From dab1b130bd9922dfab82b227e2329f31deabda1f Mon Sep 17 00:00:00 2001 From: kikito Date: Fri, 30 Aug 2013 19:12:29 +0200 Subject: [PATCH] initial commit with working implementation, readme and license --- MIT-LICENSE.txt | 20 +++ README.md | 40 ++++++ md5.lua | 356 ++++++++++++++++++++++++++++++++++++++++++++++ spec/md5_spec.lua | 28 ++++ 4 files changed, 444 insertions(+) create mode 100644 MIT-LICENSE.txt create mode 100644 README.md create mode 100644 md5.lua create mode 100644 spec/md5_spec.lua diff --git a/MIT-LICENSE.txt b/MIT-LICENSE.txt new file mode 100644 index 0000000..1630e47 --- /dev/null +++ b/MIT-LICENSE.txt @@ -0,0 +1,20 @@ +Copyright (c) 2013 Enrique García Cota + Adam Baldwin + hanzao + Equi 4 Software + +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. diff --git a/README.md b/README.md new file mode 100644 index 0000000..6591c11 --- /dev/null +++ b/README.md @@ -0,0 +1,40 @@ +md5.lua +======== + +This pure-Lua module computes md5 in Lua 5.1. + +It implements md5.sum and md5.sumhex like the [kernel project md5 package](http://www.keplerproject.org/md5/), but it's done completely in Lua, with no dependencies on other libs or C files. + +Usage +===== + + local md5 = require 'md5' + + local md5_as_hex = md5.sumhex(message) -- returns a hex string + local md5_as_data = md5.sum(message) -- returns raw bytes + +Credits +======= + +This is a cleanup of an implementation by Adam Baldwin - https://gist.github.com/evilpacket/3647908 + +Which in turn was a mix of the bitwise lib, http://luaforge.net/projects/bit/ by hanzhao (`abrash_han - at - hotmail.com`), +and http://equi4.com/md5/md5calc.lua, by Equi 4 Software. + + +License +======= + +This library, as well as all the previous ones in which is based, is released under the MIT license (See license file for details). + +Specs +===== + +The specs for this library are implemented with [busted](http://ovinelabs.com/busted/). In order to run them, install busted and then: + + cd path/to/where/the/spec/folder/is + busted + + + + diff --git a/md5.lua b/md5.lua new file mode 100644 index 0000000..6007eef --- /dev/null +++ b/md5.lua @@ -0,0 +1,356 @@ +------------------------------------------------------------------------------- +-- MD5 computation in Lua (5.1) +------------------------------------------------------------------------------- +-- bit lib implementions + +local floor, abs, max = math.floor, math.abs, math.max +local char, byte, format, rep, sub = + string.char, string.byte, string.format, string.rep, string.sub + +local function check_int(n) + -- checking not float + if(n - floor(n) > 0) then + error("trying to use bitwise operation on non-integer!") + end +end + +local function tbl_to_number(tbl) + local n = #tbl + + local rslt = 0 + local power = 1 + for i = 1, n do + rslt = rslt + tbl[i]*power + power = power*2 + end + + return rslt +end + +local function expand(tbl_m, tbl_n) + local big = {} + local small = {} + if(#tbl_m > #tbl_n) then + big = tbl_m + small = tbl_n + else + big = tbl_n + small = tbl_m + end + -- expand small + for i = #small + 1, #big do + small[i] = 0 + end + +end + +local to_bits -- needs to be declared before bit_not + +local function bit_not(n) + local tbl = to_bits(n) + local size = max(#tbl, 32) + for i = 1, size do + if(tbl[i] == 1) then + tbl[i] = 0 + else + tbl[i] = 1 + end + end + return tbl_to_number(tbl) +end + +-- defined as local above +to_bits = function (n) + check_int(n) + if(n < 0) then + -- negative + return to_bits(bit_not(abs(n)) + 1) + end + -- to bits table + local tbl = {} + local cnt = 1 + while (n > 0) do + local last = math.mod(n,2) + if(last == 1) then + tbl[cnt] = 1 + else + tbl[cnt] = 0 + end + n = (n-last)/2 + cnt = cnt + 1 + end + + return tbl +end + +local function bit_or(m, n) + local tbl_m = to_bits(m) + local tbl_n = to_bits(n) + expand(tbl_m, tbl_n) + + local tbl = {} + local rslt = max(#tbl_m, #tbl_n) + for i = 1, rslt do + if(tbl_m[i]== 0 and tbl_n[i] == 0) then + tbl[i] = 0 + else + tbl[i] = 1 + end + end + + return tbl_to_number(tbl) +end + +local function bit_and(m, n) + local tbl_m = to_bits(m) + local tbl_n = to_bits(n) + expand(tbl_m, tbl_n) + + local tbl = {} + local rslt = max(#tbl_m, #tbl_n) + for i = 1, rslt do + if(tbl_m[i]== 0 or tbl_n[i] == 0) then + tbl[i] = 0 + else + tbl[i] = 1 + end + end + + return tbl_to_number(tbl) +end + +local function bit_xor(m, n) + local tbl_m = to_bits(m) + local tbl_n = to_bits(n) + expand(tbl_m, tbl_n) + + local tbl = {} + local rslt = max(#tbl_m, #tbl_n) + for i = 1, rslt do + if(tbl_m[i] ~= tbl_n[i]) then + tbl[i] = 1 + else + tbl[i] = 0 + end + end + + return tbl_to_number(tbl) +end + +local function bit_rshift(n, bits) + check_int(n) + + local high_bit = 0 + if(n < 0) then + -- negative + n = bit_not(abs(n)) + 1 + high_bit = 2147483648 -- 0x80000000 + end + + for i=1, bits do + n = n/2 + n = bit_or(floor(n), high_bit) + end + return floor(n) +end + +local function bit_lshift(n, bits) + check_int(n) + + if(n < 0) then + -- negative + n = bit_not(abs(n)) + 1 + end + + for i=1, bits do + n = n*2 + end + return bit_and(n, 4294967295) -- 0xFFFFFFFF +end + +-- convert little-endian 32-bit int to a 4-char string +local function lei_2_str(i) + local f=function (s) return char( bit_and( bit_rshift(i, s), 255)) end + return f(0)..f(8)..f(16)..f(24) +end + +-- convert raw string to big-endian int +local function str_2_bei(s) + local v=0 + for i=1, #s do + v = v * 256 + byte(s, i) + end + return v +end + +-- convert raw string to little-endian int +local function str_2_lei(s) + local v=0 + for i = #s,1,-1 do + v = v*256 + byte(s, i) + end + return v +end + +-- cut up a string in little-endian ints of given size +local function cut_le_str(s,...) + local o, r = 1, {} + local args = {...