Added proxy script

2 files changed, 46 insertions, 0 deletions

diff --git a/README b/README
index 9797a9b..7e18922 100644
--- a/README
+++ b/README
@@ -9,6 +9,18 @@ Deutschlandfunk Kalenderblatt which is only available online and as
 RSS feed but not as podcast. Requires PHP 8.
 
 
+proxy
+-----
+A very simple kind of proxy. It adds an HTTP header for Basic
+Authentication to all requests. On HTML websites all relative links
+are replaced with proxy based links.
+I use this script to embed external websites with Basic
+Authentication into my personal Nextcloud instance without the need
+to enter a password.
+Use at your own risk - this script may break security aspects and
+manipulates website content!
+
+
 rssfilter
 ---------
 A simple script to remove unwanted articles from an RSS feed, either
diff --git a/proxy/proxy.php b/proxy/proxy.php
new file mode 100644
index 0000000..3985308
--- /dev/null
+++ b/proxy/proxy.php
@@ -0,0 +1,34 @@
+<?php
+  // Secret key to use this script
+  $secret = '';
+  // HTTP authorization (USERNAME:PASSWORD Base64 encoded)
+  $authorization = '';
+
+  if (isset($_GET['secret']) && $_GET['secret'] == $secret && isset($_GET['url']) && !empty($_GET['url'])) {
+    
+    $request_headers = array('Authorization: Basic '.$authorization);
+    $url = $_GET['url'];
+ 
+    $curl = curl_init(); 
+    curl_setopt($curl, CURLOPT_URL, $url); 
+    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); 
+    curl_setopt($curl, CURLOPT_HTTPHEADER, $request_headers);
+    $content = curl_exec($curl); 
+    $contenttype = curl_getinfo($curl, CURLINFO_CONTENT_TYPE);
+    curl_close($curl);
+
+    if (str_starts_with($contenttype, 'text/html')) {
+      $proxyurl = substr($url, 0, strrpos($url, '/') + 1);
+      $scripturl = 'https://'.$_SERVER['HTTP_HOST'].$_SERVER['SCRIPT_NAME'].'?secret='.$secret.'&';
+
+      $content = preg_replace('#href="(?!https)(.+)"#i', 'href="'.$scripturl.'url='.$proxyurl.'$1"', $content);
+      $content = preg_replace('#src="(?!https)(.+)"#i', 'src="'.$scripturl.'url='.$proxyurl.'$1"', $content);
+    }
+
+    header('Content-Type: '.$contenttype);
+    echo $content;
+  
+  } else {
+    throw new Exception('Insufficient request');
+  }
+?>