+int tls_version_ok(u16 ver);
+const char * tls_version_str(u16 ver);
+int tls_prf(u16 ver, const u8 *secret, size_t secret_len, const char *label,
+ const u8 *seed, size_t seed_len, u8 *out, size_t outlen);
+int tlsv12_key_x_server_params_hash(u16 tls_version, u8 hash_Alg,
+ const u8 *client_random,
+ const u8 *server_random,
+ const u8 *server_params,
+ size_t server_params_len, u8 *hash);
+int tls_key_x_server_params_hash(u16 tls_version, const u8 *client_random,
+ const u8 *server_random,
+ const u8 *server_params,
+ size_t server_params_len, u8 *hash);
+int tls_verify_signature(u16 tls_version, struct crypto_public_key *pk,
+ const u8 *data, size_t data_len,
+ const u8 *pos, size_t len, u8 *alert);