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diff --git a/src/master/messages.c b/src/master/messages.c
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+/*
+ 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;
+ }
+
+ // 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;
+ }
+}