Re: [exim] BODY=7BIT

On 2011-03-13 at 11:35 +1000, Ted Cooper wrote:
> I've been getting a LOT of errors similar to the following in my logs. I
> haven't cared all that much since after some initial quick checking,
> every one of the connections ended up being a spam bot that would have
> been blocked by other means anyway.
>
> 2011-02-24 09:25:26 SMTP syntax error in "MAIL
> FROM:<fpoole@???> SIZE=1016 BODY=7BIT"
> H=r190-64-150-215.dialup.adsl.anteldata.net.uy (anteldata.net.uy)
> [190.64.150.215] I=[203.211.140.242]:25 malformed address: SIZE=1016
> BODY=7BIT may not follow <fpoole@???>
>
> However, after some very quick checks, it seems that this construct is
> actually valid. Each host is using EHLO so any esmtp extensions should
> be available.

No: each ESMTP extension which is advertised to a client is available.
The BODY=7BIT construct is a feature available when the 8BITMIME
capability is advertised.

Although Exim is 8-bit clean, it does not currently perform any
down-conversions when talking to a remote mailserver, thus does not
advertise 8BITMIME by default. If you run a mail-server which accepts
mail for delivery into an inbox and does not send mail outbound again,
then turning on the accept_8bitmime global option will cause Exim to
advertise 8BITMIME and the BODY=7BIT extension will be supported.

Anything using an extension's features when the extension wasn't
advertised to it is broken.

-Phil