Kdb3Reader.m

//
//   Kdb3.m
//   KeePass
//
//   Created by Qiang Yu on 11/22/09.
//   Copyright 2009 Qiang Yu. All rights reserved.
//

#import "Kdb3Reader.h"
#import "UUID.h"
#import "Utils.h"
#import "Kdb3Parser.h"
#import "AESDecryptSource.h"

#define READ_BYTES(X, Y, Z) (X = [[ByteBuffer alloc] initWithSize:Y dataSource:Z])

@interface Kdb3Reader (privateMethods)
-(id<InputDataSource>)createDecryptedInputDataSource:(id<InputDataSource>)source key:(ByteBuffer *)key;
-(void)readHeader:(id<InputDataSource>) source;
@end

@implementation Kdb3Reader
@synthesize _tree;

#pragma mark -
#pragma mark alloc/dealloc

-(void)dealloc{
	[_tree release];
	[super dealloc];
}

#pragma mark -
#pragma mark private methods
-(void)readHeader:(id<InputDataSource>) input{
	uint32_t flags, version;	
	
	flags = [Utils readInt32LE:input]; 
	version = [Utils readInt32LE:input];
	
	if((version & 0xFFFFFF00)!=(KDB3_VER & 0xFFFFFF00)){
		@throw [NSException exceptionWithName:@"Unsupported" reason:@"UnsupportedVersion" userInfo:nil];
	}	
		
	if(!(flags & FLAG_RIJNDAEL)) 
		@throw [NSException exceptionWithName:@"Unsupported" reason:@"UnsupportedAlgorithm" userInfo:nil];	

	
	ByteBuffer * masterSeed;
	READ_BYTES(masterSeed, 16, input);
	_password._masterSeed = masterSeed;
	[masterSeed release];
	[input readBytes:_encryptionIV length:16];
	_numGroups = [Utils readInt32LE:input];
	_numEntries = [Utils readInt32LE:input];
	
	//DLog(@"group# %d entry #%d", _numGroups, _numEntries);
	
	[input readBytes:_contentHash length:32];	

	ByteBuffer * transformSeed = nil;
	READ_BYTES(transformSeed, 32, input);	
	_password._transformSeed = transformSeed;
	[transformSeed release];
	
	_password._rounds = [Utils readInt32LE:input];
}


-(id<InputDataSource>)createDecryptedInputDataSource:(id<InputDataSource>)source key:(ByteBuffer *)key{	
	AESDecryptSource * rv = [[AESDecryptSource alloc]initWithInputSource:source Keys:key._bytes andIV:_encryptionIV];
	return rv;
}


#pragma mark -
#pragma mark public methods
-(id<KdbTree>)load:(WrapperNSData *)input withPassword:(NSString *)password{
	_password = [[KdbPassword alloc]init];
	[self readHeader:input];
	ByteBuffer * finalKey = nil;
	id<InputDataSource> decrypted = nil;
	Kdb3Parser * parser;
	@try{
		finalKey= [_password createFinalKey32ForPasssword:password coding:NSWindowsCP1252StringEncoding kdbVersion:3];
		decrypted = [self createDecryptedInputDataSource:input key:finalKey];
		
		parser = [[Kdb3Parser alloc]init];
		self._tree = [parser parse:decrypted numGroups:_numGroups numEntris:_numEntries];
	}@finally {
		[parser release];
		[finalKey release];
		[decrypted release];
		[_password release];
	}
	return self._tree;
}

-(id<KdbTree>)getKdbTree{
	return self._tree;
}

@end