xref: /openbsd-src/usr.sbin/ldapd/ldapd.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*	$OpenBSD: ldapd.c,v 1.10 2013/11/02 13:31:51 deraadt 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/types.h>
21 #include <sys/wait.h>
22 
23 #include <assert.h>
24 #include <bsd_auth.h>
25 #include <ctype.h>
26 #include <err.h>
27 #include <errno.h>
28 #include <event.h>
29 #include <fcntl.h>
30 #include <login_cap.h>
31 #include <signal.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <time.h>
36 #include <unistd.h>
37 
38 #include "ldapd.h"
39 
40 void		 usage(void);
41 void		 ldapd_sig_handler(int fd, short why, void *data);
42 void		 ldapd_sigchld_handler(int sig, short why, void *data);
43 static void	 ldapd_imsgev(struct imsgev *iev, int code, struct imsg *imsg);
44 static void	 ldapd_needfd(struct imsgev *iev);
45 static void	 ldapd_auth_request(struct imsgev *iev, struct imsg *imsg);
46 static void	 ldapd_open_request(struct imsgev *iev, struct imsg *imsg);
47 static void	 ldapd_log_verbose(struct imsg *imsg);
48 
49 struct ldapd_stats	 stats;
50 pid_t			 ldape_pid;
51 
52 void
53 usage(void)
54 {
55 	extern char	*__progname;
56 
57 	fprintf(stderr, "usage: %s [-dnv] [-D macro=value] "
58 	    "[-f file] [-s file]\n", __progname);
59 	exit(1);
60 }
61 
62 void
63 ldapd_sig_handler(int sig, short why, void *data)
64 {
65 	log_info("ldapd: got signal %d", sig);
66 	if (sig == SIGINT || sig == SIGTERM)
67 		event_loopexit(NULL);
68 }
69 
70 void
71 ldapd_sigchld_handler(int sig, short why, void *data)
72 {
73 	pid_t		 pid;
74 	int		 status;
75 
76 	while ((pid = waitpid(WAIT_ANY, &status, WNOHANG)) != 0) {
77 		if (pid == -1) {
78 			if (errno == EINTR)
79 				continue;
80 			if (errno != ECHILD)
81 				log_warn("waitpid");
82 			break;
83 		}
84 
85 		if (WIFEXITED(status))
86 			log_debug("child %d exited with status %d",
87 			    pid, WEXITSTATUS(status));
88 		else if (WIFSIGNALED(status))
89 			log_debug("child %d exited due to signal %d",
90 			    pid, WTERMSIG(status));
91 		else
92 			log_debug("child %d terminated abnormally", pid);
93 
94 		if (pid == ldape_pid) {
95 			log_info("ldapd: lost ldap server");
96 			event_loopexit(NULL);
97 			break;
98 		}
99 	}
100 }
101 
102 /* set socket non-blocking */
103 void
104 fd_nonblock(int fd)
105 {
106 	int flags = fcntl(fd, F_GETFL, 0);
107 	int rc = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
108 	if (rc == -1) {
109 		log_warn("failed to set fd %d non-blocking", fd);
110 	}
111 }
112 
113 
114 int
115 main(int argc, char *argv[])
116 {
117 	int			 c;
118 	int			 debug = 0, verbose = 0;
119 	int			 configtest = 0, skip_chroot = 0;
120 	int			 pipe_parent2ldap[2];
121 	char			*conffile = CONFFILE;
122 	char			*csockpath = LDAPD_SOCKET;
123 	struct passwd		*pw = NULL;
124 	struct imsgev		*iev_ldape;
125 	struct event		 ev_sigint;
126 	struct event		 ev_sigterm;
127 	struct event		 ev_sigchld;
128 	struct event		 ev_sighup;
129 
130 	log_init(1);		/* log to stderr until daemonized */
131 
132 	while ((c = getopt(argc, argv, "dhvD:f:ns:")) != -1) {
133 		switch (c) {
134 		case 'd':
135 			debug = 1;
