des加密算法.源代码（DES加密算法实验报告）

今天给各位分享des加密算法.源代码的知识，其中也会对DES加密算法实验报告进行解释，如果能碰巧解决你现在面临的问题，别忘了关注本站，现在开始吧！

本文目录一览：

• 1、用c++实现DES的加密解密的源代码
• 2、des算法源代码
• 3、如何利用DES加密的算法保护Java源代码

用c++实现DES的加密解密的源代码

#include iostream

#include fstream

#include bitset

#include string

using namespace std;

bitset64 key;                

bitset48 subKey[16];        

int IP[] = {58, 50, 42, 34, 26, 18, 10, 2,

60, 52, 44, 36, 28, 20, 12, 4,

62, 54, 46, 38, 30, 22, 14, 6,

64, 56, 48, 40, 32, 24, 16, 8,

57, 49, 41, 33, 25, 17, 9,  1,

59, 51, 43, 35, 27, 19, 11, 3,

61, 53, 45, 37, 29, 21, 13, 5,

63, 55, 47, 39, 31, 23, 15, 7};

int IP_1[] = {40, 8, 48, 16, 56, 24, 64, 32,

  39, 7, 47, 15, 55, 23, 63, 31,

  38, 6, 46, 14, 54, 22, 62, 30,

  37, 5, 45, 13, 53, 21, 61, 29,

  36, 4, 44, 12, 52, 20, 60, 28,

  35, 3, 43, 11, 51, 19, 59, 27,

  34, 2, 42, 10, 50, 18, 58, 26,

  33, 1, 41,  9, 49, 17, 57, 25};

int PC_1[] = {57, 49, 41, 33, 25, 17, 9,

   1, 58, 50, 42, 34, 26, 18,

  10,  2, 59, 51, 43, 35, 27,

  19, 11,  3, 60, 52, 44, 36,

  63, 55, 47, 39, 31, 23, 15,

   7, 62, 54, 46, 38, 30, 22,

  14,  6, 61, 53, 45, 37, 29,

  21, 13,  5, 28, 20, 12,  4}; 

int PC_2[] = {14, 17, 11, 24,  1,  5,

   3, 28, 15,  6, 21, 10,

  23, 19, 12,  4, 26,  8,

  16,  7, 27, 20, 13,  2,

  41, 52, 31, 37, 47, 55,

  30, 40, 51, 45, 33, 48,

  44, 49, 39, 56, 34, 53,

  46, 42, 50, 36, 29, 32};

int shiftBits[] = {1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1};

int E[] = {32,  1,  2,  3,  4,  5,

    4,  5,  6,  7,  8,  9,

    8,  9, 10, 11, 12, 13,

   12, 13, 14, 15, 16, 17,

   16, 17, 18, 19, 20, 21,

   20, 21, 22, 23, 24, 25,

   24, 25, 26, 27, 28, 29,

   28, 29, 30, 31, 32,  1};

int S_BOX[8][4][16] = {

{  

{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7},  

{0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8},  

{4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0}, 

{15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13} 

},

{  

{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10},  

{3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5}, 

{0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15},  

{13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9}  

}, 

{  

{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8},  

{13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1},  

{13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7},  

{1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12}  

}, 

{  

{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15},  

{13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9},  

{10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4},  

{3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14}  

},

{  

{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9},  

{14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6},  

{4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14},  

{11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3}  

},

{  

{12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11},  

{10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8},  

{9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6},  

{4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13}  

}, 

{  

{4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1},  

{13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6},  

{1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2},  

{6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12}  

}, 

{  

{13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7},  

{1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2},  

{7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8},  

{2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}  

} 

};

int P[] = {16,  7, 20, 21,

   29, 12, 28, 17,

    1, 15, 23, 26,

    5, 18, 31, 10,

    2,  8, 24, 14,

   32, 27,  3,  9,

   19, 13, 30,  6,

   22, 11,  4, 25 };

bitset32 f(bitset32 R, bitset48 k)

{

bitset48 expandR;

// 第一步：扩展置换，32 - 48

for(int i=0; i48; ++i)

expandR[47-i] = R[32-E[i]];

// 第二步：异或

expandR = expandR ^ k;

