/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=8 sts=2 et sw=2 tw=80: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "nsMixedContentBlocker.h" #include "nsContentPolicyUtils.h" #include "nsCSPContext.h" #include "nsThreadUtils.h" #include "nsINode.h" #include "nsCOMPtr.h" #include "nsDocShell.h" #include "nsIWebProgressListener.h" #include "nsContentUtils.h" #include "mozilla/dom/BrowsingContext.h" #include "mozilla/dom/WindowContext.h" #include "mozilla/dom/Document.h" #include "nsIChannel.h" #include "nsIParentChannel.h" #include "mozilla/Preferences.h" #include "nsIScriptObjectPrincipal.h" #include "nsIProtocolHandler.h" #include "nsCharSeparatedTokenizer.h" #include "nsISecureBrowserUI.h" #include "nsIWebNavigation.h" #include "nsLoadGroup.h" #include "nsIScriptError.h" #include "nsIURI.h" #include "nsIChannelEventSink.h" #include "nsNetUtil.h" #include "nsAsyncRedirectVerifyHelper.h" #include "mozilla/LoadInfo.h" #include "nsISiteSecurityService.h" #include "prnetdb.h" #include "nsQueryObject.h" #include "mozilla/BasePrincipal.h" #include "mozilla/Logging.h" #include "mozilla/StaticPrefs_dom.h" #include "mozilla/StaticPrefs_fission.h" #include "mozilla/StaticPrefs_security.h" #include "mozilla/Telemetry.h" #include "mozilla/dom/ContentChild.h" #include "mozilla/ipc/URIUtils.h" #include "mozilla/net/DNS.h" #include "mozilla/net/DocumentLoadListener.h" #include "mozilla/net/DocumentChannel.h" #include "mozilla/dom/nsHTTPSOnlyUtils.h" using namespace mozilla; using namespace mozilla::dom; static mozilla::LazyLogModule sMCBLog("MCBLog"); enum nsMixedContentBlockerMessageType { eBlocked = 0x00, eUserOverride = 0x01 }; // Allowlist of hostnames that should be considered secure contexts even when // served over http:// or ws:// nsCString* nsMixedContentBlocker::sSecurecontextAllowlist = nullptr; bool nsMixedContentBlocker::sSecurecontextAllowlistCached = false; enum MixedContentHSTSState { MCB_HSTS_PASSIVE_NO_HSTS = 0, MCB_HSTS_PASSIVE_WITH_HSTS = 1, MCB_HSTS_ACTIVE_NO_HSTS = 2, MCB_HSTS_ACTIVE_WITH_HSTS = 3 }; nsMixedContentBlocker::~nsMixedContentBlocker() = default; NS_IMPL_ISUPPORTS(nsMixedContentBlocker, nsIContentPolicy, nsIChannelEventSink) static void LogMixedContentMessage( MixedContentTypes aClassification, nsIURI* aContentLocation, uint64_t aInnerWindowID, nsMixedContentBlockerMessageType aMessageType, nsIURI* aRequestingLocation, const nsACString& aOverruleMessageLookUpKeyWithThis = ""_ns) { nsAutoCString messageCategory; uint32_t severityFlag; nsAutoCString messageLookupKey; if (aMessageType == eBlocked) { severityFlag = nsIScriptError::errorFlag; messageCategory.AssignLiteral("Mixed Content Blocker"); if (aClassification == eMixedDisplay) { messageLookupKey.AssignLiteral("BlockMixedDisplayContent"); } else { messageLookupKey.AssignLiteral("BlockMixedActiveContent"); } } else { severityFlag = nsIScriptError::warningFlag; messageCategory.AssignLiteral("Mixed Content Message"); if (aClassification == eMixedDisplay) { messageLookupKey.AssignLiteral("LoadingMixedDisplayContent2"); } else { messageLookupKey.AssignLiteral("LoadingMixedActiveContent2"); } } // if the callee explicitly wants to use a special message for this // console report, then we allow to overrule the default with the // explicitly provided one here. if (!aOverruleMessageLookUpKeyWithThis.IsEmpty()) { messageLookupKey = aOverruleMessageLookUpKeyWithThis; } nsAutoString localizedMsg; AutoTArray params; CopyUTF8toUTF16(aContentLocation->GetSpecOrDefault(), *params.AppendElement()); nsContentUtils::FormatLocalizedString(nsContentUtils::eSECURITY_PROPERTIES, messageLookupKey.get(), params, localizedMsg); nsContentUtils::ReportToConsoleByWindowID(localizedMsg, severityFlag, messageCategory, aInnerWindowID, aRequestingLocation); } /* nsIChannelEventSink implementation * This code is called when a request is redirected. * We check the channel associated with the new uri is allowed to load * in the current context */ NS_IMETHODIMP nsMixedContentBlocker::AsyncOnChannelRedirect( nsIChannel* aOldChannel, nsIChannel* aNewChannel, uint32_t aFlags, nsIAsyncVerifyRedirectCallback* aCallback) { mozilla::net::nsAsyncRedirectAutoCallback autoCallback(aCallback); if (!aOldChannel) { NS_ERROR("No channel when evaluating mixed content!"); return NS_ERROR_FAILURE; } // If we are in the parent process in e10s, we don't have access to the // document node, and hence ShouldLoad will fail when we try to get // the docShell. If that's the case, ignore mixed content checks // on redirects in the parent. Let the child check for mixed