Wouldn't it type less if
key=. 128{.x,128#{.a.
or
key=. 128{.!.({.a.)x
On Dec 20, 2017 12:01 PM, "Scott Locklin" <[email protected]> wrote:
> This verb might be useful to someone at some point. Pretty
> straightforward stuff, but fiddley and no point in reinventing the wheel
> if someone else needs it.
>
> https://en.wikipedia.org/wiki/Hash-based_message_authentication_code
>
>
> NB. hmac signature
> NB. x key, y needs signature
> hmac=: 4 : 0
> key=. x,(128 - #x) # 0{a.
> ixorkey =. ((22 b.)&(16b36) a. i. key){a.
> raw=. _5 (128!:6) ixorkey,y
> oxorkey =. ((22 b.)&(16b5c) a. i. key){a.
> 5 (128!:6) oxorkey,raw
> )
>
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