Add workaround for no password echo

This commit restores the terminal state in case the program is
interrupted while being in password read mode. This ensures the terminal
remains usable, also if the password input is being cancelled.

Signed-off-by: Felix Niederwanger <[email protected]>

Author: grisu48

pkg/auth/auth.go

@@ -10,13 +10,13 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/containers/common/pkg/util"
 	"github.com/containers/image/v5/docker"
 	"github.com/containers/image/v5/docker/reference"
 	"github.com/containers/image/v5/pkg/docker/config"
 	"github.com/containers/image/v5/pkg/sysregistriesv2"
 	"github.com/containers/image/v5/types"
 	"github.com/sirupsen/logrus"
-	terminal "golang.org/x/term"
 )
 
 // GetDefaultAuthFile returns env value REGISTRY_AUTH_FILE as default
@@ -244,11 +244,10 @@ func getUserAndPass(opts *LoginOptions, password, userFromAuthFile string) (user
 	}
 	if password == "" {
 		fmt.Fprint(opts.Stdout, "Password: ")
-		pass, err := terminal.ReadPassword(int(os.Stdin.Fd()))
+		password, err = util.ReadPassword()
 		if err != nil {
 			return "", "", fmt.Errorf("reading password: %w", err)
 		}
-		password = string(pass)
 		fmt.Fprintln(opts.Stdout)
 	}
 	return strings.TrimSpace(username), password, err

pkg/util/util.go

@@ -1,6 +1,13 @@
 package util
 
-import "regexp"
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"regexp"
+
+	terminal "golang.org/x/term"
+)
 
 // StringInSlice determines if a string is in a string slice, returns bool
 func StringInSlice(s string, sl []string) bool {
@@ -22,3 +29,31 @@ func StringMatchRegexSlice(s string, re []string) bool {
 	}
 	return false
 }
+
+// ReadPassword reads a password from the terminal and restores the terminal state on interruption
+func ReadPassword() (string, error) {
+	var err error
+	var password []byte
+	// Store and restore the terminal status on interruptions to
+	// avoid that the terminal remains in the password state
+	// This is necessary as a workaround for https://github.com/golang/go/issues/31180
+	stdin := int(os.Stdin.Fd())
+	oldState, err := terminal.GetState(stdin)
+	if err != nil {
+		oldState = nil
+	}
+	sigch := make(chan os.Signal, 1)
+	defer close(sigch)
+	signal.Notify(sigch, os.Interrupt)
+	go func() {
+		for range sigch {
+			if oldState != nil {
+				terminal.Restore(stdin, oldState)
+			}
+			err = fmt.Errorf("interrupted")
+		}
+	}()
+	password, err = terminal.ReadPassword(stdin)
+	signal.Reset(os.Interrupt)
+	return string(password), err
+}