2 * Copyright (c) 1983, 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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 static const char copyright[] =
32 "@(#) Copyright (c) 1983, 1993\n\
33 The Regents of the University of California. All rights reserved.\n";
38 static char sccsid[] = "@(#)rwhod.c 8.1 (Berkeley) 6/6/93";
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
45 #include <sys/param.h>
46 #include <sys/socket.h>
48 #include <sys/signal.h>
49 #include <sys/ioctl.h>
50 #include <sys/sysctl.h>
53 #include <net/if_dl.h>
54 #include <net/route.h>
55 #include <netinet/in.h>
56 #include <arpa/inet.h>
57 #include <protocols/rwhod.h>
76 * This version of Berkeley's rwhod has been modified to use IP multicast
77 * datagrams, under control of a new command-line option:
79 * rwhod -m causes rwhod to use IP multicast (instead of
80 * broadcast or unicast) on all interfaces that have
81 * the IFF_MULTICAST flag set in their "ifnet" structs
82 * (excluding the loopback interface). The multicast
83 * reports are sent with a time-to-live of 1, to prevent
84 * forwarding beyond the directly-connected subnet(s).
86 * rwhod -m <ttl> causes rwhod to send IP multicast datagrams with a
87 * time-to-live of <ttl>, via a SINGLE interface rather
88 * than all interfaces. <ttl> must be between 0 and
89 * MAX_MULTICAST_SCOPE, defined below. Note that "-m 1"
90 * is different than "-m", in that "-m 1" specifies
91 * transmission on one interface only.
93 * When "-m" is used without a <ttl> argument, the program accepts multicast
94 * rwhod reports from all multicast-capable interfaces. If a <ttl> argument
95 * is given, it accepts multicast reports from only one interface, the one
96 * on which reports are sent (which may be controlled via the host's routing
97 * table). Regardless of the "-m" option, the program accepts broadcast or
98 * unicast reports from all interfaces. Thus, this program will hear the
99 * reports of old, non-multicasting rwhods, but, if multicasting is used,
100 * those old rwhods won't hear the reports generated by this program.
102 * -- Steve Deering, Stanford University, February 1989
105 #define UNPRIV_USER "daemon"
106 #define UNPRIV_GROUP "daemon"
108 #define NO_MULTICAST 0 /* multicast modes */
109 #define PER_INTERFACE_MULTICAST 1
110 #define SCOPED_MULTICAST 2
112 #define MAX_MULTICAST_SCOPE 32 /* "site-wide", by convention */
114 #define INADDR_WHOD_GROUP (u_long)0xe0000103 /* 224.0.1.3 */
115 /* (belongs in protocols/rwhod.h) */
119 int iff_flag = IFF_POINTOPOINT;
120 int multicast_mode = NO_MULTICAST;
122 struct sockaddr_in multicast_addr =
123 { sizeof multicast_addr, AF_INET, 0, { 0 }, { 0 } };
126 * Alarm interval. Don't forget to change the down time check in ruptime
127 * if this is changed.
