2 * Copyright (c) 1983, 1993 The Regents of the University of California.
3 * Copyright (c) 2013 Mariusz Zaborski <oshogbo@FreeBSD.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 4. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 static const char copyright[] =
33 "@(#) Copyright (c) 1983, 1993\n\
34 The Regents of the University of California. All rights reserved.\n";
39 static char sccsid[] = "@(#)rwhod.c 8.1 (Berkeley) 6/6/93";
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
46 #include <sys/capsicum.h>
47 #include <sys/param.h>
48 #include <sys/socket.h>
50 #include <sys/signal.h>
51 #include <sys/ioctl.h>
52 #include <sys/sysctl.h>
53 #include <sys/procdesc.h>
57 #include <net/if_dl.h>
58 #include <net/route.h>
59 #include <netinet/in.h>
60 #include <arpa/inet.h>
61 #include <protocols/rwhod.h>
79 #define UNPRIV_USER "daemon"
80 #define UNPRIV_GROUP "daemon"
82 #define NO_MULTICAST 0 /* multicast modes */
83 #define PER_INTERFACE_MULTICAST 1
84 #define SCOPED_MULTICAST 2
86 #define MAX_MULTICAST_SCOPE 32 /* "site-wide", by convention */
88 #define INADDR_WHOD_GROUP (u_long)0xe0000103 /* 224.0.1.3 */
89 /* (belongs in protocols/rwhod.h) */
93 int iff_flag = IFF_POINTOPOINT;
94 int multicast_mode = NO_MULTICAST;
96 struct sockaddr_in multicast_addr =
97 { sizeof(multicast_addr), AF_INET, 0, { 0 }, { 0 } };
100 * Sleep interval. Don't forget to change the down time check in ruptime
101 * if this is changed.
103 #define SL_INTERVAL (3 * 60)
105 char myname[MAXHOSTNAMELEN];
108 * We communicate with each neighbor in a list constructed at the time we're
109 * started up. Neighbors are currently directly connected via a hardware
113 struct neighbor *n_next;
114 char *n_name; /* interface name */
115 struct sockaddr *n_addr; /* who to send to */
116 int n_addrlen; /* size of address */
117 int n_flags; /* should forward?, interface flags */
120 struct neighbor *neighbors;
125 pid_t pid_child_receiver;
127 #define WHDRSIZE (int)(sizeof(mywd) - sizeof(mywd.wd_we))
129 int configure(int so);
130 void getboottime(int signo __unused);
131 void receiver_process(void);
132 void rt_xaddrs(caddr_t cp, caddr_t cplim, struct rt_addrinfo *rtinfo);
133 void run_as(uid_t *uid, gid_t *gid);
134 void quit(const char *msg);
135 void sender_process(void);
136 int verify(char *name, int maxlen);
137 static void usage(void);
140 char *interval(int time, char *updown);
141 void Sendto(int s, const void *buf, size_t cc, int flags,
142 const struct sockaddr *to, int tolen);
143 #define sendto Sendto
147 * This version of Berkeley's rwhod has been modified to use IP multicast
148 * datagrams, under control of a new command-line option:
150 * rwhod -m causes rwhod to use IP multicast (instead of
151 * broadcast or unicast) on all interfaces that have
152 * the IFF_MULTICAST flag set in their "ifnet" structs
153 * (excluding the loopback interface). The multicast
154 * reports are sent with a time-to-live of 1, to prevent
155 * forwarding beyond the directly-connected subnet(s).
157 * rwhod -m <ttl> causes rwhod to send IP multicast datagrams with a
158 * time-to-live of <ttl>, via a SINGLE interface rather
159 * than all interfaces. <ttl> must be between 0 and
160 * MAX_MULTICAST_SCOPE, defined below. Note that "-m 1"
161 * is different than "-m", in that "-m 1" specifies
162 * transmission on one interface only.
164 * When "-m" is used without a <ttl> argument, the program accepts multicast
165 * rwhod reports from all multicast-capable interfaces. If a <ttl> argument
166 * is given, it accepts multicast reports from only one interface, the one
167 * on which reports are sent (which may be controlled via the host's routing
168 * table). Regardless of the "-m" option, the program accepts broadcast or
169 * unicast reports from all interfaces. Thus, this program will hear the
170 * reports of old, non-multicasting rwhods, but, if multicasting is used,
171 * those old rwhods won't hear the reports generated by this program.
