1 /* $OpenBSD: ypldap.c,v 1.16 2015/11/02 10:06:06 jmatthew Exp $ */
2 /* $FreeBSD */
3
4 /*
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/signal.h>
25 #include <sys/tree.h>
26 #include <sys/wait.h>
27
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30
31 #include <err.h>
32 #include <errno.h>
33 #include <event.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 "ypldap.h"
42
43 enum ypldap_process_type ypldap_process;
44
45 __dead2 void usage(void);
46 int check_child(pid_t, const char *);
47 void main_sig_handler(int, short, void *);
48 void main_shutdown(void);
49 void main_dispatch_client(int, short, void *);
50 void main_configure_client(struct env *);
51 void main_init_timer(int, short, void *);
52 void main_start_update(struct env *);
53 void main_trash_update(struct env *);
54 void main_end_update(struct env *);
55 int main_create_user_groups(struct env *);
56 void purge_config(struct env *);
57 void reconfigure(struct env *);
58
59 int pipe_main2client[2];
60
61 pid_t client_pid = 0;
62 char *conffile = YPLDAP_CONF_FILE;
63 int opts = 0;
64
65 void
usage(void)66 usage(void)
67 {
68 extern const char *__progname;
69
70 fprintf(stderr, "usage: %s [-dnv] [-D macro=value] [-f file]\n",
71 __progname);
72 exit(1);
73 }
74
75 int
check_child(pid_t pid,const char * pname)76 check_child(pid_t pid, const char *pname)
77 {
78 int status;
79
80 if (waitpid(pid, &status, WNOHANG) > 0) {
81 if (WIFEXITED(status)) {
82 log_warnx("check_child: lost child %s exited", pname);
83 return (1);
84 }
85 if (WIFSIGNALED(status)) {
86 log_warnx("check_child: lost child %s terminated; "
87 "signal %d", pname, WTERMSIG(status));
88 return (1);
89 }
90 }
91 return (0);
92 }
93
94 /* ARGUSED */
95 void
main_sig_handler(int sig,short event,void * p)96 main_sig_handler(int sig, short event, void *p)
97 {
98 int die = 0;
99
100 switch (sig) {
101 case SIGTERM:
102 case SIGINT:
103 die = 1;
104 /* FALLTHROUGH */
105 case SIGCHLD:
106 if (check_child(client_pid, "ldap client")) {
107 client_pid = 0;
108 die = 1;
109 }
110 if (die)
111 main_shutdown();
112 break;
113 case SIGHUP:
114 /* reconfigure */
115 break;
116 default:
117 fatalx("unexpected signal");
118 }
119 }
120
121 void
main_shutdown(void)122 main_shutdown(void)
123 {
124 _exit(0);
125 }
126
127 void
main_start_update(struct env * env)128 main_start_update(struct env *env)
129 {
130 env->update_trashed = 0;
131
132 log_debug("starting directory update");
133 env->sc_user_line_len = 0;
134 env->sc_group_line_len = 0;
135 if ((env->sc_user_names_t = calloc(1,
136 sizeof(*env->sc_user_names_t))) == NULL ||
137 (env->sc_group_names_t = calloc(1,
138 sizeof(*env->sc_group_names_t))) == NULL)
139 fatal(NULL);
140 RB_INIT(env->sc_user_names_t);
141 RB_INIT(env->sc_group_names_t);
142 }
143
144 /*
145 * XXX: Currently this function should only be called when updating is
146 * finished. A notification should be send to ldapclient that it should stop
147 * sending new pwd/grp entries before it can be called from different places.
