void twofish_enc_blk_ctr_3way(void *ctx, u128 *dst, const u128 *src,
u128 *iv)
{
be128 ctrblks[3];
if (dst != src) {
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
}
u128_to_be128(&ctrblks[0], iv);
u128_inc(iv);
u128_to_be128(&ctrblks[1], iv);
u128_inc(iv);
u128_to_be128(&ctrblks[2], iv);
u128_inc(iv);
twofish_enc_blk_xor_3way(ctx, (u8 *)dst, (u8 *)ctrblks);
}
void twofish_enc_blk_ctr(void *ctx, u128 *dst, const u128 *src, u128 *iv)
{
be128 ctrblk;
if (dst != src)
*dst = *src;
u128_to_be128(&ctrblk, iv);
u128_inc(iv);
twofish_enc_blk(ctx, (u8 *)&ctrblk, (u8 *)&ctrblk);
u128_xor(dst, dst, (u128 *)&ctrblk);
}
static void twofish_enc_blk_ctr_xway(void *ctx, u128 *dst, const u128 *src,
u128 *iv)
{
be128 ctrblks[TWOFISH_PARALLEL_BLOCKS];
unsigned int i;
for (i = 0; i < TWOFISH_PARALLEL_BLOCKS; i++) {
if (dst != src)
dst[i] = src[i];
u128_to_be128(&ctrblks[i], iv);
u128_inc(iv);
}
twofish_enc_blk_xway_xor(ctx, (u8 *)dst, (u8 *)ctrblks);
}
static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
struct blkcipher_walk *walk)
{
struct twofish_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
unsigned int bsize = TF_BLOCK_SIZE;
unsigned int nbytes = walk->nbytes;
u128 *src = (u128 *)walk->src.virt.addr;
u128 *dst = (u128 *)walk->dst.virt.addr;
u128 ctrblk;
be128 ctrblocks[3];
be128_to_u128(&ctrblk, (be128 *)walk->iv);
/* Process three block batch */
if (nbytes >= bsize * 3) {
do {
if (dst != src) {
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
}
/* create ctrblks for parallel encrypt */
u128_to_be128(&ctrblocks[0], &ctrblk);
u128_inc(&ctrblk);
u128_to_be128(&ctrblocks[1], &ctrblk);
u128_inc(&ctrblk);
u128_to_be128(&ctrblocks[2], &ctrblk);
u128_inc(&ctrblk);
twofish_enc_blk_xor_3way(ctx, (u8 *)dst,
(u8 *)ctrblocks);
src += 3;
dst += 3;
nbytes -= bsize * 3;
} while (nbytes >= bsize * 3);
if (nbytes < bsize)
goto done;
}
/* Handle leftovers */
do {
if (dst != src)
*dst = *src;
u128_to_be128(&ctrblocks[0], &ctrblk);
u128_inc(&ctrblk);
twofish_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
u128_xor(dst, dst, (u128 *)ctrblocks);
src += 1;
dst += 1;
nbytes -= bsize;
} while (nbytes >= bsize);
done:
u128_to_be128((be128 *)walk->iv, &ctrblk);
return nbytes;
}
