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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "mozilla/net/UrlClassifierCommon.h"
#include "mozilla/AntiTrackingUtils.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/Components.h"
#include "mozilla/ContentBlockingAllowList.h"
#include "mozilla/ContentBlockingNotifier.h"
#include "mozilla/dom/WindowGlobalParent.h"
#include "mozilla/net/HttpBaseChannel.h"
#include "mozilla/net/UrlClassifierFeatureFactory.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/StaticPrefs_privacy.h"
#include "mozilla/StaticPrefs_channelclassifier.h"
#include "mozilla/StaticPrefs_security.h"
#include "mozIThirdPartyUtil.h"
#include "nsContentUtils.h"
#include "nsIChannel.h"
#include "nsIClassifiedChannel.h"
#include "mozilla/dom/Document.h"
#include "nsIDocShell.h"
#include "nsIHttpChannel.h"
#include "nsIHttpChannelInternal.h"
#include "nsIParentChannel.h"
#include "nsIScriptError.h"
#include "nsIWebProgressListener.h"
#include "nsNetUtil.h"
#include "nsQueryObject.h"
#include "nsReadableUtils.h"
namespace mozilla {
namespace net {
const nsCString::size_type UrlClassifierCommon::sMaxSpecLength = 128;
// MOZ_LOG=nsChannelClassifier:5
LazyLogModule UrlClassifierCommon::sLog("nsChannelClassifier");
LazyLogModule UrlClassifierCommon::sLogLeak("nsChannelClassifierLeak");
/* static */
bool UrlClassifierCommon::AddonMayLoad(nsIChannel* aChannel, nsIURI* aURI) {
nsCOMPtr<nsILoadInfo> channelLoadInfo = aChannel->LoadInfo();
// loadingPrincipal is used here to ensure we are loading into an
// addon principal. This allows an addon, with explicit permission, to
// call out to API endpoints that may otherwise get blocked.
nsIPrincipal* loadingPrincipal = channelLoadInfo->GetLoadingPrincipal();
if (!loadingPrincipal) {
return false;
}
return BasePrincipal::Cast(loadingPrincipal)->AddonAllowsLoad(aURI, true);
}
/* static */
bool UrlClassifierCommon::ShouldEnableProtectionForChannel(
nsIChannel* aChannel) {
MOZ_ASSERT(aChannel);
nsCOMPtr<nsIURI> chanURI;
nsresult rv = aChannel->GetURI(getter_AddRefs(chanURI));
if (NS_WARN_IF(NS_FAILED(rv))) {
return false;
}
if (UrlClassifierCommon::AddonMayLoad(aChannel, chanURI)) {
return false;
}
nsCOMPtr<nsIURI> topWinURI;
nsCOMPtr<nsIHttpChannelInternal> channel = do_QueryInterface(aChannel);
if (NS_WARN_IF(!channel)) {
return false;
}
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
MOZ_ASSERT(loadInfo);
auto policyType = loadInfo->GetExternalContentPolicyType();
if (policyType == ExtContentPolicy::TYPE_DOCUMENT) {
UC_LOG(
("UrlClassifierCommon::ShouldEnableProtectionForChannel - "
"skipping top-level load for channel %p",
aChannel));
return false;
}
// Tracking protection will be enabled so return without updating
// the security state. If any channels are subsequently cancelled
// (page elements blocked) the state will be then updated.
return true;
}
/* static */
nsresult UrlClassifierCommon::SetTrackingInfo(
nsIChannel* aChannel, const nsTArray<nsCString>& aLists,
const nsTArray<nsCString>& aFullHashes) {
NS_ENSURE_ARG(!aLists.IsEmpty());
// Can be called in EITHER the parent or child process.
nsresult rv;
nsCOMPtr<nsIClassifiedChannel> classifiedChannel =
do_QueryInterface(aChannel, &rv);
NS_ENSURE_SUCCESS(rv, rv);
if (classifiedChannel) {
classifiedChannel->SetMatchedTrackingInfo(aLists, aFullHashes);
}
nsCOMPtr<nsIParentChannel> parentChannel;
NS_QueryNotificationCallbacks(aChannel, parentChannel);
if (parentChannel) {
// This channel is a parent-process proxy for a child process request.
