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content / browser / loader / keep_alive_url_loader.cc [blame]
// Copyright 2023 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/loader/keep_alive_url_loader.h"
#include <memory>
#include <utility>
#include <vector>
#include "base/check_is_test.h"
#include "base/feature_list.h"
#include "base/functional/bind.h"
#include "base/functional/callback_forward.h"
#include "base/metrics/histogram_functions.h"
#include "base/strings/strcat.h"
#include "base/trace_event/trace_event.h"
#include "base/trace_event/typed_macros.h"
#include "base/unguessable_token.h"
#include "content/browser/devtools/devtools_instrumentation.h"
#include "content/browser/loader/keep_alive_attribution_request_helper.h"
#include "content/browser/renderer_host/mixed_content_checker.h"
#include "content/browser/renderer_host/policy_container_host.h"
#include "content/browser/renderer_host/render_frame_host_impl.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/browser_thread.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/common/content_client.h"
#include "content/public/common/url_utils.h"
#include "net/base/load_flags.h"
#include "net/http/http_request_headers.h"
#include "services/network/public/cpp/content_security_policy/content_security_policy.h"
#include "services/network/public/cpp/content_security_policy/csp_context.h"
#include "services/network/public/cpp/devtools_observer_util.h"
#include "services/network/public/cpp/shared_url_loader_factory.h"
#include "services/network/public/cpp/url_loader_completion_status.h"
#include "services/network/public/mojom/content_security_policy.mojom.h"
#include "services/network/public/mojom/early_hints.mojom.h"
#include "services/network/public/mojom/fetch_api.mojom-shared.h"
#include "services/network/public/mojom/url_request.mojom.h"
#include "third_party/blink/public/common/features.h"
namespace content {
namespace {
// Internally enforces a limit to allow a loader outlive its renderer after
// receiving disconnection notification from the renderer.
//
// Defaults to 30s, the same as pre-migration's timeout.
constexpr base::TimeDelta kDefaultDisconnectedKeepAliveURLLoaderTimeout =
base::Seconds(30);
base::TimeDelta GetDisconnectedKeepAliveURLLoaderTimeout() {
return base::Seconds(GetFieldTrialParamByFeatureAsInt(
blink::features::kKeepAliveInBrowserMigration,
"disconnected_loader_timeout_seconds",
base::checked_cast<int32_t>(
kDefaultDisconnectedKeepAliveURLLoaderTimeout.InSeconds())));
}
// These values are persisted to logs. Entries should not be renumbered and
// numeric values should never be reused.
//
// Must remain in sync with FetchLaterBrowserMetricType in
// tools/metrics/histograms/enums.xml.
enum class FetchLaterBrowserMetricType {
kAbortedByInitiator = 0,
kStartedAfterInitiatorDisconnected = 1,
kStartedByInitiator = 2,
kCancelledAfterTimeLimit = 3,
kStartedWhenShutdown = 4,
kMaxValue = kStartedWhenShutdown,
};
void LogFetchLaterMetric(const FetchLaterBrowserMetricType& type) {
base::UmaHistogramEnumeration("FetchLater.Browser.Metrics", type);
}
// A ContentSecurityPolicy context for KeepAliveURLLoader.
class KeepAliveURLLoaderCSPContext final : public network::CSPContext {
public:
// network::CSPContext override:
void ReportContentSecurityPolicyViolation(
network::mojom::CSPViolationPtr violation_params) final {
// TODO(crbug.com/40236167): Support reporting violation w/o renderer.
}
void SanitizeDataForUseInCspViolation(
network::mojom::CSPDirectiveName directive,
GURL* blocked_url,
network::mojom::SourceLocation* source_location) const final {
// TODO(crbug.com/40236167): Support reporting violation w/o renderer.
}
};
// Checks if `url` is allowed by the set of Content-Security-Policy `policies`.
// Violation will not be reported back to renderer, as this function must be
// called after renderer is gone.
