Crypto++ 8.2
Free C&
salsa.h
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1// salsa.h - originally written and placed in the public domain by Wei Dai
2
3/// \file salsa.h
4/// \brief Classes for Salsa and Salsa20 stream ciphers
5
6#ifndef CRYPTOPP_SALSA_H
7#define CRYPTOPP_SALSA_H
8
9#include "strciphr.h"
10#include "secblock.h"
11
12// Clang 3.3 integrated assembler crash on Linux. Clang 3.4 due to compiler
13// error with .intel_syntax, http://llvm.org/bugs/show_bug.cgi?id=24232
14#if CRYPTOPP_BOOL_X32 || defined(CRYPTOPP_DISABLE_MIXED_ASM)
15# define CRYPTOPP_DISABLE_SALSA_ASM 1
16#endif
17
18NAMESPACE_BEGIN(CryptoPP)
19
20/// \brief Salsa20 core transform
21/// \param data the data to transform
22/// \param rounds the number of rounds
23/// \details Several algorithms, like CryptoBox and Scrypt, require access to
24/// the core Salsa20 transform. The current Crypto++ implementation does not
25/// lend itself to disgorging the Salsa20 cipher from the Salsa20 core transform.
26/// Instead Salsa20_Core is provided with customary accelerations.
27void Salsa20_Core(word32* data, unsigned int rounds);
28
29/// \brief Salsa20 stream cipher information
30struct Salsa20_Info : public VariableKeyLength<32, 16, 32, 16, SimpleKeyingInterface::UNIQUE_IV, 8>
31{
32 static std::string StaticAlgorithmName() {return "Salsa20";}
33};
34
35/// \brief Salsa20 stream cipher operation
36class CRYPTOPP_NO_VTABLE Salsa20_Policy : public AdditiveCipherConcretePolicy<word32, 16>
37{
38protected:
39 Salsa20_Policy() : m_rounds(ROUNDS) {}
40 void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length);
41 void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount);
42 void CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length);
43 bool CipherIsRandomAccess() const {return true;}
44 void SeekToIteration(lword iterationCount);
45
46#if (CRYPTOPP_BOOL_X86 || CRYPTOPP_BOOL_X32 || CRYPTOPP_BOOL_X64)
47 unsigned int GetAlignment() const;
48 unsigned int GetOptimalBlockSize() const;
49#endif
50
51 std::string AlgorithmProvider() const;
52
53 CRYPTOPP_CONSTANT(ROUNDS = 20) // Default rounds
55 int m_rounds;
56};
57
58/// \brief Salsa20 stream cipher
59/// \details Salsa20 provides a variable number of rounds: 8, 12 or 20. The default number of rounds is 20.
60/// \sa <a href="http://www.cryptolounge.org/wiki/XSalsa20">XSalsa20</a>
62{
64 typedef Encryption Decryption;
65};
66
67/// \brief XSalsa20 stream cipher information
68struct XSalsa20_Info : public FixedKeyLength<32, SimpleKeyingInterface::UNIQUE_IV, 24>
69{
70 static std::string StaticAlgorithmName() {return "XSalsa20";}
71};
72
73/// \brief XSalsa20 stream cipher operation
74class CRYPTOPP_NO_VTABLE XSalsa20_Policy : public Salsa20_Policy
75{
76public:
77 void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length);
78 void CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length);
79
80protected:
82};
83
84/// \brief XSalsa20 stream cipher
85/// \details XSalsa20 provides a variable number of rounds: 8, 12 or 20. The default number of rounds is 20.
86/// \sa <a href="http://www.cryptolounge.org/wiki/XSalsa20">XSalsa20</a>
88{
90 typedef Encryption Decryption;
91};
92
93NAMESPACE_END
94
95#endif
Inherited by keyed algorithms with fixed key length.
Definition: seckey.h:125
Fixed size stack-based SecBlock with 16-byte alignment.
Definition: secblock.h:1090
Fixed size stack-based SecBlock.
Definition: secblock.h:1078
Interface for retrieving values given their names.
Definition: cryptlib.h:294
Salsa20 stream cipher operation.
Definition: salsa.h:37
SymmetricCipher implementation.
Definition: strciphr.h:674
Inherited by keyed algorithms with variable key length.
Definition: seckey.h:166
XSalsa20 stream cipher operation.
Definition: salsa.h:75
Crypto++ library namespace.
void Salsa20_Core(word32 *data, unsigned int rounds)
Salsa20 core transform.
Definition: salsa.cpp:39
Classes and functions for secure memory allocations.
Classes for implementing stream ciphers.
KeystreamOperation
Keystream operation flags.
Definition: strciphr.h:88
virtual std::string AlgorithmProvider() const
Retrieve the provider of this algorithm.
Definition: strciphr.h:192
virtual unsigned int GetOptimalBlockSize() const
Provides number of ideal bytes to process.
Definition: strciphr.h:123
virtual void SeekToIteration(lword iterationCount)
Seeks to a random position in the stream.
Definition: strciphr.h:174
virtual void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length)=0
Key the cipher.
virtual bool CipherIsRandomAccess() const =0
Flag indicating random access.
virtual void CipherResynchronize(byte *keystreamBuffer, const byte *iv, size_t length)
Resynchronize the cipher.
Definition: strciphr.h:163
Base class for additive stream ciphers.
Definition: strciphr.h:202
unsigned int GetAlignment() const
Provides data alignment requirements.
Definition: strciphr.h:221
virtual void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount)=0
Operates the keystream.
Salsa20 stream cipher information.
Definition: salsa.h:31
Salsa20 stream cipher.
Definition: salsa.h:62
Provides Encryption and Decryption typedefs used by derived classes to implement a symmetric cipher.
Definition: seckey.h:414
XSalsa20 stream cipher information.
Definition: salsa.h:69
XSalsa20 stream cipher.
Definition: salsa.h:88