Crypto++  8.2
Free C++ class library of cryptographic schemes
iterhash.h
1 // iterhash.h - originally written and placed in the public domain by Wei Dai
2 
3 #ifndef CRYPTOPP_ITERHASH_H
4 #define CRYPTOPP_ITERHASH_H
5 
6 #include "cryptlib.h"
7 #include "secblock.h"
8 #include "misc.h"
9 #include "simple.h"
10 
11 #if CRYPTOPP_MSC_VERSION
12 # pragma warning(push)
13 # pragma warning(disable: 4231 4275)
14 # if (CRYPTOPP_MSC_VERSION >= 1400)
15 # pragma warning(disable: 6011 6386 28193)
16 # endif
17 #endif
18 
19 NAMESPACE_BEGIN(CryptoPP)
20 
21 /// \brief Exception thrown when trying to hash more data than is allowed by a hash function
22 class CRYPTOPP_DLL HashInputTooLong : public InvalidDataFormat
23 {
24 public:
25  explicit HashInputTooLong(const std::string &alg)
26  : InvalidDataFormat("IteratedHashBase: input data exceeds maximum allowed by hash function " + alg) {}
27 };
28 
29 /// \brief Iterated hash base class
30 /// \tparam T Hash word type
31 /// \tparam BASE HashTransformation derived class
32 /// \details IteratedHashBase provides an interface for block-based iterated hashes
33 /// \sa HashTransformation, MessageAuthenticationCode
34 template <class T, class BASE>
35 class CRYPTOPP_NO_VTABLE IteratedHashBase : public BASE
36 {
37 public:
38  typedef T HashWordType;
39 
40  virtual ~IteratedHashBase() {}
41 
42  /// \brief Construct an IteratedHashBase
43  IteratedHashBase() : m_countLo(0), m_countHi(0) {}
44 
45  /// \brief Provides the input block size most efficient for this cipher.
46  /// \return The input block size that is most efficient for the cipher
47  /// \details The base class implementation returns MandatoryBlockSize().
48  /// \note Optimal input length is
49  /// <tt>n * OptimalBlockSize() - GetOptimalBlockSizeUsed()</tt> for any <tt>n > 0</tt>.
50  unsigned int OptimalBlockSize() const {return this->BlockSize();}
51 
52  /// \brief Provides input and output data alignment for optimal performance.
53  /// \return the input data alignment that provides optimal performance
54  /// \details OptimalDataAlignment returns the natural alignment of the hash word.
55  unsigned int OptimalDataAlignment() const {return GetAlignmentOf<T>();}
56 
57  /// \brief Updates a hash with additional input
58  /// \param input the additional input as a buffer
59  /// \param length the size of the buffer, in bytes
60  void Update(const byte *input, size_t length);
61 
62  /// \brief Requests space which can be written into by the caller
63  /// \param size the requested size of the buffer
64  /// \details The purpose of this method is to help avoid extra memory allocations.
65  /// \details size is an \a IN and \a OUT parameter and used as a hint. When the call is made,
66  /// size is the requested size of the buffer. When the call returns, size is the size of
67  /// the array returned to the caller.
68  /// \details The base class implementation sets size to 0 and returns NULL.
69  /// \note Some objects, like ArraySink, cannot create a space because its fixed.
70  byte * CreateUpdateSpace(size_t &size);
71 
72  /// \brief Restart the hash
73  /// \details Discards the current state, and restart for a new message
74  void Restart();
75 
76  /// \brief Computes the hash of the current message
77  /// \param digest a pointer to the buffer to receive the hash
78  /// \param digestSize the size of the truncated digest, in bytes
79  /// \details TruncatedFinal() call Final() and then copies digestSize bytes to digest.
80  /// The hash is restarted the hash for the next message.
81  void TruncatedFinal(byte *digest, size_t digestSize);
82 
83  /// \brief Retrieve the provider of this algorithm
84  /// \return the algorithm provider
85  /// \details The algorithm provider can be a name like "C++", "SSE", "NEON", "AESNI",
86  /// "ARMv8" and "Power8". C++ is standard C++ code. Other labels, like SSE,
87  /// usually indicate a specialized implementation using instructions from a higher
88  /// instruction set architecture (ISA). Future labels may include external hardware
89  /// like a hardware security module (HSM).
