CMSSignedData 中的分离签名使用 Bouncy Castle 进行验证，但不使用 java.security.Signature

Question

我已经在网上浏览了几天以找到导致此问题的原因，但没有成功。

我正在这样做：

• 生成新证书（签名者证书及其父级）
• 使用 CMSSignedDataGenerator 创建签名（bouncycastle 1.45）
• 通过 java.security.Signature 验证 -> 失败
• 通过 BC 类验证 -> 成功

我发现的事实：

• 签名的创建和验证使用相同的算法 - SHA1withRSA。
• 在进程的任何地方都不会抛出异常。

问题：

• 知道我做错了什么吗？

需要考虑的想法：

我认为原因在于签名的生成，但我想我是根据文档进行的。或者 - 验证过程可能期望某种不同的结构，例如 PKCS1，而生成器提供 PKCS7。实际上没有什么能告诉我接下来要搜索什么。

这是一段代码，应该说明问题和输出（在提供您自己的证书和私钥之后）：

import org.bouncycastle.cms.*;
import org.bouncycastle.jce.provider.BouncyCastleProvider;

import java.security.PrivateKey;
import java.security.Security;
import java.security.Signature;
import java.security.cert.CertStore;
import java.security.cert.CollectionCertStoreParameters;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import static org.bouncycastle.cms.CMSSignedGenerator.DIGEST_SHA1;
import static org.bouncycastle.jce.provider.BouncyCastleProvider.PROVIDER_NAME;


public final class VerifyCMSSignedData {

    private static final byte[] DATA_TO_BE_SIGNED = "data".getBytes();
    private static final String SHA_1_WITH_RSA = "SHA1WithRSA";
    private static final boolean DATA_NOT_ATTACHED = false;
    private static final String COLLECTION_STORE_TYPE = "Collection";

    private static X509Certificate signer;
    private static PrivateKey signerPrivateKey;
    private static X509Certificate parent;

    private VerifyCMSSignedData() {
    }

    public static void main(String[] args) throws Exception {
        Security.addProvider(new BouncyCastleProvider());

        setUpCertificates();

        shouldVerifySignature();
    }

    public static void shouldVerifySignature() throws Exception {
        CMSSignedData signature = createSignature();

        shouldVerifyBySignature(signature.getEncoded());

        shouldVerifyByBC(signature.getEncoded());
    }

    private static void shouldVerifyByBC(byte[] signatureBytes) {
        boolean verified = false;

        try {
            CMSSignedData cms = new CMSSignedData(new CMSProcessableByteArray(DATA_TO_BE_SIGNED), signatureBytes);
            CertStore certStore = cms.getCertificatesAndCRLs(COLLECTION_STORE_TYPE, PROVIDER_NAME);
            SignerInformationStore signers = cms.getSignerInfos();
            Collection c = signers.getSigners();
            for (Object aC : c) {
                SignerInformation signer = (SignerInformation) aC;
                Collection certCollection = certStore.getCertificates(signer.getSID());
                Iterator certIt = certCollection.iterator();
                X509Certificate cert = (X509Certificate) certIt.next();
                verified = signer.verify(cert, PROVIDER_NAME);
            }
        } catch (Exception e) {
            e.printStackTrace();
            verified = false;
        }

        System.out.println(verified ? "VERIFIED BY BC" : "! Not verified through BC !");
    }

    private static void shouldVerifyBySignature(byte[] signatureBytes) throws Exception {
        Signature signatureVerifier = Signature.getInstance(SHA_1_WITH_RSA, PROVIDER_NAME);
        signatureVerifier.initVerify(signer.getPublicKey());
        signatureVerifier.update(DATA_TO_BE_SIGNED);
        boolean verified = signatureVerifier.verify(signatureBytes);

        System.out.println(verified ? "VERIFIED BY SIGNATURE CLASS" : "! Not verified by Signature class !");
    }

    private static CMSSignedData createSignature() throws Exception {
        CMSSignedDataGenerator gen = new CMSSignedDataGenerator();

        gen.addSigner(signerPrivateKey, signer, DIGEST_SHA1);

        List<X509Certificate> allCerts = new ArrayList<>();
        if (parent != null) {
            allCerts.add(parent);
        }
        allCerts.add(signer);

        CertStore store = CertStore.getInstance(
                COLLECTION_STORE_TYPE,
                new CollectionCertStoreParameters(allCerts),
                PROVIDER_NAME
        );

        gen.addCertificatesAndCRLs(store);

        return gen.generate(new CMSProcessableByteArray(DATA_TO_BE_SIGNED), DATA_NOT_ATTACHED, PROVIDER_NAME);
    }

    private static void setUpCertificates() throws Exception {
        // TODO setup your certificates here
    }
}

输出：

！未经签名类验证！

由 BC 验证

进程以退出代码 0 结束

Answer 1

您正在验证不同的事情。验证永远不会成功，因为 Java SHA1withRSA 验证需要 RSA PKCS#1_v15 签名，但您已生成 CMS 签名

CMS 封装了数字签名或加密消息以及一些附加元素，例如证书。您的 CMS 消息包含 PCKS#1 签名，但如果您想直接使用 Java Api 对其进行验证，请注意签名哈希不是根据要签名的数据计算的。它包含一些附加元素，例如在 ASN.1 语法中对签名证书的引用，因此您需要以相同的方式计算哈希

Answer 2

你错了：

signatureVerifier.update(DATA_TO_BE_SIGNED);

这里：

布尔验证 = signatureVerifier.verify(signatureBytes);

See pedrofb's answer for more details.

修改您的 shouldVerifyBySignature 方法以使其工作：

private static void shouldVerifyBySignature(byte[] signatureBytes) throws Exception {
    boolean verified = false;
    CMSSignedData cms = new CMSSignedData(new CMSProcessableByteArray(DATA_TO_BE_SIGNED), signatureBytes);
    CertStore certStore = cms.getCertificatesAndCRLs(COLLECTION_STORE_TYPE, PROVIDER_NAME);
    SignerInformationStore signers = cms.getSignerInfos();
    Collection c = signers.getSigners();
    for (Object aC : c) {
        SignerInformation si = (SignerInformation) aC;
        Signature signatureVerifier = Signature.getInstance(SHA_1_WITH_RSA, PROVIDER_NAME);
        signatureVerifier.initVerify(signer.getPublicKey());


        signatureVerifier.update(si.getEncodedSignedAttributes());
        verified = signatureVerifier.verify(si.getSignature());
    }

    System.out.println(verified ? "VERIFIED BY SIGNATURE CLASS" : "! Not verified by Signature class !");
}

希望对你有帮助！