Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Auto detect authentication type #80

Merged
merged 1 commit into from
Jul 4, 2023
Merged

Auto detect authentication type #80

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
93 changes: 63 additions & 30 deletions email.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@ import (
"net/mail"
"net/textproto"
"strconv"
"strings"
"time"

"github.com/toorop/go-dkim"
Expand Down Expand Up @@ -134,8 +135,22 @@ const (
AuthCRAMMD5
// AuthNone for SMTP servers without authentication
AuthNone
AuthAuto
)

func (at AuthType) String() string {
switch at {
case 0:
return "PLAIN"
case 1:
return "LOGIN"
case 2:
return "CRAM-MD5"
default:
return ""
}
}

// NewMSG creates a new email. It uses UTF-8 by default. All charsets: http://webcheatsheet.com/HTML/character_sets_list.php
func NewMSG() *Email {
email := &Email{
Expand All @@ -152,7 +167,7 @@ func NewMSG() *Email {
// NewSMTPClient returns the client for send email
func NewSMTPClient() *SMTPServer {
server := &SMTPServer{
Authentication: AuthPlain,
Authentication: AuthAuto,
Encryption: EncryptionNone,
ConnectTimeout: 10 * time.Second,
SendTimeout: 10 * time.Second,
Expand Down Expand Up @@ -717,7 +732,7 @@ func dial(host string, port string, encryption Encryption, config *tls.Config) (

// smtpConnect connects to the smtp server and starts TLS and passes auth
// if necessary
func smtpConnect(host, port, helo string, a auth, at AuthType, encryption Encryption, config *tls.Config) (*smtpClient, error) {
func smtpConnect(host, port, helo string, encryption Encryption, config *tls.Config) (*smtpClient, error) {
// connect to the mail server
c, err := dial(host, port, encryption, config)

Expand Down Expand Up @@ -746,42 +761,60 @@ func smtpConnect(host, port, helo string, a auth, at AuthType, encryption Encryp
}
}

// only pass authentication if defined
if at != AuthNone {
// pass the authentication if necessary
if a != nil {
if ok, _ := c.extension("AUTH"); ok {
if err = c.authenticate(a); err != nil {
c.close()
return nil, fmt.Errorf("Mail Error on Auth: %w", err)
}
}
}
}

return c, nil
}

// Connect returns the smtp client
func (server *SMTPServer) Connect() (*SMTPClient, error) {

var a auth

switch server.Authentication {
case AuthPlain:
func (server *SMTPServer) getAuth(a string) (auth, error) {
var afn auth
switch {
case strings.Contains(a, AuthPlain.String()):
if server.Username != "" || server.Password != "" {
a = plainAuthfn("", server.Username, server.Password, server.Host)
afn = plainAuthfn("", server.Username, server.Password, server.Host)
}
case AuthLogin:
case strings.Contains(a, AuthLogin.String()):
if server.Username != "" || server.Password != "" {
a = loginAuthfn("", server.Username, server.Password, server.Host)
afn = loginAuthfn("", server.Username, server.Password, server.Host)
}
case AuthCRAMMD5:
case strings.Contains(a, AuthCRAMMD5.String()):
if server.Username != "" || server.Password != "" {
a = cramMD5Authfn(server.Username, server.Password)
afn = cramMD5Authfn(server.Username, server.Password)
}
default:
return nil, fmt.Errorf("Mail Error on determining auth type, %s is not supported", a)
}
return afn, nil
}

func (server *SMTPServer) validateAuth(c *smtpClient) error {
var err error
var afn auth
switch {
case server.Authentication == AuthNone || server.Username == "":
return nil
case server.Authentication != AuthAuto:
afn, err = server.getAuth(server.Authentication.String())
if err != nil {
return err
}
}
if ok, a := c.extension("AUTH"); ok {
// Determine Auth type automatically from extension
if afn == nil {
afn, err = server.getAuth(a)
if err != nil {
return err
}
}
if err = c.authenticate(afn); err != nil {
c.close()
return fmt.Errorf("Mail Error on Auth: %w", err)
}
}
return nil
}

// Connect returns the smtp client
func (server *SMTPServer) Connect() (*SMTPClient, error) {
var smtpConnectChannel chan error
var c *smtpClient
var err error
Expand All @@ -795,7 +828,7 @@ func (server *SMTPServer) Connect() (*SMTPClient, error) {
if server.ConnectTimeout != 0 {
smtpConnectChannel = make(chan error, 2)
go func() {
c, err = smtpConnect(server.Host, fmt.Sprintf("%d", server.Port), server.Helo, a, server.Authentication, server.Encryption, tlsConfig)
c, err = smtpConnect(server.Host, fmt.Sprintf("%d", server.Port), server.Helo, server.Encryption, tlsConfig)
// send the result
smtpConnectChannel <- err
}()
Expand All @@ -810,7 +843,7 @@ func (server *SMTPServer) Connect() (*SMTPClient, error) {
}
} else {
// no ConnectTimeout, just fire the connect
c, err = smtpConnect(server.Host, fmt.Sprintf("%d", server.Port), server.Helo, a, server.Authentication, server.Encryption, tlsConfig)
c, err = smtpConnect(server.Host, fmt.Sprintf("%d", server.Port), server.Helo, server.Encryption, tlsConfig)
if err != nil {
return nil, err
}
Expand All @@ -820,7 +853,7 @@ func (server *SMTPServer) Connect() (*SMTPClient, error) {
Client: c,
KeepAlive: server.KeepAlive,
SendTimeout: server.SendTimeout,
}, nil
}, server.validateAuth(c)
}

// Reset send RSET command to smtp client
Expand Down