ObjFW  Artifact [49ac97ac70]

Artifact 49ac97ac70bee91ae8fbd317baec537d5d8a637039d236ed4b9c7bbf477a38c5:

  • File src/OFZIPArchiveEntry.m — part of check-in [be628bbb84] at 2013-11-06 20:58:10 on branch trunk — OFZIPArchive: Do not sort -[entries].

    While sorting -[entries] reduces hard disk seeks, it allows a denial of
    service by creating an archive with a huge central directory without
    actual files. As usually the order in the central directory matches the
    order of the actual files, this minor speed increase is not worth the
    attack vector. (user: js, size: 6241) [annotate] [blame] [check-ins using]


/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013
 *   Jonathan Schleifer <js@webkeks.org>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *
 * Alternatively, it may be distributed under the terms of the GNU General
 * Public License, either version 2 or 3, which can be found in the file
 * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
 * file.
 */

#include "config.h"

#import "OFZIPArchiveEntry.h"
#import "OFZIPArchiveEntry+Private.h"
#import "OFString.h"
#import "OFDataArray.h"
#import "OFFile.h"
#import "OFDate.h"

#import "autorelease.h"
#import "macros.h"

#import "OFInvalidArgumentException.h"
#import "OFInvalidFormatException.h"

extern void of_zip_archive_find_extra_field(OFDataArray*, uint16_t, uint8_t**,
    uint16_t*);
extern uint32_t of_zip_archive_read_field32(uint8_t**, uint16_t*);
extern uint64_t of_zip_archive_read_field64(uint8_t**, uint16_t*);

@implementation OFZIPArchiveEntry
- (instancetype)OF_initWithFile: (OFFile*)file
{
	self = [super init];

	@try {
		void *pool = objc_autoreleasePoolPush();
		uint16_t fileNameLength, extraFieldLength, fileCommentLength;
		of_string_encoding_t encoding;
		uint8_t *ZIP64 = NULL;
		uint16_t ZIP64Size;

		if ([file readLittleEndianInt32] != 0x02014B50)
			@throw [OFInvalidFormatException exception];

		_madeWithVersion = [file readLittleEndianInt16];
		_minVersion = [file readLittleEndianInt16];
		_generalPurposeBitFlag = [file readLittleEndianInt16];
		_compressionMethod = [file readLittleEndianInt16];
		_lastModifiedFileTime = [file readLittleEndianInt16];
		_lastModifiedFileDate = [file readLittleEndianInt16];
		_CRC32 = [file readLittleEndianInt32];
		_compressedSize = [file readLittleEndianInt32];
		_uncompressedSize = [file readLittleEndianInt32];
		fileNameLength = [file readLittleEndianInt16];
		extraFieldLength = [file readLittleEndianInt16];
		fileCommentLength = [file readLittleEndianInt16];
		_startDiskNumber = [file readLittleEndianInt16];
		_internalAttributes = [file readLittleEndianInt16];
		_externalAttributes = [file readLittleEndianInt32];
		_localFileHeaderOffset = [file readLittleEndianInt32];

		encoding = (_generalPurposeBitFlag & (1 << 11)
		    ? OF_STRING_ENCODING_UTF_8
		    : OF_STRING_ENCODING_CODEPAGE_437);

		_fileName = [[file readStringWithLength: fileNameLength
					       encoding: encoding] copy];
		_extraField = [[file
		    readDataArrayWithCount: extraFieldLength] retain];
		_fileComment = [[file readStringWithLength: fileCommentLength
						  encoding: encoding] copy];

		of_zip_archive_find_extra_field(_extraField, 0x0001,
		    &ZIP64, &ZIP64Size);

		if (ZIP64 != NULL) {
			if (_uncompressedSize == 0xFFFFFFFF)
				_uncompressedSize = of_zip_archive_read_field64(
				    &ZIP64, &ZIP64Size);
			if (_compressedSize == 0xFFFFFFFF)
				_compressedSize = of_zip_archive_read_field64(
				    &ZIP64, &ZIP64Size);
			if (_localFileHeaderOffset == 0xFFFFFFFF)
				_localFileHeaderOffset =
				    of_zip_archive_read_field64(&ZIP64,
				    &ZIP64Size);
			if (_startDiskNumber == 0xFFFF)
				_startDiskNumber = of_zip_archive_read_field32(
				    &ZIP64, &ZIP64Size);

			if (ZIP64Size > 0)
				@throw [OFInvalidFormatException exception];
		}

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

	return self;
}

- (void)dealloc
{
	[_fileName release];
	[_extraField release];
	[_fileComment release];

