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.
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index 042ee33..b3b2aab 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -86,6 +86,33 @@
extern u_int32_t nl_rcvbufsize;
+/* Note: on netlink systems, there should be a 1-to-1 mapping between interface
+ names and ifindex values. */
+static void
+set_ifindex(struct interface *ifp, unsigned int ifi_index)
+{
+ struct interface *oifp;
+
+ if (((oifp = if_lookup_by_index(ifi_index)) != NULL) && (oifp != ifp))
+ {
+ if (ifi_index == IFINDEX_INTERNAL)
+ zlog_err("Netlink is setting interface %s ifindex to reserved "
+ "internal value %u", ifp->name, ifi_index);
+ else
+ {
+ if (IS_ZEBRA_DEBUG_KERNEL)
+ zlog_debug("interface index %d was renamed from %s to %s",
+ ifi_index, oifp->name, ifp->name);
+ if (if_is_up(oifp))
+ zlog_err("interface rename detected on up interface: index %d "
+ "was renamed from %s to %s, results are uncertain!",
+ ifi_index, oifp->name, ifp->name);
+ if_delete_update(oifp);
+ }
+ }
+ ifp->ifindex = ifi_index;
+}
+
/* Make socket for Linux netlink interface. */
static int
netlink_socket (struct nlsock *nl, unsigned long groups)
@@ -504,8 +531,7 @@
/* Add interface. */
ifp = if_get_by_name (name);
-
- ifp->ifindex = ifi->ifi_index;
+ set_ifindex(ifp, ifi->ifi_index);
ifp->flags = ifi->ifi_flags & 0x0000fffff;
ifp->mtu6 = ifp->mtu = *(int *) RTA_DATA (tb[IFLA_MTU]);
ifp->metric = 1;
@@ -981,7 +1007,7 @@
if (ifp == NULL)
ifp = if_get_by_name (name);
- ifp->ifindex = ifi->ifi_index;
+ set_ifindex(ifp, ifi->ifi_index);
ifp->flags = ifi->ifi_flags & 0x0000fffff;
ifp->mtu6 = ifp->mtu = *(int *) RTA_DATA (tb[IFLA_MTU]);
ifp->metric = 1;
@@ -992,7 +1018,7 @@
else
{
/* Interface status change. */
- ifp->ifindex = ifi->ifi_index;
+ set_ifindex(ifp, ifi->ifi_index);
ifp->mtu6 = ifp->mtu = *(int *) RTA_DATA (tb[IFLA_MTU]);
ifp->metric = 1;