// TODO(crbug.com/40263403): Isolated world's CSP is not handled.
bool IsRedirectAllowedByCSP(
const std::vector<network::mojom::ContentSecurityPolicyPtr>& policies,
const GURL& url,
const GURL& url_before_redirects,
bool has_followed_redirect) {
// Sets the CSP Directive for fetch() requests. See
// https://w3c.github.io/webappsec-csp/#directive-connect-src
// https://fetch.spec.whatwg.org/#destination-table
auto directive = network::mojom::CSPDirectiveName::ConnectSrc;
// Sets empty as source location is only used when reporting back to renderer.
auto empty_source_location = network::mojom::SourceLocation::New();
auto disposition = network::CSPContext::CheckCSPDisposition::CHECK_ALL_CSP;
// When reaching here, renderer should have be gone, or at least
// `KeepAliveURLLoader::forwarding_client_` is disconnected.
return KeepAliveURLLoaderCSPContext()
.IsAllowedByCsp(policies, directive, url, url_before_redirects,
has_followed_redirect, empty_source_location, disposition,
/*is_form_submission=*/false)
.IsAllowed();
}
} // namespace
// A wrapper class around the target URLLoaderClient connected to Renderer,
// where the owning KeepAliveURLLoader forwards the network loading results to.
class KeepAliveURLLoader::ForwardingClient final
: public network::mojom::URLLoaderClient {
public:
ForwardingClient(
KeepAliveURLLoader* loader,
mojo::PendingRemote<network::mojom::URLLoaderClient> forwarding_client)
: keep_alive_url_loader_(std::move(loader)),
target_(std::move(forwarding_client)) {
CHECK(keep_alive_url_loader_);
// For FetchLater requests, `target_` is not bound to renderer.
if (target_) {
target_.set_disconnect_handler(base::BindOnce(
&ForwardingClient::OnDisconnected, base::Unretained(this)));
}
}
// Not copyable.
ForwardingClient(const ForwardingClient&) = delete;
ForwardingClient& operator=(const ForwardingClient&) = delete;
int32_t request_id() const { return keep_alive_url_loader_->request_id_; }
bool IsConnected() const { return !!target_; }
void OnDisconnected();
// network::mojom::URLLoaderClient overrides:
void OnReceiveEarlyHints(network::mojom::EarlyHintsPtr early_hints) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading",
"KeepAliveURLLoader::ForwardingClient::OnReceiveEarlyHints",
"request_id", request_id());
if (IsConnected()) {
// The renderer is alive, forwards the action.
target_->OnReceiveEarlyHints(std::move(early_hints));
return;
}
}
void OnUploadProgress(int64_t current_position,
int64_t total_size,
base::OnceCallback<void()> callback) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading",
"KeepAliveURLLoader::ForwardingClient::OnUploadProgress",
"request_id", request_id());
if (IsConnected()) {
// The renderer is alive, forwards the action.
target_->OnUploadProgress(current_position, total_size,
std::move(callback));
return;
}
}
void OnTransferSizeUpdated(int32_t transfer_size_diff) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading",
"KeepAliveURLLoader::ForwardingClient::OnTransferSizeUpdated",
"request_id", request_id());
if (IsConnected()) {
// The renderer is alive, forwards the action.
target_->OnTransferSizeUpdated(transfer_size_diff);
return;
}
}
void OnReceiveRedirect(const net::RedirectInfo& redirect_info,
network::mojom::URLResponseHeadPtr head) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
CHECK(IsConnected());
target_->OnReceiveRedirect(redirect_info, std::move(head));
}
void OnReceiveResponse(
network::mojom::URLResponseHeadPtr head,
mojo::ScopedDataPipeConsumerHandle body,
std::optional<mojo_base::BigBuffer> cached_metadata) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
CHECK(IsConnected());
target_->OnReceiveResponse(std::move(head), std::move(body),
std::move(cached_metadata));
}
void OnComplete(
const network::URLLoaderCompletionStatus& completion_status) override {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
CHECK(IsConnected());
target_->OnComplete(completion_status);
}
private:
// Cannot be nullptr as it owns `this`.
const raw_ptr<KeepAliveURLLoader> keep_alive_url_loader_;
// The target where overridden the `network::mojom::URLLoaderClient` methods
// should forward to.
// Its receiver resides in the Renderer.
mojo::Remote<network::mojom::URLLoaderClient> target_;
};
// Stores the chain of redriects, response, and completion status, such that
// they can be forwarded to renderer after handled in browser first.
// See also `ForwardURLLoad()`.
struct KeepAliveURLLoader::StoredURLLoad {
StoredURLLoad() = default;
// Not copyable.
StoredURLLoad(const StoredURLLoad&) = delete;
StoredURLLoad& operator=(const StoredURLLoad&) = delete;
// Stores data for a redirect received from `OnReceiveRedirect()`.
struct RedirectData {
RedirectData(const net::RedirectInfo& redirect_info,
network::mojom::URLResponseHeadPtr response_head)
: info(redirect_info), head(std::move(response_head)) {}
// Not copyable.
