1 /* $OpenBSD: ypldap.c,v 1.16 2015/11/02 10:06:06 jmatthew Exp $ */
2
3 /*
4 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <sys/types.h>
20 #include <sys/param.h>
21 #include <sys/queue.h>
22 #include <sys/socket.h>
23 #include <sys/signal.h>
24 #include <sys/tree.h>
25 #include <sys/wait.h>
26
27 #include <netinet/in.h>
28 #include <arpa/inet.h>
29
30 #include <err.h>
31 #include <errno.h>
32 #include <event.h>
33 #include <unistd.h>
34 #include <pwd.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <limits.h>
39
40 #include "ypldap.h"
41
42 enum ypldap_process_type ypldap_process;
43
44 __dead2 void usage(void);
45 int check_child(pid_t, const char *);
46 void main_sig_handler(int, short, void *);
47 void main_shutdown(void);
48 void main_dispatch_client(int, short, void *);
49 void main_configure_client(struct env *);
50 void main_init_timer(int, short, void *);
51 void main_start_update(struct env *);
52 void main_trash_update(struct env *);
53 void main_end_update(struct env *);
54 int main_create_user_groups(struct env *);
55 void purge_config(struct env *);
56 void reconfigure(struct env *);
57
58 int pipe_main2client[2];
59
60 pid_t client_pid = 0;
61 char *conffile = YPLDAP_CONF_FILE;
62 int opts = 0;
63
64 void
usage(void)65 usage(void)
66 {
67 extern const char *__progname;
68
69 fprintf(stderr, "usage: %s [-dnv] [-D macro=value] [-f file]\n",
70 __progname);
71 exit(1);
72 }
73
74 int
check_child(pid_t pid,const char * pname)75 check_child(pid_t pid, const char *pname)
76 {
77 int status;
78
79 if (waitpid(pid, &status, WNOHANG) > 0) {
80 if (WIFEXITED(status)) {
81 log_warnx("check_child: lost child %s exited", pname);
82 return (1);
83 }
84 if (WIFSIGNALED(status)) {
85 log_warnx("check_child: lost child %s terminated; "
86 "signal %d", pname, WTERMSIG(status));
87 return (1);
88 }
89 }
90 return (0);
91 }
92
93 /* ARGUSED */
94 void
main_sig_handler(int sig,short event,void * p)95 main_sig_handler(int sig, short event, void *p)
96 {
97 int die = 0;
98
99 switch (sig) {
100 case SIGTERM:
101 case SIGINT:
102 die = 1;
103 /* FALLTHROUGH */
104 case SIGCHLD:
105 if (check_child(client_pid, "ldap client")) {
106 client_pid = 0;
107 die = 1;
108 }
109 if (die)
110 main_shutdown();
111 break;
112 case SIGHUP:
113 /* reconfigure */
114 break;
115 default:
116 fatalx("unexpected signal");
117 }
118 }
119
120 void
main_shutdown(void)121 main_shutdown(void)
122 {
123 _exit(0);
124 }
125
126 void
main_start_update(struct env * env)127 main_start_update(struct env *env)
128 {
129 env->update_trashed = 0;
130
131 log_debug("starting directory update");
132 env->sc_user_line_len = 0;
133 env->sc_group_line_len = 0;
134 if ((env->sc_user_names_t = calloc(1,
135 sizeof(*env->sc_user_names_t))) == NULL ||
136 (env->sc_group_names_t = calloc(1,
137 sizeof(*env->sc_group_names_t))) == NULL)
138 fatal(NULL);
139 RB_INIT(env->sc_user_names_t);
140 RB_INIT(env->sc_group_names_t);
141 }
142
143 /*
144 * XXX: Currently this function should only be called when updating is
145 * finished. A notification should be sent to ldapclient that it should stop
146 * sending new pwd/grp entries before it can be called from different places.
