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 * 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
35 static const char copyright[] =
36 "@(#) Copyright (c) 1983, 1993\n\
37 The Regents of the University of California. All rights reserved.\n";
42 static char sccsid[] = "@(#)rwhod.c 8.1 (Berkeley) 6/6/93";
44 static const char rcsid[] =
45 "$FreeBSD: src/usr.sbin/rwhod/rwhod.c,v 1.13.2.2 2000/12/23 15:28:12 iedowse Exp $";
48 #include <sys/param.h>
49 #include <sys/socket.h>
51 #include <sys/signal.h>
52 #include <sys/ioctl.h>
53 #include <sys/sysctl.h>
56 #include <net/if_dl.h>
57 #include <net/route.h>
58 #include <netinet/in.h>
59 #include <arpa/inet.h>
60 #include <protocols/rwhod.h>
78 * This version of Berkeley's rwhod has been modified to use IP multicast
79 * datagrams, under control of a new command-line option:
81 * rwhod -m causes rwhod to use IP multicast (instead of
82 * broadcast or unicast) on all interfaces that have
83 * the IFF_MULTICAST flag set in their "ifnet" structs
84 * (excluding the loopback interface). The multicast
85 * reports are sent with a time-to-live of 1, to prevent
86 * forwarding beyond the directly-connected subnet(s).
88 * rwhod -m <ttl> causes rwhod to send IP multicast datagrams with a
89 * time-to-live of <ttl>, via a SINGLE interface rather
90 * than all interfaces. <ttl> must be between 0 and
91 * MAX_MULTICAST_SCOPE, defined below. Note that "-m 1"
92 * is different than "-m", in that "-m 1" specifies
93 * transmission on one interface only.
95 * When "-m" is used without a <ttl> argument, the program accepts multicast
96 * rwhod reports from all multicast-capable interfaces. If a <ttl> argument
97 * is given, it accepts multicast reports from only one interface, the one
98 * on which reports are sent (which may be controlled via the host's routing
99 * table). Regardless of the "-m" option, the program accepts broadcast or
100 * unicast reports from all interfaces. Thus, this program will hear the
101 * reports of old, non-multicasting rwhods, but, if multicasting is used,
102 * those old rwhods won't hear the reports generated by this program.
104 * -- Steve Deering, Stanford University, February 1989
107 #define UNPRIV_USER "daemon"
108 #define UNPRIV_GROUP "daemon"
110 #define NO_MULTICAST 0 /* multicast modes */
111 #define PER_INTERFACE_MULTICAST 1
112 #define SCOPED_MULTICAST 2
114 #define MAX_MULTICAST_SCOPE 32 /* "site-wide", by convention */
116 #define INADDR_WHOD_GROUP (u_long)0xe0000103 /* 224.0.1.3 */
117 /* (belongs in protocols/rwhod.h) */
121 int iff_flag = IFF_POINTOPOINT;
122 int multicast_mode = NO_MULTICAST;
124 struct sockaddr_in multicast_addr = { sizeof multicast_addr, AF_INET };
127 * Alarm interval. Don't forget to change the down time check in ruptime
128 * if this is changed.
