Crypto++  5.6.5
Free C++ class library of cryptographic schemes
Public Member Functions | Static Public Member Functions | List of all members
DL_GroupParameters_IntegerBased Class Referenceabstract

Integer-based GroupParameters specialization. More...

+ Inheritance diagram for DL_GroupParameters_IntegerBased:

Public Member Functions

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)
 
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 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
 
void EncodeElement (bool reversible, const Element &element, byte *encoded) const
 Encodes the element. More...
 
unsigned int GetEncodedElementSize (bool reversible) const
 Retrieves 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
 Retrieves the maximum exponent for the group. More...
 
OID GetAlgorithmID () const
 
virtual const IntegerGetModulus () const =0
 
virtual void SetModulusAndSubgroupGenerator (const Integer &p, const Integer &g)=0
 
void SetSubgroupOrder (const Integer &q)
 
- 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 ElementGetSubgroupGenerator () const
 Retrieves the subgroup generator. More...
 
virtual void SetSubgroupGenerator (const Element &base)
 Set the subgroup generator. More...
 
virtual Element ExponentiateBase (const Integer &exponent) const
 Retrieves the subgroup generator. 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 Integer GetCofactor () const
 Retrieves the cofactor. More...
 
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
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...
 
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...
 
std::string GetValueNames () const
 Get a list of value names that can be retrieved. More...
 
bool GetIntValue (const char *name, int &value) const
 Get a named value with type int. More...
 
int GetIntValueWithDefault (const char *name, int defaultValue) const
 Get a named value with type int, with default. More...
 
template<class T >
void GetRequiredParameter (const char *className, const char *name, T &value) const
 Retrieves a required name/value pair. More...
 
void GetRequiredIntParameter (const char *className, const char *name, int &value) const
 Retrieves a required name/value pair. More...
 

Static Public Member Functions

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

Additional Inherited Members

- Public Types inherited from DL_GroupParameters< Integer >
typedef Integer Element
 

Detailed Description

Integer-based GroupParameters specialization.

Definition at line 33 of file gfpcrypt.h.

Member Function Documentation

void DL_GroupParameters_IntegerBased::Initialize ( const DL_GroupParameters_IntegerBased params)
inline

Initialize a group parameters over integers.

Parameters
paramsthe group parameters

Definition at line 42 of file gfpcrypt.h.

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

Create a group parameters over integers.

Parameters
rnga RandomNumberGenerator derived class
pbitsthe 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 51 of file gfpcrypt.h.

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

Initialize a group parameters over integers.

Parameters
pthe modulus
gthe generator

Definition at line 57 of file gfpcrypt.h.

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

Initialize a group parameters over integers.

Parameters
pthe modulus
qthe subgroup order
gthe generator

Definition at line 64 of file gfpcrypt.h.

void DL_GroupParameters_IntegerBased::BERDecode ( BufferedTransformation bt)
virtual

Decode this object from a BufferedTransformation.

Parameters
btBufferedTransformation object

Uses Basic Encoding Rules (BER)

Implements ASN1Object.

Definition at line 228 of file gfpcrypt.cpp.

void DL_GroupParameters_IntegerBased::DEREncode ( BufferedTransformation bt) const
virtual

Encode this object into a BufferedTransformation.

Parameters
btBufferedTransformation object

Uses Distinguished Encoding Rules (DER)

Implements ASN1Object.

Definition at line 247 of file gfpcrypt.cpp.

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

parameters: (ModulusSize, SubgroupOrderSize (optional))

Reimplemented from GeneratableCryptoMaterial.

Reimplemented in DL_GroupParameters_DSA.

Definition at line 179 of file gfpcrypt.cpp.

bool DL_GroupParameters_IntegerBased::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() retrives 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()

Implements NameValuePairs.

Reimplemented in DL_GroupParameters_LUC, DL_GroupParameters_GFP, DL_GroupParameters_IntegerBasedImpl< GROUP_PRECOMP, BASE_PRECOMP >, DL_GroupParameters_IntegerBasedImpl< DL_GroupPrecomputation_LUC, DL_BasePrecomputation_LUC >, and DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation >.

Definition at line 256 of file gfpcrypt.cpp.

void DL_GroupParameters_IntegerBased::AssignFrom ( const NameValuePairs source)
virtual

Assign values to this object.

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

Implements CryptoMaterial.

Reimplemented in DL_GroupParameters_IntegerBasedImpl< GROUP_PRECOMP, BASE_PRECOMP >, DL_GroupParameters_IntegerBasedImpl< DL_GroupPrecomputation_LUC, DL_BasePrecomputation_LUC >, and DL_GroupParameters_IntegerBasedImpl< ModExpPrecomputation >.

Definition at line 262 of file gfpcrypt.cpp.

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 78 of file gfpcrypt.h.

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 overriden in a derived class.

Reimplemented from DL_GroupParameters< Integer >.

Definition at line 79 of file gfpcrypt.h.

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

Check the group for errors.

Parameters
rngRandomNumberGenerator for objects which use randomized testing
levellevel 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 >.

Reimplemented in DL_GroupParameters_DSA.

Definition at line 129 of file gfpcrypt.cpp.

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

Check the element for errors.

Parameters
levellevel of thoroughness
elementelement to check
precompoptional 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 >.

Definition at line 145 of file gfpcrypt.cpp.

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

Encodes the element.

Parameters
reversibleflag indicating the encoding format
elementreference to the element to encode
encodeddestination byte array for the encoded element

EncodeElement() must be implemented in a derived class.

Precondition
COUNTOF(encoded) == GetEncodedElementSize()

Implements DL_GroupParameters< Integer >.

Definition at line 207 of file gfpcrypt.cpp.

unsigned int DL_GroupParameters_IntegerBased::GetEncodedElementSize ( bool  reversible) const
virtual

Retrieves the encoded element's size.

Parameters
reversibleflag indicating the encoding format
Returns
encoded element's size, in bytes

The format of the encoded element varies by the underlyinhg type of the element and the reversible flag. GetEncodedElementSize() must be implemented in a derived class.

See also
GetEncodedElementSize(), EncodeElement(), DecodeElement()

Implements DL_GroupParameters< Integer >.

Definition at line 213 of file gfpcrypt.cpp.

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

Decodes the element.

Parameters
encodedbyte array with the encoded element
checkForGroupMembershipflag indicating if the element should be validated
Returns
Element after decoding

DecodeElement() must be implemented in a derived class.

Precondition
COUNTOF(encoded) == GetEncodedElementSize()

Implements DL_GroupParameters< Integer >.

Definition at line 219 of file gfpcrypt.cpp.

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

Converts an element to an Integer.

Parameters
elementthe 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 89 of file gfpcrypt.h.

Integer DL_GroupParameters_IntegerBased::GetMaxExponent ( ) const
virtual

Retrieves the maximum exponent for the group.

Returns
the maximum exponent for the group

Implements DL_GroupParameters< Integer >.

Definition at line 292 of file gfpcrypt.cpp.


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