protectsmx.cpp

#include "protectsmx.h"

#include <cstring>
#include <algorithm>

#include <stdint.h>
#include <cstddef>
#include <vector>
#include <memory>

#include <am-utility.h>
#include <smx/smx-headers.h>

using namespace sp;


std::vector<char> KEY({
	0x5F,0x3B,0x35,0x2E,0x5D,0x39,0x34,0x2D,0x33,
	0x31,0x3D,0x3D,0x2D,0x25,0x78,0x54,0x21,0x5E,
	0x5B,0x24,0x00
});


enum class FileType {
  UNKNOWN,
  AMX,
  AMXMODX,
  SPFF
};

FileType DetectFileType(FILE *fp);

class FileReader
{
 public:
  explicit FileReader(FILE *fp);
  FileReader(std::unique_ptr<uint8_t[]> &buffer, size_t length);

  const uint8_t *buffer() const {
	return buffer_.get();
  }
  size_t length() const {
	return length_;
  }

 protected:
  std::unique_ptr<uint8_t[]> buffer_;
  size_t length_;
};


#ifndef __blowfish__
#define __blowfish__

class Blowfish {
public:
  explicit Blowfish(const std::vector<char> &key);
  std::vector<char> Encrypt(const std::vector<char> &src) const;
  std::vector<char> Decrypt(const std::vector<char> &src) const;

private:
  void SetKey(const char *key, size_t byte_length);
  void EncryptBlock(uint32_t *left, uint32_t *right) const;
  void DecryptBlock(uint32_t *left, uint32_t *right) const;
  uint32_t Feistel(uint32_t value) const;

private:
  uint32_t pary_[18];
  uint32_t sbox_[4][256];
};

#endif /* defined(__blowfish__) */



FILE* protect_read_smx(const char* file, const char* mode)
{
	FILE *fp = fopen(file, "rb");
	if (!fp) return fp;

	FILE *plugin_fp;
	Blowfish bfengine(KEY);

	FileType ftype = DetectFileType(fp);
	FileReader reader(fp);
	fclose(fp);

	const char *buffer = reinterpret_cast<const char *>(reader.buffer());
	std::vector<char> content(buffer, buffer + reader.length());

	if (ftype == FileType::UNKNOWN)
	{
		// Скорее всего файл был ранее нами зашифрован
		// Расшифровываем и возвращаем плагин

		auto&& encrypted = content;

		auto decrypted = bfengine.Decrypt(encrypted);

		auto decrypted_size = decrypted.size();
		char* result = (char*)malloc(decrypted_size);
		std::copy(decrypted.begin(), decrypted.end(), result);

		plugin_fp = fmemopen(result, decrypted_size, mode);
	}
	else
	{
		// Плагин не зашифрован, шифруем его на диске
		// и возвращаем незашифрованную копию

		auto&& decrypted = content;

		auto encrypted = bfengine.Encrypt(decrypted);
		fp = fopen(file, "wb");
		fwrite(encrypted.data(), sizeof(char), encrypted.size(), fp);
		fclose(fp);

		auto decrypted_size = decrypted.size();
		char* result = (char*)malloc(decrypted_size);
		std::copy(decrypted.begin(), decrypted.end(), result);

		plugin_fp = fmemopen(result, decrypted_size, mode);
	}

	return plugin_fp;
}



FileType
DetectFileType(FILE *fp)
{
  uint32_t magic = 0;
  if (fread(&magic, sizeof(uint32_t), 1, fp) != 1)
	return FileType::UNKNOWN;

  if (magic == SmxConsts::FILE_MAGIC)
	return FileType::SPFF;

  return FileType::UNKNOWN;
}

FileReader::FileReader(FILE *fp)
 : length_(0)
{
  if (fseek(fp, 0, SEEK_END) != 0)
	return;
  long size = ftell(fp);
  if (size < 0)
	return;
  if (fseek(fp, 0, SEEK_SET) != 0)
	return;

  std::unique_ptr<uint8_t[]> bytes(new uint8_t[size]);
  if (!bytes || fread(bytes.get(), sizeof(uint8_t), size, fp) != (size_t)size)
	return;

  buffer_ = std::move(bytes);
  length_ = size;
}

FileReader::FileReader(std::unique_ptr<uint8_t[]> &buffer, size_t length)
 : buffer_(std::move(buffer)),
   length_(length)
{
}

