xref: /openbsd/usr.sbin/ldapd/ldapd.c (revision fc61954a)
1 /*	$OpenBSD: ldapd.c,v 1.20 2016/05/01 00:32:37 jmatthew Exp $ */
2 
3 /*
4  * Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se>
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/queue.h>
20 #include <sys/stat.h>
21 #include <sys/un.h>
22 #include <sys/types.h>
23 #include <sys/wait.h>
24 
25 #include <assert.h>
26 #include <bsd_auth.h>
27 #include <ctype.h>
28 #include <err.h>
29 #include <errno.h>
30 #include <event.h>
31 #include <fcntl.h>
32 #include <login_cap.h>
33 #include <signal.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <time.h>
38 #include <unistd.h>
39 
40 #include "ldapd.h"
41 
42 void		 usage(void);
43 void		 ldapd_sig_handler(int fd, short why, void *data);
44 void		 ldapd_sigchld_handler(int sig, short why, void *data);
45 static void	 ldapd_imsgev(struct imsgev *iev, int code, struct imsg *imsg);
46 static void	 ldapd_needfd(struct imsgev *iev);
47 static void	 ldapd_auth_request(struct imsgev *iev, struct imsg *imsg);
48 static void	 ldapd_open_request(struct imsgev *iev, struct imsg *imsg);
49 static void	 ldapd_log_verbose(struct imsg *imsg);
50 static void	 ldapd_cleanup(char *);
51 
52 struct ldapd_stats	 stats;
53 pid_t			 ldape_pid;
54 const char		*datadir = DATADIR;
55 
56 void
57 usage(void)
58 {
59 	extern char	*__progname;
60 
61 	fprintf(stderr, "usage: %s [-dnv] [-D macro=value] "
62 	    "[-f file] [-r directory] [-s file]\n", __progname);
63 	exit(1);
64 }
65 
66 void
67 ldapd_sig_handler(int sig, short why, void *data)
68 {
69 	log_info("ldapd: got signal %d", sig);
70 	if (sig == SIGINT || sig == SIGTERM)
71 		event_loopexit(NULL);
72 }
73 
74 void
75 ldapd_sigchld_handler(int sig, short why, void *data)
76 {
77 	pid_t		 pid;
78 	int		 status;
79 
80 	while ((pid = waitpid(WAIT_ANY, &status, WNOHANG)) != 0) {
81 		if (pid == -1) {
82 			if (errno == EINTR)
83 				continue;
84 			if (errno != ECHILD)
85 				log_warn("waitpid");
86 			break;
87 		}
88 
89 		if (WIFEXITED(status))
90 			log_debug("child %d exited with status %d",
91 			    pid, WEXITSTATUS(status));
92 		else if (WIFSIGNALED(status))
93 			log_debug("child %d exited due to signal %d",
94 			    pid, WTERMSIG(status));
95 		else
96 			log_debug("child %d terminated abnormally", pid);
97 
98 		if (pid == ldape_pid) {
99 			log_info("ldapd: lost ldap server");
100 			event_loopexit(NULL);
101 			break;
102 		}
103 	}
104 }
105 
106 int
107 main(int argc, char *argv[])
108 {
109 	int			 c;
110 	int			 debug = 0, verbose = 0;
111 	int			 configtest = 0, skip_chroot = 0;
112 	int			 pipe_parent2ldap[2];
113 	char			*conffile = CONFFILE;
114 	char			*csockpath = LDAPD_SOCKET;
115 	struct passwd		*pw = NULL;
116 	struct imsgev		*iev_ldape;
117 	struct event		 ev_sigint;
118 	struct event		 ev_sigterm;
119 	struct event		 ev_sigchld;
120 	struct event		 ev_sighup;
121 	struct stat		 sb;
122 
123 	log_init(1);		/* log to stderr until daemonized */
124 
125 	while ((c = getopt(argc, argv, "dhvD:f:nr:s:")) != -1) {
126 		switch (c) {
127 		case 'd':
128 			debug = 1;
129 			break;
130 		case 'D':
131 			if (cmdline_symset(optarg) < 0) {
132 				warnx("could not parse macro definition %s",
133 				    optarg);
134 			}
135 			break;
136 		case 'f':
137 			conffile = optarg;
138 			break;
139 		case 'h':
140 			usage();
141 			/* NOTREACHED */
142 		case 'n':
