PK_SignatureScheme Class Reference

Interface for public-key signers and verifiers. More...

Inheritance diagram for PK_SignatureScheme:

Classes
class	InvalidKeyLength
	Exception throw when the private or public key has a length that can't be used. More...
class	KeyTooShort
	Exception throw when the private or public key is too short to sign or verify. More...

Public Member Functions
virtual size_t	SignatureLength () const =0
	Provides the signature length if it only depends on the key. More...
virtual size_t	MaxSignatureLength (size_t recoverablePartLength=0) const
	Provides the maximum signature length produced given the length of the recoverable message part. More...
virtual size_t	MaxRecoverableLength () const =0
	Provides the length of longest message that can be recovered. More...
virtual size_t	MaxRecoverableLengthFromSignatureLength (size_t signatureLength) const =0
	Provides the length of longest message that can be recovered from a signature of given length. More...
virtual bool	IsProbabilistic () const =0
	Determines whether a signature scheme requires a random number generator. More...
virtual bool	AllowNonrecoverablePart () const =0
	Determines whether the non-recoverable message part can be signed. More...
virtual bool	SignatureUpfront () const
	Determines whether the signature must be input before the message. More...
virtual bool	RecoverablePartFirst () const =0
	Determines whether the recoverable part must be input before the non-recoverable part. More...

Detailed Description

Interface for public-key signers and verifiers.

This class provides an interface common to signers and verifiers for querying scheme properties

See also

DL_SignatureSchemeBase, TF_SignatureSchemeBase, DL_SignerBase, TF_SignerBase

Definition at line 2767 of file cryptlib.h.

Member Function Documentation

SignatureLength()

virtual size_t PK_SignatureScheme::SignatureLength ( ) const

pure virtual

Provides the signature length if it only depends on the key.

Returns

the signature length if it only depends on the key, in bytes SignatureLength() returns the signature length if it only depends on the key, otherwise 0.

Implemented in ed25519Verifier, and ed25519Signer.

MaxSignatureLength()

virtual size_t PK_SignatureScheme::MaxSignatureLength ( size_t  recoverablePartLength = 0 ) const

inlinevirtual

Provides the maximum signature length produced given the length of the recoverable message part.

Parameters

recoverablePartLength

the length of the recoverable message part, in bytes

Returns

the maximum signature length produced for a given length of recoverable message part, in bytes MaxSignatureLength() returns the maximum signature length produced given the length of the recoverable message part.

Definition at line 2800 of file cryptlib.h.

MaxRecoverableLength()

virtual size_t PK_SignatureScheme::MaxRecoverableLength ( ) const

pure virtual

Provides the length of longest message that can be recovered.

Returns

the length of longest message that can be recovered, in bytes MaxRecoverableLength() returns the length of longest message that can be recovered, or 0 if this signature scheme does not support message recovery.

Implemented in ed25519Verifier, and ed25519Signer.

MaxRecoverableLengthFromSignatureLength()

virtual size_t PK_SignatureScheme::MaxRecoverableLengthFromSignatureLength ( size_t  signatureLength ) const

pure virtual

Provides the length of longest message that can be recovered from a signature of given length.

Parameters

signatureLength

the length of the signature, in bytes

Returns

the length of longest message that can be recovered from a signature of given length, in bytes MaxRecoverableLengthFromSignatureLength() returns the length of longest message that can be recovered from a signature of given length, or 0 if this signature scheme does not support message recovery.

Implemented in ed25519Verifier, ed25519Signer, DL_SignatureSchemeBase< PK_Signer, DL_PrivateKey< SCHEME_OPTIONS::Element > >, DL_SignatureSchemeBase< PK_Verifier, DL_PublicKey< SCHEME_OPTIONS::Element > >, DL_SignatureSchemeBase< PK_Verifier, DL_PublicKey< T > >, and DL_SignatureSchemeBase< PK_Signer, DL_PrivateKey< T > >.

IsProbabilistic()

virtual bool PK_SignatureScheme::IsProbabilistic ( ) const

pure virtual

Determines whether a signature scheme requires a random number generator.

Returns

true if the signature scheme requires a RandomNumberGenerator() to sign if IsProbabilistic() returns false, then NullRNG() can be passed to functions that take RandomNumberGenerator().

Implemented in ed25519Verifier, and ed25519Signer.

AllowNonrecoverablePart()

virtual bool PK_SignatureScheme::AllowNonrecoverablePart ( ) const

pure virtual

Determines whether the non-recoverable message part can be signed.

Returns

true if the non-recoverable message part can be signed

Implemented in ed25519Verifier, and ed25519Signer.

SignatureUpfront()

virtual bool PK_SignatureScheme::SignatureUpfront ( ) const

inlinevirtual

Determines whether the signature must be input before the message.

Returns

true if the signature must be input before the message during verifcation if SignatureUpfront() returns true, then you must input the signature before the message during verification. Otherwise you can input the signature at anytime.

Definition at line 2831 of file cryptlib.h.

RecoverablePartFirst()

virtual bool PK_SignatureScheme::RecoverablePartFirst ( ) const

pure virtual

Determines whether the recoverable part must be input before the non-recoverable part.

Returns

true if the recoverable part must be input before the non-recoverable part during signing RecoverablePartFirst() determines whether you must input the recoverable part before the non-recoverable part during signing

Implemented in ed25519Verifier, and ed25519Signer.

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

• cryptlib.h