# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1476381514 -3600
# Node ID f86478a02b25713f84d84f84cf711f5c219a7e7d
# Parent  c2cf5b40b66d008e14ef735215208d6b868aa2d6
mod_http_upload_external: Add share.php example implementation

diff -r c2cf5b40b66d -r f86478a02b25 mod_http_upload_external/share.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_http_upload_external/share.php	Thu Oct 13 18:58:34 2016 +0100
@@ -0,0 +1,119 @@
+<?php
+
+/*
+  PHP script to handle file uploads and downloads for Prosody's mod_http_upload_external
+
+  Tested with Apache 2.2+ and PHP 5.3+
+
+  ** Why this script?
+
+  This script only allows uploads that have been authorized by mod_http_upload_external. It
+  attempts to make the upload/download as safe as possible, considering that there are *many*
+  security concerns involved with allowing arbitrary file upload/download on a web server.
+
+  With that said, I do not consider myself a PHP developer, and at the time of writing, this
+  code has had no external review. Use it at your own risk. I make no claims that this code
+  is secure.
+
+  ** How to use?
+
+  Drop this file somewhere it will be served by your web server. Edit the config options below.
+
+  In Prosody set:
+
+    http_upload_external_base_url = "https://your.example.com/path/to/share.php/"
+    http_upload_external_secret = "this is your secret string"
+
+  ** License
+
+  (C) 2016 Matthew Wild <mwild1@gmail.com>
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy of this software
+  and associated documentation files (the "Software"), to deal in the Software without restriction,
+  including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
+  and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
+  subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in all copies or substantial
+  portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
+  BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+  DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+*/
+
+/*\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\*/
+/*         CONFIGURATION OPTIONS                   */
+/*\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\*/
+
+/* Change this to a directory that is writable by your web server, but is outside your web root */
+$CONFIG_STORE_DIR = '/tmp';
+
+/* This must be the same as 'http_upload_external_secret' that you set in Prosody's config file */
+$CONFIG_SECRET = 'this is your secret string';
+
+/* For people who need options to tweak that they don't understand... here you are */
+$CONFIG_CHUNK_SIZE = 4096;
+
+/*\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\*/
+/*         END OF CONFIGURATION                    */
+/*\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\*/
+
+/* Do not edit below this line unless you know what you are doing (spoiler: nobody does) */
+
+$upload_file_name = substr($_SERVER['PHP_SELF'], strlen($_SERVER['SCRIPT_NAME'])+1);
+$store_file_name = $CONFIG_STORE_DIR . '/store-' . hash('sha256', $upload_file_name);
+
+$request_method = $_SERVER['REQUEST_METHOD'];
+
+if(array_key_exists('v', $_GET) === TRUE && $request_method === 'PUT') {
+	$headers = getallheaders();
+
+	$upload_file_size = $headers['Content-Length'];
+	$upload_token = $_GET['v'];
+
+	$calculated_token = hash_hmac('sha256', "$upload_file_name $upload_file_size", $CONFIG_SECRET);
+	if($upload_token !== $calculated_token) {
+		header('HTTP/1.0 403 Forbidden');
+		exit;
+	}
+
+	/* Open a file for writing */
+	$store_file = fopen($store_file_name, 'x');
+
+	if($store_file === FALSE) {
+		header('HTTP/1.0 409 Conflict');
+		exit;
+	}
+
+	/* PUT data comes in on the stdin stream */
+	$incoming_data = fopen('php://input', 'r');
+
+	/* Read the data a chunk at a time and write to the file */
+	while ($data = fread($incoming_data, $CONFIG_CHUNK_SIZE)) {
+  		fwrite($store_file, $data);
+	}
+
+	/* Close the streams */
+	fclose($incoming_data);
+	fclose($store_file);
+} else if($request_method === 'GET' || $request_method === 'HEAD') {
+	// Send file (using X-Sendfile would be nice here...)
+	if(file_exists($store_file_name)) {
+		header('Content-Disposition: attachment');
+		header('Content-Type: application/octet-stream');
+		header('Content-Length: '.filesize($store_file_name));
+		if($request_method !== 'HEAD') {
+			readfile($store_file_name);
+		}
+	} else {
+		header('HTTP/1.0 404 Not Found');
+	}
+} else {
+	header('HTTP/1.0 400 Bad Request');
+}
+
+exit;