c# - 使用公钥解密 RSA-SHA256 所需的 C# 代码

Question

我需要帮助来实施 EWP（https://developers.erasmuswithoutpaper.eu/）。我已经设置了一些 API 并使用 EWP 的在线验证器工具来测试它们。现在一切正常，除了一件事：签名验证。

我有几种方法可以通过请求标头检查它们是否有效。唯一剩下的方法是验证签名。我已经实现了日志记录，并且有一个有效的签名以及我应该用来解密它的公钥，但是无论我尝试什么，我都没有从中得到任何可用的价值。

我收到的签名是：

UiBgtTc4hIYeZehhP8RWKvPIvWFXeh7ERFEvJr43v87YE7I4dqAHbD8l5DwZW3jezVfIcBflBS7ezjFDOH0/43T21ZCxwa/0qKhQRTjXoWQSETap5fXI9MCtWcGcP5iNmnBang7zfIsr+DBqQU5N3vlCBLORGqGVM0eMEv8nwBanAM2J7ZjbIVg7gou22eHau9751M4OoQM5FCo3nBTRepf2XA0K4W00TJg55chjMW/s91rw2ryJSPLUlrhvl5kWUYozGO56SzRjNhW+/HawcNZRa+OioWvlLp4bYi8mFyjlWWNAXqKPbqROQILhJnlHjGeMMq2qZTbd3t8aGHpeDg==

使用我在请求中收到的 keyId，可以在 EWP 管理的 xml 文件中找到公钥。由于我可以通过 keyId 找到公钥，因此我确信它是正确的：

MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAkH+X94XHM5RDyTNETNmt8vuu1Q5leSpb
EMIru1WE/vte5Co8k9lluffhvGWeyZRCKH4kzIBHf5n/kKjftTvvT/mPwArnJFZXcRbT4ebZ66RE
hi/+uJkJbIQ2md43MJBjM6fSXZAUiNw8VP29yVhbVPV5UUIA2ddJfygk/4ZNOmxdgnEJdc3aJTsK
99dEJ6BYqbcxA0Bk19Fv3/azV0jGZgrC4Y2hx3A+NvIYC05QYoqNkcfDExRVrKwduVWzqz6XDt7C
9ERl5Ss2bsgm4gbDouJC+k+WoCcxkUO2tnxrsKxQtZetZZSvrkst/5ELBaJAvKpcq12CvnB09dY1
MBV2XwIDAQAB

现在我需要只用这个公钥解密签名（它是用与这个公钥匹配的私钥加密的），结果应该是一个签名字符串，如下所示：

(request-target): get /api/institutions?hei_id_param=uhasselt.be
date: Tue, 08 Dec 2020 15:27:05 GMT
digest: SHA-256=47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=
host: staging-ewp.uhasselt.be
x-request-id: 0e9b58f8-f98e-41a2-ae30-c09f566f437c

EWP 文档指出签名的形成方式如下：signature="Base64(RSA-SHA256(signing string))

谁能告诉我用这个公钥解密这个签名的代码，导致上面的签名字符串？（或至少类似的东西）我已经为此苦苦挣扎了很长时间......

编辑：所以我知道不可能从签名和公钥中获取原始消息，而只能从原始消息生成一个散列，我应该重现该散列以查看它是否匹配。对我来说好吧，我有这样做所需的所有数据，只是没有工作代码来获得匹配。

有关 EWP 使用的标准的更多文档：

https://github.com/erasmus-without-paper/ewp-specs-sec-cliauth-httpsig/tree/v1.0.1 https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures -07#section-2.5

关于我使用的测试数据：我在我的 API 中实现了很多日志记录以进行测试，这些只是我从官方 EWP 在线验证器收到的值。签名直接来自请求，公钥在 EWP 注册表 xml 中找到。我自己创建的唯一东西是签名字符串，如下所述：https ://datatracker.ietf.org/doc/html/draft-cavage-http-signatures-07#section-3.1.2

我的代码经过更多测试（requestContext.ClientPublicKey 是完整的字符串 MIIBIj...IDAQAB）：

requestContext.SigningString = GetSigningString(request, ref requestContext);
log.Info("Signing string: " + requestContext.SigningString);

string x509Pem = @"-----BEGIN PUBLIC KEY-----" + requestContext.ClientPublicKey + "-----END PUBLIC KEY-----";

byte[] message = Encoding.UTF8.GetBytes(requestContext.SigningString);
byte[] signature = Convert.FromBase64String(requestContext.Signature);

byte[] Sha256Message = SHA256.Create().ComputeHash(message);
string x = Convert.ToBase64String(Sha256Message);
log.Info("x = " + x);

PemReader pr = new PemReader(new StringReader(x509Pem));
AsymmetricKeyParameter publicKey = (AsymmetricKeyParameter)pr.ReadObject();

RSAParameters rsaParams = DotNetUtilities.ToRSAParameters((RsaKeyParameters)publicKey);
RSACng rsaCng = new RSACng();
rsaCng.ImportParameters(rsaParams);

bool verified = rsaCng.VerifyData(message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pss);
log.Info(verified);

log.Info(rsaCng.VerifyHash(Sha256Message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1));
log.Info(rsaCng.VerifyHash(Sha256Message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pss));
log.Info(rsaCng.VerifyHash(message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1));
log.Info(rsaCng.VerifyHash(message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pss));

string publicKeyXml = "<RSAKeyValue><Modulus>" + requestContext.ClientPublicKey + "</Modulus><Exponent>AQAB</Exponent></RSAKeyValue>";
log.Info("public key: " + publicKeyXml);

RSACryptoServiceProvider rsaCryptoServiceProvider = new RSACryptoServiceProvider();
rsaCryptoServiceProvider.FromXmlString(publicKeyXml);

log.Info(rsaCryptoServiceProvider.VerifyHash(Sha256Message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1));
log.Info(rsaCryptoServiceProvider.VerifyHash(Sha256Message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pss));
log.Info(rsaCryptoServiceProvider.VerifyHash(message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1));
log.Info(rsaCryptoServiceProvider.VerifyHash(message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pss));

Edit2：我在日志中发现了一个工作测试！但是，奇怪的是，它只工作了一次......我可以用这些相同的数据重现成功的验证：

private void test()
{
    string SigningString = "";
    string keyId = "769c7a9c8bac71a238ea9e78dda3e49bcabbaf695f56fbc99dd4d6e8f777756a";

    SigningString += "(request-target): get /api/institutions?hei_id=tul.edu\n";
    SigningString += "original-date: Wed, 09 Dec 2020 08:36:58 GMT\n";
    SigningString += "x-request-id: bc8da180-1217-4fe6-ac22-fc4919e96718\n";
    SigningString += "digest: SHA-256=47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=\n";
    SigningString += "host: staging-ewp.uhasselt.be";

    string Signature = "iqd5ZLHbzshwm3uClkKPpTniLqdQvodZAexEnywDEir9mfytcf8NDWBYi5bLrwf7jiZ29GO5F1CtlhstcqgO2Ia3LvLFbl4Dru58TzYasspsZtEr6r0HDFNNzfuVhWXSa349yJADGCDYbvAo3rBS7SM2lMZ9dpf8QZDOUL9wTUgpzt2X9IO83nmUxUQWYC9LQZJ5x/95RQsbXN4bY8lDFjfUAC2nW30g2SVtMKlpVXAZwLv7MoYlVXpFl56DuoOIGPmeH6LDumA6krU28EwK4vs1hbDr+GKpzQRvSKiabraUkTq3ITGeXhZgZy+0Av5KxCKNQOVjYiK3Hf0k8sAgpQ==";
    string ClientPublicKey = LookUpTheKey(keyId);

    Console.WriteLine("ClientPublicKey: " + ClientPublicKey);
    Console.WriteLine("Signing string: " + SigningString);

    string x509Pem = @"-----BEGIN PUBLIC KEY-----" + ClientPublicKey + "-----END PUBLIC KEY-----";

    byte[] message = Encoding.UTF8.GetBytes(SigningString);
    byte[] signature = Convert.FromBase64String(Signature);

    byte[] Sha256Message = SHA256.Create().ComputeHash(message);
    string x = Convert.ToBase64String(Sha256Message);
    Console.WriteLine("x = " + x);

    PemReader pr = new PemReader(new StringReader(x509Pem));
    AsymmetricKeyParameter publicKey = (AsymmetricKeyParameter)pr.ReadObject();

    RSAParameters rsaParams = DotNetUtilities.ToRSAParameters((RsaKeyParameters)publicKey);
    RSACng rsaCng = new RSACng();
    rsaCng.ImportParameters(rsaParams);

    Console.WriteLine(rsaCng.VerifyHash(Sha256Message, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1));
}

protected string LookUpTheKey(string keyId)
{
    string clientPublicKey = "";
    string registryPath = "registry.xml";
    if ((!File.Exists(registryPath)) || (Math.Abs((File.GetLastWriteTime(registryPath) - DateTime.Now).TotalMinutes) > minutesToChacheRegistry))
    {
        using (var handler = new HttpClientHandler())
        using (var client = new HttpClient(handler))
        {
            var request = new HttpRequestMessage(HttpMethod.Get, "https://dev-  registry.erasmuswithoutpaper.eu/catalogue-v1.xml");
            request.Headers.Add(HttpRequestHeader.Accept.ToString(), "application/xml");
            var response = client.SendAsync(request).Result;
            var returnedXml = response.Content.ReadAsStringAsync().Result;
            File.WriteAllText(registryPath, returnedXml);
        }
    }

    try
    {
        XmlDocument doc = new XmlDocument();
        doc.Load(registryPath);
        var namespaceManager = new XmlNamespaceManager(doc.NameTable);
        namespaceManager.AddNamespace("r", "https://github.com/erasmus-without- paper/ewp-specs-api-registry/tree/stable-v1");
        XmlNode root = doc.DocumentElement;
        var XPathExpr = @"//r:binaries/r:rsa-public-key[@sha-256=""" + keyId + @"""]";
        XmlNode node = root.SelectSingleNode(XPathExpr, namespaceManager);
        if (node == null) { }
        else { clientPublicKey = node.InnerText; }
    }
    catch
    {
    }
    return clientPublicKey;
}

但是在我的 API 中，使用新数据、其他 keyId、公钥、签名字符串和签名，它又失败了……这怎么可能？

Answer 1

您最初的困惑似乎在于以下陈述：

现在我需要只用这个公钥解密签名（它是用匹配这个公钥的 > 私钥加密的），结果应该是一个签名字符串，看起来 > 像这样：

因此消息摘要（SHA256 是消息摘要或散列算法）甚至签名都不是可逆加密的数据。它确实是一种单向函数，这意味着由 SHA256 算法和 RSA 签名算法生成的“哈希”或消息摘要不可逆地返回到生成它的数据中。

见这里： https ://www.cs.cornell.edu/courses/cs5430/2015sp/notes/rsa_sign_vs_dec.php

所以你真的没有“解密”那个签名。我相信您想要做的是获取已知的公钥并创建一个实例，RSACryptoServiceProvider然后将“签名”和“sha256 哈希”传递给VerifyHash()函数以获取签名是否与哈希匹配的布尔值。您可能还应该重新计算 SHA256 哈希，以确保标头中发送的内容实际上与您收到的“有效负载”相匹配。仅针对标头中的签名对标头中传递的 HASH 进行检查并不能保证它们的有效负载没有被更改/篡改。

所以我使用了您提供的值：

摘要（SHA256 哈希）：

47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=

签名（RSA）：

UiBgtTc4hIYeZehhP8RWKvPIvWFXeh7ERFEvJr43v87YE7I4dqAHbD8l5DwZW3jezVfIcBflBS7ezjFDOH0/43T21ZCxwa/0qKhQRTjXoWQSETap5fXI9MCtWcGcP5iNmnBang7zfIsr+DBqQU5N3vlCBLORGqGVM0eMEv8nwBanAM2J7ZjbIVg7gou22eHau9751M4OoQM5FCo3nBTRepf2XA0K4W00TJg55chjMW/s91rw2ryJSPLUlrhvl5kWUYozGO56SzRjNhW+/HawcNZRa+OioWvlLp4bYi8mFyjlWWNAXqKPbqROQILhJnlHjGeMMq2qZTbd3t8aGHpeDg==

