1 /* $OpenBSD: ldapclient.c,v 1.38 2017/01/20 12:39:36 benno Exp $ */ 2 3 /* 4 * Copyright (c) 2008 Alexander Schrijver <aschrijver@openbsd.org> 5 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/types.h> 21 #include <sys/queue.h> 22 #include <sys/socket.h> 23 #include <sys/tree.h> 24 25 #include <netinet/in.h> 26 #include <arpa/inet.h> 27 28 #include <netdb.h> 29 #include <errno.h> 30 #include <err.h> 31 #include <signal.h> 32 #include <event.h> 33 #include <fcntl.h> 34 #include <unistd.h> 35 #include <pwd.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 #include <limits.h> 40 41 #include "aldap.h" 42 #include "log.h" 43 #include "ypldap.h" 44 45 void client_sig_handler(int, short, void *); 46 void client_dispatch_dns(int, short, void *); 47 void client_dispatch_parent(int, short, void *); 48 void client_shutdown(void); 49 void client_connect(int, short, void *); 50 void client_configure(struct env *); 51 void client_periodic_update(int, short, void *); 52 int client_build_req(struct idm *, struct idm_req *, struct aldap_message *, 53 int, int); 54 int client_search_idm(struct env *, struct idm *, struct aldap *, 55 char **, char *, int, int, enum imsg_type); 56 int client_try_idm(struct env *, struct idm *); 57 int client_addr_init(struct idm *); 58 int client_addr_free(struct idm *); 59 60 struct aldap *client_aldap_open(struct ypldap_addr_list *); 61 62 /* 63 * dummy wrapper to provide aldap_init with its fd's. 64 */ 65 struct aldap * 66 client_aldap_open(struct ypldap_addr_list *addr) 67 { 68 int fd = -1; 69 struct ypldap_addr *p; 70 71 TAILQ_FOREACH(p, addr, next) { 72 char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; 73 struct sockaddr *sa = (struct sockaddr *)&p->ss; 74 75 if (getnameinfo(sa, SA_LEN(sa), hbuf, sizeof(hbuf), sbuf, 76 sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV)) 77 errx(1, "could not get numeric hostname"); 78 79 if ((fd = socket(sa->sa_family, SOCK_STREAM, 0)) < 0) 80 return NULL; 81 82 if (connect(fd, sa, SA_LEN(sa)) == 0) 83 break; 84 85 warn("connect to %s port %s (%s) failed", hbuf, sbuf, "tcp"); 86 close(fd); 87 } 88 89 if (fd == -1) 90 return NULL; 91 92 return aldap_init(fd); 93 } 94 95 int 96 client_addr_init(struct idm *idm) 97 { 98 struct sockaddr_in *sa_in; 99 struct sockaddr_in6 *sa_in6; 100 struct ypldap_addr *h; 101 102 TAILQ_FOREACH(h, &idm->idm_addr, next) { 103 switch (h->ss.ss_family) { 104 case AF_INET: 105 sa_in = (struct sockaddr_in *)&h->ss; 106 if (ntohs(sa_in->sin_port) == 0) 107 sa_in->sin_port = htons(LDAP_PORT); 108 idm->idm_state = STATE_DNS_DONE; 109 break; 110 case AF_INET6: 111 sa_in6 = (struct sockaddr_in6 *)&h->ss; 112 if (ntohs(sa_in6->sin6_port) == 0) 113 sa_in6->sin6_port = htons(LDAP_PORT); 114 idm->idm_state = STATE_DNS_DONE; 115 break; 116 default: 117 fatalx("king bula sez: wrong AF in client_addr_init"); 118 /* not reached */ 119 } 120 } 121 122 return (0); 123 } 124 125 int 126 client_addr_free(struct idm *idm) 127 { 128 struct ypldap_addr *h; 129 130 while (!TAILQ_EMPTY(&idm->idm_addr)) { 131 h = TAILQ_FIRST(&idm->idm_addr); 132 TAILQ_REMOVE(&idm->idm_addr, h, next); 133 free(h); 134 } 135 136 return (0); 137 } 138 139 void 140 client_sig_handler(int sig, short event, void *p) 141 { 142 switch (sig) { 143 case SIGINT: 144 case SIGTERM: 145 client_shutdown(); 146 break; 147 default: 148 fatalx("unexpected signal"); 