原文地址：WebApi 使用TOKEN+签名验证
一、不进行验证的方式
api查询接口：
客户端调用：http://api.XXX.com/getproduct?id=value1
如上，这种方式简单粗暴，在浏览器直接输入"http://api.XXX.com/getproduct?id=value1"，即可获取产品列表信息了，但是这样的方式会存在很严重的安全性问题，没有进行任何的验证，大家都可以通过这个方法获取到产品列表，导致产品信息泄露。
那么，如何验证调用者身份呢？如何防止参数被篡改呢？如何保证请求的唯一性？ 如何保证请求的唯一性，防止请求被恶意攻击呢？
二、使用TOKEN+签名认证 保证请求安全性
token+签名认证的主要原理是：1.做一个认证服务，提供一个认证的webapi，用户先访问它获取对应的token
2.用户拿着相应的token以及请求的参数和服务器端提供的签名算法计算出签名后再去访问指定的api
3.服务器端每次接收到请求就获取对应用户的token和请求参数，服务器端再次计算签名和客户端签名做对比，如果验证通过则正常访问相应的api，验证失败则返回具体的失败信息
具体代码如下 ：
1.用户请求认证服务GetToken，将TOKEN保存在服务器端缓存中，并返回对应的TOKEN到客户端（该请求不需要进行签名认证）
public HttpResponseMessage GetToken(string staffId)
{
ResultMsg resultMsg = null;
int id = 0;
//判断参数是否合法
if (string.IsNullOrEmpty(staffId) || (!int.TryParse(staffId, out id)))
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.ParameterError;
resultMsg.Info = StatusCodeEnum.ParameterError.GetEnumText();
resultMsg.Data = "";
return HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
}
//插入缓存
Token token =(Token)HttpRuntime.Cache.Get(id.ToString());
if (HttpRuntime.Cache.Get(id.ToString()) == null)
{
token = new Token();
token.StaffId = id;
token.SignToken = Guid.NewGuid();
token.ExpireTime = DateTime.Now.AddDays(1);
HttpRuntime.Cache.Insert(token.StaffId.ToString(), token, null, token.ExpireTime, TimeSpan.Zero);
}
//返回token信息
resultMsg =new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.Success;
resultMsg.Info = "";
resultMsg.Data = token;
return HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
}
2.客户端调用服务器端API，需要对请求进行签名认证，签名方式如下
（1） get请求：按照请求参数名称将所有请求参数按照字母先后顺序排序得到：keyvaluekeyvalue...keyvalue 字符串如：将arong=1,mrong=2,crong=3 排序为：arong=1, crong=3,mrong=2 然后将参数名和参数值进行拼接得到参数字符串：arong1crong3mrong2。
public static Tuple<string,string> GetQueryString(Dictionary<string, string> parames)post请求：将请求的参数对象序列化为json格式字符串
{
// 第一步：把字典按Key的字母顺序排序
IDictionary<string, string> sortedParams = new SortedDictionary<string, string>(parames);
IEnumerator<KeyValuePair<string, string>> dem = sortedParams.GetEnumerator();
// 第二步：把所有参数名和参数值串在一起
StringBuilder query = new StringBuilder(""); //签名字符串
StringBuilder queryStr = new StringBuilder(""); //url参数
if (parames == null || parames.Count == 0)
return new Tuple<string,string>("","");
while (dem.MoveNext())
{
string key = dem.Current.Key;
string value = dem.Current.Value;
if (!string.IsNullOrEmpty(key))
{
query.Append(key).Append(value);
queryStr.Append("&").Append(key).Append("=").Append(value);
}
}
return new Tuple<string, string>(query.ToString(), queryStr.ToString().Substring(1, queryStr.Length - 1));
}
Product product = new Product() { Id = 1, Name = "安慕希", Count = 10, Price = 58.8 };
var data=JsonConvert.SerializeObject(product);
（2）在请求头中添加timespan（时间戳），nonce（随机数），staffId（用户Id），signature（签名参数）
//加入头信息(3)根据请求参数计算本次请求的签名，用timespan+nonc+staffId+token+data（请求参数字符串）得到signStr签名字符串，然后再进行排序和MD5加密得到最终的signature签名字符串，添加到请求头中
request.Headers.Add("staffid", staffId.ToString()); //当前请求用户StaffId
request.Headers.Add("timestamp", timeStamp); //发起请求时的时间戳（单位：毫秒）
request.Headers.Add("nonce", nonce); //发起请求时的时间戳（单位：毫秒）
request.Headers.Add("signature", GetSignature(timeStamp,nonce,staffId,data)); //当前请求内容的数字签名
private static string GetSignature(string timeStamp,string nonce,int staffId,string data)
{
Token token = null;
var resultMsg = GetSignToken(staffId);
if (resultMsg != null)
{
if (resultMsg.StatusCode == (int)StatusCodeEnum.Success)
{
token = resultMsg.Result;
}
else
{
throw new Exception(resultMsg.Data.ToString());
}
}
else
{
throw new Exception("token为null，员工编号为：" +staffId);
}
var hash = System.Security.Cryptography.MD5.Create();
//拼接签名数据
var signStr = timeStamp +nonce+ staffId + token.SignToken.ToString() + data;
//将字符串中字符按升序排序
var sortStr = string.Concat(signStr.OrderBy(c => c));
var bytes = Encoding.UTF8.GetBytes(sortStr);
//使用MD5加密
var md5Val = hash.ComputeHash(bytes);
//把二进制转化为大写的十六进制
StringBuilder result = new StringBuilder();
foreach (var c in md5Val)
{
result.Append(c.ToString("X2"));
}
return result.ToString().ToUpper();
}
（4） webapi接收到相应的请求，取出请求头中的timespan，nonc，staffid，signature 数据，根据timespan判断此次请求是否失效，根据staffid取出相应token判断token是否失效，根据请求类型取出对应的请求参数，然后服务器端按照同样的规则重新计算请求签名，判断和请求头中的signature数据是否相同，如果相同的话则是合法请求，正常返回数据，如果不相同的话，该请求可能被恶意篡改，禁止访问相应的数据，返回相应的错误信息
如下使用全局过滤器拦截所有api请求进行统一的处理
public class ApiSecurityFilter : ActionFilterAttribute
{
