| Current Path : /usr/src/usr.sbin/rwhod/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/usr.sbin/rwhod/rwhod.c |
/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1983, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#if 0
#ifndef lint
static char sccsid[] = "@(#)rwhod.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/usr.sbin/rwhod/rwhod.c 220969 2011-04-23 13:42:03Z simon $");
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/signal.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <protocols/rwhod.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <timeconv.h>
#include <unistd.h>
#include <utmpx.h>
#include <pwd.h>
#include <grp.h>
/*
* This version of Berkeley's rwhod has been modified to use IP multicast
* datagrams, under control of a new command-line option:
*
* rwhod -m causes rwhod to use IP multicast (instead of
* broadcast or unicast) on all interfaces that have
* the IFF_MULTICAST flag set in their "ifnet" structs
* (excluding the loopback interface). The multicast
* reports are sent with a time-to-live of 1, to prevent
* forwarding beyond the directly-connected subnet(s).
*
* rwhod -m <ttl> causes rwhod to send IP multicast datagrams with a
* time-to-live of <ttl>, via a SINGLE interface rather
* than all interfaces. <ttl> must be between 0 and
* MAX_MULTICAST_SCOPE, defined below. Note that "-m 1"
* is different than "-m", in that "-m 1" specifies
* transmission on one interface only.
*
* When "-m" is used without a <ttl> argument, the program accepts multicast
* rwhod reports from all multicast-capable interfaces. If a <ttl> argument
* is given, it accepts multicast reports from only one interface, the one
* on which reports are sent (which may be controlled via the host's routing
* table). Regardless of the "-m" option, the program accepts broadcast or
* unicast reports from all interfaces. Thus, this program will hear the
* reports of old, non-multicasting rwhods, but, if multicasting is used,
* those old rwhods won't hear the reports generated by this program.
*
* -- Steve Deering, Stanford University, February 1989
*/
#define UNPRIV_USER "daemon"
#define UNPRIV_GROUP "daemon"
#define NO_MULTICAST 0 /* multicast modes */
#define PER_INTERFACE_MULTICAST 1
#define SCOPED_MULTICAST 2
#define MAX_MULTICAST_SCOPE 32 /* "site-wide", by convention */
#define INADDR_WHOD_GROUP (u_long)0xe0000103 /* 224.0.1.3 */
/* (belongs in protocols/rwhod.h) */
int insecure_mode;
int quiet_mode;
int iff_flag = IFF_POINTOPOINT;
int multicast_mode = NO_MULTICAST;
int multicast_scope;
struct sockaddr_in multicast_addr =
{ sizeof multicast_addr, AF_INET, 0, { 0 }, { 0 } };
/*
* Alarm interval. Don't forget to change the down time check in ruptime
* if this is changed.
*/
#define AL_INTERVAL (3 * 60)
char myname[MAXHOSTNAMELEN];
/*
* We communicate with each neighbor in a list constructed at the time we're
* started up. Neighbors are currently directly connected via a hardware
* interface.
*/
struct neighbor {
struct neighbor *n_next;
char *n_name; /* interface name */
struct sockaddr *n_addr; /* who to send to */
int n_addrlen; /* size of address */
int n_flags; /* should forward?, interface flags */
};
struct neighbor *neighbors;
struct whod mywd;
struct servent *sp;
int s;
#define WHDRSIZE (int)(sizeof(mywd) - sizeof(mywd.wd_we))
void run_as(uid_t *, gid_t *);
int configure(int);
void getboottime(int);
void onalrm(int);
void quit(const char *);
