Crypto++  8.6
Free C++ class library of cryptographic schemes
seal.h
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1 // seal.h - originally written and placed in the public domain by Wei Dai
2 
3 /// \file seal.h
4 /// \brief Classes for SEAL stream cipher
5 /// \since Crypto++ 2.2
6 
7 #ifndef CRYPTOPP_SEAL_H
8 #define CRYPTOPP_SEAL_H
9 
10 #include "strciphr.h"
11 #include "secblock.h"
12 
13 NAMESPACE_BEGIN(CryptoPP)
14 
15 /// \brief SEAL stream cipher information
16 /// \tparam B Endianness of the stream cipher
17 /// \since Crypto++ 2.2
18 template <class B = BigEndian>
19 struct SEAL_Info : public FixedKeyLength<20, SimpleKeyingInterface::INTERNALLY_GENERATED_IV, 4>
20 {
21  CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return B::ToEnum() == LITTLE_ENDIAN_ORDER ? "SEAL-3.0-LE" : "SEAL-3.0-BE";}
22 };
23 
24 /// \brief SEAL stream cipher operation
25 /// \tparam B Endianness of the stream cipher
26 /// \since Crypto++ 2.2
27 template <class B = BigEndian>
28 class CRYPTOPP_NO_VTABLE SEAL_Policy : public AdditiveCipherConcretePolicy<word32, 256>, public SEAL_Info<B>
29 {
30 protected:
31  void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length);
32  void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount);
33  void CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length);
34  bool CipherIsRandomAccess() const {return true;}
35  void SeekToIteration(lword iterationCount);
36 
37 private:
40  SecBlock<word32> m_R;
41 
42  word32 m_startCount, m_iterationsPerCount;
43  word32 m_outsideCounter, m_insideCounter;
44 };
45 
46 /// \brief SEAL stream cipher
47 /// \tparam B Endianness of the stream cipher
48 /// \sa <a href="http://www.cryptopp.com/wiki/SEAL-3.0-BE">SEAL</a>
49 /// \since Crypto++ 2.2
50 template <class B = BigEndian>
51 struct SEAL : public SEAL_Info<B>, public SymmetricCipherDocumentation
52 {
54  typedef Encryption Decryption;
55 };
56 
57 NAMESPACE_END
58 
59 #endif
AdditiveCipherAbstractPolicy::CipherIsRandomAccess
virtual bool CipherIsRandomAccess() const =0
Flag indicating random access.
AdditiveCipherAbstractPolicy::CipherResynchronize
virtual void CipherResynchronize(byte *keystreamBuffer, const byte *iv, size_t length)
Resynchronize the cipher.
Definition: strciphr.h:163
SymmetricCipherDocumentation
Provides Encryption and Decryption typedefs used by derived classes to implement a symmetric cipher.
Definition: seckey.h:413
SymmetricCipherFinal
SymmetricCipher implementation.
Definition: strciphr.h:674
AdditiveCipherConcretePolicy
Base class for additive stream ciphers.
Definition: strciphr.h:201
AdditiveCipherAbstractPolicy::CipherSetKey
virtual void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length)=0
Key the cipher.
secblock.h
Classes and functions for secure memory allocations.
LITTLE_ENDIAN_ORDER
@ LITTLE_ENDIAN_ORDER
byte order is little-endian
Definition: cryptlib.h:145
word32
unsigned int word32
32-bit unsigned datatype
Definition: config_int.h:62
SEAL_Info
SEAL stream cipher information.
Definition: seal.h:19
FixedKeyLength
Inherited by keyed algorithms with fixed key length.
Definition: seckey.h:124
AdditiveCipherTemplate<>
KeystreamOperation
KeystreamOperation
Keystream operation flags.
Definition: strciphr.h:88
SEAL
SEAL stream cipher.
Definition: seal.h:51
FixedSizeSecBlock< word32, 512 >
lword
word64 lword
Large word type.
Definition: config_int.h:158
CryptoPP
Crypto++ library namespace.
AdditiveCipherAbstractPolicy::SeekToIteration
virtual void SeekToIteration(lword iterationCount)
Seeks to a random position in the stream.
Definition: strciphr.h:174
SEAL_Policy
SEAL stream cipher operation.
Definition: seal.h:28
SecBlock< word32 >
AdditiveCipherConcretePolicy::OperateKeystream
virtual void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount)=0
Operates the keystream.
NameValuePairs
Interface for retrieving values given their names.
Definition: cryptlib.h:321
strciphr.h
Classes for implementing stream ciphers.