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content / browser / preloading / prerender / prerender_host.cc [blame]
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/preloading/prerender/prerender_host.h"
#include <memory>
#include <optional>
#include "base/debug/alias.h"
#include "base/feature_list.h"
#include "base/notreached.h"
#include "base/observer_list.h"
#include "base/run_loop.h"
#include "base/task/thread_pool.h"
#include "base/time/time.h"
#include "base/trace_event/typed_macros.h"
#include "content/browser/client_hints/client_hints.h"
#include "content/browser/devtools/devtools_instrumentation.h"
#include "content/browser/preloading/prefetch/no_vary_search_helper.h"
#include "content/browser/preloading/preloading_attempt_impl.h"
#include "content/browser/preloading/preloading_trigger_type_impl.h"
#include "content/browser/preloading/prerender/devtools_prerender_attempt.h"
#include "content/browser/preloading/prerender/prerender_features.h"
#include "content/browser/preloading/prerender/prerender_final_status.h"
#include "content/browser/preloading/prerender/prerender_host_registry.h"
#include "content/browser/preloading/prerender/prerender_metrics.h"
#include "content/browser/renderer_host/frame_tree.h"
#include "content/browser/renderer_host/frame_tree_node.h"
#include "content/browser/renderer_host/navigation_controller_impl.h"
#include "content/browser/renderer_host/navigation_entry_restore_context_impl.h"
#include "content/browser/renderer_host/navigation_request.h"
#include "content/browser/renderer_host/render_frame_host_impl.h"
#include "content/browser/web_contents/web_contents_impl.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/navigation_controller.h"
#include "content/public/browser/preloading_trigger_type.h"
#include "content/public/browser/web_contents_delegate.h"
#include "content/public/common/referrer.h"
#include "net/base/load_flags.h"
#include "net/http/http_request_headers.h"
#include "third_party/blink/public/common/client_hints/enabled_client_hints.h"
#include "third_party/blink/public/common/features.h"
#include "url/origin.h"
namespace content {
namespace {
base::OnceCallback<void(FrameTreeNodeId)>& GetHostCreationCallbackForTesting() {
static base::NoDestructor<base::OnceCallback<void(FrameTreeNodeId)>>
host_creation_callback_for_testing;
return *host_creation_callback_for_testing;
}
} // namespace
// static
PrerenderHost* PrerenderHost::GetFromFrameTreeNodeIfPrerendering(
FrameTreeNode& frame_tree_node) {
if (!frame_tree_node.frame_tree().is_prerendering()) {
return nullptr;
}
return &GetFromFrameTreeNode(frame_tree_node);
}
// static
PrerenderHost& PrerenderHost::GetFromFrameTreeNode(
FrameTreeNode& frame_tree_node) {
CHECK(frame_tree_node.frame_tree().is_prerendering());
return *static_cast<PrerenderHost*>(frame_tree_node.frame_tree().delegate());
}
// static
bool PrerenderHost::AreHttpRequestHeadersCompatible(
const std::string& potential_activation_headers_str,
const std::string& prerender_headers_str,
PreloadingTriggerType trigger_type,
const std::string& histogram_suffix,
PrerenderCancellationReason& reason) {
net::HttpRequestHeaders prerender_headers;
prerender_headers.AddHeadersFromString(prerender_headers_str);
net::HttpRequestHeaders potential_activation_headers;
potential_activation_headers.AddHeadersFromString(
potential_activation_headers_str);
// `prerender_headers` contains the "Purpose: prefetch" and "Sec-Purpose:
// prefetch;prerender" to notify servers of prerender requests, while
// `potential_activation_headers` doesn't contain it. Remove "Purpose" and
// "Sec-Purpose" matching from consideration so that activation works with the
// header.
prerender_headers.RemoveHeader("Purpose");
potential_activation_headers.RemoveHeader("Purpose");
prerender_headers.RemoveHeader("Sec-Purpose");
potential_activation_headers.RemoveHeader("Sec-Purpose");
prerender_headers.RemoveHeader("RTT");
potential_activation_headers.RemoveHeader("RTT");
prerender_headers.RemoveHeader("Downlink");
potential_activation_headers.RemoveHeader("Downlink");
// TODO(crbug.com/40244149): Instead of handling headers added by
// embedders specifically, prerender should expose an interface to embedders
// to set url parameters.
#if BUILDFLAG(IS_ANDROID)
// Used by Android devices only.
if (trigger_type == PreloadingTriggerType::kEmbedder) {
prerender_headers.RemoveHeader("X-Geo");
potential_activation_headers.RemoveHeader("X-Geo");
}
#endif // BUILDFLAG(IS_ANDROID)
// Remove the viewport headers as the viewport size of the initiator page can
// be changed during prerendering. See also https://crbug.com/1401244.
prerender_headers.RemoveHeader("viewport-width");
potential_activation_headers.RemoveHeader("viewport-width");
prerender_headers.RemoveHeader("sec-ch-viewport-width");
potential_activation_headers.RemoveHeader("sec-ch-viewport-width");
// Don't need to handle "viewport-height" as it is not defined in the specs.
prerender_headers.RemoveHeader("sec-ch-viewport-height");
potential_activation_headers.RemoveHeader("sec-ch-viewport-height");
return PrerenderHost::IsActivationHeaderMatch(potential_activation_headers,
prerender_headers, reason);
}
// static
void PrerenderHost::SetHostCreationCallbackForTesting(
base::OnceCallback<void(FrameTreeNodeId host_id)> callback) {
GetHostCreationCallbackForTesting() = std::move(callback); // IN-TEST
}
PrerenderHost::PrerenderHost(
const PrerenderAttributes& attributes,
WebContentsImpl& web_contents,
base::WeakPtr<PreloadingAttempt> attempt,
std::unique_ptr<DevToolsPrerenderAttempt> devtools_attempt)
: attributes_(attributes),
metric_suffix_(
GeneratePrerenderHistogramSuffix(trigger_type(),
embedder_histogram_suffix())),
attempt_(std::move(attempt)),
devtools_attempt_(std::move(devtools_attempt)),
web_contents_(web_contents),
frame_tree_(std::make_unique<FrameTree>(web_contents.GetBrowserContext(),
this,
this,
&web_contents,
&web_contents,
&web_contents,
&web_contents,
&web_contents,
&web_contents,
FrameTree::Type::kPrerender)) {
// If the prerendering is browser-initiated, it is expected to have no
// initiator. All initiator related information should be null or invalid. On
// the other hand, renderer-initiated prerendering should have valid initiator
// information.
if (attributes.IsBrowserInitiated()) {
CHECK(!attributes.initiator_origin.has_value());
CHECK(!attributes.initiator_frame_token.has_value());
CHECK_EQ(attributes.initiator_process_id,
ChildProcessHost::kInvalidUniqueID);
CHECK_EQ(attributes.initiator_ukm_id, ukm::kInvalidSourceId);
CHECK(attributes.initiator_frame_tree_node_id.is_null());
} else {
CHECK(attributes.initiator_origin.has_value());
CHECK(attributes.initiator_frame_token.has_value());
CHECK_NE(attributes.initiator_process_id,
ChildProcessHost::kInvalidUniqueID);
CHECK_NE(attributes.initiator_ukm_id, ukm::kInvalidSourceId);
CHECK(attributes.initiator_frame_tree_node_id);
}
SetTriggeringOutcome(PreloadingTriggeringOutcome::kTriggeredButPending);
scoped_refptr<SiteInstanceImpl> site_instance =
SiteInstanceImpl::Create(web_contents.GetBrowserContext());
frame_tree_->Init(site_instance.get(),
/*renderer_initiated_creation=*/false,
/*main_frame_name=*/"", /*opener_for_origin=*/nullptr,
/*frame_policy=*/blink::FramePolicy(),
base::UnguessableToken::Create());
// Use the same SessionStorageNamespace as the primary page for the
// prerendering page.
frame_tree_->controller().SetSessionStorageNamespace(
site_instance->GetStoragePartitionConfig(),
web_contents_->GetPrimaryFrameTree()
.controller()
.GetSessionStorageNamespace(
site_instance->GetStoragePartitionConfig()));
// TODO(crbug.com/40177940): This should be moved to FrameTree::Init
web_contents_->NotifySwappedFromRenderManager(
/*old_frame=*/nullptr,
frame_tree_->root()->render_manager()->current_frame_host());
frame_tree_node_id_ = frame_tree_->root()->frame_tree_node_id();
if (GetHostCreationCallbackForTesting()) {
std::move(GetHostCreationCallbackForTesting()) // IN-TEST
.Run(frame_tree_node_id_);
}
}
// static
bool PrerenderHost::IsActivationHeaderMatch(
const net::HttpRequestHeaders& potential_activation_headers,
const net::HttpRequestHeaders& prerender_headers,
PrerenderCancellationReason& reason) {
// Normalize the headers.
using HeaderPair = net::HttpRequestHeaders::HeaderKeyValuePair;
auto cmp = [](const HeaderPair& a, const HeaderPair& b) {
return a.key < b.key;
};
auto lower_case = [](HeaderPair& x) { x.key = base::ToLowerASCII(x.key); };
auto same_predicate = [](const HeaderPair& a, const HeaderPair& b) {
return a.key == b.key && base::EqualsCaseInsensitiveASCII(a.value, b.value);
};
std::vector<HeaderPair> potential_header_list(
potential_activation_headers.GetHeaderVector());
std::vector<HeaderPair> prerender_header_list(
prerender_headers.GetHeaderVector());
std::for_each(potential_header_list.begin(), potential_header_list.end(),
lower_case);
std::for_each(prerender_header_list.begin(), prerender_header_list.end(),
lower_case);
std::sort(potential_header_list.begin(), potential_header_list.end(), cmp);
std::sort(prerender_header_list.begin(), prerender_header_list.end(), cmp);
std::unique_ptr<std::vector<PrerenderMismatchedHeaders>> mismatched_headers =
std::make_unique<std::vector<PrerenderMismatchedHeaders>>();
auto prerender_header_list_it = prerender_header_list.begin();
auto potential_header_list_it = potential_header_list.begin();
while (prerender_header_list_it != prerender_header_list.end() &&
potential_header_list_it != potential_header_list.end()) {
if (same_predicate(*prerender_header_list_it, *potential_header_list_it)) {
prerender_header_list_it++;
potential_header_list_it++;
} else if (prerender_header_list_it->key == potential_header_list_it->key) {
mismatched_headers->emplace_back(prerender_header_list_it->key,
prerender_header_list_it->value,
potential_header_list_it->value);
prerender_header_list_it++;
potential_header_list_it++;
} else if (prerender_header_list_it->key < potential_header_list_it->key) {
mismatched_headers->emplace_back(prerender_header_list_it->key,
prerender_header_list_it->value,
std::nullopt);
prerender_header_list_it++;
} else {
mismatched_headers->emplace_back(potential_header_list_it->key,
std::nullopt,
potential_header_list_it->value);
potential_header_list_it++;
}
}
while (prerender_header_list_it != prerender_header_list.end()) {
mismatched_headers->emplace_back(prerender_header_list_it->key,
prerender_header_list_it->value,
std::nullopt);
prerender_header_list_it++;
}
while (potential_header_list_it != potential_header_list.end()) {
mismatched_headers->emplace_back(potential_header_list_it->key,
std::nullopt,
potential_header_list_it->value);
potential_header_list_it++;
}
if (mismatched_headers->empty()) {
return true;
}
reason.SetPrerenderMismatchedHeaders(std::move(mismatched_headers));
return false;
}
PrerenderHost::~PrerenderHost() {
for (auto& observer : observers_) {
observer.OnHostDestroyed(
final_status_.value_or(PrerenderFinalStatus::kDestroyed));
}
if (!final_status_) {
RecordFailedFinalStatusImpl(
PrerenderCancellationReason(PrerenderFinalStatus::kDestroyed));
}
// If we are still waiting on test loop, we can assume the page loading step
// has been cancelled and the PrerenderHost is being discarded without
// completing loading the page.
if (on_wait_loading_finished_) {
std::move(on_wait_loading_finished_)
.Run(PrerenderHost::LoadingOutcome::kPrerenderingCancelled);
}
if (frame_tree_) {
frame_tree_->Shutdown();
}
}
void PrerenderHost::DidStopLoading() {
if (on_wait_loading_finished_) {
std::move(on_wait_loading_finished_).Run(LoadingOutcome::kLoadingCompleted);
}
}
bool PrerenderHost::IsHidden() {
return true;
}
FrameTree* PrerenderHost::LoadingTree() {
// For prerendering loading tree is the same as its frame tree as loading is
// done at a frame tree level in the background, unlike the loading visible
// to the user where we account for nested frame tree loading state.
return frame_tree_.get();
}
void PrerenderHost::SetFocusedFrame(FrameTreeNode* node,
SiteInstanceGroup* source) {
// `node` can only become focused when `node`'s current RenderFrameHost is
// active.
NOTREACHED();
}
FrameTree* PrerenderHost::GetOwnedPictureInPictureFrameTree() {
return nullptr;
}
FrameTree* PrerenderHost::GetPictureInPictureOpenerFrameTree() {
return nullptr;
}
FrameTreeNodeId PrerenderHost::GetOuterDelegateFrameTreeNodeId() {
// A prerendered FrameTree is not "inner to" or "nested inside" another
// FrameTree; it exists in parallel to the primary FrameTree of the current
// WebContents. Therefore, it must not attempt to access the primary
// FrameTree in the sense of an "outer delegate" relationship, so we return
// the invalid ID here.
return FrameTreeNodeId();
}
RenderFrameHostImpl* PrerenderHost::GetProspectiveOuterDocument() {
// A prerendered FrameTree never has an outer document.
return nullptr;
}
void PrerenderHost::ActivateAndShowRepostFormWarningDialog() {
// Not supported, cancel pending reload.
GetNavigationController().CancelPendingReload();
}
bool PrerenderHost::ShouldPreserveAbortedURLs() {
return false;
}
// TODO(crbug.com/40150744): Inspect diffs from the current
// no-state-prefetch implementation. See PrerenderContents::StartPrerendering()
// for example.
bool PrerenderHost::StartPrerendering() {
TRACE_EVENT0("navigation", "PrerenderHost::StartPrerendering");
// Since prerender started we mark it as eligible and set it to running.
SetTriggeringOutcome(PreloadingTriggeringOutcome::kRunning);
// Start prerendering navigation.
NavigationController::LoadURLParams load_url_params(
attributes_.prerendering_url);
load_url_params.initiator_origin = attributes_.initiator_origin;
load_url_params.initiator_process_id = attributes_.initiator_process_id;
load_url_params.initiator_frame_token = attributes_.initiator_frame_token;
load_url_params.is_renderer_initiated = !attributes_.IsBrowserInitiated();
load_url_params.transition_type =
ui::PageTransitionFromInt(attributes_.transition_type);
// Just use the referrer from attributes, as NoStatePrefetch does.
load_url_params.referrer = attributes_.referrer;
load_url_params.override_user_agent =
web_contents_->GetDelegate()->ShouldOverrideUserAgentForPrerender2();
// TODO(https://crbug.com/1406149, https://crbug.com/1378921): Set
// `override_user_agent` for Android. This field is determined on the Java
// side based on the URL and we should mimic Java code and set it to the
// correct value. After fixing this, we can remove the check for UA headers
// upon activation.
// TODO(crbug.com/40150744): Set up other fields of `load_url_params`
// as well, and add tests for them.
base::WeakPtr<NavigationHandle> created_navigation_handle =
GetNavigationController().LoadURLWithParams(load_url_params);
if (!created_navigation_handle)
return false;
if (attributes_.prerender_navigation_handle_callback) {
attributes_.prerender_navigation_handle_callback.Run(
*created_navigation_handle);
}
// Even when LoadURLWithParams() returns a valid navigation handle, navigation
// can fail during navigation start, for example, due to prerendering a
// non-supported URL scheme that is filtered out in
// PrerenderNavigationThrottle.
if (final_status_.has_value())
return false;
if (initial_navigation_id_.has_value()) {
// In usual code path, `initial_navigation_id_` should be set by
// PrerenderNavigationThrottle during `LoadURLWithParams` above.
CHECK_EQ(*initial_navigation_id_,
created_navigation_handle->GetNavigationId());
CHECK(begin_params_);
CHECK(common_params_);
} else {
// In some exceptional code path, such as the navigation failed due to CSP
// violations, PrerenderNavigationThrottle didn't run at this point. So,
// set the ID here.
initial_navigation_id_ = created_navigation_handle->GetNavigationId();
// `begin_params_` and `common_params_` is null here, but it doesn't matter
// as this branch is reached only when the initial navigation fails,
// so this PrerenderHost can't be activated.
// Original code assumes the case CSP prefetch-src blocks prerendering, but
// prefetch-src was already deprecated, but this code path seems still
// reachable. To be clarify the actual scenario, let's have the dump code.
// We may eventually return false for this code path to make things simple.
// TODO(crbug.com/40248615): Monitor reports and decide if we
// continue to have the `is_ready_for_activation_` check in
// CheckInitialPrerenderNavigationParamsCompatibleWithNavigation().
net::Error net_error = created_navigation_handle->GetNetErrorCode();
base::debug::Alias(&net_error);
base::debug::DumpWithoutCrashing();
}
NavigationRequest* navigation_request =
NavigationRequest::From(created_navigation_handle.get());
// The initial navigation in the prerender frame tree should not wait for
// `beforeunload` in the old page, so BeginNavigation stage should be reached
// synchronously.
CHECK_GE(navigation_request->state(),
NavigationRequest::WAITING_FOR_RENDERER_RESPONSE);
return true;
}
void PrerenderHost::DidStartNavigation(NavigationHandle* navigation_handle) {
CHECK(base::FeatureList::IsEnabled(
blink::features::kPrerender2MainFrameNavigation));
auto* navigation_request = NavigationRequest::From(navigation_handle);
CHECK(navigation_request->IsInPrerenderedMainFrame());
// Do nothing for the initial navigation.
if (IsInitialNavigation(*navigation_request)) {
return;
}
// Reset `is_ready_for_activation_` since it can be set to true more than once
// and CHECK will fail when the main frame navigation happens in a
// prerendered page and PrerenderHost::DidFinishNavigation is called multiple
// times.
is_ready_for_activation_ = false;
}
void PrerenderHost::ReadyToCommitNavigation(
NavigationHandle* navigation_handle) {
CHECK(navigation_handle);
// For the initial navigation, set No-Vary-Search if there is a
// No-Vary-Search header.
auto* navigation_request = NavigationRequest::From(navigation_handle);
CHECK(navigation_request->IsInPrerenderedMainFrame());
// Prerender frame tree node is alive, see:
// `PrerenderHostRegistry::ReadyToCommitNavigation`.
CHECK(frame_tree_);
CHECK_EQ(frame_tree_.get(),
&navigation_request->frame_tree_node()->frame_tree());
if (!IsInitialNavigation(*navigation_request)) {
return;
}
if (base::FeatureList::IsEnabled(blink::features::kPrerender2NoVarySearch) &&
navigation_request->response() &&
navigation_request->response()->parsed_headers &&
navigation_request->response()
->parsed_headers->no_vary_search_with_parse_error) {
MaybeSetNoVarySearch(
*navigation_request->response()
->parsed_headers->no_vary_search_with_parse_error);
} else {
CHECK(!no_vary_search_.has_value());
CHECK(!no_vary_search_parse_error_.has_value());
}
// ReadyToCommitNavigation is called when the headers are received.
were_headers_received_ = true;
for (auto& observer : observers_) {
observer.OnHeadersReceived();
}
}
void PrerenderHost::DidFinishNavigation(NavigationHandle* navigation_handle) {
auto* navigation_request = NavigationRequest::From(navigation_handle);
// Observe navigation only in the prerendering frame tree.
CHECK_EQ(&(navigation_request->frame_tree_node()->frame_tree()),
frame_tree_.get());
const bool is_prerender_main_frame =
navigation_request->GetFrameTreeNodeId() == frame_tree_node_id_;
// Cancel prerendering on navigation request failure.
//
// Check net::Error here rather than PrerenderNavigationThrottle as CSP
// blocking occurs before NavigationThrottles so cannot be observed in
// NavigationThrottle::WillFailRequest().
net::Error net_error = navigation_request->GetNetErrorCode();
std::optional<PrerenderFinalStatus> status;
if (net_error == net::Error::ERR_BLOCKED_BY_CSP) {
status = PrerenderFinalStatus::kNavigationRequestBlockedByCsp;
} else if (net_error == net::Error::ERR_BLOCKED_BY_CLIENT) {
status = PrerenderFinalStatus::kBlockedByClient;
} else if (is_prerender_main_frame && net_error != net::Error::OK) {
status = PrerenderFinalStatus::kNavigationRequestNetworkError;
} else if (is_prerender_main_frame && !navigation_request->HasCommitted()) {
status = PrerenderFinalStatus::kNavigationNotCommitted;
}
if (status.has_value()) {
Cancel(*status);
return;
}
// The prerendered contents are considered ready for activation when the
// main frame navigation reaches DidFinishNavigation and the prerender host
// has not been canceled yet.
if (is_prerender_main_frame && !final_status_) {
CHECK(!is_ready_for_activation_);
is_ready_for_activation_ = true;
// Prerender is ready to activate. Set the status to kReady.
SetTriggeringOutcome(PreloadingTriggeringOutcome::kReady);
}
}
std::unique_ptr<StoredPage> PrerenderHost::Activate(
NavigationRequest& navigation_request) {
TRACE_EVENT1("navigation", "PrerenderHost::Activate", "navigation_request",
&navigation_request);
CHECK(is_ready_for_activation_);
is_ready_for_activation_ = false;
FrameTree& target_frame_tree = web_contents_->GetPrimaryFrameTree();
// There should be no ongoing main-frame navigation during activation.
// TODO(crbug.com/40174232): Make sure sub-frame navigations are
// fine.
CHECK(!frame_tree_->root()->HasNavigation());
// Before the root's current_frame_host is cleared, collect the subframes of
// `frame_tree_` whose FrameTree will need to be updated.
FrameTree::NodeRange node_range = frame_tree_->Nodes();
std::vector<FrameTreeNode*> subframe_nodes(std::next(node_range.begin()),
node_range.end());
// Before the root's current_frame_host is cleared, collect the replication
// state so that it can be used for post-activation validation.
blink::mojom::FrameReplicationState prior_replication_state =
frame_tree_->root()->current_replication_state();
// Update FrameReplicationState::has_received_user_gesture_before_nav of the
// prerendered page.
//
// On regular navigation, it is updated via a renderer => browser IPC
// (RenderFrameHostImpl::HadStickyUserActivationBeforeNavigationChanged),
// which is sent from blink::DocumentLoader::CommitNavigation. However,
// this doesn't happen on prerender page activation, so the value is not
// correctly updated without this treatment.
//
// The updated value will be sent to the renderer on
// blink::mojom::Page::ActivatePrerenderedPage.
prior_replication_state.has_received_user_gesture_before_nav =
navigation_request.frame_tree_node()
->has_received_user_gesture_before_nav();
// frame_tree_->root(). Do not add any code between here and
// frame_tree_.reset() that calls into observer functions to minimize the
// duration of current_frame_host being null.
std::unique_ptr<StoredPage> page =
frame_tree_->root()->render_manager()->TakePrerenderedPage();
NavigationEntryRestoreContextImpl context;
std::unique_ptr<NavigationEntryImpl> nav_entry =
GetNavigationController()
.GetEntryWithUniqueID(page->render_frame_host()->nav_entry_id())
->CloneWithoutSharing(&context);
navigation_request.SetPrerenderActivationNavigationState(
std::move(nav_entry), prior_replication_state);
CHECK_EQ(&target_frame_tree,
&navigation_request.frame_tree_node()->frame_tree());
// We support activating the prerendered page only to the topmost
// RenderFrameHost.
CHECK(!page->render_frame_host()->GetParentOrOuterDocumentOrEmbedder());
page->render_frame_host()->SetFrameTreeNode(*(target_frame_tree.root()));
page->render_frame_host()->SetRenderFrameHostOwner(target_frame_tree.root());
// Copy frame name into the replication state of the primary main frame to
// ensure that the replication state of the primary main frame after
// activation matches the replication state stored in the renderer.
// TODO(crbug.com/40192974): Copying frame name here is suboptimal
// and ideally we'd do this at the same time when transferring the proxies
// from the StoredPage into RenderFrameHostManager. However, this is a
// temporary solution until we move this into BrowsingContextState,
// along with RenderFrameProxyHost.
page->render_frame_host()->frame_tree_node()->set_frame_name_for_activation(
prior_replication_state.unique_name, prior_replication_state.name);
for (auto& it : page->proxy_hosts()) {
it.second->set_frame_tree_node(*(target_frame_tree.root()));
}
// Iterate over the root RenderFrameHost's subframes and update the
// associated frame tree. Note that subframe proxies don't need their
// FrameTrees independently updated, since their FrameTreeNodes don't
// change, and FrameTree references in those FrameTreeNodes will be updated
// through RenderFrameHosts.
//
// TODO(crbug.com/40177949): Need to investigate if and how
// pending delete RenderFrameHost objects should be handled if prerendering
// runs all of the unload handlers; they are not currently handled here.
// This is because pending delete RenderFrameHosts can still receive and
// process some messages while the RenderFrameHost FrameTree and
// FrameTreeNode are stale.
for (FrameTreeNode* subframe_node : subframe_nodes) {
subframe_node->SetFrameTree(target_frame_tree);
}
frame_tree_->Shutdown();
frame_tree_.reset();
page->render_frame_host()->ForEachRenderFrameHostIncludingSpeculative(
[this](RenderFrameHostImpl* rfh) {
// The visibility state of the prerendering page has not been
// updated by
// WebContentsImpl::UpdateVisibilityAndNotifyPageAndView(). So
// updates the visibility state using the PageVisibilityState of
// `web_contents`.
rfh->render_view_host()->SetFrameTreeVisibility(
web_contents_->GetPageVisibilityState());
});
for (auto& observer : observers_)
observer.OnActivated();
// The activated page is on the primary tree now. It can propagate the client
// hints to the global settings.
BrowserContext* browser_context =
target_frame_tree.controller().GetBrowserContext();
ClientHintsControllerDelegate* client_hints_delegate =
browser_context->GetClientHintsControllerDelegate();
if (client_hints_delegate) {
for (auto& [origin, client_hint] : client_hints_type_) {
PersistAcceptCH(origin, *(target_frame_tree.root()),
client_hints_delegate, client_hint);
}
}
RecordActivation(navigation_request);
// Prerender is activated. Set the status to kSuccess.
SetTriggeringOutcome(PreloadingTriggeringOutcome::kSuccess);
devtools_instrumentation::DidActivatePrerender(
navigation_request, initiator_devtools_navigation_token());
return page;
}
// Ensure that the frame policies are compatible between primary main frame and
// prerendering main frame:
// a) primary main frame's pending_frame_policy would normally apply to the new
// document during its creation. However, for prerendering we can't apply it as
// the document is already created.
// b) prerender main frame's pending_frame_policy can't be transferred to the
// primary main frame, we should not activate if it's non-zero.
// c) Existing document can't change the frame_policy it is affected by, so we
// can't transfer RenderFrameHosts between FrameTreeNodes with different frame
// policies.
//
// Usually frame policy for the main frame is empty as in the most common case a
// parent document sets a policy on the child iframe.
bool PrerenderHost::IsFramePolicyCompatibleWithPrimaryFrameTree() {
FrameTreeNode* prerender_root_ftn = frame_tree_->root();
FrameTreeNode* primary_root_ftn = web_contents_->GetPrimaryFrameTree().root();
// Ensure that the pending frame policy is not set on the main frames, as it
// is usually set on frames by their parent frames.
if (prerender_root_ftn->pending_frame_policy() != blink::FramePolicy()) {
return false;
}
if (primary_root_ftn->pending_frame_policy() != blink::FramePolicy()) {
return false;
}
if (prerender_root_ftn->current_replication_state().frame_policy !=
primary_root_ftn->current_replication_state().frame_policy) {
return false;
}
return true;
}
bool PrerenderHost::AreInitialPrerenderNavigationParamsCompatibleWithNavigation(
NavigationRequest& navigation_request,
PrerenderCancellationReason& reason) {
// TODO(crbug.com/40170513): compare the rest of the navigation parameters. We
// should introduce compile-time parameter checks as well, to ensure how new
// fields should be compared for compatibility.
// As the initial prerender navigation is a) limited to HTTP(s) URLs and b)
// initiated by the PrerenderHost, we do not expect some navigation parameters
// connected to certain navigation types to be set and the CHECKS below
// enforce that.
// The parameters of the potential activation, however, are coming from the
// renderer and we mostly don't have any guarantees what they are, so we
// should not CHECK them. Instead, by default we compare them with initial
// prerender activation parameters and fail to activate when they differ.
// Note: some of those parameters should be never set (or should be ignored)
// for main-frame / HTTP(s) navigations, but we still compare them here as a
// defence-in-depth measure.
CHECK(navigation_request.IsInPrimaryMainFrame());
// Check `common_params_` and `begin_params_` here as these can be nullptr
// if LoadURLWithParams failed without running PrerenderNavigationThrottle.
if (!common_params_ || !begin_params_) {
return false;
}
// Relaxes checks for initiator and transition type. This logic is intended to
// be used for WebView, as WebView is intended to host embedder-trusted
// contests.
bool allow_initiator_and_transition_mismatch =
web_contents_->GetDelegate()->ShouldAllowPartialParamMismatchOfPrerender2(
navigation_request);
// Compare BeginNavigationParams.
ActivationNavigationParamsMatch result =
AreBeginNavigationParamsCompatibleWithNavigation(
navigation_request.begin_params(),
allow_initiator_and_transition_mismatch, reason);
if (result != ActivationNavigationParamsMatch::kOk) {
RecordPrerenderActivationNavigationParamsMatch(result,
GetHistogramSuffix());
return false;
}
// Compare CommonNavigationParams.
result = AreCommonNavigationParamsCompatibleWithNavigation(
navigation_request.common_params(),
allow_initiator_and_transition_mismatch);
if (result != ActivationNavigationParamsMatch::kOk) {
RecordPrerenderActivationNavigationParamsMatch(result,
GetHistogramSuffix());
return false;
}
RecordPrerenderActivationNavigationParamsMatch(
ActivationNavigationParamsMatch::kOk, GetHistogramSuffix());
return true;
}
PrerenderHost::ActivationNavigationParamsMatch
PrerenderHost::AreBeginNavigationParamsCompatibleWithNavigation(
const blink::mojom::BeginNavigationParams& potential_activation,
bool allow_initiator_and_transition_mismatch,
PrerenderCancellationReason& reason) {
CHECK(begin_params_);
// TODO(https://crbug.com/340416082): Check details of security properties,
// update the check to appropriate form and remove differences among all
// platforms.
if (!allow_initiator_and_transition_mismatch &&
(potential_activation.initiator_frame_token !=
begin_params_->initiator_frame_token)) {
return ActivationNavigationParamsMatch::kInitiatorFrameToken;
}
if (!AreHttpRequestHeadersCompatible(potential_activation.headers,
begin_params_->headers, trigger_type(),
GetHistogramSuffix(), reason)) {
return ActivationNavigationParamsMatch::kHttpRequestHeader;
}
// Don't activate a prerendered page if the potential activation request
// requires validation or bypass of the browser cache, as the prerendered page
// is a kind of caches.
// TODO(crbug.com/40183588): Instead of checking the load flags on
// activation, we should cancel prerendering when the prerender initial
// navigation has the flags.
int cache_load_flags = net::LOAD_VALIDATE_CACHE | net::LOAD_BYPASS_CACHE |
net::LOAD_DISABLE_CACHE;
if (potential_activation.load_flags & cache_load_flags) {
return ActivationNavigationParamsMatch::kCacheLoadFlags;
}
if (potential_activation.load_flags != begin_params_->load_flags) {
return ActivationNavigationParamsMatch::kLoadFlags;
}
if (potential_activation.skip_service_worker !=
begin_params_->skip_service_worker) {
return ActivationNavigationParamsMatch::kSkipServiceWorker;
}
if (potential_activation.mixed_content_context_type !=
begin_params_->mixed_content_context_type) {
return ActivationNavigationParamsMatch::kMixedContentContextType;
}
// Initial prerender navigation cannot be a form submission.
CHECK(!begin_params_->is_form_submission);
if (potential_activation.is_form_submission !=
begin_params_->is_form_submission) {
return ActivationNavigationParamsMatch::kIsFormSubmission;
}
if (potential_activation.searchable_form_url !=
begin_params_->searchable_form_url) {
return ActivationNavigationParamsMatch::kSearchableFormUrl;
}
if (potential_activation.searchable_form_encoding !=
begin_params_->searchable_form_encoding) {
return ActivationNavigationParamsMatch::kSearchableFormEncoding;
}
// Trust token params can be set only on subframe navigations, so both values
// should be null here.
CHECK(!begin_params_->trust_token_params);
if (potential_activation.trust_token_params !=
begin_params_->trust_token_params) {
return ActivationNavigationParamsMatch::kTrustTokenParams;
}
// Don't require equality for request_context_type because link clicks
// (HYPERLINK) should be allowed for activation, whereas prerender always has
// type LOCATION.
CHECK_EQ(begin_params_->request_context_type,
blink::mojom::RequestContextType::LOCATION);
switch (potential_activation.request_context_type) {
case blink::mojom::RequestContextType::HYPERLINK:
case blink::mojom::RequestContextType::LOCATION:
break;
default:
return ActivationNavigationParamsMatch::kRequestContextType;
}
// Since impression should not be set, no need to compare contents.
CHECK(!begin_params_->impression);
if (potential_activation.impression.has_value()) {
return ActivationNavigationParamsMatch::kImpressionHasValue;
}
// No need to test for devtools_initiator because this field is used for
// tracking what triggered a network request, and prerender activation will
// not use network requests.
return ActivationNavigationParamsMatch::kOk;
}
PrerenderHost::ActivationNavigationParamsMatch
PrerenderHost::AreCommonNavigationParamsCompatibleWithNavigation(
const blink::mojom::CommonNavigationParams& potential_activation,
bool allow_initiator_and_transition_mismatch) {
// The CommonNavigationParams::url field is expected to match both initial and
// activation prerender navigations, as the PrerenderHost selection would have
// already checked for matching values. Adding a CHECK here to be safe.
CHECK(common_params_);
if (attributes_.url_match_predicate) {
// TODO(crbug.com/41494389): Figure out what we need to pass here as a
// web_url_match result instead of std::nullopt.
CHECK(attributes_.url_match_predicate.Run(potential_activation.url,
std::nullopt));
} else if (no_vary_search_.has_value()) {
CHECK(no_vary_search_->AreEquivalent(potential_activation.url,
common_params_->url));
} else if (no_vary_search_expected().has_value()) {
CHECK(no_vary_search_expected()->AreEquivalent(potential_activation.url,
common_params_->url));
} else {
CHECK_EQ(potential_activation.url, common_params_->url);
}
// TODO(https://crbug.com/340416082): Check details of security properties,
// update the check to appropriate form and remove differences among all
// platforms.
if (!allow_initiator_and_transition_mismatch &&
(potential_activation.initiator_origin !=
common_params_->initiator_origin)) {
return ActivationNavigationParamsMatch::kInitiatorOrigin;
}
// The transition must match with the exception of the client redirect flag.
// The renderer may add the client redirect flag when it has enough
// information to be certain that this navigation would replace the current
// history entry (e.g., a renderer-initiated navigation to the current URL).
int32_t potential_activation_transition =
potential_activation.transition & ~ui::PAGE_TRANSITION_CLIENT_REDIRECT;
if (!allow_initiator_and_transition_mismatch &&
(potential_activation_transition != common_params_->transition)) {
RecordPrerenderActivationTransition(potential_activation_transition,
GetHistogramSuffix());
return ActivationNavigationParamsMatch::kTransition;
}
CHECK_EQ(common_params_->navigation_type,
blink::mojom::NavigationType::DIFFERENT_DOCUMENT);
if (potential_activation.navigation_type != common_params_->navigation_type) {
return ActivationNavigationParamsMatch::kNavigationType;
}
// We don't check download_policy as it affects whether the download triggered
// by the NavigationRequest is allowed to proceed (or logs metrics) and
// doesn't affect the behaviour of the document created by a non-download
// navigation after commit (e.g. it doesn't affect future downloads in child
// frames). PrerenderNavigationThrottle has already ensured that the initial
// prerendering navigation isn't a download and as prerendering activation
// won't reach out to the network, it won't turn into a navigation as well.
CHECK(common_params_->base_url_for_data_url.is_empty());
if (potential_activation.base_url_for_data_url !=
common_params_->base_url_for_data_url) {
return ActivationNavigationParamsMatch::kBaseUrlForDataUrl;
}
// The method parameter is compared only by CHECK_EQ because that change is
// detected earlier by checking the HTTP request headers changes.
CHECK_EQ(potential_activation.method, common_params_->method);
// Initial prerender navigation can't be a form submission.
CHECK(!common_params_->post_data);
if (potential_activation.post_data != common_params_->post_data) {
return ActivationNavigationParamsMatch::kPostData;
}
// No need to compare source_location, as it's only passed to the DevTools for
// debugging purposes and does not impact the properties of the document
// created by this navigation.
CHECK(!common_params_->started_from_context_menu);
if (potential_activation.started_from_context_menu !=
common_params_->started_from_context_menu) {
return ActivationNavigationParamsMatch::kStartedFromContextMenu;
}
// has_user_gesture doesn't affect any of the security properties of the
// document created by navigation, so equality of the values is not required.
// TODO(crbug.com/40191309): ensure that the user activation status is
// propagated to the activated document.
// text_fragment_token doesn't affect any of the security properties of the
// document created by navigation, so equality of the values is not required.
// TODO(crbug.com/40191311): ensure the activated document consumes
// text_fragment_token and scrolls to the corresponding viewport.
// No need to compare should_check_main_world_csp, as if the CSP blocks the
// initial navigation, it cancels prerendering, and we don't reach here for
// matching. So regardless of the activation's capability to bypass the main
// world CSP, the prerendered page is eligible for the activation. This also
// permits content scripts to activate the page.
if (potential_activation.initiator_origin_trial_features !=
common_params_->initiator_origin_trial_features) {
return ActivationNavigationParamsMatch::kInitiatorOriginTrialFeature;
}
if (potential_activation.href_translate != common_params_->href_translate) {
return ActivationNavigationParamsMatch::kHrefTranslate;
}
// Initial prerender navigation can't be a history navigation.
CHECK(!common_params_->is_history_navigation_in_new_child_frame);
if (potential_activation.is_history_navigation_in_new_child_frame !=
common_params_->is_history_navigation_in_new_child_frame) {
return ActivationNavigationParamsMatch::kIsHistoryNavigationInNewChildFrame;
}
// We intentionally don't check referrer or referrer->policy. See spec
// discussion at https://github.com/WICG/nav-speculation/issues/18.
if (potential_activation.request_destination !=
common_params_->request_destination) {
return ActivationNavigationParamsMatch::kRequestDestination;
}
return ActivationNavigationParamsMatch::kOk;
}
RenderFrameHostImpl* PrerenderHost::GetPrerenderedMainFrameHost() {
CHECK(frame_tree_);
CHECK(frame_tree_->root()->current_frame_host());
return frame_tree_->root()->current_frame_host();
}
FrameTree& PrerenderHost::GetPrerenderFrameTree() {
CHECK(frame_tree_);
return *frame_tree_;
}
void PrerenderHost::RecordFailedFinalStatus(
base::PassKey<PrerenderHostRegistry>,
const PrerenderCancellationReason& reason) {
RecordFailedFinalStatusImpl(reason);
}
void PrerenderHost::RecordFailedFinalStatusImpl(
const PrerenderCancellationReason& reason) {
CHECK(!final_status_);
CHECK_NE(reason.final_status(), PrerenderFinalStatus::kActivated);
final_status_ = reason.final_status();
RecordFailedPrerenderFinalStatus(reason, attributes_);
// Set failure reason for this PreloadingAttempt specific to the
// FinalStatus.
SetFailureReason(reason);
}
void PrerenderHost::RecordActivation(NavigationRequest& navigation_request) {
CHECK(!final_status_);
final_status_ = PrerenderFinalStatus::kActivated;
// TODO(crbug.com/40215894): Replace
// `navigation_request.GetNextPageUkmSourceId()` with prerendered page's UKM
// source ID.
ReportSuccessActivation(attributes_,
navigation_request.GetNextPageUkmSourceId());
}
PrerenderHost::LoadingOutcome PrerenderHost::WaitForLoadStopForTesting() {
LoadingOutcome status = LoadingOutcome::kLoadingCompleted;
if (!frame_tree_->IsLoadingIncludingInnerFrameTrees() &&
GetInitialNavigationId().has_value())
return status;
base::RunLoop loop;
on_wait_loading_finished_ = base::BindOnce(
[](base::OnceClosure on_close, LoadingOutcome* result,
LoadingOutcome status) {
*result = status;
std::move(on_close).Run();
},
loop.QuitClosure(), &status);
loop.Run();
// Reset callback to null in case if loop is quit by timeout.
//
// This `if` body causes SEGV for `kPrerenderingCancelled` case because the
// callback is called in dtor and `this` is already destructed here.
//
// TODO(crbug.com/372691377): Split setup and wait parts and make the wait
// part `static`.
if (status != PrerenderHost::LoadingOutcome::kPrerenderingCancelled) {
on_wait_loading_finished_.Reset();
}
return status;
}
const GURL& PrerenderHost::GetInitialUrl() const {
return attributes_.prerendering_url;
}
void PrerenderHost::AddObserver(Observer* observer) {
observers_.AddObserver(observer);
}
void PrerenderHost::RemoveObserver(Observer* observer) {
observers_.RemoveObserver(observer);
}
std::optional<int64_t> PrerenderHost::GetInitialNavigationId() const {
return initial_navigation_id_;
}
void PrerenderHost::SetInitialNavigation(NavigationRequest* navigation) {
CHECK(!initial_navigation_id_.has_value());
initial_navigation_id_ = navigation->GetNavigationId();
begin_params_ = navigation->begin_params().Clone();
common_params_ = navigation->common_params().Clone();
// The prerendered page should be checked by the main world CSP. See also
// relevant comments in AreCommonNavigationParamsCompatibleWithNavigation().
CHECK_EQ(common_params_->should_check_main_world_csp,
network::mojom::CSPDisposition::CHECK);
}
void PrerenderHost::SetTriggeringOutcome(PreloadingTriggeringOutcome outcome) {
if (attempt_) {
attempt_->SetTriggeringOutcome(outcome);
}
if (devtools_attempt_) {
devtools_attempt_->SetTriggeringOutcome(attributes_, outcome);
}
}
void PrerenderHost::SetFailureReason(
const PrerenderCancellationReason& reason) {
switch (reason.final_status()) {
// When adding a new failure reason, consider whether it should be
// propagated to `attempt_`. Most values should be propagated, but we
// explicitly do not propagate failure reasons if:
// 1. prerender was successfully prepared but then destroyed because it
// wasn't needed for a subsequent navigation (kTriggerDestroyed).
// 2. the prerender was still pending for its initial navigation when it was
// activated (kActivatedBeforeStarted).
case PrerenderFinalStatus::kTriggerDestroyed:
case PrerenderFinalStatus::kActivatedBeforeStarted:
case PrerenderFinalStatus::kTabClosedByUserGesture:
case PrerenderFinalStatus::kTabClosedWithoutUserGesture:
case PrerenderFinalStatus::kSpeculationRuleRemoved:
case PrerenderFinalStatus::kOtherPrerenderedPageActivated:
return;
case PrerenderFinalStatus::kDestroyed:
case PrerenderFinalStatus::kLowEndDevice:
case PrerenderFinalStatus::kInvalidSchemeRedirect:
case PrerenderFinalStatus::kInvalidSchemeNavigation:
case PrerenderFinalStatus::kNavigationRequestBlockedByCsp:
case PrerenderFinalStatus::kMainFrameNavigation:
case PrerenderFinalStatus::kMojoBinderPolicy:
case PrerenderFinalStatus::kRendererProcessCrashed:
case PrerenderFinalStatus::kRendererProcessKilled:
case PrerenderFinalStatus::kDownload:
case PrerenderFinalStatus::kNavigationNotCommitted:
case PrerenderFinalStatus::kNavigationBadHttpStatus:
case PrerenderFinalStatus::kClientCertRequested:
case PrerenderFinalStatus::kNavigationRequestNetworkError:
case PrerenderFinalStatus::kCancelAllHostsForTesting:
case PrerenderFinalStatus::kDidFailLoad:
case PrerenderFinalStatus::kStop:
case PrerenderFinalStatus::kSslCertificateError:
case PrerenderFinalStatus::kLoginAuthRequested:
case PrerenderFinalStatus::kUaChangeRequiresReload:
case PrerenderFinalStatus::kBlockedByClient:
case PrerenderFinalStatus::kMixedContent:
case PrerenderFinalStatus::kTriggerBackgrounded:
case PrerenderFinalStatus::kMemoryLimitExceeded:
case PrerenderFinalStatus::kDataSaverEnabled:
case PrerenderFinalStatus::kTriggerUrlHasEffectiveUrl:
case PrerenderFinalStatus::kInactivePageRestriction:
case PrerenderFinalStatus::kStartFailed:
case PrerenderFinalStatus::kTimeoutBackgrounded:
case PrerenderFinalStatus::kCrossSiteNavigationInInitialNavigation:
case PrerenderFinalStatus::kCrossSiteRedirectInInitialNavigation:
case PrerenderFinalStatus::
kSameSiteCrossOriginRedirectNotOptInInInitialNavigation:
case PrerenderFinalStatus::
kSameSiteCrossOriginNavigationNotOptInInInitialNavigation:
case PrerenderFinalStatus::kActivationNavigationParameterMismatch:
case PrerenderFinalStatus::kActivatedInBackground:
case PrerenderFinalStatus::kEmbedderHostDisallowed:
case PrerenderFinalStatus::kActivationNavigationDestroyedBeforeSuccess:
case PrerenderFinalStatus::kPrimaryMainFrameRendererProcessCrashed:
case PrerenderFinalStatus::kPrimaryMainFrameRendererProcessKilled:
case PrerenderFinalStatus::kActivationFramePolicyNotCompatible:
case PrerenderFinalStatus::kPreloadingDisabled:
case PrerenderFinalStatus::kBatterySaverEnabled:
case PrerenderFinalStatus::kActivatedDuringMainFrameNavigation:
case PrerenderFinalStatus::kPreloadingUnsupportedByWebContents:
case PrerenderFinalStatus::
kSameSiteCrossOriginNavigationNotOptInInMainFrameNavigation:
case PrerenderFinalStatus::
kSameSiteCrossOriginRedirectNotOptInInMainFrameNavigation:
case PrerenderFinalStatus::kCrossSiteNavigationInMainFrameNavigation:
case PrerenderFinalStatus::kCrossSiteRedirectInMainFrameNavigation:
case PrerenderFinalStatus::kMemoryPressureOnTrigger:
case PrerenderFinalStatus::kMemoryPressureAfterTriggered:
case PrerenderFinalStatus::kPrerenderingDisabledByDevTools:
case PrerenderFinalStatus::kActivatedWithAuxiliaryBrowsingContexts:
case PrerenderFinalStatus::kMaxNumOfRunningEagerPrerendersExceeded:
case PrerenderFinalStatus::kMaxNumOfRunningNonEagerPrerendersExceeded:
case PrerenderFinalStatus::kMaxNumOfRunningEmbedderPrerendersExceeded:
case PrerenderFinalStatus::kPrerenderingUrlHasEffectiveUrl:
case PrerenderFinalStatus::kRedirectedPrerenderingUrlHasEffectiveUrl:
case PrerenderFinalStatus::kActivationUrlHasEffectiveUrl:
case PrerenderFinalStatus::kJavaScriptInterfaceAdded:
case PrerenderFinalStatus::kJavaScriptInterfaceRemoved:
case PrerenderFinalStatus::kAllPrerenderingCanceled:
case PrerenderFinalStatus::kWindowClosed:
case PrerenderFinalStatus::kSlowNetwork:
case PrerenderFinalStatus::kV8OptimizerDisabled:
case PrerenderFinalStatus::kPrerenderFailedDuringPrefetch:
if (attempt_) {
attempt_->SetFailureReason(
ToPreloadingFailureReason(reason.final_status()));
// We reset the attempt to ensure we don't update once we have reported
// it as failure or accidentally use it for any other prerender attempts
// as PrerenderHost deletion is async.
attempt_.reset();
}
if (devtools_attempt_) {
devtools_attempt_->SetFailureReason(attributes_, reason);
devtools_attempt_.reset();
}
return;
case PrerenderFinalStatus::kActivated:
// The activation path does not call this method, so it should never reach
// this case.
NOTREACHED();
}
}
std::optional<UrlMatchType> PrerenderHost::IsUrlMatch(const GURL& url) const {
// Triggers are not allowed to treat a cross-origin url as a matched url. It
// would cause security risks.
if (!url::IsSameOriginWith(attributes_.prerendering_url, url)) {
return std::nullopt;
}
std::optional<UrlMatchType> result;
if (GetInitialUrl() == url) {
result = UrlMatchType::kExact;
}
// Check No-Vary-Search header and try and match.
if (!result && no_vary_search_.has_value() &&
no_vary_search_->AreEquivalent(GetInitialUrl(), url)) {
result = UrlMatchType::kNoVarySearch;
}
if (!attributes_.url_match_predicate) {
return result;
}
// Override the result of default url match logic with the result
// from the custom url matching predicate call.
if (attributes_.url_match_predicate.Run(url, result)) {
return UrlMatchType::kURLPredicateMatch;
}
return std::nullopt;
}
bool PrerenderHost::IsNoVarySearchHintUrlMatch(const GURL& url) const {
// Triggers are not allowed to treat a cross-origin url as a matched url. It
// would cause security risks.
if (!url::IsSameOriginWith(attributes_.prerendering_url, url)) {
return false;
}
// We don't care about url_match_predicate here because it is applied only
// if we know for sure url is a match. This is a "potential"
// match depending on the No-Vary-Search header that will be received.
if (attributes_.url_match_predicate) {
return false;
}
// The same as above. We also don't care about the exact match.
if (GetInitialUrl() == url) {
return false;
}
// Let's check if this PrerenderHost would match by
// No-Vary-Search hint. We need to check if the headers were already received.
if (!were_headers_received()) {
if (no_vary_search_expected().has_value() &&
no_vary_search_expected()->AreEquivalent(GetInitialUrl(), url)) {
return true;
}
}
return false;
}
void PrerenderHost::OnAcceptClientHintChanged(
const url::Origin& origin,
const std::vector<network::mojom::WebClientHintsType>& client_hints_type) {
client_hints_type_[origin] = client_hints_type;
}
void PrerenderHost::GetAllowedClientHintsOnPage(
const url::Origin& origin,
blink::EnabledClientHints* client_hints) const {
if (!client_hints_type_.contains(origin))
return;
for (const auto& hint : client_hints_type_.at(origin)) {
client_hints->SetIsEnabled(hint, true);
}
}
std::string PrerenderHost::GetHistogramSuffix() const {
return metric_suffix_;
}
void PrerenderHost::Cancel(PrerenderFinalStatus status) {
TRACE_EVENT("navigation", "PrerenderHost::Cancel", "final_status", status);
// Already cancelled.
if (final_status_)
return;
RenderFrameHostImpl* host = PrerenderHost::GetPrerenderedMainFrameHost();
CHECK(host);
PrerenderHostRegistry* registry =
host->delegate()->GetPrerenderHostRegistry();
CHECK(registry);
registry->CancelHost(frame_tree_node_id_, status);
}
void PrerenderHost::MaybeSetNoVarySearch(
network::mojom::NoVarySearchWithParseError&
no_vary_search_with_parse_error) {
CHECK(!no_vary_search_);
CHECK(!no_vary_search_parse_error_);
if (no_vary_search_with_parse_error.is_parse_error()) {
no_vary_search_parse_error_ =
no_vary_search_with_parse_error.get_parse_error();
return;
}
CHECK(no_vary_search_with_parse_error.is_no_vary_search());
net::HttpNoVarySearchData no_vary_search =
no_vary_search::ParseHttpNoVarySearchDataFromMojom(
no_vary_search_with_parse_error.get_no_vary_search());
if (attempt_) {
static_cast<PreloadingAttemptImpl*>(attempt_.get())
->SetNoVarySearchMatchPredicate(base::BindRepeating(
[](net::HttpNoVarySearchData no_vary_search, const GURL& a,
const GURL& b) { return no_vary_search.AreEquivalent(a, b); },
no_vary_search, GetInitialUrl()));
}
no_vary_search_ = std::move(no_vary_search);
}
bool PrerenderHost::IsInitialNavigation(
const NavigationRequest& navigation_request) const {
return GetInitialNavigationId() == navigation_request.GetNavigationId();
}
base::TimeDelta PrerenderHost::WaitUntilHeadTimeout() {
int timeout_in_milliseconds = 0;
if (IsSpeculationRuleType(attributes_.trigger_type)) {
CHECK(attributes_.eagerness.has_value());
switch (attributes_.eagerness.value()) {
case blink::mojom::SpeculationEagerness::kEager:
timeout_in_milliseconds =
features::kPrerender2NoVarySearchWaitForHeadersTimeoutEagerPrerender
.Get();
break;
case blink::mojom::SpeculationEagerness::kModerate:
timeout_in_milliseconds =
features::
kPrerender2NoVarySearchWaitForHeadersTimeoutModeratePrerender
.Get();
break;
case blink::mojom::SpeculationEagerness::kConservative:
timeout_in_milliseconds =
features::
kPrerender2NoVarySearchWaitForHeadersTimeoutConservativePrerender
.Get();
break;
}
} else {
timeout_in_milliseconds =
features::kPrerender2NoVarySearchWaitForHeadersTimeoutForEmbedders
.Get();
}
return base::Milliseconds(timeout_in_milliseconds);
}
void PrerenderHost::OnWaitingForHeadersStarted(
NavigationHandle& navigation_handle,
WaitingForHeadersStartedReason reason) {
// Prerender frame tree is alive. This check is also done by the caller.
CHECK(frame_tree_);
for (auto& observer : observers_) {
observer.OnWaitingForHeadersStarted(navigation_handle, reason);
}
}
void PrerenderHost::OnWaitingForHeadersFinished(
NavigationHandle& navigation_handle,
WaitingForHeadersFinishedReason reason) {
// Prerender frame tree is alive. This check is also done by the caller.
CHECK(frame_tree_);
base::UmaHistogramEnumeration(
"Prerender.Experimental.WaitingForHeadersFinishedReason" +
GetHistogramSuffix(),
reason);
for (auto& observer : observers_) {
observer.OnWaitingForHeadersFinished(navigation_handle, reason);
}
}
bool PrerenderHost::ShouldAbortNavigationBecausePrefetchUnavailable() const {
CHECK(base::FeatureList::IsEnabled(
features::kPrerender2FallbackPrefetchSpecRules));
auto is_prefetch_used =
[](const std::optional<PrefetchStatus>& prefetch_status) -> bool {
if (!prefetch_status.has_value()) {
return false;
}
switch (prefetch_status.value()) {
case PrefetchStatus::kPrefetchResponseUsed:
return true;
case PrefetchStatus::kPrefetchNotUsedProbeFailed:
case PrefetchStatus::kPrefetchNotStarted:
case PrefetchStatus::kPrefetchIneligibleUserHasCookies:
case PrefetchStatus::kPrefetchIneligibleUserHasServiceWorker:
case PrefetchStatus::kPrefetchIneligibleSchemeIsNotHttps:
case PrefetchStatus::kPrefetchIneligibleNonDefaultStoragePartition:
case PrefetchStatus::kPrefetchNotFinishedInTime:
case PrefetchStatus::kPrefetchFailedNetError:
case PrefetchStatus::kPrefetchFailedNon2XX:
case PrefetchStatus::kPrefetchFailedMIMENotSupported:
case PrefetchStatus::kPrefetchSuccessful:
case PrefetchStatus::kPrefetchIneligibleRetryAfter:
case PrefetchStatus::kPrefetchIneligiblePrefetchProxyNotAvailable:
case PrefetchStatus::kPrefetchIsPrivacyDecoy:
case PrefetchStatus::kPrefetchIsStale:
case PrefetchStatus::kPrefetchNotUsedCookiesChanged:
case PrefetchStatus::kPrefetchIneligibleHostIsNonUnique:
case PrefetchStatus::kPrefetchIneligibleDataSaverEnabled:
case PrefetchStatus::kPrefetchIneligibleExistingProxy:
case PrefetchStatus::kPrefetchHeldback:
case PrefetchStatus::kPrefetchAllowed:
case PrefetchStatus::kPrefetchFailedInvalidRedirect:
case PrefetchStatus::kPrefetchFailedIneligibleRedirect:
case PrefetchStatus::
kPrefetchIneligibleSameSiteCrossOriginPrefetchRequiredProxy:
case PrefetchStatus::kPrefetchIneligibleBatterySaverEnabled:
case PrefetchStatus::kPrefetchIneligiblePreloadingDisabled:
case PrefetchStatus::kPrefetchEvictedAfterCandidateRemoved:
case PrefetchStatus::kPrefetchEvictedForNewerPrefetch:
return false;
}
};
auto is_ineligibility_admissible =
[](PreloadingEligibility prefetch_eligibility) -> bool {
switch (prefetch_eligibility) {
// Prefetch is not available if SW exists, but prerender is.
case PreloadingEligibility::kUserHasServiceWorker:
// Prefetch is not available for HTTP, but prerender is available
// for HTTPS/HTTP.
case PreloadingEligibility::kSchemeIsNotHttps:
return true;
case PreloadingEligibility::kEligible:
case PreloadingEligibility::kUnspecified:
case PreloadingEligibility::kPreloadingDisabled:
case PreloadingEligibility::kHidden:
case PreloadingEligibility::kCrossOrigin:
case PreloadingEligibility::kLowMemory:
case PreloadingEligibility::kJavascriptDisabled:
case PreloadingEligibility::kDataSaverEnabled:
case PreloadingEligibility::kHasEffectiveUrl:
case PreloadingEligibility::kSingleProcess:
case PreloadingEligibility::kLinkRelNext:
case PreloadingEligibility::kThirdPartyCookies:
case PreloadingEligibility::kPreloadingInvokedWithinTimelimit:
case PreloadingEligibility::kRendererProcessLimitExceeded:
case PreloadingEligibility::kBatterySaverEnabled:
case PreloadingEligibility::kPreloadingUnsupportedByWebContents:
case PreloadingEligibility::kMemoryPressure:
case PreloadingEligibility::kPreloadingDisabledByDevTools:
case PreloadingEligibility::kHttpsOnly:
case PreloadingEligibility::kHttpOrHttpsOnly:
case PreloadingEligibility::kSlowNetwork:
case PreloadingEligibility::kV8OptimizerDisabled:
case PreloadingEligibility::kUserHasCookies:
case PreloadingEligibility::kNonDefaultStoragePartition:
case PreloadingEligibility::kRetryAfter:
case PreloadingEligibility::kPrefetchProxyNotAvailable:
case PreloadingEligibility::kHostIsNonUnique:
case PreloadingEligibility::kExistingProxy:
case PreloadingEligibility::kSameSiteCrossOriginPrefetchRequiredProxy:
case PreloadingEligibility::kPreloadingEligibilityContentEnd:
case PreloadingEligibility::kPreloadingEligibilityContentStart2:
case PreloadingEligibility::kPreloadingEligibilityContentEnd2:
return false;
}
};
// If a prerender navigation reached to `PrefetchURLLoaderInterceptor`, it is
// blocked by `PrefetchMatchResolver2` and prefetch ahead of prerender. So, we
// should've got prefetch eligibility when it reached to
// `PrerenderURLLoaderThrottle`. Therefore, if prefetch eligibility is
// `PreloadingEligibility::kUnspecified`, it implies that the navigation is
// handled by other `NavigationLoaderInterceptor` earlier than
// `PrefetchURLLoaderInterceptor`. In this case, the interceptor already
// decided to serve a resource for the navigation. So, we don't need to abort
// this prerender.
//
// For example, if a service worker is installed to the given URL,
// `ServiceWorkerMainResourceLoaderInterceptor` intercepts the navigation.
// `PrefetchService` may or may not report prefetch eligibility at this
// timing, but eventually reports
// `PreloadingEligibility::kUserHasServiceWorker`. So, continuing the
// navigation is reasonable.
auto nav_is_likely_handled_by_earlier_interceptor =
[](PreloadingEligibility prefetch_eligibility) -> bool {
return prefetch_eligibility == PreloadingEligibility::kUnspecified;
};
// Use a prefetch (in many cases, aheaf of prerender) if it is about to be
// used.
if (is_prefetch_used(attributes_.preload_pipeline_info->prefetch_status())) {
return false;
}
// Fallback to normal navigation if the prefetch was ineligible that is
// admissible.
if (is_ineligibility_admissible(
attributes_.preload_pipeline_info->prefetch_eligibility())) {
return false;
}
// Continue if the navigation is handled by an earlier interceptor.
if (nav_is_likely_handled_by_earlier_interceptor(
attributes_.preload_pipeline_info->prefetch_eligibility())) {
return false;
}
// Otherwise, abort this prerender.
return true;
}
} // namespace content