c++ - WIN32上的智威汤逊验证

Question

我正在尝试使用 WIN32 加密函数验证 RS512 JWT。我有公钥、要验证的数据和签名数据作为内存数组。我能够创建证书上下文并导入公钥，但到目前为止我还无法验证签名。无论我尝试什么，我都会得到一个 STATUS_INVALID_PARAMETER 结果。

我看过几篇关于必须反转部分或全部数据的帖子：

1. 反转公钥会阻止它加载。
2. 反转 dataBuffer 和 signatureBuffer 中的一个/两个仍然会导致 STATUS_INVALID_PARAMETER。

BCRYPT_ALG_HANDLE cryptAlg = nullptr;
if( BCRYPT_SUCCESS( BCryptOpenAlgorithmProvider( &cryptAlg, BCRYPT_RSA_ALGORITHM, nullptr, 0 ) ) )
{
    auto signingKeyBuffer = signingKey.publicKeyBuffer();
    PCCERT_CONTEXT cryptCert = CertCreateCertificateContext( X509_ASN_ENCODING, signingKeyBuffer.getBuffer(), signingKeyBuffer.getSize() );
    if( cryptCert != nullptr )
    {
        BCRYPT_KEY_HANDLE cryptKey;
        if( BCRYPT_SUCCESS( CryptImportPublicKeyInfoEx2( X509_ASN_ENCODING, &cryptCert->pCertInfo->SubjectPublicKeyInfo, 0, nullptr, &cryptKey ) ) )
        {
            BCRYPT_PKCS1_PADDING_INFO pkcs1Info;
            pkcs1Info.pszAlgId = BCRYPT_SHA512_ALGORITHM;
            auto dataBuffer = data;//.reversed();
            auto signatureBuffer = signature;//.reversed();
            auto status = BCryptVerifySignature( cryptKey, &pkcs1Info, dataBuffer.getBuffer(), dataBuffer.getSize(), signatureBuffer.getBuffer(), signatureBuffer.getSize(), BCRYPT_PAD_PKCS1 );

            //status is always STATUS_INVALID_PARAMETER here...
            
            BCryptDestroyKey( cryptKey );
        }
        CertFreeCertificateContext( cryptCert );
    }
    BCryptCloseAlgorithmProvider( cryptAlg, 0 );
}

Answer 1

我错过了文档中说数据需要散列的部分。在对数据（SHA512）应用相同的哈希后，我能够验证签名。这是工作代码减去错误检查：

//Hash data here.
auto hashedData = data.hash( HashType::SHA512 );

auto signingKeyBuffer = signingKey.publicKeyBuffer();
PCCERT_CONTEXT cryptCert = CertCreateCertificateContext( X509_ASN_ENCODING, signingKeyBuffer.getBuffer(), signingKeyBuffer.getSize() );
if( cryptCert != nullptr )
{
    BCRYPT_KEY_HANDLE cryptKey;
    if( BCRYPT_SUCCESS( CryptImportPublicKeyInfoEx2( X509_ASN_ENCODING, &cryptCert->pCertInfo->SubjectPublicKeyInfo, 0, nullptr, &cryptKey ) ) )
    {
        BCRYPT_PKCS1_PADDING_INFO pkcs1Info;
        pkcs1Info.pszAlgId = cNEHash::algorithmIdForHashType( cAlgorithmType::hashType( algorithm ) );
        auto status = BCryptVerifySignature( cryptKey, &pkcs1Info, hashedData.getBuffer(), hashedData.getSize(), signature.getBuffer(), signature.getSize(), BCRYPT_PAD_PKCS1 );
        if( BCRYPT_SUCCESS( status ) )
            verified = true;
        BCryptDestroyKey( cryptKey );
    }
    CertFreeCertificateContext( cryptCert );
}