Initial import.

1 files changed, 574 insertions, 0 deletions

diff --git a/src/master/messages.c b/src/master/messages.c
new file mode 100644
index 0000000..a86e795
--- /dev/null
+++ b/src/master/messages.c
@@ -0,0 +1,574 @@
+/*
+	messages.c
+
+	Message management for tremmaster
+
+	Copyright (C) 2004  Mathieu Olivier
+
+	This program 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 2 of the License, or
+	(at your option) any later version.
+
+	This program 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 this program; if not, write to the Free Software
+	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+
+#include "common.h"
+#include "messages.h"
+#include "servers.h"
+
+
+// ---------- Constants ---------- //
+
+// Timeouts (in secondes)
+#define TIMEOUT_HEARTBEAT		2
+#define TIMEOUT_INFORESPONSE	(15 * 60)
+
+// Period of validity for a challenge string (in secondes)
+#define TIMEOUT_CHALLENGE 2
+
+// Maximum size of a reponse packet
+#define MAX_PACKET_SIZE 1400
+
+
+// Types of messages (with samples):
+
+// "heartbeat Tremulous\n"
+#define S2M_HEARTBEAT "heartbeat"
+
+// "gamestat <data>"
+#define S2M_GAMESTAT "gamestat"
+
+// "getinfo A_Challenge"
+#define M2S_GETINFO "getinfo"
+
+// "infoResponse\n\\pure\\1\\..."
+#define S2M_INFORESPONSE "infoResponse\x0A"
+
+// "getservers 67 empty full"
+#define C2M_GETSERVERS "getservers "
+
+// "getserversResponse\\...(6 bytes)...\\...(6 bytes)...\\EOT\0\0\0"
+#define M2C_GETSERVERSREPONSE "getserversResponse"
+
+#define C2M_GETMOTD "getmotd"
+#define M2C_MOTD    "motd "
+
+
+// ---------- Private functions ---------- //
+
+/*
+====================
+SearchInfostring
+
+Search an infostring for the value of a key
+====================
+*/
+static char* SearchInfostring (const char* infostring, const char* key)
+{
+	static char value [256];
+	char crt_key [256];
+	size_t value_ind, key_ind;
+	char c;
+
+	if (*infostring++ != '\\')
+		return NULL;
+
+	value_ind = 0;
+	for (;;)
+	{
+		key_ind = 0;
+
+		// Get the key name
+		for (;;)
+		{
+			c = *infostring++;
+
+			if (c == '\0')
+				return NULL;
+			if (c == '\\' || key_ind == sizeof (crt_key) - 1)
+			{
+				crt_key[key_ind] = '\0';
+				break;
+			}
+
+			crt_key[key_ind++] = c;
+		}
+
+		// If it's the key we are looking for, save it in "value"
+		if (!strcmp (crt_key, key))
+		{
+			for (;;)
+			{
+				c = *infostring++;
+
+				if (c == '\0' || c == '\\' || value_ind == sizeof (value) - 1)
+				{
+					value[value_ind] = '\0';
+					return value;
+				}
+
+				value[value_ind++] = c;
+			}
+		}
+
+		// Else, skip the value
+		for (;;)
+		{
+			c = *infostring++;
+
+			if (c == '\0')
+				return NULL;
+			if (c == '\\')
+				break;
+		}
+	}
+}
+
+
+/*
+====================
+BuildChallenge
+
+Build a challenge string for a "getinfo" message
+====================
+*/
+static const char* BuildChallenge (void)
+{
+	static char challenge [CHALLENGE_MAX_LENGTH];
+	size_t ind;
+	size_t length = CHALLENGE_MIN_LENGTH - 1;  // We start at the minimum size
+
+	// ... then we add a random number of characters
+	length += rand () % (CHALLENGE_MAX_LENGTH - CHALLENGE_MIN_LENGTH + 1);
+
+	for (ind = 0; ind < length; ind++)
+	{
+		char c;
+		do
+		{
+			c = 33 + rand () % (126 - 33 + 1);  // -> c = 33..126
+		} while (c == '\\' || c == ';' || c == '"' || c == '%' || c == '/');
+
+		challenge[ind] = c;
+	}
+
+	challenge[length] = '\0';
+	return challenge;
+}
+
+
+/*
+====================
+SendGetInfo
+
+Send a "getinfo" message to a server
+====================
+*/
+static void SendGetInfo (server_t* server)
+{
+	char msg [64] = "\xFF\xFF\xFF\xFF" M2S_GETINFO " ";
+
+	if (!server->challenge_timeout || server->challenge_timeout < crt_time)
