/*
===========================================================================

Return to Castle Wolfenstein single player GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Return to Castle Wolfenstein single player GPL Source Code (RTCW SP Source Code).  

RTCW SP Source Code is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

RTCW SP Source Code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with RTCW SP Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the RTCW SP Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the RTCW SP Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/


#include "server.h"

#ifdef USE_VOIP
cvar_t *sv_voip;
cvar_t *sv_voipProtocol;
#endif

serverStatic_t svs;                 // persistant server info
server_t sv;                        // local server
vm_t            *gvm = NULL;                // game virtual machine

cvar_t  *sv_fps = NULL;		// time rate for running non-clients
cvar_t  *sv_timeout;            // seconds without any message
cvar_t  *sv_zombietime;         // seconds to sink messages after disconnect
cvar_t  *sv_rconPassword;       // password for remote server commands
cvar_t  *sv_privatePassword;    // password for the privateClient slots
cvar_t  *sv_allowDownload;
cvar_t  *sv_maxclients;
cvar_t  *sv_privateClients;     // number of clients reserved for password
cvar_t  *sv_hostname;
cvar_t  *sv_master[MAX_MASTER_SERVERS];     // master server ip address
cvar_t  *sv_reconnectlimit;     // minimum seconds between connect messages
cvar_t  *sv_showloss;           // report when usercmds are lost
cvar_t  *sv_padPackets;         // add nop bytes to messages
cvar_t  *sv_killserver;         // menu system can set to 1 to shut server down
cvar_t  *sv_mapname;
cvar_t  *sv_mapChecksum;
cvar_t  *sv_serverid;
cvar_t	*sv_minRate;
cvar_t  *sv_maxRate;
cvar_t	*sv_dlRate;
cvar_t  *sv_minPing;
cvar_t  *sv_maxPing;
cvar_t  *sv_gametype;
cvar_t  *sv_pure;
cvar_t  *sv_floodProtect;
cvar_t	*sv_lanForceRate; // dedicated 1 (LAN) server forces local client rates to 99999 (bug #491)
cvar_t  *sv_allowAnonymous;

cvar_t	*sv_banFile;

serverBan_t serverBans[SERVER_MAXBANS];
int serverBansCount = 0;

// Rafael gameskill
cvar_t  *sv_gameskill;
// done

cvar_t  *sv_reloading;  //----(SA)	added

/*
=============================================================================

EVENT MESSAGES

=============================================================================
*/

/*
===============
SV_ExpandNewlines

Converts newlines to "\n" so a line prints nicer
===============
*/
static char	*SV_ExpandNewlines( char *in ) {
	static char string[1024];
	int l;

	l = 0;
	while ( *in && l < sizeof( string ) - 3 ) {
		if ( *in == '\n' ) {
			string[l++] = '\\';
			string[l++] = 'n';
		} else {
			string[l++] = *in;
		}
		in++;
	}
	string[l] = 0;

	return string;
}

/*
======================
SV_ReplacePendingServerCommands

FIXME: This is ugly
======================
*/
#if 0   // RF, not used anymore
static int SV_ReplacePendingServerCommands( client_t *client, const char *cmd ) {
	int i, index, csnum1, csnum2;

	for ( i = client->reliableSent + 1; i <= client->reliableSequence; i++ ) {
		index = i & ( MAX_RELIABLE_COMMANDS - 1 );
		//
		//if ( !Q_strncmp(cmd, client->reliableCommands[ index ], strlen("cs")) ) {
		if ( !Q_strncmp( cmd, SV_GetReliableCommand( client, index ), strlen( "cs" ) ) ) {
			sscanf( cmd, "cs %i", &csnum1 );
			//sscanf(client->reliableCommands[ index ], "cs %i", &csnum2);
			sscanf( SV_GetReliableCommand( client, index ), "cs %i", &csnum2 );
			if ( csnum1 == csnum2 ) {
				//Q_strncpyz( client->reliableCommands[ index ], cmd, sizeof( client->reliableCommands[ index ] ) );

				/*
				if ( client->netchan.remoteAddress.type != NA_BOT ) {
					Com_Printf( "WARNING: client %i removed double pending config string %i: %s\n", client-svs.clients, csnum1, cmd );
				}
				*/
				return qtrue;
			}
		}
	}
	return qfalse;
}
#endif

/*
======================
SV_AddServerCommand

The given command will be transmitted to the client, and is guaranteed to
not have future snapshot_t executed before it is executed
======================
*/
void SV_AddServerCommand( client_t *client, const char *cmd ) {
	int index, i;

