/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*

 * Content policy implementation that prevents all loads of images,

 * subframes, etc from protocols that don't return data but rather open

 * applications (such as mailto).

 */

#include "nsNoDataProtocolContentPolicy.h"

#include "nsIDOMWindow.h"

#include "nsString.h"

#include "nsIProtocolHandler.h"

#include "nsIIOService.h"

#include "nsIExternalProtocolHandler.h"

#include "nsIURI.h"

#include "nsNetUtil.h"

#include "nsContentUtils.h"

NS_IMPL_ISUPPORTS(nsNoDataProtocolContentPolicy, nsIContentPolicy)

NS_IMETHODIMP

nsNoDataProtocolContentPolicy::ShouldLoad(nsIURI *aContentLocation,

                                          nsILoadInfo *aLoadInfo,

                                          const nsACString &aMimeGuess,

                                          int16_t *aDecision)

{

  uint32_t contentType = aLoadInfo->GetExternalContentPolicyType();

  MOZ_ASSERT(contentType == nsContentUtils::InternalContentPolicyTypeToExternal(contentType),

             "We should only see external content policy types here.");

  *aDecision = nsIContentPolicy::ACCEPT;

  // Don't block for TYPE_OBJECT since such URIs are sometimes loaded by the

  // plugin, so they don't necessarily open external apps

  // TYPE_WEBSOCKET loads can only go to ws:// or wss://, so we don't need to

  // concern ourselves with them.

  if (contentType != TYPE_DOCUMENT &&

      contentType != TYPE_SUBDOCUMENT &&

      contentType != TYPE_OBJECT &&

      contentType != TYPE_WEBSOCKET) {

    // The following are just quick-escapes for the most common cases

    // where we would allow the content to be loaded anyway.

    nsAutoCString scheme;

    aContentLocation->GetScheme(scheme);

    if (scheme.EqualsLiteral("http") ||

        scheme.EqualsLiteral("https") ||

        scheme.EqualsLiteral("ftp") ||

        scheme.EqualsLiteral("file") ||

        scheme.EqualsLiteral("chrome")) {

      return NS_OK;

    }

    bool shouldBlock;

    nsresult rv = NS_URIChainHasFlags(aContentLocation,

                                      nsIProtocolHandler::URI_DOES_NOT_RETURN_DATA,

                                      &shouldBlock);

    if (NS_SUCCEEDED(rv) && shouldBlock) {

      *aDecision = nsIContentPolicy::REJECT_REQUEST;

    }

  }

  return NS_OK;

}

NS_IMETHODIMP

nsNoDataProtocolContentPolicy::ShouldProcess(nsIURI *aContentLocation,

                                             nsILoadInfo* aLoadInfo,

                                             const nsACString &aMimeGuess,

                                             int16_t *aDecision)

{

  return ShouldLoad(aContentLocation, aLoadInfo, aMimeGuess, aDecision);

}