zebra: add connected_check_ptp infrastructure

add a connected_check_ptp function which does the same as
connected_check, but takes an additional peer prefix argument.

also fix related prefixlen mixup in PtP addresses (the local part of a
PtP address always is /32, but previously the peer mask got copied.)

3 files changed, 51 insertions, 7 deletions

diff --git a/zebra/connected.c b/zebra/connected.c
index 95399fa1..bf5715e4 100644
--- a/zebra/connected.c
+++ b/zebra/connected.c
@@ -112,6 +112,30 @@ connected_check (struct interface *ifp, struct prefix *p)
   return NULL;
 }
 
+/* same, but with peer address */
+struct connected *
+connected_check_ptp (struct interface *ifp, struct prefix *p, struct prefix *d)
+{
+  struct connected *ifc;
+  struct listnode *node;
+
+  /* ignore broadcast addresses */
+  if (p->prefixlen != IPV4_MAX_PREFIXLEN)
+    d = NULL;
+
+  for (ALL_LIST_ELEMENTS_RO (ifp->connected, node, ifc))
+    {
+      if (!prefix_same (ifc->address, p))
+	continue;
+      if (!CONNECTED_PEER(ifc) && !d)
+	return ifc;
+      if (CONNECTED_PEER(ifc) && d && prefix_same (ifc->destination, d))
+	return ifc;
+    }
+
+  return NULL;
+}
+
 /* Check if two ifc's describe the same address */
 static int
 connected_same (struct connected *ifc1, struct connected *ifc2)
@@ -148,7 +172,7 @@ connected_implicit_withdraw (struct interface *ifp, struct connected *ifc)
   struct connected *current;
   
   /* Check same connected route. */
-  if ((current = connected_check (ifp, (struct prefix *) ifc->address)))
+  if ((current = connected_check_ptp (ifp, ifc->address, ifc->destination)))
     {
       if (CHECK_FLAG(current->conf, ZEBRA_IFC_CONFIGURED))
         SET_FLAG(ifc->conf, ZEBRA_IFC_CONFIGURED);
@@ -212,7 +236,8 @@ connected_add_ipv4 (struct interface *ifp, int flags, struct in_addr *addr,
   p = prefix_ipv4_new ();
   p->family = AF_INET;
   p->prefix = *addr;
-  p->prefixlen = prefixlen;
+  p->prefixlen = CHECK_FLAG(flags, ZEBRA_IFA_PEER)
+		 ? IPV4_MAX_PREFIXLEN : prefixlen;
   ifc->address = (struct prefix *) p;
   
   /* If there is broadcast or peer address. */
@@ -305,15 +330,27 @@ void
 connected_delete_ipv4 (struct interface *ifp, int flags, struct in_addr *addr,
 		       u_char prefixlen, struct in_addr *broad)
 {
-  struct prefix_ipv4 p;
+  struct prefix_ipv4 p, d;
   struct connected *ifc;
 
   memset (&p, 0, sizeof (struct prefix_ipv4));
   p.family = AF_INET;
   p.prefix = *addr;
-  p.prefixlen = prefixlen;
+  p.prefixlen = CHECK_FLAG(flags, ZEBRA_IFA_PEER)
+		? IPV4_MAX_PREFIXLEN : prefixlen;
+
+  if (broad)
+    {
+      memset (&d, 0, sizeof (struct prefix_ipv4));
+      d.family = AF_INET;
+      d.prefix = *broad;
+      d.prefixlen = prefixlen;
+      ifc = connected_check_ptp (ifp, (struct prefix *) &p,
+				 (struct prefix *) &d);
+    }
+  else
+    ifc = connected_check_ptp (ifp, (struct prefix *) &p, NULL);
 
-  ifc = connected_check (ifp, (struct prefix *) &p);
   if (! ifc)
     return;
     
diff --git a/zebra/connected.h b/zebra/connected.h
index 9595ddb1..0f7c586b 100644
--- a/zebra/connected.h
+++ b/zebra/connected.h
@@ -25,6 +25,8 @@
 
 extern struct connected *
 connected_check (struct interface *ifp, struct prefix *p);
+extern struct connected *
+connected_check_ptp (struct interface *ifp, struct prefix *p, struct prefix *d);
 
 extern void
 connected_add_ipv4 (struct interface *ifp, int flags, struct in_addr *addr, 
diff --git a/zebra/interface.c b/zebra/interface.c
index aa078925..7c2fbe9c 100644
--- a/zebra/interface.c
+++ b/zebra/interface.c
@@ -127,7 +127,7 @@ if_subnet_add (struct interface *ifp, struct connected *ifc)
 
   /* Get address derived subnet node and associated address list, while marking
      address secondary attribute appropriately. */
-  cp = *ifc->address;
+  cp = *CONNECTED_PREFIX(ifc);
   apply_mask (&cp);
   rn = route_node_get (zebra_if->ipv4_subnets, &cp);
 
@@ -154,12 +154,16 @@ if_subnet_delete (struct interface *ifp, struct connected *ifc)
   struct route_node *rn;
   struct zebra_if *zebra_if;
   struct list *addr_list;
+  struct prefix cp;
 
   assert (ifp && ifp->info && ifc);
   zebra_if = ifp->info;
 
+  cp = *CONNECTED_PREFIX(ifc);
+  apply_mask (&cp);
+
   /* Get address derived subnet node. */
-  rn = route_node_lookup (zebra_if->ipv4_subnets, ifc->address);
+  rn = route_node_lookup (zebra_if->ipv4_subnets, &cp);
   if (! (rn && rn->info))
     return -1;
   route_unlock_node (rn);
@@ -588,6 +592,7 @@ connected_dump_vty (struct vty *vty, struct connected *connected)
     {
       vty_out (vty, (CONNECTED_PEER(connected) ? " peer " : " broadcast "));
       prefix_vty_out (vty, connected->destination);
+      vty_out (vty, "/%d", connected->destination->prefixlen);
     }
 
   if (CHECK_FLAG (connected->flags, ZEBRA_IFA_SECONDARY))