From mboxrd@z Thu Jan  1 00:00:00 1970
From: Simon Lodal <simonl@parknet.dk>
Subject: Re: RFC: Partial IP4 syntax
Date: Wed, 29 Sep 2004 07:42:38 +0200
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To: Ben Efros <ben@xgendev.com>
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What tools are passing IP's literally as full 32bits? I understand why 
programs (especially in script languages) might do it internally, but 
between programs?

Funny, works with ping, but not ssh. Works with iptables for --src and 
--dst (surprise). But not for SNAT --to-source.

Just looked at RFC 1123, it only talks about dotted decimal 
representation. The 32bit form is not even documented anywhere afaik, 
and honestly I do not remember seeing it.

If it is really a problem I agree my scheme will break it. Could 
probably be solved by changing the default to incomplete-at-beginning, 
so 10 = .10 = 0.0.0.10.


Simon


>> Iknow IP address syntax should not change every day. But this will not 
>> break or exclude old syntax. I do not see it clashing with 
>> other/future syntax.
> 
> 
> Wrong.  IP numbers can also be written in 32-bit unsigned notation.  In 
> your first example:
> 10 being  10.0.0.0/8
> 10 is actually treated as unsigned 32bit int, meaning you're address is 
> actually 0.0.0.10
> Try this command and see for yourself:
> "ping 5000"
> Notice how ping is actually sending to "0.0.19.136" ?
> 
> This is done because 32-bit addresses should be representable as a 32bit 
> number and not just as a string representation of the address for a 
> variety of reasons.
> 
> Unfortunately your idea would break a LOT of very useful tools and ways 
> of representing valid ip numbers.
> 
> Ben