void rt_xaddrs(caddr_t, caddr_t, struct rt_addrinfo *);
int verify(char *, int);
static void usage(void);
#ifdef DEBUG
char *interval(int, char *);
void Sendto(int, const void *, size_t, int, const struct sockaddr *, int);
#define sendto Sendto
#endif
int
main(int argc, char *argv[])
{
struct sockaddr_in from;
struct stat st;
char path[64];
int on = 1;
char *cp;
struct sockaddr_in soin;
uid_t unpriv_uid;
gid_t unpriv_gid;
if (getuid())
errx(1, "not super user");
run_as(&unpriv_uid, &unpriv_gid);
argv++; argc--;
while (argc > 0 && *argv[0] == '-') {
if (strcmp(*argv, "-m") == 0) {
if (argc > 1 && isdigit(*(argv + 1)[0])) {
argv++, argc--;
multicast_mode = SCOPED_MULTICAST;
multicast_scope = atoi(*argv);
if (multicast_scope > MAX_MULTICAST_SCOPE)
errx(1, "ttl must not exceed %u",
MAX_MULTICAST_SCOPE);
}
else multicast_mode = PER_INTERFACE_MULTICAST;
}
else if (strcmp(*argv, "-i") == 0)
insecure_mode = 1;
else if (strcmp(*argv, "-l") == 0)
quiet_mode = 1;
else if (strcmp(*argv, "-p") == 0)
iff_flag = 0;
else
usage();
argv++, argc--;
}
if (argc > 0)
usage();
#ifndef DEBUG
daemon(1, 0);
#endif
(void) signal(SIGHUP, getboottime);
openlog("rwhod", LOG_PID, LOG_DAEMON);
sp = getservbyname("who", "udp");
if (sp == NULL) {
syslog(LOG_ERR, "who/udp: unknown service");
exit(1);
}
if (chdir(_PATH_RWHODIR) < 0) {
syslog(LOG_ERR, "%s: %m", _PATH_RWHODIR);
exit(1);
}
/*
* Establish host name as returned by system.
*/
if (gethostname(myname, sizeof(myname) - 1) < 0) {
syslog(LOG_ERR, "gethostname: %m");
exit(1);
}
if ((cp = index(myname, '.')) != NULL)
*cp = '\0';
strncpy(mywd.wd_hostname, myname, sizeof(mywd.wd_hostname) - 1);
mywd.wd_hostname[sizeof(mywd.wd_hostname) - 1] = '\0';
getboottime(0);
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
syslog(LOG_ERR, "socket: %m");
exit(1);
}
if (setsockopt(s, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)) < 0) {
syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
exit(1);
}
memset(&soin, 0, sizeof(soin));
soin.sin_len = sizeof(soin);
soin.sin_family = AF_INET;
soin.sin_port = sp->s_port;
if (bind(s, (struct sockaddr *)&soin, sizeof(soin)) < 0) {
syslog(LOG_ERR, "bind: %m");
exit(1);
}
if (setgid(unpriv_gid) != 0) {
syslog(LOG_ERR, "setgid: %m");
exit(1);
}
if (setgroups(1, &unpriv_gid) != 0) { /* XXX BOGUS groups[0] = egid */
syslog(LOG_ERR, "setgroups: %m");
exit(1);
}
if (setuid(unpriv_uid) != 0) {
syslog(LOG_ERR, "setuid: %m");
exit(1);
}
if (!configure(s))
exit(1);
if (!quiet_mode) {
signal(SIGALRM, onalrm);
onalrm(0);
}
for (;;) {
struct whod wd;
socklen_t len = sizeof(from);
int cc, whod;
time_t t;
cc = recvfrom(s, (char *)&wd, sizeof(struct whod), 0,
(struct sockaddr *)&from, &len);
if (cc <= 0) {
if (cc < 0 && errno != EINTR)
syslog(LOG_WARNING, "recv: %m");
continue;
}
if (from.sin_port != sp->s_port && !insecure_mode) {
syslog(LOG_WARNING, "%d: bad source port from %s",
ntohs(from.sin_port), inet_ntoa(from.sin_addr));
continue;
}
if (cc < WHDRSIZE) {
syslog(LOG_WARNING, "short packet from %s",
inet_ntoa(from.sin_addr));
continue;
}
if (wd.wd_vers != WHODVERSION)
continue;
if (wd.wd_type != WHODTYPE_STATUS)
continue;
if (!verify(wd.wd_hostname, sizeof wd.wd_hostname)) {
syslog(LOG_WARNING, "malformed host name from %s",
inet_ntoa(from.sin_addr));
continue;
}
(void) snprintf(path, sizeof path, "whod.%s", wd.wd_hostname);
/*
* Rather than truncating and growing the file each time,
* use ftruncate if size is less than previous size.
