1 /* $OpenBSD: ldapclient.c,v 1.31 2014/11/16 23:24:44 tedu 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/param.h> 22 #include <sys/queue.h> 23 #include <sys/socket.h> 24 #include <sys/tree.h> 25 26 #include <netinet/in.h> 27 #include <arpa/inet.h> 28 29 #include <netdb.h> 30 #include <errno.h> 31 #include <err.h> 32 #include <event.h> 33 #include <fcntl.h> 34 #include <unistd.h> 35 #include <pwd.h> 36 #include <signal.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 41 #include "aldap.h" 42 #include "ypldap.h" 43 44 void client_sig_handler(int, short, void *); 45 void client_dispatch_dns(int, short, void *); 46 void client_dispatch_parent(int, short, void *); 47 void client_shutdown(void); 48 void client_connect(int, short, void *); 49 void client_configure(struct env *); 50 void client_periodic_update(int, short, void *); 51 int client_build_req(struct idm *, struct idm_req *, struct aldap_message *, 52 int, int); 53 int client_search_idm(struct env *, struct idm *, struct aldap *, 54 char **, char *, int, int, enum imsg_type); 55 int client_try_idm(struct env *, struct idm *); 56 int client_addr_init(struct idm *); 57 int client_addr_free(struct idm *); 58 59 struct aldap *client_aldap_open(struct ypldap_addr_list *); 60 61 /* 62 * dummy wrapper to provide aldap_init with its fd's. 63 */ 64 struct aldap * client_aldap_open(struct ypldap_addr_list * addr)65 client_aldap_open(struct ypldap_addr_list *addr) 66 { 67 int fd = -1; 68 struct ypldap_addr *p; 69 70 TAILQ_FOREACH(p, addr, next) { 71 char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; 72 struct sockaddr *sa = (struct sockaddr *)&p->ss; 73 74 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), sbuf, 75 sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV)) 76 errx(1, "could not get numeric hostname"); 77 78 if ((fd = socket(sa->sa_family, SOCK_STREAM, 0)) < 0) 79 return NULL; 80 81 if (connect(fd, sa, sa->sa_len) == 0) 82 break; 83 84 warn("connect to %s port %s (%s) failed", hbuf, sbuf, "tcp"); 85 close(fd); 86 } 87 88 if (fd == -1) 89 return NULL; 90 91 return aldap_init(fd); 92 } 93 94 int client_addr_init(struct idm * idm)95 client_addr_init(struct idm *idm) 96 { 97 struct sockaddr_in *sa_in; 98 struct sockaddr_in6 *sa_in6; 99 struct ypldap_addr *h; 100 101 TAILQ_FOREACH(h, &idm->idm_addr, next) { 102 switch (h->ss.ss_family) { 103 case AF_INET: 104 sa_in = (struct sockaddr_in *)&h->ss; 105 if (ntohs(sa_in->sin_port) == 0) 106 sa_in->sin_port = htons(LDAP_PORT); 107 idm->idm_state = STATE_DNS_DONE; 108 break; 109 case AF_INET6: 110 sa_in6 = (struct sockaddr_in6 *)&h->ss; 111 if (ntohs(sa_in6->sin6_port) == 0) 112 sa_in6->sin6_port = htons(LDAP_PORT); 113 idm->idm_state = STATE_DNS_DONE; 114 break; 115 default: 116 fatalx("king bula sez: wrong AF in client_addr_init"); 117 /* not reached */ 118 } 119 } 120 121 return (0); 122 } 123 124 int client_addr_free(struct idm * idm)125 client_addr_free(struct idm *idm) 126 { 127 struct ypldap_addr *h; 128 129 while (!TAILQ_EMPTY(&idm->idm_addr)) { 130 h = TAILQ_FIRST(&idm->idm_addr); 131 TAILQ_REMOVE(&idm->idm_addr, h, next); 132 free(h); 133 } 134 135 return (0); 136 } 137 138 void client_sig_handler(int sig,short event,void * p)139 client_sig_handler(int sig, short event, void *p) 140 { 141 switch (sig) { 142 case SIGINT: 143 case SIGTERM: 144 client_shutdown(); 145 break; 146 default: 147 fatalx("unexpected signal"); 148 } 149 } 150 151 void client_dispatch_dns(int