Package com.itextpdf.signatures

Class PrivateKeySignature

java.lang.Object

com.itextpdf.signatures.PrivateKeySignature

All Implemented Interfaces:

IExternalSignature

public class PrivateKeySignature
extends java.lang.Object
implements IExternalSignature

Implementation of the IExternalSignature interface that can be used when you have a PrivateKey object.

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.String	hashAlgorithm	The hash algorithm.
private IApplicableSignatureParams	parameters	The algorithm parameters.
private java.security.PrivateKey	pk	The private key object.
private java.lang.String	provider	The security provider
private java.lang.String	signatureAlgorithm	The encryption algorithm (obtained from the private key)

Constructor Summary

Constructors

Constructor	Description
PrivateKeySignature(java.security.PrivateKey pk, java.lang.String hashAlgorithm, java.lang.String provider)	Creates a PrivateKeySignature instance.
PrivateKeySignature(java.security.PrivateKey pk, java.lang.String hashAlgorithm, java.lang.String signatureAlgorithm, java.lang.String provider, IApplicableSignatureParams params)	Creates a PrivateKeySignature instance.

Method Summary

Modifier and Type	Method	Description
java.lang.String	getDigestAlgorithmName()	Returns the digest algorithm.
java.lang.String	getSignatureAlgorithmName()	Returns the signature algorithm used for signing, disregarding the digest function.
private java.lang.String	getSignatureMechanismName()
ISignatureMechanismParams	getSignatureMechanismParameters()	Return the algorithm parameters that need to be encoded together with the signature mechanism identifier.
byte[]	sign(byte[] message)	Signs the given message using the encryption algorithm in combination with the hash algorithm.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

pk

private final java.security.PrivateKey pk

The private key object.

hashAlgorithm

private final java.lang.String hashAlgorithm

The hash algorithm.

signatureAlgorithm

private final java.lang.String signatureAlgorithm

The encryption algorithm (obtained from the private key)

provider

private final java.lang.String provider

The security provider

parameters

private final IApplicableSignatureParams parameters

The algorithm parameters.

Constructor Detail

PrivateKeySignature

public PrivateKeySignature(java.security.PrivateKey pk,
                           java.lang.String hashAlgorithm,
                           java.lang.String provider)

Creates a PrivateKeySignature instance.

Parameters:

pk - A PrivateKey object.

hashAlgorithm - A hash algorithm (e.g. "SHA-1", "SHA-256",...).

provider - A security provider (e.g. "BC").

PrivateKeySignature

public PrivateKeySignature(java.security.PrivateKey pk,
                           java.lang.String hashAlgorithm,
                           java.lang.String signatureAlgorithm,
                           java.lang.String provider,
                           IApplicableSignatureParams params)

Creates a PrivateKeySignature instance.

Parameters:

pk - A PrivateKey object.

hashAlgorithm - A hash algorithm (e.g. "SHA-1", "SHA-256",...).

signatureAlgorithm - A signiture algorithm (e.g. "RSASSA-PSS", "id-signedData", "sha256WithRSAEncryption", ...)

provider - A security provider (e.g. "BC").

params - Parameters for using RSASSA-PSS or other algorithms requiring them.

Method Detail

getDigestAlgorithmName

public java.lang.String getDigestAlgorithmName()

Returns the digest algorithm.

Specified by:

getDigestAlgorithmName in interface IExternalSignature

Returns:

The digest algorithm (e.g. "SHA-1", "SHA-256,...").

getSignatureAlgorithmName

public java.lang.String getSignatureAlgorithmName()

Returns the signature algorithm used for signing, disregarding the digest function.

Specified by:

getSignatureAlgorithmName in interface IExternalSignature

Returns:

The signature algorithm ("RSA", "DSA", "ECDSA", "Ed25519" or "Ed448").

getSignatureMechanismParameters

public ISignatureMechanismParams getSignatureMechanismParameters()

Return the algorithm parameters that need to be encoded together with the signature mechanism identifier. If there are no parameters, return `null`. A non-null value is required for RSASSA-PSS; see RSASSAPSSMechanismParams.

Specified by:

getSignatureMechanismParameters in interface IExternalSignature

Returns:

algorithm parameters

sign

public byte[] sign(byte[] message)
            throws java.security.GeneralSecurityException

Signs the given message using the encryption algorithm in combination with the hash algorithm.

Specified by:

sign in interface IExternalSignature

Parameters:

message - The message you want to be hashed and signed.

Returns:

A signed message digest.

Throws:

java.security.GeneralSecurityException - when requested cryptographic algorithm or security provider is not available

getSignatureMechanismName

private java.lang.String getSignatureMechanismName()