mud/lib/secure/daemon/i3router/read_callback.h
2020-09-06 05:43:07 -07:00

285 lines
11 KiB
C

string *blacklisted_muds = ({});
static string *graylisted_muds = ({});
static mapping packet_counter = ([]);
void setup_blacklist(){
if(file_exists(ROUTER_BLACKLIST)){
blacklisted_muds += read_big_file(ROUTER_BLACKLIST);
blacklisted_muds = singular_array(blacklisted_muds);
//tc(identify(sizeof(blacklisted_muds)),"red");
}
}
void read_callback(mixed fd, mixed info){
mixed tmp;
// 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;
string *logspam = ({ "auth-mud-req", "auth-mud-reply", "tell", "emoteto",
"ping","channel-listen", "ping-req", "ping-reply" });
string ip_addr = (stringp(fd) ? fd : clean_fd(socket_address(fd)));
if(!packet_counter) packet_counter = ([]);
if(!strsrch(info[0],"irn-")){
irn_read_callback(fd, info);
return;
}
if(info[4] && !grepp(info[0],"startup-req") &&
member_array(info[4], keys(connected_muds)) == -1 &&
member_array(info[2], keys(connected_muds)) == -1){
return;
}
validate();
if(sizeof(blacklisted_muds)){
if(member_array(info[2], blacklisted_muds) != -1) return;
if(intp(fd)){
if(member_array(ip_addr, blacklisted_muds) != -1) return;
foreach(string bmud in blacklisted_muds){
if(sscanf(bmud, "%*d.%*s") && !strsrch(ip_addr, bmud)){
return;
}
}
}
}
if(!packet_counter[info[2]]){
packet_counter[info[2]] = ([ "time" : time(), "count" : 0 ]);
}
if(packet_counter[info[2]]["time"] != time()){
packet_counter[info[2]]["count"] = 0;
packet_counter[info[2]]["time"] = time();
}
if(info[0] != "channel-listen"){
if(!strsrch(info[0], "startup-req")){
packet_counter[info[2]]["count"] += 6;
}
else packet_counter[info[2]]["count"]++;
}
if(sizeof(graylisted_muds)){
if((info[2] && member_array(info[2], graylisted_muds) != -1) ||
(intp(fd) && member_array(ip_addr, graylisted_muds) != -1)){
if(info[2] && member_array(info[2], keys(connected_muds)) != -1){
if(packet_counter[info[2]]["count"] < 2){
send_error(info[2],info[3],"not-allowed",
"Your packets are being temporarily dropped "+
"due to flooding.", info);
}
}
return;
}
}
if(packet_counter[info[2]]["count"] > 10 &&
member_array(fd, keys(ROUTER_D->query_irn_sockets())) == -1){
if(info[2] && member_array(info[2], keys(connected_muds)) != -1){
send_error(info[2],info[3],"not-allowed",
"Flood detected! Your packets will be temporarily ignored.",
info);
}
graylisted_muds += ({ info[2] });
trr("Graylisting "+identify(info[2])+" from "+ip_addr,"red");
return;
}
if(member_array(info[0],logspam) == -1 && strsrch(info[0],"irn-")){
string foo = "IRN";
if(intp(fd)) foo = socket_address(fd);
trr(timestamp()+" Received from fd("+fd+"), source: "+foo+"\n"+identify(info), "green");
}
// Base info in a packet is of size 6.
// comment out the statements below to avoid a big channel log file
if(grepp(info[0],"chan") && !grepp(info[0],"channel-listen"))
server_log(identify(info),"chan_log");
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 && !mudinfo[info[4]] && info[4]!=router_name){
// if target mud is not 0 (broadcasting), not the router name,
// and not a known MUD
write_data(fd,({
"error",
5,
router_name,
0,
info[2],
info[3],
"unk-dst", // same as I3
"destination unknown", // same as I3
info
}));
trr("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...
trr("calling process_startup_req, i="+i+", fd="+fd+" which is: "+socket_address(fd));
//call_other(this_object(),"process_startup_req",i,info,fd);
this_object()->process_startup_req(i,info,fd);
return;
}
if(intp(fd) && !undefinedp(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
}));
server_log("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
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"}))==-1){
// 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...
if(intp(fd)) this_object()->SendMessage(info);
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...
if(intp(fd)) {
this_object()->SendMessage(info);
}
broadcast_data(connected_muds,info);
return;
}
if(info[4]==router_name) {
switch(info[0]){
case "shutdown" :
if(sizeof(info) != 7){
send_error(info[2],info[3],"bad-pkt","Wrong number of elements for packet: "+info[0],info);
return;
}
if(info[6] > 604800) {
server_log("ROUTER_D: deleting "+this_object()->query_connected_fds()[fd]+" per "+
"request of "+info[2]+"\n");
remove_mud(this_object()->query_connected_fds()[fd], 1);
}
else {
server_log("ROUTER_D: disconnecting "+this_object()->query_connected_fds()[fd]+" per "+
"request of "+info[2]);
this_object()->disconnect_mud(this_object()->query_connected_fds()[fd]);
}
break;
case "chanlist-req" : case "chanlist-request" :
broadcast_chanlist("foo",info[2]);
break;
default :
// 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);
server_log("%^RED%^UNHANDLED PACKET:\n"+identify(info));
}
return;
}
if(info[0]=="startup-reply" || info[0]=="chan-filter-reply"||
info[0]=="chanlist-reply" || info[0]=="mudlist" ||
info[0]=="bad-mojo"){
// Thanks to Tricky for pointing out the need for this safeguard
send_error(info[2],info[3],"not-allowed",
"You are not allowed to send this kind of packet.",info);
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;
}
}
// if fd is an integer (meaning it's locally connected) and info[4] is zero
// (meaning it's a boradcast) then we send data to irn. Also, if fd is an
// integer, info[4] is non-zero, and info[4] is not a connected mud.
if((!info[4] && intp(fd)) ||
(intp(fd) && info[4] && undefinedp(connected_muds[info[4]])) ){
this_object()->SendMessage(info);
}
tmp = (this_object()->query_connected_muds()[info[4]] || -1);
if(tmp > -1){
write_data(connected_muds[info[4]], info);
}
return;
}