fd,short events,void * p)152 client_dispatch_dns(int fd, short events, void *p) 153 { 154 struct imsg imsg; 155 u_int16_t dlen; 156 u_char *data; 157 struct ypldap_addr *h; 158 int n, wait_cnt = 0; 159 struct idm *idm; 160 int shut = 0; 161 162 struct env *env = p; 163 struct imsgev *iev = env->sc_iev_dns; 164 struct imsgbuf *ibuf = &iev->ibuf; 165 166 if ((events & (EV_READ | EV_WRITE)) == 0) 167 fatalx("unknown event"); 168 169 if (events & EV_READ) { 170 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN) 171 fatal("imsg_read error"); 172 if (n == 0) 173 shut = 1; 174 } 175 if (events & EV_WRITE) { 176 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN) 177 fatal("msgbuf_write"); 178 if (n == 0) 179 shut = 1; 180 goto done; 181 } 182 183 for (;;) { 184 if ((n = imsg_get(ibuf, &imsg)) == -1) 185 fatal("client_dispatch_dns: imsg_get error"); 186 if (n == 0) 187 break; 188 189 switch (imsg.hdr.type) { 190 case IMSG_HOST_DNS: 191 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) 192 if (idm->idm_id == imsg.hdr.peerid) 193 break; 194 if (idm == NULL) { 195 log_warnx("IMSG_HOST_DNS with invalid peerID"); 196 break; 197 } 198 if (!TAILQ_EMPTY(&idm->idm_addr)) { 199 log_warnx("IMSG_HOST_DNS but addrs set!"); 200 break; 201 } 202 203 dlen = imsg.hdr.len - IMSG_HEADER_SIZE; 204 if (dlen == 0) { /* no data -> temp error */ 205 idm->idm_state = STATE_DNS_TEMPFAIL; 206 break; 207 } 208 209 data = (u_char *)imsg.data; 210 while (dlen >= sizeof(struct sockaddr_storage)) { 211 if ((h = calloc(1, sizeof(*h))) == NULL) 212 fatal(NULL); 213 memcpy(&h->ss, data, sizeof(h->ss)); 214 TAILQ_INSERT_HEAD(&idm->idm_addr, h, next); 215 216 data += sizeof(h->ss); 217 dlen -= sizeof(h->ss); 218 } 219 if (dlen != 0) 220 fatalx("IMSG_HOST_DNS: dlen != 0"); 221 222 client_addr_init(idm); 223 224 break; 225 default: 226 break; 227 } 228 imsg_free(&imsg); 229 } 230 231 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 232 if (client_try_idm(env, idm) == -1) 233 idm->idm_state = STATE_LDAP_FAIL; 234 235 if (idm->idm_state < STATE_LDAP_DONE) 236 wait_cnt++; 237 } 238 if (wait_cnt == 0) 239 imsg_compose_event(env->sc_iev, IMSG_END_UPDATE, 0, 0, -1, 240 NULL, 0); 241 242 done: 243 if (!shut) 244 imsg_event_add(iev); 245 else { 246 /* this pipe is dead, so remove the event handler */ 247 event_del(&iev->ev); 248 event_loopexit(NULL); 249 } 250 } 251 252 void client_dispatch_parent(int fd,short events,void * p)253 client_dispatch_parent(int fd, short events, void *p) 254 { 255 int n; 256 int shut = 0; 257 struct imsg imsg; 258 struct env *env = p; 259 struct imsgev *iev = env->sc_iev; 260 struct imsgbuf *ibuf = &iev->ibuf; 261 262 if ((events & (EV_READ | EV_WRITE)) == 0) 263 fatalx("unknown event"); 264 265 if (events & EV_READ) { 266 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN) 267 fatal("imsg_read error"); 268 if (n == 0) 269 shut = 1; 270 } 271 if (events & EV_WRITE) { 272 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN) 273 fatal("msgbuf_write"); 274 if (n == 0) 275 shut = 1; 276 goto done; 277 } 278 279 for (;;) { 280 if ((n = imsg_get(ibuf, &imsg)) == -1) 281 fatal("client_dispatch_parent: imsg_get error"); 282 if (n == 0) 283 break; 284 285 switch (imsg.hdr.type) { 286 case IMSG_CONF_START: { 287 struct env params; 288 289 if (env->sc_flags & F_CONFIGURING) { 290 log_warnx("configuration already in progress"); 291 break; 292 } 293 memcpy(¶ms, imsg.data, sizeof(params)); 294 log_debug("configuration starting"); 295 env->sc_flags |= F_CONFIGURING; 296 purge_config(env); 297 memcpy(&env->sc_conf_tv, ¶ms.sc_conf_tv, 298 sizeof(env->sc_conf_tv)); 299 env->sc_flags |= params.sc_flags; 300 break; 301 } 302 case IMSG_CONF_IDM: { 303 struct idm *idm; 304 305 if (!