	// do not send commands until the gamestate has been sent
	if( client->state < CS_PRIMED )
		return;

	client->reliableSequence++;
	// if we would be losing an old command that hasn't been acknowledged,
	// we must drop the connection
	// we check == instead of >= so a broadcast print added by SV_DropClient()
	// doesn't cause a recursive drop client
	if ( client->reliableSequence - client->reliableAcknowledge == MAX_RELIABLE_COMMANDS + 1 ) {
		Com_Printf( "===== pending server commands =====\n" );
		for ( i = client->reliableAcknowledge + 1 ; i <= client->reliableSequence ; i++ ) {
			//Com_Printf( "cmd %5d: %s\n", i, client->reliableCommands[ i & (MAX_RELIABLE_COMMANDS-1) ] );
			Com_Printf( "cmd %5d: %s\n", i, SV_GetReliableCommand( client, i & ( MAX_RELIABLE_COMMANDS - 1 ) ) );
		}
		Com_Printf( "cmd %5d: %s\n", i, cmd );
		SV_DropClient( client, "Server command overflow" );
		return;
	}
	index = client->reliableSequence & ( MAX_RELIABLE_COMMANDS - 1 );
	//Q_strncpyz( client->reliableCommands[ index ], cmd, sizeof( client->reliableCommands[ index ] ) );
	SV_AddReliableCommand( client, index, cmd );
}


/*
=================
SV_SendServerCommand

Sends a reliable command string to be interpreted by
the client game module: "cp", "print", "chat", etc
A NULL client will broadcast to all clients
=================
*/
void QDECL SV_SendServerCommand( client_t *cl, const char *fmt, ... ) {
	va_list argptr;
	byte message[MAX_MSGLEN];
	client_t    *client;
	int j;

	va_start( argptr,fmt );
	Q_vsnprintf ((char *)message, sizeof(message), fmt,argptr);
	va_end( argptr );

	// Fix to http://aluigi.altervista.org/adv/q3msgboom-adv.txt
	// The actual cause of the bug is probably further downstream
	// and should maybe be addressed later, but this certainly
	// fixes the problem for now
	if ( strlen ((char *)message) > 1022 ) {
		return;
	}

	if ( cl != NULL ) {
		SV_AddServerCommand( cl, (char *)message );
		return;
	}

	// hack to echo broadcast prints to console
	if ( com_dedicated->integer && !strncmp( (char *)message, "print", 5 ) ) {
		Com_Printf( "broadcast: %s\n", SV_ExpandNewlines( (char *)message ) );
	}

	// send the data to all relevent clients
	for ( j = 0, client = svs.clients; j < sv_maxclients->integer ; j++, client++ ) {
		// Ridah, don't need to send messages to AI
		if ( client->gentity && client->gentity->r.svFlags & SVF_CASTAI ) {
			continue;
		}
		// done.
		SV_AddServerCommand( client, (char *)message );
	}
}


/*
==============================================================================

MASTER SERVER FUNCTIONS

==============================================================================
*/

/*
================
SV_MasterHeartbeat

Send a message to the masters every few minutes to
let it know we are alive, and log information.
We will also have a heartbeat sent when a server
changes from empty to non-empty, and full to non-full,
but not on every player enter or exit.
================
*/
#define HEARTBEAT_MSEC  300 * 1000
void SV_MasterHeartbeat(const char *message)
{
	static netadr_t	adr[MAX_MASTER_SERVERS][2]; // [2] for v4 and v6 address for the same address string.
	int i;
	int			res;
	int			netenabled;

	netenabled = Cvar_VariableIntegerValue("net_enabled");

	// "dedicated 1" is for lan play, "dedicated 2" is for inet public play
	if (!com_dedicated || com_dedicated->integer != 2 || !(netenabled & (NET_ENABLEV4 | NET_ENABLEV6)))
		return;     // only dedicated servers send heartbeats

	// if not time yet, don't send anything
	if ( svs.time < svs.nextHeartbeatTime )
		return;

	if ( !Q_stricmp( com_gamename->string, LEGACY_MASTER_GAMENAME ) )
		message = LEGACY_HEARTBEAT_FOR_MASTER;

	svs.nextHeartbeatTime = svs.time + HEARTBEAT_MSEC;

	// send to group masters
	for (i = 0; i < MAX_MASTER_SERVERS; i++)
	{
		if(!sv_master[i]->string[0])
			continue;

		// see if we haven't already resolved the name
		// resolving usually causes hitches on win95, so only
		// do it when needed
		if(sv_master[i]->modified || (adr[i][0].type == NA_BAD && adr[i][1].type == NA_BAD))
		{
			sv_master[i]->modified = qfalse;

			if(netenabled & NET_ENABLEV4)
			{
				Com_Printf("Resolving %s (IPv4)\n", sv_master[i]->string);
				res = NET_StringToAdr(sv_master[i]->string, &adr[i][0], NA_IP);

				if(res == 2)
				{
					// if no port was specified, use the default master port
					adr[i][0].port = BigShort(PORT_MASTER);
				}
				
				if(res)
					Com_Printf( "%s resolved to %s\n", sv_master[i]->string, NET_AdrToStringwPort(adr[i][0]));
				else
					Com_Printf( "%s has no IPv4 address.\n", sv_master[i]->string);
			}
			
			if(netenabled & NET_ENABLEV6)
			{
				Com_Printf("Resolving %s (IPv6)\n", sv_master[i]->string);
				res = NET_StringToAdr(sv_master[i]->string, &adr[i][1], NA_IP6);

				if(res == 2)
				{
					// if no port was specified, use the default master port
					adr[i][1].port = BigShort(PORT_MASTER);
				}
				
				if(res)
					Com_Printf( "%s resolved to %s\n", sv_master[i]->string, NET_AdrToStringwPort(adr[i][1]));
				else
					Com_Printf( "%s has no IPv6 address.\n", sv_master[i]->string);
			}

			if(adr[i][0].type == NA_BAD && adr[i][1].type == NA_BAD)
			{

				// if the address failed to resolve, clear it
				// so we don't take repeated dns hits
				Com_Printf("Couldn't resolve address: %s\n", sv_master[i]->string);
				Cvar_Set(sv_master[i]->name, "");
				sv_master[i]->modified = qfalse;
				continue;
			}
		}


