AES算法的c++实现
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1、AES.h
#include<cstdio> #include<cstring> #include<algorithm> #include<cstdlib> #include<iostream> #include<cmath> class AES{ public: AES(unsigned char* key); virtual ~AES(); unsigned char* Cipher(unsigned char* input);//16字节为一组 unsigned char* InvCipher(unsigned char* input); void* Cipher(void* input, int length=0);//初始化过了 void* InvCipher(void* input, int length); private: unsigned char Sbox[256]; unsigned char InvSbox[256];//1字节=8位 unsigned char w[11][4][4]; void KeyExpansion(unsigned char* key, unsigned char w[][4][4]); unsigned char FFmul(unsigned char a, unsigned char b); void SubBytes(unsigned char state[][4]); void ShiftRows(unsigned char state[][4]); void MixColumns(unsigned char state[][4]); void AddRoundKey(unsigned char state[][4], unsigned char k[][4]); void InvSubBytes(unsigned char state[][4]); void InvShiftRows(unsigned char state[][4]); void InvMixColumns(unsigned char state[][4]); };
2、AES.cpp
#include "string.h" #include "AES.h" //unsigned char 8位 1字节 AES::AES(unsigned char* key){ unsigned char sBox[] ={ 0x63,0x7c,0x77,0x7b,0xf2,0x6b,0x6f,0xc5,0x30,0x01,0x67,0x2b,0xfe,0xd7,0xab,0x76, 0xca,0x82,0xc9,0x7d,0xfa,0x59,0x47,0xf0,0xad,0xd4,0xa2,0xaf,0x9c,0xa4,0x72,0xc0, 0xb7,0xfd,0x93,0x26,0x36,0x3f,0xf7,0xcc,0x34,0xa5,0xe5,0xf1,0x71,0xd8,0x31,0x15, 0x04,0xc7,0x23,0xc3,0x18,0x96,0x05,0x9a,0x07,0x12,0x80,0xe2,0xeb,0x27,0xb2,0x75, 0x09,0x83,0x2c,0x1a,0x1b,0x6e,0x5a,0xa0,0x52,0x3b,0xd6,0xb3,0x29,0xe3,0x2f,0x84, 0x53,0xd1,0x00,0xed,0x20,0xfc,0xb1,0x5b,0x6a,0xcb,0xbe,0x39,0x4a,0x4c,0x58,0xcf, 0xd0,0xef,0xaa,0xfb,0x43,0x4d,0x33,0x85,0x45,0xf9,0x02,0x7f,0x50,0x3c,0x9f,0xa8, 0x51,0xa3,0x40,0x8f,0x92,0x9d,0x38,0xf5,0xbc,0xb6,0xda,0x21,0x10,0xff,0xf3,0xd2, 0xcd,0x0c,0x13,0xec,0x5f,0x97,0x44,0x17,0xc4,0xa7,0x7e,0x3d,0x64,0x5d,0x19,0x73, 0x60,0x81,0x4f,0xdc,0x22,0x2a,0x90,0x88,0x46,0xee,0xb8,0x14,0xde,0x5e,0x0b,0xdb, 0xe0,0x32,0x3a,0x0a,0x49,0x06,0x24,0x5c,0xc2,0xd3,0xac,0x62,0x91,0x95,0xe4,0x79, 0xe7,0xc8,0x37,0x6d,0x8d,0xd5,0x4e,0xa9,0x6c,0x56,0xf4,0xea,0x65,0x7a,0xae,0x08, 0xba,0x78,0x25,0x2e,0x1c,0xa6,0xb4,0xc6,0xe8,0xdd,0x74,0x1f,0x4b,0xbd,0x8b,0x8a, 0x70,0x3e,0xb5,0x66,0x48,0x03,0xf6,0x0e,0x61,0x35,0x57,0xb9,0x86,0xc1,0x1d,0x9e, 0xe1,0xf8,0x98,0x11,0x69,0xd9,0x8e,0x94,0x9b,0x1e,0x87,0xe9,0xce,0x55,0x28,0xdf, 0x8c,0xa1,0x89,0x0d,0xbf,0xe6,0x42,0x68,0x41,0x99,0x2d,0x0f,0xb0,0x54,0xbb,0x16 }; unsigned char invsBox[256] = { 0x52,0x09,0x6a,0xd5,0x30,0x36,0xa5,0x38,0xbf,0x40,0xa3,0x9e,0x81,0xf3,0xd7,0xfb, 0x7c,0xe3,0x39,0x82,0x9b,0x2f,0xff,0x87,0x34,0x8e,0x43,0x44,0xc4,0xde,0xe9,0xcb, 0x54,0x7b,0x94,0x32,0xa6,0xc2,0x23,0x3d,0xee,0x4c,0x95,0x0b,0x42,0xfa,0xc3,0x4e, 0x08,0x2e,0xa1,0x66,0x28,0xd9,0x24,0xb2,0x76,0x5b,0xa2,0x49,0x6d,0x8b,0xd1,0x25, 