_get_bignum2(&e->request, k->rsa->iqmp); 573 buffer_get_bignum2(&e->request, k->rsa->p); 574 buffer_get_bignum2(&e->request, k->rsa->q); 575 break; 576 default: 577 free(type_name); 578 buffer_clear(&e->request); 579 goto send; 580 } 581 free(type_name); 582 break; 583 } 584 /* enable blinding */ 585 switch (k->type) { 586 case KEY_RSA: 587 case KEY_RSA_CERT_V00: 588 case KEY_RSA_CERT: 589 case KEY_RSA1: 590 if (RSA_blinding_on(k->rsa, NULL) != 1) { 591 error("process_add_identity: RSA_blinding_on failed"); 592 key_free(k); 593 goto send; 594 } 595 break; 596 } 597 comment = buffer_get_string(&e->request, NULL); 598 if (k == NULL) { 599 free(comment); 600 goto send; 601 } 602 while (buffer_len(&e->request)) { 603 switch ((type = buffer_get_char(&e->request))) { 604 case SSH_AGENT_CONSTRAIN_LIFETIME: 605 death = monotime() + buffer_get_int(&e->request); 606 break; 607 case SSH_AGENT_CONSTRAIN_CONFIRM: 608 confirm = 1; 609 break; 610 default: 611 error("process_add_identity: " 612 "Unknown constraint type %d", type); 613 free(comment); 614 key_free(k); 615 goto send; 616 } 617 } 618 success = 1; 619 if (lifetime && !death) 620 death = monotime() + lifetime; 621 if ((id = lookup_identity(k, version)) == NULL) { 622 id = xcalloc(1, sizeof(Identity)); 623 id->key = k; 624 TAILQ_INSERT_TAIL(&tab->idlist, id, next); 625 /* Increment the number of identities. */ 626 tab->nentries++; 627 } else { 628 key_free(k); 629 free(id->comment); 630 } 631 id->comment = comment; 632 id->death = death; 633 id->confirm = confirm; 634 send: 635 buffer_put_int(&e->output, 1); 636 buffer_put_char(&e->output, 637 success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); 638 } 639 640 /* XXX todo: encrypt sensitive data with passphrase */ 641 static void 642 process_lock_agent(SocketEntry *e, int lock) 643 { 644 int success = 0; 645 char *passwd; 646 647 passwd = buffer_get_string(&e->request, NULL); 648 if (locked && !lock && strcmp(passwd, lock_passwd) == 0) { 649 locked = 0; 650 memset(lock_passwd, 0, strlen(lock_passwd)); 651 free(lock_passwd); 652 lock_passwd = NULL; 653 success = 1; 654 } else if (!locked && lock) { 655 locked = 1; 656 lock_passwd = xstrdup(passwd); 657 success = 1; 658 } 659 memset(passwd, 0, strlen(passwd)); 660 free(passwd); 661 662 buffer_put_int(&e->output, 1); 663 buffer_put_char(&e->output, 664 success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); 665 } 666 667 static void 668 no_identities(SocketEntry *e, u_int type) 669 { 670 Buffer msg; 671 672 buffer_init(&msg); 673 buffer_put_char(&msg, 674 (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ? 675 SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); 676 buffer_put_int(&msg, 0); 677 buffer_put_int(&e->output, buffer_len(&msg)); 678 buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); 679 buffer_free(&msg); 680 } 681 682 #ifdef ENABLE_PKCS11 683 static void 684 process_add_smartcard_key(SocketEntry *e) 685 { 686 char *provider = NULL, *pin; 687 int i, type, version, count = 0, success = 0, confirm = 0; 688 time_t death = 0; 689 Key **keys = NULL, *k; 690 Identity *id; 