147 */
148 void
main_trash_update(struct env * env)149 main_trash_update(struct env *env)
150 {
151 struct userent *ue;
152 struct groupent *ge;
153
154 env->update_trashed = 1;
155
156 while ((ue = RB_ROOT(env->sc_user_names_t)) != NULL) {
157 RB_REMOVE(user_name_tree,
158 env->sc_user_names_t, ue);
159 free(ue->ue_line);
160 free(ue->ue_netid_line);
161 free(ue);
162 }
163 free(env->sc_user_names_t);
164 env->sc_user_names_t = NULL;
165 while ((ge = RB_ROOT(env->sc_group_names_t))
166 != NULL) {
167 RB_REMOVE(group_name_tree,
168 env->sc_group_names_t, ge);
169 free(ge->ge_line);
170 free(ge);
171 }
172 free(env->sc_group_names_t);
173 env->sc_group_names_t = NULL;
174 }
175
176 int
main_create_user_groups(struct env * env)177 main_create_user_groups(struct env *env)
178 {
179 struct userent *ue;
180 struct userent ukey;
181 struct groupent *ge;
182 gid_t pw_gid;
183 char *bp, *cp;
184 char *p;
185 const char *errstr = NULL;
186 size_t len;
187
188 RB_FOREACH(ue, user_name_tree, env->sc_user_names_t) {
189 bp = cp = ue->ue_line;
190
191 /* name */
192 bp += strlen(bp) + 1;
193
194 /* password */
195 bp += strcspn(bp, ":") + 1;
196
197 /* uid */
198 bp += strcspn(bp, ":") + 1;
199
200 /* gid */
201 bp[strcspn(bp, ":")] = '\0';
202
203 pw_gid = (gid_t)strtonum(bp, 0, GID_MAX, &errstr);
204 if (errstr) {
205 log_warnx("main: failed to parse gid for uid: %d\n", ue->ue_uid);
206 return (-1);
207 }
208
209 /* bring gid column back to its proper state */
210 bp[strlen(bp)] = ':';
211
212 if ((ue->ue_netid_line = calloc(1, LINE_WIDTH)) == NULL) {
213 return (-1);
214 }
215
216 if (snprintf(ue->ue_netid_line, LINE_WIDTH-1, "%d:%d", ue->ue_uid, pw_gid) >= LINE_WIDTH) {
217
218 return (-1);
219 }
220
221 ue->ue_gid = pw_gid;
222 }
223
224 RB_FOREACH(ge, group_name_tree, env->sc_group_names_t) {
225 bp = cp = ge->ge_line;
226
227 /* name */
228 bp += strlen(bp) + 1;
229
230 /* password */
231 bp += strcspn(bp, ":") + 1;
232
233 /* gid */
234 bp += strcspn(bp, ":") + 1;
235
236 cp = bp;
237 if (*bp == '\0')
238 continue;
239 bp = cp;
240 for (;;) {
241 if (!(cp = strsep(&bp, ",")))
242 break;
243 ukey.ue_line = cp;
244 if ((ue = RB_FIND(user_name_tree, env->sc_user_names_t,
245 &ukey)) == NULL) {
246 /* User not found */
247 log_warnx("main: unknown user %s in group %s\n",
248 ukey.ue_line, ge->ge_line);
249 if (bp != NULL)
250 *(bp-1) = ',';
251 continue;
252 }
253 if (bp != NULL)
254 *(bp-1) = ',';
255
256 /* Make sure the new group doesn't equal to the main gid */
257 if (ge->ge_gid == ue->ue_gid)
258 continue;
259
260 len = strlen(ue->ue_netid_line);
261 p = ue->ue_netid_line + len;
262
263 if ((snprintf(p, LINE_WIDTH-len-1, ",%d",
264 ge->ge_gid)) >= (int)(LINE_WIDTH-len)) {
265 return (-1);
266 }
267 }
268 }
269
270 return (0);
271 }
272
273 void
main_end_update(struct env * env)274 main_end_update(struct env *env)
275 {
276 struct userent *ue;
277 struct groupent *ge;
278
279 if (env->update_trashed)
280 return;
281
282 log_debug("updates are over, cleaning up trees now");
283
284 if (main_create_user_groups(env) == -1) {
285 main_trash_update(env);
286 return;
287 }
288
289 if (env->sc_user_names == NULL) {
290 env->sc_user_names = env->sc_user_names_t;
291 env->sc_user_lines = NULL;
292 env->sc_user_names_t = NULL;
293
294 env->sc_group_names = env->sc_group_names_t;
295 env->sc_group_lines = NULL;
296 env->sc_group_names_t = NULL;
297
298 flatten_entries(env);
299 goto make_uids;
300 }
301
302 /*
303 * clean previous tree.
