smtp.go

   1 package main
   2
   3 import (
   4         "crypto/tls"
   5         "fmt"
   6         "net"
   7         "net/mail"
   8         "os"
   9         "path"
  10         "strings"
  11
  12         "src.bluestatic.org/mailpopbox/smtp"
  13 )
  14
  15 func runSMTPServer(config Config) <-chan error {
  16         server := smtpServer{
  17                 config: config,
  18                 rc:     make(chan error),
  19         }
  20         go server.run()
  21         return server.rc
  22 }
  23
  24 type smtpServer struct {
  25         config    Config
  26         tlsConfig *tls.Config
  27
  28         rc chan error
  29 }
  30
  31 func (server *smtpServer) run() {
  32         var err error
  33         server.tlsConfig, err = server.config.GetTLSConfig()
  34         if err != nil {
  35                 server.rc <- err
  36         }
  37
  38         l, err := net.Listen("tcp", fmt.Sprintf(":%d", server.config.SMTPPort))
  39         if err != nil {
  40                 server.rc <- err
  41                 return
  42         }
  43
  44         for {
  45                 conn, err := l.Accept()
  46                 if err != nil {
  47                         server.rc <- err
  48                         return
  49                 }
  50
  51                 go smtp.AcceptConnection(conn, server)
  52         }
  53 }
  54
  55 func (server *smtpServer) Name() string {
  56         return server.config.Hostname
  57 }
  58
  59 func (server *smtpServer) TLSConfig() *tls.Config {
  60         return server.tlsConfig
  61 }
  62
  63 func (server *smtpServer) VerifyAddress(addr mail.Address) smtp.ReplyLine {
  64         if server.maildropForAddress(addr) == "" {
  65                 return smtp.ReplyBadMailbox
  66         }
  67         return smtp.ReplyOK
  68 }
  69
  70 func (server *smtpServer) OnEHLO() *smtp.ReplyLine {
  71         return nil
  72 }
  73
  74 func (server *smtpServer) OnMessageDelivered(en smtp.Envelope) *smtp.ReplyLine {
  75         maildrop := server.maildropForAddress(en.RcptTo[0])
  76         if maildrop == "" {
  77                 // TODO: log error
  78                 return &smtp.ReplyBadMailbox
  79         }
  80
  81         f, err := os.Create(path.Join(maildrop, en.ID+".msg"))
  82         if err != nil {
  83                 // TODO: log error
  84                 return &smtp.ReplyBadMailbox
  85         }
  86
  87         smtp.WriteEnvelopeForDelivery(f, en)
  88         f.Close()
  89         return nil
  90 }
  91
  92 func (server *smtpServer) maildropForAddress(addr mail.Address) string {
  93         domainIdx := strings.LastIndex(addr.Address, "@")
  94         if domainIdx == -1 {
  95                 return ""
  96         }
  97
  98         domain := addr.Address[domainIdx+1:]
  99
 100         for _, s := range server.config.Servers {
 101                 if domain == s.Domain {
 102                         return s.MaildropPath
 103                 }
 104         }
 105
 106         return ""
 107 }