173 * -- Steve Deering, Stanford University, February 1989
176 main(int argc, char *argv[])
180 struct sockaddr_in soin;
186 errx(1, "not super user");
188 run_as(&unpriv_uid, &unpriv_gid);
192 while (argc > 0 && *argv[0] == '-') {
193 if (strcmp(*argv, "-m") == 0) {
194 if (argc > 1 && isdigit(*(argv + 1)[0])) {
197 multicast_mode = SCOPED_MULTICAST;
198 multicast_scope = atoi(*argv);
199 if (multicast_scope > MAX_MULTICAST_SCOPE) {
200 errx(1, "ttl must not exceed %u",
201 MAX_MULTICAST_SCOPE);
204 multicast_mode = PER_INTERFACE_MULTICAST;
206 } else if (strcmp(*argv, "-i") == 0) {
208 } else if (strcmp(*argv, "-l") == 0) {
210 } else if (strcmp(*argv, "-p") == 0) {
223 (void) signal(SIGHUP, getboottime);
224 openlog("rwhod", LOG_PID | LOG_NDELAY, LOG_DAEMON);
225 sp = getservbyname("who", "udp");
227 syslog(LOG_ERR, "who/udp: unknown service");
230 if (chdir(_PATH_RWHODIR) < 0) {
231 syslog(LOG_ERR, "%s: %m", _PATH_RWHODIR);
235 * Establish host name as returned by system.
237 if (gethostname(myname, sizeof(myname) - 1) < 0) {
238 syslog(LOG_ERR, "gethostname: %m");
241 if ((cp = strchr(myname, '.')) != NULL)
243 strlcpy(mywd.wd_hostname, myname, sizeof(mywd.wd_hostname));
245 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
246 syslog(LOG_ERR, "socket: %m");
249 if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0) {
250 syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
253 memset(&soin, 0, sizeof(soin));
254 soin.sin_len = sizeof(soin);
255 soin.sin_family = AF_INET;
256 soin.sin_port = sp->s_port;
257 if (bind(s, (struct sockaddr *)&soin, sizeof(soin)) < 0) {
258 syslog(LOG_ERR, "bind: %m");
261 if (setgid(unpriv_gid) != 0) {
262 syslog(LOG_ERR, "setgid: %m");
265 if (setgroups(1, &unpriv_gid) != 0) { /* XXX BOGUS groups[0] = egid */
266 syslog(LOG_ERR, "setgroups: %m");
269 if (setuid(unpriv_uid) != 0) {
270 syslog(LOG_ERR, "setuid: %m");
276 pid_child_receiver = pdfork(&fdp, 0);
277 if (pid_child_receiver == 0) {
279 } else if (pid_child_receiver > 0) {
281 } else if (pid_child_receiver == -1) {
282 if (errno == ENOSYS) {
284 "The pdfork(2) system call is not available - kernel too old.");
286 syslog(LOG_ERR, "pdfork: %m");
299 fprintf(stderr, "usage: rwhod [-i] [-p] [-l] [-m [ttl]]\n");
304 run_as(uid_t *uid, gid_t *gid)
309 pw = getpwnam(UNPRIV_USER);
311 syslog(LOG_ERR, "getpwnam(%s): %m", UNPRIV_USER);
316 gr = getgrnam(UNPRIV_GROUP);
318 syslog(LOG_ERR, "getgrnam(%s): %m", UNPRIV_GROUP);
325 * Check out host name for unprintables
326 * and other funnies before allowing a file
327 * to be created. Sorry, but blanks aren't allowed.
