rijndael.cpp

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// rijndael-alg-fst.c   v2.0   August '99
// Optimised ANSI C code
// authors: v1.0: Antoon Bosselaers
//          v2.0: Vincent Rijmen


/*
 *  taken from the 'aescrypt' project: www.sf.net/projects/aescrypt
 *  See LICENSE-EST for the license applicable to this file
 */


// 14.Dec.2005 Cirilo:  Removed silly hex keys; keys are now effectively unsigned char.

// KevinJ - TODO - What the hell is __UNUS?  It causes DevCPP not to compile.   I don't know what this is for so I'm taking it out entirely
/*
#if (defined(__GNUC__)  || defined(__GCCXML__))
#define __UNUS  __attribute__((unused))
#else
*/
#define __UNUS
//#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "Rijndael.h"

// KevinJ - Added this to just generate a random initialization vector
#include "Rand.h"

#define SC      ((BC - 4) >> 1)

#include "Rijndael-Boxes.h"

static int ROUNDS;

static word8 shifts[3][4][2] = {
  {
    {0, 0},
    {1, 3},
    {2, 2},
    {3, 1}
  },
   
  {
    {0, 0},
    {1, 5},
    {2, 4},
    {3, 3}
  },
   
  {
    {0, 0},
    {1, 7},
    {3, 5},
    {4, 4}
  }
}; 

word8 mul(word8 a, word8 b) {
   // multiply two elements of GF(2^m)
   // needed for MixColumn and InvMixColumn
   
        if (a && b)
                return Alogtable[(Logtable[a] + Logtable[b])%255];
        else
                return 0;
}

void KeyAddition(word8 a[4][4], word8 rk[4][4], word8 BC) {
        // XOR corresponding text input and round key input bytes
        int i, j;
        
        for(i = 0; i < BC; i++)
        for(j = 0; j < 4; j++)
                        a[i][j] ^= rk[i][j];
}

void ShiftRow(word8 a[4][4], word8 d, word8 BC) {
        // Row 0 remains unchanged
        // The other three rows are shifted a variable amount
        
        word8 tmp[4];
        int i, j;
        
        for(i = 1; i < 4; i++) {
                for(j = 0; j < BC; j++)
                        tmp[j] = a[(j + shifts[SC][i][d]) % BC][i];
                for(j = 0; j < BC; j++)
                        a[j][i] = tmp[j];
        }
}

void Substitution(word8 a[4][4], word8 box[256], word8 BC) {
        // Replace every byte of the input by the byte at that place
        // in the nonlinear S-box
        
        int i, j;
        
        for(i = 0; i < BC; i++)
                for(j = 0; j < 4; j++)
                        a[i][j] = box[a[i][j]] ;
}
   
void MixColumn(word8 a[4][4], word8 BC) {
      // Mix the four bytes of every column in a linear way
        
        word8 b[4][4];
        int i, j;
                
        for(j = 0; j < BC; j++)
                for(i = 0; i < 4; i++)
                        b[j][i] = mul(2,a[j][i])
                                ^ mul(3,a[j][(i + 1) % 4])
                                ^ a[j][(i + 2) % 4]
                                ^ a[j][(i + 3) % 4];
        for(i = 0; i < 4; i++)
                for(j = 0; j < BC; j++)
                        a[j][i] = b[j][i];
}

void InvMixColumn(word8 a[4][4], word8 BC) {
  // Mix the four bytes of every column in a linear way
        // This is the opposite operation of Mixcolumn
        
        int j;

        for(j = 0; j < BC; j++)
                *((word32*)a[j]) = *((word32*)U1[a[j][0]])
                                                                ^ *((word32*)U2[a[j][1]])
                                                                ^ *((word32*)U3[a[j][2]])
                                                                ^ *((word32*)U4[a[j][3]]);


}

int rijndaelKeySched (word8 k[MAXKC][4], int keyBits __UNUS, word8 W[MAXROUNDS+1][4][4])
{

        (void) keyBits;
        
