hmac_md5_preparekey
hmac_md5_preparekey(HMAC_MD5_KEY(tfm), raw_key, keylen);
void hmac_md5_preparekey(struct hmac_md5_key *key,
EXPORT_SYMBOL_GPL(hmac_md5_preparekey);
#define HMAC_PREPAREKEY hmac_md5_preparekey