+	{
+		strncpy (server->challenge, BuildChallenge (),
+				 sizeof (server->challenge) - 1);
+		server->challenge_timeout = crt_time + TIMEOUT_CHALLENGE;
+	}
+
+	strncat (msg, server->challenge, sizeof (msg) - strlen (msg) - 1);
+	sendto (outSock, msg, strlen (msg), 0,
+			(const struct sockaddr*)&server->address,
+			sizeof (server->address));
+
+	MsgPrint (MSG_DEBUG, "%s <--- getinfo with challenge \"%s\"\n",
+			  peer_address, server->challenge);
+}
+
+
+/*
+====================
+HandleGetServers
+
+Parse getservers requests and send the appropriate response
+====================
+*/
+static void HandleGetServers (const char* msg, const struct sockaddr_in* addr)
+{
+	const char* packetheader = "\xFF\xFF\xFF\xFF" M2C_GETSERVERSREPONSE "\\";
+	const size_t headersize = strlen (packetheader);
+	char packet [MAX_PACKET_SIZE];
+	size_t packetind;
+	server_t* sv;
+	unsigned int protocol;
+	unsigned int sv_addr;
+	unsigned short sv_port;
+	qboolean no_empty;
+	qboolean no_full;
+	unsigned int numServers = 0;
+
+	// Check if there's a name before the protocol number
+	// In this case, the message comes from a DarkPlaces-compatible client
+	protocol = atoi (msg);
+
+	MsgPrint (MSG_NORMAL, "%s ---> getservers( protocol version %d )\n",
+			peer_address, protocol );
+
+	no_empty = (strstr (msg, "empty") == NULL);
+	no_full = (strstr (msg, "full") == NULL);
+
+	// Initialize the packet contents with the header
+	packetind = headersize;
+	memcpy(packet, packetheader, headersize);
+
+	// Add every relevant server
+	for (sv = Sv_GetFirst (); /* see below */;  sv = Sv_GetNext ())
+	{
+		// If we're done, or if the packet is full, send the packet
+		if (sv == NULL || packetind > sizeof (packet) - (7 + 6))
+		{
+			// End Of Transmission
+			packet[packetind    ] = 'E';
+			packet[packetind + 1] = 'O';
+			packet[packetind + 2] = 'T';
+			packet[packetind + 3] = '\0';
+			packet[packetind + 4] = '\0';
+			packet[packetind + 5] = '\0';
+			packetind += 6;
+
+			// Send the packet to the client
+			sendto (inSock, packet, packetind, 0, (const struct sockaddr*)addr,
+					sizeof (*addr));
+
+			MsgPrint (MSG_DEBUG, "%s <--- getserversResponse (%u servers)\n",
+						peer_address, numServers);
+
+			// If we're done
+			if (sv == NULL)
+				return;
+			
+			// Reset the packet index (no need to change the header)
+			packetind = headersize;
+		}
+
+		sv_addr = ntohl (sv->address.sin_addr.s_addr);
+		sv_port = ntohs (sv->address.sin_port);
+
+		// Extra debugging info
+		if (max_msg_level >= MSG_DEBUG)
+		{
+			MsgPrint (MSG_DEBUG,
+					  "Comparing server: IP:\"%u.%u.%u.%u:%hu\", p:%u, c:%hu\n",
+					  sv_addr >> 24, (sv_addr >> 16) & 0xFF,
+					  (sv_addr >>  8) & 0xFF, sv_addr & 0xFF,
+					  sv_port, sv->protocol, sv->nbclients );
+
+			if (sv->protocol != protocol)
+				MsgPrint (MSG_DEBUG,
+						  "Reject: protocol %u != requested %u\n",
+						  sv->protocol, protocol);
+			if (sv->nbclients == 0 && no_empty)
+				MsgPrint (MSG_DEBUG,
+						  "Reject: nbclients is %hu/%hu && no_empty\n",
+						  sv->nbclients, sv->maxclients);
+			if (sv->nbclients == sv->maxclients && no_full)
+				MsgPrint (MSG_DEBUG,
+						  "Reject: nbclients is %hu/%hu && no_full\n",
+						  sv->nbclients, sv->maxclients);
+		}
+
+		// Check protocol, options
+		if (sv->protocol != protocol ||
+			(sv->nbclients == 0 && no_empty) ||
+			(sv->nbclients == sv->maxclients && no_full))
+		{
+
+			// Skip it
+			continue;
+		}
+
+		// Use the address mapping associated with the server, if any
+		if (sv->addrmap != NULL)
+		{
+			const addrmap_t* addrmap = sv->addrmap;
+
+			sv_addr = ntohl (addrmap->to.sin_addr.s_addr);
+			if (addrmap->to.sin_port != 0)
