1 files changed, 264 insertions, 0 deletions
diff --git a/browser/extensions/search-detection/extension/api.js b/browser/extensions/search-detection/extension/api.js
new file mode 100644
index 0000000000..873a2ecedd
--- /dev/null
+++ b/browser/extensions/search-detection/extension/api.js
@@ -0,0 +1,264 @@
+/* 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/. */
+
+"use strict";
+
+/* global ExtensionCommon, ExtensionAPI, Services, XPCOMUtils, ExtensionUtils */
+
+const { AddonManager } = ChromeUtils.importESModule(
+  "resource://gre/modules/AddonManager.sys.mjs"
+);
+const { WebRequest } = ChromeUtils.importESModule(
+  "resource://gre/modules/WebRequest.sys.mjs"
+);
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  AddonSearchEngine: "resource://gre/modules/AddonSearchEngine.sys.mjs",
+});
+
+// eslint-disable-next-line mozilla/reject-importGlobalProperties
+XPCOMUtils.defineLazyGlobalGetters(this, ["ChannelWrapper"]);
+
+XPCOMUtils.defineLazyGetter(this, "searchInitialized", () => {
+  if (Services.search.isInitialized) {
+    return Promise.resolve();
+  }
+
+  return ExtensionUtils.promiseObserved(
+    "browser-search-service",
+    (_, data) => data === "init-complete"
+  );
+});
+
+const SEARCH_TOPIC_ENGINE_MODIFIED = "browser-search-engine-modified";
+
+this.addonsSearchDetection = class extends ExtensionAPI {
+  getAPI(context) {
+    const { extension } = context;
+
+    // We want to temporarily store the first monitored URLs that have been
+    // redirected, indexed by request IDs, so that the background script can
+    // find the add-on IDs to report.
+    this.firstMatchedUrls = {};
+
+    return {
+      addonsSearchDetection: {
+        // `getMatchPatterns()` returns a map where each key is an URL pattern
+        // to monitor and its corresponding value is a list of add-on IDs
+        // (search engines).
+        //
+        // Note: We don't return a simple list of URL patterns because the
+        // background script might want to lookup add-on IDs for a given URL in
+        // the case of server-side redirects.
+        async getMatchPatterns() {
+          const patterns = {};
+
+          try {
+            await searchInitialized;
+            const visibleEngines = await Services.search.getEngines();
+
+            visibleEngines.forEach(engine => {
+              if (!(engine instanceof lazy.AddonSearchEngine)) {
+                return;
+              }
+              const { _extensionID, _urls } = engine.wrappedJSObject;
+
+              if (!_extensionID) {
+                // OpenSearch engines don't have an extension ID.
+                return;
+              }
+
+              _urls
+                // We only want to collect "search URLs" (and not "suggestion"
+                // ones for instance). See `URL_TYPE` in `SearchUtils.jsm`.
+                .filter(({ type }) => type === "text/html")
+                .forEach(({ template }) => {
+                  // If this is changed, double check the code in the background
+                  // script because `webRequestCancelledHandler` splits patterns
+                  // on `*` to retrieve URL prefixes.
+                  const pattern = template.split("?")[0] + "*";
+
+                  // Multiple search engines could register URL templates that
+                  // would become the same URL pattern as defined above so we
+                  // store a list of extension IDs per URL pattern.
+                  if (!patterns[pattern]) {
+                    patterns[pattern] = [];
+                  }
+
+                  // We exclude built-in search engines because we don't need
+                  // to report them.
+                  if (
+                    !patterns[pattern].includes(_extensionID) &&
+                    !_extensionID.endsWith("@search.mozilla.org")
+                  ) {
+                    patterns[pattern].push(_extensionID);
+                  }
+                });
+            });
+          } catch (err) {
+            console.error(err);
+          }
+
+          return patterns;
+        },
+
+        // `getAddonVersion()` returns the add-on version if it exists.
+        async getAddonVersion(addonId) {
+          const addon = await AddonManager.getAddonByID(addonId);
+
+          return addon && addon.version;
+        },
+
+        // `getPublicSuffix()` returns the public suffix/Effective TLD Service
+        // of the given URL.
