大家都知道在应用中，有时我们需要对访问的客户端进行有效性验证，只有提供有效凭证（AccessToken）的终端应用能访问我们的受控站点（如WebAPI站点），此时我们可以通过验证属性的方法来解决。
本文将详细介绍ASP.NET Core使用自定义验证属性控制访问权限的相关内容，分享出来供大家参考学习，下面话不多说了，来一起看看详细的介绍吧
方法如下
一、public class Startup的配置：
//启用跨域访问（不同端口也是跨域） services.AddCors(options => { options.AddPolicy("AllowOriginOtherBis", builder => builder.WithOrigins("https://1.16.9.12:4432", "https://pc12.ato.biz:4432", "https://localhost:44384", "https://1.16.9.12:4432", "https://pc12.ato.biz:4432").AllowAnyMethod().AllowAnyHeader()); }); //启用自定义属性以便对控制器或Action进行[TerminalApp()]定义。 services.AddSingleton<IAuthorizationHandler, TerminalAppAuthorizationHandler>(); services.AddAuthorization(options => { options.AddPolicy("TerminalApp", policyBuilder => { policyBuilder.Requirements.Add(new TerminalAppAuthorizationRequirement()); }); });
二、public void Configure(IApplicationBuilder app, IHostingEnvironment env)中的配置：
app.UseHttpsRedirection(); //使用Https传输 app.UseCors("AllowOriginOtherBis"); //根据定义启用跨域设置
三、示例WebApi项目结构：
四、主要代码（我采用的从数据库进行验证）：
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)] internal class TerminalAppAttribute : AuthorizeAttribute { public string AppID { get; } /// <summary> /// 指定客户端访问API /// </summary> /// <param></param> public TerminalAppAttribute(string appID="") : base("TerminalApp") { AppID = appID; } }
public abstract class AttributeAuthorizationHandler<TRequirement, TAttribute> : AuthorizationHandler<TRequirement> where TRequirement : IAuthorizationRequirement where TAttribute : Attribute { protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement) { var attributes = new List<TAttribute>(); if ((context.Resource as AuthorizationFilterContext)?.ActionDescriptor is ControllerActionDescriptor action) { attributes.AddRange(GetAttributes(action.ControllerTypeInfo.UnderlyingSystemType)); attributes.AddRange(GetAttributes(action.MethodInfo)); } return HandleRequirementAsync(context, requirement, attributes); } protected abstract Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement, IEnumerable<TAttribute> attributes); private static IEnumerable<TAttribute> GetAttributes(MemberInfo memberInfo) { return memberInfo.GetCustomAttributes(typeof(TAttribute), false).Cast<TAttribute>(); } } internal class TerminalAppAuthorizationHandler : AttributeAuthorizationHandler<TerminalAppAuthorizationRequirement,TerminalAppAttribute> { protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, TerminalAppAuthorizationRequirement requirement, IEnumerable<TerminalAppAttribute> attributes) { object errorMsg = string.Empty; //如果取不到身份验证信息，并且不允许匿名访问，则返回未验证403 if (context.Resource is AuthorizationFilterContext filterContext && filterContext.ActionDescriptor is ControllerActionDescriptor descriptor) { //先判断是否是匿名访问, if (descriptor != null) { var actionAttributes = descriptor.MethodInfo.GetCustomAttributes(inherit: true); bool isAnonymous = actionAttributes.Any(a => a is AllowAnonymousAttribute); //非匿名的方法,链接中添加accesstoken值 if (isAnonymous) { context.Succeed(requirement); return Task.CompletedTask; } else { //url获取access_token //从AuthorizationHandlerContext转成HttpContext，以便取出表求信息 var httpContext = (context.Resource as AuthorizationFilterContext).HttpContext; //var questUrl = httpContext.Request.Path.Value.ToLower(); string requestAppID = httpContext.Request.Headers["appid"]; string requestAccessToken = httpContext.Request.Headers["access_token"]; if ((!string.IsNullOrEmpty(requestAppID)) && (!string.IsNullOrEmpty(requestAccessToken))) { if (attributes != null) { //当不指定具体的客户端AppID仅运用验证属性时默认所有客户端都接受 if (attributes.ToArray().ToString()=="") { //任意一个在数据库列表中的App都可以运行,否则先判断提交的APPID与需要ID是否相符 bool mat = false; foreach (var terminalAppAttribute in attributes) { if (terminalAppAttribute.AppID == requestAppID) { mat = true; break; } } if (!mat) { errorMsg = ReturnStd.NotAuthorize("客户端应用未在服务端登记或未被授权运用当前功能."); return HandleBlockedAsync(context, requirement, errorMsg); } } } //如果未指定attributes，则表示任何一个终端服务都可以调用服务, 在验证区域验证终端提供的ID是否匹配数据库记录 string valRst = ValidateToken(requestAppID, requestAccessToken); if (string.IsNullOrEmpty(valRst)) { context.Succeed(requirement); return Task.CompletedTask; } else { errorMsg = ReturnStd.NotAuthorize("AccessToken验证失败(" + valRst + ")","91"); return HandleBlockedAsync(context, requirement, errorMsg); } } else { errorMsg = ReturnStd.NotAuthorize("未提供AppID或Token."); return HandleBlockedAsync(context, requirement, errorMsg); //return Task.CompletedTask; } } } } else { errorMsg = ReturnStd.NotAuthorize("FilterContext类型不匹配."); return HandleBlockedAsync(context, requirement, errorMsg); } errorMsg = ReturnStd.NotAuthorize("未知错误."); return HandleBlockedAsync(context,requirement, errorMsg); } //校验票据（数据库数据匹配） /// <summary> /// 验证终端服务程序提供的AccessToken是否合法 /// </summary> /// <param>终端APP的ID</param> /// <param>终端APP利用其自身AppKEY运算出来的AccessToken,与服务器生成的进行比对</param> /// <returns></returns> private string ValidateToken(string appID,string accessToken) { try { DBContextMain dBContext = new DBContextMain(); string appKeyOnServer = string.Empty; //从数据库读取AppID对应的KEY(此KEY为加解密算法的AES_KEY AuthApp authApp = dBContext.AuthApps.FirstOrDefault(a => a.AppID == appID); if (authApp == null) { return "客户端应用没有在云端登记!"; } else { appKeyOnServer = authApp.APPKey; } if (string.IsNullOrEmpty(appKeyOnServer)) { return "客户端应用基础信息有误!"; } string tmpToken = string.Empty; tmpToken = System.Net.WebUtility.UrlDecode(accessToken);//解码相应的Token到原始字符(因其中可能会有+=等特殊字符,必须编码后传递) tmpToken = OCrypto.AES16Decrypt(tmpToken, appKeyOnServer); //使用APPKEY解密并分析 if (string.IsNullOrEmpty(tmpToken)) { return "客户端提交的身份令牌运算为空!"; } else { try { //原始验证码为im_cloud_sv001-appid-ticks格式 //取出时间,与服务器时间对比,超过10秒即拒绝服务 long tmpTime =Convert.ToInt64(tmpToken.Substring(tmpToken.LastIndexOf("-")+1)); //DateTime dt = DateTime.ParseExact(tmpTime, "yyyyMMddHHmmss", CultureInfo.CurrentCulture); DateTime dt= new DateTime(tmpTime); bool IsInTimeSpan = (Convert.ToDouble(ODateTime.DateDiffSeconds(dt, DateTime.Now)) <= 7200); bool IsInternalApp = (tmpToken.IndexOf("im_cloud_sv001-") >= 0); if (!IsInternalApp || !IsInTimeSpan) { return "令牌未被许可或已经失效!"; } else { return string.Empty; //成功验证 } } catch (Exception ex) { return "令牌解析出错(" + ex.Message + ")"; } } } catch (Exception ex) { return "令牌解析出错(" + ex.Message + ")"; } } private Task HandleBlockedAsync(AuthorizationHandlerContext context, TerminalAppAuthorizationRequirement requirement, object errorMsg) { var authorizationFilterContext = context.Resource as AuthorizationFilterContext; authorizationFilterContext.Result = new JsonResult(errorMsg) { StatusCode = 202 }; //设置为403会显示不了自定义信息,改为Accepted202,由客户端处理 context.Succeed(requirement); return Task.CompletedTask; } }
internal class TerminalAppAuthorizationRequirement : IAuthorizationRequirement { public TerminalAppAuthorizationRequirement() { } }
五、相应的Token验证代码：