691 Idtab *tab; 692 693 provider = buffer_get_string(&e->request, NULL); 694 pin = buffer_get_string(&e->request, NULL); 695 696 while (buffer_len(&e->request)) { 697 switch ((type = buffer_get_char(&e->request))) { 698 case SSH_AGENT_CONSTRAIN_LIFETIME: 699 death = monotime() + buffer_get_int(&e->request); 700 break; 701 case SSH_AGENT_CONSTRAIN_CONFIRM: 702 confirm = 1; 703 break; 704 default: 705 error("process_add_smartcard_key: " 706 "Unknown constraint type %d", type); 707 goto send; 708 } 709 } 710 if (lifetime && !death) 711 death = monotime() + lifetime; 712 713 count = pkcs11_add_provider(provider, pin, &keys); 714 for (i = 0; i < count; i++) { 715 k = keys[i]; 716 version = k->type == KEY_RSA1 ? 1 : 2; 717 tab = idtab_lookup(version); 718 if (lookup_identity(k, version) == NULL) { 719 id = xcalloc(1, sizeof(Identity)); 720 id->key = k; 721 id->provider = xstrdup(provider); 722 id->comment = xstrdup(provider); /* XXX */ 723 id->death = death; 724 id->confirm = confirm; 725 TAILQ_INSERT_TAIL(&tab->idlist, id, next); 726 tab->nentries++; 727 success = 1; 728 } else { 729 key_free(k); 730 } 731 keys[i] = NULL; 732 } 733 send: 734 free(pin); 735 free(provider); 736 free(keys); 737 buffer_put_int(&e->output, 1); 738 buffer_put_char(&e->output, 739 success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); 740 } 741 742 static void 743 process_remove_smartcard_key(SocketEntry *e) 744 { 745 char *provider = NULL, *pin = NULL; 746 int version, success = 0; 747 Identity *id, *nxt; 748 Idtab *tab; 749 750 provider = buffer_get_string(&e->request, NULL); 751 pin = buffer_get_string(&e->request, NULL); 752 free(pin); 753 754 for (version = 1; version < 3; version++) { 755 tab = idtab_lookup(version); 756 for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { 757 nxt = TAILQ_NEXT(id, next); 758 if (!strcmp(provider, id->provider)) { 759 TAILQ_REMOVE(&tab->idlist, id, next); 760 free_identity(id); 761 tab->nentries--; 762 } 763 } 764 } 765 if (pkcs11_del_provider(provider) == 0) 766 success = 1; 767 else 768 error("process_remove_smartcard_key:" 769 " pkcs11_del_provider failed"); 770 free(provider); 771 buffer_put_int(&e->output, 1); 772 buffer_put_char(&e->output, 773 success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); 774 } 775 #endif /* ENABLE_PKCS11 */ 776 777 /* dispatch incoming messages */ 778 779 static void 780 process_message(SocketEntry *e) 781 { 782 u_int msg_len, type; 783 u_char *cp; 784 785 if (buffer_len(&e->input) < 5) 786 return; /* Incomplete message. */ 787 cp = buffer_ptr(&e->input); 788 msg_len = get_u32(cp); 789 if (msg_len > 256 * 1024) { 790 close_socket(e); 791 return; 792 } 793 if (buffer_len(&e->input) < msg_len + 4) 794 return; 795 796 /* move the current input to e->request */ 797 buffer_consume(&e->input, 4); 798 buffer_clear(&e->request); 799 buffer_append(&e->request, buffer_ptr(&e->input), msg_len); 800 buffer_consume(&e->input, msg_len); 801 type = buffer_get_char(&e->request); 802 803 /* check wheter agent is locked */ 804 if (locked && type != SSH_AGENTC_UNLOCK) { 805 buffer_clear(&e->request); 