Initial import.

1 files changed, 877 insertions, 0 deletions

diff --git a/src/master/master.c b/src/master/master.c
new file mode 100644
index 0000000..fd6e66f
--- /dev/null
+++ b/src/master/master.c
@@ -0,0 +1,877 @@
+/*
+	master.c
+
+	A master server for Tremulous
+
+	Copyright (C) 2002-2005  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 <stdarg.h>
+#include <signal.h>
+#include <ctype.h>
+
+#ifndef WIN32
+# include <pwd.h>
+# include <unistd.h>
+#endif
+
+#include "common.h"
+#include "messages.h"
+#include "servers.h"
+
+
+// ---------- Constants ---------- //
+
+// Version of dpmaster
+#define VERSION "1.6"
+
+// Default master port
+#define DEFAULT_MASTER_PORT 30710
+
+// Maximum and minimum sizes for a valid packet
+#define MAX_PACKET_SIZE 2048
+#define MIN_PACKET_SIZE 5
+
+#ifndef WIN32
+// Default path we use for chroot
+# define DEFAULT_JAIL_PATH "/var/empty/"
+
+// User we use by default for dropping super-user privileges
+# define DEFAULT_LOW_PRIV_USER "nobody"
+#endif
+
+
+// ---------- Types ---------- //
+
+#ifdef WIN32
+typedef int socklen_t;
+#endif
+
+
+// ---------- Private variables ---------- //
+
+// The port we use
+static unsigned short master_port = DEFAULT_MASTER_PORT;
+
+// Local address we listen on, if any
+static const char* listen_name = NULL;
+static struct in_addr listen_addr;
+
+#ifndef WIN32
+// On UNIX systems, we can run as a daemon
+static qboolean daemon_mode = qfalse;
+
+// Path we use for chroot
+static const char* jail_path = DEFAULT_JAIL_PATH;
+
+// Low privileges user
+static const char* low_priv_user = DEFAULT_LOW_PRIV_USER;
+#endif
+
+
+// ---------- Public variables ---------- //
+
+// The master socket
+int inSock = -1;
+int outSock = -1;
+
+// The current time (updated every time we receive a packet)
+time_t crt_time;
+
+// Maximum level for a message to be printed
+msg_level_t max_msg_level = MSG_NORMAL;
+
+// Peer address. We rebuild it every time we receive a new packet
+char peer_address [128];
+
+
+// ---------- Private functions ---------- //
+
+/*
+====================
+PrintPacket
+
+Print the contents of a packet on stdout
+====================
+*/
+static void PrintPacket (const char* packet, size_t length)
+{
+	size_t i;
+
+	// Exceptionally, we use MSG_NOPRINT here because if the function is
+	// called, the user probably wants this text to be displayed
+	// whatever the maximum message level is.
+	MsgPrint (MSG_NOPRINT, "\"");
+
+	for (i = 0; i < length; i++)
+	{
+		char c = packet[i];
+		if (c == '\\')
+			MsgPrint (MSG_NOPRINT, "\\\\");
+		else if (c == '\"')
+			MsgPrint (MSG_NOPRINT, "\"");
+		else if (c >= 32 && (qbyte)c <= 127)
+		 	MsgPrint (MSG_NOPRINT, "%c", c);
+		else
+			MsgPrint (MSG_NOPRINT, "\\x%02X", c);
+	}
+
+	MsgPrint (MSG_NOPRINT, "\" (%u bytes)\n", length);
+}
+
+
+/*
+====================
+SysInit
+
+System dependent initializations
+====================
+*/
+static qboolean SysInit (void)
+{
+#ifdef WIN32
+	WSADATA winsockdata;
+
+	if (WSAStartup (MAKEWORD (1, 1), &winsockdata))
+	{
+		MsgPrint (MSG_ERROR, "ERROR: can't initialize winsocks\n");
+		return qfalse;
+	}
+#endif
+
+	return qtrue;
+}
+
+
+/*
+====================
+UnsecureInit
+
+System independent initializations, called BEFORE the security initializations.