148 */
149 void
main_trash_update(struct env * env)150 main_trash_update(struct env *env)
151 {
152 struct userent *ue;
153 struct groupent *ge;
154
155 env->update_trashed = 1;
156
157 while ((ue = RB_ROOT(env->sc_user_names_t)) != NULL) {
158 RB_REMOVE(user_name_tree,
159 env->sc_user_names_t, ue);
160 free(ue->ue_line);
161 free(ue->ue_netid_line);
162 free(ue);
163 }
164 free(env->sc_user_names_t);
165 env->sc_user_names_t = NULL;
166 while ((ge = RB_ROOT(env->sc_group_names_t))
167 != NULL) {
168 RB_REMOVE(group_name_tree,
169 env->sc_group_names_t, ge);
170 free(ge->ge_line);
171 free(ge);
172 }
173 free(env->sc_group_names_t);
174 env->sc_group_names_t = NULL;
175 }
176
177 int
main_create_user_groups(struct env * env)178 main_create_user_groups(struct env *env)
179 {
180 struct userent *ue;
181 struct userent ukey;
182 struct groupent *ge;
183 gid_t pw_gid;
184 char *bp, *cp;
185 char *p;
186 const char *errstr = NULL;
187 size_t len;
188
189 RB_FOREACH(ue, user_name_tree, env->sc_user_names_t) {
190 bp = cp = ue->ue_line;
191
192 /* name */
193 bp += strlen(bp) + 1;
194
195 /* password */
196 bp += strcspn(bp, ":") + 1;
197
198 /* uid */
199 bp += strcspn(bp, ":") + 1;
200
201 /* gid */
202 bp[strcspn(bp, ":")] = '\0';
203
204 pw_gid = (gid_t)strtonum(bp, 0, GID_MAX, &errstr);
205 if (errstr) {
206 log_warnx("main: failed to parse gid for uid: %d\n", ue->ue_uid);
207 return (-1);
208 }
209
210 /* bring gid column back to its proper state */
211 bp[strlen(bp)] = ':';
212
213 if ((ue->ue_netid_line = calloc(1, LINE_WIDTH)) == NULL) {
214 return (-1);
215 }
216
217 if (snprintf(ue->ue_netid_line, LINE_WIDTH-1, "%d:%d", ue->ue_uid, pw_gid) >= LINE_WIDTH) {
218
219 return (-1);
220 }
221
222 ue->ue_gid = pw_gid;
223 }
224
225 RB_FOREACH(ge, group_name_tree, env->sc_group_names_t) {
226 bp = cp = ge->ge_line;
227
228 /* name */
229 bp += strlen(bp) + 1;
230
231 /* password */
232 bp += strcspn(bp, ":") + 1;
233
234 /* gid */
235 bp += strcspn(bp, ":") + 1;
236
237 cp = bp;
238 if (*bp == '\0')
239 continue;
240 bp = cp;
241 for (;;) {
242 if (!(cp = strsep(&bp, ",")))
243 break;
244 ukey.ue_line = cp;
245 if ((ue = RB_FIND(user_name_tree, env->sc_user_names_t,
246 &ukey)) == NULL) {
247 /* User not found */
248 log_warnx("main: unknown user %s in group %s\n",
249 ukey.ue_line, ge->ge_line);
250 if (bp != NULL)
251 *(bp-1) = ',';
252 continue;
253 }
254 if (bp != NULL)
255 *(bp-1) = ',';
256
257 /* Make sure the new group doesn't equal to the main gid */
258 if (ge->ge_gid == ue->ue_gid)
259 continue;
260
261 len = strlen(ue->ue_netid_line);
262 p = ue->ue_netid_line + len;
263
264 if ((snprintf(p, LINE_WIDTH-len-1, ",%d",
265 ge->ge_gid)) >= (int)(LINE_WIDTH-len)) {
266 return (-1);
267 }
268 }
269 }
270
271 return (0);
272 }
273
274 void
main_end_update(struct env * env)275 main_end_update(struct env *env)
276 {
277 struct userent *ue;
278 struct groupent *ge;
279
280 if (env->update_trashed)
281 return;
282
283 log_debug("updates are over, cleaning up trees now");
284
285 if (main_create_user_groups(env) == -1) {
286 main_trash_update(env);
287 return;
288 }
289
290 if (env->sc_user_names == NULL) {
291 env->sc_user_names = env->sc_user_names_t;
292 env->sc_user_lines = NULL;
293 env->sc_user_names_t = NULL;
294
295 env->sc_group_names = env->sc_group_names_t;
296 env->sc_group_lines = NULL;
297 env->sc_group_names_t = NULL;
298
299 flatten_entries(env);
300 goto make_uids;
301 }
302
303 /*
304 * clean previous tree.
305 */
306 while ((ue = RB_ROOT(env->sc_user_names)) != NULL) {
307 RB_REMOVE(user_name_tree, env->sc_user_names,
308 ue);
309 free(ue->ue_netid_line);
310 free(ue);
311 }
312 free(env->sc_user_names);
313 free(env->sc_user_lines);
314
315 env->sc_user_names = env->sc_user_names_t;
316 env->sc_user_lines = NULL;
317 env->sc_user_names_t = NULL;
318
319 while ((ge = RB_ROOT(env->sc_group_names)) != NULL) {
320 RB_REMOVE(group_name_tree,
321 env->sc_group_names, ge);
322 free(ge);
323 }
324 free(env->sc_group_names);
325 free(env->sc_group_lines);
326
327 env->sc_group_names = env->sc_group_names_t;
328 env->sc_group_lines = NULL;
329 env->sc_group_names_t = NULL;
330
331
332 flatten_entries(env);
333
334 /*
335 * trees are flat now. build up uid, gid and netid trees.
