C# 私钥加密,公钥解密
/// <summary> /// RSA加密的密匙结构 公钥和私匙 /// </summary> public struct RSAKey { public string PublicKey { get; set; } public string PrivateKey { get; set; } } #region 得到RSA的解谜的密匙对 /// <summary> /// 得到RSA的解谜的密匙对 /// </summary> /// <returns></returns> public static RSAKey GetRASKey() { RSACryptoServiceProvider.UseMachineKeyStore = true; //声明一个指定大小的RSA容器 RSACryptoServiceProvider rsaProvider = new RSACryptoServiceProvider(); //取得RSA容易里的各种参数 RSAParameters p = rsaProvider.ExportParameters(true); return new RSAKey() { PublicKey = ComponentKey(p.Exponent, p.Modulus), PrivateKey = ComponentKey(p.D, p.Modulus) }; } #endregion #region 组合解析密匙 /// <summary> /// 组合成密匙字符串 /// </summary> /// <param name="b1"></param> /// <param name="b2"></param> /// <returns></returns> private static string ComponentKey(byte[] b1, byte[] b2) { List<byte> list = new List<byte>(); //在前端加上第一个数组的长度值 这样今后可以根据这个值分别取出来两个数组 list.Add((byte)b1.Length); list.AddRange(b1); list.AddRange(b2); byte[] b = list.ToArray(); return Convert.ToBase64String(b); } /// <summary> /// 解析密匙 /// </summary> /// <param name="key">密匙</param> /// <param name="b1">RSA的相应参数1</param> /// <param name="b2">RSA的相应参数2</param> private static void ResolveKey(string key, out byte[] b1, out byte[] b2) { //从base64字符串 解析成原来的字节数组 byte[] b = Convert.FromBase64String(key); //初始化参数的数组长度 b1 = new byte[b[0]]; b2 = new byte[b.Length - b[0] - 1]; //将相应位置是值放进相应的数组 for (int n = 1, i = 0, j = 0; n < b.Length; n++) { if (n <= b[0]) { b1[i++] = b[n]; } else { b2[j++] = b[n]; } } } #endregion #region 字符串加密解密 公开方法 /// <summary> /// 字符串加密 /// </summary> /// <param name="source">源字符串 明文</param> /// <param name="key">密匙</param> /// <returns>加密遇到错误将会返回原字符串</returns> public static string EncryptString(string source, string key) { string encryptString = string.Empty; byte[] d; byte[] n; try { //if (!CheckSourceValidate(source)) //{ // throw new Exception("source string too long"); //} //解析这个密钥 ResolveKey(key, out d, out n); BigInteger biN = new BigInteger(n); BigInteger biD = new BigInteger(d); encryptString = EncryptString(source, biD, biN); } catch { encryptString = source; } return encryptString; } /// <summary> /// 字符串解密 /// </summary> /// <param name="encryptString">密文</param> /// <param name="key">密钥</param> /// <returns>遇到解密失败将会返回原字符串</returns> public static string DecryptString(string encryptString, string key) { string source = string.Empty; byte[] e; byte[] n; try { //解析这个密钥 ResolveKey(key, out e, out n); BigInteger biE = new BigInteger(e); BigInteger biN = new BigInteger(n); source = DecryptString(encryptString, biE, biN); } catch { source = encryptString; } return source; } #endregion #region 字符串加密解密 私有 实现加解密的实现方法 /// <summary> /// 用指定的密匙加密 /// </summary> /// <param name="source">明文</param> /// <param name="d">可以是RSACryptoServiceProvider生成的D</param> /// <param name="n">可以是RSACryptoServiceProvider生成的Modulus</param> /// <returns>返回密文</returns> private static string EncryptString(string source, BigInteger d, BigInteger n) { int len = source.Length; int len1 = 0; int blockLen = 0; if ((len % 128) == 0) len1 = len / 128; else len1 = len / 128 + 1; string block = ""; StringBuilder result = new StringBuilder(); for (int i = 0; i < len1; i++) { if (len >= 128) blockLen = 128; else blockLen = len; block = source.Substring(i * 128, blockLen); byte[] oText = System.Text.Encoding.Default.GetBytes(block); BigInteger biText = new BigInteger(oText); BigInteger biEnText = biText.modPow(d, n); string temp = biEnText.ToHexString(); result.Append(temp).Append("@"); len -= blockLen; } return result.ToString().TrimEnd('@'); } /// <summary> /// 用指定的密匙加密 /// </summary> /// <param name="source">密文</param> /// <param name="e">可以是RSACryptoServiceProvider生成的Exponent</param> /// <param name="n">可以是RSACryptoServiceProvider生成的Modulus</param> /// <returns>返回明文</returns> private static string DecryptString(string encryptString, BigInteger e, BigInteger n) { StringBuilder result = new StringBuilder(); string[] strarr1 = encryptString.Split(new char[] { '@' }, StringSplitOptions.RemoveEmptyEntries); for (int i = 0; i < strarr1.Length; i++) { string block = strarr1[i]; BigInteger biText = new BigInteger(block, 16); BigInteger biEnText = biText.modPow(e, n); string temp = System.Text.Encoding.Default.GetString(biEnText.getBytes()); result.Append(temp); } return result.ToString(); } #endregion
备注:BigInteger类爆红,在nuget里面搜索引用。