143 			configtest = 1;
144 			break;
145 		case 'r':
146 			datadir = optarg;
147 			break;
148 		case 's':
149 			csockpath = optarg;
150 			break;
151 		case 'v':
152 			verbose++;
153 			break;
154 		default:
155 			usage();
156 			/* NOTREACHED */
157 		}
158 	}
159 
160 	argc -= optind;
161 	if (argc > 0)
162 		usage();
163 
164 	log_verbose(verbose);
165 	stats.started_at = time(0);
166 	tls_init();
167 
168 	if (parse_config(conffile) != 0)
169 		exit(2);
170 
171 	if (configtest) {
172 		fprintf(stderr, "configuration ok\n");
173 		exit(0);
174 	}
175 
176 	if (geteuid()) {
177 		if (!debug)
178 			errx(1, "need root privileges");
179 		skip_chroot = 1;
180 	}
181 
182 	if (stat(datadir, &sb) == -1)
183 		err(1, "%s", datadir);
184 	if (!S_ISDIR(sb.st_mode))
185 		errx(1, "%s is not a directory", datadir);
186 
187 	if (!skip_chroot && (pw = getpwnam(LDAPD_USER)) == NULL)
188 		err(1, "%s", LDAPD_USER);
189 
190 	if (!debug) {
191 		if (daemon(1, 0) == -1)
192 			err(1, "failed to daemonize");
193 	}
194 
195 	log_init(debug);
196 	log_info("startup");
197 
198 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, PF_UNSPEC,
199 	    pipe_parent2ldap) != 0)
200 		fatal("socketpair");
201 
202 	ldape_pid = ldape(pw, csockpath, pipe_parent2ldap);
203 
204 	setproctitle("auth");
205 	event_init();
206 
207 	signal_set(&ev_sigint, SIGINT, ldapd_sig_handler, NULL);
208 	signal_set(&ev_sigterm, SIGTERM, ldapd_sig_handler, NULL);
209 	signal_set(&ev_sigchld, SIGCHLD, ldapd_sigchld_handler, NULL);
210 	signal_set(&ev_sighup, SIGHUP, ldapd_sig_handler, NULL);
211 	signal_add(&ev_sigint, NULL);
212 	signal_add(&ev_sigterm, NULL);
213 	signal_add(&ev_sigchld, NULL);
214 	signal_add(&ev_sighup, NULL);
215 	signal(SIGPIPE, SIG_IGN);
216 
217 	close(pipe_parent2ldap[1]);
218 
219 	if ((iev_ldape = calloc(1, sizeof(struct imsgev))) == NULL)
220 		fatal("calloc");
221 	imsgev_init(iev_ldape, pipe_parent2ldap[0], NULL, ldapd_imsgev,
222 	    ldapd_needfd);
223 
224 	if (pledge("stdio rpath wpath cpath getpw sendfd proc exec",
225 	    NULL) == -1)
226 		err(1, "pledge");
227 
228 	event_dispatch();
229 
230 	ldapd_cleanup(csockpath);
231 	log_debug("ldapd: exiting");
232 
233 	return 0;
234 }
235 
236 static void
237 ldapd_cleanup(char * csockpath)
238 {
239 	struct listener		*l;
240 	struct sockaddr_un	*sun = NULL;
241 
242 	/* Remove control socket. */
243 	(void)unlink(csockpath);
244 
245 	/* Remove unix listening sockets. */
246 	TAILQ_FOREACH(l, &conf->listeners, entry) {
247 		if (l->ss.ss_family == AF_UNIX) {
248 			sun = (struct sockaddr_un *)&l->ss;
249 			log_info("ldapd: removing unix socket %s", sun->sun_path);
250 			(void)unlink(sun->sun_path);
251 		}
252 	}
253 }
254 
255 static void
256 ldapd_imsgev(struct imsgev *iev, int code, struct imsg *imsg)
257 {
258 	switch (code) {
259 	case IMSGEV_IMSG:
260 		log_debug("%s: got imsg %d on fd %d",
261 		    __func__, imsg->hdr.type, iev->ibuf.fd);
262 		switch (imsg->hdr.type) {
263 		case IMSG_LDAPD_AUTH:
264 			ldapd_auth_request(iev, imsg);
265 			break;
266 		case IMSG_CTL_LOG_VERBOSE:
267 			ldapd_log_verbose(imsg);
268 			break;
269 		case IMSG_LDAPD_OPEN:
270 			ldapd_open_request(iev, imsg);
271 			break;
272 		default:
273 			log_debug("%s: unexpected imsg %d",
274 			    __func__, imsg->hdr.type);
275 			break;
276 		}
277 		break;
278 	case IMSGEV_EREAD:
279 	case IMSGEV_EWRITE:
280 	case IMSGEV_EIMSG:
281 		fatal("imsgev read/write error");
282 		break;
283 	case IMSGEV_DONE:
284 		event_loopexit(NULL);
285 		break;
286 	}
287 }
288 
289 static void
290 ldapd_needfd(struct imsgev *iev)
291 {
292 	fatal("should never need an fd for parent messages");
293 }
294 
295 static int
296 ldapd_auth_classful(char *name, char *password)
297 {
298 	login_cap_t		*lc = NULL;
299 	char			*class = NULL, *style = NULL;
300 	auth_session_t		*as;
301 
302 	if ((class = strchr(name, '#')) == NULL) {
303 		log_debug("regular auth");
304 		return auth_userokay(name, NULL, "auth-ldap", password);
305 	}
306 	*class++ = '\0';
307 
308 	if ((lc = login_getclass(class)) == NULL) {
309 		log_debug("login_getclass(%s) for [%s] failed", class, name);
310 		return 0;
311 	}
312 	if ((style = login_getstyle(lc, style, "auth-ldap")) == NULL) {
313 		log_debug("login_getstyle() for [%s] failed", name);
314 		login_close(lc);
315 		return 0;
316 	}
317 	if (password) {
318 		if ((as = auth_open()) == NULL) {
319 			login_close(lc);
320 			return 0;
321 		}
322 		auth_setitem(as, AUTHV_SERVICE, "response");
323 		auth_setdata(as, "", 1);
324 		auth_setdata(as, password, strlen(password) + 1);
325 		explicit_bzero(password, strlen(password));
326 	} else
327 		as = NULL;
328 
329 	as = auth_verify(as, style, name, lc->lc_class, (char *)NULL);
330 	login_close(lc);
331 	return (as != NULL ? auth_close(as) : 0);
332 }
333 
334 static void
335 ldapd_auth_request(struct imsgev *iev, struct imsg *imsg)
336 {
337 	struct auth_req		*areq = imsg->data;
338 	struct auth_res		 ares;
339 
340 	if (imsg->hdr.len != sizeof(*areq) + IMSG_HEADER_SIZE)
341 		fatal("invalid size of auth request");
342 
343 	/* make sure name and password are null-terminated */
344 	areq->name[sizeof(areq->name) - 1] = '\0';
345 	areq->password[sizeof(areq->password) - 1] = '\0';
346 
347 	log_debug("authenticating [%s]", areq->name);
348 	ares.ok = ldapd_auth_classful(areq->name, areq->password);
349 	ares.fd = areq->fd;
350 	ares.msgid = areq->msgid;
351 	memset(areq, 0, sizeof(*areq));
352 	imsgev_compose(iev, IMSG_LDAPD_AUTH_RESULT, 0, 0, -1, &ares,
353 	    sizeof(ares));
354 }
355 
356 static void
357 ldapd_log_verbose(struct imsg *imsg)
358 {
359 	int	 verbose;
360 
361 	if (imsg->hdr.len != sizeof(verbose) + IMSG_HEADER_SIZE)
362 		fatal("invalid size of log verbose request");
363 
364 	bcopy(imsg->data, &verbose, sizeof(verbose));
365 	log_verbose(verbose);
366 }
367 
368 static void
369 ldapd_open_request(struct imsgev *iev, struct imsg *imsg)
370 {
371 	struct open_req		*oreq = imsg->data;
372 	int			 oflags, fd;
373 
374 	if (imsg->hdr.len != sizeof(*oreq) + IMSG_HEADER_SIZE)
375 		fatal("invalid size of open request");
376 
377 	/* make sure path is null-terminated */
378 	oreq->path[PATH_MAX] = '\0';
379 
380 	if (strncmp(oreq->path, datadir, strlen(datadir)) != 0) {
381 		log_warnx("refusing to open file %s", oreq->path);
382 		fatal("ldape sent invalid open request");
383 	}
384 
385 	if (oreq->rdonly)
386 		oflags = O_RDONLY;
387 	else
388 		oflags = O_RDWR | O_CREAT | O_APPEND;
389 
390 	log_debug("opening [%s]", oreq->path);
391 	fd = open(oreq->path, oflags | O_NOFOLLOW, 0600);
392 	if (fd == -1)
393 		log_warn("%s", oreq->path);
394 
395 	imsgev_compose(iev, IMSG_LDAPD_OPEN_RESULT, 0, 0, fd, oreq,
396 	    sizeof(*oreq));
397 }
398 
399