*/
whod = open(path, O_WRONLY | O_CREAT, 0644);
if (whod < 0) {
syslog(LOG_WARNING, "%s: %m", path);
continue;
}
#if ENDIAN != BIG_ENDIAN
{
int i, n = (cc - WHDRSIZE)/sizeof(struct whoent);
struct whoent *we;
/* undo header byte swapping before writing to file */
wd.wd_sendtime = ntohl(wd.wd_sendtime);
for (i = 0; i < 3; i++)
wd.wd_loadav[i] = ntohl(wd.wd_loadav[i]);
wd.wd_boottime = ntohl(wd.wd_boottime);
we = wd.wd_we;
for (i = 0; i < n; i++) {
we->we_idle = ntohl(we->we_idle);
we->we_utmp.out_time =
ntohl(we->we_utmp.out_time);
we++;
}
}
#endif
(void) time(&t);
wd.wd_recvtime = _time_to_int(t);
(void) write(whod, (char *)&wd, cc);
if (fstat(whod, &st) < 0 || st.st_size > cc)
ftruncate(whod, cc);
(void) close(whod);
}
}
static void
usage()
{
fprintf(stderr, "usage: rwhod [-i] [-p] [-l] [-m [ttl]]\n");
exit(1);
}
void
run_as(uid, gid)
uid_t *uid;
gid_t *gid;
{
struct passwd *pw;
struct group *gr;
pw = getpwnam(UNPRIV_USER);
if (!pw) {
syslog(LOG_ERR, "getpwnam(%s): %m", UNPRIV_USER);
exit(1);
}
*uid = pw->pw_uid;
gr = getgrnam(UNPRIV_GROUP);
if (!gr) {
syslog(LOG_ERR, "getgrnam(%s): %m", UNPRIV_GROUP);
exit(1);
}
*gid = gr->gr_gid;
}
/*
* Check out host name for unprintables
* and other funnies before allowing a file
* to be created. Sorry, but blanks aren't allowed.
*/
int
verify(name, maxlen)
register char *name;
register int maxlen;
{
register int size = 0;
while (*name && size < maxlen - 1) {
if (!isascii(*name) || !(isalnum(*name) || ispunct(*name)))
return (0);
name++, size++;
}
*name = '\0';
return (size > 0);
}
void
onalrm(int signo __unused)
{
struct neighbor *np;
struct whoent *we = mywd.wd_we, *wend;
struct stat stb;
struct utmpx *ut;
static int alarmcount = 0;
double avenrun[3];
time_t now;
int i, cc;
now = time(NULL);
if (alarmcount % 10 == 0)
getboottime(0);
alarmcount++;
wend = &mywd.wd_we[1024 / sizeof(struct whoent)];
setutxent();
while ((ut = getutxent()) != NULL && we < wend) {
if (ut->ut_type != USER_PROCESS)
continue;
strncpy(we->we_utmp.out_line, ut->ut_line,
sizeof(we->we_utmp.out_line));
strncpy(we->we_utmp.out_name, ut->ut_user,
sizeof(we->we_utmp.out_name));
we->we_utmp.out_time =
htonl(_time_to_time32(ut->ut_tv.tv_sec));
we++;
}
endutxent();
if (chdir(_PATH_DEV)) {
syslog(LOG_ERR, "chdir(%s): %m", _PATH_DEV);
exit(1);
}
wend = we;
for (we = mywd.wd_we; we < wend; we++) {
if (stat(we->we_utmp.out_line, &stb) >= 0)
we->we_idle = htonl(now - stb.st_atime);
we++;
}
(void)getloadavg(avenrun, sizeof(avenrun)/sizeof(avenrun[0]));
for (i = 0; i < 3; i++)
mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100));
cc = (char *)wend - (char *)&mywd;
mywd.wd_sendtime = htonl(_time_to_time32(time(NULL)));
mywd.wd_vers = WHODVERSION;
mywd.wd_type = WHODTYPE_STATUS;
if (multicast_mode == SCOPED_MULTICAST) {
(void) sendto(s, (char *)&mywd, cc, 0,
(struct sockaddr *)&multicast_addr,
sizeof(multicast_addr));
}
else for (np = neighbors; np != NULL; np = np->n_next) {
if (multicast_mode == PER_INTERFACE_MULTICAST &&
np->n_flags & IFF_MULTICAST) {
/*
* Select the outgoing interface for the multicast.