public override void OnActionExecuting(System.Web.Http.Controllers.HttpActionContext actionContext)
{
ResultMsg resultMsg = null;
var request = actionContext.Request;
string method = request.Method.Method;
string staffid = String.Empty, timestamp = string.Empty, nonce = string.Empty, signature = string.Empty;
int id = 0;
if (request.Headers.Contains("staffid"))
{
staffid = HttpUtility.UrlDecode(request.Headers.GetValues("staffid").FirstOrDefault());
}
if (request.Headers.Contains("timestamp"))
{
timestamp = HttpUtility.UrlDecode(request.Headers.GetValues("timestamp").FirstOrDefault());
}
if (request.Headers.Contains("nonce"))
{
nonce = HttpUtility.UrlDecode(request.Headers.GetValues("nonce").FirstOrDefault());
}
if (request.Headers.Contains("signature"))
{
signature = HttpUtility.UrlDecode(request.Headers.GetValues("signature").FirstOrDefault());
}
//GetToken方法不需要进行签名验证
if (actionContext.ActionDescriptor.ActionName == "GetToken")
{
if (string.IsNullOrEmpty(staffid) || (!int.TryParse(staffid, out id) || string.IsNullOrEmpty(timestamp) || string.IsNullOrEmpty(nonce)))
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.ParameterError;
resultMsg.Info = StatusCodeEnum.ParameterError.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
else
{
base.OnActionExecuting(actionContext);
return;
}
}
//判断请求头是否包含以下参数
if (string.IsNullOrEmpty(staffid) || (!int.TryParse(staffid, out id) || string.IsNullOrEmpty(timestamp) || string.IsNullOrEmpty(nonce) || string.IsNullOrEmpty(signature)))
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.ParameterError;
resultMsg.Info = StatusCodeEnum.ParameterError.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
//判断timespan是否有效
double ts1 = 0;
double ts2 = (DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0)).TotalMilliseconds;
bool timespanvalidate = double.TryParse(timestamp, out ts1);
double ts = ts2 - ts1;
bool falg = ts > int.Parse(WebSettingsConfig.UrlExpireTime) * 1000;
if (falg || (!timespanvalidate))
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.URLExpireError;
resultMsg.Info = StatusCodeEnum.URLExpireError.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
//判断token是否有效
Token token = (Token)HttpRuntime.Cache.Get(id.ToString());
string signtoken = string.Empty;
if (HttpRuntime.Cache.Get(id.ToString()) == null)
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.TokenInvalid;
resultMsg.Info = StatusCodeEnum.TokenInvalid.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
else
{
signtoken = token.SignToken.ToString();
}
//根据请求类型拼接参数
NameValueCollection form = HttpContext.Current.Request.QueryString;
string data = string.Empty;
switch (method)
{
case "POST":
Stream stream = HttpContext.Current.Request.InputStream;
string responseJson = string.Empty;
StreamReader streamReader = new StreamReader(stream);
data = streamReader.ReadToEnd();
break;
case "GET":
//第一步：取出所有get参数
IDictionary<string, string> parameters = new Dictionary<string, string>();
for (int f = 0; f < form.Count; f++)
{
string key = form.Keys[f];
parameters.Add(key, form[key]);
}
// 第二步：把字典按Key的字母顺序排序
IDictionary<string, string> sortedParams = new SortedDictionary<string, string>(parameters);
IEnumerator<KeyValuePair<string, string>> dem = sortedParams.GetEnumerator();
// 第三步：把所有参数名和参数值串在一起
StringBuilder query = new StringBuilder();
while (dem.MoveNext())
{
string key = dem.Current.Key;
string value = dem.Current.Value;
if (!string.IsNullOrEmpty(key))
{
query.Append(key).Append(value);
}
}
data = query.ToString();
break;
default:
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.HttpMehtodError;
resultMsg.Info = StatusCodeEnum.HttpMehtodError.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
bool result = SignExtension.Validate(timestamp, nonce, id, signtoken,data, signature);
if (!result)
{
resultMsg = new ResultMsg();
resultMsg.StatusCode = (int)StatusCodeEnum.HttpRequestError;
resultMsg.Info = StatusCodeEnum.HttpRequestError.GetEnumText();
resultMsg.Data = "";
actionContext.Response = HttpResponseExtension.toJson(JsonConvert.SerializeObject(resultMsg));
base.OnActionExecuting(actionContext);
return;
}
else
{
base.OnActionExecuting(actionContext);
}
}
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
base.OnActionExecuted(actionExecutedContext);
}
}
详细地址：http://www.cnblogs.com/MR-YY/p/5972380.html#!comments