ApachePOI如何对数据进行数字签名。使用Java的docx文件

Question

如何对文件进行数字签名。使用java和签名的docx文件应嵌入在。docx文件。我使用了ApachePOIAPI，但无法进行数字签名。docx文件。需要哪种API以及如何使用

Answer 1

虽然这个问题已经很老了，但我想创建一个参考答案来链接。我不久前修改了e-Id applet代码，现在可以签名了

查看POIs documentation了解更多详细信息

基本代码如下：

// loading the keystore - pkcs12 is used here, but of course jks & co are also valid
// the keystore needs to contain a private key and it's certificate having a
// 'digitalSignature' key usage
char password[] = "test".toCharArray();
File file = new File("test.pfx");
KeyStore keystore = KeyStore.getInstance("PKCS12");
FileInputStream fis = new FileInputStream(file);
keystore.load(fis, password);
fis.close();

// extracting private key and certificate
String alias = "xyz"; // alias of the keystore entry
Key key = keystore.getKey(alias, password);
X509Certificate x509 = (X509Certificate)keystore.getCertificate(alias);

// filling the SignatureConfig entries (minimum fields, more options are available ...)
SignatureConfig signatureConfig = new SignatureConfig();
signatureConfig.setKey(keyPair.getPrivate());
signatureConfig.setSigningCertificateChain(Collections.singletonList(x509));
OPCPackage pkg = OPCPackage.open(..., PackageAccess.READ_WRITE);
signatureConfig.setOpcPackage(pkg);

// adding the signature document to the package
SignatureInfo si = new SignatureInfo();
si.setSignatureConfig(signatureConfig);
si.confirmSignature();
// optionally verify the generated signature
boolean b = si.verifySignature();
assert (b);
// write the changes back to disc
pkg.close();