ObjFW  Diff

 */

#include "config.h"

#include <string.h>

#import "OFMD5Hash.h"
#import "OFSecureData.h"

#import "OFHashAlreadyCalculatedException.h"
#import "OFOutOfRangeException.h"

@interface OFMD5Hash ()
- (void)of_resetState;
@end

#define F(a, b, c) (((a) & (b)) | (~(a) & (c)))
#define G(a, b, c) (((a) & (c)) | ((b) & ~(c)))

	7, 12, 17, 22,
	5, 9, 14, 20,
	4, 11, 16, 23,
	6, 10, 15, 21
};

static OF_INLINE void
byteSwapVectorIfBE(uint32_t *vector, uint8_t length)
byteSwapVectorIfBE(uint32_t *vector, uint_fast8_t length)
{
#ifdef OF_BIG_ENDIAN
	for (uint8_t i = 0; i < length; i++)
	for (uint_fast8_t i = 0; i < length; i++)
		vector[i] = OF_BSWAP32(vector[i]);
#endif
}

static void
processBlock(uint32_t *state, uint32_t *buffer)
{
	uint32_t new[4];
	uint8_t i = 0;
	uint_fast8_t i = 0;

	new[0] = state[0];
	new[1] = state[1];
	new[2] = state[2];
	new[3] = state[3];

	byteSwapVectorIfBE(buffer, 16);

	return [[[self alloc] init] autorelease];
}

- (instancetype)init
{
	self = [super init];

	@try {
		_iVarsData = [[OFSecureData alloc]
		    initWithCount: sizeof(*_iVars)];
		_iVars = [_iVarsData items];

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

	return self;
}

- (instancetype)of_init
{
	return [super init];
}

- (void)dealloc
{
	[self reset];
	[_iVarsData release];

	[super dealloc];
}

- (id)copy
{
	OFMD5Hash *copy = [[OFMD5Hash alloc] init];
	OFMD5Hash *copy = [[OFMD5Hash alloc] of_init];

	memcpy(copy->_state, _state, sizeof(_state));
	copy->_bits = _bits;
	copy->_iVarsData = [_iVarsData copy];
	memcpy(&copy->_buffer, &_buffer, sizeof(_buffer));
	copy->_bufferLength = _bufferLength;
	copy->_iVars = [copy->_iVarsData items];
	copy->_calculated = _calculated;

	return copy;
}

- (void)of_resetState
{
	_state[0] = 0x67452301;
	_state[1] = 0xEFCDAB89;
	_state[2] = 0x98BADCFE;
	_state[3] = 0x10325476;
	_iVars->state[0] = 0x67452301;
	_iVars->state[1] = 0xEFCDAB89;
	_iVars->state[2] = 0x98BADCFE;
	_iVars->state[3] = 0x10325476;
}

- (void)updateWithBuffer: (const void *)buffer_
		  length: (size_t)length
{
	const uint8_t *buffer = buffer_;
	const unsigned char *buffer = buffer_;

	if (_calculated)
		@throw [OFHashAlreadyCalculatedException
		    exceptionWithObject: self];

	if (length > SIZE_MAX / 8)
		@throw [OFOutOfRangeException exception];

	_bits += (length * 8);
	_iVars->bits += (length * 8);

	while (length > 0) {
		size_t min = 64 - _bufferLength;
		size_t min = 64 - _iVars->bufferLength;

		if (min > length)
			min = length;

		memcpy(_iVars->buffer.bytes + _iVars->bufferLength,
		memcpy(_buffer.bytes + _bufferLength, buffer, min);
		_bufferLength += min;
		    buffer, min);
		_iVars->bufferLength += min;

		buffer += min;
		length -= min;

		if (_bufferLength == 64) {
			processBlock(_state, _buffer.words);
			_bufferLength = 0;
		if (_iVars->bufferLength == 64) {
			processBlock(_iVars->state, _iVars->buffer.words);
			_iVars->bufferLength = 0;
		}
	}
}

- (const unsigned char *)digest
{
	if (_calculated)
		return (const uint8_t *)_state;
		return (const unsigned char *)_iVars->state;

	_buffer.bytes[_bufferLength] = 0x80;
	memset(_buffer.bytes + _bufferLength + 1, 0, 64 - _bufferLength - 1);
	_iVars->buffer.bytes[_iVars->bufferLength] = 0x80;
	of_explicit_memset(_iVars->buffer.bytes + _iVars->bufferLength + 1, 0,
	    64 - _iVars->bufferLength - 1);

	if (_bufferLength >= 56) {
		processBlock(_state, _buffer.words);
		memset(_buffer.bytes, 0, 64);
	if (_iVars->bufferLength >= 56) {
		processBlock(_iVars->state, _iVars->buffer.words);
		of_explicit_memset(_iVars->buffer.bytes, 0, 64);
	}

	_iVars->buffer.words[14] =
	_buffer.words[14] = OF_BSWAP32_IF_BE((uint32_t)(_bits & 0xFFFFFFFF));
	_buffer.words[15] = OF_BSWAP32_IF_BE((uint32_t)(_bits >> 32));
	    OF_BSWAP32_IF_BE((uint32_t)(_iVars->bits & 0xFFFFFFFF));
	_iVars->buffer.words[15] =
	    OF_BSWAP32_IF_BE((uint32_t)(_iVars->bits >> 32));

	processBlock(_state, _buffer.words);
	memset(&_buffer, 0, sizeof(_buffer));
	byteSwapVectorIfBE(_state, 4);
	processBlock(_iVars->state, _iVars->buffer.words);
	of_explicit_memset(&_iVars->buffer, 0, sizeof(_iVars->buffer));
	byteSwapVectorIfBE(_iVars->state, 4);
	_calculated = true;

	return (const uint8_t *)_state;
	return (const unsigned char *)_iVars->state;
}

- (void)reset
{
	[self of_resetState];
	_bits = 0;
	memset(&_buffer, 0, sizeof(_buffer));
	_bufferLength = 0;
	_iVars->bits = 0;
	of_explicit_memset(&_iVars->buffer, 0, sizeof(_iVars->buffer));
	_iVars->bufferLength = 0;
	_calculated = false;
}
@end