.net 簽名加密實現的一種簡單方法

加密方法有很多，以下是其中一種簡單的簽名模式

1、首先客戶端通過webapi按照IP地址，時間戳，隨機數生成簽名，并傳遞序列號

private Result_Sign Valid()
        {
            string ServerIP = "192.168.1.6";// HttpContext.Request.ServerVariables.Get("Local_Addr").ToString(); //地址
            string timestamp = DateTimeToStamp(DateTime.Now); //時間戳

            string nonce = ST.WEB.App_Start.Common.CreateValidateCode(6);//隨機數
            string SignStr = SignatureString(ServerIP, timestamp, nonce);//生成簽名
            string appseq = ConfigurationManager.AppSettings["DPSeq"]; //產品序列號
            string Url = string.Format("http://www.abc.com:89/api/Valid?signature={0}&timestamp={1}&nonce={2}&appseq={3}", SignStr, timestamp, nonce, appseq);//POST發送URL
           
            string resStr = ST.WEB.App_Start.Common.Get_Http(Url, 12000);
            Result_Sign resJson = new Result_Sign()
                {
                    code = "-1",
                    message = ""
                };
            if (resStr.Substring(0, 2) != "錯誤")
            {
                resJson = JsonConvert.DeserializeObject<Result_Sign>(resStr);
            }
            return resJson;
 }

 // DateTime時間格式轉換為Unix時間戳格式
 private string DateTimeToStamp(DateTime time)
 {
      System.DateTime startTime = TimeZone.CurrentTimeZone.ToLocalTime(new System.DateTime(1970, 1, 1));
       return ((int)(time - startTime).TotalSeconds).ToString();
 }

//生成簽名串

 private string SignatureString(string appIP, string timestamp, string nonce)
 {
            string[] ArrTmp = { appIP, timestamp, nonce };

            Array.Sort(ArrTmp);
            string tmpStr = string.Join("", ArrTmp);

            tmpStr = FormsAuthentication.HashPasswordForStoringInConfigFile(tmpStr, "SHA1");
            return tmpStr.ToLower();
 }

//生成隨機數

 public static string CreateValidateCode(int length)
{
            int[] randMembers = new int[length];
            int[] validateNums = new int[length];
            string validateNumberStr = "";
            //生成起始序列值
            int seekSeek = unchecked((int)DateTime.Now.Ticks);
            Random seekRand = new Random(seekSeek);
            int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
            int[] seeks = new int[length];
            for (int i = 0; i < length; i++)
            {
                beginSeek += 10000;
                seeks[i] = beginSeek;
            }
            //生成隨機數字
            for (int i = 0; i < length; i++)
            {
                Random rand = new Random(seeks[i]);
                int pownum = 1 * (int)Math.Pow(10, length);
                randMembers[i] = rand.Next(pownum, Int32.MaxValue);
            }
            //抽取隨機數字
            for (int i = 0; i < length; i++)
            {
                string numStr = randMembers[i].ToString();
                int numLength = numStr.Length;
                Random rand = new Random();
                int numPosition = rand.Next(0, numLength - 1);
                validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
            }
            for (int i = 0; i < length; i++)
            {
                validateNumberStr += validateNums[i].ToString();
            }
            return validateNumberStr;
 }

        /// <summary>
        /// 獲取遠程服務器ATN結果
        /// </summary>
        /// <param name="strUrl">指定URL路徑地址</param>
        /// <param name="timeout">超時時間設置</param>
        /// <returns>服務器ATN結果</returns>
        public static string Get_Http(string strUrl, int timeout)
        {
            string strResult;
            try
            {
                HttpWebRequest myReq = (HttpWebRequest)HttpWebRequest.Create(strUrl);
                myReq.Timeout = timeout;
                HttpWebResponse HttpWResp = (HttpWebResponse)myReq.GetResponse();
                Stream myStream = HttpWResp.GetResponseStream();
                StreamReader sr = new StreamReader(myStream, Encoding.Default);
                StringBuilder strBuilder = new StringBuilder();
                while (-1 != sr.Peek())
                {
                    strBuilder.Append(sr.ReadLine());
                }
                strResult = strBuilder.ToString();
            }
            catch (Exception exp)
            {
                strResult = "錯誤：" + exp.Message;
            }
            return strResult;
        }
2、服務器端獲取數據并驗證返回結果

[HttpGet]
 public Result_Sign Sign(string signature, string timestamp, string nonce, string appseq)
 {
            Result_Sign sign = new Result_Sign()
            {
                  code="0",
                  message="fault"
            };
            if (Tool.ValidateSignature(signature, timestamp, nonce, appseq))
            {
                sign.code = "1";
                sign.message = "success";
            }
            return sign;

 }

        /// <summary>
        /// 檢查應用接入的數據完整性
        /// </summary>
        /// <param name="signature">加密簽名內容</param>
        /// <param name="timestamp">時間戳</param>
        /// <param name="nonce">隨機字符串</param>
        /// <param name="appseq">序列號</param>
        /// <returns></returns>
        public static  bool ValidateSignature(string signature, string timestamp, string nonce, string appseq)
        {
            bool result = false;
            Register item = Cache.GetBySeq(appseq);//獲取序列號相關信息
            if (item != null)
            {
                if (DateTime.Parse(item.ExpireDT) < DateTime.Now.Date) //是否過期
                {
                    return result;
                }
                #region 校驗簽名參數的來源是否正確
                string[] ArrTmp = { item.IP, timestamp, nonce };
                Array.Sort(ArrTmp);
                string tmpStr = string.Join("", ArrTmp);
                tmpStr = FormsAuthentication.HashPasswordForStoringInConfigFile(tmpStr, "SHA1");
                tmpStr = tmpStr.ToLower();
                if (tmpStr == signature && isNumberic(timestamp))
                { //驗證成功
                    DateTime dtTime =  StampToDateTime(timestamp);
                    double minutes = DateTime.Now.Subtract(dtTime).TotalMinutes;
                    if (minutes < 5) //時間不能大于5分鐘
                    {
                        result = true;
                    }
                }
                #endregion
            }
            return result;
}

 /// <summary>
 ///  時間戳轉時間
 /// </summary>
/// <param name="timeStamp"></param>
/// <returns></returns>
 private static DateTime StampToDateTime(string timeStamp)
 {
            DateTime dateTimeStart = TimeZone.CurrentTimeZone.ToLocalTime(new DateTime(1970, 1, 1));
            long lTime = long.Parse(timeStamp + "0000000");
            TimeSpan toNow = new TimeSpan(lTime);
            return dateTimeStart.Add(toNow);
 }

/// <summary>
/// 是否為數字
 /// </summary>
 /// <param name="message"></param>
 /// <returns></returns>
 protected static bool isNumberic(string message)
 {
            System.Text.RegularExpressions.Regex rex =
            new System.Text.RegularExpressions.Regex(@"^\d+$");

            if (rex.IsMatch(message))
            {

                return true;
            }
            else
                return false;
 }

public class Result_Sign
{
        public string code { set; get; }
        public string message { set; get; }

}