} + for i=1, #args do + table.insert(r, str_2_lei(sub(s, o, o + args[i] - 1))) + o = o + args[i] + end + return r +end + +local swap = function (w) return str_2_bei(lei_2_str(w)) end + +local function hex_to_binary(hex) + local result, _ = hex:gsub('..', function(hexval) + return string.char(tonumber(hexval, 16)) + end) + return result +end + +-- An MD5 mplementation in Lua, requires bitlib (hacked to use LuaBit from above, ugh) +-- 10/02/2001 jcw@equi4.com + +local FF = 0xffffffff +local CONSTS = { + 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, + 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, + 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, + 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, + 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, + 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, + 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, + 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, + 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, + 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, + 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, + 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, + 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, + 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, + 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, + 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391, + 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476 +} + +local f=function (x,y,z) return bit_or(bit_and(x,y),bit_and(-x-1,z)) end +local g=function (x,y,z) return bit_or(bit_and(x,z),bit_and(y,-z-1)) end +local h=function (x,y,z) return bit_xor(x,bit_xor(y,z)) end +local i=function (x,y,z) return bit_xor(y,bit_or(x,-z-1)) end +local z=function (f,a,b,c,d,x,s,ac) + a=bit_and(a+f(b,c,d)+x+ac,FF) + -- be *very* careful that left shift does not cause rounding! + return bit_or(bit_lshift(bit_and(a,bit_rshift(FF,s)),s),bit_rshift(a,32-s))+b +end + +local function transform(A,B,C,D,X) + local a,b,c,d=A,B,C,D + local t=CONSTS + + a=z(f,a,b,c,d,X[ 0], 7,t[ 1]) + d=z(f,d,a,b,c,X[ 1],12,t[ 2]) + c=z(f,c,d,a,b,X[ 2],17,t[ 3]) + b=z(f,b,c,d,a,X[ 3],22,t[ 4]) + a=z(f,a,b,c,d,X[ 4], 7,t[ 5]) + d=z(f,d,a,b,c,X[ 5],12,t[ 6]) + c=z(f,c,d,a,b,X[ 6],17,t[ 7]) + b=z(f,b,c,d,a,X[ 7],22,t[ 8]) + a=z(f,a,b,c,d,X[ 8], 7,t[ 9]) + d=z(f,d,a,b,c,X[ 9],12,t[10]) + c=z(f,c,d,a,b,X[10],17,t[11]) + b=z(f,b,c,d,a,X[11],22,t[12]) + a=z(f,a,b,c,d,X[12], 7,t[13]) + d=z(f,d,a,b,c,X[13],12,t[14]) + c=z(f,c,d,a,b,X[14],17,t[15]) + b=z(f,b,c,d,a,X[15],22,t[16]) + + a=z(g,a,b,c,d,X[ 1], 5,t[17]) + d=z(g,d,a,b,c,X[ 6], 9,t[18]) + c=z(g,c,d,a,b,X[11],14,t[19]) + b=z(g,b,c,d,a,X[ 0],20,t[20]) + a=z(g,a,b,c,d,X[ 5], 5,t[21]) + d=z(g,d,a,b,c,X[10], 9,t[22]) + c=z(g,c,d,a,b,X[15],14,t[23]) + b=z(g,b,c,d,a,X[ 4],20,t[24]) + a=z(g,a,b,c,d,X[ 9], 5,t[25]) + d=z(g,d,a,b,c,X[14], 9,t[26]) + c=z(g,c,d,a,b,X[ 3],14,t[27]) + b=z(g,b,c,d,a,X[ 8],20,t[28]) + a=z(g,a,b,c,d,X[13], 5,t[29]) + d=z(g,d,a,b,c,X[ 2], 9,t[30]) + c=z(g,c,d,a,b,X[ 7],14,t[31]) + b=z(g,b,c,d,a,X[12],20,t[32]) + + a=z(h,a,b,c,d,X[ 5], 4,t[33]) + d=z(h,d,a,b,c,X[ 