panama.h

#ifndef CRYPTOPP_PANAMA_H
#define CRYPTOPP_PANAMA_H

#include "seckey.h"
#include "secblock.h"
#include "strciphr.h"
#include "iterhash.h"

NAMESPACE_BEGIN(CryptoPP)

/// base class, do not use directly
template <class B>
class CRYPTOPP_NO_VTABLE Panama
{
public:
        void Reset();
        void Iterate(size_t count, const word32 *p=NULL, word32 *z=NULL, const word32 *y=NULL);

protected:
        typedef word32 Stage[8];
        CRYPTOPP_CONSTANT(STAGES = 32)

        FixedSizeSecBlock<word32, 17*2 + 32*sizeof(Stage)> m_state;
        unsigned int m_bstart;
};

/// <a href="http://www.weidai.com/scan-mirror/md.html#Panama">Panama Hash</a>
template <class B = LittleEndian>
class PanamaHash : protected Panama<B>, public AlgorithmImpl<IteratedHash<word32, NativeByteOrder, 32>, PanamaHash<B> >
{
public:
        CRYPTOPP_CONSTANT(DIGESTSIZE = 32)
        PanamaHash() {Panama<B>::Reset();}
        unsigned int DigestSize() const {return DIGESTSIZE;}
        void TruncatedFinal(byte *hash, size_t size);
        static const char * StaticAlgorithmName() {return B::ToEnum() == BIG_ENDIAN_ORDER ? "Panama-BE" : "Panama-LE";}

protected:
        void Init() {Panama<B>::Reset();}
        void HashEndianCorrectedBlock(const word32 *data) {this->Iterate(1, data);}     // push
        size_t HashMultipleBlocks(const word32 *input, size_t length);
};

//! MAC construction using a hermetic hash function
template <class T_Hash, class T_Info = T_Hash>
class HermeticHashFunctionMAC : public AlgorithmImpl<SimpleKeyingInterfaceImpl<TwoBases<MessageAuthenticationCode, VariableKeyLength<32, 0, INT_MAX> > >, T_Info>
{
public:
        void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params)
        {
                m_key.Assign(key, length);
                Restart();
        }

        void Restart()
        {
                m_hash.Restart();
                m_keyed = false;
        }

        void Update(const byte *input, size_t length)
        {
                if (!m_keyed)
                        KeyHash();
                m_hash.Update(input, length);
        }

        void TruncatedFinal(byte *digest, size_t digestSize)
        {
                if (!m_keyed)
                        KeyHash();
                m_hash.TruncatedFinal(digest, digestSize);
                m_keyed = false;
        }

        unsigned int DigestSize() const
                {return m_hash.DigestSize();}
        unsigned int BlockSize() const
                {return m_hash.BlockSize();}
        unsigned int OptimalBlockSize() const
                {return m_hash.OptimalBlockSize();}
        unsigned int OptimalDataAlignment() const
                {return m_hash.OptimalDataAlignment();}

protected:
        void KeyHash()
        {
                m_hash.Update(m_key, m_key.size());
                m_keyed = true;
        }

        T_Hash m_hash;
        bool m_keyed;
        SecByteBlock m_key;
};

/// Panama MAC
template <class B = LittleEndian>
class PanamaMAC : public HermeticHashFunctionMAC<PanamaHash<B> >
{
public:
        PanamaMAC() {}
        PanamaMAC(const byte *key, unsigned int length)
                {this->SetKey(key, length);}
};

//! algorithm info
template <class B>
struct PanamaCipherInfo : public VariableKeyLength<32, 32, 64, 32, SimpleKeyingInterface::NOT_RESYNCHRONIZABLE>
{
        static const char * StaticAlgorithmName() {return B::ToEnum() == BIG_ENDIAN_ORDER ? "Panama-BE" : "Panama-LE";}
};

//! _
template <class B>
class PanamaCipherPolicy : public AdditiveCipherConcretePolicy<word32, 8>, 
                                                        public PanamaCipherInfo<B>,
                                                        protected Panama<B>
{
protected:
        void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length);
        void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount);
        bool IsRandomAccess() const {return false;}
};

//! <a href="http://www.weidai.com/scan-mirror/cs.html#Panama">Panama Stream Cipher</a>
template <class B = LittleEndian>
struct PanamaCipher : public PanamaCipherInfo<B>, public SymmetricCipherDocumentation
{
        typedef SymmetricCipherFinal<ConcretePolicyHolder<PanamaCipherPolicy<B>, AdditiveCipherTemplate<> >, PanamaCipherInfo<B> > Encryption;
        typedef Encryption Decryption;
};

NAMESPACE_END

#endif

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