J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * reserved comment block |
| 3 | * DO NOT REMOVE OR ALTER! |
| 4 | */ |
| 5 | |
| 6 | /* |
| 7 | * Copyright 1999-2004 The Apache Software Foundation. |
| 8 | * |
| 9 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 10 | * you may not use this file except in compliance with the License. |
| 11 | * You may obtain a copy of the License at |
| 12 | * |
| 13 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 14 | * |
| 15 | * Unless required by applicable law or agreed to in writing, software |
| 16 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 17 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 18 | * See the License for the specific language governing permissions and |
| 19 | * limitations under the License. |
| 20 | * |
| 21 | */ |
| 22 | package com.sun.org.apache.xml.internal.security.transforms.implementations; |
| 23 | |
| 24 | |
| 25 | |
| 26 | import java.io.BufferedInputStream; |
| 27 | import java.io.IOException; |
| 28 | import java.io.OutputStream; |
| 29 | |
| 30 | import javax.xml.parsers.DocumentBuilderFactory; |
| 31 | import javax.xml.parsers.ParserConfigurationException; |
| 32 | |
| 33 | import com.sun.org.apache.xml.internal.security.c14n.CanonicalizationException; |
| 34 | import com.sun.org.apache.xml.internal.security.exceptions.Base64DecodingException; |
| 35 | import com.sun.org.apache.xml.internal.security.signature.XMLSignatureInput; |
| 36 | import com.sun.org.apache.xml.internal.security.transforms.TransformSpi; |
| 37 | import com.sun.org.apache.xml.internal.security.transforms.TransformationException; |
| 38 | import com.sun.org.apache.xml.internal.security.transforms.Transforms; |
| 39 | import com.sun.org.apache.xml.internal.security.utils.Base64; |
| 40 | import org.w3c.dom.Document; |
| 41 | import org.w3c.dom.Element; |
| 42 | import org.w3c.dom.Node; |
| 43 | import org.w3c.dom.Text; |
| 44 | import org.xml.sax.SAXException; |
| 45 | |
| 46 | |
| 47 | /** |
| 48 | * Implements the <CODE>http://www.w3.org/2000/09/xmldsig#base64</CODE> decoding |
| 49 | * transform. |
| 50 | * |
| 51 | * <p>The normative specification for base64 decoding transforms is |
| 52 | * <A HREF="http://www.w3.org/TR/2001/CR-xmldsig-core-20010419/#ref-MIME">[MIME]</A>. |
| 53 | * The base64 Transform element has no content. The input |
| 54 | * is decoded by the algorithms. This transform is useful if an |
| 55 | * application needs to sign the raw data associated with the encoded |
| 56 | * content of an element. </p> |
| 57 | * |
| 58 | * <p>This transform requires an octet stream for input. |
| 59 | * If an XPath node-set (or sufficiently functional alternative) is |
| 60 | * given as input, then it is converted to an octet stream by |
| 61 | * performing operations logically equivalent to 1) applying an XPath |
| 62 | * transform with expression self::text(), then 2) taking the string-value |
| 63 | * of the node-set. Thus, if an XML element is identified by a barename |
| 64 | * XPointer in the Reference URI, and its content consists solely of base64 |
| 65 | * encoded character data, then this transform automatically strips away the |
| 66 | * start and end tags of the identified element and any of its descendant |
| 67 | * elements as well as any descendant comments and processing instructions. |
| 68 | * The output of this transform is an octet stream.</p> |
| 69 | * |
| 70 | * @author Christian Geuer-Pollmann |
| 71 | * @see com.sun.org.apache.xml.internal.security.utils.Base64 |
| 72 | */ |
| 73 | public class TransformBase64Decode extends TransformSpi { |
| 74 | |
| 75 | /** Field implementedTransformURI */ |
| 76 | public static final String implementedTransformURI = |
| 77 | Transforms.TRANSFORM_BASE64_DECODE; |
