char rijndaelEncrypt ()
{
/* Encryption of one block.
*/
char r;
/* begin with a key addition
*/
KeyAddition ( 0 );
/* ROUNDS-1 ordinary rounds
*/
for ( r = 1; r < ROUNDS; r++ )
{
SubstitutionS();
ShiftRow0();
MixColumn();
KeyAddition ( r );
}
/* Last round is special: there is no MixColumn
*/
SubstitutionS();
ShiftRow0();
KeyAddition ( ROUNDS );
return 0;
}
int rijndaelDecryptRound (word8 a[4][MAXBC], int keyBits, int blockBits,
word8 rk[MAXROUNDS+1][4][MAXBC], 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, BC, ROUNDS;
switch (blockBits) {
case 128: BC = 4; break;
case 192: BC = 6; break;
case 256: BC = 8; break;
default : return (-2);
}
switch (keyBits >= blockBits ? keyBits : blockBits) {
case 128: ROUNDS = 10; break;
case 192: ROUNDS = 12; break;
case 256: ROUNDS = 14; break;
default : return (-3); /* this cannot happen */
}
/* make number of rounds sane */
if (rounds > ROUNDS) rounds = ROUNDS;
/* First the special round:
* without InvMixColumn
* with extra KeyAddition
*/
KeyAddition(a,rk[ROUNDS],BC);
Substitution(a,Si,BC);
ShiftRow(a,1,BC);
/* ROUNDS-1 ordinary rounds
*/
for(r = ROUNDS-1; r > rounds; r--) {
KeyAddition(a,rk[r],BC);
InvMixColumn(a,BC);
Substitution(a,Si,BC);
ShiftRow(a,1,BC);
}
if (rounds == 0) {
/* End with the extra key addition
*/
KeyAddition(a,rk[0],BC);
}
return 0;
}
int _rijndaelDecrypt (word8 a[4][MAXBC], int keyBits, int blockBits, word8 rk[MAXROUNDS+1][4][MAXBC])
{
int r, BC, ROUNDS;
switch (blockBits) {
case 128: BC = 4; break;
case 192: BC = 6; break;
case 256: BC = 8; break;
default : return (-2);
}
switch (keyBits >= blockBits ? keyBits : blockBits) {
case 128: ROUNDS = 10; break;
case 192: ROUNDS = 12; break;
case 256: ROUNDS = 14; break;
default : return (-3); /* this cannot happen */
}
/* To decrypt: apply the inverse operations of the encrypt routine,
* in opposite order
*
* (KeyAddition is an involution: it 's equal to its inverse)
* (the inverse of Substitution with table S is Substitution with the inverse table of S)
* (the inverse of Shiftrow is Shiftrow over a suitable distance)
*/
/* First the special round:
* without InvMixColumn
* with extra KeyAddition
*/
KeyAddition(a,rk[ROUNDS],BC);
Substitution(a,Si,BC);
ShiftRow(a,1,BC);
/* ROUNDS-1 ordinary rounds
*/
for(r = ROUNDS-1; r > 0; r--) {
KeyAddition(a,rk[r],BC);
InvMixColumn(a,BC);
Substitution(a,Si,BC);
ShiftRow(a,1,BC);
}
/* End with the extra key addition
*/
KeyAddition(a,rk[0],BC);
return 0;
}
int rijndaelEncryptRound (word8 a[4][MAXBC], int keyBits, int blockBits,
word8 rk[MAXROUNDS+1][4][MAXBC], int rounds)
/* Encrypt only a certain number of rounds.
* Only used in the Intermediate Value Known Answer Test.
*/
{
int r, BC, ROUNDS;
switch (blockBits) {
case 128: BC = 4; break;
case 192: BC = 6; break;
case 256: BC = 8; break;
default : return (-2);
}
switch (keyBits >= blockBits ? keyBits : blockBits) {
case 128: ROUNDS = 10; break;
case 192: ROUNDS = 12; break;
case 256: ROUNDS = 14; break;
default : return (-3); /* this cannot happen */
}
/* make number of rounds sane */
if (rounds > ROUNDS) rounds = ROUNDS;
/* begin with a key addition
*/
KeyAddition(a,rk[0],BC);
/* at most ROUNDS-1 ordinary rounds
*/
for(r = 1; (r <= rounds) && (r < ROUNDS); r++) {
Substitution(a,S,BC);
ShiftRow(a,0,BC);
MixColumn(a,BC);
KeyAddition(a,rk[r],BC);
}
/* if necessary, do the last, special, round:
*/
if (rounds == ROUNDS) {
Substitution(a,S,BC);
ShiftRow(a,0,BC);
KeyAddition(a,rk[ROUNDS],BC);
}
return 0;
}
int _rijndaelEncrypt (word8 a[4][MAXBC], int keyBits, int blockBits, word8 rk[MAXROUNDS+1][4][MAXBC])
{
/* Encryption of one block.
*/
int r, BC, ROUNDS;
switch (blockBits) {
case 128: BC = 4; break;
case 192: BC = 6; break;
case 256: BC = 8; break;
default : return (-2);
}
switch (keyBits >= blockBits ? keyBits : blockBits) {
case 128: ROUNDS = 10; break;
case 192: ROUNDS = 12; break;
case 256: ROUNDS = 14; break;
default : return (-3); /* this cannot happen */
}
/* begin with a key addition
*/
KeyAddition(a,rk[0],BC);
/* ROUNDS-1 ordinary rounds
*/
for(r = 1; r < ROUNDS; r++) {
Substitution(a,S,BC);
ShiftRow(a,0,BC);
MixColumn(a,BC);
KeyAddition(a,rk[r],BC);
}
/* Last round is special: there is no MixColumn
*/
Substitution(a,S,BC);
ShiftRow(a,0,BC);
KeyAddition(a,rk[ROUNDS],BC);
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;
}
char rijndaelDecrypt ()
{
char r;
/* To decrypt: apply the inverse operations of the encrypt routine,
* in opposite order
*
* (KeyAddition is an involution: it 's equal to its inverse)
* (the inverse of Substitution with table S is Substitution with the inverse table of S)
* (the inverse of Shiftrow is Shiftrow over a suitable distance)
*/
/* First the special round:
* without InvMixColumn
* with extra KeyAddition
*/
KeyAddition ( ROUNDS );
SubstitutionSi();
ShiftRow1();
/* ROUNDS-1 ordinary rounds
*/
for ( r = ROUNDS - 1; r > 0; r-- )
{
KeyAddition ( r );
InvMixColumn();
SubstitutionSi();
ShiftRow1();
}
/* End with the extra key addition
*/
KeyAddition ( 0 );
return 0;
}
