// This file written completely by Tim Johnson (Tim@TimMUD) static void read_callback(int fd, mixed info){ // This is called when messages come in from a MUD. // Should reject all messages if they have not done a (successful) startup-req, // Should check to make sure the fd matches with the mud they are claiming to be, else error. // because all packets require an originator_mudname. // If target is the name of the router, then call the function in this object. // if target is 0, then broadcast to muds. // Do an error if target mudname is not known. // // According to: http://www.intermud.org/i3/specs/formats.php3 // Transmissions are LPC arrays with a predefined set of six initial elements: // ({ type, ttl, originator mudname, originator username, target mudname, target username, ... }). // info[0]=type // info[1]=ttl // info[2]=originator mudname // info[3]=originator username // info[4]=target mudname // info[5]=target username string mudname; int i; debug("Received from fd("+fd+")\n"+dump_variable(info),DEB_IN); // Base info in a packet is of size 6. if(sizeof(info)<6 || !stringp(info[0]) || !intp(info[1]) || !stringp(info[2]) || (!stringp(info[3]) && info[3]!=0) || (!stringp(info[4]) && info[4]!=0) || (!stringp(info[5]) && info[5]!=0) ) { write_data(fd,({ // okay, their initial data isn't fully there... // careful about array out of bounds... "error",5,router_name,0, (sizeof(info)>=3 ? info[2] : 0), // mud name (sizeof(info)>=4 ? info[3] : 0), // user name "bad-pkt","Invalid initial data",info })); return; } if(info[4]!=0 && !connected_muds[info[4]] && info[4]!=router_name){ // if target mud is not 0 (broadcasting), not the router name, // and not a connected MUD write_data(fd,({ "error", 5, router_name, 0, info[2], info[3], "unk-dst", // same as I3 "destination unknown", // same as I3 info })); debug("Error [unk-dst], because target is "+info[4]+" and thus invalid."); return; } if(sscanf(info[0],"startup-req-%d",i)==1){ // special condition for startup-req... debug("calling process_startup_req, i="+i+", fd="+fd); call_other(this_object(),"process_startup_req",i,info,fd); return; } if(!connected_muds[info[2]] || (connected_muds[info[2]]!=fd)){ // MUD hasn't done a startup-req yet write_data(fd,({ "error", 5, router_name, 0, // originator username info[2], // mud name info[3], // user name "unk-src", // error code "Your MUD hasn't registered as "+info[2]+" yet", // Error message info })); debug("They have not done a startup-req for fd="+fd+", mudname="+info[2]); return; } // at this point, I guess it has a valid origin and stuff if(sscanf(info[0],"channel-%*s")==1){ // command has a "channel-" prefix // special case for channel stuff debug("calling process_channel..."); process_channel(fd,info); return; } if(info[0]=="chan-filter-reply"){ if(!stringp(info[6]) || sizeof(info[7])<9 ){ // avoid out-of-bounds send_error(info[2],info[3],"bad-pkt", "Invalid chan-filter-reply packet.",info); } if(channels[info[6]][1]!=info[2]){ send_error(info[2],info[3],"not-allowed", "You are not the owner of "+info[6],info); return; } if(member_array(info[7][6],({ "channel-a", "channel-e", "channel-t"}))==-11){ // Not a valid channel packet. send_error(info[2],info[3],"not-allowed","*giggles*",info); } if(info[6]!=info[7][6]){ // They're trying to trick me into broadcasting // fake messages on another channel! // That's pretty funny :P // I'll have to remember to check if the official router falls for it. send_error(info[2],info[3],"not-allowed","Hehe!",info); return; } if(member_array(info[7][6],({ "channel-a", "channel-e", "channel-t"}))){ } // Broadcast the message... foreach(mudname in keys(connected_muds)){ if(member_array(mudname, listening[info[6]])!=-1) write_data(connected_muds[mudname],info[7]); } return; } if(info[4]==0){ // if broadcasting this... broadcast_data(connected_muds,info); return; } if(info[4]==router_name) { // Something meant for the router but not handled by now! send_error(info[2],info[3],"not-imp","Unknown command sent to router: "+info[0],info); debug("unhandled command meant for router: "+info[0]); log_file("server","UNHANDLED PACKET:\n"+dump_variable(info)+"\n"); return; } // at this point, I guess you should forward it to the destination... if(info[0]=="locate-reply"){ // Special case for locate-reply, because protocol 3 has a larger packet... if(sizeof(info)==8 && mudinfo[info[4]]["protocol"]>2){ // originator mud is sending a protocol 1/2 response, // but target understands 3, so add the extra info write_data(connected_muds[info[4]], ({ info[0],info[1],info[2],info[3],info[4],info[5], info[6],info[7],0,0 })); return; } if(sizeof(info)==10 && mudinfo[info[4]]["protocol"]<=2){ // target mud is being sent a protocol 3 response, // but only understands 1 & 2, so strip the extra info write_data(connected_muds[info[4]], ({ info[0],info[1],info[2],info[3],info[4],info[5], info[6],info[7] })); return; } } write_data(connected_muds[info[4]], info); return; }