| 78 | |
| 79 | /** |
| 80 | * Method engineGetURI |
| 81 | * |
| 82 | * @inheritDoc |
| 83 | */ |
| 84 | protected String engineGetURI() { |
| 85 | return TransformBase64Decode.implementedTransformURI; |
| 86 | } |
| 87 | |
| 88 | /** |
| 89 | * Method enginePerformTransform |
| 90 | * |
| 91 | * @param input |
| 92 | * @return {@link XMLSignatureInput} as the result of transformation |
| 93 | * @inheritDoc |
| 94 | * @throws CanonicalizationException |
| 95 | * @throws IOException |
| 96 | * @throws TransformationException |
| 97 | */ |
| 98 | protected XMLSignatureInput enginePerformTransform(XMLSignatureInput input) |
| 99 | throws IOException, CanonicalizationException, |
| 100 | TransformationException { |
| 101 | return enginePerformTransform(input,null); |
| 102 | } |
| 103 | protected XMLSignatureInput enginePerformTransform(XMLSignatureInput input, |
| 104 | OutputStream os) |
| 105 | throws IOException, CanonicalizationException, |
| 106 | TransformationException { |
| 107 | try { |
| 108 | if (input.isElement()) { |
| 109 | Node el=input.getSubNode(); |
| 110 | if (input.getSubNode().getNodeType()==Node.TEXT_NODE) { |
| 111 | el=el.getParentNode(); |
| 112 | } |
| 113 | StringBuffer sb=new StringBuffer(); |
| 114 | traverseElement((Element)el,sb); |
| 115 | if (os==null) { |
| 116 | byte[] decodedBytes = Base64.decode(sb.toString()); |
| 117 | return new XMLSignatureInput(decodedBytes); |
| 118 | } |
| 119 | Base64.decode(sb.toString().getBytes(),os); |
| 120 | XMLSignatureInput output=new XMLSignatureInput((byte[])null); |
| 121 | output.setOutputStream(os); |
| 122 | return output; |
| 123 | |
| 124 | } |
| 125 | if (input.isOctetStream() || input.isNodeSet()) { |
| 126 | |
| 127 | |
| 128 | if (os==null) { |
| 129 | byte[] base64Bytes = input.getBytes(); |
| 130 | byte[] decodedBytes = Base64.decode(base64Bytes); |
| 131 | return new XMLSignatureInput(decodedBytes); |
| 132 | } |
| 133 | if (input.isByteArray() || input.isNodeSet()) { |
| 134 | Base64.decode(input.getBytes(),os); |
| 135 | } else { |
| 136 | Base64.decode(new BufferedInputStream(input.getOctetStreamReal()) |
| 137 | ,os); |
| 138 | } |
| 139 | XMLSignatureInput output=new XMLSignatureInput((byte[])null); |
| 140 | output.setOutputStream(os); |
| 141 | return output; |
| 142 | |
| 143 | |
| 144 | } |
| 145 | |
| 146 | try { |
| 147 | //Exceptional case there is current not text case testing this(Before it was a |
| 148 | //a common case). |
| 149 | Document doc = |
| 150 | DocumentBuilderFactory.newInstance().newDocumentBuilder().parse( |
| 151 | input.getOctetStream()); |
| 152 | |
| 153 | Element rootNode = doc.getDocumentElement(); |
| 154 | StringBuffer sb = new StringBuffer(); |
| 155 | traverseElement(rootNode,sb); |
| 156 | byte[] decodedBytes = Base64.decode(sb.toString()); |
| 157 | |
| 158 | return new XMLSignatureInput(decodedBytes); |
| 159 | } catch (ParserConfigurationException e) { |
| 160 | throw new TransformationException("c14n.Canonicalizer.Exception",e); |
| 161 | } catch (SAXException e) { |
| 162 | throw new TransformationException("SAX exception", e); |
| 163 | } |
| 164 | } catch (Base64DecodingException e) { |
| 165 | throw new TransformationException("Base64Decoding", e); |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | void traverseElement(org.w3c.dom.Element node,StringBuffer sb) { |
| 170 | Node sibling=node.getFirstChild(); |
| 171 | while (sibling!=null) { |
| 172 | switch (sibling.getNodeType()) { |
| 173 | case Node.ELEMENT_NODE: |
| 174 | traverseElement((Element)sibling,sb); |
| 175 | break; |
| 176 | case Node.TEXT_NODE: |
| 177 | sb.append(((Text)sibling).getData()); |
| 178 | } |
| 179 | sibling=sibling.getNextSibling(); |
| 180 | } |
| 181 | } |
| 182 | } |