bfd: Implement forwarding_if_rx.

This commit adds a new boolean option "forwarding_if_rx" to bfd.

When forwarding_if_rx is true the interface will be considered
capable of packet I/O as long as there is packet received at
interface.  This is important in that when link becomes temporarily
conjested, consecutive BFD control packets can be lost.  And the
forwarding_if_rx can prevent link failover by detecting non-control
packets received at interface.

Signed-off-by: Alex Wang <alexw@nicira.com>

1 files changed, 252 insertions, 2 deletions

diff --git a/tests/bfd.at b/tests/bfd.at
index da45b27e1..0b2b7ccf4 100644
--- a/tests/bfd.at
+++ b/tests/bfd.at
@@ -261,14 +261,14 @@ OVS_VSWITCHD_START([add-br br1 -- set bridge br1 datapath-type=dummy -- \
 ovs-appctl time/stop
 
 # wait for local session state to go from down to up.
-for i in `seq 0 2`; do ovs-appctl time/warp 500; done
+for i in `seq 0 1`; do ovs-appctl time/warp 500; done
 BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [init], [No Diagnostic])
 
 
 # Test-1 BFD decay: decay to decay_min_rx
 # bfd:decay_min_rx is set to 3000ms after the local state of p0 goes up,
 # so for the first 2500ms, there should be no change.
-for i in `seq 0 3`; do ovs-appctl time/warp 500; done
+for i in `seq 0 4`; do ovs-appctl time/warp 500; done
 BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
 BFD_CHECK_TX([p0], [500ms], [300ms], [500ms])
 BFD_CHECK_RX([p0], [500ms], [300ms], [500ms])
@@ -507,4 +507,254 @@ BFD_CHECK_RX([p0], [3000ms], [3000ms], [500ms])
 # End of Test-8 ################################################################
 