RedirectData(const RedirectData&) = delete;
RedirectData& operator=(const RedirectData&) = delete;
// A copy of the RedirectInfo.
net::RedirectInfo info;
// The original URLResponseHead not yet passed to renderer.
network::mojom::URLResponseHeadPtr head;
};
// Stores data for a response received from `OnReceiveResponse()`.
struct ResponseData {
ResponseData(network::mojom::URLResponseHeadPtr response_head,
mojo::ScopedDataPipeConsumerHandle body_handle,
std::optional<mojo_base::BigBuffer> cached_metadata)
: head(std::move(response_head)),
body(std::move(body_handle)),
metadata(std::move(cached_metadata)) {}
// Not copyable.
ResponseData(const ResponseData&) = delete;
ResponseData& operator=(const ResponseData&) = delete;
// The original URLResponseHead not yet passed to renderer.
network::mojom::URLResponseHeadPtr head;
// The original body handle not yet passed to renderer.
mojo::ScopedDataPipeConsumerHandle body;
// The original cached metadata not yet passed to renderer.
std::optional<mojo_base::BigBuffer> metadata;
};
// Stores all intermediate redirect data received from `OnReceiveRedirect()`.
std::queue<std::unique_ptr<RedirectData>> redirects;
// Stores the response data received from `OnReceiveResponse()` for later use
// in renderer.
std::unique_ptr<ResponseData> response = nullptr;
// Stores the completion status received from `OnComplete()` for later use in
// renderer.
std::optional<network::URLLoaderCompletionStatus> completion_status =
std::nullopt;
// Tells whether any of the above field has been used (forwarded to renderer).
bool forwarding = false;
};
KeepAliveURLLoader::KeepAliveURLLoader(
int32_t request_id,
uint32_t options,
const network::ResourceRequest& resource_request,
mojo::PendingRemote<network::mojom::URLLoaderClient> forwarding_client,
const net::MutableNetworkTrafficAnnotationTag& traffic_annotation,
scoped_refptr<network::SharedURLLoaderFactory> network_loader_factory,
scoped_refptr<PolicyContainerHost> policy_container_host,
WeakDocumentPtr weak_document_ptr,
BrowserContext* browser_context,
URLLoaderThrottlesGetter throttles_getter,
base::PassKey<KeepAliveURLLoaderService>,
std::unique_ptr<KeepAliveAttributionRequestHelper>
attribution_request_helper)
: request_id_(request_id),
devtools_request_id_(base::UnguessableToken::Create().ToString()),
options_(options),
resource_request_(resource_request),
forwarding_client_(
std::make_unique<ForwardingClient>(this,
std::move(forwarding_client))),
traffic_annotation_(traffic_annotation),
network_loader_factory_(std::move(network_loader_factory)),
stored_url_load_(std::make_unique<StoredURLLoad>()),
policy_container_host_(std::move(policy_container_host)),
weak_document_ptr_(std::move(weak_document_ptr)),
browser_context_(browser_context),
initial_url_(resource_request.url),
last_url_(resource_request.url),
throttles_getter_(throttles_getter),
attribution_request_helper_(std::move(attribution_request_helper)) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
CHECK(network_loader_factory_);
CHECK(policy_container_host_);
CHECK(!resource_request.trusted_params);
CHECK(browser_context_);
TRACE_EVENT("loading", "KeepAliveURLLoader::KeepAliveURLLoader", "request_id",
request_id_, "url", last_url_);
TRACE_EVENT_NESTABLE_ASYNC_BEGIN1("loading", "KeepAliveURLLoader",
request_id_, "url", last_url_);
LogFetchKeepAliveRequestMetric("Total");
if (IsFetchLater()) {
base::UmaHistogramBoolean("FetchLater.Browser.Total", true);
}
}
void KeepAliveURLLoader::Start() {
CHECK(!is_started_);
TRACE_EVENT("loading", "KeepAliveURLLoader::Start", "request_id",
request_id_);
is_started_ = true;
LogFetchKeepAliveRequestMetric("Started");
if (IsFetchLater()) {
base::UmaHistogramBoolean("FetchLater.Browser.Total.Started", true);
// Logs to DevTools only if the initiator is still alive.
if (auto* rfh = GetInitiator(); rfh) {
devtools_instrumentation::OnFetchKeepAliveRequestWillBeSent(
rfh->frame_tree_node(), devtools_request_id_, resource_request_);
}
}
GetContentClient()->browser()->OnKeepaliveRequestStarted(browser_context_);
// Asks the network service to create a URL loader with passed in params.
url_loader_ = blink::ThrottlingURLLoader::CreateLoaderAndStart(
network_loader_factory_, throttles_getter_.Run(), request_id_, options_,
&resource_request_, forwarding_client_.get(),
net::NetworkTrafficAnnotationTag(traffic_annotation_),
base::SingleThreadTaskRunner::GetCurrentDefault(),
/*cors_exempt_header_list=*/std::nullopt,
// `this`'s lifetime is at least the same as `url_loader_`.
