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 ) ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