        // Calculate the necessary round keys
        // The number of calculations depends on keyBits and blockBits
         
        int j, r, t, rconpointer = 0;
        word8 tk[MAXKC][4];
        int KC = ROUNDS - 6;

        for(j = KC-1; j >= 0; j--)
                *((word32*)tk[j]) = *((word32*)k[j]);
        r = 0;
        t = 0;
        // copy values into round key array
        for(j = 0; (j < KC) && (r < (ROUNDS+1)); ) {
                for (; (j < KC) && (t < 4); j++, t++)
                        *((word32*)W[r][t]) = *((word32*)tk[j]);
                if (t == 4) {
                        r++;
                        t = 0;
                }
        }
                
        while (r < (ROUNDS+1)) { // while not enough round key material calculated
                // calculate new values
                tk[0][0] ^= S[tk[KC-1][1]];
                tk[0][1] ^= S[tk[KC-1][2]];
                tk[0][2] ^= S[tk[KC-1][3]];
                tk[0][3] ^= S[tk[KC-1][0]];
                tk[0][0] ^= rcon[rconpointer++];

                if (KC != 8)
                        for(j = 1; j < KC; j++)
                                *((word32*)tk[j]) ^= *((word32*)tk[j-1]);
                else {
                        for(j = 1; j < KC/2; j++)
                                *((word32*)tk[j]) ^= *((word32*)tk[j-1]);
                        tk[KC/2][0] ^= S[tk[KC/2 - 1][0]];
                        tk[KC/2][1] ^= S[tk[KC/2 - 1][1]];
                        tk[KC/2][2] ^= S[tk[KC/2 - 1][2]];
                        tk[KC/2][3] ^= S[tk[KC/2 - 1][3]];
                        for(j = KC/2 + 1; j < KC; j++)
                                *((word32*)tk[j]) ^= *((word32*)tk[j-1]);
                }
                // copy values into round key array
                for(j = 0; (j < KC) && (r < (ROUNDS+1)); ) {
                        for (; (j < KC) && (t < 4); j++, t++)
                                *((word32*)W[r][t]) = *((word32*)tk[j]);
                        if (t == 4) {
                                r++;
                                t = 0;
                        }
                }
        }               

        return 0;
}

int rijndaelKeyEnctoDec (int keyBits __UNUS, word8 W[MAXROUNDS+1][4][4])
{
        (void) keyBits;

        int r;

        for (r = 1; r < ROUNDS; r++) {
                InvMixColumn(W[r], 4);
        }
        return 0;
}       

int rijndaelEncrypt (word8 a[16], word8 b[16], word8 rk[MAXROUNDS+1][4][4])
{
        // Encryption of one block. 
        
        int r;
   word8 temp[4][4];