 OVS_VSWITCHD_STOP
+AT_CLEANUP
+
+# Tests below are for bfd forwarding_if_rx feature.
+# forwarding_if_rx Test1: bfd is enabled on one end of link.
+AT_SETUP([bfd - bfd forwarding_if_rx 1])
+OVS_VSWITCHD_START([add-br br1 -- set bridge br1 datapath-type=dummy -- \
+                    add-port br1 p1 -- set Interface p1 type=patch \
+                    options:peer=p0 ofport_request=2 -- \
+                    add-port br0 p0 -- set Interface p0 type=patch \
+                    options:peer=p1 ofport_request=1 -- \
+                    set Interface p0 bfd:enable=true bfd:min_tx=500 bfd:min_rx=500 -- \
+                    add-port br1 p2 -- set Interface p2 type=internal ofport_request=3])
+
+ovs-appctl time/stop
+# check the inital status.
+BFD_CHECK([p0], [false], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+
+# enable forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=true], [0])
+
+# there should be no change of forwarding flag, since
+# there is no traffic.
+for i in `seq 0 3`
+do
+    ovs-appctl time/warp 500
+    BFD_CHECK([p0], [false], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+done
+
+# receive one packet.
+AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+             [0], [stdout], [])
+for i in `seq 0 14`
+do
+    ovs-appctl time/warp 100
+    # the forwarding flag should be true, since there is data received.
+    BFD_CHECK([p0], [true], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+    BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+    BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+done
+
+# Stop sending packets for 1000ms.
+for i in `seq 0 9`; do ovs-appctl time/warp 100; done
+BFD_CHECK([p0], [false], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+
+# receive packet at 1/100ms rate for 1000ms.
+for i in `seq 0 9`
+do
+    ovs-appctl time/warp 100
+    AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+             [0], [stdout], [])
+done
+# the forwarding flag should be true, since there is data received.
+BFD_CHECK([p0], [true], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+
+# reset bfd forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=false], [0])
+# forwarding flag should turn to false since the STATE is DOWN.
+BFD_CHECK([p0], [false], [false], [none], [down], [No Diagnostic], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+
+AT_CHECK([ovs-vsctl del-br br1], [0], [ignore])
+AT_CLEANUP
+
+# forwarding_if_rx Test2: bfd is enabled on both ends of link.
+AT_SETUP([bfd - bfd forwarding_if_rx 2])
+OVS_VSWITCHD_START([add-br br1 -- set bridge br1 datapath-type=dummy -- \
+                    add-port br1 p1 -- set Interface p1 type=patch \
+                    options:peer=p0 ofport_request=2 -- \
+                    add-port br0 p0 -- set Interface p0 type=patch \
+                    options:peer=p1 ofport_request=1 -- \
+                    set Interface p0 bfd:enable=true bfd:min_tx=500 bfd:min_rx=500 -- \
+                    set Interface p1 bfd:enable=true bfd:min_tx=300 bfd:min_rx=300 -- \
+                    add-port br1 p2 -- set Interface p2 type=internal ofport_request=3])
+
+ovs-appctl time/stop
+# advance the clock, to stablize the states.
+for i in `seq 0 9`; do ovs-appctl time/warp 500; done
+
+# enable forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=true], [0])
+
+# there should be no change of the forwarding flag, since
+# the bfd on both ends is already up.
+for i in `seq 0 5`
+do
+    ovs-appctl time/warp 500
+    BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+done
+
+# stop the bfd on one side.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=false], [0])
+# for within 1500ms, the detection timer is not out.
+# there is no change to status.
+for i in `seq 0 1`
+do
+    ovs-appctl time/warp 500
+    BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+    for i in `seq 0 5`
+    do
+        AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+                 [0], [stdout], [])
+    done
+done
+
+# at 1500ms, the STATE should go DOWN, due to Control Detection Time Expired.
+# but forwarding flag should be still true.
+ovs-appctl time/warp 500
+BFD_CHECK([p0], [true], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+
+# receive packet at 1/100ms rate for 1000ms.
+for i in `seq 0 9`
+do
+    AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+             [0], [stdout], [])
+    ovs-appctl time/warp 100
+    # the forwarding flag should always be true during this time.
+    BFD_CHECK([p0], [true], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+done
+
+# reset bfd forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=false], [0])
+# forwarding flag should turn to false since the STATE is DOWN.
+BFD_CHECK([p0], [false], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [1ms])
+
+# re-enable bfd on the other end. the states should be up.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=true bfd:min_tx=300 bfd:min_rx=300])
+# advance the clock, to stablize the states.
+for i in `seq 0 9`; do ovs-appctl time/warp 500; done
