我们有创建 PKCS1 v2.1 数字签名的客户端应用程序(Applets 和 Silverlight)。数字签名被创建为 PKCS1,因为原始内容没有下载到客户端,只有内容的哈希被发送到客户端以节省带宽。
我们正在尝试创建一个 PKCS7/CMS 容器服务器端,based on the information from this post :
但是,当进入第 5 步和第 6 步时,事情就中断了,因为 BC CMSSignedGenerator 和 CMSSignedData 类不支持在没有私钥的情况下添加签名者:
CMS创建:
// Add BC to environment
Security.addProvider(new BouncyCastleProvider());
// Read certificate and convert to X509Certificate
CertificateFactory certFactory = CertificateFactory.getInstance("X.509");
Path certPath = Paths.get("C:\\MyCertificate.cer");
byte[] certData = Files.readAllBytes(certPath);
InputStream in = new ByteArrayInputStream(certData);
X509Certificate cert = (X509Certificate)certFactory.generateCertificate(in);
// Add signer certificates to List and add them to store
List<X509Certificate> certList = new ArrayList<X509Certificate>();
certList.add(cert);
Store certs = new JcaCertStore(certList);
// Get signature in Base64, decode and convert to byte array
// Signature signature = Signature.getInstance("SHA1WithRSA", "BC");
String signatureBase64 = "gjTbsD0vSOi6nMlRVbpTLRQ5j+g2h8iEH1DgQx93PDBuwzWT47urKxMAS+75dAhQrkreLt9TGZaDN85e5xEpIF12mK1G+AgCNc370I1bjxOvUU67IVxHkZ+IX8kzSiD2uNuQtk3IrwUqyL30TIo+LDAXmY1AQVZwXAaOYG4bXxI=";
BASE64Decoder decoder = new BASE64Decoder();
byte[] signatureByte = decoder.decodeBuffer(signatureBase64);
// Instantiate new ANS1ObjectIdentifier to identify PKCS1 signature
ASN1ObjectIdentifier asn1OidPkcs1 = new ASN1ObjectIdentifier("1.2.840.113549.1.1");
// Table generator
/*AttributeTable attrT = new AttributeTable();
SimpleAttributeTableGenerator sAttrTGen = new SimpleAttributeTableGenerator();*/
// Instantiate new CMSProcessable object
CMSTypedData msg = new CMSProcessableByteArray(asn1OidPkcs1, signatureByte);
// Instantiate new CMSSignedDataGenerator object
CMSSignedDataGenerator gen = new CMSSignedDataGenerator();
// ContentSigner sha1Signer = new JcaContentSignerBuilder("SHA1withRSA").setProvider("BC").s
gen.addCertificates(certs);
CMSSignedData sigData = gen.generate(msg, false);
// BASE64Encoder encoder = new BASE64Encoder();
new File("C:\\MyCMS.p7s");
FileOutputStream fileOuputStream = new FileOutputStream("C:\\Users\\gregwerner\\Documents\\Archivos\\miFirma.p7s");
fileOuputStream.write(sigData.getEncoded());
fileOuputStream.flush();
fileOuputStream.close();
}
关于如何完成 CMS 容器的任何想法?也许使用 AttributeTable 为时间戳等添加多个 OID,但这似乎也不起作用。
最佳答案
看了这个引用项目https://code.google.com/p/j4ops/ 找到了答案.本指南也有很大帮助,尽管它专门处理使用 iText 的 PDF,这些 PDF 使用来自加密操作的 BC:http://itextpdf.com/book/digitalsignatures20130304.pdf .诀窍是通过实现使用例如 sign(byte[] toEncrypt) 方法的 Signer 接口(interface)将签名操作委托(delegate)给外部提供者(PKCS11、PKCS12 等)。这样,可以设置提供程序,然后只需调用 sign 方法并将有关如何签名的实现细节留给提供程序本身。
Bouncy CaSTLe 使用带有 SignerInf 内部类的 CMSSignedDataGenerator 类来分别构建 CMS 容器和签名者信息。所以诀窍是构建一个不需要私钥的 SignerInf 对象,因为 sign() 操作应该委托(delegate)给提供者。特别是在使用智能卡时,私钥甚至可能不可用。此外,在对哈希进行签名和构建 CMS 容器时,需要考虑需要添加为签名属性和/或未签名属性的信息。所以这些是解决问题的基本步骤:
// Build the items to encrypt, objects for method parameters would be obtained previously.
byte[] toEncrypt = externalSignerInfoGenerator.getCmsBytesToSign(hash,
signingTime,
PKCSObjectIdentifiers.data,
x509Cert,
timeStampToken,
ocsp);
// The externalSignerInfoGenerator.getCmsBytesToSign is a method from a re implemention of the
// SignerInf inner class from CMSSignedDataGenerator and is used to get a byte array from an
// org.bouncycastle.asn1.ASN1EncodableVector. To build the vector one should add attributes to
// their corresponding OID's using the org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers interface,
// for example:
ASN1EncodableVector signedAttrVector = buildSignedAttributes (hash, signingTime, contentType,
x509Cert, ocspResp);
// This would call the buildSignedAttributes method to build the signed attributes vector
ASN1EncodableVector signedAttrVector = new ASN1EncodableVector();
// Add CMS attributes
signedAttrVector.add (new Attribute(CMSAttributes.contentType, new DERSet (contentType)));
signedAttrVector.add (new Attribute (CMSAttributes.signingTime, new DERSet(new Time (signingTime))));
signedAttrVector.add(new Attribute(CMSAttributes.messageDigest, new DERSet(new DEROctetString(hash))));
// Not all attributes are considered in BC's CMSAttributes interface, therefore one would have to add
// an additional step:
signedAttrVector.add(buildOcspResponseAttribute(ocspResp));
// This method would call buildOcspResponseAttribute to add the object as a PKCSObjectIdentifier
protected Attribute buildOcspResponseAttribute (byte[] ocspResp) throws IOException, CMSException {
return new Attribute (PKCSObjectIdentifiers.id_aa_ets_revocationRefs,
new DERSet(DERUtil.readDERObject(ocspResp)));
}
// Call sign method from provider, such as PKCS11, PKCS12, etc.
byte [] signature = getSignProvider().sign(toEncrypt);
// Now build standard org.bouncycastle.cms.SignerInfoGenerator with hash, signed data
// and certificate to add to CMS, create attached or detached signature
// create signed envelope
CMSSignedData envdata = externalCMSSignedDataGenerator.generate(false);
byte[] enveloped = envdata.getEncoded();
关于java - 使用 Java 将外部 PKCS1 字节数组和证书添加到 CMS 容器,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22470156/