/* BLOWFISH ENCRYPT ALGORITHM  */


#if !defined(__LITTLE_ENDIAN__) and !defined(__BIG_ENDIAN__)
#define __LITTLE_ENDIAN__
#endif

namespace {

union Converter32 {
  uint32_t bit_32;
  struct {

#ifdef __LITTLE_ENDIAN__
	uint8_t byte3;
	uint8_t byte2;
	uint8_t byte1;
	uint8_t byte0;
#else
	uint8_t byte0;
	uint8_t byte1;
	uint8_t byte2;
	uint8_t byte3;
#endif

  } bit_8;
};

const uint32_t initial_pary[18] = {
	0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344, 0xa4093822, 0x299f31d0,
	0x082efa98, 0xec4e6c89, 0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c,
	0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917, 0x9216d5d9, 0x8979fb1b};

const uint32_t initial_sbox[4][256] = {
	{0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7, 0xb8e1afed, 0x6a267e96,
	 0xba7c9045, 0xf12c7f99, 0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16,
	 0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e, 0x0d95748f, 0x728eb658,
	 0x718bcd58, 0x82154aee, 0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013,
	 0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef, 0x8e79dcb0, 0x603a180e,
	 0x6c9e0e8b, 0xb01e8a3e, 0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60,
	 0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440, 0x55ca396a, 0x2aab10b6,
	 0xb4cc5c34, 0x1141e8ce, 0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a,
	 0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e, 0xafd6ba33, 0x6c24cf5c,
	 0x7a325381, 0x28958677, 0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193,
	 0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032, 0xef845d5d, 0xe98575b1,
	 0xdc262302, 0xeb651b88, 0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239,
	 0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e, 0x21c66842, 0xf6e96c9a,
	 0x670c9c61, 0xabd388f0, 0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3,
	 0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98, 0xa1f1651d, 0x39af0176,
	 0x66ca593e, 0x82430e88, 0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe,
	 0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6, 0x4ed3aa62, 0x363f7706,
	 0x1bfedf72, 0x429b023d, 0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b,
	 0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7, 0xe3fe501a, 0xb6794c3b,
	 0x976ce0bd, 0x04c006ba, 0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463,
	 0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f, 0x6dfc511f, 0x9b30952c,
	 0xcc814544, 0xaf5ebd09, 0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3,
	 0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb, 0x5579c0bd, 0x1a60320a,
	 0xd6a100c6, 0x402c7279, 0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8,
	 0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab, 0x323db5fa, 0xfd238760,
	 0x53317b48, 0x3e00df82, 0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db,
	 0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573, 0x695b27b0, 0xbbca58c8,
	 0xe1ffa35d, 0xb8f011a0, 0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b,
	 0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790, 0xe1ddf2da, 0xa4cb7e33,
	 0x62fb1341, 0xcee4c6e8, 0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4,
	 0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0, 0xd08ed1d0, 0xafc725e0,
	 0x8e3c5b2f, 0x8e7594b7, 0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c,
	 0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad, 0x2f2f2218, 0xbe0e1777,
	 0xea752dfe, 0x8b021fa1, 0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299,
	 0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9, 0x165fa266, 0x80957705,
	 0x93cc7314, 0x211a1477, 0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf,
	 0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49, 0x00250e2d, 0x2071b35e,
	 0x226800bb, 0x57b8e0af, 0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa,
	 0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5, 0x83260376, 0x6295cfa9,
	 0x11c81968, 0x4e734a41, 0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915,
	 0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400, 0x08ba6fb5, 0x571be91f,
	 0xf296ec6b, 0x2a0dd915, 0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664,
	 0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a},
	{0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623, 0xad6ea6b0, 0x49a7df7d,
	 0x9cee60b8, 0x8fedb266, 0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1,