806 switch (type) { 807 case SSH_AGENTC_REQUEST_RSA_IDENTITIES: 808 case SSH2_AGENTC_REQUEST_IDENTITIES: 809 /* send empty lists */ 810 no_identities(e, type); 811 break; 812 default: 813 /* send a fail message for all other request types */ 814 buffer_put_int(&e->output, 1); 815 buffer_put_char(&e->output, SSH_AGENT_FAILURE); 816 } 817 return; 818 } 819 820 debug("type %d", type); 821 switch (type) { 822 case SSH_AGENTC_LOCK: 823 case SSH_AGENTC_UNLOCK: 824 process_lock_agent(e, type == SSH_AGENTC_LOCK); 825 break; 826 /* ssh1 */ 827 case SSH_AGENTC_RSA_CHALLENGE: 828 process_authentication_challenge1(e); 829 break; 830 case SSH_AGENTC_REQUEST_RSA_IDENTITIES: 831 process_request_identities(e, 1); 832 break; 833 case SSH_AGENTC_ADD_RSA_IDENTITY: 834 case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED: 835 process_add_identity(e, 1); 836 break; 837 case SSH_AGENTC_REMOVE_RSA_IDENTITY: 838 process_remove_identity(e, 1); 839 break; 840 case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: 841 process_remove_all_identities(e, 1); 842 break; 843 /* ssh2 */ 844 case SSH2_AGENTC_SIGN_REQUEST: 845 process_sign_request2(e); 846 break; 847 case SSH2_AGENTC_REQUEST_IDENTITIES: 848 process_request_identities(e, 2); 849 break; 850 case SSH2_AGENTC_ADD_IDENTITY: 851 case SSH2_AGENTC_ADD_ID_CONSTRAINED: 852 process_add_identity(e, 2); 853 break; 854 case SSH2_AGENTC_REMOVE_IDENTITY: 855 process_remove_identity(e, 2); 856 break; 857 case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: 858 process_remove_all_identities(e, 2); 859 break; 860 #ifdef ENABLE_PKCS11 861 case SSH_AGENTC_ADD_SMARTCARD_KEY: 862 case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED: 863 process_add_smartcard_key(e); 864 break; 865 case SSH_AGENTC_REMOVE_SMARTCARD_KEY: 866 process_remove_smartcard_key(e); 867 break; 868 #endif /* ENABLE_PKCS11 */ 869 default: 870 /* Unknown message. Respond with failure. */ 871 error("Unknown message %d", type); 872 buffer_clear(&e->request); 873 buffer_put_int(&e->output, 1); 874 buffer_put_char(&e->output, SSH_AGENT_FAILURE); 875 break; 876 } 877 } 878 879 static void 880 new_socket(sock_type type, int fd) 881 { 882 u_int i, old_alloc, new_alloc; 883 884 set_nonblock(fd); 885 886 if (fd > max_fd) 887 max_fd = fd; 888 889 for (i = 0; i < sockets_alloc; i++) 890 if (sockets[i].type == AUTH_UNUSED) { 891 sockets[i].fd = fd; 892 buffer_init(&sockets[i].input); 893 buffer_init(&sockets[i].output); 894 buffer_init(&sockets[i].request); 895 sockets[i].type = type; 896 return; 897 } 898 old_alloc = sockets_alloc; 899 new_alloc = sockets_alloc + 10; 900 sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0])); 901 for (i = old_alloc; i < new_alloc; i++) 902 sockets[i].type = AUTH_UNUSED; 903 sockets_alloc = new_alloc; 904 sockets[old_alloc].fd = fd; 905 buffer_init(&sockets[old_alloc].input); 906 buffer_init(&sockets[old_alloc].output); 907 buffer_init(&sockets[old_alloc].request); 908 sockets[old_alloc].type = type; 909 } 910 911 static int 912 prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp, 913 struct timeval **tvpp) 914 { 