Re: inconsistent address treatment.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 12/26/2010 07:47 AM, Jan Engelhardt wrote:
On Sunday 2010-12-26 13:10, Amos Jeffries wrote:

On 25/12/10 10:48, Jan Engelhardt wrote:
On Friday 2010-12-24 16:32, Stephen Clark wrote:
Because -d takes a prefix and --to-source takes an address range.
So? you can't parse
205.201.149.214/32-205.201.149.218/32
a.b.c.d/32 is a prefix notation, even though it represents a single
address. IMO it does not make sense to use a prefix notation in an
interval, so I don't see why the parser should handle it. AFAICS, other
commands such as 'ip' from iproute don't accept /32 prefixes where a
single address is expected either.
Well It is just one more idiosyncrasy one has to remember, when to me there
is no obvious reason
Historical reasons.

Possible extra explanations:

- DNAT was added later than the -s argument, and someone thought
   it's better to use a range, since a range can be more expressive
   than addr[/prefixlen] for the same memory usage.
- On the other hand, since iptables also accepts addr[/mask], and it
   also allows /masks that are not representable as a /prefixlen, it
   is not necessarily specifying a contiguous range which may be
   useless to use with DNAT to some.
FWIW: we (Squid project) use the syntax "ip[-ip][/mask]". This is simple enough
to parse and is a bit more flexible.
Indeed, but we don't have the space for it ;-)
There are just two uint32s available in the current struct ipt_ip,
so it's either ip-ip or ip/mask.
Of course, in the near future, the ipv4 match can be extended just like
other extensions (revision bump).

That is a reasonable answer.


--

"They that give up essential liberty to obtain temporary safety,
deserve neither liberty nor safety."  (Ben Franklin)

"The course of history shows that as a government grows, liberty
decreases."  (Thomas Jefferson)



--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Netfitler Users]     [LARTC]     [Bugtraq]     [Yosemite Forum]

  Powered by Linux