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