1 /* $OpenBSD: ldapclient.c,v 1.23 2011/08/28 16:37:28 aschrijver 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 <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 40 #include "aldap.h" 41 #include "ypldap.h" 42 43 void client_sig_handler(int, short, void *); 44 void client_dispatch_dns(int, short, void *); 45 void client_dispatch_parent(int, short, void *); 46 void client_shutdown(void); 47 void client_connect(int, short, void *); 48 void client_configure(struct env *); 49 void client_periodic_update(int, short, void *); 50 int client_build_req(struct idm *, struct idm_req *, struct aldap_message *, 51 int, int); 52 int client_search_idm(struct env *, struct idm *, struct aldap *, 53 char **, char *, int, int, enum imsg_type); 54 int client_try_idm(struct env *, struct idm *); 55 int client_addr_init(struct idm *); 56 int client_addr_free(struct idm *); 57 58 struct aldap *client_aldap_open(struct ypldap_addr *); 59 60 /* 61 * dummy wrapper to provide aldap_init with its fd's. 62 */ 63 struct aldap * 64 client_aldap_open(struct ypldap_addr *addr) 65 { 66 int fd = -1; 67 struct ypldap_addr *p; 68 69 for (p = addr; p != NULL; p = p->next) { 70 char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; 71 struct sockaddr *sa = (struct sockaddr *)&p->ss; 72 73 if (getnameinfo(sa, SA_LEN(sa), hbuf, sizeof(hbuf), sbuf, 74 sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV)) 75 errx(1, "could not get numeric hostname"); 76 77 if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) 78 return NULL; 79 80 if (connect(fd, sa, SA_LEN(sa)) == 0) 81 break; 82 83 warn("connect to %s port %s (%s) failed", hbuf, sbuf, "tcp"); 84 close(fd); 85 } 86 87 if (fd == -1) 88 return NULL; 89 90 return aldap_init(fd); 91 } 92 93 int 94 client_addr_init(struct idm *idm) 95 { 96 struct sockaddr_in *sa_in; 97 struct sockaddr_in6 *sa_in6; 98 struct ypldap_addr *h; 99 100 for (h = idm->idm_addr; h != NULL; h = h->next) { 101 switch (h->ss.ss_family) { 102 case AF_INET: 103 sa_in = (struct sockaddr_in *)&h->ss; 104 if (ntohs(sa_in->sin_port) == 0) 105 sa_in->sin_port = htons(LDAP_PORT); 106 idm->idm_state = STATE_DNS_DONE; 107 break; 108 case AF_INET6: 109 sa_in6 = (struct sockaddr_in6 *)&h->ss; 110 if (ntohs(sa_in6->sin6_port) == 0) 111 sa_in6->sin6_port = htons(LDAP_PORT); 112 idm->idm_state = STATE_DNS_DONE; 113 break; 114 default: 115 fatalx("king bula sez: wrong AF in client_addr_init"); 116 /* not reached */ 117 } 118 } 119 120 return (0); 121 } 122 123 int 124 client_addr_free(struct idm *idm) 125 { 126 struct ypldap_addr *h, *p; 127 128 if (idm->idm_addr == NULL) 129 return (-1); 130 131 for (h = idm->idm_addr; h != NULL; h = p) { 132 p = h->next; 133 free(h); 134 } 135 136 idm->idm_addr = NULL; 137 138 return (0); 139 } 140 141 void 142 client_sig_handler(int sig, short event, void *p) 143 { 144 switch (sig) { 145 case SIGINT: 146 case SIGTERM: 147 client_shutdown(); 148 break; 149 default: 150 fatalx("unexpected signal"); 151 } 152 } 153 154 void 155 client_dispatch_dns(int fd, short event, void *p) 156 { 157 struct imsg imsg; 158 u_int16_t dlen; 159 u_char *data; 160 struct ypldap_addr *h; 161 int n, wait_cnt = 0; 162 struct idm *idm; 163 int shut = 0; 164 165 struct env *env = p; 166 struct imsgev *iev = env->sc_iev_dns; 167 struct imsgbuf *ibuf = &iev->ibuf; 168 169 switch (event) { 170 case EV_READ: 171 if ((n = imsg_read(ibuf)) == -1) 172 fatal("imsg_read error"); 173 if (n == 0) 174 shut = 1; 175 break; 176 case EV_WRITE: 177 if (msgbuf_write(&ibuf->w) == -1) 178 