diff options
Diffstat (limited to 'runsc/console/console.go')
-rw-r--r-- | runsc/console/console.go | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/runsc/console/console.go b/runsc/console/console.go new file mode 100644 index 000000000..64b23639a --- /dev/null +++ b/runsc/console/console.go @@ -0,0 +1,63 @@ +// Copyright 2018 The gVisor 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 console contains utilities for working with pty consols in runsc. +package console + +import ( + "fmt" + "net" + "os" + + "github.com/kr/pty" + "golang.org/x/sys/unix" +) + +// NewWithSocket creates pty master/slave pair, sends the master FD over the given +// socket, and returns the slave. +func NewWithSocket(socketPath string) (*os.File, error) { + // Create a new pty master and slave. + ptyMaster, ptySlave, err := pty.Open() + if err != nil { + return nil, fmt.Errorf("opening pty: %v", err) + } + defer ptyMaster.Close() + + // Get a connection to the socket path. + conn, err := net.Dial("unix", socketPath) + if err != nil { + ptySlave.Close() + return nil, fmt.Errorf("dialing socket %q: %v", socketPath, err) + } + defer conn.Close() + uc, ok := conn.(*net.UnixConn) + if !ok { + ptySlave.Close() + return nil, fmt.Errorf("connection is not a UnixConn: %T", conn) + } + socket, err := uc.File() + if err != nil { + ptySlave.Close() + return nil, fmt.Errorf("getting file for unix socket %v: %v", uc, err) + } + defer socket.Close() + + // Send the master FD over the connection. + msg := unix.UnixRights(int(ptyMaster.Fd())) + if err := unix.Sendmsg(int(socket.Fd()), []byte("pty-master"), msg, nil, 0); err != nil { + ptySlave.Close() + return nil, fmt.Errorf("sending console over unix socket %q: %v", socketPath, err) + } + return ptySlave, nil +} |