公钥（PEM 格式）：

MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAkH+X94XHM5RDyTNETNmt8vuu1Q5leSpb
EMIru1WE/vte5Co8k9lluffhvGWeyZRCKH4kzIBHf5n/kKjftTvvT/mPwArnJFZXcRbT4ebZ66RE
hi/+uJkJbIQ2md43MJBjM6fSXZAUiNw8VP29yVhbVPV5UUIA2ddJfygk/4ZNOmxdgnEJdc3aJTsK
99dEJ6BYqbcxA0Bk19Fv3/azV0jGZgrC4Y2hx3A+NvIYC05QYoqNkcfDExRVrKwduVWzqz6XDt7C
9ERl5Ss2bsgm4gbDouJC+k+WoCcxkUO2tnxrsKxQtZetZZSvrkst/5ELBaJAvKpcq12CvnB09dY1
MBV2XwIDAQAB

并遵循授权标头的 RFC 草案： https ://datatracker.ietf.org/doc/html/draft-cavage-http-signatures-07#section-3.1

以下 C# 代码应尝试验证签名：

using System;
using System.Text;
using System.Security.Cryptography;

public static class SHA256WithRSATest
{
    /*
        Public Key:
            MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAkH+X94XHM5RDyTNETNmt8vuu1Q5leSpb
            EMIru1WE/vte5Co8k9lluffhvGWeyZRCKH4kzIBHf5n/kKjftTvvT/mPwArnJFZXcRbT4ebZ66RE
            hi/+uJkJbIQ2md43MJBjM6fSXZAUiNw8VP29yVhbVPV5UUIA2ddJfygk/4ZNOmxdgnEJdc3aJTsK
            99dEJ6BYqbcxA0Bk19Fv3/azV0jGZgrC4Y2hx3A+NvIYC05QYoqNkcfDExRVrKwduVWzqz6XDt7C
            9ERl5Ss2bsgm4gbDouJC+k+WoCcxkUO2tnxrsKxQtZetZZSvrkst/5ELBaJAvKpcq12CvnB09dY1
            MBV2XwIDAQAB

            Converted to an RSAParameters struct using Openssl:
            echo MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAkH+X94XHM5RDyTNETNmt8vuu1Q5leSpbEMIru1WE/vte5Co8k9lluffhvGWeyZRCKH4kzIBHf5n/kKjftTvvT/mPwArnJFZXcRbT4ebZ66REhi/+uJkJbIQ2md43MJBjM6fSXZAUiNw8VP29yVhbVPV5UUIA2ddJfygk/4ZNOmxdgnEJdc3aJTsK99dEJ6BYqbcxA0Bk19Fv3/azV0jGZgrC4Y2hx3A+NvIYC05QYoqNkcfDExRVrKwduVWzqz6XDt7C9ERl5Ss2bsgm4gbDouJC+k+WoCcxkUO2tnxrsKxQtZetZZSvrkst/5ELBaJAvKpcq12CvnB09dY1MBV2XwIDAQAB | base64 -d | openssl rsa -pubin -inform DER -noout -text
            RSA Public-Key: (2048 bit)
            Modulus:
                00:90:7f:97:f7:85:c7:33:94:43:c9:33:44:4c:d9:
                ad:f2:fb:ae:d5:0e:65:79:2a:5b:10:c2:2b:bb:55:
                84:fe:fb:5e:e4:2a:3c:93:d9:65:b9:f7:e1:bc:65:
                9e:c9:94:42:28:7e:24:cc:80:47:7f:99:ff:90:a8:
                df:b5:3b:ef:4f:f9:8f:c0:0a:e7:24:56:57:71:16:
                d3:e1:e6:d9:eb:a4:44:86:2f:fe:b8:99:09:6c:84:
                36:99:de:37:30:90:63:33:a7:d2:5d:90:14:88:dc:
                3c:54:fd:bd:c9:58:5b:54:f5:79:51:42:00:d9:d7:
                49:7f:28:24:ff:86:4d:3a:6c:5d:82:71:09:75:cd:
                da:25:3b:0a:f7:d7:44:27:a0:58:a9:b7:31:03:40:
                64:d7:d1:6f:df:f6:b3:57:48:c6:66:0a:c2:e1:8d:
                a1:c7:70:3e:36:f2:18:0b:4e:50:62:8a:8d:91:c7:
                c3:13:14:55:ac:ac:1d:b9:55:b3:ab:3e:97:0e:de:
                c2:f4:44:65:e5:2b:36:6e:c8:26:e2:06:c3:a2:e2:
                42:fa:4f:96:a0:27:31:91:43:b6:b6:7c:6b:b0:ac:
                50:b5:97:ad:65:94:af:ae:4b:2d:ff:91:0b:05:a2:
                40:bc:aa:5c:ab:5d:82:be:70:74:f5:d6:35:30:15:
                76:5f
            Exponent: 65537 (0x10001)
    */
    private static readonly RSAParameters PUBLIC_KEY = new RSAParameters
    {
        Modulus = new byte[]
        {
            0x90, 0x7f, 0x97, 0xf7, 0x85, 0xc7, 0x33, 0x94, 0x43, 0xc9,
            0x33, 0x44, 0x4c, 0xd9, 0xad, 0xf2, 0xfb, 0xae, 0xd5, 0x0e,
            0x65, 0x79, 0x2a, 0x5b, 0x10, 0xc2, 0x2b, 0xbb, 0x55, 0x84,
            0xfe, 0xfb, 0x5e, 0xe4, 0x2a, 0x3c, 0x93, 0xd9, 0x65, 0xb9,
            0xf7, 0xe1, 0xbc, 0x65, 0x9e, 0xc9, 0x94, 0x42, 0x28, 0x7e,
            0x24, 0xcc, 0x80, 0x47, 0x7f, 0x99, 0xff, 0x90, 0xa8, 0xdf,
            0xb5, 0x3b, 0xef, 0x4f, 0xf9, 0x8f, 0xc0, 0x0a, 0xe7, 0x24,
            0x56, 0x57, 0x71, 0x16, 0xd3, 0xe1, 0xe6, 0xd9, 0xeb, 0xa4,
            0x44, 0x86, 0x2f, 0xfe, 0xb8, 0x99, 0x09, 0x6c, 0x84, 0x36,
            0x99, 0xde, 0x37, 0x30, 0x90, 0x63, 0x33, 0xa7, 0xd2, 0x5d,
            0x90, 0x14, 0x88, 0xdc, 0x3c, 0x54, 0xfd, 0xbd, 0xc9, 0x58,
            0x5b, 0x54, 0xf5, 0x79, 0x51, 0x42, 0x00, 0xd9, 0xd7, 0x49,
            0x7f, 0x28, 0x24, 0xff, 0x86, 0x4d, 0x3a, 0x6c, 0x5d, 0x82,
            0x71, 0x09, 0x75, 0xcd, 0xda, 0x25, 0x3b, 0x0a, 0xf7, 0xd7,
            0x44, 0x27, 0xa0, 0x58, 0xa9, 0xb7, 0x31, 0x03, 0x40, 0x64,
            0xd7, 0xd1, 0x6f, 0xdf, 0xf6, 0xb3, 0x57, 0x48, 0xc6, 0x66,
            0x0a, 0xc2, 0xe1, 0x8d, 0xa1, 0xc7, 0x70, 0x3e, 0x36, 0xf2,
            0x18, 0x0b, 0x4e, 0x50, 0x62, 0x8a, 0x8d, 0x91, 0xc7, 0xc3,
            0x13, 0x14, 0x55, 0xac, 0xac, 0x1d, 0xb9, 0x55, 0xb3, 0xab,
            0x3e, 0x97, 0x0e, 0xde, 0xc2, 0xf4, 0x44, 0x65, 0xe5, 0x2b,
            0x36, 0x6e, 0xc8, 0x26, 0xe2, 0x06, 0xc3, 0xa2, 0xe2, 0x42,
            0xfa, 0x4f, 0x96, 0xa0, 0x27, 0x31, 0x91, 0x43, 0xb6, 0xb6,
            0x7c, 0x6b, 0xb0, 0xac, 0x50, 0xb5, 0x97, 0xad, 0x65, 0x94,
            0xaf, 0xae, 0x4b, 0x2d, 0xff, 0x91, 0x0b, 0x05, 0xa2, 0x40,
            0xbc, 0xaa, 0x5c, 0xab, 0x5d, 0x82, 0xbe, 0x70, 0x74, 0xf5,
            0xd6, 0x35, 0x30, 0x15, 0x76, 0x5f
        },
        Exponent = new byte[] { 0x01,0x00,0x01 }
    };