fatal("msgbuf_write"); 179 imsg_event_add(iev); 180 return; 181 default: 182 fatalx("unknown event"); 183 } 184 185 for (;;) { 186 if ((n = imsg_get(ibuf, &imsg)) == -1) 187 fatal("client_dispatch_dns: imsg_get error"); 188 if (n == 0) 189 break; 190 191 switch (imsg.hdr.type) { 192 case IMSG_HOST_DNS: 193 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) 194 if (idm->idm_id == imsg.hdr.peerid) 195 break; 196 if (idm == NULL) { 197 log_warnx("IMSG_HOST_DNS with invalid peerID"); 198 break; 199 } 200 if (idm->idm_addr != NULL) { 201 log_warnx("IMSG_HOST_DNS but addr != NULL!"); 202 break; 203 } 204 205 dlen = imsg.hdr.len - IMSG_HEADER_SIZE; 206 if (dlen == 0) { /* no data -> temp error */ 207 idm->idm_state = STATE_DNS_TEMPFAIL; 208 break; 209 } 210 211 data = (u_char *)imsg.data; 212 while (dlen >= sizeof(struct sockaddr_storage)) { 213 if ((h = calloc(1, sizeof(struct ypldap_addr))) == 214 NULL) 215 fatal(NULL); 216 memcpy(&h->ss, data, sizeof(h->ss)); 217 218 if (idm->idm_addr == NULL) 219 h->next = NULL; 220 else 221 h->next = idm->idm_addr; 222 223 idm->idm_addr = h; 224 225 data += sizeof(h->ss); 226 dlen -= sizeof(h->ss); 227 } 228 if (dlen != 0) 229 fatalx("IMSG_HOST_DNS: dlen != 0"); 230 231 client_addr_init(idm); 232 233 break; 234 default: 235 break; 236 } 237 imsg_free(&imsg); 238 } 239 240 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 241 if (client_try_idm(env, idm) == -1) 242 idm->idm_state = STATE_LDAP_FAIL; 243 244 if (idm->idm_state < STATE_LDAP_DONE) 245 wait_cnt++; 246 } 247 if (wait_cnt == 0) 248 imsg_compose_event(env->sc_iev, IMSG_END_UPDATE, 0, 0, -1, 249 NULL, 0); 250 251 if (!shut) 252 imsg_event_add(iev); 253 else { 254 /* this pipe is dead, so remove the event handler */ 255 event_del(&iev->ev); 256 event_loopexit(NULL); 257 } 258 } 259 260 void 261 client_dispatch_parent(int fd, short event, void *p) 262 { 263 int n; 264 int shut = 0; 265 struct imsg imsg; 266 struct env *env = p; 267 struct imsgev *iev = env->sc_iev; 268 struct imsgbuf *ibuf = &iev->ibuf; 269 270 271 switch (event) { 272 case EV_READ: 273 if ((n = imsg_read(ibuf)) == -1) 274 fatal("imsg_read error"); 275 if (n == 0) 276 shut = 1; 277 break; 278 case EV_WRITE: 279 if (msgbuf_write(&ibuf->w) == -1) 280 fatal("msgbuf_write"); 281 imsg_event_add(iev); 282 return; 283 default: 284 fatalx("unknown event"); 285 } 286 287 for (;;) { 288 if ((n = imsg_get(ibuf, &imsg)) == -1) 289 fatal("client_dispatch_parent: imsg_get error"); 290 if (n == 0) 291 break; 292 293 switch (imsg.hdr.type) { 294 case IMSG_CONF_START: { 295 struct env params; 296 297 if (env->sc_flags & F_CONFIGURING) { 298 log_warnx("configuration already in progress"); 299 break; 300 } 301 memcpy(¶ms, imsg.data, sizeof(params)); 302 log_debug("configuration starting"); 303 env->sc_flags |= F_CONFIGURING; 304 purge_config(env); 305 memcpy(&env->sc_conf_tv, ¶ms.sc_conf_tv, 306 sizeof(env->sc_conf_tv)); 307 env->sc_flags |= params.sc_flags; 308 break; 309 } 310 case IMSG_CONF_IDM: { 311 struct idm *idm; 312 313 if (!