crypto dependency in bit sliced AES

[Russell King - ARM Linux]

On Sat, Nov 23, 2013 at 04:16:18PM -0800, Linus Torvalds wrote:
>   Received-SPF: neutral (google.com: 178.18.16.133 is neither
> permitted nor denied by best guess record for domain of
> herbert at gondor.apana.org.au) client-ip=178.18.16.133;
>   Authentication-Results: mx.google.com;
>        spf=neutral (google.com: 178.18.16.133 is neither permitted nor
> denied by best guess record for domain of herbert at gondor.apana.org.au)
> smtp.mail=herbert at gondor.apana.org.au
> 
> with that whole "best guess record for domain" crap. So at the very
> least your spf records are questionable.
> 
> And when I do "nslookup -q=mx gondor.apana.org.au" I get:
> 
>   Server: 192.168.0.1
>   Address: 192.168.0.1#53
> 
>   Non-authoritative answer:
>   gondor.apana.org.au canonical name = gondor.hengli.com.au.
>   gondor.hengli.com.au mail exchanger = 10 mx2.hengli.com.au.
>   gondor.hengli.com.au mail exchanger = 5 mx1.hengli.com.au.
> 
>   Authoritative answers can be found from:"

What probably doesn't help is this... from my exim logs:

<= herbert at gondor.apana.org.au H=ringil.hengli.com.au
(fornost.hengli.com.au) [178.18.16.133]:51158 I=[78.32.30.222]:25 P=esmtps
X=TLSv1:AES256-SHA:256 S=2150 id=20131123013924.GA16533 at gondor.apana.org.au
T="Re: crypto dependency in bit sliced AES" for linux at arm.linux.org.uk

So, this was received from IP 178.18.16.133:
133.16.18.178.in-addr.arpa domain name pointer ringil.hengli.com.au.
ringil.hengli.com.au has address 178.18.16.133

Good, it matches - exim's H= line not being in parens also tells us that.

The EHLO string though (fornost.hengli.com.au):

fornost.hengli.com.au has address 209.40.204.226
226.204.40.209.in-addr.arpa domain name pointer helcar.apana.org.au.
helcar.apana.org.au has address 209.40.204.226

So, the SMTP server which claims to be fornost which seems to be running
on 178.18.16.133 has a different IP address in DNS of 209.40.204.226.
That probably doesn't help.

Let me put it another way: this makes it look like you're impersonating
a different server.  Now, while it may be true that EHLO strings aren't
supposed to be used to block email, there's allowable scope for "local
policy" to do things like treating such stuff as a potential spam source.