Created
April 14, 2014 23:15
-
-
Save CapsAdmin/10689337 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
--[[ | |
Copyright (C) 2011 Chris Osgood <chris at luadev.com> | |
Permission is hereby granted, free of charge, to any person obtaining a copy | |
of this software and associated documentation files (the "Software"), to | |
deal in the Software without restriction, including without limitation the | |
rights to use, copy, modify, merge, publish, distribute, sublicense, and/or | |
sell copies of the Software, and to permit persons to whom the Software is | |
furnished to do so, subject to the following conditions: | |
The above copyright notice and this permission notice shall be included in | |
all copies or substantial portions of the Software. | |
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
IN THE SOFTWARE. | |
--]] | |
--[[ | |
SHA1 module | |
Notes: | |
final() may be called multiple times but only to retrieve the existing | |
hash. No data updates should be performed once the hash is finalized. | |
Example usage: | |
require('sha1') | |
-- Short form: | |
hash_bytes = sha1.hash('foobar') | |
-- Long form: | |
hash = sha1.init() | |
sha1.update(hash, 'foo') | |
sha1.update(hash, 'bar') | |
hash_bytes = sha1.final(hash) | |
--]] | |
local sha1 = {} | |
local ffi = require('ffi') | |
require('bit') | |
-- Local versions of bit operations ------------------------------------------- | |
local band, bor, bxor, bnot, rshift, lshift, rol, bswap, tohex = | |
bit.band, bit.bor, bit.bxor, bit.bnot, bit.rshift, bit.lshift, bit.rol, | |
bit.bswap, bit.tohex | |
if ffi.abi('be') then | |
bswap = function(n) return n end | |
end | |
-- Local utility -------------------------------------------------------------- | |
local uint32_ptr = ffi.typeof('uint32_t*') | |
local w = ffi.new('uint32_t[80]') | |
local function nbinary32(n) | |
return string.char(band(rshift(n, 24), 0xFF), | |
band(rshift(n, 16), 0xFF), | |
band(rshift(n, 8), 0xFF), | |
band(n, 0xFF)) | |
end | |
-- Main ----------------------------------------------------------------------- | |
--[[ | |
@param data Optional data to hash | |
@returns Hash object | |
--]] | |
function sha1.init(data) | |
-- Initialize variables | |
local hash = { | |
0x67452301, -- h0 | |
0xEFCDAB89, -- h1 | |
0x98BADCFE, -- h2 | |
0x10325476, -- h3 | |
0xC3D2E1F0, -- h4 | |
0, -- data length | |
'', -- partial data buffer | |
nil -- flag: hash is finalized | |
} | |
if data then sha1.update(hash, data) end | |
return hash | |
end | |
--[[ | |
@param hash Hash object | |
@param data Data to hash | |
@returns nothing | |
--]] | |
function sha1.update(hash, data) | |
if not data then return end | |
hash[6] = hash[6] + #data | |
data = hash[7]..data | |
-- Process 512-bit chunks | |
local steps = math.floor(#data / 64) * 16 - 1 | |
local pdata = ffi.cast(uint32_ptr, data) | |
for pos=0,steps,16 do | |
for i=0,15,1 do | |
w[i] = bswap(pdata[pos + i]) | |
end | |
for i=16,79,1 do | |
w[i] = rol(bxor(bxor(bxor(w[i-3], w[i-8]), w[i-14]), w[i-16]), 1) | |
end | |
local a,b,c,d,e = hash[1],hash[2],hash[3],hash[4],hash[5] | |
local f,k,temp | |
-- Main loop | |
for i=0,19,1 do | |
f, k = bor(band(b, c), band(bnot(b), d)), 0x5A827999 | |
temp = band(rol(a, 5) + f + e + k + w[i], 0xFFFFFFFF) | |
e,d,c,b,a = d,c,rol(b, 30),a,temp | |
end | |
for i=20,39,1 do | |
f, k = bxor(bxor(b, c), d), 0x6ED9EBA1 | |
temp = band(rol(a, 5) + f + e + k + w[i], 0xFFFFFFFF) | |
e,d,c,b,a = d,c,rol(b, 30),a,temp | |
end | |
for i=40,59,1 do | |
f, k = bor(bor(band(b, c), band(b, d)), band(c, d)), 0x8F1BBCDC | |
temp = band(rol(a, 5) + f + e + k + w[i], 0xFFFFFFFF) | |
e,d,c,b,a = d,c,rol(b, 30),a,temp | |
end | |
for i=60,79,1 do | |
f, k = bxor(bxor(b, c), d), 0xCA62C1D6 | |
temp = band(rol(a, 5) + f + e + k + w[i], 0xFFFFFFFF) | |
e,d,c,b,a = d,c,rol(b, 30),a,temp | |
end | |
hash[1] = band(hash[1] + a, 0xFFFFFFFF) | |
hash[2] = band(hash[2] + b, 0xFFFFFFFF) | |
hash[3] = band(hash[3] + c, 0xFFFFFFFF) | |
hash[4] = band(hash[4] + d, 0xFFFFFFFF) | |
hash[5] = band(hash[5] + e, 0xFFFFFFFF) | |
end | |
hash[7] = data:sub((steps+1) * 4 + 1) | |
end | |
--[[ | |
@param hash Hash object | |
@param data Optional data to hash | |
@param text Boolean: Return a text string (default returns binary string) | |
@returns Hash string (20 binary bytes or 40 text characters) | |
--]] | |
function sha1.final(hash, data, text) | |
if not hash[8] then | |
-- Pre-processing | |
data = data or '' | |
local len = (hash[6] + #data) * 8 | |
-- FIXME: need 64-bit "bit" functions | |
len = string.char(band(math.floor(len / 0x100000000000000), 0xFF), | |
band(math.floor(len / 0x1000000000000), 0xFF), | |
band(math.floor(len / 0x10000000000), 0xFF), | |
band(math.floor(len / 0x100000000), 0xFF), | |
band(rshift(len, 24), 0xFF), | |
band(rshift(len, 16), 0xFF), | |
band(rshift(len, 8), 0xFF), | |
band(len, 0xFF)) | |
local pad = 64 - ((hash[6] + 9) % 64) | |
if pad == 64 then pad = 0 end | |
data = data.."\128"..string.rep("\0", pad)..len | |
-- Produce the final hash value | |
sha1.update(hash, data) | |
hash[8] = true | |
end | |
if text then | |
return tohex(hash[1]).. | |
tohex(hash[2]).. | |
tohex(hash[3]).. | |
tohex(hash[4]).. | |
tohex(hash[5]) | |
else | |
return nbinary32(hash[1]).. | |
nbinary32(hash[2]).. | |
nbinary32(hash[3]).. | |
nbinary32(hash[4]).. | |
nbinary32(hash[5]) | |
end | |
end | |
--[[ | |
Convenience "all in one" hash function | |
@param data Data to hash | |
@param text Boolean: Return a text string (default returns binary string) | |
@returns Hash string (20 binary bytes or 40 text characters) | |
--]] | |
function sha1.hash(data, text) | |
return final(init(data), nil, text) | |
end | |
return sha1 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment