Integer-based GroupParameters specialization. More...

#include <gfpcrypt.h>

Inheritance diagram for DL_GroupParameters_IntegerBased:

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

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

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

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

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

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

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

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

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

const Integer &	GetSubgroupOrder () const
	Retrieves the subgroup order.

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

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

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

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

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

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

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

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

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

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

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

virtual void	SetModulusAndSubgroupGenerator (const Integer &p, const Integer &g)=0
	Set group parameters.

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

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

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

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

Public Member Functions inherited from DL_GroupParameters< Integer >
bool	Validate (RandomNumberGenerator &rng, unsigned int level) const
	Check this object for errors.

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

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

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

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

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

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

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

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

virtual const DL_GroupPrecomputation< Element > &	GetGroupPrecomputation () const=0
	Retrieves the group precomputation.

virtual const DL_FixedBasePrecomputation< Element > &	GetBasePrecomputation () const=0
	Retrieves the group precomputation.

virtual DL_FixedBasePrecomputation< Element > &	AccessBasePrecomputation ()=0
	Retrieves the group precomputation.

virtual Integer	GetCofactor () const
	Retrieves the cofactor.

virtual bool	IsIdentity (const Element &element) const=0
	Determines if an element is an identity.

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

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

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

void	DoQuickSanityCheck () const
	Perform a quick sanity check.

Public Member Functions inherited from NameValuePairs
template<class T >
bool	GetThisObject (T &object) const
	Get a copy of this object or subobject.

template<class T >
bool	GetThisPointer (T *&ptr) const
	Get a pointer to this object.

template<class T >
bool	GetValue (const char *name, T &value) const
	Get a named value.

template<class T >
T	GetValueWithDefault (const char *name, T defaultValue) const
	Get a named value.

CRYPTOPP_DLL std::string	GetValueNames () const
	Get a list of value names that can be retrieved.

CRYPTOPP_DLL bool	GetIntValue (const char *name, int &value) const
	Get a named value with type int.

CRYPTOPP_DLL int	GetIntValueWithDefault (const char *name, int defaultValue) const
	Get a named value with type int, with default.

CRYPTOPP_DLL bool	GetWord64Value (const char *name, word64 &value) const
	Get a named value with type word64.

CRYPTOPP_DLL word64	GetWord64ValueWithDefault (const char *name, word64 defaultValue) const
	Get a named value with type word64, with default.

template<class T >
void	GetRequiredParameter (const char className, const char name, T &value) const
	Retrieves a required name/value pair.

CRYPTOPP_DLL void	GetRequiredIntParameter (const char className, const char name, int &value) const
	Retrieves a required name/value pair.

Static Public Member Functions
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.

Additional Inherited Members
Public Types inherited from DL_GroupParameters< Integer >
typedef Integer	Element

Detailed Description

Integer-based GroupParameters specialization.

Definition at line 34 of file gfpcrypt.h.

Constructor & Destructor Documentation

◆ ~DL_GroupParameters_IntegerBased()

virtual DL_GroupParameters_IntegerBased::~DL_GroupParameters_IntegerBased ( )

inlinevirtual

Definition at line 39 of file gfpcrypt.h.

Member Function Documentation

◆ Initialize() [1/4]

void DL_GroupParameters_IntegerBased::Initialize ( const DL_GroupParameters_IntegerBased & params )

inline

Initialize a group parameters over integers.

Parameters

params the group parameters

Definition at line 43 of file gfpcrypt.h.

◆ Initialize() [2/4]

void DL_GroupParameters_IntegerBased::Initialize	(	RandomNumberGenerator &	rng,
		unsigned int	pbits )

inline

Create a group parameters over integers.

Parameters

rng	a RandomNumberGenerator derived class
pbits	the size of p, in bits

This function overload of Initialize() creates a new private key 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 52 of file gfpcrypt.h.

◆ Initialize() [3/4]

void DL_GroupParameters_IntegerBased::Initialize	(	const Integer &	p,
		const Integer &	g )

inline

Initialize a group parameters over integers.

Parameters

p	the modulus
g	the generator

Definition at line 58 of file gfpcrypt.h.