304 */
305 while ((ue = RB_ROOT(env->sc_user_names)) != NULL) {
306 RB_REMOVE(user_name_tree, env->sc_user_names,
307 ue);
308 free(ue->ue_netid_line);
309 free(ue);
310 }
311 free(env->sc_user_names);
312 free(env->sc_user_lines);
313
314 env->sc_user_names = env->sc_user_names_t;
315 env->sc_user_lines = NULL;
316 env->sc_user_names_t = NULL;
317
318 while ((ge = RB_ROOT(env->sc_group_names)) != NULL) {
319 RB_REMOVE(group_name_tree,
320 env->sc_group_names, ge);
321 free(ge);
322 }
323 free(env->sc_group_names);
324 free(env->sc_group_lines);
325
326 env->sc_group_names = env->sc_group_names_t;
327 env->sc_group_lines = NULL;
328 env->sc_group_names_t = NULL;
329
330
331 flatten_entries(env);
332
333 /*
334 * trees are flat now. build up uid, gid and netid trees.
335 */
336
337 make_uids:
338 RB_INIT(&env->sc_user_uids);
339 RB_INIT(&env->sc_group_gids);
340 RB_FOREACH(ue, user_name_tree, env->sc_user_names)
341 RB_INSERT(user_uid_tree,
342 &env->sc_user_uids, ue);
343 RB_FOREACH(ge, group_name_tree, env->sc_group_names)
344 RB_INSERT(group_gid_tree,
345 &env->sc_group_gids, ge);
346
347 }
348
349 void
main_dispatch_client(int fd,short events,void * p)350 main_dispatch_client(int fd, short events, void *p)
351 {
352 int n;
353 int shut = 0;
354 struct env *env = p;
355 struct imsgev *iev = env->sc_iev;
356 struct imsgbuf *ibuf = &iev->ibuf;
357 struct idm_req ir;
358 struct imsg imsg;
359
360 if ((events & (EV_READ | EV_WRITE)) == 0)
361 fatalx("unknown event");
362
363 if (events & EV_READ) {
364 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
365 fatal("imsg_read error");
366 if (n == 0)
367 shut = 1;
368 }
369 if (events & EV_WRITE) {
370 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
371 fatal("msgbuf_write");
372 if (n == 0)
373 shut = 1;
374 goto done;
375 }
376
377 for (;;) {
378 if ((n = imsg_get(ibuf, &imsg)) == -1)
379 fatal("main_dispatch_client: imsg_get error");
380 if (n == 0)
381 break;
382
383 switch (imsg.hdr.type) {
384 case IMSG_START_UPDATE:
385 main_start_update(env);
386 break;
387 case IMSG_PW_ENTRY: {
388 struct userent *ue;
389 size_t len;
390
391 if (env->update_trashed)
392 break;
393
394 (void)memcpy(&ir, imsg.data, sizeof(ir));
395 if ((ue = calloc(1, sizeof(*ue))) == NULL ||
396 (ue->ue_line = strdup(ir.ir_line)) == NULL) {
397 /*
398 * should cancel tree update instead.