330 verify(char *name, int maxlen)
335 while (*name != '\0' && size < maxlen - 1) {
336 if (!isascii((unsigned char)*name) ||
337 !(isalnum((unsigned char)*name) ||
338 ispunct((unsigned char)*name))) {
349 receiver_process(void)
351 struct sockaddr_in from;
362 dirfd = open(".", O_RDONLY | O_DIRECTORY);
364 syslog(LOG_WARNING, "%s: %m", _PATH_RWHODIR);
367 cap_rights_init(&rights, CAP_CREATE, CAP_FSTAT, CAP_FTRUNCATE,
368 CAP_LOOKUP, CAP_SEEK, CAP_WRITE);
369 if (cap_rights_limit(dirfd, &rights) < 0 && errno != ENOSYS) {
370 syslog(LOG_WARNING, "cap_rights_limit: %m");
373 if (cap_enter() < 0 && errno != ENOSYS) {
374 syslog(LOG_ERR, "cap_enter: %m");
378 cc = recvfrom(s, &wd, sizeof(wd), 0, (struct sockaddr *)&from,
381 if (cc < 0 && errno != EINTR)
382 syslog(LOG_WARNING, "recv: %m");
385 if (from.sin_port != sp->s_port && !insecure_mode) {
386 syslog(LOG_WARNING, "%d: bad source port from %s",
387 ntohs(from.sin_port), inet_ntoa(from.sin_addr));
391 syslog(LOG_WARNING, "short packet from %s",
392 inet_ntoa(from.sin_addr));
395 if (wd.wd_vers != WHODVERSION)
397 if (wd.wd_type != WHODTYPE_STATUS)
399 if (!verify(wd.wd_hostname, sizeof(wd.wd_hostname))) {
400 syslog(LOG_WARNING, "malformed host name from %s",
401 inet_ntoa(from.sin_addr));
404 (void) snprintf(path, sizeof(path), "whod.%s", wd.wd_hostname);
406 * Rather than truncating and growing the file each time,
407 * use ftruncate if size is less than previous size.
409 whod = openat(dirfd, path, O_WRONLY | O_CREAT, 0644);
411 syslog(LOG_WARNING, "%s: %m", path);
414 cap_rights_init(&rights, CAP_FSTAT, CAP_FTRUNCATE, CAP_WRITE);
415 if (cap_rights_limit(whod, &rights) < 0 && errno != ENOSYS) {
416 syslog(LOG_WARNING, "cap_rights_limit: %m");
419 #if ENDIAN != BIG_ENDIAN
424 n = (cc - WHDRSIZE) / sizeof(struct whoent);
425 /* undo header byte swapping before writing to file */
426 wd.wd_sendtime = ntohl(wd.wd_sendtime);
427 for (i = 0; i < 3; i++)
428 wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]);
429 wd.wd_boottime = ntohl(wd.wd_boottime);
431 for (i = 0; i < n; i++) {
432 we->we_idle = ntohl(we->we_idle);
433 we->we_utmp.out_time =
434 ntohl(we->we_utmp.out_time);
440 wd.wd_recvtime = _time_to_int(t);
441 (void) write(whod, (char *)&wd, cc);
442 if (fstat(whod, &st) < 0 || st.st_size > cc)
459 struct whoent *we, *wend;
465 if (sendcount % 10 == 0)
468 wend = &mywd.wd_we[1024 / sizeof(struct whoent)];
470 while ((ut = getutxent()) != NULL && we < wend) {
471 if (ut->ut_type != USER_PROCESS)
473 strncpy(we->we_utmp.out_line, ut->ut_line,
474 sizeof(we->we_utmp.out_line));
475 strncpy(we->we_utmp.out_name, ut->ut_user,
476 sizeof(we->we_utmp.out_name));
477 we->we_utmp.out_time =
478 htonl(_time_to_time32(ut->ut_tv.tv_sec));
483 if (chdir(_PATH_DEV) < 0) {
484 syslog(LOG_ERR, "chdir(%s): %m", _PATH_DEV);
488 for (we = mywd.wd_we; we < wend; we++) {
489 if (stat(we->we_utmp.out_line, &stb) >= 0)
490 we->we_idle = htonl(now - stb.st_atime);
492 (void) getloadavg(avenrun,
493 sizeof(avenrun) / sizeof(avenrun[0]));
494 for (i = 0; i < 3; i++)
495 mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100));
