我有一个创建 PDF 文档的 Base64 摘要的 API。现在我想创建另一个 API,它采用这个摘要和 PFX,并创建一个 ETSI.CAdES.detached 签名,并采用我想嵌入到我的 PDF 中的 LTV 信息(证书链、OCSP 响应、CRL)以获得 PAdES-LTV 签名使用第 3 个 API(我的第 3 个 API 将获取从此 API 获得的 CAdES 签名和 LTV 信息并将它们嵌入到我的 PDF 中)。我不知道如何使用该摘要和带有 Java 和 Bouncy 的 PFX 创建这个 ETSI.CAdES.detached 签名Castle.I 尝试遵循这个github教程。
1 回答
正如您所声明的,您有自己的代码来准备 PDF 以进行签名并将签名容器注入其中。因此,您的问题基本上可以归结为
如何使用 BouncyCastle 创建可用于创建 PAdES BASELINE B 或 T PDF 签名的 CAdES 签名容器?
在 iText 7 签名框架中的实现
由于我没有您现有的代码,我不得不为我的测试使用不同的框架。为此,我使用了 iText 7 签名框架。
BouncyCastle 确实包含一个CMSSignedDataGenerator
用于生成 CMS 签名的容器。
不幸的是,其中 SignerInfo 生成的默认实现与 CAdES/PAdES 不兼容,因为它不创建签名的 ESSCertID[v2] 属性。不过幸运的是,该实现旨在允许插入自定义属性集。
因此,您可以使用自定义的CMSSignedDataGenerator
.
因此,当您准备好要签名的 PDF 后,您可以这样进行:
InputStream data = [InputStream containing the PDF byte ranges to sign];
ContentSigner contentSigner = [BouncyCastle ContentSigner for your private key];
X509CertificateHolder x509CertificateHolder = [BouncyCastle X509CertificateHolder for your X.509 signer certificate];
DigestCalculatorProvider digestCalculatorProvider = new JcaDigestCalculatorProviderBuilder().setProvider("BC").build();
CMSTypedData msg = new CMSTypedDataInputStream(data);
CMSSignedDataGenerator gen = new CMSSignedDataGenerator();
gen.addSignerInfoGenerator(
new JcaSignerInfoGeneratorBuilder(digestCalculatorProvider)
.setSignedAttributeGenerator(new PadesSignedAttributeGenerator())
.setUnsignedAttributeGenerator(new PadesUnsignedAttributeGenerator())
.build(contentSigner, x509CertificateHolder));
gen.addCertificates(new JcaCertStore(Collections.singleton(x509CertificateHolder)));
CMSSignedData sigData = gen.generate(msg, false);
byte[] cmsBytes = sigData.getEncoded();
(PadesSignatureContainerBc方法sign
)
byte[] cmsBytes
包含要注入准备好的 PDF 签名占位符的字节。
需要以下辅助类:
首先是InputStream
包含要由 BouncyCastle 签名处理的 PDF 范围的包装器。
class CMSTypedDataInputStream implements CMSTypedData {
InputStream in;
public CMSTypedDataInputStream(InputStream is) {
in = is;
}
@Override
public ASN1ObjectIdentifier getContentType() {
return PKCSObjectIdentifiers.data;
}
@Override
public Object getContent() {
return in;
}
@Override
public void write(OutputStream out) throws IOException,
CMSException {
byte[] buffer = new byte[8 * 1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
in.close();
}
}
(PadesSignatureContainerBc辅助类CMSTypedDataInputStream
)
然后是为 PAdES 定制的签名属性生成器:
class PadesSignedAttributeGenerator implements CMSAttributeTableGenerator {
@Override
public AttributeTable getAttributes(@SuppressWarnings("rawtypes") Map params) throws CMSAttributeTableGenerationException {
String currentAttribute = null;
try {
ASN1EncodableVector signedAttributes = new ASN1EncodableVector();
currentAttribute = "SigningCertificateAttribute";
AlgorithmIdentifier digAlgId = (AlgorithmIdentifier) params.get(CMSAttributeTableGenerator.DIGEST_ALGORITHM_IDENTIFIER);
signedAttributes.add(createSigningCertificateAttribute(digAlgId));
currentAttribute = "ContentTypeAttribute";
ASN1ObjectIdentifier contentType = ASN1ObjectIdentifier.getInstance(params.get(CMSAttributeTableGenerator.CONTENT_TYPE));
signedAttributes.add(new Attribute(CMSAttributes.contentType, new DERSet(contentType)));
currentAttribute = "MessageDigestAttribute";
