src/ooxml/java/org/apache/poi/poifs/crypt/dsig/SignaturePart.java - poi - Git at Google

 /* ====================================================================
    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.poi.poifs.crypt.dsig;

 import static org.apache.poi.ooxml.POIXMLTypeLoader.DEFAULT_XML_OPTIONS;
 import static org.apache.poi.poifs.crypt.dsig.facets.SignatureFacet.MS_DIGSIG_NS;
 import static org.apache.poi.poifs.crypt.dsig.facets.SignatureFacet.XML_DIGSIG_NS;

 import java.io.IOException;
 import java.security.cert.X509Certificate;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.function.Consumer;

 import javax.xml.crypto.MarshalException;
 import javax.xml.crypto.URIDereferencer;
 import javax.xml.crypto.dsig.XMLSignature;
 import javax.xml.crypto.dsig.XMLSignatureException;
 import javax.xml.crypto.dsig.XMLSignatureFactory;
 import javax.xml.crypto.dsig.dom.DOMValidateContext;
 import javax.xml.namespace.NamespaceContext;
 import javax.xml.xpath.XPath;
 import javax.xml.xpath.XPathConstants;
 import javax.xml.xpath.XPathExpressionException;

 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.poi.EncryptedDocumentException;
 import org.apache.poi.ooxml.util.DocumentHelper;
 import org.apache.poi.ooxml.util.XPathHelper;
 import org.apache.poi.openxml4j.opc.PackagePart;
 import org.apache.xmlbeans.XmlException;
 import org.w3.x2000.x09.xmldsig.SignatureDocument;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.NodeList;
 import org.xml.sax.SAXException;

 public class SignaturePart {
     private static final Logger LOG = LogManager.getLogger(SignaturePart.class);
     private static final String XMLSEC_VALIDATE_MANIFEST = "org.jcp.xml.dsig.validateManifests";


     private final PackagePart signaturePart;
     private final SignatureInfo signatureInfo;
     private X509Certificate signer;
     private List<X509Certificate> certChain;

     /* package */ SignaturePart(final PackagePart signaturePart, final SignatureInfo signatureInfo) {
         this.signaturePart = signaturePart;
         this.signatureInfo = signatureInfo;
     }

     /**
      * @return the package part containing the signature
      */
     public PackagePart getPackagePart() {
         return signaturePart;
     }

     /**
      * @return the signer certificate
      */
     public X509Certificate getSigner() {
         return signer;
     }

     /**
      * @return the certificate chain of the signer
      */
     public List<X509Certificate> getCertChain() {
         return certChain;
     }

     /**
      * Helper method for examining the xml signature
      *
      * @return the xml signature document
      * @throws IOException if the xml signature doesn't exist or can't be read
      * @throws XmlException if the xml signature is malformed
      */
     public SignatureDocument getSignatureDocument() throws IOException, XmlException {
         // TODO: check for XXE
         return SignatureDocument.Factory.parse(signaturePart.getInputStream(), DEFAULT_XML_OPTIONS);
     }

     /**
      * @return true, when the xml signature is valid, false otherwise
      *
      * @throws EncryptedDocumentException if the signature can't be extracted or if its malformed
      */
     public boolean validate() {
         KeyInfoKeySelector keySelector = new KeyInfoKeySelector();
         XPath xpath = XPathHelper.getFactory().newXPath();
         xpath.setNamespaceContext(new XPathNSContext());

         try {
             Document doc = DocumentHelper.readDocument(signaturePart.getInputStream());
             NodeList nl = (NodeList)xpath.compile("//*[@Id]").evaluate(doc, XPathConstants.NODESET);
             final int length = nl.getLength();
             for (int i=0; i<length; i++) {
                 ((Element)nl.item(i)).setIdAttribute("Id", true);
             }

             DOMValidateContext domValidateContext = new DOMValidateContext(keySelector, doc);
             domValidateContext.setProperty(XMLSEC_VALIDATE_MANIFEST, Boolean.TRUE);

             URIDereferencer uriDereferencer = signatureInfo.getUriDereferencer();
             domValidateContext.setURIDereferencer(uriDereferencer);

             XMLSignatureFactory xmlSignatureFactory = signatureInfo.getSignatureFactory();
             XMLSignature xmlSignature = xmlSignatureFactory.unmarshalXMLSignature(domValidateContext);

             boolean valid = xmlSignature.validate(domValidateContext);

             if (valid) {
                 signer = keySelector.getSigner();
                 certChain = keySelector.getCertChain();
                 extractConfig(doc, xmlSignature);
             }

             return valid;
         } catch (IOException e) {
             String s = "error in reading document";
             LOG.atError().withThrowable(e).log(s);
             throw new EncryptedDocumentException(s, e);
         } catch (SAXException e) {
             String s = "error in parsing document";
             LOG.atError().withThrowable(e).log(s);
             throw new EncryptedDocumentException(s, e);
         } catch (XPathExpressionException e) {
             String s = "error in searching document with xpath expression";
             LOG.atError().withThrowable(e).log(s);
             throw new EncryptedDocumentException(s, e);
         } catch (MarshalException e) {
             String s = "error in unmarshalling the signature";
             LOG.atError().withThrowable(e).log(s);
             throw new EncryptedDocumentException(s, e);
         } catch (XMLSignatureException e) {
             String s = "error in validating the signature";
             LOG.atError().withThrowable(e).log(s);
             throw new EncryptedDocumentException(s, e);
         }
     }

     private void extractConfig(final Document doc, final XMLSignature xmlSignature) throws XPathExpressionException {
         SignatureConfig signatureConfig = signatureInfo.getSignatureConfig();
         if (!signatureConfig.isUpdateConfigOnValidate()) {
             return;
         }

         signatureConfig.setSigningCertificateChain(certChain);
         signatureConfig.setSignatureMethodFromUri(xmlSignature.getSignedInfo().getSignatureMethod().getAlgorithm());

         final XPath xpath = XPathHelper.getFactory().newXPath();
         xpath.setNamespaceContext(new XPathNSContext());

         final Map<String,Consumer<String>> m = new HashMap<>();
         m.put("//mdssi:SignatureTime/mdssi:Value", signatureConfig::setExecutionTime);
         m.put("//xd:ClaimedRole", signatureConfig::setXadesRole);
         m.put("//dsss:SignatureComments", signatureConfig::setSignatureDescription);
         m.put("//xd:QualifyingProperties//xd:SignedSignatureProperties//ds:DigestMethod/@Algorithm", signatureConfig::setXadesDigestAlgo);
         m.put("//ds:CanonicalizationMethod", signatureConfig::setCanonicalizationMethod);

         for (Map.Entry<String,Consumer<String>> me : m.entrySet()) {
             String val = (String)xpath.compile(me.getKey()).evaluate(doc, XPathConstants.STRING);
             me.getValue().accept(val);
         }
     }

     private class XPathNSContext implements NamespaceContext {
         final Map<String,String> nsMap = new HashMap<>();

         {
             signatureInfo.getSignatureConfig().getNamespacePrefixes().forEach((k,v) -> nsMap.put(v,k));
             nsMap.put("dsss", MS_DIGSIG_NS);
             nsMap.put("ds", XML_DIGSIG_NS);
         }

         public String getNamespaceURI(String prefix) {
             return nsMap.get(prefix);
         }
         @SuppressWarnings("rawtypes")
         @Override
         public Iterator getPrefixes(String val) {
             return null;
         }
         public String getPrefix(String uri) {
             return null;
         }
     }
 }
	/* ====================================================================
	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.poi.poifs.crypt.dsig;

	import static org.apache.poi.ooxml.POIXMLTypeLoader.DEFAULT_XML_OPTIONS;
	import static org.apache.poi.poifs.crypt.dsig.facets.SignatureFacet.MS_DIGSIG_NS;
	import static org.apache.poi.poifs.crypt.dsig.facets.SignatureFacet.XML_DIGSIG_NS;

	import java.io.IOException;
	import java.security.cert.X509Certificate;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Map;
	import java.util.function.Consumer;

	import javax.xml.crypto.MarshalException;
	import javax.xml.crypto.URIDereferencer;
	import javax.xml.crypto.dsig.XMLSignature;
	import javax.xml.crypto.dsig.XMLSignatureException;
	import javax.xml.crypto.dsig.XMLSignatureFactory;
	import javax.xml.crypto.dsig.dom.DOMValidateContext;
	import javax.xml.namespace.NamespaceContext;
	import javax.xml.xpath.XPath;
	import javax.xml.xpath.XPathConstants;
	import javax.xml.xpath.XPathExpressionException;

	import org.apache.logging.log4j.LogManager;
	import org.apache.logging.log4j.Logger;
	import org.apache.poi.EncryptedDocumentException;
	import org.apache.poi.ooxml.util.DocumentHelper;
	import org.apache.poi.ooxml.util.XPathHelper;
	import org.apache.poi.openxml4j.opc.PackagePart;
	import org.apache.xmlbeans.XmlException;
	import org.w3.x2000.x09.xmldsig.SignatureDocument;
	import org.w3c.dom.Document;
	import org.w3c.dom.Element;
	import org.w3c.dom.NodeList;
	import org.xml.sax.SAXException;

	public class SignaturePart {
	private static final Logger LOG = LogManager.getLogger(SignaturePart.class);
	private static final String XMLSEC_VALIDATE_MANIFEST = "org.jcp.xml.dsig.validateManifests";


	private final PackagePart signaturePart;
	private final SignatureInfo signatureInfo;
	private X509Certificate signer;
	private List<X509Certificate> certChain;

	/* package */ SignaturePart(final PackagePart signaturePart, final SignatureInfo signatureInfo) {
	this.signaturePart = signaturePart;
	this.signatureInfo = signatureInfo;
	}

	/**
	* @return the package part containing the signature
	*/
	public PackagePart getPackagePart() {
	return signaturePart;
	}

	/**
	* @return the signer certificate
	*/
	public X509Certificate getSigner() {
	return signer;
	}