130 #define AL_INTERVAL (3 * 60)
132 char myname[MAXHOSTNAMELEN];
135 * We communicate with each neighbor in a list constructed at the time we're
136 * started up. Neighbors are currently directly connected via a hardware
140 struct neighbor *n_next;
141 char *n_name; /* interface name */
142 struct sockaddr *n_addr; /* who to send to */
143 int n_addrlen; /* size of address */
144 int n_flags; /* should forward?, interface flags */
147 struct neighbor *neighbors;
152 #define WHDRSIZE (sizeof(mywd) - sizeof(mywd.wd_we))
154 void run_as __P((uid_t *, gid_t *));
155 int configure __P((int));
156 void getboottime __P((int));
157 void onalrm __P((int));
158 void quit __P((char *));
159 void rt_xaddrs __P((caddr_t, caddr_t, struct rt_addrinfo *));
160 int verify __P((char *, int));
161 static void usage __P((void));
163 char *interval __P((int, char *));
164 void Sendto __P((int, const void *, size_t, int,
165 const struct sockaddr *, int));
166 #define sendto Sendto
174 struct sockaddr_in from;
179 struct sockaddr_in sin;
184 errx(1, "not super user");
186 run_as(&unpriv_uid, &unpriv_gid);
189 while (argc > 0 && *argv[0] == '-') {
190 if (strcmp(*argv, "-m") == 0) {
191 if (argc > 1 && isdigit(*(argv + 1)[0])) {
193 multicast_mode = SCOPED_MULTICAST;
194 multicast_scope = atoi(*argv);
195 if (multicast_scope > MAX_MULTICAST_SCOPE)
196 errx(1, "ttl must not exceed %u",
197 MAX_MULTICAST_SCOPE);
199 else multicast_mode = PER_INTERFACE_MULTICAST;
201 else if (strcmp(*argv, "-i") == 0)
203 else if (strcmp(*argv, "-l") == 0)
205 else if (strcmp(*argv, "-p") == 0)
216 (void) signal(SIGHUP, getboottime);
217 openlog("rwhod", LOG_PID, LOG_DAEMON);
218 sp = getservbyname("who", "udp");
220 syslog(LOG_ERR, "udp/who: unknown service");
223 if (chdir(_PATH_RWHODIR) < 0) {
224 syslog(LOG_ERR, "%s: %m", _PATH_RWHODIR);
228 * Establish host name as returned by system.
230 if (gethostname(myname, sizeof(myname) - 1) < 0) {
231 syslog(LOG_ERR, "gethostname: %m");
234 if ((cp = index(myname, '.')) != NULL)
236 strncpy(mywd.wd_hostname, myname, sizeof(mywd.wd_hostname) - 1);
237 mywd.wd_hostname[sizeof(mywd.wd_hostname) - 1] = '\0';
238 utmpf = open(_PATH_UTMP, O_RDONLY|O_CREAT, 0644);
240 syslog(LOG_ERR, "%s: %m", _PATH_UTMP);
244 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
245 syslog(LOG_ERR, "socket: %m");
248 if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0) {
249 syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
252 memset(&sin, 0, sizeof(sin));
253 sin.sin_len = sizeof(sin);
254 sin.sin_family = AF_INET;
255 sin.sin_port = sp->s_port;
256 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
257 syslog(LOG_ERR, "bind: %m");
261 setgroups(1, &unpriv_gid); /* XXX BOGUS groups[0] = egid */
266 signal(SIGALRM, onalrm);
271 int cc, whod, len = sizeof(from);
273 cc = recvfrom(s, (char *)&wd, sizeof(struct whod), 0,
274 (struct sockaddr *)&from, &len);
276 if (cc < 0 && errno != EINTR)
277 syslog(LOG_WARNING, "recv: %m");
280 if (from.sin_port != sp->s_port && !insecure_mode) {
281 syslog(LOG_WARNING, "%d: bad source port from %s",
282 ntohs(from.sin_port), inet_ntoa(from.sin_addr));
286 syslog(LOG_WARNING, "short packet from %s",
287 inet_ntoa(from.sin_addr));
290 if (wd.wd_vers != WHODVERSION)
292 if (wd.wd_type != WHODTYPE_STATUS)
294 if (!verify(wd.wd_hostname, sizeof wd.wd_hostname)) {
295 syslog(LOG_WARNING, "malformed host name from %s",
296 inet_ntoa(from.sin_addr));
299 (void) snprintf(path, sizeof path, "whod.%s", wd.wd_hostname);
301 * Rather than truncating and growing the file each time,
302 * use ftruncate if size is less than previous size.
