func SendRequest(c *net.UnixConn, req *server.Request) error {
payload, err := json.Marshal(req)
if err != nil {
return err
}
err = binary.Write(c, binary.BigEndian, uint32(len(payload)))
if err != nil {
return err
}
n, err := c.Write(payload)
if err != nil {
return err
} else if n != len(payload) {
return fmt.Errorf("Failed to write full payload, expected %v, wrote %v", len(payload), n)
}
if !req.HasFds {
return nil
}
// Send filedescriptors with a 1 byte message.
var oob []byte
oob = syscall.UnixRights(req.Fds...)
payload = make([]byte, 1)
n, oobn, err := c.WriteMsgUnix(payload, oob, nil)
if err != nil {
return err
} else if n != len(payload) || oobn != len(oob) {
return fmt.Errorf("Error writing to socket, expected n=%v got %v, oob=%v got %v", len(payload), n, len(oob), oobn)
}
return nil
}
func writeData(conn *net.UnixConn, files []*os.File, pid int, responseErr error) {
var errMsg string = ""
if responseErr != nil {
errMsg = responseErr.Error()
}
response := &Response{
Pid: pid,
ErrMessage: errMsg,
}
responseJson, _ := json.Marshal(response) // Ignore error
args := make([]int, len(files))
for i, f := range files {
args[i] = int(f.Fd())
}
resp := syscall.UnixRights(args...)
conn.WriteMsgUnix(responseJson, resp, nil) // Ignore error
// Close the files whose descriptors have been sent to the host to ensure that
// a close on the host takes effect in a timely fashion.
for _, file := range files {
file.Close() // Ignore error
}
}
func WriteFile(c *net.UnixConn, file *os.File, timeout time.Duration) error {
if timeout > 0 {
deadline := time.Now().Add(timeout)
if err := c.SetWriteDeadline(deadline); err != nil {
return err
}
}
oob := syscall.UnixRights(int(file.Fd()))
_, _, err := c.WriteMsgUnix(nil, oob, nil)
return err
}
func RemoteSendCredentials(conn *net.UnixConn) error {
ucred := &syscall.Ucred{
Pid: int32(os.Getpid()),
Uid: uint32(os.Getuid()),
Gid: uint32(os.Getgid()),
}
oob := syscall.UnixCredentials(ucred)
_, _, err := conn.WriteMsgUnix(nil, oob, nil)
return err
}
func (fd Fd) writeTo(c *net.UnixConn) error {
var b []byte
oob := syscall.UnixRights(int(fd))
_, oobn, err := c.WriteMsgUnix(b, oob, nil)
if err != nil {
return err
}
if oobn != len(oob) {
return fmt.Errorf("expected to write %d oob bytes, wrote %d", len(oob), oobn)
}
return nil
}
func SendFd(conn *net.UnixConn, file *os.File) error {
rights := syscall.UnixRights(int(file.Fd()))
dummy := []byte("x")
n, oobn, err := conn.WriteMsgUnix(dummy, rights, nil)
if err != nil {
return fmt.Errorf("sendfd: err %v", err)
}
if n != len(dummy) {
return fmt.Errorf("sendfd: short write %v", conn)
}
if oobn != len(rights) {
return fmt.Errorf("sendfd: short oob write %v", conn)
}
return nil
}
func SendWaylandMessage(conn *net.UnixConn, m *Message) error {
header := &bytes.Buffer{}
// calculate message total size
m.size = uint32(m.data.Len() + 8)
binary.Write(header, binary.LittleEndian, m.Id)
binary.Write(header, binary.LittleEndian, m.size<<16|m.Opcode&0x0000ffff)
d, c, err := conn.WriteMsgUnix(append(header.Bytes(), m.data.Bytes()...), m.control.Bytes(), nil)
if err != nil {
panic(err.Error())
}
if c != m.control.Len() || d != (header.Len()+m.data.Len()) {
panic("WriteMsgUnix failed.")
}
return err
}
func writeData(conn *net.UnixConn, response *container_daemon.ResponseMessage) {
data, _ := json.Marshal(response) // Ignore error
args := make([]int, len(response.Files))
for i, f := range response.Files {
args[i] = int(f.Fd())
}
oobData := syscall.UnixRights(args...)
conn.WriteMsgUnix(data, oobData, nil) // Ignore error
// Close the files whose descriptors have been sent to the host to ensure that
// a close on the host takes effect in a timely fashion.
for _, file := range response.Files {
file.Close() // Ignore error
}
}
// passFDChild is the child process used by TestPassFD.
func passFDChild() {
defer os.Exit(0)
// Look for our fd. It should be fd 3, but we work around an fd leak
// bug here (http://golang.org/issue/2603) to let it be elsewhere.
var uc *net.UnixConn
for fd := uintptr(3); fd <= 10; fd++ {
f := os.NewFile(fd, "unix-conn")
var ok bool
netc, _ := net.FileConn(f)
uc, ok = netc.(*net.UnixConn)
if ok {
break
}
}
if uc == nil {
fmt.Println("failed to find unix fd")
return
}
// Make a file f to send to our parent process on uc.
// We make it in tempDir, which our parent will clean up.
flag.Parse()
tempDir := flag.Arg(0)
f, err := ioutil.TempFile(tempDir, "")
if err != nil {
fmt.Printf("TempFile: %v", err)
return
}
f.Write([]byte("Hello from child process!\n"))
f.Seek(0, 0)
rights := syscall.UnixRights(int(f.Fd()))
dummyByte := []byte("x")
n, oobn, err := uc.WriteMsgUnix(dummyByte, rights, nil)
if err != nil {
fmt.Printf("WriteMsgUnix: %v", err)
return
}
if n != 1 || oobn != len(rights) {
fmt.Printf("WriteMsgUnix = %d, %d; want 1, %d", n, oobn, len(rights))
return
}
}
// Send File over UnixConn
func SendFD(conn *net.UnixConn, file *os.File) (err error) {
cmsgb := make([]byte, CmsgSpace(unsafe.Sizeof(int(0))))
cms := (*syscall.Cmsghdr)(unsafe.Pointer(&cmsgb[0]))
cms.Len = CmsgLen(unsafe.Sizeof(int(0)))
cms.Level = 1
cms.Type = 1
fdnum := file.Fd()
fdArea := cmsgb[unsafe.Sizeof(syscall.Cmsghdr{}):]
fdArea[0] = byte(fdnum)
fdArea[1] = byte(fdnum >> 8)
fdArea[2] = byte(fdnum >> 16)
fdArea[3] = byte(fdnum >> 24)
_, _, err = conn.WriteMsgUnix([]byte{}, cmsgb, nil)
return
}
func sendUnix(conn *net.UnixConn, data []byte, fds ...int) error {
_, _, err := conn.WriteMsgUnix(data, syscall.UnixRights(fds...), nil)
return err
}