90  /// \note Provider is not universally implemented yet.
91  virtual std::string AlgorithmProvider() const { return "C++"; }
92 
93 protected:
94  inline T GetBitCountHi() const
95  {return (m_countLo >> (8*sizeof(T)-3)) + (m_countHi << 3);}
96  inline T GetBitCountLo() const
97  {return m_countLo << 3;}
98 
99  void PadLastBlock(unsigned int lastBlockSize, byte padFirst=0x80);
100  virtual void Init() =0;
101 
102  virtual ByteOrder GetByteOrder() const =0;
103  virtual void HashEndianCorrectedBlock(const HashWordType *data) =0;
104  virtual size_t HashMultipleBlocks(const T *input, size_t length);
105  void HashBlock(const HashWordType *input)
106  {HashMultipleBlocks(input, this->BlockSize());}
107 
108  virtual T* DataBuf() =0;
109  virtual T* StateBuf() =0;
110 
111 private:
112  T m_countLo, m_countHi;
113 };
114 
115 /// \brief Iterated hash base class
116 /// \tparam T_HashWordType Hash word type
117 /// \tparam T_Endianness Endianness type of hash
118 /// \tparam T_BlockSize Block size of the hash
119 /// \tparam T_Base HashTransformation derived class
120 /// \details IteratedHash provides a default implementation for block-based iterated hashes
121 /// \sa HashTransformation, MessageAuthenticationCode
122 template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, class T_Base = HashTransformation>
123 class CRYPTOPP_NO_VTABLE IteratedHash : public IteratedHashBase<T_HashWordType, T_Base>
124 {
125 public:
126  typedef T_Endianness ByteOrderClass;
127  typedef T_HashWordType HashWordType;
128 
129  CRYPTOPP_CONSTANT(BLOCKSIZE = T_BlockSize)
130  // BCB2006 workaround: can't use BLOCKSIZE here
131  CRYPTOPP_COMPILE_ASSERT((T_BlockSize & (T_BlockSize - 1)) == 0); // blockSize is a power of 2
132 
133  virtual ~IteratedHash() {}
134 
135  /// \brief Provides the block size of the hash
136  /// \return the block size of the hash, in bytes
137  /// \details BlockSize() returns <tt>T_BlockSize</tt>.
138  unsigned int BlockSize() const {return T_BlockSize;}
139 
140  /// \brief Provides the byte order of the hash
141  /// \returns the byte order of the hash as an enumeration
142  /// \details GetByteOrder() returns <tt>T_Endianness::ToEnum()</tt>.
143  /// \sa ByteOrder()
144  ByteOrder GetByteOrder() const {return T_Endianness::ToEnum();}
145 
146  /// \brief Adjusts the byte ordering of the hash
147  /// \param out the output buffer
148  /// \param in the input buffer
149  /// \param byteCount the size of the buffers, in bytes
150  /// \details CorrectEndianess() calls ConditionalByteReverse() using <tt>T_Endianness</tt>.
151  inline void CorrectEndianess(HashWordType *out, const HashWordType *in, size_t byteCount)
152  {
153  CRYPTOPP_ASSERT(in != NULLPTR);
154  CRYPTOPP_ASSERT(out != NULLPTR);
155  CRYPTOPP_ASSERT(IsAligned<T_HashWordType>(in));
156  CRYPTOPP_ASSERT(IsAligned<T_HashWordType>(out));
157 
158  ConditionalByteReverse(T_Endianness::ToEnum(), out, in, byteCount);
159  }
160 
161 protected:
162  T_HashWordType* DataBuf() {return this->m_data;}
163  FixedSizeSecBlock<T_HashWordType, T_BlockSize/sizeof(T_HashWordType)> m_data;
164 };
165 
166 /// \brief Iterated hash with a static transformation function
167 /// \tparam T_HashWordType Hash word type
168 /// \tparam T_Endianness Endianness type of hash
169 /// \tparam T_BlockSize Block size of the hash
170 /// \tparam T_StateSize Internal state size of the hash
171 /// \tparam T_Transform HashTransformation derived class
172 /// \tparam T_DigestSize Digest size of the hash
173 /// \tparam T_StateAligned Flag indicating if state is 16-byte aligned
174 /// \sa HashTransformation, MessageAuthenticationCode
175 template <class T_HashWordType, class T_Endianness, unsigned int T_BlockSize, unsigned int T_StateSize, class T_Transform, unsigned int T_DigestSize = 0, bool T_StateAligned = false>
176 class CRYPTOPP_NO_VTABLE IteratedHashWithStaticTransform
177  : public ClonableImpl<T_Transform, AlgorithmImpl<IteratedHash<T_HashWordType, T_Endianness, T_BlockSize>, T_Transform> >
178 {
179 public:
180  CRYPTOPP_CONSTANT(DIGESTSIZE = T_DigestSize ? T_DigestSize : T_StateSize)
181 
182  virtual ~IteratedHashWithStaticTransform() {}
183 
184  /// \brief Provides the digest size of the hash
185  /// \return the digest size of the hash, in bytes
186  /// \details DigestSize() returns <tt>DIGESTSIZE</tt>.
