On Sun, 16 Jun 2002, Alan J. Flavell wrote:
> To: <Undisclosed-Recipient:;>
>
> , about the legality of which I know different views have been
> expressed.
Just to confirm what has already been posted:
1. This is indeed illegal. The only thing you can have inside <> is
localpart@domain.
2. In Exim 3, headers_check_syntax is all or nothing. To change that,
you have to patch the code.
3. In Exim 4, because the check is within an ACL, you can make it
conditional on various things. For example, you could check for that
specific text in To:. However, skipping the check skips if for all
header lines, of course, not just for that one.
4. Also in Exim 4, you can put the test on a "warn" statement that adds
a header line to the message instead of rejecting.
> My question would be then whether this checking and logging would
> leave some trace which the system_filter could sense, and apply some
> more-elaborate tests before deciding whether to pass the mail on, or
> to bounce it.
I guess I can read the code faster than you can .... pause .... no,
Exim 3 just logs the error. It doesn't add anything to the message.
Finally: there is a new item on the Wish List asking for a means of
rewriting header lines in general, before any of the checking happens.
If ever that gets implemented, it could be used to rewrite a broken To:
header such as the above so that it would pass the syntax check. This
means that the other headers lines would then also be checked.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
