Crypto++ 8.7
Free C++ class library of cryptographic schemes
Public Member Functions | List of all members
InvertibleLUCFunction Class Reference

The LUC inverse function. More...

#include <luc.h>

+ Inheritance diagram for InvertibleLUCFunction:

Public Member Functions

void Initialize (RandomNumberGenerator &rng, unsigned int modulusBits, const Integer &eStart=17)
 Create a LUC private key. More...
 
void Initialize (const Integer &n, const Integer &e, const Integer &p, const Integer &q, const Integer &u)
 Initialize a LUC private key with {n,e,p,q,dp,dq,u}. More...
 
void BERDecode (BufferedTransformation &bt)
 
void DEREncode (BufferedTransformation &bt) const
 
Integer CalculateInverse (RandomNumberGenerator &rng, const Integer &x) const
 Calculates the inverse of an element. More...
 
bool Validate (RandomNumberGenerator &rng, unsigned int level) const
 Check this object for errors. More...
 
bool GetVoidValue (const char *name, const std::type_info &valueType, void *pValue) const
 Get a named value. More...
 
void AssignFrom (const NameValuePairs &source)
 Assign values to this object. More...
 
void GenerateRandom (RandomNumberGenerator &rng, const NameValuePairs &alg)
 
const IntegerGetPrime1 () const
 
const IntegerGetPrime2 () const
 
const IntegerGetMultiplicativeInverseOfPrime2ModPrime1 () const
 
void SetPrime1 (const Integer &p)
 
void SetPrime2 (const Integer &q)
 
void SetMultiplicativeInverseOfPrime2ModPrime1 (const Integer &u)
 
- Public Member Functions inherited from LUCFunction
void Initialize (const Integer &n, const Integer &e)
 Initialize a LUC public key with {n,e}. More...
 
void BERDecode (BufferedTransformation &bt)
 
void DEREncode (BufferedTransformation &bt) const
 
Integer ApplyFunction (const Integer &x) const
 Applies the trapdoor. More...
 
Integer PreimageBound () const
 Returns the maximum size of a message before the trapdoor function is applied. More...
 
Integer ImageBound () const
 Returns the maximum size of a representation after the trapdoor function is applied. More...
 
bool Validate (RandomNumberGenerator &rng, unsigned int level) const
 Check this object for errors. More...
 
bool GetVoidValue (const char *name, const std::type_info &valueType, void *pValue) const
 Get a named value. More...
 
void AssignFrom (const NameValuePairs &source)
 Assign values to this object. More...
 
const IntegerGetModulus () const
 
const IntegerGetPublicExponent () const
 
void SetModulus (const Integer &n)
 
void SetPublicExponent (const Integer &e)
 
- Public Member Functions inherited from TrapdoorFunction
Integer ApplyRandomizedFunction (RandomNumberGenerator &rng, const Integer &x) const
 Applies the trapdoor function. More...
 
bool IsRandomized () const
 Determines if the encryption algorithm is randomized. More...
 
virtual Integer ApplyFunction (const Integer &x) const =0
 Applies the trapdoor. More...
 
virtual Integer ApplyRandomizedFunction (RandomNumberGenerator &rng, const Integer &x) const =0
 Applies the trapdoor function, using random data if required. More...
 
virtual bool IsRandomized () const
 Determines if the encryption algorithm is randomized. More...
 
- Public Member Functions inherited from TrapdoorFunctionBounds
virtual Integer PreimageBound () const =0
 Returns the maximum size of a message before the trapdoor function is applied. More...
 
virtual Integer ImageBound () const =0
 Returns the maximum size of a representation after the trapdoor function is applied. More...
 
virtual Integer MaxPreimage () const
 Returns the maximum size of a message before the trapdoor function is applied bound to a public key. More...
 
virtual Integer MaxImage () const
 Returns the maximum size of a representation after the trapdoor function is applied bound to a public key. More...
 
- Public Member Functions inherited from CryptoMaterial
virtual void AssignFrom (const NameValuePairs &source)=0
 Assign values to this object. More...
 
virtual bool Validate (RandomNumberGenerator &rng, unsigned int level) const =0
 Check this object for errors. More...
 
virtual void ThrowIfInvalid (RandomNumberGenerator &rng, unsigned int level) const
 Check this object for errors. More...
 
virtual void Save (BufferedTransformation &bt) const
 Saves a key to a BufferedTransformation. More...
 
virtual void Load (BufferedTransformation &bt)
 Loads a key from a BufferedTransformation. More...
 
virtual bool SupportsPrecomputation () const
 Determines whether the object supports precomputation. More...
 
virtual void Precompute (unsigned int precomputationStorage)
 Perform precomputation. More...
 
virtual void LoadPrecomputation (BufferedTransformation &storedPrecomputation)
 Retrieve previously saved precomputation. More...
 
virtual void SavePrecomputation (BufferedTransformation &storedPrecomputation) const
 Save precomputation for later use. More...
 
void DoQuickSanityCheck () const
 Perform a quick sanity check. More...
 
