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Diffstat (limited to 'vendor/github.com/containerd/go-runc/console.go')
-rw-r--r--vendor/github.com/containerd/go-runc/console.go165
1 files changed, 165 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/go-runc/console.go b/vendor/github.com/containerd/go-runc/console.go
new file mode 100644
index 000000000..ff223e427
--- /dev/null
+++ b/vendor/github.com/containerd/go-runc/console.go
@@ -0,0 +1,165 @@
+// +build !windows
+
+/*
+ Copyright The containerd 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 runc
+
+import (
+ "fmt"
+ "io/ioutil"
+ "net"
+ "os"
+ "path/filepath"
+
+ "github.com/containerd/console"
+ "golang.org/x/sys/unix"
+)
+
+// NewConsoleSocket creates a new unix socket at the provided path to accept a
+// pty master created by runc for use by the container
+func NewConsoleSocket(path string) (*Socket, error) {
+ abs, err := filepath.Abs(path)
+ if err != nil {
+ return nil, err
+ }
+ addr, err := net.ResolveUnixAddr("unix", abs)
+ if err != nil {
+ return nil, err
+ }
+ l, err := net.ListenUnix("unix", addr)
+ if err != nil {
+ return nil, err
+ }
+ return &Socket{
+ l: l,
+ }, nil
+}
+
+// NewTempConsoleSocket returns a temp console socket for use with a container
+// On Close(), the socket is deleted
+func NewTempConsoleSocket() (*Socket, error) {
+ runtimeDir := os.Getenv("XDG_RUNTIME_DIR")
+ dir, err := ioutil.TempDir(runtimeDir, "pty")
+ if err != nil {
+ return nil, err
+ }
+ abs, err := filepath.Abs(filepath.Join(dir, "pty.sock"))
+ if err != nil {
+ return nil, err
+ }
+ addr, err := net.ResolveUnixAddr("unix", abs)
+ if err != nil {
+ return nil, err
+ }
+ l, err := net.ListenUnix("unix", addr)
+ if err != nil {
+ return nil, err
+ }
+ if runtimeDir != "" {
+ if err := os.Chmod(abs, 0755|os.ModeSticky); err != nil {
+ return nil, err
+ }
+ }
+ return &Socket{
+ l: l,
+ rmdir: true,
+ }, nil
+}
+
+// Socket is a unix socket that accepts the pty master created by runc
+type Socket struct {
+ rmdir bool
+ l *net.UnixListener
+}
+
+// Path returns the path to the unix socket on disk
+func (c *Socket) Path() string {
+ return c.l.Addr().String()
+}
+
+// recvFd waits for a file descriptor to be sent over the given AF_UNIX
+// socket. The file name of the remote file descriptor will be recreated
+// locally (it is sent as non-auxiliary data in the same payload).
+func recvFd(socket *net.UnixConn) (*os.File, error) {
+ const MaxNameLen = 4096
+ var oobSpace = unix.CmsgSpace(4)
+
+ name := make([]byte, MaxNameLen)
+ oob := make([]byte, oobSpace)
+
+ n, oobn, _, _, err := socket.ReadMsgUnix(name, oob)
+ if err != nil {
+ return nil, err
+ }
+
+ if n >= MaxNameLen || oobn != oobSpace {
+ return nil, fmt.Errorf("recvfd: incorrect number of bytes read (n=%d oobn=%d)", n, oobn)
+ }
+
+ // Truncate.
+ name = name[:n]
+ oob = oob[:oobn]
+
+ scms, err := unix.ParseSocketControlMessage(oob)
+ if err != nil {
+ return nil, err
+ }
+ if len(scms) != 1 {
+ return nil, fmt.Errorf("recvfd: number of SCMs is not 1: %d", len(scms))
+ }
+ scm := scms[0]
+
+ fds, err := unix.ParseUnixRights(&scm)
+ if err != nil {
+ return nil, err
+ }
+ if len(fds) != 1 {
+ return nil, fmt.Errorf("recvfd: number of fds is not 1: %d", len(fds))
+ }
+ fd := uintptr(fds[0])
+
+ return os.NewFile(fd, string(name)), nil
+}
+
+// ReceiveMaster blocks until the socket receives the pty master
+func (c *Socket) ReceiveMaster() (console.Console, error) {
+ conn, err := c.l.Accept()
+ if err != nil {
+ return nil, err
+ }
+ defer conn.Close()
+ uc, ok := conn.(*net.UnixConn)
+ if !ok {
+ return nil, fmt.Errorf("received connection which was not a unix socket")
+ }
+ f, err := recvFd(uc)
+ if err != nil {
+ return nil, err
+ }
+ return console.ConsoleFromFile(f)
+}
+
+// Close closes the unix socket
+func (c *Socket) Close() error {
+ err := c.l.Close()
+ if c.rmdir {
+ if rerr := os.RemoveAll(filepath.Dir(c.Path())); err == nil {
+ err = rerr
+ }
+ }
+ return err
+}