path: root/libre/iceweasel/9001-FSDG-sync-remote-settings-with-local-dump.patch

From e2e22a52ee5e5cf9f7c55854b828bb65a919b563 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:20:39 +0200
Subject: [PATCH 01/13] Point to local omni.ja files, not remote server

This patch series tries to remove any network communication with Remote
Settings [1], which can be used by Mozilla to silently push data to client
browsers. This data can include references to nonfree software, for example,
to search engines or other websites that contain nonfree JavaScript code.
Without this patching, it would be hard to make sure the browser does not
violate paragraph 4 of [2]: "Programs in the system should not suggest
installing nonfree plugins, documentation, and so on."

Changes in the current patch:
First of all, replace every occurrence of Remote Settings server domain name
with URIs that point to built-in local files within omni.ja.

Some links to json files may point to non-existing files, but that's OK
because it's better than leave them point to Remote Settings server.
If necessary, missing files can be added later.

[1] https://remote-settings.readthedocs.io/en/latest/introduction.html
[2] https://www.gnu.org/distros/free-system-distribution-guidelines.en.html#license-rules
---
 .../components/ASRouterAdmin/ASRouterAdmin.jsx            | 2 +-
 .../newtab/data/content/activity-stream.bundle.js         | 2 +-
 services/settings/Utils.jsm                               | 2 +-
 .../periodic-updates/scripts/periodic_file_updates.sh     | 2 +-
 toolkit/components/search/SearchUtils.jsm                 | 8 ++++----
 toolkit/components/search/docs/DefaultSearchEngines.rst   | 2 +-
 .../components/search/docs/SearchEngineConfiguration.rst  | 2 +-
 toolkit/modules/AppConstants.jsm                          | 4 ++--
 toolkit/mozapps/defaultagent/RemoteSettings.cpp           | 2 +-
 9 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/browser/components/newtab/content-src/components/ASRouterAdmin/ASRouterAdmin.jsx b/browser/components/newtab/content-src/components/ASRouterAdmin/ASRouterAdmin.jsx
index 0a9da8d804..fdc387aa63 100644
--- a/browser/components/newtab/content-src/components/ASRouterAdmin/ASRouterAdmin.jsx
+++ b/browser/components/newtab/content-src/components/ASRouterAdmin/ASRouterAdmin.jsx
@@ -1226,7 +1226,7 @@ export class ASRouterAdminInner extends React.PureComponent {
                   <a
                     className="providerUrl"
                     target="_blank"
-                    href="https://firefox.settings.services.mozilla.com/v1/buckets/main/collections/nimbus-desktop-experiments/records"
+                    href="resource://app/defaults/settings/main/nimbus-desktop-experiments.json"
                     rel="noopener noreferrer"
                   >
                     nimbus-desktop-experiments
diff --git a/browser/components/newtab/data/content/activity-stream.bundle.js b/browser/components/newtab/data/content/activity-stream.bundle.js
index 3439547610..e4b170454c 100644
--- a/browser/components/newtab/data/content/activity-stream.bundle.js
+++ b/browser/components/newtab/data/content/activity-stream.bundle.js
@@ -1577,7 +1577,7 @@ class ASRouterAdminInner extends (external_React_default()).PureComponent {
         label = /*#__PURE__*/external_React_default().createElement("span", null, "remote settings (", /*#__PURE__*/external_React_default().createElement("a", {
           className: "providerUrl",
           target: "_blank",
-          href: "https://firefox.settings.services.mozilla.com/v1/buckets/main/collections/nimbus-desktop-experiments/records",
+          href: "resource://app/defaults/settings/main/nimbus-desktop-experiments.json",
           rel: "noopener noreferrer"
         }, "nimbus-desktop-experiments"), ")");
       }
diff --git a/services/settings/Utils.jsm b/services/settings/Utils.jsm
index 31ad77d286..9f2e97f14c 100644
--- a/services/settings/Utils.jsm
+++ b/services/settings/Utils.jsm
@@ -106,7 +106,7 @@ var Utils = {
       : AppConstants.REMOTE_SETTINGS_SERVER_URL;
   },
 
-  CHANGES_PATH: "/buckets/monitor/collections/changes/changeset",
+  CHANGES_PATH: "/monitor/changes",
 
   /**
    * Logger instance.
diff --git a/taskcluster/docker/periodic-updates/scripts/periodic_file_updates.sh b/taskcluster/docker/periodic-updates/scripts/periodic_file_updates.sh
index 3bc70462c4..dc9592c9fa 100755
--- a/taskcluster/docker/periodic-updates/scripts/periodic_file_updates.sh
+++ b/taskcluster/docker/periodic-updates/scripts/periodic_file_updates.sh
@@ -285,7 +285,7 @@ function compare_suffix_lists {
 }
 
 function compare_remote_settings_files {
-  REMOTE_SETTINGS_SERVER="https://firefox.settings.services.mozilla.com/v1"
+  REMOTE_SETTINGS_SERVER="resource://app/defaults/settings"
 
   # 1. List remote settings collections from server.
   echo "INFO: fetch remote settings list from server"
diff --git a/toolkit/components/search/SearchUtils.jsm b/toolkit/components/search/SearchUtils.jsm
index 0bf60e5f16..5561b885f6 100644
--- a/toolkit/components/search/SearchUtils.jsm
+++ b/toolkit/components/search/SearchUtils.jsm
@@ -158,13 +158,13 @@ var SearchUtils = {
 
   ENGINES_URLS: {
     "prod-main":
-      "https://firefox.settings.services.mozilla.com/v1/buckets/main/collections/search-config/records",
+      "resource://app/defaults/settings/main/search-config.json",
     "prod-preview":
-      "https://firefox.settings.services.mozilla.com/v1/buckets/main-preview/collections/search-config/records",
+      "resource://app/defaults/settings/main/search-config.json",
     "stage-main":
-      "https://settings.stage.mozaws.net/v1/buckets/main/collections/search-config/records",
+      "resource://app/defaults/settings/main/search-config.json",
     "stage-preview":
-      "https://settings.stage.mozaws.net/v1/buckets/main-preview/collections/search-config/records",
+      "resource://app/defaults/settings/main/search-config.json",
   },
 
   // The following constants are left undocumented in nsISearchService.idl
diff --git a/toolkit/components/search/docs/DefaultSearchEngines.rst b/toolkit/components/search/docs/DefaultSearchEngines.rst
index 3dfe68abb1..26d5f18a7b 100644
--- a/toolkit/components/search/docs/DefaultSearchEngines.rst
+++ b/toolkit/components/search/docs/DefaultSearchEngines.rst
@@ -99,4 +99,4 @@ is updated.
 
 .. _configuration schema: SearchConfigurationSchema.html
 .. _remote settings: /services/settings/index.html
-.. _search-default-override-allowlist bucket: https://firefox.settings.services.mozilla.com/v1/buckets/main/collections/search-default-override-allowlist/records
+.. _search-default-override-allowlist bucket: resource://app/defaults/settings/main/search-default-override-allowlist.json
diff --git a/toolkit/components/search/docs/SearchEngineConfiguration.rst b/toolkit/components/search/docs/SearchEngineConfiguration.rst
index c782f9f7c3..4d773d27c5 100644
--- a/toolkit/components/search/docs/SearchEngineConfiguration.rst
+++ b/toolkit/components/search/docs/SearchEngineConfiguration.rst
@@ -68,5 +68,5 @@ related. As a result several situations may occur:
 .. _JSON schema: https://json-schema.org/
 .. _stored in mozilla-central: https://searchfox.org/mozilla-central/source/toolkit/components/search/schema/
 .. _Search Configuration Schema: SearchConfigurationSchema.html
-.. _viewed live: https://firefox.settings.services.mozilla.com/v1/buckets/main/collections/search-config/records
+.. _viewed live: resource://app/defaults/settings/main/search-config.json
 .. _Normandy: /toolkit/components/normandy/normandy/services.html
diff --git a/toolkit/modules/AppConstants.jsm b/toolkit/modules/AppConstants.jsm
index 7f8ac95dd9..fc34169ea5 100644
--- a/toolkit/modules/AppConstants.jsm
+++ b/toolkit/modules/AppConstants.jsm
@@ -420,9 +420,9 @@ this.AppConstants = Object.freeze({
 
   REMOTE_SETTINGS_SERVER_URL:
 #ifdef MOZ_THUNDERBIRD
-    "https://thunderbird-settings.thunderbird.net/v1",
+    "resource://app/defaults/settings",
 #else
-    "https://firefox.settings.services.mozilla.com/v1",
+    "resource://app/defaults/settings",
 #endif
 
   REMOTE_SETTINGS_VERIFY_SIGNATURE:
diff --git a/toolkit/mozapps/defaultagent/RemoteSettings.cpp b/toolkit/mozapps/defaultagent/RemoteSettings.cpp
index 667d9fc628..b2bf628f29 100644
--- a/toolkit/mozapps/defaultagent/RemoteSettings.cpp
+++ b/toolkit/mozapps/defaultagent/RemoteSettings.cpp
@@ -23,7 +23,7 @@ extern "C" {
 HRESULT IsAgentRemoteDisabledRust(const char* szUrl, DWORD* lpdwDisabled);
 }
 
-#define PROD_ENDPOINT "https://firefox.settings.services.mozilla.com/v1"
+#define PROD_ENDPOINT "resource://app/defaults/settings"
 #define PROD_BID "main"
 #define PROD_CID "windows-default-browser-agent"
 #define PROD_ID "state"
-- 
2.37.0


From 9329ba8b85b542759a089818d70ba86d0a5b9a60 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:34:08 +0200
Subject: [PATCH 02/13] Remove polling triggered by push broadcasts

When initialized, remote-settings.js adds a listener to push broadcasts,
that let Remote Settings server send push messages to trigger polling
for changes from the client side. This is not needed for local-only
setup. Remove the record from broadcast-listeners.json file stored in
the user profile, so that it doesn't get picked up by push broadcast
service.
---
 dom/push/PushBroadcastService.jsm    | 13 +++++++++++++
 services/settings/remote-settings.js |  7 ++-----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/dom/push/PushBroadcastService.jsm b/dom/push/PushBroadcastService.jsm
index 1ee7986f6a..db73413b1a 100644
--- a/dom/push/PushBroadcastService.jsm
+++ b/dom/push/PushBroadcastService.jsm
@@ -179,6 +179,19 @@ var BroadcastService = class {
     }
   }
 
