DES对称加密算法（密码学）

/* 名称：DES对称加密算法实现过程 */ /* * */ #include < bitset > #include < vector > #include < string > #include < iostream > using namespace std; //using namespace gy; //二进制序列 typedef bitset< 4 > _b4; typedef bitset< 6 > _b6; typedef bitset< 8 > _b8; typedef bitset< 28 > _b28; typedef bitset< 32 > _b32; typedef bitset< 48 > _b48; typedef bitset< 56 > _b56; typedef bitset< 64 > _b64; typedef vector< _b8 > _vb8; typedef vector< _b48 > _vb48; typedef vector< _b64 > _vb64; namespace { //64位密钥 去掉奇偶校验位获得56位 const int keyperm_table56[56] = { 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 }; //56位密码压缩--48位 const int keycompperm_table[48] = { 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 }; //密钥移位表 const int keyshift_table[16] = { 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 }; //明文（IP)置换 const int datainitperm_table[64] = { 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 }; //数据扩展32-->48位 const int dataexpperm_table[48] = { 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 }; //S盒子，含有8个 4X16矩阵 用于数据替换 const int datasbox_table[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 }, } }; //数据换位 对S盒子转换过来的32进行换位 const int datapperm_table[32] = { 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 }; //(ip-1)置换，最终得到密文 const int datafp_table[64] = { 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 }; //模板函数 循环左移 template < size_t _NB > void rotateleft_bitset(bitset< _NB >& input, size_t step) { bitset< _NB > tmp = input; input <<= step; tmp >>= _NB - step; input |= tmp; } //模板函数 循环右移 template < size_t _NB > void rotateright_bitset(bitset< _NB >& input, size_t step) { bitset< _NB > tmp = input; input >>= step; tmp <<= _NB - step; input |= tmp; } //DES置 template < class Input, class Output, class Table> void Des_Permutation(const Input& input, Output& output, const Table& table, size_t TableSize) { for (size_t i = 0; i < TableSize; ++i) { output[i] = input[table[i] - 1]; } } //密钥置换 64->56去掉奇偶校验 void Des_Key_Permutation1(const _b64& input, _b56& output) { Des_Permutation(input, output, keyperm_table56, sizeof(keyperm_table56) / sizeof(int)); } //密钥压缩 56-->48 void Des_Key_CompPerm(const _b56& input, _b48& output) { Des_Permutation(input, output, keycompperm_table, sizeof(keycompperm_table) / sizeof(int)); } //密钥移动 56位分成两部分，左28 右28，分别移动 void Des_Key_Shift(_b56& key56, size_t step) { _b28 l28, r28; int i; for (i = 0; i < 28; ++i) { r28[i] = key56[i];//前28个分配给l28 l28[i] = key56[28 + i];//后28个分配给r28 } rotateleft_bitset(l28, step); rotateleft_bitset(r28, step); //左右28个合并成一个56 for (i = 0; i < 28; ++i) { key56[i] = r28[i]; key56[28 + i] = l28[i]; } } //产生子密钥 输入密钥产生子密钥 void Des_Key_Generate(const _b64& key, _vb48& subkey) { _b56 tmp56; Des_Key_Permutation1(key, tmp56);//64位密钥去掉奇偶位转变成56位 //16次迭代 for (int i = 0; i < 16; ++i) { _b48 tmp48; //按表左移 第i次左移 Des_Key_Shift(tmp56, keyshift_table[i]); //密钥压缩 56-->48位 Des_Key_CompPerm(tmp56, tmp48); //输出子密钥 // cout << "第"<<i+1<<"个子密钥: " << tmp48 << endl; //存储子密钥 subkey.push_back(tmp48); } } //字符型转换成二进制 获得字符的7位ASCII码 void Des_Char_To_Binary(char c, string& binary) { unsigned char tmp = c; binary.append((tmp & 0x80) ? "1" : "0"); binary.append((tmp & 0x40) ? "1" : "0"); binary.append((tmp & 0x20) ? "1" : "0"); binary.append((tmp & 0x10) ? "1" : "0"); binary.append((tmp & 0x08) ? "1" : "0"); binary.append((tmp & 0x04) ? "1" : "0"); binary.append((tmp & 0x02) ? "1" : "0"); binary.append((tmp & 0x01) ? "1" : "0"); } //字符串转成二进制 void Des_String_To_Binary(const string& input, _b64& output) { string binary; for (size_t i = 0; i < input.length(); ++i) { Des_Char_To_Binary(input[i], binary); } _b64 tmp64(binary);//声明时进行初始化 output = tmp64; } //生成密钥 void Des_String_To_Key(const string& key, _vb48& subkey) { _b64 tmp64; Des_String_To_Binary(key, tmp64); //生成64位密钥 Des_Key_Generate(tmp64, subkey); //64->56->移位进行16次迭代 } //置换后的明文，右侧32扩展成48位 void Des_Data_ExpPerm(const _b32& input, _b48& output) { //应用扩展矩阵 Des_Permutation(input, output, dataexpperm_table, sizeof(dataexpperm_table) / sizeof(int)); } //明文IP置换 void Des_Data_IP(const _b64& input, _b64& output) { Des_Permutation(input, output, datainitperm_table, sizeof(datainitperm_table) / sizeof(int)); } //明文和子密钥异或运算后 6转换成4位 void Des_Data_S(const _b6& input, _b4& output, int step) { bitset< 2 > tmp2; _b4 tmp4; tmp2[0] = input[5]; tmp2[1] = input