From 9388b856f1ad493265667bcd90e4021b692eafb2 Mon Sep 17 00:00:00 2001
From: Joshua Coales <joshua@coales.co.uk>
Date: Sat, 10 Oct 2020 00:55:00 +0100
Subject: [PATCH 1/3] [FacebookBridge] Handle mobile links and validate
 hostname the same between user and group links.

---
 bridges/FacebookBridge.php | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/bridges/FacebookBridge.php b/bridges/FacebookBridge.php
index cb5e30f82cb..9f6597fd73c 100644
--- a/bridges/FacebookBridge.php
+++ b/bridges/FacebookBridge.php
@@ -215,8 +215,7 @@ private function sanitizeGroup($group) {
 
 			$urlparts = parse_url($group);
 
-			if($urlparts['host'] !== parse_url(self::URI)['host']
-			&& 'www.' . $urlparts['host'] !== parse_url(self::URI)['host']) {
+			if(!$this->validateHost($urlparts['host'])) {
 
 				returnClientError('The host you provided is invalid! Received "'
 				. $urlparts['host']
@@ -236,6 +235,18 @@ private function sanitizeGroup($group) {
 
 	}
 
+	private function validateHost($provided_host) {
+        // Handle mobile links
+        if (strpos($provided_host, "m.") === 0) {
+            $provided_host = substr($provided_host, strlen("m."));
+        }
+
+        $facebook_host = parse_url(self::URI)['host'];
+
+        return ($provided_host !== $facebook_host
+            && 'www.' . $provided_host !== $facebook_host);
+    }
+
 	private function isPublicGroup($html) {
 
 		// Facebook redirects to the groups about page for non-public groups
@@ -348,7 +359,7 @@ private function sanitizeUser($user) {
 
 			$urlparts = parse_url($user);
 
-			if($urlparts['host'] !== parse_url(self::URI)['host']) {
+			if(!$this->validateHost($urlparts['host'])) {
 				returnClientError('The host you provided is invalid! Received "'
 				. $urlparts['host']
 				. '", expected "'

From c523c7adcbc18c8651c09d60856131d819f08806 Mon Sep 17 00:00:00 2001
From: Joshua Coales <joshua@coales.co.uk>
Date: Mon, 12 Oct 2020 16:31:54 +0100
Subject: [PATCH 2/3] [FacebookBridge] validateHost() to raise exception,
 rather than duplicating exception raising

---
 bridges/FacebookBridge.php | 28 ++++++++++------------------
 1 file changed, 10 insertions(+), 18 deletions(-)

diff --git a/bridges/FacebookBridge.php b/bridges/FacebookBridge.php
index 9f6597fd73c..1ad417a02a4 100644
--- a/bridges/FacebookBridge.php
+++ b/bridges/FacebookBridge.php
@@ -215,15 +215,7 @@ private function sanitizeGroup($group) {
 
 			$urlparts = parse_url($group);
 
-			if(!$this->validateHost($urlparts['host'])) {
-
-				returnClientError('The host you provided is invalid! Received "'
-				. $urlparts['host']
-				. '", expected "'
-				. parse_url(self::URI)['host']
-				. '"!');
-
-			}
+			$this->validateHost($urlparts['host']);
 
 			return explode('/', $urlparts['path'])[2];
 
@@ -243,8 +235,14 @@ private function validateHost($provided_host) {
 
         $facebook_host = parse_url(self::URI)['host'];
 
-        return ($provided_host !== $facebook_host
-            && 'www.' . $provided_host !== $facebook_host);
+        if ($provided_host !== $facebook_host
+            && 'www.' . $provided_host !== $facebook_host) {
+            returnClientError('The host you provided is invalid! Received "'
+                . $provided_host
+                . '", expected "'
+                . $facebook_host
+                . '"!');
+        }
     }
 
 	private function isPublicGroup($html) {
@@ -359,13 +357,7 @@ private function sanitizeUser($user) {
 
 			$urlparts = parse_url($user);
 
-			if(!$this->validateHost($urlparts['host'])) {
-				returnClientError('The host you provided is invalid! Received "'
-				. $urlparts['host']
-				. '", expected "'
-				. parse_url(self::URI)['host']
-				. '"!');
-			}
+			$this->validateHost($urlparts['host']);
 
 			if(!array_key_exists('path', $urlparts)
 			|| $urlparts['path'] === '/') {

From 84bfdb953ddac2b1a7ed6f85ff239d0f7876a995 Mon Sep 17 00:00:00 2001
From: Joshua Coales <joshua@coales.co.uk>
Date: Mon, 12 Oct 2020 17:07:00 +0100
Subject: [PATCH 3/3] [FacebookBridge] Swapping spaces for tabs

---
 bridges/FacebookBridge.php | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/bridges/FacebookBridge.php b/bridges/FacebookBridge.php
index 1ad417a02a4..b7681114d04 100644
--- a/bridges/FacebookBridge.php
+++ b/bridges/FacebookBridge.php
@@ -228,22 +228,22 @@ private function sanitizeGroup($group) {
 	}
 
 	private function validateHost($provided_host) {
-        // Handle mobile links
-        if (strpos($provided_host, "m.") === 0) {
-            $provided_host = substr($provided_host, strlen("m."));
-        }
-
-        $facebook_host = parse_url(self::URI)['host'];
-
-        if ($provided_host !== $facebook_host
-            && 'www.' . $provided_host !== $facebook_host) {
-            returnClientError('The host you provided is invalid! Received "'
-                . $provided_host
-                . '", expected "'
-                . $facebook_host
-                . '"!');
-        }
-    }
+		// Handle mobile links
+		if (strpos($provided_host, 'm.') === 0) {
+			$provided_host = substr($provided_host, strlen('m.'));
+		}
+
+		$facebook_host = parse_url(self::URI)['host'];
+
+		if ($provided_host !== $facebook_host
+			&& 'www.' . $provided_host !== $facebook_host) {
+			returnClientError('The host you provided is invalid! Received "'
+				. $provided_host
+				. '", expected "'
+				. $facebook_host
+				. '"!');
+		}
+	}
 
 	private function isPublicGroup($html) {