+  async deleteListener(broadcastId) {
+    await this.initializePromise;
+
+    if (this.jsonFile.data.listeners.hasOwnProperty(broadcastId)) {
+      console.info(
+        "deleteListener: deleting listener",
+        broadcastId
+      );
+      delete this.jsonFile.data.listeners[broadcastId];
+      this.jsonFile.saveSoon();
+    }
+  }
+
   /**
    * Call the listeners of the specified broadcasts.
    *
diff --git a/services/settings/remote-settings.js b/services/settings/remote-settings.js
index f7e8e24748..57d11d71b3 100644
--- a/services/settings/remote-settings.js
+++ b/services/settings/remote-settings.js
@@ -533,7 +533,7 @@ function remoteSettingsFunction() {
       moduleURI: __URI__,
       symbolName: "remoteSettingsBroadcastHandler",
     };
-    pushBroadcastService.addListener(BROADCAST_ID, currentVersion, moduleInfo);
+    pushBroadcastService.deleteListener(BROADCAST_ID);
   };
 
   return remoteSettings;
@@ -553,9 +553,6 @@ var remoteSettingsBroadcastHandler = {
       `Push notification received (version=${version} phase=${phase})`
     );
 
-    return RemoteSettings.pollChanges({
-      expectedTimestamp: version,
-      trigger: isStartup ? "startup" : "broadcast",
-    });
+    return;
   },
 };
-- 
2.37.0


From 11631dd36d3eeecc5f22171d5e059fbe7662c77c Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:41:54 +0200
Subject: [PATCH 03/13] Remove timer that triggers polling for changes

That is not needed for local-only setup.
---
 services/settings/components.conf           | 9 +--------
 services/settings/servicesSettings.manifest | 4 ----
 2 files changed, 1 insertion(+), 12 deletions(-)

diff --git a/services/settings/components.conf b/services/settings/components.conf
index 9a737802ee..25109415a7 100644
--- a/services/settings/components.conf
+++ b/services/settings/components.conf
@@ -4,11 +4,4 @@
 # 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/.
 
-Classes = [
-    {
-        'cid': '{5e756573-234a-49ea-bbe4-59ec7a70657d}',
-        'contract_ids': ['@mozilla.org/services/settings;1'],
-        'jsm': 'resource://services-settings/RemoteSettingsComponents.jsm',
-        'constructor': 'RemoteSettingsTimer',
-    },
-]
+Classes = []
diff --git a/services/settings/servicesSettings.manifest b/services/settings/servicesSettings.manifest
index 3bfed26ea4..807eb220ec 100644
--- a/services/settings/servicesSettings.manifest
+++ b/services/settings/servicesSettings.manifest
@@ -1,7 +1,3 @@
 # Register resource aliases
 resource services-settings resource://gre/modules/services-settings/
 
-# Schedule polling of remote settings changes
-# (default 24H, max 72H)
-# see syntax https://searchfox.org/mozilla-central/rev/cc280c4be94ff8cf64a27cc9b3d6831ffa49fa45/toolkit/components/timermanager/UpdateTimerManager.jsm#155
-category update-timer RemoteSettingsComponents @mozilla.org/services/settings;1,getService,services-settings-poll-changes,services.settings.poll_interval,86400,259200
-- 
2.37.0


From d720d5680fa97ad53998b6050bc28df4503f0c39 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:47:41 +0200
Subject: [PATCH 04/13] Utils: fetch timestamps of each collection locally

Utils.CHANGES_PATH points to
services/settings/dumps/monitor/changes
which will be generated later by JSON processing script. Fetch the
timestamps from that file and mock response headers to not confuse any
code that expects them.
---
 browser/installer/package-manifest.in     |  1 +
 services/settings/Utils.jsm               | 18 +++++++++++++++---
 services/settings/dumps/monitor/moz.build |  8 ++++++++
 services/settings/dumps/moz.build         |  1 +
 4 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100644 services/settings/dumps/monitor/moz.build

diff --git a/browser/installer/package-manifest.in b/browser/installer/package-manifest.in
index 73a41dc25b..04c2a3fb6a 100644
--- a/browser/installer/package-manifest.in
+++ b/browser/installer/package-manifest.in
@@ -275,6 +275,7 @@
 @RESPATH@/browser/defaults/settings/last_modified.json
 @RESPATH@/browser/defaults/settings/blocklists
 @RESPATH@/browser/defaults/settings/main
+@RESPATH@/browser/defaults/settings/monitor
 @RESPATH@/browser/defaults/settings/security-state
 
 ; Warning: changing the path to channel-prefs.js can cause bugs (Bug 756325)
diff --git a/services/settings/Utils.jsm b/services/settings/Utils.jsm
index 9f2e97f14c..4e140f0fdd 100644
--- a/services/settings/Utils.jsm
+++ b/services/settings/Utils.jsm
@@ -377,7 +377,7 @@ var Utils = {
   async fetchLatestChanges(serverUrl, options = {}) {
     const { expectedTimestamp, lastEtag = "", filters = {} } = options;
 
