Bug 1391158: Optimize checkLoadURL for the common case of extension URLs. r=mixedpuppy

MozReview-Commit-ID: KGFFcHxQSvZ

--HG--
extra : rebase_source : f4b62ad095077a65e11c6b8354ce54fa2d2ff252

toolkit/components/extensions/Extension.jsm

@@ -821,7 +821,8 @@ this.Extension = class extends ExtensionData {
 
     this.id = addonData.id;
     this.version = addonData.version;
-    this.baseURI = Services.io.newURI(this.getURL("")).QueryInterface(Ci.nsIURL);
+    this.baseURL = this.getURL("");
+    this.baseURI = Services.io.newURI(this.baseURL).QueryInterface(Ci.nsIURL);
     this.principal = this.createPrincipal();
     this.views = new Set();
     this._backgroundPageFrameLoader = null;
@@ -943,7 +944,17 @@ this.Extension = class extends ExtensionData {
     let uri = Services.io.newURI(url);
 
     let common = this.baseURI.getCommonBaseSpec(uri);
-    return common == this.baseURI.spec;
+    return common == this.baseURL;
+  }
+
+  checkLoadURL(url, options = {}) {
+    // As an optimization, f the URL starts with the extension's base URL,
+    // don't do any further checks. It's always allowed to load it.
+    if (url.startsWith(this.baseURL)) {
+      return true;
+    }
+
+    return ExtensionUtils.checkLoadURL(url, this.principal, options);
   }
 
   async promiseLocales(locale) {

toolkit/components/extensions/ExtensionChild.jsm

@@ -511,6 +511,7 @@ class BrowserExtensionContent extends EventEmitter {
     this.localeData = new LocaleData(data.localeData);
 
     this.manifest = data.manifest;
+    this.baseURL = data.baseURL;
     this.baseURI = Services.io.newURI(data.baseURL);
 
     // Only used in addon processes.

toolkit/components/extensions/ExtensionCommon.jsm

@@ -271,27 +271,13 @@ class BaseContext {
   }
 
   checkLoadURL(url, options = {}) {
-    let ssm = Services.scriptSecurityManager;
-
-    let flags = ssm.STANDARD;
-    if (!options.allowScript) {
-      flags |= ssm.DISALLOW_SCRIPT;
-    }
-    if (!options.allowInheritsPrincipal) {
-      flags |= ssm.DISALLOW_INHERIT_PRINCIPAL;
-    }
-    if (options.dontReportErrors) {
-      flags |= ssm.DONT_REPORT_ERRORS;
+    // As an optimization, f the URL starts with the extension's base URL,
+    // don't do any further checks. It's always allowed to load it.
+    if (url.startsWith(this.extension.baseURL)) {
+      return true;
     }
 
-    try {
-      ssm.checkLoadURIWithPrincipal(this.principal,
-                                    Services.io.newURI(url),
-                                    flags);
-    } catch (e) {
-      return false;
-    }
-    return true;
+    return ExtensionUtils.checkLoadURL(url, this.principal, options);
   }
 
   /**

toolkit/components/extensions/ExtensionParent.jsm

@@ -1292,7 +1292,7 @@ let IconDetails = {
           // relative paths. We currently accept absolute URLs as well,
           // which means we need to check that the extension is allowed
           // to load them. This will throw an error if it's not allowed.
-          this._checkURL(url, extension.principal);
+          this._checkURL(url, extension);
 
           result[size] = url;
         }
@@ -1303,8 +1303,8 @@ let IconDetails = {
           let lightURL = baseURI.resolve(light);
           let darkURL = baseURI.resolve(dark);
 
-          this._checkURL(lightURL, extension.principal);
-          this._checkURL(darkURL, extension.principal);
+          this._checkURL(lightURL, extension);
+          this._checkURL(darkURL, extension);
 
           let defaultURL = result[size];
           result[size] = {
@@ -1330,12 +1330,8 @@ let IconDetails = {
 
   // Checks if the extension is allowed to load the given URL with the specified principal.
   // This will throw an error if the URL is not allowed.
-  _checkURL(url, principal) {
-    try {
-      Services.scriptSecurityManager.checkLoadURIWithPrincipal(
-        principal, Services.io.newURI(url),
-        Services.scriptSecurityManager.DISALLOW_SCRIPT);
-    } catch (e) {
+  _checkURL(url, extension) {
+    if (!extension.checkLoadURL(url, {allowInheritsPrincipal: true})) {
       throw new ExtensionError(`Illegal URL ${url}`);
     }
   },

toolkit/components/extensions/ExtensionUtils.jsm

@@ -652,7 +652,32 @@ class MessageManagerProxy {
   }
 }
 
+function checkLoadURL(url, principal, options) {
+  let ssm = Services.scriptSecurityManager;
+
+  let flags = ssm.STANDARD;
+  if (!options.allowScript) {
+    flags |= ssm.DISALLOW_SCRIPT;
+  }
+  if (!options.allowInheritsPrincipal) {
+    flags |= ssm.DISALLOW_INHERIT_PRINCIPAL;
+  }
+  if (options.dontReportErrors) {
+    flags |= ssm.DONT_REPORT_ERRORS;
+  }
+
+  try {
+    ssm.checkLoadURIWithPrincipal(principal,
+                                  Services.io.newURI(url),
+                                  flags);
+  } catch (e) {
+    return false;
+  }
+  return true;
+}
+
 this.ExtensionUtils = {
+  checkLoadURL,
   defineLazyGetter,
   flushJarCache,
   getConsole,