We build too many walls and not enough bridges

internal/bridge/credentials/credentials.go

@@ -0,0 +1,137 @@
+// Copyright (c) 2020 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail 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.
+//
+// ProtonMail 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 ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+// Package credentials implements our struct stored in keychain.
+// Store struct is kind of like a database client.
+// Credentials struct is kind of like one record from the database.
+package credentials
+
+import (
+	"crypto/subtle"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/ProtonMail/proton-bridge/pkg/config"
+	"github.com/sirupsen/logrus"
+)
+
+const sep = "\x00"
+
+var (
+	log = config.GetLogEntry("bridge") //nolint[gochecknoglobals]
+
+	ErrWrongFormat = errors.New("backend/creds: malformed password")
+)
+
+type Credentials struct {
+	UserID, // Do not marshal; used as a key.
+	Name,
+	Emails,
+	APIToken,
+	MailboxPassword,
+	BridgePassword,
+	Version string
+	Timestamp int64
+	IsHidden, // Deprecated.
+	IsCombinedAddressMode bool
+}
+
+func (s *Credentials) Marshal() string {
+	items := []string{
+		s.Name,            // 0
+		s.Emails,          // 1
+		s.APIToken,        // 2
+		s.MailboxPassword, // 3
+		s.BridgePassword,  // 4
+		s.Version,         // 5
+		"",                // 6
+		"",                // 7
+		"",                // 8
+	}
+
+	items[6] = fmt.Sprint(s.Timestamp)
+
+	if s.IsHidden {
+		items[7] = "1"
+	}
+
+	if s.IsCombinedAddressMode {
+		items[8] = "1"
+	}
+
+	str := strings.Join(items, sep)
+	return base64.StdEncoding.EncodeToString([]byte(str))
+}
+
+func (s *Credentials) Unmarshal(secret string) error {
+	b, err := base64.StdEncoding.DecodeString(secret)
+	if err != nil {
+		return err
+	}
+	items := strings.Split(string(b), sep)
+
+	if len(items) != 9 {
+		return ErrWrongFormat
+	}
+
+	s.Name = items[0]
+	s.Emails = items[1]
+	s.APIToken = items[2]
+	s.MailboxPassword = items[3]
+	s.BridgePassword = items[4]
+	s.Version = items[5]
+	if _, err = fmt.Sscan(items[6], &s.Timestamp); err != nil {
+		s.Timestamp = 0
+	}
+	if s.IsHidden = false; items[7] == "1" {
+		s.IsHidden = true
+	}
+	if s.IsCombinedAddressMode = false; items[8] == "1" {
+		s.IsCombinedAddressMode = true
+	}
+	return nil
+}
+
+func (s *Credentials) SetEmailList(list []string) {
+	s.Emails = strings.Join(list, ";")
+}
+
+func (s *Credentials) EmailList() []string {
+	return strings.Split(s.Emails, ";")
+}
+
+func (s *Credentials) CheckPassword(password string) error {
+	if subtle.ConstantTimeCompare([]byte(s.BridgePassword), []byte(password)) != 1 {
+		log.WithFields(logrus.Fields{
+			"userID": s.UserID,
+		}).Debug("Incorrect bridge password")
+
+		return fmt.Errorf("backend/credentials: incorrect password")
+	}
+	return nil
+}
+
+func (s *Credentials) Logout() {
+	s.APIToken = ""
+	s.MailboxPassword = ""
+}
+
+func (s *Credentials) IsConnected() bool {
+	return s.APIToken != "" && s.MailboxPassword != ""
+}