+We need this intermediate step because DNS requests may not be able to resolve
+after the security initializations, due to chroot.
+====================
+*/
+static qboolean UnsecureInit (void)
+{
+	// Resolve the address mapping list
+	if (! Sv_ResolveAddressMappings ())
+		return qfalse;
+
+	// Resolve the listen address if one was specified
+	if (listen_name != NULL)
+	{
+		struct hostent* itf;
+
+		itf = gethostbyname (listen_name);
+		if (itf == NULL)
+		{
+			MsgPrint (MSG_ERROR, "ERROR: can't resolve %s\n", listen_name);
+			return qfalse;
+		}
+		if (itf->h_addrtype != AF_INET)
+		{
+			MsgPrint (MSG_ERROR, "ERROR: %s is not an IPv4 address\n",
+					  listen_name);
+			return qfalse;
+		}
+
+		memcpy (&listen_addr.s_addr, itf->h_addr,
+				sizeof (listen_addr.s_addr));
+	}
+
+	return qtrue;
+}
+
+
+/*
+====================
+SecInit
+
+Security initializations (system dependent)
+====================
+*/
+static qboolean SecInit (void)
+{
+#ifndef WIN32
+	// Should we run as a daemon?
+	if (daemon_mode && daemon (0, 0))
+	{
+		MsgPrint (MSG_NOPRINT, "ERROR: daemonization failed (%s)\n",
+				  strerror (errno));
+		return qfalse;
+	}
+
+	// UNIX allows us to be completely paranoid, so let's go for it
+	if (geteuid () == 0)
+	{
+		struct passwd* pw;
+
+		MsgPrint (MSG_WARNING,
+				  "WARNING: running with super-user privileges\n");
+
+		// We must get the account infos before the calls to chroot and chdir
+		pw = getpwnam (low_priv_user);
+		if (pw == NULL)
+		{
+			MsgPrint (MSG_ERROR, "ERROR: can't get user \"%s\" properties\n",
+					  low_priv_user);
+			return qfalse;
+		}
+
+		// Chroot ourself
+		MsgPrint (MSG_NORMAL, "  - chrooting myself to %s... ", jail_path);
+		if (chroot (jail_path) || chdir ("/"))
+		{
+			MsgPrint (MSG_ERROR, "FAILED (%s)\n", strerror (errno));
+			return qfalse;
+		}
+		MsgPrint (MSG_NORMAL, "succeeded\n");
+
+		// Switch to lower privileges
+		MsgPrint (MSG_NORMAL, "  - switching to user \"%s\" privileges... ",
+				  low_priv_user);
+		if (setgid (pw->pw_gid) || setuid (pw->pw_uid))
+		{
+			MsgPrint (MSG_ERROR, "FAILED (%s)\n", strerror (errno));
+			return qfalse;
+		}
+		MsgPrint (MSG_NORMAL, "succeeded (UID: %u, GID: %u)\n",
+				  pw->pw_uid, pw->pw_gid);
+
+		MsgPrint (MSG_NORMAL, "\n");
+	}
+#endif
+
+	return qtrue;
+}
+
+
+/*
+====================
+ParseCommandLine
+
+Parse the options passed by the command line
+====================
+*/
+static qboolean ParseCommandLine (int argc, const char* argv [])
+{
+	int ind = 1;
+	unsigned int vlevel = max_msg_level;
+	qboolean valid_options = qtrue;
+
+	while (ind < argc && valid_options)
+	{
+		// If it doesn't even look like an option, why bother?
