Fixes to allow symbolic links, and formatting fixes

README.md

@@ -0,0 +1,71 @@
+# Gemini-PHP
+Gemini-PHP is a Gemini server written in PHP by @neil@glasgow.social.
+It's designed more for teaching than practical use.  That's said - it's very simple to get up and running and we're hosting this page on it - it seems to be performing well.
+If you have any questions or want to get in touch, you can join our community on Matrix at #gemini-php:glasgow.social
+
+## How to install
+* Download via git
+```
+git clone https://coding.openguide.co.uk/git/gemini-php/
+```
+
+* Enter the project directory and create a certificate for your server (a self signed certificate is fine, in fact it's encouraged!)
+```
+cd gemini-php
+openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365
+```
+* Combine your private key with the certificate and put in the certs directory
+
+```
+cp cert.pem certs/combined.pem
+cat key.pem >> certs/combined.pem
+```
+* Create a config file from the sample
+```
+cp config.php.sample config.php
+```
+* Then edit it with the location of your new certificate - most other options are optional
+* Start your server with
+```
+php server.php
+```
+* You should be able to visit your new server in any Gemini client (remember to open your firewall if needed - post 1965)
+
+## Using Gemini-PHP
+* The basic index file is located in hosts/default/index.gemini - edit this to get started
+* Gemini-PHP supports multiple virtual hosts, just create a directory with the name of the domain you expect to receive requests for, i.e.
+```
+mkdir hosts/glasgow.social
+mkdir hosts/projects.glasgow.social
+```
+
+## Running as a service
+To set up the server as a service, create the following file in /etc/systemd/system/gemini-php.service
+```
+[Unit]
+Description=Gemini-PHP Service
+
+[Service]
+User=gemini
+Type=simple
+TimeoutSec=0
+WorkingDirectory=/home/gemini/gemini-php/
+PIDFile=/var/run/gemini-php.pid
+ExecStart=/usr/bin/php -f /home/gemini/gemini-php/server.php
+KillMode=process
+
+Restart=on-failure
+RestartSec=42s
+
+[Install]
+WantedBy=default.target
+```
+Note, customise the above to the user you are running gemini-php as (we recommend creating a new user account for this to keep it relatively isolated) as well as the path to the script.
+Enable the script with systemctl
+```
+sudo systemctl enable gemini-php
+sudo systemctl start gemini-php
+systemctl status gemini-php
+
+sudo systemctl stop gemini-php
+```

config.php.sample

@@ -34,10 +34,8 @@ $config['certificate_passphrase'] = '';
 
 // Default index file.  If a path isn't specified then the server will
 // default to an index file (like index.html on a web server).
-//$config['default_index_file'] = "index.gemini";
+//$config['default_index_file'] = "index.gmi";
 
 // Logging, setting this to false will disable logging (default is on/true);
 //$config['logging'] = true;
 //$config['log_file'] = "logs/gemini-php.log";
-
-?>

gemini.class.php

@@ -3,30 +3,46 @@ error_reporting(E_ALL);
 set_time_limit(0);
 ob_implicit_flush();
 
