forgejo/services/auth/source/smtp/auth.go
zeripath e29e163737
Improve SMTP authentication and Fix user creation bugs (#16612)
* Improve SMTP authentication, Fix user creation bugs and add LDAP cert/key options

This PR has two parts:

Improvements for SMTP authentication:

* Default to use SMTPS if port is 465, and allow setting of force SMTPS.
* Always use STARTTLS if available
* Provide CRAM-MD5 mechanism
* Add options for HELO hostname disabling
* Add options for providing certificates and keys
* Handle application specific password response as a failed user login
instead of as a 500.

Close #16104

Fix creation of new users:

* A bug was introduced when allowing users to change usernames which
prevents the creation of external users.
* The LoginSource refactor also broke this page.

Close #16104

Signed-off-by: Andrew Thornton <art27@cantab.net>
2021-08-11 21:42:58 +01:00

105 lines
2.5 KiB
Go

// Copyright 2021 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package smtp
import (
"crypto/tls"
"fmt"
"net"
"net/smtp"
"os"
"strconv"
"code.gitea.io/gitea/models"
)
// _________ __________________________
// / _____/ / \__ ___/\______ \
// \_____ \ / \ / \| | | ___/
// / \/ Y \ | | |
// /_______ /\____|__ /____| |____|
// \/ \/
type loginAuthenticator struct {
username, password string
}
func (auth *loginAuthenticator) Start(server *smtp.ServerInfo) (string, []byte, error) {
return "LOGIN", []byte(auth.username), nil
}
func (auth *loginAuthenticator) Next(fromServer []byte, more bool) ([]byte, error) {
if more {
switch string(fromServer) {
case "Username:":
return []byte(auth.username), nil
case "Password:":
return []byte(auth.password), nil
}
}
return nil, nil
}
// SMTP authentication type names.
const (
PlainAuthentication = "PLAIN"
LoginAuthentication = "LOGIN"
CRAMMD5Authentication = "CRAM-MD5"
)
// Authenticators contains available SMTP authentication type names.
var Authenticators = []string{PlainAuthentication, LoginAuthentication, CRAMMD5Authentication}
// Authenticate performs an SMTP authentication.
func Authenticate(a smtp.Auth, source *Source) error {
tlsConfig := &tls.Config{
InsecureSkipVerify: source.SkipVerify,
ServerName: source.Host,
}
conn, err := net.Dial("tcp", net.JoinHostPort(source.Host, strconv.Itoa(source.Port)))
if err != nil {
return err
}
defer conn.Close()
if source.UseTLS() {
conn = tls.Client(conn, tlsConfig)
}
client, err := smtp.NewClient(conn, source.Host)
if err != nil {
return fmt.Errorf("failed to create NewClient: %w", err)
}
defer client.Close()
if !source.DisableHelo {
hostname := source.HeloHostname
if len(hostname) == 0 {
hostname, err = os.Hostname()
if err != nil {
return fmt.Errorf("failed to find Hostname: %w", err)
}
}
if err = client.Hello(hostname); err != nil {
return fmt.Errorf("failed to send Helo: %w", err)
}
}
// If not using SMTPS, always use STARTTLS if available
hasStartTLS, _ := client.Extension("STARTTLS")
if !source.UseTLS() && hasStartTLS {
if err = client.StartTLS(tlsConfig); err != nil {
return fmt.Errorf("failed to start StartTLS: %v", err)
}
}
if ok, _ := client.Extension("AUTH"); ok {
return client.Auth(a)
}
return models.ErrUnsupportedLoginType
}