399 */
400 fatal("out of memory");
401 }
402 ue->ue_uid = ir.ir_key.ik_uid;
403 len = strlen(ue->ue_line) + 1;
404 ue->ue_line[strcspn(ue->ue_line, ":")] = '\0';
405 if (RB_INSERT(user_name_tree, env->sc_user_names_t,
406 ue) != NULL) { /* dup */
407 free(ue->ue_line);
408 free(ue);
409 } else
410 env->sc_user_line_len += len;
411 break;
412 }
413 case IMSG_GRP_ENTRY: {
414 struct groupent *ge;
415 size_t len;
416
417 if (env->update_trashed)
418 break;
419
420 (void)memcpy(&ir, imsg.data, sizeof(ir));
421 if ((ge = calloc(1, sizeof(*ge))) == NULL ||
422 (ge->ge_line = strdup(ir.ir_line)) == NULL) {
423 /*
424 * should cancel tree update instead.
425 */
426 fatal("out of memory");
427 }
428 ge->ge_gid = ir.ir_key.ik_gid;
429 len = strlen(ge->ge_line) + 1;
430 ge->ge_line[strcspn(ge->ge_line, ":")] = '\0';
431 if (RB_INSERT(group_name_tree, env->sc_group_names_t,
432 ge) != NULL) { /* dup */
433 free(ge->ge_line);
434 free(ge);
435 } else
436 env->sc_group_line_len += len;
437 break;
438 }
439 case IMSG_TRASH_UPDATE:
440 main_trash_update(env);
441 break;
442 case IMSG_END_UPDATE: {
443 main_end_update(env);
444 break;
445 }
446 default:
447 log_debug("main_dispatch_client: unexpected imsg %d",
448 imsg.hdr.type);
449 break;
450 }
451 imsg_free(&imsg);
452 }
453
454 done:
455 if (!shut)
456 imsg_event_add(iev);
457 else {
458 log_debug("king bula sez: ran into dead pipe");
459 event_del(&iev->ev);
460 event_loopexit(NULL);
461 }
462 }
463
464 void
main_configure_client(struct env * env)465 main_configure_client(struct env *env)
466 {
467 struct idm *idm;
468 struct imsgev *iev = env->sc_iev;
469
470 imsg_compose_event(iev, IMSG_CONF_START, 0, 0, -1, env, sizeof(*env));
471 TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
472 imsg_compose_event(iev, IMSG_CONF_IDM, 0, 0, -1,
473 idm, sizeof(*idm));
474 }
475 imsg_compose_event(iev, IMSG_CONF_END, 0, 0, -1, NULL, 0);
476 }
477
478 void
main_init_timer(int fd,short event,void * p)479 main_init_timer(int fd, short event, void *p)
480 {
481 struct env *env = p;
482
483 main_configure_client(env);
484 }
485
486 void
purge_config(struct env * env)487 purge_config(struct env *env)
488 {
489 struct idm *idm;
490
491 while ((idm = TAILQ_FIRST(&env->sc_idms)) != NULL) {
492 TAILQ_REMOVE(&env->sc_idms, idm, idm_entry);
493 free(idm);
494 }
495 }
496
497 int
main(int argc,char * argv[])498 main(int argc, char *argv[])
499 {
500 int c;
501 int debug;
502 struct passwd *pw;
503 struct env env;
504 struct event ev_sigint;
505 struct event ev_sigterm;
506 struct event ev_sigchld;
507 struct event ev_sighup;
508 struct event ev_timer;
509 struct timeval tv;
510
511 debug = 0;
512 ypldap_process = PROC_MAIN;
513
514 log_init(1);
515
516 while ((c = getopt(argc, argv, "dD:nf:v")) != -1) {
517 switch (c) {
518 case 'd':
519 debug = 2;
520 break;
521 case 'D':
522 if (cmdline_symset(optarg) < 0)
523 log_warnx("could not parse macro definition %s",
524 optarg);
525 break;
526 case 'n':
527 debug = 2;
528 opts |= YPLDAP_OPT_NOACTION;
529 break;
530 case 'f':
