dns_mastergold.c

来自「C实现的MUD,对大家基本入门网络游戏很有帮助!」· C语言 代码 · 共 887 行 · 第 1/2 页

			"tell"     :  SVC_UDP,
			"rwho_q"   :  SVC_UDP,
			"gwizmsg"  :  SVC_UDP,
		]);
		break;
	default: // TCP_NONE
		mud_svc[name] = ([
			"mail"     :  SVC_NO_TCP,
			"finger"   :  SVC_NO_TCP | SVC_UDP | SVC_KNOWN,
			"tell"     :  SVC_NO_TCP | SVC_UDP | SVC_KNOWN,
			"rwho_q"   :  SVC_NO_TCP | SVC_UDP | SVC_KNOWN,
			"gwizmsg"  :  SVC_NO_TCP | SVC_UDP | SVC_KNOWN,
		]);
		break;
	} // switch (tcp)

	// handle service information
	if (tcp != TCP_ONLY)
		query_services(name, junk["HOSTADDRESS"], junk["PORTUDP"], tcp);
}

// deletes an entry for a mud
void zap_mud_info(string name, mapping junk)
{
	// check permissions
	if( !previous_object()
	||	!ACCESS_CHECK(previous_object())
	||	file_name(previous_object())[0..strlen(AUX_PATH) - 1] != AUX_PATH)
		return;

	// delete the entry
	map_delete(muds, name);

	// wipe the service information
	map_delete(mud_svc, name);
}

// This is called when we get a service response from the other end
void support_q_callback(mapping info)
{
	string cmd;
	string mud;

	// check permission
	if (!ACCESS_CHECK(previous_object())) return;

	// check the reply is valid - note that if info is 0 it is possible
	// this is the result of a tiemout, but as muds are only queried
	// once, and the default is unknown, we dont have a problem.
	if (!info || !info["CMD"] || !info["NAME"] || !strlen(info["CMD"])
	||	!strlen(info["NAME"]))
		return;

	mud = htonn( info["NAME"] );

	if (undefinedp(muds[mud])) return;

	if (undefinedp(mud_svc[mud])) mud_svc[mud] = ([]);

	if(!info["SUPPORTED"] && !info["NOTSUPPORTED"]) return; // mesed up packet

	if (info["CMD"] == "tcp") {
		cmd = info["PARAM"];

      // if udp is known then we know the whole status
      if (mud_svc[mud][cmd] & (SVC_UDP | SVC_NO_UDP))
	mud_svc[mud][cmd] |= SVC_KNOWN;

      if (info["SUPPORTED"])
	{
	  mud_svc[mud][cmd] |= SVC_TCP;
	  mud_svc[mud][cmd] &= ~SVC_NO_TCP;
	}
      else
	{
	  mud_svc[mud][cmd] |= SVC_NO_TCP;
	  mud_svc[mud][cmd] &= ~SVC_TCP;

	  // if they don't support something tcp, we check udp
	  if(!(mud_svc[mud][cmd] & SVC_KNOWN))
	    SUPPORT_Q->send_support_q(muds[mud]["HOSTADDRESS"],
				      muds[mud]["PORTUDP"], info["PARAM"]);
	}
    } // if (info["CMD"] == "tcp")
  else
    {
      cmd = info["CMD"];

      // if tcp is known then we know the whole status
      if (mud_svc[mud][cmd] & (SVC_TCP | SVC_NO_TCP))
	mud_svc[mud][cmd] |= SVC_KNOWN;

      if (info["SUPPORTED"])
	{
	  mud_svc[mud][cmd] |= SVC_UDP;
	  mud_svc[mud][cmd] &= ~SVC_NO_UDP;
	}
      else
	{
	  mud_svc[mud][cmd] |= SVC_NO_UDP;
	  mud_svc[mud][cmd] &= ~SVC_UDP;

	  // if they don't support something udp, we check tcp
	  if(!(mud_svc[mud][cmd] & SVC_KNOWN))
	    SUPPORT_Q->send_support_q(muds[mud]["HOSTADDRESS"],
				      muds[mud]["PORTUDP"], "tcp", info["CMD"]);
	}
    } // if (info["CMD"] == "tcp")

  return;
}

// This queries a mud just added to the database for its supported services
// What is queries for is dependant on config.h
private void
query_services(string mud, string address, string port, string tcp)
{
#ifdef PREF_MAIL
  if (!(mud_svc[mud]["mail"] & SVC_KNOWN))
    {
#if PREF_MAIL & SVC_TCP
      if (tcp == TCP_SOME && !(mud_svc[mud]["mail"] & (SVC_TCP | SVC_NO_TCP)))
	SUPPORT_Q->send_support_q(address, port, "tcp", "mail");
#elif PREF_MAIL & SVC_UDP
      if (!(mud_svc[mud]["mail"] & (SVC_UDP | SVC_NO_UDP)))
	SUPPORT_Q->send_support_q(address, port, "mail");
#endif
    }
#endif // PREF_MAIL

