ObjFW  Artifact [85d6f8f249]

Artifact 85d6f8f249d08bfdb7b8c2189c9e987bacb78d80ea1f522a7c30442078a1ff52:

• File src/OFZIPArchive.m — part of check-in [8d2a5052fd] at 2014-01-25 17:39:13 on branch trunk — Generalize stream / socket related exceptions

  This is in preparation for adding UDP sockets, as UDP sockets and TCP
  sockets have no common superclass, as one is stream-oriented while the
  other is packet-oriented.

  Read and write exceptions are for any object now, as they are useful for
  a lot more than just for streams, while the others (bind, listen, etc.)
  are for any socket now (the type is id in this case, though, as there is
  no common superclass). (user: js, size: 13930) [annotate] [blame] [check-ins using]

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014
 *   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 "OFZIPArchive.h"
#import "OFZIPArchiveEntry.h"
#import "OFZIPArchiveEntry+Private.h"
#import "OFDataArray.h"
#import "OFArray.h"
#import "OFDictionary.h"
#import "OFFile.h"
#import "OFDeflateStream.h"
#import "OFDeflate64Stream.h"

#import "OFChecksumFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFInvalidFormatException.h"
#import "OFNotImplementedException.h"
#import "OFOpenFileFailedException.h"
#import "OFOutOfRangeException.h"
#import "OFReadFailedException.h"
#import "OFSeekFailedException.h"
#import "OFUnsupportedVersionException.h"

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

#define CRC32_MAGIC 0xEDB88320

/*
 * FIXME: Current limitations:
 *  - Split archives are not supported.
 *  - Write support is missing.
 *  - The ZIP has to be a file on the local file system.
 *  - Encrypted files cannot be read.
 */

@interface OFZIPArchive (OF_PRIVATE_CATEGORY)
- (void)OF_readZIPInfo;
- (void)OF_readEntries;
@end

@interface OFZIPArchive_LocalFileHeader: OFObject
{
@public
	uint16_t _minVersion, _generalPurposeBitFlag, _compressionMethod;
	uint16_t _lastModifiedFileTime, _lastModifiedFileDate;
	uint32_t _CRC32;
	uint64_t _compressedSize, _uncompressedSize;
	OFString *_fileName;
	OFDataArray *_extraField;
}

- initWithFile: (OFFile*)file;
- (bool)matchesEntry: (OFZIPArchiveEntry*)entry;
@end

@interface OFZIPArchive_FileStream: OFStream
{
	OFStream *_stream;
	OFFile *_file;
	OFZIPArchive_LocalFileHeader *_localFileHeader;
	bool _hasDataDescriptor;
	uint64_t _size;
	uint32_t _CRC32;
	bool _atEndOfStream;
}

- initWithArchiveFile: (OFString*)path
	       offset: (off_t)offset
      localFileHeader: (OFZIPArchive_LocalFileHeader*)localFileHeader;
@end

void
of_zip_archive_find_extra_field(OFDataArray *extraField, uint16_t tag,
    uint8_t **data, uint16_t *size)
{
	uint8_t *bytes;
	size_t i, count;

	bytes = [extraField items];
	count = [extraField count];

	for (i = 0; i < count;) {
		uint16_t currentTag, currentSize;

		if (i + 3 >= count)
			@throw [OFInvalidFormatException exception];

		currentTag = (bytes[i + 1] << 8) | bytes[i];
		currentSize = (bytes[i + 3] << 8) | bytes[i + 2];

		if (i + 3 + currentSize >= count)
			@throw [OFInvalidFormatException exception];

		if (currentTag == tag) {
			*data = bytes + i + 4;
			*size = currentSize;
			return;
		}

		i += 4 + currentSize;
	}

	*data = NULL;
	*size = 0;
}

uint32_t
of_zip_archive_read_field32(uint8_t **data, uint16_t *size)
{
	uint32_t field = 0;
	uint_fast8_t i;

	if (*size < 4)
		@throw [OFInvalidFormatException exception];

	for (i = 0; i < 4; i++)
		field |= (uint32_t)(*data)[i] << (i * 8);