915 u_int i, sz; 916 int n = 0; 917 static struct timeval tv; 918 time_t deadline; 919 920 for (i = 0; i < sockets_alloc; i++) { 921 switch (sockets[i].type) { 922 case AUTH_SOCKET: 923 case AUTH_CONNECTION: 924 n = MAX(n, sockets[i].fd); 925 break; 926 case AUTH_UNUSED: 927 break; 928 default: 929 fatal("Unknown socket type %d", sockets[i].type); 930 break; 931 } 932 } 933 934 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); 935 if (*fdrp == NULL || sz > *nallocp) { 936 free(*fdrp); 937 free(*fdwp); 938 *fdrp = xmalloc(sz); 939 *fdwp = xmalloc(sz); 940 *nallocp = sz; 941 } 942 if (n < *fdl) 943 debug("XXX shrink: %d < %d", n, *fdl); 944 *fdl = n; 945 memset(*fdrp, 0, sz); 946 memset(*fdwp, 0, sz); 947 948 for (i = 0; i < sockets_alloc; i++) { 949 switch (sockets[i].type) { 950 case AUTH_SOCKET: 951 case AUTH_CONNECTION: 952 FD_SET(sockets[i].fd, *fdrp); 953 if (buffer_len(&sockets[i].output) > 0) 954 FD_SET(sockets[i].fd, *fdwp); 955 break; 956 default: 957 break; 958 } 959 } 960 deadline = reaper(); 961 if (parent_alive_interval != 0) 962 deadline = (deadline == 0) ? parent_alive_interval : 963 MIN(deadline, parent_alive_interval); 964 if (deadline == 0) { 965 *tvpp = NULL; 966 } else { 967 tv.tv_sec = deadline; 968 tv.tv_usec = 0; 969 *tvpp = &tv; 970 } 971 return (1); 972 } 973 974 static void 975 after_select(fd_set *readset, fd_set *writeset) 976 { 977 struct sockaddr_un sunaddr; 978 socklen_t slen; 979 char buf[1024]; 980 int len, sock; 981 u_int i, orig_alloc; 982 uid_t euid; 983 gid_t egid; 984 985 for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++) 986 switch (sockets[i].type) { 987 case AUTH_UNUSED: 988 break; 989 case AUTH_SOCKET: 990 if (FD_ISSET(sockets[i].fd, readset)) { 991 slen = sizeof(sunaddr); 992 sock = accept(sockets[i].fd, 993 (struct sockaddr *)&sunaddr, &slen); 994 if (sock < 0) { 995 error("accept from AUTH_SOCKET: %s", 996 strerror(errno)); 997 break; 998 } 999 if (getpeereid(sock, &euid, &egid) < 0) { 1000 error("getpeereid %d failed: %s", 1001 sock, strerror(errno)); 1002 close(sock); 1003 break; 1004 } 1005 if ((euid != 0) && (getuid() != euid)) { 1006 error("uid mismatch: " 1007 "peer euid %u != uid %u", 1008 (u_int) euid, (u_int) getuid()); 1009 close(sock); 1010 break; 1011 } 1012 new_socket(AUTH_CONNECTION, sock); 1013 } 1014 break; 1015 case AUTH_CONNECTION: 1016 if (buffer_len(&sockets[i].output) > 0 && 1017 FD_ISSET(sockets[i].fd, writeset)) { 1018 len = write(sockets[i].fd, 1019 buffer_ptr(&sockets[i].output), 1020 buffer_len(&sockets[i].output)); 1021 if (len == -1 && (errno == EAGAIN || 1022 errno == EINTR)) 1023 continue; 1024 if (len <= 0) { 1025 close_socket(&sockets[i]); 1026 break; 1027 } 1028 buffer_consume(&sockets[i].output, len); 1029 } 1030 if (FD_ISSET(sockets[i].fd, readset)) { 1031 len = read(sockets[i].fd, buf, sizeof(buf)); 1032 if (len == -1 && (errno == EAGAIN || 1033 errno == EINTR)) 1034 continue; 1035 if (len <= 0) { 1036 close_socket(&sockets[i]); 1037 break; 1038 } 1039 buffer_append(&sockets[i].input, buf, len); 1040 process_message(&sockets[i]); 1041 } 1042 break; 1043 