0x72,0xf8,0xf6,0x64,0x86,0x68,0x98,0x16,0xd4,0xa4,0x5c,0xcc,0x5d,0x65,0xb6,0x92, 0x6c,0x70,0x48,0x50,0xfd,0xed,0xb9,0xda,0x5e,0x15,0x46,0x57,0xa7,0x8d,0x9d,0x84, 0x90,0xd8,0xab,0x00,0x8c,0xbc,0xd3,0x0a,0xf7,0xe4,0x58,0x05,0xb8,0xb3,0x45,0x06, 0xd0,0x2c,0x1e,0x8f,0xca,0x3f,0x0f,0x02,0xc1,0xaf,0xbd,0x03,0x01,0x13,0x8a,0x6b, 0x3a,0x91,0x11,0x41,0x4f,0x67,0xdc,0xea,0x97,0xf2,0xcf,0xce,0xf0,0xb4,0xe6,0x73, 0x96,0xac,0x74,0x22,0xe7,0xad,0x35,0x85,0xe2,0xf9,0x37,0xe8,0x1c,0x75,0xdf,0x6e, 0x47,0xf1,0x1a,0x71,0x1d,0x29,0xc5,0x89,0x6f,0xb7,0x62,0x0e,0xaa,0x18,0xbe,0x1b, 0xfc,0x56,0x3e,0x4b,0xc6,0xd2,0x79,0x20,0x9a,0xdb,0xc0,0xfe,0x78,0xcd,0x5a,0xf4, 0x1f,0xdd,0xa8,0x33,0x88,0x07,0xc7,0x31,0xb1,0x12,0x10,0x59,0x27,0x80,0xec,0x5f, 0x60,0x51,0x7f,0xa9,0x19,0xb5,0x4a,0x0d,0x2d,0xe5,0x7a,0x9f,0x93,0xc9,0x9c,0xef, 0xa0,0xe0,0x3b,0x4d,0xae,0x2a,0xf5,0xb0,0xc8,0xeb,0xbb,0x3c,0x83,0x53,0x99,0x61, 0x17,0x2b,0x04,0x7e,0xba,0x77,0xd6,0x26,0xe1,0x69,0x14,0x63,0x55,0x21,0x0c,0x7d }; memcpy(Sbox, sBox, 256); memcpy(InvSbox, invsBox, 256); KeyExpansion(key, w); }//构造函数 AES::~AES(){}//析构函数 unsigned char* AES::Cipher(unsigned char* input){//只往后16个字节 unsigned char state[4][4]; int i,r,c; for(r=0; r<4; r++){ for(c=0; c<4 ;c++){ state[r][c] = input[c*4+r]; } } AddRoundKey(state,w[0]);//原秘钥，一共11轮密钥 for(i=1; i<=10; i++){ SubBytes(state); ShiftRows(state); if(i!=10)MixColumns(state); AddRoundKey(state,w[i]); } for(r=0; r<4; r++){ for(c=0; c<4 ;c++){ input[c*4+r] = state[r][c]; } } return input; } unsigned char* AES::InvCipher(unsigned char* input){ unsigned char state[4][4]; int i,r,c; for(r=0; r<4; r++){ for(c=0; c<4 ;c++){ state[r][c] = input[c*4+r]; } } AddRoundKey(state, w[10]);//注意逆向的顺序 for(i=9; i>=0; i--){ InvShiftRows(state); InvSubBytes(state); AddRoundKey(state, w[i]); if(i){ InvMixColumns(state); } } for(r=0; r<4; r++){ for(c=0; c<4 ;c++){ input[c*4+r] = state[r][c]; } } return input; } void* AES::Cipher(void* input, int length){ unsigned char* in = (unsigned char*) input; int i; if(!length){ while(*(in+length++)); in = (unsigned char*) input; } for(i=0; i<length; i+=16){ Cipher(in+i); } return input; } void* AES::InvCipher(void* input, int length){ unsigned char* in = (unsigned char*) input; int i; for(i=0; i<length; i+=16){ InvCipher(in+i); } return input; } void AES::KeyExpansion(unsigned char* key, unsigned char w[][4][4]){ int i,j,r,c; unsigned char rc[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36};//轮常量 for(r=0; r<4; r++){ for(c=0; c<4; c++){ w[0][r][c] = key[r+c*4]; } } for(i=1; i<=10; i++){ for(j=0; j<4; j++){ unsigned char t[4]; for(r=0; r<4; r++){ t[r] = j ? w[i][r][j-1] : w[i-1][r][3]; } if(j == 0){ for(r=0; r<=3; r++){ t[r] = Sbox[t[(r+1)%4]]; } t[0] ^= rc[i-1]; } for(r=0; r<4; r++){ w[i][r][j] = w[i-1][r][j] ^ t[r]; } } } } //有限域乘法 