	*data += 4;
	*size -= 4;

	return field;
}

uint64_t
of_zip_archive_read_field64(uint8_t **data, uint16_t *size)
{
	uint64_t field = 0;
	uint_fast8_t i;

	if (*size < 8)
		@throw [OFInvalidFormatException exception];

	for (i = 0; i < 8; i++)
		field |= (uint64_t)(*data)[i] << (i * 8);

	*data += 8;
	*size -= 8;

	return field;
}

static uint32_t
crc32(uint32_t crc, uint8_t *bytes, size_t length)
{
	size_t i;

	for (i = 0; i < length; i++) {
		uint_fast8_t j;

		crc ^= bytes[i];

		for (j = 0; j < 8; j++)
			crc = (crc >> 1) ^ (CRC32_MAGIC & (~(crc & 1) + 1));
	}

	return crc;
}

@implementation OFZIPArchive
+ (instancetype)archiveWithPath: (OFString*)path
{
	return [[[self alloc] initWithPath: path] autorelease];
}

- init
{
	OF_INVALID_INIT_METHOD
}

- initWithPath: (OFString*)path
{
	self = [super init];

	@try {
		_file = [[OFFile alloc] initWithPath: path
						mode: @"rb"];
		_path = [path copy];

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

	return self;
}

- (void)dealloc
{
	[_file release];
	[_path release];
	[_archiveComment release];
	[_entries release];
	[_pathToEntryMap release];

	[super dealloc];
}

- (void)OF_readZIPInfo
{
	void *pool = objc_autoreleasePoolPush();
	uint16_t commentLength;
	off_t offset = -22;
	bool valid = false;

	do {
		@try {
			[_file seekToOffset: offset
				     whence: SEEK_END];
		} @catch (OFSeekFailedException *e) {
			if ([e errNo] == EINVAL)
				@throw [OFInvalidFormatException exception];

			@throw e;
		}

		if ([_file readLittleEndianInt32] == 0x06054B50) {
			valid = true;
			break;
		}
	} while (--offset >= -65557);

	if (!valid)
		@throw [OFInvalidFormatException exception];

	_diskNumber = [_file readLittleEndianInt16],
	_centralDirectoryDisk = [_file readLittleEndianInt16];
	_centralDirectoryEntriesInDisk = [_file readLittleEndianInt16];
	_centralDirectoryEntries = [_file readLittleEndianInt16];
	_centralDirectorySize = [_file readLittleEndianInt32];
	_centralDirectoryOffset = [_file readLittleEndianInt32];

	commentLength = [_file readLittleEndianInt16];
	_archiveComment = [[_file
	    readStringWithLength: commentLength
			encoding: OF_STRING_ENCODING_CODEPAGE_437] copy];

	if (_diskNumber == 0xFFFF ||
	    _centralDirectoryDisk == 0xFFFF ||
	    _centralDirectoryEntriesInDisk == 0xFFFF ||
	    _centralDirectoryEntries == 0xFFFF ||
	    _centralDirectorySize == 0xFFFFFFFF ||
	    _centralDirectoryOffset == 0xFFFFFFFF) {
		uint64_t offset64, size;

		[_file seekToOffset: offset - 20
			     whence: SEEK_END];

		if ([_file readLittleEndianInt32] != 0x07064B50) {
			objc_autoreleasePoolPop(pool);
			return;
		}

		/*
		 * FIXME: Handle number of the disk containing ZIP64 end of
		 * central directory record.
		 */
		[_file readLittleEndianInt32];
		offset64 = [_file readLittleEndianInt64];

		if ((off_t)offset64 != offset64)
			@throw [OFOutOfRangeException exception];

