ESIGN trapdoor function using the private key. More...

#include <esign.h>

Inheritance diagram for InvertibleESIGNFunction:

Public Member Functions
void	Initialize (const Integer &n, const Integer &e, const Integer &p, const Integer &q)
	Initialize a ESIGN private key with {n,e,p,q}. More...

void	Initialize (RandomNumberGenerator &rng, unsigned int modulusBits)
	Create a ESIGN private key. More...

void	Save (BufferedTransformation &bt) const
	Saves a key to a BufferedTransformation. More...

void	Load (BufferedTransformation &bt)
	Loads a key from a BufferedTransformation. More...

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

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

Integer	CalculateRandomizedInverse (RandomNumberGenerator &rng, const Integer &x) const
	Applies the inverse of the trapdoor function, using random data if required. More...

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...

void	AssignFrom (const NameValuePairs &source)
	Assign values to this object. More...

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

const Integer &	GetPrime1 () const

const Integer &	GetPrime2 () const

void	SetPrime1 (const Integer &p)

void	SetPrime2 (const Integer &q)

Public Member Functions inherited from ESIGNFunction
void	Initialize (const Integer &n, const Integer &e)
	Initialize a ESIGN public key with {n,e}. More...

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

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

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...

void	AssignFrom (const NameValuePairs &source)
	Assign values to this object. More...

Integer	ApplyFunction (const Integer &x) const
	Applies the trapdoor. More...

Integer	PreimageBound () const
	Returns the maximum size of a message before the trapdoor function is applied. More...

Integer	ImageBound () const
	Returns the maximum size of a representation after the trapdoor function is applied. More...

const Integer &	GetModulus () const

const Integer &	GetPublicExponent () const

void	SetModulus (const Integer &n)

void	SetPublicExponent (const Integer &e)

Public Member Functions inherited from TrapdoorFunction
Integer	ApplyRandomizedFunction (RandomNumberGenerator &rng, const Integer &x) const
	Applies the trapdoor function. More...

bool	IsRandomized () const
	Determines if the encryption algorithm is randomized. More...

virtual Integer	ApplyFunction (const Integer &x) const =0
	Applies the trapdoor. More...

virtual Integer	ApplyRandomizedFunction (RandomNumberGenerator &rng, const Integer &x) const =0
	Applies the trapdoor function, using random data if required. More...

virtual bool	IsRandomized () const
	Determines if the encryption algorithm is randomized. More...

Public Member Functions inherited from TrapdoorFunctionBounds
virtual Integer	PreimageBound () const =0
	Returns the maximum size of a message before the trapdoor function is applied. More...

virtual Integer	ImageBound () const =0
	Returns the maximum size of a representation after the trapdoor function is applied. More...

virtual Integer	MaxPreimage () const
	Returns the maximum size of a message before the trapdoor function is applied bound to a public key. More...

virtual Integer	MaxImage () const
	Returns the maximum size of a representation after the trapdoor function is applied bound to a public key. More...

Public Member Functions inherited from ASN1CryptoMaterial< PublicKey >
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 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 >
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...

Public Member Functions inherited from RandomizedTrapdoorFunctionInverse
virtual Integer	CalculateRandomizedInverse (RandomNumberGenerator &rng, const Integer &x) const =0
	Applies the inverse of the trapdoor function, using random data if required. More...

virtual bool	IsRandomized () const
	Determines if the decryption algorithm is randomized. 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...

Additional Inherited Members
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

ESIGN trapdoor function using the private key.

Since: Crypto++ 5.0

Definition at line 62 of file esign.h.

Member Function Documentation

◆ Initialize() [1/2]

void InvertibleESIGNFunction::Initialize	(	const Integer &	n,
		const Integer &	e,
		const Integer &	p,
		const Integer &	q
	)

inline

Initialize a ESIGN private key with {n,e,p,q}.

Parameters

n	modulus
e	public exponent
p	first prime factor
q	second prime factor

This Initialize() function overload initializes a private key from existing parameters.

Definition at line 74 of file esign.h.

◆ Initialize() [2/2]

void InvertibleESIGNFunction::Initialize	(	RandomNumberGenerator &	rng,
		unsigned int	modulusBits
	)

inline

Create a ESIGN private key.

Parameters

rng	a RandomNumberGenerator derived class
modulusBits	the size of the modulud, 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 83 of file esign.h.

◆ Save()

void InvertibleESIGNFunction::Save ( BufferedTransformation & bt ) const

inlinevirtual

Saves a key to a BufferedTransformation.