		Com_Printf( "Sending heartbeat to %s\n", sv_master[i]->string );
		// this command should be changed if the server info / status format
		// ever incompatably changes
		if(adr[i][0].type != NA_BAD)
			NET_OutOfBandPrint( NS_SERVER, adr[i][0], "heartbeat %s\n", message);
		if(adr[i][1].type != NA_BAD)
			NET_OutOfBandPrint( NS_SERVER, adr[i][1], "heartbeat %s\n", message);
	}
}

/*
=================
SV_MasterShutdown

Informs all masters that this server is going down
=================
*/
void SV_MasterShutdown( void ) {
	// send a heartbeat right now
	svs.nextHeartbeatTime = -9999;
	SV_MasterHeartbeat(FLATLINE_FOR_MASTER);

	// send it again to minimize chance of drops
	svs.nextHeartbeatTime = -9999;
	SV_MasterHeartbeat(FLATLINE_FOR_MASTER);

	// when the master tries to poll the server, it won't respond, so
	// it will be removed from the list
}

/*
==============================================================================

CONNECTIONLESS COMMANDS

==============================================================================
*/

// This is deliberately quite large to make it more of an effort to DoS
#define MAX_BUCKETS			16384
#define MAX_HASHES			1024

static leakyBucket_t buckets[ MAX_BUCKETS ];
static leakyBucket_t *bucketHashes[ MAX_HASHES ];
leakyBucket_t outboundLeakyBucket;

/*
================
SVC_HashForAddress
================
*/
static long SVC_HashForAddress( netadr_t address ) {
	byte 		*ip = NULL;
	size_t	size = 0;
	int			i;
	long		hash = 0;

	switch ( address.type ) {
		case NA_IP:  ip = address.ip;  size = 4; break;
		case NA_IP6: ip = address.ip6; size = 16; break;
		default: break;
	}

	for ( i = 0; i < size; i++ ) {
		hash += (long)( ip[ i ] ) * ( i + 119 );
	}

	hash = ( hash ^ ( hash >> 10 ) ^ ( hash >> 20 ) );
	hash &= ( MAX_HASHES - 1 );

	return hash;
}

/*
================
SVC_BucketForAddress

Find or allocate a bucket for an address
================
*/
static leakyBucket_t *SVC_BucketForAddress( netadr_t address, int burst, int period ) {
	leakyBucket_t	*bucket = NULL;
	int						i;
	long					hash = SVC_HashForAddress( address );
	int						now = Sys_Milliseconds();

	for ( bucket = bucketHashes[ hash ]; bucket; bucket = bucket->next ) {
		switch ( bucket->type ) {
			case NA_IP:
				if ( memcmp( bucket->ipv._4, address.ip, 4 ) == 0 ) {
					return bucket;
				}
				break;

			case NA_IP6:
				if ( memcmp( bucket->ipv._6, address.ip6, 16 ) == 0 ) {
					return bucket;
				}
				break;

			default:
				break;
		}
	}

	for ( i = 0; i < MAX_BUCKETS; i++ ) {
		int interval;

		bucket = &buckets[ i ];
		interval = now - bucket->lastTime;

		// Reclaim expired buckets
		if ( bucket->lastTime > 0 && ( interval > ( burst * period ) ||
					interval < 0 ) ) {
			if ( bucket->prev != NULL ) {
				bucket->prev->next = bucket->next;
			} else {
				bucketHashes[ bucket->hash ] = bucket->next;
			}
			
			if ( bucket->next != NULL ) {
				bucket->next->prev = bucket->prev;
			}

			Com_Memset( bucket, 0, sizeof( leakyBucket_t ) );
		}

		if ( bucket->type == NA_BAD ) {
			bucket->type = address.type;
			switch ( address.type ) {
				case NA_IP:  Com_Memcpy( bucket->ipv._4, address.ip, 4 );   break;
				case NA_IP6: Com_Memcpy( bucket->ipv._6, address.ip6, 16 ); break;
				default: break;
			}

			bucket->lastTime = now;
			bucket->burst = 0;
			bucket->hash = hash;