default: 1044 fatal("Unknown type %d", sockets[i].type); 1045 } 1046 } 1047 1048 static void 1049 cleanup_socket(void) 1050 { 1051 if (socket_name[0]) 1052 unlink(socket_name); 1053 if (socket_dir[0]) 1054 rmdir(socket_dir); 1055 } 1056 1057 void 1058 cleanup_exit(int i) 1059 { 1060 cleanup_socket(); 1061 _exit(i); 1062 } 1063 1064 /*ARGSUSED*/ 1065 __dead static void 1066 cleanup_handler(int sig) 1067 { 1068 cleanup_socket(); 1069 #ifdef ENABLE_PKCS11 1070 pkcs11_terminate(); 1071 #endif 1072 _exit(2); 1073 } 1074 1075 static void 1076 check_parent_exists(void) 1077 { 1078 /* 1079 * If our parent has exited then getppid() will return (pid_t)1, 1080 * so testing for that should be safe. 1081 */ 1082 if (parent_pid != -1 && getppid() != parent_pid) { 1083 /* printf("Parent has died - Authentication agent exiting.\n"); */ 1084 cleanup_socket(); 1085 _exit(2); 1086 } 1087 } 1088 1089 __dead static void 1090 usage(void) 1091 { 1092 fprintf(stderr, "usage: %s [options] [command [arg ...]]\n", 1093 __progname); 1094 fprintf(stderr, "Options:\n"); 1095 fprintf(stderr, " -c Generate C-shell commands on stdout.\n"); 1096 fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n"); 1097 fprintf(stderr, " -k Kill the current agent.\n"); 1098 fprintf(stderr, " -d Debug mode.\n"); 1099 fprintf(stderr, " -a socket Bind agent socket to given name.\n"); 1100 fprintf(stderr, " -t life Default identity lifetime (seconds).\n"); 1101 exit(1); 1102 } 1103 1104 static void 1105 csh_setenv(const char *name, const char *value) 1106 { 1107 printf("setenv %s %s;\n", name, value); 1108 } 1109 1110 static void 1111 csh_unsetenv(const char *name) 1112 { 1113 printf("unsetenv %s;\n", name); 1114 } 1115 1116 static void 1117 sh_setenv(const char *name, const char *value) 1118 { 1119 printf("%s=%s; export %s;\n", name, value, name); 1120 } 1121 1122 static void 1123 sh_unsetenv(const char *name) 1124 { 1125 printf("unset %s;\n", name); 1126 } 1127 int 1128 main(int ac, char **av) 1129 { 1130 int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0; 1131 int sock, fd, ch, result, saved_errno; 1132 u_int nalloc; 1133 char *shell, *pidstr, *agentsocket = NULL; 1134 fd_set *readsetp = NULL, *writesetp = NULL; 1135 struct sockaddr_un sunaddr; 1136 struct rlimit rlim; 1137 extern int optind; 1138 extern char *optarg; 1139 pid_t pid; 1140 char pidstrbuf[1 + 3 * sizeof pid]; 1141 struct timeval *tvp = NULL; 1142 size_t len; 1143 void (*f_setenv)(const char *, const char *); 1144 void (*f_unsetenv)(const char *); 1145 1146 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 1147 sanitise_stdfd(); 1148 1149 /* drop */ 1150 setegid(getgid()); 1151 setgid(getgid()); 1152 1153 OpenSSL_add_all_algorithms(); 1154 1155 while ((ch = getopt(ac, av, "cdksa:t:")) != -1) { 1156 switch (ch) { 1157 case 'c': 1158 if (s_flag) 1159 usage(); 1160 c_flag++; 1161 break; 1162 case 'k': 1163 k_flag++; 1164 break; 1165 case 's': 1166 if (c_flag) 1167 usage(); 1168 s_flag++; 1169 break; 1170 case 'd': 1171 if (d_flag) 1172 usage(); 1173 d_flag++; 1174 break; 1175 case 'a': 1176 agentsocket = optarg; 1177 break; 