// 第三步：查找S_BOX置换表

bitset32 output;

int x = 0;

for(int i=0; i48; i=i+6)

{

int row = expandR[47-i]*2 + expandR[47-i-5];

int col = expandR[47-i-1]*8 + expandR[47-i-2]*4 + expandR[47-i-3]*2 + expandR[47-i-4];

int num = S_BOX[i/6][row][col];

bitset4 binary(num);

output[31-x] = binary[3];

output[31-x-1] = binary[2];

output[31-x-2] = binary[1];

output[31-x-3] = binary[0];

x += 4;

}

// 第四步：P-置换，32 - 32

bitset32 tmp = output;

for(int i=0; i32; ++i)

output[31-i] = tmp[32-P[i]];

return output;

}

bitset28 leftShift(bitset28 k, int shift)

{

bitset28 tmp = k;

for(int i=27; i=0; --i)

{

if(i-shift0)

k[i] = tmp[i-shift+28];

else

k[i] = tmp[i-shift];

}

return k;

}

void generateKeys() 

{

bitset56 realKey;

bitset28 left;

bitset28 right;

bitset48 compressKey;

// 去掉奇偶标记位，将64位密钥变成56位

for (int i=0; i56; ++i)

realKey[55-i] = key[64 - PC_1[i]];

// 生成子密钥，保存在 subKeys[16] 中

for(int round=0; round16; ++round) 

{

// 前28位与后28位

for(int i=28; i56; ++i)

left[i-28] = realKey[i];

for(int i=0; i28; ++i)

right[i] = realKey[i];

// 左移

left = leftShift(left, shiftBits[round]);

right = leftShift(right, shiftBits[round]);

// 压缩置换，由56位得到48位子密钥

for(int i=28; i56; ++i)

realKey[i] = left[i-28];

for(int i=0; i28; ++i)

realKey[i] = right[i];

for(int i=0; i48; ++i)

compressKey[47-i] = realKey[56 - PC_2[i]];

subKey[round] = compressKey;

}

}

bitset64 charToBitset(const char s[8])

{

bitset64 bits;

for(int i=0; i8; ++i)

for(int j=0; j8; ++j)

bits[i*8+j] = ((s[i]j)  1);

return bits;

}

bitset64 encrypt(bitset64 plain)

{

bitset64 cipher;

bitset64 currentBits;

bitset32 left;

bitset32 right;

bitset32 newLeft;

// 第一步：初始置换IP

for(int i=0; i64; ++i)

currentBits[63-i] = plain[64-IP[i]];

// 第二步：获取 Li 和 Ri

for(int i=32; i64; ++i)

left[i-32] = currentBits[i];

for(int i=0; i32; ++i)

right[i] = currentBits[i];

// 第三步：共16轮迭代

for(int round=0; round16; ++round)

{

newLeft = right;

right = left ^ f(right,subKey[round]);

left = newLeft;

}

// 第四步：合并L16和R16，注意合并为 R16L16

for(int i=0; i32; ++i)

cipher[i] = left[i];

for(int i=32; i64; ++i)

cipher[i] = right[i-32];

// 第五步：结尾置换IP-1

currentBits = cipher;

for(int i=0; i64; ++i)

cipher[63-i] = currentBits[64-IP_1[i]];

// 返回密文

return cipher;

}

bitset64 decrypt(bitset64 cipher)

{

bitset64 plain;

bitset64 currentBits;

bitset32 left;

bitset32 right;

bitset32 newLeft;

// 第一步：初始置换IP

for(int i=0; i64; ++i)

currentBits[63-i] = cipher[64-IP[i]];

// 第二步：获取 Li 和 Ri

for(int i=32; i64; ++i)

left[i-32] = currentBits[i];

for(int i=0; i32; ++i)

right[i] = currentBits[i];

// 第三步：共16轮迭代（子密钥逆序应用）

for(int round=0; round16; ++round)

{

newLeft = right;

right = left ^ f(right,subKey[15-round]);

left = newLeft;

}

// 第四步：合并L16和R16，注意合并为 R16L16

for(int i=0; i32; ++i)

plain[i] = left[i];

for(int i=32; i64; ++i)

plain[i] = right[i-32];

// 第五步：结尾置换IP-1

currentBits = plain;

for(int i=0; i64; ++i)

plain[63-i] = currentBits[64-IP_1[i]];

// 返回明文

return plain;

}

int main() {

string s = "romantic";

string k = "12345678";

bitset64 plain = charToBitset(s.c_str());

key = charToBitset(k.c_str());

// 生成16个子密钥

generateKeys();   

bitset64 cipher = encrypt(plain);

fstream file1;

file1.open("D://a.txt", ios::binary | ios::out);

file1.write((char*)cipher,sizeof(cipher));

file1.close();

bitset64 temp;

file1.open("D://a.txt", ios::binary | ios::in);

file1.read((char*)temp, sizeof(temp));

file1.close();

bitset64 temp_plain = decrypt(temp);

file1.open("D://b.txt", ios::binary | ios::out);

file1.write((char*)temp_plain,sizeof(temp_plain));

file1.close();

return 0;

}

des算法源代码

des.h文件：

#ifndef CRYPTOPP_DES_H

#define CRYPTOPP_DES_H

#include "cryptlib.h"

#include "misc.h"

NAMESPACE_BEGIN(CryptoPP)

class DES : public BlockTransformation

{

public:

DES(const byte *userKey, CipherDir);

void ProcessBlock(const byte *inBlock, byte * outBlock) const;

void ProcessBlock(byte * inoutBlock) const

{DES::ProcessBlock(inoutBlock, inoutBlock);}

enum {KEYLENGTH=8, BLOCKSIZE=8};

unsigned int BlockSize() const {return BLOCKSIZE;}

protected:

static const word32 Spbox[8][64];

SecBlockword32 k;

};

class DESEncryption : public DES

{

public:

DESEncryption(const byte * userKey)

: DES (userKey, ENCRYPTION) {}

};

class DESDecryption : public DES

{

public:

DESDecryption(const byte * userKey)

: DES (userKey, DECRYPTION) {}

};

class DES_EDE_Encryption : public BlockTransformation

{

public:

DES_EDE_Encryption(const byte * userKey)

: e(userKey, ENCRYPTION), d(userKey + DES::KEYLENGTH, DECRYPTION) {}

void ProcessBlock(const byte *inBlock, byte * outBlock) const;

void ProcessBlock(byte * inoutBlock) const;

enum {KEYLENGTH=16, BLOCKSIZE=8};

unsigned int BlockSize() const {return BLOCKSIZE;}

private:

DES e, d;

};

class DES_EDE_Decryption : public BlockTransformation

{

public:

DES_EDE_Decryption(const byte * userKey)

: d(userKey, DECRYPTION), e(userKey + DES::KEYLENGTH, ENCRYPTION) {}

void ProcessBlock(const byte *inBlock, byte * outBlock) const;

void ProcessBlock(byte * inoutBlock) const;

enum {KEYLENGTH=16, BLOCKSIZE=8};

unsigned int BlockSize() const {return BLOCKSIZE;}

private:

DES d, e;

};

class TripleDES_Encryption : public BlockTransformation

{

public:

TripleDES_Encryption(const byte * userKey)

: e1(userKey, ENCRYPTION), d(userKey + DES::KEYLENGTH, DECRYPTION),

e2(userKey + 2*DES::KEYLENGTH, ENCRYPTION) {}

void ProcessBlock(const byte *inBlock, byte * outBlock) const;

void ProcessBlock(byte * inoutBlock) const;

enum {KEYLENGTH=24, BLOCKSIZE=8};

unsigned int BlockSize() const {return BLOCKSIZE;}

private:

DES e1, d, e2;

};

class TripleDES_Decryption : public BlockTransformation

{

public:

TripleDES_Decryption(const byte * userKey)

: d1(userKey + 2*DES::KEYLENGTH, DECRYPTION), e(userKey + DES::KEYLENGTH, ENCRYPTION),

d2(userKey, DECRYPTION) {}

void ProcessBlock(const byte *inBlock, byte * outBlock) const;

void ProcessBlock(byte * inoutBlock) const;

enum {KEYLENGTH=24, BLOCKSIZE=8};

unsigned int BlockSize() const {return BLOCKSIZE;}

private:

DES d1, e, d2;

};

NAMESPACE_END

#endif

des.cpp文件：

// des.cpp - modified by Wei Dai from:

/*

* This is a major rewrite of my old public domain DES code written

* circa 1987, which in turn borrowed heavily from Jim Gillogly's 1977

* public domain code. I pretty much kept my key scheduling code, but

* the actual encrypt/decrypt routines are taken from from Richard

* Outerbridge's DES code as printed in Schneier's "Applied Cryptography."

