/*
* Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im>
*
* 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 "OFASN1BitString.h"
#import "OFData.h"
#import "OFString.h"
#import "OFInvalidArgumentException.h"
#import "OFInvalidFormatException.h"
#import "OFOutOfRangeException.h"
@implementation OFASN1BitString
@synthesize bitStringValue = _bitStringValue;
@synthesize bitStringLength = _bitStringLength;
+ (instancetype)bitStringWithBitString: (OFData *)bitString
length: (size_t)length
{
return [[[self alloc] initWithBitString: bitString
length: length] autorelease];
}
- (instancetype)initWithBitString: (OFData *)bitString length: (size_t)length
{
self = [super init];
@try {
if (bitString.count * bitString.itemSize !=
OF_ROUND_UP_POW2(8, length) / 8)
@throw [OFInvalidFormatException exception];
_bitStringValue = [bitString copy];
_bitStringLength = length;
} @catch (id e) {
[self release];
@throw e;
}
return self;
}
- (instancetype)initWithTagClass: (of_asn1_tag_class_t)tagClass
tagNumber: (of_asn1_tag_number_t)tagNumber
constructed: (bool)constructed
DEREncodedContents: (OFData *)DEREncodedContents
{
void *pool = objc_autoreleasePoolPush();
OFData *bitString;
size_t length;
@try {
unsigned char unusedBits;
size_t count = DEREncodedContents.count;
if (tagClass != OF_ASN1_TAG_CLASS_UNIVERSAL ||
tagNumber != OF_ASN1_TAG_NUMBER_BIT_STRING || constructed)
@throw [OFInvalidArgumentException exception];
if (DEREncodedContents.itemSize != 1 || count == 0)
@throw [OFInvalidFormatException exception];
unusedBits =
*(unsigned char *)[DEREncodedContents itemAtIndex: 0];
if (unusedBits > 7)
@throw [OFInvalidFormatException exception];
/*
* Can't have any bits of the last byte unused if we have no
* byte.
*/
if (count == 1 && unusedBits != 0)
@throw [OFInvalidFormatException exception];
if (SIZE_MAX / 8 < count - 1)
@throw [OFOutOfRangeException exception];
length = (count - 1) * 8;
bitString = [DEREncodedContents subdataWithRange:
of_range(1, count - 1)];
if (unusedBits != 0)
length -= unusedBits;
} @catch (id e) {
[self release];
@throw e;
}
self = [self initWithBitString: bitString length: length];
objc_autoreleasePoolPop(pool);
return self;
}
- (instancetype)init
{
OF_INVALID_INIT_METHOD
}
- (void)dealloc
{
[_bitStringValue release];
[super dealloc];
}
- (OFData *)ASN1DERRepresentation
{
size_t bitStringValueCount = _bitStringValue.count;
size_t roundedUpLength = OF_ROUND_UP_POW2(8, _bitStringLength);
unsigned char unusedBits = roundedUpLength - _bitStringLength;
unsigned char header[] = {
OF_ASN1_TAG_NUMBER_BIT_STRING,
bitStringValueCount + 1,
unusedBits
};
OFMutableData *data;
if (bitStringValueCount + 1 > UINT8_MAX ||
bitStringValueCount != roundedUpLength / 8)
@throw [OFInvalidFormatException exception];
data = [OFMutableData
dataWithCapacity: sizeof(header) + bitStringValueCount];
[data addItems: header count: sizeof(header)];
[data addItems: _bitStringValue.items count: bitStringValueCount];
[data makeImmutable];
return data;
}
- (bool)isEqual: (id)object
{
OFASN1BitString *bitString;
if (object == self)
return true;
if (![object isKindOfClass: [OFASN1BitString class]])
return false;
bitString = object;
if (![bitString->_bitStringValue isEqual: _bitStringValue])
return false;
if (bitString->_bitStringLength != _bitStringLength)
return false;
return true;
}
- (unsigned long)hash
{
return _bitStringValue.hash + (unsigned long)_bitStringLength;
}
- (OFString *)description
{
return [OFString stringWithFormat: @"<OFASN1BitString: %@ (%zu bits)>",
_bitStringValue, _bitStringLength];
}
@end