    public static readonly byte[] theSignature =
        Convert.FromBase64String("UiBgtTc4hIYeZehhP8RWKvPIvWFXeh7ERFEvJr43v87YE7I4dqAHbD8l5DwZW3jezVfIcBflBS7ezjFDOH0/43T21ZCxwa/0qKhQRTjXoWQSETap5fXI9MCtWcGcP5iNmnBang7zfIsr+DBqQU5N3vlCBLORGqGVM0eMEv8nwBanAM2J7ZjbIVg7gou22eHau9751M4OoQM5FCo3nBTRepf2XA0K4W00TJg55chjMW/s91rw2ryJSPLUlrhvl5kWUYozGO56SzRjNhW+/HawcNZRa+OioWvlLp4bYi8mFyjlWWNAXqKPbqROQILhJnlHjGeMMq2qZTbd3t8aGHpeDg==");

    public static readonly byte[] SHA256HASH =
        Convert.FromBase64String(
            "47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=");

    public static bool VerifyDigestSignature(
        byte[] digest, byte[] digestSignature)
    {
        using(RSACryptoServiceProvider rsaProvider =
                new RSACryptoServiceProvider())
        {
            rsaProvider.ImportParameters(PUBLIC_KEY);
            return rsaProvider.VerifyHash(
                digest, digestSignature, HashAlgorithmName.SHA256,
                    RSASignaturePadding.Pkcs1);
        }

    }

    public static void Main(string[] args)
    {
        Console.Error.WriteLine(
            VerifyDigestSignature(SHA256HASH,theSignature));

    }
}

但是，该代码的输出返回“False”。因此，您的帖子中是否丢失了某些内容，或者该示例的来源可能有印刷错误？

作为纯粹的概念证明，这里有类似的代码，它计算哈希和签名，然后使用 SHA256WithRSA 方法成功验证签名：

openssl genrsa 2048使用...生成了一个新的公钥/私钥对

using System;
using System.Text;
using System.Security.Cryptography;