◆ Initialize() [4/4]

void DL_GroupParameters_IntegerBased::Initialize	(	const Integer &	p,
		const Integer &	q,
		const Integer &	g )

inline

Initialize a group parameters over integers.

Parameters

p	the modulus
q	the subgroup order
g	the generator

Definition at line 65 of file gfpcrypt.h.

◆ BERDecode()

void DL_GroupParameters_IntegerBased::BERDecode ( BufferedTransformation & bt )

virtual

Decode this object from a BufferedTransformation.

Parameters

bt	BufferedTransformation object

Uses Basic Encoding Rules (BER)

Implements ASN1Object.

◆ DEREncode()

void DL_GroupParameters_IntegerBased::DEREncode ( BufferedTransformation & bt ) const

virtual

Encode this object into a BufferedTransformation.

Parameters

bt	BufferedTransformation object

Uses Distinguished Encoding Rules (DER)

Implements ASN1Object.

◆ GenerateRandom()

void DL_GroupParameters_IntegerBased::GenerateRandom	(	RandomNumberGenerator &	rng,
		const NameValuePairs &	alg )

virtual

Generate a random key.

Parameters

rng	a RandomNumberGenerator to produce keying material
alg	additional initialization parameters

Recognised NameValuePairs are ModulusSize and SubgroupOrderSize (optional)

Exceptions

KeyingErr if a key can't be generated or algorithm parameters are invalid

Reimplemented from GeneratableCryptoMaterial.

◆ GetVoidValue()

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

virtual

Get a named value.

Parameters

name	the name of the object or value to retrieve
valueType	reference to a variable that receives the value
pValue	void 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 DL_GroupParameters< Integer >.

◆ AssignFrom()

void DL_GroupParameters_IntegerBased::AssignFrom ( const NameValuePairs & source )

virtual

Initialize or reinitialize this key.

Parameters

source NameValuePairs to assign

Implements CryptoMaterial.

◆ GetSubgroupOrder()

const Integer & DL_GroupParameters_IntegerBased::GetSubgroupOrder ( ) const

inlinevirtual

Retrieves the subgroup order.

Returns: the order of subgroup generated by the base element

Implements DL_GroupParameters< Integer >.

Definition at line 98 of file gfpcrypt.h.

◆ GetGroupOrder()

Integer DL_GroupParameters_IntegerBased::GetGroupOrder ( ) const

inlinevirtual

Retrieves the order of the group.

Returns: the order of the group

Either GetGroupOrder() or GetCofactor() must be overridden in a derived class.

Reimplemented from DL_GroupParameters< Integer >.

Definition at line 99 of file gfpcrypt.h.

◆ ValidateGroup()

bool DL_GroupParameters_IntegerBased::ValidateGroup	(	RandomNumberGenerator &	rng,
		unsigned int	level ) const

virtual

Check the group for errors.

Parameters

rng	RandomNumberGenerator for objects which use randomized testing
level	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.

ValidateGroup() must be implemented in a derived class.

Implements DL_GroupParameters< Integer >.

◆ ValidateElement()

bool DL_GroupParameters_IntegerBased::ValidateElement	(	unsigned int	level,
		const Integer &	element,
		const DL_FixedBasePrecomputation< Integer > *	precomp ) const

virtual

Check the element for errors.

Parameters

level	level of thoroughness
element	element to check
precomp	optional pointer to DL_FixedBasePrecomputation

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 performs group membership checks. Level 1 may not check for weak keys and such. Levels 2 and 3 are recommended.

ValidateElement() must be implemented in a derived class.

Implements DL_GroupParameters< Integer >.

◆ FastSubgroupCheckAvailable()

bool DL_GroupParameters_IntegerBased::FastSubgroupCheckAvailable ( ) const

inlinevirtual

Determine if subgroup membership check is fast.

Returns: true or false

Implements DL_GroupParameters< Integer >.

Definition at line 105 of file gfpcrypt.h.

◆ EncodeElement()

void DL_GroupParameters_IntegerBased::EncodeElement	(	bool	reversible,
		const Element &	element,
		byte *	encoded ) const

virtual

Encodes the element.

