one short question

[Kevin Darcy]

Nah, the IPv4 address space is only 2^32, so just do a reverse lookup of every possible address and
extract the RDATAs which happen to be in the desired domain. Much faster. And we all know that every A
record has a corresponding PTR, right? :-)


- Kevin

Brad Knowles wrote:

> At 9:08 AM +0200 6/1/01, Andras Horvai wrote:
>
> >  Can anybody tell me how can I query all the IN A  which are in a zone.
> >  I only know the name of the domain but I don't know the additional records.
> >  The zone transfer doesn't work. I only need the A records.
>
>         If zone transfer doesn't work, you'll have to do this the hard
> way.  Since a hostname label can be up to 64 characters long, and can
> include alphabetic, numeric, and dash characters, you'll have to
> generate all possible hostnames that can be generated from this set
> of characters, and then query each and every one of them individually.
>
>         If I remember my math correctly, this would be the following
> mathematical sequence:
>
>                 sum(37 + 37^2 + 37^3 + 37^4 + ... + 37^64)
>
>         Which I believe is the same as 37^65 - 1.  Unfortunately, the
> calculator on my computer doesn't go that high, but using the "bc"
> program on a Unix machine tells me that this number should be:
>
> 857259021850231924895241213159876151487328207796055469880503919715040147457850556528034327122015486756
>
>         This number is larger than the number referred to as a "Googol",
> or 10^100.  IIRC, there are believe to be something like 10^40 atoms
> in the Universe.  Also, I believe that the current age of the
> Uniververse is believed to be something like 15 billion years, and if
> you use the following calculation to turn this into seconds:
>
>                 15 * 1,000,000,000 * 365 * 24 * 60 * 60
>
>         You arrive at the number 473040000000000000.
>
>         Your number is still
> 1812233683938423653169375133519102298933130829942616839760916454665652265047037367935
> times larger than the believed age of the Universe, so even if you
> did a million DNS queries per second, it would still take you another
> 1812233683938423653169375133519102298933130829942616839760916454665652265047037
> seconds to complete your task.
>
>         This translates into
> 57465553143658791640327724934015166759675635145313826730115311221006223
> years.  If you consider the believed age of the Universe to be a
> single timescale known as Age, then this would be
> 121481382427825958989361840296835715287662005634436467 Ages.
>
>         You're going to be working on this task for a while.  I suggest
> that you start getting some sleep now.
>
> --
> Brad Knowles, <brad.knowles at skynet.be>
>
> /*        efdtt.c  Author:  Charles M. Hannum <root at ihack.net>          */
> /*       Represented as 1045 digit prime number by Phil Carmody         */
> /*     Prime as DNS cname chain by Roy Arends and Walter Belgers        */
> /*                                                                      */
> /*     Usage is:  cat title-key scrambled.vob | efdtt >clear.vob        */
> /*   where title-key = "153 2 8 105 225" or other similar 5-byte key    */
>
> dig decss.friet.org|perl -ne'if(/^x/){s/[x.]//g;print pack(H124,$_)}'