304 whod = open(path, O_WRONLY | O_CREAT, 0644);
306 syslog(LOG_WARNING, "%s: %m", path);
309 #if ENDIAN != BIG_ENDIAN
311 int i, n = (cc - WHDRSIZE)/sizeof(struct whoent);
314 /* undo header byte swapping before writing to file */
315 wd.wd_sendtime = ntohl(wd.wd_sendtime);
316 for (i = 0; i < 3; i++)
317 wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]);
318 wd.wd_boottime = ntohl(wd.wd_boottime);
320 for (i = 0; i < n; i++) {
321 we->we_idle = ntohl(we->we_idle);
322 we->we_utmp.out_time =
323 ntohl(we->we_utmp.out_time);
328 (void) time((time_t *)&wd.wd_recvtime);
329 (void) write(whod, (char *)&wd, cc);
330 if (fstat(whod, &st) < 0 || st.st_size > cc)
339 fprintf(stderr, "usage: rwhod [-i] [-p] [-l] [-m [ttl]]\n");
351 pw = getpwnam(UNPRIV_USER);
353 syslog(LOG_ERR, "getpwnam(%s): %m", UNPRIV_USER);
358 gr = getgrnam(UNPRIV_GROUP);
360 syslog(LOG_ERR, "getgrnam(%s): %m", UNPRIV_GROUP);
367 * Check out host name for unprintables
368 * and other funnies before allowing a file
369 * to be created. Sorry, but blanks aren't allowed.
376 register int size = 0;
378 while (*name && size < maxlen - 1) {
379 if (!isascii(*name) || !(isalnum(*name) || ispunct(*name)))
397 register struct neighbor *np;
398 register struct whoent *we = mywd.wd_we, *wlast;
406 if (alarmcount % 10 == 0)
409 (void) fstat(utmpf, &stb);
410 if ((stb.st_mtime != utmptime) || (stb.st_size > utmpsize)) {
411 utmptime = stb.st_mtime;
412 if (stb.st_size > utmpsize) {
413 utmpsize = stb.st_size + 10 * sizeof(struct utmp);
415 utmp = (struct utmp *)realloc(utmp, utmpsize);
417 utmp = (struct utmp *)malloc(utmpsize);
419 syslog(LOG_WARNING, "malloc failed");
424 (void) lseek(utmpf, (off_t)0, L_SET);
425 cc = read(utmpf, (char *)utmp, stb.st_size);
427 syslog(LOG_ERR, "read(%s): %m", _PATH_UTMP);
430 wlast = &mywd.wd_we[1024 / sizeof(struct whoent) - 1];
431 utmpent = cc / sizeof(struct utmp);
432 for (i = 0; i < utmpent; i++)
433 if (utmp[i].ut_name[0]) {
434 memcpy(we->we_utmp.out_line, utmp[i].ut_line,
435 sizeof(utmp[i].ut_line));
436 memcpy(we->we_utmp.out_name, utmp[i].ut_name,
437 sizeof(utmp[i].ut_name));
438 we->we_utmp.out_time = htonl(utmp[i].ut_time);
443 utmpent = we - mywd.wd_we;
447 * The test on utmpent looks silly---after all, if no one is
448 * logged on, why worry about efficiency?---but is useful on
449 * (e.g.) compute servers.
451 if (utmpent && chdir(_PATH_DEV)) {
452 syslog(LOG_ERR, "chdir(%s): %m", _PATH_DEV);
456 for (i = 0; i < utmpent; i++) {
457 if (stat(we->we_utmp.out_line, &stb) >= 0)
458 we->we_idle = htonl(now - stb.st_atime);
461 (void)getloadavg(avenrun, sizeof(avenrun)/sizeof(avenrun[0]));
462 for (i = 0; i < 3; i++)
463 mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100));
464 cc = (char *)we - (char *)&mywd;
465 mywd.wd_sendtime = htonl(time(0));
466 mywd.wd_vers = WHODVERSION;
467 mywd.wd_type = WHODTYPE_STATUS;
468 if (multicast_mode == SCOPED_MULTICAST) {
469 (void) sendto(s, (char *)&mywd, cc, 0,
470 (struct sockaddr *)&multicast_addr,
471 sizeof(multicast_addr));
473 else for (np = neighbors; np != NULL; np = np->n_next) {
474 if (multicast_mode == PER_INTERFACE_MULTICAST &&
475 np->n_flags & IFF_MULTICAST) {
477 * Select the outgoing interface for the multicast.
