tls-crypto: Rename parameter to be more consistent

Also add missing parameter in documentation of calculate_finished method.

src/libtls/tls_crypto.c

@@ -1867,7 +1867,7 @@ METHOD(tls_crypto_t, calculate_finished_legacy, bool,
 }
 
 METHOD(tls_crypto_t, calculate_finished, bool,
-	private_tls_crypto_t *this, bool is_server, chunk_t *out)
+	private_tls_crypto_t *this, bool server, chunk_t *out)
 {
 	chunk_t finished_key, finished_hash;
 
@@ -1880,7 +1880,7 @@ METHOD(tls_crypto_t, calculate_finished, bool,
 		DBG1(DBG_TLS, "creating hash of handshake failed");
 		return FALSE;
 	}
-	if (!this->hkdf->derive_finished(this->hkdf, is_server, &finished_key))
+	if (!this->hkdf->derive_finished(this->hkdf, server, &finished_key))
 	{
 		DBG1(DBG_TLS, "generating finished key failed");
 		chunk_clear(&finished_hash);

src/libtls/tls_crypto.h

@@ -563,10 +563,11 @@ struct tls_crypto_t {
 	/**
 	 * Calculate the data of a TLS finished message.
 	 *
+	 * @param server		Whether the server or client finish message is calculated
 	 * @param out			buffer to write finished data to
 	 * @return				TRUE if calculation successful
 	 */
-	bool (*calculate_finished)(tls_crypto_t *this, bool is_server,
+	bool (*calculate_finished)(tls_crypto_t *this, bool server,
 							   chunk_t *out);
 
 	/**

src/libtls/tls_hkdf.c

@@ -476,12 +476,12 @@ METHOD(tls_hkdf_t, generate_secret, bool,
  * Derive keys/IVs from the current traffic secrets.
  */
 static bool get_shared_label_keys(private_tls_hkdf_t *this, chunk_t label,
-								  bool is_server, size_t length, chunk_t *key)
+								  bool server, size_t length, chunk_t *key)
 {
 	chunk_t result = chunk_empty, secret;
 
-	secret = is_server ? this->server_traffic_secret
-					   : this->client_traffic_secret;
+	secret = server ? this->server_traffic_secret
+					: this->client_traffic_secret;
 
 	if (!expand_label(this, secret, label, chunk_empty, length, &result))
 	{
@@ -516,10 +516,10 @@ METHOD(tls_hkdf_t, derive_iv, bool,
 }
 
 METHOD(tls_hkdf_t, derive_finished, bool,
-	private_tls_hkdf_t *this, bool is_server, chunk_t *finished)
+	private_tls_hkdf_t *this, bool server, chunk_t *finished)
 {
 	return get_shared_label_keys(this, chunk_from_str("finished"),
-								 is_server,
+								 server,
 								 this->hasher->get_hash_size(this->hasher),
 								 finished);
 }

src/libtls/tls_hkdf.h

@@ -106,11 +106,11 @@ struct tls_hkdf_t {
 	 * section 4.4.4. Space for returned secret is allocated and must be freed
 	 * by the caller.
 	 *
-	 * @param is_server			TRUE if server, FALSE if client derives secret
+	 * @param server			Whether the client or server finish key is derived
 	 * @param finished			key will be written into this chunk
 	 * @return					TRUE if secrets derived successfully
 	 */
-	bool (*derive_finished)(tls_hkdf_t *this, bool is_server,
+	bool (*derive_finished)(tls_hkdf_t *this, bool server,
 							chunk_t *finished);
 
 	/**