1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1988, 1992 The University of Utah and the Center
5 * for Software Science (CSS).
6 * Copyright (c) 1992, 1993
7 * The Regents of the University of California. All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * the Center for Software Science of the University of Utah Computer
11 * Science Department. CSS requests users of this software to return
12 * to [email protected] any improvements that they make and grant
13 * CSS redistribution rights.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * from: @(#)rbootd.c 8.1 (Berkeley) 6/4/93
40 *
41 * From: Utah Hdr: rbootd.c 3.1 92/07/06
42 * Author: Jeff Forys, University of Utah CSS
43 */
44
45 #ifndef lint
46 static const char copyright[] =
47 "@(#) Copyright (c) 1992, 1993\n\
48 The Regents of the University of California. All rights reserved.\n";
49 #endif /* not lint */
50
51 #ifndef lint
52 #if 0
53 static const char sccsid[] = "@(#)rbootd.c 8.1 (Berkeley) 6/4/93";
54 #endif
55 #endif /* not lint */
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
58
59 #include <sys/param.h>
60 #include <sys/time.h>
61 #include <ctype.h>
62 #include <err.h>
63 #include <errno.h>
64 #include <fcntl.h>
65 #include <signal.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <syslog.h>
70 #include <unistd.h>
71 #include "defs.h"
72
73 static void usage(void);
74
75 int
main(int argc,char * argv[])76 main(int argc, char *argv[])
77 {
78 int c, fd, omask, maxfds;
79 fd_set rset;
80
81 /*
82 * Close any open file descriptors.
83 * Temporarily leave stdin & stdout open for `-d',
84 * and stderr open for any pre-syslog error messages.
85 */
86 {
87 int i, nfds = getdtablesize();
88
89 for (i = 0; i < nfds; i++)
90 if (i != fileno(stdin) && i != fileno(stdout) &&
91 i != fileno(stderr))
92 (void) close(i);
93 }
94
95 /*
96 * Parse any arguments.
97 */
98 while ((c = getopt(argc, argv, "adi:")) != -1)
99 switch(c) {
100 case 'a':
101 BootAny++;
102 break;
103 case 'd':
104 DebugFlg++;
105 break;
106 case 'i':
107 IntfName = optarg;
108 break;
109 default:
110 usage();
111 }
112 for (; optind < argc; optind++) {
113 if (ConfigFile == NULL)
114 ConfigFile = argv[optind];
115 else {
116 warnx("too many config files (`%s' ignored)",
117 argv[optind]);
118 }
119 }
120
121 if (ConfigFile == NULL) /* use default config file */
122 ConfigFile = DfltConfig;
123
124 if (DebugFlg) {
125 DbgFp = stdout; /* output to stdout */
126
127 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */
128 (void) signal(SIGUSR2, SIG_IGN);
129 (void) fclose(stderr); /* finished with it */
130 } else {
131 if (daemon(0, 0))
132 err(1, "can't detach from terminal");
133
134 (void) signal(SIGUSR1, DebugOn);
135 (void) signal(SIGUSR2, DebugOff);
136 }
137
138 openlog("rbootd", LOG_PID, LOG_DAEMON);
139
140 /*
141 * If no interface was specified, get one now.
142 *
143 * This is convoluted because we want to get the default interface
144 * name for the syslog("restarted") message. If BpfGetIntfName()
145 * runs into an error, it will return a syslog-able error message
146 * (in `errmsg') which will be displayed here.
147 */
148 if (IntfName == NULL) {
149 char *errmsg;
150
151 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) {
152 /* Backslash to avoid trigraph '??)'. */
153 syslog(LOG_NOTICE, "restarted (?\?)");
154 /* BpfGetIntfName() returns safe names, using %m */
155 syslog(LOG_ERR, "%s", errmsg);
156 Exit(0);
157 }
158 }
159
160 syslog(LOG_NOTICE, "restarted (%s)", IntfName);
161
162 (void) signal(SIGHUP, ReConfig);
163 (void) signal(SIGINT, Exit);
164 (void) signal(SIGTERM, Exit);
165
166 /*
167 * Grab our host name and pid.
