Support plaintext credentials as multi-call binary

cmd/docker/docker.go

@@ -19,8 +19,10 @@ import (
 	cliflags "github.com/docker/cli/cli/flags"
 	"github.com/docker/cli/cli/version"
 	platformsignals "github.com/docker/cli/cmd/docker/internal/signals"
+
 	"github.com/docker/docker/api/types/versions"
 	"github.com/docker/docker/errdefs"
+	"github.com/docker/docker/pkg/reexec"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -29,6 +31,10 @@ import (
 )
 
 func main() {
+	if reexec.Init() {
+		return
+	}
+
 	err := dockerMain(context.Background())
 	if err != nil && !errdefs.IsCancelled(err) {
 		_, _ = fmt.Fprintln(os.Stderr, err)

cmd/docker/file_helper.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"os"
+
+	credhelpers "github.com/docker/docker-credential-helpers/credentials"
+	"github.com/docker/docker/pkg/reexec"
+
+	"github.com/docker/cli/cli/config"
+	"github.com/docker/cli/cli/config/credentials"
+	"github.com/docker/cli/cli/config/types"
+)
+
+//nolint:gosec // ignore G101: Potential hardcoded credentials
+const fileCredsHelperBinary = "docker-credential-file"
+
+func init() {
+	reexec.Register(fileCredsHelperBinary, serveFileCredHelper)
+}
+
+func serveFileCredHelper() {
+	configfile := config.LoadDefaultConfigFile(os.Stderr)
+	store := credentials.NewFileStore(configfile)
+	credhelpers.Serve(&FileHelper{
+		fileStore: store,
+	})
+}
+
+var _ credhelpers.Helper = &FileHelper{}
+
+type FileHelper struct {
+	fileStore credentials.Store
+}
+
+func (f *FileHelper) Add(creds *credhelpers.Credentials) error {
+	return f.fileStore.Store(types.AuthConfig{
+		Username:      creds.Username,
+		Password:      creds.Secret,
+		ServerAddress: creds.ServerURL,
+	})
+}
+
+func (f *FileHelper) Delete(serverAddress string) error {
+	return f.fileStore.Erase(serverAddress)
+}
+
+func (f *FileHelper) Get(serverAddress string) (string, string, error) {
+	authConfig, err := f.fileStore.Get(serverAddress)
+	if err != nil {
+		return "", "", err
+	}
+
+	return authConfig.Username, authConfig.Password, nil
+}
+
+func (f *FileHelper) List() (map[string]string, error) {
+	creds := make(map[string]string)
+
+	authConfig, err := f.fileStore.GetAll()
+	if err != nil {
+		return nil, err
+	}
+
+	for k, v := range authConfig {
+		creds[k] = v.Username
+	}
+
+	return creds, nil
+}

vendor/modules.txt

@@ -91,6 +91,7 @@ github.com/docker/docker/pkg/longpath
 github.com/docker/docker/pkg/pools
 github.com/docker/docker/pkg/process
 github.com/docker/docker/pkg/progress
+github.com/docker/docker/pkg/reexec
 github.com/docker/docker/pkg/stdcopy
 github.com/docker/docker/pkg/streamformatter
 github.com/docker/docker/pkg/stringid