		[_file seekToOffset: (off_t)offset64
			     whence: SEEK_SET];

		if ([_file readLittleEndianInt32] != 0x06064B50)
			@throw [OFInvalidFormatException exception];

		size = [_file readLittleEndianInt64];
		if (size < 44)
			@throw [OFInvalidFormatException exception];

		/* version made by */
		[_file readLittleEndianInt16];
		/* version needed to extract */
		[_file readLittleEndianInt16];

		_diskNumber = [_file readLittleEndianInt32];
		_centralDirectoryDisk = [_file readLittleEndianInt32];
		_centralDirectoryEntriesInDisk = [_file readLittleEndianInt64];
		_centralDirectoryEntries = [_file readLittleEndianInt64];
		_centralDirectorySize = [_file readLittleEndianInt64];
		_centralDirectoryOffset = [_file readLittleEndianInt64];

		if ((off_t)_centralDirectoryOffset != _centralDirectoryOffset)
			@throw [OFOutOfRangeException exception];
	}

	objc_autoreleasePoolPop(pool);
}

- (void)OF_readEntries
{
	void *pool = objc_autoreleasePoolPush();
	size_t i;

	if ((off_t)_centralDirectoryOffset != _centralDirectoryOffset)
		@throw [OFOutOfRangeException exception];

	[_file seekToOffset: (off_t)_centralDirectoryOffset
		     whence: SEEK_SET];

	_entries = [[OFMutableArray alloc] init];
	_pathToEntryMap = [[OFMutableDictionary alloc] init];

	for (i = 0; i < _centralDirectoryEntries; i++) {
		OFZIPArchiveEntry *entry = [[[OFZIPArchiveEntry alloc]
		    OF_initWithFile: _file] autorelease];

		if ([_pathToEntryMap objectForKey: [entry fileName]] != nil)
			@throw [OFInvalidFormatException exception];

		[_entries addObject: entry];
		[_pathToEntryMap setObject: entry
				    forKey: [entry fileName]];
	}

	[_entries makeImmutable];
	[_pathToEntryMap makeImmutable];

	objc_autoreleasePoolPop(pool);
}

- (OFArray*)entries
{
	OF_GETTER(_entries, true)
}

- (OFString*)archiveComment
{
	OF_GETTER(_archiveComment, true)
}

- (OFStream*)streamForReadingFile: (OFString*)path
{
	OFStream *ret;
	void *pool = objc_autoreleasePoolPush();
	OFZIPArchiveEntry *entry = [_pathToEntryMap objectForKey: path];
	OFZIPArchive_LocalFileHeader *localFileHeader;
	uint64_t offset;

	if (entry == nil) {
		errno = ENOENT;
		@throw [OFOpenFileFailedException exceptionWithPath: path
							       mode: @"rb"];
	}

	offset = [entry OF_localFileHeaderOffset];
	if ((off_t)offset != offset)
		@throw [OFOutOfRangeException exception];

	[_file seekToOffset: (off_t)offset
		     whence: SEEK_SET];
	localFileHeader = [[[OFZIPArchive_LocalFileHeader alloc]
	    initWithFile: _file] autorelease];

	if (![localFileHeader matchesEntry: entry])
		@throw [OFInvalidFormatException exception];

	if ((localFileHeader->_minVersion & 0xFF) > 45) {
		OFString *version = [OFString stringWithFormat: @"%u.%u",
		    (localFileHeader->_minVersion & 0xFF) / 10,
		    (localFileHeader->_minVersion & 0xFF) % 10];

		@throw [OFUnsupportedVersionException
		    exceptionWithVersion: version];
	}

	ret = [[OFZIPArchive_FileStream alloc]
	    initWithArchiveFile: _path
			 offset: [_file seekToOffset: 0
					      whence: SEEK_CUR]
	        localFileHeader: localFileHeader];

	objc_autoreleasePoolPop(pool);

	return [ret autorelease];
}
@end

@implementation OFZIPArchive_LocalFileHeader
- initWithFile: (OFFile*)file
{
	self = [super init];