149 } 150 } 151 152 void 153 client_dispatch_dns(int fd, short events, void *p) 154 { 155 struct imsg imsg; 156 u_int16_t dlen; 157 u_char *data; 158 struct ypldap_addr *h; 159 int n, wait_cnt = 0; 160 struct idm *idm; 161 int shut = 0; 162 163 struct env *env = p; 164 struct imsgev *iev = env->sc_iev_dns; 165 struct imsgbuf *ibuf = &iev->ibuf; 166 167 if ((events & (EV_READ | EV_WRITE)) == 0) 168 fatalx("unknown event"); 169 170 if (events & EV_READ) { 171 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN) 172 fatal("imsg_read error"); 173 if (n == 0) 174 shut = 1; 175 } 176 if (events & EV_WRITE) { 177 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN) 178 fatal("msgbuf_write"); 179 if (n == 0) 180 shut = 1; 181 goto done; 182 } 183 184 for (;;) { 185 if ((n = imsg_get(ibuf, &imsg)) == -1) 186 fatal("client_dispatch_dns: imsg_get error"); 187 if (n == 0) 188 break; 189 190 switch (imsg.hdr.type) { 191 case IMSG_HOST_DNS: 192 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) 193 if (idm->idm_id == imsg.hdr.peerid) 194 break; 195 if (idm == NULL) { 196 log_warnx("IMSG_HOST_DNS with invalid peerID"); 197 break; 198 } 199 if (!TAILQ_EMPTY(&idm->idm_addr)) { 200 log_warnx("IMSG_HOST_DNS but addrs set!"); 201 break; 202 } 203 204 dlen = imsg.hdr.len - IMSG_HEADER_SIZE; 205 if (dlen == 0) { /* no data -> temp error */ 206 idm->idm_state = STATE_DNS_TEMPFAIL; 207 break; 208 } 209 210 data = (u_char *)imsg.data; 211 while (dlen >= sizeof(struct sockaddr_storage)) { 212 if ((h = calloc(1, sizeof(*h))) == NULL) 213 fatal(NULL); 214 memcpy(&h->ss, data, sizeof(h->ss)); 215 TAILQ_INSERT_HEAD(&idm->idm_addr, h, next); 216 217 data += sizeof(h->ss); 218 dlen -= sizeof(h->ss); 219 } 220 if (dlen != 0) 221 fatalx("IMSG_HOST_DNS: dlen != 0"); 222 223 client_addr_init(idm); 224 225 break; 226 default: 227 break; 228 } 229 imsg_free(&imsg); 230 } 231 232 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 233 if (client_try_idm(env, idm) == -1) 234 idm->idm_state = STATE_LDAP_FAIL; 235 236 if (idm->idm_state < STATE_LDAP_DONE) 237 wait_cnt++; 238 } 239 if (wait_cnt == 0) 240 imsg_compose_event(env->sc_iev, IMSG_END_UPDATE, 0, 0, -1, 241 NULL, 0); 242 243 done: 244 if (!shut) 245 imsg_event_add(iev); 246 else { 247 /* this pipe is dead, so remove the event handler */ 248 event_del(&iev->ev); 249 event_loopexit(NULL); 250 } 251 } 252 253 void 254 client_dispatch_parent(int fd, short events, void *p) 255 { 256 int n; 257 int shut = 0; 258 struct imsg imsg; 259 struct env *env = p; 260 struct imsgev *iev = env->sc_iev; 261 struct imsgbuf *ibuf = &iev->ibuf; 262 263 if ((events & (EV_READ | EV_WRITE)) == 0) 264 fatalx("unknown event"); 265 266 if (events & EV_READ) { 267 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN) 268 fatal("imsg_read error"); 269 if (n == 0) 270 shut = 1; 271 } 272 if (events & EV_WRITE) { 273 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN) 274 fatal("msgbuf_write"); 275 if (n == 0) 276 shut = 1; 277 goto done; 278 } 279 280 for (;;) { 281 if ((n = imsg_get(ibuf, &imsg)) == -1) 282 fatal("client_dispatch_parent: imsg_get error"); 283 if (n == 0) 284 break; 285 286 switch (imsg.hdr.type) { 287 case IMSG_CONF_START: { 288 struct env params; 289 290 if (env->sc_flags & F_CONFIGURING) { 291 log_warnx("configuration already in progress"); 292 break; 293 } 294 memcpy(¶ms, imsg.data, sizeof(params)); 295 log_debug("configuration starting"); 296 env->sc_flags |= F_CONFIGURING; 297 purge_config(env); 298 memcpy(&env->sc_conf_tv, ¶ms.sc_conf_tv, 299 sizeof(env->sc_conf_tv)); 300 env->sc_flags |= params.sc_flags; 301 break; 302 } 303 case IMSG_CONF_IDM: { 304 struct idm *idm; 305 306 if (!