/*client_receiver_delegate=*/this);
// `url_loader_` now re-runs a subset of throttles that have been run
// in renderer, which is necessary to handle in-browser redirects.
// There is already a similar use case that also runs throttles in browser in
// `SearchPrefetchRequest::StartPrefetchRequest()`. The review discussion in
// https://crrev.com/c/2552723/3 suggests that running them again in browser
// is fine.
}
KeepAliveURLLoader::~KeepAliveURLLoader() {
TRACE_EVENT("loading", "KeepAliveURLLoader::~KeepAliveURLLoader",
"request_id", request_id_);
TRACE_EVENT_NESTABLE_ASYNC_END0("loading", "KeepAliveURLLoader", request_id_);
disconnected_loader_timer_.Stop();
if (IsStarted()) {
GetContentClient()->browser()->OnKeepaliveRequestFinished();
}
}
void KeepAliveURLLoader::set_on_delete_callback(
OnDeleteCallback on_delete_callback) {
on_delete_callback_ = std::move(on_delete_callback);
}
base::WeakPtr<KeepAliveURLLoader> KeepAliveURLLoader::GetWeakPtr() {
return weak_ptr_factory_.GetWeakPtr();
}
bool KeepAliveURLLoader::IsStarted() const {
return is_started_;
}
RenderFrameHostImpl* KeepAliveURLLoader::GetInitiator() const {
return static_cast<RenderFrameHostImpl*>(
weak_document_ptr_.AsRenderFrameHostIfValid());
}
void KeepAliveURLLoader::FollowRedirect(
const std::vector<std::string>& removed_headers,
const net::HttpRequestHeaders& modified_headers,
const net::HttpRequestHeaders& modified_cors_exempt_headers,
const std::optional<GURL>& new_url) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::FollowRedirect", "request_id",
request_id_, "url", new_url);
if (new_url != std::nullopt) {
mojo::ReportBadMessage(
"Unexpected `new_url` in KeepAliveURLLoader::FollowRedirect(): "
"must be null");
return;
}
if (IsRendererConnected()) {
// Continue forwarding the stored data to renderer.
// Note: we may or may not have response at this point.
ForwardURLLoad();
// DO NOT touch any members after this line. `this` may be already deleted
// if `OnComplete()` has been triggered.
return;
}
// No need to forward anymore as the target renderer is gone.
DeleteSelf();
// DO NOT touch any members after this line. `this` is deleted.
}
void KeepAliveURLLoader::SetPriority(net::RequestPriority priority,
int intra_priority_value) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::SetPriority", "request_id",
request_id_);
// Let `url_loader_` handles how to forward the action to the network service.
url_loader_->SetPriority(priority, intra_priority_value);
}
void KeepAliveURLLoader::PauseReadingBodyFromNet() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::PauseReadingBodyFromNet",
"request_id", request_id_);
if (HasReceivedResponse()) {
// This may come from a renderer that tries to process a redirect which has
// been previously handled in this loader.
return;
}
// Let `url_loader_` handles how to forward the action to the network service.
url_loader_->PauseReadingBodyFromNet();
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->PauseReadingBodyFromNetProcessed(this);
}
}
// TODO(crbug.com/40236167): Add test coverage.
void KeepAliveURLLoader::ResumeReadingBodyFromNet() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::ResumeReadingBodyFromNet",
"request_id", request_id_);
if (HasReceivedResponse()) {
// This may come from a renderer that tries to process a redirect which has
// been previously handled in this loader.
return;
}
// Let `url_loader_` handles how to forward the action to the network service.
url_loader_->ResumeReadingBodyFromNet();
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->ResumeReadingBodyFromNetProcessed(this);
}
}
void KeepAliveURLLoader::EndReceiveRedirect(
const net::RedirectInfo& redirect_info,
network::mojom::URLResponseHeadPtr head) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::EndReceiveRedirect", "request_id",
request_id_);
// Throttles from content-embedder has already been run for this redirect.
