encfs/encfs/NameIO.h
2014-10-18 19:19:33 -07:00

130 lines
4.6 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 _NameIO_incl_
#define _NameIO_incl_
#include <string>
#include <list>
#include <inttypes.h>
#include "Interface.h"
#include "CipherKey.h"
class Cipher;
class NameIO {
public:
typedef shared_ptr<NameIO>(*Constructor)(const rel::Interface &iface,
const shared_ptr<Cipher> &cipher,
const CipherKey &key);
struct Algorithm {
std::string name;
std::string description;
rel::Interface iface;
};
typedef std::list<Algorithm> AlgorithmList;
static AlgorithmList GetAlgorithmList(bool includeHidden = false);
static shared_ptr<NameIO> New(const rel::Interface &iface,
const shared_ptr<Cipher> &cipher,
const CipherKey &key);
static shared_ptr<NameIO> New(const std::string &name,
const shared_ptr<Cipher> &cipher,
const CipherKey &key);
static bool Register(const char *name, const char *description,
const rel::Interface &iface, Constructor constructor,
bool hidden = false);
NameIO();
virtual ~NameIO();
virtual rel::Interface interface() const = 0;
void setChainedNameIV(bool enable);
bool getChainedNameIV() const;
void setReverseEncryption(bool enable);
bool getReverseEncryption() const;
std::string encodePath(const char *plaintextPath) const;
std::string decodePath(const char *encodedPath) const;
std::string encodePath(const char *plaintextPath, uint64_t *iv) const;
std::string decodePath(const char *encodedPath, uint64_t *iv) const;
virtual int maxEncodedNameLen(int plaintextNameLen) const = 0;
virtual int maxDecodedNameLen(int encodedNameLen) const = 0;
std::string encodeName(const char *plaintextName, int length) const;
std::string decodeName(const char *encodedName, int length) const;
protected:
virtual int encodeName(const char *plaintextName, int length,
char *encodedName) const;
virtual int decodeName(const char *encodedName, int length,
char *plaintextName) const;
virtual int encodeName(const char *plaintextName, int length, uint64_t *iv,
char *encodedName) const = 0;
virtual int decodeName(const char *encodedName, int length, uint64_t *iv,
char *plaintextName) const = 0;
private:
std::string recodePath(const char *path, int (NameIO::*codingLen)(int) const,
int (NameIO::*codingFunc)(const char *, int,
uint64_t *, char *) const,
uint64_t *iv) const;
std::string _encodePath(const char *plaintextPath, uint64_t *iv) const;
std::string _decodePath(const char *encodedPath, uint64_t *iv) const;
std::string _encodeName(const char *plaintextName, int length) const;
std::string _decodeName(const char *encodedName, int length) const;
bool chainedNameIV;
bool reverseEncryption;
};
/*
Helper macros for creating temporary buffers with an optimization that
below a given size (OptimizedSize) is allocated on the stack, and when a
larger size is requested it is allocated on the heap.
BUFFER_RESET should be called for the same name as BUFFER_INIT
*/
#define BUFFER_INIT(Name, OptimizedSize, Size) \
char Name##_Raw[OptimizedSize]; \
char *Name = Name##_Raw; \
if (sizeof(Name##_Raw) < Size) Name = new char[Size]; \
memset(Name, 0, Size);
#define BUFFER_RESET(Name) \
do { \
if (Name != Name##_Raw) { \
delete[] Name; \
Name = Name##_Raw; \
} \
} while (0);
#endif