feat(GODT-2610): re-use previous password when removing and adding back account.

internal/vault/password_archive.go

@@ -0,0 +1,46 @@
+// Copyright (c) 2023 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 (
+	"crypto/sha256"
+	"fmt"
+)
+
+// set archives the password for an email address, overwriting any existing archived value.
+func (p *PasswordArchive) set(emailAddress string, password []byte) {
+	if p.Archive == nil {
+		p.Archive = make(map[string][]byte)
+	}
+
+	p.Archive[emailHashString(emailAddress)] = password
+}
+
+// get retrieves the archived password for an email address, or nil if not found.
+func (p *PasswordArchive) get(emailAddress string) []byte {
+	if p.Archive == nil {
+		return nil
+	}
+
+	return p.Archive[emailHashString(emailAddress)]
+}
+
+// emailHashString returns a hash string for an email address as a hexadecimal string.
+func emailHashString(emailAddress string) string {
+	return fmt.Sprintf("%x", sha256.Sum256([]byte(emailAddress)))
+}