content. nsCOMPtr is_ipc_channel; NS_QueryNotificationCallbacks(aNewChannel, is_ipc_channel); RefPtr docListener = do_QueryObject(is_ipc_channel); if (is_ipc_channel && !docListener) { return NS_OK; } // Don't do these checks if we're switching from DocumentChannel // to a real channel. In that case, we should already have done // the checks in the parent process. AsyncOnChannelRedirect // isn't called in the content process if we switch process, // so checking here would just hide bugs in the process switch // cases. if (RefPtr docChannel = do_QueryObject(aOldChannel)) { return NS_OK; } nsresult rv; nsCOMPtr oldUri; rv = aOldChannel->GetURI(getter_AddRefs(oldUri)); NS_ENSURE_SUCCESS(rv, rv); nsCOMPtr newUri; rv = aNewChannel->GetURI(getter_AddRefs(newUri)); NS_ENSURE_SUCCESS(rv, rv); // Get the loading Info from the old channel nsCOMPtr loadInfo = aOldChannel->LoadInfo(); nsCOMPtr requestingPrincipal = loadInfo->GetLoadingPrincipal(); // Since we are calling shouldLoad() directly on redirects, we don't go // through the code in nsContentPolicyUtils::NS_CheckContentLoadPolicy(). // Hence, we have to duplicate parts of it here. if (requestingPrincipal) { // We check to see if the loadingPrincipal is systemPrincipal and return // early if it is if (requestingPrincipal->IsSystemPrincipal()) { return NS_OK; } } int16_t decision = REJECT_REQUEST; rv = ShouldLoad(newUri, loadInfo, &decision); if (NS_FAILED(rv)) { autoCallback.DontCallback(); aOldChannel->Cancel(NS_ERROR_DOM_BAD_URI); return NS_BINDING_FAILED; } // If the channel is about to load mixed content, abort the channel if (!NS_CP_ACCEPTED(decision)) { autoCallback.DontCallback(); aOldChannel->Cancel(NS_ERROR_DOM_BAD_URI); return NS_BINDING_FAILED; } return NS_OK; } /* This version of ShouldLoad() is non-static and called by the Content Policy * API and AsyncOnChannelRedirect(). See nsIContentPolicy::ShouldLoad() * for detailed description of the parameters. */ NS_IMETHODIMP nsMixedContentBlocker::ShouldLoad(nsIURI* aContentLocation, nsILoadInfo* aLoadInfo, int16_t* aDecision) { // We pass in false as the first parameter to ShouldLoad(), because the // callers of this method don't know whether the load went through cached // image redirects. This is handled by direct callers of the static // ShouldLoad. nsresult rv = ShouldLoad(false, // aHadInsecureImageRedirect aContentLocation, aLoadInfo, true, aDecision); if (*aDecision == nsIContentPolicy::REJECT_REQUEST) { NS_SetRequestBlockingReason(aLoadInfo, nsILoadInfo::BLOCKING_REASON_MIXED_BLOCKED); } return rv; } bool nsMixedContentBlocker::IsPotentiallyTrustworthyLoopbackHost( const nsACString& aAsciiHost) { if (mozilla::net::IsLoopbackHostname(aAsciiHost)) { return true; } using namespace mozilla::net; NetAddr addr; if (NS_FAILED(addr.InitFromString(aAsciiHost))) { return false; } // Step 4 of // https://w3c.github.io/webappsec-secure-contexts/#is-origin-trustworthy says // we should only consider [::1]/128 as a potentially trustworthy IPv6 // address, whereas for IPv4 127.0.0.1/8 are considered as potentially // trustworthy. return addr.IsLoopBackAddressWithoutIPv6Mapping(); } bool nsMixedContentBlocker::IsPotentiallyTrustworthyLoopbackURL(nsIURI* aURL) { if (!aURL) { return false; } nsAutoCString asciiHost; nsresult rv = aURL->GetAsciiHost(asciiHost); NS_ENSURE_SUCCESS(rv, false); return IsPotentiallyTrustworthyLoopbackHost(asciiHost); } /* Maybe we have a .onion URL. Treat it as trustworthy as well if * `dom.securecontext.allowlist_onions` is `true`. */ bool nsMixedContentBlocker::IsPotentiallyTrustworthyOnion(nsIURI* aURL) { if (!StaticPrefs::dom_securecontext_allowlist_onions()) { return false; } nsAutoCString host; nsresult rv = aURL->GetHost(host); NS_ENSURE_SUCCESS(rv, false); return StringEndsWith(host, ".onion"_ns); } // static void nsMixedContentBlocker::OnPrefChange(const char* aPref, void* aClosure) { MOZ_ASSERT(NS_IsMainThread()); MOZ_ASSERT(!strcmp(aPref, "dom.securecontext.allowlist")); Preferences::GetCString("dom.securecontext.allowlist", *sSecurecontextAllowlist); } // static void nsMixedContentBlocker::GetSecureContextAllowList(nsACString& aList) { MOZ_ASSERT(NS_IsMainThread()); if (!sSecurecontextAllowlistCached) { MOZ_ASSERT(!sSecurecontextAllowlist); sSecurecontextAllowlistCached = true; sSecurecontextAllowlist = new nsCString(); Preferences::RegisterCallbackAndCall(OnPrefChange, "dom.securecontext.allowlist"); } aList = *sSecurecontextAllowlist; } // static void nsMixedContentBlocker::Shutdown() { if (sSecurecontextAllowlist) { delete sSecurecontextAllowlist; sSecurecontextAllowlist = nullptr; } } bool nsMixedContentBlocker::IsPotentiallyTrustworthyOrigin(nsIURI* aURI) { // The following implements: // https://w3c.github.io/webappsec-secure-contexts/#is-origin-trustworthy nsAutoCString scheme; nsresult rv = aURI->GetScheme(scheme); if (NS_FAILED(rv)) { return false; } // Blobs are expected to inherit their principal so we don't expect to have // a content principal with scheme 'blob' here. We can't assert that though // since someone could mess with a non-blob URI to give it that scheme. NS_WARNING_ASSERTION(!scheme.EqualsLiteral("blob"), "IsOriginPotentiallyTrustworthy ignoring blob scheme"); // According to the specification, the user agent may choose to extend the // trust to other, vendor-specific URL schemes. We use this for "resource:", // which is technically a substituting protocol handler that is not limited to // local resource mapping, but in practice is never mapped remotely as this // would violate assumptions a lot of code makes. // We use nsIProtocolHandler flags to determine which protocols we consider a // priori authenticated. bool aPrioriAuthenticated = false; if (NS_FAILED(NS_URIChainHasFlags( aURI, nsIProtocolHandler::URI_IS_POTENTIALLY_TRUSTWORTHY, &aPrioriAuthenticated))) { return false; } if (aPrioriAuthenticated) { return true; } nsAutoCString host; rv = aURI->GetHost(host); if (NS_FAILED(rv)) { return false; } if (IsPotentiallyTrustworthyLoopbackURL(aURI)) { return true; } // If a host is not considered secure according to the default algorithm, then // check to see if it has been allowlisted by the user. We only apply this // allowlist for network resources, i.e., those with scheme "http" or "ws". // The pref should contain a comma-separated list of hostnames. if (!scheme.EqualsLiteral("http") && !scheme.EqualsLiteral("ws")) { return false; } nsAutoCString allowlist; GetSecureContextAllowList(allowlist); for (const nsACString& allowedHost : nsCCharSeparatedTokenizer(allowlist, ',').ToRange()) { if (host.Equals(allowedHost)) { return true; } } // Maybe we have a .onion URL. Treat it as trustworthy as well if // `dom.securecontext.allowlist_onions` is `true`. if (nsMixedContentBlocker::IsPotentiallyTrustworthyOnion(aURI)) { return true; } return false; } /* static */ bool nsMixedContentBlocker::IsUpgradableContentType(nsContentPolicyType aType, bool aConsiderPrefs) { MOZ_ASSERT(NS_IsMainThread()); if (aConsiderPrefs && !StaticPrefs::security_mixed_content_upgrade_display_content()) { return false; } switch (aType) { case nsIContentPolicy::TYPE_INTERNAL_IMAGE: case nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD: return !aConsiderPrefs || StaticPrefs:: security_mixed_content_upgrade_display_content_image(); case nsIContentPolicy::TYPE_INTERNAL_AUDIO: return !aConsiderPrefs || StaticPrefs:: security_mixed_content_upgrade_display_content_audio(); case nsIContentPolicy::TYPE_INTERNAL_VIDEO: return !aConsiderPrefs || StaticPrefs:: security_mixed_content_upgrade_display_content_video(); default: return false; } } /* * Return the URI of the precusor principal or the URI of aPrincipal if there is * no precursor URI. */ static already_AddRefed GetPrincipalURIOrPrecursorPrincipalURI( nsIPrincipal* aPrincipal) { nsCOMPtr precursorPrincipal = aPrincipal->GetPrecursorPrincipal(); #ifdef DEBUG if (precursorPrincipal) { MOZ_ASSERT(aPrincipal->GetIsNullPrincipal(), "Only Null Principals should have a Precursor Principal"); } #endif return precursorPrincipal ? precursorPrincipal->GetURI() : aPrincipal->GetURI(); } /* Static version of ShouldLoad() that contains all the Mixed Content Blocker * logic. Called from non-static ShouldLoad(). */ nsresult nsMixedContentBlocker::ShouldLoad(bool aHadInsecureImageRedirect, nsIURI* aContentLocation, nsILoadInfo* aLoadInfo, bool aReportError, int16_t* aDecision) { // Asserting that we are on the main thread here and hence do not have to lock // and unlock security.mixed_content.block_active_content and // security.mixed_content.block_display_content before reading/writing to // them. MOZ_ASSERT(NS_IsMainThread()); if (MOZ_UNLIKELY(MOZ_LOG_TEST(sMCBLog, LogLevel::Verbose))) { nsAutoCString asciiUrl; aContentLocation->GetAsciiSpec(asciiUrl); MOZ_LOG(sMCBLog, LogLevel::Verbose, ("shouldLoad:")); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - contentLocation: %s", asciiUrl.get())); } nsContentPolicyType internalContentType = aLoadInfo->InternalContentPolicyType(); nsCOMPtr loadingPrincipal = aLoadInfo->GetLoadingPrincipal(); nsCOMPtr triggeringPrincipal = aLoadInfo->TriggeringPrincipal(); if (MOZ_UNLIKELY(MOZ_LOG_TEST(sMCBLog, LogLevel::Verbose))) { MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - internalContentPolicyType: %s", NS_CP_ContentTypeName(internalContentType))); if (loadingPrincipal != nullptr) { nsAutoCString loadingPrincipalAsciiUrl; loadingPrincipal->GetAsciiSpec(loadingPrincipalAsciiUrl); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - loadingPrincipal: %s", loadingPrincipalAsciiUrl.get())); } else { MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - loadingPrincipal: (nullptr)")); } nsAutoCString triggeringPrincipalAsciiUrl; triggeringPrincipal->GetAsciiSpec(triggeringPrincipalAsciiUrl); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - triggeringPrincipal: %s", triggeringPrincipalAsciiUrl.get())); } RefPtr requestingWindow = WindowContext::GetById(aLoadInfo->GetInnerWindowID()); bool isPreload = nsContentUtils::IsPreloadType(internalContentType); // The content policy type that we receive may be an internal type for // scripts. Let's remember if we have seen a worker type, and reset it to the // external type in all cases right now. bool isWorkerType = internalContentType == nsIContentPolicy::TYPE_INTERNAL_WORKER || internalContentType == nsIContentPolicy::TYPE_INTERNAL_WORKER_STATIC_MODULE || internalContentType == nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER || internalContentType == nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER; ExtContentPolicyType contentType = nsContentUtils::InternalContentPolicyTypeToExternal(internalContentType); // Assume active (high risk) content and blocked by default MixedContentTypes classification = eMixedScript; // Make decision to block/reject by default *aDecision = REJECT_REQUEST; // Notes on non-obvious decisions: // // TYPE_DTD: A DTD can contain entity definitions that expand to scripts. // // TYPE_FONT: The TrueType hinting mechanism is basically a scripting // language that gets interpreted by the operating system's font rasterizer. // Mixed content web fonts are relatively uncommon, and we can can fall back // to built-in fonts with minimal disruption in almost all cases. // // TYPE_OBJECT_SUBREQUEST could actually be either active content (e.g. a // script that a plugin will execute) or display content (e.g. Flash video // content). Until we have a way to determine active vs passive content // from plugin requests (bug 836352), we will treat this as passive content. // This is to prevent false positives from causing users to become // desensitized to the mixed content blocker. // // TYPE_CSP_REPORT: High-risk because they directly leak information about // the content of the page, and because blocking them does not have any // negative effect on the page loading. // // TYPE_PING: Ping requests are POSTS, not GETs like images and media. // Also, PING requests have no bearing on the rendering or operation of // the page when used as designed, so even though they are lower risk than // scripts, blocking them is basically risk-free as far as compatibility is // concerned. // // TYPE_STYLESHEET: XSLT stylesheets can insert scripts. CSS positioning // and other advanced CSS features can possibly be exploited to cause // spoofing attacks (e.g. make a "grant permission" button look like a // "refuse permission" button). // // TYPE_BEACON: Beacon requests are similar to TYPE_PING, and are blocked by // default. // // TYPE_WEBSOCKET: The Websockets API requires browsers to // reject mixed-content websockets: "If secure is false but the origin of // the entry script has a scheme component that is itself a secure protocol, // e.g. HTTPS, then throw a SecurityError exception." We already block mixed // content websockets within the websockets implementation, so we don't need // to do any blocking here, nor do we need to provide a way to undo or // override the blocking. Websockets without TLS are very flaky anyway in the // face of many HTTP-aware proxies. Compared to passive content, there is // additional risk that the script using WebSockets will disclose sensitive // information from the HTTPS page and/or eval (directly or indirectly) // received data. // // TYPE_XMLHTTPREQUEST: XHR requires either same origin or CORS, so most // mixed-content XHR will already be blocked by that check. This will also // block HTTPS-to-HTTP XHR with CORS. The same security concerns mentioned // above for WebSockets apply to XHR, and XHR should have the same security // properties as WebSockets w.r.t. mixed content. XHR's handling of redirects // amplifies these concerns. // // TYPE_PROXIED_WEBRTC_MEDIA: Ordinarily, webrtc uses