ElGamal encryption for safe interop. More...

Inheritance diagram for DL_GroupParameters_ElGamal:

Public Types
typedef NoCofactorMultiplication	DefaultCofactorOption

Public Types inherited from DL_GroupParameters_GFP_DefaultSafePrime
typedef NoCofactorMultiplication	DefaultCofactorOption

Public Types inherited from DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation >
typedef ModExpPrecomputation ::Element	Element

Public Types inherited from DL_GroupParametersImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename ModExpPrecomputation ::Element >, DL_GroupParameters_IntegerBased >
typedef ModExpPrecomputation	GroupPrecomputation

typedef ModExpPrecomputation ::Element	Element

typedef DL_FixedBasePrecomputationImpl< typename ModExpPrecomputation ::Element >	BasePrecomputation

Public Types inherited from DL_GroupParameters< Integer >
typedef Integer	Element

Public Member Functions
Integer	GetMaxExponent () const

Public Member Functions inherited from DL_GroupParameters_GFP
bool	IsIdentity (const Integer &element) const
	Determines if an element is an identity. More...

void	SimultaneousExponentiate (Element results, const Element &base, const Integer exponents, unsigned int exponentsCount) const
	Exponentiates a base to multiple exponents. More...

bool	GetVoidValue (const char name, const std::type_info &valueType, void pValue) const
	Get a named value. More...

Element	MultiplyElements (const Element &a, const Element &b) const

Element	CascadeExponentiate (const Element &element1, const Integer &exponent1, const Element &element2, const Integer &exponent2) const

Public Member Functions inherited from DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation >
bool	GetVoidValue (const char name, const std::type_info &valueType, void pValue) const
	Get a named value. More...

void	AssignFrom (const NameValuePairs &source)
	Initialize or reinitialize this key. More...

const DL_FixedBasePrecomputation< Element > &	GetBasePrecomputation () const

DL_FixedBasePrecomputation< Element > &	AccessBasePrecomputation ()
	Retrieves the group precomputation. More...

const Integer &	GetModulus () const
	Retrieve the modulus for the group. More...

const Integer &	GetGenerator () const
	Retrieves a reference to the group generator. More...

void	SetModulusAndSubgroupGenerator (const Integer &p, const Integer &g)
	Set group parameters. More...

bool	operator== (const DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename ModExpPrecomputation ::Element > > &rhs) const

bool	operator!= (const DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename ModExpPrecomputation ::Element > > &rhs) const

Public Member Functions inherited from DL_GroupParametersImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename ModExpPrecomputation ::Element >, DL_GroupParameters_IntegerBased >
const DL_GroupPrecomputation< Element > &	GetGroupPrecomputation () const
	Retrieves the group precomputation. More...

const DL_FixedBasePrecomputation< Element > &	GetBasePrecomputation () const
	Retrieves the group precomputation. More...

DL_FixedBasePrecomputation< Element > &	AccessBasePrecomputation ()
	Retrieves the group precomputation. More...

Public Member Functions inherited from DL_GroupParameters_IntegerBased
void	Initialize (const DL_GroupParameters_IntegerBased &params)
	Initialize a group parameters over integers. More...

void	Initialize (RandomNumberGenerator &rng, unsigned int pbits)
	Create a group parameters over integers. More...

void	Initialize (const Integer &p, const Integer &g)
	Initialize a group parameters over integers. More...

void	Initialize (const Integer &p, const Integer &q, const Integer &g)
	Initialize a group parameters over integers. More...

void	BERDecode (BufferedTransformation &bt)
	Decode this object from a BufferedTransformation. More...

void	DEREncode (BufferedTransformation &bt) const
	Encode this object into a BufferedTransformation. More...

void	GenerateRandom (RandomNumberGenerator &rng, const NameValuePairs &alg)
	Generate a random key. More...

const Integer &	GetSubgroupOrder () const

Integer	GetGroupOrder () const

bool	ValidateGroup (RandomNumberGenerator &rng, unsigned int level) const
	Check the group for errors. More...

bool	ValidateElement (unsigned int level, const Integer &element, const DL_FixedBasePrecomputation< Integer > *precomp) const
	Check the element for errors. More...

bool	FastSubgroupCheckAvailable () const
	Determine if subgroup membership check is fast. More...

void	EncodeElement (bool reversible, const Element &element, byte *encoded) const
	Encodes the element. More...

unsigned int	GetEncodedElementSize (bool reversible) const
	Retrieve the encoded element's size. More...

