2 * Copyright (c) 1985, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 static char sccsid[] = "@(#)readmsg.c 8.1 (Berkeley) 6/6/93";
38 static const char rcsid[] =
44 extern char *tsptype[];
47 * LOOKAT checks if the message is of the requested type and comes from
48 * the right machine, returning 1 in case of affirmative answer
50 #define LOOKAT(msg, mtype, mfrom, netp, froms) \
51 (((mtype) == TSP_ANY || (mtype) == (msg).tsp_type) && \
52 ((mfrom) == 0 || !strcmp((mfrom), (msg).tsp_name)) && \
54 ((netp)->mask & (froms).sin_addr.s_addr) == (netp)->net.s_addr))
56 struct timeval rtime, rwait, rtout;
58 static struct tsplist {
61 struct sockaddr_in addr;
64 struct sockaddr_in from;
65 struct netinfo *fromnet;
66 struct timeval from_when;
69 * `readmsg' returns message `type' sent by `machfrom' if it finds it
70 * either in the receive queue, or in a linked list of previously received
71 * messages that it maintains.
72 * Otherwise it waits to see if the appropriate message arrives within
73 * `intvl' seconds. If not, it returns NULL.
77 readmsg(type, machfrom, intvl, netfrom)
80 struct timeval *intvl;
81 struct netinfo *netfrom;
85 static struct tsplist *head = &msgslist;
86 static struct tsplist *tail = &msgslist;
87 static int msgcnt = 0;
89 register struct netinfo *ntp;
90 register struct tsplist *ptr;
94 fprintf(fd, "readmsg: looking for %s from %s, %s\n",
95 tsptype[type], machfrom == NULL ? "ANY" : machfrom,
96 netfrom == NULL ? "ANYNET" : inet_ntoa(netfrom->net));
99 for (ptr = head->p; ptr != 0; ptr = ptr->p) {
100 /* do not repeat the hundreds of messages */
103 fprintf(fd,"\t ...%d skipped\n",
109 fprintf(fd, length > 1 ? "\t" : "queue:\t");
110 print(&ptr->info, &ptr->addr);
119 * Look for the requested message scanning through the
120 * linked list. If found, return it and free the space
123 while (ptr != NULL) {
124 if (LOOKAT(ptr->info, type, machfrom, netfrom, ptr->addr)) {
128 from_when = ptr->when;
135 for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
136 if ((ntp->mask & from.sin_addr.s_addr) ==
145 fprintf(fd, "readmsg: found ");
146 print(&msgin, &from);
149 /* The protocol can get far behind. When it does, it gets
150 * hopelessly confused. So delete duplicate messages.
152 for (ptr = prev; (ptr = ptr->p) != NULL; prev = ptr) {
153 if (ptr->addr.sin_addr.s_addr
154 == from.sin_addr.s_addr
155 && ptr->info.tsp_type == msgin.tsp_type) {
157 fprintf(fd, "\tdup ");
170 * If the message was not in the linked list, it may still be
171 * coming from the network. Set the timer and wait
172 * on a select to read the next incoming message: if it is the
173 * right one, return it, otherwise insert it in the linked list.
176 (void)gettimeofday(&rtout, 0);
177 timevaladd(&rtout, intvl);
180 (void)gettimeofday(&rtime, 0);
181 timevalsub(&rwait, &rtout, &rtime);
182 if (rwait.tv_sec < 0)
183 rwait.tv_sec = rwait.tv_usec = 0;
184 else if (rwait.tv_sec == 0
185 && rwait.tv_usec < 1000000/CLK_TCK)
186 rwait.tv_usec = 1000000/CLK_TCK;
189 fprintf(fd, "readmsg: wait %ld.%6ld at %s\n",
190 rwait.tv_sec, rwait.tv_usec, date());
191 /* Notice a full disk, as we flush trace info.
192 * It is better to flush periodically than at
193 * every line because the tracing consists of bursts
194 * of many lines. Without care, tracing slows
195 * down the code enough to break the protocol.
197 if (rwait.tv_sec != 0
198 && EOF == fflush(fd))
199 traceoff("Tracing ended for cause at %s\n");
202 FD_SET(sock, &ready);
203 if (!select(sock+1, &ready, (fd_set *)0, (fd_set *)0,
205 if (rwait.tv_sec == 0 && rwait.tv_usec == 0)
209 length = sizeof(from);
210 if ((n = recvfrom(sock, (char *)&msgin, sizeof(struct tsp), 0,
211 (struct sockaddr*)&from, &length)) < 0) {
212 syslog(LOG_ERR, "recvfrom: %m");
216 * The 4.3BSD protocol spec had a 32-byte tsp_name field, and
217 * this is still OS-dependent. Demand that the packet is at
218 * least long enough to hold a 4.3BSD packet.
