ObjFW  Diff

 * RFC 1035 doesn't specify if pointers to pointers are allowed, and if so how
 * many. Since it's unspecified, we have to assume that it might happen, but we
 * also want to limit it to avoid DoS. Limiting it to 16 levels of pointers and
 * immediately rejecting pointers to itself seems like a fair balance.
 */
#define MAX_ALLOWED_POINTERS 16




#if defined(OF_HAIKU)
# define HOSTS_PATH @"/system/settings/network/hosts"
# define RESOLV_CONF_PATH @"/system/settings/network/resolv.conf"
#elif defined(OF_MORPHOS)
# define HOSTS_PATH @"ENV:sys/net/hosts"
# define RESOLV_CONF_PATH @"ENV:sys/net/resolv.conf"
#elif defined(OF_AMIGAOS4)

@public
	OFString *_host, *_domainName;
	of_dns_resource_record_class_t _recordClass;
	of_dns_resource_record_type_t _recordType;
	OFNumber *_ID;
	OFArray OF_GENERIC(OFString *) *_nameServers, *_searchDomains;
	size_t _nameServersIndex, _searchDomainsIndex;
	of_time_interval_t _timeout;
	unsigned int _maxRetries;
	size_t _attempt;
	id _target;
	SEL _selector;
	id _context;
	OFData *_queryData;
	OFTimer *_cancelTimer;
}

- (instancetype)initWithHost: (OFString *)host
		  domainName: (OFString *)domainName
		 recordClass: (of_dns_resource_record_class_t)recordClass
		  recordType: (of_dns_resource_record_type_t)recordType
			  ID: (OFNumber *)ID
		 nameServers: (OFArray OF_GENERIC(OFString *) *)nameServers
	       searchDomains: (OFArray OF_GENERIC(OFString *) *)searchDomains
		     timeout: (of_time_interval_t)timeout
		  maxRetries: (unsigned int)maxRetries
		      target: (id)target
		    selector: (SEL)selector
		     context: (id)context;
@end

@interface OFDNSResolver ()
- (void)of_setDefaults;
- (void)of_parseConfig;
#ifdef OF_HAVE_FILES
- (void)of_parseHosts: (OFString *)path;
# ifndef OF_WINDOWS
- (void)of_parseResolvConf: (OFString *)path;
- (void)of_parseResolvConfOption: (OFString *)option;
# endif

- (instancetype)initWithHost: (OFString *)host
		  domainName: (OFString *)domainName
		 recordClass: (of_dns_resource_record_class_t)recordClass
		  recordType: (of_dns_resource_record_type_t)recordType
			  ID: (OFNumber *)ID
		 nameServers: (OFArray OF_GENERIC(OFString *) *)nameServers
	       searchDomains: (OFArray OF_GENERIC(OFString *) *)searchDomains
		     timeout: (of_time_interval_t)timeout
		  maxRetries: (unsigned int)maxRetries
		      target: (id)target
		    selector: (SEL)selector
		     context: (id)context
{
	self = [super init];

	@try {
		void *pool = objc_autoreleasePoolPush();
		OFMutableData *queryData;
		uint16_t tmp;

		_host = [host copy];
		_domainName = [domainName copy];
		_recordClass = recordClass;
		_recordType = recordType;
		_ID = [ID retain];
		_nameServers = [nameServers copy];
		_searchDomains = [searchDomains copy];
		_timeout = timeout;
		_maxRetries = maxRetries;
		_target = [target retain];
		_selector = selector;
		_context = [context retain];

		queryData = [OFMutableData dataWithCapacity: 512];

		/* Header */

	[super dealloc];
}
@end

@implementation OFDNSResolver
@synthesize staticHosts = _staticHosts, nameServers = _nameServers;
@synthesize localDomain = _localDomain, searchDomains = _searchDomains;
@synthesize timeout = _timeout, maxRetries = _maxRetries;
@synthesize minNumberOfDotsInAbsoluteName = _minNumberOfDotsInAbsoluteName;
@synthesize usesTCP = _usesTCP, configReloadInterval = _configReloadInterval;

+ (instancetype)resolver
{
	return [[[self alloc] init] autorelease];
}

	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)of_setDefaults
{
	_timeout = 2;
	_maxRetries = 3;
	_minNumberOfDotsInAbsoluteName = 1;
	_usesTCP = false;
	_configReloadInterval = 2;
}

- (void)of_parseConfig
{
	void *pool = objc_autoreleasePoolPush();
#ifdef OF_WINDOWS
	OFString *path;
#endif





#if defined(OF_WINDOWS)
# ifdef OF_HAVE_FILES
	path = [[OFWindowsRegistryKey localMachineKey]
	    stringForValue: @"DataBasePath"
		subKeyPath: @"SYSTEM\\CurrentControlSet\\Services\\"
			    @"Tcpip\\Parameters"];
	path = [path stringByAppendingPathComponent: @"hosts"];

	[_localDomain release];
	_localDomain = nil;

	[_searchDomains release];
	_searchDomains = nil;


	[self of_setDefaults];


	[_lastConfigReload release];
	_lastConfigReload = nil;

	[self of_parseConfig];
}

	    initWithHost: host
	      domainName: domainName
	     recordClass: recordClass
	      recordType: recordType
		      ID: ID
	     nameServers: _nameServers
	   searchDomains: _searchDomains
		 timeout: _timeout
	      maxRetries: _maxRetries
		  target: target
		selector: selector
		 context: context] autorelease];
	[_queries setObject: query
		     forKey: ID];

	[self of_sendQuery: query];

	objc_autoreleasePoolPop(pool);
}

- (void)of_sendQuery: (OFDNSResolverQuery *)query
{
	of_socket_address_t address;
	OFUDPSocket *sock;

	[query->_cancelTimer invalidate];
	[query->_cancelTimer release];
	query->_cancelTimer = nil;
	query->_cancelTimer = [[OFTimer
	    scheduledTimerWithTimeInterval: query->_timeout
				    target: self
				  selector: @selector(of_queryWithIDTimedOut:)
				    object: query
				   repeats: false] retain];

	address = of_socket_address_parse_ip(
	    [query->_nameServers objectAtIndex: query->_nameServersIndex], 53);

	if (query->_nameServersIndex + 1 < [query->_nameServers count]) {
		query->_nameServersIndex++;
		[self of_sendQuery: query];
		return;
	}

	if (query->_attempt < query->_maxRetries) {
		query->_attempt++;
		query->_nameServersIndex = 0;
		[self of_sendQuery: query];
		return;
	}

	query = [[query retain] autorelease];