将org.dom4j.Document转换为org.w3c.dom.Document和XML签名的问题

Question

我有一些类已经使用DOM4J来读取XML文件并为数据提供getter方法.现在,我需要添加检查XML数字签名的可能性.

使用org.w3c.dom并关注http://java.sun.com/developer/technicalArticles/xml/dig_signature_api/ 一切正常.

所以,我尝试使用DOMWriter从org.dom4j.Document转换为org.w3c.dom.Document,但在此之后签名验证不起作用.我认为这是因为DOMWiter正在改变XML树(正如doc4.asXML()似乎显示的那样).

我试图找到要设置的东西以保持文档的完整性,但DOMWriter没有这样的方法.

下面是演示非对称转换的代码.

用于测试的文件是http://www.robertodiasduarte.com.br/files/nfe/131090007910044_v1.10-procNFe.xml

有人知道这个的原因/解决方法吗？

谢谢(抱歉我的英语不好).

package testevalidanfe;

import java.io.File;
import java.io.FileWriter;
import java.io.PrintWriter;
import javax.swing.JOptionPane;
import javax.xml.crypto.dsig.XMLSignature;
import javax.xml.crypto.dsig.XMLSignatureFactory;
import javax.xml.crypto.dsig.dom.DOMValidateContext;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.dom4j.io.XMLWriter;
import org.w3c.dom.Document;
import org.w3c.dom.Node;

public class Testevalidanfe {

    public static void main(String[] args) throws Exception {
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        dbf.setNamespaceAware(true);
        DocumentBuilder db = dbf.newDocumentBuilder();
        Document d = db.parse("exemplo-nfe.xml");

        Node no = d.getElementsByTagNameNS(XMLSignature.XMLNS, "Signature").item(0);

        DOMValidateContext valContext = new DOMValidateContext(new X509KeySelector(), no);
        XMLSignatureFactory fac = XMLSignatureFactory.getInstance("DOM");
        XMLSignature signature = fac.unmarshalXMLSignature(valContext);

        JOptionPane.showMessageDialog(null, "Validation using org.w3c.dom: " + signature.validate(valContext));
        org.dom4j.io.DOMReader domreader = new org.dom4j.io.DOMReader();
        org.dom4j.Document doc4 = domreader.read(d);
        org.dom4j.io.DOMWriter domwriter = new org.dom4j.io.DOMWriter();
        d = domwriter.write(doc4);

        String after = doc4.asXML();

        PrintWriter writer = new PrintWriter(new File("after-convertion.xml"));
        writer.print(after);
        writer.close();

        no = d.getElementsByTagNameNS(XMLSignature.XMLNS, "Signature").item(0);

        valContext = new DOMValidateContext(new X509KeySelector(), no);
        fac = XMLSignatureFactory.getInstance("DOM");
        signature = fac.unmarshalXMLSignature(valContext);

        JOptionPane.showMessageDialog(null, "Validation after convert: " + signature.validate(valContext));
    }
}

package testevalidanfe;

import java.security.Key;
import java.security.PublicKey;
import java.security.cert.X509Certificate;
import java.util.Iterator;
import javax.xml.crypto.AlgorithmMethod;
import javax.xml.crypto.KeySelector;
import javax.xml.crypto.KeySelectorException;
import javax.xml.crypto.KeySelectorResult;
import javax.xml.crypto.XMLCryptoContext;
import javax.xml.crypto.XMLStructure;
import javax.xml.crypto.dsig.SignatureMethod;
import javax.xml.crypto.dsig.keyinfo.KeyInfo;
import javax.xml.crypto.dsig.keyinfo.X509Data;

public class X509KeySelector extends KeySelector {
    public KeySelectorResult select(KeyInfo keyInfo,
                                KeySelector.Purpose purpose,
                                AlgorithmMethod method,
                                XMLCryptoContext context)
    throws KeySelectorException {
        Iterator ki = keyInfo.getContent().iterator();
        while (ki.hasNext()) {
            XMLStructure info = (XMLStructure) ki.next();
            if (!(info instanceof X509Data))
                continue;
            X509Data x509Data = (X509Data) info;
            Iterator xi = x509Data.getContent().iterator();
            while (xi.hasNext()) {
                Object o = xi.next();
                if (!(o instanceof X509Certificate))
                    continue;
                final PublicKey key = ((X509Certificate)o).getPublicKey();
                if (algEquals(method.getAlgorithm(), key.getAlgorithm())) {
                    return new KeySelectorResult() {
                        public Key getKey() { return key; }
                    };
                }
           }
       }
       throw new KeySelectorException("No key found!");
    }

    static boolean algEquals(String algURI, String algName) {
        if ((algName.equalsIgnoreCase("DSA") &&
            algURI.equalsIgnoreCase(SignatureMethod.DSA_SHA1)) ||
            (algName.equalsIgnoreCase("RSA") &&
            algURI.equalsIgnoreCase(SignatureMethod.RSA_SHA1))) {
            return true;
        } else {
            return false;
        }
    }
}

例如,如果原始XML以以下内容开头:

<nfeProc versao="1.10" xmlns="http://www.portalfiscal.inf.br/nfe">
<NFe xmlns="http://www.portalfiscal.inf.br/nfe">
<infNFe Id="NFe31090807301671000131550010001000216008030809" versao="1.10" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
...

doc4.asXML()返回:

<nfeProc xmlns="http://www.portalfiscal.inf.br/nfe" versao="1.10">
<NFe>
<infNFe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Id="NFe31090807301671000131550010001000216008030809" versao="1.10">
...

Answer 1

我仔细研究了这一点，结果发现 DOM4J DOMWriter 正在做一些奇怪的命名空间，这显然混淆了规范化过程。我还没有指出确切的原因，但我认为这与 DOMWriter 在 DOM 元素中插入额外的 xmlns 属性有关。如果您打开 XML 数字签名 API 的日志记录（如您所引用的文章中所述），您可以看到效果，规范化的 <SignedInfo> 元素在 DOM4J 生成的 DOM 文档中缺少名称空间声明。

但是，您可以使用 DOM4J DocumentSource 和 DOMResult 通过转换生成 DOM 文档，而不是使用 DOMWriter。

/**
 * Create a DOM document from a DOM4J document 
 */
static Document copy(org.dom4j.Document orig) {
    try {
        TransformerFactory tf = TransformerFactory.newInstance();
        Transformer t = tf.newTransformer();
        DOMResult result = new DOMResult();
        t.transform(new DocumentSource(orig), result);
        return (Document) result.getNode();
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}

使用生成的 DOM 文档进行验证。