+		if (argv[ind][0] != '-')
+			valid_options = qfalse;
+
+		else switch (argv[ind][1])
+		{
+#ifndef WIN32
+			// Daemon mode
+			case 'D':
+				daemon_mode = qtrue;
+				break;
+#endif
+
+			// Help
+			case 'h':
+				valid_options = qfalse;
+				break;
+
+			// Hash size
+			case 'H':
+				ind++;
+				if (ind < argc)
+					valid_options = Sv_SetHashSize (atoi (argv[ind]));
+				else
+					valid_options = qfalse;
+				break;
+
+#ifndef WIN32
+			// Jail path
+			case 'j':
+				ind++;
+				if (ind < argc)
+					jail_path = argv[ind];
+				else
+					valid_options = qfalse;
+				break;
+#endif
+
+			// Listen address
+			case 'l':
+				ind++;
+				if (ind >= argc || argv[ind][0] == '\0')
+					valid_options = qfalse;
+				else
+					listen_name = argv[ind];
+				break;
+
+			// Address mapping
+			case 'm':
+				ind++;
+				if (ind < argc)
+					valid_options = Sv_AddAddressMapping (argv[ind]);
+				else
+					valid_options = qfalse;
+				break;
+
+			// Maximum number of servers
+			case 'n':
+				ind++;
+				if (ind < argc)
+					valid_options = Sv_SetMaxNbServers (atoi (argv[ind]));
+				else
+					valid_options = qfalse;
+				break;
+
+			// Port number
+			case 'p':
+			{
+				unsigned short port_num = 0;
+				ind++;
+				if (ind < argc)
+					port_num = atoi (argv[ind]);
+				if (!port_num)
+					valid_options = qfalse;
+				else
+					master_port = port_num;
+				break;
+			}
+
+#ifndef WIN32
+			// Low privileges user
+			case 'u':
+				ind++;
+				if (ind < argc)
+					low_priv_user = argv[ind];
+				else
+					valid_options = qfalse;
+				break;
+#endif
+
+			// Verbose level
+			case 'v':
+				// If a verbose level has been specified
+				if (ind + 1 < argc && argv[ind + 1][0] != '-')
+				{
+					ind++;
+					vlevel = atoi (argv[ind]);
+					if (vlevel > MSG_DEBUG)
+						valid_options = qfalse;
+				}
+				else
+					vlevel = MSG_DEBUG;
+				break;
+
+			default:
+				valid_options = qfalse;
+		}
+
+		ind++;
+	}
+
+	// If the command line is OK, we can set the verbose level now
+	if (valid_options)
+	{
+#ifndef WIN32
+		// If we run as a daemon, don't bother printing anything
+		if (daemon_mode)
+			max_msg_level = MSG_NOPRINT;
+		else
+#endif
+			max_msg_level = vlevel;
+	}
+
+	return valid_options;
+}
+
+
+/*
+====================
+PrintHelp
+
+Print the command line syntax and the available options
+====================
+*/
+static void PrintHelp (void)
+{
+	MsgPrint (MSG_ERROR,
+			  "Syntax: dpmaster [options]\n"
+			  "Available options are:\n"
+#ifndef WIN32
+			  "  -D               : run as a daemon\n"
+#endif
+			  "  -h               : this help\n"
+			  "  -H <hash_size>   : hash size in bits, up to %u (default: %u)\n"
+#ifndef WIN32
+			  "  -j <jail_path>   : use <jail_path> as chroot path (default: %s)\n"
+			  "                     only available when running with super-user privileges\n"
+#endif
+			  "  -l <address>     : listen on local address <address>\n"
+			  "  -m <a1>=<a2>     : map address <a1> to <a2> when sending it to clients\n"
+			  "                     addresses can contain a port number (ex: myaddr.net:1234)\n"
+			  "  -n <max_servers> : maximum number of servers recorded (default: %u)\n"
+			  "  -p <port_num>    : use port <port_num> (default: %u)\n"
+#ifndef WIN32
