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|
--- lib/if.c.orig Fri Jun 21 23:49:50 2002
+++ lib/if.c Mon Oct 14 17:25:42 2002
@@ -553,6 +553,65 @@
return NULL;
}
+/* Find the IPv4 address on our side that will be used when packets
+ are sent to dst. */
+struct connected *
+connected_lookup_address (struct interface *ifp, struct in_addr dst)
+{
+ struct prefix addr;
+ struct prefix best;
+ listnode cnode;
+ struct prefix *p;
+ struct connected *c;
+ struct connected *match;
+
+ /* Zero structures - get rid of rubbish from stack */
+ memset(&addr, 0, sizeof(addr));
+ memset(&best, 0, sizeof(best));
+
+ addr.family = AF_INET;
+ addr.u.prefix4 = dst;
+ addr.prefixlen = IPV4_MAX_BITLEN;
+
+ match = NULL;
+
+ for (cnode = listhead (ifp->connected); cnode; nextnode (cnode))
+ {
+ c = getdata (cnode);
+
+ if (if_is_pointopoint (ifp))
+ {
+ p = c->address;
+
+ if (p && p->family == AF_INET)
+ {
+#ifdef OLD_RIB /* PTP links are conventionally identified
+ by the address of the far end - MAG */
+ if (IPV4_ADDR_SAME (&p->u.prefix4, &dst))
+ return c;
+#endif
+ p = c->destination;
+ if (p && IPV4_ADDR_SAME (&p->u.prefix4, &dst))
+ return c;
+ }
+ }
+ else
+ {
+ p = c->address;
+
+ if (p->family == AF_INET)
+ {
+ if (prefix_match (p, &addr) && p->prefixlen > best.prefixlen)
+ {
+ best = *p;
+ match = c;
+ }
+ }
+ }
+ }
+ return match;
+}
+
/* Check the connected information is PtP style or not. */
int
ifc_pointopoint (struct connected *ifc)
--- ./lib/if.h.orig Fri Jun 21 23:49:50 2002
+++ ./lib/if.h Mon Oct 14 17:25:42 2002
@@ -202,6 +202,7 @@
void connected_free (struct connected *);
void connected_add (struct interface *, struct connected *);
struct connected *connected_delete_by_prefix (struct interface *, struct prefix *);
+struct connected *connected_lookup_address (struct interface *, struct in_addr);
int ifc_pointopoint (struct connected *);
#ifndef HAVE_IF_NAMETOINDEX
--- ./ripd/ripd.c.orig Mon Jul 1 02:57:22 2002
+++ ./ripd/ripd.c Tue Oct 15 10:02:11 2002
@@ -55,8 +55,8 @@
/* Prototypes. */
void rip_event (enum rip_event, int);
-void rip_output_process (struct interface *, struct sockaddr_in *,
- int, u_char);
+void rip_output_process (struct interface *, struct prefix *,
+ struct sockaddr_in *, int, u_char);
/* RIP output routes type. */
enum
@@ -955,7 +955,14 @@
{
caddr_t lim;
struct rte *rte;
+ struct prefix_ipv4 ifaddr;
+ struct prefix_ipv4 ifaddrclass;
+ struct connected *c;
+ int subnetted;
+ /* We don't know yet. */
+ subnetted = -1;
+
/* The Response must be ignored if it is not from the RIP
port. (RFC2453 - Sec. 3.9.2)*/
if (ntohs (from->sin_port) != RIP_PORT_DEFAULT)
@@ -1108,23 +1115,51 @@
{
u_int32_t destination;
- destination = ntohl (rte->prefix.s_addr);
-
- if (destination & 0xff)
+ if (subnetted == -1)
{
- masklen2ip (32, &rte->mask);
+ c = connected_lookup_address (ifp, from->sin_addr);
+ if (c != NULL)
+ {
+ memcpy (&ifaddr, c->address, sizeof (struct prefix_ipv4));
+ memcpy (&ifaddrclass, &ifaddr, sizeof (struct prefix_ipv4));
+ apply_classful_mask_ipv4 (&ifaddrclass);
+ subnetted = 0;
+ if (ifaddr.prefixlen > ifaddrclass.prefixlen)
+ subnetted = 1;
+ }
}
- else if ((destination & 0xff00) || IN_CLASSC (destination))
- {
+
+ destination = ntohl (rte->prefix.s_addr);
+
+ if (IN_CLASSA (destination))
+ masklen2ip (8, &rte->mask);
+ else if (IN_CLASSB (destination))
+ masklen2ip (16, &rte->mask);
+ else if (IN_CLASSC (destination))
masklen2ip (24, &rte->mask);
+
+ if (subnetted == 1)
+ masklen2ip (ifaddrclass.prefixlen,
+ (struct in_addr *) &destination);
+ if ((subnetted == 1) && ((rte->prefix.s_addr & destination) ==
+ ifaddrclass.prefix.s_addr))
+ {
+ masklen2ip (ifaddr.prefixlen, &rte->mask);
+ if ((rte->prefix.s_addr & rte->mask.s_addr) != rte->prefix.s_addr)
+ masklen2ip (32, &rte->mask);
+ if (IS_RIP_DEBUG_EVENT)
+ zlog_info ("Subnetted route %s", inet_ntoa (rte->prefix));
}
- else if ((destination & 0xff0000) || IN_CLASSB (destination))
+ else
{
- masklen2ip (16, &rte->mask);
