4.2BSD/usr/src/etc/rwhod/rwhod.c
#ifndef lint
static char sccsid[] = "@(#)rwhod.c 4.19 (Berkeley) 83/07/01";
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <net/if.h>
#include <netinet/in.h>
#include <nlist.h>
#include <stdio.h>
#include <signal.h>
#include <errno.h>
#include <utmp.h>
#include <ctype.h>
#include <netdb.h>
#include "rwhod.h"
struct sockaddr_in sin = { AF_INET };
extern errno;
char myname[32];
struct nlist nl[] = {
#define NL_AVENRUN 0
{ "_avenrun" },
#define NL_BOOTTIME 1
{ "_boottime" },
0
};
/*
* 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 */
char *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, utmpf, kmemf = -1;
#define WHDRSIZE (sizeof (mywd) - sizeof (mywd.wd_we))
#define RWHODIR "/usr/spool/rwho"
int onalrm();
char *strcpy(), *sprintf(), *malloc();
long lseek();
int getkmem();
struct in_addr inet_makeaddr();
main()
{
struct sockaddr_in from;
char path[64];
int addr;
struct hostent *hp;
sp = getservbyname("who", "udp");
if (sp == 0) {
fprintf(stderr, "rwhod: udp/who: unknown service\n");
exit(1);
}
#ifndef DEBUG
if (fork())
exit(0);
{ int s;
for (s = 0; s < 10; s++)
(void) close(s);
(void) open("/", 0);
(void) dup2(0, 1);
(void) dup2(0, 2);
s = open("/dev/tty", 2);
if (s >= 0) {
ioctl(s, TIOCNOTTY, 0);
(void) close(s);
}
}
#endif
(void) chdir("/dev");
(void) signal(SIGHUP, getkmem);
if (getuid()) {
fprintf(stderr, "rwhod: not super user\n");
exit(1);
}
/*
* Establish host name as returned by system.
*/
if (gethostname(myname, sizeof (myname) - 1) < 0) {
perror("gethostname");
exit(1);
}
strncpy(mywd.wd_hostname, myname, sizeof (myname) - 1);
utmpf = open("/etc/utmp", O_RDONLY);
if (utmpf < 0) {
(void) close(creat("/etc/utmp", 0644));
utmpf = open("/etc/utmp", O_RDONLY);
}
if (utmpf < 0) {
perror("rwhod: /etc/utmp");
exit(1);
}
getkmem();
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
perror("rwhod: socket");
exit(1);
}
hp = gethostbyname(myname);
if (hp == NULL) {
fprintf(stderr, "%s: don't know my own name\n", myname);
exit(1);
}
sin.sin_family = hp->h_addrtype;
sin.sin_port = sp->s_port;
if (bind(s, &sin, sizeof (sin)) < 0) {
perror("rwhod: bind");
exit(1);
}
if (!configure(s))
exit(1);
signal(SIGALRM, onalrm);
onalrm();
for (;;) {
struct whod wd;
int cc, whod, len = sizeof (from);
cc = recvfrom(s, (char *)&wd, sizeof (struct whod), 0,
&from, &len);
if (cc <= 0) {
if (cc < 0 && errno != EINTR)
perror("rwhod: recv");
continue;
}
if (from.sin_port != sp->s_port) {
fprintf(stderr, "rwhod: %d: bad from port\n",
ntohs(from.sin_port));
continue;
}
#ifdef notdef
if (gethostbyname(wd.wd_hostname) == 0) {
fprintf(stderr, "rwhod: %s: unknown host\n",
wd.wd_hostname);
continue;
}
#endif
if (wd.wd_vers != WHODVERSION)
continue;
if (wd.wd_type != WHODTYPE_STATUS)
continue;
if (!verify(wd.wd_hostname)) {
fprintf(stderr, "rwhod: malformed host name from %x\n",
from.sin_addr);
continue;
}
(void) sprintf(path, "%s/whod.%s", RWHODIR, wd.wd_hostname);
whod = creat(path, 0666);
if (whod < 0) {
fprintf(stderr, "rwhod: ");
perror(path);
continue;
}
#if vax || pdp11
{
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(&wd.wd_recvtime);
(void) write(whod, (char *)&wd, cc);
(void) close(whod);
}
}
/*
* Check out host name for unprintables
* and other funnies before allowing a file
* to be created. Sorry, but blanks aren't allowed.