+				sv_port = ntohs (addrmap->to.sin_port);
+
+			MsgPrint (MSG_DEBUG,
+					  "Server address mapped to %u.%u.%u.%u:%hu\n",
+					  sv_addr >> 24, (sv_addr >> 16) & 0xFF,
+					  (sv_addr >>  8) & 0xFF, sv_addr & 0xFF,
+					  sv_port);
+		}
+
+		// IP address
+		packet[packetind    ] =  sv_addr >> 24;
+		packet[packetind + 1] = (sv_addr >> 16) & 0xFF;
+		packet[packetind + 2] = (sv_addr >>  8) & 0xFF;
+		packet[packetind + 3] =  sv_addr        & 0xFF;
+
+		// Port
+		packet[packetind + 4] = sv_port >> 8;
+		packet[packetind + 5] = sv_port & 0xFF;
+
+		// Trailing '\'
+		packet[packetind + 6] = '\\';
+
+		MsgPrint (MSG_DEBUG, "  - Sending server %u.%u.%u.%u:%hu\n",
+				  (qbyte)packet[packetind    ], (qbyte)packet[packetind + 1],
+				  (qbyte)packet[packetind + 2], (qbyte)packet[packetind + 3],
+				  sv_port);
+
+		packetind += 7;
+		numServers++;
+	}
+}
+
+
+/*
+====================
+HandleInfoResponse
+
+Parse infoResponse messages
+====================
+*/
+static void HandleInfoResponse (server_t* server, const char* msg)
+{
+	char* value;
+	unsigned int new_protocol = 0, new_maxclients = 0;
+
+	MsgPrint (MSG_DEBUG, "%s ---> infoResponse\n", peer_address);
+
+	// Check the challenge
+	if (!server->challenge_timeout || server->challenge_timeout < crt_time)
+	{
+		MsgPrint (MSG_WARNING,
+				  "WARNING: infoResponse with obsolete challenge from %s\n",
+				  peer_address);
+		return;
+	}
+	value = SearchInfostring (msg, "challenge");
+	if (!value || strcmp (value, server->challenge))
+	{
+		MsgPrint (MSG_ERROR, "ERROR: invalid challenge from %s (%s)\n",
+				  peer_address, value);
+		return;
+	}
+	// some people enjoy making it hard to find them
+	value = SearchInfostring (msg, "hostname");
+	if (!value || !value[0])
+	{
+		MsgPrint (MSG_ERROR, "ERROR: no hostname from %s\n",
+				  peer_address, value);
+		return;
+	}
+
+	// Check and save the values of "protocol" and "maxclients"
+	value = SearchInfostring (msg, "protocol");
+	if (value)
+		new_protocol = atoi (value);
+	value = SearchInfostring (msg, "sv_maxclients");
+	if (value)
+		new_maxclients = atoi (value);
+	if (!new_protocol || !new_maxclients)
+	{
+		MsgPrint (MSG_ERROR,
+				  "ERROR: invalid infoResponse from %s (protocol: %d, maxclients: %d)\n",
+				  peer_address, new_protocol, new_maxclients);
+		return;
+	}
+	server->protocol = new_protocol;
+	server->maxclients = new_maxclients;
+
+	// Save some other useful values
+	value = SearchInfostring (msg, "clients");
+	if (value)
+		server->nbclients = atoi (value);
+
+	// Set a new timeout
+	server->timeout = crt_time + TIMEOUT_INFORESPONSE;
+}
+
+
+#define CHALLENGE_KEY "challenge\\"
+#define MOTD_KEY      "motd\\"
+
+/*
+====================
+HandleGetMotd
+
+Parse getservers requests and send the appropriate response
+====================
+*/
+static void HandleGetMotd( const char* msg, const struct sockaddr_in* addr )
+{
+	const char		*packetheader = "\xFF\xFF\xFF\xFF" M2C_MOTD "\"";
+	const size_t	headersize = strlen (packetheader);
+	char					packet[ MAX_PACKET_SIZE ];
+	char					challenge[ MAX_PACKET_SIZE ];
+	const char		*motd = ""; //FIXME
+	size_t				packetind;
+	char					*value;
+	char		version[ 1024 ], renderer[ 1024 ];
+
+	MsgPrint( MSG_DEBUG, "%s ---> getmotd\n", peer_address );
+
+	value = SearchInfostring( msg, "challenge" );
+	if( !value )
+	{
+		MsgPrint( MSG_ERROR, "ERROR: invalid challenge from %s (%s)\n",
+					peer_address, value );
+		return;
+	}
+
+	strncpy( challenge, value, sizeof(challenge)-1 );
+	challenge[sizeof(challenge)-1] = '\0';
+
+	value = SearchInfostring( msg, "renderer" );
+	if( value )
+	{
+		strncpy( renderer, value, sizeof(renderer)-1 );
+		renderer[sizeof(renderer)-1] = '\0';
