__crypto_aead_cast
unsigned long auth_tag_len = crypto_aead_authsize(__crypto_aead_cast(tfm));
struct crypto_aead *aead = __crypto_aead_cast(tfm);
struct crypto_aead *aead = __crypto_aead_cast(tfm);
crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
aead_request_set_tfm(req, __crypto_aead_cast(tfm));
crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
struct crypto_aead *aead = __crypto_aead_cast(tfm);
return __crypto_aead_cast(req->base.tfm);