+        // See: https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIEffectiveTLDService
+        async getPublicSuffix(url) {
+          try {
+            return Services.eTLD.getBaseDomain(Services.io.newURI(url));
+          } catch (err) {
+            console.error(err);
+            return null;
+          }
+        },
+
+        // `onSearchEngineModified` is an event that occurs when the list of
+        // search engines has changed, e.g., a new engine has been added or an
+        // engine has been removed.
+        //
+        // See: https://searchfox.org/mozilla-central/source/toolkit/components/search/SearchUtils.jsm#145-152
+        onSearchEngineModified: new ExtensionCommon.EventManager({
+          context,
+          name: "addonsSearchDetection.onSearchEngineModified",
+          register: fire => {
+            const onSearchEngineModifiedObserver = (
+              aSubject,
+              aTopic,
+              aData
+            ) => {
+              if (
+                aTopic !== SEARCH_TOPIC_ENGINE_MODIFIED ||
+                // We are only interested in these modified types.
+                !["engine-added", "engine-removed", "engine-changed"].includes(
+                  aData
+                )
+              ) {
+                return;
+              }
+
+              fire.async();
+            };
+
+            Services.obs.addObserver(
+              onSearchEngineModifiedObserver,
+              SEARCH_TOPIC_ENGINE_MODIFIED
+            );
+
+            return () => {
+              Services.obs.removeObserver(
+                onSearchEngineModifiedObserver,
+                SEARCH_TOPIC_ENGINE_MODIFIED
+              );
+            };
+          },
+        }).api(),
+
+        // `onRedirected` is an event fired after a request has stopped and
+        // this request has been redirected once or more. The registered
+        // listeners will received the following properties:
+        //
+        //   - `addonId`: the add-on ID that redirected the request, if any.
+        //   - `firstUrl`: the first monitored URL of the request that has
+        //      been redirected.
+        //   - `lastUrl`: the last URL loaded for the request, after one or
+        //      more redirects.
+        onRedirected: new ExtensionCommon.EventManager({
+          context,
+          name: "addonsSearchDetection.onRedirected",
+          register: (fire, filter) => {
+            const stopListener = event => {
+              if (event.type != "stop") {
+                return;
+              }
+
+              const wrapper = event.currentTarget;
+              const { channel, id: requestId } = wrapper;
+
+              // When we detected a redirect, we read the request property,
+              // hoping to find an add-on ID corresponding to the add-on that
+              // initiated the redirect. It might not return anything when the
+              // redirect is a search server-side redirect but it can also be
+              // caused by an error.
+              let addonId;
+              try {
+                addonId = channel
+                  ?.QueryInterface(Ci.nsIPropertyBag)
+                  ?.getProperty("redirectedByExtension");
+              } catch (err) {
+                console.error(err);
+              }
+
+              const firstUrl = this.firstMatchedUrls[requestId];
+              // We don't need this entry anymore.
+              delete this.firstMatchedUrls[requestId];
+
+              const lastUrl = wrapper.finalURL;
+
+              if (!firstUrl || !lastUrl) {
+                // Something went wrong but there is nothing we can do at this
+                // point.
+                return;
+              }
+
+              fire.sync({ addonId, firstUrl, lastUrl });
+            };
+
+            const listener = ({ requestId, url, originUrl }) => {
+              // We exclude requests not originating from the location bar,
+              // bookmarks and other "system-ish" requests.
+              if (originUrl !== undefined) {
+                return;
+              }
+
+              // Keep the first monitored URL that was redirected for the
+              // request until the request has stopped.
+              if (!this.firstMatchedUrls[requestId]) {
+                this.firstMatchedUrls[requestId] = url;
+
+                const wrapper = ChannelWrapper.getRegisteredChannel(
+                  requestId,
+                  context.extension.policy,
+                  context.xulBrowser.frameLoader.remoteTab
+                );
+
+                wrapper.addEventListener("stop", stopListener);
+              }
+            };
+
+            WebRequest.onBeforeRedirect.addListener(
+              listener,
+              // filter
+              {
+                types: ["main_frame"],
+                urls: ExtensionUtils.parseMatchPatterns(filter.urls),
+              },
+              // info
+              [],
+              // listener details
+              {
+                addonId: extension.id,
+                policy: extension.policy,
+                blockingAllowed: false,
+              }
+            );
+
+            return () => {
+              WebRequest.onBeforeRedirect.removeListener(listener);
+            };
+          },
+        }).api(),
+      },
+    };
+  }
+};