136 			break;
137 		case 'D':
138 			if (cmdline_symset(optarg) < 0) {
139 				warnx("could not parse macro definition %s",
140 				    optarg);
141 			}
142 			break;
143 		case 'f':
144 			conffile = optarg;
145 			break;
146 		case 'h':
147 			usage();
148 			/* NOTREACHED */
149 		case 'n':
150 			configtest = 1;
151 			break;
152 		case 's':
153 			csockpath = optarg;
154 			break;
155 		case 'v':
156 			verbose++;
157 			break;
158 		default:
159 			usage();
160 			/* NOTREACHED */
161 		}
162 	}
163 
164 	argc -= optind;
165 	if (argc > 0)
166 		usage();
167 
168 	log_verbose(verbose);
169 	stats.started_at = time(0);
170 	ssl_init();
171 
172 	if (parse_config(conffile) != 0)
173 		exit(2);
174 
175 	if (configtest) {
176 		fprintf(stderr, "configuration ok\n");
177 		exit(0);
178 	}
179 
180 	if (geteuid()) {
181 		if (!debug)
182 			errx(1, "need root privileges");
183 		skip_chroot = 1;
184 	}
185 
186 	if (!skip_chroot && (pw = getpwnam(LDAPD_USER)) == NULL)
187 		err(1, "%s", LDAPD_USER);
188 
189 	if (!debug) {
190 		if (daemon(1, 0) == -1)
191 			err(1, "failed to daemonize");
192 	}
193 
194 	log_init(debug);
195 	log_info("startup");
196 
197 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipe_parent2ldap) != 0)
198 		fatal("socketpair");
199 
200 	fd_nonblock(pipe_parent2ldap[0]);
201 	fd_nonblock(pipe_parent2ldap[1]);
202 
203 	ldape_pid = ldape(pw, csockpath, pipe_parent2ldap);
204 
205 	setproctitle("auth");
206 	event_init();
207 
208 	signal_set(&ev_sigint, SIGINT, ldapd_sig_handler, NULL);
209 	signal_set(&ev_sigterm, SIGTERM, ldapd_sig_handler, NULL);
210 	signal_set(&ev_sigchld, SIGCHLD, ldapd_sigchld_handler, NULL);
211 	signal_set(&ev_sighup, SIGHUP, ldapd_sig_handler, NULL);
212 	signal_add(&ev_sigint, NULL);
213 	signal_add(&ev_sigterm, NULL);
214 	signal_add(&ev_sigchld, NULL);
215 	signal_add(&ev_sighup, NULL);
216 	signal(SIGPIPE, SIG_IGN);
217 
218 	close(pipe_parent2ldap[1]);
219 
220 	if ((iev_ldape = calloc(1, sizeof(struct imsgev))) == NULL)
221 		fatal("calloc");
222 	imsgev_init(iev_ldape, pipe_parent2ldap[0], NULL, ldapd_imsgev,
223 	    ldapd_needfd);
224 
225 	event_dispatch();
226 	log_debug("ldapd: exiting");
227 
228 	return 0;
229 }
230 
231 static void
232 ldapd_imsgev(struct imsgev *iev, int code, struct imsg *imsg)
233 {
234 	switch (code) {
235 	case IMSGEV_IMSG:
236 		log_debug("%s: got imsg %d on fd %d",
237 		    __func__, imsg->hdr.type, iev->ibuf.fd);
238 		switch (imsg->hdr.type) {
239 		case IMSG_LDAPD_AUTH:
240 			ldapd_auth_request(iev, imsg);
241 			break;
242 		case IMSG_CTL_LOG_VERBOSE:
243 			ldapd_log_verbose(imsg);
244 			break;
245 		case IMSG_LDAPD_OPEN:
246 			ldapd_open_request(iev, imsg);
247 			break;
248 		default:
249 			log_debug("%s: unexpected imsg %d",
250 			    __func__, imsg->hdr.type);
251 			break;
252 		}
253 		break;
254 	case IMSGEV_EREAD:
255 	case IMSGEV_EWRITE:
256 	case IMSGEV_EIMSG:
257 		fatal("imsgev read/write error");
258 		break;
259 	case IMSGEV_DONE:
260 		event_loopexit(NULL);
261 		break;
262 	}
263 }
264 
265 static void
266 ldapd_needfd(struct imsgev *iev)
267 {