-    let url = serverUrl + Utils.CHANGES_PATH;
+    let url = Utils.SERVER_URL + Utils.CHANGES_PATH;
     const params = {
       ...filters,
       _expected: expectedTimestamp ?? 0,
@@ -392,7 +392,11 @@ var Utils = {
           .map(([k, v]) => `${k}=${encodeURIComponent(v)}`)
           .join("&");
     }
-    const response = await Utils.fetch(url);
+    const response = await fetch(url);
+    const responseDate = new Date().toUTCString()
+    response.headers.set("Date", responseDate);
+    response.headers.set("Last-Modified", responseDate);
+    response.headers.set("Content-Type", "application/json");
 
     if (response.status >= 500) {
       throw new Error(`Server error ${response.status} ${response.statusText}`);
@@ -427,7 +431,15 @@ var Utils = {
       }
     }
 
-    const { changes = [], timestamp } = payload;
+    const { timestamp } = payload;
+    const { bucket, collection } = filters;
+    if (!bucket || !collection) {
+      throw new Error('Unable to fetch latest change without bucket or collection');
+    }
+    const change = payload.changes.find(
+        change => change.bucket === bucket && change.collection === collection
+      ) ?? { last_modified: 0, bucket, collection };
+    const changes = [change];
 
     let serverTimeMillis = Date.parse(response.headers.get("Date"));
     // Since the response is served via a CDN, the Date header value could have been cached.
diff --git a/services/settings/dumps/monitor/moz.build b/services/settings/dumps/monitor/moz.build
new file mode 100644
index 0000000000..25c53a2eeb
--- /dev/null
+++ b/services/settings/dumps/monitor/moz.build
@@ -0,0 +1,8 @@
+# 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/.
+
+FINAL_TARGET_FILES.defaults.settings.monitor += ["changes"]
+
+if CONFIG["MOZ_BUILD_APP"] == "browser":
+    DIST_SUBDIR = "browser"
diff --git a/services/settings/dumps/moz.build b/services/settings/dumps/moz.build
index f407580bfa..53e9d8b45e 100644
--- a/services/settings/dumps/moz.build
+++ b/services/settings/dumps/moz.build
@@ -5,6 +5,7 @@
 DIRS += [
     "blocklists",
     "main",
+    "monitor",
     "security-state",
 ]
 
-- 
2.37.0


From 98496943d01589201771f69e14ba6b3cb7395e48 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:52:10 +0200
Subject: [PATCH 05/13] Utils: disable offline checking

Since only local data is read now, it should always return false for the
current and any future code that relies on it.
---
 services/settings/Utils.jsm | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/services/settings/Utils.jsm b/services/settings/Utils.jsm
index 4e140f0fdd..5d448da54c 100644
--- a/services/settings/Utils.jsm
+++ b/services/settings/Utils.jsm
@@ -192,15 +192,6 @@ var Utils = {
    * @return {bool} Whether network is down or not.
    */
   get isOffline() {
-    try {
-      return (
-        Services.io.offline ||
-        CaptivePortalService.state == CaptivePortalService.LOCKED_PORTAL ||
-        !gNetworkLinkService.isLinkUp
-      );
-    } catch (ex) {
-      log.warn("Could not determine network status.", ex);
-    }
     return false;
   },
 
-- 
2.37.0


From 738c1836a53ead5253ab3e0f9750aec94192dff0 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 17:56:02 +0200
Subject: [PATCH 06/13] Refactor hashing logic to a separate function

It is used instead of internal signature validation mechanism, for
integrity checking of the locally cached data.
---
 services/settings/RemoteSettingsWorker.jsm | 4 ++++
 services/settings/SharedUtils.jsm          | 9 +++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/services/settings/RemoteSettingsWorker.jsm b/services/settings/RemoteSettingsWorker.jsm
index 147ebb6b13..c86e218fd3 100644
--- a/services/settings/RemoteSettingsWorker.jsm
+++ b/services/settings/RemoteSettingsWorker.jsm
@@ -189,6 +189,10 @@ class Worker {
     // task on the current thread instead of the worker thread.
     return SharedUtils.checkContentHash(buffer, size, hash);
   }
+
+  async getContentHash(bytes) {
+    return SharedUtils.getContentHash(bytes);
+  }
 }
 
 // Now, first add a shutdown blocker. If that fails, we must have
diff --git a/services/settings/SharedUtils.jsm b/services/settings/SharedUtils.jsm
index 5d32fb38bd..753a1b1393 100644
--- a/services/settings/SharedUtils.jsm
+++ b/services/settings/SharedUtils.jsm
@@ -28,11 +28,16 @@ var SharedUtils = {
       return false;
     }
     // Has expected content?
+    const hashStr = await this.getContentHash(bytes);
+    return hashStr == hash;
+  },
+
+  async getContentHash(bytes) {
     const hashBuffer = await crypto.subtle.digest("SHA-256", bytes);
     const hashBytes = new Uint8Array(hashBuffer);
     const toHex = b => b.toString(16).padStart(2, "0");
-    const hashStr = Array.from(hashBytes, toHex).join("");
-    return hashStr == hash;
+
+    return Array.from(hashBytes, toHex).join("");
   },
 
