*** qmail-smtpd.c-1.03-orig	Mon Jun 15 10:53:16 1998
--- qmail-smtpd.c	Tue Sep  2 14:19:10 2003
***************
*** 28,33 ****
--- 28,45 ----
  unsigned int databytes = 0;
  int timeout = 1200;
  
+ /* ENFORCE_FQDN_HELO patch by Paul Gregg <pgregg@pgregg.com> 29/08/2003
+    This patch will refuse mail servers which do not pass a . in the HELO
+    command.  Caveat - Mail servers should send HELO <fqdn> when sending mail
+    but servers should not block on non-fqdn helo commands.  Viruses tend to
+    not use fqdn hosts - so this patch - whilst not strictly RFC "complient"
+    may help in reducing inbound virii (e.g. SoBig.F virus)
+    Modified to run if a environment variable ENFORCE_FQDN_HELO is set.
+     Thanks to Richard Lyons <frob-qmail@webcentral.com.au> for that tip.
+    This check is not performed if RELAYCLIENT is set to ''.
+ */
+ #define ENFORCE_FQDN_HELO
+ 
  int safewrite(fd,buf,len) int fd; char *buf; int len;
  {
    int r;
***************
*** 48,53 ****
--- 60,69 ----
  void die_control() { out("421 unable to read controls (#4.3.0)\r\n"); flush(); _exit(1); }
  void die_ipme() { out("421 unable to figure out my IP addresses (#4.3.0)\r\n"); flush(); _exit(1); }
  void straynewline() { out("451 See http://pobox.com/~djb/docs/smtplf.html.\r\n"); flush(); _exit(1); }
+ #ifdef ENFORCE_FQDN_HELO
+ void die_nohelofqdn() { out("451 unable to accept non-FQDN HELO (#4.3.0)\r\n"); flush(); _exit(1); }
+ #endif
+ 
  
  void err_bmf() { out("553 sorry, your envelope sender is in my badmailfrom list (#5.7.1)\r\n"); }
  void err_nogateway() { out("553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)\r\n"); }
***************
*** 88,93 ****
--- 104,114 ----
  void dohelo(arg) char *arg; {
    if (!stralloc_copys(&helohost,arg)) die_nomem(); 
    if (!stralloc_0(&helohost)) die_nomem(); 
+ #ifdef ENFORCE_FQDN_HELO
+   if (!relayclient || str_len(relayclient)>0)
+     if (env_get("ENFORCE_FQDN_HELO") && (str_len(arg)-str_chr(arg, '.')==0))
+       die_nohelofqdn();
+ #endif
    fakehelo = case_diffs(remotehost,helohost.s) ? helohost.s : 0;
  }