129 #define AL_INTERVAL (3 * 60)
131 char myname[MAXHOSTNAMELEN];
134 * We communicate with each neighbor in a list constructed at the time we're
135 * started up. Neighbors are currently directly connected via a hardware
139 struct neighbor *n_next;
140 char *n_name; /* interface name */
141 struct sockaddr *n_addr; /* who to send to */
142 int n_addrlen; /* size of address */
143 int n_flags; /* should forward?, interface flags */
146 struct neighbor *neighbors;
151 #define WHDRSIZE (int)(sizeof(mywd) - sizeof(mywd.wd_we))
153 void run_as(uid_t *, gid_t *);
155 void getboottime(int);
157 void quit(const char *);
158 void rt_xaddrs(caddr_t, caddr_t, struct rt_addrinfo *);
159 int verify(char *, int);
160 static void usage(void);
162 char *interval(int, char *);
163 void Sendto(int, const void *, size_t, int, const struct sockaddr *, int);
164 #define sendto Sendto
168 main(int argc, char *argv[])
170 struct sockaddr_in from;
175 struct sockaddr_in soin;
180 errx(1, "not super user");
182 run_as(&unpriv_uid, &unpriv_gid);
185 while (argc > 0 && *argv[0] == '-') {
186 if (strcmp(*argv, "-m") == 0) {
187 if (argc > 1 && isdigit(*(argv + 1)[0])) {
189 multicast_mode = SCOPED_MULTICAST;
190 multicast_scope = atoi(*argv);
191 if (multicast_scope > MAX_MULTICAST_SCOPE)
192 errx(1, "ttl must not exceed %u",
193 MAX_MULTICAST_SCOPE);
195 else multicast_mode = PER_INTERFACE_MULTICAST;
197 else if (strcmp(*argv, "-i") == 0)
199 else if (strcmp(*argv, "-l") == 0)
201 else if (strcmp(*argv, "-p") == 0)
212 (void) signal(SIGHUP, getboottime);
213 openlog("rwhod", LOG_PID, LOG_DAEMON);
214 sp = getservbyname("who", "udp");
216 syslog(LOG_ERR, "who/udp: unknown service");
219 if (chdir(_PATH_RWHODIR) < 0) {
220 syslog(LOG_ERR, "%s: %m", _PATH_RWHODIR);
224 * Establish host name as returned by system.
226 if (gethostname(myname, sizeof(myname) - 1) < 0) {
227 syslog(LOG_ERR, "gethostname: %m");
230 if ((cp = index(myname, '.')) != NULL)
232 strncpy(mywd.wd_hostname, myname, sizeof(mywd.wd_hostname) - 1);
233 mywd.wd_hostname[sizeof(mywd.wd_hostname) - 1] = '\0';
234 utmpf = open(_PATH_UTMP, O_RDONLY|O_CREAT, 0644);
236 syslog(LOG_ERR, "%s: %m", _PATH_UTMP);
240 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
241 syslog(LOG_ERR, "socket: %m");
244 if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0) {
245 syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
248 memset(&soin, 0, sizeof(soin));
249 soin.sin_len = sizeof(soin);
250 soin.sin_family = AF_INET;
251 soin.sin_port = sp->s_port;
252 if (bind(s, (struct sockaddr *)&soin, sizeof(soin)) < 0) {
253 syslog(LOG_ERR, "bind: %m");
257 setgroups(1, &unpriv_gid); /* XXX BOGUS groups[0] = egid */
262 signal(SIGALRM, onalrm);
267 socklen_t len = sizeof(from);
271 cc = recvfrom(s, (char *)&wd, sizeof(struct whod), 0,
272 (struct sockaddr *)&from, &len);
274 if (cc < 0 && errno != EINTR)
275 syslog(LOG_WARNING, "recv: %m");
278 if (from.sin_port != sp->s_port && !insecure_mode) {
279 syslog(LOG_WARNING, "%d: bad source port from %s",
280 ntohs(from.sin_port), inet_ntoa(from.sin_addr));
284 syslog(LOG_WARNING, "short packet from %s",
285 inet_ntoa(from.sin_addr));
288 if (wd.wd_vers != WHODVERSION)
290 if (wd.wd_type != WHODTYPE_STATUS)
292 if (!verify(wd.wd_hostname, sizeof wd.wd_hostname)) {
293 syslog(LOG_WARNING, "malformed host name from %s",
294 inet_ntoa(from.sin_addr));
297 (void) snprintf(path, sizeof path, "whod.%s", wd.wd_hostname);
299 * Rather than truncating and growing the file each time,
300 * use ftruncate if size is less than previous size.
