static int crypto_ofb_crypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
const unsigned int bsize = crypto_cipher_blocksize(cipher);
struct skcipher_walk walk;
int err;
err = skcipher_walk_virt(&walk, req, false);
while (walk.nbytes >= bsize) {
const u8 *src = walk.src.virt.addr;
u8 *dst = walk.dst.virt.addr;
u8 * const iv = walk.iv;
unsigned int nbytes = walk.nbytes;
do {
crypto_cipher_encrypt_one(cipher, iv, iv);
crypto_xor_cpy(dst, src, iv, bsize);
dst += bsize;
src += bsize;
} while ((nbytes -= bsize) >= bsize);
err = skcipher_walk_done(&walk, nbytes);
}
if (walk.nbytes) {
crypto_cipher_encrypt_one(cipher, walk.iv, walk.iv);
crypto_xor_cpy(walk.dst.virt.addr, walk.src.virt.addr, walk.iv,
walk.nbytes);
err = skcipher_walk_done(&walk, 0);
}
return err;
}
static int crypto_ctr_crypt(struct skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
const unsigned int bsize = crypto_cipher_blocksize(cipher);
struct skcipher_walk walk;
unsigned int nbytes;
int err;
err = skcipher_walk_virt(&walk, req, false);
while (walk.nbytes >= bsize) {
if (walk.src.virt.addr == walk.dst.virt.addr)
nbytes = crypto_ctr_crypt_inplace(&walk, cipher);
else
nbytes = crypto_ctr_crypt_segment(&walk, cipher);
err = skcipher_walk_done(&walk, nbytes);
}
if (walk.nbytes) {
crypto_ctr_crypt_final(&walk, cipher);
err = skcipher_walk_done(&walk, 0);
}
return err;
}
