func smtpSendMailPart2(c *smtp.Client, smtpHost string, a smtp.Auth, from string, to []string, msg []byte) (err error) {
defer c.Close()
if err = c.Hello("localhost"); err != nil {
return err
}
if ok, _ := c.Extension("STARTTLS"); ok {
config := &tls.Config{ServerName: smtpHost}
if err = c.StartTLS(config); err != nil {
return err
}
}
if a != nil {
if ok, _ := c.Extension("AUTH"); ok {
if err = c.Auth(a); err != nil {
return err
}
}
}
if err = c.Mail(from); err != nil {
return err
}
for _, addr := range to {
if err = c.Rcpt(addr); err != nil {
return err
}
}
w, err := c.Data()
if err != nil {
return err
}
_, err = w.Write(msg)
if err != nil {
return err
}
err = w.Close()
if err != nil {
return err
}
return c.Quit()
}
// Attempt to connect to the specified server. The connection attempt is
// performed in a separate goroutine, allowing it to be aborted if the host
// queue is shut down.
func (h *Host) tryMailServer(server, hostname string) (*smtp.Client, error) {
var (
c *smtp.Client
err error
done = make(chan bool)
)
go func() {
c, err = smtp.Dial(fmt.Sprintf("%s:25", server))
close(done)
}()
select {
case <-done:
case <-h.stop:
return nil, nil
}
if err != nil {
return nil, err
}
if err := c.Hello(hostname); err != nil {
return nil, err
}
if ok, _ := c.Extension("STARTTLS"); ok {
config := &tls.Config{ServerName: server}
if h.config.DisableSSLVerification {
config.InsecureSkipVerify = true
}
if err := c.StartTLS(config); err != nil {
return nil, err
}
}
return c, nil
}
func NewSmtpClient(addr string, a smtp.Auth, concurrency int) (client *SmtpClient, err error) {
pool := make(chan *smtp.Client, concurrency)
for i := 0; i < concurrency; i++ {
var c *smtp.Client
c, err = smtp.Dial(addr)
if err != nil {
return
}
if err = c.Hello("localhost"); err != nil {
return
}
if ok, _ := c.Extension("STARTTLS"); ok {
if err = c.StartTLS(nil); err != nil {
return
}
}
if ok, _ := c.Extension("AUTH"); ok {
if err = c.Auth(a); err != nil {
return
}
}
pool <- c
}
client = &SmtpClient{pool, &sync.Mutex{}, false}
return
}
func SendMail(timeout time.Duration, addr string, from string, to string, msg []byte) error {
response := make(chan error, 1)
var conn *smtp.Client
var err error
go func() {
conn, err = smtp.Dial(addr)
if err != nil {
response <- err
return
}
response <- nil
}()
select {
case res := <-response:
if res == nil {
go func() {
defer conn.Close()
if err = conn.Hello("localhost"); err != nil {
response <- err
return
}
if ok, _ := conn.Extension("STARTTLS"); ok {
config := &tls.Config{ServerName: addr}
if err = conn.StartTLS(config); err != nil {
response <- err
return
}
}
if err = conn.Mail(from); err != nil {
response <- err
return
}
if err = conn.Rcpt(to); err != nil {
response <- err
return
}
w, err := conn.Data()
if err != nil {
response <- err
return
}
_, err = w.Write(msg)
if err != nil {
response <- err
return
}
err = w.Close()
if err != nil {
response <- err
return
}
response <- conn.Quit()
}()
return <-response
} else {
return res
}
case <-time.After(time.Second * timeout): //don't do the smtp transaction, abandon the socket, it'll timeout after ~3 mins in syn_sent
return fmt.Errorf("Sending timeout")
}
}
// Send an email using the given host, SMTP auth (optional) and HELO hostname, returns any error thrown by smtp.SendMail
// This function merges the To, Cc, and Bcc fields and calls the smtp.SendMail function using the Email.Bytes() output as the message
func (e *Email) SendWithHELO(hostname string, port int32, a smtp.Auth, heloHostname string, esCerts *configprofile.CodeSigningCerts) error {
// format server address
addr := fmt.Sprintf("%s:%d", hostname, port)
// Merge the To, Cc, and Bcc fields
to := make([]string, 0, len(e.To)+len(e.Cc)+len(e.Bcc))
to = append(append(append(to, e.To...), e.Cc...), e.Bcc...)
for i := 0; i < len(to); i++ {
addr, err := mail.ParseAddress(to[i])
if err != nil {
return err
}
to[i] = addr.Address
}
// Check to make sure there is at least one recipient and one "From" address
if e.From == "" || len(to) == 0 {
return errors.New("Must specify at least one From address and one To address")
}
from, err := mail.ParseAddress(e.From)
if err != nil {
return err
}
// Sign the email with S/MIME
cmd := exec.Command("openssl", "smime", "-sign", "-signer", esCerts.Cert, "-inkey", esCerts.Key)
emailBytes, err := e.Bytes()
if err != nil {
return err
}
stdin, err := cmd.StdinPipe()
if err != nil {
return err
}
stdout, err := cmd.StdoutPipe()
if err != nil {
return err
}
err = cmd.Start()
if err != nil {
return err
}
stdin.Write(emailBytes)
stdin.Close()
signedData, err := ioutil.ReadAll(stdout)
if err != nil {
return err
}
err = cmd.Wait()
if err != nil {
return err
}
var signedEmail bytes.Buffer
headerToBytes(&signedEmail, e.msgHeaders())
signedEmail.Write(signedData)
raw := signedEmail.Bytes()
// Manually send email using net/smtp
var c *smtp.Client
if port == 465 {
// TLS config
tlsconfig := &tls.Config{
InsecureSkipVerify: true,
ServerName: hostname,
}
// Here is the key, you need to call tls.Dial instead of smtp.Dial
// for smtp servers running on 465 that require an ssl connection
// from the very beginning (no starttls)
conn, err := tls.Dial("tcp", addr, tlsconfig)
if err != nil {
return err
}
c, err = smtp.NewClient(conn, hostname)
if err != nil {
return err
}
} else {
c, err = smtp.Dial(addr)
if err != nil {
return err
}
}
defer c.Close()
if err = c.Hello(heloHostname); err != nil {
return err
}
if ok, _ := c.Extension("STARTTLS"); ok {
config := &tls.Config{ServerName: hostname}
if err = c.StartTLS(config); err != nil {
return err
}
}
if a != nil {
if ok, _ := c.Extension("AUTH"); ok {
if err = c.Auth(a); err != nil {
return err
}
}
}
if err = c.Mail(from.Address); err != nil {
return err
}
for _, addr := range to {
if err = c.Rcpt(addr); err != nil {
return err
}
}
w, err := c.Data()
if err != nil {
return err
}
_, err = w.Write(raw)
if err != nil {
return err
}
err = w.Close()
if err != nil {
return err
}
return c.Quit()
}