PlzNavigate: Move navigation-level mixed content checks to the browser.

content/browser/frame_host/mixed_content_navigation_throttle.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/frame_host/mixed_content_navigation_throttle.h"
+
+#include "base/memory/ptr_util.h"
+#include "base/stl_util.h"
+#include "content/browser/frame_host/frame_tree.h"
+#include "content/browser/frame_host/frame_tree_node.h"
+#include "content/browser/frame_host/navigation_handle_impl.h"
+#include "content/browser/frame_host/render_frame_host_delegate.h"
+#include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/common/frame_messages.h"
+#include "content/public/browser/content_browser_client.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/common/browser_side_navigation_policy.h"
+#include "content/public/common/content_client.h"
+#include "content/public/common/origin_util.h"
+#include "content/public/common/web_preferences.h"
+#include "net/base/url_util.h"
+#include "url/gurl.h"
+#include "url/origin.h"
+#include "url/url_constants.h"
+#include "url/url_util.h"
+
+namespace {
+
+using namespace content;
+
+// Should return the same value as SchemeRegistry::shouldTreatURLSchemeAsSecure.
+bool IsSecureScheme(const std::string& scheme) {
+  return base::ContainsValue(url::GetSecureSchemes(), scheme);
+}
+
+// Should return the same value as SecurityOrigin::isLocal and
+// SchemeRegistry::shouldTreatURLSchemeAsCORSEnabled.
+bool ShouldTreatURLSchemeAsCORSEnabled(const GURL& url) {
+  return base::ContainsValue(url::GetCORSEnabledSchemes(), url.scheme());
+}
+
+// Should return the same value as SecurityOrigin::isSecure.
+// TODO(carlosk): secure origin checks don't match between content and Blink
+// hence this implementation here instead of a direct call to IsOriginSecure (in
+// origin_util.cc). See https://crbug.com/629059.
+bool IsOriginSecure(const GURL& url) {
+  if (IsSecureScheme(url.scheme()))
+    return true;
+
+  if (url.SchemeIsFileSystem() || url.SchemeIsBlob()) {
+    // Should use inner URL.
+    url::Origin origin(url);
+    if (IsSecureScheme(origin.scheme()))
+      return true;
+  }
+
+  return IsOriginWhiteListedTrustworthy(url::Origin(url));
+}
+
+// Should return the same value as the resource URL checks assigned to
+// |isAllowed| made inside MixedContentChecker::isMixedContent.
+bool IsUrlPotentiallySecure(const GURL& url) {
+  // blob: and filesystem: URLs never hit the network, and access is restricted
+  // to same-origin contexts, so they are not blocked.
+  bool is_secure =
+      url.SchemeIs(url::kBlobScheme) || url.SchemeIs(url::kFileSystemScheme) ||
+      IsOriginSecure(url) || IsPotentiallyTrustworthyOrigin(url::Origin(url));
+
+  // TODO(mkwst): Remove this once the following draft is implemented:
+  // https://tools.ietf.org/html/draft-west-let-localhost-be-localhost-03. See:
+  // https://crbug.com/691930.
+  if (is_secure && url.SchemeIs(url::kHttpScheme) &&
+      net::IsLocalHostname(url.HostNoBrackets(), nullptr)) {
+    is_secure = false;
+  }
+
+  return is_secure;
+}
+
+// This method should return the same results as
+// SchemeRegistry::shouldTreatURLSchemeAsRestrictingMixedContent.
+bool DoesOriginSchemeRestrictsMixedContent(const url::Origin& origin) {

[nasko, 2017/02/15 17:41:39]

minor nit: Does takes off the 's' suffix from verbs, so
DoesOriginSchemeRestrict(no s)MixedContent.

[carlosk, 2017/02/15 21:46:31]

Done.

+  return origin.scheme() == url::kHttpsScheme;
+}
+
+void UpdateRendererOnMixedContentFound(NavigationHandleImpl* navigation_handle,
+                                       const GURL& mixed_content_url,
+                                       bool was_allowed,
+                                       bool for_redirect) {
+  // TODO(carlosk): the root node should never be considered as being/having
+  // mixed content for now. Once/if the browser should also check form submits
+  // for mixed content than this will be allowed to happen and this DCHECK
+  // should be updated.
+  DCHECK(navigation_handle->frame_tree_node()->parent());
+  RenderFrameHost* rfh =
+      navigation_handle->frame_tree_node()->current_frame_host();
+  rfh->Send(new FrameMsg_MixedContentFound(
+      rfh->GetRoutingID(), mixed_content_url, navigation_handle->GetURL(),
+      navigation_handle->request_context_type(), was_allowed, for_redirect));
+}
+
+}  // namespace
+
+namespace content {
+
+// static
+std::unique_ptr<NavigationThrottle>
+MixedContentNavigationThrottle::CreateThrottleForNavigation(
+    NavigationHandle* navigation_handle) {
+  if (IsBrowserSideNavigationEnabled())
+    return base::WrapUnique(
+        new MixedContentNavigationThrottle(navigation_handle));
+  return nullptr;
+}
+
+MixedContentNavigationThrottle::MixedContentNavigationThrottle(
+    NavigationHandle* navigation_handle)
+    : NavigationThrottle(navigation_handle) {
+  DCHECK(IsBrowserSideNavigationEnabled());
+}
+
+MixedContentNavigationThrottle::~MixedContentNavigationThrottle() {}
+
+ThrottleCheckResult MixedContentNavigationThrottle::WillStartRequest() {
+  bool should_block = ShouldBlockNavigation(false);
+  return should_block ? ThrottleCheckResult::CANCEL
+                      : ThrottleCheckResult::PROCEED;
+}
+
+ThrottleCheckResult MixedContentNavigationThrottle::WillRedirectRequest() {
+  // Upon redirects the same checks are to be executed as for requests.
+  bool should_block = ShouldBlockNavigation(true);
+  return should_block ? ThrottleCheckResult::CANCEL
+                      : ThrottleCheckResult::PROCEED;
+}
+
+ThrottleCheckResult MixedContentNavigationThrottle::WillProcessResponse() {
+  // TODO(carlosk): At this point we are about to process the request response.
+  // So if we ever need to, here/now it is a good moment to check for the final
+  // attained security level of the connection. For instance, does it use an
+  // outdated protocol? The implementation should be based off
+  // MixedContentChecker::handleCertificateError. See https://crbug.com/576270.
+  return ThrottleCheckResult::PROCEED;
+}
+
+// Based off of MixedContentChecker::shouldBlockFetch.
+bool MixedContentNavigationThrottle::ShouldBlockNavigation(bool for_redirect) {
+  NavigationHandleImpl* handle_impl =
+      static_cast<NavigationHandleImpl*>(navigation_handle());
+  FrameTreeNode* node = handle_impl->frame_tree_node();
+
+  // Find the parent node where mixed content is characterized, if any.
+  FrameTreeNode* mixed_content_node =
+      InWhichFrameIsContentMixed(node, handle_impl->GetURL());
+  if (!mixed_content_node) {
+    MaybeSendBlinkFeatureUsageReport();
+    return false;
+  }
+
+  // From this point on we know this is not a main frame navigation and that
+  // there is mixed content. Now let's decide if it's OK to proceed with it.
+  const WebPreferences& prefs = mixed_content_node->current_frame_host()
+                                    ->render_view_host()
+                                    ->GetWebkitPreferences();
+
+  ReportBasicMixedContentFeatures(handle_impl->request_context_type(),
+                                  handle_impl->mixed_content_context_type(),
+                                  prefs);
+
+  // If we're in strict mode, we'll automagically fail everything, and
+  // intentionally skip the client/embedder checks in order to prevent degrading
+  // the site's security UI.
+  bool block_all_mixed_content = !!(
+      mixed_content_node->current_replication_state().insecure_request_policy &
+      blink::kBlockAllMixedContent);
+  bool strict_mode =
+      prefs.strict_mixed_content_checking || block_all_mixed_content;
+
+  blink::WebMixedContentContextType mixed_context_type =
+      handle_impl->mixed_content_context_type();
+
+  if (!ShouldTreatURLSchemeAsCORSEnabled(handle_impl->GetURL()))
+    mixed_context_type = blink::WebMixedContentContextType::OptionallyBlockable;
+
+  bool allowed = false;
+  RenderFrameHostDelegate* frame_host_delegate =
+      node->current_frame_host()->delegate();
+  switch (mixed_context_type) {
+    case blink::WebMixedContentContextType::OptionallyBlockable:
+      allowed = !strict_mode;
+      if (allowed) {
+        frame_host_delegate->PassiveInsecureContentFound(handle_impl->GetURL());
+        frame_host_delegate->DidDisplayInsecureContent();
+      }
+      break;
+
+    case blink::WebMixedContentContextType::Blockable: {
+      // Note: from the renderer side implementation it seems like we don't need
+      // to care about reporting
+      // blink::UseCounter::BlockableMixedContentInSubframeBlocked because it is
+      // only triggered for sub-resources which are not checked for in the
+      // browser.
+      bool should_ask_delegate =
+          !strict_mode && (!prefs.strictly_block_blockable_mixed_content ||
+                           prefs.allow_running_insecure_content);
+      allowed =
+          should_ask_delegate &&
+          frame_host_delegate->ShouldAllowRunningInsecureContent(
+              handle_impl->GetWebContents(),
+              prefs.allow_running_insecure_content,
+              mixed_content_node->current_origin(), handle_impl->GetURL());
+      if (allowed) {
+        const GURL& origin_url = mixed_content_node->current_origin().GetURL();
+        frame_host_delegate->DidRunInsecureContent(origin_url,
+                                                   handle_impl->GetURL());
+        GetContentClient()->browser()->RecordURLMetric(
+            "ContentSettings.MixedScript.RanMixedScript", origin_url);
+        mixed_content_features_.insert(MIXED_CONTENT_BLOCKABLE_ALLOWED);
+      }
+      break;
+    }
+
+    case blink::WebMixedContentContextType::ShouldBeBlockable:
+      allowed = !strict_mode;
+      if (allowed)
+        frame_host_delegate->DidDisplayInsecureContent();
+      break;
+
+    case blink::WebMixedContentContextType::NotMixedContent:
+      NOTREACHED();
+      break;
+  };
+
+  UpdateRendererOnMixedContentFound(
+      handle_impl, mixed_content_node->current_url(), allowed, for_redirect);
+  MaybeSendBlinkFeatureUsageReport();
+
+  return !allowed;
+}
+
+// This method mirrors MixedContentChecker::inWhichFrameIsContentMixed but is
+// implemented in a different form that seems more appropriate here.
+FrameTreeNode* MixedContentNavigationThrottle::InWhichFrameIsContentMixed(
+    FrameTreeNode* node,
+    const GURL& url) {
+  // Main frame navigations cannot be mixed content.
+  // TODO(carlosk): except for form submissions which might be supported in the
+  // future.
+  if (node->IsMainFrame())
+    return nullptr;
+
+  // There's no mixed content if any of these are true:
+  // - The navigated URL is potentially secure.
+  // - Neither the root nor parent frames have secure origins.
+  // This next section diverges in how the Blink version is implemented but
+  // should get to the same results. Especially where isMixedContent calls
+  // exist, here they are partially fulfilled here  and partially replaced by
+  // DoesOriginSchemeRestrictsMixedContent.
+  FrameTreeNode* mixed_content_node = nullptr;
+  FrameTreeNode* root = node->frame_tree()->root();
+  FrameTreeNode* parent = node->parent();
+  if (!IsUrlPotentiallySecure(url)) {
+    // TODO(carlosk): we might need to check more than just the immediate parent
+    // and the root. See https://crbug.com/623486.
+
+    // Checks if the root and then the immediate parent frames' origins are
+    // secure.
