Crypto++
Public Types | Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
DL_GroupParameters_EC< EC > Class Template Referenceabstract

Elliptic Curve Parameters. More...

#include <eccrypto.h>

Inheritance diagram for DL_GroupParameters_EC< EC >:
DL_GroupParametersImpl< EcPrecomputation< EC > > DL_GroupParameters< typenameEcPrecomputation< EC >::Element > CryptoParameters GeneratableCryptoMaterial CryptoMaterial NameValuePairs

Public Types

typedef EC EllipticCurve
 
typedef EllipticCurve::Point Point
 
typedef Point Element
 
typedef
IncompatibleCofactorMultiplication 
DefaultCofactorOption
 
typedef EcPrecomputation< EC > GroupPrecomputation
 
typedef
DL_FixedBasePrecomputationImpl
< typenameEcPrecomputation< EC >
::Element > 
BasePrecomputation
 

Public Member Functions

 DL_GroupParameters_EC (const OID &oid)
 
 DL_GroupParameters_EC (const EllipticCurve &ec, const Point &G, const Integer &n, const Integer &k=Integer::Zero())
 
 DL_GroupParameters_EC (BufferedTransformation &bt)
 
void Initialize (const EllipticCurve &ec, const Point &G, const Integer &n, const Integer &k=Integer::Zero())
 
void Initialize (const OID &oid)
 
bool GetVoidValue (const char *name, const std::type_info &valueType, void *pValue) const
 to be implemented by derived classes, users should use one of the above functions instead
 
void AssignFrom (const NameValuePairs &source)
 assign values from source to this object More...
 
void GenerateRandom (RandomNumberGenerator &rng, const NameValuePairs &alg)
 this implementation doesn't actually generate a curve, it just initializes the parameters with existing values More...
 
const
DL_FixedBasePrecomputation
< Element > & 
GetBasePrecomputation () const
 
DL_FixedBasePrecomputation
< Element > & 
AccessBasePrecomputation ()
 
const IntegerGetSubgroupOrder () const
 
Integer GetCofactor () const
 
bool ValidateGroup (RandomNumberGenerator &rng, unsigned int level) const
 
bool ValidateElement (unsigned int level, const Element &element, const DL_FixedBasePrecomputation< Element > *precomp) const
 
bool FastSubgroupCheckAvailable () const
 
void EncodeElement (bool reversible, const Element &element, byte *encoded) const
 
unsigned int GetEncodedElementSize (bool reversible) const
 
Element DecodeElement (const byte *encoded, bool checkForGroupMembership) const
 
Integer ConvertElementToInteger (const Element &element) const
 
Integer GetMaxExponent () const
 
bool IsIdentity (const Element &element) const
 
void SimultaneousExponentiate (Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const
 
OID GetAlgorithmID () const
 
Element MultiplyElements (const Element &a, const Element &b) const
 
Element CascadeExponentiate (const Element &element1, const Integer &exponent1, const Element &element2, const Integer &exponent2) const
 
void BERDecode (BufferedTransformation &bt)
 
void DEREncode (BufferedTransformation &bt) const
 
void SetPointCompression (bool compress)
 
bool GetPointCompression () const
 
void SetEncodeAsOID (bool encodeAsOID)
 
bool GetEncodeAsOID () const
 
const EllipticCurve & GetCurve () const
 
bool operator== (const ThisClass &rhs) const
 
const DL_GroupPrecomputation
< Element > & 
GetGroupPrecomputation () const
 
bool Validate (RandomNumberGenerator &rng, unsigned int level) const
 check this object for errors More...
 
bool SupportsPrecomputation () const
 
void Precompute (unsigned int precomputationStorage=16)
 do precomputation More...
 
void LoadPrecomputation (BufferedTransformation &storedPrecomputation)
 retrieve previously saved precomputation
 
void SavePrecomputation (BufferedTransformation &storedPrecomputation) const
 save precomputation for later use
 
virtual const Element & GetSubgroupGenerator () const
 
virtual void SetSubgroupGenerator (const Element &base)
 
virtual Element ExponentiateBase (const Integer &exponent) const
 
virtual Element ExponentiateElement (const Element &base, const Integer &exponent) const
 
virtual Integer GetGroupOrder () const
 
virtual void EncodeElement (bool reversible, const Element &element, byte *encoded) const =0
 
virtual Integer ConvertElementToInteger (const Element &element) const =0
 
virtual bool ValidateElement (unsigned int level, const Element &element, const DL_FixedBasePrecomputation< Element > *precomp) const =0
 
virtual bool IsIdentity (const Element &element) const =0
 
virtual void SimultaneousExponentiate (Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const =0
 
void GenerateRandomWithKeySize (RandomNumberGenerator &rng, unsigned int keySize)
 calls the above function with a NameValuePairs object that just specifies "KeySize"
 
virtual void ThrowIfInvalid (RandomNumberGenerator &rng, unsigned int level) const
 throws InvalidMaterial if this object fails Validate() test
 
virtual void Save (BufferedTransformation &bt) const
 save key into a BufferedTransformation
 
virtual void Load (BufferedTransformation &bt)
 load key from a BufferedTransformation More...
 
