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

ElGamal encryption for safe interop. More...

#include <gfpcrypt.h>

+ 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 GROUP_PRECOMP::Element Element
 
- Public Types inherited from DL_GroupParametersImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename GROUP_PRECOMP::Element >, DL_GroupParameters_IntegerBased >
typedef ModExpPrecomputation GroupPrecomputation
 
typedef GROUP_PRECOMP::Element Element
 
typedef DL_FixedBasePrecomputationImpl< typename GROUP_PRECOMP::Element > BasePrecomputation
 
- Public Types inherited from DL_GroupParameters< Integer >
typedef Integer Element
 

Public Member Functions

Integer GetMaxExponent () const
 Retrieve the maximum exponent for the group. More...
 
- 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
 Retrieves the group precomputation. More...
 
DL_FixedBasePrecomputation< Element > & AccessBasePrecomputation ()
 Retrieves the group precomputation. More...
 
const IntegerGetModulus () const
 Retrieve the modulus for the group. More...
 
const IntegerGetGenerator () 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 GROUP_PRECOMP::Element > > &rhs) const
 
bool operator!= (const DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename GROUP_PRECOMP::Element > > &rhs) const
 
- Public Member Functions inherited from DL_GroupParametersImpl< ModExpPrecomputation, DL_FixedBasePrecomputationImpl< typename GROUP_PRECOMP::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...
 
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 IntegerGetSubgroupOrder () const
 Retrieves the subgroup order. More...
 
Integer GetGroupOrder () const
 Retrieves the order of the group. More...
 
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 IntegerGetModulus () const =0
 Retrieve the modulus for the group. More...
 
virtual void SetModulusAndSubgroupGenerator (const Integer &p, const Integer &g)=0
 Set group parameters. 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 BERDecode (BufferedTransformation &bt)=0
 Decode this object from a BufferedTransformation. More...
 
virtual void DEREncode (BufferedTransformation &bt) const =0
 Encode this object into a BufferedTransformation. More...
 
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 ElementGetSubgroupGenerator () 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 DL_GroupPrecomputation< Element > & GetGroupPrecomputation () const=0
 Retrieves the group precomputation. More...
 
virtual const DL_FixedBasePrecomputation< Element > & GetBasePrecomputation () const=0
 Retrieves the group precomputation. More...
 
virtual DL_FixedBasePrecomputation< Element > & AccessBasePrecomputation ()=0
 Retrieves the group precomputation. More...
 
virtual const IntegerGetSubgroupOrder () 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 unsigned int GetEncodedElementSize (bool reversible) const=0
 Retrieves the encoded element's size. More...
 
virtual void EncodeElement (bool reversible, const Element &element, byte *encoded) const=0
 Encodes the element. More...
 
virtual Element DecodeElement (const byte *encoded, bool checkForGroupMembership) const=0
 Decodes the element. More...
 
virtual Integer ConvertElementToInteger (const Element &element) const=0
 Converts an element to an Integer. More...
 
virtual bool ValidateGroup (RandomNumberGenerator &rng, unsigned int level) const=0
 Check the group for errors. More...
 
virtual bool ValidateElement (unsigned int level, const Element &element, const DL_FixedBasePrecomputation< Element > *precomp) const=0
 Check the element for errors. More...
 
virtual bool FastSubgroupCheckAvailable () const=0
 
virtual bool IsIdentity (const Element &element) const=0
 Determines if an element is an identity. More...
 
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
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...
 
- 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...
 

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.

Member Typedef Documentation

◆ DefaultCofactorOption

Definition at line 294 of file gfpcrypt.h.

Constructor & Destructor Documentation

◆ ~DL_GroupParameters_ElGamal()

virtual DL_GroupParameters_ElGamal::~DL_GroupParameters_ElGamal ( )
inlinevirtual

Definition at line 296 of file gfpcrypt.h.

Member Function Documentation

◆ GetMaxExponent()

Integer DL_GroupParameters_ElGamal::GetMaxExponent ( ) const
inlinevirtual

Retrieve the maximum exponent for the group.

Returns
the maximum exponent for the group

Reimplemented from DL_GroupParameters_IntegerBased.

Definition at line 298 of file gfpcrypt.h.


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