diff options
Diffstat (limited to 'js/xpconnect/loader/mozJSSubScriptLoader.cpp')
| -rw-r--r-- | js/xpconnect/loader/mozJSSubScriptLoader.cpp | 476 |
1 files changed, 476 insertions, 0 deletions
diff --git a/js/xpconnect/loader/mozJSSubScriptLoader.cpp b/js/xpconnect/loader/mozJSSubScriptLoader.cpp new file mode 100644 index 0000000000..33192bff29 --- /dev/null +++ b/js/xpconnect/loader/mozJSSubScriptLoader.cpp @@ -0,0 +1,476 @@ +/* -*- 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 "mozJSSubScriptLoader.h" +#include "js/experimental/JSStencil.h" +#include "mozJSModuleLoader.h" +#include "mozJSLoaderUtils.h" + +#include "nsIURI.h" +#include "nsIIOService.h" +#include "nsIChannel.h" +#include "nsIInputStream.h" +#include "nsNetCID.h" +#include "nsNetUtil.h" + +#include "jsapi.h" +#include "jsfriendapi.h" +#include "xpcprivate.h" // xpc::OptionsBase +#include "js/CompilationAndEvaluation.h" // JS::Compile +#include "js/CompileOptions.h" // JS::ReadOnlyCompileOptions, JS::DecodeOptions +#include "js/friend/JSMEnvironment.h" // JS::ExecuteInJSMEnvironment, JS::IsJSMEnvironment +#include "js/SourceText.h" // JS::Source{Ownership,Text} +#include "js/Wrapper.h" + +#include "mozilla/ContentPrincipal.h" +#include "mozilla/dom/ScriptLoader.h" +#include "mozilla/ProfilerLabels.h" +#include "mozilla/ProfilerMarkers.h" +#include "mozilla/ScriptPreloader.h" +#include "mozilla/SystemPrincipal.h" +#include "mozilla/scache/StartupCache.h" +#include "mozilla/scache/StartupCacheUtils.h" +#include "mozilla/Unused.h" +#include "mozilla/Utf8.h" // mozilla::Utf8Unit +#include "nsContentUtils.h" +#include "nsString.h" + +using namespace mozilla::scache; +using namespace JS; +using namespace xpc; +using namespace mozilla; +using namespace mozilla::dom; + +class MOZ_STACK_CLASS LoadSubScriptOptions : public OptionsBase { + public: + explicit LoadSubScriptOptions(JSContext* cx = xpc_GetSafeJSContext(), + JSObject* options = nullptr) + : OptionsBase(cx, options), + target(cx), + ignoreCache(false), + wantReturnValue(false) {} + + virtual bool Parse() override { + return ParseObject("target", &target) && + ParseBoolean("ignoreCache", &ignoreCache) && + ParseBoolean("wantReturnValue", &wantReturnValue); + } + + RootedObject target; + bool ignoreCache; + bool wantReturnValue; +}; + +/* load() error msgs, XXX localize? */ +#define LOAD_ERROR_NOSERVICE "Error creating IO Service." +#define LOAD_ERROR_NOURI "Error creating URI (invalid URL scheme?)" +#define LOAD_ERROR_NOSCHEME "Failed to get URI scheme. This is bad." +#define LOAD_ERROR_URI_NOT_LOCAL "Trying to load a non-local URI." +#define LOAD_ERROR_NOSTREAM "Error opening input stream (invalid filename?)" +#define LOAD_ERROR_NOCONTENT "ContentLength not available (not a local URL?)" +#define LOAD_ERROR_BADCHARSET "Error converting to specified charset" +#define LOAD_ERROR_NOSPEC "Failed to get URI spec. This is bad." +#define LOAD_ERROR_CONTENTTOOBIG "ContentLength is too large" + +mozJSSubScriptLoader::mozJSSubScriptLoader() = default; + +mozJSSubScriptLoader::~mozJSSubScriptLoader() = default; + +NS_IMPL_ISUPPORTS(mozJSSubScriptLoader, mozIJSSubScriptLoader) + +#define JSSUB_CACHE_PREFIX(aScopeType, aCompilationTarget) \ + "jssubloader/" aScopeType "/" aCompilationTarget + +static void SubscriptCachePath(JSContext* cx, nsIURI* uri, + JS::HandleObject targetObj, + nsACString& cachePath) { + // StartupCache must distinguish between non-syntactic vs global when + // computing the cache key. + if (!JS_IsGlobalObject(targetObj)) { + PathifyURI(JSSUB_CACHE_PREFIX("non-syntactic", "script"), uri, cachePath); + } else { + PathifyURI(JSSUB_CACHE_PREFIX("global", "script"), uri, cachePath); + } +} + +static void ReportError(JSContext* cx, const