496 cc = (char *)wend - (char *)&mywd;
497 mywd.wd_sendtime = htonl(_time_to_time32(time(NULL)));
498 mywd.wd_vers = WHODVERSION;
499 mywd.wd_type = WHODTYPE_STATUS;
500 if (multicast_mode == SCOPED_MULTICAST) {
501 (void) sendto(s, (char *)&mywd, cc, 0,
502 (struct sockaddr *)&multicast_addr,
503 sizeof(multicast_addr));
505 for (np = neighbors; np != NULL; np = np->n_next) {
506 if (multicast_mode == PER_INTERFACE_MULTICAST &&
507 (np->n_flags & IFF_MULTICAST) != 0) {
509 * Select the outgoing interface for the
512 if (setsockopt(s, IPPROTO_IP,
514 &(((struct sockaddr_in *)np->n_addr)->sin_addr),
515 sizeof(struct in_addr)) < 0) {
517 "setsockopt IP_MULTICAST_IF: %m");
520 (void) sendto(s, (char *)&mywd, cc, 0,
521 (struct sockaddr *)&multicast_addr,
522 sizeof(multicast_addr));
524 (void) sendto(s, (char *)&mywd, cc, 0,
525 np->n_addr, np->n_addrlen);
529 if (chdir(_PATH_RWHODIR) < 0) {
530 syslog(LOG_ERR, "chdir(%s): %m", _PATH_RWHODIR);
533 if (waitpid(pid_child_receiver, &status, WNOHANG) ==
534 pid_child_receiver) {
542 getboottime(int signo __unused)
549 mib[1] = KERN_BOOTTIME;
551 if (sysctl(mib, 2, &tm, &size, NULL, 0) == -1) {
552 syslog(LOG_ERR, "cannot get boottime: %m");
555 mywd.wd_boottime = htonl(_time_to_time32(tm.tv_sec));
559 quit(const char *msg)
562 syslog(LOG_ERR, "%s", msg);
567 rt_xaddrs(caddr_t cp, caddr_t cplim, struct rt_addrinfo *rtinfo)
572 memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
573 for (i = 0; i < RTAX_MAX && cp < cplim; i++) {
574 if ((rtinfo->rti_addrs & (1 << i)) == 0)
576 sa = (struct sockaddr *)cp;
577 rtinfo->rti_info[i] = sa;
583 * Figure out device configuration and select
584 * networks which deserve status information.
590 struct if_msghdr *ifm;
591 struct ifa_msghdr *ifam;
592 struct sockaddr_dl *sdl;
594 int mib[6], flags, lflags, len;
595 char *buf, *lim, *next;
596 struct rt_addrinfo info;
599 if (multicast_mode != NO_MULTICAST) {
600 multicast_addr.sin_addr.s_addr = htonl(INADDR_WHOD_GROUP);
601 multicast_addr.sin_port = sp->s_port;
604 if (multicast_mode == SCOPED_MULTICAST) {
608 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
609 mreq.imr_interface.s_addr = htonl(INADDR_ANY);
610 if (setsockopt(so, IPPROTO_IP, IP_ADD_MEMBERSHIP,
611 &mreq, sizeof(mreq)) < 0) {
613 "setsockopt IP_ADD_MEMBERSHIP: %m");
616 ttl = multicast_scope;
617 if (setsockopt(so, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
620 "setsockopt IP_MULTICAST_TTL: %m");
630 mib[4] = NET_RT_IFLIST;
632 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
633 quit("route-sysctl-estimate");
634 if ((buf = malloc(needed)) == NULL)
636 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
637 quit("actual retrieval of interface table");
640 sdl = NULL; /* XXX just to keep gcc -Wall happy */
641 for (next = buf; next < lim; next += ifm->ifm_msglen) {
642 ifm = (struct if_msghdr *)next;
643 if (ifm->ifm_type == RTM_IFINFO) {
644 sdl = (struct sockaddr_dl *)(ifm + 1);
645 flags = ifm->ifm_flags;
648 if ((flags & IFF_UP) == 0)
650 lflags = IFF_BROADCAST | iff_flag;
651 if (multicast_mode == PER_INTERFACE_MULTICAST)
652 lflags |= IFF_MULTICAST;
