From 60d348e7cb4a405d467504cfa7d89c8e19352f96 Mon Sep 17 00:00:00 2001
From: Evan Hahn <69474926+EvanHahn-Signal@users.noreply.github.com>
Date: Wed, 2 Feb 2022 12:29:01 -0600
Subject: [PATCH] Open all Signal links in app

---
 app/main.ts                        |  7 +++-
 ts/test-node/util/sgnlHref_test.ts | 61 +++++++++++++++++++++++++++++-
 ts/util/sgnlHref.ts                | 29 ++++++++++++--
 3 files changed, 90 insertions(+), 7 deletions(-)

diff --git a/app/main.ts b/app/main.ts
index ca31ef5df..7af5c9ffa 100644
--- a/app/main.ts
+++ b/app/main.ts
@@ -82,6 +82,7 @@ import {
   parseSgnlHref,
   parseCaptchaHref,
   parseSignalHttpsLink,
+  rewriteSignalHrefsIfNecessary,
 } from '../ts/util/sgnlHref';
 import { toggleMaximizedBrowserWindow } from '../ts/util/toggleMaximizedBrowserWindow';
 import {
@@ -334,13 +335,15 @@ function prepareUrl(
   }).href;
 }
 
-async function handleUrl(event: Electron.Event, target: string) {
+async function handleUrl(event: Electron.Event, rawTarget: string) {
   event.preventDefault();
-  const parsedUrl = maybeParseUrl(target);
+  const parsedUrl = maybeParseUrl(rawTarget);
   if (!parsedUrl) {
     return;
   }
 
+  const target = rewriteSignalHrefsIfNecessary(rawTarget);
+
   const { protocol, hostname } = parsedUrl;
   const isDevServer =
     process.env.SIGNAL_ENABLE_HTTP && hostname === 'localhost';
diff --git a/ts/test-node/util/sgnlHref_test.ts b/ts/test-node/util/sgnlHref_test.ts
index 66e8e298c..5ba29c4fe 100644
--- a/ts/test-node/util/sgnlHref_test.ts
+++ b/ts/test-node/util/sgnlHref_test.ts
@@ -1,4 +1,4 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import { assert } from 'chai';
@@ -13,6 +13,7 @@ import {
   parseCaptchaHref,
   parseE164FromSignalDotMeHash,
   parseSignalHttpsLink,
+  rewriteSignalHrefsIfNecessary,
 } from '../../util/sgnlHref';
 
 function shouldNeverBeCalled() {
@@ -380,4 +381,62 @@ describe('sgnlHref', () => {
       );
     });
   });
+
+  describe('rewriteSignalHrefsIfNecessary', () => {
+    it('rewrites http://signal.group hrefs, making them use HTTPS', () => {
+      assert.strictEqual(
+        rewriteSignalHrefsIfNecessary('http://signal.group/#abc123'),
+        'https://signal.group/#abc123'
+      );
+    });
+
+    it('rewrites http://signal.art hrefs, making them use HTTPS', () => {
+      assert.strictEqual(
+        rewriteSignalHrefsIfNecessary(
+          'http://signal.art/addstickers/#pack_id=abc123'
+        ),
+        'https://signal.art/addstickers/#pack_id=abc123'
+      );
+    });
+
+    it('rewrites http://signal.me hrefs, making them use HTTPS', () => {
+      assert.strictEqual(
+        rewriteSignalHrefsIfNecessary('http://signal.me/#p/+18885551234'),
+        'https://signal.me/#p/+18885551234'
+      );
+    });
+
+    it('removes auth if present', () => {
+      assert.strictEqual(
+        rewriteSignalHrefsIfNecessary(
+          'http://user:pass@signal.group/ab?c=d#ef'
+        ),
+        'https://signal.group/ab?c=d#ef'
+      );
+      assert.strictEqual(
+        rewriteSignalHrefsIfNecessary(
+          'https://user:pass@signal.group/ab?c=d#ef'
+        ),
+        'https://signal.group/ab?c=d#ef'
+      );
+    });
+
+    it('does nothing to other hrefs', () => {
+      [
+        // Normal URLs
+        'http://example.com',
+        // Already HTTPS
+        'https://signal.art/addstickers/#pack_id=abc123',
+        // Different port
+        'http://signal.group:1234/abc?d=e#fg',
+        // Different subdomain
+        'http://subdomain.signal.group/#abcdef',
+        // Different protocol
+        'ftp://signal.group/#abc123',
+        'ftp://user:pass@signal.group/#abc123',
+      ].forEach(href => {
+        assert.strictEqual(rewriteSignalHrefsIfNecessary(href), href);
+      });
+    });
+  });
 });
diff --git a/ts/util/sgnlHref.ts b/ts/util/sgnlHref.ts
index 043baaa13..3bcf95ce9 100644
--- a/ts/util/sgnlHref.ts
+++ b/ts/util/sgnlHref.ts
@@ -1,10 +1,11 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import type { LoggerType } from '../types/Logging';
 import { maybeParseUrl } from './url';
 import { isValidE164 } from './isValidE164';
 
+const SIGNAL_HOSTS = new Set(['signal.group', 'signal.art', 'signal.me']);
 const SIGNAL_DOT_ME_HASH_PREFIX = 'p/';
 
 function parseUrl(value: string | URL, logger: LoggerType): undefined | URL {
@@ -44,9 +45,7 @@ export function isSignalHttpsLink(
       !url.password &&
       !url.port &&
       url.protocol === 'https:' &&
-      (url.host === 'signal.group' ||
-        url.host === 'signal.art' ||
-        url.host === 'signal.me')
+      SIGNAL_HOSTS.has(url.host)
   );
 }
 
@@ -143,3 +142,25 @@ export function parseE164FromSignalDotMeHash(hash: string): undefined | string {
   const maybeE164 = hash.slice(SIGNAL_DOT_ME_HASH_PREFIX.length);
   return isValidE164(maybeE164, true) ? maybeE164 : undefined;
 }
+
+/**
+ * Converts `http://signal.group/#abc` to `https://signal.group/#abc`. Does the same for
+ * other Signal hosts, like signal.me. Does nothing to other URLs. Expects a valid href.
+ */
+export function rewriteSignalHrefsIfNecessary(href: string): string {
+  const resultUrl = new URL(href);
+
+  const isHttp = resultUrl.protocol === 'http:';
+  const isHttpOrHttps = isHttp || resultUrl.protocol === 'https:';
+
+  if (SIGNAL_HOSTS.has(resultUrl.host) && isHttpOrHttps) {
+    if (isHttp) {
+      resultUrl.protocol = 'https:';
+    }
+    resultUrl.username = '';
+    resultUrl.password = '';
+    return resultUrl.href;
+  }
+
+  return href;
+}