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Diffstat (limited to '')
| -rw-r--r-- | CryptoPP/ida.h | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/CryptoPP/ida.h b/CryptoPP/ida.h new file mode 100644 index 000000000..8ebb4ec91 --- /dev/null +++ b/CryptoPP/ida.h @@ -0,0 +1,152 @@ +#ifndef CRYPTOPP_IDA_H +#define CRYPTOPP_IDA_H + +#include "mqueue.h" +#include "filters.h" +#include "channels.h" +#include <map> +#include <vector> + +NAMESPACE_BEGIN(CryptoPP) + +/// base class for secret sharing and information dispersal +class RawIDA : public AutoSignaling<Unflushable<Multichannel<Filter> > > +{ +public: + RawIDA(BufferedTransformation *attachment=NULL) + {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 ¶meters=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; + int m_threshold; + unsigned int m_channelsReady, m_channelsFinished; + std::vector<SecBlock<word32> > m_v; + SecBlock<word32> m_u, m_w, m_y; +}; + +/// a variant of Shamir's Secret Sharing Algorithm +class SecretSharing : public CustomFlushPropagation<Filter> +{ +public: + SecretSharing(RandomNumberGenerator &rng, int threshold, int nShares, BufferedTransformation *attachment=NULL, 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 ¶meters=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; +}; + +/// a variant of Shamir's Secret Sharing Algorithm +class SecretRecovery : public RawIDA +{ +public: + SecretRecovery(int threshold, BufferedTransformation *attachment=NULL, bool removePadding=true) + : RawIDA(attachment) + {IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("RemovePadding", removePadding));} + + void IsolatedInitialize(const NameValuePairs ¶meters=g_nullNameValuePairs); + +protected: + void FlushOutputQueues(); + void OutputMessageEnds(); + + bool m_pad; +}; + +/// a variant of Rabin's Information Dispersal Algorithm +class InformationDispersal : public CustomFlushPropagation<Filter> +{ +public: + InformationDispersal(int threshold, int nShares, BufferedTransformation *attachment=NULL, bool addPadding=true) + : m_ida(new OutputProxy(*this, true)) + { + Detach(attachment); + IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("NumberOfShares", nShares)("AddPadding", addPadding)); + } + + void IsolatedInitialize(const NameValuePairs ¶meters=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; +}; + +/// a variant of Rabin's Information Dispersal Algorithm +class InformationRecovery : public RawIDA +{ +public: + InformationRecovery(int threshold, BufferedTransformation *attachment=NULL, bool removePadding=true) + : RawIDA(attachment) + {IsolatedInitialize(MakeParameters("RecoveryThreshold", threshold)("RemovePadding", removePadding));} + + void IsolatedInitialize(const NameValuePairs ¶meters=g_nullNameValuePairs); + +protected: + void FlushOutputQueues(); + void OutputMessageEnds(); + + bool m_pad; + ByteQueue m_queue; +}; + +class PaddingRemover : public Unflushable<Filter> +{ +public: + PaddingRemover(BufferedTransformation *attachment=NULL) + : m_possiblePadding(false) {Detach(attachment);} + + void IsolatedInitialize(const NameValuePairs ¶meters) {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 |