   /**
-- 
2.37.0


From fa07a0a3fbd62a0d973a4ca07fdc3a5cf2209841 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 18:05:02 +0200
Subject: [PATCH 07/13] Client: Fetch and hash records from local dump

Read the records from local dumps. See [1] for details on how to prepare
custom dumps). Records are cached in the local IndexedDB, and the client
updates cached records each time there's a change. Also it verifies
integrity of the data. Then the list of current / created / updated /
deleted records is generated and emitted to every registered listener.

Change upstream signature validation mechanism to a simpler one.
Otherwise, it'd be necessary to sign local records, which is redundant,
because the application package should be signed already by the distro.

Instead of signature property from metadata records, json_dump_metadata
has been introduced. It contains the checksum of the records and size in
bytes. Also added app_build_id property for version checking and updates
of cached data.

Although it's possible to disable integrity checking via preference, it
seems to be not a good idea, because the logic that detects invalid
local data relies on it. In the context of local-only setup, data that
has been received from real Remote Settings server will not contain the
custom metadata, and thus will be considered invalid and then discarded,
while the client gets a chance to gracefully inform registered listeners
about these changes so that they can discard the data received before
the upgrade to local-only setup.

[1] https://firefox-source-docs.mozilla.org/services/common/services/RemoteSettings.html#initial-data
---
 services/settings/RemoteSettingsClient.jsm | 63 ++++++++++------------
 1 file changed, 27 insertions(+), 36 deletions(-)

diff --git a/services/settings/RemoteSettingsClient.jsm b/services/settings/RemoteSettingsClient.jsm
index eee1487491..90e82772c4 100644
--- a/services/settings/RemoteSettingsClient.jsm
+++ b/services/settings/RemoteSettingsClient.jsm
@@ -592,11 +592,9 @@ class RemoteSettingsClient extends EventEmitter {
 
           // If the data is up-to-date but don't have metadata (records loaded from dump),
           // we fetch them and validate the signature immediately.
-          if (this.verifySignature && ObjectUtils.isEmpty(localMetadata)) {
+          if (this.verifySignature && ObjectUtils.isEmpty(localMetadata?.json_dump_metadata)) {
             console.debug(`${this.identifier} pull collection metadata`);
-            const metadata = await this.httpClient().getData({
-              query: { _expected: expectedTimestamp },
-            });
+            const { metadata } = await this._fetchChangeset(expectedTimestamp);
             await this.db.importChanges(metadata);
             // We don't bother validating the signature if the dump was just loaded. We do
             // if the dump was loaded at some other point (eg. from .get()).
@@ -825,33 +823,23 @@ class RemoteSettingsClient extends EventEmitter {
    * @returns {Promise}
    */
   async _validateCollectionSignature(records, timestamp, metadata) {
-    if (!metadata?.signature) {
+    if (!metadata?.json_dump_metadata) {
       throw new MissingSignatureError(this.identifier);
     }
 
-    if (!this._verifier) {
-      this._verifier = Cc[
-        "@mozilla.org/security/contentsignatureverifier;1"
-      ].createInstance(Ci.nsIContentSignatureVerifier);
-    }
-
-    // This is a content-signature field from an autograph response.
     const {
-      signature: { x5u, signature },
+      json_dump_metadata: { hash, size },
     } = metadata;
-    const certChain = await (await Utils.fetch(x5u)).text();
     // Merge remote records with local ones and serialize as canonical JSON.
     const serialized = await RemoteSettingsWorker.canonicalStringify(
       records,
       timestamp
     );
     if (
-      !(await this._verifier.asyncVerifyContentSignature(
-        serialized,
-        "p384ecdsa=" + signature,
-        certChain,
-        this.signerName,
-        Utils.CERT_CHAIN_ROOT_IDENTIFIER
+      !(await RemoteSettingsWorker.checkContentHash(
+        new TextEncoder().encode(serialized),
+        size,
+        hash
       ))
     ) {
       throw new InvalidSignatureError(this.identifier);
@@ -1024,24 +1012,27 @@ class RemoteSettingsClient extends EventEmitter {
    * @param since timestamp of last sync (optional)
    */
   async _fetchChangeset(expectedTimestamp, since) {
-    const client = this.httpClient();
-    const {
-      metadata,
-      timestamp: remoteTimestamp,
-      changes: remoteRecords,
-    } = await client.execute(
-      {
-        path: `/buckets/${this.bucketName}/collections/${this.collectionName}/changeset`,
-      },
-      {
-        query: {
-          _expected: expectedTimestamp,
-          _since: since,
-        },
-      }
+    const { data } = await SharedUtils.loadJSONDump(
+      this.bucketName,
+      this.collectionName
     );
+    const remoteRecords = data ?? [];
+
+    const serialized = await RemoteSettingsWorker.canonicalStringify(
+      remoteRecords,
+      expectedTimestamp
+    );
+    const bytes = new TextEncoder().encode(serialized);
+    const metadata = {
+      app_build_id: Services.appinfo.appBuildID,
+      json_dump_metadata: {
+        hash: await RemoteSettingsWorker.getContentHash(bytes),
+        size: bytes.length,
+      },
+    }
+
     return {
-      remoteTimestamp,
+      remoteTimestamp: expectedTimestamp,
       metadata,
       remoteRecords,
     };
-- 
2.37.0


From 9e4840347d561c7dc98ab6f84e3c3a195297c29e Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 18:42:56 +0200
Subject: [PATCH 08/13] Client: start deferred sync on get() or on()

The users of the RemoteSettingsClient.jsm can receive records from it in
two ways: by calling get(), and by subscribing to events by calling
on().

So hook a deferred sync whenever something calls these methods. Because
multiple of those calls can be made quite early and in very short time,
set up a deferred task that will be armed only when needed and only once
in a second. When the task is running it first checks if the local data
came from the dump of the current app build, and no-ops if true. If
false, it triggers a sync. Then adds a flag if the client has been
correctly synchronized with the dump, so that no metadata checking
occurs during the session.
---
 services/settings/RemoteSettingsClient.jsm | 30 +++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/services/settings/RemoteSettingsClient.jsm b/services/settings/RemoteSettingsClient.jsm
index 90e82772c4..2a009eca7c 100644
--- a/services/settings/RemoteSettingsClient.jsm
+++ b/services/settings/RemoteSettingsClient.jsm
@@ -16,6 +16,7 @@ XPCOMUtils.defineLazyModuleGetters(this, {
   ClientEnvironmentBase:
     "resource://gre/modules/components-utils/ClientEnvironment.jsm",
   Database: "resource://services-settings/Database.jsm",
+  DeferredTask: "resource://gre/modules/DeferredTask.jsm",
   Downloader: "resource://services-settings/Attachments.jsm",
   IDBHelpers: "resource://services-settings/IDBHelpers.jsm",
   KintoHttpClient: "resource://services-common/kinto-http-client.js",
@@ -27,6 +28,7 @@ XPCOMUtils.defineLazyModuleGetters(this, {
 });
 
 const TELEMETRY_COMPONENT = "remotesettings";
+const DEFERRED_SYNC_DELAY_MILLISECONDS = 1000;
 
 XPCOMUtils.defineLazyGetter(this, "console", () => Utils.log);
 
@@ -249,6 +251,14 @@ class RemoteSettingsClient extends EventEmitter {
     this._lastCheckTimePref = lastCheckTimePref;
     this._verifier = null;
     this._syncRunning = false;
+    this._deferredSync = new DeferredTask(
+      async () => {
+        if (!this._syncRunning && !(await this._isSynced())) {
+          await this.sync();
+        }
+      },
+      DEFERRED_SYNC_DELAY_MILLISECONDS
+    );
 
     // This attribute allows signature verification to be disabled, when running tests
     // or when pulling data from a dev server.
@@ -278,6 +288,11 @@ class RemoteSettingsClient extends EventEmitter {
     this.db.identifier = this.identifier;
   }
 
+  on(event, callback) {
+    super.on(event, callback);
+    this._deferredSync.arm();
+  }
+
   get identifier() {
     return `${this.bucketName}/${this.collectionName}`;
   }
@@ -346,6 +361,10 @@ class RemoteSettingsClient extends EventEmitter {
       let lastModified = await this.db.getLastModified();
       let hasLocalData = lastModified !== null;
 
+      if (!(await this._isSynced())) {
+        throw new MissingSignatureError(this.identifier);
+      }
+
       if (syncIfEmpty && !hasLocalData) {
         // .get() was called before we had the chance to synchronize the local database.
         // We'll try to avoid returning an empty list.
@@ -444,7 +463,10 @@ class RemoteSettingsClient extends EventEmitter {
       // No need to verify signature on JSON dumps.
       // If local DB cannot be read, then we don't even try to do anything,
       // we return results early.
-      return this._filterEntries(data);
+      const filtered = this._filterEntries(data);
+      this._deferredSync.arm();
+
+      return filtered;
     }
 
     console.debug(
@@ -484,6 +506,12 @@ class RemoteSettingsClient extends EventEmitter {
     return final;
   }
 
+  async _isSynced() {
+    this._synced ||=
+      Services.appinfo.appBuildID === (await this.db.getMetadata())?.app_build_id;
+    return this._synced;
+  }
+
   /**
    * Synchronize the local database with the remote server.
    *
-- 
2.37.0


From 72de3dbe162430638a58838b714f1872c2dd8195 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 18:53:51 +0200
Subject: [PATCH 09/13] Client: deep compare records if timestamps match

When the list of current / updated / deleted records is generated, their
modification timestamps are compared to detect the updates.