531 conffile = optarg;
532 break;
533 case 'v':
534 opts |= YPLDAP_OPT_VERBOSE;
535 break;
536 default:
537 usage();
538 }
539 }
540
541 argc -= optind;
542 argv += optind;
543
544 if (argc)
545 usage();
546
547 RB_INIT(&env.sc_user_uids);
548 RB_INIT(&env.sc_group_gids);
549
550 if (parse_config(&env, conffile, opts))
551 exit(1);
552 if (opts & YPLDAP_OPT_NOACTION) {
553 fprintf(stderr, "configuration OK\n");
554 exit(0);
555 }
556
557 if (geteuid())
558 errx(1, "need root privileges");
559
560 log_init(debug);
561
562 if (!debug) {
563 if (daemon(1, 0) == -1)
564 err(1, "failed to daemonize");
565 }
566
567 log_info("startup%s", (debug > 1)?" [debug mode]":"");
568
569 if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, PF_UNSPEC,
570 pipe_main2client) == -1)
571 fatal("socketpair");
572
573 client_pid = ldapclient(pipe_main2client);
574
575 setproctitle("parent");
576 event_init();
577
578 signal_set(&ev_sigint, SIGINT, main_sig_handler, &env);
579 signal_set(&ev_sigterm, SIGTERM, main_sig_handler, &env);
580 signal_set(&ev_sighup, SIGHUP, main_sig_handler, &env);
581 signal_set(&ev_sigchld, SIGCHLD, main_sig_handler, &env);
582 signal_add(&ev_sigint, NULL);
583 signal_add(&ev_sigterm, NULL);
584 signal_add(&ev_sighup, NULL);
585 signal_add(&ev_sigchld, NULL);
586
587 close(pipe_main2client[1]);
588 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
589 fatal(NULL);
590 imsg_init(&env.sc_iev->ibuf, pipe_main2client[0]);
591 env.sc_iev->handler = main_dispatch_client;
592
593 env.sc_iev->events = EV_READ;
594 env.sc_iev->data = &env;
595 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
596 env.sc_iev->handler, &env);
597 event_add(&env.sc_iev->ev, NULL);
598
599 yp_init(&env);
600
601 if ((pw = getpwnam(YPLDAP_USER)) == NULL)
602 fatal("getpwnam");
603
604 #ifndef DEBUG
605 if (setgroups(1, &pw->pw_gid) ||
606 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
607 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
608 fatal("cannot drop privileges");
609 #else
610 #warning disabling privilege revocation in debug mode
611 #endif
612
613 memset(&tv, 0, sizeof(tv));
614 evtimer_set(&ev_timer, main_init_timer, &env);
615 evtimer_add(&ev_timer, &tv);
616
617 yp_enable_events();
618 event_dispatch();
619 main_shutdown();
620
621 return (0);
622 }
623
624 void
imsg_event_add(struct imsgev * iev)625 imsg_event_add(struct imsgev *iev)
626 {
627 if (iev->handler == NULL) {
628 imsg_flush(&iev->ibuf);
629 return;
630 }
631
632 iev->events = EV_READ;
633 if (iev->ibuf.w.queued)
634 iev->events |= EV_WRITE;
635
636 event_del(&iev->ev);
637 event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
638 event_add(&iev->ev, NULL);
639 }
640
641 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)642 imsg_compose_event(struct imsgev *iev, u_int16_t type, u_int32_t peerid,
643 pid_t pid, int fd, void *data, u_int16_t datalen)
644 {
645 int ret;
646
647 if ((ret = imsg_compose(&iev->ibuf, type, peerid,
648 pid, fd, data, datalen)) != -1)
649 imsg_event_add(iev);
650 return (ret);
651 }
652