+ if ((rte->prefix.s_addr & rte->mask.s_addr) != rte->prefix.s_addr)
+ continue;
}
- else
+
+ if (IS_RIP_DEBUG_EVENT)
{
- masklen2ip (8, &rte->mask);
+ zlog_info ("Resultant route %s", inet_ntoa (rte->prefix));
+ zlog_info ("Resultant mask %s", inet_ntoa (rte->mask));
}
}
@@ -1353,7 +1388,7 @@
ntohl (rte->metric) == RIP_METRIC_INFINITY)
{
/* All route with split horizon */
- rip_output_process (ifp, from, rip_all_route, packet->version);
+ rip_output_process (ifp, NULL, from, rip_all_route, packet->version);
}
else
{
@@ -1884,8 +1919,8 @@
/* Send update to the ifp or spcified neighbor. */
void
-rip_output_process (struct interface *ifp, struct sockaddr_in *to,
- int route_type, u_char version)
+rip_output_process (struct interface *ifp, struct prefix *ifaddr,
+ struct sockaddr_in *to, int route_type, u_char version)
{
int ret;
struct stream *s;
@@ -1894,8 +1929,11 @@
struct rip_interface *ri;
struct prefix_ipv4 *p;
struct prefix_ipv4 classfull;
+ struct prefix_ipv4 ifaddrclass;
+ struct connected *c;
int num;
int rtemax;
+ int subnetted;
/* Logging output event. */
if (IS_RIP_DEBUG_EVENT)
@@ -1946,29 +1984,60 @@
rtemax -=1;
}
+ if (version == RIPv1)
+ {
+ if (ifaddr == NULL)
+ {
+ c = connected_lookup_address (ifp, to->sin_addr);
+ if (c != NULL)
+ ifaddr = c->address;
+ }
+ if (ifaddr == NULL)
+ {
+ zlog_warn ("cannot find source address for packets to neighbor %s",
+ inet_ntoa (to->sin_addr));
+ return;
+ }
+ memcpy (&ifaddrclass, ifaddr, sizeof (struct prefix_ipv4));
+ apply_classful_mask_ipv4 (&ifaddrclass);
+ subnetted = 0;
+ if (ifaddr->prefixlen > ifaddrclass.prefixlen)
+ subnetted = 1;
+ }
+
for (rp = route_top (rip->table); rp; rp = route_next (rp))
if ((rinfo = rp->info) != NULL)
{
- /* Some inheritance stuff: */
- /* Before we process with ipv4 prefix we should mask it */
- /* with Classful mask if we send RIPv1 packet.That's because */
- /* user could set non-classful mask or we could get it by RIPv2 */
- /* or other protocol. checked with Cisco's way of life :) */
+ /* For RIPv1, if we are subnetted, output subnets in our network */
+ /* that have the same mask as the output "interface". For other */
+ /* networks, only the classfull version is output. */
if (version == RIPv1)
{
- memcpy (&classfull, &rp->p, sizeof (struct prefix_ipv4));
+ p = (struct prefix_ipv4 *) &rp->p;
if (IS_RIP_DEBUG_PACKET)
- zlog_info("%s/%d before RIPv1 mask check ",
- inet_ntoa (classfull.prefix), classfull.prefixlen);
-
- apply_classful_mask_ipv4 (&classfull);
- p = &classfull;
+ zlog_info("RIPv1 mask check, %s/%d considered for output",
+ inet_ntoa (rp->p.u.prefix4), rp->p.prefixlen);
+ if (subnetted &&
+ prefix_match ((struct prefix *) &ifaddrclass, &rp->p))
+ {
+ if ((ifaddr->prefixlen != rp->p.prefixlen) &&
+ (rp->p.prefixlen != 32))
+ continue;
+ }
+ else
+ {
+ memcpy (&classfull, &rp->p, sizeof(struct prefix_ipv4));
+ apply_classful_mask_ipv4(&classfull);
+ if (rp->p.u.prefix4.s_addr != 0 &&
+ classfull.prefixlen != rp->p.prefixlen)
+ continue;
+ }
if (IS_RIP_DEBUG_PACKET)
- zlog_info("%s/%d after RIPv1 mask check",
- inet_ntoa (p->prefix), p->prefixlen);
+ zlog_info("RIPv1 mask check, %s/%d made it through",
+ inet_ntoa (rp->p.u.prefix4), rp->p.prefixlen);
}
else
p = (struct prefix_ipv4 *) &rp->p;
@@ -2109,7 +2178,7 @@
if (IS_RIP_DEBUG_EVENT)
zlog_info ("multicast announce on %s ", ifp->name);
- rip_output_process (ifp, NULL, route_type, version);
+ rip_output_process (ifp, NULL, NULL, route_type, version);
return;
}
@@ -2136,7 +2205,8 @@
if_is_pointopoint (ifp) ? "unicast" : "broadcast",
inet_ntoa (to.sin_addr), ifp->name);
- rip_output_process (ifp, &to, route_type, version);
+ rip_output_process (ifp, connected->address, &to, route_type,
+ version);
}
}
}
@@ -2224,7 +2294,7 @@
to.sin_port = htons (RIP_PORT_DEFAULT);
/* RIP version is rip's configuration. */
- rip_output_process (ifp, &to, route_type, rip->version);
+ rip_output_process (ifp, NULL, &to, route_type, rip->version);
}
}
|
