com.itextpdf.signatures

Class PrivateKeySignature

java.lang.Object

com.itextpdf.signatures.PrivateKeySignature

All Implemented Interfaces:

IExternalSignature

public class PrivateKeySignature
extends Object
implements IExternalSignature

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

Author:

Paulo Soares

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
String	getDigestAlgorithmName() Returns the digest algorithm.
String	getSignatureAlgorithmName() Returns the signature algorithm used for signing, disregarding the digest function.
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

Constructor Detail

PrivateKeySignature

public PrivateKeySignature(PrivateKey pk,
                           String hashAlgorithm,
                           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(PrivateKey pk,
                           String hashAlgorithm,
                           String signatureAlgorithm,
                           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 String getDigestAlgorithmName()

Returns the digest algorithm.

Specified by:

getDigestAlgorithmName in interface IExternalSignature

Returns:

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

getSignatureAlgorithmName

public 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 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:

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