1178 case 't': 1179 if ((lifetime = convtime(optarg)) == -1) { 1180 fprintf(stderr, "Invalid lifetime\n"); 1181 usage(); 1182 } 1183 break; 1184 default: 1185 usage(); 1186 } 1187 } 1188 ac -= optind; 1189 av += optind; 1190 1191 if (ac > 0 && (c_flag || k_flag || s_flag || d_flag)) 1192 usage(); 1193 1194 if (ac == 0 && !c_flag && !s_flag) { 1195 shell = getenv("SHELL"); 1196 if (shell != NULL && (len = strlen(shell)) > 2 && 1197 strncmp(shell + len - 3, "csh", 3) == 0) 1198 c_flag = 1; 1199 } 1200 if (c_flag) { 1201 f_setenv = csh_setenv; 1202 f_unsetenv = csh_unsetenv; 1203 } else { 1204 f_setenv = sh_setenv; 1205 f_unsetenv = sh_unsetenv; 1206 } 1207 if (k_flag) { 1208 const char *errstr = NULL; 1209 1210 pidstr = getenv(SSH_AGENTPID_ENV_NAME); 1211 if (pidstr == NULL) { 1212 fprintf(stderr, "%s not set, cannot kill agent\n", 1213 SSH_AGENTPID_ENV_NAME); 1214 exit(1); 1215 } 1216 pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr); 1217 if (errstr) { 1218 fprintf(stderr, 1219 "%s=\"%s\", which is not a good PID: %s\n", 1220 SSH_AGENTPID_ENV_NAME, pidstr, errstr); 1221 exit(1); 1222 } 1223 if (kill(pid, SIGTERM) == -1) { 1224 perror("kill"); 1225 exit(1); 1226 } 1227 (*f_unsetenv)(SSH_AUTHSOCKET_ENV_NAME); 1228 (*f_unsetenv)(SSH_AGENTPID_ENV_NAME); 1229 printf("echo Agent pid %ld killed;\n", (long)pid); 1230 exit(0); 1231 } 1232 parent_pid = getpid(); 1233 1234 if (agentsocket == NULL) { 1235 /* Create private directory for agent socket */ 1236 mktemp_proto(socket_dir, sizeof(socket_dir)); 1237 if (mkdtemp(socket_dir) == NULL) { 1238 perror("mkdtemp: private socket dir"); 1239 exit(1); 1240 } 1241 snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir, 1242 (long)parent_pid); 1243 } else { 1244 /* Try to use specified agent socket */ 1245 socket_dir[0] = '\0'; 1246 strlcpy(socket_name, agentsocket, sizeof socket_name); 1247 } 1248 1249 /* 1250 * Create socket early so it will exist before command gets run from 1251 * the parent. 1252 */ 1253 sock = socket(AF_UNIX, SOCK_STREAM, 0); 1254 if (sock < 0) { 1255 perror("socket"); 1256 *socket_name = '\0'; /* Don't unlink any existing file */ 1257 cleanup_exit(1); 1258 } 1259 memset(&sunaddr, 0, sizeof(sunaddr)); 1260 sunaddr.sun_family = AF_UNIX; 1261 strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path)); 1262 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) { 1263 perror("bind"); 1264 *socket_name = '\0'; /* Don't unlink any existing file */ 1265 cleanup_exit(1); 1266 } 1267 if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { 1268 perror("listen"); 1269 cleanup_exit(1); 1270 } 1271 1272 /* 1273 * Fork, and have the parent execute the command, if any, or present 1274 * the socket data. The child continues as the authentication agent. 