Parameters

reversible	flag indicating the encoding format
element	reference to the element to encode
encoded	destination byte array for the encoded element

EncodeElement() must be implemented in a derived class.

Precondition: COUNTOF(encoded) == GetEncodedElementSize()

See also: GetEncodedElementSize(), DecodeElement(), Cygwin i386 crash at -O3

Implements DL_GroupParameters< Integer >.

◆ GetEncodedElementSize()

unsigned int DL_GroupParameters_IntegerBased::GetEncodedElementSize ( bool reversible ) const

virtual

Retrieve the encoded element's size.

Parameters

reversible flag indicating the encoding format

Returns: encoded element's size, in bytes

The format of the encoded element varies by the underlying type of the element and the reversible flag.

See also: EncodeElement(), DecodeElement()

Implements DL_GroupParameters< Integer >.

◆ DecodeElement()

Integer DL_GroupParameters_IntegerBased::DecodeElement	(	const byte *	encoded,
		bool	checkForGroupMembership ) const

virtual

Decodes the element.

Parameters

encoded	byte array with the encoded element
checkForGroupMembership	flag indicating if the element should be validated

Returns: Element after decoding

DecodeElement() must be implemented in a derived class.

Precondition: COUNTOF(encoded) == GetEncodedElementSize()

See also: GetEncodedElementSize(), EncodeElement()

Implements DL_GroupParameters< Integer >.

◆ ConvertElementToInteger()

Integer DL_GroupParameters_IntegerBased::ConvertElementToInteger ( const Element & element ) const

inlinevirtual

Converts an element to an Integer.

Parameters

element the element to convert to an Integer

Returns: Element after converting to an Integer

ConvertElementToInteger() must be implemented in a derived class.

Implements DL_GroupParameters< Integer >.

Definition at line 139 of file gfpcrypt.h.

◆ GetMaxExponent()

Integer DL_GroupParameters_IntegerBased::GetMaxExponent ( ) const

virtual

Retrieve the maximum exponent for the group.

Returns: the maximum exponent for the group

Implements DL_GroupParameters< Integer >.

◆ GetAlgorithmID()

OID DL_GroupParameters_IntegerBased::GetAlgorithmID ( ) const

Retrieve the OID of the algorithm.

Returns: OID of the algorithm

◆ GetModulus()

virtual const Integer & DL_GroupParameters_IntegerBased::GetModulus ( ) const

pure virtual

Retrieve the modulus for the group.

Returns: the modulus for the group

◆ SetModulusAndSubgroupGenerator()

virtual void DL_GroupParameters_IntegerBased::SetModulusAndSubgroupGenerator	(	const Integer &	p,
		const Integer &	g )

pure virtual

Set group parameters.

Parameters

p	the prime modulus
g	the group generator

◆ SetSubgroupOrder()

void DL_GroupParameters_IntegerBased::SetSubgroupOrder ( const Integer & q )

inline

Set subgroup order.

Parameters

q	the subgroup order

Definition at line 161 of file gfpcrypt.h.

◆ StaticAlgorithmNamePrefix()

static std::string DL_GroupParameters_IntegerBased::StaticAlgorithmNamePrefix ( )

inlinestatic

Definition at line 164 of file gfpcrypt.h.

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

gfpcrypt.h

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ~DL_GroupParameters_IntegerBased()

Member Function Documentation

◆ Initialize() [1/4]

◆ Initialize() [2/4]

◆ Initialize() [3/4]

◆ Initialize() [4/4]

◆ BERDecode()

◆ DEREncode()

◆ GenerateRandom()

◆ GetVoidValue()

◆ AssignFrom()

◆ GetSubgroupOrder()

◆ GetGroupOrder()

◆ ValidateGroup()

◆ ValidateElement()

◆ FastSubgroupCheckAvailable()

◆ EncodeElement()

◆ GetEncodedElementSize()

◆ DecodeElement()

◆ ConvertElementToInteger()

◆ GetMaxExponent()

◆ GetAlgorithmID()

◆ GetModulus()

◆ SetModulusAndSubgroupGenerator()

◆ SetSubgroupOrder()

◆ StaticAlgorithmNamePrefix()