New Hash

block.lua

function log2 (x) return math.log(x) / math.log(2) end
 
function entropy (X)
	local N, count, sum, i = X:len(), {}, 0
	for char = 1, N do
		i = X:sub(char, char)
		if count[i] then
			count[i] = count[i] + 1
		else
			count[i] = 1
		end
	end
	for n_i, count_i in pairs(count) do
		sum = sum + count_i / N * log2(count_i / N)
	end
	return -sum
end

local hexToBin_lut={ ["0"]="0000", ["1"]="0001", ["2"]="0010", ["3"]="0011", ["4"]="0100", ["5"]="0101", ["6"]="0110", ["7"]="0111", ["8"]="1000", ["9"]="1001", ["a"]="1010", ["b"]="1011", ["c"]="1100", ["d"]="1101", ["e"]="1110", ["f"]="1111", }
local binToHex_lut={ ["0000"]="0", ["0001"]="1", ["0010"]="2", ["0011"]="3", ["0100"]="4", ["0101"]="5", ["0110"]="6", ["0111"]="7", ["1000"]="8", ["1001"]="9", ["1010"]="a", ["1011"]="b", ["1100"]="c", ["1101"]="d", ["1110"]="e", ["1111"]="f", }

local function toBinary(num) 
  return string.format("%x",num):gsub(".",function(v) return hexToBin_lut[v] end):match("^[0]*(%d*)$")
end

function string.hexbin(str)
	local bin = ""
	for i=1,#str do
		bin = bin .. hexToBin_lut[string.sub(str,i,i)]
	end
	return bin
end

function string.binhex(str)
	local res = ""
	for i=1,#str,4 do
		res = res .. binToHex_lut[string.sub(str,i,i+3)]
	end
	return res
end

function string.to_hex(str)
	return (str:gsub('.', function(c)
		return string.lower(string.format('%02x', string.byte(c)))
	end))
end

function string.from_hex(str)
	return (str:gsub('..', function(cc)
		return string.char(tonumber(cc,16))
	end))
end

function rand(n)
	t = {}
	for i = 1, n do
		t[i] = string.char(math.random(0,255))
	end
	--return table.concat(t)
	return block(tostring(table.concat(t)), n*8)
end

function xor(a,b)
	local t = {}
	for i = 1, #a do
		t[i] = string.char(bit.bxor(string.byte(a,i,i),string.byte(b,i,i)))
	end
	return table.concat(t)
end

function block(message, blocksize, stsz, rounds)
	blocksize = blocksize or 256
	blocksize2=blocksize*4
	local rounds = rounds or 4
	local stsz = stsz or 128--bytes
	local stm1 = stsz - 1
	local b, c, d, e = sb or 3, sc or 5, sd or 8, se or 13
	local state = {}
	local rsl = "0"
	local hash = {}
	for j = 1, #message do
		for k=1,rounds do
		for i = 1, stsz do
			e = ((state[bit.bxor(d,stm1)] or 0) * string.byte(string.sub(message,j,j)))
			state[bit.bxor(d,stm1)+(e%2)] = bit.bxor(b,c)
			state[i]= - bit.bnot(bit.bxor(b,c))
			b = (c + d)%256
			c = (d + e)%256
			d = e + (state[i] or 0)
			rsl = (rsl + d) % 256
		end
		end
	end
	for j = 1, blocksize2/4 do
		for k=1,rounds do
		for i = 1, stsz do
			e = (state[bit.bxor(d,stm1)] or 0) + (state[i] or 0)
			state[bit.bxor(d,stm1)+(e%stsz)+(e%2)] = bit.bnot(bit.bxor(b,c))
			state[i]= - bit.bnot(bit.bxor(b,c))
			b = (c + d)%256
			c = (d + e)%256
			d = e + (state[i] or 0)
			rsl = (rsl + d) % 256
			--io.write("\ns[",i,"]=",state[i] or '00')
		end
		end
		hash[j] = string.format("%02x", rsl)--:from_hex()
	end
	--return table.concat(hash):to_binary()--:to_hex()
	local binary = table.concat(hash):hexbin()
	local res = ""
	for i=1,#binary,2 do		--VON-NEUMAN EXTRACTOR
		if string.sub(binary,i,i) ~= string.sub(binary,i+1,i+1) then
			res = res .. string.sub(binary,i,i)
		end
	end
	while #res%4~=0 do
		res=res.."0"
	end
	res=string.binhex(res)
	return string.sub(res,1,blocksize/4)
	--return xor(string.sub(res,1,blocksize/4):from_hex(),table.concat(hash):from_hex()):to_hex()
end