-class Gemini {
+// Based on:
+// gemini://glasgow.social/gemini-php
 
+class Gemini {
 	function __construct($config) {
-		if(empty($config['certificate_file']))
-			die("Missing certificate file.  Edit config.php\n");
-		$this->ip = "0";
-		$this->port = "1965";
-		$this->data_dir = "hosts/";
-		$this->default_host_dir = "default/";
-		$this->default_index_file = "index.gemini";
+		if (empty($config['certificate_file'])) {
+			die('Missing certificate file. Edit config.php\n');
+		}
+
+		$this->ip = '0';
+		$this->port = '1965';
+		$this->data_dir = 'hosts/';
+		$this->default_host_dir = 'default/';
+		$this->default_index_file = 'index.gmi';
 		$this->logging = 1;
 		$this->log_file = "logs/gemini-php.log";
 		$this->log_sep = "\t";
-		$settings = array('ip', 'port', 'data_dir', 'default_host_dir', 'default_index_file',
-				'certificate_file', 'certificate_passphrase');
+
+		$settings = array(
+			'ip', 'port',
+			'data_dir',
+			'default_host_dir',
+			'default_index_file',
+			'certificate_file',
+			'certificate_passphrase'
+		);
+
 		foreach ($settings as $setting_key) {
-			if(!empty($config[$setting_key]))
+			if (!empty($config[$setting_key])) {
 				$this->$setting_key = $config[$setting_key];
 			}
-		// append the required filepath slashes if they're missing
-		if(substr($this->data_dir, -1) != "/")
+		}
+
+		// Append the required filepath slashes if they're missing
+		if (substr($this->data_dir, -1) != "/") {
 			$this->data_dir .= "/";
-		if(substr($this->default_host_dir, -1) != "/")
+		}
+		if (substr($this->default_host_dir, -1) != "/") {
 			$this->default_host_dir .= "/";
+		}
 		if ($this->logging) {
 			if (!file_exists($this->log_file)) {
 				$this->log_to_file("Log created", null, null, null, null);
@@ -35,12 +51,13 @@ class Gemini {
 				die("{$this->log_file} is not writable.\n");
 			}
 		}
-		if(!is_readable($this->certificate_file))
+		if (!is_readable($this->certificate_file)) {
 			die("Certificate file {$this->certificate_file} not readable.\n");
 		}
+	}
 
 	function parse_request($request) {
-		$url = trim($request); // strip <CR><LF> from the end
+		$url = trim($request); // Strip <CR><LF> from the end
 		return parse_url($url);
 	}
 
@@ -50,20 +67,28 @@ class Gemini {
 	}
 
 	function get_status_code($filepath) {
-		if(is_file($filepath) and file_exists($filepath))
-			return "20";
-		if(!file_exists($filepath))
-			return "51";
-		return "50";
+		if (is_file($filepath) and file_exists($filepath)) {
+			return '20';
+		}
+		if (!file_exists($filepath)) {
+			//echo("File $filepath doesn't exist\n");
+			return '51';
+		}
+		return '50';
 	}
 
 	function get_mime_type($filepath) {
 		$type = mime_content_type($filepath);
-		// we need a way to detect gemini file types, which PHP doesn't
+		// We need a way to detect gemini file types, which PHP doesn't
 		// so.. if it ends with gemini (or if it has no extension), assume
 		$path_parts = pathinfo($filepath);
-		if(empty($path_parts['extension']) or $path_parts['extension'] == "gemini")
-			$type = "text/gemini";
+
+		if (empty($path_parts['extension'])
+				or $path_parts['extension'] === 'gemini'
+				or $path_parts['extension'] === 'gmi'
+			) {
+			$type = 'text/gemini';
+		}
 		return $type;
 	}
 
@@ -79,31 +104,42 @@ class Gemini {
 	* @return string
 	*/
 	function get_filepath($url) {
-		$hostname = "";
-		if(!is_array($url))
+		$hostname = '';
+
+		if (!is_array($url)) {
 			return false;
-		if(!empty($url['host']))
+		}
+		if (!empty($url['host'])) {
 			$hostname = $url['host'];
+		}
 
 		$valid_hosts = $this->get_valid_hosts();
-		if(!in_array($hostname, $valid_hosts))
-			$hostname = "default";
+
+		if (!in_array($hostname, $valid_hosts)) {
+			$hostname = 'default';
+		}
 
 		// Kristall Browser is adding "__" to the end of the filenames
 		// wtf am I missing?
 		// also removing ".." to mitigate against directory traversal
-		$url['path'] = str_replace(array("..", "__"), "", $url['path']);
-		// force an index file to be appended if a filename is missing
+		$url['path'] = str_replace(array('..', '__'), '', $url['path']);
+
+		// Force an index file to be appended if a filename is missing
 		if (empty($url['path'])) {
-			$url['path'] = "/".$this->default_index_file;
-		} elseif(substr($url['path'], -1) == "/") {
+			$url['path'] = '/' . $this->default_index_file;
+		} elseif(substr($url['path'], -1) === '/') {
 			$url['path'] .= $this->default_index_file;
 		}
 