Parameters

bt	the destination BufferedTransformation

Exceptions

NotImplemented

Save() writes the material to a BufferedTransformation.

If the material is a key, then the key is written with ASN.1 DER encoding. The key includes an object identifier with an algorithm id, like a subjectPublicKeyInfo.

A "raw" key without the "key info" can be saved using a key's DEREncode() method.

If a derived class does not override Save(), then the base class throws NotImplemented().

Reimplemented from CryptoMaterial.

Definition at line 87 of file esign.h.

◆ Load()

void InvertibleESIGNFunction::Load ( BufferedTransformation & bt )

inlinevirtual

Loads a key from a BufferedTransformation.

Parameters

bt	the source BufferedTransformation

Exceptions

KeyingErr

Load() attempts to read material from a BufferedTransformation. If the material is a key that was generated outside the library, then the following usually applies:

the key should be ASN.1 BER encoded
the key should be a "key info"

"key info" means the key should have an object identifier with an algorithm id, like a subjectPublicKeyInfo.

To read a "raw" key without the "key info", then call the key's BERDecode() method.

Note: Load() generally does not check that the key is valid. Call Validate(), if needed.

Reimplemented from CryptoMaterial.

Definition at line 91 of file esign.h.

◆ BERDecode()

void InvertibleESIGNFunction::BERDecode ( BufferedTransformation & bt )

virtual

Decode this object from a BufferedTransformation.

Parameters

bt	BufferedTransformation object

Uses Basic Encoding Rules (BER)

Reimplemented from ESIGNFunction.

Definition at line 133 of file esign.cpp.

◆ DEREncode()

void InvertibleESIGNFunction::DEREncode ( BufferedTransformation & bt ) const

virtual

Encode this object into a BufferedTransformation.

Parameters

bt	BufferedTransformation object

Uses Distinguished Encoding Rules (DER)

Reimplemented from ESIGNFunction.

Definition at line 143 of file esign.cpp.

◆ CalculateRandomizedInverse()

Integer InvertibleESIGNFunction::CalculateRandomizedInverse	(	RandomNumberGenerator &	rng,
		const Integer &	x
	)		const

virtual

Applies the inverse of the trapdoor function, using random data if required.

Parameters

rng	a RandomNumberGenerator derived class
x	the message on which the decryption function is applied

Returns: the message x decrypted under the private key

CalculateRandomizedInverse is a generalization of decryption using the private key The RandomNumberGenerator may (or may not) be required. Derived classes must implement it.

Implements RandomizedTrapdoorFunctionInverse.

Definition at line 153 of file esign.cpp.

◆ Validate()

bool InvertibleESIGNFunction::Validate	(	RandomNumberGenerator &	rng,
		unsigned int	level
	)		const

virtual

Check this object for errors.

Parameters

rng	a RandomNumberGenerator for objects which use randomized testing
level	the 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.

See also: ThrowIfInvalid()

Reimplemented from ESIGNFunction.

Definition at line 194 of file esign.cpp.

◆ GetVoidValue()

bool InvertibleESIGNFunction::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 ESIGNFunction.

Definition at line 217 of file esign.cpp.

◆ AssignFrom()

void InvertibleESIGNFunction::AssignFrom ( const NameValuePairs & source )

virtual

Assign values to this object.

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

Reimplemented from ESIGNFunction.

Definition at line 225 of file esign.cpp.

◆ GenerateRandom()

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

virtual

parameters: (ModulusSize)

Reimplemented from GeneratableCryptoMaterial.

Definition at line 88 of file esign.cpp.

◆ GetPrime1()

const Integer & InvertibleESIGNFunction::GetPrime1 ( ) const

inline

Definition at line 106 of file esign.h.

◆ GetPrime2()

const Integer & InvertibleESIGNFunction::GetPrime2 ( ) const

inline

Definition at line 107 of file esign.h.

◆ SetPrime1()

void InvertibleESIGNFunction::SetPrime1 ( const Integer & p )

inline

Definition at line 109 of file esign.h.

◆ SetPrime2()

void InvertibleESIGNFunction::SetPrime2 ( const Integer & q )

inline

Definition at line 110 of file esign.h.

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

Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ Initialize() [1/2]

◆ Initialize() [2/2]

◆ Save()

◆ Load()

◆ BERDecode()

◆ DEREncode()

◆ CalculateRandomizedInverse()

◆ Validate()

◆ GetVoidValue()

◆ AssignFrom()

◆ GenerateRandom()

◆ GetPrime1()

◆ GetPrime2()

◆ SetPrime1()

◆ SetPrime2()