    *((word32*)temp[0]) = *((word32*)a) ^ *((word32*)rk[0][0]);
    *((word32*)temp[1]) = *((word32*)(a+4)) ^ *((word32*)rk[0][1]);
    *((word32*)temp[2]) = *((word32*)(a+8)) ^ *((word32*)rk[0][2]);
    *((word32*)temp[3]) = *((word32*)(a+12)) ^ *((word32*)rk[0][3]);
    *((word32*)b) = *((word32*)T1[temp[0][0]])
           ^ *((word32*)T2[temp[1][1]])
           ^ *((word32*)T3[temp[2][2]]) 
           ^ *((word32*)T4[temp[3][3]]);
    *((word32*)(b+4)) = *((word32*)T1[temp[1][0]])
           ^ *((word32*)T2[temp[2][1]])
           ^ *((word32*)T3[temp[3][2]]) 
           ^ *((word32*)T4[temp[0][3]]);
    *((word32*)(b+8)) = *((word32*)T1[temp[2][0]])
           ^ *((word32*)T2[temp[3][1]])
           ^ *((word32*)T3[temp[0][2]]) 
           ^ *((word32*)T4[temp[1][3]]);
    *((word32*)(b+12)) = *((word32*)T1[temp[3][0]])
           ^ *((word32*)T2[temp[0][1]])
           ^ *((word32*)T3[temp[1][2]]) 
           ^ *((word32*)T4[temp[2][3]]);
   for(r = 1; r < ROUNDS-1; r++) {
                *((word32*)temp[0]) = *((word32*)b) ^ *((word32*)rk[r][0]);
                *((word32*)temp[1]) = *((word32*)(b+4)) ^ *((word32*)rk[r][1]);
                *((word32*)temp[2]) = *((word32*)(b+8)) ^ *((word32*)rk[r][2]);
                *((word32*)temp[3]) = *((word32*)(b+12)) ^ *((word32*)rk[r][3]);
   *((word32*)b) = *((word32*)T1[temp[0][0]])
           ^ *((word32*)T2[temp[1][1]])
           ^ *((word32*)T3[temp[2][2]]) 
           ^ *((word32*)T4[temp[3][3]]);
   *((word32*)(b+4)) = *((word32*)T1[temp[1][0]])
           ^ *((word32*)T2[temp[2][1]])
           ^ *((word32*)T3[temp[3][2]]) 
           ^ *((word32*)T4[temp[0][3]]);
   *((word32*)(b+8)) = *((word32*)T1[temp[2][0]])
           ^ *((word32*)T2[temp[3][1]])
           ^ *((word32*)T3[temp[0][2]]) 
           ^ *((word32*)T4[temp[1][3]]);
   *((word32*)(b+12)) = *((word32*)T1[temp[3][0]])
           ^ *((word32*)T2[temp[0][1]])
           ^ *((word32*)T3[temp[1][2]]) 
           ^ *((word32*)T4[temp[2][3]]);
   }
   // last round is special   
        *((word32*)temp[0]) = *((word32*)b) ^ *((word32*)rk[ROUNDS-1][0]);
        *((word32*)temp[1]) = *((word32*)(b+4)) ^ *((word32*)rk[ROUNDS-1][1]);
        *((word32*)temp[2]) = *((word32*)(b+8)) ^ *((word32*)rk[ROUNDS-1][2]);
        *((word32*)temp[3]) = *((word32*)(b+12)) ^ *((word32*)rk[ROUNDS-1][3]);
   b[0] = T1[temp[0][0]][1];
   b[1] = T1[temp[1][1]][1];
   b[2] = T1[temp[2][2]][1]; 
   b[3] = T1[temp[3][3]][1];
   b[4] = T1[temp[1][0]][1];
   b[5] = T1[temp[2][1]][1];
   b[6] = T1[temp[3][2]][1]; 
   b[7] = T1[temp[0][3]][1];
   b[8] = T1[temp[2][0]][1];
   b[9] = T1[temp[3][1]][1];
   b[10] = T1[temp[0][2]][1]; 
   b[11] = T1[temp[1][3]][1];
   b[12] = T1[temp[3][0]][1];
   b[13] = T1[temp[0][1]][1];
   b[14] = T1[temp[1][2]][1]; 
   b[15] = T1[temp[2][3]][1];
        *((word32*)b) ^= *((word32*)rk[ROUNDS][0]);
        *((word32*)(b+4)) ^= *((word32*)rk[ROUNDS][1]);
        *((word32*)(b+8)) ^= *((word32*)rk[ROUNDS][2]);
        *((word32*)(b+12)) ^= *((word32*)rk[ROUNDS][3]);

        return 0;
}

int rijndaelEncryptRound (word8 a[4][4], 
                word8 rk[MAXROUNDS+1][4][4], int rounds)
// Encrypt only a certain number of rounds.
// Only used in the Intermediate Value Known Answer Test.

{
        int r;
   word8 temp[4][4];


        // make number of rounds sane
        if (rounds > ROUNDS) rounds = ROUNDS;

        *((word32*)a[0]) = *((word32*)a[0]) ^ *((word32*)rk[0][0]);
        *((word32*)a[1]) = *((word32*)a[1]) ^ *((word32*)rk[0][1]);
        *((word32*)a[2]) = *((word32*)a[2]) ^ *((word32*)rk[0][2]);
        *((word32*)a[3]) = *((word32*)a[3]) ^ *((word32*)rk[0][3]);

