Merge pull request #2143 from slingamn/emailsending.1

fix #2142

default.yaml

@@ -409,6 +409,10 @@ accounts:
  sender: "[email protected]"
  require-tls: true
  helo-domain: "my.network" # defaults to server name if unset
+ # set to `tcp4` to force sending over IPv4, `tcp6` to force IPv6:
+ # protocol: "tcp4"
+ # set to force a specific source/local IPv4 or IPv6 address:
+ # local-address: "1.2.3.4"
  # options to enable DKIM signing of outgoing emails (recommended, but
  # requires creating a DNS entry for the public key):
  # dkim:

irc/email/email.go

@@ -75,6 +75,9 @@ type MailtoConfig struct {
  Sender string
  HeloDomain string `yaml:"helo-domain"`
  RequireTLS bool `yaml:"require-tls"`
+ Protocol string `yaml:"protocol"`
+ LocalAddress string `yaml:"local-address"`
+ localAddress net.Addr
  VerifyMessageSubject string `yaml:"verify-message-subject"`
  DKIM DKIMConfig
  MTAReal MTAConfig `yaml:"mta"`
@@ -159,6 +162,25 @@ func (config *MailtoConfig) Postprocess(heloDomain string) (err error) {
  }
  }
 
+ config.Protocol = strings.ToLower(config.Protocol)
+ if config.Protocol == "" {
+ config.Protocol = "tcp"
+ }
+ if !(config.Protocol == "tcp" || config.Protocol == "tcp4" || config.Protocol == "tcp6") {
+ return fmt.Errorf("Invalid protocol for email sending: `%s`", config.Protocol)
+ }
+
+ if config.LocalAddress != "" {
+ ipAddr := net.ParseIP(config.LocalAddress)
+ if ipAddr == nil {
+ return fmt.Errorf("Could not parse local-address for email sending: `%s`", config.LocalAddress)
+ }
+ config.localAddress = &net.TCPAddr{
+ IP: ipAddr,
+ Port: 0,
+ }
+ }
+
  if config.MTAConfig.Server != "" {
  // smarthost, nothing more to validate
  return nil
@@ -241,6 +263,6 @@ func SendMail(config MailtoConfig, recipient string, msg []byte) (err error) {
 
  return smtp.SendMail(
  addr, auth, config.HeloDomain, config.Sender, []string{recipient}, msg,
- config.RequireTLS, implicitTLS, config.Timeout,
+ config.RequireTLS, implicitTLS, config.Protocol, config.localAddress, config.Timeout,
  )
 }

irc/smtp/smtp.go

@@ -55,17 +55,18 @@ type Client struct {
 
 // Dial returns a new Client connected to an SMTP server at addr.
 // The addr must include a port, as in "mail.example.com:smtp".
-func Dial(addr string, timeout time.Duration, implicitTLS bool) (*Client, error) {
+func Dial(protocol, addr string, localAddress net.Addr, timeout time.Duration, implicitTLS bool) (*Client, error) {
  var conn net.Conn
  var err error
  dialer := net.Dialer{
- Timeout: timeout,
+ Timeout: timeout,
+ LocalAddr: localAddress,
  }
  start := time.Now()
  if !implicitTLS {
- conn, err = dialer.Dial("tcp", addr)
+ conn, err = dialer.Dial(protocol, addr)
  } else {
- conn, err = tls.DialWithDialer(&dialer, "tcp", addr, nil)
+ conn, err = tls.DialWithDialer(&dialer, protocol, addr, nil)
  }
  if err != nil {
  return nil, err
@@ -341,7 +342,7 @@ var testHookStartTLS func(*tls.Config) // nil, except for tests
 // functionality. Higher-level packages exist outside of the standard
 // library.
 // XXX: modified in Ergo to add `requireTLS`, `heloDomain`, and `timeout` arguments
-func SendMail(addr string, a Auth, heloDomain string, from string, to []string, msg []byte, requireTLS, implicitTLS bool, timeout time.Duration) error {
+func SendMail(addr string, a Auth, heloDomain string, from string, to []string, msg []byte, requireTLS, implicitTLS bool, protocol string, localAddress net.Addr, timeout time.Duration) error {
  if err := validateLine(from); err != nil {
  return err
  }
@@ -350,7 +351,7 @@ func SendMail(addr string, a Auth, heloDomain string, from string, to []string,
  return err
  }
  }
- c, err := Dial(addr, timeout, implicitTLS)
+ c, err := Dial(protocol, addr, localAddress, timeout, implicitTLS)
  if err != nil {
  return err
  }

traditional.yaml

@@ -381,6 +381,10 @@ accounts:
  sender: "[email protected]"
  require-tls: true
  helo-domain: "my.network" # defaults to server name if unset
+ # set to `tcp4` to force sending over IPv4, `tcp6` to force IPv6:
+ # protocol: "tcp4"
+ # set to force a specific source/local IPv4 or IPv6 address:
+ # local-address: "1.2.3.4"
  # options to enable DKIM signing of outgoing emails (recommended, but
  # requires creating a DNS entry for the public key):
  # dkim: