Files
mattermost/utils/mail.go
2018-06-14 19:27:21 +02:00

300 lines
9.4 KiB
Go

// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See License.txt for license information.
package utils
import (
"crypto/tls"
"errors"
"fmt"
"io"
"mime"
"net"
"net/mail"
"net/smtp"
"time"
"gopkg.in/gomail.v2"
"net/http"
"github.com/jaytaylor/html2text"
"github.com/mattermost/mattermost-server/mlog"
"github.com/mattermost/mattermost-server/model"
)
func encodeRFC2047Word(s string) string {
return mime.BEncoding.Encode("utf-8", s)
}
type SmtpConnectionInfo struct {
SmtpUsername string
SmtpPassword string
SmtpServerName string
SmtpServerHost string
SmtpPort string
SkipCertVerification bool
ConnectionSecurity string
Auth bool
}
type authChooser struct {
smtp.Auth
connectionInfo *SmtpConnectionInfo
}
func (a *authChooser) Start(server *smtp.ServerInfo) (string, []byte, error) {
smtpAddress := a.connectionInfo.SmtpServerName + ":" + a.connectionInfo.SmtpPort
a.Auth = LoginAuth(a.connectionInfo.SmtpUsername, a.connectionInfo.SmtpPassword, smtpAddress)
for _, method := range server.Auth {
if method == "PLAIN" {
a.Auth = smtp.PlainAuth("", a.connectionInfo.SmtpUsername, a.connectionInfo.SmtpPassword, a.connectionInfo.SmtpServerName+":"+a.connectionInfo.SmtpPort)
break
}
}
return a.Auth.Start(server)
}
type loginAuth struct {
username, password, host string
}
func LoginAuth(username, password, host string) smtp.Auth {
return &loginAuth{username, password, host}
}
func (a *loginAuth) Start(server *smtp.ServerInfo) (string, []byte, error) {
if !server.TLS {
return "", nil, errors.New("unencrypted connection")
}
if server.Name != a.host {
return "", nil, errors.New("wrong host name")
}
return "LOGIN", []byte{}, nil
}
func (a *loginAuth) Next(fromServer []byte, more bool) ([]byte, error) {
if more {
switch string(fromServer) {
case "Username:":
return []byte(a.username), nil
case "Password:":
return []byte(a.password), nil
default:
return nil, errors.New("Unknown fromServer")
}
}
return nil, nil
}
func ConnectToSMTPServerAdvanced(connectionInfo *SmtpConnectionInfo) (net.Conn, *model.AppError) {
var conn net.Conn
var err error
smtpAddress := connectionInfo.SmtpServerHost + ":" + connectionInfo.SmtpPort
if connectionInfo.ConnectionSecurity == model.CONN_SECURITY_TLS {
tlsconfig := &tls.Config{
InsecureSkipVerify: connectionInfo.SkipCertVerification,
ServerName: connectionInfo.SmtpServerName,
}
conn, err = tls.Dial("tcp", smtpAddress, tlsconfig)
if err != nil {
return nil, model.NewAppError("SendMail", "utils.mail.connect_smtp.open_tls.app_error", nil, err.Error(), http.StatusInternalServerError)
}
} else {
conn, err = net.Dial("tcp", smtpAddress)
if err != nil {
return nil, model.NewAppError("SendMail", "utils.mail.connect_smtp.open.app_error", nil, err.Error(), http.StatusInternalServerError)
}
}
return conn, nil
}
func ConnectToSMTPServer(config *model.Config) (net.Conn, *model.AppError) {
return ConnectToSMTPServerAdvanced(
&SmtpConnectionInfo{
ConnectionSecurity: config.EmailSettings.ConnectionSecurity,
SkipCertVerification: *config.EmailSettings.SkipServerCertificateVerification,
SmtpServerName: config.EmailSettings.SMTPServer,
SmtpServerHost: config.EmailSettings.SMTPServer,
SmtpPort: config.EmailSettings.SMTPPort,
},
)
}
func NewSMTPClientAdvanced(conn net.Conn, hostname string, connectionInfo *SmtpConnectionInfo) (*smtp.Client, *model.AppError) {
c, err := smtp.NewClient(conn, connectionInfo.SmtpServerName+":"+connectionInfo.SmtpPort)
if err != nil {
mlog.Error(fmt.Sprintf("Failed to open a connection to SMTP server %v", err))
return nil, model.NewAppError("SendMail", "utils.mail.connect_smtp.open_tls.app_error", nil, err.Error(), http.StatusInternalServerError)
}
if hostname != "" {
err := c.Hello(hostname)
if err != nil {
mlog.Error(fmt.Sprintf("Failed to to set the HELO to SMTP server %v", err))
return nil, model.NewAppError("SendMail", "utils.mail.connect_smtp.helo.app_error", nil, err.Error(), http.StatusInternalServerError)
}
}
if connectionInfo.ConnectionSecurity == model.CONN_SECURITY_STARTTLS {
tlsconfig := &tls.Config{
InsecureSkipVerify: connectionInfo.SkipCertVerification,
ServerName: connectionInfo.SmtpServerName,
}
c.StartTLS(tlsconfig)
}
if connectionInfo.Auth {
if err = c.Auth(&authChooser{connectionInfo: connectionInfo}); err != nil {
return nil, model.NewAppError("SendMail", "utils.mail.new_client.auth.app_error", nil, err.Error(), http.StatusInternalServerError)
}
}
return c, nil
}
func NewSMTPClient(conn net.Conn, config *model.Config) (*smtp.Client, *model.AppError) {
return NewSMTPClientAdvanced(
conn,
GetHostnameFromSiteURL(*config.ServiceSettings.SiteURL),
&SmtpConnectionInfo{
ConnectionSecurity: config.EmailSettings.ConnectionSecurity,
SkipCertVerification: *config.EmailSettings.SkipServerCertificateVerification,
SmtpServerName: config.EmailSettings.SMTPServer,
SmtpServerHost: config.EmailSettings.SMTPServer,
SmtpPort: config.EmailSettings.SMTPPort,
Auth: *config.EmailSettings.EnableSMTPAuth,
SmtpUsername: config.EmailSettings.SMTPUsername,
SmtpPassword: config.EmailSettings.SMTPPassword,
},
)
}
func TestConnection(config *model.Config) {
if !config.EmailSettings.SendEmailNotifications {
return
}
conn, err1 := ConnectToSMTPServer(config)
if err1 != nil {
mlog.Error(fmt.Sprintf("SMTP server settings do not appear to be configured properly err=%v details=%v", T(err1.Message), err1.DetailedError))
return
}
defer conn.Close()
c, err2 := NewSMTPClient(conn, config)
if err2 != nil {
mlog.Error(fmt.Sprintf("SMTP server settings do not appear to be configured properly err=%v details=%v", T(err2.Message), err2.DetailedError))
return
}
defer c.Quit()
defer c.Close()
}
func SendMailUsingConfig(to, subject, htmlBody string, config *model.Config, enableComplianceFeatures bool) *model.AppError {
fromMail := mail.Address{Name: config.EmailSettings.FeedbackName, Address: config.EmailSettings.FeedbackEmail}
return SendMailUsingConfigAdvanced(to, to, fromMail, subject, htmlBody, nil, nil, config, enableComplianceFeatures)
}
// allows for sending an email with attachments and differing MIME/SMTP recipients
func SendMailUsingConfigAdvanced(mimeTo, smtpTo string, from mail.Address, subject, htmlBody string, attachments []*model.FileInfo, mimeHeaders map[string]string, config *model.Config, enableComplianceFeatures bool) *model.AppError {
if !config.EmailSettings.SendEmailNotifications || len(config.EmailSettings.SMTPServer) == 0 {
return nil
}
conn, err := ConnectToSMTPServer(config)
if err != nil {
return err
}
defer conn.Close()
c, err := NewSMTPClient(conn, config)
if err != nil {
return err
}
defer c.Quit()
defer c.Close()
fileBackend, err := NewFileBackend(&config.FileSettings, enableComplianceFeatures)
if err != nil {
return err
}
return SendMail(c, mimeTo, smtpTo, from, subject, htmlBody, attachments, mimeHeaders, fileBackend, time.Now())
}
func SendMail(c *smtp.Client, mimeTo, smtpTo string, from mail.Address, subject, htmlBody string, attachments []*model.FileInfo, mimeHeaders map[string]string, fileBackend FileBackend, date time.Time) *model.AppError {
mlog.Debug(fmt.Sprintf("sending mail to %v with subject of '%v'", smtpTo, subject))
htmlMessage := "\r\n<html><body>" + htmlBody + "</body></html>"
txtBody, err := html2text.FromString(htmlBody)
if err != nil {
mlog.Warn(fmt.Sprint(err))
txtBody = ""
}
headers := map[string][]string{
"From": {from.String()},
"To": {mimeTo},
"Subject": {encodeRFC2047Word(subject)},
"Content-Transfer-Encoding": {"8bit"},
"Auto-Submitted": {"auto-generated"},
"Precedence": {"bulk"},
}
for k, v := range mimeHeaders {
headers[k] = []string{encodeRFC2047Word(v)}
}
m := gomail.NewMessage(gomail.SetCharset("UTF-8"))
m.SetHeaders(headers)
m.SetDateHeader("Date", date)
m.SetBody("text/plain", txtBody)
m.AddAlternative("text/html", htmlMessage)
if attachments != nil {
for _, fileInfo := range attachments {
bytes, err := fileBackend.ReadFile(fileInfo.Path)
if err != nil {
return err
}
m.Attach(fileInfo.Name, gomail.SetCopyFunc(func(writer io.Writer) error {
if _, err := writer.Write(bytes); err != nil {
return model.NewAppError("SendMail", "utils.mail.sendMail.attachments.write_error", nil, err.Error(), http.StatusInternalServerError)
}
return nil
}))
}
}
if err := c.Mail(from.Address); err != nil {
return model.NewAppError("SendMail", "utils.mail.send_mail.from_address.app_error", nil, err.Error(), http.StatusInternalServerError)
}
if err := c.Rcpt(smtpTo); err != nil {
return model.NewAppError("SendMail", "utils.mail.send_mail.to_address.app_error", nil, err.Error(), http.StatusInternalServerError)
}
w, err := c.Data()
if err != nil {
return model.NewAppError("SendMail", "utils.mail.send_mail.msg_data.app_error", nil, err.Error(), http.StatusInternalServerError)
}
_, err = m.WriteTo(w)
if err != nil {
return model.NewAppError("SendMail", "utils.mail.send_mail.msg.app_error", nil, err.Error(), http.StatusInternalServerError)
}
err = w.Close()
if err != nil {
return model.NewAppError("SendMail", "utils.mail.send_mail.close.app_error", nil, err.Error(), http.StatusInternalServerError)
}
return nil
}