        for(r = 1; (r <= rounds) && (r < ROUNDS); r++) {
                *((word32*)temp[0]) = *((word32*)T1[a[0][0]])
           ^ *((word32*)T2[a[1][1]])
           ^ *((word32*)T3[a[2][2]]) 
           ^ *((word32*)T4[a[3][3]]);
                *((word32*)temp[1]) = *((word32*)T1[a[1][0]])
           ^ *((word32*)T2[a[2][1]])
           ^ *((word32*)T3[a[3][2]]) 
           ^ *((word32*)T4[a[0][3]]);
                *((word32*)temp[2]) = *((word32*)T1[a[2][0]])
           ^ *((word32*)T2[a[3][1]])
           ^ *((word32*)T3[a[0][2]]) 
           ^ *((word32*)T4[a[1][3]]);
                *((word32*)temp[3]) = *((word32*)T1[a[3][0]])
           ^ *((word32*)T2[a[0][1]])
           ^ *((word32*)T3[a[1][2]]) 
           ^ *((word32*)T4[a[2][3]]);
                *((word32*)a[0]) = *((word32*)temp[0]) ^ *((word32*)rk[r][0]);
                *((word32*)a[1]) = *((word32*)temp[1]) ^ *((word32*)rk[r][1]);
                *((word32*)a[2]) = *((word32*)temp[2]) ^ *((word32*)rk[r][2]);
                *((word32*)a[3]) = *((word32*)temp[3]) ^ *((word32*)rk[r][3]);
   }
        if (rounds == ROUNDS) {
        // last round is special   
        temp[0][0] = T1[a[0][0]][1];
        temp[0][1] = T1[a[1][1]][1];
        temp[0][2] = T1[a[2][2]][1]; 
        temp[0][3] = T1[a[3][3]][1];
        temp[1][0] = T1[a[1][0]][1];
        temp[1][1] = T1[a[2][1]][1];
        temp[1][2] = T1[a[3][2]][1]; 
        temp[1][3] = T1[a[0][3]][1];
        temp[2][0] = T1[a[2][0]][1];
        temp[2][1] = T1[a[3][1]][1];
        temp[2][2] = T1[a[0][2]][1]; 
        temp[2][3] = T1[a[1][3]][1];
        temp[3][0] = T1[a[3][0]][1];
        temp[3][1] = T1[a[0][1]][1];
        temp[3][2] = T1[a[1][2]][1]; 
        temp[3][3] = T1[a[2][3]][1];
                *((word32*)a[0]) = *((word32*)temp[0]) ^ *((word32*)rk[ROUNDS][0]);
                *((word32*)a[1]) = *((word32*)temp[1]) ^ *((word32*)rk[ROUNDS][1]);
                *((word32*)a[2]) = *((word32*)temp[2]) ^ *((word32*)rk[ROUNDS][2]);
                *((word32*)a[3]) = *((word32*)temp[3]) ^ *((word32*)rk[ROUNDS][3]);
        }

        return 0;
}   


int rijndaelDecrypt (word8 a[16], word8 b[16], word8 rk[MAXROUNDS+1][4][4])
{
        int r;
   word8 temp[4][4];
        