Integer	DecodeElement (const byte *encoded, bool checkForGroupMembership) const
	Decodes the element. More...

Integer	ConvertElementToInteger (const Element &element) const
	Converts an element to an Integer. More...

Integer	GetMaxExponent () const
	Retrieve the maximum exponent for the group. More...

OID	GetAlgorithmID () const
	Retrieve the OID of the algorithm. More...

virtual const Integer &	GetModulus () const =0
	Retrieve the modulus for the group. More...

void	SetSubgroupOrder (const Integer &q)
	Set subgroup order. More...

Public Member Functions inherited from ASN1CryptoMaterial< DL_GroupParameters< Integer > >
void	Save (BufferedTransformation &bt) const
	DER encode ASN.1 object. More...

void	Load (BufferedTransformation &bt)
	BER decode ASN.1 object. More...

Public Member Functions inherited from ASN1Object
virtual void	BEREncode (BufferedTransformation &bt) const
	Encode this object into a BufferedTransformation. More...

Public Member Functions inherited from DL_GroupParameters< Integer >
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...

bool	SupportsPrecomputation () const
	Determines whether the object supports precomputation. More...

void	Precompute (unsigned int precomputationStorage=16)
	Perform precomputation. More...

void	LoadPrecomputation (BufferedTransformation &storedPrecomputation)
	Retrieve previously saved precomputation. More...

void	SavePrecomputation (BufferedTransformation &storedPrecomputation) const
	Save precomputation for later use. More...

virtual const Element &	GetSubgroupGenerator () const
	Retrieves the subgroup generator. More...

virtual void	SetSubgroupGenerator (const Element &base)
	Sets the subgroup generator. More...

virtual Element	ExponentiateBase (const Integer &exponent) const
	Exponentiates the base. More...

virtual Element	ExponentiateElement (const Element &base, const Integer &exponent) const
	Exponentiates an element. More...

virtual const Integer &	GetSubgroupOrder () const=0
	Retrieves the subgroup order. More...

virtual Integer	GetMaxExponent () const=0
	Retrieves the maximum exponent for the group. More...

virtual Integer	GetGroupOrder () const
	Retrieves the order of the group. More...

virtual Integer	GetCofactor () const
	Retrieves the cofactor. More...

virtual bool	FastSubgroupCheckAvailable () const=0

virtual void	SimultaneousExponentiate (Element results, const Element &base, const Integer exponents, unsigned int exponentsCount) const=0
	Exponentiates a base to multiple exponents. More...

Public Member Functions inherited from GeneratableCryptoMaterial
void	GenerateRandomWithKeySize (RandomNumberGenerator &rng, unsigned int keySize)
	Generate a random key or crypto parameters. More...

Public Member Functions inherited from CryptoMaterial
virtual void	ThrowIfInvalid (RandomNumberGenerator &rng, unsigned int level) const
	Check this object for errors. More...

virtual bool	SupportsPrecomputation () const
	Determines whether the object supports precomputation. 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 >
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...

Additional Inherited Members
Static Public Member Functions inherited from DL_GroupParameters_IntegerBased
static std::string	StaticAlgorithmNamePrefix ()

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

ElGamal encryption for safe interop.

See also: On the (in)security of ElGamal in OpenPGP, Issue 1059, CVE-2021-40530

Since: Crypto++ 8.6

Definition at line 291 of file gfpcrypt.h.

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

gfpcrypt.h

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description