			// Add to the head of the relevant hash chain
			bucket->next = bucketHashes[ hash ];
			if ( bucketHashes[ hash ] != NULL ) {
				bucketHashes[ hash ]->prev = bucket;
			}

			bucket->prev = NULL;
			bucketHashes[ hash ] = bucket;

			return bucket;
		}
	}

	// Couldn't allocate a bucket for this address
	return NULL;
}

/*
================
SVC_RateLimit
================
*/
qboolean SVC_RateLimit( leakyBucket_t *bucket, int burst, int period ) {
	if ( bucket != NULL ) {
		int now = Sys_Milliseconds();
		int interval = now - bucket->lastTime;
		int expired = interval / period;
		int expiredRemainder = interval % period;

		if ( expired > bucket->burst || interval < 0 ) {
			bucket->burst = 0;
			bucket->lastTime = now;
		} else {
			bucket->burst -= expired;
			bucket->lastTime = now - expiredRemainder;
		}

		if ( bucket->burst < burst ) {
			bucket->burst++;

			return qfalse;
		}
	}

	return qtrue;
}

/*
================
SVC_RateLimitAddress

Rate limit for a particular address
================
*/
qboolean SVC_RateLimitAddress( netadr_t from, int burst, int period ) {
	leakyBucket_t *bucket = SVC_BucketForAddress( from, burst, period );

	return SVC_RateLimit( bucket, burst, period );
}

/*
================
SVC_Status

Responds with all the info that qplug or qspy can see about the server
and all connected players.  Used for getting detailed information after
the simple info query.
================
*/
static void SVC_Status( netadr_t from ) {
	char player[1024];
	char status[MAX_MSGLEN];
	int i;
	client_t    *cl;
	playerState_t   *ps;
	int statusLength;
	int playerLength;
	char infostring[MAX_INFO_STRING];

	// ignore if we are in single player
	if ( Cvar_VariableValue( "g_gametype" ) == GT_SINGLE_PLAYER || Cvar_VariableValue("ui_singlePlayerActive")) {
		return;
	}

	// Prevent using getstatus as an amplifier
	if ( SVC_RateLimitAddress( from, 10, 1000 ) ) {
		Com_DPrintf( "SVC_Status: rate limit from %s exceeded, dropping request\n",
			NET_AdrToString( from ) );
		return;
	}

	// Allow getstatus to be DoSed relatively easily, but prevent
	// excess outbound bandwidth usage when being flooded inbound
	if ( SVC_RateLimit( &outboundLeakyBucket, 10, 100 ) ) {
		Com_DPrintf( "SVC_Status: rate limit exceeded, dropping request\n" );
		return;
	}

	// A maximum challenge length of 128 should be more than plenty.
	if(strlen(Cmd_Argv(1)) > 128)
		return;

	strcpy( infostring, Cvar_InfoString( CVAR_SERVERINFO ) );

	// echo back the parameter to status. so master servers can use it as a challenge
	// to prevent timed spoofed reply packets that add ghost servers
	Info_SetValueForKey( infostring, "challenge", Cmd_Argv( 1 ) );

	status[0] = 0;
	statusLength = 0;

	for ( i = 0 ; i < sv_maxclients->integer ; i++ ) {
		cl = &svs.clients[i];
		if ( cl->state >= CS_CONNECTED ) {
			ps = SV_GameClientNum( i );
			Com_sprintf( player, sizeof( player ), "%i %i \"%s\"\n",
						 ps->persistant[PERS_SCORE], cl->ping, cl->name );
			playerLength = strlen( player );
			if ( statusLength + playerLength >= sizeof( status ) ) {
				break;      // can't hold any more
			}
			strcpy( status + statusLength, player );
			statusLength += playerLength;
		}
	}

	NET_OutOfBandPrint( NS_SERVER, from, "statusResponse\n%s\n%s", infostring, status );
}

/*
================
SVC_Info

Responds with a short info message that should be enough to determine
if a user is interested in a server to do a full status
================
*/
void SVC_Info( netadr_t from ) {
	int		i, count, humans;
	char    *gamedir;
	char infostring[MAX_INFO_STRING];

	// ignore if we are in single player
	if ( Cvar_VariableValue( "g_gametype" ) == GT_SINGLE_PLAYER ) {
		return;
	}

	// Prevent using getinfo as an amplifier
	if ( SVC_RateLimitAddress( from, 10, 1000 ) ) {
		Com_DPrintf( "SVC_Info: rate limit from %s exceeded, dropping request\n",
			NET_AdrToString( from ) );
		return;
	}

	// Allow getinfo to be DoSed relatively easily, but prevent
	// excess outbound bandwidth usage when being flooded inbound
	if ( SVC_RateLimit( &outboundLeakyBucket, 10, 100 ) ) {
		Com_DPrintf( "SVC_Info: rate limit exceeded, dropping request\n" );
		return;
	}

	/*
	 * Check whether Cmd_Argv(1) has a sane length. This was not done in the original Quake3 version which led
	 * to the Infostring bug discovered by Luigi Auriemma. See http://aluigi.altervista.org/ for the advisory.
	 */

	// A maximum challenge length of 128 should be more than plenty.
	if(strlen(Cmd_Argv(1)) > 128)
		return;

	// don't count privateclients
	count = humans = 0;
	for ( i = sv_privateClients->integer ; i < sv_maxclients->integer ; i++ ) {
		if ( svs.clients[i].state >= CS_CONNECTED ) {
			count++;
			if (svs.clients[i].netchan.remoteAddress.type != NA_BOT) {
				humans++;
			}
		}
	}

	infostring[0] = 0;