(env->sc_flags & F_CONFIGURING)) 314 break; 315 if ((idm = calloc(1, sizeof(*idm))) == NULL) 316 fatal(NULL); 317 memcpy(idm, imsg.data, sizeof(*idm)); 318 idm->idm_env = env; 319 TAILQ_INSERT_TAIL(&env->sc_idms, idm, idm_entry); 320 break; 321 } 322 case IMSG_CONF_END: 323 env->sc_flags &= ~F_CONFIGURING; 324 log_debug("applying configuration"); 325 client_configure(env); 326 break; 327 default: 328 log_debug("client_dispatch_parent: unexpect imsg %d", 329 imsg.hdr.type); 330 331 break; 332 } 333 imsg_free(&imsg); 334 } 335 if (!shut) 336 imsg_event_add(iev); 337 else { 338 /* this pipe is dead, so remove the event handler */ 339 event_del(&iev->ev); 340 event_loopexit(NULL); 341 } 342 } 343 344 void 345 client_shutdown(void) 346 { 347 log_info("ldap client exiting"); 348 _exit(0); 349 } 350 351 pid_t 352 ldapclient(int pipe_main2client[2]) 353 { 354 pid_t pid, dns_pid; 355 int pipe_dns[2]; 356 struct passwd *pw; 357 struct event ev_sigint; 358 struct event ev_sigterm; 359 struct env env; 360 361 switch (pid = fork()) { 362 case -1: 363 fatal("cannot fork"); 364 break; 365 case 0: 366 break; 367 default: 368 return (pid); 369 } 370 371 bzero(&env, sizeof(env)); 372 TAILQ_INIT(&env.sc_idms); 373 374 if ((pw = getpwnam(YPLDAP_USER)) == NULL) 375 fatal("getpwnam"); 376 377 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_dns) == -1) 378 fatal("socketpair"); 379 dns_pid = ypldap_dns(pipe_dns, pw); 380 close(pipe_dns[1]); 381 382 #ifndef DEBUG 383 if (chroot(pw->pw_dir) == -1) 384 fatal("chroot"); 385 if (chdir("/") == -1) 386 fatal("chdir"); 387 #else 388 #warning disabling chrooting in DEBUG mode 389 #endif 390 setproctitle("ldap client"); 391 ypldap_process = PROC_CLIENT; 392 393 #ifndef DEBUG 394 if (setgroups(1, &pw->pw_gid) || 395 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) || 396 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) 397 fatal("cannot drop privileges"); 398 #else 399 #warning disabling privilege revocation in DEBUG mode 400 #endif 401 402 event_init(); 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 bzero(ir, 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 if (aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs) == -1) 465 return (-1); 466 if (ldap_attrs[0] == NULL) 467 return (-1); 468 for (k = 0; k >= 0 && ldap_attrs[k] != NULL; k++) { 469 /* XXX: Fail when attributes have ilegal characters e.g. ',' */ 470 if (strlcat(ir->ir_line, ldap_attrs[k], 471 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 472 continue; 473 if (ldap_attrs[k+1] != NULL) 474 if (strlcat(ir->ir_line, ",", 475 sizeof(ir->ir_line)) 476 >= sizeof(ir->ir_line)) { 477 aldap_free_attr(ldap_attrs); 478 return (-1); 479 } 480 } 481 aldap_free_attr(ldap_attrs); 482 } else { 483 if (aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs) == -1) 484 return (-1); 485 if (ldap_attrs[0] == NULL) 486 return (-1); 487 if (strlcat(ir->ir_line, ldap_attrs[0], 488 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) { 489 aldap_free_attr(ldap_attrs); 490 return (-1); 491 } 492 if (i == ATTR_UID) { 493 ir->ir_key.ik_uid = strtonum( 494 ldap_attrs[0], 0, UID_MAX, NULL); 495 } else if (i == ATTR_GR_GID) { 496 ir->ir_key.ik_uid = strtonum( 497 ldap_attrs[0], 0, GID_MAX, NULL); 498 } 499 aldap_free_attr(ldap_attrs); 500 } 501 502 if (i + 1 != max_attr) 503 if (strlcat(ir->ir_line, ":", 504 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) 505 return (-1); 506 } 507 508 return (0); 509 } 510 511 int 512 client_search_idm(struct env *env, struct idm *idm, struct aldap *al, 513 char **attrs, char *filter, int min_attr, int max_attr, 514 enum imsg_type type) 515 { 516 struct idm_req ir; 517 struct aldap_message *m; 518 const char *errstr; 519 520 if (aldap_search(al, idm->idm_basedn, LDAP_SCOPE_SUBTREE, 521 filter, attrs, 0, 0, 0) == -1) { 522 aldap_get_errno(al, &errstr); 523 log_debug("%s", errstr); 524 return (-1); 525 } 526 527 while ((m = aldap_parse(al)) != NULL) { 528 if (al->msgid != m->msgid) { 529 aldap_freemsg(m); 530 return (-1); 531 } 532 /* end of the search result chain */ 533 if (m->message_type == LDAP_RES_SEARCH_RESULT) { 534 aldap_freemsg(m); 535 break; 536 } 537 /* search entry; the rest we won't handle */ 538 if (m->message_type != LDAP_RES_SEARCH_ENTRY) { 539 aldap_freemsg(m); 540 return (-1); 541 } 542 543 if (client_build_req(idm, &ir, m, min_attr, max_attr) == 0) 544 imsg_compose_event(env->sc_iev, type, 0, 0, -1, 545 &ir, sizeof(ir)); 546 aldap_freemsg(m); 547 } 548 549 return (0); 550 } 551 552 int 553 client_try_idm(struct env *env, struct idm *idm) 554 { 555 const char *where; 556 char *attrs[ATTR_MAX+1]; 557 int i, j; 558 struct aldap_message *m; 559 struct aldap *al; 560 561 where = "connect"; 562 if ((al = client_aldap_open(idm->idm_addr)) == NULL) 563 return (-1); 564 565 if (idm->idm_flags & F_NEEDAUTH) { 566 where = "binding"; 567 if (aldap_bind(al, idm->idm_binddn, idm->idm_bindcred) == -1) 568 goto bad; 569 570 where = "parsing"; 571 if ((m = aldap_parse(al)) == NULL) 572 goto bad; 573 where = "verifying msgid"; 574 if (al->msgid != m->msgid) { 575 aldap_freemsg(m); 576 goto bad; 577 } 578 aldap_freemsg(m); 579 } 580 581 bzero(attrs, sizeof(attrs)); 582 for (i = 0, j = 0; i < ATTR_MAX; i++) { 583 if (idm->idm_flags & F_FIXED_ATTR(i)) 584 continue; 585 attrs[j++] = idm->idm_attrs[i]; 586 } 587 attrs[j] = NULL; 588 589 /* 590 * build password line. 591 */ 592 where = "search"; 593 log_debug("searching password entries"); 594 if (client_search_idm(env, idm, al, attrs, 595 idm->idm_filters[FILTER_USER], 0, ATTR_MAX, IMSG_PW_ENTRY) == -1) 596 goto bad; 597 598 bzero(attrs, sizeof(attrs)); 599 for (i = ATTR_GR_MIN, j = 0; i < ATTR_GR_MAX; i++) { 600 if (idm->idm_flags & F_FIXED_ATTR(i)) 601 continue; 602 attrs[j++] = idm->idm_attrs[i]; 603 } 604 attrs[j] = NULL; 605 606 /* 607 * build group line. 608 */ 609 where = "search"; 610 log_debug("searching group entries"); 611 if (client_search_idm(env, idm, al, attrs, 612 idm->idm_filters[FILTER_GROUP], ATTR_GR_MIN, ATTR_GR_MAX, 613 IMSG_GRP_ENTRY) == -1) 614 goto bad; 615 616 aldap_close(al); 617 618 idm->idm_state = STATE_LDAP_DONE; 619 620 return (0); 621 bad: 622 aldap_close(al); 623 log_debug("directory %s errored out in %s", idm->idm_name, where); 624 return (-1); 625 } 626 627 void 628 client_periodic_update(int fd, short event, void *p) 629 { 630 struct env *env = p; 631 632 struct idm *idm; 633 int fail_cnt = 0; 634 635 /* If LDAP isn't finished, notify the master process to trash the 636 * update. */ 637 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 638 if (idm->idm_state < STATE_LDAP_DONE) 639 fail_cnt++; 640 641 idm->idm_state = STATE_NONE; 642 643 client_addr_free(idm); 644 } 645 if (fail_cnt > 0) { 646 log_debug("trash the update"); 647 imsg_compose_event(env->sc_iev, IMSG_TRASH_UPDATE, 0, 0, -1, 648 NULL, 0); 649 } 650 651 client_configure(env); 652 } 653 654 void 655 client_configure(struct env *env) 656 { 657 struct timeval tv; 658 struct idm *idm; 659 u_int16_t dlen; 660 661 log_debug("connecting to directories"); 662 663 imsg_compose_event(env->sc_iev, IMSG_START_UPDATE, 0, 0, -1, NULL, 0); 664 665 /* Start the DNS lookups */ 666 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) { 667 dlen = strlen(idm->idm_name) + 1; 668 imsg_compose_event(env->sc_iev_dns, IMSG_HOST_DNS, idm->idm_id, 669 0, -1, idm->idm_name, dlen); 670 } 671 672 tv.tv_sec = env->sc_conf_tv.tv_sec; 673 tv.tv_usec = env->sc_conf_tv.tv_usec; 674 evtimer_set(&env->sc_conf_ev, client_periodic_update, env); 675 evtimer_add(&env->sc_conf_ev, &tv); 676 } 677