unsigned char AES::FFmul(unsigned char a, unsigned char b){ unsigned char bw[4]; unsigned char res=0; int i; bw[0] = b; for(i=1; i<4; i++){ bw[i] = bw[i-1]<<1; if(bw[i-1]&0x80){ bw[i]^=0x1b; } } for(i=0; i<4; i++){ if((a>>i)&0x01){ res ^= bw[i]; } } return res; } //字节替代 void AES::SubBytes(unsigned char state[][4]){ int r,c; for(r=0; r<4; r++){ for(c=0; c<4; c++){ state[r][c] = Sbox[state[r][c]]; } } } //行移位变换 void AES::ShiftRows(unsigned char state[][4]){ unsigned char t[4]; int r,c; for(r=1; r<4; r++){ for(c=0; c<4; c++){ t[c] = state[r][(c+r)%4]; } for(c=0; c<4; c++){ state[r][c] = t[c]; } } } //列混淆变换 void AES::MixColumns(unsigned char state[][4]){ unsigned char t[4]; int r,c; for(c=0; c< 4; c++){ for(r=0; r<4; r++){ t[r] = state[r][c]; } for(r=0; r<4; r++){ state[r][c] = FFmul(0x02, t[r]) ^ FFmul(0x03, t[(r+1)%4]) ^ FFmul(0x01, t[(r+2)%4]) ^ FFmul(0x01, t[(r+3)%4]); } } } //轮密钥加变换，正逆是一样的，异或 void AES::AddRoundKey(unsigned char state[][4], unsigned char k[][4]){ int r,c; for(c=0; c<4; c++){ for(r=0; r<4; r++){ state[r][c] ^= k[r][c]; } } } //逆字节替代 void AES::InvSubBytes(unsigned char state[][4]){ int r,c; for(r=0; r<4; r++){ for(c=0; c<4; c++){ state[r][c] = InvSbox[state[r][c]]; } } } //逆行移位变换 void AES::InvShiftRows(unsigned char state[][4]){ unsigned char t[4]; int r,c; for(r=1; r<4; r++){ for(c=0; c<4; c++){ t[c] = state[r][(c-r+4)%4]; } for(c=0; c<4; c++){ state[r][c] = t[c]; } } } //逆列混淆变换 void AES::InvMixColumns(unsigned char state[][4]){ unsigned char t[4]; int r,c; for(c=0; c< 4; c++){ for(r=0; r<4; r++){ t[r] = state[r][c]; } for(r=0; r<4; r++){ state[r][c] = FFmul(0x0e, t[r]) ^ FFmul(0x0b, t[(r+1)%4]) ^ FFmul(0x0d, t[(r+2)%4]) ^ FFmul(0x09, t[(r+3)%4]); } } }
3、main.cpp
#include "AES.h" void print(unsigned char* state); int main(int argc, char* argv[]){ unsigned char input[] ={ 0x32, 0x43, 0xf6, 0xa8, 0x88, 0x5a, 0x30, 0x8d, 0x31, 0x31, 0x98, 0xa2, 0xe0, 0x37, 0x07, 0x34 }; unsigned char key[]={ 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6, 0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c };//128位，16字节 AES aes(key); printf("Input:\n"); print(input); aes.Cipher(input); printf("After Cipher:\n"); print(input); aes.InvCipher(input); printf("After InvCipher:\n"); print(input); int j; printf("\n"); char str[32] = "Hello,My AES Cipher!"; for(j=0; j<32; j++)printf("%X ",(unsigned char)str[j]); printf("\n"); aes.Cipher((void *)str); for(j=0; j<32; j++)printf("%X ",(unsigned char)str[j]); printf("\n"); aes.InvCipher((void *)str,21); for(j=0; j<32; j++)printf("%X ",(unsigned char)str[j]); printf("\n"); return 0; } void print(unsigned char* state){ int i; /*for(i=0; i<16; i++){ printf("%s%X ",state[i]>15 ? "" : "0", state[i]); }*/ for(int i=0;i<16;i++) printf("%02x ",state[i]); printf("\n"); }