	// echo back the parameter to status. so servers can use it as a challenge
	// to prevent timed spoofed reply packets that add ghost servers
	Info_SetValueForKey( infostring, "challenge", Cmd_Argv( 1 ) );

	Info_SetValueForKey( infostring, "gamename", com_gamename->string );

#ifdef LEGACY_PROTOCOL
	if(com_legacyprotocol->integer > 0)
		Info_SetValueForKey(infostring, "protocol", va("%i", com_legacyprotocol->integer));
	else
#endif
		Info_SetValueForKey(infostring, "protocol", va("%i", com_protocol->integer));

	Info_SetValueForKey( infostring, "hostname", sv_hostname->string );
	Info_SetValueForKey( infostring, "mapname", sv_mapname->string );
	Info_SetValueForKey( infostring, "clients", va( "%i", count ) );
	Info_SetValueForKey( infostring, "g_humanplayers", va( "%i", humans ) );
	Info_SetValueForKey( infostring, "sv_maxclients",
						 va( "%i", sv_maxclients->integer - sv_privateClients->integer ) );
	Info_SetValueForKey( infostring, "gametype", va( "%i", sv_gametype->integer ) );
	Info_SetValueForKey( infostring, "pure", va( "%i", sv_pure->integer ) );
	Info_SetValueForKey( infostring, "g_needpass", va( "%d", Cvar_VariableIntegerValue( "g_needpass" ) ) );

#ifdef USE_VOIP
	if (sv_voipProtocol->string && *sv_voipProtocol->string) {
		Info_SetValueForKey( infostring, "voip", sv_voipProtocol->string );
	}
#endif

	if ( sv_minPing->integer ) {
		Info_SetValueForKey( infostring, "minPing", va( "%i", sv_minPing->integer ) );
	}
	if ( sv_maxPing->integer ) {
		Info_SetValueForKey( infostring, "maxPing", va( "%i", sv_maxPing->integer ) );
	}
	gamedir = Cvar_VariableString( "fs_game" );
	if ( *gamedir ) {
		Info_SetValueForKey( infostring, "game", gamedir );
	}
	Info_SetValueForKey( infostring, "sv_allowAnonymous", va( "%i", sv_allowAnonymous->integer ) );

	// Rafael gameskill
	Info_SetValueForKey( infostring, "gameskill", va( "%i", sv_gameskill->integer ) );
	// done

	NET_OutOfBandPrint( NS_SERVER, from, "infoResponse\n%s", infostring );
}

/*
==============
SV_FlushRedirect

==============
*/
static void SV_FlushRedirect( char *outputbuf ) {
	NET_OutOfBandPrint( NS_SERVER, svs.redirectAddress, "print\n%s", outputbuf );
}

/*
===============
SVC_RemoteCommand

An rcon packet arrived from the network.
Shift down the remaining args
Redirect all printfs
===============
*/
static void SVC_RemoteCommand( netadr_t from, msg_t *msg ) {
	qboolean valid;
	char remaining[1024];
#define SV_OUTPUTBUF_LENGTH ( MAX_MSGLEN - 16 )
	char sv_outputbuf[SV_OUTPUTBUF_LENGTH];
	char *cmd_aux;

	if ( !strlen( sv_rconPassword->string ) ||
		 strcmp( Cmd_Argv( 1 ), sv_rconPassword->string ) ) {
		static leakyBucket_t bucket;

		// Make DoS via rcon impractical
		if ( SVC_RateLimit( &bucket, 10, 1000 ) ) {
			Com_DPrintf( "SVC_RemoteCommand: rate limit exceeded, dropping request\n" );
			return;
		}

		valid = qfalse;
		Com_DPrintf( "Bad rcon from %s:\n%s\n", NET_AdrToString( from ), Cmd_Argv( 2 ) );
	} else {
		valid = qtrue;
		Com_DPrintf( "Rcon from %s:\n%s\n", NET_AdrToString( from ), Cmd_Argv( 2 ) );
	}

	// start redirecting all print outputs to the packet
	svs.redirectAddress = from;
	Com_BeginRedirect( sv_outputbuf, SV_OUTPUTBUF_LENGTH, SV_FlushRedirect );

	// Prevent using rcon as an amplifier and make dictionary attacks impractical
	if ( SVC_RateLimitAddress( from, 10, 1000 ) ) {
		Com_DPrintf( "SVC_RemoteCommand: rate limit from %s exceeded, dropping request\n",
			NET_AdrToString( from ) );
 		return;
 	}

	if ( !strlen( sv_rconPassword->string ) ) {
		Com_Printf( "No rconpassword set.\n" );
	} else if ( !valid ) {
		Com_Printf( "Bad rconpassword.\n" );
	} else {
		remaining[0] = 0;

		// https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=543
		// get the command directly, "rcon <pass> <command>" to avoid quoting issues
		// extract the command by walking
		// since the cmd formatting can fuckup (amount of spaces), using a dumb step by step parsing
		cmd_aux = Cmd_Cmd();
		cmd_aux+=4;
		while(cmd_aux[0]==' ')
			cmd_aux++;
		while(cmd_aux[0] && cmd_aux[0]!=' ') // password
			cmd_aux++;
		while(cmd_aux[0]==' ')
			cmd_aux++;
		
