void RijndaelDecryption::ProcessBlock(const UCHAR *inBlock, UCHAR *outBlock) const
{
ULONG b0[4], b1[4];
GetBlockLittleEndian(inBlock, b0[0], b0[1], b0[2], b0[3]);
b0[0] ^= key[4 * k_len + 24];
b0[1] ^= key[4 * k_len + 25];
b0[2] ^= key[4 * k_len + 26];
b0[3] ^= key[4 * k_len + 27];
const ULONG *kp = key + 4 * (k_len + 5);
if(k_len > 6)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
if(k_len > 4)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_lround(b0, b1, kp);
PutBlockLittleEndian(outBlock, b0[0], b0[1], b0[2], b0[3]);
}
void rijndael_decrypt(rijndaelCtx *ctx, const uint32_t *in_blk,
uint32_t *out_blk)
{
uint32_t b0[4], b1[4], *kp;
uint32_t k_len = ctx->k_len;
uint32_t *e_key = ctx->e_key;
uint32_t *d_key = ctx->d_key;
b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24];
b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25];
b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26];
b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27];
kp = d_key + 4 * (k_len + 5);
if (k_len > 6) {
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
}
if (k_len > 4) {
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
}
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
i_nround(b1, b0, kp);
i_nround(b0, b1, kp);
i_nround(b1, b0, kp);
i_lround(b0, b1, kp);
out_blk[0] = io_swap(b0[0]);
out_blk[1] = io_swap(b0[1]);
out_blk[2] = io_swap(b0[2]);
out_blk[3] = io_swap(b0[3]);
}
void AES::decrypt(const u1byte in_blk[16], u1byte out_blk[16])
{
u4byte b0[4], b1[4], *kp;
b0[0] = u4byte_in(in_blk ) ^ e_key[4 * k_len + 24];
b0[1] = u4byte_in(in_blk + 4) ^ e_key[4 * k_len + 25];
b0[2] = u4byte_in(in_blk + 8) ^ e_key[4 * k_len + 26];
b0[3] = u4byte_in(in_blk + 12) ^ e_key[4 * k_len + 27];
kp = d_key + 4 * (k_len + 5);
if(k_len > 6)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
if(k_len > 4)
{
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
}
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_nround(b0, b1, kp);
i_nround(b1, b0, kp); i_lround(b0, b1, kp);
u4byte_out(out_blk, b0[0]); u4byte_out(out_blk + 4, b0[1]);
u4byte_out(out_blk + 8, b0[2]); u4byte_out(out_blk + 12, b0[3]);
}