Implemented an option to restict access to only known players.

src/defaultsettings.cpp

@@ -124,6 +124,7 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("max_users", "20");
 	settings->setDefault("strict_protocol_version_checking", "false");
 	settings->setDefault("disallow_empty_passwords","false");
+	settings->setDefault("disallow_unknown_users","false");
 	settings->setDefault("fixed_map_seed", "");
 	settings->setDefault("default_password", "");
 	settings->setDefault("default_privs", "build, shout");

src/server.cpp

@@ -1856,6 +1856,14 @@ void Server::ProcessData(u8 *data, u32 datasize, u16 peer_id)
 			SendAccessDenied(m_con, peer_id, L"Empty passwords are not allowed on this server.");
 			return;
 		}
+		
+		if (g_settings->getBool("disallow_unknown_users") &&
+ 			!m_authmanager.exists(playername)) {
+			infostream<<"Server: unknown player "<<playername
+				<<" was blocked"<<std::endl;
+			SendAccessDenied(m_con, peer_id, L"No unkown players allowed.");
+			return;
+		}
 
 		std::string checkpwd;
 		if (m_authmanager.exists(playername)) {

voxelands.conf.example

@@ -212,6 +212,8 @@
 #default_password =
 # Don't let players join with an empty password
 #disallow_empty_passwords = false
+# Don't let players join without a entry on the auth.txt (should be used with disallow_empty_passwords = true)
+#disallow_unknown_users = false
 # Available privileges: build, teleport, settime, privs, shout
 #default_privs = build, shout
 # enable a static spawnpoint (default unset)