// See also the call sequence from renderer:
// https://docs.google.com/document/d/1ZzxMMBvpqn8VZBZKnb7Go8TWjnrGcXuLS_USwVVRUvY/edit?pli=1#heading=h.d006i46pmq9
if (IsFetchLater()) {
// Logs to DevTools only if the initiator is still alive.
if (auto* rfh = GetInitiator(); rfh) {
auto redirect_head_info = network::ExtractDevToolsInfo(*head);
std::pair<const GURL&, const network::mojom::URLResponseHeadDevToolsInfo&>
redirect_info_for_devtools{last_url_, *redirect_head_info};
devtools_instrumentation::OnFetchKeepAliveRequestWillBeSent(
rfh->frame_tree_node(), devtools_request_id_, resource_request_,
redirect_info_for_devtools);
}
}
if (attribution_request_helper_) {
attribution_request_helper_->OnReceiveRedirect(head->headers.get(),
redirect_info.new_url);
}
// Stores the redirect data for later use by renderer.
stored_url_load_->redirects.emplace(
std::make_unique<StoredURLLoad::RedirectData>(redirect_info,
std::move(head)));
// Runs additional redirect checks before proceeding.
if (net::Error err = WillFollowRedirect(redirect_info); err != net::OK) {
OnComplete(network::URLLoaderCompletionStatus(err));
return;
}
// TODO(crbug.com/40236167): Figure out how to deal with lost
// ResourceFetcher's counter & dev console logging (renderer is dead).
resource_request_.url = redirect_info.new_url;
resource_request_.site_for_cookies = redirect_info.new_site_for_cookies;
resource_request_.referrer = GURL(redirect_info.new_referrer);
resource_request_.referrer_policy = redirect_info.new_referrer_policy;
// Ask the network service to follow the redirect.
last_url_ = GURL(redirect_info.new_url);
// TODO(crbug.com/40880984): Remove Authorization header upon cross-origin
// redirect.
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnReceiveRedirectProcessed(this);
}
// Asks `url_loader_` to directly forward the action to the network service.
// The modified headers are stored there, if exists.
//
// Note: there may be throttles running in IO thread, which may send signals
// in between `FollowRedirect()` and the next `OnReceiveRedirect()` or
// `OnReceiveResponse()`.
url_loader_->FollowRedirect(
/*removed_headers=*/{}, /*modified_headers=*/{},
/*modified_cors_exempt_headers=*/{});
}
void KeepAliveURLLoader::OnReceiveResponse(
network::mojom::URLResponseHeadPtr response,
mojo::ScopedDataPipeConsumerHandle body,
std::optional<mojo_base::BigBuffer> cached_metadata) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::OnReceiveResponse", "request_id",
request_id_, "url", last_url_);
LogFetchKeepAliveRequestMetric("Succeeded");
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnReceiveResponse(this);
}
if (IsFetchLater()) {
// Logs to DevTools only if the initiator is still alive.
if (auto* rfh = GetInitiator(); rfh) {
devtools_instrumentation::OnFetchKeepAliveResponseReceived(
rfh->frame_tree_node(), devtools_request_id_, last_url_, *response);
}
}
if (attribution_request_helper_) {
attribution_request_helper_->OnReceiveResponse(response->headers.get());
attribution_request_helper_.reset();
}
// In case the renderer is alive, the stored response data will be forwarded
// at the end of `ForwardURLLoad()`.
stored_url_load_->response = std::make_unique<StoredURLLoad::ResponseData>(
std::move(response), std::move(body), std::move(cached_metadata));
if (IsRendererConnected()) {
// Starts to forward the stored redirects/response to renderer.
// Note that `OnComplete()` may be triggered in between the forwarding.
ForwardURLLoad();
// DO NOT touch any members after this line. `this` may be already deleted
// if `OnComplete()` has been triggered.
return;
}
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnReceiveResponseProcessed(this);
}
// When reaching here, the loader counterpart in renderer is already
// disconnected before receiving response. However, the renderer may still be
// alive, and waiting for DevTools logger to finish with `OnComplete()`. For
// examples:
// 1. Calling fetchLater(url, {activateAfter: 0}) will immediately dispose
// renderer loader, which is independent of renderer lifetime and requires
// OnComplete().
// 2. Calling fetch(url, {keepalive: true}) in unload may lead to disconnected
// renderer loader + dead renderer, which requires no OnComplete().
