-void hmac_sha256_vector(const u8 *key, size_t key_len, size_t num_elem,
- const u8 *addr[], const size_t *len, u8 *mac);
-void hmac_sha256(const u8 *key, size_t key_len, const u8 *data,
- size_t data_len, u8 *mac);
-void sha256_prf(const u8 *key, size_t key_len, const char *label,
- const u8 *data, size_t data_len, u8 *buf, size_t buf_len);
+int hmac_sha256_vector(const u8 *key, size_t key_len, size_t num_elem,
+ const u8 *addr[], const size_t *len, u8 *mac);
+int hmac_sha256(const u8 *key, size_t key_len, const u8 *data,
+ size_t data_len, u8 *mac);
+int sha256_prf(const u8 *key, size_t key_len, const char *label,
+ const u8 *data, size_t data_len, u8 *buf, size_t buf_len);
+int sha256_prf_bits(const u8 *key, size_t key_len, const char *label,
+ const u8 *data, size_t data_len, u8 *buf,
+ size_t buf_len_bits);
+void tls_prf_sha256(const u8 *secret, size_t secret_len,
+ const char *label, const u8 *seed, size_t seed_len,
+ u8 *out, size_t outlen);
+int hmac_sha256_kdf(const u8 *secret, size_t secret_len,
+ const char *label, const u8 *seed, size_t seed_len,
+ u8 *out, size_t outlen);