4.3BSD - /usr/src/etc/XNSrouted/output.c

   1: /*
   2:  * Copyright (c) 1985 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  *
   6:  * Includes material written at Cornell University by Bill Nesheim,
   7:  * by permission of the author.
   8:  */
   9: 
  10: #ifndef lint
  11: static char sccsid[] = "@(#)output.c	5.5 (Berkeley) 2/14/86";
  12: #endif
  13: 
  14: /*
  15:  * Routing Table Management Daemon
  16:  */
  17: #include "defs.h"
  18: 
  19: /*
  20:  * Apply the function "f" to all non-passive
  21:  * interfaces.  If the interface supports the
  22:  * use of broadcasting use it, otherwise address
  23:  * the output to the known router.
  24:  */
  25: toall(f)
  26:     int (*f)();
  27: {
  28:     register struct interface *ifp;
  29:     register struct sockaddr *dst;
  30:     register int flags;
  31:     extern struct interface *ifnet;
  32: 
  33:     for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  34:         if (ifp->int_flags & IFF_PASSIVE)
  35:             continue;
  36:         dst = ifp->int_flags & IFF_BROADCAST ? &ifp->int_broadaddr :
  37:               ifp->int_flags & IFF_POINTOPOINT ? &ifp->int_dstaddr :
  38:               &ifp->int_addr;
  39:         flags = ifp->int_flags & IFF_INTERFACE ? MSG_DONTROUTE : 0;
  40:         (*f)(dst, flags, ifp);
  41:     }
  42: }
  43: 
  44: /*
  45:  * Output a preformed packet.
  46:  */
  47: /*ARGSUSED*/
  48: sendmsg(dst, flags, ifp)
  49:     struct sockaddr *dst;
  50:     int flags;
  51:     struct interface *ifp;
  52: {
  53: 
  54:     (*afswitch[dst->sa_family].af_output)
  55:         (flags, dst, sizeof (struct rip));
  56:     TRACE_OUTPUT(ifp, dst, sizeof (struct rip));
  57: }
  58: 
  59: /*
  60:  * Supply dst with the contents of the routing tables.
  61:  * If this won't fit in one packet, chop it up into several.
  62:  */
  63: supply(dst, flags, ifp)
  64:     struct sockaddr *dst;
  65:     int flags;
  66:     struct interface *ifp;
  67: {
  68:     register struct rt_entry *rt;
  69:     register struct rthash *rh;
  70:     register struct netinfo *nn;
  71:     register struct netinfo *n = msg->rip_nets;
  72:     struct rthash *base = hosthash;
  73:     struct sockaddr_ns *sns =  (struct sockaddr_ns *) dst;
  74:     int (*output)() = afswitch[dst->sa_family].af_output;
  75:     int doinghost = 1, size, metric;
  76:     union ns_net net;
  77: 
  78:     msg->rip_cmd = ntohs(RIPCMD_RESPONSE);
  79: again:
  80:     for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++)
  81:     for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
  82:         size = (char *)n - (char *)msg;
  83:         if (size > MAXPACKETSIZE - sizeof (struct netinfo)) {
  84:             (*output)(flags, dst, size);
  85:             TRACE_OUTPUT(ifp, dst, size);
  86:             n = msg->rip_nets;
  87:         }
  88:         sns = (struct sockaddr_ns *)&rt->rt_dst;
  89:             if ((rt->rt_flags & (RTF_HOST|RTF_GATEWAY)) == RTF_HOST)
  90:             sns = (struct sockaddr_ns *)&rt->rt_router;
  91:         metric = min(rt->rt_metric + 1, HOPCNT_INFINITY);
  92:         net = sns->sns_addr.x_net;
  93:         /*
  94: 		 * Make sure that we don't put out a two net entries
  95: 		 * for a pt to pt link (one for the G route, one for the if)
  96: 		 * This is a kludge, and won't work if there are lots of nets.
  97: 		 */
  98:         for (nn = msg->rip_nets; nn < n; nn++) {
  99:             if (ns_neteqnn(net, nn->rip_dst)) {
 100:                 if (metric < ntohs(nn->rip_metric))
 101:                     nn->rip_metric = htons(metric);
 102:                 goto next;
 103:             }
 104:         }
 105:         n->rip_dst = net;
 106:         n->rip_metric = htons(metric);
 107:         n++;
 108:     next:;
 109:     }
 110:     if (doinghost) {
 111:         doinghost = 0;
 112:         base = nethash;
 113:         goto again;
 114:     }
 115:     if (n != msg->rip_nets) {
 116:         size = (char *)n - (char *)msg;
 117:         (*output)(flags, dst, size);
 118:         TRACE_OUTPUT(ifp, dst, size);
 119:     }
 120: }

Defined functions

Defined variables