使用.Net签名并使用OpenSSL命令验证

using System;
using System.Security.Cryptography;

public class DigitalSignatureExample
{
    public static byte[] SignData(byte[] data, RSAParameters privateKey)
    {
        using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
        {
            rsa.ImportParameters(privateKey);
            return rsa.SignData(data, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
        }
    }

    public static bool VerifyData(byte[] data, byte[] signature, RSAParameters publicKey)
    {
        using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
        {
            rsa.ImportParameters(publicKey);
            return rsa.VerifyData(data, signature, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
        }
    }

    public static void Main()
    {
        string data = "Hello, world!";
        byte[] dataBytes = System.Text.Encoding.UTF8.GetBytes(data);

        // 生成密钥对
        using (RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
        {
            RSAParameters privateKey = rsa.ExportParameters(true);
            RSAParameters publicKey = rsa.ExportParameters(false);

            // 使用私钥签名数据
            byte[] signature = SignData(dataBytes, privateKey);

            // 使用公钥验证签名
            bool isValid = VerifyData(dataBytes, signature, publicKey);

            Console.WriteLine("Signature is valid: " + isValid);
        }
    }
}

openssl rsa -pubout -outform PEM -in private_key.pem -out public_key.pem

openssl dgst -sha256 -verify public_key.pem -signature signature.bin data.txt