date and time created 85/08/16 20:22:41 by sklower

[unix-history] / usr / src / sbin / XNSrouted / main.c

#ifndef lint
static char rcsid[] = "$Header$";
#endif

/*
* XNS Routing Information Protocol Daemon
*/
#include "defs.h"
#include <sys/ioctl.h>
#include <sys/time.h>

#include <net/if.h>

#include <errno.h>
#include <nlist.h>
#include <signal.h>

int     supplier = -1;          /* process should supply updates */
extern int gateway;

struct  rip *msg = (struct rip *) &packet[sizeof (struct idp)]; 
int     hup(), fkexit();

main(argc, argv)
       int argc;
       char *argv[];
{
       struct sockaddr from;
       u_char retry;
       int selectbits;
       struct interface *ifp;
       extern struct interface *ifnet;
       
       argv0 = argv;
       argv++, argc--;
       while (argc > 0 && **argv == '-') {
               if (strcmp(*argv, "-s") == 0) {
                       supplier = 1;
                       argv++, argc--;
                       continue;
               }
               if (strcmp(*argv, "-q") == 0) {
                       supplier = 0;
                       argv++, argc--;
                       continue;
               }
               if (strcmp(*argv, "-t") == 0) {
                       tracepackets++;
                       argv++, argc--;
                       ftrace = stderr;
                       tracing = 1; 
                       continue;
               }
               if (strcmp(*argv, "-g") == 0) {
                       gateway = 1;
                       argv++, argc--;
                       continue;
               }
               if (strcmp(*argv, "-l") == 0) {
                       gateway = -1;
                       argv++, argc--;
                       continue;
               }
               fprintf(stderr,
                       "usage: xnsrouted [ -s ] [ -q ] [ -t ] [ -g ] [ -l ]\n");
               exit(1);
       }
       
#ifndef DEBUG
       if (!tracepackets) {
               int t;

               if (fork())
                       exit(0);
               for (t = 0; t < 20; t++)
                       (void) close(t);
               (void) open("/", 0);
               (void) dup2(0, 1);
               (void) dup2(0, 2);
               t = open("/dev/tty", 2);
               if (t >= 0) {
                       ioctl(t, TIOCNOTTY, (char *)0);
                       (void) close(t);
               }
       }
#endif
       /*
        * Any extra argument is considered
        * a tracing log file.
        */
       if (argc > 0)
               traceon(*argv);
       /*
        * Collect an initial view of the world by
        * snooping in the kernel.  Then, send a request packet on all
        * directly connected networks to find out what
        * everyone else thinks.
        */
       rtinit();
       ifinit();
       if (supplier < 0)
               supplier = 0;
       /* request the state of the world */
       msg->rip_cmd = htons(RIPCMD_REQUEST);
       xnnet(msg->rip_nets[0].rip_dst) = htonl(DSTNETS_ALL);
       msg->rip_nets[0].rip_metric =  htons(HOPCNT_INFINITY);
       toall(sendmsg);
       signal(SIGALRM, timer);
       signal(SIGHUP, hup);
       signal(SIGINT, hup);
       signal(SIGEMT, fkexit);
       timer();
       
       /*
        * Listen for RIF packets on all interfaces
        */
       selectbits = 0;
       for( ifp = ifnet; ifp!=0; ifp = ifp->int_next) {
               selectbits |= 1 << ifp->int_ripsock[0];
               selectbits |= 1 << ifp->int_ripsock[1];
       }

       for (;;) {
               int ibits;
               register int n;

               ibits = selectbits;
               n = select(20, &ibits, 0, 0, 0);
               if (n < 0) {
                       if(errno != EINTR) {
                               perror("main:select");
                               exit(1);
                       }
                       continue;
               }
               for( ifp = ifnet; ifp!=0; ifp = ifp->int_next) {
                   /* take RIF packet off interface */
                   for(n = 0; n < 2; n++)
                       if(ibits & (1 << ifp->int_ripsock[n]))
                               process(ifp->int_ripsock[n]);
               }
       }
}

process(fd)
       int fd;
{
       struct sockaddr from;
       int fromlen = sizeof (from), cc, omask;
       struct idp *idp = (struct idp *)packet;

       cc = recvfrom(fd, packet, sizeof (packet), 0, &from, &fromlen);
       if (cc <= 0) {
               if (cc < 0 && errno != EINTR)
                       perror("recvfrom");
               return;
       }
       /* We get the IDP header in front of the RIF packet*/
       if (tracepackets > 1) {
           fprintf(ftrace,"rcv %d bytes on %s ",
               cc, xns_ntoa(&idp->idp_dst));
           fprintf(ftrace," from %s\n", xns_ntoa(&idp->idp_src));
       }
       
       if (xnnet(idp->idp_src.xn_net) != xnnet(idp->idp_dst.xn_net)) {
               fprintf(ftrace, "XNSrouted: net of interface (%d) != net on ether (%d)!\n",
                       ntohl(xnnet(idp->idp_dst.xn_net)),
                       ntohs(xnnet(idp->idp_src.xn_net)));
       }
                       
       cc -= sizeof (struct idp);
       if (fromlen != sizeof (struct sockaddr_xn))
               return;
#define mask(s) (1<<((s)-1))
       omask = sigblock(mask(SIGALRM));
       rip_input(&from, cc);
       sigsetmask(omask);
}

getsocket(domain, type, proto, sxn)
       int domain, type, proto;
       struct sockaddr_xn *sxn;
{
       int retry, s;

       retry = 1;
       while ((s = socket(domain, type, proto, 0)) < 0 && retry) {
               perror("socket");
               sleep(5 * retry);
               retry <<= 1;
       }
       if (retry == 0)
               return (-1);
       while (bind(s, sxn, sizeof (*sxn), 0) < 0 && retry) {
               perror("bind");
               sleep(5 * retry);
               retry <<= 1;
       }
       if (retry == 0)
               return (-1);
       return (s);
}

/*
* Fork and exit on EMT-- for profiling.
*/
fkexit()
{
       if (fork() == 0)
               exit(0);
}