| |
| /* |
| * Copyright 1999-2004 The Apache Software Foundation. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| package org.apache.xml.security.transforms.implementations; |
| |
| |
| |
| import java.io.BufferedInputStream; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| import javax.xml.parsers.DocumentBuilderFactory; |
| import javax.xml.parsers.ParserConfigurationException; |
| |
| import org.apache.xml.security.c14n.CanonicalizationException; |
| import org.apache.xml.security.exceptions.Base64DecodingException; |
| import org.apache.xml.security.signature.XMLSignatureInput; |
| import org.apache.xml.security.transforms.TransformSpi; |
| import org.apache.xml.security.transforms.TransformationException; |
| import org.apache.xml.security.transforms.Transforms; |
| import org.apache.xml.security.utils.Base64; |
| import org.w3c.dom.Document; |
| import org.w3c.dom.Element; |
| import org.w3c.dom.Node; |
| import org.w3c.dom.Text; |
| import org.xml.sax.SAXException; |
| |
| |
| /** |
| * Implements the <CODE>http://www.w3.org/2000/09/xmldsig#base64</CODE> decoding |
| * transform. |
| * |
| * <p>The normative specification for base64 decoding transforms is |
| * <A HREF="http://www.w3.org/TR/2001/CR-xmldsig-core-20010419/#ref-MIME">[MIME]</A>. |
| * The base64 Transform element has no content. The input |
| * is decoded by the algorithms. This transform is useful if an |
| * application needs to sign the raw data associated with the encoded |
| * content of an element. </p> |
| * |
| * <p>This transform requires an octet stream for input. |
| * If an XPath node-set (or sufficiently functional alternative) is |
| * given as input, then it is converted to an octet stream by |
| * performing operations logically equivalent to 1) applying an XPath |
| * transform with expression self::text(), then 2) taking the string-value |
| * of the node-set. Thus, if an XML element is identified by a barename |
| * XPointer in the Reference URI, and its content consists solely of base64 |
| * encoded character data, then this transform automatically strips away the |
| * start and end tags of the identified element and any of its descendant |
| * elements as well as any descendant comments and processing instructions. |
| * The output of this transform is an octet stream.</p> |
| * |
| * @author Christian Geuer-Pollmann |
| * @see org.apache.xml.security.utils.Base64 |
| */ |
| public class TransformBase64Decode extends TransformSpi { |
| |
| /** Field implementedTransformURI */ |
| public static final String implementedTransformURI = |
| Transforms.TRANSFORM_BASE64_DECODE; |
| |
| /** |
| * Method engineGetURI |
| * |
| * @inheritDoc |
| */ |
| protected String engineGetURI() { |
| return TransformBase64Decode.implementedTransformURI; |
| } |
| |
| /** |
| * Method enginePerformTransform |
| * |
| * @param input |
| * @return {@link XMLSignatureInput} as the result of transformation |
| * @inheritDoc |
| * @throws CanonicalizationException |
| * @throws IOException |
| * @throws TransformationException |
| */ |
| protected XMLSignatureInput enginePerformTransform(XMLSignatureInput input) |
| throws IOException, CanonicalizationException, |
| TransformationException { |
| return enginePerformTransform(input,null); |
| } |
| protected XMLSignatureInput enginePerformTransform(XMLSignatureInput input, |
| OutputStream os) |
| throws IOException, CanonicalizationException, |
| TransformationException { |
| try { |
| if (input.isElement()) { |
| Node el=input.getSubNode(); |
| if (input.getSubNode().getNodeType()==Node.TEXT_NODE) { |
| el=el.getParentNode(); |
| } |
| StringBuffer sb=new StringBuffer(); |
| traverseElement((Element)el,sb); |
| if (os==null) { |
| byte[] decodedBytes = Base64.decode(sb.toString()); |
| return new XMLSignatureInput(decodedBytes); |
| } |
| Base64.decode(sb.toString().getBytes(),os); |
| XMLSignatureInput output=new XMLSignatureInput((byte[])null); |
| output.setOutputStream(os); |
| return output; |
| |
| } |
| if (input.isOctetStream() || input.isNodeSet()) { |
| |
| |
| if (os==null) { |
| byte[] base64Bytes = input.getBytes(); |
| byte[] decodedBytes = Base64.decode(base64Bytes); |
| return new XMLSignatureInput(decodedBytes); |
| } |
| if (input.isByteArray() || input.isNodeSet()) { |
| Base64.decode(input.getBytes(),os); |
| } else { |
| Base64.decode(new BufferedInputStream(input.getOctetStreamReal()) |
| ,os); |
| } |
| XMLSignatureInput output=new XMLSignatureInput((byte[])null); |
| output.setOutputStream(os); |
| return output; |
| |
| |
| } |
| |
| try { |
| //Exceptional case there is current not text case testing this(Before it was a |
| //a common case). |
| Document doc = |
| DocumentBuilderFactory.newInstance().newDocumentBuilder().parse( |
| input.getOctetStream()); |
| |
| Element rootNode = doc.getDocumentElement(); |
| StringBuffer sb = new StringBuffer(); |
| traverseElement(rootNode,sb); |
| byte[] decodedBytes = Base64.decode(sb.toString()); |
| |
| return new XMLSignatureInput(decodedBytes); |
| } catch (ParserConfigurationException e) { |
| throw new TransformationException("c14n.Canonicalizer.Exception",e); |
| } catch (SAXException e) { |
| throw new TransformationException("SAX exception", e); |
| } |
| } catch (Base64DecodingException e) { |
| throw new TransformationException("Base64Decoding", e); |
| } |
| } |
| |
| void traverseElement(org.w3c.dom.Element node,StringBuffer sb) { |
| Node sibling=node.getFirstChild(); |
| while (sibling!=null) { |
| switch (sibling.getNodeType()) { |
| case Node.ELEMENT_NODE: |
| traverseElement((Element)sibling,sb); |
| break; |
| case Node.TEXT_NODE: |
| sb.append(((Text)sibling).getData()); |
| } |
| sibling=sibling.getNextSibling(); |
| } |
| } |
| } |