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iterhash.h

00001 #ifndef CRYPTOPP_ITERHASH_H 00002 #define CRYPTOPP_ITERHASH_H 00003 00004 #include "cryptlib.h" 00005 #include "secblock.h" 00006 #include "misc.h" 00007 #include "simple.h" 00008 00009 NAMESPACE_BEGIN(CryptoPP) 00010 00011 //! _ 00012 template <class T, class BASE> 00013 class CRYPTOPP_NO_VTABLE IteratedHashBase : public BASE 00014 { 00015 public: 00016 typedef T HashWordType; 00017 00018 IteratedHashBase() : m_countHi(0), m_countLo(0) {} 00019 unsigned int BlockSize() const {return m_data.size() * sizeof(T);} 00020 unsigned int OptimalBlockSize() const {return BlockSize();} 00021 unsigned int OptimalDataAlignment() const {return sizeof(T);} 00022 void Update(const byte *input, unsigned int length); 00023 byte * CreateUpdateSpace(unsigned int &size); 00024 void Restart(); 00025 00026 protected: 00027 void SetBlockSize(unsigned int blockSize) {m_data.resize(blockSize / sizeof(HashWordType));} 00028 void SetStateSize(unsigned int stateSize) {m_digest.resize(stateSize / sizeof(HashWordType));} 00029 00030 T GetBitCountHi() const {return (m_countLo >> (8*sizeof(T)-3)) + (m_countHi << 3);} 00031 T GetBitCountLo() const {return m_countLo << 3;} 00032 00033 virtual unsigned int HashMultipleBlocks(const T *input, unsigned int length); 00034 void PadLastBlock(unsigned int lastBlockSize, byte padFirst=0x80); 00035 virtual void Init() =0; 00036 virtual void HashBlock(const T *input) =0; 00037 00038 SecBlock<T> m_data; // Data buffer 00039 SecBlock<T> m_digest; // Message digest 00040 00041 private: 00042 T m_countLo, m_countHi; 00043 }; 00044 00045 #ifdef WORD64_AVAILABLE 00046 CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word64, HashTransformation>; 00047 CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word64, MessageAuthenticationCode>; 00048 #endif 00049 00050 CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word32, HashTransformation>; 00051 CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word32, MessageAuthenticationCode>; 00052 00053 //! _ 00054 template <class T, class B, class BASE> 00055 class CRYPTOPP_NO_VTABLE IteratedHashBase2 : public IteratedHashBase<T, BASE> 00056 { 00057 public: 00058 typedef B ByteOrderClass; 00059 typedef typename IteratedHashBase<T, BASE>::HashWordType HashWordType; 00060 00061 inline static void CorrectEndianess(HashWordType *out, const HashWordType *in, unsigned int byteCount) 00062 { 00063 ConditionalByteReverse(B::ToEnum(), out, in, byteCount); 00064 } 00065 00066 void TruncatedFinal(byte *digest, unsigned int size); 00067 00068 protected: 00069 void HashBlock(const HashWordType *input); 00070 virtual void HashEndianCorrectedBlock(const HashWordType *data) =0; 00071 }; 00072 00073 //! _ 00074 template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, class T_Base = HashTransformation> 00075 class CRYPTOPP_NO_VTABLE IteratedHash : public IteratedHashBase2<T_HashWordType, T_Endianness, T_Base> 00076 { 00077 public: 00078 enum {BLOCKSIZE = T_BlockSize}; 00079 CRYPTOPP_COMPILE_ASSERT((BLOCKSIZE & (BLOCKSIZE - 1)) == 0); // blockSize is a power of 2 00080 00081 protected: 00082 IteratedHash() {this->SetBlockSize(T_BlockSize);} 00083 }; 00084 00085 //! _ 00086 template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, unsigned int T_StateSize, class T_Transform, unsigned int T_DigestSize = T_StateSize> 00087 class CRYPTOPP_NO_VTABLE IteratedHashWithStaticTransform 00088 : public ClonableImpl<T_Transform, AlgorithmImpl<IteratedHash<T_HashWordType, T_Endianness, T_BlockSize>, T_Transform> > 00089 { 00090 public: 00091 enum {DIGESTSIZE = T_DigestSize}; 00092 unsigned int DigestSize() const {return DIGESTSIZE;}; 00093 00094 protected: 00095 IteratedHashWithStaticTransform() 00096 { 00097 this->SetStateSize(T_StateSize); 00098 Init(); 00099 } 00100 void HashEndianCorrectedBlock(const T_HashWordType *data) {T_Transform::Transform(this->m_digest, data);} 00101 void Init() {T_Transform::InitState(this->m_digest);} 00102 }; 00103 00104 // ************************************************************* 00105 00106 template <class T, class B, class BASE> void IteratedHashBase2<T, B, BASE>::TruncatedFinal(byte *digest, unsigned int size) 00107 { 00108 this->ThrowIfInvalidTruncatedSize(size); 00109 00110 PadLastBlock(this->BlockSize() - 2*sizeof(HashWordType)); 00111 CorrectEndianess(this->m_data, this->m_data, this->BlockSize() - 2*sizeof(HashWordType)); 00112 00113 this->m_data[this->m_data.size()-2] = B::ToEnum() ? this->GetBitCountHi() : this->GetBitCountLo(); 00114 this->m_data[this->m_data.size()-1] = B::ToEnum() ? this->GetBitCountLo() : this->GetBitCountHi(); 00115 00116 HashEndianCorrectedBlock(this->m_data); 00117 CorrectEndianess(this->m_digest, this->m_digest, this->DigestSize()); 00118 memcpy(digest, this->m_digest, size); 00119 00120 this->Restart(); // reinit for next use 00121 } 00122 00123 template <class T, class B, class BASE> void IteratedHashBase2<T, B, BASE>::HashBlock(const HashWordType *input) 00124 { 00125 if (NativeByteOrderIs(B::ToEnum())) 00126 HashEndianCorrectedBlock(input); 00127 else 00128 { 00129 ByteReverse(this->m_data.begin(), input, this->BlockSize()); 00130 HashEndianCorrectedBlock(this->m_data); 00131 } 00132 } 00133 00134 NAMESPACE_END 00135 00136 #endif

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