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authorValentin Rothberg <rothberg@redhat.com>2019-01-08 14:52:57 +0100
committerValentin Rothberg <rothberg@redhat.com>2019-01-11 13:38:11 +0100
commitbd40dcfc2bc7c9014ea1f33482fb63aacbcdfe87 (patch)
tree5f06e4e289f16d9164d692590a3fe6541b5384cf /vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go
parent545f24421247c9f6251a634764db3f8f8070a812 (diff)
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vendor: update everything
* If possible, update each dependency to the latest available version. * Use releases over commit IDs and avoid vendoring branches. Signed-off-by: Valentin Rothberg <rothberg@redhat.com>
Diffstat (limited to 'vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go')
-rw-r--r--vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go93
1 files changed, 91 insertions, 2 deletions
diff --git a/vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go b/vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go
index 31ad5f622..4ce989467 100644
--- a/vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go
+++ b/vendor/github.com/containernetworking/plugins/pkg/ns/ns_linux.go
@@ -15,8 +15,10 @@
package ns
import (
+ "crypto/rand"
"fmt"
"os"
+ "path"
"runtime"
"sync"
"syscall"
@@ -36,6 +38,82 @@ func getCurrentThreadNetNSPath() string {
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 {
if err := ns.errorIfClosed(); err != nil {
return err
@@ -46,6 +124,16 @@ func (ns *netNS) Close() error {
}
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
}
@@ -92,8 +180,9 @@ type NetNS interface {
}
type netNS struct {
- file *os.File
- closed bool
+ file *os.File
+ mounted bool
+ closed bool
}
// netNS implements the NetNS interface