CNI plugin implemented as script that docker runs plugin container,

installed via `weave setup`

prog/plugin/main.go

@@ -26,6 +26,7 @@ var version = "(unreleased version)"
 func main() {
 	var (
 		justVersion      bool
+		cniNet, cniIpam  bool
 		address          string
 		meshAddress      string
 		logLevel         string
@@ -33,6 +34,8 @@ func main() {
 	)
 
 	flag.BoolVar(&justVersion, "version", false, "print version and exit")
+	flag.BoolVar(&cniNet, "cni-net", false, "act as a CNI network plugin")
+	flag.BoolVar(&cniIpam, "cni-ipam", false, "act as a CNI IPAM plugin")
 	flag.StringVar(&logLevel, "log-level", "info", "logging level (debug, info, warning, error)")
 	flag.StringVar(&address, "socket", "/run/docker/plugins/weave.sock", "socket on which to listen")
 	flag.StringVar(&meshAddress, "meshsocket", "/run/docker/plugins/weavemesh.sock", "socket on which to listen in mesh mode")
@@ -50,11 +53,11 @@ func main() {
 	weave := weaveapi.NewClient(os.Getenv("WEAVE_HTTP_ADDR"), Log)
 
 	switch {
-	case strings.HasSuffix(os.Args[0], "weave-ipam"):
+	case cniIpam || strings.HasSuffix(os.Args[0], "weave-ipam"):
 		i := ipamplugin.NewIpam(weave)
 		cni.PluginMain(i.CmdAdd, i.CmdDel)
 		os.Exit(0)
-	case strings.HasSuffix(os.Args[0], "weave"):
+	case cniNet || strings.HasSuffix(os.Args[0], "weave-net"):
 		n := netplugin.NewCNIPlugin(weave)
 		cni.PluginMain(n.CmdAdd, n.CmdDel)
 		os.Exit(0)

weave

@@ -115,10 +115,35 @@ docker_run_options() {
     echo --privileged --net=host $(docker_sock_options)
 }
 
+docker_exec_cni_options() {
+    [ "$1" = "setup" ] && echo -v /etc/cni:/etc/cni -v /opt/cni:/opt/cni
+}
+
+create_cni_script() {
+    cat >"$1" <<EOF
+#!/bin/sh
+docker run --rm --privileged --net=host --pid=host -i \\
+ -e CNI_VERSION -e CNI_COMMAND -e CNI_CONTAINERID -e CNI_NETNS \\
+ -e CNI_IFNAME -e CNI_ARGS -e CNI_PATH \\
+ $PLUGIN_IMAGE "$2"
+EOF
+    chmod a+x "$1"
+}
+
+create_cni_config() {
+    cat >"$1" <<EOF
+{
+    "name": "weave",
+    "type": "weave-net"
+}
+EOF
+}
+
 exec_remote() {
     docker $DOCKER_CLIENT_ARGS run --rm \
         $(docker_run_options) \
         --pid=host \
+        $(docker_exec_cni_options "$@") \
         -e DOCKERHUB_USER="$DOCKERHUB_USER" \
         -e WEAVE_VERSION \
         -e WEAVE_DEBUG \
@@ -1836,6 +1861,13 @@ case "$COMMAND" in
         for img in $IMAGE $EXEC_IMAGE $PLUGIN_IMAGE ; do
             docker pull $img
         done
+        if [ -d /opt/cni/bin ] ; then
+            create_cni_script /opt/cni/bin/weave-net  --cni-net
+            create_cni_script /opt/cni/bin/weave-ipam --cni-ipam
+        fi
+        if [ -d /etc/cni/net.d -a ! -f /etc/cni/net.d/10-weave.conf ] ; then
+            create_cni_config /etc/cni/net.d/10-weave.conf
+        fi
         ;;
     version)
         [ $# -eq 0 ] || usage