- Public Member Functions inherited from NameValuePairs
template<class T >
bool GetThisObject (T &object) const
 Get a copy of this object or subobject. More...
 
template<class T >
bool GetThisPointer (T *&ptr) const
 Get a pointer to this object. More...
 
template<class T >
bool GetValue (const char *name, T &value) const
 Get a named value. More...
 
template<class T >
GetValueWithDefault (const char *name, T defaultValue) const
 Get a named value. More...
 
CRYPTOPP_DLL std::string GetValueNames () const
 Get a list of value names that can be retrieved. More...
 
CRYPTOPP_DLL bool GetIntValue (const char *name, int &value) const
 Get a named value with type int. More...
 
CRYPTOPP_DLL int GetIntValueWithDefault (const char *name, int defaultValue) const
 Get a named value with type int, with default. More...
 
CRYPTOPP_DLL bool GetWord64Value (const char *name, word64 &value) const
 Get a named value with type word64. More...
 
CRYPTOPP_DLL word64 GetWord64ValueWithDefault (const char *name, word64 defaultValue) const
 Get a named value with type word64, with default. More...
 
template<class T >
void GetRequiredParameter (const char *className, const char *name, T &value) const
 Retrieves a required name/value pair. More...
 
CRYPTOPP_DLL void GetRequiredIntParameter (const char *className, const char *name, int &value) const
 Retrieves a required name/value pair. More...
 
virtual CRYPTOPP_DLL bool GetVoidValue (const char *name, const std::type_info &valueType, void *pValue) const =0
 Get a named value. More...
 
- Public Member Functions inherited from TrapdoorFunctionInverse
Integer CalculateRandomizedInverse (RandomNumberGenerator &rng, const Integer &x) const
 Applies the inverse of the trapdoor function. More...
 
bool IsRandomized () const
 Determines if the decryption algorithm is randomized. More...
 
virtual Integer CalculateInverse (RandomNumberGenerator &rng, const Integer &x) const =0
 Calculates the inverse of an element. More...
 
virtual Integer CalculateRandomizedInverse (RandomNumberGenerator &rng, const Integer &x) const =0
 Applies the inverse of the trapdoor function, using random data if required. More...
 
virtual bool IsRandomized () const
 Determines if the decryption algorithm is randomized. More...
 
- Public Member Functions inherited from GeneratableCryptoMaterial
virtual void GenerateRandom (RandomNumberGenerator &rng, const NameValuePairs &params=g_nullNameValuePairs)
 Generate a random key or crypto parameters. More...
 
void GenerateRandomWithKeySize (RandomNumberGenerator &rng, unsigned int keySize)
 Generate a random key or crypto parameters. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from NameValuePairs
static CRYPTOPP_DLL void ThrowIfTypeMismatch (const char *name, const std::type_info &stored, const std::type_info &retrieving)
 Ensures an expected name and type is present. More...
 

Detailed Description

The LUC inverse function.

This class is here for historical and pedagogical interest. It has no practical advantages over other trapdoor functions and probably shouldn't be used in production software. The discrete log based LUC schemes defined later in this .h file may be of more practical interest.

Since
Crypto++ 2.1

Definition at line 78 of file luc.h.

Constructor & Destructor Documentation

◆ ~InvertibleLUCFunction()

virtual InvertibleLUCFunction::~InvertibleLUCFunction ( )
inlinevirtual

Definition at line 83 of file luc.h.

Member Function Documentation

◆ Initialize() [1/2]

void InvertibleLUCFunction::Initialize ( RandomNumberGenerator rng,
unsigned int  modulusBits,
const Integer eStart = 17 
)

Create a LUC private key.

Parameters
rnga RandomNumberGenerator derived class
modulusBitsthe size of the modulus, in bits
eStartthe desired starting public exponent

Initialize() creates a new keypair using a starting public exponent of 17.

This function overload of Initialize() creates a new keypair because it takes a RandomNumberGenerator() as a parameter. If you have an existing keypair, then use one of the other Initialize() overloads.

Definition at line 137 of file luc.cpp.

