vendor: Vendor the latest CNI plugins

Vendor cni plugin repo to use the latest code for
setting up network namespaces.

Signed-off-by: Archana Shinde <archana.m.shinde@intel.com>
This commit is contained in:
Archana Shinde 2019-10-07 13:22:25 -07:00
parent 86d8346d0c
commit c0995c6201
8 changed files with 158 additions and 816 deletions

12
Gopkg.lock generated
View File

@ -159,19 +159,11 @@
revision = "2a93cfde8c20b23de8eb84a5adbc234ddf7a9e8d" revision = "2a93cfde8c20b23de8eb84a5adbc234ddf7a9e8d"
[[projects]] [[projects]]
digest = "1:827ed8a74e55981880c4d77f8472d638bceb899188104ba7bf24a9548fd97292" digest = "1:bcf22f6210505381c098d3ab8c039b1c435b6ee1e4cbb51563310c79328e1d28"
name = "github.com/containernetworking/cni"
packages = ["pkg/types"]
pruneopts = "NUT"
revision = "a7885cb6f8ab03fba07852ded351e4f5e7a112bf"
version = "v0.6.0"
[[projects]]
digest = "1:1552ba1ba0d0f3596966cca53601a5f59c257ca7ace87f41708a2480835c5286"
name = "github.com/containernetworking/plugins" name = "github.com/containernetworking/plugins"
packages = ["pkg/ns"] packages = ["pkg/ns"]
pruneopts = "NUT" pruneopts = "NUT"
revision = "7f98c94613021d8b57acfa1a2f0c8d0f6fd7ae5a" revision = "485be65581341430f9106a194a98f0f2412245fb"
[[projects]] [[projects]]
digest = "1:6f614c5193761d29b3184a170380672cafd025306261ce7810e2dd99907184c4" digest = "1:6f614c5193761d29b3184a170380672cafd025306261ce7810e2dd99907184c4"

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@ -1,6 +1,6 @@
[[constraint]] [[constraint]]
name = "github.com/containernetworking/plugins" name = "github.com/containernetworking/plugins"
revision = "7f98c94613021d8b57acfa1a2f0c8d0f6fd7ae5a" revision = "485be65581341430f9106a194a98f0f2412245fb"
[[constraint]] [[constraint]]
name = "github.com/go-ini/ini" name = "github.com/go-ini/ini"

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@ -1,202 +0,0 @@
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@ -1,112 +0,0 @@
// 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 types
import (
"encoding"
"fmt"
"reflect"
"strings"
)
// UnmarshallableBool typedef for builtin bool
// because builtin type's methods can't be declared
type UnmarshallableBool bool
// UnmarshalText implements the encoding.TextUnmarshaler interface.
// Returns boolean true if the string is "1" or "[Tt]rue"
// Returns boolean false if the string is "0" or "[Ff]alse"
func (b *UnmarshallableBool) UnmarshalText(data []byte) error {
s := strings.ToLower(string(data))
switch s {
case "1", "true":
*b = true
case "0", "false":
*b = false
default:
return fmt.Errorf("Boolean unmarshal error: invalid input %s", s)
}
return nil
}
// UnmarshallableString typedef for builtin string
type UnmarshallableString string
// UnmarshalText implements the encoding.TextUnmarshaler interface.
// Returns the string
func (s *UnmarshallableString) UnmarshalText(data []byte) error {
*s = UnmarshallableString(data)
return nil
}
// CommonArgs contains the IgnoreUnknown argument
// and must be embedded by all Arg structs
type CommonArgs struct {
IgnoreUnknown UnmarshallableBool `json:"ignoreunknown,omitempty"`
}
// GetKeyField is a helper function to receive Values
// Values that represent a pointer to a struct
func GetKeyField(keyString string, v reflect.Value) reflect.Value {
return v.Elem().FieldByName(keyString)
}
// UnmarshalableArgsError is used to indicate error unmarshalling args
// from the args-string in the form "K=V;K2=V2;..."
type UnmarshalableArgsError struct {
error
}
// LoadArgs parses args from a string in the form "K=V;K2=V2;..."
func LoadArgs(args string, container interface{}) error {
if args == "" {
return nil
}
containerValue := reflect.ValueOf(container)
pairs := strings.Split(args, ";")
unknownArgs := []string{}
for _, pair := range pairs {
kv := strings.Split(pair, "=")
if len(kv) != 2 {
return fmt.Errorf("ARGS: invalid pair %q", pair)
}
keyString := kv[0]
valueString := kv[1]
keyField := GetKeyField(keyString, containerValue)
if !keyField.IsValid() {
unknownArgs = append(unknownArgs, pair)
continue
}
keyFieldIface := keyField.Addr().Interface()
u, ok := keyFieldIface.(encoding.TextUnmarshaler)
if !ok {
return UnmarshalableArgsError{fmt.Errorf(
"ARGS: cannot unmarshal into field '%s' - type '%s' does not implement encoding.TextUnmarshaler",
keyString, reflect.TypeOf(keyFieldIface))}
}
err := u.UnmarshalText([]byte(valueString))
if err != nil {
return fmt.Errorf("ARGS: error parsing value of pair %q: %v)", pair, err)
}
}
isIgnoreUnknown := GetKeyField("IgnoreUnknown", containerValue).Bool()
if len(unknownArgs) > 0 && !isIgnoreUnknown {
return fmt.Errorf("ARGS: unknown args %q", unknownArgs)
}
return nil
}

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@ -1,189 +0,0 @@
// 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 types
import (
"encoding/json"
"errors"
"fmt"
"net"
"os"
)
// like net.IPNet but adds JSON marshalling and unmarshalling
type IPNet net.IPNet
// ParseCIDR takes a string like "10.2.3.1/24" and
// return IPNet with "10.2.3.1" and /24 mask
func ParseCIDR(s string) (*net.IPNet, error) {
ip, ipn, err := net.ParseCIDR(s)
if err != nil {
return nil, err
}
ipn.IP = ip
return ipn, nil
}
func (n IPNet) MarshalJSON() ([]byte, error) {
return json.Marshal((*net.IPNet)(&n).String())
}
func (n *IPNet) UnmarshalJSON(data []byte) error {
var s string
if err := json.Unmarshal(data, &s); err != nil {
return err
}
tmp, err := ParseCIDR(s)
if err != nil {
return err
}
*n = IPNet(*tmp)
return nil
}
// NetConf describes a network.
type NetConf struct {
CNIVersion string `json:"cniVersion,omitempty"`
Name string `json:"name,omitempty"`
Type string `json:"type,omitempty"`
Capabilities map[string]bool `json:"capabilities,omitempty"`
IPAM struct {
Type string `json:"type,omitempty"`
} `json:"ipam,omitempty"`
DNS DNS `json:"dns"`
}
// NetConfList describes an ordered list of networks.
type NetConfList struct {
CNIVersion string `json:"cniVersion,omitempty"`
Name string `json:"name,omitempty"`
Plugins []*NetConf `json:"plugins,omitempty"`
}
type ResultFactoryFunc func([]byte) (Result, error)
// Result is an interface that provides the result of plugin execution
type Result interface {
// The highest CNI specification result verison the result supports
// without having to convert
Version() string
// Returns the result converted into the requested CNI specification
// result version, or an error if conversion failed
GetAsVersion(version string) (Result, error)
// Prints the result in JSON format to stdout
Print() error
// Returns a JSON string representation of the result
String() string
}
func PrintResult(result Result, version string) error {
newResult, err := result.GetAsVersion(version)
if err != nil {
return err
}
return newResult.Print()
}
// DNS contains values interesting for DNS resolvers
type DNS struct {
Nameservers []string `json:"nameservers,omitempty"`
Domain string `json:"domain,omitempty"`
Search []string `json:"search,omitempty"`
Options []string `json:"options,omitempty"`
}
type Route struct {
Dst net.IPNet
GW net.IP
}
func (r *Route) String() string {
return fmt.Sprintf("%+v", *r)
}
// Well known error codes
// see https://github.com/containernetworking/cni/blob/master/SPEC.md#well-known-error-codes
const (
ErrUnknown uint = iota // 0
ErrIncompatibleCNIVersion // 1
ErrUnsupportedField // 2
)
type Error struct {
Code uint `json:"code"`
Msg string `json:"msg"`
Details string `json:"details,omitempty"`
}
func (e *Error) Error() string {
details := ""
if e.Details != "" {
details = fmt.Sprintf("; %v", e.Details)
}
return fmt.Sprintf("%v%v", e.Msg, details)
}
func (e *Error) Print() error {
return prettyPrint(e)
}
// net.IPNet is not JSON (un)marshallable so this duality is needed
// for our custom IPNet type
// JSON (un)marshallable types
type route struct {
Dst IPNet `json:"dst"`
GW net.IP `json:"gw,omitempty"`
}
func (r *Route) UnmarshalJSON(data []byte) error {
rt := route{}
if err := json.Unmarshal(data, &rt); err != nil {
return err
}
r.Dst = net.IPNet(rt.Dst)
r.GW = rt.GW
return nil
}
func (r *Route) MarshalJSON() ([]byte, error) {
rt := route{
Dst: IPNet(r.Dst),
GW: r.GW,
}
return json.Marshal(rt)
}
func prettyPrint(obj interface{}) error {
data, err := json.MarshalIndent(obj, "", " ")
if err != nil {
return err
}
_, err = os.Stdout.Write(data)
return err
}
// NotImplementedError is used to indicate that a method is not implemented for the given platform
var NotImplementedError = errors.New("Not Implemented")

