From 54f368e2059d1d11127eda8bef6b2bbb4891368c Mon Sep 17 00:00:00 2001 From: Anatoly Date: Sat, 30 Oct 2021 17:37:06 +0300 Subject: [PATCH] Initial commit --- brute_crc32.lua | 28 ++++++++ brute_md5.lua | 30 ++++++++ crc32.lua | 171 ++++++++++++++++++++++++++++++++++++++++++++ i_know_my_crc32.lua | 19 +++++ i_know_my_md5.lua | 19 +++++ 5 files changed, 267 insertions(+) create mode 100644 brute_crc32.lua create mode 100644 brute_md5.lua create mode 100644 crc32.lua create mode 100644 i_know_my_crc32.lua create mode 100644 i_know_my_md5.lua diff --git a/brute_crc32.lua b/brute_crc32.lua new file mode 100644 index 0000000..edab74f --- /dev/null +++ b/brute_crc32.lua @@ -0,0 +1,28 @@ +local crc32 = require 'crc32' + +function edit_file(input_file, line, content) + local file = io.open(input_file, 'r') + local file_content = {} + for line in file:lines() do + table.insert(file_content, line) + end + io.close(file) + + file_content[line] = content + + file = io.open(input_file, 'w') + for index, value in ipairs(file_content) do + file:write(value..'\n') + end + io.close(file) +end + +local attempts = 0 + +repeat + local random_crc32 = crc32.hash(attempts) + edit_file('i_know_my_crc32.lua', 13, "local crc32_expected = '" .. random_crc32 .. "'") + local match = require('i_know_my_crc32') + attempts = attempts + 1 + print(attempts) +until(match) diff --git a/brute_md5.lua b/brute_md5.lua new file mode 100644 index 0000000..e51ed11 --- /dev/null +++ b/brute_md5.lua @@ -0,0 +1,30 @@ +-- This approach will take something septillion years + +local md5 = require 'md5' + +function edit_file(input_file, line, content) + local file = io.open(input_file, 'r') + local file_content = {} + for line in file:lines() do + table.insert(file_content, line) + end + io.close(file) + + file_content[line] = content + + file = io.open(input_file, 'w') + for index, value in ipairs(file_content) do + file:write(value..'\n') + end + io.close(file) +end + +local attempts = 0 + +repeat + local random_md5 = md5.sumhexa(attempts) + edit_file('i_know_my_md5.lua', 13, "local md5_expected = '" .. random_md5 .. "'") + local match = require('i_know_my_md5') + attempts = attempts + 1 + print(attempts) +until(match) diff --git a/crc32.lua b/crc32.lua new file mode 100644 index 0000000..56faa10 --- /dev/null +++ b/crc32.lua @@ -0,0 +1,171 @@ +--Copyright (c) 2007-2008 Neil Richardson (nrich@iinet.net.au) +--Copyright (c) 2011 Lance Li +-- +--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. + +--[[ +crc32.lua + +A pure Lua implementation of a CRC32 hashing algorithm. Slower than using a C implemtation, +but useful having no other dependancies. + +This module is based on Neil Richardson's implementation +http://luamemcached.googlecode.com/svn/trunk/CRC32.lua + +Changelog by Lance: + +depended on LuaJit's bitop module, +rebuileded table by using poly 0xEDB88320, +program little rewrited + +Synopsis + +local crc32 = require('crc32') +crchash = crc32.hash('a string') + +Methods: + +hashval = crc32.hash(val) + Calculates and returns (as an integer) the CRC32 hash of the parameter 'val'. +--]] + +local string = require("string") +local bit = require("bit") +local tostring = tostring + +module('crc32') + +local CRC32 = { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, + 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, + 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, + 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, + 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, + 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, + 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, + 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, + 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, + 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, + 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, + 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, + 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, + 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, + 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, + 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, + 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, + 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, + 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, + 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, + 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, + 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, + 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, + 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, + 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, + 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, + 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, + 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, + 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, + 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, + 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, + 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, + 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, + 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, + 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, + 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, + 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, + 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, + 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, + 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, + 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, + 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, + 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d +} + +local xor = bit.bxor +local lshift = bit.lshift +local rshift = bit.rshift +local band = bit.band + +function hash(str) + str = tostring(str) + local count = string.len(str) + local crc = 2 ^ 32 - 1 + local i = 1 + + while count > 0 do + local byte = string.byte(str, i) + crc = xor(rshift(crc, 8), CRC32[xor(band(crc, 0xFF), byte) + 1]) + i = i + 1 + count = count - 1 + end + crc = xor(crc, 0xFFFFFFFF) + -- dirty hack for bitop return number < 0 + if crc < 0 then crc = crc + 2 ^ 32 end + + return crc +end + +--[[ +-- the previous one is equvilent to this function but faster +function hash_s(str) + + local i = 1 + local crc = 2 ^ 32 - 1 + local poly = 0xEDB88320 + + for k = string.len(str), 1, -1 do + local byte = string.byte(str, i) + crc = bit.bxor(crc, byte) + for j = 0, 7 do + if bit.band(crc, 1) ~= 0 then + crc = bit.bxor(bit.rshift(crc, 1), poly) + else + crc = bit.rshift(crc, 1) + end + end + i = i + 1 + end + crc = bit.xor(crc, 0xFFFFFFFF) + if crc < 0 then crc = crc + 2 ^ 32 end + + return crc +end +--]] + diff --git a/i_know_my_crc32.lua b/i_know_my_crc32.lua new file mode 100644 index 0000000..dabbae0 --- /dev/null +++ b/i_know_my_crc32.lua @@ -0,0 +1,19 @@ +local crc32 = require 'crc32' +local this_file = 'i_know_my_crc32.lua' + +function read_all(file) + local f = assert(io.open(file, "rb")) + local content = f:read("*all") + f:close() + return content +end + +local content = read_all(this_file) +local crc32_result = crc32.hash(content) +local crc32_expected = '' + +print('My expected crc32 checksum is ' .. crc32_expected) +print('My own crc32 checksum is ' .. crc32_result) + +local match = crc32_result == crc32_expected +return match diff --git a/i_know_my_md5.lua b/i_know_my_md5.lua new file mode 100644 index 0000000..0ef9f0a --- /dev/null +++ b/i_know_my_md5.lua @@ -0,0 +1,19 @@ +local md5 = require 'md5' +local this_file = 'i_know_my_md5.lua' + +function read_all(file) + local f = assert(io.open(file, "rb")) + local content = f:read("*all") + f:close() + return content +end + +local content = read_all(this_file) +local md5_result = md5.sumhexa(content) +local md5_expected = '' + +print('My expected md5 checksum is ' .. md5_expected) +print('My own md5 checksum is ' .. md5_result) + +local match = md5_result == md5_expected +return match