byte[] messageDigest = (byte[])params.get(CMSAttributeTableGenerator.DIGEST);
signedAttributes.add(new Attribute(CMSAttributes.messageDigest, new DERSet(new DEROctetString(messageDigest))));
return new AttributeTable(signedAttributes);
} catch (Exception e) {
throw new CMSAttributeTableGenerationException(currentAttribute, e);
}
}
Attribute createSigningCertificateAttribute(AlgorithmIdentifier digAlg) throws IOException, OperatorCreationException {
final IssuerSerial issuerSerial = getIssuerSerial();
DigestCalculator digestCalculator = digestCalculatorProvider.get(digAlg);
digestCalculator.getOutputStream().write(x509CertificateHolder.getEncoded());
final byte[] certHash = digestCalculator.getDigest();
if (OIWObjectIdentifiers.idSHA1.equals(digAlg.getAlgorithm())) {
final ESSCertID essCertID = new ESSCertID(certHash, issuerSerial);
SigningCertificate signingCertificate = new SigningCertificate(essCertID);
return new Attribute(id_aa_signingCertificate, new DERSet(signingCertificate));
} else {
ESSCertIDv2 essCertIdv2;
if (NISTObjectIdentifiers.id_sha256.equals(digAlg.getAlgorithm())) {
// SHA-256 is default
essCertIdv2 = new ESSCertIDv2(null, certHash, issuerSerial);
} else {
essCertIdv2 = new ESSCertIDv2(digAlg, certHash, issuerSerial);
}
SigningCertificateV2 signingCertificateV2 = new SigningCertificateV2(essCertIdv2);
return new Attribute(id_aa_signingCertificateV2, new DERSet(signingCertificateV2));
}
}
IssuerSerial getIssuerSerial() {
final X500Name issuerX500Name = x509CertificateHolder.getIssuer();
final GeneralName generalName = new GeneralName(issuerX500Name);
final GeneralNames generalNames = new GeneralNames(generalName);
final BigInteger serialNumber = x509CertificateHolder.getSerialNumber();
return new IssuerSerial(generalNames, serialNumber);
}
}
(PadesSignatureContainerBc辅助类PadesSignedAttributeGenerator
)
最后是用于签名时间戳的自定义无符号属性生成器:
class PadesUnsignedAttributeGenerator implements CMSAttributeTableGenerator {
@Override
public AttributeTable getAttributes(@SuppressWarnings("rawtypes") Map params) throws CMSAttributeTableGenerationException {
if (tsaClient == null)
return null;
try {
ASN1EncodableVector unsignedAttributes = new ASN1EncodableVector();
byte[] signature = (byte[])params.get(CMSAttributeTableGenerator.SIGNATURE);
byte[] timestamp = tsaClient.getTimeStampToken(tsaClient.getMessageDigest().digest(signature));
unsignedAttributes.add(new Attribute(id_aa_signatureTimeStampToken, new DERSet(ASN1Primitive.fromByteArray(timestamp))));
return new AttributeTable(unsignedAttributes);
} catch (Exception e) {
throw new CMSAttributeTableGenerationException("", e);
}
}
}
(PadesSignatureContainerBc辅助类PadesUnsignedAttributeGenerator
)
在这里,我假设一个ITSAClient tsaClient
iText 7 时间戳请求客户端。您当然可以使用您选择的任意 RFC 3161 时间戳请求客户端。
如果您已将私钥读入 JCA/JCE ,则可以使用 BouncyCastlePrivateKey pk
创建所需的密钥,例如:ContentSigner contentSigner
JcaContentSignerBuilder
ContentSigner contentSigner = new JcaContentSignerBuilder("SHA512withRSA").build(pk);
(比较SignPadesBctestSignPadesBaselineT
中的测试)
PDFBox 3 签名框架中的实现
同时,您在评论中表示您正在研究使用 PDFBox 进行签名。幸运的是,上面提供的代码几乎无需更改即可与 PDFBox 一起使用。
要将上面的代码与 PDFBox 一起使用,只需将其包装到 PDFBoxSignatureInterface
框架中:
public class PadesSignatureContainerBc implements SignatureInterface {
public PadesSignatureContainerBc(X509CertificateHolder x509CertificateHolder, ContentSigner contentSigner, TSAClient tsaClient) throws OperatorCreationException {
this.contentSigner = contentSigner;
this.tsaClient = tsaClient;
this.x509CertificateHolder = x509CertificateHolder;
digestCalculatorProvider = new JcaDigestCalculatorProviderBuilder().setProvider("BC").build();
}
@Override
public byte[] sign(InputStream content) throws IOException {
try {
CMSTypedData msg = new CMSTypedDataInputStream(content);
CMSSignedDataGenerator gen = new CMSSignedDataGenerator();
gen.addSignerInfoGenerator(
new JcaSignerInfoGeneratorBuilder(digestCalculatorProvider)
.setSignedAttributeGenerator(new PadesSignedAttributeGenerator())
.setUnsignedAttributeGenerator(new PadesUnsignedAttributeGenerator())
.build(contentSigner, x509CertificateHolder));
gen.addCertificates(new JcaCertStore(Collections.singleton(x509CertificateHolder)));
CMSSignedData sigData = gen.generate(msg, false);
return sigData.getEncoded();
} catch (OperatorCreationException | GeneralSecurityException | CMSException e) {
throw new IOException(e);
}
}
final ContentSigner contentSigner;
final X509CertificateHolder x509CertificateHolder;
final TSAClient tsaClient;
final DigestCalculatorProvider digestCalculatorProvider;
class CMSTypedDataInputStream implements CMSTypedData {
InputStream in;
public CMSTypedDataInputStream(InputStream is) {
in = is;
}
@Override
public ASN1ObjectIdentifier getContentType() {
return PKCSObjectIdentifiers.data;
}
@Override
public Object getContent() {
return in;
}
@Override
public void write(OutputStream out) throws IOException,
CMSException {
byte[] buffer = new byte[8 * 1024];
int read;
while ((read = in.read(buffer)) != -1) {
out.write(buffer, 0, read);
}
in.close();
}
}
class PadesSignedAttributeGenerator implements CMSAttributeTableGenerator {
@Override
public AttributeTable getAttributes(@SuppressWarnings("rawtypes") Map params) throws CMSAttributeTableGenerationException {
String currentAttribute = null;
try {
ASN1EncodableVector signedAttributes = new ASN1EncodableVector();
currentAttribute = "SigningCertificateAttribute";
AlgorithmIdentifier digAlgId = (AlgorithmIdentifier) params.get(CMSAttributeTableGenerator.DIGEST_ALGORITHM_IDENTIFIER);
signedAttributes.add(createSigningCertificateAttribute(digAlgId));
currentAttribute = "ContentType";
ASN1ObjectIdentifier contentType = ASN1ObjectIdentifier.getInstance(params.get(CMSAttributeTableGenerator.CONTENT_TYPE));
signedAttributes.add(new Attribute(CMSAttributes.contentType, new DERSet(contentType)));
currentAttribute = "MessageDigest";
byte[] messageDigest = (byte[])params.get(CMSAttributeTableGenerator.DIGEST);
signedAttributes.add(new Attribute(CMSAttributes.messageDigest, new DERSet(new DEROctetString(messageDigest))));
return new AttributeTable(signedAttributes);
} catch (Exception e) {
throw new CMSAttributeTableGenerationException(currentAttribute, e);
}
}
Attribute createSigningCertificateAttribute(AlgorithmIdentifier digAlg) throws IOException, OperatorCreationException {
final IssuerSerial issuerSerial = getIssuerSerial();