//
// Only for case 1, we want to wait for a limited time to allow `OnComplete()`
// to trigger, but also prevents this loader from staying alive indefinitely.
if (IsFetchLater() && !disconnected_loader_timer_.IsRunning()) {
disconnected_loader_timer_.Start(
FROM_HERE, GetDisconnectedKeepAliveURLLoaderTimeout(),
base::BindOnce(&KeepAliveURLLoader::OnDisconnectedLoaderTimerFired,
// `this` owns `disconnected_loader_timer_`.
base::Unretained(this)));
return;
}
// Otherwise, no need to wait for `OnComplete()`.
// This loader should be deleted immediately to avoid hanged requests taking
// up resources.
DeleteSelf();
// DO NOT touch any members after this line. `this` is already deleted.
}
void KeepAliveURLLoader::OnComplete(
const network::URLLoaderCompletionStatus& completion_status) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::OnComplete", "request_id",
request_id_);
if (completion_status.error_code != net::OK) {
// If the request succeeds, it should've been logged in `OnReceiveResponse`.
LogFetchKeepAliveRequestMetric("Failed");
}
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnComplete(this, completion_status);
}
if (IsFetchLater()) {
// Logs to DevTools only if the initiator is still alive.
if (auto* rfh = GetInitiator(); rfh) {
devtools_instrumentation::OnFetchKeepAliveRequestComplete(
rfh->frame_tree_node(), devtools_request_id_, completion_status);
}
}
// In case the renderer is alive, the stored status will be forwarded
// at the end of `ForwardURLLoad()`.
stored_url_load_->completion_status = completion_status;
if (IsRendererConnected()) {
if (HasReceivedResponse()) {
// Do nothing. `completion_status` will be forwarded at the end of
// `ForwardURLLoad()`.
return;
}
// Either (1) an error happens in between redirect handling in browser, or
// (2) the redirects and response have all been forwarded.
// Starts forwarding stored redirects and the completion status to renderer.
ForwardURLLoad();
// DO NOT touch any members after this line. `this` is already deleted.
return;
}
// TODO(crbug.com/40236167): Handle in the browser process.
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnCompleteProcessed(this, completion_status);
}
DeleteSelf();
// DO NOT touch any members after this line. `this` is already deleted.
}
bool KeepAliveURLLoader::HasReceivedResponse() const {
return stored_url_load_ && stored_url_load_->response != nullptr;
}
void KeepAliveURLLoader::ForwardURLLoad() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
CHECK(IsRendererConnected());
CHECK(stored_url_load_);
// Forwards the redirects/response/completion in the exact sequence.
stored_url_load_->forwarding = true;
if (!stored_url_load_->redirects.empty()) {
// All redirects have been handled in the browser. However, redirects must
// also be processed by the renderer so that it knows what URL the
// response come from when parsing the response.
//
// Note: The renderer might get shut down before
// `forwarding_client_->OnReceiveRedirect()` finish all redirect handling.
// In such case, the handling will be taken over by browser from
// `OnRendererConnectionError()`.
forwarding_client_->OnReceiveRedirect(
stored_url_load_->redirects.front()->info,
std::move(stored_url_load_->redirects.front()->head));
stored_url_load_->redirects.pop();
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnReceiveRedirectForwarded(this);
}
// The rest of `stored_url_load_->redirects` will be forwarded in the next
// visit to this method when `FollowRedirect()` is called by the renderer.
return;
}
if (stored_url_load_->response) {
// Note: The receiver may fail to finish reading the entire
// `stored_url_load_->response`response`, so response caching is not
// guaranteed.
// Note: The renderer might get shut down before
// `forwarding_client_->OnReceiveResponse()` finish response handling.
// In such case, the attributionsrc handling cannot be dropped and should be
// taken over by browser in `OnRendererConnectionError().
forwarding_client_->OnReceiveResponse(
std::move(stored_url_load_->response->head),
std::move(stored_url_load_->response->body),
std::move(stored_url_load_->response->metadata));
stored_url_load_->response = nullptr;
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnReceiveResponseForwarded(this);
}
}
if (stored_url_load_->completion_status.has_value()) {
forwarding_client_->OnComplete(*(stored_url_load_->completion_status));
if (observer_for_testing_) {
CHECK_IS_TEST();
observer_for_testing_->OnCompleteForwarded(
this, *(stored_url_load_->completion_status));
}
stored_url_load_ = nullptr;
DeleteSelf();
// DO NOT touch any members after this line. `this` is already deleted.