(env->sc_flags & F_CONFIGURING)) 307 break; 308 if ((idm = calloc(1, sizeof(*idm))) == NULL) 309 fatal(NULL); 310 memcpy(idm, imsg.data, sizeof(*idm)); 311 idm->idm_env = env; 312 TAILQ_INSERT_TAIL(&env->sc_idms, idm, idm_entry); 313 break; 314 } 315 case IMSG_CONF_END: 316 env->sc_flags &= ~F_CONFIGURING; 317 log_debug("applying configuration"); 318 client_configure(env); 319 break; 320 default: 321 log_debug("client_dispatch_parent: unexpect imsg %d", 322 imsg.hdr.type); 323 324 break; 325 } 326 imsg_free(&imsg); 327 } 328 329 done: 330 if (!shut) 331 imsg_event_add(iev); 332 else { 333 /* this pipe is dead, so remove the event handler */ 334 event_del(&iev->ev); 335 event_loopexit(NULL); 336 } 337 } 338 339 void 340 client_shutdown(void) 341 { 342 log_info("ldap client exiting"); 343 _exit(0); 344 } 345 346 pid_t 347 ldapclient(int pipe_main2client[2]) 348 { 349 pid_t pid, dns_pid; 350 int pipe_dns[2]; 351 struct passwd *pw; 352 struct event ev_sigint; 353 struct event ev_sigterm; 354 struct env env; 355 356 switch (pid = fork()) { 357 case -1: 358 fatal("cannot fork"); 359 break; 360 case 0: 361 break; 362 default: 363 return (pid); 364 } 365 366 memset(&env, 0, sizeof(env)); 367 TAILQ_INIT(&env.sc_idms); 368 369 if ((pw = getpwnam(YPLDAP_USER)) == NULL) 370 fatal("getpwnam"); 371 372 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_dns) == -1) 373 fatal("socketpair"); 374 dns_pid = ypldap_dns(pipe_dns, pw); 375 close(pipe_dns[1]); 376 377 #ifndef DEBUG 378 if (chroot(pw->pw_dir) == -1) 379 fatal("chroot"); 380 if (chdir("/") == -1) 381 fatal("chdir"); 382 #else 383 #warning disabling chrooting in DEBUG mode 384 #endif 385 setproctitle("ldap client"); 386 ypldap_process = PROC_CLIENT; 387 log_procname = log_procnames[ypldap_process]; 388 389 #ifndef DEBUG 390 if (setgroups(1, &pw->pw_gid) || 391 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) || 392 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) 393 fatal("cannot drop privileges"); 394 #else 395 #warning disabling privilege revocation in DEBUG mode 396 #endif 397 398 if (pledge("stdio inet", NULL) == -1) 399 fatal("pledge"); 400 401 event_init(); 402 signal(SIGPIPE, SIG_IGN); 403 signal_set(&ev_sigint, SIGINT, client_sig_handler, NULL); 404 signal_set(&ev_sigterm, SIGTERM, client_sig_handler, NULL); 405 signal_add(&ev_sigint, NULL); 406 signal_add(&ev_sigterm, NULL); 407 408 close(pipe_main2client[0]); 409 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL) 410 fatal(NULL); 411 if ((env.sc_iev_dns = calloc(1, sizeof(*env.sc_iev_dns))) == NULL) 412 fatal(NULL); 413 414 env.sc_iev->events = EV_READ; 415 env.sc_iev->data = &env; 416 imsg_init(&env.sc_iev->ibuf, pipe_main2client[1]); 417 env.sc_iev->handler = client_dispatch_parent; 418 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events, 419 env.sc_iev->handler, &env); 420 event_add(&env.sc_iev->ev, NULL); 421 422 env.sc_iev_dns->events = EV_READ; 423 env.sc_iev_dns->data = &env; 424 imsg_init(&env.sc_iev_dns->ibuf, pipe_dns[0]); 425 env.sc_iev_dns->handler = client_dispatch_dns; 