	/**
	* @return the certificate chain of the signer
	*/
	public List<X509Certificate> getCertChain() {
	return certChain;
	}

	/**
	* Helper method for examining the xml signature
	*
	* @return the xml signature document
	* @throws IOException if the xml signature doesn't exist or can't be read
	* @throws XmlException if the xml signature is malformed
	*/
	public SignatureDocument getSignatureDocument() throws IOException, XmlException {
	// TODO: check for XXE
	return SignatureDocument.Factory.parse(signaturePart.getInputStream(), DEFAULT_XML_OPTIONS);
	}

	/**
	* @return true, when the xml signature is valid, false otherwise
	*
	* @throws EncryptedDocumentException if the signature can't be extracted or if its malformed
	*/
	public boolean validate() {
	KeyInfoKeySelector keySelector = new KeyInfoKeySelector();
	XPath xpath = XPathHelper.getFactory().newXPath();
	xpath.setNamespaceContext(new XPathNSContext());

	try {
	Document doc = DocumentHelper.readDocument(signaturePart.getInputStream());
	NodeList nl = (NodeList)xpath.compile("//*[@Id]").evaluate(doc, XPathConstants.NODESET);
	final int length = nl.getLength();
	for (int i=0; i<length; i++) {
	((Element)nl.item(i)).setIdAttribute("Id", true);
	}

	DOMValidateContext domValidateContext = new DOMValidateContext(keySelector, doc);
	domValidateContext.setProperty(XMLSEC_VALIDATE_MANIFEST, Boolean.TRUE);

	URIDereferencer uriDereferencer = signatureInfo.getUriDereferencer();
	domValidateContext.setURIDereferencer(uriDereferencer);

	XMLSignatureFactory xmlSignatureFactory = signatureInfo.getSignatureFactory();
	XMLSignature xmlSignature = xmlSignatureFactory.unmarshalXMLSignature(domValidateContext);

	boolean valid = xmlSignature.validate(domValidateContext);

	if (valid) {
	signer = keySelector.getSigner();
	certChain = keySelector.getCertChain();
	extractConfig(doc, xmlSignature);
	}

	return valid;
	} catch (IOException e) {
	String s = "error in reading document";
	LOG.atError().withThrowable(e).log(s);
	throw new EncryptedDocumentException(s, e);
	} catch (SAXException e) {
	String s = "error in parsing document";
	LOG.atError().withThrowable(e).log(s);
	throw new EncryptedDocumentException(s, e);
	} catch (XPathExpressionException e) {
	String s = "error in searching document with xpath expression";
	LOG.atError().withThrowable(e).log(s);
	throw new EncryptedDocumentException(s, e);
	} catch (MarshalException e) {
	String s = "error in unmarshalling the signature";
	LOG.atError().withThrowable(e).log(s);
	throw new EncryptedDocumentException(s, e);
	} catch (XMLSignatureException e) {
	String s = "error in validating the signature";
	LOG.atError().withThrowable(e).log(s);
	throw new EncryptedDocumentException(s, e);
	}
	}

	private void extractConfig(final Document doc, final XMLSignature xmlSignature) throws XPathExpressionException {
	SignatureConfig signatureConfig = signatureInfo.getSignatureConfig();
	if (!signatureConfig.isUpdateConfigOnValidate()) {
	return;
	}

	signatureConfig.setSigningCertificateChain(certChain);
	signatureConfig.setSignatureMethodFromUri(xmlSignature.getSignedInfo().getSignatureMethod().getAlgorithm());

	final XPath xpath = XPathHelper.getFactory().newXPath();
	xpath.setNamespaceContext(new XPathNSContext());

	final Map<String,Consumer<String>> m = new HashMap<>();
	m.put("//mdssi:SignatureTime/mdssi:Value", signatureConfig::setExecutionTime);
	m.put("//xd:ClaimedRole", signatureConfig::setXadesRole);
	m.put("//dsss:SignatureComments", signatureConfig::setSignatureDescription);
	m.put("//xd:QualifyingProperties//xd:SignedSignatureProperties//ds:DigestMethod/@Algorithm", signatureConfig::setXadesDigestAlgo);
	m.put("//ds:CanonicalizationMethod", signatureConfig::setCanonicalizationMethod);

	for (Map.Entry<String,Consumer<String>> me : m.entrySet()) {
	String val = (String)xpath.compile(me.getKey()).evaluate(doc, XPathConstants.STRING);
	me.getValue().accept(val);
	}
	}

	private class XPathNSContext implements NamespaceContext {
	final Map<String,String> nsMap = new HashMap<>();

	{
	signatureInfo.getSignatureConfig().getNamespacePrefixes().forEach((k,v) -> nsMap.put(v,k));
	nsMap.put("dsss", MS_DIGSIG_NS);
	nsMap.put("ds", XML_DIGSIG_NS);
	}

	public String getNamespaceURI(String prefix) {
	return nsMap.get(prefix);
	}
	@SuppressWarnings("rawtypes")
	@Override
	public Iterator getPrefixes(String val) {
	return null;
	}
	public String getPrefix(String uri) {
	return null;
	}
	}
	}