    *((word32*)temp[0]) = *((word32*)a) ^ *((word32*)rk[ROUNDS][0]);
    *((word32*)temp[1]) = *((word32*)(a+4)) ^ *((word32*)rk[ROUNDS][1]);
    *((word32*)temp[2]) = *((word32*)(a+8)) ^ *((word32*)rk[ROUNDS][2]);
    *((word32*)temp[3]) = *((word32*)(a+12)) ^ *((word32*)rk[ROUNDS][3]);
    *((word32*)b) = *((word32*)T5[temp[0][0]])
           ^ *((word32*)T6[temp[3][1]])
           ^ *((word32*)T7[temp[2][2]]) 
           ^ *((word32*)T8[temp[1][3]]);
   *((word32*)(b+4)) = *((word32*)T5[temp[1][0]])
           ^ *((word32*)T6[temp[0][1]])
           ^ *((word32*)T7[temp[3][2]]) 
           ^ *((word32*)T8[temp[2][3]]);
   *((word32*)(b+8)) = *((word32*)T5[temp[2][0]])
           ^ *((word32*)T6[temp[1][1]])
           ^ *((word32*)T7[temp[0][2]]) 
           ^ *((word32*)T8[temp[3][3]]);
   *((word32*)(b+12)) = *((word32*)T5[temp[3][0]])
           ^ *((word32*)T6[temp[2][1]])
           ^ *((word32*)T7[temp[1][2]]) 
           ^ *((word32*)T8[temp[0][3]]);
   for(r = ROUNDS-1; r > 1; r--) {
                *((word32*)temp[0]) = *((word32*)b) ^ *((word32*)rk[r][0]);
                *((word32*)temp[1]) = *((word32*)(b+4)) ^ *((word32*)rk[r][1]);
                *((word32*)temp[2]) = *((word32*)(b+8)) ^ *((word32*)rk[r][2]);
                *((word32*)temp[3]) = *((word32*)(b+12)) ^ *((word32*)rk[r][3]);
                *((word32*)b) = *((word32*)T5[temp[0][0]])
           ^ *((word32*)T6[temp[3][1]])
           ^ *((word32*)T7[temp[2][2]]) 
           ^ *((word32*)T8[temp[1][3]]);
                *((word32*)(b+4)) = *((word32*)T5[temp[1][0]])
           ^ *((word32*)T6[temp[0][1]])
           ^ *((word32*)T7[temp[3][2]]) 
           ^ *((word32*)T8[temp[2][3]]);
                *((word32*)(b+8)) = *((word32*)T5[temp[2][0]])
           ^ *((word32*)T6[temp[1][1]])
           ^ *((word32*)T7[temp[0][2]]) 
           ^ *((word32*)T8[temp[3][3]]);
                *((word32*)(b+12)) = *((word32*)T5[temp[3][0]])
           ^ *((word32*)T6[temp[2][1]])
           ^ *((word32*)T7[temp[1][2]]) 
           ^ *((word32*)T8[temp[0][3]]);
   }
   // last round is special   
        *((word32*)temp[0]) = *((word32*)b) ^ *((word32*)rk[1][0]);
        *((word32*)temp[1]) = *((word32*)(b+4)) ^ *((word32*)rk[1][1]);
        *((word32*)temp[2]) = *((word32*)(b+8)) ^ *((word32*)rk[1][2]);
        *((word32*)temp[3]) = *((word32*)(b+12)) ^ *((word32*)rk[1][3]);
   b[0] = S5[temp[0][0]];
   b[1] = S5[temp[3][1]];
   b[2] = S5[temp[2][2]]; 
   b[3] = S5[temp[1][3]];
   b[4] = S5[temp[1][0]];
   b[5] = S5[temp[0][1]];
   b[6] = S5[temp[3][2]]; 
   b[7] = S5[temp[2][3]];
   b[8] = S5[temp[2][0]];
   b[9] = S5[temp[1][1]];
   b[10] = S5[temp[0][2]]; 
   b[11] = S5[temp[3][3]];
   b[12] = S5[temp[3][0]];
   b[13] = S5[temp[2][1]];
   b[14] = S5[temp[1][2]]; 
   b[15] = S5[temp[0][3]];
        *((word32*)b) ^= *((word32*)rk[0][0]);
        *((word32*)(b+4)) ^= *((word32*)rk[0][1]);
        *((word32*)(b+8)) ^= *((word32*)rk[0][2]);
        *((word32*)(b+12)) ^= *((word32*)rk[0][3]);

        return 0;
}


int rijndaelDecryptRound (word8 a[4][4],  
        word8 rk[MAXROUNDS+1][4][4], int rounds)
// Decrypt only a certain number of rounds.
// Only used in the Intermediate Value Known Answer Test.
// Operations rearranged such that the intermediate values
// of decryption correspond with the intermediate values
// of encryption.

{
        int r;
        

        // make number of rounds sane
        if (rounds > ROUNDS) rounds = ROUNDS;

        // First the special round:
        //   without InvMixColumn
        //   with extra KeyAddition
        
        KeyAddition(a,rk[ROUNDS],4);
        Substitution(a,Si,4);
        ShiftRow(a,1,4);              
        
        // ROUNDS-1 ordinary rounds
        
        for(r = ROUNDS-1; r > rounds; r--) {
                KeyAddition(a,rk[r],4);
                InvMixColumn(a,4);      
                Substitution(a,Si,4);
                ShiftRow(a,1,4);                
        }
        
        if (rounds == 0) {
                // End with the extra key addition
                        
                KeyAddition(a,rk[0],4);
        }    

        return 0;
}

/*** End Rijndael algorithm,  Begin the AES Interface ***/


int makeKey(keyInstance *key, BYTE direction, int keyByteLen, char *keyMaterial)
{
        word8 k[MAXKC][4];
        int i;
        int keyLen = keyByteLen*8;
        
        if (key == NULL) {
                return BAD_KEY_INSTANCE;
        }

        if ((direction == DIR_ENCRYPT) || (direction == DIR_DECRYPT)) {
                key->direction = direction;
        } else {
                return BAD_KEY_DIR;
        }

        if ((keyLen == 128) || (keyLen == 192) || (keyLen == 256)) { 
                key->keyLen = keyLen;
        } else {
                return BAD_KEY_MAT;
        }

        if ( keyMaterial ) {
                strncpy(key->keyMaterial, keyMaterial, keyByteLen);
        } else {
                return BAD_KEY_MAT;
        }

        ROUNDS = keyLen/32 + 6;

        // initialize key schedule:
        for(i = 0; i < key->keyLen/8; i++) {
                k[i / 4][i % 4] = (word8) key->keyMaterial[i]; 
        }
        rijndaelKeySched (k, key->keyLen, key->keySched);
        if (direction == DIR_DECRYPT)
                rijndaelKeyEnctoDec (key->keyLen, key->keySched);

        return TRUE;
}

int cipherInit(cipherInstance *cipher, BYTE mode, char *IV)
{
        int i;
        
        if ((mode == MODE_ECB) || (mode == MODE_CBC) || (mode == MODE_CFB1)) {
                cipher->mode = mode;
        } else {
                return BAD_CIPHER_MODE;
        }
        

        if (IV != NULL) {
                for(i = 0; i < 16; i++) cipher->IV[i] = IV[i];
        }
        else
        {
                // KevinJ - Added this to just generate a random initialization vector
                for(i = 0; i < 16; i++)
                        cipher->IV[i]=(BYTE)randomMT();
        }

        return TRUE;
}


int blockEncrypt(cipherInstance *cipher,
        keyInstance *key, BYTE *input, int inputByteLen, BYTE *outBuffer)
{
        int i, k, numBlocks;
        word8 block[16], iv[4][4];
        int inputLen = inputByteLen*8;

        if (cipher == NULL ||
                key == NULL ||
                key->direction == DIR_DECRYPT) {
                return BAD_CIPHER_STATE;
        }
        

        numBlocks = inputLen/128;
        
        switch (cipher->mode) {
        case MODE_ECB: 
                for (i = numBlocks; i > 0; i--) {
                        
                        rijndaelEncrypt (input, outBuffer, key->keySched);
                        
                        input += 16;
                        outBuffer += 16;
                }
                break;
                
        case MODE_CBC:
#if STRICT_ALIGN 
                memcpy(block,cipher->IV,16); 
#else
                *((word32*)block) =  *((word32*)(cipher->IV));
                *((word32*)(block+4)) =  *((word32*)(cipher->IV+4));
                *((word32*)(block+8)) =  *((word32*)(cipher->IV+8));
                *((word32*)(block+12)) =  *((word32*)(cipher->IV+12));
#endif
                
                for (i = numBlocks; i > 0; i--) {
                        *((word32*)block) ^= *((word32*)(input));
                        *((word32*)(block+4)) ^= *((word32*)(input+4));
                        *((word32*)(block+8)) ^= *((word32*)(input+8));
                        *((word32*)(block+12)) ^= *((word32*)(input+12));

                        rijndaelEncrypt (block, outBuffer, key->keySched);
                        
                        input += 16;
                        outBuffer += 16;
                }
                break;
        
        case MODE_CFB1:
#if STRICT_ALIGN 
                memcpy(iv,cipher->IV,16); 
#else
                *((word32*)iv[0]) = *((word32*)(cipher->IV));
                *((word32*)iv[1]) = *((word32*)(cipher->IV+4));
                *((word32*)iv[2]) = *((word32*)(cipher->IV+8));
                *((word32*)iv[3]) = *((word32*)(cipher->IV+12));
#endif
                for (i = numBlocks; i > 0; i--) {
                        for (k = 0; k < 128; k++) {
                                *((word32*)block) = *((word32*)iv[0]);
                                *((word32*)(block+4)) = *((word32*)iv[1]);
                                *((word32*)(block+8)) = *((word32*)iv[2]);
                                *((word32*)(block+12)) = *((word32*)iv[3]);

                                rijndaelEncrypt (block, block, key->keySched);
                                outBuffer[k/8] ^= (block[0] & 0x80) >> (k & 7);
                                iv[0][0] = (iv[0][0] << 1) | (iv[0][1] >> 7);
                                iv[0][1] = (iv[0][1] << 1) | (iv[0][2] >> 7);
                                iv[0][2] = (iv[0][2] << 1) | (iv[0][3] >> 7);
                                iv[0][3] = (iv[0][3] << 1) | (iv[1][0] >> 7);
                                iv[1][0] = (iv[1][0] << 1) | (iv[1][1] >> 7);
                                iv[1][1] = (iv[1][1] << 1) | (iv[1][2] >> 7);
                                iv[1][2] = (iv[1][2] << 1) | (iv[1][3] >> 7);
                                iv[1][3] = (iv[1][3] << 1) | (iv[2][0] >> 7);
                                iv[2][0] = (iv[2][0] << 1) | (iv[2][1] >> 7);
                                iv[2][1] = (iv[2][1] << 1) | (iv[2][2] >> 7);
                                iv[2][2] = (iv[2][2] << 1) | (iv[2][3] >> 7);
                                iv[2][3] = (iv[2][3] << 1) | (iv[3][0] >> 7);
                                iv[3][0] = (iv[3][0] << 1) | (iv[3][1] >> 7);
                                iv[3][1] = (iv[3][1] << 1) | (iv[3][2] >> 7);
                                iv[3][2] = (iv[3][2] << 1) | (iv[3][3] >> 7);
                                iv[3][3] = (word8)((iv[3][3] << 1) | (outBuffer[k/8] >> (7-(k&7))) & 1);
                        }
                }
                break;
        
        default:
                return BAD_CIPHER_STATE;
        }
        
        return numBlocks*128;
}

int blockDecrypt(cipherInstance *cipher,
        keyInstance *key, BYTE *input, int inputByteLen, BYTE *outBuffer)
{
        int i, k, numBlocks;
        word8 block[16], iv[4][4];
        int inputLen = inputByteLen*8;

        if (cipher == NULL ||
                key == NULL ||
                cipher->mode != MODE_CFB1 && key->direction == DIR_ENCRYPT) {
                return BAD_CIPHER_STATE;
        }
        

        numBlocks = inputLen/128;
        
        switch (cipher->mode) {
        case MODE_ECB: 
                for (i = numBlocks; i > 0; i--) { 

                        rijndaelDecrypt (input, outBuffer, key->keySched);

                        input += 16;
                        outBuffer += 16;

                }
                break;
                
        case MODE_CBC:
                // first block 

                rijndaelDecrypt (input, block, key->keySched);
#if STRICT_ALIGN
                memcpy(outBuffer,cipher->IV,16); 
                *((word32*)(outBuffer)) ^= *((word32*)block);
                *((word32*)(outBuffer+4)) ^= *((word32*)(block+4));
                *((word32*)(outBuffer+8)) ^= *((word32*)(block+8));
                *((word32*)(outBuffer+12)) ^= *((word32*)(block+12));
#else
                *((word32*)(outBuffer)) = *((word32*)block) ^ *((word32*)(cipher->IV));
                *((word32*)(outBuffer+4)) = *((word32*)(block+4)) ^ *((word32*)(cipher->IV+4));
                *((word32*)(outBuffer+8)) = *((word32*)(block+8)) ^ *((word32*)(cipher->IV+8));
                *((word32*)(outBuffer+12)) = *((word32*)(block+12)) ^ *((word32*)(cipher->IV+12));
#endif
                
                // next blocks
                for (i = numBlocks-1; i > 0; i--) { 
                
                        rijndaelDecrypt (input, block, key->keySched);
                        
                        *((word32*)(outBuffer+16)) = *((word32*)block) ^
                                        *((word32*)(input-16));
                        *((word32*)(outBuffer+20)) = *((word32*)(block+4)) ^
                                        *((word32*)(input-12));
                        *((word32*)(outBuffer+24)) = *((word32*)(block+8)) ^
                                        *((word32*)(input-8));
                        *((word32*)(outBuffer+28)) = *((word32*)(block+12)) ^
                                        *((word32*)(input-4));
                        
                        input += 16;
                        outBuffer += 16;
                }
                break;
        
        case MODE_CFB1:
#if STRICT_ALIGN 
                memcpy(iv,cipher->IV,16); 
#else
                *((word32*)iv[0]) = *((word32*)(cipher->IV));
                *((word32*)iv[1]) = *((word32*)(cipher->IV+4));
                *((word32*)iv[2]) = *((word32*)(cipher->IV+8));
                *((word32*)iv[3]) = *((word32*)(cipher->IV+12));
#endif
                for (i = numBlocks; i > 0; i--) {
                        for (k = 0; k < 128; k++) {
                                *((word32*)block) = *((word32*)iv[0]);
                                *((word32*)(block+4)) = *((word32*)iv[1]);
                                *((word32*)(block+8)) = *((word32*)iv[2]);
                                *((word32*)(block+12)) = *((word32*)iv[3]);

                                rijndaelEncrypt (block, block, key->keySched);
                                iv[0][0] = (iv[0][0] << 1) | (iv[0][1] >> 7);
                                iv[0][1] = (iv[0][1] << 1) | (iv[0][2] >> 7);
                                iv[0][2] = (iv[0][2] << 1) | (iv[0][3] >> 7);
                                iv[0][3] = (iv[0][3] << 1) | (iv[1][0] >> 7);
                                iv[1][0] = (iv[1][0] << 1) | (iv[1][1] >> 7);
                                iv[1][1] = (iv[1][1] << 1) | (iv[1][2] >> 7);
                                iv[1][2] = (iv[1][2] << 1) | (iv[1][3] >> 7);
                                iv[1][3] = (iv[1][3] << 1) | (iv[2][0] >> 7);
                                iv[2][0] = (iv[2][0] << 1) | (iv[2][1] >> 7);
                                iv[2][1] = (iv[2][1] << 1) | (iv[2][2] >> 7);
                                iv[2][2] = (iv[2][2] << 1) | (iv[2][3] >> 7);
                                iv[2][3] = (iv[2][3] << 1) | (iv[3][0] >> 7);
                                iv[3][0] = (iv[3][0] << 1) | (iv[3][1] >> 7);
                                iv[3][1] = (iv[3][1] << 1) | (iv[3][2] >> 7);
                                iv[3][2] = (iv[3][2] << 1) | (iv[3][3] >> 7);
                                iv[3][3] = (word8)((iv[3][3] << 1) | (input[k/8] >> (7-(k&7))) & 1);
                                outBuffer[k/8] ^= (block[0] & 0x80) >> (k & 7);
                        }
                }
                break;

        default:
                return BAD_CIPHER_STATE;
        }
        
        return numBlocks*128;
}


int cipherUpdateRounds(cipherInstance *cipher,
        keyInstance *key, BYTE *input, int inputLen __UNUS, BYTE *outBuffer, int rounds)
{
        (void) inputLen;

        int j;
        word8 block[4][4];

        if (cipher == NULL ||
                key == NULL) {
                return BAD_CIPHER_STATE;
        }

        for (j = 3; j >= 0; j--) {
                // parse input stream into rectangular array
                *((word32*)block[j]) = *((word32*)(input+4*j));
        }

        switch (key->direction) {
        case DIR_ENCRYPT:
                rijndaelEncryptRound (block, key->keySched, rounds);
        break;
                
        case DIR_DECRYPT:
                rijndaelDecryptRound (block, key->keySched, rounds);
        break;
                
        default: return BAD_KEY_DIR;
        } 

        for (j = 3; j >= 0; j--) {
                // parse rectangular array into output ciphertext bytes
                *((word32*)(outBuffer+4*j)) = *((word32*)block[j]);
        }
        
        return TRUE;
}