/// <summary>
/// 限制访问校验
/// </summary>
async Task LimitValidAsync(VisitorContext visitor)
{
Options.WriteRecord?.Invoke(visitor);
visitor.Judgement = Options.ReadRecord(visitor);
foreach (var strategy in Options.AccessStrategies)
{
var effected = strategy.Attempt(visitor);
if (effected)
{
break;
}
}
}
/// <summary>
/// 黑名单校验
/// </summary>
/// <returns></returns>
public bool Attempt(VisitorContext context)
{
if (context.Judgement == null)
{
return(false);
}
if (context.Judgement.ContainedInBlack == null)
{
return(false);
}
if (context.Judgement.ContainedInBlack())
{
return(context.ChangeResult(true, LimitLevel.All));
}
return(false);
}
/// <summary>
/// 中间件执行
/// </summary>
/// <param name="context">请求上下文</param>
/// <returns></returns>
public override async Task Invoke(IOwinContext context)
{
var token = Global.CookieProvider.GetRequestCookie(context, Options.VisitorTokenKey);
var Visitor = new VisitorContext(context, Global.WebSite, token);
if (Visitor.IsStatices())
{
await Next.Invoke(context);
return;
}
await LimitValidAsync(Visitor);
await InvokeAsync(context, Visitor);
}
/// <summary>
/// 执行
/// </summary>
/// <returns></returns>
public bool Attempt(VisitorContext context)
{
if (context.Judgement == null)
{
return(false);
}
if (context.Judgement.GradeInMonitoring == null)
{
return(false);
}
var grade = context.Judgement.GradeInMonitoring();
if (grade > 0)
{
return(context.ChangeResult(true, LimitLevel.Limit));
}
return(false);
}
/// <summary>
/// 限制请求处理
/// </summary>
async Task InvokeAsync(IOwinContext context, VisitorContext visitor)
{
switch (visitor.Result)
{
case LimitLevel.All:; context.Response.StatusCode = 403; return;
case LimitLevel.None: await Next.Invoke(context); return;
}
if (string.IsNullOrEmpty(Options.LimitAddress))
{
context.Response.StatusCode = 404;
// await Next.Invoke(context);
return;
}
var url = $"{Options.LimitAddress}?ul={Global.WebSite}{visitor.Link}";
context.Response.Redirect(url);
}
/// <summary>
/// 排除预期结果
/// </summary>
public bool Attempt(VisitorContext context)
{
// 只监测 Get 方法
if (context.Method.Contains("GET") == false)
{
return(true);
}
if (context.Judgement == null)
{
return(false);
}
if (context.Judgement.ContainedInExcluded == null)
{
return(false);
}
if (context.Judgement.ContainedInExcluded())
{
return(context.ChangeResult(true, LimitLevel.None));
}
return(false);
}
