使用公钥进行RSA-SHA256解密所需的C#代码

Question

我需要帮助来实现EWP(https://developers.erasmuswithoutpaper.eu/)。我已经建立了一些API，并使用EWP的在线验证工具来测试它们。现在一切都在工作，除了一件事：签名验证。

我有一些方法来检查请求标头是否有效。剩下的唯一方法是VerifySignature。我已经实现了日志记录，并有一个有效的签名和我应该用来解密它的公钥，但无论我尝试什么，我都没有从中获得任何可用的值

我收到的签名是：

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

公钥是在EWP管理的xml文件中找到的，使用的是我在请求中收到的keyId。由于我可以通过keyId找到公钥，我相信它是正确的：

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

现在我只需要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，看起来像这样：

(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文档指出签名是这样形成的：签名＝"；Base64(RSA-SHA256(签名字符串))

有人能给我看用这个公钥解密这个签名的代码吗，从而得到上面的签名字符串？(或者至少类似的东西)我已经为此挣扎了很长时间了。。。

编辑：所以我知道不可能从签名和公钥中获得原始消息，而只能从原始消息中生成哈希，我应该重新生成该哈希，看看它是否匹配。好吧，对我来说，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。

关于EWP使用的标准的更多文档：

https://github.com/erasmus-without-paper/ewp-specs-sec-cliauth-httpsig/tree/v1.0.1https://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API中实现了大量的测试登录，这些只是我从官方EWP在线验证程序中收到的值。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就是签名字符串，如下所述：https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures-07#section-3.1.2

我的代码在测试了更多之后(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));

第2版：我在日志中发现了一个工作测试但是，奇怪的是，它只起过一次作用。。。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.edun";
SigningString += "original-date: Wed, 09 Dec 2020 08:36:58 GMTn";
SigningString += "x-request-id: bc8da180-1217-4fe6-ac22-fc4919e96718n";
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;
}

但在我的API中，有了新数据、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语句：

现在我只需要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，看起来>像这样：

因此，消息摘要(SHA256是消息摘要或哈希算法)甚至签名都不是可逆加密的数据。它实际上是一个单向函数；hash"；或者由SHA256算法和RSA签名算法两者产生的消息摘要不可逆地返回到生成它的数据中。

请参见此处：https://www.cs.cornell.edu/courses/cs5430/2015sp/notes/rsa_sign_vs_dec.php

所以你真的不是"；解密"；签名。我相信您想要做的是获取已知的公钥并创建CCD_ 1的实例；签名"；以及"；sha256散列"；到CCD_ 2函数中，以返回签名是否与哈希匹配的布尔值。您可能也应该在您的端重新计算SHA256散列，以确保在报头中发送的内容实际上与"；有效载荷"；你收到了。仅仅根据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。

所以我使用了你提供的值：

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

下面是授权标头的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));
}
}

然而，该代码的输出返回"0"；错误"所以，你的帖子中似乎丢失了什么，或者这个例子来自哪里，可能是印刷错误？

作为概念的纯粹证明，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：

使用openssl genrsa 2048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

在上面的C#示例中需要注意的一点是，公钥和私钥是使用大字节数组和RSAParameters结构定义的。如果你想阅读(使用C#代码)你提供的base64 PEM编码的公钥，你要么需要使用.NET 5.0(因为微软似乎添加了从PEM格式加载密钥的函数)，要么你可能想通过NuGet引用类似BouncyCastle库的东西。更多信息请点击此处：http://www.bouncycastle.org/csharp/

否则，一旦RSACryptoServiceProvider被实例化并用公钥配置，对VerifyHash()或VerifyData()方法的简单调用将为您提供所需的布尔答案：https://learn.microsoft.com/en-us/dotnet/api/system.security.cryptography.rsacryptoserviceprovider.verifydata?view=net-5.0

VerifyData()方法将首先计算SHA256散列(假设为"halg"参数指定CryptoConfig.MapNameToOID("SHA256"))，然后验证生成的SHA256是否与生成签名的SHA256匹配。如果这是一个网络应用程序，我个人可能会采用以下方式：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，您可以到此为止(这样可以节省计算能力，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验证所述SHA256散列与签名。请记住，上面的例子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RFC草案或EWS网站上提到的其他RFC。你肯定想核实一下。然而，当我用PSS填充运行第一个代码示例时，它生成了一个异常，这让我确信它是PKCS1。