*

* This code is in the public domain. I would appreciate bug reports and

* enhancements.

*

* Phil Karn KA9Q, karn@unix.ka9q.ampr.org, August 1994.

*/

#include "pch.h"

#include "misc.h"

#include "des.h"

NAMESPACE_BEGIN(CryptoPP)

/* Tables defined in the Data Encryption Standard documents

* Three of these tables, the initial permutation, the final

* permutation and the expansion operator, are regular enough that

* for speed, we hard-code them. They're here for reference only.

* Also, the S and P boxes are used by a separate program, gensp.c,

* to build the combined SP box, Spbox[]. They're also here just

* for reference.

*/

#ifdef notdef

/* initial permutation IP */

static byte ip[] = {

58, 50, 42, 34, 26, 18, 10, 2,

60, 52, 44, 36, 28, 20, 12, 4,

62, 54, 46, 38, 30, 22, 14, 6,

64, 56, 48, 40, 32, 24, 16, 8,

57, 49, 41, 33, 25, 17, 9, 1,

59, 51, 43, 35, 27, 19, 11, 3,

61, 53, 45, 37, 29, 21, 13, 5,

63, 55, 47, 39, 31, 23, 15, 7

};

/* final permutation IP^-1 */

static byte fp[] = {

40, 8, 48, 16, 56, 24, 64, 32,

39, 7, 47, 15, 55, 23, 63, 31,

38, 6, 46, 14, 54, 22, 62, 30,

37, 5, 45, 13, 53, 21, 61, 29,

36, 4, 44, 12, 52, 20, 60, 28,

35, 3, 43, 11, 51, 19, 59, 27,

34, 2, 42, 10, 50, 18, 58, 26,

33, 1, 41, 9, 49, 17, 57, 25

};

/* expansion operation matrix */

static byte ei[] = {

32, 1, 2, 3, 4, 5,

4, 5, 6, 7, 8, 9,

8, 9, 10, 11, 12, 13,

12, 13, 14, 15, 16, 17,

16, 17, 18, 19, 20, 21,

20, 21, 22, 23, 24, 25,

24, 25, 26, 27, 28, 29,

28, 29, 30, 31, 32, 1

};

/* The (in)famous S-boxes */

static byte sbox[8][64] = {

/* S1 */

14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,

0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,

4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,

15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13,

/* S2 */

15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,

3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,

0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,

13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9,

/* S3 */

10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,

13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,

13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,

1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12,

/* S4 */

7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,

13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,

10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,

3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14,

/* S5 */

2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,

14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,

4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,

11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3,

/* S6 */

12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,

10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,

9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,

4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13,

/* S7 */

4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,

13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,

1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,

6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12,

/* S8 */

13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,

1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,

7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,

2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11

};

/* 32-bit permutation function P used on the output of the S-boxes */

static byte p32i[] = {

16, 7, 20, 21,

29, 12, 28, 17,

1, 15, 23, 26,

5, 18, 31, 10,

2, 8, 24, 14,

32, 27, 3, 9,

19, 13, 30, 6,

22, 11, 4, 25

};

#endif

/* permuted choice table (key) */

static const byte pc1[] = {

57, 49, 41, 33, 25, 17, 9,

1, 58, 50, 42, 34, 26, 18,

10, 2, 59, 51, 43, 35, 27,

19, 11, 3, 60, 52, 44, 36,

63, 55, 47, 39, 31, 23, 15,

7, 62, 54, 46, 38, 30, 22,

14, 6, 61, 53, 45, 37, 29,

21, 13, 5, 28, 20, 12, 4

};

/* number left rotations of pc1 */

static const byte totrot[] = {

1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28

};