426 event_set(&env.sc_iev_dns->ev, env.sc_iev_dns->ibuf.fd, 427 env.sc_iev_dns->events, env.sc_iev_dns->handler, &env); 428 event_add(&env.sc_iev_dns->ev, NULL); 429 430 event_dispatch(); 431 client_shutdown(); 432 433 return (0); 434 435 } 436 437 int 438 client_build_req(struct idm *idm, struct idm_req *ir, struct aldap_message *m, 439 int min_attr, int max_attr) 440 { 441 char **ldap_attrs; 442 int i, k; 443 444 memset(ir, 0, sizeof(*ir)); 445 for (i = min_attr; i < max_attr; i++) { 446 if (idm->idm_flags & F_FIXED_ATTR(i)) { 447 if (strlcat(ir->ir_line, idm->idm_attrs[i], 448 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 449 /* 450 * entry yields a line > 1024, trash it. 451 */ 452 return (-1); 453 454 if (i == ATTR_UID) { 455 ir->ir_key.ik_uid = strtonum( 456 idm->idm_attrs[i], 0, 457 UID_MAX, NULL); 458 } else if (i == ATTR_GR_GID) { 459 ir->ir_key.ik_gid = strtonum( 460 idm->idm_attrs[i], 0, 461 GID_MAX, NULL); 462 } 463 } else if (idm->idm_list & F_LIST(i)) { 464 aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs); 465 for (k = 0; k >= 0 && ldap_attrs && ldap_attrs[k] != NULL; k++) { 466 /* XXX: Fail when attributes have illegal characters e.g. ',' */ 467 if (strlcat(ir->ir_line, ldap_attrs[k], 468 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 469 continue; 470 if (ldap_attrs[k+1] != NULL) 471 if (strlcat(ir->ir_line, ",", 472 sizeof(ir->ir_line)) 473 >= sizeof(ir->ir_line)) { 474 aldap_free_attr(ldap_attrs); 475 return (-1); 476 } 477 } 478 aldap_free_attr(ldap_attrs); 479 } else { 480 if (aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs) == -1) 481 return (-1); 482 if (ldap_attrs[0] == NULL) 483 return (-1); 484 if (strlcat(ir->ir_line, ldap_attrs[0], 485 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) { 486 aldap_free_attr(ldap_attrs); 487 return (-1); 488 } 489 if (i == ATTR_UID) { 490 ir->ir_key.ik_uid = strtonum( 491 ldap_attrs[0], 0, UID_MAX, NULL); 492 } else if (i == ATTR_GR_GID) { 493 ir->ir_key.ik_uid = strtonum( 494 ldap_attrs[0], 0, GID_MAX, NULL); 495 } 496 aldap_free_attr(ldap_attrs); 497 } 498 499 if (i + 1 != max_attr) 500 if (strlcat(ir->ir_line, ":", 501 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 502 return (-1); 503 } 504 505 return (0); 506 } 507 508 int 509 client_search_idm(struct env *env, struct idm *idm, struct aldap *al, 510 char **attrs, char *filter, int min_attr, int max_attr, 511 enum imsg_type type) 512 { 513 struct idm_req ir; 514 struct aldap_message *m; 515 struct aldap_page_control *pg = NULL; 516 const char *errstr; 517 char *dn; 518 519 dn = idm->idm_basedn; 520 if (type == IMSG_GRP_ENTRY && idm->idm_groupdn[0] != '\0') 521 dn = idm->idm_groupdn; 522 523 do { 524 if (aldap_search(al, dn, LDAP_SCOPE_SUBTREE, 525 filter, attrs, 0, 0, 0, pg) == -1) { 526 aldap_get_errno(al, &errstr); 527 log_debug("%s", errstr); 528 return (-1); 529 } 530 531 if (pg != NULL) { 532 aldap_freepage(pg); 533 pg = NULL; 534 } 535 536 while ((m = aldap_parse(al)) != NULL) { 537 if (al->msgid != m->msgid) { 538 goto fail; 539 } 540 541 if (m->message_type == LDAP_RES_SEARCH_RESULT) { 542 if (m->page != NULL && m->page->cookie_len != 0) 543 pg = m->page; 544 else 545 pg = NULL; 546 547 aldap_freemsg(m); 548 break; 549 } 550 551 if (m->message_type != LDAP_RES_SEARCH_ENTRY) { 552 goto fail; 553 } 554 555 if (client_build_req(idm, &ir, m, min_attr, max_attr) == 