	 0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e, 0x3f54989a, 0x5b429d65,
	 0x6b8fe4d6, 0x99f73fd6, 0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1,
	 0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e, 0x09686b3f, 0x3ebaefc9,
	 0x3c971814, 0x6b6a70a1, 0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737,
	 0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8, 0xb03ada37, 0xf0500c0d,
	 0xf01c1f04, 0x0200b3ff, 0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd,
	 0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701, 0x3ae5e581, 0x37c2dadc,
	 0xc8b57634, 0x9af3dda7, 0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41,
	 0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331, 0x4e548b38, 0x4f6db908,
	 0x6f420d03, 0xf60a04bf, 0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af,
	 0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e, 0x5512721f, 0x2e6b7124,
	 0x501adde6, 0x9f84cd87, 0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c,
	 0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2, 0xef1c1847, 0x3215d908,
	 0xdd433b37, 0x24c2ba16, 0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd,
	 0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b, 0x043556f1, 0xd7a3c76b,
	 0x3c11183b, 0x5924a509, 0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e,
	 0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3, 0x771fe71c, 0x4e3d06fa,
	 0x2965dcb9, 0x99e71d0f, 0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a,
	 0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4, 0xf2f74ea7, 0x361d2b3d,
	 0x1939260f, 0x19c27960, 0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66,
	 0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28, 0xc332ddef, 0xbe6c5aa5,
	 0x65582185, 0x68ab9802, 0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84,
	 0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510, 0x13cca830, 0xeb61bd96,
	 0x0334fe1e, 0xaa0363cf, 0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14,
	 0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e, 0x648b1eaf, 0x19bdf0ca,
	 0xa02369b9, 0x655abb50, 0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7,
	 0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8, 0xf837889a, 0x97e32d77,
	 0x11ed935f, 0x16681281, 0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99,
	 0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696, 0xcdb30aeb, 0x532e3054,
	 0x8fd948e4, 0x6dbc3128, 0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73,
	 0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0, 0x45eee2b6, 0xa3aaabea,
	 0xdb6c4f15, 0xfacb4fd0, 0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105,
	 0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250, 0xcf62a1f2, 0x5b8d2646,
	 0xfc8883a0, 0xc1c7b6a3, 0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285,
	 0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00, 0x58428d2a, 0x0c55f5ea,
	 0x1dadf43e, 0x233f7061, 0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb,
	 0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e, 0xa6078084, 0x19f8509e,
	 0xe8efd855, 0x61d99735, 0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc,
	 0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9, 0xdb73dbd3, 0x105588cd,
	 0x675fda79, 0xe3674340, 0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20,
	 0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7},
	{0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934, 0x411520f7, 0x7602d4f7,
	 0xbcf46b2e, 0xd4a20068, 0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af,
	 0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840, 0x4d95fc1d, 0x96b591af,
	 0x70f4ddd3, 0x66a02f45, 0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504,
	 0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a, 0x28507825, 0x530429f4,
	 0x0a2c86da, 0xe9b66dfb, 0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee,
	 0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6, 0xaace1e7c, 0xd3375fec,
	 0xce78a399, 0x406b2a42, 0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b,
	 0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2, 0x3a6efa74, 0xdd5b4332,
	 0x6841e7f7, 0xca7820fb, 0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527,
	 0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b, 0x55a867bc, 0xa1159a58,
	 0xcca92963, 0x99e1db33, 0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c,
	 0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3, 0x95c11548, 0xe4c66d22,