302 whod = open(path, O_WRONLY | O_CREAT, 0644);
304 syslog(LOG_WARNING, "%s: %m", path);
307 #if ENDIAN != BIG_ENDIAN
309 int i, n = (cc - WHDRSIZE)/sizeof(struct whoent);
312 /* undo header byte swapping before writing to file */
313 wd.wd_sendtime = ntohl(wd.wd_sendtime);
314 for (i = 0; i < 3; i++)
315 wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]);
316 wd.wd_boottime = ntohl(wd.wd_boottime);
318 for (i = 0; i < n; i++) {
319 we->we_idle = ntohl(we->we_idle);
320 we->we_utmp.out_time =
321 ntohl(we->we_utmp.out_time);
327 wd.wd_recvtime = _time_to_int(t);
328 (void) write(whod, (char *)&wd, cc);
329 if (fstat(whod, &st) < 0 || st.st_size > cc)
338 fprintf(stderr, "usage: rwhod [-i] [-p] [-l] [-m [ttl]]\n");
350 pw = getpwnam(UNPRIV_USER);
352 syslog(LOG_ERR, "getpwnam(%s): %m", UNPRIV_USER);
357 gr = getgrnam(UNPRIV_GROUP);
359 syslog(LOG_ERR, "getgrnam(%s): %m", UNPRIV_GROUP);
366 * Check out host name for unprintables
367 * and other funnies before allowing a file
368 * to be created. Sorry, but blanks aren't allowed.
375 register int size = 0;
377 while (*name && size < maxlen - 1) {
378 if (!isascii(*name) || !(isalnum(*name) || ispunct(*name)))
396 register struct neighbor *np;
397 register struct whoent *we = mywd.wd_we, *wlast;
405 if (alarmcount % 10 == 0)
408 (void) fstat(utmpf, &stb);
409 if ((stb.st_mtime != utmptime) || (stb.st_size > utmpsize)) {
410 utmptime = stb.st_mtime;
411 if (stb.st_size > utmpsize) {
412 utmpsize = stb.st_size + 10 * sizeof(struct utmp);
413 utmp = (struct utmp *)reallocf(utmp, utmpsize);
415 syslog(LOG_WARNING, "malloc failed");
420 (void) lseek(utmpf, (off_t)0, L_SET);
421 cc = read(utmpf, (char *)utmp, stb.st_size);
423 syslog(LOG_ERR, "read(%s): %m", _PATH_UTMP);
426 wlast = &mywd.wd_we[1024 / sizeof(struct whoent) - 1];
427 utmpent = cc / sizeof(struct utmp);
428 for (i = 0; i < utmpent; i++)
429 if (utmp[i].ut_name[0]) {
430 memcpy(we->we_utmp.out_line, utmp[i].ut_line,
431 sizeof(utmp[i].ut_line));
432 memcpy(we->we_utmp.out_name, utmp[i].ut_name,
433 sizeof(utmp[i].ut_name));
434 we->we_utmp.out_time = htonl(utmp[i].ut_time);
439 utmpent = we - mywd.wd_we;
443 * The test on utmpent looks silly---after all, if no one is
444 * logged on, why worry about efficiency?---but is useful on
445 * (e.g.) compute servers.
447 if (utmpent && chdir(_PATH_DEV)) {
448 syslog(LOG_ERR, "chdir(%s): %m", _PATH_DEV);
452 for (i = 0; i < utmpent; i++) {
453 if (stat(we->we_utmp.out_line, &stb) >= 0)
454 we->we_idle = htonl(now - stb.st_atime);
457 (void)getloadavg(avenrun, sizeof(avenrun)/sizeof(avenrun[0]));
458 for (i = 0; i < 3; i++)
459 mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100));
460 cc = (char *)we - (char *)&mywd;
461 mywd.wd_sendtime = htonl(_time_to_time32(time(NULL)));
462 mywd.wd_vers = WHODVERSION;
463 mywd.wd_type = WHODTYPE_STATUS;
464 if (multicast_mode == SCOPED_MULTICAST) {
465 (void) sendto(s, (char *)&mywd, cc, 0,
466 (struct sockaddr *)&multicast_addr,
467 sizeof(multicast_addr));
469 else for (np = neighbors; np != NULL; np = np->n_next) {
470 if (multicast_mode == PER_INTERFACE_MULTICAST &&
471 np->n_flags & IFF_MULTICAST) {
473 * Select the outgoing interface for the multicast.