/* permuted choice key (table) */

static const byte pc2[] = {

14, 17, 11, 24, 1, 5,

3, 28, 15, 6, 21, 10,

23, 19, 12, 4, 26, 8,

16, 7, 27, 20, 13, 2,

41, 52, 31, 37, 47, 55,

30, 40, 51, 45, 33, 48,

44, 49, 39, 56, 34, 53,

46, 42, 50, 36, 29, 32

};

/* End of DES-defined tables */

/* bit 0 is left-most in byte */

static const int bytebit[] = {

0200,0100,040,020,010,04,02,01

};

/* Set key (initialize key schedule array) */

DES::DES(const byte *key, CipherDir dir)

: k(32)

{

SecByteBlock buffer(56+56+8);

byte *const pc1m=buffer; /* place to modify pc1 into */

byte *const pcr=pc1m+56; /* place to rotate pc1 into */

byte *const ks=pcr+56;

register int i,j,l;

int m;

for (j=0; j56; j++) { /* convert pc1 to bits of key */

l=pc1[j]-1; /* integer bit location */

m = l 07; /* find bit */

pc1m[j]=(key[l3] /* find which key byte l is in */

bytebit[m]) /* and which bit of that byte */

? 1 : 0; /* and store 1-bit result */

}

for (i=0; i16; i++) { /* key chunk for each iteration */

memset(ks,0,8); /* Clear key schedule */

for (j=0; j56; j++) /* rotate pc1 the right amount */

pcr[j] = pc1m[(l=j+totrot[i])(j28? 28 : 56) ? l: l-28];

/* rotate left and right halves independently */

for (j=0; j48; j++){ /* select bits individually */

/* check bit that goes to ks[j] */

if (pcr[pc2[j]-1]){

/* mask it in if it's there */

l= j % 6;

ks[j/6] |= bytebit[l] 2;

}

}

/* Now convert to odd/even interleaved form for use in F */

k[2*i] = ((word32)ks[0] 24)

| ((word32)ks[2] 16)

| ((word32)ks[4] 8)

| ((word32)ks[6]);

k[2*i+1] = ((word32)ks[1] 24)

| ((word32)ks[3] 16)

| ((word32)ks[5] 8)

| ((word32)ks[7]);

}

if (dir==DECRYPTION) // reverse key schedule order

for (i=0; i16; i+=2)

{

std::swap(k[i], k[32-2-i]);

std::swap(k[i+1], k[32-1-i]);

}

}

/* End of C code common to both versions */

/* C code only in portable version */

// Richard Outerbridge's initial permutation algorithm

/*

inline void IPERM(word32 left, word32 right)

{

word32 work;

work = ((left 4) ^ right) 0x0f0f0f0f;

right ^= work;

left ^= work 4;

work = ((left 16) ^ right) 0xffff;

right ^= work;

left ^= work 16;

work = ((right 2) ^ left) 0x33333333;

left ^= work;

right ^= (work 2);

work = ((right 8) ^ left) 0xff00ff;

left ^= work;

right ^= (work 8);

right = rotl(right, 1);

work = (left ^ right) 0xaaaaaaaa;

left ^= work;

right ^= work;

left = rotl(left, 1);

}

inline void FPERM(word32 left, word32 right)

{

word32 work;

right = rotr(right, 1);

work = (left ^ right) 0xaaaaaaaa;

left ^= work;

right ^= work;

left = rotr(left, 1);

work = ((left 8) ^ right) 0xff00ff;

right ^= work;

left ^= work 8;

work = ((left 2) ^ right) 0x33333333;

right ^= work;

left ^= work 2;

work = ((right 16) ^ left) 0xffff;

left ^= work;

right ^= work 16;

work = ((right 4) ^ left) 0x0f0f0f0f;

left ^= work;

right ^= work 4;

}

*/

// Wei Dai's modification to Richard Outerbridge's initial permutation

// algorithm, this one is faster if you have access to rotate instructions

// (like in MSVC)

inline void IPERM(word32 left, word32 right)

{

word32 work;

right = rotl(right, 4U);

work = (left ^ right) 0xf0f0f0f0;

left ^= work;

right = rotr(right^work, 20U);

work = (left ^ right) 0xffff0000;

left ^= work;

right = rotr(right^work, 18U);

work = (left ^ right) 0x33333333;

left ^= work;

right = rotr(right^work, 6U);

work = (left ^ right) 0x00ff00ff;

left ^= work;

right = rotl(right^work, 9U);

work = (left ^ right) 0xaaaaaaaa;

left = rotl(left^work, 1U);

right ^= work;

