// ReadPassword reads a line of input from a terminal without local echo. This
// is commonly used for inputting passwords and other sensitive data. The slice
// returned does not include the \n.
// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
func ReadPassword(fd int) ([]byte, error) {
val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
if err != nil {
return nil, err
}
oldState := *val
newState := oldState
newState.Lflag &^= syscall.ECHO
newState.Lflag |= syscall.ICANON | syscall.ISIG
newState.Iflag |= syscall.ICRNL
err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState)
if err != nil {
return nil, err
}
// XXX what about resetting the terminal after a signal like Control-C?
// XXX or is ISIG sufficient?
defer func() {
unix.IoctlSetTermios(fd, unix.TCSETS, &oldState)
}()
var buf [16]byte
var ret []byte
for {
n, err := syscall.Read(fd, buf[:])
if err != nil {
return nil, err
}
if n == 0 {
if len(ret) == 0 {
return nil, io.EOF
}
break
}
if buf[n-1] == '\n' {
n--
}
ret = append(ret, buf[:n]...)
if n < len(buf) {
break
}
}
return ret, nil
}
// ReadPassword reads a line of input from a terminal without local echo. This
// is commonly used for inputting passwords and other sensitive data. The slice
// returned does not include the \n.
func ReadPassword(fd int) ([]byte, error) {
// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
if err != nil {
return nil, err
}
oldState := *val
newState := oldState
newState.Lflag &^= syscall.ECHO
newState.Lflag |= syscall.ICANON | syscall.ISIG
newState.Iflag |= syscall.ICRNL
err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState)
if err != nil {
return nil, err
}
defer unix.IoctlSetTermios(fd, unix.TCSETS, &oldState)
var buf [16]byte
var ret []byte
for {
n, err := syscall.Read(fd, buf[:])
if err != nil {
return nil, err
}
if n == 0 {
if len(ret) == 0 {
return nil, io.EOF
}
break
}
if buf[n-1] == '\n' {
n--
}
ret = append(ret, buf[:n]...)
if n < len(buf) {
break
}
}
return ret, nil
}
func read(f *os.File) (string, error) {
fd := int(f.Fd())
if !isTerminal(fd) {
return "", fmt.Errorf("File descriptor %d is not a terminal", fd)
}
oldState, err := makeRaw(fd)
if err != nil {
return "", err
}
defer unix.IoctlSetTermios(fd, unix.TCSETS, oldState)
return readline(f)
}
// makeRaw puts the terminal connected to the given file descriptor into raw
// mode and returns the previous state of the terminal so that it can be
// restored.
// Source: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
func makeRaw(fd int) (*unix.Termios, error) {
oldTermiosPtr, err := unix.IoctlGetTermios(int(fd), unix.TCGETS)
if err != nil {
return nil, err
}
oldTermios := *oldTermiosPtr
newTermios := oldTermios
newTermios.Lflag &^= syscall.ECHO | syscall.ECHOE | syscall.ECHOK | syscall.ECHONL
if err := unix.IoctlSetTermios(fd, unix.TCSETS, &newTermios); err != nil {
return nil, err
}
return oldTermiosPtr, nil
}
// makeRaw puts the terminal connected to the given file descriptor into raw
// mode and returns the previous state of the terminal so that it can be
// restored.
// Source: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
func makeRaw(fd uintptr) (*terminalState, error) {
oldTermiosPtr, err := unix.IoctlGetTermios(int(fd), unix.TCGETS)
if err != nil {
return nil, err
}
oldTermios := *oldTermiosPtr
newTermios := oldTermios
newTermios.Lflag &^= syscall.ECHO | syscall.ECHOE | syscall.ECHOK | syscall.ECHONL
if err := unix.IoctlSetTermios(int(fd), unix.TCSETS, &newTermios); err != nil {
return nil, err
}
return &terminalState{
state: oldTermiosPtr,
}, nil
}
func restore(fd uintptr, oldState *terminalState) error {
return unix.IoctlSetTermios(int(fd), unix.TCSETS, oldState.state)
}
// Tcsetattr sets the current serial port settings.
func Tcsetattr(fd, action uintptr, argp *syscall.Termios) error {
return unix.IoctlSetTermios(int(fd), int(action), (*unix.Termios)(argp))
}