+			  "  -u <user>        : use <user> privileges (default: %s)\n"
+			  "                     only available when running with super-user privileges\n"
+#endif
+			  "  -v [verbose_lvl] : verbose level, up to %u (default: %u; no value means max)\n"
+			  "\n",
+			  MAX_HASH_SIZE, DEFAULT_HASH_SIZE,
+#ifndef WIN32
+			  DEFAULT_JAIL_PATH,
+#endif
+			  DEFAULT_MAX_NB_SERVERS,
+			  DEFAULT_MASTER_PORT,
+#ifndef WIN32
+			  DEFAULT_LOW_PRIV_USER,
+#endif
+			  MSG_DEBUG, MSG_NORMAL);
+}
+
+
+/*
+====================
+SecureInit
+
+System independent initializations, called AFTER the security initializations
+====================
+*/
+static qboolean SecureInit (void)
+{
+	struct sockaddr_in address;
+
+	// Init the time and the random seed
+	crt_time = time (NULL);
+	srand (crt_time);
+
+	// Initialize the server list and hash table
+	if (!Sv_Init ())
+		return qfalse;
+
+	// Open the socket
+	inSock = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (inSock < 0)
+	{
+		MsgPrint (MSG_ERROR, "ERROR: socket creation failed (%s)\n",
+				  strerror (errno));
+		return qfalse;
+	}
+
+	outSock = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (outSock < 0)
+	{
+		MsgPrint (MSG_ERROR, "ERROR: socket creation failed (%s)\n",
+				  strerror (errno));
+		return qfalse;
+	}
+
+	// Bind it to the master port
+	memset (&address, 0, sizeof (address));
+	address.sin_family = AF_INET;
+	if (listen_name != NULL)
+	{
+		MsgPrint (MSG_NORMAL, "Listening on address %s (%s)\n",
+				  listen_name, inet_ntoa (listen_addr));
+		address.sin_addr.s_addr = listen_addr.s_addr;
+	}
+	else
+		address.sin_addr.s_addr = htonl (INADDR_ANY);
+
+	address.sin_port = htons (master_port);
+	if (bind (inSock, (struct sockaddr*)&address, sizeof (address)) != 0)
+	{
+		MsgPrint (MSG_ERROR, "ERROR: socket binding failed (%s)\n",
+				  strerror (errno));
+#ifdef WIN32
+		closesocket (inSock);
+#else
+		close (inSock);
+#endif
+		return qfalse;
+	}
+	MsgPrint (MSG_NORMAL, "Listening on UDP port %hu\n",
+			  ntohs (address.sin_port));
+
+	// Deliberately use a different port for outgoing traffic in order
+	// to confuse NAT UDP "connection" tracking and thus delist servers
+	// hidden by NAT
+	address.sin_port = htons (master_port+1);
+	if (bind (outSock, (struct sockaddr*)&address, sizeof (address)) != 0)
+	{
+		MsgPrint (MSG_ERROR, "ERROR: socket binding failed (%s)\n",
+				  strerror (errno));
+#ifdef WIN32
+		closesocket (outSock);
+#else
+		close (outSock);
+#endif
+		return qfalse;
+	}
+
+	return qtrue;
+}
+
+static qboolean exitNow = qfalse;
+
+/*
+===============
+cleanUp
+
+Clean up
+===============
+*/
+static void cleanUp( int signal )
+{
+	MsgPrint( MSG_NORMAL, "Caught signal %d, exiting...\n", signal );
+
+	exitNow = qtrue;
+}
+
+#define ADDRESS_LENGTH 16
+static const char *ignoreFile = "ignore.txt";
+
+typedef struct
+{
+	char address[ ADDRESS_LENGTH ]; // Dotted quad
+} ignoreAddress_t;
+
+#define PARSE_INTERVAL		10 // seconds
+
+static time_t							lastParseTime				= 0;
+static int								numIgnoreAddresses	= 0;
+static ignoreAddress_t		*ignoreAddresses		= NULL;
+
+/*
+====================
+parseIgnoreAddress
+====================
+*/
+static qboolean parseIgnoreAddress( void )
+{
+	int		numAllocIgnoreAddresses	= 1;
+	FILE	*f											= NULL;
+	int		i;
+
+	// Only reparse periodically
+	if( crt_time - lastParseTime < PARSE_INTERVAL )
+		return qtrue;
+
+	lastParseTime = time( NULL );
+
+	// Free existing list
+	if( ignoreAddresses != NULL )
+	{
+		free( ignoreAddresses );
+		ignoreAddresses = NULL;
+	}
+
+	numIgnoreAddresses			= 0;
+	ignoreAddresses					= malloc( sizeof( ignoreAddress_t ) * numAllocIgnoreAddresses );
+
+	// Alloc failed, fail parsing
+	if( ignoreAddresses == NULL )
+		return qfalse;
+
+	f = fopen( ignoreFile, "r" );
+
+	if( !f )
+	{
+		free( ignoreAddresses );
+		ignoreAddresses = NULL;
+		return qfalse;
+	}
+
+	while( !feof( f ) )
+	{
+		char	c;
+		char	buffer[ ADDRESS_LENGTH ];
+
+		i = 0;
+
+		// Skip whitespace
+		do
+		{
+			c = fgetc( f );
+		}
+		while( c != EOF && isspace( c ) );
+
+		if( c != EOF )
+		{
+			do
+			{
+				if( i >= ADDRESS_LENGTH )
+				{
+					buffer[ i - 1 ] = '\0';
+					break;
+				}
+
+				buffer[ i ] = c;
+
+				if( isspace( c ) )
+				{
+					buffer[ i ] = '\0';
+					break;
+				}
+
+				i++;
+			} while( ( c = fgetc( f ) ) != EOF );
+
+			strcpy( ignoreAddresses[ numIgnoreAddresses ].address, buffer );
+
+			numIgnoreAddresses++;
+
+			// Make list bigger
+			if( numIgnoreAddresses >= numAllocIgnoreAddresses )
+			{
+				ignoreAddress_t *new;
+
+				numAllocIgnoreAddresses *= 2;
+				new = realloc( ignoreAddresses,
+						sizeof( ignoreAddress_t ) * numAllocIgnoreAddresses );
+
+				// Alloc failed, fail parsing
+				if( new == NULL )
+				{
+					fclose( f );
+					free( ignoreAddresses );
+					ignoreAddresses = NULL;
+					return qfalse;
+				}
+
+				ignoreAddresses = new;
+			}
+		}
+	}
+
+	fclose( f );
+
+	return qtrue;
+}
+
+/*
+====================
+ignoreAddress
+
+Check whether or not to ignore a specific address
+====================
+*/
+static qboolean ignoreAddress( const char *address )
+{
+	int i;
+
+	if( !parseIgnoreAddress( ) )
+	{
+		// Couldn't parse, allow the address
+		return qfalse;
+	}
+
+	for( i = 0; i < numIgnoreAddresses; i++ )
+	{
+		if( strcmp( address, ignoreAddresses[ i ].address ) == 0 )
+			break;
+	}
+
+	// It matched
+	if( i < numIgnoreAddresses )
+		return qtrue;
+
+	return qfalse;
+}
+
+/*
+====================
+max
+
+Maximum of two ints
+====================
+*/
+static inline int max( int a, int b )
+{
+	return a > b ? a : b;
+}
+
+/*
+====================
+main
+
+Main function
+====================
+*/
+int main (int argc, const char* argv [])
+{
+	struct sockaddr_in address;
+	socklen_t addrlen;
+	int nb_bytes;
+	int sock;
+	char packet [MAX_PACKET_SIZE + 1];  // "+ 1" because we append a '\0'
+	qboolean valid_options;
+	fd_set rfds;
+	struct timeval tv;
+
+
+	signal( SIGINT, cleanUp );
+	signal( SIGTERM, cleanUp );
+
+	// Get the options from the command line
+	valid_options = ParseCommandLine (argc, argv);
+
+	MsgPrint (MSG_NORMAL,
+			"tremmaster (version " VERSION " " __DATE__ " " __TIME__ ")\n" );
+
+	// If there was a mistake in the command line, print the help and exit
+	if (!valid_options)
+	{
+		PrintHelp ();
+		return EXIT_FAILURE;
+	}
+
+	// Initializations
+	if (!SysInit () || !UnsecureInit () || !SecInit () || !SecureInit ())
+		return EXIT_FAILURE;
+	MsgPrint (MSG_NORMAL, "\n");
+
+	// Until the end of times...
+	while( !exitNow )
+	{
+		FD_ZERO( &rfds );
+		FD_SET( inSock, &rfds );
+		FD_SET( outSock, &rfds );
+		tv.tv_sec = tv.tv_usec = 0;
+
+		// Check for new data every 100ms
+		if( select( max( inSock, outSock ) + 1, &rfds, NULL, NULL, &tv ) <= 0 )
+		{
+#ifdef _WIN32
+			Sleep( 100 );
+#else
+			usleep( 100000 );
+#endif
+			continue;
+		}
+
+		if( FD_ISSET( inSock, &rfds ) )
+			sock = inSock;
+		else if( FD_ISSET( outSock, &rfds ) )
+			sock = outSock;
+		else
+			continue;
+
+		// Get the next valid message
+		addrlen = sizeof (address);
+		nb_bytes = recvfrom (sock, packet, sizeof (packet) - 1, 0,
+							 (struct sockaddr*)&address, &addrlen);
+		if (nb_bytes <= 0)
+		{
+			MsgPrint (MSG_WARNING,
+					  "WARNING: \"recvfrom\" returned %d\n", nb_bytes);
+			continue;
+		}
+
+		// If we may have to print something, rebuild the peer address buffer
+		if (max_msg_level != MSG_NOPRINT)
+			snprintf (peer_address, sizeof (peer_address), "%s:%hu",
+					  inet_ntoa (address.sin_addr), ntohs (address.sin_port));
+
+		// Ignore abusers
+		if( ignoreAddress( inet_ntoa( address.sin_addr ) ) )
+		{
+			server_t* abuser = Sv_GetByAddr( &address, qfalse );
+			if( abuser != NULL )
+			{
+				abuser->timeout = crt_time - 1;
+				Sv_GetByAddr( &address, qfalse );
+				MsgPrint( MSG_WARNING, "WARNING: removing abuser %s\n", peer_address );
+			}
+			continue;
+		}
+
+		// We print the packet contents if necessary
+		// TODO: print the current time here
+		if (max_msg_level >= MSG_DEBUG)
+		{
+			MsgPrint (MSG_DEBUG, "New packet received from %s: ",
+					  peer_address);
+			PrintPacket (packet, nb_bytes);
+		}
+
+		// A few sanity checks
+		if (nb_bytes < MIN_PACKET_SIZE)
+		{
+			MsgPrint (MSG_WARNING,
+					  "WARNING: rejected packet from %s (size = %d bytes)\n",
+					  peer_address, nb_bytes);
+			continue;
+		}
+		if (*((unsigned int*)packet) != 0xFFFFFFFF)
+		{
+			MsgPrint (MSG_WARNING,
+					  "WARNING: rejected packet from %s (invalid header)\n",
+					  peer_address);
+			continue;
+		}
+		if( ntohs( address.sin_port ) < 1024 )
+		{
+			MsgPrint (MSG_WARNING,
+					  "WARNING: rejected packet from %s (source port = 0)\n",
+					  peer_address);
+			continue;
+		}
+
+		// Append a '\0' to make the parsing easier and update the current time
+		packet[nb_bytes] = '\0';
+		crt_time = time (NULL);
+
+		// Call HandleMessage with the remaining contents
+		HandleMessage (packet + 4, nb_bytes - 4, &address);
+	}
+
+	return 0;
+}
+
+
+// ---------- Public functions ---------- //
+
+/*
+====================
+MsgPrint
+
+Print a message to screen, depending on its verbose level
+====================
+*/
+int MsgPrint (msg_level_t msg_level, const char* format, ...)
+{
+	va_list args;
+	int result;
+
+	// If the message level is above the maximum level, don't print it
+	if (msg_level > max_msg_level)
+		return 0;
+
+	va_start (args, format);
+	result = vprintf (format, args);
+	va_end (args);
+
+	fflush (stdout);
+
+	return result;
+}