475 if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
476 &(((struct sockaddr_in *)np->n_addr)->sin_addr),
477 sizeof(struct in_addr)) < 0) {
479 "setsockopt IP_MULTICAST_IF: %m");
482 (void) sendto(s, (char *)&mywd, cc, 0,
483 (struct sockaddr *)&multicast_addr,
484 sizeof(multicast_addr));
485 } else (void) sendto(s, (char *)&mywd, cc, 0,
486 np->n_addr, np->n_addrlen);
488 if (utmpent && chdir(_PATH_RWHODIR)) {
489 syslog(LOG_ERR, "chdir(%s): %m", _PATH_RWHODIR);
493 (void) alarm(AL_INTERVAL);
505 mib[1] = KERN_BOOTTIME;
507 if (sysctl(mib, 2, &tm, &size, NULL, 0) == -1) {
508 syslog(LOG_ERR, "cannot get boottime: %m");
511 mywd.wd_boottime = htonl(_time_to_time32(tm.tv_sec));
518 syslog(LOG_ERR, "%s", msg);
523 rt_xaddrs(cp, cplim, rtinfo)
524 register caddr_t cp, cplim;
525 register struct rt_addrinfo *rtinfo;
527 register struct sockaddr *sa;
530 memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
531 for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
532 if ((rtinfo->rti_addrs & (1 << i)) == 0)
534 rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
540 * Figure out device configuration and select
541 * networks which deserve status information.
547 register struct neighbor *np;
548 register struct if_msghdr *ifm;
549 register struct ifa_msghdr *ifam;
550 struct sockaddr_dl *sdl;
552 int mib[6], flags = 0, len;
553 char *buf, *lim, *next;
554 struct rt_addrinfo info;
556 if (multicast_mode != NO_MULTICAST) {
557 multicast_addr.sin_addr.s_addr = htonl(INADDR_WHOD_GROUP);
558 multicast_addr.sin_port = sp->s_port;
561 if (multicast_mode == SCOPED_MULTICAST) {
565 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
566 mreq.imr_interface.s_addr = htonl(INADDR_ANY);
567 if (setsockopt(so, IPPROTO_IP, IP_ADD_MEMBERSHIP,
568 &mreq, sizeof(mreq)) < 0) {
570 "setsockopt IP_ADD_MEMBERSHIP: %m");
573 ttl = multicast_scope;
574 if (setsockopt(so, IPPROTO_IP, IP_MULTICAST_TTL,
575 &ttl, sizeof(ttl)) < 0) {
577 "setsockopt IP_MULTICAST_TTL: %m");
587 mib[4] = NET_RT_IFLIST;
589 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
590 quit("route-sysctl-estimate");
591 if ((buf = malloc(needed)) == NULL)
593 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
594 quit("actual retrieval of interface table");
597 sdl = NULL; /* XXX just to keep gcc -Wall happy */
598 for (next = buf; next < lim; next += ifm->ifm_msglen) {
599 ifm = (struct if_msghdr *)next;
600 if (ifm->ifm_type == RTM_IFINFO) {
601 sdl = (struct sockaddr_dl *)(ifm + 1);
602 flags = ifm->ifm_flags;
605 if ((flags & IFF_UP) == 0 ||
606 (flags & (((multicast_mode == PER_INTERFACE_MULTICAST) ?
