#define ENCRYPT 1 #define DECRYPT 0
static void printHex( char *cmd, int len );
static void printArray( const char *In, int len );
static void F_func(bool In[32], const bool Ki[48]); // f函数 static void S_func(bool Out[32], const bool In[48]); // S盒代替
static void Transform(bool *Out, bool *In, const char *Table, int len); // 变换 static void Xor(bool *InA, const bool *InB, int len); // 异或 static void RotateL(bool *In, int len, int loop); // 循环左移
static void ByteToBit(bool *Out, const char *In, int bits); // 字节组转换成位组 static void BitToByte(char *Out, const bool *In, int bits); // 位组转换成字节组
// 16位子密钥
static bool SubKey[16][48];
// 64位经过PC1转换为56位 (PC-1) const static char PC1_Table[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 };
// 左移
const static char LOOP_Table[16] = {
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 };
// 排列选择 2 (PC-2)
const static char PC2_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 };
// Ri_1（32位）经过变换E后膨胀为48位 (E) void F_func static const char E_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 };
// 8个4比特合并为32比特的排列 P const static char P_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, };
// 经过S盒 S-boxes
const static char S_Box[8][4][16] = { {
// 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 } } };
// 初始排列 (IP)
const static char IP_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 };
// L16与R16合并后经过IP_1的最终排列 (IP**-1) const static char IPR_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 };
void Des_SetKey(const char Key[8]); //生成子密钥
void Des_Run(char Out[8], char In[8], bool Type); //DES算法
void main(int argc, char *argv[]) { char key[12]={1,2,3,4,5,6,7,8}; char str[12]=\"Hello\"; char str2[12];
//printArray( PC2_Table, sizeof(PC2_Table)/sizeof(PC2_Table[0]) ); printf(\"Before encrypting: \"); puts(str); Des_SetKey(key); memset(str2, 0, sizeof(str2)); Des_Run(str2, str, ENCRYPT); printf(\"After encrypting: \"); printHex( str2, 8 ); memset(str, 0, sizeof(str)); printf(\"After decrypting: \"); Des_Run(str, str2, DECRYPT); puts(str); }
void Des_SetKey(const char Key[8]) {
int i;
static bool K[64], *KL = &K[0], *KR = &K[28];
ByteToBit(K, Key, 64); //转换为二进制
Transform(K, K, PC1_Table, 56); //64比特的密钥K，经过PC-1后，生成56比特的串。
//生成16个子密钥 for(i=0; i<16; i++) {
//循环左移，合并
RotateL(KL, 28, LOOP_Table[i]); RotateL(KR, 28, LOOP_Table[i]);
Transform(SubKey[i], K, PC2_Table, 48); } }
void Des_Run(char Out[8], char In[8], bool Type) {
int i;
static bool M[64], tmp[32], *Li = &M[0], *Ri = &M[32];
//转换为64位的数据块 ByteToBit(M, In, 64);
//IP置换 （初始）
Transform(M, M, IP_Table, 64);
//该比特串被分为32位的L0和32位的R0两部分。
if( Type == ENCRYPT ) {
//16轮置换
for(i=0; i<16; i++) {
memcpy(tmp, Ri, 32);
// R[i] = L[i-1] xor f(R[i-1], K[i]) F_func(Ri, SubKey[i]);
// Exclusive-or the resulting value with L[i-1]. // R[I]=P XOR L[I-1]
Xor(Ri, Li, 32);//将所得结果与明文的左32位进行异或运算
// L[i] = R[i-1]
memcpy(Li, tmp, 32);//将明文的左右32位交换 } } else {
// 如果解密则反转子密钥顺序 for(i=15; i>=0; i--) {
memcpy(tmp, Li, 32); F_func(Li, SubKey[i]); Xor(Li, Ri, 32);
memcpy(Ri, tmp, 32); } }
//R16与L16合并成64位的比特串。R16一定要排在L16前面。R16与L16合并后成的比特串，经过置换IP-1后所得的比特串就是密文。 Transform(M, M, IPR_Table, 64);
BitToByte(Out, M, 64); }
//将32比特的输入再转化为32比特的输出 void F_func(bool In[32], const bool Ki[48]) {
static bool MR[48];
//输入Ri-1(32比特)经过变换E后，膨胀为48比特 Transform(MR, In, E_Table, 48);
//异或
Xor(MR, Ki, 48);
//膨胀后的比特串分为8组，每组6比特。各组经过各自的S盒后，又变为4比特(具体过程见后)，合并后又成为32比特。 S_func(In, MR);
//该32比特经过P变换后，输出的比特串才是32比特的f (Ri-1,Ki)。 Transform(In, In, P_Table, 32); }
void S_func(bool Out[32], const bool In[48]) {
char j,m,n;
//膨胀后的比特串分为8组，每组6比特。 for(j=0; j<8; j++,In+=6,Out+=4) {
//在其输入In[0],In[1],In[2],In[3],In[4],In[5]中，计算出m=In[0]*2+In[5], n=In[4]+In[3]*2+In[2]*4+In[1]*8，再从Sj表中查出m行，n列的值Smn。将Smn化为二进制，即得Si盒的输出。
m = (In[0]<<1) + In[5];
n = (In[1]<<3) + (In[2]<<2) + (In[3]<<1) + In[4];
ByteToBit(Out, &S_Box[(int)j][(int)m][(int)n], 4); } }
// 打印指定位置指定长度HEX值 static void printHex( char *cmd, int len ) { int i;
for(i=0; i printf(\"\\n\"); } // 打印数组测试用 static void printArray( const char *In, int len ) { int i; char tmp[256]; memset(tmp, 0, sizeof(tmp)); for( i=0; i for( i=0; i printf(\"\\n\"); } void Transform(bool *Out, bool *In, const char *Table, int len) { int i; static bool tmp[256]; for(i=0; i memcpy(Out, tmp, len); } void Xor(bool *InA, const bool *InB, int len) { int i; for(i=0; i InA[i] ^= InB[i]; } } void RotateL(bool *In, int len, int loop) { static bool tmp[256]; // Sample: loop=2 memcpy(tmp, In, loop); // In=12345678 tmp=12 memcpy(In, In+loop, len-loop); // In=345678 memcpy(In+len-loop, tmp, loop); // In=34567812 } // Sample: // In = [0x01] // Out = [0x01] [0x00] [0x00] [0x00] [0x00] [0x00] [0x00] [0x00] void ByteToBit(bool *Out, const char *In, int bits) { int i; for(i=0; i void BitToByte(char *Out, const bool *In, int bits) { int i; memset(Out, 0, (bits+7)/8); for(i=0; i 因篇幅问题不能全部显示，请点此查看更多更全内容