Markdown: don't escape content + sanitize sensible tags

[github/shaarli/Shaarli.git] / application / Utils.php

diff --git a/application/Utils.php b/application/Utils.php
index 120333c560c93c29cf33a6e6175f829ae26ca6a4..868946df756d98c1a726350cd524556e48b4a667 100644 (file)
--- a/application/Utils.php
+++ b/application/Utils.php
@@ -3,6 +3,24 @@
  * Shaarli utilities
  */
 
+/**
+ * Logs a message to a text file
+ *
+ * The log format is compatible with fail2ban.
+ *
+ * @param string $logFile  where to write the logs
+ * @param string $clientIp the client's remote IPv4/IPv6 address
+ * @param string $message  the message to log
+ */
+function logm($logFile, $clientIp, $message)
+{
+    file_put_contents(
+        $logFile,
+        date('Y/m/d H:i:s').' - '.$clientIp.' - '.strval($message).PHP_EOL,
+        FILE_APPEND
+    );
+}
+
 /**
  *  Returns the small hash of a string, using RFC 4648 base64url format
  *
@@ -44,19 +62,27 @@ function endsWith($haystack, $needle, $case=true)
 }
 
 /**
- * Same as nl2br(), but escapes < and >
+ * Htmlspecialchars wrapper
+ *
+ * @param string $str the string to escape.
+ *
+ * @return string escaped.
  */
-function nl2br_escaped($html)
+function escape($str)
 {
-    return str_replace('>', '&gt;', str_replace('<', '&lt;', nl2br($html)));
+    return htmlspecialchars($str, ENT_COMPAT, 'UTF-8', false);
 }
 
 /**
- * htmlspecialchars wrapper
+ * Reverse the escape function.
+ *
+ * @param string $str the string to unescape.
+ *
+ * @return string unescaped string.
  */
-function escape($str)
+function unescape($str)
 {
-    return htmlspecialchars($str, ENT_COMPAT, 'UTF-8', false);
+    return htmlspecialchars_decode($str);
 }
 
 /**
@@ -72,12 +98,14 @@ function sanitizeLink(&$link)
 
 /**
  * Checks if a string represents a valid date
+
+ * @param string $format The expected DateTime format of the string
+ * @param string $string A string-formatted date
+ *
+ * @return bool whether the string is a valid date
  *
- * @param string        a string-formatted date
- * @param format        the expected DateTime format of the string
- * @return              whether the string is a valid date
- * @see                 http://php.net/manual/en/class.datetime.php
- * @see                 http://php.net/manual/en/datetime.createfromformat.php
+ * @see http://php.net/manual/en/class.datetime.php
+ * @see http://php.net/manual/en/datetime.createfromformat.php
  */
 function checkDateFormat($format, $string)
 {
@@ -119,26 +147,6 @@ function generateLocation($referer, $host, $loopTerms = array())
     return $finalReferer;
 }
 
-/**
- * Checks the PHP version to ensure Shaarli can run
- *
- * @param string $minVersion minimum PHP required version
- * @param string $curVersion current PHP version (use PHP_VERSION)
- *
- * @throws Exception    the PHP version is not supported
- */
-function checkPHPVersion($minVersion, $curVersion)
-{
-    if (version_compare($curVersion, $minVersion) < 0) {
-        throw new Exception(
-            'Your PHP version is obsolete!'
-            .' Shaarli requires at least PHP '.$minVersion.', and thus cannot run.'
-            .' Your PHP version has known security vulnerabilities and should be'
-            .' updated as soon as possible.'
-        );
-    }
-}
-
 /**
  * Validate session ID to prevent Full Path Disclosure.
  *
@@ -168,3 +176,56 @@ function is_session_id_valid($sessionId)
 
     return true;
 }
+
+/**
+ * In a string, converts URLs to clickable links.
+ *
+ * @param string $text       input string.
+ * @param string $redirector if a redirector is set, use it to gerenate links.
+ *
+ * @return string returns $text with all links converted to HTML links.
+ *
+ * @see Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
+ */
+function text2clickable($text, $redirector)
+{
+    $regex = '!(((?:https?|ftp|file)://|apt:|magnet:)\S+[[:alnum:]]/?)!si';
+
+    if (empty($redirector)) {
+        return preg_replace($regex, '<a href="$1">$1</a>', $text);
+    }
+    // Redirector is set, urlencode the final URL.
+    return preg_replace_callback(
+        $regex,
+        function ($matches) use ($redirector) {
+            return '<a href="' . $redirector . urlencode($matches[1]) .'">'. $matches[1] .'</a>';
+        },
+        $text
+    );
+}
+
+/**
+ * This function inserts &nbsp; where relevant so that multiple spaces are properly displayed in HTML
+ * even in the absence of <pre>  (This is used in description to keep text formatting).
+ *
+ * @param string $text input text.
+ *
+ * @return string formatted text.
+ */
+function space2nbsp($text)
+{
+    return preg_replace('/(^| ) /m', '$1&nbsp;', $text);
+}
+
+/**
+ * Format Shaarli's description
+ * TODO: Move me to ApplicationUtils when it's ready.
+ *
+ * @param string $description shaare's description.
+ * @param string $redirector  if a redirector is set, use it to gerenate links.
+ *
+ * @return string formatted description.
+ */
+function format_description($description, $redirector) {
+    return nl2br(space2nbsp(text2clickable($description, $redirector)));
+}