mirror of
https://github.com/ProtonMail/proton-bridge.git
synced 2025-12-10 20:56:51 +00:00
31fb878bbd
go-smtp now comes with out of the box support for SASL PLAIN but it still requires manual implementation of SASL LOGIN (deprecated).
117 lines
3.7 KiB
Go
117 lines
3.7 KiB
Go
// Copyright (c) 2022 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 bridge
|
|
|
|
import (
|
|
"context"
|
|
"crypto/tls"
|
|
"fmt"
|
|
|
|
"github.com/ProtonMail/proton-bridge/v2/internal/logging"
|
|
|
|
"github.com/ProtonMail/proton-bridge/v2/internal/constants"
|
|
"github.com/emersion/go-sasl"
|
|
"github.com/emersion/go-smtp"
|
|
"github.com/sirupsen/logrus"
|
|
)
|
|
|
|
func (bridge *Bridge) serveSMTP() error {
|
|
logrus.Info("Starting SMTP server")
|
|
|
|
smtpListener, err := newListener(bridge.vault.GetSMTPPort(), bridge.vault.GetSMTPSSL(), bridge.tlsConfig)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to create SMTP listener: %w", err)
|
|
}
|
|
|
|
bridge.smtpListener = smtpListener
|
|
|
|
bridge.tasks.Once(func(context.Context) {
|
|
if err := bridge.smtpServer.Serve(smtpListener); err != nil {
|
|
logrus.WithError(err).Info("SMTP server stopped")
|
|
}
|
|
})
|
|
|
|
if err := bridge.vault.SetSMTPPort(getPort(smtpListener.Addr())); err != nil {
|
|
return fmt.Errorf("failed to set IMAP port: %w", err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (bridge *Bridge) restartSMTP() error {
|
|
logrus.Info("Restarting SMTP server")
|
|
|
|
if err := bridge.closeSMTP(); err != nil {
|
|
return fmt.Errorf("failed to close SMTP: %w", err)
|
|
}
|
|
|
|
bridge.smtpServer = newSMTPServer(bridge, bridge.tlsConfig, bridge.logSMTP)
|
|
|
|
return bridge.serveSMTP()
|
|
}
|
|
|
|
// We close the listener ourselves even though it's also closed by smtpServer.Close().
|
|
// This is because smtpServer.Serve() is called in a separate goroutine and might be executed
|
|
// after we've already closed the server. However, go-smtp has a bug; it blocks on the listener
|
|
// even after the server has been closed. So we close the listener ourselves to unblock it.
|
|
func (bridge *Bridge) closeSMTP() error {
|
|
logrus.Info("Closing SMTP server")
|
|
|
|
if bridge.smtpListener != nil {
|
|
if err := bridge.smtpListener.Close(); err != nil {
|
|
return fmt.Errorf("failed to close SMTP listener: %w", err)
|
|
}
|
|
}
|
|
|
|
if err := bridge.smtpServer.Close(); err != nil {
|
|
logrus.WithError(err).Debug("Failed to close SMTP server (expected -- we close the listener ourselves)")
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func newSMTPServer(bridge *Bridge, tlsConfig *tls.Config, logSMTP bool) *smtp.Server {
|
|
logrus.WithField("logSMTP", logSMTP).Info("Creating SMTP server")
|
|
|
|
smtpServer := smtp.NewServer(&smtpBackend{Bridge: bridge})
|
|
|
|
smtpServer.TLSConfig = tlsConfig
|
|
smtpServer.Domain = constants.Host
|
|
smtpServer.AllowInsecureAuth = true
|
|
smtpServer.MaxLineLength = 1 << 16
|
|
smtpServer.ErrorLog = logging.NewSMTPLogger()
|
|
|
|
// go-smtp suppors SASL PLAIN but not LOGIN. We need to add LOGIN support ourselves.
|
|
smtpServer.EnableAuth(sasl.Login, func(conn *smtp.Conn) sasl.Server {
|
|
return sasl.NewLoginServer(func(username, password string) error {
|
|
return conn.Session().AuthPlain(username, password)
|
|
})
|
|
})
|
|
|
|
if logSMTP {
|
|
log := logrus.WithField("protocol", "SMTP")
|
|
log.Warning("================================================")
|
|
log.Warning("THIS LOG WILL CONTAIN **DECRYPTED** MESSAGE DATA")
|
|
log.Warning("================================================")
|
|
|
|
smtpServer.Debug = logging.NewSMTPDebugLogger()
|
|
}
|
|
|
|
return smtpServer
|
|
}
|