Valid netmasks for nethash type IP sets?

Valid netmasks for nethash type IP sets?

[Marcus Sundberg]

Hi,

is there any particular implementation detail behind the reason why
the nethash set rejects the special case of /32 and /0 ? I would find
it quite convenient if the nethash set was able to store "networks"
consisting of a single address as well as the "everything" network.

//Marcus
-- 
---------------------------------------+--------------------------
  Marcus Sundberg <marcus@ingate.com>  | Firewalls with SIP & NAT
 Software Developer, Ingate Systems AB |  http://www.ingate.com/

Re: Valid netmasks for nethash type IP sets?

[Jozsef Kadlecsik]

On Tue, 21 Jun 2005, Marcus Sundberg wrote:

> is there any particular implementation detail behind the reason why
> the nethash set rejects the special case of /32 and /0 ? I would find
> it quite convenient if the nethash set was able to store "networks"
> consisting of a single address as well as the "everything" network.

/0 (or 0) cannot be stored in any ipset type because zero value means
"element not set". /32 cannot be stored in nethash due to the packing
algorithm: with the chosen method it was possible to store the network
address and netmask value together just in 32 bits. And for single
addresses you can use iphash anytime.

Best regards,
Jozsef
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