187  unsigned int DigestSize() const {return DIGESTSIZE;}
188 
189 protected:
190  IteratedHashWithStaticTransform() {this->Init();}
191  void HashEndianCorrectedBlock(const T_HashWordType *data) {T_Transform::Transform(this->m_state, data);}
192  void Init() {T_Transform::InitState(this->m_state);}
193 
194  T_HashWordType* StateBuf() {return this->m_state;}
195  FixedSizeAlignedSecBlock<T_HashWordType, T_BlockSize/sizeof(T_HashWordType), T_StateAligned> m_state;
196 };
197 
198 #if !defined(__GNUC__) && !defined(__clang__)
199  CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word64, HashTransformation>;
200  CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word64, MessageAuthenticationCode>;
201 
202  CRYPTOPP_DLL_TEMPLATE_CLASS IteratedHashBase<word32, HashTransformation>;
203  CRYPTOPP_STATIC_TEMPLATE_CLASS IteratedHashBase<word32, MessageAuthenticationCode>;
204 #endif
205 
206 NAMESPACE_END
207 
208 #if CRYPTOPP_MSC_VERSION
209 # pragma warning(pop)
210 #endif
211 
212 #endif
IteratedHashBase()
Construct an IteratedHashBase.
Definition: iterhash.h:43
Classes providing basic library services.
Utility functions for the Crypto++ library.
ByteOrder
Provides the byte ordering.
Definition: cryptlib.h:143
Base class for identifying alogorithm.
Definition: simple.h:25
Iterated hash with a static transformation function.
Definition: iterhash.h:176
Abstract base classes that provide a uniform interface to this library.
unsigned int BlockSize() const
Provides the block size of the hash.
Definition: iterhash.h:138
Exception thrown when trying to hash more data than is allowed by a hash function.
Definition: iterhash.h:22
Classes and functions for secure memory allocations.
ByteOrder GetByteOrder() const
Provides the byte order of the hash.
Definition: iterhash.h:144
#define CRYPTOPP_COMPILE_ASSERT(expr)
Compile time assertion.
Definition: misc.h:149
T ConditionalByteReverse(ByteOrder order, T value)
Reverses bytes in a value depending upon endianness.
Definition: misc.h:2197
Fixed size stack-based SecBlock with 16-byte alignment.
Definition: secblock.h:1089
void CorrectEndianess(HashWordType *out, const HashWordType *in, size_t byteCount)
Adjusts the byte ordering of the hash.
Definition: iterhash.h:151
unsigned int DigestSize() const
Provides the digest size of the hash.
Definition: iterhash.h:187
Fixed size stack-based SecBlock.
Definition: secblock.h:1077
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:69
const char * BlockSize()
int, in bytes
Definition: argnames.h:27
unsigned int OptimalBlockSize() const
Provides the input block size most efficient for this cipher.
Definition: iterhash.h:50
unsigned int OptimalDataAlignment() const
Provides input and output data alignment for optimal performance.
Definition: iterhash.h:55
Iterated hash base class.
Definition: iterhash.h:35
virtual std::string AlgorithmProvider() const
Retrieve the provider of this algorithm.
Definition: iterhash.h:91
Iterated hash base class.
Definition: iterhash.h:123
Crypto++ library namespace.
Input data was received that did not conform to expected format.
Definition: cryptlib.h:212