8],11,t[34]) + c=z(h,c,d,a,b,X[11],16,t[35]) + b=z(h,b,c,d,a,X[14],23,t[36]) + a=z(h,a,b,c,d,X[ 1], 4,t[37]) + d=z(h,d,a,b,c,X[ 4],11,t[38]) + c=z(h,c,d,a,b,X[ 7],16,t[39]) + b=z(h,b,c,d,a,X[10],23,t[40]) + a=z(h,a,b,c,d,X[13], 4,t[41]) + d=z(h,d,a,b,c,X[ 0],11,t[42]) + c=z(h,c,d,a,b,X[ 3],16,t[43]) + b=z(h,b,c,d,a,X[ 6],23,t[44]) + a=z(h,a,b,c,d,X[ 9], 4,t[45]) + d=z(h,d,a,b,c,X[12],11,t[46]) + c=z(h,c,d,a,b,X[15],16,t[47]) + b=z(h,b,c,d,a,X[ 2],23,t[48]) + + a=z(i,a,b,c,d,X[ 0], 6,t[49]) + d=z(i,d,a,b,c,X[ 7],10,t[50]) + c=z(i,c,d,a,b,X[14],15,t[51]) + b=z(i,b,c,d,a,X[ 5],21,t[52]) + a=z(i,a,b,c,d,X[12], 6,t[53]) + d=z(i,d,a,b,c,X[ 3],10,t[54]) + c=z(i,c,d,a,b,X[10],15,t[55]) + b=z(i,b,c,d,a,X[ 1],21,t[56]) + a=z(i,a,b,c,d,X[ 8], 6,t[57]) + d=z(i,d,a,b,c,X[15],10,t[58]) + c=z(i,c,d,a,b,X[ 6],15,t[59]) + b=z(i,b,c,d,a,X[13],21,t[60]) + a=z(i,a,b,c,d,X[ 4], 6,t[61]) + d=z(i,d,a,b,c,X[11],10,t[62]) + c=z(i,c,d,a,b,X[ 2],15,t[63]) + b=z(i,b,c,d,a,X[ 9],21,t[64]) + + return A+a,B+b,C+c,D+d +end + +local md5 = {} + +function md5.sumhexa(s) + local msgLen = #s + local padLen = 56 - msgLen % 64 + + if msgLen % 64 > 56 then padLen = padLen + 64 end + + if padLen == 0 then padLen = 64 end + + s = s .. char(128) .. rep(char(0),padLen-1) .. + lei_2_str(8*msgLen) .. lei_2_str(0) + + assert(#s % 64 == 0) + + local t = CONSTS + local a,b,c,d = t[65],t[66],t[67],t[68] + + for i=1,#s,64 do + local X = cut_le_str(sub(s,i,i+63),4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4) + assert(#X == 16) + X[0] = table.remove(X,1) -- zero based! + a,b,c,d = transform(a,b,c,d,X) + end + + return format("%08x%08x%08x%08x",swap(a),swap(b),swap(c),swap(d)) +end + +function md5.sum(s) + return hex_to_binary(md5.sumhexa(s)) +end + +return md5 diff --git a/spec/md5_spec.lua b/spec/md5_spec.lua new file mode 100644 index 0000000..d31ed04 --- /dev/null +++ b/spec/md5_spec.lua @@ -0,0 +1,28 @@ +local md5 = require('md5') + +local function hex2bin(hex) + local result, _ = hex:gsub('..', function(hexval) + return string.char(tonumber(hexval, 16)) + end) + return result +end + +describe('md5', function() + describe('md5.sumhexa', function() + it('works', function() + assert.equal(md5.sumhexa("asdf"), '912ec803b2ce49e4a541068d495ab570') + assert.equal(md5.sumhexa('The quick brown fox jumps over the lazy dog'), '9e107d9d372bb6826bd81d3542a419d6') + assert.equal(md5.sumhexa('The quick brown fox jumps over the lazy dog.'), 'e4d909c290d0fb1ca068ffaddf22cbd0') + assert.equal(md5.sumhexa(''), 'd41d8cd98f00b204e9800998ecf8427e') + end) + end) + + describe('md5.sum', function() + it('works', function() + assert.equal(md5.sum("asdf"), hex2bin '912ec803b2ce49e4a541068d495ab570') + assert.equal(md5.sum('The quick brown fox jumps over the lazy dog'), hex2bin'9e107d9d372bb6826bd81d3542a419d6') + assert.equal(md5.sum('The quick brown fox jumps over the lazy dog.'), hex2bin'e4d909c290d0fb1ca068ffaddf22cbd0') + assert.equal(md5.sum(''), hex2bin'd41d8cd98f00b204e9800998ecf8427e') + end) + end) +end)