如何解决在在线编译器中运行的 C# ECDSA 签名失败
我在我的 Windows 机器（Win 10 x64，运行 dotnet 4.7.2）上成功运行了这段代码。它生成一个 EC 密钥对（“P-256”），使用 SHA-256 对明文进行散列，使用 ec 私钥对散列进行签名，并使用 ec 公钥根据散列后的明文验证签名。
我得到这个输出所以一切正常：
EC signature curve secp256r1 / P-256 string
dataToSign: The quick brown fox jumps over the lazy dog
* * * sign the plaintext with the EC private key * * *
EC keysize: 256
signature (Base64): cwLBRSt1vtO33tHWcTdx1OTu9lBFXHEJgvdRyDUynLLE5eMakUZUAKLwaJvYoS7NBylx2Zz0+G6dvgJ6xv5qNA==
* * *verify the signature against hash of plaintext with the EC public key * * *
signature verified: True
现在我试图找到任何能够运行代码的在线编译器。我最喜欢的编译器 （https://repl.it/，Mono C# 编译器版本 6.8.0.123，完整代码：https://repl.it/@javacrypto/EcSignatureFull#main.cs）遇到此错误：
Unhandled Exception:
System.NotImplementedException: The method or operation is not implemented.
at EcSignatureString.Main () [0x00036] in <13e2ad358a924efc874a89efad35ffe7>:0
[ERROR] FATAL UNHANDLED EXCEPTION: System.NotImplementedException: The method or operation is not implemented.
at EcSignatureString.Main () [0x00036] in <13e2ad358a924efc874a89efad35ffe7>:0
exit status 1
使用另一个平台（https://dotnetfiddle.net/，编译器 .net 5，完整代码：https://dotnetfiddle.net/lSPpjz）会出现类似的错误：
Unhandled exception. System.PlatformNotSupportedException: Windows Cryptography Next Generation (CNG) is not supported on this platform.
at System.Security.Cryptography.ECDsaCng..ctor(Int32 keySize)
at EcSignatureString.Main()
Command terminated by signal 6
所以我的问题是：是否有任何可以运行代码的在线编译器？
我认为我的问题可能与 SO 无关 - 在这种情况下 - 是否还有其他堆栈交换站点更适合我的问题？
警告：以下代码没有异常处理，仅用于教育目的：
using System;
using System.Security.Cryptography;
class EcSignatureString {
static void Main() {
Console.WriteLine("EC signature curve secp256r1 / P-256 string");
string dataToSignString = "The quick brown fox jumps over the lazy dog";
byte[] dataToSign = System.Text.Encoding.UTF8.GetBytes(dataToSignString);
Console.WriteLine("dataToSign: " + dataToSignString);
try {
Console.WriteLine("\n* * * sign the plaintext with the EC private key * * *");
ECDsaCng ecDsaKeypair = new ECDsaCng(256);
Console.WriteLine("EC keysize: " + ecDsaKeypair.KeySize);
byte[] hashedData = null;
byte[] signature = null;
// create new instance of SHA256 hash algorithm to compute hash
HashAlgorithm hashAlgo = new SHA256Managed();
hashedData = hashAlgo.ComputeHash(dataToSign);
// sign Data using private key
signature = ecDsaKeypair.SignHash(hashedData);
string signatureBase64 = Convert.ToBase64String(signature);
Console.WriteLine("signature (Base64): " + signatureBase64);
// get public key from private key
string ecDsaPublicKeyParametersXml = ecDsaKeypair.ToXmlString(ECKeyXmlFormat.Rfc4050);
// verify
Console.WriteLine("\n* * *verify the signature against hash of plaintext with the EC public key * * *");
ECDsaCng ecDsaVerify = new ECDsaCng();
bool signatureVerified = false;
ecDsaVerify.FromXmlString(ecDsaPublicKeyParametersXml,ECKeyXmlFormat.Rfc4050);
signatureVerified = ecDsaVerify.VerifyHash(hashedData,signature);
Console.WriteLine("signature verified: " + signatureVerified);
}
catch(ArgumentNullException) {
Console.WriteLine("The data was not signed or verified");
}
}
}
解决方法
Microsoft 已决定加密和散列必须完全委托给操作系统（在 .NET Framework 中是一半），因此现在 .NET 5（和 .NET Core）有多个后端用于加密（例如 { {1}} 它具有使用 Windows 服务的 ECDsa 和使用 OpenSsl 的 Linux/MacOs 的 ECDsaCng（请参阅 MSDN）
现在...您的问题的解决方案是使用 ECDsaOpenSsl 类并让它选择其后端。它存在一些问题。您不能轻松地将密钥导出为 xml 格式，也不能轻松地将它们导出为 PEM 格式。您可以轻松地将它们导出为 ECDsa，并且可以轻松地从 PEM 格式导入它们。这并不是什么大问题，因为您很少需要生成密钥，通常您的程序从外部源接收其密钥，或者如果它自己生成它们，它可以将它们保存为二进制格式以便以后重用。
byte[]关于var dataToSignString = "Hello world!";
var dataToSign = Encoding.UTF8.GetBytes(dataToSignString);
Console.WriteLine("dataToSign: " + dataToSignString);
try
{
Console.WriteLine("\n* * * sign the plaintext with the EC private key * * *");
var ecDsaKeypair = ECDsa.Create(ECCurve.NamedCurves.nistP256);
// Normally here:
//ecDsaKeypair.ImportFromPem()
Console.WriteLine("EC keysize: " + ecDsaKeypair.KeySize);
byte[] hashedData = null;
byte[] signature = null;
// create new instance of SHA256 hash algorithm to compute hash
HashAlgorithm hashAlgo = new SHA256Managed();
hashedData = hashAlgo.ComputeHash(dataToSign);
// sign Data using private key
signature = ecDsaKeypair.SignHash(hashedData);
string signatureBase64 = Convert.ToBase64String(signature);
Console.WriteLine("signature (Base64): " + signatureBase64);
// get public key from private key
string ecDsaPublicKeyParameters = Convert.ToBase64String(ecDsaKeypair.ExportSubjectPublicKeyInfo());
// verify
Console.WriteLine("\n* * *verify the signature against hash of plaintext with the EC public key * * *");
var ecDsaVerify = ECDsa.Create(ECCurve.NamedCurves.nistP256);
bool signatureVerified = false;
// Normally here:
//ecDsaKeypair.ImportFromPem()
var publicKey = Convert.FromBase64String(ecDsaPublicKeyParameters);
ecDsaVerify.ImportSubjectPublicKeyInfo(publicKey,out _);
signatureVerified = ecDsaVerify.VerifyHash(hashedData,signature);
Console.WriteLine("signature verified: " + signatureVerified);
}
catch (ArgumentNullException)
{
Console.WriteLine("The data was not signed or verified");
}
、current comment on them on the github of .NET Core is：
From/ToXmlFormat嗯，从完成的一些测试来看，以 PEM 格式导出似乎很容易：
// There is currently not a standard XML format for ECC keys,so we will not implement the default
// To/FromXmlString so that we're not tied to one format when a standard one does exist. Instead we'll
// use an overload which allows the user to specify the format they'd like to serialize into.
然后
public static IEnumerable<string> Split(string str,int chunkSize)
{
for (int i = 0; i < str.Length; i += chunkSize)
{
yield return str.Substring(i,Math.Min(chunkSize,str.Length - i));
}
}
或
string b64privateKey = Convert.ToBase64String(ecDsaKeypair.ExportPkcs8PrivateKey());
b64privateKey = string.Join("\r\n",Split(b64privateKey,64));
string pemPrivateKey = "-----BEGIN PRIVATE KEY-----\r\n" + b64privateKey + "\r\n-----END PRIVATE KEY-----";
（请注意，我必须手动将字符串拆分为 64 个字符的块，这是 rfc7468 中给出的确切数字，因为 string b64publicKey = Convert.ToBase64String(ecDsaKeypair.ExportSubjectPublicKeyInfo());
b64publicKey = string.Join("\r\n",Split(b64publicKey,64));
string pemPublicKey = "-----BEGIN PUBLIC KEY-----\r\n" + b64publicKey + "\r\n-----END PUBLIC KEY-----";
仅支持 76 行长度）
版权声明：本文内容由互联网用户自发贡献，该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务，不拥有所有权，不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容， 请发送邮件至 dio@foxmail.com 举报，一经查实，本站将立刻删除。