aes.cpp

單輸入系統模糊溫度控制器的實作.c語言程式

	KeyExpansion(CipherKey,ExKey);

	//Initial Round
	for (i=0;i<Nb*4;i++)
		*(buffer+i) ^= *(ExKey+i);
	//Rounds
	for (i=1;i<Nr;i++)
		Round(ExKey+4*Nb*i);

	//Final Round
	FinalRound(ExKey+4*Nb*Nr);

	return 0;
}

int AES::Decrypt(unsigned char* State, int bSize, unsigned char* CipherKey, int kSize)
{
	int i = 0;
	if (State == NULL || CipherKey == NULL)
		return 1;
	if (bSize != 128 && bSize != 192 && bSize != 256)
		return 2;
	if (kSize != 128 && kSize != 192 && kSize != 256)
		return 3;
	buffer = State;
	Nb = bSize / 32;
	Nk = kSize / 32;
	Nr = RoundT[3*(Nk/2-2)+(Nb/2-2)];

	if(ExKey != NULL)
	{
		delete ExKey;
		ExKey = NULL;
	}
	ExKey = new unsigned char[4*(Nb*(Nr+1))];
	I_KeyExpansion(CipherKey,ExKey);

	//Add Round Key
	for (i=0;i<Nb*4;i++)
		*(buffer+i) ^= *(ExKey+4*Nb*Nr+i);
	//Rounds
	for (i=Nr-1;i>0;i--)
		I_Round(ExKey+4*Nb*i);

	//Final Round
	I_FinalRound(ExKey);

	return 0;
}


int AES::KeyExpansion(unsigned char* Key, unsigned char*& EKey)
{
	int i= 0;
	unsigned char* pt=EKey;
	unsigned char* pt2 = NULL;
	unsigned char temp[4];
	if(Key==NULL || EKey==NULL)
		return 1;

	for (i=0;i<Nk;i++)
	{
		*pt = *(Key+(4*i));
		*(pt+1) = *(Key+(4*i+1));
		*(pt+2) = *(Key+(4*i+2));
		*(pt+3) = *(Key+(4*i+3));
		pt += 4;
	}//end for(i)

	for (i=Nk;i<Nb*(Nr+1);i++)
	{
		pt2 = pt - 4;
		memcpy(temp,pt2,4);
		if (i % Nk == 0)
		{
			unsigned char t;
			t = temp[0];
			temp[0] = temp[1];
			temp[1] = temp[2];
			temp[2] = temp[3];
			temp[3] = t;
			
			temp[0] = SBoxT[temp[0]];
			temp[1] = SBoxT[temp[1]];
			temp[2] = SBoxT[temp[2]];
			temp[3] = SBoxT[temp[3]];

			temp[0] ^= RconT[i/Nk];
			temp[1] ^= 0;
			temp[2] ^= 0;
			temp[3] ^= 0;
		}//end if
		else if (Nk > 6 && i % Nk == 4) 
		{
			temp[0] = SBoxT[temp[0]];
			temp[1] = SBoxT[temp[1]];
			temp[2] = SBoxT[temp[2]];
			temp[3] = SBoxT[temp[3]];
		}//end else if

		pt2 = pt - 4*Nk;
		*pt = *(pt2) ^ temp[0];
		*(pt+1) = *(pt2+1) ^ temp[1];
		*(pt+2) = *(pt2+2) ^ temp[2];
		*(pt+3) = *(pt2+3) ^ temp[3];
		pt += 4;
	}//end for(i)

	return 0;
}

int AES::I_KeyExpansion(unsigned char* Key, unsigned char*& EKey)
{
	int i= 0;
	unsigned char* temp;
	if(Key==NULL || EKey==NULL)
		return 1;
	KeyExpansion(Key,EKey);
	for (i=1;i<Nr;i++)
	{
		temp = EKey+4*Nb*i;
		InvMixColumn((temp));
	}

	return 0;
}



void AES::ShiftRow()
{
	unsigned char c1,c2,c3,t1[4],t2[4],t3[4],i;
	c1 = ShiftT[3*(Nb/2-2)];
	c2 = ShiftT[3*(Nb/2-2)+1];
	c3 = ShiftT[3*(Nb/2-2)+2];

	for (i=0;i<4;i++)
	{
		t1[i] = *(buffer+(4*i)+1);
		t2[i] = *(buffer+(4*i)+2);
		t3[i] = *(buffer+(4*i)+3);
	}

	for(i=0;i<Nb;i++)
	{
		*(buffer+4*i+1) = *(buffer+4*((i+c1)%Nb)+1);
		*(buffer+4*i+2) = *(buffer+4*((i+c2)%Nb)+2);
		*(buffer+4*i+3) = *(buffer+4*((i+c3)%Nb)+3);
	}

	for(i=c1;i>=1;i--)
		*(buffer+4*(Nb-i)+1) = t1[c1-i];
	for(i=c2;i>=1;i--)
		*(buffer+4*(Nb-i)+2) = t2[c2-i];
	for(i=c3;i>=1;i--)
		*(buffer+4*(Nb-i)+3) = t3[c3-i];
}