vendor: add libcni

vendor/github.com/containernetworking/cni/libcni/api.go

@@ -0,0 +1,219 @@
+// 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.
+
+package libcni
+
+import (
+	"os"
+	"strings"
+
+	"github.com/containernetworking/cni/pkg/invoke"
+	"github.com/containernetworking/cni/pkg/types"
+	"github.com/containernetworking/cni/pkg/version"
+)
+
+type RuntimeConf struct {
+	ContainerID string
+	NetNS       string
+	IfName      string
+	Args        [][2]string
+	// A dictionary of capability-specific data passed by the runtime
+	// to plugins as top-level keys in the 'runtimeConfig' dictionary
+	// of the plugin's stdin data.  libcni will ensure that only keys
+	// in this map which match the capabilities of the plugin are passed
+	// to the plugin
+	CapabilityArgs map[string]interface{}
+}
+
+type NetworkConfig struct {
+	Network *types.NetConf
+	Bytes   []byte
+}
+
+type NetworkConfigList struct {
+	Name       string
+	CNIVersion string
+	Plugins    []*NetworkConfig
+	Bytes      []byte
+}
+
+type CNI interface {
+	AddNetworkList(net *NetworkConfigList, rt *RuntimeConf) (types.Result, error)
+	DelNetworkList(net *NetworkConfigList, rt *RuntimeConf) error
+
+	AddNetwork(net *NetworkConfig, rt *RuntimeConf) (types.Result, error)
+	DelNetwork(net *NetworkConfig, rt *RuntimeConf) error
+}
+
+type CNIConfig struct {
+	Path []string
+}
+
+// CNIConfig implements the CNI interface
+var _ CNI = &CNIConfig{}
+
+func buildOneConfig(list *NetworkConfigList, orig *NetworkConfig, prevResult types.Result, rt *RuntimeConf) (*NetworkConfig, error) {
+	var err error
+
+	inject := map[string]interface{}{
+		"name":       list.Name,
+		"cniVersion": list.CNIVersion,
+	}
+	// Add previous plugin result
+	if prevResult != nil {
+		inject["prevResult"] = prevResult
+	}
+
+	// Ensure every config uses the same name and version
+	orig, err = InjectConf(orig, inject)
+	if err != nil {
+		return nil, err
+	}
+
+	return injectRuntimeConfig(orig, rt)
+}
+
+// This function takes a libcni RuntimeConf structure and injects values into
+// a "runtimeConfig" dictionary in the CNI network configuration JSON that
+// will be passed to the plugin on stdin.
+//
+// Only "capabilities arguments" passed by the runtime are currently injected.
+// These capabilities arguments are filtered through the plugin's advertised
+// capabilities from its config JSON, and any keys in the CapabilityArgs
+// matching plugin capabilities are added to the "runtimeConfig" dictionary
+// sent to the plugin via JSON on stdin.  For exmaple, if the plugin's
+// capabilities include "portMappings", and the CapabilityArgs map includes a
+// "portMappings" key, that key and its value are added to the "runtimeConfig"
+// dictionary to be passed to the plugin's stdin.
+func injectRuntimeConfig(orig *NetworkConfig, rt *RuntimeConf) (*NetworkConfig, error) {
+	var err error
+
+	rc := make(map[string]interface{})
+	for capability, supported := range orig.Network.Capabilities {
+		if !supported {
+			continue
+		}
+		if data, ok := rt.CapabilityArgs[capability]; ok {
+			rc[capability] = data
+		}
+	}
+
+	if len(rc) > 0 {
+		orig, err = InjectConf(orig, map[string]interface{}{"runtimeConfig": rc})
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return orig, nil
+}
+
+// AddNetworkList executes a sequence of plugins with the ADD command
+func (c *CNIConfig) AddNetworkList(list *NetworkConfigList, rt *RuntimeConf) (types.Result, error) {
+	var prevResult types.Result
+	for _, net := range list.Plugins {
+		pluginPath, err := invoke.FindInPath(net.Network.Type, c.Path)
+		if err != nil {
+			return nil, err
+		}
+
+		newConf, err := buildOneConfig(list, net, prevResult, rt)
+		if err != nil {
+			return nil, err
+		}
+
+		prevResult, err = invoke.ExecPluginWithResult(pluginPath, newConf.Bytes, c.args("ADD", rt))
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return prevResult, nil
+}
+
+// DelNetworkList executes a sequence of plugins with the DEL command
+func (c *CNIConfig) DelNetworkList(list *NetworkConfigList, rt *RuntimeConf) error {
+	for i := len(list.Plugins) - 1; i >= 0; i-- {
+		net := list.Plugins[i]
+
+		pluginPath, err := invoke.FindInPath(net.Network.Type, c.Path)
+		if err != nil {
+			return err
+		}
+
+		newConf, err := buildOneConfig(list, net, nil, rt)
+		if err != nil {
+			return err
+		}
+
+		if err := invoke.ExecPluginWithoutResult(pluginPath, newConf.Bytes, c.args("DEL", rt)); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// AddNetwork executes the plugin with the ADD command
+func (c *CNIConfig) AddNetwork(net *NetworkConfig, rt *RuntimeConf) (types.Result, error) {
+	pluginPath, err := invoke.FindInPath(net.Network.Type, c.Path)
+	if err != nil {
+		return nil, err
+	}
+
+	net, err = injectRuntimeConfig(net, rt)
+	if err != nil {
+		return nil, err
+	}
+
+	return invoke.ExecPluginWithResult(pluginPath, net.Bytes, c.args("ADD", rt))
+}
+
+// DelNetwork executes the plugin with the DEL command
+func (c *CNIConfig) DelNetwork(net *NetworkConfig, rt *RuntimeConf) error {
+	pluginPath, err := invoke.FindInPath(net.Network.Type, c.Path)
+	if err != nil {
+		return err
+	}
+
+	net, err = injectRuntimeConfig(net, rt)
+	if err != nil {
+		return err
+	}
+
+	return invoke.ExecPluginWithoutResult(pluginPath, net.Bytes, c.args("DEL", rt))
+}
+
+// GetVersionInfo reports which versions of the CNI spec are supported by
+// the given plugin.
+func (c *CNIConfig) GetVersionInfo(pluginType string) (version.PluginInfo, error) {
+	pluginPath, err := invoke.FindInPath(pluginType, c.Path)
+	if err != nil {
+		return nil, err
+	}
+
+	return invoke.GetVersionInfo(pluginPath)
+}
+
+// =====
+func (c *CNIConfig) args(action string, rt *RuntimeConf) *invoke.Args {
+	return &invoke.Args{
+		Command:     action,
+		ContainerID: rt.ContainerID,
+		NetNS:       rt.NetNS,
+		PluginArgs:  rt.Args,
+		IfName:      rt.IfName,
+		Path:        strings.Join(c.Path, string(os.PathListSeparator)),
+	}
+}