(env->sc_flags & F_CONFIGURING)) 306 break; 307 if ((idm = calloc(1, sizeof(*idm))) == NULL) 308 fatal(NULL); 309 memcpy(idm, imsg.data, sizeof(*idm)); 310 idm->idm_env = env; 311 TAILQ_INSERT_TAIL(&env->sc_idms, idm, idm_entry); 312 break; 313 } 314 case IMSG_CONF_END: 315 env->sc_flags &= ~F_CONFIGURING; 316 log_debug("applying configuration"); 317 client_configure(env); 318 break; 319 default: 320 log_debug("client_dispatch_parent: unexpect imsg %d", 321 imsg.hdr.type); 322 323 break; 324 } 325 imsg_free(&imsg); 326 } 327 328 done: 329 if (!shut) 330 imsg_event_add(iev); 331 else { 332 /* this pipe is dead, so remove the event handler */ 333 event_del(&iev->ev); 334 event_loopexit(NULL); 335 } 336 } 337 338 void client_shutdown(void)339 client_shutdown(void) 340 { 341 log_info("ldap client exiting"); 342 _exit(0); 343 } 344 345 pid_t ldapclient(int pipe_main2client[2])346 ldapclient(int pipe_main2client[2]) 347 { 348 pid_t pid; 349 int pipe_dns[2]; 350 struct passwd *pw; 351 struct event ev_sigint; 352 struct event ev_sigterm; 353 struct env env; 354 355 switch (pid = fork()) { 356 case -1: 357 fatal("cannot fork"); 358 break; 359 case 0: 360 break; 361 default: 362 return (pid); 363 } 364 365 memset(&env, 0, sizeof(env)); 366 TAILQ_INIT(&env.sc_idms); 367 368 if ((pw = getpwnam(YPLDAP_USER)) == NULL) 369 fatal("getpwnam"); 370 371 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_dns) == -1) 372 fatal("socketpair"); 373 ypldap_dns(pipe_dns, pw); 374 close(pipe_dns[1]); 375 376 #ifndef DEBUG 377 if (chroot(pw->pw_dir) == -1) 378 fatal("chroot"); 379 if (chdir("/") == -1) 380 fatal("chdir"); 381 #else 382 #warning disabling chrooting in DEBUG mode 383 #endif 384 setproctitle("ldap client"); 385 ypldap_process = PROC_CLIENT; 386 387 #ifndef DEBUG 388 if (setgroups(1, &pw->pw_gid) || 389 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) || 390 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) 391 fatal("cannot drop privileges"); 392 #else 393 #warning disabling privilege revocation in DEBUG mode 394 #endif 395 396 event_init(); 397 signal(SIGPIPE, SIG_IGN); 398 signal_set(&ev_sigint, SIGINT, client_sig_handler, NULL); 399 signal_set(&ev_sigterm, SIGTERM, client_sig_handler, NULL); 400 signal_add(&ev_sigint, NULL); 401 signal_add(&ev_sigterm, NULL); 402 403 close(pipe_main2client[0]); 404 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL) 405 fatal(NULL); 406 if ((env.sc_iev_dns = calloc(1, sizeof(*env.sc_iev_dns))) == NULL) 407 fatal(NULL); 408 409 env.sc_iev->events = EV_READ; 410 env.sc_iev->data = &env; 411 imsg_init(&env.sc_iev->ibuf, pipe_main2client[1]); 412 env.sc_iev->handler = client_dispatch_parent; 413 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events, 414 env.sc_iev->handler, &env); 415 event_add(&env.sc_iev->ev, NULL); 416 417 env.sc_iev_dns->events = EV_READ; 418 env.sc_iev_dns->data = &env; 419 imsg_init(&env.sc_iev_dns->ibuf, pipe_dns[0]); 420 env.sc_iev_dns->handler = client_dispatch_dns; 421 event_set(&env.sc_iev_dns->ev, env.sc_iev_dns->ibuf.fd, 422 env.sc_iev_dns->events, env.sc_iev_dns->handler, &env); 423 event_add(&env.sc_iev_dns->ev, NULL); 424 425 