OSPFD 2.0 Bug fixes

This page briefly describes each of the bug fixes made to the OSPFD 2.0 implementation. The base 2.0 sources can be retrieved as a gzipped tar file. For each bug fix a diff file is included that can be used to update the source distribution using the patch utility. To apply a patch, change to the top-level directory of your ospfd distribution, and then type patch -Np1 < patch_file, where patch_file is one of the patches contained in this directory.

Patches must be applied in order. They were produced using diff -Nabur old_dir new_dir.

You can download the entire 2.x release in one gzipped tar file by clicking here.

OSPFD 2.0 Patch listing
  • Patch 2.1. Two separate fixes. First, we prevent forwarding addresses on directly attached but unadvertised subnets from being resolved, which allows static routes with these next hops to be installed in the kernel routing table and advertised in AS-external-LSAs with forwarding address set to 0.0.0.0. Second, we reference lsa_ifp and lsa_ap in opqlsa.C iff they are non-zero.
  • Patch 2.2. Changes in preparation for the implementation of the hitless OSPF restart scheme described in draft-ietf-ospf-hitless-restart-00.txt. (a) Added the ability to detect routing table entries left in the kernel from previous ospfd runs; these are called remnants. ospfd calls the system interface routine OspfSysCalls::upload_remnants() to request that it be notified of all remnants. Each remnant is then passed to ospfd in a call to the API routine OSPF::remnant_notification(), whereupon ospfd deletes the remnant if it is no longer valid. (b) Have the simulated ospfds keep their own copy of the routing table, where it can persist over ospfd restarts. (c) Implement a restart menu tab in the ospf simulator.
  • Patch 2.3. Since host routes are (a) advertised in other than their configured area if their configured area has no active real interfaces and (b) have been implemented as a (pseudo) interface, we have to remove an interface from all areas' interface maps when the interface is deleted.
  • Patch 2.4. An implementation of the latest OSPF Hitless Restart specification (draft-ietf-ospf-hitless-restart-01.txt). All support implemented in the common code, and a port to the OSPF simulator is also supplied. To execute a hitless restart of a simulated router, select Router->Hitless Restart and click on the desired router. After the router has prepared for hitless restart it will log a message "Hitless restart preparation complete". At that time, selecting Router->Hitless Restart and clicking on the router a second time will restart the router in hitless restart mode. When hitless restart is completed, a message "Exiting hitless restart" will be logged along with a success or failure indication. In addition, the following features were added, and bugs were fixed:
    1. The ability to display link-local Opaque-LSAs from ospfd_browser.
    2. A bug fix to the link-local Opaque-LSA handling, which would previously cause the router to crash when parsing such LSAs (opqlsa.C)
    3. Fix a crash that could occur when a down interface is advertised due to MinLSInterval (rte.C).
    4. More bug fixes involving the (re)advertising of host routes when the connections to their area go away or are restored (rte.C and rtrlsa.C).
    5. Don't send Hellos at the slower polled rate until a full window of Hellos have been sent. This fix applies to demand circuits only. (spfhello.C).
    6. Stop timers when they are destroyed (timer.C).
  • Patch 2.5. Two bug fixes related to memory allocation/deallocation.
  • Patch 2.6. Changes required to get the Linux port and simulator working under RedHat 7.1 (Linux 2.4). Also, two fixes dealing with deferred LSAs. The first fixes a problem where the router would mistakenly defer a received self-originated LSA for up to 30 minutes. The second fixes a crash when a deferred LSA still references a broadcast/NBMA network that has since been deleted from the router's configuration.
  • Patch 2.7. Three unrelated bug fixes: a) Interfaces can now be identified in the ospfd config file by name (e.g., "eth0", "tunl1", etc.) instead of IP address. This allows configuration of unnumbered interfaces, including IP-in-IP tunnels, b) Fix OSPF::deferred_lsas() and OSPF::schedule_refresh() so that LSA reorigination will never corrupt the age bins (Exercise 6.2), and c) Fix the cost reported for routing table entries in the ospfd monitor interface.
