PK_Decryptor Class Reference

#include <cryptlib.h>

Inheritance diagram for PK_Decryptor:

List of all members.

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Detailed Description

interface for public-key decryptors

Definition at line 1187 of file cryptlib.h.

Public Member Functions
virtual DecodingResult	Decrypt (RandomNumberGenerator &rng, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs &parameters=g_nullNameValuePairs) const =0
	decrypt a byte string, and return the length of plaintext
virtual BufferedTransformation *	CreateDecryptionFilter (RandomNumberGenerator &rng, BufferedTransformation *attachment=NULL, const NameValuePairs &parameters=g_nullNameValuePairs) const
	create a new decryption filter
DecodingResult	FixedLengthDecrypt (RandomNumberGenerator &rng, const byte *ciphertext, byte *plaintext, const NameValuePairs &parameters=g_nullNameValuePairs) const
	decrypt a fixed size ciphertext
virtual size_t	MaxPlaintextLength (size_t ciphertextLength) const =0
	maximum length of plaintext for a given ciphertext length
virtual size_t	CiphertextLength (size_t plaintextLength) const =0
	calculate length of ciphertext given length of plaintext
virtual bool	ParameterSupported (const char *name) const =0
	this object supports the use of the parameter with the given name
virtual size_t	FixedCiphertextLength () const
	return fixed ciphertext length, if one exists, otherwise return 0
virtual size_t	FixedMaxPlaintextLength () const
	return maximum plaintext length given the fixed ciphertext length, if one exists, otherwise return 0
CryptoMaterial &	AccessMaterial ()
	returns a reference to the crypto material used by this object
const CryptoMaterial &	GetMaterial () const
	returns a const reference to the crypto material used by this object
virtual PrivateKey &	AccessPrivateKey ()=0
virtual const PrivateKey &	GetPrivateKey () const
void	BERDecode (BufferedTransformation &bt)
	for backwards compatibility, calls AccessMaterial().Load(bt)
void	DEREncode (BufferedTransformation &bt) const
	for backwards compatibility, calls GetMaterial().Save(bt)
virtual std::string	AlgorithmName () const
	returns name of this algorithm, not universally implemented yet
virtual Clonable *	Clone () const
	this is not implemented by most classes yet

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Member Function Documentation

virtual DecodingResult PK_Decryptor::Decrypt	(	RandomNumberGenerator &	rng,
		const byte *	ciphertext,
		size_t	ciphertextLength,
		byte *	plaintext,
		const NameValuePairs &	parameters = g_nullNameValuePairs
	)			const [pure virtual]

decrypt a byte string, and return the length of plaintext

Precondition:

size of plaintext == MaxPlaintextLength(ciphertextLength) bytes.

Returns:

the actual length of the plaintext, indication that decryption failed.

Implemented in TF_DecryptorBase, DL_DecryptorBase< T >, and DL_DecryptorBase< SCHEME_OPTIONS::Element >.

Referenced by PK_DefaultDecryptionFilter::Put2().

BufferedTransformation * PK_Decryptor::CreateDecryptionFilter	(	RandomNumberGenerator &	rng,
		BufferedTransformation *	attachment = NULL,
		const NameValuePairs &	parameters = g_nullNameValuePairs
	)			const [virtual]

create a new decryption filter

Note:

caller is responsible for deleting the returned pointer

Definition at line 618 of file cryptlib.cpp.

virtual size_t PK_CryptoSystem::MaxPlaintextLength

(

size_t

ciphertextLength

)

const [pure virtual, inherited]

maximum length of plaintext for a given ciphertext length

Note:

This function returns 0 if ciphertextLength is not valid (too long or too short).

Implemented in PK_FixedLengthCryptoSystemImpl< PK_Encryptor >, PK_FixedLengthCryptoSystemImpl< PK_Decryptor >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< SCHEME_OPTIONS::Element > >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< T > >, DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< SCHEME_OPTIONS::Element > >, and DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< T > >.

Referenced by PK_DefaultDecryptionFilter::Put2().

virtual size_t PK_CryptoSystem::CiphertextLength

(

size_t

plaintextLength

)

const [pure virtual, inherited]

calculate length of ciphertext given length of plaintext

Note:

This function returns 0 if plaintextLength is not valid (too long).

Implemented in PK_FixedLengthCryptoSystemImpl< PK_Encryptor >, PK_FixedLengthCryptoSystemImpl< PK_Decryptor >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< SCHEME_OPTIONS::Element > >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< T > >, DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< SCHEME_OPTIONS::Element > >, and DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< T > >.

Referenced by PK_DefaultEncryptionFilter::Put2().

virtual bool PK_CryptoSystem::ParameterSupported

(

const char *

name

)

const [pure virtual, inherited]

this object supports the use of the parameter with the given name

some possible parameter names: EncodingParameters, KeyDerivationParameters

Implemented in TF_CryptoSystemBase< PK_Decryptor, TF_Base< TrapdoorFunctionInverse, PK_EncryptionMessageEncodingMethod > >, TF_CryptoSystemBase< PK_Encryptor, TF_Base< RandomizedTrapdoorFunction, PK_EncryptionMessageEncodingMethod > >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< SCHEME_OPTIONS::Element > >, DL_CryptoSystemBase< PK_Decryptor, DL_PrivateKey< T > >, DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< SCHEME_OPTIONS::Element > >, and DL_CryptoSystemBase< PK_Encryptor, DL_PublicKey< T > >.

virtual size_t PK_CryptoSystem::FixedCiphertextLength

(

)

const [inline, virtual, inherited]

return fixed ciphertext length, if one exists, otherwise return 0

Note:

"Fixed" here means length of ciphertext does not depend on length of plaintext. It usually does depend on the key length.

Reimplemented in TF_CryptoSystemBase< PK_Decryptor, TF_Base< TrapdoorFunctionInverse, PK_EncryptionMessageEncodingMethod > >, and TF_CryptoSystemBase< PK_Encryptor, TF_Base< RandomizedTrapdoorFunction, PK_EncryptionMessageEncodingMethod > >.

Definition at line 1147 of file cryptlib.h.

Referenced by FixedLengthDecrypt().

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

• cryptlib.h
• cryptlib.cpp

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