ObjFW  Check-in [bd5e1e2014]

 * TODO:
 *
 *  - Timeouts
 *  - Resolve with each search domain
 *  - Iterate through name servers
 *  - IPv6 for talking to the name servers
 *  - Fallback to TCP
 *  - More record types
 */

@interface OFDNSResolver_context: OFObject
{
	OFString *_host;
	OFArray OF_GENERIC(OFString *) *_nameServers, *_searchDomains;
	size_t _nameServersIndex, _searchDomainsIndex;

	*idx = i;

	return [components componentsJoinedByString: @"."];
}

static OFString *
parseAAAAData(const unsigned char *buffer)
{
	OFMutableString *data = [OFMutableString string];
	int_fast8_t zerosStart = -1, maxZerosStart = -1;
	uint_fast8_t zerosCount = 0, maxZerosCount = 0;
	bool first = true;

	for (uint_fast8_t i = 0; i < 16; i += 2) {

	}

	[data makeImmutable];

	return data;
}

static OF_KINDOF(OFDNSResourceRecord *)

createResourceRecord(OFString *name, of_dns_resource_record_class_t recordClass,
    of_dns_resource_record_type_t recordType, uint32_t TTL,
    const unsigned char *buffer, size_t length, size_t i, size_t dataLength)
{
	Class class;
	id data;

	if (recordClass == OF_DNS_RESOURCE_RECORD_CLASS_IN) {
		size_t j;

		switch (recordType) {
		case OF_DNS_RESOURCE_RECORD_TYPE_A:
			if (dataLength != 4)
				@throw [OFInvalidServerReplyException
				    exception];

			class = [OFADNSResourceRecord class];
			data = [OFString stringWithFormat:
			    @"%u.%u.%u.%u",
			    buffer[i], buffer[i + 1],
			    buffer[i + 2], buffer[i + 3]];
			break;
		case OF_DNS_RESOURCE_RECORD_TYPE_CNAME:
			j = i;

			class = [OFCNAMEDNSResourceRecord class];
			data = parseName(buffer, length, &j,
			    ALLOWED_POINTER_LEVELS);

			if (j != i + dataLength)
				@throw [OFInvalidServerReplyException
				    exception];

			break;
		case OF_DNS_RESOURCE_RECORD_TYPE_AAAA:
			if (dataLength != 16)
				@throw [OFInvalidServerReplyException
				    exception];

			class = [OFAAAADNSResourceRecord class];
			data = parseAAAAData(&buffer[i]);
			break;
		default:
			class = [OFDNSResourceRecord class];
			data = [OFData dataWithItems: &buffer[i]
					       count: dataLength];
			break;
		}
	} else {
		class = [OFDNSResourceRecord class];
		data = [OFData dataWithItems: &buffer[i]
				       count: dataLength];
	}

	return [[[class alloc] initWithName: name
				recordClass: recordClass
				 recordType: recordType
				       data: data
					TTL: TTL] autorelease];
}

@implementation OFDNSResolver_context
@synthesize host = _host, nameServers = _nameServers;
@synthesize searchDomains = _searchDomains;
@synthesize nameServersIndex = _nameServersIndex;
@synthesize searchDomainsIndex = _searchDomainsIndex, queryData = _queryData;

		for (uint_fast16_t j = 0; j < numAnswers; j++) {
			OFString *name = parseName(buffer, length, &i,
			    ALLOWED_POINTER_LEVELS);
			of_dns_resource_record_class_t recordClass;
			of_dns_resource_record_type_t recordType;
			uint32_t TTL;
			uint16_t dataLength;