public static class SHA256WithRSATest
{
    private static readonly RSAParameters PUBLIC_KEY = new RSAParameters
    {
        Modulus = new byte[]
        {
            0xc2, 0xdb, 0x06, 0xc3, 0xe0, 0x43, 0x3b, 0x38, 0x72,
            0x43, 0xc1, 0x87, 0xa4, 0x8b, 0x8c, 0x31, 0x64, 0x8a, 0xa4,
            0xf3, 0x0d, 0x96, 0xc9, 0x3c, 0x46, 0x5e, 0x16, 0x8a, 0x57,
            0xb6, 0x8c, 0x62, 0x0d, 0x3b, 0x78, 0x2f, 0xd8, 0x23, 0x6d,
            0x1a, 0x74, 0x0b, 0x1e, 0x7e, 0xd9, 0x44, 0xec, 0x74, 0x99,
            0xaf, 0x83, 0xe1, 0x84, 0x5c, 0x8b, 0x31, 0xac, 0x83, 0xe3,
            0x09, 0xc9, 0xff, 0xee, 0x29, 0xfd, 0xcd, 0x64, 0x34, 0x5b,
            0x25, 0xc7, 0xab, 0xf9, 0x76, 0x49, 0xcd, 0x1c, 0x53, 0xc4,
            0x82, 0xcb, 0x61, 0xfa, 0x87, 0xf5, 0xa7, 0xe4, 0x63, 0x03,
            0xbb, 0xbb, 0xb6, 0xc0, 0x2e, 0x5b, 0x1c, 0x28, 0xe6, 0xb8,
            0xba, 0x6e, 0x89, 0xf9, 0x5a, 0x15, 0xf7, 0x49, 0x63, 0x6b,
            0xb4, 0x90, 0x9c, 0xd5, 0xe8, 0xad, 0x5e, 0xa0, 0x95, 0x4b,
            0xf2, 0x9a, 0xaa, 0x29, 0x1e, 0x04, 0xfe, 0xc3, 0x8d, 0xea,
            0x41, 0xaf, 0xf8, 0x24, 0x7d, 0xf7, 0x3d, 0x24, 0x4d, 0xdd,
            0xcb, 0xad, 0x84, 0x94, 0xba, 0x32, 0xb8, 0x26, 0x3b, 0x48,
            0x55, 0xe2, 0x07, 0x13, 0x4d, 0x58, 0x1f, 0x61, 0x01, 0x92,
            0x40, 0x53, 0x23, 0x8f, 0x3d, 0x7d, 0x6a, 0x65, 0xe3, 0xb1,
            0xd3, 0xe3, 0x39, 0xd1, 0xd8, 0x77, 0xcd, 0x7d, 0x37, 0x9f,
            0x54, 0x76, 0x3f, 0xc3, 0x3f, 0x38, 0xe4, 0xab, 0xaf, 0x99,
            0x09, 0x1e, 0x96, 0x9d, 0x6e, 0x8e, 0x66, 0xb2, 0x5c, 0x39,
            0xee, 0xf7, 0x7e, 0x65, 0x89, 0x69, 0x9d, 0xdc, 0x20, 0xe7,
            0x63, 0x20, 0x75, 0x60, 0x75, 0x34, 0x22, 0x00, 0x2f, 0x74,
            0x5c, 0x4c, 0x0a, 0xdf, 0xb5, 0x12, 0xfa, 0x9d, 0xc1, 0xed,
            0x7f, 0x2e, 0xfc, 0xef, 0xd3, 0xb1, 0x62, 0x8a, 0xd7, 0x68,
            0x3c, 0xa6, 0x61, 0xa9, 0x3e, 0x9e, 0x27, 0x3c, 0x6e, 0x02,
            0xd1, 0x78, 0x0e, 0xe7, 0x8b, 0xb7, 0x91
        },
        Exponent = new byte[] { 0x01,0x00,0x01 }
    };

    private static readonly RSAParameters PRIVATE_KEY = new RSAParameters
    {
        Modulus = new byte[]
        {
            0xc2, 0xdb, 0x06, 0xc3, 0xe0, 0x43, 0x3b, 0x38, 0x72,
            0x43, 0xc1, 0x87, 0xa4, 0x8b, 0x8c, 0x31, 0x64, 0x8a, 0xa4,
            0xf3, 0x0d, 0x96, 0xc9, 0x3c, 0x46, 0x5e, 0x16, 0x8a, 0x57,
            0xb6, 0x8c, 0x62, 0x0d, 0x3b, 0x78, 0x2f, 0xd8, 0x23, 0x6d,
            0x1a, 0x74, 0x0b, 0x1e, 0x7e, 0xd9, 0x44, 0xec, 0x74, 0x99,
            0xaf, 0x83, 0xe1, 0x84, 0x5c, 0x8b, 0x31, 0xac, 0x83, 0xe3,
            0x09, 0xc9, 0xff, 0xee, 0x29, 0xfd, 0xcd, 0x64, 0x34, 0x5b,
            0x25, 0xc7, 0xab, 0xf9, 0x76, 0x49, 0xcd, 0x1c, 0x53, 0xc4,
            0x82, 0xcb, 0x61, 0xfa, 0x87, 0xf5, 0xa7, 0xe4, 0x63, 0x03,
            0xbb, 0xbb, 0xb6, 0xc0, 0x2e, 0x5b, 0x1c, 0x28, 0xe6, 0xb8,
            0xba, 0x6e, 0x89, 0xf9, 0x5a, 0x15, 0xf7, 0x49, 0x63, 0x6b,
            0xb4, 0x90, 0x9c, 0xd5, 0xe8, 0xad, 0x5e, 0xa0, 0x95, 0x4b,
            0xf2, 0x9a, 0xaa, 0x29, 0x1e, 0x04, 0xfe, 0xc3, 0x8d, 0xea,
            0x41, 0xaf, 0xf8, 0x24, 0x7d, 0xf7, 0x3d, 0x24, 0x4d, 0xdd,
            0xcb, 0xad, 0x84, 0x94, 0xba, 0x32, 0xb8, 0x26, 0x3b, 0x48,
            0x55, 0xe2, 0x07, 0x13, 0x4d, 0x58, 0x1f, 0x61, 0x01, 0x92,
            0x40, 0x53, 0x23, 0x8f, 0x3d, 0x7d, 0x6a, 0x65, 0xe3, 0xb1,
            0xd3, 0xe3, 0x39, 0xd1, 0xd8, 0x77, 0xcd, 0x7d, 0x37, 0x9f,
            0x54, 0x76, 0x3f, 0xc3, 0x3f, 0x38, 0xe4, 0xab, 0xaf, 0x99,
            0x09, 0x1e, 0x96, 0x9d, 0x6e, 0x8e, 0x66, 0xb2, 0x5c, 0x39,
            0xee, 0xf7, 0x7e, 0x65, 0x89, 0x69, 0x9d, 0xdc, 0x20, 0xe7,
            0x63, 0x20, 0x75, 0x60, 0x75, 0x34, 0x22, 0x00, 0x2f, 0x74,
            0x5c, 0x4c, 0x0a, 0xdf, 0xb5, 0x12, 0xfa, 0x9d, 0xc1, 0xed,
            0x7f, 0x2e, 0xfc, 0xef, 0xd3, 0xb1, 0x62, 0x8a, 0xd7, 0x68,
            0x3c, 0xa6, 0x61, 0xa9, 0x3e, 0x9e, 0x27, 0x3c, 0x6e, 0x02,
            0xd1, 0x78, 0x0e, 0xe7, 0x8b, 0xb7, 0x91
        },
        Exponent = new byte[] { 0x01,0x00,0x01 },
        D = new byte[]
        {
            0x01, 0xe9, 0x6a, 0x38, 0x93, 0xc3, 0xb5, 0x1a, 0x09, 0xac,
            0xf6, 0x82, 0x21, 0x30, 0x29, 0x50, 0xf6, 0xbe, 0x91, 0x7d,
            0xbc, 0xfd, 0x64, 0xbe, 0x0d, 0xa6, 0xb0, 0xab, 0xec, 0xce,
            0x62, 0xb4, 0x37, 0x93, 0x04, 0xcb, 0xdb, 0x60, 0x05, 0x9b,
            0x03, 0xd6, 0x74, 0x17, 0x24, 0x84, 0x93, 0x99, 0x55, 0x44,
            0xae, 0x93, 0x90, 0xdb, 0xe3, 0x95, 0xba, 0x2e, 0x95, 0x14,
            0xac, 0x81, 0xb1, 0x51, 0x82, 0x26, 0xf8, 0xbb, 0xb6, 0xc5,
            0x39, 0x1f, 0x4b, 0xd4, 0x48, 0x47, 0x15, 0xe7, 0x10, 0x7f,
            0x84, 0x05, 0x53, 0x12, 0xf0, 0x6b, 0x14, 0x47, 0x90, 0x6a,
            0xd0, 0x1d, 0xab, 0xe7, 0x08, 0x87, 0xcf, 0x32, 0xec, 0x4f,
            0x0f, 0xf4, 0x94, 0x98, 0xb8, 0xac, 0x73, 0x70, 0xe1, 0x46,
            0xa5, 0x40, 0x94, 0xac, 0xb2, 0xbe, 0xc1, 0xee, 0x95, 0x0f,
            0x2d, 0x4b, 0x4c, 0x19, 0xfa, 0x4c, 0x91, 0x98, 0x97, 0x75,
            0x79, 0x6e, 0x02, 0x9d, 0xe7, 0x96, 0xe5, 0x71, 0x74, 0x67,
            0x6b, 0x80, 0xc1, 0x5c, 0x30, 0x28, 0x78, 0xe6, 0x31, 0xdd,
            0x09, 0x2d, 0x55, 0xd3, 0x1c, 0xbf, 0x12, 0x39, 0xe1, 0x3b,
            0xf0, 0xd0, 0x92, 0xa0, 0x8e, 0xe4, 0x69, 0x2f, 0xb4, 0xe0,
            0x7e, 0x6d, 0x62, 0x00, 0xd4, 0xf4, 0x80, 0x0a, 0x5e, 0xcf,
            0xf3, 0x16, 0x59, 0x15, 0x0f, 0x96, 0xb5, 0x3b, 0xcd, 0xb3,
            0x4d, 0x3b, 0x0f, 0x58, 0xc1, 0xaf, 0xde, 0x7d, 0x11, 0x6f,
            0x53, 0x37, 0x24, 0x29, 0x12, 0xc6, 0xeb, 0x2e, 0x11, 0x74,
            0x93, 0x66, 0xbd, 0x42, 0xc2, 0x28, 0x35, 0x32, 0x1f, 0xef,
            0x95, 0x6b, 0x92, 0xe9, 0x7f, 0x9e, 0xc5, 0xbf, 0xf1, 0xfc,
            0x48, 0x07, 0x2f, 0xda, 0xe0, 0x6b, 0xaa, 0xdd, 0x02, 0xc9,
            0x4f, 0xe4, 0xff, 0x56, 0xc5, 0xfb, 0xe7, 0x1e, 0x63, 0x47,
            0xa1, 0x0d, 0x44, 0x0e, 0x22, 0x1d

        },
        P = new byte[] 
        {
            0xf1, 0x50, 0x52, 0x7e, 0x2b, 0xa7, 0xc3, 0x30, 0x26,
            0xda, 0x14, 0xaf, 0xf9, 0xc5, 0x21, 0x49, 0xab, 0xa8, 0x09,
            0x1f, 0x36, 0xe5, 0x1f, 0x0f, 0x52, 0x4d, 0x82, 0x41, 0x46,
            0x7e, 0x75, 0x43, 0x80, 0x8e, 0x58, 0x6f, 0xdf, 0x9d, 0xee,
            0x77, 0x4c, 0x9c, 0xff, 0x94, 0xf6, 0x90, 0xaa, 0xaf, 0x0f,
            0xba, 0xb6, 0x08, 0xe6, 0x3f, 0xaa, 0xf6, 0x37, 0xc5, 0xe3,
            0xf7, 0x6a, 0xcd, 0x1b, 0xb7, 0xa8, 0x78, 0x15, 0xfc, 0xd0,
            0xce, 0xe0, 0x67, 0xf5, 0xd7, 0xa2, 0xa7, 0x37, 0x6f, 0x95,
            0xeb, 0xe0, 0x13, 0x93, 0xc9, 0x65, 0xd8, 0x8b, 0x4e, 0x1c,
            0x46, 0xd8, 0x4f, 0x50, 0x6b, 0x02, 0x87, 0xb4, 0x4e, 0x55,
            0x6c, 0x21, 0xc3, 0xf5, 0xc7, 0xd9, 0x1d, 0x2a, 0xcd, 0x25,
            0x9a, 0xb4, 0x79, 0x28, 0x29, 0x03, 0x45, 0x11, 0x26, 0xce,
            0x76, 0x6c, 0xcb, 0x17, 0xb2, 0xc3, 0x58, 0x85, 0xe3
        },
        Q = new byte[]
        {
            0xce, 0xb6, 0xe2, 0x42, 0x9c, 0xe6, 0xd7, 0xc3, 0x52,
            0x83, 0x5f, 0xa7, 0x16, 0x04, 0x61, 0xf1, 0xb6, 0xf9, 0x65,
            0xb3, 0xda, 0x02, 0x10, 0x74, 0xc4, 0x67, 0x85, 0x5f, 0x1c,
            0x1f, 0xcb, 0x71, 0x0e, 0xe5, 0x10, 0x21, 0xd0, 0x5f, 0xbe,
            0xa4, 0x81, 0xcc, 0xdd, 0x52, 0xab, 0x6b, 0x40, 0x72, 0x09,
            0x9b, 0xa0, 0x4f, 0x2f, 0x88, 0x96, 0x54, 0xae, 0x66, 0x83,
            0xd5, 0x45, 0x48, 0xc7, 0x67, 0xaf, 0x5c, 0xc6, 0xfe, 0xb6,
            0x94, 0x26, 0x02, 0xf7, 0x1d, 0x41, 0x67, 0x98, 0x81, 0x1a,
            0x6a, 0xeb, 0xfb, 0x33, 0xc3, 0x34, 0x8a, 0x93, 0xbd, 0x74,
            0x4c, 0x7d, 0x1c, 0xc4, 0x38, 0x9d, 0x72, 0x6e, 0xe3, 0x79,
            0xd0, 0xec, 0xaf, 0xac, 0x14, 0xe2, 0xee, 0x27, 0x9c, 0x72,
            0xe6, 0xd8, 0x43, 0x6b, 0xc8, 0xae, 0x07, 0x5b, 0x5d, 0x27,
            0x61, 0xba, 0xa5, 0x7f, 0x74, 0xc8, 0x78, 0x66, 0xfb
        },
        DP = new byte[]
        {
            0x86, 0x46, 0x6e, 0x90, 0x9c, 0x54, 0x0e, 0x4d, 0x55,
            0xe1, 0x15, 0x8f, 0xd2, 0x08, 0xb9, 0xfc, 0x17, 0x53, 0x3a,
            0x38, 0x2f, 0x40, 0x90, 0xe6, 0xe2, 0xa2, 0x14, 0x6f, 0xa3,
            0xfd, 0x2b, 0xdc, 0xf2, 0xc4, 0xc2, 0x3b, 0x06, 0x10, 0x08,
            0x28, 0x43, 0xee, 0x3c, 0x5d, 0x34, 0x51, 0xcd, 0x57, 0xfa,
            0x05, 0xa7, 0xd3, 0x0d, 0xe3, 0xb1, 0x8a, 0xae, 0x00, 0x24,
            0x58, 0x81, 0x0a, 0x3e, 0x79, 0x14, 0x7a, 0x35, 0xa9, 0xe6,
            0xba, 0xa6, 0xad, 0xd2, 0x63, 0x39, 0xb3, 0x98, 0x2a, 0x34,
            0x1e, 0xfb, 0x21, 0x89, 0xa3, 0x90, 0x53, 0x4d, 0x38, 0x9a,
            0x8d, 0x65, 0x41, 0xc4, 0xfa, 0xb6, 0x7e, 0xb2, 0x7a, 0xc0,
            0x17, 0x9a, 0x36, 0x43, 0x26, 0x00, 0x0e, 0xb5, 0xc9, 0x4f,
            0x3a, 0x65, 0x5f, 0xe1, 0x53, 0xe8, 0xe8, 0xde, 0xa1, 0x5c,
            0x53, 0x13, 0x38, 0x73, 0x28, 0x5a, 0x80, 0x80, 0x87
        },
        DQ = new byte[]
        {
            0xc7, 0xe5, 0x24, 0x91, 0x84, 0x06, 0xdb, 0x19, 0x1f,
            0x9e, 0xb9, 0x0d, 0xeb, 0x85, 0x9b, 0x6d, 0x52, 0x22, 0x84,
            0x4d, 0xd2, 0x80, 0xf2, 0x86, 0xe8, 0x32, 0xaf, 0x4f, 0x94,
            0xf3, 0xce, 0x18, 0xeb, 0x6d, 0x69, 0x17, 0x39, 0xd8, 0x8c,
            0x93, 0xaa, 0x8d, 0x80, 0x6c, 0xe4, 0x25, 0x57, 0xf1, 0xaf,
            0x06, 0xd6, 0x94, 0x1c, 0x84, 0x39, 0xd3, 0x73, 0xbe, 0xe0,
            0xb7, 0x89, 0x43, 0x62, 0xc9, 0x0a, 0x54, 0x6e, 0x7e, 0x7b,
            0xf2, 0x71, 0x7b, 0xa6, 0x99, 0x9c, 0xd8, 0xe0, 0x29, 0xe0,
            0x71, 0x0a, 0xf8, 0x25, 0x4b, 0x1c, 0x70, 0xf1, 0x83, 0x60,
            0x86, 0x62, 0xea, 0x41, 0x79, 0xfa, 0x0f, 0x61, 0xda, 0x09,
            0xbf, 0x96, 0x52, 0x1e, 0xd7, 0x27, 0xc7, 0x63, 0x78, 0xaf,
            0xc8, 0x39, 0xd3, 0xa0, 0xd4, 0x34, 0x2e, 0x1b, 0x14, 0xce,
            0xf3, 0x7b, 0xb9, 0x74, 0xb2, 0x6a, 0xf5, 0xbb, 0xa7
        },
        InverseQ = new byte[]
        {
            0x83, 0x84, 0x1d, 0xa5, 0x91, 0x6a, 0xac, 0x17, 0xa3,
            0xaf, 0xb5, 0x1f, 0x36, 0x77, 0xcb, 0x9a, 0x05, 0x7a, 0x79,
            0xa3, 0x25, 0x77, 0xd9, 0x0e, 0x64, 0xdc, 0x18, 0xfd, 0xec,
            0xc6, 0xa4, 0xdc, 0x0f, 0x6a, 0x50, 0x91, 0x97, 0x12, 0xfe,
            0x05, 0x0b, 0xcd, 0x64, 0xf8, 0x6e, 0xbf, 0x12, 0x6b, 0xd2,
            0x0e, 0x7c, 0x94, 0xc2, 0x5b, 0x2d, 0x53, 0x0f, 0x45, 0x41,
            0xfb, 0x6b, 0x22, 0x64, 0xbb, 0x36, 0xc0, 0x24, 0x01, 0xe5,
            0x1b, 0xf7, 0x76, 0xa0, 0x3d, 0x67, 0x66, 0x2f, 0x6b, 0x80,
            0xb2, 0x35, 0x87, 0x68, 0xdb, 0x75, 0x4d, 0x3d, 0xc1, 0x21,
            0xa8, 0xff, 0x0d, 0xe7, 0xea, 0x2c, 0x87, 0xe1, 0xe5, 0xc1,
            0x81, 0x45, 0xd0, 0x2f, 0x6f, 0xbb, 0xe9, 0xbf, 0x1f, 0x93,
            0x62, 0x06, 0xf5, 0x2c, 0x78, 0xb0, 0x2a, 0x22, 0xb8, 0xeb,
            0xf8, 0xae, 0xdd, 0x1d, 0x25, 0x53, 0x66, 0xab, 0x94
        }
    };

    public const string SAMPLE_PAYLOAD =
        @"{ 'name': 'value', 'name2' : 'value2' }";


    public static byte[] GetDigest(byte[] message)
    {
        using (SHA256 digestAlg = SHA256.Create())
            return digestAlg.ComputeHash(message);
    }

    public static byte[] GetDigestSignature(byte[] digest)
    {
        using(RSACryptoServiceProvider rsaProvider =
                new RSACryptoServiceProvider())
        {
            rsaProvider.ImportParameters(PRIVATE_KEY);
            return rsaProvider.SignHash(digest, HashAlgorithmName.SHA256,
                    RSASignaturePadding.Pkcs1);
        }

    }

    public static bool VerifyDigestSignature(
        byte[] digest, byte[] digestSignature)
    {
        using(RSACryptoServiceProvider rsaProvider =
                new RSACryptoServiceProvider())
        {
            rsaProvider.ImportParameters(PUBLIC_KEY);
            return rsaProvider.VerifyHash(
                digest, digestSignature, HashAlgorithmName.SHA256,
                    RSASignaturePadding.Pkcs1);
        }

    }

    public static void Main(string[] args)
    {
        byte[] dataForSignature = Encoding.UTF8.GetBytes(SAMPLE_PAYLOAD);
        byte[] digest = GetDigest(dataForSignature);
        byte[] hashSignature = GetDigestSignature(digest);

        Console.WriteLine("The Sample Payload: {0}", SAMPLE_PAYLOAD);
        Console.WriteLine("SHA256 of Payload: {0}",
            Convert.ToBase64String(digest));
        Console.WriteLine("Signature of SHA256 of Payload: {0}",
            Convert.ToBase64String(hashSignature));
        Console.WriteLine("Verify RSA Signature of SHA256 Hash: {0}",
            VerifyDigestSignature(digest,hashSignature));

    }
}

执行结果：

The Sample Payload: { 'name': 'value', 'name2' : 'value2' }
SHA256 of Payload: Pw3YzEtDseyloxZGsfrFN1q8g39ubwlnRKJzal2sUb4=
Signature of SHA256 of Payload: rVdEq158Z8h9PHinlQ6I7lnUUcXDal25LZ+MIyW0Uvf8HpH6wRoQzqJhygVwHmeVTkZn2mZS644B/9Ey1WVbgq56zzk2XDiHyNnS1IeZvfaTkaXqiBszVQ/hTSjrDOARzrU2NDRo2/gI/UUXC2v2fx3eyd4NbztvghTKfoUBp+xZjyBHWlCwAtEmDfVT0/Di0LkrII80txrlHQpSNXEpejmrhJ10WsskUuOCOloQmcl8A5d0ibkXXqL6TLLWKpLS0wXI6+GZnlc6b3qL0rU1iDLQsYMHLvel6+DJzCvhV8FHn/yJNKwjNpFiSNektZBQovd4NgO9aBRNgxIOGEEqEA==
Verify RSA Signature of SHA256 Hash: True

在上述 C# 示例中需要注意的一件事是，公钥和私钥是使用大字节数组和 RSAParameters 结构定义的。如果您想阅读（使用 C# 代码）您提供的 base64 PEM 编码的公钥，您需要使用 .NET 5.0（因为微软似乎添加了从 PEM 格式加载密钥的功能），或者您可能想要通过 NuGet 引用类似 BouncyCastle 库的内容。更多信息在这里： http: //www.bouncycastle.org/csharp/

否则，一旦您使用公钥实例化并配置了 RSACryptoServiceProvider，只需调用 VerifyHash() 或 VerifyData() 方法即可获得所需的布尔答案：https ://docs.microsoft.com/en-us/dotnet /api/system.security.cryptography.rsacryptoserviceprovider.verifydata?view=net-5.0

该VerifyData()方法将首先计算 SHA256 哈希（假设您指定CryptoConfig.MapNameToOID("SHA256")对于“halg”参数），然后验证生成的 SHA256 与生成签名的那个相匹配。如果这是一个 Web 应用程序，我个人可能会采用以下方式处理它：计算有效负载的 SHA256 哈希。将其与 HTTP 标头中传递的 SHA256 进行比较。如果它们不匹配，您可以停在那里（从而节省计算能力，因为 RSA / 非对称加密有点昂贵）。如果它们确实匹配，则继续使用 RSA 使用签名验证所述 SHA256 哈希。请记住，上面的示例假设签名的填充方法是 PKCS1（我认为这更常见，但 PSS 是另一种选择）。我没有完全阅读 EWS 网站上提到的 RFC 草案或其他 RFC。您肯定会想要验证。然而，