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 #include <sys/param.h>
58 #include <sys/time.h>
59 #include <ctype.h>
60 #include <err.h>
61 #include <errno.h>
62 #include <fcntl.h>
63 #include <signal.h>
64 #include <stdio.h>
65 #include <stdlib.h>
66 #include <string.h>
67 #include <syslog.h>
68 #include <unistd.h>
69 #include "defs.h"
70
71 static void usage(void) __dead2;
72
73 int
main(int argc,char * argv[])74 main(int argc, char *argv[])
75 {
76 int c, fd, omask, maxfds;
77 fd_set rset;
78
79 /*
80 * Close any open file descriptors.
81 * Temporarily leave stdin & stdout open for `-d',
82 * and stderr open for any pre-syslog error messages.
83 */
84 {
85 int i, nfds = getdtablesize();
86
87 for (i = 0; i < nfds; i++)
88 if (i != fileno(stdin) && i != fileno(stdout) &&
89 i != fileno(stderr))
90 (void) close(i);
91 }
92
93 /*
94 * Parse any arguments.
95 */
96 while ((c = getopt(argc, argv, "adi:")) != -1)
97 switch(c) {
98 case 'a':
99 BootAny++;
100 break;
101 case 'd':
102 DebugFlg++;
103 break;
104 case 'i':
105 IntfName = optarg;
106 break;
107 default:
108 usage();
109 }
110 for (; optind < argc; optind++) {
111 if (ConfigFile == NULL)
112 ConfigFile = argv[optind];
113 else {
114 warnx("too many config files (`%s' ignored)",
115 argv[optind]);
116 }
117 }
118
119 if (ConfigFile == NULL) /* use default config file */
120 ConfigFile = DfltConfig;
121
122 if (DebugFlg) {
123 DbgFp = stdout; /* output to stdout */
124
125 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */
126 (void) signal(SIGUSR2, SIG_IGN);
127 (void) fclose(stderr); /* finished with it */
128 } else {
129 if (daemon(0, 0))
130 err(1, "can't detach from terminal");
131
132 (void) signal(SIGUSR1, DebugOn);
133 (void) signal(SIGUSR2, DebugOff);
134 }
135
136 openlog("rbootd", LOG_PID, LOG_DAEMON);
137
138 /*
139 * If no interface was specified, get one now.
140 *
141 * This is convoluted because we want to get the default interface
142 * name for the syslog("restarted") message. If BpfGetIntfName()
143 * runs into an error, it will return a syslog-able error message
144 * (in `errmsg') which will be displayed here.
145 */
146 if (IntfName == NULL) {
147 char *errmsg;
148
149 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) {
150 /* Backslash to avoid trigraph '??)'. */
151 syslog(LOG_NOTICE, "restarted (?\?)");
152 /* BpfGetIntfName() returns safe names, using %m */
153 syslog(LOG_ERR, "%s", errmsg);
154 Exit(0);
155 }
156 }
157
158 syslog(LOG_NOTICE, "restarted (%s)", IntfName);
159
160 (void) signal(SIGHUP, ReConfig);
161 (void) signal(SIGINT, Exit);
162 (void) signal(SIGTERM, Exit);
163
164 /*
165 * Grab our host name and pid.
166 */
167 if (gethostname(MyHost, MAXHOSTNAMELEN - 1) < 0) {
168 syslog(LOG_ERR, "gethostname: %m");
169 Exit(0);
170 }
171 MyHost[MAXHOSTNAMELEN - 1] = '\0';
172
173 MyPid = getpid();
174
175 /*
176 * Write proc's pid to a file.
177 */
178 {
179 FILE *fp;
180
181 if ((fp = fopen(PidFile, "w")) != NULL) {
182 (void) fprintf(fp, "%d\n", (int) MyPid);
183 (void) fclose(fp);
184 } else {
185 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile);
186 }
187 }
188
189 /*
190 * All boot files are relative to the boot directory, we might
191 * as well chdir() there to make life easier.
192 */
193 if (chdir(BootDir) < 0) {
194 syslog(LOG_ERR, "chdir: %m (%s)", BootDir);
195 Exit(0);
196 }
197
198 /*
199 * Initial configuration.
200 */
201 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */
202 if (GetBootFiles() == 0) /* get list of boot files */
203 Exit(0);
204 if (ParseConfig() == 0) /* parse config file */
205 Exit(0);
206
207 /*
208 * Open and initialize a BPF device for the appropriate interface.
209 * If an error is encountered, a message is displayed and Exit()
210 * is called.
211 */
212 fd = BpfOpen();
213
214 (void) sigsetmask(omask); /* allow reconfig's */
215
216 /*
217 * Main loop: receive a packet, determine where it came from,
218 * and if we service this host, call routine to handle request.
219 */
220 maxfds = fd + 1;
221 FD_ZERO(&rset);
222 FD_SET(fd, &rset);
223 for (;;) {
224 struct timeval timeout;
225 fd_set r;
226 int nsel;
227
228 r = rset;
229
230 if (RmpConns == NULL) { /* timeout isn't necessary */
231 nsel = select(maxfds, &r, NULL, NULL, NULL);
232 } else {
233 timeout.tv_sec = RMP_TIMEOUT;
234 timeout.tv_usec = 0;
235 nsel = select(maxfds, &r, NULL, NULL, &timeout);
236 }
237
238 if (nsel < 0) {
239 if (errno == EINTR)
240 continue;
241 syslog(LOG_ERR, "select: %m");
242 Exit(0);
243 } else if (nsel == 0) { /* timeout */
244 DoTimeout(); /* clear stale conns */
245 continue;
246 }
247
248 if (FD_ISSET(fd, &r)) {
249 RMPCONN rconn;
250 CLIENT *client;
251 int doread = 1;
252
253 while (BpfRead(&rconn, doread)) {
254 doread = 0;
255
256 if (DbgFp != NULL) /* display packet */
257 DispPkt(&rconn,DIR_RCVD);
258
259 omask = sigblock(sigmask(SIGHUP));
260
261 /*
262 * If we do not restrict service, set the
263 * client to NULL (ProcessPacket() handles
264 * this). Otherwise, check that we can
265 * service this host; if not, log a message
266 * and ignore the packet.
267 */
268 if (BootAny) {
269 client = NULL;
270 } else if ((client=FindClient(&rconn))==NULL) {
271 syslog(LOG_INFO,
272 "%s: boot packet ignored",
273 EnetStr(&rconn));
274 (void) sigsetmask(omask);
275 continue;
276 }
277
278 ProcessPacket(&rconn,client);
279
280 (void) sigsetmask(omask);
281 }
282 }
283 }
284 }
285
286 static void
usage(void)287 usage(void)
288 {
289 fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n");
290 exit (1);
291 }
292
293 /*
294 ** DoTimeout -- Free any connections that have timed out.
295 **
296 ** Parameters:
297 ** None.
298 **
299 ** Returns:
300 ** Nothing.
301 **
302 ** Side Effects:
303 ** - Timed out connections in `RmpConns' will be freed.
304 */
305 void
DoTimeout(void)306 DoTimeout(void)
307 {
308 RMPCONN *rtmp;
309 time_t now;
310
311 /*
312 * For each active connection, if RMP_TIMEOUT seconds have passed
313 * since the last packet was sent, delete the connection.
314 */
315 now = time(NULL);
316 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next)
317 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now) {
318 syslog(LOG_WARNING, "%s: connection timed out (%u)",
319 EnetStr(rtmp), rtmp->rmp.r_type);
320 RemoveConn(rtmp);
321 }
322 }
323
324 /*
325 ** FindClient -- Find client associated with a packet.
326 **
327 ** Parameters:
328 ** rconn - the new packet.
329 **
330 ** Returns:
331 ** Pointer to client info if found, NULL otherwise.
332 **
333 ** Side Effects:
334 ** None.
335 **
336 ** Warnings:
337 ** - This routine must be called with SIGHUP blocked since
338 ** a reconfigure can invalidate the information returned.
339 */
340
341 CLIENT *
FindClient(RMPCONN * rconn)342 FindClient(RMPCONN *rconn)
343 {
344 CLIENT *ctmp;
345
346 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next)
347 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0],
348 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0)
349 break;
350
351 return(ctmp);
352 }
353
354 /*
355 ** Exit -- Log an error message and exit.
356 **
357 ** Parameters:
358 ** sig - caught signal (or zero if not dying on a signal).
359 **
360 ** Returns:
361 ** Does not return.
362 **
363 ** Side Effects:
364 ** - This process ceases to exist.
365 */
366 void
Exit(int sig)367 Exit(int sig)
368 {
369 if (sig > 0)
370 syslog(LOG_ERR, "going down on signal %d", sig);
371 else
372 syslog(LOG_ERR, "going down with fatal error");
373 BpfClose();
374 exit(1);
375 }
376
377 /*
378 ** ReConfig -- Get new list of boot files and reread config files.
379 **
380 ** Parameters:
381 ** None.
382 **
383 ** Returns:
384 ** Nothing.
385 **
386 ** Side Effects:
387 ** - All active connections are dropped.
388 ** - List of boot-able files is changed.
389 ** - List of clients is changed.
390 **
391 ** Warnings:
392 ** - This routine must be called with SIGHUP blocked.
393 */
394 void
ReConfig(int signo __unused)395 ReConfig(int signo __unused)
396 {
397 syslog(LOG_NOTICE, "reconfiguring boot server");
398
399 FreeConns();
400
401 if (GetBootFiles() == 0)
402 Exit(0);
403
404 if (ParseConfig() == 0)
405 Exit(0);
406 }
407
408 /*
409 ** DebugOff -- Turn off debugging.
410 **
411 ** Parameters:
412 ** None.
413 **
414 ** Returns:
415 ** Nothing.
416 **
417 ** Side Effects:
418 ** - Debug file is closed.
419 */
420 void
DebugOff(int signo __unused)421 DebugOff(int signo __unused)
422 {
423 if (DbgFp != NULL)
424 (void) fclose(DbgFp);
425
426 DbgFp = NULL;
427 }
428
429 /*
430 ** DebugOn -- Turn on debugging.
431 **
432 ** Parameters:
433 ** None.
434 **
435 ** Returns:
436 ** Nothing.
437 **
438 ** Side Effects:
439 ** - Debug file is opened/truncated if not already opened,
440 ** otherwise do nothing.
441 */
442 void
DebugOn(int signo __unused)443 DebugOn(int signo __unused)
444 {
445 if (DbgFp == NULL) {
446 if ((DbgFp = fopen(DbgFile, "w")) == NULL)
447 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile);
448 }
449 }
450