diff options
| -rw-r--r-- | system/core/Input.php | 897 |
1 files changed, 192 insertions, 705 deletions
diff --git a/system/core/Input.php b/system/core/Input.php index 51c12a8a0..0760dc830 100644 --- a/system/core/Input.php +++ b/system/core/Input.php @@ -27,31 +27,14 @@ * @link http://codeigniter.com/user_guide/libraries/input.html */ class CI_Input { - var $use_xss_clean = FALSE; - var $xss_hash = ''; - var $ip_address = FALSE; - var $user_agent = FALSE; - var $allow_get_array = FALSE; - - /* never allowed, string replacement */ - var $never_allowed_str = array( - 'document.cookie' => '[removed]', - 'document.write' => '[removed]', - '.parentNode' => '[removed]', - '.innerHTML' => '[removed]', - 'window.location' => '[removed]', - '-moz-binding' => '[removed]', - '<!--' => '<!--', - '-->' => '-->', - '<![CDATA[' => '<![CDATA[' - ); - /* never allowed, regex replacement */ - var $never_allowed_regex = array( - "javascript\s*:" => '[removed]', - "expression\s*(\(|&\#40;)" => '[removed]', // CSS and IE - "vbscript\s*:" => '[removed]', // IE, surprise! - "Redirect\s+302" => '[removed]' - ); + + var $ip_address = FALSE; + var $user_agent = FALSE; + var $_allow_get_array = FALSE; + var $_standardize_newlines = TRUE; + var $_enable_xss = FALSE; // Set automatically based on config setting + var $_enable_csrf = FALSE; // Set automatically based on config setting + /** * Constructor @@ -65,161 +48,25 @@ class CI_Input { { log_message('debug', "Input Class Initialized"); - $CFG =& load_class('Config'); - $this->use_xss_clean = ($CFG->item('global_xss_filtering') === TRUE) ? TRUE : FALSE; - $this->allow_get_array = ($CFG->item('enable_query_strings') === TRUE) ? TRUE : FALSE; - $this->_sanitize_globals(); - } - - // -------------------------------------------------------------------- - - /** - * Sanitize Globals - * - * This function does the following: - * - * Unsets $_GET data (if query strings are not enabled) - * - * Unsets all globals if register_globals is enabled - * - * Standardizes newline characters to \n - * - * @access private - * @return void - */ - function _sanitize_globals() - { - // Would kind of be "wrong" to unset any of these GLOBALS - $protected = array('_SERVER', '_GET', '_POST', '_FILES', '_REQUEST', '_SESSION', '_ENV', 'GLOBALS', 'HTTP_RAW_POST_DATA', - 'system_folder', 'application_folder', 'BM', 'EXT', 'CFG', 'URI', 'RTR', 'OUT', 'IN'); - - // Unset globals for security. - // This is effectively the same as register_globals = off - foreach (array($_GET, $_POST, $_COOKIE, $_SERVER, $_FILES, $_ENV, (isset($_SESSION) && is_array($_SESSION)) ? $_SESSION : array()) as $global) - { - if ( ! is_array($global)) - { - if ( ! in_array($global, $protected)) - { - unset($GLOBALS[$global]); - } - } - else - { - foreach ($global as $key => $val) - { - if ( ! in_array($key, $protected)) - { - unset($GLOBALS[$key]); - } - - if (is_array($val)) - { - foreach($val as $k => $v) - { - if ( ! in_array($k, $protected)) - { - unset($GLOBALS[$k]); - } - } - } - } - } - } - - // Is $_GET data allowed? If not we'll set the $_GET to an empty array - if ($this->allow_get_array == FALSE) - { - $_GET = array(); - } - else - { - $_GET = $this->_clean_input_data($_GET); - } - - // Clean $_POST Data - $_POST = $this->_clean_input_data($_POST); - - // Clean $_COOKIE Data - // Also get rid of specially treated cookies that might be set by a server - // or silly application, that are of no use to a CI application anyway - // but that when present will trip our 'Disallowed Key Characters' alarm - // http://www.ietf.org/rfc/rfc2109.txt - // note that the key names below are single quoted strings, and are not PHP variables - unset($_COOKIE['$Version']); - unset($_COOKIE['$Path']); - unset($_COOKIE['$Domain']); - $_COOKIE = $this->_clean_input_data($_COOKIE); - - log_message('debug', "Global POST and COOKIE data sanitized"); - } - - // -------------------------------------------------------------------- - - /** - * Clean Input Data - * - * This is a helper function. It escapes data and - * standardizes newline characters to \n - * - * @access private - * @param string - * @return string - */ - function _clean_input_data($str) - { - if (is_array($str)) - { - $new_array = array(); - foreach ($str as $key => $val) - { - $new_array[$this->_clean_input_keys($key)] = $this->_clean_input_data($val); - } - return $new_array; - } - - // We strip slashes if magic quotes is on to keep things consistent - if (get_magic_quotes_gpc()) - { - $str = stripslashes($str); - } + $this->_allow_get_array = (config_item('enable_query_strings') === TRUE) ? TRUE : FALSE; + $this->_enable_xss = (config_item('global_xss_filtering') === TRUE) ? TRUE : FALSE; + $this->_enable_csrf = (config_item('csrf_protection') === TRUE) ? TRUE : FALSE; - // Should we filter the input data? - if ($this->use_xss_clean === TRUE) + // Do we need to load the security class? + if ($this->_enable_xss == TRUE OR $this->_enable_csrf == TRUE) { - $str = $this->xss_clean($str); + $this->security =& load_class('Security'); } - // Standardize newlines - if (strpos($str, "\r") !