nsACString& msg) { + NS_ConvertUTF8toUTF16 ucMsg(msg); + + RootedValue exn(cx); + if (xpc::NonVoidStringToJsval(cx, ucMsg, &exn)) { + JS_SetPendingException(cx, exn); + } +} + +static void ReportError(JSContext* cx, const char* origMsg, nsIURI* uri) { + if (!uri) { + ReportError(cx, nsDependentCString(origMsg)); + return; + } + + nsAutoCString spec; + nsresult rv = uri->GetSpec(spec); + if (NS_FAILED(rv)) { + spec.AssignLiteral("(unknown)"); + } + + nsAutoCString msg(origMsg); + msg.AppendLiteral(": "); + msg.Append(spec); + ReportError(cx, msg); +} + +static bool EvalStencil(JSContext* cx, HandleObject targetObj, + HandleObject loadScope, MutableHandleValue retval, + nsIURI* uri, bool storeIntoStartupCache, + bool storeIntoPreloadCache, JS::Stencil* stencil) { + MOZ_ASSERT(!js::IsWrapper(targetObj)); + + JS::InstantiateOptions options; + JS::RootedScript script(cx, + JS::InstantiateGlobalStencil(cx, options, stencil)); + if (!script) { + return false; + } + + if (JS_IsGlobalObject(targetObj)) { + if (!JS_ExecuteScript(cx, script, retval)) { + return false; + } + } else if (JS::IsJSMEnvironment(targetObj)) { + if (!JS::ExecuteInJSMEnvironment(cx, script, targetObj)) { + return false; + } + retval.setUndefined(); + } else { + JS::RootedObjectVector envChain(cx); + if (!envChain.append(targetObj)) { + return false; + } + if (!loadScope) { + // A null loadScope means we are cross-realm. In this case, we should + // check the target isn't in the JSM loader shared-global or we will + // contaminate all JSMs in the realm. + // + // NOTE: If loadScope is already a shared-global JSM, we can't + // determine which JSM the target belongs to and have to assume it + // is in our JSM. +#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED + JSObject* targetGlobal = JS::GetNonCCWObjectGlobal(targetObj); + MOZ_DIAGNOSTIC_ASSERT( + !mozJSModuleLoader::Get()->IsLoaderGlobal(targetGlobal), + "Don't load subscript into target in a shared-global JSM"); +#endif + if (!JS_ExecuteScript(cx, envChain, script, retval)) { + return false; + } + } else if (JS_IsGlobalObject(loadScope)) { + if (!JS_ExecuteScript(cx, envChain, script, retval)) { + return false; + } + } else { + MOZ_ASSERT(JS::IsJSMEnvironment(loadScope)); + if (!JS::ExecuteInJSMEnvironment(cx, script, loadScope, envChain)) { + return false; + } + retval.setUndefined(); + } + } + + JSAutoRealm rar(cx, targetObj); + if (!JS_WrapValue(cx, retval)) { + return false; + } + + if (script && (storeIntoStartupCache || storeIntoPreloadCache)) { + nsAutoCString cachePath; + SubscriptCachePath(cx, uri, targetObj, cachePath); + + nsCString uriStr; + if (storeIntoPreloadCache && NS_SUCCEEDED(uri->GetSpec(uriStr))) { + ScriptPreloader::GetSingleton().NoteStencil(uriStr, cachePath, stencil); + } + + if (storeIntoStartupCache) { + JSAutoRealm ar(cx, script); + WriteCachedStencil(StartupCache::GetSingleton(), cachePath, cx, stencil); + } + } + + return true; +} + +bool mozJSSubScriptLoader::ReadStencil( + JS::Stencil** stencilOut, nsIURI* uri, JSContext* cx, + const JS::ReadOnlyCompileOptions& options, nsIIOService* serv, + bool useCompilationScope) { + // We create a channel and call SetContentType, to avoid expensive MIME type + // lookups (bug 632490). + nsCOMPtr<nsIChannel> chan; + nsCOMPtr<nsIInputStream> instream; + nsresult rv; + rv = NS_NewChannel(getter_AddRefs(chan), uri, + nsContentUtils::GetSystemPrincipal(), + nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL, + nsIContentPolicy::TYPE_OTHER, + nullptr, // nsICookieJarSettings + nullptr, // PerformanceStorage + nullptr, // aLoadGroup + nullptr, // aCallbacks + nsIRequest::LOAD_NORMAL, serv); + + if (NS_SUCCEEDED(rv)) { + chan->SetContentType("application/javascript"_ns); + rv = chan->Open(getter_AddRefs(instream)); + } + + if (NS_FAILED(rv)) { + ReportError(cx, LOAD_ERROR_NOSTREAM, uri); + return false; + } + + int64_t len = -1; + + rv = chan->GetContentLength(&len); + if (NS_FAILED(rv)) { + ReportError(cx, LOAD_ERROR_NOCONTENT, uri); + return false; + } + + if (len > INT32_MAX) { + ReportError(cx, LOAD_ERROR_CONTENTTOOBIG, uri); + return false; + } + + nsCString buf; + rv = NS_ReadInputStreamToString(instream, buf, len); + NS_ENSURE_SUCCESS(rv, false); + + if (len < 0) { + len = buf.Length(); + } + + Maybe<JSAutoRealm> ar; + + // Note that when using the ScriptPreloader cache with loadSubScript, there + // will be a side-effect of keeping the global that the script was compiled + // for alive. See note above in EvalScript(). + // + // This will compile the script in XPConnect compilation scope. When the + // script is evaluated, it will be cloned into the target scope to be + // executed, avoiding leaks on the first session when we don't have a + // startup cache. + if (useCompilationScope) { + ar.emplace(cx, xpc::CompilationScope()); + } + + JS::SourceText<Utf8Unit> srcBuf; + if (!srcBuf.init(cx, buf.get(), len, JS::SourceOwnership::Borrowed)) { + return false; + } + + RefPtr<JS::Stencil> stencil = + JS::CompileGlobalScriptToStencil(cx, options, srcBuf); + stencil.forget(stencilOut); + return *stencilOut; +} + +NS_IMETHODIMP +mozJSSubScriptLoader::LoadSubScript(const nsAString& url, HandleValue target, + JSContext* cx, MutableHandleValue retval) { + /* + * Loads a local url, referring to UTF-8-encoded data, and evals it into the + * current cx. Synchronous. ChromeUtils.compileScript() should be used for + * async loads. + * url: The url to load. Must be local so that it can be loaded + * synchronously. + * targetObj: Optional object to eval the script onto (defaults to context + * global) + * returns: Whatever jsval the script pointed to by the url returns. + * Should ONLY (O N L Y !) be called from JavaScript code. + */ + LoadSubScriptOptions options(cx); + options.target = target.isObject() ? &target.toObject() : nullptr; + return DoLoadSubScriptWithOptions(url, options, cx, retval); +} + +NS_IMETHODIMP +mozJSSubScriptLoader::LoadSubScriptWithOptions(const nsAString& url, + HandleValue optionsVal, + JSContext* cx, + MutableHandleValue retval) { + if (!optionsVal.isObject()) { + return NS_ERROR_INVALID_ARG; + } + + LoadSubScriptOptions options(cx, &optionsVal.toObject()); + if (!options.Parse()) { + return NS_ERROR_INVALID_ARG; + } + + return DoLoadSubScriptWithOptions(url, options, cx, retval); +} + +nsresult mozJSSubScriptLoader::DoLoadSubScriptWithOptions( + const nsAString& url, LoadSubScriptOptions& options, JSContext* cx, + MutableHandleValue retval) { + nsresult rv = NS_OK; + RootedObject targetObj(cx); + RootedObject loadScope(cx); + mozJSModuleLoader* loader = mozJSModuleLoader::Get(); + loader->FindTargetObject(cx, &loadScope); + + if (options.target) { + targetObj = options.target; + } else { + targetObj = loadScope; + } + + targetObj = JS_FindCompilationScope(cx, targetObj); + if (!targetObj || !loadScope) { + return NS_ERROR_FAILURE; + } + + MOZ_ASSERT(!js::IsWrapper(targetObj), "JS_FindCompilationScope must unwrap"); + + if (js::GetNonCCWObjectRealm(loadScope) != + js::GetNonCCWObjectRealm(targetObj)) { + loadScope = nullptr; + } + + /* load up the url. From here on, failures are reflected as ``custom'' + * js exceptions */ + nsCOMPtr<nsIURI> uri; + nsAutoCString uriStr; + nsAutoCString scheme; + + // Figure out who's calling us + JS::AutoFilename filename; + if (!JS::DescribeScriptedCaller(cx, &filename)) { + // No scripted frame means we don't know who's calling, bail. + return NS_ERROR_FAILURE; + } + + JSAutoRealm