Initial commit

multus/multus.go

@@ -0,0 +1,285 @@
+// Copyright 2015 CNI authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This is a "Multi-plugin".It is a fork of flannel CNI
+// It reads other plugin netconf, and then invoke them, e.g.
+// flannel or sriov plugin.
+
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+
+	"github.com/containernetworking/cni/pkg/invoke"
+	"github.com/containernetworking/cni/pkg/skel"
+	"github.com/containernetworking/cni/pkg/types"
+)
+
+const defaultCNIDir="/var/lib/cni/multus"
+var masterpluginEnabled bool
+
+type NetConf struct {
+	types.NetConf
+	CNIDir    string                   `json:"cniDir"`
+	Delegates []map[string]interface{} `json:"delegates"`
+}
+
+//taken from cni/plugins/meta/flannel/flannel.go
+func isString(i interface{}) bool {
+	_, ok := i.(string)
+	return ok
+}
+
+func isBool(i interface{}) bool {
+	_, ok := i.(bool)
+	return ok
+}
+
+func loadNetConf(bytes []byte) (*NetConf, error) {
+	netconf := &NetConf{}
+	if err := json.Unmarshal(bytes, netconf); err != nil {
+		return nil, fmt.Errorf("failed to load netconf: %v", err)
+	}
+
+	if netconf.Delegates == nil {
+		return nil, fmt.Errorf(`"delegates" is must, refer README.md`)
+	}
+
+	if netconf.CNIDir == "" {
+		netconf.CNIDir = defaultCNIDir
+	}
+
+	return netconf, nil
+}
+
+func saveScratchNetConf(containerID, dataDir string, netconf []byte) error {
+	if err := os.MkdirAll(dataDir, 0700); err != nil {
+		return fmt.Errorf("failed to create the multus data directory(%q): %v", dataDir, err)
+	}
+
+	path := filepath.Join(dataDir, containerID)
+
+	err := ioutil.WriteFile(path, netconf, 0600)
+	if err != nil {
+		return fmt.Errorf("failed to write container data in the path(%q): %v", path, err)
+	}
+
+	return err
+}
+
+func consumeScratchNetConf(containerID, dataDir string) ([]byte, error) {
+	path := filepath.Join(dataDir, containerID)
+	defer os.Remove(path)
+
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read container data in the path(%q): %v", path, err)
+	}
+
+	return data, err
+}
+
+func getifname() (f func() string) {
+	var interfaceIndex int
+	f = func() string {
+		ifname := fmt.Sprintf("net%d",interfaceIndex)
+		interfaceIndex++
+		return ifname
+	}
+
+	return
+}
+
+func saveDelegates(containerID, dataDir string, delegates []map[string]interface{}) error {
+	delegatesBytes, err := json.Marshal(delegates)
+	if err != nil {
+		return fmt.Errorf("error serializing delegate netconf: %v", err)
+	}
+
+	if err = saveScratchNetConf(containerID, dataDir, delegatesBytes); err != nil {
+		return fmt.Errorf("error in saving the  delegates : %v", err)
+	}
+
+	return err
+}
+
+func checkDelegate(netconf map[string]interface{}) error {
+	if netconf["type"] == nil {
+		return fmt.Errorf("delegate must have the field 'type'")
+	}
+
+	if !isString(netconf["type"]) {
+		return fmt.Errorf("delegate field 'type' must be a string")
+	}
+
+	if netconf["masterplugin"] != nil {
+		if !isBool(netconf["masterplugin"]) {
+			return fmt.Errorf("delegate field 'masterplugin' must be a bool")
+		}
+	}
+
+	if netconf["masterplugin"] != nil {
+		if netconf["masterplugin"].(bool) != false && masterpluginEnabled != true {
+			masterpluginEnabled = true
+		} else if netconf["masterplugin"].(bool) != false && masterpluginEnabled == true {
+			return fmt.Errorf("only one delegate can have 'masterplugin'")
+		}
+	}
+	return nil
+}
+
+func isMasterplugin(netconf map[string]interface{}) bool {
