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

   1: /*
   2:  * Copyright (c) 1983 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: 
   7: #ifndef lint
   8: static char sccsid[] = "@(#)output.c	5.3 (Berkeley) 5/30/86";
   9: #endif not lint
  10: 
  11: /*
  12:  * Routing Table Management Daemon
  13:  */
  14: #include "defs.h"
  15: 
  16: /*
  17:  * Apply the function "f" to all non-passive
  18:  * interfaces.  If the interface supports the
  19:  * use of broadcasting use it, otherwise address
  20:  * the output to the known router.
  21:  */
  22: toall(f)
  23:     int (*f)();
  24: {
  25:     register struct interface *ifp;
  26:     register struct sockaddr *dst;
  27:     register int flags;
  28:     extern struct interface *ifnet;
  29: 
  30:     for (ifp = ifnet; ifp; ifp = ifp->int_next) {
  31:         if (ifp->int_flags & IFF_PASSIVE)
  32:             continue;
  33:         dst = ifp->int_flags & IFF_BROADCAST ? &ifp->int_broadaddr :
  34:               ifp->int_flags & IFF_POINTOPOINT ? &ifp->int_dstaddr :
  35:               &ifp->int_addr;
  36:         flags = ifp->int_flags & IFF_INTERFACE ? MSG_DONTROUTE : 0;
  37:         (*f)(dst, flags, ifp);
  38:     }
  39: }
  40: 
  41: /*
  42:  * Output a preformed packet.
  43:  */
  44: /*ARGSUSED*/
  45: sendmsg(dst, flags, ifp)
  46:     struct sockaddr *dst;
  47:     int flags;
  48:     struct interface *ifp;
  49: {
  50: 
  51:     (*afswitch[dst->sa_family].af_output)(s, flags,
  52:         dst, sizeof (struct rip));
  53:     TRACE_OUTPUT(ifp, dst, sizeof (struct rip));
  54: }
  55: 
  56: /*
  57:  * Supply dst with the contents of the routing tables.
  58:  * If this won't fit in one packet, chop it up into several.
  59:  */
  60: supply(dst, flags, ifp)
  61:     struct sockaddr *dst;
  62:     int flags;
  63:     struct interface *ifp;
  64: {
  65:     register struct rt_entry *rt;
  66:     struct netinfo *n = msg->rip_nets;
  67:     register struct rthash *rh;
  68:     struct rthash *base = hosthash;
  69:     int doinghost = 1, size;
  70:     int (*output)() = afswitch[dst->sa_family].af_output;
  71:     int (*sendsubnet)() = afswitch[dst->sa_family].af_sendsubnet;
  72: 
  73:     msg->rip_cmd = RIPCMD_RESPONSE;
  74:     msg->rip_vers = RIPVERSION;
  75: again:
  76:     for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++)
  77:     for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
  78:         /*
  79: 		 * Don't resend the information
  80: 		 * on the network from which it was received.
  81: 		 */
  82:         if (ifp && rt->rt_ifp == ifp)
  83:             continue;
  84:         if (rt->rt_state & RTS_EXTERNAL)
  85:             continue;
  86:         /*
  87: 		 * Limit the spread of subnet information
  88: 		 * to those who are interested.
  89: 		 */
  90:         if (doinghost == 0 && rt->rt_state & RTS_SUBNET) {
  91:             if (ifp && (ifp->int_flags & IFF_SUBNET) == 0)
  92:                 continue;
  93:             if (rt->rt_dst.sa_family != dst->sa_family)
  94:                 continue;
  95:             if ((*sendsubnet)(rt, dst) == 0)
  96:                 continue;
  97:         }
  98:         size = (char *)n - packet;
  99:         if (size > MAXPACKETSIZE - sizeof (struct netinfo)) {
 100:             (*output)(s, flags, dst, size);
 101:             TRACE_OUTPUT(ifp, dst, size);
 102:             n = msg->rip_nets;
 103:         }
 104:         n->rip_dst = rt->rt_dst;
 105:         n->rip_dst.sa_family = htons(n->rip_dst.sa_family);
 106:         n->rip_metric = htonl(min(rt->rt_metric + 1, HOPCNT_INFINITY));
 107:         n++;
 108:     }
 109:     if (doinghost) {
 110:         doinghost = 0;
 111:         base = nethash;
 112:         goto again;
 113:     }
 114:     if (n != msg->rip_nets) {
 115:         size = (char *)n - packet;
 116:         (*output)(s, flags, dst, size);
 117:         TRACE_OUTPUT(ifp, dst, size);
 118:     }
 119: }

Defined functions

Defined variables