479 if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
480 &(((struct sockaddr_in *)np->n_addr)->sin_addr),
481 sizeof(struct in_addr)) < 0) {
483 "setsockopt IP_MULTICAST_IF: %m");
486 (void) sendto(s, (char *)&mywd, cc, 0,
487 (struct sockaddr *)&multicast_addr,
488 sizeof(multicast_addr));
489 } else (void) sendto(s, (char *)&mywd, cc, 0,
490 np->n_addr, np->n_addrlen);
492 if (utmpent && chdir(_PATH_RWHODIR)) {
493 syslog(LOG_ERR, "chdir(%s): %m", _PATH_RWHODIR);
497 (void) alarm(AL_INTERVAL);
509 mib[1] = KERN_BOOTTIME;
511 if (sysctl(mib, 2, &tm, &size, NULL, 0) == -1) {
512 syslog(LOG_ERR, "cannot get boottime: %m");
515 mywd.wd_boottime = htonl(tm.tv_sec);
522 syslog(LOG_ERR, "%s", msg);
527 ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
528 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
531 rt_xaddrs(cp, cplim, rtinfo)
532 register caddr_t cp, cplim;
533 register struct rt_addrinfo *rtinfo;
535 register struct sockaddr *sa;
538 memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
539 for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
540 if ((rtinfo->rti_addrs & (1 << i)) == 0)
542 rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
548 * Figure out device configuration and select
549 * networks which deserve status information.
555 register struct neighbor *np;
556 register struct if_msghdr *ifm;
557 register struct ifa_msghdr *ifam;
558 struct sockaddr_dl *sdl;
560 int mib[6], flags = 0, len;
561 char *buf, *lim, *next;
562 struct rt_addrinfo info;
564 if (multicast_mode != NO_MULTICAST) {
565 multicast_addr.sin_addr.s_addr = htonl(INADDR_WHOD_GROUP);
566 multicast_addr.sin_port = sp->s_port;
569 if (multicast_mode == SCOPED_MULTICAST) {
573 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
574 mreq.imr_interface.s_addr = htonl(INADDR_ANY);
575 if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP,
576 &mreq, sizeof(mreq)) < 0) {
578 "setsockopt IP_ADD_MEMBERSHIP: %m");
581 ttl = multicast_scope;
582 if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
583 &ttl, sizeof(ttl)) < 0) {
585 "setsockopt IP_MULTICAST_TTL: %m");
595 mib[4] = NET_RT_IFLIST;
597 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
598 quit("route-sysctl-estimate");
599 if ((buf = malloc(needed)) == NULL)
601 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
602 quit("actual retrieval of interface table");
605 sdl = NULL; /* XXX just to keep gcc -Wall happy */
606 for (next = buf; next < lim; next += ifm->ifm_msglen) {
607 ifm = (struct if_msghdr *)next;
608 if (ifm->ifm_type == RTM_IFINFO) {
609 sdl = (struct sockaddr_dl *)(ifm + 1);
610 flags = ifm->ifm_flags;
613 if ((flags & IFF_UP) == 0 ||
614 (flags & (((multicast_mode == PER_INTERFACE_MULTICAST) ?