		Q_strcat( remaining, sizeof(remaining), cmd_aux);
		
		Cmd_ExecuteString (remaining);

	}

	Com_EndRedirect();
}

/*
=================
SV_ConnectionlessPacket

A connectionless packet has four leading 0xff
characters to distinguish it from a game channel.
Clients that are in the game can still send
connectionless packets.
=================
*/
static void SV_ConnectionlessPacket( netadr_t from, msg_t *msg ) {
	char    *s;
	char    *c;

	MSG_BeginReadingOOB( msg );
	MSG_ReadLong( msg );        // skip the -1 marker

	if (!Q_strncmp("connect", (char *) &msg->data[4], 7)) {
		Huff_Decompress( msg, 12 );
	}	

	s = MSG_ReadStringLine( msg );

	Cmd_TokenizeString( s );

	c = Cmd_Argv( 0 );
	Com_DPrintf( "SV packet %s : %s\n", NET_AdrToString( from ), c );

	if ( !Q_stricmp( c,"getstatus" ) ) {
		SVC_Status( from );
	} else if ( !Q_stricmp( c,"getinfo" ) ) {
		SVC_Info( from );
	} else if ( !Q_stricmp( c,"getchallenge" ) ) {
		SV_GetChallenge( from );
	} else if ( !Q_stricmp( c,"connect" ) ) {
		SV_DirectConnect( from );
#ifndef STANDALONE
	} else if ( !Q_stricmp( c,"ipAuthorize" ) ) {
		SV_AuthorizeIpPacket( from );
#endif
	} else if ( !Q_stricmp( c, "rcon" ) ) {
		SVC_RemoteCommand( from, msg );
	} else if ( !Q_stricmp( c,"disconnect" ) ) {
		// if a client starts up a local server, we may see some spurious
		// server disconnect messages when their new server sees our final
		// sequenced messages to the old client
	} else {
		Com_DPrintf ("bad connectionless packet from %s:\n%s\n",
			NET_AdrToString (from), s);
	}
}


//============================================================================

/*
=================
SV_PacketEvent
=================
*/
void SV_PacketEvent( netadr_t from, msg_t *msg ) {
	int i;
	client_t    *cl;
	int qport;

	// check for connectionless packet (0xffffffff) first
	if ( msg->cursize >= 4 && *(int *)msg->data == -1 ) {
		SV_ConnectionlessPacket( from, msg );
		return;
	}

	// read the qport out of the message so we can fix up
	// stupid address translating routers
	MSG_BeginReadingOOB( msg );
	MSG_ReadLong( msg );                // sequence number
	qport = MSG_ReadShort( msg ) & 0xffff;

	// find which client the message is from
	for ( i = 0, cl = svs.clients ; i < sv_maxclients->integer ; i++,cl++ ) {
		if ( cl->state == CS_FREE ) {
			continue;
		}
		if ( !NET_CompareBaseAdr( from, cl->netchan.remoteAddress ) ) {
			continue;
		}
		// it is possible to have multiple clients from a single IP
		// address, so they are differentiated by the qport variable
		if ( cl->netchan.qport != qport ) {
			continue;
		}

		// the IP port can't be used to differentiate them, because
		// some address translating routers periodically change UDP
		// port assignments
		if ( cl->netchan.remoteAddress.port != from.port ) {
			Com_Printf( "SV_ReadPackets: fixing up a translated port\n" );
			cl->netchan.remoteAddress.port = from.port;
		}

		// make sure it is a valid, in sequence packet
		if ( SV_Netchan_Process( cl, msg ) ) {
			// zombie clients still need to do the Netchan_Process
			// to make sure they don't need to retransmit the final
			// reliable message, but they don't do any other processing
			if ( cl->state != CS_ZOMBIE ) {
				cl->lastPacketTime = svs.time;  // don't timeout
				SV_ExecuteClientMessage( cl, msg );
			}
		}
		return;
	}
}


/*
===================
SV_CalcPings

Updates the cl->ping variables
===================
*/
static void SV_CalcPings( void ) {
	int i, j;
	client_t    *cl;
	int total, count;
	int delta;
	playerState_t   *ps;

	for ( i = 0 ; i < sv_maxclients->integer ; i++ ) {
		cl = &svs.clients[i];
		if ( cl->state != CS_ACTIVE ) {
			cl->ping = 999;
			continue;
		}
		if ( !cl->gentity ) {
			cl->ping = 999;
			continue;
		}
		if ( cl->gentity->r.svFlags & SVF_BOT ) {
			cl->ping = 0;
			continue;
		}

		total = 0;
		count = 0;
		for ( j = 0 ; j < PACKET_BACKUP ; j++ ) {
			if ( cl->frames[j].messageAcked <= 0 ) {
				continue;
			}
			delta = cl->frames[j].messageAcked - cl->frames[j].messageSent;
			count++;
			total += delta;
		}
		if ( !count ) {
			cl->ping = 999;
		} else {
			cl->ping = total / count;
			if ( cl->ping > 999 ) {
				cl->ping = 999;
			}
		}

		// let the game dll know about the ping
		ps = SV_GameClientNum( i );
		ps->ping = cl->ping;
	}
}

/*
==================
SV_CheckTimeouts

If a packet has not been received from a client for timeout->integer
seconds, drop the conneciton.  Server time is used instead of
realtime to avoid dropping the local client while debugging.