	 0x48c1133f, 0xc70f86dc, 0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17,
	 0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564, 0x257b7834, 0x602a9c60,
	 0xdff8e8a3, 0x1f636c1b, 0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115,
	 0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922, 0x85b2a20e, 0xe6ba0d99,
	 0xde720c8c, 0x2da2f728, 0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0,
	 0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e, 0x0a476341, 0x992eff74,
	 0x3a6f6eab, 0xf4f8fd37, 0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d,
	 0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804, 0xf1290dc7, 0xcc00ffa3,
	 0xb5390f92, 0x690fed0b, 0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3,
	 0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb, 0x37392eb3, 0xcc115979,
	 0x8026e297, 0xf42e312d, 0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c,
	 0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350, 0x1a6b1018, 0x11caedfa,
	 0x3d25bdd8, 0xe2e1c3c9, 0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a,
	 0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe, 0x9dbc8057, 0xf0f7c086,
	 0x60787bf8, 0x6003604d, 0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc,
	 0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f, 0x77a057be, 0xbde8ae24,
	 0x55464299, 0xbf582e61, 0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2,
	 0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9, 0x7aeb2661, 0x8b1ddf84,
	 0x846a0e79, 0x915f95e2, 0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c,
	 0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e, 0xb77f19b6, 0xe0a9dc09,
	 0x662d09a1, 0xc4324633, 0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10,
	 0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169, 0xdcb7da83, 0x573906fe,
	 0xa1e2ce9b, 0x4fcd7f52, 0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027,
	 0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5, 0xf0177a28, 0xc0f586e0,
	 0x006058aa, 0x30dc7d62, 0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634,
	 0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76, 0x6f05e409, 0x4b7c0188,
	 0x39720a3d, 0x7c927c24, 0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc,
	 0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4, 0x1e50ef5e, 0xb161e6f8,
	 0xa28514d9, 0x6c51133c, 0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837,
	 0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0},
	{0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b, 0x5cb0679e, 0x4fa33742,
	 0xd3822740, 0x99bc9bbe, 0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b,
	 0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4, 0x5748ab2f, 0xbc946e79,
	 0xc6a376d2, 0x6549c2c8, 0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6,
	 0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304, 0xa1fad5f0, 0x6a2d519a,
	 0x63ef8ce2, 0x9a86ee22, 0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4,
	 0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6, 0x2826a2f9, 0xa73a3ae1,
	 0x4ba99586, 0xef5562e9, 0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59,
	 0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593, 0xe990fd5a, 0x9e34d797,
	 0x2cf0b7d9, 0x022b8b51, 0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28,
	 0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c, 0xe029ac71, 0xe019a5e6,
	 0x47b0acfd, 0xed93fa9b, 0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28,
	 0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c, 0x15056dd4, 0x88f46dba,
	 0x03a16125, 0x0564f0bd, 0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a,
	 0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319, 0x7533d928, 0xb155fdf5,
	 0x03563482, 0x8aba3cbb, 0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f,
	 0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991, 0xea7a90c2, 0xfb3e7bce,
	 0x5121ce64, 0x774fbe32, 0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680,
	 0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166, 0xb39a460a, 0x6445c0dd,
	 0x586cdecf, 0x1c20c8ae, 0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb,
	 0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5, 0x72eacea8, 0xfa6484bb,
	 0x8d6612ae, 0xbf3c6f47, 0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370,
	 0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d, 0x4040cb08, 0x4eb4e2cc,
	 0x34d2466a, 0x0115af84, 0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048,
	 0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8, 0x611560b1, 0xe7933fdc,
	 0xbb3a792b, 0x344525bd, 0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9,
	 0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7, 0x1a908749, 0xd44fbd9a,
	 0xd0dadecb, 0xd50ada38, 0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f,
	 0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c, 0xbf97222c, 0x15e6fc2a,
	 0x0f91fc71, 0x9b941525, 0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1,
	 0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442, 0xe0ec6e0e, 0x1698db3b,
	 0x4c98a0be, 0x3278e964, 0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e,
	 0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8, 0xdf359f8d, 0x9b992f2e,
	 0xe60b6f47, 0x0fe3f11d, 0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f,
	 0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299, 0xf523f357, 0xa6327623,
	 0x93a83531, 0x56cccd02, 0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc,
	 0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614, 0xe6c6c7bd, 0x327a140a,
	 0x45e1d006, 0xc3f27b9a, 0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6,
	 0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b, 0x53113ec0, 0x1640e3d3,
	 0x38abbd60, 0x2547adf0, 0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060,
	 0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e, 0x1948c25c, 0x02fb8a8c,
	 0x01c36ae4, 0xd6ebe1f9, 0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f,
	 0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6}};