}
}
bool KeepAliveURLLoader::IsForwardURLLoadStarted() const {
return stored_url_load_ && stored_url_load_->forwarding;
}
bool KeepAliveURLLoader::IsRendererConnected() const {
CHECK(forwarding_client_);
return forwarding_client_->IsConnected();
}
net::Error KeepAliveURLLoader::WillFollowRedirect(
const net::RedirectInfo& redirect_info) const {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
// TODO(crbug.com/40236167): Add logic to handle redirecting to extensions
// from `ChromeContentRendererClient::IsSafeRedirectTarget()`.
if (!IsSafeRedirectTarget(last_url_, redirect_info.new_url)) {
return net::ERR_UNSAFE_REDIRECT;
}
if (resource_request_.redirect_mode == network::mojom::RedirectMode::kError) {
return net::ERR_FAILED;
}
if (resource_request_.redirect_mode !=
network::mojom::RedirectMode::kManual) {
// Checks if redirecting to `redirect_info.new_url` is allowed by
// ContentSecurityPolicy from the request initiator document.
if (!IsRedirectAllowedByCSP(
policy_container_host_->policies().content_security_policies,
redirect_info.new_url, initial_url_, last_url_ != initial_url_)) {
return net::ERR_BLOCKED_BY_CSP;
}
// Checks if redirecting to `redirect_info.new_url` is allowed by
// MixedContent checker.
// TODO(crbug.com/40941240): Figure out how to check without a frame.
if (auto* rfh = GetInitiator();
rfh && MixedContentChecker::ShouldBlockFetchKeepAlive(
rfh, redirect_info.new_url,
/*for_redirect=*/true)) {
return net::ERR_FAILED;
}
}
return net::OK;
}
void KeepAliveURLLoader::CancelWithStatus(
const network::URLLoaderCompletionStatus& status) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::CancelWithStatus", "request_id",
request_id_);
if (!stored_url_load_->completion_status.has_value()) {
// Only logs if there is no error logged by `OnComplete()` yet.
LogFetchKeepAliveRequestMetric("Failed");
}
// This method can be triggered when one of the followings happen:
// 1. Network -> `url_loader_` gets disconnected.
// 2. `url_loader_` gets cancelled by throttles.
// 3. `url_loader_` terminates itself.
if (IsRendererConnected()) {
if (!IsForwardURLLoadStarted()) {
// The loader is cancelled before this loader forwards anything to
// renderer. It should make an ateempt to forward any previous loads.
ForwardURLLoad();
// DO NOT touch any members after this line. `this` may be deleted.
return;
}
// Otherwise, let `ForwardURLLoad()` continue forwarding the rest.
return;
}
// We should let the renderer know it's closed by deleting `this`.
DeleteSelf();
// DO NOT touch any members after this line. `this` is already deleted.
}
// Browser -> Renderer connection
void KeepAliveURLLoader::ForwardingClient::OnDisconnected() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::ForwardingClient::OnDisconnected",
"request_id", request_id());
// Dropping the client as renderer is gone.
target_.reset();
if (!keep_alive_url_loader_->IsForwardURLLoadStarted() &&
!keep_alive_url_loader_->HasReceivedResponse()) {
// The renderer disconnects before this loader forwards anything to it.
// But the in-browser request processing may not complete yet.
// TODO(crbug.com/40259706): Ensure that attributionsrc response handling is
// taken over by browser.
return;
}
// Renderer disconnects in-between forwarding, no need to call
// `ForwardURLLoad()` anymore.
keep_alive_url_loader_->DeleteSelf();
// DO NOT touch any members after this line. `this` is already deleted.
}
// Browser <- Renderer connection.
void KeepAliveURLLoader::OnURLLoaderDisconnected() {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
TRACE_EVENT("loading", "KeepAliveURLLoader::OnURLLoaderDisconnected",
"request_id", request_id_);
if (!IsStarted()) {
// May be the last chance to start a deferred loader.
LogFetchLaterMetric(
FetchLaterBrowserMetricType::kStartedAfterInitiatorDisconnected);
Start();
}
// For other types of keepalive requests, this loader does not care about
// whether messages can be received from renderer or not.
// Prevents this loader from staying alive indefinitely.
if (!disconnected_loader_timer_.IsRunning()) {
disconnected_loader_timer_.Start(
FROM_HERE, GetDisconnectedKeepAliveURLLoaderTimeout(),
base::BindOnce(&KeepAliveURLLoader::OnDisconnectedLoaderTimerFired,
// `this` owns `disconnected_loader_timer_`.
base::Unretained(this)));
}
}
void KeepAliveURLLoader::OnDisconnectedLoaderTimerFired() {
if (IsFetchLater()) {
LogFetchLaterMetric(FetchLaterBrowserMetricType::kCancelledAfterTimeLimit);
}
DeleteSelf();
}
void KeepAliveURLLoader::Shutdown() {
base::UmaHistogramBoolean(
"FetchKeepAlive.Requests2.Shutdown.IsStarted.Browser", IsStarted());
if (!IsStarted()) {
CHECK(IsFetchLater());
LogFetchLaterMetric(FetchLaterBrowserMetricType::kStartedWhenShutdown);
// At this point, browser is shutting down, and renderer termination has not
// reached browser. It is the last chance to start loading the request from
// here.
Start();
}
}
bool KeepAliveURLLoader::IsFetchLater() const {
return base::FeatureList::IsEnabled(blink::features::kFetchLaterAPI) &&
resource_request_.is_fetch_later_api;
}
void KeepAliveURLLoader::SendNow() {
if (!IsFetchLater()) {
mojo::ReportBadMessage("Unexpected call to KeepAliveURLLoader::SendNow()");
return;
}
LogFetchLaterMetric(FetchLaterBrowserMetricType::kStartedByInitiator);
if (!IsStarted()) {
Start();
}
}
void KeepAliveURLLoader::Cancel() {
if (!IsFetchLater()) {
mojo::ReportBadMessage("Unexpected call to KeepAliveURLLoader::Cancel()");
return;
}
LogFetchLaterMetric(FetchLaterBrowserMetricType::kAbortedByInitiator);
DeleteSelf();
}
void KeepAliveURLLoader::DeleteSelf() {
CHECK(on_delete_callback_);
std::move(on_delete_callback_).Run();
}
void KeepAliveURLLoader::SetObserverForTesting(
scoped_refptr<TestObserver> observer) {
observer_for_testing_ = observer;
}
void KeepAliveURLLoader::LogFetchKeepAliveRequestMetric(
std::string_view request_state_name) {
if (IsFetchLater()) {
return;
}
auto resource_type =
static_cast<blink::mojom::ResourceType>(resource_request_.resource_type);
FetchKeepAliveRequestMetricType sample_type;
// See also blink::PopulateResourceRequest().
switch (resource_type) {
case blink::mojom::ResourceType::kXhr:
sample_type = FetchKeepAliveRequestMetricType::kFetch;
break;
// Includes BEACON/PING/ATTRIBUTION_SRC types
case blink::mojom::ResourceType::kPing:
sample_type = FetchKeepAliveRequestMetricType::kPing;
break;
case blink::mojom::ResourceType::kCspReport:
sample_type = FetchKeepAliveRequestMetricType::kReporting;
break;
case blink::mojom::ResourceType::kImage:
sample_type = FetchKeepAliveRequestMetricType::kBackgroundFetchIcon;
break;
case blink::mojom::ResourceType::kMainFrame:
case blink::mojom::ResourceType::kSubFrame:
case blink::mojom::ResourceType::kStylesheet:
case blink::mojom::ResourceType::kScript:
case blink::mojom::ResourceType::kFontResource:
case blink::mojom::ResourceType::kSubResource:
case blink::mojom::ResourceType::kObject:
case blink::mojom::ResourceType::kMedia:
case blink::mojom::ResourceType::kWorker:
case blink::mojom::ResourceType::kSharedWorker:
case blink::mojom::ResourceType::kPrefetch:
case blink::mojom::ResourceType::kFavicon:
case blink::mojom::ResourceType::kServiceWorker:
case blink::mojom::ResourceType::kPluginResource:
case blink::mojom::ResourceType::kNavigationPreloadMainFrame:
case blink::mojom::ResourceType::kNavigationPreloadSubFrame:
case blink::mojom::ResourceType::kJson:
NOTREACHED();
}
CHECK(request_state_name == "Total" || request_state_name == "Started" ||
request_state_name == "Succeeded" || request_state_name == "Failed");
base::UmaHistogramEnumeration(base::StrCat({"FetchKeepAlive.Requests2.",
request_state_name, ".Browser"}),
sample_type);
if (bool is_context_detached = !GetInitiator();
request_state_name == "Started" || request_state_name == "Succeeded") {
base::UmaHistogramBoolean(
base::StrCat({"FetchKeepAlive.Requests2.", request_state_name,
".IsContextDetached.Browser"}),
is_context_detached);
}
}
} // namespace content