I tried padding with 0 0 1 1 0 0 0 0 ('0') and with 0 0 0 0 0 0 0, and with
your padkey function, but I don't get the proper results. Also, the 0x5c and
0x36 from the ascii table correspond to '/' and '6', yours results in
ungraphable members.
You said other issues exist as well, I would appreciate it if you could point
them out.
Feb 2, 2022, 17:32 by [email protected]:
> Actually, for the general case, the hash function may have an output
> size smaller than the block size.
>
> So:
>
> padkey=: {{
> if.x < # y do. y=. u y end.
> x{.y,x#{.a.
> }}
>
> FYI,
>
> --
> Raul
>
> On Wed, Feb 2, 2022 at 6:51 AM Raul Miller <[email protected]> wrote:
>
>>
>> On Wed, Feb 2, 2022 at 4:41 AM 'Viktor Grigorov' via Programming
>> <[email protected]> wrote:
>> > I wanted to see if J could be faster than bespoke C programs (specifically
>> > aircrack-ng, ~10k/s on my machine).
>> > From the wiki pages for SHA1 (turns outs there exists a foreign so I
>> > dropped it), HMAC, and PBKDF2I assembled:
>> > sha1=:1&(128!:6)
>> > bs=:512%8 NB. block size in bytes for md5, sha1, sha224, sha256
>> > opad=:bs(([,(#@]))$])0 1 0 1 1 1 0 0 NB. 0x5c, outer padding byte up to
>> > block size
>> > ipad=:bs(([,(#@]))$])0 0 1 1 0 1 1 0 NB. 0x36, inner padding byte up to
>> > block size
>> >
>> > hmac=:{{)a NB. assuming y of form 'key';'msg'
>> > if.bs&<@#key=.{.>y do.key=.u key end. NB. use hash of key as key, if
>> > greater than block size
>> > key=.((],(((bs&-@#),8:)$0:))@((8:#2:)#:(a.&i.)))key NB. pad 0s to right up
>> > to block size; do 8 bits of ascii
>> > u(({&a.@#.(key~:opad)),u(({&a.@#.(key~:ipad)),{:>y))
>> > }}
>> >
>> > sha1 hmac 'key';';msg'
>> > I am getting the wrong hashes back with examples from the wiki examples,
>> > ones generated from https://cryptotools.net/hmac What exactly am I missing?
>>
>> One issue (not the only issue) I think has to do with how you pad the key.
>>
>> If I understand https://en.wikipedia.org/wiki/HMAC correctly, this
>> will pad the key:
>>
>> padkey=: {{
>> if.x < # y do. u y
>> else. x{.y,x#{.a.
>> end.
>> }}
>>
>> And, I should expect that sha1 hmac (bs sha1 padkey 'key');';msg'
>> would have the same result as sha1 hmac 'key';';msg'
>>
>> I haven't looked any deeper than this, here.
>>
>> Good luck,
>>
>> --
>> Raul
>>
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