268 	fatal("should never need an fd for parent messages");
269 }
270 
271 static int
272 ldapd_auth_classful(char *name, char *password)
273 {
274 	login_cap_t		*lc = NULL;
275 	char			*class = NULL, *style = NULL;
276 	auth_session_t		*as;
277 
278 	if ((class = strchr(name, '#')) == NULL) {
279 		log_debug("regular auth");
280 		return auth_userokay(name, NULL, "auth-ldap", password);
281 	}
282 	*class++ = '\0';
283 
284 	if ((lc = login_getclass(class)) == NULL) {
285 		log_debug("login_getclass(%s) for [%s] failed", class, name);
286 		return 0;
287 	}
288 	if ((style = login_getstyle(lc, style, "auth-ldap")) == NULL) {
289 		log_debug("login_getstyle() for [%s] failed", name);
290 		login_close(lc);
291 		return 0;
292 	}
293 	if (password) {
294 		if ((as = auth_open()) == NULL) {
295 			login_close(lc);
296 			return 0;
297 		}
298 		auth_setitem(as, AUTHV_SERVICE, "response");
299 		auth_setdata(as, "", 1);
300 		auth_setdata(as, password, strlen(password) + 1);
301 		memset(password, 0, strlen(password));
302 	} else
303 		as = NULL;
304 
305 	as = auth_verify(as, style, name, lc->lc_class, (char *)NULL);
306 	login_close(lc);
307 	return (as != NULL ? auth_close(as) : 0);
308 }
309 
310 static void
311 ldapd_auth_request(struct imsgev *iev, struct imsg *imsg)
312 {
313 	struct auth_req		*areq = imsg->data;
314 	struct auth_res		 ares;
315 
316 	if (imsg->hdr.len != sizeof(*areq) + IMSG_HEADER_SIZE)
317 		fatal("invalid size of auth request");
318 
319 	/* make sure name and password are null-terminated */
320 	areq->name[sizeof(areq->name) - 1] = '\0';
321 	areq->password[sizeof(areq->password) - 1] = '\0';
322 
323 	log_debug("authenticating [%s]", areq->name);
324 	ares.ok = ldapd_auth_classful(areq->name, areq->password);
325 	ares.fd = areq->fd;
326 	ares.msgid = areq->msgid;
327 	bzero(areq, sizeof(*areq));
328 	imsgev_compose(iev, IMSG_LDAPD_AUTH_RESULT, 0, 0, -1, &ares,
329 	    sizeof(ares));
330 }
331 
332 static void
333 ldapd_log_verbose(struct imsg *imsg)
334 {
335 	int	 verbose;
336 
337 	if (imsg->hdr.len != sizeof(verbose) + IMSG_HEADER_SIZE)
338 		fatal("invalid size of log verbose request");
339 
340 	bcopy(imsg->data, &verbose, sizeof(verbose));
341 	log_verbose(verbose);
342 }
343 
344 static void
345 ldapd_open_request(struct imsgev *iev, struct imsg *imsg)
346 {
347 	struct open_req		*oreq = imsg->data;
348 	int			 oflags, fd;
349 
350 	if (imsg->hdr.len != sizeof(*oreq) + IMSG_HEADER_SIZE)
351 		fatal("invalid size of open request");
352 
353 	/* make sure path is null-terminated */
354 	oreq->path[MAXPATHLEN] = '\0';
355 
356 	if (strncmp(oreq->path, DATADIR, strlen(DATADIR)) != 0) {
357 		log_warnx("refusing to open file %s", oreq->path);
358 		fatal("ldape sent invalid open request");
359 	}
360 
361 	if (oreq->rdonly)
362 		oflags = O_RDONLY;
363 	else
364 		oflags = O_RDWR | O_CREAT | O_APPEND;
365 
366 	log_debug("opening [%s]", oreq->path);
367 	fd = open(oreq->path, oflags | O_NOFOLLOW, 0600);
368 	if (fd == -1)
369 		log_warn("%s", oreq->path);
370 
371 	imsgev_compose(iev, IMSG_LDAPD_OPEN_RESULT, 0, 0, fd, oreq,
372 	    sizeof(*oreq));
373 }
374 
375