-# getpasswd in Go [](https://godoc.org/github.com/howeyc/gopass) [](http://travis-ci.org/howeyc/gopass)
-
-Retrieve password from user terminal or piped input without echo.
-
-Verified on BSD, Linux, and Windows.
-
-Example:
-```go
-package main
-
-import "fmt"
-import "github.com/howeyc/gopass"
-
-func main() {
- fmt.Printf("Password: ")
-
- // Silent. For printing *'s use gopass.GetPasswdMasked()
- pass, err := gopass.GetPasswd()
- if err != nil {
- // Handle gopass.ErrInterrupted or getch() read error
- // Test output (masked and unmasked). Delete/backspace actually
- // deletes, overwrites and deletes again. As a result, we need to
- // remove those from the pipe afterwards to mimic the console's
- // interpretation of those bytes.
- w.Close()
- output, err := ioutil.ReadAll(r)
- if err != nil {
- t.Fatal(err.Error())
- }
- var expectedOutput []byte
- if masked {
- expectedOutput = []byte(d.masked)
- } else {
- expectedOutput = []byte("")
- }
- if bytes.Compare(expectedOutput, output) != 0 {
- t.Errorf("Expected output to equal %v (%q) but got %v (%q) instead when masked=%v. %s", expectedOutput, string(expectedOutput), output, string(output), masked, d.reason)
- }
-
- if string(result) != d.password {
- t.Errorf("Expected %q but got %q instead when masked=%v. %s", d.password, result, masked, d.reason)
- }
-
- if leftOnBuffer != d.byesLeft {
- t.Errorf("Expected %v bytes left on buffer but instead got %v when masked=%v. %s", d.byesLeft, leftOnBuffer, masked, d.reason)
- }
- }
- }
-}
-
-// TestPipe ensures we get our expected pipe behavior.
-func TestPipe(t *testing.T) {
- type testData struct {
- input string
- password string
- expError error
- }
- ds := []testData{
- testData{"abc", "abc", io.EOF},
- testData{"abc\n", "abc", nil},
- testData{"abc\r", "abc", nil},
- testData{"abc\r\n", "abc", nil},
- }
-
- for _, d := range ds {
- _, err := pipeToStdin(d.input)
- if err != nil {
- t.Log("Error writing input to stdin:", err)
- t.FailNow()
- }
- pass, err := GetPasswd()
- if string(pass) != d.password {
- t.Errorf("Expected %q but got %q instead.", d.password, string(pass))
- }
- if err != d.expError {
- t.Errorf("Expected %v but got %q instead.", d.expError, err)
- }
- }
-}
-
-// flushStdin reads from stdin for .5 seconds to ensure no bytes are left on
-// the buffer. Returns the number of bytes read.
-func flushStdin() int {
- ch := make(chan byte)
- go func(ch chan byte) {
- reader := bufio.NewReader(os.Stdin)
- for {
- b, err := reader.ReadByte()
- if err != nil { // Maybe log non io.EOF errors, if you want
- close(ch)
- return
- }
- ch <- b
- }
- close(ch)
- }(ch)
-
- numBytes := 0
- for {
- select {
- case _, ok := <-ch:
- if !ok {
- return numBytes
- }
- numBytes++
- case <-time.After(500 * time.Millisecond):
- return numBytes
- }
- }
- return numBytes
-}
-
-// pipeToStdin pipes the given string onto os.Stdin by replacing it with an
-// os.Pipe. The write end of the pipe is closed so that EOF is read after the
-// final byte.
-func pipeToStdin(s string) (int, error) {
- pipeReader, pipeWriter, err := os.Pipe()
- if err != nil {
- fmt.Println("Error getting os pipes:", err)
- os.Exit(1)
- }
- os.Stdin = pipeReader
- w, err := pipeWriter.WriteString(s)
- pipeWriter.Close()
- return w, err
-}
-
-func pipeBytesToStdin(b []byte) (int, error) {
- return pipeToStdin(string(b))
-}
-
-// TestGetPasswd_Err tests errors are properly handled from getch()
-func TestGetPasswd_Err(t *testing.T) {
- var inBuffer *bytes.Buffer
- getch = func(io.Reader) (byte, error) {
- b, err := inBuffer.ReadByte()
- if err != nil {
- return 13, err
- }
- if b == 'z' {
- return 'z', fmt.Errorf("Forced error; byte returned should not be considered accurate.")
- }
- return b, nil
- }
- defer func() { getch = defaultGetCh }()
-
- for input, expectedPassword := range map[string]string{"abc": "abc", "abzc": "ab"} {
- inBuffer = bytes.NewBufferString(input)
- p, err := GetPasswdMasked()
- if string(p) != expectedPassword {
- t.Errorf("Expected %q but got %q instead.", expectedPassword, p)
- }
- if err == nil {
- t.Errorf("Expected error to be returned.")
- }
- }
-}
-
-func TestMaxPasswordLength(t *testing.T) {
- type testData struct {
- input []byte
- expectedErr error
-
- // Helper field to output in case of failure; rather than hundreds of
- // bytes.
- inputDesc string
- }
-
- ds := []testData{
- testData{append(bytes.Repeat([]byte{'a'}, maxLength), '\n'), nil, fmt.Sprintf("%v 'a' bytes followed by a newline", maxLength)},
- testData{append(bytes.Repeat([]byte{'a'}, maxLength+1), '\n'), ErrMaxLengthExceeded, fmt.Sprintf("%v 'a' bytes followed by a newline", maxLength+1)},
- testData{append(bytes.Repeat([]byte{0x00}, maxLength+1), '\n'), ErrMaxLengthExceeded, fmt.Sprintf("%v 0x00 bytes followed by a newline", maxLength+1)},
- }
-
- for _, d := range ds {
- pipeBytesToStdin(d.input)
- _, err := GetPasswd()
- if err != d.expectedErr {
- t.Errorf("Expected error to be %v; isntead got %v from %v", d.expectedErr, err, d.inputDesc)