// Tell the child process channel to do this as well.
// TODO: We can remove the code sending the IPC to content to update
// tracking info once we move the ContentBlockingLog into the parent.
nsAutoCString strLists, strHashes;
TablesToString(aLists, strLists);
TablesToString(aFullHashes, strHashes);
parentChannel->SetClassifierMatchedTrackingInfo(strLists, strHashes);
}
return NS_OK;
}
/* static */
nsresult UrlClassifierCommon::SetBlockedContent(nsIChannel* channel,
nsresult aErrorCode,
const nsACString& aList,
const nsACString& aProvider,
const nsACString& aFullHash) {
NS_ENSURE_ARG(!aList.IsEmpty());
switch (aErrorCode) {
case NS_ERROR_MALWARE_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_MALWARE_URI);
break;
case NS_ERROR_PHISHING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_PHISHING_URI);
break;
case NS_ERROR_UNWANTED_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_UNWANTED_URI);
break;
case NS_ERROR_TRACKING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_TRACKING_URI);
break;
case NS_ERROR_BLOCKED_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_BLOCKED_URI);
break;
case NS_ERROR_HARMFUL_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_HARMFUL_URI);
break;
case NS_ERROR_CRYPTOMINING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_CRYPTOMINING_URI);
break;
case NS_ERROR_FINGERPRINTING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_FINGERPRINTING_URI);
break;
case NS_ERROR_SOCIALTRACKING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_SOCIALTRACKING_URI);
break;
case NS_ERROR_EMAILTRACKING_URI:
NS_SetRequestBlockingReason(
channel, nsILoadInfo::BLOCKING_REASON_CLASSIFY_EMAILTRACKING_URI);
break;
default:
MOZ_CRASH(
"Missing nsILoadInfo::BLOCKING_REASON* for the classification error");
break;
}
// Can be called in EITHER the parent or child process.
nsresult rv;
nsCOMPtr<nsIClassifiedChannel> classifiedChannel =
do_QueryInterface(channel, &rv);
NS_ENSURE_SUCCESS(rv, rv);
if (classifiedChannel) {
classifiedChannel->SetMatchedInfo(aList, aProvider, aFullHash);
}
if (XRE_IsParentProcess()) {
nsCOMPtr<nsIParentChannel> parentChannel;
NS_QueryNotificationCallbacks(channel, parentChannel);
if (parentChannel) {
// This channel is a parent-process proxy for a child process request.
// Tell the child process channel to do this as well.
// TODO: We can remove the code sending the IPC to content to update
// matched info once we move the ContentBlockingLog into the parent.
parentChannel->SetClassifierMatchedInfo(aList, aProvider, aFullHash);
}
unsigned state =
UrlClassifierFeatureFactory::GetClassifierBlockingEventCode(aErrorCode);
if (!state) {
state = nsIWebProgressListener::STATE_BLOCKED_UNSAFE_CONTENT;
}
ContentBlockingNotifier::OnEvent(channel, state);
return NS_OK;
}
// TODO: ReportToConsole is called in the child process,
// If nsContentUtils::ReportToConsole is not fission compatiable(cannot report
// to correct top-level window), we need to do this in the parent process
// instead (find the top-level window in the parent and send an IPC to child
// processes to report console).