}

inline void FPERM(word32 left, word32 right)

{

word32 work;

right = rotr(right, 1U);

work = (left ^ right) 0xaaaaaaaa;

right ^= work;

left = rotr(left^work, 9U);

work = (left ^ right) 0x00ff00ff;

right ^= work;

left = rotl(left^work, 6U);

work = (left ^ right) 0x33333333;

right ^= work;

left = rotl(left^work, 18U);

work = (left ^ right) 0xffff0000;

right ^= work;

left = rotl(left^work, 20U);

work = (left ^ right) 0xf0f0f0f0;

right ^= work;

left = rotr(left^work, 4U);

}

// Encrypt or decrypt a block of data in ECB mode

void DES::ProcessBlock(const byte *inBlock, byte * outBlock) const

{

word32 l,r,work;

#ifdef IS_LITTLE_ENDIAN

l = byteReverse(*(word32 *)inBlock);

r = byteReverse(*(word32 *)(inBlock+4));

#else

l = *(word32 *)inBlock;

r = *(word32 *)(inBlock+4);

#endif

IPERM(l,r);

const word32 *kptr=k;

for (unsigned i=0; i8; i++)

{

work = rotr(r, 4U) ^ kptr[4*i+0];

l ^= Spbox[6][(work) 0x3f]

^ Spbox[4][(work 8) 0x3f]

^ Spbox[2][(work 16) 0x3f]

^ Spbox[0][(work 24) 0x3f];

work = r ^ kptr[4*i+1];

l ^= Spbox[7][(work) 0x3f]

^ Spbox[5][(work 8) 0x3f]

^ Spbox[3][(work 16) 0x3f]

^ Spbox[1][(work 24) 0x3f];

work = rotr(l, 4U) ^ kptr[4*i+2];

r ^= Spbox[6][(work) 0x3f]

^ Spbox[4][(work 8) 0x3f]

^ Spbox[2][(work 16) 0x3f]

^ Spbox[0][(work 24) 0x3f];

work = l ^ kptr[4*i+3];

r ^= Spbox[7][(work) 0x3f]

^ Spbox[5][(work 8) 0x3f]

^ Spbox[3][(work 16) 0x3f]

^ Spbox[1][(work 24) 0x3f];

}

FPERM(l,r);

#ifdef IS_LITTLE_ENDIAN

*(word32 *)outBlock = byteReverse(r);

*(word32 *)(outBlock+4) = byteReverse(l);

#else

*(word32 *)outBlock = r;

*(word32 *)(outBlock+4) = l;

#endif

}

void DES_EDE_Encryption::ProcessBlock(byte *inoutBlock) const

{

e.ProcessBlock(inoutBlock);

d.ProcessBlock(inoutBlock);

e.ProcessBlock(inoutBlock);

}

void DES_EDE_Encryption::ProcessBlock(const byte *inBlock, byte *outBlock) const

{

e.ProcessBlock(inBlock, outBlock);

d.ProcessBlock(outBlock);

e.ProcessBlock(outBlock);

}

void DES_EDE_Decryption::ProcessBlock(byte *inoutBlock) const

{

d.ProcessBlock(inoutBlock);

e.ProcessBlock(inoutBlock);

d.ProcessBlock(inoutBlock);

}

void DES_EDE_Decryption::ProcessBlock(const byte *inBlock, byte *outBlock) const

{

d.ProcessBlock(inBlock, outBlock);

e.ProcessBlock(outBlock);

d.ProcessBlock(outBlock);

}

void TripleDES_Encryption::ProcessBlock(byte *inoutBlock) const

{

e1.ProcessBlock(inoutBlock);

d.ProcessBlock(inoutBlock);

e2.ProcessBlock(inoutBlock);

}

void TripleDES_Encryption::ProcessBlock(const byte *inBlock, byte *outBlock) const

{

e1.ProcessBlock(inBlock, outBlock);

d.ProcessBlock(outBlock);

e2.ProcessBlock(outBlock);

