zebra: NetBSD: get IPSRCSEL preference value from kernel

fetch the address preference value from the kernel through
SIOCGIFADDRPREF and pass it to quagga through connected_add_ipv4,
which stores it in struct connected->preference.

IPSRCSEL is a NetBSD kernel option(4), documented in in_getifa(9) and
is available since NetBSD 4.0 but not enabled in default GENERIC.

8 files changed, 36 insertions, 8 deletions

diff --git a/zebra/connected.c b/zebra/connected.c
index 82c531e4..0c22582d 100644
--- a/zebra/connected.c
+++ b/zebra/connected.c
@@ -269,7 +269,7 @@ connected_up_ipv4 (struct interface *ifp, struct connected *ifc)
 void
 connected_add_ipv4 (struct interface *ifp, int flags, struct in_addr *addr, 
 		    u_char prefixlen, struct in_addr *broad, 
-		    const char *label, unsigned scope)
+		    const char *label, unsigned scope, int preference)
 {
   struct prefix_ipv4 *p;
   struct connected *ifc;
@@ -342,6 +342,7 @@ connected_add_ipv4 (struct interface *ifp, int flags, struct in_addr *addr,
     ifc->label = XSTRDUP (MTYPE_CONNECTED_LABEL, label);
 
   ifc->scope = scope;
+  ifc->preference = preference;
 
   /* nothing to do? */
   if ((ifc = connected_implicit_withdraw (ifp, ifc)) == NULL)
diff --git a/zebra/connected.h b/zebra/connected.h
index 5ea6d54d..ede75120 100644
--- a/zebra/connected.h
+++ b/zebra/connected.h
@@ -31,7 +31,7 @@ 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, 
 		    u_char prefixlen, struct in_addr *broad, 
-		    const char *label, unsigned scope);
+		    const char *label, unsigned scope, int preference);
 
 extern void
 connected_delete_ipv4 (struct interface *ifp, int flags, struct in_addr *addr,
diff --git a/zebra/if_ioctl.c b/zebra/if_ioctl.c
index e85c744c..36732704 100644
--- a/zebra/if_ioctl.c
+++ b/zebra/if_ioctl.c
@@ -276,7 +276,7 @@ if_getaddrs (void)
 	    }
 
 	  connected_add_ipv4 (ifp, flags, &addr->sin_addr,
-			      prefixlen, dest_pnt, NULL, 0);
+			      prefixlen, dest_pnt, NULL, 0, 0);
 	}
 #ifdef HAVE_IPV6
       if (ifap->ifa_addr->sa_family == AF_INET6)
@@ -412,7 +412,7 @@ if_get_addr (struct interface *ifp)
 
 
   /* Set address to the interface. */
-  connected_add_ipv4 (ifp, flags, &addr.sin_addr, prefixlen, dest_pnt, NULL, 0);
+  connected_add_ipv4 (ifp, flags, &addr.sin_addr, prefixlen, dest_pnt, NULL, 0, 0);
 
   return 0;
 }
diff --git a/zebra/if_ioctl_solaris.c b/zebra/if_ioctl_solaris.c
index 86fcc484..736232e8 100644
--- a/zebra/if_ioctl_solaris.c
+++ b/zebra/if_ioctl_solaris.c
@@ -327,7 +327,7 @@ if_get_addr (struct interface *ifp, struct sockaddr *addr, const char *label)
   /* Set address to the interface. */
   if (af == AF_INET)
     connected_add_ipv4 (ifp, flags, &SIN (addr)->sin_addr, prefixlen,
-                        (struct in_addr *) dest_pnt, label, 0);
+                        (struct in_addr *) dest_pnt, label, 0, 0);
 #ifdef HAVE_IPV6
   else if (af == AF_INET6)
     connected_add_ipv6 (ifp, flags, &SIN6 (addr)->sin6_addr, prefixlen,
diff --git a/zebra/interface.c b/zebra/interface.c
index 11c99f73..590a177d 100644
--- a/zebra/interface.c
+++ b/zebra/interface.c
@@ -599,6 +599,10 @@ connected_dump_vty (struct vty *vty, struct connected *connected)
   if (connected->scope != 0)
     vty_out (vty, " scope %s", connected_scope_name (connected->scope));
 #endif
+#ifdef SIOCSIFADDRPREF
+  if (connected->preference != 0)
+    vty_out (vty, " preference %d", connected->preference);
+#endif
 