nsCOMPtr<mozIThirdPartyUtil> thirdPartyUtil =
components::ThirdPartyUtil::Service();
if (NS_WARN_IF(!thirdPartyUtil)) {
return NS_OK;
}
nsCOMPtr<nsIURI> uriBeingLoaded =
AntiTrackingUtils::MaybeGetDocumentURIBeingLoaded(channel);
nsCOMPtr<mozIDOMWindowProxy> win;
rv = thirdPartyUtil->GetTopWindowForChannel(channel, uriBeingLoaded,
getter_AddRefs(win));
NS_ENSURE_SUCCESS(rv, NS_OK);
auto* pwin = nsPIDOMWindowOuter::From(win);
nsCOMPtr<nsIDocShell> docShell = pwin->GetDocShell();
if (!docShell) {
return NS_OK;
}
RefPtr<dom::Document> doc = docShell->GetDocument();
NS_ENSURE_TRUE(doc, NS_OK);
// Log a warning to the web console.
nsCOMPtr<nsIURI> uri;
channel->GetURI(getter_AddRefs(uri));
AutoTArray<nsString, 1> params;
CopyUTF8toUTF16(uri->GetSpecOrDefault(), *params.AppendElement());
const char* message;
nsCString category;
if (UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode(aErrorCode)) {
message = UrlClassifierFeatureFactory::
ClassifierBlockingErrorCodeToConsoleMessage(aErrorCode, category);
} else {
message = "UnsafeUriBlocked";
category = "Safe Browsing"_ns;
}
nsContentUtils::ReportToConsole(nsIScriptError::warningFlag, category, doc,
nsContentUtils::eNECKO_PROPERTIES, message,
params);
return NS_OK;
}
/* static */
nsresult UrlClassifierCommon::GetTopWindowURI(nsIChannel* aChannel,
nsIURI** aURI) {
MOZ_ASSERT(XRE_IsParentProcess());
MOZ_ASSERT(aChannel);
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
MOZ_ASSERT(loadInfo);
RefPtr<dom::BrowsingContext> browsingContext;
nsresult rv =
loadInfo->GetTargetBrowsingContext(getter_AddRefs(browsingContext));
if (NS_WARN_IF(NS_FAILED(rv)) || !browsingContext) {
return NS_ERROR_FAILURE;
}
dom::CanonicalBrowsingContext* top = browsingContext->Canonical()->Top();
dom::WindowGlobalParent* wgp = top->GetCurrentWindowGlobal();
if (!wgp) {
return NS_ERROR_FAILURE;
}
RefPtr<nsIURI> uri = wgp->GetDocumentURI();
if (!uri) {
return NS_ERROR_FAILURE;
}
uri.forget(aURI);
return NS_OK;
}
/* static */
nsresult UrlClassifierCommon::CreatePairwiseEntityListURI(nsIChannel* aChannel,
nsIURI** aURI) {
MOZ_ASSERT(aChannel);
MOZ_ASSERT(aURI);
nsresult rv;
nsCOMPtr<nsIHttpChannelInternal> chan = do_QueryInterface(aChannel, &rv);
NS_ENSURE_SUCCESS(rv, rv);
if (!chan) {
return NS_ERROR_FAILURE;
}
nsCOMPtr<nsIURI> topWinURI;
rv =
UrlClassifierCommon::GetTopWindowURI(aChannel, getter_AddRefs(topWinURI));
if (NS_FAILED(rv) || !topWinURI) {
// SharedWorker and ServiceWorker don't have an associated window, use
// client's URI instead.