1275 */ 1276 if (d_flag) { 1277 log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1); 1278 (*f_setenv)(SSH_AUTHSOCKET_ENV_NAME, socket_name); 1279 printf("echo Agent pid %ld;\n", (long)parent_pid); 1280 goto skip; 1281 } 1282 pid = fork(); 1283 if (pid == -1) { 1284 perror("fork"); 1285 cleanup_exit(1); 1286 } 1287 if (pid != 0) { /* Parent - execute the given command. */ 1288 close(sock); 1289 snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid); 1290 if (ac == 0) { 1291 (*f_setenv)(SSH_AUTHSOCKET_ENV_NAME, socket_name); 1292 (*f_setenv)(SSH_AGENTPID_ENV_NAME, pidstrbuf); 1293 printf("echo Agent pid %ld;\n", (long)pid); 1294 exit(0); 1295 } 1296 if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || 1297 setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { 1298 perror("setenv"); 1299 exit(1); 1300 } 1301 execvp(av[0], av); 1302 perror(av[0]); 1303 exit(1); 1304 } 1305 /* child */ 1306 log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0); 1307 1308 if (setsid() == -1) { 1309 error("setsid: %s", strerror(errno)); 1310 cleanup_exit(1); 1311 } 1312 1313 (void)chdir("/"); 1314 1315 if (sock != STDERR_FILENO + 1) { 1316 if (dup2(sock, STDERR_FILENO + 1) == -1) { 1317 error("dup2: %s", strerror(errno)); 1318 cleanup_exit(1); 1319 } 1320 close(sock); 1321 sock = STDERR_FILENO + 1; 1322 } 1323 #if defined(F_CLOSEM) 1324 if (fcntl(sock + 1, F_CLOSEM, 0) == -1) { 1325 error("fcntl F_CLOSEM: %s", strerror(errno)); 1326 cleanup_exit(1); 1327 } 1328 #else 1329 { 1330 int nfiles; 1331 #if defined(_SC_OPEN_MAX) 1332 nfiles = sysconf(_SC_OPEN_MAX); 1333 #elif defined(RLIMIT_NOFILE) 1334 if (getrlimit(RLIMIT_CORE, &rlim) < 0) { 1335 error("getrlimit RLIMIT_NOFILE: %s", strerror(errno)); 1336 cleanup_exit(1); 1337 } 1338 nfiles = rlim.rlim_cur; 1339 #elif defined(OPEN_MAX) 1340 nfiles = OPEN_MAX; 1341 #elif defined(NOFILE) 1342 nfiles = NOFILE; 1343 #else 1344 nfiles = 1024; 1345 #endif 1346 for (fd = sock + 1; fd < nfiles; fd++) 1347 close(fd); 1348 } 1349 #endif 1350 if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 1351 if (dup2(fd, STDIN_FILENO) == -1 || 1352 dup2(fd, STDOUT_FILENO) == -1 || 1353 dup2(fd, STDERR_FILENO) == -1) { 1354 error("dup2: %s", strerror(errno)); 1355 cleanup_exit(1); 1356 } 1357 if (fd > STDERR_FILENO) 1358 close(fd); 1359 } 1360 1361 /* deny core dumps, since memory contains unencrypted private keys */ 1362 rlim.rlim_cur = rlim.rlim_max = 0; 1363 if (setrlimit(RLIMIT_CORE, &rlim) < 0) { 1364 error("setrlimit RLIMIT_CORE: %s", strerror(errno)); 1365 cleanup_exit(1); 1366 } 1367 1368 skip: 1369 1370 #ifdef ENABLE_PKCS11 1371 pkcs11_init(0); 1372 #endif 1373 new_socket(AUTH_SOCKET, sock); 1374 if (ac > 0) 1375 parent_alive_interval = 10; 1376 idtab_init(); 1377 signal(SIGPIPE, SIG_IGN); 1378 signal(SIGINT, d_flag ? cleanup_handler : SIG_IGN); 1379 signal(SIGHUP, cleanup_handler); 1380 signal(SIGTERM, cleanup_handler); 1381 nalloc = 0; 1382 1383 while (1) { 1384 prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp); 1385 result = select(max_fd + 1, readsetp, writesetp, NULL, tvp); 1386 saved_errno = errno; 1387 if (parent_alive_interval != 0) 1388 check_parent_exists(); 1389 (void) reaper(); /* remove expired keys */ 1390 if (result < 0) { 1391 if (saved_errno == EINTR) 1392 continue; 1393 fatal("select: %s", strerror(saved_errno)); 1394 } else if (result > 0) 1395 after_select(readsetp, writesetp); 1396 } 1397 /* NOTREACHED */ 1398 } 1399