+		MsgPrint( MSG_DEBUG, "%s is using renderer %s\n", peer_address, value );
+	}
+
+	value = SearchInfostring( msg, "version" );
+	if( value )
+	{
+		strncpy( version, value, sizeof(version)-1 );
+		version[sizeof(version)-1] = '\0';
+		MsgPrint( MSG_DEBUG, "%s is using version %s\n", peer_address, value );
+	}
+
+#ifndef _WIN32
+  RecordClientStat( peer_address, version, renderer );
+#endif
+
+	// Initialize the packet contents with the header
+	packetind = headersize;
+	memcpy( packet, packetheader, headersize );
+
+	strncpy( &packet[ packetind ], CHALLENGE_KEY, MAX_PACKET_SIZE - packetind - 2 );
+	packetind += strlen( CHALLENGE_KEY );
+
+	strncpy( &packet[ packetind ], challenge, MAX_PACKET_SIZE - packetind - 2 );
+	packetind += strlen( challenge );
+	packet[ packetind++ ] = '\\';
+
+	strncpy( &packet[ packetind ], MOTD_KEY, MAX_PACKET_SIZE - packetind - 2 );
+	packetind += strlen( MOTD_KEY );
+
+	strncpy( &packet[ packetind ], motd, MAX_PACKET_SIZE - packetind - 2 );
+	packetind += strlen( motd );
+
+	if (packetind > MAX_PACKET_SIZE - 2)
+		packetind = MAX_PACKET_SIZE - 2;
+	
+	packet[ packetind++ ] = '\"';
+	packet[ packetind++ ] = '\0';
+
+	MsgPrint( MSG_DEBUG, "%s <--- motd\n", peer_address );
+
+	// Send the packet to the client
+	sendto( inSock, packet, packetind, 0, (const struct sockaddr*)addr,
+			sizeof( *addr ) );
+}
+
+/*
+====================
+HandleGameStat
+====================
+*/
+static void HandleGameStat( const char* msg, const struct sockaddr_in* addr )
+{
+#ifndef _WIN32
+  RecordGameStat( peer_address, msg );
+#endif
+}
+
+// ---------- Public functions ---------- //
+
+/*
+====================
+HandleMessage
+
+Parse a packet to figure out what to do with it
+====================
+*/
+void HandleMessage (const char* msg, size_t length,
+					const struct sockaddr_in* address)
+{
+	server_t* server;
+
+	// If it's an heartbeat
+	if (!strncmp (S2M_HEARTBEAT, msg, strlen (S2M_HEARTBEAT)))
+	{
+		char gameId [64];
+
+		// Extract the game id
+		sscanf (msg + strlen (S2M_HEARTBEAT) + 1, "%63s", gameId);
+		MsgPrint (MSG_DEBUG, "%s ---> heartbeat (%s)\n",
+				  peer_address, gameId);
+
+		// Get the server in the list (add it to the list if necessary)
+		server = Sv_GetByAddr (address, qtrue);
+		if (server == NULL)
+			return;
+
+		server->active = qtrue;
+
+		// If we haven't yet received any infoResponse from this server,
+		// we let it some more time to contact us. After that, only
+		// infoResponse messages can update the timeout value.
+		if (!server->maxclients)
+			server->timeout = crt_time + TIMEOUT_HEARTBEAT;
+
+		// Ask for some infos
+		SendGetInfo (server);
+	}
+
+	// If it's an infoResponse message
+	else if (!strncmp (S2M_INFORESPONSE, msg, strlen (S2M_INFORESPONSE)))
+	{
+		server = Sv_GetByAddr (address, qfalse);
+		if (server == NULL)
+			return;
+
+		HandleInfoResponse (server, msg + strlen (S2M_INFORESPONSE));
+	}
+
+	// If it's a getservers request
+	else if (!strncmp (C2M_GETSERVERS, msg, strlen (C2M_GETSERVERS)))
+	{
+		HandleGetServers (msg + strlen (C2M_GETSERVERS), address);
+	}
+
+	// If it's a getmotd request
+	else if (!strncmp (C2M_GETMOTD, msg, strlen (C2M_GETMOTD)))
+	{
+		HandleGetMotd (msg + strlen (C2M_GETMOTD), address);
+	}
+
+  // If it's a game statistic
+  else if( !strncmp( S2M_GAMESTAT, msg, strlen ( S2M_GAMESTAT ) ) )
+  {
+    server = Sv_GetByAddr(address, qfalse);
+    if (server == NULL)
+	return;
+    if( crt_time - server->lastGameStat > MIN_GAMESTAT_DELAY )
+      HandleGameStat( msg + strlen( S2M_GAMESTAT ), address );
+    else
+      MsgPrint( MSG_NORMAL, "%s flooding GAMESTAT messages\n", peer_address );
+    server->lastGameStat = crt_time;
+  }
+}