feat(BRIDGE-116): add command-line switches to enable/disable keychain check on macOS.

internal/vault/keychain_settings.go

@@ -0,0 +1,74 @@
+// Copyright (c) 2024 Proton AG
+//
+// This file is part of Proton Mail Bridge.
+//
+// Proton Mail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail Bridge. If not, see <https://www.gnu.org/licenses/>.
+
+package vault
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/sirupsen/logrus"
+)
+
+const keychainSettingsFileName = "keychain.json"
+
+// KeychainSettings holds settings related to the keychain. It is serialized in the vault directory.
+type KeychainSettings struct {
+	Helper      string // The helper used for keychain.
+	DisableTest bool   // Is the keychain test on startup disabled?
+}
+
+// LoadKeychainSettings load keychain settings from the vaultDir folder, or returns a default one if the file
+// does not exists or is invalid.
+func LoadKeychainSettings(vaultDir string) (KeychainSettings, error) {
+	path := filepath.Join(vaultDir, keychainSettingsFileName)
+	bytes, err := os.ReadFile(path) //nolint:gosec
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			logrus.
+				WithFields(logrus.Fields{"pkg": "vault", "path": path}).
+				Trace("Keychain settings file does not exists, default values will be used")
+			return KeychainSettings{}, nil
+		}
+		return KeychainSettings{}, err
+	}
+
+	var result KeychainSettings
+	if err := json.Unmarshal(bytes, &result); err != nil {
+		return KeychainSettings{}, fmt.Errorf("keychain settings file is invalid settings: %w", err)
+	}
+
+	return result, nil
+}
+
+// Save saves the keychain settings in a file in the vaultDir folder.
+func (k KeychainSettings) Save(vaultDir string) error {
+	bytes, err := json.MarshalIndent(k, "", "  ")
+	if err != nil {
+		return err
+	}
+
+	if err = os.MkdirAll(vaultDir, 0o700); err != nil {
+		return err
+	}
+
+	path := filepath.Join(vaultDir, keychainSettingsFileName)
+	return os.WriteFile(path, bytes, 0o600)
+}