/*

 * Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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/*

 * ===========================================================================

 *

 * (C) Copyright IBM Corp. 2003 All Rights Reserved.

 *

 * ===========================================================================

 */

/*

 * $Id: XMLSignature.java,v 1.10 2005/05/10 16:03:48 mullan Exp $

 */

package javax.xml.crypto.dsig;

import javax.xml.crypto.KeySelector;

import javax.xml.crypto.KeySelectorResult;

import javax.xml.crypto.MarshalException;

import javax.xml.crypto.XMLStructure;

import javax.xml.crypto.dsig.keyinfo.KeyInfo;

import java.security.Signature;

import java.util.List;

/**

 * A representation of the XML <code>Signature</code> element as

 * defined in the <a href="http://www.w3.org/TR/xmldsig-core/">

 * W3C Recommendation for XML-Signature Syntax and Processing</a>.

 * This class contains methods for signing and validating XML signatures

 * with behavior as defined by the W3C specification. The XML Schema Definition

 * is defined as:

 * <pre><code>

 * <element name="Signature" type="ds:SignatureType"/>

 * <complexType name="SignatureType">

 *    <sequence>

 *      <element ref="ds:SignedInfo"/>

 *      <element ref="ds:SignatureValue"/>

 *      <element ref="ds:KeyInfo" minOccurs="0"/>

 *      <element ref="ds:Object" minOccurs="0" maxOccurs="unbounded"/>

 *    </sequence>

 *    <attribute name="Id" type="ID" use="optional"/>

 * </complexType>

 * </code></pre>

 * <p>

 * An <code>XMLSignature</code> instance may be created by invoking one of the

 * {@link XMLSignatureFactory#newXMLSignature newXMLSignature} methods of the

 * {@link XMLSignatureFactory} class.

 *

 * <p>If the contents of the underlying document containing the

 * <code>XMLSignature</code> are subsequently modified, the behavior is

 * undefined.

 *

 * <p>Note that this class is named <code>XMLSignature</code> rather than

 * <code>Signature</code> to avoid naming clashes with the existing

 * {@link Signature java.security.Signature} class.

 *

 * @see XMLSignatureFactory#newXMLSignature(SignedInfo, KeyInfo)

 * @see XMLSignatureFactory#newXMLSignature(SignedInfo, KeyInfo, List, String, String)

 * @author Joyce L. Leung

 * @author Sean Mullan

 * @author Erwin van der Koogh

 * @author JSR 105 Expert Group

 * @since 1.6

 */

public interface XMLSignature extends XMLStructure {

    /**

     * The XML Namespace URI of the W3C Recommendation for XML-Signature

     * Syntax and Processing.

     */

    final static String XMLNS = "http://www.w3.org/2000/09/xmldsig#";

    /**

     * Validates the signature according to the

     * <a href="http://www.w3.org/TR/xmldsig-core/#sec-CoreValidation">

     * core validation processing rules</a>. This method validates the

     * signature using the existing state, it does not unmarshal and

     * reinitialize the contents of the <code>XMLSignature</code> using the

     * location information specified in the context.

     *

     * <p>This method only validates the signature the first time it is

     * invoked. On subsequent invocations, it returns a cached result.

     *

     * @param validateContext the validating context

     * @return <code>true</code> if the signature passed core validation,

     *    otherwise <code>false</code>

     * @throws ClassCastException if the type of <code>validateContext</code>

     *    is not compatible with this <code>XMLSignature</code>

     * @throws NullPointerException if <code>validateContext</code> is

     *    <code>null</code>

     * @throws XMLSignatureException if an unexpected error occurs during

     *    validation that prevented the validation operation from completing

     */

    boolean validate(XMLValidateContext validateContext)

        throws XMLSignatureException;

    /**

     * Returns the key info of this <code>XMLSignature</code>.

     *

     * @return the key info (may be <code>null</code> if not specified)

     */

    KeyInfo getKeyInfo();

    /**

     * Returns the signed info of this <code>XMLSignature</code>.

     *

     * @return the signed info (never <code>null</code>)

     */

    SignedInfo getSignedInfo();

    /**

     * Returns an {@link java.util.Collections#unmodifiableList unmodifiable

     * list} of {@link XMLObject}s contained in this <code>XMLSignature</code>.

     *

     * @return an unmodifiable list of <code>XMLObject</code>s (may be empty

     *    but never <code>null</code>)

     */

    List<XMLObject> getObjects();

    /**

     * Returns the optional Id of this <code>XMLSignature</code>.

     *

     * @return the Id (may be <code>null</code> if not specified)

     */

    String getId();

    /**

     * Returns the signature value of this <code>XMLSignature</code>.

     *

     * @return the signature value

     */

    SignatureValue getSignatureValue();

    /**

     * Signs this <code>XMLSignature</code>.

     *

     * <p>If this method throws an exception, this <code>XMLSignature</code> and

     * the <code>signContext</code> parameter will be left in the state that

     * it was in prior to the invocation.

     *

     * @param signContext the signing context

     * @throws ClassCastException if the type of <code>signContext</code> is

     *    not compatible with this <code>XMLSignature</code>

     * @throws NullPointerException if <code>signContext</code> is

     *    <code>null</code>

     * @throws MarshalException if an exception occurs while marshalling

     * @throws XMLSignatureException if an unexpected exception occurs while

     *    generating the signature

     */

    void sign(XMLSignContext signContext) throws MarshalException,

        XMLSignatureException;

    /**

     * Returns the result of the {@link KeySelector}, if specified, after

     * this <code>XMLSignature</code> has been signed or validated.

     *

     * @return the key selector result, or <code>null</code> if a key

     *    selector has not been specified or this <code>XMLSignature</code>

     *    has not been signed or validated

     */

    KeySelectorResult getKeySelectorResult();

    /**

     * A representation of the XML <code>SignatureValue</code> element as

     * defined in the <a href="http://www.w3.org/TR/xmldsig-core/">

     * W3C Recommendation for XML-Signature Syntax and Processing</a>.

     * The XML Schema Definition is defined as:

     * <pre>

     *   <element name="SignatureValue" type="ds:SignatureValueType"/>

     *     <complexType name="SignatureValueType">

     *       <simpleContent>

     *         <extension base="base64Binary">

     *           <attribute name="Id" type="ID" use="optional"/>

     *         </extension>

     *       </simpleContent>

     *     </complexType>

     * </pre>

     *

     * @author Sean Mullan

     * @author JSR 105 Expert Group

     */

    public interface SignatureValue extends XMLStructure {

        /**

         * Returns the optional <code>Id</code> attribute of this

         * <code>SignatureValue</code>, which permits this element to be

         * referenced from elsewhere.

         *

         * @return the <code>Id</code> attribute (may be <code>null</code> if

         *    not specified)

         */

        String getId();

        /**

         * Returns the signature value of this <code>SignatureValue</code>.

         *

         * @return the signature value (may be <code>null</code> if the

         *    <code>XMLSignature</code> has not been signed yet). Each

         *    invocation of this method returns a new clone of the array to

         *    prevent subsequent modification.

         */

        byte[] getValue();

        /**

         * Validates the signature value. This method performs a

         * cryptographic validation of the signature calculated over the

         * <code>SignedInfo</code> of the <code>XMLSignature</code>.

         *

         * <p>This method only validates the signature the first

         * time it is invoked. On subsequent invocations, it returns a cached

         * result.

         *

         * @return <code>true</code> if the signature was

         *    validated successfully; <code>false</code> otherwise

         * @param validateContext the validating context

         * @throws NullPointerException if <code>validateContext</code> is

         *    <code>null</code>

         * @throws XMLSignatureException if an unexpected exception occurs while

         *    validating the signature

         */

        boolean validate(XMLValidateContext validateContext)

            throws XMLSignatureException;

    }

}