$ openssl genrsa -out rsa_1024_priv.pem$ openssl pkcs8 -topk8 -inform PEM -in rsa_1024_priv.pem -outform PEM -nocrypt -out rsa_1024_priv_pkcs8.pem$ openssl rsa -in rsa_1024_priv_pkcs8.pem -pubout -out rsa_1024_pub.peml

public static class RSAHelper
{/// <summary>/// RSA签名/// </summary>/// <param name="content">数据</param>/// <param name="privateKey">RSA密钥</param>/// <returns></returns>public static string RsaSign(string content, string privateKey){var signer = SignerUtilities.GetSigner("SHA1withRSA");//将java格式的rsa密钥转换成.net格式var privateKeyParam = (RsaPrivateCrtKeyParameters)PrivateKeyFactory.CreateKey(StrToToHexByte(privateKey));signer.Init(true, privateKeyParam);var plainBytes = Encoding.UTF8.GetBytes(content);signer.BlockUpdate(plainBytes, 0, plainBytes.Length);var signBytes = signer.GenerateSignature();return ByteToHexStr(signBytes);}/// <summary>/// RSA验签/// </summary>/// <param name="content">内容</param>/// <param name="publicKey">RSA公钥</param>/// <param name="signData">签名字段</param>/// <returns></returns>public static bool VerifySign(string content, string publicKey, string signData){try{var signer = SignerUtilities.GetSigner("SHA1withRSA");var publicKeyParam = (RsaKeyParameters)PublicKeyFactory.CreateKey(StrToToHexByte(publicKey));signer.Init(false, publicKeyParam);var signBytes = StrToToHexByte(signData);var plainBytes = Encoding.UTF8.GetBytes(content);signer.BlockUpdate(plainBytes, 0, plainBytes.Length);var ret = signer.VerifySignature(signBytes);return ret;}catch (Exception ex){return false;}}/// <summary>/// 字符串转16进制字节数组/// </summary>/// <param name="hexString"></param>/// <returns></returns>private static byte[] StrToToHexByte(string hexString){hexString = hexString.Replace(" ", "");if ((hexString.Length % 2) != 0)hexString += " ";byte[] returnBytes = new byte[hexString.Length / 2];for (int i = 0; i < returnBytes.Length; i++)returnBytes[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);return returnBytes;}/// <summary>/// 字节数组转16进制字符串/// </summary>/// <param name="bytes"></param>/// <returns></returns>public static string ByteToHexStr(byte[] bytes){string returnStr = "";if (bytes != null){for (int i = 0; i < bytes.Length; i++){returnStr += bytes[i].ToString("X2");}}return returnStr;}
}

var content = "123";
var privateKey = RSAHelper.ByteToHexStr(Convert.FromBase64String("MIIBVQIBADANBgkqhkiG9w0BAQEFAASCAT8wggE7AgEAAkEA051JxQSrpN2cgI/fbCFjsALy7G055ichin5FF9qZ6VcdOa4/+V80FMLhR6ifRD2Sb/4qR0pMLnfkJadKBFM/QwIDAQABAkBMV3MUk6HEoXpjWwQUQ1tuVTIEH0eDA1zzVKhieaeK6Q1q4CiqJJ3fMkSTxgQZc6Wy11USJa6cRkYul4hsssddccBAiEA9Iiu7kxwbUE3DNnPzYi7st++fyo2ch9Wh2jF9BQB0YMCIQDdiXK/Y7673ucqBZdVpECJgp3DKCKlJPtfpuRmbSIvQQIhAM0IBdSclu+kbKoDvu7QpMCYRbuOA1Sw3fZvbPr4A4ZNAiBxcakpCNLrMcH+as6MNIg34oMXJL5ZAw8WdEgRi2EuAQIhALx6SB/hoTg91dGPd/Ql6pvRQaEG+HWda2yrW8fd41ot"));
var publicKey = RSAHelper.ByteToHexStr(Convert.FromBase64String("MFwwDQYJKoZIhvcNAQEBBQADSwAweniiO2ndANOdScUEq6TdnICP32whY7AC8uxtOeYnIYp+RRfamelXHTmuP/lfNBTC4Ueon0Q9km/+KkdKTC535CWnSgRTP0MCAwEAAQ=="));var signData = RSAHelper.RsaSign(content, privateKey);
var result= RSAHelper.VerifySign(content, publicKey, signData);