608 IFF_BROADCAST|iff_flag)) == 0)
610 if (ifm->ifm_type != RTM_NEWADDR)
611 quit("out of sync parsing NET_RT_IFLIST");
612 ifam = (struct ifa_msghdr *)ifm;
613 info.rti_addrs = ifam->ifam_addrs;
614 rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam,
616 /* gag, wish we could get rid of Internet dependencies */
617 #define dstaddr info.rti_info[RTAX_BRD]
618 #define ifaddr info.rti_info[RTAX_IFA]
619 #define IPADDR_SA(x) ((struct sockaddr_in *)(x))->sin_addr.s_addr
620 #define PORT_SA(x) ((struct sockaddr_in *)(x))->sin_port
621 if (dstaddr == 0 || dstaddr->sa_family != AF_INET)
623 PORT_SA(dstaddr) = sp->s_port;
624 for (np = neighbors; np != NULL; np = np->n_next)
625 if (memcmp(sdl->sdl_data, np->n_name,
626 sdl->sdl_nlen) == 0 &&
627 IPADDR_SA(np->n_addr) == IPADDR_SA(dstaddr))
631 len = sizeof(*np) + dstaddr->sa_len + sdl->sdl_nlen + 1;
632 np = (struct neighbor *)malloc(len);
634 quit("malloc of neighbor structure");
637 np->n_addr = (struct sockaddr *)(np + 1);
638 np->n_addrlen = dstaddr->sa_len;
639 np->n_name = np->n_addrlen + (char *)np->n_addr;
640 memcpy((char *)np->n_addr, (char *)dstaddr, np->n_addrlen);
641 memcpy(np->n_name, sdl->sdl_data, sdl->sdl_nlen);
642 if (multicast_mode == PER_INTERFACE_MULTICAST &&
643 (flags & IFF_MULTICAST) &&
644 !(flags & IFF_LOOPBACK)) {
647 memcpy((char *)np->n_addr, (char *)ifaddr,
649 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
650 mreq.imr_interface.s_addr =
651 ((struct sockaddr_in *)np->n_addr)->sin_addr.s_addr;
652 if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP,
653 &mreq, sizeof(mreq)) < 0) {
655 "setsockopt IP_ADD_MEMBERSHIP: %m");
657 /* Fall back to broadcast on this if. */
658 np->n_flags &= ~IFF_MULTICAST;
665 np->n_next = neighbors;
674 Sendto(s, buf, cc, flags, to, tolen)
679 const struct sockaddr *to;
682 register struct whod *w = (struct whod *)buf;
683 register struct whoent *we;
684 struct sockaddr_in *sin = (struct sockaddr_in *)to;
686 printf("sendto %x.%d\n", ntohl(sin->sin_addr.s_addr),
687 ntohs(sin->sin_port));
688 printf("hostname %s %s\n", w->wd_hostname,
689 interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up"));
690 printf("load %4.2f, %4.2f, %4.2f\n",
691 ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0,
692 ntohl(w->wd_loadav[2]) / 100.0);
694 for (we = w->wd_we, cc /= sizeof(struct whoent); cc > 0; cc--, we++) {
695 time_t t = _time32_to_time(ntohl(we->we_utmp.out_time));
696 printf("%-8.8s %s:%s %.12s",
697 we->we_utmp.out_name,
698 w->wd_hostname, we->we_utmp.out_line,
700 we->we_idle = ntohl(we->we_idle) / 60;
702 if (we->we_idle >= 100*60)
703 we->we_idle = 100*60 - 1;
704 if (we->we_idle >= 60)
705 printf(" %2d", we->we_idle / 60);
708 printf(":%02d", we->we_idle % 60);
715 interval(time, updown)
719 static char resbuf[32];
720 int days, hours, minutes;
722 if (time < 0 || time > 3*30*24*60*60) {
723 (void) sprintf(resbuf, " %s ??:??", updown);
726 minutes = (time + 59) / 60; /* round to minutes */
727 hours = minutes / 60; minutes %= 60;
728 days = hours / 24; hours %= 24;
730 (void) sprintf(resbuf, "%s %2d+%02d:%02d",
731 updown, days, hours, minutes);
733 (void) sprintf(resbuf, "%s %2d:%02d",
734 updown, hours, minutes);