*/
verify(name)
register char *name;
{
register int size = 0;
while (*name) {
if (!isascii(*name) || !isalnum(*name))
return (0);
name++, size++;
}
return (size > 0);
}
int utmptime;
int utmpent;
struct utmp utmp[100];
int alarmcount;
onalrm()
{
register int i;
struct stat stb;
register struct whoent *we = mywd.wd_we, *wlast;
int cc;
double avenrun[3];
time_t now = time(0);
register struct neighbor *np;
if (alarmcount % 10 == 0)
getkmem();
alarmcount++;
(void) fstat(utmpf, &stb);
if (stb.st_mtime != utmptime) {
(void) lseek(utmpf, (long)0, L_SET);
cc = read(utmpf, (char *)utmp, sizeof (utmp));
if (cc < 0) {
perror("/etc/utmp");
goto done;
}
wlast = &mywd.wd_we[1024 / sizeof (struct whoent) - 1];
utmpent = cc / sizeof (struct utmp);
for (i = 0; i < utmpent; i++)
if (utmp[i].ut_name[0]) {
bcopy(utmp[i].ut_line, we->we_utmp.out_line,
sizeof (utmp[i].ut_line));
bcopy(utmp[i].ut_name, we->we_utmp.out_name,
sizeof (utmp[i].ut_name));
we->we_utmp.out_time = htonl(utmp[i].ut_time);
if (we >= wlast)
break;
we++;
}
utmpent = we - mywd.wd_we;
}
we = mywd.wd_we;
for (i = 0; i < utmpent; i++) {
if (stat(we->we_utmp.out_line, &stb) >= 0)
we->we_idle = htonl(now - stb.st_atime);
we++;
}
(void) lseek(kmemf, (long)nl[NL_AVENRUN].n_value, L_SET);
(void) read(kmemf, (char *)avenrun, sizeof (avenrun));
for (i = 0; i < 3; i++)
mywd.wd_loadav[i] = htonl((u_long)(avenrun[i] * 100));
cc = (char *)we - (char *)&mywd;
mywd.wd_sendtime = htonl(time(0));
mywd.wd_vers = WHODVERSION;
mywd.wd_type = WHODTYPE_STATUS;
for (np = neighbors; np != NULL; np = np->n_next)
(void) sendto(s, (char *)&mywd, cc, 0,
np->n_addr, np->n_addrlen);
done:
(void) alarm(60);
}
getkmem()
{
struct nlist *nlp;
if (kmemf >= 0)
(void) close(kmemf);
loop:
for (nlp = &nl[sizeof (nl) / sizeof (nl[0])]; --nlp >= nl; ) {
nlp->n_value = 0;
nlp->n_type = 0;
}
nlist("/vmunix", nl);
if (nl[0].n_value == 0) {
fprintf(stderr, "/vmunix namelist botch\n");
sleep(300);
goto loop;
}
kmemf = open("/dev/kmem", O_RDONLY);
if (kmemf < 0) {
perror("/dev/kmem");
sleep(300);
goto loop;
}
(void) lseek(kmemf, (long)nl[NL_BOOTTIME].n_value, L_SET);
(void) read(kmemf, (char *)&mywd.wd_boottime,
sizeof (mywd.wd_boottime));
mywd.wd_boottime = htonl(mywd.wd_boottime);
}
/*
* Figure out device configuration and select
* networks which deserve status information.
*/
configure(s)
int s;
{
char buf[BUFSIZ];
struct ifconf ifc;
struct ifreq ifreq, *ifr;
struct sockaddr_in *sin;
register struct neighbor *np;
int n;
ifc.ifc_len = sizeof (buf);
ifc.ifc_buf = buf;
if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
perror("rwhod: ioctl (get interface configuration)");
return (0);
}
ifr = ifc.ifc_req;
for (n = ifc.ifc_len / sizeof (struct ifreq); n > 0; n--, ifr++) {
for (np = neighbors; np != NULL; np = np->n_next)
if (np->n_name &&
strcmp(ifr->ifr_name, np->n_name) == 0)
break;
if (np != NULL)
continue;
ifreq = *ifr;
np = (struct neighbor *)malloc(sizeof (*np));
if (np == NULL)
continue;
np->n_name = malloc(strlen(ifr->ifr_name) + 1);
if (np->n_name == NULL) {
free((char *)np);
continue;
}
strcpy(np->n_name, ifr->ifr_name);
np->n_addrlen = sizeof (ifr->ifr_addr);
np->n_addr = malloc(np->n_addrlen);
if (np->n_addr == NULL) {
free(np->n_name);
free((char *)np);
continue;
}
bcopy((char *)&ifr->ifr_addr, np->n_addr, np->n_addrlen);
if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
perror("rwhod: ioctl (get interface flags)");
free((char *)np);
continue;
}
if ((ifreq.ifr_flags & (IFF_BROADCAST|IFF_POINTOPOINT)) == 0) {
free((char *)np);
continue;
}
np->n_flags = ifreq.ifr_flags;
if (np->n_flags & IFF_POINTOPOINT) {
if (ioctl(s, SIOCGIFDSTADDR, (char *)&ifreq) < 0) {
perror("rwhod: ioctl (get dstaddr)");
free((char *)np);
continue;
}
/* we assume addresses are all the same size */
bcopy((char *)&ifreq.ifr_dstaddr,
np->n_addr, np->n_addrlen);
}
if (np->n_flags & IFF_BROADCAST) {
/* we assume addresses are all the same size */
sin = (struct sockaddr_in *)np->n_addr;
sin->sin_addr =
inet_makeaddr(inet_netof(sin->sin_addr), INADDR_ANY);
}
/* gag, wish we could get rid of Internet dependencies */
sin = (struct sockaddr_in *)np->n_addr;
sin->sin_port = sp->s_port;
np->n_next = neighbors;
neighbors = np;
}
return (1);
}
#ifdef DEBUG
sendto(s, buf, cc, flags, to, tolen)
int s;
char *buf;
int cc, flags;
char *to;
int tolen;
{
register struct whod *w = (struct whod *)buf;
register struct whoent *we;
struct sockaddr_in *sin = (struct sockaddr_in *)to;
char *interval();
printf("sendto %x.%d\n", ntohl(sin->sin_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 = 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