168 */
169 if (gethostname(MyHost, MAXHOSTNAMELEN - 1) < 0) {
170 syslog(LOG_ERR, "gethostname: %m");
171 Exit(0);
172 }
173 MyHost[MAXHOSTNAMELEN - 1] = '\0';
174
175 MyPid = getpid();
176
177 /*
178 * Write proc's pid to a file.
179 */
180 {
181 FILE *fp;
182
183 if ((fp = fopen(PidFile, "w")) != NULL) {
184 (void) fprintf(fp, "%d\n", (int) MyPid);
185 (void) fclose(fp);
186 } else {
187 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile);
188 }
189 }
190
191 /*
192 * All boot files are relative to the boot directory, we might
193 * as well chdir() there to make life easier.
194 */
195 if (chdir(BootDir) < 0) {
196 syslog(LOG_ERR, "chdir: %m (%s)", BootDir);
197 Exit(0);
198 }
199
200 /*
201 * Initial configuration.
202 */
203 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */
204 if (GetBootFiles() == 0) /* get list of boot files */
205 Exit(0);
206 if (ParseConfig() == 0) /* parse config file */
207 Exit(0);
208
209 /*
210 * Open and initialize a BPF device for the appropriate interface.
211 * If an error is encountered, a message is displayed and Exit()
212 * is called.
213 */
214 fd = BpfOpen();
215
216 (void) sigsetmask(omask); /* allow reconfig's */
217
218 /*
219 * Main loop: receive a packet, determine where it came from,
220 * and if we service this host, call routine to handle request.
221 */
222 maxfds = fd + 1;
223 FD_ZERO(&rset);
224 FD_SET(fd, &rset);
225 for (;;) {
226 struct timeval timeout;
227 fd_set r;
228 int nsel;
229
230 r = rset;
231
232 if (RmpConns == NULL) { /* timeout isn't necessary */
233 nsel = select(maxfds, &r, NULL, NULL, NULL);
234 } else {
235 timeout.tv_sec = RMP_TIMEOUT;
236 timeout.tv_usec = 0;
237 nsel = select(maxfds, &r, NULL, NULL, &timeout);
238 }
239
240 if (nsel < 0) {
241 if (errno == EINTR)
242 continue;
243 syslog(LOG_ERR, "select: %m");
244 Exit(0);
245 } else if (nsel == 0) { /* timeout */
246 DoTimeout(); /* clear stale conns */
247 continue;
248 }
249
250 if (FD_ISSET(fd, &r)) {
251 RMPCONN rconn;
252 CLIENT *client, *FindClient();
253 int doread = 1;
254
255 while (BpfRead(&rconn, doread)) {
256 doread = 0;
257
258 if (DbgFp != NULL) /* display packet */
259 DispPkt(&rconn,DIR_RCVD);
260
261 omask = sigblock(sigmask(SIGHUP));
262
263 /*
264 * If we do not restrict service, set the
265 * client to NULL (ProcessPacket() handles
266 * this). Otherwise, check that we can
267 * service this host; if not, log a message
268 * and ignore the packet.
269 */
270 if (BootAny) {
271 client = NULL;
272 } else if ((client=FindClient(&rconn))==NULL) {
273 syslog(LOG_INFO,
274 "%s: boot packet ignored",
275 EnetStr(&rconn));
276 (void) sigsetmask(omask);
277 continue;
278 }
279
280 ProcessPacket(&rconn,client);
281
282 (void) sigsetmask(omask);
283 }
284 }
285 }
286 }
287
288 static void
usage(void)289 usage(void)
290 {
291 fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n");
292 exit (1);
293 }
294
295 /*
296 ** DoTimeout -- Free any connections that have timed out.
297 **
298 ** Parameters:
299 ** None.
300 **
301 ** Returns:
302 ** Nothing.
303 **
304 ** Side Effects:
305 ** - Timed out connections in `RmpConns' will be freed.
306 */
307 void
DoTimeout(void)308 DoTimeout(void)
309 {
310 RMPCONN *rtmp;
311 time_t now;
312
313 /*
314 * For each active connection, if RMP_TIMEOUT seconds have passed
315 * since the last packet was sent, delete the connection.
316 */
317 now = time(NULL);
318 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next)
319 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now) {
320 syslog(LOG_WARNING, "%s: connection timed out (%u)",
321 EnetStr(rtmp), rtmp->rmp.r_type);
322 RemoveConn(rtmp);
323 }
324 }
325
326 /*
327 ** FindClient -- Find client associated with a packet.
328 **
329 ** Parameters:
330 ** rconn - the new packet.
331 **
332 ** Returns:
333 ** Pointer to client info if found, NULL otherwise.
334 **
335 ** Side Effects:
336 ** None.
337 **
338 ** Warnings:
339 ** - This routine must be called with SIGHUP blocked since
340 ** a reconfigure can invalidate the information returned.
341 */
342
343 CLIENT *
FindClient(RMPCONN * rconn)344 FindClient(RMPCONN *rconn)
345 {
346 CLIENT *ctmp;
347
348 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next)
349 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0],
350 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0)
351 break;
352
353 return(ctmp);
354 }
355
356 /*
357 ** Exit -- Log an error message and exit.
358 **
359 ** Parameters:
360 ** sig - caught signal (or zero if not dying on a signal).
361 **
362 ** Returns:
363 ** Does not return.
364 **
365 ** Side Effects:
366 ** - This process ceases to exist.
367 */
368 void
Exit(int sig)369 Exit(int sig)
370 {
371 if (sig > 0)
372 syslog(LOG_ERR, "going down on signal %d", sig);
373 else
374 syslog(LOG_ERR, "going down with fatal error");
375 BpfClose();
376 exit(1);
377 }
378
379 /*
380 ** ReConfig -- Get new list of boot files and reread config files.
381 **
382 ** Parameters:
383 ** None.
384 **
385 ** Returns:
386 ** Nothing.
387 **
388 ** Side Effects:
389 ** - All active connections are dropped.
390 ** - List of boot-able files is changed.
391 ** - List of clients is changed.
392 **
393 ** Warnings:
394 ** - This routine must be called with SIGHUP blocked.
395 */
396 void
ReConfig(int signo __unused)397 ReConfig(int signo __unused)
398 {
399 syslog(LOG_NOTICE, "reconfiguring boot server");
400
401 FreeConns();
402
403 if (GetBootFiles() == 0)
404 Exit(0);
405
406 if (ParseConfig() == 0)
407 Exit(0);
408 }
409
410 /*
411 ** DebugOff -- Turn off debugging.
412 **
413 ** Parameters:
414 ** None.
415 **
416 ** Returns:
417 ** Nothing.
418 **
419 ** Side Effects:
420 ** - Debug file is closed.
421 */
422 void
DebugOff(int signo __unused)423 DebugOff(int signo __unused)
424 {
425 if (DbgFp != NULL)
426 (void) fclose(DbgFp);
427
428 DbgFp = NULL;
429 }
430
431 /*
432 ** DebugOn -- Turn on debugging.
433 **
434 ** Parameters:
435 ** None.
436 **
437 ** Returns:
438 ** Nothing.
439 **
440 ** Side Effects:
441 ** - Debug file is opened/truncated if not already opened,
442 ** otherwise do nothing.
443 */
444 void
DebugOn(int signo __unused)445 DebugOn(int signo __unused)
446 {
447 if (DbgFp == NULL) {
448 if ((DbgFp = fopen(DbgFile, "w")) == NULL)
449 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile);
450 }
451 }
452