void RunEncryptionKeySchedule(uint8_t *key, uint8_t *roundKeys)
{
int32_t i;
uint32_t j, k;
uint32_t A, B;
uint32_t L[c];
uint32_t *RoundKeys = (uint32_t *)roundKeys;
/* Initialize L, then S, then mix key into S */
L[c - 1] = 0;
for(i = KEY_SIZE - 1; i != -1; i--)
{
L[i / u] = (L[i / u] << 8) + key[i];
}
RoundKeys[0] = P;
for(i = 1; i < t; i++)
{
RoundKeys[i] = RoundKeys[i - 1] + Q;
}
A = B = i = j = 0;
for(k = 0; k < 3 * t; k++)
{
A = RoundKeys[i] = RC5_ROTL(RoundKeys[i] + (A + B), 3);
B = L[j] = RC5_ROTL(L[j] + (A + B), (A + B));
i = (i + 1) % t;
j = (j + 1) % c;
}
}
// Encrypt data block
// Parameters:
// pt - input data
// ct - encrypt data
void RC5Simple::RC5_EncryptBlock(RC5_TWORD *pt, RC5_TWORD *ct)
{
RC5_TWORD i;
RC5_TWORD a=pt[0]+rc5_s[0];
RC5_TWORD b=pt[1]+rc5_s[1];
for(i=1; i<=RC5_R; i++)
{
a = RC5_ROTL(a^b, b)+rc5_s[2*i];
b = RC5_ROTL(b^a, a)+rc5_s[2*i+1];
}
ct[0] = a;
ct[1] = b;
}
// Setup secret key
// Parameters:
// key - secret input key[RC5_B]
void RC5Simple::RC5_Setup(unsigned char *key)
{
RC5_LOG(( "RC5_Setup, set key to: " ));
for(int i=0; i<RC5_B; i++)
RC5_LOG(( "%.2X", key[i] ));
RC5_LOG(( "\n" ));
int i, j, k;
RC5_TWORD u=RC5_W/8, a, b, l[RC5_C];
// Initialize l[], then rc5_s[], then mix key into rc5_s[]
for(i=RC5_B-1, l[RC5_C-1]=0; i!=-1; i--)
l[i/u] = (l[i/u]<<8)+key[i];
RC5_LOG(( "RC5_Setup, l[]: " ));
for(int i=0; i<RC5_C; i++)
RC5_LOG(( "%.2X", l[i] ));
RC5_LOG(( "\n" ));
for(rc5_s[0]=rc5_p,i=1; i<RC5_T; i++)
rc5_s[i] = rc5_s[i-1]+rc5_q;
RC5_LOG(( "RC5_Setup, rc5_s[]: " ));
for(int i=0; i<RC5_T; i++)
RC5_LOG(( "%.2X", rc5_s[i] ));
RC5_LOG(( "\n" ));
// 3*t > 3*c
for(a=b=i=j=k=0; k<3*RC5_T; k++, i=(i+1)%RC5_T, j=(j+1)%RC5_C)
{
a = rc5_s[i] = RC5_ROTL(rc5_s[i]+(a+b),3);
b = l[j] = RC5_ROTL(l[j]+(a+b),(a+b));
}
RC5_LOG(( "RC5_Setup, mix rc5_s[]: " ));
for(int i=0; i<RC5_T; i++)
RC5_LOG(( "%.2X", rc5_s[i] ));
RC5_LOG(( "\n" ));
}
void Encrypt(uint8_t *block, uint8_t *roundKeys)
{
uint32_t *Block = (uint32_t *)block;
uint32_t *RoundKeys = (uint32_t *)roundKeys;
Block[0] = Block[0] + READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[0]);
Block[1] = Block[1] + READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[1]);
/* Round 1 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[2]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[3]);
/* Round 2 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[4]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[5]);
/* Round 3 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[6]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[7]);
/* Round 4 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[8]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[9]);
/* Round 5 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[10]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[11]);
/* Round 6 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[12]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[13]);
/* Round 7 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[14]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[15]);
/* Round 8 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[16]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[17]);
/* Round 9 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[18]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[19]);
/* Round 10 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[20]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[21]);
/* Round 11 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[22]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[23]);
/* Round 12 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[24]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[25]);
/* Round 13 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[26]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[27]);
/* Round 14 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[28]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[29]);
/* Round 15 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[30]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[31]);
/* Round 16 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[32]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[33]);
/* Round 17 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[34]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[35]);
/* Round 18 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[36]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[37]);
/* Round 19 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[38]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[39]);
/* Round 20 */
Block[0] = RC5_ROTL(Block[0] ^ Block[1], Block[1]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[40]);
Block[1] = RC5_ROTL(Block[1] ^ Block[0], Block[0]) +
READ_ROUND_KEY_DOUBLE_WORD(RoundKeys[41]);
}