low-level sockets for // peer-to-peer media, which bypasses this code entirely. However, when a // web proxy is being used, the TCP and TLS webrtc connections are routed // through the web proxy (using HTTP CONNECT), which causes these connections // to be checked. We just skip mixed content blocking in that case. switch (contentType) { // The top-level document cannot be mixed content by definition case ExtContentPolicy::TYPE_DOCUMENT: *aDecision = ACCEPT; return NS_OK; // Creating insecure websocket connections in a secure page is blocked // already in the websocket constructor. We don't need to check the blocking // here and we don't want to un-block case ExtContentPolicy::TYPE_WEBSOCKET: *aDecision = ACCEPT; return NS_OK; // TYPE_SAVEAS_DOWNLOAD: Save-link-as feature is used to download a // resource // without involving a docShell. This kind of loading must be // allowed, if not disabled in the preferences. // Creating insecure connections for a save-as link download is // acceptable. This download is completely disconnected from the docShell, // but still using the same loading principal. case ExtContentPolicy::TYPE_SAVEAS_DOWNLOAD: *aDecision = ACCEPT; return NS_OK; break; // It does not make sense to subject webrtc media connections to mixed // content blocking, since those connections are peer-to-peer and will // therefore almost never match the origin. case ExtContentPolicy::TYPE_PROXIED_WEBRTC_MEDIA: *aDecision = ACCEPT; return NS_OK; // Static display content is considered moderate risk for mixed content so // these will be blocked according to the mixed display preference case ExtContentPolicy::TYPE_IMAGE: case ExtContentPolicy::TYPE_MEDIA: classification = eMixedDisplay; break; case ExtContentPolicy::TYPE_OBJECT_SUBREQUEST: if (StaticPrefs::security_mixed_content_block_object_subrequest()) { classification = eMixedScript; } else { classification = eMixedDisplay; } break; // Active content (or content with a low value/risk-of-blocking ratio) // that has been explicitly evaluated; listed here for documentation // purposes and to avoid the assertion and warning for the default case. case ExtContentPolicy::TYPE_BEACON: case ExtContentPolicy::TYPE_CSP_REPORT: case ExtContentPolicy::TYPE_DTD: case ExtContentPolicy::TYPE_FETCH: case ExtContentPolicy::TYPE_FONT: case ExtContentPolicy::TYPE_UA_FONT: case ExtContentPolicy::TYPE_IMAGESET: case ExtContentPolicy::TYPE_OBJECT: case ExtContentPolicy::TYPE_SCRIPT: case ExtContentPolicy::TYPE_STYLESHEET: case ExtContentPolicy::TYPE_SUBDOCUMENT: case ExtContentPolicy::TYPE_PING: case ExtContentPolicy::TYPE_WEB_MANIFEST: case ExtContentPolicy::TYPE_XMLHTTPREQUEST: case ExtContentPolicy::TYPE_XSLT: case ExtContentPolicy::TYPE_OTHER: case ExtContentPolicy::TYPE_SPECULATIVE: case ExtContentPolicy::TYPE_WEB_TRANSPORT: case ExtContentPolicy::TYPE_WEB_IDENTITY: break; case ExtContentPolicy::TYPE_INVALID: MOZ_ASSERT(false, "Mixed content of unknown type"); // Do not add default: so that compilers can catch the missing case. } // Make sure to get the URI the load started with. No need to check // outer schemes because all the wrapping pseudo protocols inherit the // security properties of the actual network request represented // by the innerMost URL. nsCOMPtr innerContentLocation = NS_GetInnermostURI(aContentLocation); if (!innerContentLocation) { NS_ERROR("Can't get innerURI from aContentLocation"); *aDecision = REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because the innermost " "URI could not be " "retrieved")); return NS_OK; } // TYPE_IMAGE redirects are cached based on the original URI, not the final // destination and hence cache hits for images may not have the correct // innerContentLocation. Check if the cached hit went through an http // redirect, and if it did, we can't treat this as a secure subresource. if (!aHadInsecureImageRedirect && URISafeToBeLoadedInSecureContext(innerContentLocation)) { *aDecision = ACCEPT; return NS_OK; } /* * Most likely aLoadingPrincipal reflects the security context of the owning * document for this mixed content check. There are cases where that is not * true, hence we have to we process requests in the following order: * 1) If the load is triggered by the SystemPrincipal, we allow the load. * Content scripts from addon code do provide aTriggeringPrincipal, which * is an ExpandedPrincipal. If encountered, we allow the load. * 2) If aLoadingPrincipal does not yield to a requestingLocation, then we * fall back to querying the requestingLocation from aTriggeringPrincipal. * 3) If we still end up not having a