	@try {
		uint16_t fileNameLength, extraFieldLength;
		of_string_encoding_t encoding;
		uint8_t *ZIP64;
		uint16_t ZIP64Size;

		if ([file readLittleEndianInt32] != 0x04034B50)
			@throw [OFInvalidFormatException exception];

		_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];
		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];

		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 (ZIP64Size > 0)
				@throw [OFInvalidFormatException exception];
		}
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

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

	[super dealloc];
}

- (bool)matchesEntry: (OFZIPArchiveEntry*)entry
{
	if (_minVersion != [entry OF_minVersion] ||
	    _generalPurposeBitFlag != [entry OF_generalPurposeBitFlag] ||
	    _compressionMethod != [entry OF_compressionMethod] ||
	    _lastModifiedFileTime != [entry OF_lastModifiedFileTime] ||
	    _lastModifiedFileDate != [entry OF_lastModifiedFileDate])
		return false;

	if (!(_generalPurposeBitFlag & (1 << 3)))
		if (_CRC32 != [entry CRC32] ||
		    _compressedSize != [entry compressedSize] ||
		    _uncompressedSize != [entry uncompressedSize])
			return false;

	if (![_fileName isEqual: [entry fileName]])
		return false;

	return true;
}
@end

@implementation OFZIPArchive_FileStream
- initWithArchiveFile: (OFString*)path
	       offset: (off_t)offset
      localFileHeader: (OFZIPArchive_LocalFileHeader*)localFileHeader
{
	self = [super init];

	@try {
		_file = [[OFFile alloc] initWithPath: path
						mode: @"rb"];
		[_file seekToOffset: offset
			     whence: SEEK_SET];

		switch (localFileHeader->_compressionMethod) {
		case 0: /* No compression */
			_stream = [_file retain];
			break;
		case 8: /* Deflate */
			_stream = [[OFDeflateStream alloc]
			    initWithStream: _file];
			break;
		case 9: /* Deflate64 */
			_stream = [[OFDeflate64Stream alloc]
			    initWithStream: _file];
			break;
		default:
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
		}

		_localFileHeader = [localFileHeader retain];
		_hasDataDescriptor = (localFileHeader->_generalPurposeBitFlag &
		    (1 << 3));
		_size = localFileHeader->_uncompressedSize;
		_CRC32 = ~0;
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_stream release];
	[_file release];
	[_localFileHeader release];

	[super dealloc];
}

- (bool)lowlevelIsAtEndOfStream
{
	return _atEndOfStream;
}

- (size_t)lowlevelReadIntoBuffer: (void*)buffer
			  length: (size_t)length
{
	size_t min, ret;

	if (_atEndOfStream)
		@throw [OFReadFailedException exceptionWithObject: self
						  requestedLength: length];

	if (_hasDataDescriptor) {
		if ([_stream isAtEndOfStream]) {
			uint32_t CRC32;

			_atEndOfStream = true;

			CRC32 = [_file readLittleEndianInt32];
			if (CRC32 == 0x08074B50)
				CRC32 = [_file readLittleEndianInt32];

			if (~_CRC32 != CRC32)
				@throw [OFChecksumFailedException exception];

			/*
			 * FIXME: Check (un)compressed length!
			 * (Note: Both are 64 bit if the entry uses ZIP64!)
			 */

			return 0;
		}

		ret = [_stream readIntoBuffer: buffer
				       length: length];
	} else {
		if (_size == 0) {
			_atEndOfStream = true;

			if (~_CRC32 != _localFileHeader->_CRC32)
				@throw [OFChecksumFailedException exception];

			return 0;
		}

		min = (length < _size ? length : (size_t)_size);
		ret = [_stream readIntoBuffer: buffer
				       length: min];
		_size -= ret;
	}

	_CRC32 = crc32(_CRC32, buffer, ret);

	return ret;
}
@end