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
MOZ_ASSERT(loadInfo);
Maybe<dom::ClientInfo> clientInfo = loadInfo->GetClientInfo();
if (clientInfo.isSome()) {
if ((clientInfo->Type() == dom::ClientType::Sharedworker) ||
(clientInfo->Type() == dom::ClientType::Serviceworker)) {
UC_LOG(
("UrlClassifierCommon::CreatePairwiseEntityListURI - "
"channel %p initiated by worker, get uri from client",
aChannel));
auto clientPrincipalOrErr = clientInfo->GetPrincipal();
if (clientPrincipalOrErr.isOk()) {
nsCOMPtr<nsIPrincipal> principal = clientPrincipalOrErr.unwrap();
if (principal) {
auto* basePrin = BasePrincipal::Cast(principal);
rv = basePrin->GetURI(getter_AddRefs(topWinURI));
Unused << NS_WARN_IF(NS_FAILED(rv));
}
}
}
}
if (!topWinURI) {
UC_LOG(
("UrlClassifierCommon::CreatePairwiseEntityListURI - "
"no top-level window associated with channel %p, "
"get uri from loading principal",
aChannel));
nsCOMPtr<nsIPrincipal> principal = loadInfo->GetLoadingPrincipal();
if (principal) {
auto* basePrin = BasePrincipal::Cast(principal);
rv = basePrin->GetURI(getter_AddRefs(topWinURI));
Unused << NS_WARN_IF(NS_FAILED(rv));
}
}
}
if (!topWinURI) {
UC_LOG(
("UrlClassifierCommon::CreatePairwiseEntityListURI - "
"fail to get top-level window uri for channel %p",
aChannel));
// Return success because we want to continue to look up even without
// whitelist.
return NS_OK;
}
nsCOMPtr<nsIScriptSecurityManager> securityManager =
do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIPrincipal> chanPrincipal;
rv = securityManager->GetChannelURIPrincipal(aChannel,
getter_AddRefs(chanPrincipal));
NS_ENSURE_SUCCESS(rv, rv);
// Craft a entitylist URL like "toplevel.page/?resource=third.party.domain"
nsAutoCString pageHostname, resourceDomain;
rv = topWinURI->GetHost(pageHostname);
if (NS_FAILED(rv)) {
// When the top-level page doesn't support GetHost, for example, about:home,
// we don't return an error here; instead, we return success to make sure
// that the lookup process calling this API continues to run.
if (UC_LOG_ENABLED()) {
nsCString topWinSpec =
topWinURI ? topWinURI->GetSpecOrDefault() : "(null)"_ns;
topWinSpec.Truncate(
std::min(topWinSpec.Length(), UrlClassifierCommon::sMaxSpecLength));
UC_LOG(
("UrlClassifierCommon::CreatePairwiseEntityListURI - "
"cannot get host from the top-level uri %s of channel %p",
topWinSpec.get(), aChannel));
}
return NS_OK;
}
rv = chanPrincipal->GetBaseDomain(resourceDomain);
NS_ENSURE_SUCCESS(rv, rv);
nsAutoCString entitylistEntry =
"http://"_ns + pageHostname + "/?resource="_ns + resourceDomain;
UC_LOG(
("UrlClassifierCommon::CreatePairwiseEntityListURI - looking for %s in "
"the entitylist on channel %p",
entitylistEntry.get(), aChannel));
nsCOMPtr<nsIURI> entitylistURI;
rv = NS_NewURI(getter_AddRefs(entitylistURI), entitylistEntry);
if (NS_FAILED(rv)) {
return rv;
}
entitylistURI.forget(aURI);
return NS_OK;
}
namespace {
void LowerPriorityHelper(nsIChannel* aChannel) {
MOZ_ASSERT(aChannel);
bool isBlockingResource = false;
nsCOMPtr<nsIClassOfService> cos(do_QueryInterface(aChannel));
if (cos) {
if (StaticPrefs::network_http_tailing_enabled()) {
uint32_t cosFlags = 0;
cos->GetClassFlags(&cosFlags);
isBlockingResource =
cosFlags & (nsIClassOfService::UrgentStart |
nsIClassOfService::Leader | nsIClassOfService::Unblocked);
// Requests not allowed to be tailed are usually those with higher
// prioritization. That overweights being a tracker: don't throttle
// them when not in background.
if (!(cosFlags & nsIClassOfService::TailForbidden)) {
cos->AddClassFlags(nsIClassOfService::Throttleable);
}
} else {
// Yes, we even don't want to evaluate the isBlockingResource when tailing
cos->AddClassFlags(nsIClassOfService::Throttleable);
}
}
if (!isBlockingResource) {
nsCOMPtr<nsISupportsPriority> p = do_QueryInterface(aChannel);
if (p) {
UC_LOG(
("UrlClassifierCommon::LowerPriorityHelper - "
"setting PRIORITY_LOWEST for channel %p",
aChannel));
p->SetPriority(nsISupportsPriority::PRIORITY_LOWEST);
}
}
}
} // namespace
// static
void UrlClassifierCommon::SetClassificationFlagsHelper(
nsIChannel* aChannel, uint32_t aClassificationFlags, bool aIsThirdParty) {
MOZ_ASSERT(aChannel);
nsCOMPtr<nsIParentChannel> parentChannel;
NS_QueryNotificationCallbacks(aChannel, parentChannel);
if (parentChannel) {
// This channel is a parent-process proxy for a child process
// request. We should notify the child process as well.
parentChannel->NotifyClassificationFlags(aClassificationFlags,
aIsThirdParty);
}
RefPtr<HttpBaseChannel> httpChannel = do_QueryObject(aChannel);
if (httpChannel) {
httpChannel->AddClassificationFlags(aClassificationFlags, aIsThirdParty);
}
}
// static
void UrlClassifierCommon::AnnotateChannel(nsIChannel* aChannel,
uint32_t aClassificationFlags,
uint32_t aLoadingState) {
MOZ_ASSERT(XRE_IsParentProcess());
MOZ_ASSERT(aChannel);
nsCOMPtr<nsIURI> chanURI;
nsresult rv = aChannel->GetURI(getter_AddRefs(chanURI));
if (NS_WARN_IF(NS_FAILED(rv))) {
return;
}
bool isThirdPartyWithTopLevelWinURI =
AntiTrackingUtils::IsThirdPartyChannel(aChannel);
SetClassificationFlagsHelper(aChannel, aClassificationFlags,
isThirdPartyWithTopLevelWinURI);
// We consider valid tracking flags (based on the current strict vs basic list
// prefs) and cryptomining (which is not considered as tracking).
bool validClassificationFlags =
IsTrackingClassificationFlag(aClassificationFlags,
NS_UsePrivateBrowsing(aChannel)) ||
IsCryptominingClassificationFlag(aClassificationFlags,
NS_UsePrivateBrowsing(aChannel));
if (validClassificationFlags && isThirdPartyWithTopLevelWinURI) {
ContentBlockingNotifier::OnEvent(aChannel, aLoadingState);
}
if (isThirdPartyWithTopLevelWinURI &&
StaticPrefs::privacy_trackingprotection_lower_network_priority()) {
LowerPriorityHelper(aChannel);
}
}
// static
bool UrlClassifierCommon::IsAllowListed(nsIChannel* aChannel) {
nsCOMPtr<nsIHttpChannelInternal> channel = do_QueryInterface(aChannel);
if (NS_WARN_IF(!channel)) {
return false;
}
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
bool isAllowListed = false;
if (StaticPrefs::channelclassifier_allowlist_example()) {
UC_LOG(
("UrlClassifierCommon::IsAllowListed - "
"check allowlisting test domain on channel %p",
aChannel));
nsCOMPtr<nsIIOService> ios = components::IO::Service();
if (NS_WARN_IF(!ios)) {
return false;
}
nsCOMPtr<nsIURI> uri;
nullptr, getter_AddRefs(uri));
if (NS_WARN_IF(NS_FAILED(rv))) {
return false;
}
nsCOMPtr<nsIPrincipal> cbAllowListPrincipal =
BasePrincipal::CreateContentPrincipal(uri,
loadInfo->GetOriginAttributes());
rv = ContentBlockingAllowList::Check(
cbAllowListPrincipal, NS_UsePrivateBrowsing(aChannel), isAllowListed);
if (NS_WARN_IF(NS_FAILED(rv))) {