◆ Initialize() [2/2]

void InvertibleLUCFunction::Initialize ( const Integer n,
const Integer e,
const Integer p,
const Integer q,
const Integer u 
)
inline

Initialize a LUC private key with {n,e,p,q,dp,dq,u}.

Parameters
nmodulus
epublic exponent
pfirst prime factor
qsecond prime factor
uq-1 mod p

This Initialize() function overload initializes a private key from existing parameters.

Definition at line 102 of file luc.h.

◆ BERDecode()

void InvertibleLUCFunction::BERDecode ( BufferedTransformation bt)

Definition at line 142 of file luc.cpp.

◆ DEREncode()

void InvertibleLUCFunction::DEREncode ( BufferedTransformation bt) const

Definition at line 158 of file luc.cpp.

◆ CalculateInverse()

Integer InvertibleLUCFunction::CalculateInverse ( RandomNumberGenerator rng,
const Integer x 
) const
virtual

Calculates the inverse of an element.

Parameters
rnga RandomNumberGenerator derived class
xthe element
Returns
the inverse of the element in the group

Implements TrapdoorFunctionInverse.

Definition at line 172 of file luc.cpp.

◆ Validate()

bool InvertibleLUCFunction::Validate ( RandomNumberGenerator rng,
unsigned int  level 
) const
virtual

Check this object for errors.

Parameters
rnga RandomNumberGenerator for objects which use randomized testing
levelthe level of thoroughness
Returns
true if the tests succeed, false otherwise

There are four levels of thoroughness:

  • 0 - using this object won't cause a crash or exception
  • 1 - this object will probably function, and encrypt, sign, other operations correctly
  • 2 - ensure this object will function correctly, and perform reasonable security checks
  • 3 - perform reasonable security checks, and do checks that may take a long time

Level 0 does not require a RandomNumberGenerator. A NullRNG() can be used for level 0. Level 1 may not check for weak keys and such. Levels 2 and 3 are recommended.

See also
ThrowIfInvalid()

Reimplemented from LUCFunction.

Definition at line 180 of file luc.cpp.

◆ GetVoidValue()

bool InvertibleLUCFunction::GetVoidValue ( const char *  name,
const std::type_info &  valueType,
void *  pValue 
) const
virtual

Get a named value.

Parameters
namethe name of the object or value to retrieve
valueTypereference to a variable that receives the value
pValuevoid pointer to a variable that receives the value
Returns
true if the value was retrieved, false otherwise

GetVoidValue() retrieves the value of name if it exists.

Note
GetVoidValue() is an internal function and should be implemented by derived classes. Users should use one of the other functions instead.
See also
GetValue(), GetValueWithDefault(), GetIntValue(), GetIntValueWithDefault(), GetRequiredParameter() and GetRequiredIntParameter()

Reimplemented from LUCFunction.

Definition at line 213 of file luc.cpp.

◆ AssignFrom()

void InvertibleLUCFunction::AssignFrom ( const NameValuePairs source)
virtual

Assign values to this object.

This function can be used to create a public key from a private key.

Reimplemented from LUCFunction.

Definition at line 222 of file luc.cpp.

◆ GenerateRandom()

void InvertibleLUCFunction::GenerateRandom ( RandomNumberGenerator rng,
const NameValuePairs alg 
)
virtual

parameters: (ModulusSize, PublicExponent (default 17))

Reimplemented from GeneratableCryptoMaterial.

Definition at line 114 of file luc.cpp.

◆ GetPrime1()

const Integer & InvertibleLUCFunction::GetPrime1 ( ) const
inline

Definition at line 117 of file luc.h.

◆ GetPrime2()

const Integer & InvertibleLUCFunction::GetPrime2 ( ) const
inline

Definition at line 118 of file luc.h.

◆ GetMultiplicativeInverseOfPrime2ModPrime1()

const Integer & InvertibleLUCFunction::GetMultiplicativeInverseOfPrime2ModPrime1 ( ) const
inline

Definition at line 119 of file luc.h.

◆ SetPrime1()

void InvertibleLUCFunction::SetPrime1 ( const Integer p)
inline

Definition at line 121 of file luc.h.

◆ SetPrime2()

void InvertibleLUCFunction::SetPrime2 ( const Integer q)
inline

Definition at line 122 of file luc.h.

◆ SetMultiplicativeInverseOfPrime2ModPrime1()

void InvertibleLUCFunction::SetMultiplicativeInverseOfPrime2ModPrime1 ( const Integer u)
inline

Definition at line 123 of file luc.h.


The documentation for this class was generated from the following files: