Optional intermediary bridge netdev

weave

@@ -293,6 +293,9 @@ PROCFS=${PROCFS:-/proc}
 DOCKER_BRIDGE=${DOCKER_BRIDGE:-docker0}
 CONTAINER_NAME=${WEAVE_CONTAINER_NAME:-weave}
 BRIDGE=weave
+FASTDP_BRIDGE=fdp-bridge
+BRIDGE_IFNAME=${BRIDGE}-link
+FASTDP_BRIDGE_IFNAME=${FASTDP_BRIDGE}-link
 CONTAINER_IFNAME=ethwe
 # ROUTER_HOSTNETNS_IFNAME is only used for fastdp with encryption
 ROUTER_HOSTNETNS_IFNAME=veth-weave
@@ -404,7 +407,13 @@ create_bridge() {
         if [ -n "$WEAVE_NO_FASTDP" ] ; then
             BRIDGE_TYPE=bridge
         elif docker run --rm --privileged --net=host $IMAGE $COVERAGE_ARGS --create-datapath --datapath=$BRIDGE ; then
-            BRIDGE_TYPE=fastdp
+            # This is not meant to be exercised by users; to be
+            # replaced by autodetection as part of #1681.
+            if [ -n "$WEAVE_NO_BRIDGED_FASTDP" ]; then
+                BRIDGE_TYPE=fastdp
+            else
+                BRIDGE_TYPE=bridged_fastdp
+            fi
         elif [ $? = 17 ] ; then
             # Exit status of 17 means the kernel doesn't have ODP
             BRIDGE_TYPE=bridge
@@ -449,7 +458,11 @@ EOF
                 return 1
             fi
         else
-            BRIDGE_TYPE=fastdp
+            if [ -d /sys/class/net/$FASTDP_BRIDGE ] ; then
+               BRIDGE_TYPE=bridged_fastdp
+            else
+               BRIDGE_TYPE=fastdp
+            fi
 
             if [ -n "$WEAVE_NO_FASTDP" ] ; then
                 cat <<EOF >&1
@@ -490,6 +503,39 @@ init_bridge_fastdp() {
     ip link set dev $BRIDGE mtu $MTU
 }
 
+init_bridge_bridged_fastdp() {
+    # Initialise the datapath as normal. NB sets MTU for use below
+    init_bridge_fastdp
+
+    # Create linking veth pair
+    ip link del $FASTDP_BRIDGE_IFNAME >/dev/null 2>&1 || true
+    ip link del $BRIDGE_IFNAME >/dev/null 2>&1 || true
+    ip link add name $FASTDP_BRIDGE_IFNAME mtu $MTU type veth peer name $BRIDGE_IFNAME mtu $MTU || return 1
+
+    # Create intermediary bridge netdev
+    ip link add name $FASTDP_BRIDGE type bridge
+
+    # Set random MAC
+    ip link set dev $FASTDP_BRIDGE address $(random_mac)
+
+    # Set MTU
+    ip link add name v${CONTAINER_IFNAME}du mtu $MTU type dummy
+    ip link set dev v${CONTAINER_IFNAME}du master $FASTDP_BRIDGE
+    ip link del dev v${CONTAINER_IFNAME}du
+
+    # Link intermediary bridge and datapath
+    if ! ip link set $FASTDP_BRIDGE_IFNAME up ||
+       ! ip link set $BRIDGE_IFNAME up ||
+       ! add_iface_fastdp $BRIDGE_IFNAME || ! ip link set $FASTDP_BRIDGE_IFNAME master $FASTDP_BRIDGE ; then
+        ip link del $BRIDGE_IFNAME >/dev/null 2>&1 || true
+        ip link del $FASTDP_BRIDGE >/dev/null 2>&1 || true
+        docker run --rm --privileged --net=host $IMAGE $COVERAGE_ARGS --delete-datapath --datapath=$BRIDGE >/dev/null 2>&1 || true
+        return 1
+    fi
+
+    ip link set dev $FASTDP_BRIDGE up
+}
+
 init_bridge_bridge() {
     MTU=${WEAVE_MTU:-65535}
 
@@ -513,6 +559,10 @@ ethtool_tx_off_fastdp() {
     true
 }
 
+ethtool_tx_off_bridged_fastdp() {
+    true
+}
+
 ethtool_tx_off_bridge() {
     ethtool -K $1 tx off >/dev/null
 }
@@ -526,6 +576,13 @@ destroy_bridge() {
         fi
     fi
 
+    if [ -d /sys/class/net/$FASTDP_BRIDGE ] ; then
+        ip link del dev $FASTDP_BRIDGE
+    fi
+
+    ip link del $FASTDP_BRIDGE_IFNAME >/dev/null 2>&1 || true
+    ip link del $BRIDGE_IFNAME >/dev/null 2>&1 || true
+
     if [ "$DOCKER_BRIDGE" != "$BRIDGE" ] ; then
         run_iptables -t filter -D FORWARD -i $DOCKER_BRIDGE -o $BRIDGE -j DROP 2>/dev/null || true
     fi
@@ -632,6 +689,10 @@ add_iface_fastdp() {
     docker run --rm --privileged --net=host $IMAGE $COVERAGE_ARGS --datapath=$BRIDGE --add-datapath-iface=$1
 }
 
+add_iface_bridged_fastdp() {
+    ip link set $1 master $FASTDP_BRIDGE
+}
+
 add_iface_bridge() {
     ip link set $1 master $BRIDGE
 }
@@ -669,6 +730,10 @@ router_opts_fastdp() {
     fi
 }
 
+router_opts_bridged_fastdp() {
+    router_opts_fastdp
+}
+
 router_opts_bridge() {
     echo "--iface $CONTAINER_IFNAME"
 }
@@ -689,6 +754,10 @@ setup_router_iface_fastdp() {
     fi
 }
 
+setup_router_iface_bridged_fastdp() {
+    setup_router_iface_fastdp
+}
+
 setup_router_iface_bridge() {
     if ! netnsenter ip link show eth0 >/dev/null ; then
         echo "Perhaps you are running the docker daemon with container networking disabled (-b=none)." >&2
@@ -1466,7 +1535,7 @@ launch_router() {
         fi
     fi
 
-    if [ "$BRIDGE_TYPE" = fastdp ] ; then
+    if [ "$BRIDGE_TYPE" = fastdp -o "$BRIDGE_TYPE" = bridged_fastdp ] ; then
         NETHOST_OPT="--net=host"
         HTTP_IP=127.0.0.1
         # In case there is a lingering veth-weave netdev