RSA 签名认证

开发中遇到某个模块的表单需要发布给匿名用户填写，想到了RSA签名对URL进行签名处理来做，代码很多，贴上的是符合自己开发的，需要注意的是Convert.FromBase64String这个函数的传参，用PrivateKey对发布的URL参数Content进行签名，再用PublicKey验证签名，需要注意对PublicKey和PrivateKey的理解。

首先生成PrivateKey和PublicKey，代码如下：

/// <summary>  
    /// RSA产生密钥  
    /// </summary>  
    /// <param name="xmlKeys">私钥</param>  
    /// <param name="xmlPublicKey">公钥</param>  
    public void RSAKey(out string xmlKeys, out string xmlPublicKey)  
    {  
        try  
        {  
            System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();  
            xmlKeys = rsa.ToXmlString(true);  
            xmlPublicKey = rsa.ToXmlString(false);  
        }  
        catch (Exception ex)  
        {  
            throw ex;  
        }  
    }  

签名代码如下：

 #region RSA 签名验证
        /// <summary>
        /// RSA签名
        /// </summary>
        /// <param name="privateKey">私钥</param>
        /// <param name="content">需签名的数据</param>
        /// <returns>签名后的值</returns>
        public static string SignatureFormatter(string privateKey, string content) {
            var hashData = GetHash(content);
            RSACryptoServiceProvider key = new RSACryptoServiceProvider();
            key.FromXmlString(privateKey);
            RSAPKCS1SignatureFormatter formatter = new RSAPKCS1SignatureFormatter(key);
            formatter.SetHashAlgorithm("SHA1");
            byte[] inArray = formatter.CreateSignature(hashData);
            return Convert.ToBase64String(inArray).Replace("/", "_");
        }

        /// <summary>
        /// RSA验证
        /// </summary>
        /// <param name="publicKey">公钥</param>
        /// <param name="hashData">Hash描述</param>
        /// <param name="signature">签名后的结果</param>
        /// <returns></returns>
        public static bool ValidateSignature(string publicKey, byte[] hashData, string signature) {
            RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(publicKey);
            RSAPKCS1SignatureDeformatter rsaDeformatter = new RSAPKCS1SignatureDeformatter(rsa);
            rsaDeformatter.SetHashAlgorithm("SHA1");
            var deformatterData = Convert.FromBase64String(signature);
            return rsaDeformatter.VerifySignature(hashData, deformatterData);
        }

        /// <summary>
        /// Hash算法
        /// </summary>
        /// <param name="content"></param>
        /// <returns></returns>
        public static byte[] GetHash(string content) {
            var buffer = Encoding.GetEncoding("UTF-8").GetBytes(content);
            var sha = HashAlgorithm.Create("SHA1");
            return sha?.ComputeHash(buffer);
        }
        #endregion

最后在请求表单时做认证

/// <summary>
        /// 获取专项信息
        /// </summary>
        /// <param name="detailId"></param>
        /// <param name="signCode"></param>
        /// <returns></returns>
        [Route("get-zxjc-task/{detailId}/{signCode}"), HttpGet, AllowAnonymous]
        public ApiResultModel<SaveZxjcDetailModel> GetZxjcTaskModel(string detailId, string signCode) {
            var hashStr = _zxjcRecordProvider.GetHashStr(detailId);
            var hashData = RsaCryption.GetHash(hashStr);
            if (RsaCryption.ValidateSignature(publicKey, hashData, signCode.Replace("_", "/"))) {
                var result = _zxjcRecordProvider.GetZxjcTaskModel(detailId);
                return this.Success(result);
            }
            else
                return new ApiResultModel<SaveZxjcDetailModel>();
        }