add specific authfile options to copy (and sync) command.

With additional prefixed flags for authfiles, it is possible to override the shared authfile flag to use different authfiles for src and dest registries. This is an important feature if the two registries have the same domain (but different paths) and require separate credentials.

Closes #773.

Signed-off-by: Daniel Strobusch <1847260+dastrobu@users.noreply.github.com>

.gitignore

@@ -1,3 +1,6 @@
 *.1
 /layers-*
 /skopeo
+
+# ignore JetBrains IDEs (GoLand) config folder
+.idea

cmd/skopeo/utils.go

@@ -56,6 +56,7 @@ func sharedImageFlags() ([]cli.Flag, *sharedImageOptions) {
 type dockerImageOptions struct {
 	global         *globalOptions      // May be shared across several imageOptions instances.
 	shared         *sharedImageOptions // May be shared across several imageOptions instances.
+	authFilePath   optionalString      // Path to a */containers/auth.json (prefixed version to override shared image option).
 	credsOption    optionalString      // username[:password] for accessing a registry
 	dockerCertPath string              // A directory using Docker-like *.{crt,cert,key} files for connecting to a registry or a daemon
 	tlsVerify      optionalBool        // Require HTTPS and verify certificates (for docker: and docker-daemon:)
@@ -87,7 +88,18 @@ func dockerImageFlags(global *globalOptions, shared *sharedImageOptions, flagPre
 		credsOptionExtra += "," + credsOptionAlias
 	}
 
-	return []cli.Flag{
+	var flags []cli.Flag
+	if flagPrefix != "" {
+		// the non-prefixed flag is handled by a shared flag.
+		flags = append(flags,
+			cli.GenericFlag{
+				Name:  flagPrefix + "authfile",
+				Usage: "path of the authentication file. Default is ${XDG_RUNTIME_DIR}/containers/auth.json",
+				Value: newOptionalStringValue(&opts.authFilePath),
+			},
+		)
+	}
+	flags = append(flags,
 		cli.GenericFlag{
 			Name:  flagPrefix + "creds" + credsOptionExtra,
 			Usage: "Use `USERNAME[:PASSWORD]` for accessing the registry",
@@ -108,7 +120,8 @@ func dockerImageFlags(global *globalOptions, shared *sharedImageOptions, flagPre
 			Usage:       "Access the registry anonymously",
 			Destination: &opts.noCreds,
 		},
-	}, &opts
+	)
+	return flags, &opts
 }
 
 // imageFlags prepares a collection of CLI flags writing into imageOptions, and the managed imageOptions structure.
@@ -143,6 +156,9 @@ func (opts *imageOptions) newSystemContext() (*types.SystemContext, error) {
 		DockerDaemonCertPath:     opts.dockerCertPath,
 		SystemRegistriesConfPath: opts.global.registriesConfPath,
 	}
+	if opts.dockerImageOptions.authFilePath.present {
+		ctx.AuthFilePath = opts.dockerImageOptions.authFilePath.value
+	}
 	if opts.tlsVerify.present {
 		ctx.DockerDaemonInsecureSkipTLSVerify = !opts.tlsVerify.value
 	}

cmd/skopeo/utils_test.go

@@ -54,6 +54,7 @@ func TestImageOptionsNewSystemContext(t *testing.T) {
 		"--override-os", "overridden-os",
 	}, []string{
 		"--authfile", "/srv/authfile",
+		"--dest-authfile", "/srv/dest-authfile",
 		"--dest-cert-dir", "/srv/cert-dir",
 		"--dest-shared-blob-dir", "/srv/shared-blob-dir",
 		"--dest-daemon-host", "daemon-host.example.com",
@@ -64,7 +65,7 @@ func TestImageOptionsNewSystemContext(t *testing.T) {
 	require.NoError(t, err)
 	assert.Equal(t, &types.SystemContext{
 		RegistriesDirPath:                 "/srv/registries.d",
-		AuthFilePath:                      "/srv/authfile",
+		AuthFilePath:                      "/srv/dest-authfile",
 		ArchitectureChoice:                "overridden-arch",
 		OSChoice:                          "overridden-os",
 		OCISharedBlobDirPath:              "/srv/shared-blob-dir",
@@ -180,3 +181,47 @@ func TestImageDestOptionsNewSystemContext(t *testing.T) {
 	_, err = opts.newSystemContext()
 	assert.Error(t, err)
 }
+
+// since there is a shared authfile image option and a non-shared (prefixed) one, make sure the override logic
+// works correctly.
+func TestImageOptionsAuthfileOverride(t *testing.T) {
+
+	for _, testCase := range []struct {
+		flagPrefix           string
+		cmdFlags             []string
+		expectedAuthfilePath string
+	}{
+		// if there is no prefix, only authfile is allowed.
+		{"",
+			[]string{
+				"--authfile", "/srv/authfile",
+			}, "/srv/authfile"},
+		// if authfile and dest-authfile is provided, dest-authfile wins
+		{"dest-",
+			[]string{
+				"--authfile", "/srv/authfile",
+				"--dest-authfile", "/srv/dest-authfile",
+			}, "/srv/dest-authfile",
+		},
+		// if only the shared authfile is provided, authfile must be present in system context
+		{"dest-",
+			[]string{
+				"--authfile", "/srv/authfile",
+			}, "/srv/authfile",
+		},
+		// if only the dest authfile is provided, dest-authfile must be present in system context
+		{"dest-",
+			[]string{
+				"--dest-authfile", "/srv/dest-authfile",
+			}, "/srv/dest-authfile",
+		},
+	} {
+		opts := fakeImageOptions(t, testCase.flagPrefix, []string{}, testCase.cmdFlags)
+		res, err := opts.newSystemContext()
+		require.NoError(t, err)
+
+		assert.Equal(t, &types.SystemContext{
+			AuthFilePath: testCase.expectedAuthfilePath,
+		}, res)
+	}
+}

completions/bash/skopeo

@@ -37,6 +37,8 @@ _skopeo_supported_transports() {
 _skopeo_copy() {
     local options_with_args="
     --authfile
+    --src-authfile
+    --dest-authfile
     --format -f
     --sign-by
     --src-creds --screds

docs/skopeo-copy.1.md

@@ -28,6 +28,14 @@ the images in the list, and the list itself.
 Path of the authentication file. Default is ${XDG_RUNTIME\_DIR}/containers/auth.json, which is set using `podman login`.
 If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using `docker login`.
 
+**--src-authfile** _path_
+
+Path of the authentication file for the source registry. Uses path given by `--authfile`, if not provided.
+
+**--dest-authfile** _path_
+
+Path of the authentication file for the destination registry. Uses path given by `--authfile`, if not provided.
+
 **--format, -f** _manifest-type_ Manifest type (oci, v2s1, or v2s2) to use when saving image to directory using the 'dir:' transport (default is manifest type of source)
 
 **--quiet, -q** suppress output information when copying images

docs/skopeo-sync.1.md

@@ -37,6 +37,14 @@ name can be stored at _destination_.
 Path of the authentication file. Default is ${XDG\_RUNTIME\_DIR}/containers/auth.json, which is set using `podman login`.
 If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using `docker login`.
 
+**--src-authfile** _path_
+
+Path of the authentication file for the source registry. Uses path given by `--authfile`, if not provided.
+
+**--dest-authfile** _path_
+
+Path of the authentication file for the destination registry. Uses path given by `--authfile`, if not provided.
+
 **--src** _transport_ Transport for the source repository.
 
 **--dest** _transport_ Destination transport.