encfs/fs/CipherFileIO.h
Valient Gough 63c2d1c539 add CommonCrypto support, other misc fixes
git-svn-id: http://encfs.googlecode.com/svn/trunk@97 db9cf616-1c43-0410-9cb8-a902689de0d6
2013-03-05 06:39:51 +00:00

100 lines
2.8 KiB
C++

/*****************************************************************************
* Author: Valient Gough <vgough@pobox.com>
*
*****************************************************************************
* Copyright (c) 2004, Valient Gough
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _CipherFileIO_incl_
#define _CipherFileIO_incl_
#include "cipher/CipherKey.h"
#include "fs/BlockFileIO.h"
#include "fs/FileUtils.h"
#include <inttypes.h>
namespace encfs {
class CipherV1;
/*
Implement the FileIO interface encrypting data in blocks.
Uses BlockFileIO to handle the block scatter / gather issues.
*/
class CipherFileIO : public BlockFileIO
{
public:
CipherFileIO( const shared_ptr<FileIO> &base,
const FSConfigPtr &cfg);
virtual ~CipherFileIO();
virtual Interface interface() const;
virtual void setFileName( const char *fileName );
virtual const char *getFileName() const;
virtual bool setIV( uint64_t iv );
virtual int open( int flags );
virtual int getAttr( struct stat *stbuf ) const;
virtual off_t getSize() const;
// NOTE: if truncate is used to extend the file, the extended plaintext is
// not 0. The extended ciphertext may be 0, resulting in non-zero
// plaintext.
virtual int truncate( off_t size );
virtual bool isWritable() const;
private:
virtual ssize_t readOneBlock( const IORequest &req ) const;
virtual bool writeOneBlock( const IORequest &req );
void initHeader();
bool writeHeader();
bool blockRead( unsigned char *buf, int size,
uint64_t iv64 ) const;
bool streamRead( unsigned char *buf, int size,
uint64_t iv64 ) const;
bool blockWrite( unsigned char *buf, int size,
uint64_t iv64 ) const;
bool streamWrite( unsigned char *buf, int size,
uint64_t iv64 ) const;
off_t adjustedSize(off_t size) const;
shared_ptr<FileIO> base;
FSConfigPtr fsConfig;
// if haveHeader is true, then we have a transparent file header which
int headerLen;
bool perFileIV;
bool externalIVChaining;
uint64_t externalIV;
uint64_t fileIV;
int lastFlags;
shared_ptr<CipherV1> cipher;
};
} // namespace encfs
#endif