Although in practice this is unlikely to happen, in theory the
timestamp of some older record received from Remote Settings can match
with the modified record in the dump. Although JSON processing script
makes sure to add unique timestamps to each of the modified records,
it's still possible to update dumps manually and simply forget to update
timestamps. So serialize the records and compare them as strings to be
on the safe side. This should happen only once after upgrading to each
new version of the application, so is not likely to introduce any
noticeable performance issues.
---
 services/settings/RemoteSettingsClient.jsm | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/services/settings/RemoteSettingsClient.jsm b/services/settings/RemoteSettingsClient.jsm
index 2a009eca7c..dbcdb559df 100644
--- a/services/settings/RemoteSettingsClient.jsm
+++ b/services/settings/RemoteSettingsClient.jsm
@@ -13,6 +13,7 @@ const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
 
 XPCOMUtils.defineLazyModuleGetters(this, {
   AppConstants: "resource://gre/modules/AppConstants.jsm",
+  CanonicalJSON: "resource://gre/modules/CanonicalJSON.jsm",
   ClientEnvironmentBase:
     "resource://gre/modules/components-utils/ClientEnvironment.jsm",
   Database: "resource://services-settings/Database.jsm",
@@ -1015,7 +1016,10 @@ class RemoteSettingsClient extends EventEmitter {
         const old = oldById.get(r.id);
         if (old) {
           oldById.delete(r.id);
-          if (r.last_modified != old.last_modified) {
+          if (
+            r.last_modified != old.last_modified ||
+            CanonicalJSON.stringify(r) != CanonicalJSON.stringify(old)
+          ) {
             syncResult.updated.push({ old, new: r });
           }
         } else {
-- 
2.37.0


From 0ddc970c40569ca7b20ec67a413519589e7c52f6 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 19:01:39 +0200
Subject: [PATCH 10/13] Client: delete more data on cleanup

When the client detects the local data is invalid (i.e. it came from
real Remote Settings and can have unwanted records), delete not only
the records, but also the attachments that came with them, because they
too can be problematic. And last check time preference, because it's not
useful anyway when remote-settings.js doesn't do any polling for changes.

Note that attachments should be deleted before the records, because the
logic gets the data about the attachments from those records.
---
 services/settings/RemoteSettingsClient.jsm | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/services/settings/RemoteSettingsClient.jsm b/services/settings/RemoteSettingsClient.jsm
index dbcdb559df..c20ce412b2 100644
--- a/services/settings/RemoteSettingsClient.jsm
+++ b/services/settings/RemoteSettingsClient.jsm
@@ -207,7 +207,7 @@ class AttachmentDownloader extends Downloader {
       allRecords
         .filter(r => !!r.attachment)
         .map(r =>
-          Promise.all([this.deleteDownloaded(r), this.deleteFromDisk(r)])
+          Promise.all([this.deleteDownloaded(r), this.deleteFromDisk(r), this.deleteCached(r.id)])
         )
     );
   }
@@ -975,7 +975,7 @@ class RemoteSettingsClient extends EventEmitter {
           // Signature failed, clear local DB because it contains
           // bad data (local + remote changes).
           console.debug(`${this.identifier} clear local data`);
-          await this.db.clear();
+          await this._clearAll();
           // Local data was tampered, throw and it will retry from empty DB.
           console.error(`${this.identifier} local data was corrupted`);
           throw new CorruptedDataError(this.identifier);
@@ -997,7 +997,7 @@ class RemoteSettingsClient extends EventEmitter {
             // _importJSONDump() only clears DB if dump is available,
             // therefore do it here!
             if (imported < 0) {
-              await this.db.clear();
+              await this._clearAll();
             }
           }
         }
@@ -1037,6 +1037,12 @@ class RemoteSettingsClient extends EventEmitter {
     return syncResult;
   }
 
+  async _clearAll() {
+    await this.attachments.deleteAll();
+    await this.db.clear();
+    Services.prefs.clearUserPref(this.lastCheckTimePref);
+  }
+
   /**
    * Fetch information from changeset endpoint.
    *
-- 
2.37.0


From 00e45ee5b33b5e6030fa2d3b589cce5418822a3e Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 19:07:56 +0200
Subject: [PATCH 11/13] Client: remove comparison of collection timestamps

In case if the cached data that came from real Remote Settings server
(before the upgrade to local-only setup) has collection timestamp, that
is newer than the packaged local dump, then this comparison logic can
lead to early return of old data, skipping the integrity checking and
necessary cleanup. So remove the checks.
---
 services/settings/RemoteSettingsClient.jsm | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/services/settings/RemoteSettingsClient.jsm b/services/settings/RemoteSettingsClient.jsm
index c20ce412b2..79ec40ee9e 100644
--- a/services/settings/RemoteSettingsClient.jsm
+++ b/services/settings/RemoteSettingsClient.jsm
@@ -917,14 +917,9 @@ class RemoteSettingsClient extends EventEmitter {
       updated: [],
       deleted: [],
     };
-    // If data wasn't changed, return empty sync result.
-    // This can happen when we update the signature but not the data.
     console.debug(
       `${this.identifier} local timestamp: ${localTimestamp}, remote: ${remoteTimestamp}`
     );
-    if (localTimestamp && remoteTimestamp < localTimestamp) {
-      return syncResult;
-    }
 
     await this.db.importChanges(metadata, remoteTimestamp, remoteRecords, {
       clear: retry,
-- 
2.37.0


