Comparison

Added HMAC utility module Produces HMAC codes using all the supported hashes (md5, sha1, sha256)

comparison

equal deleted inserted replaced

-:81e01809de54
+:3135cf40110d
+local hashes = require "util.hashes"
+local xor = require "bit".bxor
+module "hmac"
+local function arraystr(array)
+t = {}
+for i = 1,table.getn(array) do
+table.insert(t, string.char(array[i]))
+end
+return table.concat(t)
+end
+--[[
+key
+the key to use in the hash
+message
+the message to hash
+hash
+the hash function
+blocksize
+the blocksize for the hash function in bytes
+hex
+return raw hash or hexadecimal string
+--]]
+function hmac(key, message, hash, blocksize, hex)
+local opad = {}
+local ipad = {}
+for i = 1,blocksize do
+opad[i] = 0x5c
+ipad[i] = 0x36
+end
+if #key > blocksize then
+key = hash(key)
+end
+for i = 1,#key do
+ipad[i] = xor(ipad[i],key:sub(i,i):byte())
+opad[i] = xor(opad[i],key:sub(i,i):byte())
+end
+opad = arraystr(opad)
+ipad = arraystr(ipad)
+if hex then
+return hash(opad..hash(ipad..message), true)
+else
+return hash(opad..hash(ipad..message))
+end
+end
+function md5(key, message, hex)
+return hmac(key, message, hashes.md5, 64, hex)
+end
+function sha1(key, message, hex)
+return hmac(key, message, hashes.sha1, 64, hex)
+end
+function sha256(key, message, hex)
+return hmac(key, message, hashes.sha256, 64, hex)
+end
+return _M