-		$valid_data_dir = dirname(__FILE__)."/".$this->data_dir;
+		$valid_data_dir = dirname(__FILE__) . '/' . $this->data_dir;
 		$return_path = $this->data_dir.$hostname.$url['path'];
-		// check the real path is in the data_dir (path traversal sanity check)
-		if(substr(realpath($return_path),0, strlen($valid_data_dir)) == $valid_data_dir) {
+
+		if (is_link($return_path)) {
+			return $return_path;
+		}
+
+		// Check the real path is in the data_dir (path traversal sanity check)
+		if (substr(realpath($return_path), 0, strlen($valid_data_dir)) === $valid_data_dir) {
 			return $return_path;
 		}
 		return false;
@@ -112,10 +148,11 @@ class Gemini {
 	function log_to_file($ip, $status_code, $meta, $filepath, $filesize) {
 		$ts = date("Y-m-d H:i:s", strtotime('now'));
 		$this->log_sep;
-		$str = $ts.$this->log_sep.$ip.$this->log_sep.$status_code.$this->log_sep.
-		$meta.$this->log_sep.$filepath.$this->log_sep.$filesize."\n";
+
+		$str = $ts.$this->log_sep . $ip . $this->log_sep
+			. $status_code . $this->log_sep
+			.	$meta.$this->log_sep . $filepath . $this->log_sep
+			. $filesize . "\n";
 		file_put_contents($this->log_file, $str, FILE_APPEND);
 	}
 }
-
-?>

hosts/default/index.gemini

@@ -1,15 +0,0 @@
-# Success!
-Your Gemini server is up and running!
-
-You can read more about this server at
-=> gemini://glasgow.social/gemini-php
-
-Join the community on Matrix at #gemini-php:glasgow.social
-
-## Getting Started
-Let's take 'gemini.com' as an example.
-* Generate a certificate and place it in the 'certs' directory named gemini.com.pem
-* Create a directory to server files from in the 'hosts' directory named gemini.com (e.g. mkdir hosts/gemini.com)
-* A file called index.gemini will be served if you haven't specified a path (this file is located at hosts/default/index.gemini)
-
-=> natalie.jpg

server.php

@@ -4,8 +4,9 @@
  * Version 0.1, Oct 2020
 */
 
-if(!require("config.php"))
+if(!require("config.php")) {
 	die("config.php is missing.  Copy config.php.sample to config.php and customise your settings");
+}
 require("gemini.class.php");
 $g = new Gemini($config);
 
@@ -25,6 +26,10 @@ $cryptoMethod = STREAM_CRYPTO_METHOD_TLS_SERVER
 	& ~ STREAM_CRYPTO_METHOD_TLSv1_0_SERVER
 	& ~ STREAM_CRYPTO_METHOD_TLSv1_1_SERVER;
 
+$cryptoMethod = STREAM_CRYPTO_METHOD_TLSv1_3_SERVER;
+
+print("Running server on port $g->port\n");
+
 while(true) {
 	$forkedSocket = stream_socket_accept($socket, "-1", $remoteIP);
 
@@ -51,8 +56,9 @@ while(true) {
 	}
 
 	$status_line = $status_code . " " . $meta;
-	if($g->logging)
+	if ($g->logging) {
 		$g->log_to_file($remoteIP, $status_code, $meta, $filepath, $filesize);
+	}
 	$status_line .= "\r\n";
 	fwrite($forkedSocket, $status_line);
 
@@ -62,5 +68,3 @@ while(true) {
 
 	fclose($forkedSocket);
 }
-
-?>