return false;
}
} else {
nsCOMPtr<nsICookieJarSettings> cookieJarSettings;
MOZ_ALWAYS_SUCCEEDS(
loadInfo->GetCookieJarSettings(getter_AddRefs(cookieJarSettings)));
isAllowListed = cookieJarSettings->GetIsOnContentBlockingAllowList();
}
if (isAllowListed) {
UC_LOG(("UrlClassifierCommon::IsAllowListed - user override on channel %p",
aChannel));
}
return isAllowListed;
}
// static
bool UrlClassifierCommon::IsTrackingClassificationFlag(uint32_t aFlag,
bool aIsPrivate) {
bool isLevel2ListEnabled =
aIsPrivate
? StaticPrefs::privacy_annotate_channels_strict_list_pbmode_enabled()
: StaticPrefs::privacy_annotate_channels_strict_list_enabled();
if (isLevel2ListEnabled &&
(aFlag & nsIClassifiedChannel::ClassificationFlags::
CLASSIFIED_ANY_STRICT_TRACKING)) {
return true;
}
if (StaticPrefs::privacy_socialtracking_block_cookies_enabled() &&
IsSocialTrackingClassificationFlag(aFlag)) {
return true;
}
return (
aFlag &
nsIClassifiedChannel::ClassificationFlags::CLASSIFIED_ANY_BASIC_TRACKING);
}
// static
bool UrlClassifierCommon::IsSocialTrackingClassificationFlag(uint32_t aFlag) {
return (aFlag & nsIClassifiedChannel::ClassificationFlags::
CLASSIFIED_ANY_SOCIAL_TRACKING) != 0;
}
// static
bool UrlClassifierCommon::IsCryptominingClassificationFlag(uint32_t aFlag,
bool aIsPrivate) {
if (aFlag &
nsIClassifiedChannel::ClassificationFlags::CLASSIFIED_CRYPTOMINING) {
return true;
}
bool isLevel2ListEnabled =
aIsPrivate
? StaticPrefs::privacy_annotate_channels_strict_list_pbmode_enabled()
: StaticPrefs::privacy_annotate_channels_strict_list_enabled();
if (isLevel2ListEnabled &&
(aFlag & nsIClassifiedChannel::ClassificationFlags::
CLASSIFIED_CRYPTOMINING_CONTENT)) {
return true;
}
return false;
}
void UrlClassifierCommon::TablesToString(const nsTArray<nsCString>& aList,
nsACString& aString) {
// Truncate and append rather than assigning because that's more efficient if
// aString is an nsAutoCString.
aString.Truncate();
StringJoinAppend(aString, ","_ns, aList);
}
uint32_t UrlClassifierCommon::TablesToClassificationFlags(
const nsTArray<nsCString>& aList,
const std::vector<ClassificationData>& aData, uint32_t aDefaultFlag) {
uint32_t flags = 0;
for (const nsCString& table : aList) {
flags |= TableToClassificationFlag(table, aData);
}
if (flags == 0) {
flags |= aDefaultFlag;
}
return flags;
}
uint32_t UrlClassifierCommon::TableToClassificationFlag(
const nsACString& aTable, const std::vector<ClassificationData>& aData) {
for (const ClassificationData& data : aData) {
if (StringBeginsWith(aTable, data.mPrefix)) {
return data.mFlag;
}
}
return 0;
}
/* static */
bool UrlClassifierCommon::IsPassiveContent(nsIChannel* aChannel) {
MOZ_ASSERT(aChannel);
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
ExtContentPolicyType contentType = loadInfo->GetExternalContentPolicyType();
// Return true if aChannel is loading passive display content, as
// defined by the mixed content blocker.
return contentType == ExtContentPolicy::TYPE_IMAGE ||
contentType == ExtContentPolicy::TYPE_MEDIA ||
(contentType == ExtContentPolicy::TYPE_OBJECT_SUBREQUEST &&
!StaticPrefs::security_mixed_content_block_object_subrequest());
}
} // namespace net
} // namespace mozilla