+BFD_CHECK([p0], [true], [false], [none], [up], [Control Detection Time Expired], [none], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [none], [up], [Control Detection Time Expired])
+BFD_CHECK_TX([p0], [500ms], [500ms], [300ms])
+BFD_CHECK_RX([p0], [500ms], [500ms], [300ms])
+
+AT_CHECK([ovs-vsctl del-br br1], [0], [ignore])
+AT_CLEANUP
+
+# forwarding_if_rx Test3: bfd is enabled on both ends of link and decay is enabled.
+AT_SETUP([bfd - bfd forwarding_if_rx 3])
+OVS_VSWITCHD_START([add-br br1 -- set bridge br1 datapath-type=dummy -- \
+                    add-port br1 p1 -- set Interface p1 type=patch \
+                    options:peer=p0 ofport_request=2 -- \
+                    add-port br0 p0 -- set Interface p0 type=patch \
+                    options:peer=p1 ofport_request=1 -- \
+                    set Interface p0 bfd:enable=true bfd:min_tx=300 bfd:min_rx=300 bfd:decay_min_rx=3000 -- \
+                    set Interface p1 bfd:enable=true bfd:min_tx=500 bfd:min_rx=500])
+
+ovs-appctl time/stop
+# advance the clock, to stablize the states.
+for i in `seq 0 19`; do ovs-appctl time/warp 500; done
+BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+BFD_CHECK_TX([p0], [500ms], [300ms], [500ms])
+BFD_CHECK_RX([p0], [3000ms], [3000ms], [500ms])
+
+# enable forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=true], [0])
+
+# there should be no change of the forwarding flag, since
+# the bfd on both ends is already up.
+for i in `seq 0 9`
+do
+    ovs-appctl time/warp 500
+    BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+done
+
+# reconfigure the decay_min_rx to 1000ms. check the poll sequence.
+AT_CHECK([ovs-vsctl set interface p0 bfd:decay_min_rx=1000])
+BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [final], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [poll], [up], [No Diagnostic])
+BFD_CHECK_TX([p0], [500ms], [300ms], [500ms])
+BFD_CHECK_RX([p0], [500ms], [300ms], [500ms])
+
+# wait for 2000ms to decay.
+for i in `seq 0 3`; do ovs-appctl time/warp 500; done
+BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [final], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [poll], [up], [No Diagnostic])
+BFD_CHECK_TX([p0], [500ms], [300ms], [500ms])
+BFD_CHECK_RX([p0], [1000ms], [1000ms], [500ms])
+
+# wait for 1000ms, so that the flags will go back to none.
+for i in `seq 0 1`; do ovs-appctl time/warp 500; done
+BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+BFD_CHECK_TX([p0], [500ms], [300ms], [500ms])
+BFD_CHECK_RX([p0], [1000ms], [1000ms], [500ms])
+
+# stop the bfd on one side.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=false], [0])
+# for within 2500ms, the detection timer is not out.
+# there is no change to status.
+for i in `seq 0 4`
+do
+    ovs-appctl time/warp 500
+    BFD_CHECK([p0], [true], [false], [none], [up], [No Diagnostic], [none], [up], [No Diagnostic])
+    AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+             [0], [stdout], [])
+done
+
+# at 3000ms, the STATE should go DOWN, due to Control Detection Time Expired.
+# but forwarding flag should be still true.
+ovs-appctl time/warp 500
+BFD_CHECK([p0], [true], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+
+# receive packet at 1/100ms rate for 1000ms.
+for i in `seq 0 9`
+do
+    AT_CHECK([ovs-ofctl packet-out br1 3 2  "90e2ba01475000101856b2e80806000108000604000100101856b2e80202020300000000000002020202"],
+             [0], [stdout], [])
+    ovs-appctl time/warp 100
+    # the forwarding flag should always be true during this time.
+    BFD_CHECK([p0], [true], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+done
+
+# stop receiving for 2000ms.
+for i in `seq 0 19`; do ovs-appctl time/warp 100; done
+BFD_CHECK([p0], [false], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+
+# reset bfd forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=false])
+# forwarding flag should turn to false since the STATE is DOWN.
+BFD_CHECK([p0], [false], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [300ms], [300ms], [1ms])
+
+# re-enable bfd forwarding_if_rx.
+AT_CHECK([ovs-vsctl set Interface p0 bfd:forwarding_if_rx=true])
+# there should be no change.
+BFD_CHECK([p0], [false], [false], [none], [down], [Control Detection Time Expired], [none], [down], [No Diagnostic])
+BFD_CHECK_TX([p0], [1000ms], [1000ms], [0ms])
+BFD_CHECK_RX([p0], [300ms], [300ms], [1ms])
+
+# re-enable bfd on the other end. the states should be up.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=true bfd:min_tx=300 bfd:min_rx=300])
+# advance the clock, to stablize the states.
+for i in `seq 0 9`; do ovs-appctl time/warp 500; done
+BFD_CHECK([p0], [true], [false], [none], [up], [Control Detection Time Expired], [none], [up], [No Diagnostic])
+BFD_CHECK([p1], [true], [false], [none], [up], [No Diagnostic], [none], [up], [Control Detection Time Expired])
+BFD_CHECK_TX([p0], [300ms], [300ms], [300ms])
+BFD_CHECK_RX([p0], [1000ms], [1000ms], [300ms])
+
+AT_CHECK([ovs-vsctl del-br br1], [0], [ignore])
 AT_CLEANUP
\ No newline at end of file