1 files changed, 104 insertions, 0 deletions
diff --git a/netwerk/dns/PublicSuffixList.sys.mjs b/netwerk/dns/PublicSuffixList.sys.mjs
new file mode 100644
index 0000000000..89cec38fea
--- /dev/null
+++ b/netwerk/dns/PublicSuffixList.sys.mjs
@@ -0,0 +1,104 @@
+/* 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/. */
+
+import { RemoteSettings } from "resource://services-settings/remote-settings.sys.mjs";
+
+const FileUtils = ChromeUtils.importESModule(
+  "resource://gre/modules/FileUtils.sys.mjs"
+).FileUtils;
+
+const RECORD_ID = "tld-dafsa";
+const SIGNAL = "public-suffix-list-updated";
+
+export const PublicSuffixList = {
+  CLIENT: RemoteSettings("public-suffix-list"),
+
+  init() {
+    // Only initialize once.
+    if (this._initialized) {
+      return;
+    }
+    this._initialized = true;
+
+    this.CLIENT.on("sync", this.onUpdate.bind(this));
+    /* We have a single record for this collection. Let's see if we already have it locally.
+     * Note that on startup, we don't need to synchronize immediately on new profiles.
+     */
+    this.CLIENT.get({ syncIfEmpty: false, filters: { id: RECORD_ID } })
+      .then(async records => {
+        if (records.length == 1) {
+          // Get the downloaded file URI (most likely to be a no-op here, since file will exist).
+          const fileURI = await this.CLIENT.attachments.downloadToDisk(
+            records[0]
+          );
+          // Send a signal so that the C++ code loads the updated list on startup.
+          this.notifyUpdate(fileURI);
+        }
+      })
+      .catch(err => console.error(err));
+  },
+
+  /**
+   * This method returns the path to the file based on the file uri received
+   * Example:
+   * On windows "file://C:/Users/AppData/main/public-suffix-list/dafsa.bin"
+   * will be converted to "C:\\Users\\main\\public-suffix-list\\dafsa.bin
+   *
+   * On macOS/linux "file:///home/main/public-suffix-list/dafsa.bin"
+   * will be converted to "/home/main/public-suffix-list/dafsa.bin"
+   */
+  getFilePath(fileURI) {
+    const uri = Services.io.newURI(fileURI);
+    const file = uri.QueryInterface(Ci.nsIFileURL).file;
+    return file.path;
+  },
+
+  notifyUpdate(fileURI) {
+    if (!Services.prefs.getBoolPref("network.psl.onUpdate_notify", false)) {
+      // Updating the PSL while Firefox is running could cause principals to
+      // have a different base domain before/after the update.
+      // See bug 1582647 comment 30
+      return;
+    }
+
+    const filePath = this.getFilePath(fileURI);
+    const nsifile = new FileUtils.File(filePath);
+    /* Send a signal to be read by the C++, the method
+     * ::Observe(nsISupports* aSubject, const char* aTopic, const char16_t* aData)
+     * at netwerk/dns/nsEffectiveTLDService.cpp
+     */
+    Services.obs.notifyObservers(
+      nsifile, // aSubject
+      SIGNAL, // aTopic
+      filePath // aData
+    );
+  },
+
+  async onUpdate({ data: { created, updated, deleted } }) {
+    // In theory, this will never happen, we will never delete the record.
+    if (deleted.length == 1) {
+      await this.CLIENT.attachments.deleteFromDisk(deleted[0]);
+    }
+    // Handle creation and update the same way
+    const changed = created.concat(updated.map(u => u.new));
+    /* In theory, we should never have more than one record. And if we receive
+     * this event, it's because the single record was updated.
+     */
+    if (changed.length != 1) {
+      console.warn("Unsupported sync event for Public Suffix List");
+      return;
+    }
+    // Download the updated file.
+    let fileURI;
+    try {
+      fileURI = await this.CLIENT.attachments.downloadToDisk(changed[0]);
+    } catch (err) {
+      console.error(err);
+      return;
+    }
+
+    // Notify the C++ part to reload it from disk.
+    this.notifyUpdate(fileURI);
+  },
+};