*/
if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
&(((struct sockaddr_in *)np->n_addr)->sin_addr),
sizeof(struct in_addr)) < 0) {
syslog(LOG_ERR,
"setsockopt IP_MULTICAST_IF: %m");
exit(1);
}
(void) sendto(s, (char *)&mywd, cc, 0,
(struct sockaddr *)&multicast_addr,
sizeof(multicast_addr));
} else (void) sendto(s, (char *)&mywd, cc, 0,
np->n_addr, np->n_addrlen);
}
if (chdir(_PATH_RWHODIR)) {
syslog(LOG_ERR, "chdir(%s): %m", _PATH_RWHODIR);
exit(1);
}
(void) alarm(AL_INTERVAL);
}
void
getboottime(signo)
int signo __unused;
{
int mib[2];
size_t size;
struct timeval tm;
mib[0] = CTL_KERN;
mib[1] = KERN_BOOTTIME;
size = sizeof(tm);
if (sysctl(mib, 2, &tm, &size, NULL, 0) == -1) {
syslog(LOG_ERR, "cannot get boottime: %m");
exit(1);
}
mywd.wd_boottime = htonl(_time_to_time32(tm.tv_sec));
}
void
quit(msg)
const char *msg;
{
syslog(LOG_ERR, "%s", msg);
exit(1);
}
void
rt_xaddrs(cp, cplim, rtinfo)
register caddr_t cp, cplim;
register struct rt_addrinfo *rtinfo;
{
register struct sockaddr *sa;
register int i;
memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
if ((rtinfo->rti_addrs & (1 << i)) == 0)
continue;
rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
cp += SA_SIZE(sa);
}
}
/*
* Figure out device configuration and select
* networks which deserve status information.
*/
int
configure(so)
int so;
{
register struct neighbor *np;
register struct if_msghdr *ifm;
register struct ifa_msghdr *ifam;
struct sockaddr_dl *sdl;
size_t needed;
int mib[6], flags = 0, len;
char *buf, *lim, *next;
struct rt_addrinfo info;
if (multicast_mode != NO_MULTICAST) {
multicast_addr.sin_addr.s_addr = htonl(INADDR_WHOD_GROUP);
multicast_addr.sin_port = sp->s_port;
}
if (multicast_mode == SCOPED_MULTICAST) {
struct ip_mreq mreq;
unsigned char ttl;
mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
mreq.imr_interface.s_addr = htonl(INADDR_ANY);
if (setsockopt(so, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&mreq, sizeof(mreq)) < 0) {
syslog(LOG_ERR,
"setsockopt IP_ADD_MEMBERSHIP: %m");
return(0);
}
ttl = multicast_scope;
if (setsockopt(so, IPPROTO_IP, IP_MULTICAST_TTL,
&ttl, sizeof(ttl)) < 0) {
syslog(LOG_ERR,
"setsockopt IP_MULTICAST_TTL: %m");
return(0);
}
return(1);
}
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_INET;
mib[4] = NET_RT_IFLIST;
mib[5] = 0;
if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
quit("route-sysctl-estimate");
if ((buf = malloc(needed)) == NULL)
quit("malloc");
if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
quit("actual retrieval of interface table");
lim = buf + needed;
sdl = NULL; /* XXX just to keep gcc -Wall happy */
for (next = buf; next < lim; next += ifm->ifm_msglen) {
ifm = (struct if_msghdr *)next;
if (ifm->ifm_type == RTM_IFINFO) {
sdl = (struct sockaddr_dl *)(ifm + 1);
flags = ifm->ifm_flags;
continue;
}
if ((flags & IFF_UP) == 0 ||
(flags & (((multicast_mode == PER_INTERFACE_MULTICAST) ?
