AES算法源码

aes.h

#include <windows.h>#include <stdio.h>/*    Nr 与 Nb, Nk 的关系(单位：DWORD)-----------------------------------------------------------------Nr             Nk=4        Nk=6        Nk=8-----------------------------------------------------------------Nb=4           10          12          14Nb=6           12          12          14Nb=8           14          14          14-----------------------------------------------------------------*/#define Nb         4    // AES 分组长度(单位：DWORD)#define MaxNk      8    // 最大密钥长度(单位：DWORD)#define MaxNr     14    // 最大加密轮数int Nk=4;     // AES-128 密钥长度(单位：DWORD)int Nr=10;    // AES-128 加密轮数/* LogTable 和 ExpTable 用来实现GF(2^8)上的乘法  */const BYTE LogTable[256]={0,0,25,1,50,2,26,198,75,199,27,104,51,238,223,3,100,4,224,14,52,141,129,239,76,113,8,200,248,105,28,193,125,194,29,181,249,185,39,106,77,228,166,114,154,201,9,120,101,47,138,5,33,15,225,36,18,240,130,69,53,147,218,142,150,143,219,189,54,208,206,148,19,92,210,241,64,70,131,56,102,221,253,48,191,6,139,98,179,37,226,152,34,136,145,16,126,110,72,195,163,182,30,66,58,107,40,84,250,133,61,186,43,121,10,21,155,159,94,202,78,212,172,229,243,115,167,87,175,88,168,80,244,234,214,116,79,174,233,213,231,230,173,232,44,215,117,122,235,22,11,245,89,203,95,176,156,169,81,160,127,12,246,111,23,196,73,236,216,67,31,45,164,118,123,183,204,187,62,90,251,96,177,134,59,82,161,108,170,85,41,157,151,178,135,144,97,190,220,252,188,149,207,205,55,63,91,209,83,57,132,60,65,162,109,71,20,42,158,93,86,242,211,171,68,17,146,217,35,32,46,137,180,124,184,38,119,153,227,165,103,74,237,222,197,49,254,24,13,99,140,128,192,247,112,7};const BYTE ExpTable[256]={1,3,5,15,17,51,85,255,26,46,114,150,161,248,19,53,95,225,56,72,216,115,149,164,247,2,6,10,30,34,102,170,229,52,92,228,55,89,235,38,106,190,217,112,144,171,230,49,83,245,4,12,20,60,68,204,79,209,104,184,211,110,178,205,76,212,103,169,224,59,77,215,98,166,241,8,24,40,120,136,131,158,185,208,107,189,220,127,129,152,179,206,73,219,118,154,181,196,87,249,16,48,80,240,11,29,39,105,187,214,97,163,254,25,43,125,135,146,173,236,47,113,147,174,233,32,96,160,251,22,58,78,210,109,183,194,93,231,50,86,250,21,63,65,195,94,226,61,71,201,64,192,91,237,44,116,156,191,218,117,159,186,213,100,172,239,42,126,130,157,188,223,122,142,137,128,155,182,193,88,232,35,101,175,234,37,111,177,200,67,197,84,252,31,33,99,165,244,7,9,27,45,119,153,176,203,70,202,69,207,74,222,121,139,134,145,168,227,62,66,198,81,243,14,18,54,90,238,41,123,141,140,143,138,133,148,167,242,13,23,57,75,221,124,132,151,162,253,28,36,108,180,199,82,246,1};/*  S盒 和 逆S盒 */const BYTE S_Box[256]={99,124,119,123,242,107,111,197,48,1,103,43,254,215,171,118,202,130,201,125,250,89,71,240,173,212,162,175,156,164,114,192,183,253,147,38,54,63,247,204,52,165,229,241,113,216,49,21,4,199,35,195,24,150,5,154,7,18,128,226,235,39,178,117,9,131,44,26,27,110,90,160,82,59,214,179,41,227,47,132,83,209,0,237,32,252,177,91,106,203,190,57,74,76,88,207,208,239,170,251,67,77,51,133,69,249,2,127,80,60,159,168,81,163,64,143,146,157,56,245,188,182,218,33,16,255,243,210,205,12,19,236,95,151,68,23,196,167,126,61,100,93,25,115,96,129,79,220,34,42,144,136,70,238,184,20,222,94,11,219,224,50,58,10,73,6,36,92,194,211,172,98,145,149,228,121,231,200,55,109,141,213,78,169,108,86,244,234,101,122,174,8,186,120,37,46,28,166,180,198,232,221,116,31,75,189,139,138,112,62,181,102,72,3,246,14,97,53,87,185,134,193,29,158,225,248,152,17,105,217,142,148,155,30,135,233,206,85,40,223,140,161,137,13,191,230,66,104,65,153,45,15,176,84,187,22};const