			OFDNSResourceRecord *record;

			if (i + 10 > length)
				@throw [OFTruncatedDataException exception];

			recordType = (buffer[i] << 16) | buffer[i + 1];
			recordClass = (buffer[i + 2] << 16) | buffer[i + 3];
			TTL = (buffer[i + 4] << 24) | (buffer[i + 5] << 16) |
			    (buffer[i + 6] << 8) | buffer[i + 7];
			dataLength = (buffer[i + 8] << 16) | buffer[i + 9];

			i += 10;

			if (i + dataLength > length)
				@throw [OFTruncatedDataException exception];

			record = createResourceRecord(name, recordClass,
			    recordType, TTL, buffer, length, i, dataLength);

			i += dataLength;








			[answers addObject: record];
		}
	} @catch (id e) {
		callback(target, selector, nil,
		    [DNSResolverContext userContext], e);
		return false;
	}

	/*! All types. Only for queries. */
	OF_DNS_RESOURCE_RECORD_TYPE_ALL	  = 255,
} of_dns_resource_record_type_t;

/*!
 * @class OFDNSResourceRecord OFDNSResourceRecord.h ObjFW/OFDNSResourceRecord.h
 *
 * @brief A class representing a DNS resource record.
 */
@interface OFDNSResourceRecord: OFObject
{
	OFString *_name;
	of_dns_resource_record_class_t _recordClass;
	of_dns_resource_record_type_t _recordType;
	id _data;

/*!
 * @brief The resource record type code.
 */
@property (readonly, nonatomic) of_dns_resource_record_type_t recordType;

/*!
 * The class and type-dependent data of the resource.




 */
@property (readonly, nonatomic) id data;

/*!
 * @brief The number of seconds after which the resource record should be
 *	  discarded from the cache.
 */
@property (readonly, nonatomic) uint32_t TTL;

- (instancetype)initWithName: (OFString *)name
		 recordClass: (of_dns_resource_record_class_t)recordClass
		  recordType: (of_dns_resource_record_type_t)recordType
			data: (id)data
			 TTL: (uint32_t)TTL OF_DESIGNATED_INITIALIZER;
@end

/*!
 * @class OFADNSResourceRecord OFDNSResourceRecord.h ObjFW/OFDNSResourceRecord.h
 *
 * @brief A class representing an A DNS resource record.
 */
@interface OFADNSResourceRecord: OFDNSResourceRecord
/*!
 * A string with the IP address.
 */
@property (readonly, nonatomic) OFString *data;
@end

/*!
 * @class OFAAAADNSResourceRecord \
 *	  OFDNSResourceRecord.h ObjFW/OFDNSResourceRecord.h
 *
 * @brief A class represenging a DNS resource record.
 */
@interface OFAAAADNSResourceRecord: OFDNSResourceRecord
/*!
 * A string with the IP address.
 */
@property (readonly, nonatomic) OFString *data;
@end

/*!
 * @class OFCNAMEDNSResourceRecord \
 *	  OFDNSResourceRecord.h ObjFW/OFDNSResourceRecord.h
 *
 * @brief A class representing a CNAME DNS resource record.
 */
@interface OFCNAMEDNSResourceRecord: OFDNSResourceRecord
/*!
 * A string with the alias.
 */
@property (readonly, nonatomic) OFString *data;
@end

#ifdef __cplusplus
extern "C" {
#endif
extern OFString *_Nonnull of_dns_resource_record_class_to_string(
    of_dns_resource_record_class_t recordClass);
extern OFString *_Nonnull of_dns_resource_record_type_to_string(
    of_dns_resource_record_type_t recordType);
#ifdef __cplusplus
}
#endif

OF_ASSUME_NONNULL_END

	    @"\tData = %@\n"
	    @"\tTTL = %" PRIu32 "\n"
	    @">",
	    _name, of_dns_resource_record_class_to_string(_recordClass),
	    of_dns_resource_record_type_to_string(_recordType), _data, _TTL];
}
@end

@implementation OFADNSResourceRecord
- (OFString *)data
{
	return _data;
}
@end

@implementation OFAAAADNSResourceRecord
- (OFString *)data
{
	return _data;
}
@end

@implementation OFCNAMEDNSResourceRecord
- (OFString *)data
{
	return _data;
}
@end