From 37d74c55d8c1d852666f179fe6ea45fd99ff83ca Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 19:15:44 +0200
Subject: [PATCH 12/13] Attachments: load only from dump and drop cached

---
 services/settings/Attachments.jsm | 35 +++++++------------------------
 1 file changed, 8 insertions(+), 27 deletions(-)

diff --git a/services/settings/Attachments.jsm b/services/settings/Attachments.jsm
index 2bf846e4e1..542f34f97e 100644
--- a/services/settings/Attachments.jsm
+++ b/services/settings/Attachments.jsm
@@ -151,9 +151,10 @@ class Downloader {
       retries,
       checkHash,
       attachmentId = record?.id,
-      fallbackToCache = false,
       fallbackToDump = false,
     } = options || {};
+    const fallbackToCache = false;
+    
     if (!attachmentId) {
       // Check for pre-condition. This should not happen, but it is explicitly
       // checked to avoid mixing up attachments, which could be dangerous.
@@ -204,6 +205,7 @@ class Downloader {
         const newBuffer = await this.downloadAsBytes(record, {
           retries,
           checkHash,
+          dumpInfo,
         });
         const blob = new Blob([newBuffer]);
         // Store in cache but don't wait for it before returning.
@@ -237,7 +239,7 @@ class Downloader {
       }
 
       try {
-        return { ...(await cacheInfo.getResult()), _source: "cache_fallback" };
+        await this.cacheImpl.delete(attachmentId);
       } catch (e) {
         // Failed to read from cache, e.g. IndexedDB unusable.
         Cu.reportError(e);
@@ -300,7 +302,7 @@ class Downloader {
    * @returns {String} the absolute file path to the downloaded attachment.
    */
   async downloadToDisk(record, options = {}) {
-    const { retries = 3 } = options;
+    const retries = 0;
     const {
       attachment: { filename, size, hash },
     } = record;
@@ -357,31 +359,10 @@ class Downloader {
    */
   async downloadAsBytes(record, options = {}) {
     const {
-      attachment: { location, hash, size },
-    } = record;
-
-    const remoteFileUrl = (await this._baseAttachmentsURL()) + location;
+      dumpInfo = new LazyRecordAndBuffer(() => this._readAttachmentDump(attachmentId))
+    } = options;
 
-    const { retries = 3, checkHash = true } = options;
-    let retried = 0;
-    while (true) {
-      try {
-        const buffer = await this._fetchAttachment(remoteFileUrl);
-        if (!checkHash) {
-          return buffer;
-        }
-        if (await RemoteSettingsWorker.checkContentHash(buffer, size, hash)) {
-          return buffer;
-        }
-        // Content is corrupted.
-        throw new Downloader.BadContentError(location);
-      } catch (e) {
-        if (retried >= retries) {
-          throw e;
-        }
-      }
-      retried++;
-    }
+    return (await dumpInfo.getResult()).buffer;
   }
 
   /**
-- 
2.37.0


From 5f475d79389de681e2eac63527a6d497b0b0da77 Mon Sep 17 00:00:00 2001
From: grizzlyuser <grizzlyuser@protonmail.com>
Date: Wed, 30 Dec 2020 19:22:20 +0200
Subject: [PATCH 13/13] Disable CRLite entirely for now

It's designed to fetch the data from Remote Settings. One of the main
selling points is that new revocations can be pushed to the clients
within minutes. That won't work with local-only setup. Although (some?)
of the JSON dumps for it are in place, obviously the updates won't
happen that fast.

Disable the preference right in the source code, so that the patch fails
to apply when the upstream decides to set it to fully enforcing mode
by default.

The solution with CRLite is up for discussion. If necessary, it's
possible to make clients for blessed collections to communicate to real
Remote Settings server. For example, for collections related to
certificate revocations.
---
 modules/libpref/init/StaticPrefList.yaml | 2 +-
 security/manager/ssl/nsNSSComponent.cpp  | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index c487b04a35..b0808338ef 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -12269,7 +12269,7 @@
 # 3: Consult CRLite and enforce "Not Revoked" results, but defer to OCSP for "Revoked".
 - name: security.pki.crlite_mode
   type: RelaxedAtomicUint32
-  value: 3
+  value: 0
   mirror: always
 
 - name: security.tls.version.min
diff --git a/security/manager/ssl/nsNSSComponent.cpp b/security/manager/ssl/nsNSSComponent.cpp
index 12da07c56f..39f85cf5b3 100644
--- a/security/manager/ssl/nsNSSComponent.cpp
+++ b/security/manager/ssl/nsNSSComponent.cpp
@@ -1453,6 +1453,7 @@ void nsNSSComponent::setValidationOptions(
   CRLiteMode defaultCRLiteMode = CRLiteMode::Disabled;
   CRLiteMode crliteMode =
       static_cast<CRLiteMode>(StaticPrefs::security_pki_crlite_mode());
+  // Adding a comment just in case so that the patch breaks as soon as any surrounding lines get changed
   switch (crliteMode) {
     case CRLiteMode::Disabled:
     case CRLiteMode::TelemetryOnly:
-- 
2.37.0