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@ -1,178 +0,0 @@
// 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 ns
import (
"fmt"
"os"
"runtime"
"sync"
"syscall"
)
type NetNS interface {
// Executes the passed closure in this object's network namespace,
// attempting to restore the original namespace before returning.
// However, since each OS thread can have a different network namespace,
// and Go's thread scheduling is highly variable, callers cannot
// guarantee any specific namespace is set unless operations that
// require that namespace are wrapped with Do(). Also, no code called
// from Do() should call runtime.UnlockOSThread(), or the risk
// of executing code in an incorrect namespace will be greater. See
// https://github.com/golang/go/wiki/LockOSThread for further details.
Do(toRun func(NetNS) error) error
// Sets the current network namespace to this object's network namespace.
// Note that since Go's thread scheduling is highly variable, callers
// cannot guarantee the requested namespace will be the current namespace
// after this function is called; to ensure this wrap operations that
// require the namespace with Do() instead.
Set() error
// Returns the filesystem path representing this object's network namespace
Path() string
// Returns a file descriptor representing this object's network namespace
Fd() uintptr
// Cleans up this instance of the network namespace; if this instance
// is the last user the namespace will be destroyed
Close() error
}
type netNS struct {
file *os.File
mounted bool
closed bool
}
// netNS implements the NetNS interface
var _ NetNS = &netNS{}
const (
// https://github.com/torvalds/linux/blob/master/include/uapi/linux/magic.h
NSFS_MAGIC = 0x6e736673
PROCFS_MAGIC = 0x9fa0
)
type NSPathNotExistErr struct{ msg string }
func (e NSPathNotExistErr) Error() string { return e.msg }
type NSPathNotNSErr struct{ msg string }
func (e NSPathNotNSErr) Error() string { return e.msg }
func IsNSorErr(nspath string) error {
stat := syscall.Statfs_t{}
if err := syscall.Statfs(nspath, &stat); err != nil {
if os.IsNotExist(err) {
err = NSPathNotExistErr{msg: fmt.Sprintf("failed to Statfs %q: %v", nspath, err)}
} else {
err = fmt.Errorf("failed to Statfs %q: %v", nspath, err)
}
return err
}
switch stat.Type {
case PROCFS_MAGIC, NSFS_MAGIC:
return nil
default:
return NSPathNotNSErr{msg: fmt.Sprintf("unknown FS magic on %q: %x", nspath, stat.Type)}
}
}
// Returns an object representing the namespace referred to by @path
func GetNS(nspath string) (NetNS, error) {
err := IsNSorErr(nspath)
if err != nil {
return nil, err
}
fd, err := os.Open(nspath)
if err != nil {
return nil, err
}
return &netNS{file: fd}, nil
}
func (ns *netNS) Path() string {
return ns.file.Name()
}
func (ns *netNS) Fd() uintptr {
return ns.file.Fd()
}
func (ns *netNS) errorIfClosed() error {
if ns.closed {
return fmt.Errorf("%q has already been closed", ns.file.Name())
}
return nil
}
func (ns *netNS) Do(toRun func(NetNS) error) error {
if err := ns.errorIfClosed(); err != nil {
return err
}
containedCall := func(hostNS NetNS) error {
threadNS, err := GetCurrentNS()
if err != nil {
return fmt.Errorf("failed to open current netns: %v", err)
}
defer threadNS.Close()
// switch to target namespace
if err = ns.Set(); err != nil {
return fmt.Errorf("error switching to ns %v: %v", ns.file.Name(), err)
}
defer threadNS.Set() // switch back
return toRun(hostNS)
}
// save a handle to current network namespace
hostNS, err := GetCurrentNS()
if err != nil {
return fmt.Errorf("Failed to open current namespace: %v", err)
}
defer hostNS.Close()
var wg sync.WaitGroup
wg.Add(1)
var innerError error
go func() {
defer wg.Done()
runtime.LockOSThread()
innerError = containedCall(hostNS)
}()
wg.Wait()
return innerError
}
// WithNetNSPath executes the passed closure under the given network
// namespace, restoring the original namespace afterwards.
func WithNetNSPath(nspath string, toRun func(NetNS) error) error {
ns, err := GetNS(nspath)
if err != nil {
return err
}
defer ns.Close()
return ns.Do(toRun)
}