#ifdef PREF_FINGER
  if (!(mud_svc[mud]["finger"] & SVC_KNOWN))
    {
#if PREF_FINGER & SVC_TCP
      if (tcp == TCP_SOME && !(mud_svc[mud]["finger"] & (SVC_TCP | SVC_NO_TCP)))
	SUPPORT_Q->send_support_q(address, port, "tcp", "finger");
#endif
    }
#endif // PREF_FINGER

#ifdef PREF_TELL
  if (!(mud_svc[mud]["tell"] & SVC_KNOWN))
    {
#if PREF_TELL & SVC_TCP
      if (tcp == TCP_SOME && !(mud_svc[mud]["tell"] & (SVC_TCP | SVC_NO_TCP)))
	SUPPORT_Q->send_support_q(address, port, "tcp", "tell");
#endif
    }
#endif // PREF_TELL

  return;
}

/*----------------------------------------------------------------------------
 * Name server functions
 */
// this is used by the internet communication front ends.  It return
// flags representing whether a service is supported or not.
int query_service_method(string mud, string service)
{
  mud = htonn(mud);

  // do we know about the mud
  if (undefinedp(muds[mud]))
    return SVC_UNKNOWN;

  // if we have an entry, but no service entry, it is a static mud
  if (undefinedp(mud_svc[mud]))
    return SVC_TCP | SVC_NO_UDP | SVC_KNOWN;

  // if we have an entry for the mud, do we know what the service is ?
  if (undefinedp(mud_svc[mud][service]))
    {
      // if it is a standard service we try to find out
      if(member_array(service, STD_SERVICE) != -1)
	query_services(mud, muds[mud]["HOSTADDRESS"], muds[mud]["PORTUDP"],
		       muds[mud]["TCP"]);
      return SVC_UNKNOWN;
    }
  return mud_svc[mud][service];
}

mapping query_svc_entry(string mud)
{
//	if (ACCESS_CHECK(previous_object()))
	return mud_svc[mud];
}

string get_host_name(string name)
{
  name = htonn(name);

  if (name == mud_nname())
    return this_host["HOSTADDRESS"];
  if (undefinedp(muds[name]))
    return 0;
  return muds[name]["HOSTADDRESS"];
}

mapping query_mud_info(string name)
{
	name = htonn(name);
	if(name == mud_nname())
		return this_host + ([ "TIME" : ctime(time()) ]);
	return muds[name];
}

// this returns '1' if the mud is in the dns, or if it is us
int dns_mudp(string name)
{
	name = htonn( name );
	return undefinedp(mud_svc[name]) ? (name == mud_nname() ? 1 : 0) : 1;
}

// returns all the muds in the databases
mapping query_muds()
{
//	if (ACCESS_CHECK(previous_object()))
	return muds + ([ mud_nname():this_host + ([ "TIME":ctime(time()) ]) +
		(["USERS":sprintf("%d",sizeof(users())) ])
	]);
}

// returns the services mapping
mapping query_svc()
{
//	if (ACCESS_CHECK(previous_object()))
	return mud_svc;
}

// ----------------------------------------------------------------------------
// service sequencing functions
//
// this is a potential security nightmare, be careful what euid the object
// has when it calls the function
// ----------------------------------------------------------------------------

// register a function in the sequencer
varargs int idx_request(function f)
{
	if (file_name(previous_object())[0..strlen(AUX_PATH) - 1] != AUX_PATH)
		return 0;

	seq_ctr++;
	seq_entries[seq_ctr] = ({ geteuid(previous_object()), f, time() });

	return seq_ctr;
}

// call a function in the sequencer
void idx_callback(int idx, mixed param)
{
	mixed *entry;

	if (!ACCESS_CHECK(previous_object())) return;

  if (undefinedp(seq_entries[idx]))
      return;

  entry = seq_entries[idx];
  map_delete(seq_entries, idx);

  seteuid(entry[0]);
  (*entry[1]) (param);
  restore_euid();
}

// remove timed out entries
void sequence_clean_up()
{
  int i, now;
  int *indexes;

  if(find_call_out("sequence_clean_up") != -1)
    return;

  indexes = keys(seq_entries);
  now = time();
  i = sizeof(indexes);
  while (i--)
  if( now - seq_entries[indexes[i]][2] > SERVICE_TIMEOUT )
      {
	seteuid(seq_entries[indexes[i]][0]);
	(*seq_entries[indexes[i]][1]) (0);
	restore_euid();
   map_delete( seq_entries, indexes[i] );
      }
  call_out("sequence_clean_up", SEQ_CLEAN_INTERVAL);
}