When a client is normally dropped, the client_t goes into a zombie state
for a few seconds to make sure any final reliable message gets resent
if necessary
==================
*/
static void SV_CheckTimeouts( void ) {
	int i;
	client_t    *cl;
	int droppoint;
	int zombiepoint;

	droppoint = svs.time - 1000 * sv_timeout->integer;
	zombiepoint = svs.time - 1000 * sv_zombietime->integer;

	for ( i = 0,cl = svs.clients ; i < sv_maxclients->integer ; i++,cl++ ) {
		// message times may be wrong across a changelevel
		if ( cl->lastPacketTime > svs.time ) {
			cl->lastPacketTime = svs.time;
		}

		if ( cl->state == CS_ZOMBIE
			 && cl->lastPacketTime < zombiepoint ) {
			Com_DPrintf( "Going from CS_ZOMBIE to CS_FREE for %s\n", cl->name );
			cl->state = CS_FREE;    // can now be reused
			continue;
		}
		// Ridah, AI's don't time out
		if ( cl->gentity && !( cl->gentity->r.svFlags & SVF_CASTAI ) ) {
			if ( cl->state >= CS_CONNECTED && cl->lastPacketTime < droppoint ) {
				// wait several frames so a debugger session doesn't
				// cause a timeout
				if ( ++cl->timeoutCount > 5 ) {
					SV_DropClient( cl, "timed out" );
					cl->state = CS_FREE;    // don't bother with zombie state
				}
			} else {
				cl->timeoutCount = 0;
			}
		}
	}
}


/*
==================
SV_CheckPaused
==================
*/
static qboolean SV_CheckPaused( void ) {
	int count;
	client_t    *cl;
	int i;

	if ( !cl_paused->integer ) {
		return qfalse;
	}

	// only pause if there is just a single client connected
	count = 0;
	for ( i = 0,cl = svs.clients ; i < sv_maxclients->integer ; i++,cl++ ) {
		if ( cl->state >= CS_CONNECTED && cl->netchan.remoteAddress.type != NA_BOT ) {
			count++;
		}
	}

	if ( count > 1 ) {
		// don't pause
		sv_paused->integer = 0;
		return qfalse;
	}

	sv_paused->integer = 1;
	return qtrue;
}

/*
==================
SV_FrameMsec
Return time in millseconds until processing of the next server frame.
==================
*/
int SV_FrameMsec()
{
	if(sv_fps)
	{
		int frameMsec;
		
		frameMsec = 1000.0f / sv_fps->value;
		
		if(frameMsec < sv.timeResidual)
			return 0;
		else
			return frameMsec - sv.timeResidual;
	}
	else
		return 1;
}

/*
==================
SV_Frame

Player movement occurs as a result of packet events, which
happen before SV_Frame is called
==================
*/
void SV_Frame( int msec ) {
	int frameMsec;
	int startTime;

	// the menu kills the server with this cvar
	if ( sv_killserver->integer ) {
		SV_Shutdown( "Server was killed" );
		Cvar_Set( "sv_killserver", "0" );
		return;
	}

	if (!com_sv_running->integer)
	{
		// Running as a server, but no map loaded
#ifdef DEDICATED
		// Block until something interesting happens
		Sys_Sleep(-1);
#endif
		return;
	}

	// allow pause if only the local client is connected
	if ( SV_CheckPaused() ) {
		return;
	}

	// if it isn't time for the next frame, do nothing
	if ( sv_fps->integer < 1 ) {
		Cvar_Set( "sv_fps", "10" );
	}

	frameMsec = 1000 / sv_fps->integer * com_timescale->value;
	// don't let it scale below 1ms
	if(frameMsec < 1)
	{
		Cvar_Set("timescale", va("%f", sv_fps->integer / 1000.0f));
		frameMsec = 1;
	}

	sv.timeResidual += msec;

	if (!com_dedicated->integer) SV_BotFrame (sv.time + sv.timeResidual);

	// if time is about to hit the 32nd bit, kick all clients
	// and clear sv.time, rather
	// than checking for negative time wraparound everywhere.
	// 2giga-milliseconds = 23 days, so it won't be too often
	if ( svs.time > 0x70000000 ) {
		SV_Shutdown( "Restarting server due to time wrapping" );
		Cbuf_AddText( va( "spmap %s\n", Cvar_VariableString( "mapname" ) ) );
		return;
	}
	// this can happen considerably earlier when lots of clients play and the map doesn't change
	if ( svs.nextSnapshotEntities >= 0x7FFFFFFE - svs.numSnapshotEntities ) {
		SV_Shutdown( "Restarting server due to numSnapshotEntities wrapping" );
		Cbuf_AddText( va( "spmap %s\n", Cvar_VariableString( "mapname" ) ) );
		return;
	}

	if( sv.restartTime && sv.time >= sv.restartTime ) {
		sv.restartTime = 0;
		Cbuf_AddText( "map_restart 0\n" );
		return;
	}

