encfs/encfs/FSConfig.h

/*****************************************************************************
 * Author:   Valient Gough <vgough@pobox.com>
 *
 *****************************************************************************
 * Copyright (c) 2010 Valient Gough
 *
 * This program is free software: you can redistribute it and/or modify it 
 * under the terms of the GNU 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 General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef _FSConfig_incl_
#define _FSConfig_incl_

#include "encfs.h"
#include "Interface.h"
#include "CipherKey.h"

#include <vector>
#include <boost/shared_ptr.hpp>

enum ConfigType
{
    Config_None = 0,
    Config_Prehistoric,
    Config_V3,
    Config_V4,
    Config_V5,
    Config_V6
};

class EncFS_Opts;
class Cipher;
class NameIO;

struct EncFSConfig
{
    ConfigType cfgType;

    std::string creator;
    int subVersion;

    // interface of cipher
    rel::Interface cipherIface;
    // interface used for file name coding
    rel::Interface nameIface;
    int keySize; // reported in bits
    int blockSize; // reported in bytes

    std::vector<unsigned char> keyData;

    std::vector<unsigned char> salt;
    int kdfIterations;
    long desiredKDFDuration;

    int blockMACBytes; // MAC headers on blocks..
    int blockMACRandBytes; // number of random bytes in the block header

    bool uniqueIV; // per-file Initialization Vector
    bool externalIVChaining; // IV seeding by filename IV chaining

    bool chainedNameIV; // filename IV chaining
    bool allowHoles; // allow holes in files (implicit zero blocks)

    EncFSConfig()
        : keyData()
        , salt()
    {
        cfgType = Config_None;
        subVersion = 0;
        blockMACBytes = 0;
        blockMACRandBytes = 0;
        uniqueIV = false;
        externalIVChaining = false;
        chainedNameIV = false;
        allowHoles = false;

        kdfIterations = 0;
        desiredKDFDuration = 500;
    }

    CipherKey getUserKey(bool useStdin);
    CipherKey getUserKey(const std::string &passwordProgram,
                         const std::string &rootDir);
    CipherKey getNewUserKey();
    
    boost::shared_ptr<Cipher> getCipher() const;

    // deprecated
    void assignKeyData(const std::string &in);
    void assignKeyData(unsigned char *data, int length);
    void assignSaltData(unsigned char *data, int length);

    unsigned char *getKeyData() const;
    unsigned char *getSaltData() const;

private:
    CipherKey makeKey(const char *password, int passwdLen);
};
   
// helpers for serializing to/from a stream
std::ostream &operator << (std::ostream &os, const EncFSConfig &cfg);
std::istream &operator >> (std::istream &os, EncFSConfig &cfg);

struct FSConfig
{
    boost::shared_ptr<EncFSConfig> config;
    boost::shared_ptr<EncFS_Opts> opts;

    boost::shared_ptr<Cipher> cipher;
    CipherKey key;
    boost::shared_ptr<NameIO> nameCoding;

    bool forceDecode; // force decode on MAC block failures
    bool reverseEncryption; // reverse encryption operation

    bool idleTracking; // turn on idle monitoring of filesystem
};

typedef boost::shared_ptr<FSConfig> FSConfigPtr;

#endif