Date: Tue, 3 Feb 2004 02:15:29 +0100
From: Martin Treusch von Buttlar
Subject: RPR ported to exim4

Hi,

I have successfully ported your RPR-implementation to exim 4.30. Please
understand that I had to change the indentation and some conditions,
while I was trying to understand this.

Some things could be further simplified, but I am to tired right now :)

If you don't mind I will put this onto a website for you to link to. You
can use it for any purpose, as long as you include a reference to me.

Here are the necessary routers:

rpr_lookup_mx:
  driver = dnslookup
  senders = ! *@+local_domains
  ignore_target_hosts = 127.0.0.0/8
  domains = ! +local_domains
  verify = false
  address_data = ${eval:$tod_epoch+86400*5}=\
                   ${sg {${sg {$sender_address}{([=#%_])}{_\$1}}}{@}{#}}=\
                   ${sg {$original_local_part}{([=#%_])}{_\$1}}\
                   ${if eq {$domain}{$original_domain}\
                     {%$original_domain@$primary_hostname}\
                     {@$original_domain}}
  # Check for empty sender_address and prevent bounces from being rewritten
  condition = ${if and {{!eq {$sender_address}{}}\
                        {!match {$h_X-RPR-Return:}{$primary_hostname}}\
                       }{1}{0}}
  headers_add = "X-RPR-Rewrite: SMTP envelope sender rewritten by $primary_hostname\n\
                 \tSee RPR_EXPLAIN_URL"
  errors_to = bounce-${md5:RPR_SECRET-$address_data}-$address_data
  transport = remote_smtp

rpr_return:
  driver = redirect
  local_part_prefix = bounce-
  senders = :
  condition = ${if match {$local_part}{\N^([0-9a-f]{32})-(\d+=(?:.*[^_])?(?:_[_#])*#[^=#]+=.+)$\N} {${if eq {${md5:RPR_SECRET-$2@$domain}}{$1} {1}{0}}}{0}}
  data = ${if match {$local_part}{\N^[0-9a-f]{32}-(\d+)=((?:.*[^_])?(?:_[_#])*)#([^=#]+)=(.+)$\N}{ ${sg {${if >{$1}{$tod_epoch} {$2@$3}{"postmaster@gnuher.de"}}} {_([_=#%])}{\$1}} }{"postmaster@$domain"}}
  headers_add = "X-RPR-Return: DSN routed to destination via $primary_hostname\n\
                 \tSee RPR_EXPLAIN_URL"

rpr_error_checksum:
  driver = redirect
  local_part_prefix = bounce-
  senders = :
  condition = ${if match {$local_part}{\N^([0-9a-f]{32})-(\d+=(?:.*[^_])?(?:_[_#])*#[^=#]+=.+)$\N} {${if eq {${md5:RPR_SECRET-$2@$domain}}{$1} {1}{0}}}{0}}
  data = "postmaster@$domain"
  headers_add = "X-RPR-Alert: Checksum mismatch!"

rpr_error_nodsn:
  driver = redirect
  local_part_prefix = bounce-
  condition = ${if match {$local_part}{\N^([0-9a-f]{32})-(\d+=(?:.*[^_])?(?:_[_#])*#[^=#]+=.+)$\N} {${if eq {${md5:RPR_SECRET-$2@$domain}}{$1} {1}{0}}}{0}}
  data = "postmaster@$domain"
  headers_add = "X-RPR-Alert: Not a DSN (non-empty return-path)!"

Thanks for the great work

Martin