336 */
337
338 make_uids:
339 RB_INIT(&env->sc_user_uids);
340 RB_INIT(&env->sc_group_gids);
341 RB_FOREACH(ue, user_name_tree, env->sc_user_names)
342 RB_INSERT(user_uid_tree,
343 &env->sc_user_uids, ue);
344 RB_FOREACH(ge, group_name_tree, env->sc_group_names)
345 RB_INSERT(group_gid_tree,
346 &env->sc_group_gids, ge);
347
348 }
349
350 void
main_dispatch_client(int fd,short events,void * p)351 main_dispatch_client(int fd, short events, void *p)
352 {
353 int n;
354 int shut = 0;
355 struct env *env = p;
356 struct imsgev *iev = env->sc_iev;
357 struct imsgbuf *ibuf = &iev->ibuf;
358 struct idm_req ir;
359 struct imsg imsg;
360
361 if ((events & (EV_READ | EV_WRITE)) == 0)
362 fatalx("unknown event");
363
364 if (events & EV_READ) {
365 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
366 fatal("imsg_read error");
367 if (n == 0)
368 shut = 1;
369 }
370 if (events & EV_WRITE) {
371 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
372 fatal("msgbuf_write");
373 if (n == 0)
374 shut = 1;
375 goto done;
376 }
377
378 for (;;) {
379 if ((n = imsg_get(ibuf, &imsg)) == -1)
380 fatal("main_dispatch_client: imsg_get error");
381 if (n == 0)
382 break;
383
384 switch (imsg.hdr.type) {
385 case IMSG_START_UPDATE:
386 main_start_update(env);
387 break;
388 case IMSG_PW_ENTRY: {
389 struct userent *ue;
390 size_t len;
391
392 if (env->update_trashed)
393 break;
394
395 (void)memcpy(&ir, imsg.data, sizeof(ir));
396 if ((ue = calloc(1, sizeof(*ue))) == NULL ||
397 (ue->ue_line = strdup(ir.ir_line)) == NULL) {
398 /*
399 * should cancel tree update instead.
400 */
401 fatal("out of memory");
402 }
403 ue->ue_uid = ir.ir_key.ik_uid;
404 len = strlen(ue->ue_line) + 1;
405 ue->ue_line[strcspn(ue->ue_line, ":")] = '\0';
406 if (RB_INSERT(user_name_tree, env->sc_user_names_t,
407 ue) != NULL) { /* dup */
408 free(ue->ue_line);
409 free(ue);
410 } else
411 env->sc_user_line_len += len;
412 break;
413 }
414 case IMSG_GRP_ENTRY: {
415 struct groupent *ge;
416 size_t len;
417
418 if (env->update_trashed)
419 break;
420
421 (void)memcpy(&ir, imsg.data, sizeof(ir));
422 if ((ge = calloc(1, sizeof(*ge))) == NULL ||
423 (ge->ge_line = strdup(ir.ir_line)) == NULL) {
424 /*
425 * should cancel tree update instead.
426 */
427 fatal("out of memory");
428 }
429 ge->ge_gid = ir.ir_key.ik_gid;
430 len = strlen(ge->ge_line) + 1;
431 ge->ge_line[strcspn(ge->ge_line, ":")] = '\0';
432 if (RB_INSERT(group_name_tree, env->sc_group_names_t,
433 ge) != NULL) { /* dup */
434 free(ge->ge_line);
435 free(ge);
436 } else
437 env->sc_group_line_len += len;
438 break;
439 }
440 case IMSG_TRASH_UPDATE:
441 main_trash_update(env);
442 break;
443 case IMSG_END_UPDATE: {
444 main_end_update(env);
445 break;
446 }
447 default:
448 log_debug("main_dispatch_client: unexpected imsg %d",
449 imsg.hdr.type);
450 break;
451 }
452 imsg_free(&imsg);
453 }
454
455 done:
456 if (!shut)
457 imsg_event_add(iev);
458 else {
459 log_debug("king bula sez: ran into dead pipe");
460 event_del(&iev->ev);
461 event_loopexit(NULL);
462 }
463 }
464
465 void
main_configure_client(struct env * env)466 main_configure_client(struct env *env)
467 {
468 struct idm *idm;
469 struct imsgev *iev = env->sc_iev;
470
471 imsg_compose_event(iev, IMSG_CONF_START, 0, 0, -1, env, sizeof(*env));
472 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
473 imsg_compose_event(iev, IMSG_CONF_IDM, 0, 0, -1,
474 idm, sizeof(*idm));
475 }
476 imsg_compose_event(iev, IMSG_CONF_END, 0, 0, -1, NULL, 0);
477 }
478
479 void
main_init_timer(int fd,short event,void * p)480 main_init_timer(int fd, short event, void *p)
481 {
482 struct env *env = p;
483
484 main_configure_client(env);
485 }
486
487 void
purge_config(struct env * env)488 purge_config(struct env *env)
489 {
490 struct idm *idm;
491
492 while ((idm = TAILQ_FIRST(&env->sc_idms)) != NULL) {
493 TAILQ_REMOVE(&env->sc_idms, idm, idm_entry);