requestingLocation, we reject the load. */ // 1) Check if the load was triggered by the system (SystemPrincipal) or // a content script from addons code (ExpandedPrincipal) in which case the // load is not subject to mixed content blocking. if (triggeringPrincipal) { if (triggeringPrincipal->IsSystemPrincipal()) { *aDecision = ACCEPT; return NS_OK; } nsCOMPtr expanded = do_QueryInterface(triggeringPrincipal); if (expanded) { *aDecision = ACCEPT; return NS_OK; } } // 2) If aLoadingPrincipal does not provide a requestingLocation, then // we fall back to to querying the requestingLocation from // aTriggeringPrincipal. nsCOMPtr requestingLocation = GetPrincipalURIOrPrecursorPrincipalURI(loadingPrincipal); if (!requestingLocation) { requestingLocation = GetPrincipalURIOrPrecursorPrincipalURI(triggeringPrincipal); } // 3) Giving up. We still don't have a requesting location, therefore we can't // tell if this is a mixed content load. Deny to be safe. if (!requestingLocation) { *aDecision = REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because no requesting " "location could be " "gathered.")); return NS_OK; } // Check the parent scheme. If it is not an HTTPS page then mixed content // restrictions do not apply. nsCOMPtr innerRequestingLocation = NS_GetInnermostURI(requestingLocation); if (!innerRequestingLocation) { NS_ERROR("Can't get innerURI from requestingLocation"); *aDecision = REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because the innermost " "URI of the " "requesting location could be gathered.")); return NS_OK; } bool parentIsHttps = innerRequestingLocation->SchemeIs("https"); if (!parentIsHttps) { *aDecision = ACCEPT; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be allowed because the requesting " "location is not using " "HTTPS.")); return NS_OK; } // Disallow mixed content loads for workers, shared workers and service // workers. if (isWorkerType) { // For workers, we can assume that we're mixed content at this point, since // the parent is https, and the protocol associated with // innerContentLocation doesn't map to the secure URI flags checked above. // Assert this for sanity's sake #ifdef DEBUG bool isHttpsScheme = innerContentLocation->SchemeIs("https"); MOZ_ASSERT(!isHttpsScheme); #endif *aDecision = REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected, trying to load a worker " "from an insecure origin.")); return NS_OK; } bool isHttpScheme = innerContentLocation->SchemeIs("http"); if (isHttpScheme && IsPotentiallyTrustworthyOrigin(innerContentLocation)) { *aDecision = ACCEPT; return NS_OK; } // Check if https-only mode upgrades this later anyway if (nsHTTPSOnlyUtils::IsSafeToAcceptCORSOrMixedContent(aLoadInfo)) { *aDecision = ACCEPT; return NS_OK; } // The page might have set the CSP directive 'upgrade-insecure-requests'. In // such a case allow the http: load to succeed with the promise that the // channel will get upgraded to https before fetching any data from the // netwerk. Please see: nsHttpChannel::Connect() // // Please note that the CSP directive 'upgrade-insecure-requests' only applies // to http: and ws: (for websockets). Websockets are not subject to mixed // content blocking since insecure websockets are not allowed within secure // pages. Hence, we only have to check against http: here. Skip mixed content // blocking if the subresource load uses http: and the CSP directive // 'upgrade-insecure-requests' is present on the page. // Carve-out: if we're in the parent and we're loading media, e.g. through // webbrowserpersist, don't reject it if we can't find a docshell. if (XRE_IsParentProcess() && !requestingWindow && (contentType == ExtContentPolicy::TYPE_IMAGE || contentType == ExtContentPolicy::TYPE_MEDIA)) { *aDecision = ACCEPT; return NS_OK; } // Otherwise, we must have a window NS_ENSURE_TRUE(requestingWindow, NS_OK); if (isHttpScheme && aLoadInfo->GetUpgradeInsecureRequests()) { *aDecision = ACCEPT; return NS_OK; } // Allow http: mixed content if we are choosing to upgrade them when the // pref "security.mixed_content.upgrade_display_content" is true. // This behaves like GetUpgradeInsecureRequests above in that the channel will // be upgraded to https before fetching any data from the netwerk. if (isHttpScheme) { bool isUpgradableContentType = IsUpgradableContentType(internalContentType, /* aConsiderPrefs */ true); if (isUpgradableContentType) { *aDecision = ACCEPT; return NS_OK; } } // The page might have set the CSP directive 'block-all-mixed-content' which // should block not only active mixed content loads but in fact all mixed // content loads, see https://www.w3.org/TR/mixed-content/#strict-checking // Block all non secure loads in case the CSP directive is present. Please // note that at this point we already know, based on |schemeSecure| that the // load is not secure, so we can bail out early at this point. if (aLoadInfo->GetBlockAllMixedContent()) { // log a message to the console before returning. nsAutoCString spec; nsresult rv = aContentLocation->GetSpec(spec); NS_ENSURE_SUCCESS(rv, rv); AutoTArray params; CopyUTF8toUTF16(spec, *params.AppendElement()); CSP_LogLocalizedStr("blockAllMixedContent", params, u""_ns, // aSourceFile u""_ns, // aScriptSample 0, // aLineNumber 1, // aColumnNumber nsIScriptError::errorFlag, "blockAllMixedContent"_ns, requestingWindow->Id(), !!aLoadInfo->GetOriginAttributes().mPrivateBrowsingId); *aDecision = REJECT_REQUEST; MOZ_LOG( sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because the CSP directive " "'block-all-mixed-content' was set while trying to load data from " "a non-secure origin.")); return NS_OK; } // Determine if the rootDoc is https and if the user decided to allow Mixed // Content WindowContext* topWC = requestingWindow->TopWindowContext(); bool rootHasSecureConnection = topWC->GetIsSecure(); bool allowMixedContent = topWC->GetAllowMixedContent(); // When navigating an iframe, the iframe may be https but its parents may not // be. Check the parents to see if any of them are https. If none of the // parents are https, allow the load. if (contentType == ExtContentPolicyType::TYPE_SUBDOCUMENT && !rootHasSecureConnection && !parentIsHttps) { bool httpsParentExists = false; RefPtr curWindow = requestingWindow; while (!httpsParentExists && curWindow) { httpsParentExists = curWindow->GetIsSecure(); curWindow = curWindow->GetParentWindowContext(); } if (!httpsParentExists) { *aDecision = nsIContentPolicy::ACCEPT; return NS_OK; } } OriginAttributes originAttributes; if (loadingPrincipal) { originAttributes = loadingPrincipal->OriginAttributesRef(); } else if (triggeringPrincipal) { originAttributes = triggeringPrincipal->OriginAttributesRef(); } // At this point we know that the request is mixed content, and the only // question is whether we block it. Record telemetry at this point as to // whether HSTS would have fixed things by making the content location // into an HTTPS URL. // // Note that we count this for redirects as well as primary requests. This // will cause some degree of double-counting, especially when mixed content // is not blocked (e.g., for images). For more detail, see: // https://bugzilla.mozilla.org/show_bug.cgi?id=1198572#c19 // // We do not count requests aHadInsecureImageRedirect=true, since these are // just an artifact of the image caching system. bool active = (classification == eMixedScript); if (!aHadInsecureImageRedirect) { if (XRE_IsParentProcess()) { AccumulateMixedContentHSTS(innerContentLocation, active, originAttributes); } else { // Ask the parent process to do the same call mozilla::dom::ContentChild* cc = mozilla::dom::ContentChild::GetSingleton(); if (cc) { cc->SendAccumulateMixedContentHSTS(innerContentLocation, active, originAttributes); } } } // set hasMixedContentObjectSubrequest on this object if necessary if (contentType == ExtContentPolicyType::TYPE_OBJECT_SUBREQUEST && aReportError) { if (!StaticPrefs::security_mixed_content_block_object_subrequest()) { nsAutoCString messageLookUpKey( "LoadingMixedDisplayObjectSubrequestDeprecation"); LogMixedContentMessage(classification, aContentLocation, topWC->Id(), eUserOverride, requestingLocation, messageLookUpKey); } } uint32_t newState = 0; // If the content is display content, and the pref says display content should // be blocked, block it. if (classification == eMixedDisplay) { if (!StaticPrefs::security_mixed_content_block_display_content() || allowMixedContent) { *aDecision = nsIContentPolicy::ACCEPT; // User has overriden the pref and the root is not https; // mixed display content was allowed on an https subframe. newState |= nsIWebProgressListener::STATE_LOADED_MIXED_DISPLAY_CONTENT; } else { *aDecision = nsIContentPolicy::REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because the content is " "display " "content (blocked by pref " "security.mixed_content.block_display_content).")); newState |= nsIWebProgressListener::STATE_BLOCKED_MIXED_DISPLAY_CONTENT; } } else { MOZ_ASSERT(classification == eMixedScript); // If the content is active content, and the pref says active content should // be blocked, block it unless the user has choosen to override the pref if (!StaticPrefs::security_mixed_content_block_active_content() || allowMixedContent) { *aDecision = nsIContentPolicy::ACCEPT; // User has already overriden the pref and the root is not https; // mixed active content was allowed on an https subframe. newState |= nsIWebProgressListener::STATE_LOADED_MIXED_ACTIVE_CONTENT; } else { // User has not overriden the pref by Disabling protection. Reject the // request and update the security state. *aDecision = nsIContentPolicy::REJECT_REQUEST; MOZ_LOG(sMCBLog, LogLevel::Verbose, (" -> decision: Request will be rejected because the content is " "active " "content (blocked by pref " "security.mixed_content.block_active_content).")); // The user has not overriden the pref, so make sure they still have an // option by calling nativeDocShell which will invoke the doorhanger newState |= nsIWebProgressListener::STATE_BLOCKED_MIXED_ACTIVE_CONTENT; } } // To avoid duplicate errors on the console, we do not report blocked // preloads to the console. if (!isPreload && aReportError) { LogMixedContentMessage(classification, aContentLocation, topWC->Id(), (*aDecision == nsIContentPolicy::REJECT_REQUEST) ? eBlocked : eUserOverride, requestingLocation); } // Notify the top WindowContext of the flags we've computed, and it // will handle updating any relevant security UI. topWC->AddSecurityState(newState); return NS_OK; } bool nsMixedContentBlocker::URISafeToBeLoadedInSecureContext(nsIURI* aURI) { /* Returns a bool if the URI can be loaded as a sub resource safely. * * Check Protocol Flags to determine if scheme is safe to load: * URI_DOES_NOT_RETURN_DATA - e.g. * "mailto" * URI_IS_LOCAL_RESOURCE - e.g. * "data", * "resource", * "moz-icon" * URI_INHERITS_SECURITY_CONTEXT - e.g. * "javascript" * URI_IS_POTENTIALLY_TRUSTWORTHY - e.g. * "https", * "moz-safe-about" * */ bool schemeLocal = false; bool schemeNoReturnData = false; bool schemeInherits = false; bool schemeSecure = false; if (NS_FAILED(NS_URIChainHasFlags( aURI, nsIProtocolHandler::URI_IS_LOCAL_RESOURCE, &schemeLocal)) || NS_FAILED(NS_URIChainHasFlags( aURI, nsIProtocolHandler::URI_DOES_NOT_RETURN_DATA, &schemeNoReturnData)) || NS_FAILED(NS_URIChainHasFlags( aURI, nsIProtocolHandler::URI_INHERITS_SECURITY_CONTEXT, &schemeInherits)) || NS_FAILED(NS_URIChainHasFlags( aURI, nsIProtocolHandler::URI_IS_POTENTIALLY_TRUSTWORTHY, &schemeSecure))) { return false; } MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - URISafeToBeLoadedInSecureContext:")); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - schemeLocal: %i", schemeLocal)); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - schemeNoReturnData: %i", schemeNoReturnData)); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - schemeInherits: %i", schemeInherits)); MOZ_LOG(sMCBLog, LogLevel::Verbose, (" - schemeSecure: %i", schemeSecure)); return (schemeLocal || schemeNoReturnData || schemeInherits || schemeSecure); } NS_IMETHODIMP nsMixedContentBlocker::ShouldProcess(nsIURI* aContentLocation, nsILoadInfo* aLoadInfo, int16_t* aDecision) { if (!aContentLocation) { // aContentLocation may be null when a plugin is loading without an // associated URI resource if (aLoadInfo->GetExternalContentPolicyType() == ExtContentPolicyType::TYPE_OBJECT) { *aDecision = ACCEPT; return NS_OK; } NS_SetRequestBlockingReason(aLoadInfo, nsILoadInfo::BLOCKING_REASON_MIXED_BLOCKED); *aDecision = REJECT_REQUEST; return NS_ERROR_FAILURE; } return ShouldLoad(aContentLocation, aLoadInfo, aDecision); } // Record information on when HSTS would have made mixed content not mixed // content (regardless of whether it was actually blocked) void nsMixedContentBlocker::AccumulateMixedContentHSTS( nsIURI* aURI, bool aActive, const OriginAttributes& aOriginAttributes) { // This method must only be called in the parent, because // nsSiteSecurityService is only available in the parent if (!XRE_IsParentProcess()) { MOZ_ASSERT(false); return; } bool hsts; nsresult rv; nsCOMPtr sss = do_GetService(NS_SSSERVICE_CONTRACTID, &rv); if (NS_FAILED(rv)) { return; } rv = sss->IsSecureURI(aURI, aOriginAttributes, &hsts); if (NS_FAILED(rv)) { return; } // states: would upgrade, would prime, hsts info cached // active, passive // if (!aActive) { if (!hsts) { Telemetry::Accumulate(Telemetry::MIXED_CONTENT_HSTS, MCB_HSTS_PASSIVE_NO_HSTS); } else { Telemetry::Accumulate(Telemetry::MIXED_CONTENT_HSTS, MCB_HSTS_PASSIVE_WITH_HSTS); } } else { if (!hsts) { Telemetry::Accumulate(Telemetry::MIXED_CONTENT_HSTS, MCB_HSTS_ACTIVE_NO_HSTS); } else { Telemetry::Accumulate(Telemetry::MIXED_CONTENT_HSTS, MCB_HSTS_ACTIVE_WITH_HSTS); } } }