BYTE Inv_S_Box[256]={82,9,106,213,48,54,165,56,191,64,163,158,129,243,215,251,124,227,57,130,155,47,255,135,52,142,67,68,196,222,233,203,84,123,148,50,166,194,35,61,238,76,149,11,66,250,195,78,8,46,161,102,40,217,36,178,118,91,162,73,109,139,209,37,114,248,246,100,134,104,152,22,212,164,92,204,93,101,182,146,108,112,72,80,253,237,185,218,94,21,70,87,167,141,157,132,144,216,171,0,140,188,211,10,247,228,88,5,184,179,69,6,208,44,30,143,202,63,15,2,193,175,189,3,1,19,138,107,58,145,17,65,79,103,220,234,151,242,207,206,240,180,230,115,150,172,116,34,231,173,53,133,226,249,55,232,28,117,223,110,71,241,26,113,29,41,197,137,111,183,98,14,170,24,190,27,252,86,62,75,198,210,121,32,154,219,192,254,120,205,90,244,31,221,168,51,136,7,199,49,177,18,16,89,39,128,236,95,96,81,127,169,25,181,74,13,45,229,122,159,147,201,156,239,160,224,59,77,174,42,245,176,200,235,187,60,131,83,153,97,23,43,4,126,186,119,214,38,225,105,20,99,85,33,12,125};const DWORD Rcon[32]={0x00,0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1B,0x36,0x6C,0xD8,0xAB,0x4D,0x9A,0x2F,0x5E,0xBC,0x63,0xc6,0x97,0x35,0x6A,0xD4,0xB3,0x7D,0xFA,0xEF,0xC5};/*   GF(2^8)上的乘法   */BYTE FieldMult(BYTE a, BYTE b){if( a && b )return ExpTable[ (LogTable[a] + LogTable[b] ) % 255];elsereturn 0;}BYTE FieldMult_(BYTE a, BYTE b){DWORD i, r, c;r = 0;c = 1;for(i=0; i<8; i++){if(b & c)r ^= a << i;c <<= 1;}c = 0x4000;for(i=14; i>7; i--){if(r & c)r ^= 0x11b << (i-8);c >>= 1;}return (BYTE)r;}void AddRoundKey(DWORD * a, DWORD * b){int i;for(i=0; i<Nb; i++){a[i] ^= b[i];}}void SubBytes(BYTE * a, DWORD size){for(DWORD i=0; i<size; i++){a[i] = S_Box[ a[i] ];}}void InvSubBytes(BYTE * a, DWORD size){for(DWORD i=0; i<size; i++){a[i] = Inv_S_Box[ a[i] ];}}void ShiftRows(BYTE a[4*Nb]){BYTE tmp;tmp = a[1];a[1] = a[5];a[5] = a[9];a[9] = a[13];a[13] = tmp;tmp = a[2];a[2] = a[10];a[10] = tmp;tmp = a[6];a[6] = a[14];a[14] = tmp;tmp = a[3];a[3] = a[15];a[15] = a[11];a[11] = a[7];a[7] = tmp;}void InvShiftRows(BYTE a[4*Nb]){BYTE tmp;tmp = a[1];a[1] = a[13];a[13] = a[9];a[9] = a[5];a[5] = tmp;tmp = a[2];a[2] = a[10];a[10] = tmp;tmp = a[6];a[6] = a[14];a[14] = tmp;tmp = a[3];a[3] = a[7];a[7] = a[11];a[11] = a[15];a[15] = tmp;}void MixColumns(BYTE a[4*Nb]){BYTE b[4];int i,j;for(j=0; j<Nb; j++){for(i=0; i<4; i++)b[i] = FieldMult(2, a[i+j*4]) ^ FieldMult(3, a[(i+1)%4+j*4]) ^ a[(i+2)%4+j*4] ^ a[(i+3)%4+j*4];for(i=0; i<4; i++)a[i+j*4] = b[i];}}void InvMixColumns(BYTE a[4*Nb]){BYTE b[4];int i,j;for(j=0; j<Nb; j++){for(i=0; i<4; i++)b[i] = FieldMult(0xE, a[i+j*4]) ^ FieldMult(0xB, a[(i+1)%4+j*4]) ^ FieldMult(0xD,a[(i+2)%4+j*4]) ^ FieldMult(0x9, a[(i+3)%4+j*4]);for(i=0; i<4; i++)a[i+j*4] = b[i];}}DWORD RotByte(DWORD  a){return ( a>>8 ) | (a << 24) ;}void KeyExpansion(BYTE key[4*MaxNk], DWORD dw[Nb*(MaxNr+1)]){int i;DWORD temp, temp2;for(i=0; i<Nk; i++){dw[i] = ( (DWORD)key[4*i] |( (DWORD)key[4*i+1] << 8 ) |( (DWORD)key[4*i+2] << 16 ) |( (DWORD)key[4*i+3] << 24 ) );}for(i=Nk; i<Nb*(Nr+1); i++){temp=dw[i-1];if( !