}

void TripleDES_Decryption::ProcessBlock(byte *inoutBlock) const

{

d1.ProcessBlock(inoutBlock);

e.ProcessBlock(inoutBlock);

d2.ProcessBlock(inoutBlock);

}

void TripleDES_Decryption::ProcessBlock(const byte *inBlock, byte *outBlock) const

{

d1.ProcessBlock(inBlock, outBlock);

e.ProcessBlock(outBlock);

d2.ProcessBlock(outBlock);

}

NAMESPACE_END

如何利用DES加密的算法保护Java源代码

Java语言是一种非常适用于网络编程的语言，它的基本结构与C++极为相似，但抛弃了C/C++中指针等内容，同时它吸收了Smalltalk、C++面向对象的编程思想。它具有简单性、鲁棒性、可移植性、动态性等特点。这些特点使得Java成为跨平台应用开发的一种规范，在世界范围内广泛流传。 加密Java源码的原因 Java源代码经过编译以后在JVM中执行。由于JVM界面是完全透明的，Java类文件能够很容易通过反编译器重新转换成源代码。因此，所有的算法、类文件等都可以以源代码的形式被公开，使得软件不能受到保护，为了保护产权，一般可以有以下几种方法： (1)"模糊"类文件，加大反编译器反编译源代码文件的难度。然而，可以修改反编译器，使之能够处理这些模糊类文件。所以仅仅依赖"模糊类文件"来保证代码的安全是不够的。 (2)流行的加密工具对源文件进行加密，比如PGP(Pretty Good Privacy)或GPG(GNU Privacy Guard)。这时，最终用户在运行应用之前必须先进行解密。但解密之后，最终用户就有了一份不加密的类文件，这和事先不进行加密没有什么差别。 (3)加密类文件，在运行中JVM用定制的类装载器(Class Loader)解密类文件。Java运行时装入字节码的机制隐含地意味着可以对字节码进行修改。JVM每次装入类文件时都需要一个称为ClassLoader的对象，这个对象负责把新的类装入正在运行的JVM。JVM给ClassLoader一个包含了待装入类(例如java.lang.Object)名字的字符串，然后由ClassLoader负责找到类文件，装入原始数据，并把它转换成一个Class对象。 用户下载的是加密过的类文件，在加密类文件装入之时进行解密，因此可以看成是一种即时解密器。由于解密后的字节码文件永远不会保存到文件系统，所以窃密者很难得到解密后的代码。 由于把原始字节码转换成Class对象的过程完全由系统负责，所以创建定制ClassLoader对象其实并不困难，只需先获得原始数据，接着就可以进行包含解密在内的任何转换。 Java密码体系和Java密码扩展 Java密码体系(JCA)和Java密码扩展(JCE)的设计目的是为Java提供与实现无关的加密函数API。它们都用factory方法来创建类的例程，然后把实际的加密函数委托给提供者指定的底层引擎,引擎中为类提供了服务提供者接口在Java中实现数据的加密/解密，是使用其内置的JCE(Java加密扩展)来实现的。Java开发工具集1.1为实现包括数字签名和信息摘要在内的加密功能，推出了一种基于供应商的新型灵活应用编程接口。Java密码体系结构支持供应商的互操作,同时支持硬件和软件实现。 Java密码学结构设计遵循两个原则: (1)算法的独立性和可靠性。 (2)实现的独立性和相互作用性。 算法的独立性是通过定义密码服务类来获得。用户只需了解密码算法的概念,而不用去关心如何实现这些概念。实现的独立性和相互作用性通过密码服务提供器来实现。密码服务提供器是实现一个或多个密码服务的一个或多个程序包。软件开发商根据一定接口,将各种算法实现后,打包成一个提供器,用户可以安装不同的提供器。安装和配置提供器,可将包含提供器的ZIP和JAR文件放在CLASSPATH下,再编辑Java安全属性文件来设置定义一个提供器。Java运行环境Sun版本时, 提供一个缺省的提供器Sun。 下面介绍DES算法及如何利用DES算法加密和解密类文件的步骤。 DES算法简介 DES(Data Encryption Standard)是发明最早的最广泛使用的分组对称加密算法。DES算法的入口参数有三个：Key、Data、Mode。

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