   if (CHECK_FLAG (connected->flags, ZEBRA_IFA_SECONDARY))
     vty_out (vty, " secondary");
diff --git a/zebra/kernel_null.c b/zebra/kernel_null.c
index fa90b99b..f83c2345 100644
--- a/zebra/kernel_null.c
+++ b/zebra/kernel_null.c
@@ -25,7 +25,7 @@ int kernel_address_add_ipv4 (struct interface *a, struct connected *b)
   SET_FLAG (b->conf, ZEBRA_IFC_REAL);
   connected_add_ipv4 (a, 0, &b->address->u.prefix4, b->address->prefixlen, 
                       (b->destination ? &b->destination->u.prefix4 : NULL), 
-                      NULL, 0);
+                      NULL, 0, 0);
   return 0;
 }
 
diff --git a/zebra/kernel_socket.c b/zebra/kernel_socket.c
index 5a0359ea..aa962a35 100644
--- a/zebra/kernel_socket.c
+++ b/zebra/kernel_socket.c
@@ -253,6 +253,25 @@ rtm_flag_dump (int flag)
   zlog_debug ("Kernel: %s", buf);
 }
 
+/* NetBSD IPSRCSEL preference readback */
+static int
+if_get_addrpref (const char *ifname, struct sockaddr_in *addr)
+{
+#ifdef SIOCSIFADDRPREF
+  int ret;
+  struct if_addrprefreq ifapr;
+
+  memset (&ifapr, 0, sizeof ifapr);
+  strncpy ((char *)&ifapr.ifap_name, ifname, sizeof ifapr.ifap_name);
+  memcpy (&ifapr.ifap_addr, addr, sizeof (struct sockaddr_in));
+
+  ret = if_ioctl (SIOCGIFADDRPREF, (caddr_t) &ifapr);
+  if (ret == 0)
+    return ifapr.ifap_preference;
+#endif
+  return 0;
+}
+
 #ifdef RTM_IFANNOUNCE
 /* Interface adding function */
 static int
@@ -619,6 +638,7 @@ ifam_read (struct ifa_msghdr *ifam)
   short ifnlen = 0;
   char isalias = 0;
   int flags = 0;
+  int preference = 0;
   
   ifname[0] = ifname[INTERFACE_NAMSIZ - 1] = '\0';
   
@@ -649,6 +669,9 @@ ifam_read (struct ifa_msghdr *ifam)
    */
   ifp->metric = ifam->ifam_metric;
 #endif
+  if (sockunion_family (&addr) == AF_INET
+      && ifam->ifam_type == RTM_NEWADDR)
+    preference = if_get_addrpref (ifp->name, &addr.sin);
 
   /* Add connected address. */
   switch (sockunion_family (&addr))
@@ -658,7 +681,7 @@ ifam_read (struct ifa_msghdr *ifam)
 	connected_add_ipv4 (ifp, flags, &addr.sin.sin_addr, 
 			    ip_masklen (mask.sin.sin_addr),
 			    &brd.sin.sin_addr,
-			    (isalias ? ifname : NULL), 0);
+			    (isalias ? ifname : NULL), 0, preference);
       else
 	connected_delete_ipv4 (ifp, flags, &addr.sin.sin_addr, 
 			       ip_masklen (mask.sin.sin_addr),
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index 92ce8d69..d25543ff 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -617,7 +617,7 @@ netlink_interface_addr (struct sockaddr_nl *snl, struct nlmsghdr *h)
       if (h->nlmsg_type == RTM_NEWADDR)
         connected_add_ipv4 (ifp, flags,
                             (struct in_addr *) addr, ifa->ifa_prefixlen,
-                            (struct in_addr *) broad, label, ifa->ifa_scope);
+                            (struct in_addr *) broad, label, ifa->ifa_scope, 0);
       else
         connected_delete_ipv4 (ifp, flags,
                                (struct in_addr *) addr, ifa->ifa_prefixlen,