653 if ((flags & lflags) == 0)
655 if (ifm->ifm_type != RTM_NEWADDR)
656 quit("out of sync parsing NET_RT_IFLIST");
657 ifam = (struct ifa_msghdr *)ifm;
658 info.rti_addrs = ifam->ifam_addrs;
659 rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam,
661 /* gag, wish we could get rid of Internet dependencies */
662 #define dstaddr info.rti_info[RTAX_BRD]
663 #define ifaddr info.rti_info[RTAX_IFA]
664 #define IPADDR_SA(x) ((struct sockaddr_in *)(x))->sin_addr.s_addr
665 #define PORT_SA(x) ((struct sockaddr_in *)(x))->sin_port
666 if (dstaddr == 0 || dstaddr->sa_family != AF_INET)
668 PORT_SA(dstaddr) = sp->s_port;
669 for (np = neighbors; np != NULL; np = np->n_next) {
670 if (memcmp(sdl->sdl_data, np->n_name,
671 sdl->sdl_nlen) == 0 &&
672 IPADDR_SA(np->n_addr) == IPADDR_SA(dstaddr)) {
678 len = sizeof(*np) + dstaddr->sa_len + sdl->sdl_nlen + 1;
681 quit("malloc of neighbor structure");
684 np->n_addr = (struct sockaddr *)(np + 1);
685 np->n_addrlen = dstaddr->sa_len;
686 np->n_name = np->n_addrlen + (char *)np->n_addr;
687 memcpy((char *)np->n_addr, (char *)dstaddr, np->n_addrlen);
688 memcpy(np->n_name, sdl->sdl_data, sdl->sdl_nlen);
689 if (multicast_mode == PER_INTERFACE_MULTICAST &&
690 (flags & IFF_MULTICAST) != 0 &&
691 (flags & IFF_LOOPBACK) == 0) {
694 memcpy((char *)np->n_addr, (char *)ifaddr,
696 mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
697 mreq.imr_interface.s_addr =
698 ((struct sockaddr_in *)np->n_addr)->sin_addr.s_addr;
699 if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP,
700 &mreq, sizeof(mreq)) < 0) {
702 "setsockopt IP_ADD_MEMBERSHIP: %m");
704 /* Fall back to broadcast on this if. */
705 np->n_flags &= ~IFF_MULTICAST;
712 np->n_next = neighbors;
721 Sendto(int s, const void *buf, size_t cc, int flags, const struct sockaddr *to,
726 struct sockaddr_in *sin;
728 w = (struct whod *)buf;
729 sin = (struct sockaddr_in *)to;
730 printf("sendto %x.%d\n", ntohl(sin->sin_addr.s_addr),
731 ntohs(sin->sin_port));
732 printf("hostname %s %s\n", w->wd_hostname,
733 interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up"));
734 printf("load %4.2f, %4.2f, %4.2f\n",
735 ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0,
736 ntohl(w->wd_loadav[2]) / 100.0);
738 for (we = w->wd_we, cc /= sizeof(struct whoent); cc > 0; cc--, we++) {
739 time_t t = _time32_to_time(ntohl(we->we_utmp.out_time));
741 printf("%-8.8s %s:%s %.12s", we->we_utmp.out_name,
742 w->wd_hostname, we->we_utmp.out_line, ctime(&t) + 4);
743 we->we_idle = ntohl(we->we_idle) / 60;
744 if (we->we_idle != 0) {
745 if (we->we_idle >= 100 * 60)
746 we->we_idle = 100 * 60 - 1;
747 if (we->we_idle >= 60)
748 printf(" %2d", we->we_idle / 60);
751 printf(":%02d", we->we_idle % 60);
758 interval(int time, char *updown)
760 static char resbuf[32];
761 int days, hours, minutes;
763 if (time < 0 || time > 3 * 30 * 24 * 60 * 60) {
764 (void) sprintf(resbuf, " %s ??:??", updown);
767 minutes = (time + 59) / 60; /* round to minutes */
768 hours = minutes / 60;
773 (void) sprintf(resbuf, "%s %2d+%02d:%02d",
774 updown, days, hours, minutes);
776 (void) sprintf(resbuf, "%s %2d:%02d",
777 updown, hours, minutes);