PostSRSd integration with Exim
==============================

## SRS Return router

If using a domain solely for SRS return addresses:

    SRS_DOMAIN = srs.your.domain
    
    begin routers
    
    srs_return:
      caseful_local_part
      domains = SRS_DOMAIN
      driver = redirect
      allow_fail
      data = ${if match {$local_part}{\N(?i)^srs[01]=\N} \
    	{${if match \
    	  {${readsocket{inet:localhost:10002}{get ${quote_local_part:$local_part_prefix$local_part}@$domain}{3s}}} \
    	  {\N^200 (.+)\N} \
    	  {$1} \
    	  {:fail: Invalid SRS bounce} \
    	}} \
    	{:fail: Invalid SRS bounce} \
      }
      no_more

If your SRS domain is also used for other addresses:

    SRS_DOMAIN = srs.your.domain
    
    begin routers
    
    srs_return:
      caseful_local_part
      domains = SRS_DOMAIN
      local_part_prefix = srs0= : srs1=
      driver = redirect
      allow_fail
      data = ${if match \
        {${readsocket{inet:localhost:10002}{get ${quote_local_part:$local_part_prefix$local_part}@$domain}{3s}}} \
        {\N^200 (.+)\N} \
        {$1} \
        {:fail: Invalid SRS bounce} \
      }

## Rewriting outgoing mail in the SMTP transport

The following excludes locally submitted mail, or mail submitted by authenticated
users from SRS rewriting. Of course, if the sender address is already in
one of our local domains, there is no need to rewrite the address.

    begin transports
    
    remote_smtp:
      debug_print = "T: remote_smtp for $local_part@$domain"
      driver = smtp
      return_path = ${if and { \
    		{!match_ip{$sender_host_address}{:@[]}} \
    		{!def:authenticated_id} \
    		{!match_address {$sender_address} { : *@+local_domains : *@+virtual_domains : SRS_DOMAIN}} \
    	} \
    	{${if match \
    	  {${readsocket{inet:localhost:10001}{get $sender_address}{3s}}} \
    	  {\N^200 (.+)\N} \
    	  {$1} \
    	  fail } \
    	} \
    	fail }