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         rc     chan error
  27 }
  28
  29 func (server *smtpServer) run() {
  30         l, err := net.Listen("tcp", fmt.Sprintf(":%d", server.config.SMTPPort))
  31         if err != nil {
  32                 server.rc <- err
  33                 return
  34         }
  35
  36         for {
  37                 conn, err := l.Accept()
  38                 if err != nil {
  39                         server.rc <- err
  40                         return
  41                 }
  42
  43                 go smtp.AcceptConnection(conn, server)
  44         }
  45 }
  46
  47 func (server *smtpServer) Name() string {
  48         return server.config.Hostname
  49 }
  50
  51 func (server *smtpServer) TLSConfig() *tls.Config {
  52         return nil
  53 }
  54
  55 func (server *smtpServer) VerifyAddress(addr mail.Address) smtp.ReplyLine {
  56         if server.maildropForAddress(addr) == "" {
  57                 return smtp.ReplyBadMailbox
  58         }
  59         return smtp.ReplyOK
  60 }
  61
  62 func (server *smtpServer) OnEHLO() *smtp.ReplyLine {
  63         return nil
  64 }
  65
  66 func (server *smtpServer) OnMessageDelivered(en smtp.Envelope) *smtp.ReplyLine {
  67         maildrop := server.maildropForAddress(en.RcptTo[0])
  68         if maildrop == "" {
  69                 // TODO: log error
  70                 return &smtp.ReplyBadMailbox
  71         }
  72
  73         f, err := os.Create(path.Join(maildrop, en.ID+".msg"))
  74         if err != nil {
  75                 // TODO: log error
  76                 return &smtp.ReplyBadMailbox
  77         }
  78
  79         smtp.WriteEnvelopeForDelivery(f, en)
  80         f.Close()
  81         return nil
  82 }
  83
  84 func (server *smtpServer) maildropForAddress(addr mail.Address) string {
  85         domainIdx := strings.LastIndex(addr.Address, "@")
  86         if domainIdx == -1 {
  87                 return ""
  88         }
  89
  90         domain := addr.Address[domainIdx+1:]
  91
  92         for _, s := range server.config.Servers {
  93                 if domain == s.Domain {
  94                         return s.MaildropPath
  95                 }
  96         }
  97
  98         return ""
  99 }