1 /* $OpenBSD: ldapclient.c,v 1.31 2014/11/16 23:24:44 tedu Exp $ */
2 /* $FreeBSD: stable/12/usr.sbin/ypldap/ldapclient.c 309393 2016-12-02 06:07:27Z araujo $ */
3
4 /*
5 * Copyright (c) 2008 Alexander Schrijver <aschrijver@openbsd.org>
6 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose with or without fee is hereby granted, provided that the above
10 * copyright notice and this permission notice appear in all copies.
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 */
20
21 #include <sys/types.h>
22 #include <sys/param.h>
23 #include <sys/queue.h>
24 #include <sys/socket.h>
25 #include <sys/tree.h>
26
27 #include <netinet/in.h>
28 #include <arpa/inet.h>
29
30 #include <netdb.h>
31 #include <errno.h>
32 #include <err.h>
33 #include <event.h>
34 #include <fcntl.h>
35 #include <unistd.h>
36 #include <pwd.h>
37 #include <signal.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41
42 #include "aldap.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 *
client_aldap_open(struct ypldap_addr_list * addr)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->sa_len, 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->sa_len) == 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
client_addr_init(struct idm * idm)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
client_addr_free(struct idm * idm)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
client_sig_handler(int sig,short event,void * p)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
client_dispatch_dns(int fd,short events,void * p)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
client_dispatch_parent(int fd,short events,void * p)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
client_shutdown(void)340 client_shutdown(void)
341 {
342 log_info("ldap client exiting");
343 _exit(0);
344 }
345
346 pid_t
ldapclient(int pipe_main2client[2])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
388 #ifndef DEBUG
389 if (setgroups(1, &pw->pw_gid) ||
390 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
391 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
392 fatal("cannot drop privileges");
393 #else
394 #warning disabling privilege revocation in DEBUG mode
395 #endif
396
397 event_init();
398 signal(SIGPIPE, SIG_IGN);
399 signal_set(&ev_sigint, SIGINT, client_sig_handler, NULL);
400 signal_set(&ev_sigterm, SIGTERM, client_sig_handler, NULL);
401 signal_add(&ev_sigint, NULL);
402 signal_add(&ev_sigterm, NULL);
403
404 close(pipe_main2client[0]);
405 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
406 fatal(NULL);
407 if ((env.sc_iev_dns = calloc(1, sizeof(*env.sc_iev_dns))) == NULL)
408 fatal(NULL);
409
410 env.sc_iev->events = EV_READ;
411 env.sc_iev->data = &env;
412 imsg_init(&env.sc_iev->ibuf, pipe_main2client[1]);
413 env.sc_iev->handler = client_dispatch_parent;
414 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
415 env.sc_iev->handler, &env);
416 event_add(&env.sc_iev->ev, NULL);
417
418 env.sc_iev_dns->events = EV_READ;
419 env.sc_iev_dns->data = &env;
420 imsg_init(&env.sc_iev_dns->ibuf, pipe_dns[0]);
421 env.sc_iev_dns->handler = client_dispatch_dns;
422 event_set(&env.sc_iev_dns->ev, env.sc_iev_dns->ibuf.fd,
423 env.sc_iev_dns->events, env.sc_iev_dns->handler, &env);
424 event_add(&env.sc_iev_dns->ev, NULL);
425
426 event_dispatch();
427 client_shutdown();
428
429 return (0);
430
431 }
432
433 int
client_build_req(struct idm * idm,struct idm_req * ir,struct aldap_message * m,int min_attr,int max_attr)434 client_build_req(struct idm *idm, struct idm_req *ir, struct aldap_message *m,
435 int min_attr, int max_attr)
436 {
437 char **ldap_attrs;
438 int i, k;
439
440 memset(ir, 0, sizeof(*ir));
441 for (i = min_attr; i < max_attr; i++) {
442 if (idm->idm_flags & F_FIXED_ATTR(i)) {
443 if (strlcat(ir->ir_line, idm->idm_attrs[i],
444 sizeof(ir->ir_line)) >= sizeof(ir->ir_line))
445 /*
446 * entry yields a line > 1024, trash it.
447 */
448 return (-1);
449
450 if (i == ATTR_UID) {
451 ir->ir_key.ik_uid = strtonum(
452 idm->idm_attrs[i], 0,
453 UID_MAX, NULL);
454 } else if (i == ATTR_GR_GID) {
455 ir->ir_key.ik_gid = strtonum(
456 idm->idm_attrs[i], 0,
457 GID_MAX, NULL);
458 }
459 } else if (idm->idm_list & F_LIST(i)) {
460 aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs);
461 for (k = 0; k >= 0 && ldap_attrs && ldap_attrs[k] != NULL; k++) {
462 /* XXX: Fail when attributes have illegal characters e.g. ',' */
463 if (strlcat(ir->ir_line, ldap_attrs[k],
464 sizeof(ir->ir_line)) >= sizeof(ir->ir_line))
465 continue;
466 if (ldap_attrs[k+1] != NULL)
467 if (strlcat(ir->ir_line, ",",
468 sizeof(ir->ir_line))
469 >= sizeof(ir->ir_line)) {
470 aldap_free_attr(ldap_attrs);
471 return (-1);
472 }
473 }
474 aldap_free_attr(ldap_attrs);
475 } else {
476 if (aldap_match_attr(m, idm->idm_attrs[i], &ldap_attrs) == -1)
477 return (-1);
478 if (strlcat(ir->ir_line, ldap_attrs[0],
479 sizeof(ir->ir_line)) >= sizeof(ir->ir_line)) {
480 aldap_free_attr(ldap_attrs);
481 return (-1);
482 }
483 if (i == ATTR_UID) {
484 ir->ir_key.ik_uid = strtonum(
485 ldap_attrs[0], 0, UID_MAX, NULL);
486 } else if (i == ATTR_GR_GID) {
487 ir->ir_key.ik_uid = strtonum(
488 ldap_attrs[0], 0, GID_MAX, NULL);
489 }
490 aldap_free_attr(ldap_attrs);
491 }
492
493 if (i + 1 != max_attr)
494 if (strlcat(ir->ir_line, ":",
495 sizeof(ir->ir_line)) >= sizeof(ir->ir_line))
496 return (-1);
497 }
498
499 return (0);
500 }
501
502 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)503 client_search_idm(struct env *env, struct idm *idm, struct aldap *al,
504 char **attrs, char *filter, int min_attr, int max_attr,
505 enum imsg_type type)
506 {
507 struct idm_req ir;
508 struct aldap_message *m;
509 struct aldap_page_control *pg = NULL;
510 const char *errstr;
511 char *dn;
512
513 dn = idm->idm_basedn;
514 if (type == IMSG_GRP_ENTRY && idm->idm_groupdn[0] != '\0')
515 dn = idm->idm_groupdn;
516
517 do {
518 if (aldap_search(al, dn, LDAP_SCOPE_SUBTREE,
519 filter, attrs, 0, 0, 0, pg) == -1) {
520 aldap_get_errno(al, &errstr);
521 log_debug("%s", errstr);
522 return (-1);
523 }
524
525 if (pg != NULL) {
526 aldap_freepage(pg);
527 pg = NULL;
528 }
529
530 while ((m = aldap_parse(al)) != NULL) {
531 if (al->msgid != m->msgid) {
532 goto fail;
533 }
534
535 if (m->message_type == LDAP_RES_SEARCH_RESULT) {
536 if (m->page != NULL && m->page->cookie_len != 0)
537 pg = m->page;
538 else
539 pg = NULL;
540
541 aldap_freemsg(m);
542 break;
543 }
544
545 if (m->message_type != LDAP_RES_SEARCH_ENTRY) {
546 goto fail;
547 }
548
549 if (client_build_req(idm, &ir, m, min_attr, max_attr) == 0)
550 imsg_compose_event(env->sc_iev, type, 0, 0, -1,
551 &ir, sizeof(ir));
552
553 aldap_freemsg(m);
554 }
555 } while (pg != NULL);
556
557 return (0);
558
559 fail:
560 aldap_freemsg(m);
561 if (pg != NULL) {
562 aldap_freepage(pg);
563 }
564
565 return (-1);
566 }
567
568 int
client_try_idm(struct env * env,struct idm * idm)569 client_try_idm(struct env *env, struct idm *idm)
570 {
571 const char *where;
572 char *attrs[ATTR_MAX+1];
573 int i, j;
574 struct aldap_message *m;
575 struct aldap *al;
576
577 where = "connect";
578 if ((al = client_aldap_open(&idm->idm_addr)) == NULL)
579 return (-1);
580
581 if (idm->idm_flags & F_NEEDAUTH) {
582 where = "binding";
583 if (aldap_bind(al, idm->idm_binddn, idm->idm_bindcred) == -1)
584 goto bad;
585
586 where = "parsing";
587 if ((m = aldap_parse(al)) == NULL)
588 goto bad;
589 where = "verifying msgid";
590 if (al->msgid != m->msgid) {
591 aldap_freemsg(m);
592 goto bad;
593 }
594 aldap_freemsg(m);
595 }
596
597 memset(attrs, 0, sizeof(attrs));
598 for (i = 0, j = 0; i < ATTR_MAX; i++) {
599 if (idm->idm_flags & F_FIXED_ATTR(i))
600 continue;
601 attrs[j++] = idm->idm_attrs[i];
602 }
603 attrs[j] = NULL;
604
605 /*
606 * build password line.
607 */
608 where = "search";
609 log_debug("searching password entries");
610 if (client_search_idm(env, idm, al, attrs,
611 idm->idm_filters[FILTER_USER], 0, ATTR_MAX, IMSG_PW_ENTRY) == -1)
612 goto bad;
613
614 memset(attrs, 0, sizeof(attrs));
615 for (i = ATTR_GR_MIN, j = 0; i < ATTR_GR_MAX; i++) {
616 if (idm->idm_flags & F_FIXED_ATTR(i))
617 continue;
618 attrs[j++] = idm->idm_attrs[i];
619 }
620 attrs[j] = NULL;
621
622 /*
623 * build group line.
624 */
625 where = "search";
626 log_debug("searching group entries");
627 if (client_search_idm(env, idm, al, attrs,
628 idm->idm_filters[FILTER_GROUP], ATTR_GR_MIN, ATTR_GR_MAX,
629 IMSG_GRP_ENTRY) == -1)
630 goto bad;
631
632 aldap_close(al);
633
634 idm->idm_state = STATE_LDAP_DONE;
635
636 return (0);
637 bad:
638 aldap_close(al);
639 log_debug("directory %s errored out in %s", idm->idm_name, where);
640 return (-1);
641 }
642
643 void
client_periodic_update(int fd,short event,void * p)644 client_periodic_update(int fd, short event, void *p)
645 {
646 struct env *env = p;
647
648 struct idm *idm;
649 int fail_cnt = 0;
650
651 /* If LDAP isn't finished, notify the master process to trash the
652 * update. */
653 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
654 if (idm->idm_state < STATE_LDAP_DONE)
655 fail_cnt++;
656
657 idm->idm_state = STATE_NONE;
658
659 client_addr_free(idm);
660 }
661 if (fail_cnt > 0) {
662 log_debug("trash the update");
663 imsg_compose_event(env->sc_iev, IMSG_TRASH_UPDATE, 0, 0, -1,
664 NULL, 0);
665 }
666
667 client_configure(env);
668 }
669
670 void
client_configure(struct env * env)671 client_configure(struct env *env)
672 {
673 struct timeval tv;
674 struct idm *idm;
675 u_int16_t dlen;
676
677 log_debug("connecting to directories");
678
679 imsg_compose_event(env->sc_iev, IMSG_START_UPDATE, 0, 0, -1, NULL, 0);
680
681 /* Start the DNS lookups */
682 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
683 dlen = strlen(idm->idm_name) + 1;
684 imsg_compose_event(env->sc_iev_dns, IMSG_HOST_DNS, idm->idm_id,
685 0, -1, idm->idm_name, dlen);
686 }
687
688 tv.tv_sec = env->sc_conf_tv.tv_sec;
689 tv.tv_usec = env->sc_conf_tv.tv_usec;
690 evtimer_set(&env->sc_conf_ev, client_periodic_update, env);
691 evtimer_add(&env->sc_conf_ev, &tv);
692 }
693