event_dispatch(); 426 client_shutdown(); 427 428 return (0); 429 430 } 431 432 int client_build_req(struct idm * idm,struct idm_req * ir,struct aldap_message * m,int min_attr,int max_attr)433 client_build_req(struct idm *idm, struct idm_req *ir, struct aldap_message *m, 434 int min_attr, int max_attr) 435 { 436 char **ldap_attrs; 437 int i, k; 438 439 memset(ir, 0, sizeof(*ir)); 440 for (i = min_attr; i < max_attr; i++) { 441 if (idm->idm_flags & F_FIXED_ATTR(i)) { 442 if (strlcat(ir->ir_line, idm->idm_attrs[i], 443 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 444 /* 445 * entry yields a line > 1024, trash it. 446 */ 447 return (-1); 448 449 if (i == ATTR_UID) { 450 ir->ir_key.ik_uid = strtonum( 451 idm->idm_attrs[i], 0, 452 UID_MAX, NULL); 453 } else if (i == ATTR_GR_GID) { 454 ir->ir_key.ik_gid = strtonum( 455 idm->idm_attrs[i], 0, 456 GID_MAX, NULL); 457 } 458 } else if (idm->idm_list & F_LIST(i)) { 459 aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs); 460 for (k = 0; k >= 0 && ldap_attrs && ldap_attrs[k] != NULL; k++) { 461 /* XXX: Fail when attributes have illegal characters e.g. ',' */ 462 if (strlcat(ir->ir_line, ldap_attrs[k], 463 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 464 continue; 465 if (ldap_attrs[k+1] != NULL) 466 if (strlcat(ir->ir_line, ",", 467 sizeof(ir->ir_line)) 468 >= sizeof(ir->ir_line)) { 469 aldap_free_attr(ldap_attrs); 470 return (-1); 471 } 472 } 473 aldap_free_attr(ldap_attrs); 474 } else { 475 if (aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs) == -1) 476 return (-1); 477 if (strlcat(ir->ir_line, ldap_attrs[0], 478 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) { 479 aldap_free_attr(ldap_attrs); 480 return (-1); 481 } 482 if (i == ATTR_UID) { 483 ir->ir_key.ik_uid = strtonum( 484 ldap_attrs[0], 0, UID_MAX, NULL); 485 } else if (i == ATTR_GR_GID) { 486 ir->ir_key.ik_uid = strtonum( 487 ldap_attrs[0], 0, GID_MAX, NULL); 488 } 489 aldap_free_attr(ldap_attrs); 490 } 491 492 if (i + 1 != max_attr) 493 if (strlcat(ir->ir_line, ":", 494 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 495 return (-1); 496 } 497 498 return (0); 499 } 500 501 int client_search_idm(struct env * env,struct idm * idm,struct aldap * al,char ** attrs,char * filter,int min_attr,int max_attr,enum imsg_type type)502 client_search_idm(struct env *env, struct idm *idm, struct aldap *al, 503 char **attrs, char *filter, int min_attr, int max_attr, 504 enum imsg_type type) 505 { 506 struct idm_req ir; 507 struct aldap_message *m; 508 struct aldap_page_control *pg = NULL; 509 const char *errstr; 510 char *dn; 511 512 dn = idm->idm_basedn; 513 if (type == IMSG_GRP_ENTRY && idm->idm_groupdn[0] != '\0') 514 dn = idm->idm_groupdn; 515 516 do { 517 if (aldap_search(al, dn, LDAP_SCOPE_SUBTREE, 518 filter, attrs, 0, 0, 0, pg) == -1) { 519 aldap_get_errno(al, &errstr); 520 log_debug("%s", errstr); 521 return (-1); 522 } 523 524 if (pg != NULL) { 525 aldap_freepage(pg); 526 pg = NULL; 527 } 528 529 while ((m = aldap_parse(al)) != NULL) { 530 if (al->msgid != m->msgid) { 531 goto fail; 532 } 533 534 if (m->message_type == LDAP_RES_SEARCH_RESULT) { 535 if (m->page != NULL && m->page->cookie_len != 0) 536 pg = m->page; 537 else 538 pg = NULL; 539 540 aldap_freemsg(m); 541 break; 542 } 543 544 if (m->message_type != LDAP_RES_SEARCH_ENTRY) { 545 goto fail; 546 } 547 548 if (client_build_req(idm, &ir, m, min_attr, max_attr) == 0) 549 imsg_compose_event(env->sc_iev, type, 