	// update infostrings if anything has been changed
	if ( cvar_modifiedFlags & CVAR_SERVERINFO ) {
		SV_SetConfigstring( CS_SERVERINFO, Cvar_InfoString( CVAR_SERVERINFO ) );
		cvar_modifiedFlags &= ~CVAR_SERVERINFO;
	}
	if ( cvar_modifiedFlags & CVAR_SYSTEMINFO ) {
		SV_SetConfigstring( CS_SYSTEMINFO, Cvar_InfoString_Big( CVAR_SYSTEMINFO ) );
		cvar_modifiedFlags &= ~CVAR_SYSTEMINFO;
	}

	if ( com_speeds->integer ) {
		startTime = Sys_Milliseconds();
	} else {
		startTime = 0;  // quiet a compiler warning
	}

	// update ping based on the all received frames
	SV_CalcPings();

	if ( com_dedicated->integer ) {
		SV_BotFrame( sv.time );
	}

	// run the game simulation in chunks
	while ( sv.timeResidual >= frameMsec ) {
		sv.timeResidual -= frameMsec;
		svs.time += frameMsec;
		sv.time += frameMsec;

		// let everything in the world think and move
		VM_Call( gvm, GAME_RUN_FRAME, sv.time );
	}

	if ( com_speeds->integer ) {
		time_game = Sys_Milliseconds() - startTime;
	}

	// check timeouts
	SV_CheckTimeouts();

	// send messages back to the clients
	SV_SendClientMessages();

	// send a heartbeat to the master if needed
	SV_MasterHeartbeat(HEARTBEAT_FOR_MASTER);
}

/*
====================
SV_RateMsec

Return the number of msec until another message can be sent to
a client based on its rate settings
====================
*/

#define UDPIP_HEADER_SIZE 28
#define UDPIP6_HEADER_SIZE 48

int SV_RateMsec(client_t *client)
{
	int rate, rateMsec;
	int messageSize;
	
	messageSize = client->netchan.lastSentSize;
	rate = client->rate;

	if(sv_maxRate->integer)
	{
		if(sv_maxRate->integer < 1000)
			Cvar_Set( "sv_MaxRate", "1000" );
		if(sv_maxRate->integer < rate)
			rate = sv_maxRate->integer;
	}

	if(sv_minRate->integer)
	{
		if(sv_minRate->integer < 1000)
			Cvar_Set("sv_minRate", "1000");
		if(sv_minRate->integer > rate)
			rate = sv_minRate->integer;
	}

	if(client->netchan.remoteAddress.type == NA_IP6)
		messageSize += UDPIP6_HEADER_SIZE;
	else
		messageSize += UDPIP_HEADER_SIZE;
		
	rateMsec = messageSize * 1000 / ((int) (rate * com_timescale->value));
	rate = Sys_Milliseconds() - client->netchan.lastSentTime;
	
	if(rate > rateMsec)
		return 0;
	else
		return rateMsec - rate;
}

/*
====================
SV_SendQueuedPackets

Send download messages and queued packets in the time that we're idle, i.e.
not computing a server frame or sending client snapshots.
Return the time in msec until we expect to be called next
====================
*/

int SV_SendQueuedPackets()
{
	int numBlocks;
	int dlStart, deltaT, delayT;
	static int dlNextRound = 0;
	int timeVal = INT_MAX;

	// Send out fragmented packets now that we're idle
	delayT = SV_SendQueuedMessages();
	if(delayT >= 0)
		timeVal = delayT;

	if(sv_dlRate->integer)
	{
		// Rate limiting. This is very imprecise for high
		// download rates due to millisecond timedelta resolution
		dlStart = Sys_Milliseconds();
		deltaT = dlNextRound - dlStart;

		if(deltaT > 0)
		{
			if(deltaT < timeVal)
				timeVal = deltaT + 1;
		}
		else
		{
			numBlocks = SV_SendDownloadMessages();

			if(numBlocks)
			{
				// There are active downloads
				deltaT = Sys_Milliseconds() - dlStart;

				delayT = 1000 * numBlocks * MAX_DOWNLOAD_BLKSIZE;
				delayT /= sv_dlRate->integer * 1024;

				if(delayT <= deltaT + 1)
				{
					// Sending the last round of download messages
					// took too long for given rate, don't wait for
					// next round, but always enforce a 1ms delay
					// between DL message rounds so we don't hog
					// all of the bandwidth. This will result in an
					// effective maximum rate of 1MB/s per user, but the
					// low download window size limits this anyways.
					if(timeVal > 2)
						timeVal = 2;

					dlNextRound = dlStart + deltaT + 1;
				}
				else
				{
					dlNextRound = dlStart + delayT;
					delayT -= deltaT;

					if(delayT < timeVal)
						timeVal = delayT;
				}
			}
		}
	}
	else
	{
		if(SV_SendDownloadMessages())
			timeVal = 0;
	}

	return timeVal;
}

