// rijndael.cpp - modified by Chris Morgan <cmorgan@wpi.edu>
// and Wei Dai from Paulo Baretto's Rijndael implementation
// The original code and all modifications are in the public domain.

// This is the original introductory comment:

/**
 * version 3.0 (December 2000)
 *
 * Optimised ANSI C code for the Rijndael cipher (now AES)
 *
 * author Vincent Rijmen <vincent.rijmen@esat.kuleuven.ac.be>
 * author Antoon Bosselaers <antoon.bosselaers@esat.kuleuven.ac.be>
 * author Paulo Barreto <paulo.barreto@terra.com.br>
 *
 * This code is hereby placed in the public domain.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "pch.h"
#include "rijndael.h"
#include "misc.h"

NAMESPACE_BEGIN(CryptoPP)

void Rijndael::Base::UncheckedSetKey(CipherDir dir, const byte *userKey, unsigned int keylen)
{
	AssertValidKeyLength(keylen);

	m_rounds = keylen/4 + 6;
	m_key.New(4*(m_rounds+1));

	word32 temp, *rk = m_key;
	unsigned int i=0;

	GetUserKey(BIG_ENDIAN_ORDER, rk, keylen/4, userKey, keylen);

	switch(keylen)
	{
	case 16:
		while (true)
		{
			temp  = rk[3];
			rk[4] = rk[0] ^
				(Te4[GETBYTE(temp, 2)] & 0xff000000) ^
				(Te4[GETBYTE(temp, 1)] & 0x00ff0000) ^
				(Te4[GETBYTE(temp, 0)] & 0x0000ff00) ^
				(Te4[GETBYTE(temp, 3)] & 0x000000ff) ^
				rcon[i];
			rk[5] = rk[1] ^ rk[4];
			rk[6] = rk[2] ^ rk[5];
			rk[7] = rk[3] ^ rk[6];
			if (++i == 10)
				break;
			rk += 4;
		}
		break;

	case 24:
		while (true)	// for (;;) here triggers a bug in VC60 SP4 w/ Processor Pack
		{
			temp = rk[ 5];
			rk[ 6] = rk[ 0] ^
				(Te4[GETBYTE(temp, 2)] & 0xff000000) ^
				(Te4[GETBYTE(temp, 1)] & 0x00ff0000) ^
				(Te4[GETBYTE(temp, 0)] & 0x0000ff00) ^
				(Te4[GETBYTE(temp, 3)] & 0x000000ff) ^
				rcon[i];
			rk[ 7] = rk[ 1] ^ rk[ 6];
			rk[ 8] = rk[ 2] ^ rk[ 7];
			rk[ 9] = rk[ 3] ^ rk[ 8];
			if (++i == 8)
				break;
			rk[10] = rk[ 4] ^ rk[ 9];
			rk[11] = rk[ 5] ^ rk[10];
			rk += 6;
		}
		break;

	case 32:
        while (true)
		{
        	temp = rk[ 7];
        	rk[ 8] = rk[ 0] ^
        		(Te4[GETBYTE(temp, 2)] & 0xff000000) ^
        		(Te4[GETBYTE(temp, 1)] & 0x00ff0000) ^
        		(Te4[GETBYTE(temp, 0)] & 0x0000ff00) ^
        		(Te4[GETBYTE(temp, 3)] & 0x000000ff) ^
        		rcon[i];
        	rk[ 9] = rk[ 1] ^ rk[ 8];
        	rk[10] = rk[ 2] ^ rk[ 9];
        	rk[11] = rk[ 3] ^ rk[10];
			if (++i == 7)
				break;
        	temp = rk[11];
        	rk[12] = rk[ 4] ^
        		(Te4[GETBYTE(temp, 3)] & 0xff000000) ^
        		(Te4[GETBYTE(temp, 2)] & 0x00ff0000) ^
        		(Te4[GETBYTE(temp, 1)] & 0x0000ff00) ^
        		(Te4[GETBYTE(temp, 0)] & 0x000000ff);
        	rk[13] = rk[ 5] ^ rk[12];
        	rk[14] = rk[ 6] ^ rk[13];
        	rk[15] = rk[ 7] ^ rk[14];

			rk += 8;
        }
		break;
	}

	if (dir == DECRYPTION)
	{
		unsigned int i, j;
		rk = m_key;