unsigned long GCD(unsigned long larger, unsigned long smaller) {
  unsigned long gcd = smaller;
  unsigned long gcd_prev = larger;
  unsigned long gcd_next;

  while ((gcd_next = gcd_prev % gcd) != 0) {
	gcd_prev = gcd;
	gcd = gcd_next;
  }

  return gcd;
}

size_t PKCS5PaddingLength(const std::vector<char> &data) {
  if (data.empty())
	return 0;
  char length = data[data.size() - 1];
  if (length > 0 && length <= 8) {
	for (size_t i = 0; i < length; ++i) {
	  if (length != data[data.size() - i - 1]) {
		return 0;
	  }
	}
  } else {
	return 0;
  }
  return length;
}

}; // anonymous namespace

Blowfish::Blowfish(const std::vector<char> &key) {
  SetKey(key.data(), key.size());
}

void Blowfish::SetKey(const char *key, size_t byte_length) {
  std::memcpy(pary_, initial_pary, sizeof(initial_pary));
  std::memcpy(sbox_, initial_sbox, sizeof(initial_sbox));

  static const int pary_length = sizeof(pary_) / sizeof(uint32_t);
  static const int sbox_length = sizeof(sbox_) / sizeof(uint32_t);

  {
	unsigned long buffer_length =
		byte_length / GCD(byte_length, sizeof(uint32_t));
	uint32_t *key_buffer = new uint32_t[buffer_length];

	for (unsigned long i = 0; i < buffer_length; ++i) {
	  Converter32 converter;

	  converter.bit_8.byte0 = key[(i * 4) % byte_length];
	  converter.bit_8.byte1 = key[(i * 4 + 1) % byte_length];
	  converter.bit_8.byte2 = key[(i * 4 + 2) % byte_length];
	  converter.bit_8.byte3 = key[(i * 4 + 3) % byte_length];

	  key_buffer[i] = converter.bit_32;
	}

	for (int i = 0; i < pary_length; ++i) {
	  uint32_t key_uint32 = key_buffer[i % buffer_length];
	  pary_[i] ^= key_uint32;
	}

	delete[] key_buffer;
  }

  uint32_t left = 0x00000000;
  uint32_t right = 0x00000000;

  for (int i = 0; i < (pary_length / 2); ++i) {
	EncryptBlock(&left, &right);

	pary_[i * 2] = left;
	pary_[i * 2 + 1] = right;
  }

  for (int i = 0; i < (sbox_length / 2); ++i) {
	EncryptBlock(&left, &right);

	reinterpret_cast<uint32_t *>(sbox_)[i * 2] = left;
	reinterpret_cast<uint32_t *>(sbox_)[i * 2 + 1] = right;
  }
}

std::vector<char> Blowfish::Encrypt(const std::vector<char> &src) const {
  std::vector<char> dst = src;

  size_t padding_length = dst.size() % sizeof(uint64_t);
  if (padding_length == 0) {
	padding_length = sizeof(uint64_t);
  } else {
	padding_length = sizeof(uint64_t) - padding_length;
  }

  for (size_t i = 0; i < padding_length; ++i) {
	dst.push_back(static_cast<char>(padding_length));
  }

  for (int i = 0; i < dst.size() / sizeof(uint64_t); ++i) {
	uint32_t *left = &reinterpret_cast<uint32_t *>(dst.data())[i * 2];
	uint32_t *right = &reinterpret_cast<uint32_t *>(dst.data())[i * 2 + 1];
	EncryptBlock(left, right);
  }

  return dst;
}

std::vector<char> Blowfish::Decrypt(const std::vector<char> &src) const {
  std::vector<char> dst = src;

  for (int i = 0; i < dst.size() / sizeof(uint64_t); ++i) {
	uint32_t *left = &reinterpret_cast<uint32_t *>(dst.data())[i * 2];
	uint32_t *right = &reinterpret_cast<uint32_t *>(dst.data())[i * 2 + 1];
	DecryptBlock(left, right);
  }

  size_t padding_length = PKCS5PaddingLength(dst);
  dst.resize(dst.size() - padding_length);
  return dst;
}

void Blowfish::EncryptBlock(uint32_t *left, uint32_t *right) const {
  for (int i = 0; i < 16; ++i) {
	*left ^= pary_[i];
	*right ^= Feistel(*left);
	std::swap(*left, *right);
  }

  std::swap(*left, *right);

  *right ^= pary_[16];
  *left ^= pary_[17];
}

void Blowfish::DecryptBlock(uint32_t *left, uint32_t *right) const {
  for (int i = 0; i < 16; ++i) {
	*left ^= pary_[17 - i];
	*right ^= Feistel(*left);
	std::swap(*left, *right);
  }

  std::swap(*left, *right);

  *right ^= pary_[1];
  *left ^= pary_[0];
}

uint32_t Blowfish::Feistel(uint32_t value) const {
  Converter32 converter;
  converter.bit_32 = value;

  uint8_t a = converter.bit_8.byte0;
  uint8_t b = converter.bit_8.byte1;
  uint8_t c = converter.bit_8.byte2;
  uint8_t d = converter.bit_8.byte3;

  return ((sbox_[0][a] + sbox_[1][b]) ^ sbox_[2][c]) + sbox_[3][d];
}