Need help with SHA hashing.

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---	  *** SHA-1 algorithm for Lua ***	  ---
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--- Author:  Martin Huesser				   ---
--- Date:	2008-06-16					   ---
--- License: You may use this code in your	---
---		  projects as long as this header  ---
---		  stays intact.					---
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local strlen  = string.len
local strchar = string.char
local strbyte = string.byte
local strsub  = string.sub
local floor   = math.floor
local bnot	= bit.bnot
local band	= bit.band
local bor	 = bit.bor
local bxor	= bit.bxor
local shl	 = bit.lshift
local shr	 = bit.rshift
local h0, h1, h2, h3, h4
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local function LeftRotate(val, nr)
return shl(val, nr) + shr(val, 32 - nr)
end
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local function ToHex(num)
local i, d
local str = ""
for i = 1, 8 do
  d = band(num, 15)
  if (d < 10) then
   str = strchar(d + 48) .. str
  else
   str = strchar(d + 87) .. str
  end
  num = floor(num / 16)
end
return str
end
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local function PreProcess(str)
local bitlen, i
local str2 = ""
bitlen = strlen(str) * 8
str = str .. strchar(128)
i = 56 - band(strlen(str), 63)
if (i < 0) then
  i = i + 64
end
for i = 1, i do
  str = str .. strchar(0)
end
for i = 1, 8 do
  str2 = strchar(band(bitlen, 255)) .. str2
  bitlen = floor(bitlen / 256)
end
return str .. str2
end
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local function MainLoop(str)
local a, b, c, d, e, f, k, t
local i, j
local w = {}
while (str ~= "") do
  for i = 0, 15 do
   w[i] = 0
   for j = 1, 4 do
	w[i] = w[i] * 256 + strbyte(str, i * 4 + j)
   end
  end
  for i = 16, 79 do
   w[i] = LeftRotate(bxor(bxor(w[i - 3], w[i - 8]), bxor(w[i - 14], w[i - 16])), 1)
  end
  a = h0
  b = h1
  c = h2
  d = h3
  e = h4
  for i = 0, 79 do
   if (i < 20) then
	f = bor(band(b, c), band(bnot(B)/>/>/>/>/>/>, d))
	k = 1518500249
   elseif (i < 40) then
	f = bxor(bxor(b, c), d)
	k = 1859775393
   elseif (i < 60) then
	f = bor(bor(band(b, c), band(b, d)), band(c, d))
	k = 2400959708
   else
	f = bxor(bxor(b, c), d)
	k = 3395469782
   end
   t = LeftRotate(a, 5) + f + e + k + w[i]
   e = d
   d = c
   c = LeftRotate(b, 30)
   b = a
   a = t
  end
  h0 = band(h0 + a, 4294967295)
  h1 = band(h1 + b, 4294967295)
  h2 = band(h2 + c, 4294967295)
  h3 = band(h3 + d, 4294967295)
  h4 = band(h4 + e, 4294967295)
  str = strsub(str, 65)
end
end
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function Sha1(str)
str = PreProcess(str)
h0  = 1732584193
h1  = 4023233417
h2  = 2562383102
h3  = 0271733878
h4  = 3285377520
MainLoop(str)
return  ToHex(h0) ..
  ToHex(h1) ..
  ToHex(h2) ..
  ToHex(h3) ..
  ToHex(h4)
end
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