494 free(idm);
495 }
496 }
497
498 int
main(int argc,char * argv[])499 main(int argc, char *argv[])
500 {
501 int c;
502 int debug;
503 struct passwd *pw;
504 struct env env;
505 struct event ev_sigint;
506 struct event ev_sigterm;
507 struct event ev_sigchld;
508 struct event ev_sighup;
509 struct event ev_timer;
510 struct timeval tv;
511
512 debug = 0;
513 ypldap_process = PROC_MAIN;
514
515 log_init(1);
516
517 while ((c = getopt(argc, argv, "dD:nf:v")) != -1) {
518 switch (c) {
519 case 'd':
520 debug = 2;
521 break;
522 case 'D':
523 if (cmdline_symset(optarg) < 0)
524 log_warnx("could not parse macro definition %s",
525 optarg);
526 break;
527 case 'n':
528 debug = 2;
529 opts |= YPLDAP_OPT_NOACTION;
530 break;
531 case 'f':
532 conffile = optarg;
533 break;
534 case 'v':
535 opts |= YPLDAP_OPT_VERBOSE;
536 break;
537 default:
538 usage();
539 }
540 }
541
542 argc -= optind;
543 argv += optind;
544
545 if (argc)
546 usage();
547
548 RB_INIT(&env.sc_user_uids);
549 RB_INIT(&env.sc_group_gids);
550
551 if (parse_config(&env, conffile, opts))
552 exit(1);
553 if (opts & YPLDAP_OPT_NOACTION) {
554 fprintf(stderr, "configuration OK\n");
555 exit(0);
556 }
557
558 if (geteuid())
559 errx(1, "need root privileges");
560
561 log_init(debug);
562
563 if (!debug) {
564 if (daemon(1, 0) == -1)
565 err(1, "failed to daemonize");
566 }
567
568 log_info("startup%s", (debug > 1)?" [debug mode]":"");
569
570 if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, PF_UNSPEC,
571 pipe_main2client) == -1)
572 fatal("socketpair");
573
574 client_pid = ldapclient(pipe_main2client);
575
576 setproctitle("parent");
577 event_init();
578
579 signal_set(&ev_sigint, SIGINT, main_sig_handler, &env);
580 signal_set(&ev_sigterm, SIGTERM, main_sig_handler, &env);
581 signal_set(&ev_sighup, SIGHUP, main_sig_handler, &env);
582 signal_set(&ev_sigchld, SIGCHLD, main_sig_handler, &env);
583 signal_add(&ev_sigint, NULL);
584 signal_add(&ev_sigterm, NULL);
585 signal_add(&ev_sighup, NULL);
586 signal_add(&ev_sigchld, NULL);
587
588 close(pipe_main2client[1]);
589 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
590 fatal(NULL);
591 imsg_init(&env.sc_iev->ibuf, pipe_main2client[0]);
592 env.sc_iev->handler = main_dispatch_client;
593
594 env.sc_iev->events = EV_READ;
595 env.sc_iev->data = &env;
596 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
597 env.sc_iev->handler, &env);
598 event_add(&env.sc_iev->ev, NULL);
599
600 yp_init(&env);
601
602 if ((pw = getpwnam(YPLDAP_USER)) == NULL)
603 fatal("getpwnam");
604
605 #ifndef DEBUG
606 if (setgroups(1, &pw->pw_gid) ||
607 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
608 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
609 fatal("cannot drop privileges");
610 #else
611 #warning disabling privilege revocation in debug mode
612 #endif
613
614 memset(&tv, 0, sizeof(tv));
615 evtimer_set(&ev_timer, main_init_timer, &env);
616 evtimer_add(&ev_timer, &tv);
617
618 yp_enable_events();
619 event_dispatch();
620 main_shutdown();
621
622 return (0);
623 }
624
625 void
imsg_event_add(struct imsgev * iev)626 imsg_event_add(struct imsgev *iev)
627 {
628 if (iev->handler == NULL) {
629 imsg_flush(&iev->ibuf);
630 return;
631 }
632
633 iev->events = EV_READ;
634 if (iev->ibuf.w.queued)
635 iev->events |= EV_WRITE;
636
637 event_del(&iev->ev);
638 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
639 event_add(&iev->ev, NULL);
640 }
641
642 int
imsg_compose_event(struct imsgev * iev,u_int16_t type,u_int32_t peerid,pid_t pid,int fd,void * data,u_int16_t datalen)643 imsg_compose_event(struct imsgev *iev, u_int16_t type, u_int32_t peerid,
644 pid_t pid, int fd, void *data, u_int16_t datalen)
645 {
646 int ret;
647
648 if ((ret = imsg_compose(&iev->ibuf, type, peerid,
649 pid, fd, data, datalen)) != -1)
650 imsg_event_add(iev);
651 return (ret);
652 }
653