[Greylist-users] Bagley: A standalone binary greylister for Exim 4

[William Blunn]

> Using an ACL hook means that I can (temporarily) reject messages before
> receiving the message DATA, whereas local_scan only works after the
> message DATA has already been received.

Here is my ACL hook, which I put in the ACL pointed to by the acl_smtp_rcpt directive (by default "acl_check_rcpt"):

  require  condition = ${run{/usr/local/lib/bagley/bagley $sender_host_address "${sg{$sender_address}{([\\\\"])}{\\\\\$1}}" "${sg{${quote_local_part:$local_part}@$domain}{([\\\\"])}{\\\\\$1}}"}}

I have put in escaping to cope with the fact that Exim's expansion item "run" appears to take a space-separated optionally-double-quoted ARG list, but I need the arguments to go exactly into argv[1], argv[2], argv[3], regardless of whether they are empty or contain spaces or quotes or backslashes.

The escaping I have put in seems to cope alright with the worst scenarios I have been able to think of, e.g.

  caller = 1.2.3.4
  MAIL FROM: <>
  RCPT TO: <"\" \\ \""@wibble.com>

Bill

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