DigestCalculator digestCalculator = digestCalculatorProvider.get(digAlg);
digestCalculator.getOutputStream().write(x509CertificateHolder.getEncoded());
final byte[] certHash = digestCalculator.getDigest();
if (OIWObjectIdentifiers.idSHA1.equals(digAlg.getAlgorithm())) {
final ESSCertID essCertID = new ESSCertID(certHash, issuerSerial);
SigningCertificate signingCertificate = new SigningCertificate(essCertID);
return new Attribute(id_aa_signingCertificate, new DERSet(signingCertificate));
} else {
ESSCertIDv2 essCertIdv2;
if (NISTObjectIdentifiers.id_sha256.equals(digAlg.getAlgorithm())) {
// SHA-256 is default
essCertIdv2 = new ESSCertIDv2(null, certHash, issuerSerial);
} else {
essCertIdv2 = new ESSCertIDv2(digAlg, certHash, issuerSerial);
}
SigningCertificateV2 signingCertificateV2 = new SigningCertificateV2(essCertIdv2);
return new Attribute(id_aa_signingCertificateV2, new DERSet(signingCertificateV2));
}
}
public IssuerSerial getIssuerSerial() {
final X500Name issuerX500Name = x509CertificateHolder.getIssuer();
final GeneralName generalName = new GeneralName(issuerX500Name);
final GeneralNames generalNames = new GeneralNames(generalName);
final BigInteger serialNumber = x509CertificateHolder.getSerialNumber();
return new IssuerSerial(generalNames, serialNumber);
}
}
class PadesUnsignedAttributeGenerator implements CMSAttributeTableGenerator {
@Override
public AttributeTable getAttributes(@SuppressWarnings("rawtypes") Map params) throws CMSAttributeTableGenerationException {
if (tsaClient == null)
return null;
try {
ASN1EncodableVector unsignedAttributes = new ASN1EncodableVector();
byte[] signature = (byte[])params.get(CMSAttributeTableGenerator.SIGNATURE);
byte[] timestamp = tsaClient.getTimeStampToken(new ByteArrayInputStream(signature)).getEncoded();
unsignedAttributes.add(new Attribute(id_aa_signatureTimeStampToken, new DERSet(ASN1Primitive.fromByteArray(timestamp))));
return new AttributeTable(unsignedAttributes);
} catch (Exception e) {
throw new CMSAttributeTableGenerationException("", e);
}
}
}
}
(PDFBox PadesSignatureContainerBc的实现SignatureInterface
)
你可以像这样使用它
try ( PDDocument pdDocument = Loader.loadPDF(SOURCE_PDF) )
{
SignatureInterface signatureInterface = new PadesSignatureContainerBc(new X509CertificateHolder(chain[0].getEncoded()),
new JcaContentSignerBuilder("SHA512withRSA").build(pk),
new TSAClient(new URL("http://timestamp.server/rfc3161endpoint"), null, null, MessageDigest.getInstance("SHA-256")));
PDSignature signature = new PDSignature();
signature.setFilter(COSName.getPDFName("MKLx_PAdES_SIGNER"));
signature.setSubFilter(COSName.getPDFName("ETSI.CAdES.detached"));
signature.setName("Example User");
signature.setLocation("Los Angeles, CA");
signature.setReason("Testing");
signature.setSignDate(Calendar.getInstance());
pdDocument.addSignature(signature);
ExternalSigningSupport externalSigning = pdDocument.saveIncrementalForExternalSigning(RESULT_OUTPUT);
// invoke external signature service
byte[] cmsSignature = signatureInterface.sign(externalSigning.getContent());
// set signature bytes received from the service
externalSigning.setSignature(cmsSignature);
}
(PDFBox SignPadesBc测试testSignPadesBaselineT
)