ar(cx, targetObj); + + nsCOMPtr<nsIIOService> serv = do_GetService(NS_IOSERVICE_CONTRACTID); + if (!serv) { + ReportError(cx, nsLiteralCString(LOAD_ERROR_NOSERVICE)); + return NS_OK; + } + + NS_LossyConvertUTF16toASCII asciiUrl(url); + const nsDependentCSubstring profilerUrl = + Substring(asciiUrl, 0, std::min(size_t(128), asciiUrl.Length())); + AUTO_PROFILER_LABEL_DYNAMIC_NSCSTRING_NONSENSITIVE( + "mozJSSubScriptLoader::DoLoadSubScriptWithOptions", OTHER, profilerUrl); + AUTO_PROFILER_MARKER_TEXT("SubScript", JS, + MarkerOptions(MarkerStack::Capture(), + MarkerInnerWindowIdFromJSContext(cx)), + profilerUrl); + + // Make sure to explicitly create the URI, since we'll need the + // canonicalized spec. + rv = NS_NewURI(getter_AddRefs(uri), asciiUrl); + if (NS_FAILED(rv)) { + ReportError(cx, nsLiteralCString(LOAD_ERROR_NOURI)); + return NS_OK; + } + + rv = uri->GetSpec(uriStr); + if (NS_FAILED(rv)) { + ReportError(cx, nsLiteralCString(LOAD_ERROR_NOSPEC)); + return NS_OK; + } + + rv = uri->GetScheme(scheme); + if (NS_FAILED(rv)) { + ReportError(cx, LOAD_ERROR_NOSCHEME, uri); + return NS_OK; + } + + // Suppress caching if we're compiling as content or if we're loading a + // blob: URI. + bool useCompilationScope = false; + auto* principal = BasePrincipal::Cast(GetObjectPrincipal(targetObj)); + bool isSystem = principal->Is<SystemPrincipal>(); + if (!isSystem && principal->Is<ContentPrincipal>()) { + nsAutoCString scheme; + principal->GetScheme(scheme); + + // We want to enable caching for scripts with Activity Stream's + // codebase URLs. + if (scheme.EqualsLiteral("about")) { + nsAutoCString filePath; + principal->GetFilePath(filePath); + + useCompilationScope = filePath.EqualsLiteral("home") || + filePath.EqualsLiteral("newtab") || + filePath.EqualsLiteral("welcome"); + isSystem = true; + } + } + bool ignoreCache = + options.ignoreCache || !isSystem || scheme.EqualsLiteral("blob"); + + StartupCache* cache = ignoreCache ? nullptr : StartupCache::GetSingleton(); + + nsAutoCString cachePath; + SubscriptCachePath(cx, uri, targetObj, cachePath); + + JS::DecodeOptions decodeOptions; + ScriptPreloader::FillDecodeOptionsForCachedStencil(decodeOptions); + + RefPtr<JS::Stencil> stencil; + if (!options.ignoreCache) { + if (!options.wantReturnValue) { + // NOTE: If we need the return value, we cannot use ScriptPreloader. + stencil = ScriptPreloader::GetSingleton().GetCachedStencil( + cx, decodeOptions, cachePath); + } + if (!stencil && cache) { + rv = ReadCachedStencil(cache, cachePath, cx, decodeOptions, + getter_AddRefs(stencil)); + if (NS_FAILED(rv) || !stencil) { + JS_ClearPendingException(cx); + } + } + } + + bool storeIntoStartupCache = false; + if (!stencil) { + // Store into startup cache only when the script isn't come from any cache. + storeIntoStartupCache = cache; + + JS::CompileOptions compileOptions(cx); + ScriptPreloader::FillCompileOptionsForCachedStencil(compileOptions); + compileOptions.setFileAndLine(uriStr.get(), 1); + compileOptions.setNonSyntacticScope(!JS_IsGlobalObject(targetObj)); + + if (options.wantReturnValue) { + compileOptions.setNoScriptRval(false); + } + + if (!ReadStencil(getter_AddRefs(stencil), uri, cx, compileOptions, serv, + useCompilationScope)) { + return NS_OK; + } + +#ifdef DEBUG + // The above shouldn't touch any options for instantiation. + JS::InstantiateOptions instantiateOptions(compileOptions); + instantiateOptions.assertDefault(); +#endif + } + + // As a policy choice, we don't store scripts that want return values + // into the preload cache. + bool storeIntoPreloadCache = !ignoreCache && !options.wantReturnValue; + + Unused << EvalStencil(cx, targetObj, loadScope, retval, uri, + storeIntoStartupCache, storeIntoPreloadCache, stencil); + return NS_OK; +} |