  • Patch 2.8. Completed coding that allows the MOSPF implementation to use the Linux kernel mrouted support, thereby turning a Linux machine into a MOSPF router. The mrouted support is not quite enough to implement a full MOSPF router though. In particular, you don't get support for a) NBMA interfaces, b) unnumbered interfaces, or c) multiple point-to-point links between a single pair of MOSPF routers. However, if you are just using LAN interfaces and IPIP tunnels, everything should work fine. One note on supporting IPIP tunnels: ospfd doesn't create them. You have to create them manually using /sbin/iptunnel, and admin them up using /sbin/ifconfig. Then they can be referred to be name (e.g., "tunl1") in the ospfd configuration file.
  • Patch 2.9. Two patches to MOSPF. The first fixes a crash that occurred when an IGMP message was received on a non-MOSPF interface. The second allows the MOSPF router to monitor IGMP membership on all MOSPF interfaces, instead of the previous behavior which monitored group membership only on broadcast subnets. If you want to monitor group membership but you don't want OSPF packets exchanged on an interface, configured the interface as passive.
  • Patch 2.10. Fix to the Linux routing table interface. Must set TOS to 0 in netlink messages, or else kernels with TOS enabled (CONFIG_IP_ROUTE_TOS) will install multiple routing table entries with random TOS assignments. Thanks to Elwyn Davies for pointing this out.
  • Patch 2.11. More MOSPF patches. Allow IGMP to be run over interfaces other than broadcast interfaces. However, in order to enable IGMP on these other interface types in the Linux port, must include the igmp interface command for each interface in /etc/ospfd.conf. Also, the following MOSPF fixes, courtesy of Marc Castejon: (a) Join 224.0.0.2, so that we can receive IGMP leave messages, (b) Fix Last Member Query processing and (c) ignore MaxAge group-membership-LSAs in multicast path calculation.
  • Patch 2.12. Two unrelated changes. The first is to the logic which keeps the ospfd routing tabl;e in synch with the Linux kernel's forwarding table. When the last address is deleted from an interface, the Linux kernel silently deletes all forwarding entries going over the interface. The Linux port of ospfd has now been changed so that deletion of the last address is treated as an interface down event, which causes ospfd to also delete the forwarding entries. The second change affects the advertisement of point-to-point links. We key on the interface mask configured for the link. If the mask is 0 or all ones, we advertise the neighbor's IP address (the previous behavior). Otherwise, we advertise a stub link for the entire subnet. In addition, the code will now advertise subnets for tunnels, whereas before tunnels were always treated as unnumbered links.
  • Patch 2.13. When deleting an area or interface, must make sure that the associated LSAs are deleted also, but you don't have to reflood them. Previously they could hang around if you weren't allowed to garbage collect the MaxAge LSAs (for example, one ore more neighbors were in Database Exchange state), causing the router to crash.
  • Patch 2.14. Implementation of the changes in the latest version of the OSPF Hitless Restart draft (draft-ietf-ospf-hitless-restart-02.txt)..
  • Patch 2.15. Two unrelated bug fixes. First, reparse any remaining network-LSAs whose Link State ID match the LSA being deleted, as described on page 91 of OSPF Complete Implementation -- this was one of those rare occasions where the documentation was mor up-to-date than the code. Second, make routers with DR priority of 0 respond to the first Hello from a DR-eligible router, otherwise these adjacencies would never come up. Added the drpri configuration command to the simulator so that you can now test differing DR priorities.
  • Patch 2.16. Bug fixes to the NBMA/Point-to-MultiPoint Hello logic. Code now sends Hellos at the correct rate depending on neighbor state. Previously, would not send hellos to NBMA neighbor that transitioned to Down state (should send at the reduced rate of PollInterval).