View File

@ -15,12 +15,11 @@
package ns package ns
import ( import (
"crypto/rand"
"fmt" "fmt"
"os" "os"
"path"
"runtime" "runtime"
"sync" "sync"
"syscall"
"golang.org/x/sys/unix" "golang.org/x/sys/unix"
) )
@ -37,82 +36,6 @@ func getCurrentThreadNetNSPath() string {
return fmt.Sprintf("/proc/%d/task/%d/ns/net", os.Getpid(), unix.Gettid()) return fmt.Sprintf("/proc/%d/task/%d/ns/net", os.Getpid(), unix.Gettid())
} }
// Creates a new persistent network namespace and returns an object
// representing that namespace, without switching to it
func NewNS() (NetNS, error) {
const nsRunDir = "/var/run/netns"
b := make([]byte, 16)
_, err := rand.Reader.Read(b)
if err != nil {
return nil, fmt.Errorf("failed to generate random netns name: %v", err)
}
err = os.MkdirAll(nsRunDir, 0755)
if err != nil {
return nil, err
}
// create an empty file at the mount point
nsName := fmt.Sprintf("cni-%x-%x-%x-%x-%x", b[0:4], b[4:6], b[6:8], b[8:10], b[10:])
nsPath := path.Join(nsRunDir, nsName)
mountPointFd, err := os.Create(nsPath)
if err != nil {
return nil, err
}
mountPointFd.Close()
// Ensure the mount point is cleaned up on errors; if the namespace
// was successfully mounted this will have no effect because the file
// is in-use
defer os.RemoveAll(nsPath)
var wg sync.WaitGroup
wg.Add(1)
// do namespace work in a dedicated goroutine, so that we can safely
// Lock/Unlock OSThread without upsetting the lock/unlock state of
// the caller of this function
var fd *os.File
go (func() {
defer wg.Done()
runtime.LockOSThread()
var origNS NetNS
origNS, err = GetNS(getCurrentThreadNetNSPath())
if err != nil {
return
}
defer origNS.Close()
// create a new netns on the current thread
err = unix.Unshare(unix.CLONE_NEWNET)
if err != nil {
return
}
defer origNS.Set()
// bind mount the new netns from the current thread onto the mount point
err = unix.Mount(getCurrentThreadNetNSPath(), nsPath, "none", unix.MS_BIND, "")
if err != nil {
return
}
fd, err = os.Open(nsPath)
if err != nil {
return
}
})()
wg.Wait()
if err != nil {
unix.Unmount(nsPath, unix.MNT_DETACH)
return nil, fmt.Errorf("failed to create namespace: %v", err)
}
return &netNS{file: fd, mounted: true}, nil
}
func (ns *netNS) Close() error { func (ns *netNS) Close() error {
if err := ns.errorIfClosed(); err != nil { if err := ns.errorIfClosed(); err != nil {
return err return err
@ -123,16 +46,6 @@ func (ns *netNS) Close() error {
} }
ns.closed = true ns.closed = true
if ns.mounted {
if err := unix.Unmount(ns.file.Name(), unix.MNT_DETACH); err != nil {
return fmt.Errorf("Failed to unmount namespace %s: %v", ns.file.Name(), err)
}
if err := os.RemoveAll(ns.file.Name()); err != nil {
return fmt.Errorf("Failed to clean up namespace %s: %v", ns.file.Name(), err)
}
ns.mounted = false
}
return nil return nil
} }
@ -147,3 +60,157 @@ func (ns *netNS) Set() error {
return nil return nil
} }
type NetNS interface {
// Executes the passed closure in this object's network namespace,
// attempting to restore the original namespace before returning.
// However, since each OS thread can have a different network namespace,
// and Go's thread scheduling is highly variable, callers cannot
// guarantee any specific namespace is set unless operations that
// require that namespace are wrapped with Do(). Also, no code called
// from Do() should call runtime.UnlockOSThread(), or the risk
// of executing code in an incorrect namespace will be greater. See
// https://github.com/golang/go/wiki/LockOSThread for further details.
Do(toRun func(NetNS) error) error
// Sets the current network namespace to this object's network namespace.
// Note that since Go's thread scheduling is highly variable, callers
