void TreeSocket::ProcessConnectedLine(std::string& prefix, std::string& command, parameterlist& params)
{
User* who = ServerInstance->FindUUID(prefix);
std::string direction;
if (!who)
{
TreeServer* ServerSource = Utils->FindServer(prefix);
if (prefix.empty())
ServerSource = MyRoot;
if (ServerSource)
{
who = ServerSource->ServerUser;
}
else
{
/* It is important that we don't close the link here, unknown prefix can occur
* due to various race conditions such as the KILL message for a user somehow
* crossing the users QUIT further upstream from the server. Thanks jilles!
*/
if ((prefix.length() == UIDGenerator::UUID_LENGTH) && (isdigit(prefix[0])) &&
((command == "FMODE") || (command == "MODE") || (command == "KICK") || (command == "TOPIC") || (command == "KILL") || (command == "ADDLINE") || (command == "DELLINE")))
{
/* Special case, we cannot drop these commands as they've been committed already on a
* part of the network by the time we receive them, so in this scenario pretend the
* command came from a server to avoid desync.
*/
who = ServerInstance->FindUUID(prefix.substr(0, 3));
if (!who)
who = this->MyRoot->ServerUser;
}
else
{
ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Command '%s' from unknown prefix '%s'! Dropping entire command.",
command.c_str(), prefix.c_str());
return;
}
}
}
// Make sure prefix is still good
direction = who->server;
prefix = who->uuid;
/*
* Check for fake direction here, and drop any instances that are found.
* What is fake direction? Imagine the following server setup:
* 0AA <-> 0AB <-> 0AC
* Fake direction would be 0AC sending a message to 0AB claiming to be from
* 0AA, or something similar. Basically, a message taking a path that *cannot*
* be correct.
*
* When would this be seen?
* Well, hopefully never. It could be caused by race conditions, bugs, or
* "miscreant" servers, though, so let's check anyway. -- w
*
* We also check here for totally invalid prefixes (prefixes that are neither
* a valid SID or a valid UUID, so that invalid UUID or SID never makes it
* to the higher level functions. -- B
*/
TreeServer* route_back_again = Utils->BestRouteTo(direction);
if ((!route_back_again) || (route_back_again->GetSocket() != this))
{
if (route_back_again)
ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Protocol violation: Fake direction '%s' from connection '%s'",
prefix.c_str(),linkID.c_str());
return;
}
// Translate commands coming from servers using an older protocol
if (proto_version < ProtocolVersion)
{
if (!PreProcessOldProtocolMessage(who, command, params))
return;
}
ServerCommand* scmd = Utils->Creator->CmdManager.GetHandler(command);
CommandBase* cmdbase = scmd;
Command* cmd;
if (!scmd)
{
// Not a special server-to-server command
cmd = ServerInstance->Parser->GetHandler(command);
if (!cmd)
{
irc::stringjoiner pmlist(params);
ServerInstance->Logs->Log(MODNAME, LOG_SPARSE, "Unrecognised S2S command :%s %s %s",
who->uuid.c_str(), command.c_str(), pmlist.GetJoined().c_str());
SendError("Unrecognised command '" + command + "' -- possibly loaded mismatched modules");
return;
}
cmdbase = cmd;
}
if (params.size() < cmdbase->min_params)
{
irc::stringjoiner pmlist(params);
ServerInstance->Logs->Log(MODNAME, LOG_SPARSE, "Insufficient parameters for S2S command :%s %s %s",
who->uuid.c_str(), command.c_str(), pmlist.GetJoined().c_str());
SendError("Insufficient parameters for command '" + command + "'");
return;
}
if ((!params.empty()) && (params.back().empty()) && (!cmdbase->allow_empty_last_param))
{
// the last param is empty and the command handler doesn't allow that, check if there will be enough params if we drop the last
if (params.size()-1 < cmdbase->min_params)
return;
params.pop_back();
}
CmdResult res;
if (scmd)
res = scmd->Handle(who, params);
else
res = cmd->Handle(params, who);
if (res == CMD_INVALID)
{
irc::stringjoiner pmlist(params);
ServerInstance->Logs->Log(MODNAME, LOG_SPARSE, "Error handling S2S command :%s %s %s",
who->uuid.c_str(), command.c_str(), pmlist.GetJoined().c_str());
SendError("Error handling '" + command + "' -- possibly loaded mismatched modules");
}
else if (res == CMD_SUCCESS)
Utils->RouteCommand(route_back_again, cmdbase, params, who);
}
void TreeSocket::ProcessConnectedLine(std::string& prefix, std::string& command, parameterlist& params)
{
User* who = FindSource(prefix, command);
if (!who)
{
ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Command '%s' from unknown prefix '%s'! Dropping entire command.", command.c_str(), prefix.c_str());
return;
}
/*
* Check for fake direction here, and drop any instances that are found.
* What is fake direction? Imagine the following server setup:
* 0AA <-> 0AB <-> 0AC
* Fake direction would be 0AC sending a message to 0AB claiming to be from
* 0AA, or something similar. Basically, a message taking a path that *cannot*
* be correct.
*
* When would this be seen?
* Well, hopefully never. It could be caused by race conditions, bugs, or
* "miscreant" servers, though, so let's check anyway. -- w
*
* We also check here for totally invalid prefixes (prefixes that are neither
* a valid SID or a valid UUID, so that invalid UUID or SID never makes it
* to the higher level functions. -- B
*/
TreeServer* const server = TreeServer::Get(who);
if (server->GetSocket() != this)
{
ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Protocol violation: Fake direction '%s' from connection '%s'", prefix.c_str(), linkID.c_str());
return;
}
// Translate commands coming from servers using an older protocol
if (proto_version < ProtocolVersion)
{
if (!PreProcessOldProtocolMessage(who, command, params))
return;
}
ServerCommand* scmd = Utils->Creator->CmdManager.GetHandler(command);
CommandBase* cmdbase = scmd;
Command* cmd = NULL;
if (!scmd)
{
// Not a special server-to-server command
cmd = ServerInstance->Parser.GetHandler(command);
if (!cmd)
{
if (command == "ERROR")
{
this->Error(params);
return;
}
throw ProtocolException("Unknown command");
}
cmdbase = cmd;
}
if (params.size() < cmdbase->min_params)
throw ProtocolException("Insufficient parameters");
if ((!params.empty()) && (params.back().empty()) && (!cmdbase->allow_empty_last_param))
{
// the last param is empty and the command handler doesn't allow that, check if there will be enough params if we drop the last
if (params.size()-1 < cmdbase->min_params)
return;
params.pop_back();
}
CmdResult res;
if (scmd)
res = scmd->Handle(who, params);
else
{
res = cmd->Handle(params, who);
if (res == CMD_INVALID)
throw ProtocolException("Error in command handler");
}
if (res == CMD_SUCCESS)
Utils->RouteCommand(server->GetRoute(), cmdbase, params, who);
}
