PtokaX forum

any chance of a lock2key lua, maybe even using some lib, i've tried to write, but have problems with xor....

language samples: http://66.249.93.104/search?q=cache:mz5rusF3zw8J:dcplusplus.sourceforge.net/wiki/index.php/LockToKey%3Fversion%3D25+dc+locktokey&hl=da (http://66.249.93.104/search?q=cache:mz5rusF3zw8J:dcplusplus.sourceforge.net/wiki/index.php/LockToKey%3Fversion%3D25+dc+locktokey&hl=da)

thanks in advance...

What are u sceeming upto now? ^^

Nuh sorry mate, i checked around and tried a few things, none of them worked.

Its prob not the algorithm, but lua's encoding ;) U want to be using utf7 or 8, cant remember which one

try this:
-- Coded by Mardeg
function bODD(x)
       return x ~= math.floor(x / 2) * 2
end

function bitwise(x, y, bw)
       local c, p = 0, 1
       while x > 0 or y > 0 do
           if bw == "xor" then
               if (bODD(x) and not bODD(y)) or (bODD(y) and not bODD(x)) then
                       c = c + p
               end
           elseif bw == "and" then
               if bODD(x) and bODD(y) then
                       c = c + p
               end
           elseif bw == "or" then
               if bODD(x) or bODD(y) then
                       c = c + p
               end
           end
           x = math.floor(x / 2)
           y = math.floor(y / 2)
           p = p * 2
       end
       return c
end

function nibbleswap(bits)
  return bitwise(bitwise(bits*(2^4),240,"and"),bitwise(math.floor(bits/(2^4)),15,"and"),"or")
end

function lock2key(lock)
local key = {}
table.insert(key,bitwise(bitwise(bitwise(string.byte(lock,1),string.byte(lock,-1),"xor"),string.byte(lock,-2),"xor"),5,"xor"))
for i=2,string.len(lock),1 do
table.insert(key,bitwise(string.byte(lock,i),string.byte(lock,i - 1),"xor"))
end
local g = {["5"]=1,["0"]=1,["36"]=1,["96"]=1,["124"]=1,["126"]=1}
for i=1,table.getn(key),1 do
local b = nibbleswap(rawget(key,i))
rawset(key,i,(g[tostring(b)] and string.format("/%%DCN%03d%%/",b) or string.char(b)))
end
return table.concat(key)
end


well finally found my way back to the forum, seems it didnt, work but very nice try, i'll see if i can get it working, i actually think its my fault, a socket prob.....

Thanks!  :]

No problem, although I just did it as an exercise to compare different languages doing the same thing, so never tested the Lua version.

Specific things that may be worth checking are whether:
? arithmetic is allowable inside string.byte(lock,i - 1)
? string.format("/%%DCN%03d%%/",b) is correct
? each table.insert really does add each value to the end of the table
? the code can be optimised down in size without help from plugins or losing readability (this is just so it looks less daunting on the code comparison page: http://wiki.dcpp.net/index.php/LockToKey#Lua_5.0.2B - especially when I see how compact I made the Javascript example, still waiting for someone to make a Firefox extension to test that one.)

QuoteOriginally posted by Mardeg
? arithmetic is allowable inside string.byte(lock,i - 1)

It is.

QuoteOriginally posted by Mardeg
each table.insert really does add each value to the end of the table

It does, unless you explicitly specify the position.

I've noticed that ptokax simply drops the connection without feedback if $Supports is not sent before $Key if that's any help.