// cannot guarantee the requested namespace will be the current namespace
// after this function is called; to ensure this wrap operations that
// require the namespace with Do() instead.
Set() error
// Returns the filesystem path representing this object's network namespace
Path() string
// Returns a file descriptor representing this object's network namespace
Fd() uintptr
// Cleans up this instance of the network namespace; if this instance
// is the last user the namespace will be destroyed
Close() error
}
type netNS struct {
file *os.File
closed bool
}
// netNS implements the NetNS interface
var _ NetNS = &netNS{}
const (
// https://github.com/torvalds/linux/blob/master/include/uapi/linux/magic.h
NSFS_MAGIC = 0x6e736673
PROCFS_MAGIC = 0x9fa0
)
type NSPathNotExistErr struct{ msg string }
func (e NSPathNotExistErr) Error() string { return e.msg }
type NSPathNotNSErr struct{ msg string }
func (e NSPathNotNSErr) Error() string { return e.msg }
func IsNSorErr(nspath string) error {
stat := syscall.Statfs_t{}
if err := syscall.Statfs(nspath, &stat); err != nil {
if os.IsNotExist(err) {
err = NSPathNotExistErr{msg: fmt.Sprintf("failed to Statfs %q: %v", nspath, err)}
} else {
err = fmt.Errorf("failed to Statfs %q: %v", nspath, err)
}
return err
}
switch stat.Type {
case PROCFS_MAGIC, NSFS_MAGIC:
return nil
default:
return NSPathNotNSErr{msg: fmt.Sprintf("unknown FS magic on %q: %x", nspath, stat.Type)}
}
}
// Returns an object representing the namespace referred to by @path
func GetNS(nspath string) (NetNS, error) {
err := IsNSorErr(nspath)
if err != nil {
return nil, err
}
fd, err := os.Open(nspath)
if err != nil {
return nil, err
}
return &netNS{file: fd}, nil
}
func (ns *netNS) Path() string {
return ns.file.Name()
}
func (ns *netNS) Fd() uintptr {
return ns.file.Fd()
}
func (ns *netNS) errorIfClosed() error {
if ns.closed {
return fmt.Errorf("%q has already been closed", ns.file.Name())
}
return nil
}
func (ns *netNS) Do(toRun func(NetNS) error) error {
if err := ns.errorIfClosed(); err != nil {
return err
}
containedCall := func(hostNS NetNS) error {
threadNS, err := GetCurrentNS()
if err != nil {
return fmt.Errorf("failed to open current netns: %v", err)
}
defer threadNS.Close()
// switch to target namespace
if err = ns.Set(); err != nil {
return fmt.Errorf("error switching to ns %v: %v", ns.file.Name(), err)
}
defer threadNS.Set() // switch back
return toRun(hostNS)
}
// save a handle to current network namespace
hostNS, err := GetCurrentNS()
if err != nil {
return fmt.Errorf("Failed to open current namespace: %v", err)
}
defer hostNS.Close()
var wg sync.WaitGroup
wg.Add(1)
var innerError error
go func() {
defer wg.Done()
runtime.LockOSThread()
innerError = containedCall(hostNS)
}()
wg.Wait()
return innerError
}
// WithNetNSPath executes the passed closure under the given network
// namespace, restoring the original namespace afterwards.
func WithNetNSPath(nspath string, toRun func(NetNS) error) error {
ns, err := GetNS(nspath)
if err != nil {
return err
}
defer ns.Close()
return ns.Do(toRun)
}

View File

@ -1,36 +0,0 @@
// Copyright 2015-2017 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.
// +build !linux
package ns
import "github.com/containernetworking/cni/pkg/types"
// Returns an object representing the current OS thread's network namespace
func GetCurrentNS() (NetNS, error) {
return nil, types.NotImplementedError
}
func NewNS() (NetNS, error) {
return nil, types.NotImplementedError
}
func (ns *netNS) Close() error {
return types.NotImplementedError
}
func (ns *netNS) Set() error {
return types.NotImplementedError
}