P3P Header Info in MVC

Question

I'm not sure where I'm suppose to put this in my Asp.net MVC website:

HttpContext.Current.Response.AppendHeader("P3P", "CP=\\\"IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT\\\"");

I put it in the:

public static void RegisterRoutes(RouteCollection routes)
{
  HttpContext.Current.Response.AppendHeader("P3P", "CP=\\\"IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT\\\"");
  routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
  routes.MapRoute(
      "Default", // Route name
      "{controller}/{action}/{id}", // URL with parameters
      new { controller = "Account", action = "Logon", id = UrlParameter.Optional }
  );

}

But I get back

Response is not available in this context.

Anyone know where I am suppose to put this?

score 38 · Accepted Answer · edited May 23 '17 at 10:30

38

You can put it in the web.config:

  <system.webServer>
    <httpProtocol>
      <customHeaders>
        <add name="P3P" value='CP="CAO PSA OUR"'/>

This way you do not need to put it in the code.

See this SO answer for details on what the value means.

edited May 23 '17 at 10:30

Community

1
1

answered Dec 20 '12 at 15:52

vtortola

34,709
29
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1

Thanks a lot. You saved me from an eternity of pointless debugging. – Chorinator Sep 11 '13 at 00:03
1

@vtortola: Thanks! This was driving me crazy. Great solution. – richb01 Apr 13 '14 at 17:20
P3P header is not supported by any modern browser in 2020 (https://en.wikipedia.org/wiki/P3P) – Jithin Pavithran Apr 26 '20 at 08:45

score 9 · Answer 2 · answered Dec 20 '12 at 15:55

Assuming you want this header on every response, something like this should do it

public class P3PHeaderAttribute : ActionFilterAttribute
{
    public override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        filterContext.HttpContext.Response.AppendHeader("P3P", "CP=\\\"IDC DSP COR ADM DEVi TAIi PSA PSD IVAi IVDi CONi HIS OUR IND CNT\\\"");

    }
}

then add the filter to the global collection

    public static void RegisterGlobalFilters(GlobalFilterCollection filters)
    {
        filters.Add(new P3PHeaderAttribute());
    }

this is what I was looking for but I already used the web.config change. I upvoted you, thank you! — ErocM, Dec 20 '12 at 16:07

score 1 · Answer 3 · answered Dec 20 '12 at 15:51

1

You should create a class that inherits ActionFilter and overrides OnResultExecuting() to add that header.

Then, add it to the global filters collection.

answered Dec 20 '12 at 15:51

SLaks

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P3P Header Info in MVC

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