0, 0, -1, 550 &ir, sizeof(ir)); 551 552 aldap_freemsg(m); 553 } 554 } while (pg != NULL); 555 556 return (0); 557 558 fail: 559 aldap_freemsg(m); 560 if (pg != NULL) { 561 aldap_freepage(pg); 562 } 563 564 return (-1); 565 } 566 567 int client_try_idm(struct env * env,struct idm * idm)568 client_try_idm(struct env *env, struct idm *idm) 569 { 570 const char *where; 571 char *attrs[ATTR_MAX+1]; 572 int i, j; 573 struct aldap_message *m; 574 struct aldap *al; 575 576 where = "connect"; 577 if ((al = client_aldap_open(&idm->idm_addr)) == NULL) 578 return (-1); 579 580 if (idm->idm_flags & F_NEEDAUTH) { 581 where = "binding"; 582 if (aldap_bind(al, idm->idm_binddn, idm->idm_bindcred) == -1) 583 goto bad; 584 585 where = "parsing"; 586 if ((m = aldap_parse(al)) == NULL) 587 goto bad; 588 where = "verifying msgid"; 589 if (al->msgid != m->msgid) { 590 aldap_freemsg(m); 591 goto bad; 592 } 593 aldap_freemsg(m); 594 } 595 596 memset(attrs, 0, sizeof(attrs)); 597 for (i = 0, j = 0; i < ATTR_MAX; i++) { 598 if (idm->idm_flags & F_FIXED_ATTR(i)) 599 continue; 600 attrs[j++] = idm->idm_attrs[i]; 601 } 602 attrs[j] = NULL; 603 604 /* 605 * build password line. 606 */ 607 where = "search"; 608 log_debug("searching password entries"); 609 if (client_search_idm(env, idm, al, attrs, 610 idm->idm_filters[FILTER_USER], 0, ATTR_MAX, IMSG_PW_ENTRY) == -1) 611 goto bad; 612 613 memset(attrs, 0, sizeof(attrs)); 614 for (i = ATTR_GR_MIN, j = 0; i < ATTR_GR_MAX; i++) { 615 if (idm->idm_flags & F_FIXED_ATTR(i)) 616 continue; 617 attrs[j++] = idm->idm_attrs[i]; 618 } 619 attrs[j] = NULL; 620 621 /* 622 * build group line. 623 */ 624 where = "search"; 625 log_debug("searching group entries"); 626 if (client_search_idm(env, idm, al, attrs, 627 idm->idm_filters[FILTER_GROUP], ATTR_GR_MIN, ATTR_GR_MAX, 628 IMSG_GRP_ENTRY) == -1) 629 goto bad; 630 631 aldap_close(al); 632 633 idm->idm_state = STATE_LDAP_DONE; 634 635 return (0); 636 bad: 637 aldap_close(al); 638 log_debug("directory %s errored out in %s", idm->idm_name, where); 639 return (-1); 640 } 641 642 void client_periodic_update(int fd,short event,void * p)643 client_periodic_update(int fd, short event, void *p) 644 { 645 struct env *env = p; 646 647 struct idm *idm; 648 int fail_cnt = 0; 649 650 /* If LDAP isn't finished, notify the master process to trash the 651 * update. */ 652 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 653 if (idm->idm_state < STATE_LDAP_DONE) 654 fail_cnt++; 655 656 idm->idm_state = STATE_NONE; 657 658 client_addr_free(idm); 659 } 660 if (fail_cnt > 0) { 661 log_debug("trash the update"); 662 imsg_compose_event(env->sc_iev, IMSG_TRASH_UPDATE, 0, 0, -1, 663 NULL, 0); 664 } 665 666 client_configure(env); 667 } 668 669 void client_configure(struct env * env)670 client_configure(struct env *env) 671 { 672 struct timeval tv; 673 struct idm *idm; 674 u_int16_t dlen; 675 676 log_debug("connecting to directories"); 677 678 imsg_compose_event(env->sc_iev, IMSG_START_UPDATE, 0, 0, -1, NULL, 0); 679 680 /* Start the DNS lookups */ 681 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 682 dlen = strlen(idm->idm_name) + 1; 683 imsg_compose_event(env->sc_iev_dns, IMSG_HOST_DNS, idm->idm_id, 684 0, -1, idm->idm_name, dlen); 685 } 686 687 tv.tv_sec = env->sc_conf_tv.tv_sec; 688 tv.tv_usec = env->sc_conf_tv.tv_usec; 689 evtimer_set(&env->sc_conf_ev, client_periodic_update, env); 690 evtimer_add(&env->sc_conf_ev, &tv); 691 } 692