		/* invert the order of the round keys: */
		for (i = 0, j = 4*m_rounds; i < j; i += 4, j -= 4) {
			temp = rk[i    ]; rk[i    ] = rk[j    ]; rk[j    ] = temp;
			temp = rk[i + 1]; rk[i + 1] = rk[j + 1]; rk[j + 1] = temp;
			temp = rk[i + 2]; rk[i + 2] = rk[j + 2]; rk[j + 2] = temp;
			temp = rk[i + 3]; rk[i + 3] = rk[j + 3]; rk[j + 3] = temp;
		}
		/* apply the inverse MixColumn transform to all round keys but the first and the last: */
		for (i = 1; i < m_rounds; i++) {
			rk += 4;
			rk[0] =
				Td0[Te4[GETBYTE(rk[0], 3)] & 0xff] ^
				Td1[Te4[GETBYTE(rk[0], 2)] & 0xff] ^
				Td2[Te4[GETBYTE(rk[0], 1)] & 0xff] ^
				Td3[Te4[GETBYTE(rk[0], 0)] & 0xff];
			rk[1] =
				Td0[Te4[GETBYTE(rk[1], 3)] & 0xff] ^
				Td1[Te4[GETBYTE(rk[1], 2)] & 0xff] ^
				Td2[Te4[GETBYTE(rk[1], 1)] & 0xff] ^
				Td3[Te4[GETBYTE(rk[1], 0)] & 0xff];
			rk[2] =
				Td0[Te4[GETBYTE(rk[2], 3)] & 0xff] ^
				Td1[Te4[GETBYTE(rk[2], 2)] & 0xff] ^
				Td2[Te4[GETBYTE(rk[2], 1)] & 0xff] ^
				Td3[Te4[GETBYTE(rk[2], 0)] & 0xff];
			rk[3] =
				Td0[Te4[GETBYTE(rk[3], 3)] & 0xff] ^
				Td1[Te4[GETBYTE(rk[3], 2)] & 0xff] ^
				Td2[Te4[GETBYTE(rk[3], 1)] & 0xff] ^
				Td3[Te4[GETBYTE(rk[3], 0)] & 0xff];
		}
	}
}

typedef BlockGetAndPut<word32, BigEndian> Block;

void Rijndael::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	word32 s0, s1, s2, s3, t0, t1, t2, t3;
	const word32 *rk = m_key;

    /*
	 * map byte array block to cipher state
	 * and add initial round key:
	 */
	Block::Get(inBlock)(s0)(s1)(s2)(s3);
	s0 ^= rk[0];
	s1 ^= rk[1];
	s2 ^= rk[2];
	s3 ^= rk[3];
    /*
	 * Nr - 1 full rounds:
	 */
    unsigned int r = m_rounds >> 1;
    for (;;) {
        t0 =
            Te0[GETBYTE(s0, 3)] ^
            Te1[GETBYTE(s1, 2)] ^
            Te2[GETBYTE(s2, 1)] ^
            Te3[GETBYTE(s3, 0)] ^
            rk[4];
        t1 =
            Te0[GETBYTE(s1, 3)] ^
            Te1[GETBYTE(s2, 2)] ^
            Te2[GETBYTE(s3, 1)] ^
            Te3[GETBYTE(s0, 0)] ^
            rk[5];
        t2 =
            Te0[GETBYTE(s2, 3)] ^
            Te1[GETBYTE(s3, 2)] ^
            Te2[GETBYTE(s0, 1)] ^
            Te3[GETBYTE(s1, 0)] ^
            rk[6];
        t3 =
            Te0[GETBYTE(s3, 3)] ^
            Te1[GETBYTE(s0, 2)] ^
            Te2[GETBYTE(s1, 1)] ^
            Te3[GETBYTE(s2, 0)] ^
            rk[7];

        rk += 8;
        if (--r == 0) {
            break;
        }

        s0 =
            Te0[GETBYTE(t0, 3)] ^
            Te1[GETBYTE(t1, 2)] ^
            Te2[GETBYTE(t2, 1)] ^
            Te3[GETBYTE(t3, 0)] ^
            rk[0];
        s1 =
            Te0[GETBYTE(t1, 3)] ^
            Te1[GETBYTE(t2, 2)] ^
            Te2[GETBYTE(t3, 1)] ^
            Te3[GETBYTE(t0, 0)] ^
            rk[1];
        s2 =
            Te0[GETBYTE(t2, 3)] ^
            Te1[GETBYTE(t3, 2)] ^
            Te2[GETBYTE(t0, 1)] ^
            Te3[GETBYTE(t1, 0)] ^
            rk[2];
        s3 =
            Te0[GETBYTE(t3, 3)] ^
            Te1[GETBYTE(t0, 2)] ^
            Te2[GETBYTE(t1, 1)] ^
            Te3[GETBYTE(t2, 0)] ^
            rk[3];
    }
    /*
	 * apply last round and
	 * map cipher state to byte array block:
	 */

	s0 =
		(Te4[GETBYTE(t0, 3)] & 0xff000000) ^
		(Te4[GETBYTE(t1, 2)] & 0x00ff0000) ^
		(Te4[GETBYTE(t2, 1)] & 0x0000ff00) ^
		(Te4[GETBYTE(t3, 0)] & 0x000000ff) ^
		rk[0];
	s1 =
		(Te4[GETBYTE(t1, 3)] & 0xff000000) ^
		(Te4[GETBYTE(t2, 2)] & 0x00ff0000) ^
		(Te4[GETBYTE(t3, 1)] & 0x0000ff00) ^
		(Te4[GETBYTE(t0, 0)] & 0x000000ff) ^
		rk[1];
	s2 =
		(Te4[GETBYTE(t2, 3)] & 0xff000000) ^
		(Te4[GETBYTE(t3, 2)] & 0x00ff0000) ^
		(Te4[GETBYTE(t0, 1)] & 0x0000ff00) ^
		(Te4[GETBYTE(t1, 0)] & 0x000000ff) ^
		rk[2];
	s3 =
		(Te4[GETBYTE(t3, 3)] & 0xff000000) ^
		(Te4[GETBYTE(t0, 2)] & 0x00ff0000) ^
		(Te4[GETBYTE(t1, 1)] & 0x0000ff00) ^
		(Te4[GETBYTE(t2, 0)] & 0x000000ff) ^
		rk[3];

