sun.security.x509

Class Extension

java.lang.Object

sun.security.x509.Extension

Direct Known Subclasses:

AuthorityInfoAccessExtension, AuthorityKeyIdentifierExtension, BasicConstraintsExtension, CertificateIssuerExtension, CertificatePoliciesExtension, CRLDistributionPointsExtension, CRLNumberExtension, CRLReasonCodeExtension, ExtendedKeyUsageExtension, InhibitAnyPolicyExtension, IssuerAlternativeNameExtension, IssuingDistributionPointExtension, KeyUsageExtension, NameConstraintsExtension, NetscapeCertTypeExtension, PolicyConstraintsExtension, PolicyMappingsExtension, PrivateKeyUsageExtension, SubjectAlternativeNameExtension, SubjectKeyIdentifierExtension

public class Extension
extends java.lang.Object

Represent a X509 Extension Attribute.

Extensions are additional attributes which can be inserted in a X509 v3 certificate. For example a "Driving License Certificate" could have the driving license number as a extension.

Extensions are represented as a sequence of the extension identifier (Object Identifier), a boolean flag stating whether the extension is to be treated as being critical and the extension value itself (this is again a DER encoding of the extension value).

 ASN.1 definition of Extension:
 Extension ::= SEQUENCE {
      ExtensionId     OBJECT IDENTIFIER,
      critical        BOOLEAN DEFAULT FALSE,
      extensionValue  OCTET STRING
 }
 

All subclasses need to implement a constructor of the form

      (Boolean, Object)
 

where the Object is typically an array of DER encoded bytes.

Author:

Amit Kapoor, Hemma Prafullchandra

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	critical
protected ObjectIdentifier	extensionId
protected byte[]	extensionValue

Constructor Summary

Constructors

Constructor and Description
Extension() Default constructor.
Extension(DerValue derVal) Constructs an extension from a DER encoded array of bytes.
Extension(Extension ext) Constructs an Extension from another extension.
Extension(ObjectIdentifier extensionId, boolean critical, byte[] extensionValue) Constructs an Extension from individual components of ObjectIdentifier, criticality and the DER encoded OctetString.

Method Summary

Methods

Modifier and Type	Method and Description
void	encode(DerOutputStream out) Write the extension to the DerOutputStream.
boolean	equals(java.lang.Object other) Compares this Extension for equality with the specified object.
ObjectIdentifier	getExtensionId() Returns the ObjectIdentifier of the extension.
byte[]	getExtensionValue() Returns the extension value as an byte array for further processing.
int	hashCode() Returns a hashcode value for this Extension.
boolean	isCritical() Returns true if extension is critical.
java.lang.String	toString() Returns the Extension in user readable form.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

extensionId

protected ObjectIdentifier extensionId

critical

protected boolean critical

extensionValue

protected byte[] extensionValue

Constructor Detail

Extension

public Extension()

Default constructor. Used only by sub-classes.

Extension

public Extension(DerValue derVal)
          throws java.io.IOException

Constructs an extension from a DER encoded array of bytes.

Throws:

java.io.IOException

Extension

public Extension(ObjectIdentifier extensionId,
         boolean critical,
         byte[] extensionValue)
          throws java.io.IOException

Constructs an Extension from individual components of ObjectIdentifier, criticality and the DER encoded OctetString.

Parameters:

extensionId - the ObjectIdentifier of the extension

critical - the boolean indicating if the extension is critical

extensionValue - the DER encoded octet string of the value.

Throws:

java.io.IOException

Extension

public Extension(Extension ext)

Constructs an Extension from another extension. To be used for creating decoded subclasses.

Parameters:

ext - the extension to create from.

Method Detail

encode

public void encode(DerOutputStream out)
            throws java.io.IOException

Write the extension to the DerOutputStream.

Parameters:

out - the DerOutputStream to write the extension to.

Throws:

java.io.IOException - on encoding errors

isCritical

public boolean isCritical()

Returns true if extension is critical.

getExtensionId

public ObjectIdentifier getExtensionId()

Returns the ObjectIdentifier of the extension.

getExtensionValue

public byte[] getExtensionValue()

Returns the extension value as an byte array for further processing. Note, this is the raw DER value of the extension, not the DER encoded octet string which is in the certificate. This method does not return a clone; it is the responsibility of the caller to clone the array if necessary.

toString

public java.lang.String toString()

Returns the Extension in user readable form.

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Returns a hashcode value for this Extension.

Overrides:

hashCode in class java.lang.Object

Returns:

the hashcode value.

equals

public boolean equals(java.lang.Object other)

Compares this Extension for equality with the specified object. If the other object is an instanceof Extension, then its encoded form is retrieved and compared with the encoded form of this Extension.

Overrides:

equals in class java.lang.Object

Parameters:

other - the object to test for equality with this Extension.

Returns:

true iff the other object is of type Extension, and the criticality flag, object identifier and encoded extension value of the two Extensions match, false otherwise.