/*----------------------------------------------------------------------------
 * general debugging stuff
 */
#ifdef DEBUG
mixed *
query_bootsrv()
{
	return bootsrv;
}

void dump_sequencer()
{
	printf("counter: %d\n\n%O\n", seq_ctr, seq_entries);
}

void dump_svc()
{
	printf("%O\n", mud_svc);
}

void dump_mud_keys()
{
	printf("%O\n", keys(muds));
}

void dump_svc_keys()
{
	printf("%O\n", keys(mud_svc));
}

void set_monitor(object ob)
{
	string euid;

/*
	euid = geteuid(previous_object());
	if (!euid || !member_group(euid, "admin") && !member_group(euid, "socket"))
		return;
*/
	monitor = ob;
}

object
query_monitor()
{
  return monitor;
}
#endif // DEBUG

/*----------------------------------------------------------------------------
 * some misc functions
 */
// Not really used yet
private void restore_euid()
{
	seteuid(ROOT_UID);
}

// Logging functions
// This one is for log entries from the auxiliaries
void
aux_log(string file, string entry)
{
  if(!ACCESS_CHECK(previous_object()))
    return;
  restore_euid();
  log_file(file, sprintf("%s: %s\n", ctime(time()), entry));
}

// This one is for warnings from the auxiliaries
void
aux_warning(string warning)
{
  if(!ACCESS_CHECK(previous_object()))
    return;
  log("dns_warning: "+warning);
}

// This is for internal use
private void
log(string entry)
{
  log_file(MY_LOG_FILE, sprintf("%s: %s\n", ctime(time()), entry));
}

// Used to find the ip number of the host we are on
void resolve_callback(string address, string my_ip, int key)
{
/*
  if(previous_object()) return;
*/
	this_host["HOSTADDRESS"] = my_ip;
}

// ----------------------------------------------------------------------------
// This starts us all off
// ----------------------------------------------------------------------------
void create()
{
	restore_euid();

	set("channel_id", "网路精灵");

	// find out which port we are on
	my_port = SRVC_PORT_UDP(mud_port());

	// initialise global mud info variables
	muds = allocate_mapping(MUDS_ALLOC);
	mud_svc = allocate_mapping(MUDS_ALLOC);

	// initialise the sequencing variables
	seq_ctr = 0;
	seq_entries = ([]);

	// set the bootserver default
	bootsrv = MUDLIST_DNS;
	bootsrv_retry = 0;

	// tell the mudlist_a daemon that we have cleared the database
	MUDLIST_A->clear_db_flag();

	// set up our own info
	this_host = ([
		"MUDNAME"	: CHINESE_MUD_NAME,	// add by ken@XAJH 1997-10-18
		"NAME"		: Mud_name(),
		"ALIAS"		: Mud_name(),
		"DRIVER"	: __VERSION__,		// add by ken@XAJH 1998-05-28
		"MUDLIB"	: MUDLIB_NAME,
		"VERSION"	: MUDLIB_VERSION,
		"HOST"		: query_host_name(),
		"HOSTADDRESS"	: 0,			// set in resolve_callback()
		"PORT"		: "" + mud_port(),
		"PORTUDP"	: "" + my_port,
		"ADMIN"		: MUD_ADMIN,
		"HTTP"		: MUD_WEB,
		"ENCODING"	: MUDLIB_ENCODING,	// add by ken@XAJH 1998-05-28
		"TIME"		: ctime(time()),
		"TCP"		: TCP_SERVICE_LEVEL,
		"USERS"		: sprintf("%d",sizeof(users())),
	]);

	resolve(query_host_name(), "resolve_callback");

	// initialise the udp socket, if successful start the database system
	if (startup_udp()) init_database();
	CHANNEL_D->do_channel(this_object(), "sys", "MUD 互联核心 DNS_MASTER 已经启动。 \n");
}

void remove()
{
	send_shutdown();
}