	Block::Put(xorBlock, outBlock)(s0)(s1)(s2)(s3);
}

void Rijndael::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
{
	word32 s0, s1, s2, s3, t0, t1, t2, t3;
    const word32 *rk = m_key;

    /*
	 * map byte array block to cipher state
	 * and add initial round key:
	 */
	Block::Get(inBlock)(s0)(s1)(s2)(s3);
	s0 ^= rk[0];
	s1 ^= rk[1];
	s2 ^= rk[2];
	s3 ^= rk[3];
    /*
     * Nr - 1 full rounds:
     */
    unsigned int r = m_rounds >> 1;
    for (;;) {
        t0 =
            Td0[GETBYTE(s0, 3)] ^
            Td1[GETBYTE(s3, 2)] ^
            Td2[GETBYTE(s2, 1)] ^
            Td3[GETBYTE(s1, 0)] ^
            rk[4];
        t1 =
            Td0[GETBYTE(s1, 3)] ^
            Td1[GETBYTE(s0, 2)] ^
            Td2[GETBYTE(s3, 1)] ^
            Td3[GETBYTE(s2, 0)] ^
            rk[5];
        t2 =
            Td0[GETBYTE(s2, 3)] ^
            Td1[GETBYTE(s1, 2)] ^
            Td2[GETBYTE(s0, 1)] ^
            Td3[GETBYTE(s3, 0)] ^
            rk[6];
        t3 =
            Td0[GETBYTE(s3, 3)] ^
            Td1[GETBYTE(s2, 2)] ^
            Td2[GETBYTE(s1, 1)] ^
            Td3[GETBYTE(s0, 0)] ^
            rk[7];

        rk += 8;
        if (--r == 0) {
            break;
        }

        s0 =
            Td0[GETBYTE(t0, 3)] ^
            Td1[GETBYTE(t3, 2)] ^
            Td2[GETBYTE(t2, 1)] ^
            Td3[GETBYTE(t1, 0)] ^
            rk[0];
        s1 =
            Td0[GETBYTE(t1, 3)] ^
            Td1[GETBYTE(t0, 2)] ^
            Td2[GETBYTE(t3, 1)] ^
            Td3[GETBYTE(t2, 0)] ^
            rk[1];
        s2 =
            Td0[GETBYTE(t2, 3)] ^
            Td1[GETBYTE(t1, 2)] ^
            Td2[GETBYTE(t0, 1)] ^
            Td3[GETBYTE(t3, 0)] ^
            rk[2];
        s3 =
            Td0[GETBYTE(t3, 3)] ^
            Td1[GETBYTE(t2, 2)] ^
            Td2[GETBYTE(t1, 1)] ^
            Td3[GETBYTE(t0, 0)] ^
            rk[3];
    }
    /*
	 * apply last round and
	 * map cipher state to byte array block:
	 */
   	s0 =
   		(Td4[GETBYTE(t0, 3)] & 0xff000000) ^
   		(Td4[GETBYTE(t3, 2)] & 0x00ff0000) ^
   		(Td4[GETBYTE(t2, 1)] & 0x0000ff00) ^
   		(Td4[GETBYTE(t1, 0)] & 0x000000ff) ^
   		rk[0];
   	s1 =
   		(Td4[GETBYTE(t1, 3)] & 0xff000000) ^
   		(Td4[GETBYTE(t0, 2)] & 0x00ff0000) ^
   		(Td4[GETBYTE(t3, 1)] & 0x0000ff00) ^
   		(Td4[GETBYTE(t2, 0)] & 0x000000ff) ^
   		rk[1];
   	s2 =
   		(Td4[GETBYTE(t2, 3)] & 0xff000000) ^
   		(Td4[GETBYTE(t1, 2)] & 0x00ff0000) ^
   		(Td4[GETBYTE(t0, 1)] & 0x0000ff00) ^
   		(Td4[GETBYTE(t3, 0)] & 0x000000ff) ^
   		rk[2];
   	s3 =
   		(Td4[GETBYTE(t3, 3)] & 0xff000000) ^
   		(Td4[GETBYTE(t2, 2)] & 0x00ff0000) ^
   		(Td4[GETBYTE(t1, 1)] & 0x0000ff00) ^
   		(Td4[GETBYTE(t0, 0)] & 0x000000ff) ^
   		rk[3];

	Block::Put(xorBlock, outBlock)(s0)(s1)(s2)(s3);
}

NAMESPACE_END
