2005-04-02 Andrew J. Schorr <ajschorr@alumni.princeton.edu>

	Fix problems when netlink interfaces are renamed (same ifindex used
	for a new interface).  Start cleaning up some problems with the way
	interface names are handled.
	* interface.c: (if_new_intern_ifindex) Remove obsolete function.
	  (if_delete_update) After distributing the interface deletion message,
	  set ifp->ifindex to IFINDEX_INTERNAL.
	  (if_dump_vty) Detect pseudo interface by checking if ifp->ifindex is
	  IFINDEX_INTERNAL.
	  (zebra_interface) Check return code from interface_cmd.func.
	  Do not set internal ifindex values to if_new_intern_ifindex(),
	  since we now use IFINDEX_INTERNAL for all pseudo interfaces.
	* kernel_socket.c: (ifm_read) Fix code and comments to reflect that
	  all internal interfaces now have ifp->ifindex set to IFINDEX_INTERNAL.
        * rt_netlink.c: (set_ifindex) New function used to update ifp->ifindex.
	  Detects interface rename events by checking if that ifindex is already
	  being used.  If it is, delete the old interface before assigning
	  the ifindex to the new interface.
	  (netlink_interface, netlink_link_change) Call set_ifindex to update
	  the ifindex.
	* if.h: Remove define for IFINDEX_INTERNBASE and add define
	  IFINDEX_INTERNAL 0, since all internal (i.e. non-kernel) pseudo-
	  interfaces should have ifindex set to 0.
	  (if_new) Remove function.
	  (if_delete_retain) New function to delete an interface without
	  removing from iflist and freeing the structure.
	  (ifname2ifindex) New function.
	* if.c: (if_new) Remove function (absorb into if_create).
	  (if_create) Replace function if_new with call to calloc.
	  Set ifp->ifindex to IFINDEX_INTERNAL.  Fix off-by-one error
	  in assert to check length of interface name.  Add error message
	  if interface with this name already exists.
	  (if_delete_retain) New function to delete an interface without
	  removing from iflist and freeing the structure.
	  (if_delete) Implement with help of if_delete_retain.
	  (ifindex2ifname) Reimplement using if_lookup_by_index.
	  (ifname2ifindex) New function to complement ifindex2ifname.
	  (interface) The interface command should check the name length
	  and fail with a warning message if it is too long.
	  (no_interface) Fix spelling in warning message.
	  (if_nametoindex) Reimplement using if_lookup_by_name.
	  (if_indextoname, ifaddr_ipv4_lookup) Reimplement using
	  if_lookup_by_index.
	* bgp_zebra.c: (bgp_interface_delete) After deleting, set ifp->ifindex
	  to IFINDEX_INTERNAL.
	* isis_zebra.c: (isis_zebra_if_del) Call if_delete_retain instead
	  of if_delete, since it is generally not safe to remove interface
	  structures.  After deleting, set ifp->ifindex to IFINDEX_INTERNAL.
	  (zebra_interface_if_lookup) Tighten up code.
	* ospf6_zebra.c: (ospf6_zebra_if_del) Previously, this whole function
	  was commented out.  But this is not safe: we should at least update
	  the ifindex when the interface is deleted.  So the new version
	  updates the interface status and sets ifp->ifindex to
	  IFINDEX_INTERNAL.
	  (ospf6_zebra_route_update) Use if_indextoname properly.
	* ospf_vty.c: (show_ip_ospf_interface_sub) Show ifindex and interface
	  flags to help with debugging.
	* ospf_zebra.c: (ospf_interface_delete) After deleting, set ifp->ifindex
	  to IFINDEX_INTERNAL.
	  (zebra_interface_if_lookup) Make function static.  Tighten up code.
	* rip_interface.c: (rip_interface_delete) After deleting, set
	  ifp->ifindex to IFINDEX_INTERNAL.
	* ripng_interface.c: (ripng_interface_delete) After deleting, set
	  ifp->ifindex to IFINDEX_INTERNAL.

1 files changed, 5 insertions, 9 deletions

diff --git a/zebra/kernel_socket.c b/zebra/kernel_socket.c
index e6e74449..cdc6822c 100644
--- a/zebra/kernel_socket.c
+++ b/zebra/kernel_socket.c
@@ -301,8 +301,8 @@ ifm_read (struct if_msghdr *ifm)
    * If lookup by index was unsuccessful and we have a name, try
    * looking up by name.  Interfaces specified in the configuration
    * file for which the ifindex has not been determined will have
-   * ifindex == -1, and such interfaces are found by this search, and
-   * then their ifindex values can be filled in.
+   * ifindex == IFINDEX_INTERNAL, and such interfaces are found by this search,
+   * and then their ifindex values can be filled in.
    */
   if (ifp == NULL && sdl != NULL)
     {
@@ -322,14 +322,10 @@ ifm_read (struct if_msghdr *ifm)
     }
 
   /*
-   * If ifp does not exist or has an invalid index (-1), create or
+   * If ifp does not exist or has an invalid index (IFINDEX_INTERNAL), create or
    * fill in an interface.
    */
-  /*
-   * XXX warning: comparison between signed and unsigned
-   * ifindex should probably be signed
-   */
-  if ((ifp == NULL) || (ifp->ifindex == -1))
+  if ((ifp == NULL) || (ifp->ifindex == IFINDEX_INTERNAL))
     {
       /*
        * To create or fill in an interface, a sockaddr_dl (via
@@ -348,7 +344,7 @@ ifm_read (struct if_msghdr *ifm)
 
       /* 
        * Fill in newly created interface structure, or larval
-       * structure with ifindex -1.
+       * structure with ifindex IFINDEX_INTERNAL.
        */
       ifp->ifindex = ifm->ifm_index;
       ifp->flags = ifm->ifm_flags;