Merge pull request #19 from rymdport/secret

WIP: Implement Secret interface

Author: Jacalz

README.md

@@ -76,7 +76,7 @@ The list below contains all of the portal interfaces available within the projec
 - [x] Request
 - [ ] ScreenCast
 - [x] Screenshot
-- [ ] Secret
+- [x] Secret
 - [x] Session
 - [x] Settings
 - [x] Trash

secret/retrieve.go

@@ -0,0 +1,60 @@
+package secret
+
+import (
+	"fmt"
+
+	"github.com/godbus/dbus/v5"
+	"github.com/rymdport/portal/internal/apis"
+	"github.com/rymdport/portal/internal/convert"
+	"github.com/rymdport/portal/internal/request"
+)
+
+const retrieveSecretCallName = interfaceName + ".RetrieveSecret"
+
+// RetrieveOptions contains options for the RetrieveSecret function call.
+type RetrieveOptions struct {
+	HandleToken string // A string that will be used as the last element of the handle. Must be a valid object path element.
+	Token       string // An opaque string returned by a previous org.freedesktop.portal.Secret.RetrieveSecret call.
+}
+
+// RetrieveSecret retrieves a master secret for a sandboxed application.
+// The master secret is unique per application and does not change as
+// long as the application is installed (once it has been created).
+// In a typical backend implementation, it is stored in the user’s keyring,
+// under the application ID as a key.
+// The parameter fd is a writable file descriptor for transporting the secret.
+//
+// The portal may return an additional identifier associated with the secret in the results.
+// In the next call of this method, the application shall provide a token element in options.
+func RetrieveSecret(fd uintptr, options *RetrieveOptions) (string, error) {
+	data := map[string]dbus.Variant{}
+	if options != nil {
+		if options.HandleToken != "" {
+			data["handle_token"] = convert.FromString(options.HandleToken)
+		}
+		if options.Token != "" {
+			data["token"] = convert.FromString(options.Token)
+		}
+	}
+
+	result, err := apis.Call(retrieveSecretCallName, dbus.UnixFD(fd), data)
+	if err != nil {
+		return "", err
+	}
+
+	path := result.(dbus.ObjectPath)
+	status, results, err := request.OnSignalResponse(path)
+	if err != nil {
+		return "", err
+	} else if status > request.Success {
+		return "", nil
+	}
+
+	if token, ok := results["token"]; ok {
+		return token.Value().(string), nil
+	} else if len(results) != 0 {
+		fmt.Println("Please contribute this information to rymdport/portal: ", results)
+	}
+
+	return "", nil
+}

secret/secret.go

@@ -0,0 +1,4 @@
+// Package secret allows sandboxed applications to retrieve a per-application secret. The secret can then be used for encrypting confidential data inside the sandbox.
+package secret
+
+const interfaceName = "org.freedesktop.portal.Secret"