IFF_MULTICAST : 0) |
IFF_BROADCAST|iff_flag)) == 0)
continue;
if (ifm->ifm_type != RTM_NEWADDR)
quit("out of sync parsing NET_RT_IFLIST");
ifam = (struct ifa_msghdr *)ifm;
info.rti_addrs = ifam->ifam_addrs;
rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam,
&info);
/* gag, wish we could get rid of Internet dependencies */
#define dstaddr info.rti_info[RTAX_BRD]
#define ifaddr info.rti_info[RTAX_IFA]
#define IPADDR_SA(x) ((struct sockaddr_in *)(x))->sin_addr.s_addr
#define PORT_SA(x) ((struct sockaddr_in *)(x))->sin_port
if (dstaddr == 0 || dstaddr->sa_family != AF_INET)
continue;
PORT_SA(dstaddr) = sp->s_port;
for (np = neighbors; np != NULL; np = np->n_next)
if (memcmp(sdl->sdl_data, np->n_name,
sdl->sdl_nlen) == 0 &&
IPADDR_SA(np->n_addr) == IPADDR_SA(dstaddr))
break;
if (np != NULL)
continue;
len = sizeof(*np) + dstaddr->sa_len + sdl->sdl_nlen + 1;
np = (struct neighbor *)malloc(len);
if (np == NULL)
quit("malloc of neighbor structure");
memset(np, 0, len);
np->n_flags = flags;
np->n_addr = (struct sockaddr *)(np + 1);
np->n_addrlen = dstaddr->sa_len;
np->n_name = np->n_addrlen + (char *)np->n_addr;
memcpy((char *)np->n_addr, (char *)dstaddr, np->n_addrlen);
memcpy(np->n_name, sdl->sdl_data, sdl->sdl_nlen);
if (multicast_mode == PER_INTERFACE_MULTICAST &&
(flags & IFF_MULTICAST) &&
!(flags & IFF_LOOPBACK)) {
struct ip_mreq mreq;
memcpy((char *)np->n_addr, (char *)ifaddr,
np->n_addrlen);
mreq.imr_multiaddr.s_addr = htonl(INADDR_WHOD_GROUP);
mreq.imr_interface.s_addr =
((struct sockaddr_in *)np->n_addr)->sin_addr.s_addr;
if (setsockopt(s, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&mreq, sizeof(mreq)) < 0) {
syslog(LOG_ERR,
"setsockopt IP_ADD_MEMBERSHIP: %m");
#if 0
/* Fall back to broadcast on this if. */
np->n_flags &= ~IFF_MULTICAST;
#else
free((char *)np);
continue;
#endif
}
}
np->n_next = neighbors;
neighbors = np;
}
free(buf);
return (1);
}
#ifdef DEBUG
void
Sendto(s, buf, cc, flags, to, tolen)
int s;
const void *buf;
size_t cc;
int flags;
const struct sockaddr *to;
int tolen;
{
register struct whod *w = (struct whod *)buf;
register struct whoent *we;
struct sockaddr_in *sin = (struct sockaddr_in *)to;
printf("sendto %x.%d\n", ntohl(sin->sin_addr.s_addr),
ntohs(sin->sin_port));
printf("hostname %s %s\n", w->wd_hostname,
interval(ntohl(w->wd_sendtime) - ntohl(w->wd_boottime), " up"));
printf("load %4.2f, %4.2f, %4.2f\n",
ntohl(w->wd_loadav[0]) / 100.0, ntohl(w->wd_loadav[1]) / 100.0,
ntohl(w->wd_loadav[2]) / 100.0);
cc -= WHDRSIZE;
for (we = w->wd_we, cc /= sizeof(struct whoent); cc > 0; cc--, we++) {
time_t t = _time32_to_time(ntohl(we->we_utmp.out_time));
printf("%-8.8s %s:%s %.12s",
we->we_utmp.out_name,
w->wd_hostname, we->we_utmp.out_line,
ctime(&t)+4);
we->we_idle = ntohl(we->we_idle) / 60;
if (we->we_idle) {
if (we->we_idle >= 100*60)
we->we_idle = 100*60 - 1;
if (we->we_idle >= 60)
printf(" %2d", we->we_idle / 60);
else
printf(" ");
printf(":%02d", we->we_idle % 60);
}
printf("\n");
}
}
char *
interval(time, updown)
int time;
char *updown;
{
static char resbuf[32];
int days, hours, minutes;
if (time < 0 || time > 3*30*24*60*60) {
(void) sprintf(resbuf, " %s ??:??", updown);
return (resbuf);
}
minutes = (time + 59) / 60; /* round to minutes */
hours = minutes / 60; minutes %= 60;
days = hours / 24; hours %= 24;
if (days)
(void) sprintf(resbuf, "%s %2d+%02d:%02d",
updown, days, hours, minutes);
else
(void) sprintf(resbuf, "%s %2d:%02d",
updown, hours, minutes);
return (resbuf);
}
#endif