void MixColumns(BYTE State[4][4])
{
BYTE temp[4*4];
DWORD i,j;
for(j=0;j<4;j++) //2 3 1 1 Page107
{ //1 2 3 1
for(i=0;i<4;i++) //1 1 2 3
{ //3 1 1 2
temp[4*i+j]=State[i][j];
}
}
for(j=0;j<4;j++)
{
State[0][j] = (BYTE) ( (DWORD)gfmultby02(temp[0+j]) ^ (DWORD)gfmultby03(temp[4*1+j]) ^
(DWORD)gfmultby01(temp[4*2+j]) ^ (DWORD)gfmultby01(temp[4*3+j]) );
State[1][j] = (BYTE) ( (DWORD)gfmultby01(temp[0+j]) ^ (DWORD)gfmultby02(temp[4*1+j]) ^
(DWORD)gfmultby03(temp[4*2+j]) ^ (DWORD)gfmultby01(temp[4*3+j]) );
State[2][j] = (BYTE) ( (DWORD)gfmultby01(temp[0+j]) ^ (DWORD)gfmultby01(temp[4*1+j]) ^
(DWORD)gfmultby02(temp[4*2+j]) ^ (DWORD)gfmultby03(temp[4*3+j]) );
State[3][j] = (BYTE) ( (DWORD)gfmultby03(temp[0+j]) ^ (DWORD)gfmultby01(temp[4*1+j]) ^
(DWORD)gfmultby01(temp[4*2+j]) ^ (DWORD)gfmultby02(temp[4*3+j]) );
}
}
void MixColumns(ctx_aes* aes)
{
unsigned char temp[4*4];
int r,c;
for (r = 0; r < 4; r++) // copy State into temp[]
{
for (c = 0; c < 4; c++)
{
temp[4*r+c] = aes->State[r][c];
}
}
for (c = 0; c < 4; c++)
{
aes->State[0][c] = (unsigned char) ( (int)gfmultby02(temp[0+c]) ^ (int)gfmultby03(temp[4*1+c]) ^
(int)gfmultby01(temp[4*2+c]) ^ (int)gfmultby01(temp[4*3+c]) );
aes->State[1][c] = (unsigned char) ( (int)gfmultby01(temp[0+c]) ^ (int)gfmultby02(temp[4*1+c]) ^
(int)gfmultby03(temp[4*2+c]) ^ (int)gfmultby01(temp[4*3+c]) );
aes->State[2][c] = (unsigned char) ( (int)gfmultby01(temp[0+c]) ^ (int)gfmultby01(temp[4*1+c]) ^
(int)gfmultby02(temp[4*2+c]) ^ (int)gfmultby03(temp[4*3+c]) );
aes->State[3][c] = (unsigned char) ( (int)gfmultby03(temp[0+c]) ^ (int)gfmultby01(temp[4*1+c]) ^
(int)gfmultby01(temp[4*2+c]) ^ (int)gfmultby02(temp[4*3+c]) );
}
} // MixColumns