	[super dealloc];
}

- (OFString*)fileName
{
	OF_GETTER(_fileName, true)
}

- (OFString*)fileComment
{
	OF_GETTER(_fileComment, true)
}

- (uint64_t)compressedSize
{
	return _compressedSize;
}

- (uint64_t)uncompressedSize
{
	return _uncompressedSize;
}

- (OFDate*)modificationDate
{
	void *pool = objc_autoreleasePoolPush();
	uint_fast16_t year = ((_lastModifiedFileDate & 0xFE00) >> 9) + 1980;
	uint_fast8_t month = (_lastModifiedFileDate & 0x1E0) >> 5;
	uint_fast8_t day = (_lastModifiedFileDate & 0x1F);
	uint_fast8_t hour = (_lastModifiedFileTime & 0xF800) >> 11;
	uint_fast8_t minute = (_lastModifiedFileTime & 0x7E0) >> 5;
	uint_fast8_t second = (_lastModifiedFileTime & 0x1F) << 1;
	OFDate *date;
	OFString *dateString;

	dateString = [OFString
	    stringWithFormat: @"%04u-%02u-%02u %02u:%02u:%02u",
			      year, month, day, hour, minute, second];

	date = [[OFDate alloc] initWithLocalDateString: dateString
						format: @"%Y-%m-%d %H:%M:%S"];

	objc_autoreleasePoolPop(pool);

	return [date autorelease];
}

- (uint32_t)CRC32
{
	return _CRC32;
}

- (OFDataArray*)extraField
{
	return [[_extraField copy] autorelease];
}

- (OFString*)description
{
	void *pool = objc_autoreleasePoolPush();
	OFDate *modificationDate = [self modificationDate];
	OFString *ret;

	ret = [[OFString alloc] initWithFormat: @"<%@: %p\n"
	    @"\tFile name = %@\n"
	    @"\tFile comment = %@\n"
	    @"\tGeneral purpose bit flag = %u\n"
	    @"\tCompression method = %u\n"
	    @"\tCompressed size = %ju\n"
	    @"\tUncompressed size = %ju\n"
	    @"\tModification date = %@\n"
	    @"\tCRC32 = %" @PRIu32 @"\n"
	    @"\tExtra field = %@\n"
	    @"}",
	    [self class], self, _fileName, _fileComment, _generalPurposeBitFlag,
	    _compressionMethod, (intmax_t)_compressedSize,
	    (intmax_t)_uncompressedSize, modificationDate, _CRC32, _extraField];

	objc_autoreleasePoolPop(pool);

	return [ret autorelease];
}

- (uint16_t)OF_madeWithVersion
{
	return _madeWithVersion;
}

- (uint16_t)OF_minVersion
{
	return _minVersion;
}

- (uint16_t)OF_generalPurposeBitFlag
{
	return _generalPurposeBitFlag;
}

- (uint16_t)OF_compressionMethod
{
	return _compressionMethod;
}

- (uint16_t)OF_lastModifiedFileTime
{
	return _lastModifiedFileTime;
}

- (uint16_t)OF_lastModifiedFileDate
{
	return _lastModifiedFileDate;
}

- (OFDataArray*)OF_extraFieldNoCopy
{
	OF_GETTER(_extraField, true)
}

- (uint16_t)OF_startDiskNumber
{
	return _startDiskNumber;
}

- (uint16_t)OF_internalAttributes
{
	return _internalAttributes;
}

- (uint32_t)OF_externalAttributes
{
	return _externalAttributes;
}

- (uint64_t)OF_localFileHeaderOffset
{
	return _localFileHeaderOffset;
}
@end