org.apache.xml.security.transforms.implementations.TransformBase64Decode Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.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.Transform;
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.apache.xml.security.utils.XMLUtils;
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 http://www.w3.org/2000/09/xmldsig#base64 decoding
* transform.
*
* The normative specification for base64 decoding transforms is
* [MIME].
* 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.
*
* 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.
*
* @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, Transform transformObject
) throws IOException, CanonicalizationException, TransformationException {
return enginePerformTransform(input, null, transformObject);
}
protected XMLSignatureInput enginePerformTransform(
XMLSignatureInput input, OutputStream os, Transform transformObject
) throws IOException, CanonicalizationException, TransformationException {
try {
if (input.isElement()) {
Node el = input.getSubNode();
if (input.getSubNode().getNodeType() == Node.TEXT_NODE) {
el = el.getParentNode();
}
StringBuilder sb = new StringBuilder();
traverseElement((Element)el, sb);
if (os == null) {
byte[] decodedBytes = Base64.decode(sb.toString());
XMLSignatureInput output = new XMLSignatureInput(decodedBytes);
output.setSecureValidation(secureValidation);
return output;
}
Base64.decode(sb.toString(), os);
XMLSignatureInput output = new XMLSignatureInput((byte[])null);
output.setSecureValidation(secureValidation);
output.setOutputStream(os);
return output;
}
if (input.isOctetStream() || input.isNodeSet()) {
if (os == null) {
byte[] base64Bytes = input.getBytes();
byte[] decodedBytes = Base64.decode(base64Bytes);
XMLSignatureInput output = new XMLSignatureInput(decodedBytes);
output.setSecureValidation(secureValidation);
return output;
}
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.setSecureValidation(secureValidation);
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 =
XMLUtils.createDocumentBuilder(false, secureValidation).parse(input.getOctetStream());
Element rootNode = doc.getDocumentElement();
StringBuilder sb = new StringBuilder();
traverseElement(rootNode, sb);
byte[] decodedBytes = Base64.decode(sb.toString());
XMLSignatureInput output = new XMLSignatureInput(decodedBytes);
output.setSecureValidation(secureValidation);
return output;
} catch (ParserConfigurationException e) {
throw new TransformationException(e, "c14n.Canonicalizer.Exception");
} catch (SAXException e) {
throw new TransformationException(e, "SAX exception");
}
} catch (Base64DecodingException e) {
throw new TransformationException(e, "Base64Decoding");
}
}
void traverseElement(Element node, StringBuilder 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();
}
}
}