+	if netconf["masterplugin"] == nil {
+		return false
+	}
+
+	if netconf["masterplugin"].(bool) == true {
+		return true
+	}
+
+	return false
+}
+
+
+func delegateAdd(podif func() string, argif string, netconf map[string]interface{}, onlyMaster bool) (bool, error) {
+	netconfBytes, err := json.Marshal(netconf)
+	if err != nil {
+		return true, fmt.Errorf("Multus: error serializing multus delegate netconf: %v", err)
+	}
+
+	if isMasterplugin(netconf) != onlyMaster {
+		return true, nil
+	}
+
+	if !isMasterplugin(netconf) {
+		if os.Setenv("CNI_IFNAME", podif()) != nil {
+			return true, fmt.Errorf("Multus: error in setting CNI_IFNAME")
+		}
+	} else {
+		if os.Setenv("CNI_IFNAME", argif) != nil {
+			return true, fmt.Errorf("Multus: error in setting CNI_IFNAME")
+		}
+	}
+
+	result, err := invoke.DelegateAdd(netconf["type"].(string), netconfBytes)
+	if err != nil {
+		return true, fmt.Errorf("Multus: error in invoke Delegate add - %q: %v", netconf["type"].(string), err)
+	}
+
+	if !isMasterplugin(netconf) {
+		return true, nil
+	}
+
+	return false, result.Print()
+}
+
+func delegateDel(podif func() string, argif string, netconf map[string]interface{}) error {
+	netconfBytes, err := json.Marshal(netconf)
+	if err != nil {
+		return fmt.Errorf("Multus: error serializing multus delegate netconf: %v", err)
+	}
+
+	if !isMasterplugin(netconf) {
+		if os.Setenv("CNI_IFNAME", podif()) != nil {
+			return fmt.Errorf("Multus: error in setting CNI_IFNAME")
+		}
+	} else {
+		if os.Setenv("CNI_IFNAME", argif) != nil {
+			return fmt.Errorf("Multus: error in setting CNI_IFNAME")
+		}
+	}
+
+	err = invoke.DelegateDel(netconf["type"].(string), netconfBytes)
+	if err != nil {
+		return fmt.Errorf("Multus: error in invoke Delegate del - %q: %v", netconf["type"].(string), err)
+	}
+
+	return err
+}
+
+func cmdAdd(args *skel.CmdArgs) error {
+	var result error
+	n, err := loadNetConf(args.StdinData)
+	if err != nil {
+		return err
+	}
+
+	for _, delegate := range n.Delegates {
+		if err := checkDelegate(delegate); err != nil {
+			return fmt.Errorf("Multus: Err in delegate conf: %v", err)
+		}
+	}
+
+	if err := saveDelegates(args.ContainerID, n.CNIDir, n.Delegates); err != nil {
+		return fmt.Errorf("Multus: Err in saving the delegates: %v", err)
+	}
+
+	podifName := getifname()
+	for _, delegate := range n.Delegates {
+		err,r := delegateAdd(podifName, args.IfName, delegate, true)
+		if(err != true) {
+			result = r
+		} else if (err != false) && r !=nil {
+			return r
+		}
+	}
+
+	for _, delegate := range n.Delegates {
+		err,r := delegateAdd(podifName, args.IfName, delegate, false)
+		if(err != true) {
+			result = r
+		} else if (err != false) && r !=nil {
+			return r
+		}
+	}
+
+	return result
+}
+
+func cmdDel(args *skel.CmdArgs) error {
+	var result error
+	in, err := loadNetConf(args.StdinData)
+	if err != nil {
+		return err
+	}
+
+	netconfBytes, err := consumeScratchNetConf(args.ContainerID, in.CNIDir)
+	if err != nil {
+		return fmt.Errorf("Multus: Err in  reading the delegates: %v", err)
+	}
+
+	var Delegates []map[string]interface{}
+	if err := json.Unmarshal(netconfBytes, &Delegates); err != nil {
+		return fmt.Errorf("Multus: failed to load netconf: %v", err)
+	}
+
+	podifName := getifname()
+	for _, delegate := range Delegates {
+		r := delegateDel(podifName, args.IfName, delegate)
+		if r != nil {
+			return r
+		}
+		result = r
+	}
+
+	return result
+}
+
+func main() {
+	skel.PluginMain(cmdAdd, cmdDel)
+}