( i % Nk ) ){temp2 = RotByte(temp);SubBytes((BYTE *)&temp2, 4);temp =  temp2 ^ Rcon[i/Nk];}else if( ( Nk > 6 ) && ( i % Nk == 4 ) ){SubBytes((BYTE *)&temp, 4);}dw[i] = dw[i-Nk] ^ temp;}}void AesEncrypt(BYTE in[4*Nb], BYTE out[4*Nb], DWORD dw[Nb*(MaxNr+1)]){BYTE state[4*Nb];memcpy(state, in, 4*Nb);int round;AddRoundKey((DWORD *)state, dw+0);for (round=1; round<Nr; round++){SubBytes(state, 4*Nb);ShiftRows(state);MixColumns(state);AddRoundKey((DWORD *)state, dw+round*Nb);}SubBytes(state, 4*Nb);ShiftRows(state);AddRoundKey((DWORD *)state, dw+Nr*Nb);memcpy(out, state, 4*Nb);}void AesDecrypt(BYTE in[4*Nb], BYTE out[4*Nb], DWORD dw[Nb*(MaxNr+1)]){BYTE state[4*Nb];memcpy(state, in, 4*Nb);int round;AddRoundKey((DWORD *)state, dw+Nr*Nb);InvShiftRows(state);InvSubBytes(state, 4*Nb);for(round=Nr-1; round>0; round--){AddRoundKey((DWORD *)state, dw+round*Nb);InvMixColumns(state);InvShiftRows(state);InvSubBytes(state, 4*Nb);}AddRoundKey((DWORD *)state, dw+0);memcpy(out, state, 4*Nb);}/*  设置密钥的长度 */void SetKey(int size){switch(size){case 128:Nk = 4;Nr = 10;break;case 192:Nk = 6;Nr = 12;break;case 256:Nk = 8;Nr = 14;break;default:break;}}

aes.cpp

#include "aes.h"/*   测试用的函数  */void Print(BYTE a[]){for(int i=0; i<4*Nb; i++){printf("%02X ", a[i]);}printf("\n\n");}void PrintKey(BYTE a[]){for(int i=0; i<4*Nk; i++){printf("%02X ", a[i]);if(i==15)printf("\n");}printf("\n\n");}int main(){SetKey(192);DWORD e_key[Nb*(MaxNr+1)];BYTE msg[4*Nb]={0x00, 0x11, 0x22, 0x33,0x44, 0x55, 0x66, 0x77,0x88, 0x99, 0xaa, 0xbb,0xcc, 0xdd, 0xee, 0xff};BYTE key[4*MaxNk]={0x00, 0x01, 0x02, 0x03,0x04, 0x05, 0x06, 0x07,0x08, 0x09, 0x0a, 0x0b,0x0c, 0x0d, 0x0e, 0x0f,0x10, 0x11, 0x12, 0x13,0x14, 0x15, 0x16, 0x17};BYTE encrypted_msg[4*Nb];BYTE decrypted_msg[4*Nb];printf("original message :\n");Print(msg);printf("key:\n");PrintKey(key);KeyExpansion(key, e_key);// 加密AesEncrypt(msg, encrypted_msg, e_key);printf("encrypted message:\n");Print(encrypted_msg);// 解密AesDecrypt(encrypted_msg, decrypted_msg, e_key);printf("decrypted message:\n");Print(decrypted_msg);printf("\n");// 使用文件测试printf("文件测试开始\n\n");SetKey(128);FILE * fp_msg, * fp_key, * fp_encrypted_msg;if(!(fp_msg=fopen("msg.txt", "rb"))){printf("error !!!! can not open file msg.txt !!\n\n");exit(0);}if(fread(msg, 1, 16, fp_msg)!=16){printf("error !!! msg less than  16 bit !!!\n\n");exit(0);}printf("original message :\n");Print(msg);fclose(fp_msg);if(!(fp_key=fopen("key.txt", "rb"))){printf("error !!!! can not open file key.txt !!\n\n");exit(0);}if(fread(key, 1, Nk*4, fp_key)!=(unsigned long)Nk*4){printf("error !!! key length error !!!\n\n");exit(0);}printf("key :\n");PrintKey(key);fclose(fp_key);KeyExpansion(key, e_key);// 加密AesEncrypt(msg, encrypted_msg, e_key);printf("encrypted message:\n");Print(encrypted_msg);if(!(fp_encrypted_msg=fopen("msg.cryp", "wb"))){printf("error !!!! can not build file msg.cryp !!\n\n");exit(0);}fwrite(encrypted_msg, 1, 16, fp_encrypted_msg);fclose(fp_encrypted_msg);// 解密AesDecrypt(encrypted_msg, decrypted_msg, e_key);printf("decrypted message:\n");Print(decrypted_msg);printf("\n");/*BYTE a=0x3;for(int i=0; i<255; i++){printf("3^%2d = %3d\n", i+2, a=FieldMult_(a, 0x3));}*/return 0;}