0) 556 imsg_compose_event(env->sc_iev, type, 0, 0, -1, 557 &ir, sizeof(ir)); 558 559 aldap_freemsg(m); 560 } 561 } while (pg != NULL); 562 563 return (0); 564 565 fail: 566 aldap_freemsg(m); 567 if (pg != NULL) { 568 aldap_freepage(pg); 569 } 570 571 return (-1); 572 } 573 574 int 575 client_try_idm(struct env *env, struct idm *idm) 576 { 577 const char *where; 578 char *attrs[ATTR_MAX+1]; 579 int i, j; 580 struct aldap_message *m; 581 struct aldap *al; 582 583 where = "connect"; 584 if ((al = client_aldap_open(&idm->idm_addr)) == NULL) 585 return (-1); 586 587 if (idm->idm_flags & F_NEEDAUTH) { 588 where = "binding"; 589 if (aldap_bind(al, idm->idm_binddn, idm->idm_bindcred) == -1) 590 goto bad; 591 592 where = "parsing"; 593 if ((m = aldap_parse(al)) == NULL) 594 goto bad; 595 where = "verifying msgid"; 596 if (al->msgid != m->msgid) { 597 aldap_freemsg(m); 598 goto bad; 599 } 600 aldap_freemsg(m); 601 } 602 603 memset(attrs, 0, sizeof(attrs)); 604 for (i = 0, j = 0; i < ATTR_MAX; i++) { 605 if (idm->idm_flags & F_FIXED_ATTR(i)) 606 continue; 607 attrs[j++] = idm->idm_attrs[i]; 608 } 609 attrs[j] = NULL; 610 611 /* 612 * build password line. 613 */ 614 where = "search"; 615 log_debug("searching password entries"); 616 if (client_search_idm(env, idm, al, attrs, 617 idm->idm_filters[FILTER_USER], 0, ATTR_MAX, IMSG_PW_ENTRY) == -1) 618 goto bad; 619 620 memset(attrs, 0, sizeof(attrs)); 621 for (i = ATTR_GR_MIN, j = 0; i < ATTR_GR_MAX; i++) { 622 if (idm->idm_flags & F_FIXED_ATTR(i)) 623 continue; 624 attrs[j++] = idm->idm_attrs[i]; 625 } 626 attrs[j] = NULL; 627 628 /* 629 * build group line. 630 */ 631 where = "search"; 632 log_debug("searching group entries"); 633 if (client_search_idm(env, idm, al, attrs, 634 idm->idm_filters[FILTER_GROUP], ATTR_GR_MIN, ATTR_GR_MAX, 635 IMSG_GRP_ENTRY) == -1) 636 goto bad; 637 638 aldap_close(al); 639 640 idm->idm_state = STATE_LDAP_DONE; 641 642 return (0); 643 bad: 644 aldap_close(al); 645 log_debug("directory %s errored out in %s", idm->idm_name, where); 646 return (-1); 647 } 648 649 void 650 client_periodic_update(int fd, short event, void *p) 651 { 652 struct env *env = p; 653 654 struct idm *idm; 655 int fail_cnt = 0; 656 657 /* If LDAP isn't finished, notify the master process to trash the 658 * update. */ 659 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 660 if (idm->idm_state < STATE_LDAP_DONE) 661 fail_cnt++; 662 663 idm->idm_state = STATE_NONE; 664 665 client_addr_free(idm); 666 } 667 if (fail_cnt > 0) { 668 log_debug("trash the update"); 669 imsg_compose_event(env->sc_iev, IMSG_TRASH_UPDATE, 0, 0, -1, 670 NULL, 0); 671 } 672 673 client_configure(env); 674 } 675 676 void 677 client_configure(struct env *env) 678 { 679 struct timeval tv; 680 struct idm *idm; 681 u_int16_t dlen; 682 683 log_debug("connecting to directories"); 684 685 imsg_compose_event(env->sc_iev, IMSG_START_UPDATE, 0, 0, -1, NULL, 0); 686 687 /* Start the DNS lookups */ 688 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 689 dlen = strlen(idm->idm_name) + 1; 690 imsg_compose_event(env->sc_iev_dns, IMSG_HOST_DNS, idm->idm_id, 691 0, -1, idm->idm_name, dlen); 692 } 693 694 tv.tv_sec = env->sc_conf_tv.tv_sec; 695 tv.tv_usec = env->sc_conf_tv.tv_usec; 696 evtimer_set(&env->sc_conf_ev, client_periodic_update, env); 697 evtimer_add(&env->sc_conf_ev, &tv); 698 } 699