220 if (n < (ssize_t)(sizeof(struct tsp) - MAXHOSTNAMELEN + 32)) {
222 "short packet (%u/%u bytes) from %s",
223 n, sizeof(struct tsp) - MAXHOSTNAMELEN + 32,
224 inet_ntoa(from.sin_addr));
227 (void)gettimeofday(&from_when, (struct timezone *)0);
228 bytehostorder(&msgin);
230 if (msgin.tsp_vers > TSPVERSION) {
232 fprintf(fd,"readmsg: version mismatch\n");
233 /* should do a dump of the packet */
238 if (memchr(msgin.tsp_name,
239 '\0', sizeof msgin.tsp_name) == NULL) {
240 syslog(LOG_NOTICE, "hostname field not NUL terminated "
241 "in packet from %s", inet_ntoa(from.sin_addr));
246 for (ntp = nettab; ntp != NULL; ntp = ntp->next)
247 if ((ntp->mask & from.sin_addr.s_addr) ==
254 * drop packets from nets we are ignoring permanently
256 if (fromnet == NULL) {
258 * The following messages may originate on
259 * this host with an ignored network address
261 if (msgin.tsp_type != TSP_TRACEON &&
262 msgin.tsp_type != TSP_SETDATE &&
263 msgin.tsp_type != TSP_MSITE &&
264 msgin.tsp_type != TSP_TEST &&
265 msgin.tsp_type != TSP_TRACEOFF) {
267 fprintf(fd,"readmsg: discard null net ");
268 print(&msgin, &from);
275 * Throw away messages coming from this machine,
276 * unless they are of some particular type.
277 * This gets rid of broadcast messages and reduces
278 * master processing time.
280 if (!strcmp(msgin.tsp_name, hostname)
281 && msgin.tsp_type != TSP_SETDATE
282 && msgin.tsp_type != TSP_TEST
283 && msgin.tsp_type != TSP_MSITE
284 && msgin.tsp_type != TSP_TRACEON
285 && msgin.tsp_type != TSP_TRACEOFF
286 && msgin.tsp_type != TSP_LOOP) {
288 fprintf(fd, "readmsg: discard own ");
289 print(&msgin, &from);
295 * Send acknowledgements here; this is faster and
296 * avoids deadlocks that would occur if acks were
297 * sent from a higher level routine. Different
298 * acknowledgements are necessary, depending on
301 if (fromnet == NULL) /* do not de-reference 0 */
303 else if (fromnet->status == MASTER)
305 else if (fromnet->status == SLAVE)
310 if (LOOKAT(msgin, type, machfrom, netfrom, from)) {
312 fprintf(fd, "readmsg: ");
313 print(&msgin, &from);
316 } else if (++msgcnt > NHOSTS*3) {
318 /* The protocol gets hopelessly confused if it gets too far
319 * behind. However, it seems able to recover from all cases of lost
320 * packets. Therefore, if we are swamped, throw everything away.
324 "readmsg: discarding %d msgs\n",
327 while ((ptr=head->p) != NULL) {
333 tail->p = (struct tsplist *)
334 malloc(sizeof(struct tsplist));
339 /* timestamp msgs so SETTIMEs are correct */
340 tail->when = from_when;
346 * Send the necessary acknowledgements:
347 * only the type ACK is to be sent by a slave
352 switch(msgin.tsp_type) {
362 fprintf(fd, "Slaveack: ");
363 print(&msgin, &from);
365 xmit(TSP_ACK,msgin.tsp_seq, &from);
370 fprintf(fd, "Slaveack: no ack: ");
371 print(&msgin, &from);
378 * Certain packets may arrive from this machine on ignored networks.
379 * These packets should be acknowledged.
384 switch(msgin.tsp_type) {
390 fprintf(fd, "Ignoreack: ");
391 print(&msgin, &from);
393 xmit(TSP_ACK,msgin.tsp_seq, &from);
398 fprintf(fd, "Ignoreack: no ack: ");
399 print(&msgin, &from);
406 * `masterack' sends the necessary acknowledgments
407 * to the messages received by a master
415 resp.tsp_vers = TSPVERSION;
416 (void)strcpy(resp.tsp_name, hostname);
418 switch(msgin.tsp_type) {
425 fprintf(fd, "Masterack: ");
426 print(&msgin, &from);
428 xmit(TSP_ACK,msgin.tsp_seq, &from);
434 fprintf(fd, "Masterack: ");
435 print(&msgin, &from);
437 xmit(TSP_MASTERACK,msgin.tsp_seq, &from);
442 fprintf(fd,"Masterack: no ack: ");
443 print(&msgin, &from);
450 * Print a TSP message
455 struct sockaddr_in *addr;
460 if (msg->tsp_type >= TSPTYPENUMBER) {
461 fprintf(fd, "bad type (%u) on packet from %s\n",
462 msg->tsp_type, inet_ntoa(addr->sin_addr));
466 switch (msg->tsp_type) {
469 fprintf(fd, "%s %d %-6u #%d %-15s %s\n",
470 tsptype[msg->tsp_type],
474 inet_ntoa(addr->sin_addr),
481 tsp_time_sec = msg->tsp_time.tv_sec;
482 strncpy(tm, ctime(&tsp_time_sec)+3+1, sizeof(tm));
483 tm[15] = '\0'; /* ugh */
484 fprintf(fd, "%s %d %-6u %s %-15s %s\n",
485 tsptype[msg->tsp_type],
489 inet_ntoa(addr->sin_addr),
494 fprintf(fd, "%s %d %-6u (%ld,%ld) %-15s %s\n",
495 tsptype[msg->tsp_type],
498 msg->tsp_time.tv_sec,
499 msg->tsp_time.tv_usec,
500 inet_ntoa(addr->sin_addr),
505 fprintf(fd, "%s %d %-6u %-15s %s\n",
506 tsptype[msg->tsp_type],
509 inet_ntoa(addr->sin_addr),