void DoQuickSanityCheck () const
 
template<class T >
bool GetThisObject (T &object) const
 get a copy of this object or a subobject of it
 
template<class T >
bool GetThisPointer (T *&p) const
 get a pointer to this object, as a pointer to T
 
template<class T >
bool GetValue (const char *name, T &value) const
 get a named value, returns true if the name exists
 
template<class T >
GetValueWithDefault (const char *name, T defaultValue) const
 get a named value, returns the default if the name doesn't exist
 
std::string GetValueNames () const
 get a list of value names that can be retrieved
 
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
 
template<class T >
void GetRequiredParameter (const char *className, const char *name, T &value) const
 
void GetRequiredIntParameter (const char *className, const char *name, int &value) const
 

Static Public Member Functions

static std::string StaticAlgorithmNamePrefix ()
 
static OID GetNextRecommendedParametersOID (const OID &oid)
 
static void ThrowIfTypeMismatch (const char *name, const std::type_info &stored, const std::type_info &retrieving)
 used by derived classes to check for type mismatch
 

Protected Member Functions

unsigned int FieldElementLength () const
 
unsigned int ExponentLength () const
 
void ParametersChanged ()
 

Protected Attributes

OID m_oid
 
Integer m_n
 
bool m_compress
 
bool m_encodeAsOID
 
Integer m_k
 
EcPrecomputation< EC > m_groupPrecomputation
 
DL_FixedBasePrecomputationImpl
< typenameEcPrecomputation< EC >
::Element > 
m_gpc
 

Detailed Description

template<class EC>
class DL_GroupParameters_EC< EC >

Elliptic Curve Parameters.

This class corresponds to the ASN.1 sequence of the same name in ANSI X9.62 (also SEC 1).

Definition at line 25 of file eccrypto.h.

Member Function Documentation

template<class EC>
void DL_GroupParameters_EC< EC >::AssignFrom ( const NameValuePairs source)
virtual

assign values from source to this object

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

Implements CryptoMaterial.

template<class EC>
void DL_GroupParameters_EC< EC >::GenerateRandom ( RandomNumberGenerator rng,
const NameValuePairs alg 
)
virtual

this implementation doesn't actually generate a curve, it just initializes the parameters with existing values

parameters: (Curve, SubgroupGenerator, SubgroupOrder, Cofactor (optional)), or (GroupOID)

Reimplemented from GeneratableCryptoMaterial.

bool DL_GroupParameters< typenameEcPrecomputation< EC >::Element >::Validate ( RandomNumberGenerator rng,
unsigned int  level 
) const
inlinevirtualinherited

check this object for errors

Parameters
leveldenotes the level of thoroughness: 0 - using this object won't cause a crash or exception (rng is ignored) 1 - this object will probably function (encrypt, sign, etc.) correctly (but may not check for weak keys and such) 2 - make sure this object will function correctly, and do reasonable security checks 3 - do checks that may take a long time
Returns
true if the tests pass

Implements CryptoMaterial.

Definition at line 531 of file pubkey.h.

bool DL_GroupParameters< typenameEcPrecomputation< EC >::Element >::SupportsPrecomputation ( ) const
inlinevirtualinherited
Returns
whether this object supports precomputation

Reimplemented from CryptoMaterial.

Definition at line 555 of file pubkey.h.

void DL_GroupParameters< typenameEcPrecomputation< EC >::Element >::Precompute ( unsigned int  n = 16)
inlinevirtualinherited

do precomputation

The exact semantics of Precompute() is varies, but typically it means calculate a table of n objects that can be used later to speed up computation.

Reimplemented from CryptoMaterial.

Definition at line 557 of file pubkey.h.

virtual void CryptoMaterial::Load ( BufferedTransformation bt)
inlinevirtualinherited

load key from a BufferedTransformation

Exceptions
KeyingErrif decode fails
Note
Generally does not check that the key is valid. Call ValidateKey() or ThrowIfInvalidKey() to check that.

Reimplemented in InvertibleRSAFunction.

Definition at line 1071 of file cryptlib.h.

bool NameValuePairs::GetIntValue ( const char *  name,
int &  value 
) const
inlineinherited

get a named value with type int

used to ensure we don't accidentally try to get an unsigned int or some other type when we mean int (which is the most common case)

Definition at line 281 of file cryptlib.h.


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