+    if (DoesOriginSchemeRestrictsMixedContent(root->current_origin()))
+      mixed_content_node = root;
+    else if (DoesOriginSchemeRestrictsMixedContent(parent->current_origin()))
+      mixed_content_node = parent;
+  }
+
+  // Note: The code below should behave the same way as the two calls to
+  // measureStricterVersionOfIsMixedContent from inside
+  // MixedContentChecker::inWhichFrameIs.
+  if (mixed_content_node) {
+    // We're currently only checking for mixed content in `https://*` contexts.
+    // What about other "secure" contexts the SchemeRegistry knows about? We'll
+    // use this method to measure the occurrence of non-webby mixed content to
+    // make sure we're not breaking the world without realizing it.
+    if (mixed_content_node->current_origin().scheme() != url::kHttpsScheme) {
+      mixed_content_features_.insert(
+          MIXED_CONTENT_IN_NON_HTTPS_FRAME_THAT_RESTRICTS_MIXED_CONTENT);
+    }
+  } else if (!IsOriginSecure(url) &&
+             (IsSecureScheme(root->current_origin().scheme()) ||
+              IsSecureScheme(parent->current_origin().scheme()))) {
+    mixed_content_features_.insert(
+        MIXED_CONTENT_IN_SECURE_FRAME_THAT_DOES_NOT_RESTRICT_MIXED_CONTENT);
+  }
+  return mixed_content_node;
+}
+
+void MixedContentNavigationThrottle::MaybeSendBlinkFeatureUsageReport() {
+  if (!mixed_content_features_.empty()) {
+    NavigationHandleImpl* handle_impl =
+        static_cast<NavigationHandleImpl*>(navigation_handle());
+    RenderFrameHost* rfh = handle_impl->frame_tree_node()->current_frame_host();
+    rfh->Send(new FrameMsg_BlinkFeatureUsageReport(rfh->GetRoutingID(),
+                                                   mixed_content_features_));
+    mixed_content_features_.clear();
+  }
+}
+
+// Based off of MixedContentChecker::count.
+void MixedContentNavigationThrottle::ReportBasicMixedContentFeatures(
+    RequestContextType request_context_type,
+    blink::WebMixedContentContextType mixed_content_context_type,
+    const WebPreferences& prefs) {
+  mixed_content_features_.insert(MIXED_CONTENT_PRESENT);
+
+  // Report any blockable content.
+  if (mixed_content_context_type ==
+      blink::WebMixedContentContextType::Blockable) {
+    mixed_content_features_.insert(MIXED_CONTENT_BLOCKABLE);
+    return;
+  }
+
+  // Note: as there's no mixed content checks for sub-resources on the browser
+  // side there should only be a subset of RequestContextType values that could
+  // ever be found here.
+  UseCounterFeature feature;
+  switch (request_context_type) {
+    case REQUEST_CONTEXT_TYPE_INTERNAL:
+      feature = MIXED_CONTENT_INTERNAL;
+      break;
+    case REQUEST_CONTEXT_TYPE_PREFETCH:
+      feature = MIXED_CONTENT_PREFETCH;
+      break;
+
+    case REQUEST_CONTEXT_TYPE_AUDIO:
+    case REQUEST_CONTEXT_TYPE_DOWNLOAD:
+    case REQUEST_CONTEXT_TYPE_FAVICON:
+    case REQUEST_CONTEXT_TYPE_IMAGE:
+    case REQUEST_CONTEXT_TYPE_PLUGIN:
+    case REQUEST_CONTEXT_TYPE_VIDEO:
+    default:
+      NOTREACHED() << "RequestContextType has value " << request_context_type
+                   << " and has WebMixedContentContextType of "
+                   << static_cast<int>(mixed_content_context_type);
+      return;
+  }
+  mixed_content_features_.insert(feature);
+}
+
+// static
+bool MixedContentNavigationThrottle::IsMixedContentForTesting(
+    const GURL& origin_url,
+    const GURL& url) {
+  const url::Origin origin(origin_url);
+  return !IsUrlPotentiallySecure(url) &&
+         DoesOriginSchemeRestrictsMixedContent(origin);
+}
+
+}  // namespace content