Modified source engine (2017) developed by valve and leaked in 2020. Not for commercial purporses
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// ida.h - originally written and placed in the public domain by Wei Dai
/// \file ida.h
/// \brief Classes for Rabin's Information Dispersal and Shamir's Secret Sharing algorithms
#ifndef CRYPTOPP_IDA_H
#define CRYPTOPP_IDA_H
#include "cryptlib.h"
#include "mqueue.h"
#include "filters.h"
#include "channels.h"
#include "secblock.h"
#include "gf2_32.h"
#include "stdcpp.h"
#include "misc.h"
NAMESPACE_BEGIN(CryptoPP)
/// \brief Secret sharing and information dispersal base class
/// \since Crypto++ 1.0
class RawIDA : public AutoSignaling<Unflushable<Multichannel<Filter> > >
{
public:
RawIDA(BufferedTransformation *attachment=NULLPTR)
: m_channelsReady(0), m_channelsFinished(0), m_threshold (0)
{Detach(attachment);}
unsigned int GetThreshold() const {return m_threshold;}
void AddOutputChannel(word32 channelId);
void ChannelData(word32 channelId, const byte *inString, size_t length, bool messageEnd);
lword InputBuffered(word32 channelId) const;
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs);
size_t ChannelPut2(const std::string &channel, const byte *begin, size_t length, int messageEnd, bool blocking)
{
if (!blocking)
throw BlockingInputOnly("RawIDA");
ChannelData(StringToWord<word32>(channel), begin, length, messageEnd != 0);
return 0;
}
protected:
virtual void FlushOutputQueues();
virtual void OutputMessageEnds();
unsigned int InsertInputChannel(word32 channelId);
unsigned int LookupInputChannel(word32 channelId) const;
void ComputeV(unsigned int);
void PrepareInterpolation();
void ProcessInputQueues();
typedef std::map<word32, unsigned int> InputChannelMap;
InputChannelMap m_inputChannelMap;
InputChannelMap::iterator m_lastMapPosition;
std::vector<MessageQueue> m_inputQueues;
std::vector<word32> m_inputChannelIds, m_outputChannelIds, m_outputToInput;
std::vector<std::string> m_outputChannelIdStrings;
std::vector<ByteQueue> m_outputQueues;
std::vector<SecBlock<word32> > m_v;
SecBlock<word32> m_u, m_w, m_y;
const GF2_32 m_gf32;
unsigned int m_channelsReady, m_channelsFinished;
int m_threshold;
};
/// \brief Shamir's Secret Sharing Algorithm
/// \details SecretSharing is a variant of Shamir's secret sharing algorithm
/// \sa SecretRecovery, SecretRecovery, InformationDispersal, InformationRecovery
/// \since Crypto++ 1.0
class SecretSharing : public CustomFlushPropagation<Filter>
{
public:
/// \brief Construct a SecretSharing
SecretSharing(RandomNumberGenerator &rng, int threshold, int nShares, BufferedTransformation *attachment=NULLPTR, bool addPadding=true)
: m_rng(rng), m_ida(new OutputProxy(*this, true))
{
Detach(attachment);
IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("NumberOfShares", nShares)("AddPadding", addPadding));
}
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs);
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking);
bool Flush(bool hardFlush, int propagation=-1, bool blocking=true) {return m_ida.Flush(hardFlush, propagation, blocking);}
protected:
RandomNumberGenerator &m_rng;
RawIDA m_ida;
bool m_pad;
};
/// \brief Shamir's Secret Sharing Algorithm
/// \details SecretSharing is a variant of Shamir's secret sharing algorithm
/// \sa SecretRecovery, SecretRecovery, InformationDispersal, InformationRecovery
/// \since Crypto++ 1.0
class SecretRecovery : public RawIDA
{
public:
/// \brief Construct a SecretRecovery
SecretRecovery(int threshold, BufferedTransformation *attachment=NULLPTR, bool removePadding=true)
: RawIDA(attachment)
{IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("RemovePadding", removePadding));}
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs);
protected:
void FlushOutputQueues();
void OutputMessageEnds();
bool m_pad;
};
/// a variant of Rabin's Information Dispersal Algorithm
/// \brief Rabin's Information Dispersal Algorithm
/// \details InformationDispersal is a variant of Rabin's information dispersal algorithm
/// \sa SecretRecovery, SecretRecovery, InformationDispersal, InformationRecovery
/// \since Crypto++ 1.0
class InformationDispersal : public CustomFlushPropagation<Filter>
{
public:
/// \brief Construct a InformationDispersal
InformationDispersal(int threshold, int nShares, BufferedTransformation *attachment=NULLPTR, bool addPadding=true)
: m_ida(new OutputProxy(*this, true)), m_pad(false), m_nextChannel(0)
{
Detach(attachment);
IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("NumberOfShares", nShares)("AddPadding", addPadding));
}
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs);
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking);
bool Flush(bool hardFlush, int propagation=-1, bool blocking=true) {return m_ida.Flush(hardFlush, propagation, blocking);}
protected:
RawIDA m_ida;
bool m_pad;
unsigned int m_nextChannel;
};
/// \brief Rabin's Information Dispersal Algorithm
/// \details InformationDispersal is a variant of Rabin's information dispersal algorithm
/// \sa SecretRecovery, SecretRecovery, InformationDispersal, InformationRecovery
/// \since Crypto++ 1.0
class InformationRecovery : public RawIDA
{
public:
/// \brief Construct a InformationRecovery
InformationRecovery(int threshold, BufferedTransformation *attachment=NULLPTR, bool removePadding=true)
: RawIDA(attachment), m_pad(false)
{IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("RemovePadding", removePadding));}
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs);
protected:
void FlushOutputQueues();
void OutputMessageEnds();
bool m_pad;
ByteQueue m_queue;
};
class PaddingRemover : public Unflushable<Filter>
{
public:
PaddingRemover(BufferedTransformation *attachment=NULLPTR)
: m_possiblePadding(false), m_zeroCount(0) {Detach(attachment);}
void IsolatedInitialize(const NameValuePairs &parameters)
{CRYPTOPP_UNUSED(parameters); m_possiblePadding = false;}
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking);
// GetPossiblePadding() == false at the end of a message indicates incorrect padding
bool GetPossiblePadding() const {return m_possiblePadding;}
private:
bool m_possiblePadding;
lword m_zeroCount;
};
NAMESPACE_END
#endif