616 IFF_BROADCAST|iff_flag)) == 0)
618 if (ifm->ifm_type != RTM_NEWADDR)
619 quit("out of sync parsing NET_RT_IFLIST");
620 ifam = (struct ifa_msghdr *)ifm;
621 info.rti_addrs = ifam->ifam_addrs;
622 rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam,
624 /* gag, wish we could get rid of Internet dependencies */
625 #define dstaddr info.rti_info[RTAX_BRD]
626 #define ifaddr info.rti_info[RTAX_IFA]
627 #define IPADDR_SA(x) ((struct sockaddr_in *)(x))->sin_addr.s_addr
628 #define PORT_SA(x) ((struct sockaddr_in *)(x))->sin_port
629 if (dstaddr == 0 || dstaddr->sa_family != AF_INET)
631 PORT_SA(dstaddr) = sp->s_port;
632 for (np = neighbors; np != NULL; np = np->n_next)
633 if (memcmp(sdl->sdl_data, np->n_name,
634 sdl->sdl_nlen) == 0 &&
635 IPADDR_SA(np->n_addr) == IPADDR_SA(dstaddr))
639 len = sizeof(*np) + dstaddr->sa_len + sdl->sdl_nlen + 1;
640 np = (struct neighbor *)malloc(len);
642 quit("malloc of neighbor structure");
645 np->n_addr = (struct sockaddr *)(np + 1);
646 np->n_addrlen = dstaddr->sa_len;
647 np->n_name = np->n_addrlen + (char *)np->n_addr;
648 memcpy((char *)np->n_addr, (char *)dstaddr, np->n_addrlen);
649 memcpy(np->n_name, sdl->sdl_data, sdl->sdl_nlen);
650 if (multicast_mode == PER_INTERFACE_MULTICAST &&
651 (flags & IFF_MULTICAST) &&
652 !(flags & IFF_LOOPBACK)) {
655 memcpy((char *)np->n_addr, (char *)ifaddr,
657 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
658 mreq.imr_interface.s_addr =
659 ((struct sockaddr_in *)np->n_addr)->sin_addr.s_addr;
660 if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP,
661 &mreq, sizeof(mreq)) < 0) {
663 "setsockopt IP_ADD_MEMBERSHIP: %m");
665 /* Fall back to broadcast on this if. */
666 np->n_flags &= ~IFF_MULTICAST;
673 np->n_next = neighbors;
682 Sendto(s, buf, cc, flags, to, tolen)
687 const struct sockaddr *to;
690 register struct whod *w = (struct whod *)buf;
691 register struct whoent *we;
692 struct sockaddr_in *sin = (struct sockaddr_in *)to;
694 printf("sendto %x.%d\n", ntohl(sin->sin_addr.s_addr),
695 ntohs(sin->sin_port));
696 printf("hostname %s %s\n", w->wd_hostname,
697 interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up"));
698 printf("load %4.2f, %4.2f, %4.2f\n",
699 ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0,
700 ntohl(w->wd_loadav[2]) / 100.0);
702 for (we = w->wd_we, cc /= sizeof(struct whoent); cc > 0; cc--, we++) {
703 time_t t = ntohl(we->we_utmp.out_time);
704 printf("%-8.8s %s:%s %.12s",
705 we->we_utmp.out_name,
706 w->wd_hostname, we->we_utmp.out_line,
708 we->we_idle = ntohl(we->we_idle) / 60;
710 if (we->we_idle >= 100*60)
711 we->we_idle = 100*60 - 1;
712 if (we->we_idle >= 60)
713 printf(" %2d", we->we_idle / 60);
716 printf(":%02d", we->we_idle % 60);
723 interval(time, updown)
727 static char resbuf[32];
728 int days, hours, minutes;
730 if (time < 0 || time > 3*30*24*60*60) {
731 (void) sprintf(resbuf, " %s ??:??", updown);
734 minutes = (time + 59) / 60; /* round to minutes */
735 hours = minutes / 60; minutes %= 60;
736 days = hours / 24; hours %= 24;
738 (void) sprintf(resbuf, "%s %2d+%02d:%02d",
739 updown, days, hours, minutes);
741 (void) sprintf(resbuf, "%s %2d:%02d",
742 updown, hours, minutes);