== FALSE) + // Do we need the Unicode class? + if (UTF8_ENABLED === TRUE) { - $str = str_replace(array("\r\n", "\r"), "\n", $str); + global $UNI; + $this->uni =& $UNI; } - return $str; - } - - // -------------------------------------------------------------------- - - /** - * Clean Keys - * - * This is a helper function. To prevent malicious users - * from trying to exploit keys we make sure that keys are - * only named with alpha-numeric text and a few other items. - * - * @access private - * @param string - * @return string - */ - function _clean_input_keys($str) - { - if ( ! preg_match("/^[a-z0-9:_\/-]+$/i", $str)) - { - exit('Disallowed Key Characters.'); - } - - return $str; + // Sanitize global arrays + $this->_sanitize_globals(); } // -------------------------------------------------------------------- @@ -244,7 +91,8 @@ class CI_Input { if ($xss_clean === TRUE) { - return $this->xss_clean($array[$index]); + $_security =& load_class('Security'); + return $_security->xss_clean($array[$index]); } return $array[$index]; @@ -280,6 +128,7 @@ class CI_Input { return $this->_fetch_from_array($_POST, $index, $xss_clean); } + // -------------------------------------------------------------------- /** @@ -317,6 +166,68 @@ class CI_Input { return $this->_fetch_from_array($_COOKIE, $index, $xss_clean); } + // ------------------------------------------------------------------------ + + /** + * Set cookie + * + * Accepts six parameter, or you can submit an associative + * array in the first parameter containing all the values. + * + * @access public + * @param mixed + * @param string the value of the cookie + * @param string the number of seconds until expiration + * @param string the cookie domain. Usually: .yourdomain.com + * @param string the cookie path + * @param string the cookie prefix + * @return void + */ + function set_cookie($name = '', $value = '', $expire = '', $domain = '', $path = '/', $prefix = '') + { + if (is_array($name)) + { + foreach (array('value', 'expire', 'domain', 'path', 'prefix', 'name') as $item) + { + if (isset($name[$item])) + { + $$item = $name[$item]; + } + } + } + + if ($prefix == '' AND config_item('cookie_prefix') != '') + { + $prefix = config_item('cookie_prefix'); + } + if ($domain == '' AND config_item('cookie_domain') != '') + { + $domain = config_item('cookie_domain'); + } + if ($path == '/' AND config_item('cookie_path') != '/') + { + $path = config_item('cookie_path'); + } + + if ( ! is_numeric($expire)) + { + $expire = time() - 86500; + } + else + { + if ($expire > 0) + { + $expire = time() + $expire; + } + else + { + $expire = 0; + } + } + + setcookie($prefix.$name, $value, $expire, $path, $domain, 0); + } + // -------------------------------------------------------------------- /** @@ -453,580 +364,155 @@ class CI_Input { // -------------------------------------------------------------------- /** - * Filename Security - * - * @access public - * @param string - * @return string - */ - function filename_security($str) - { - $bad = array( - "../", - "./", - "<!--", - "-->", - "<", - ">", - "'", - '"', - '&', - '$', - '#', - '{', - '}', - '[', - ']', - '=', - ';', - '?', - "%20", - "%22", - "%3c", // < - "%253c", // < - "%3e", // > - "%0e", // > - "%28", // ( - "%29", // ) - "%2528", // ( - "%26", // & - "%24", // $ - "%3f", // ? - "%3b", // ; - "%3d" // = - ); - - return stripslashes(str_replace($bad, '', $str)); - } - - // -------------------------------------------------------------------- - - /** - * XSS Clean + * Sanitize Globals * - * Sanitizes data so that Cross Site Scripting Hacks can be - * prevented. This function does a fair amount of work but - * it is extremely thorough, designed to prevent even the - * most obscure XSS attempts. Nothing is ever 100% foolproof, - * of course, but I haven't been able to get anything passed - * the filter. + * This function does the following: * - * Note: This function should only be used to deal with data - * upon submission. It's not something that should - * be used for general runtime processing. + * Unsets $_GET data (if query strings are not enabled) * - * This function was based in part on some code and ideas I - * got from Bitflux: http://blog.bitflux.ch/wiki/XSS_Prevention + * Unsets all globals if register_globals is enabled * - * To help develop this script I used this great list of - * vulnerabilities along with a few other hacks I've - * harvested from examining vulnerabilities in other programs: - * http://ha.ckers.org/xss.html + * Standardizes newline characters to \n * - * @access public - * @param string - * @return string + * @access private + * @return void */ - function xss_clean($str, $is_image = FALSE) + function _sanitize_globals() { - /* - * Is the string an array? - * - */ - if (is_array($str)) + // It would be "wrong" to unset any of these GLOBALS. + $protected = array('_SERVER', '_GET', '_POST', '_FILES', '_REQUEST', '_SESSION', '_ENV', 'GLOBALS', 'HTTP_RAW_POST_DATA', + 'system_folder', 'application_folder', 'BM', 'EXT', 'CFG', 'URI', 'RTR', 'OUT', 'IN'); + + // Unset globals for securiy. + // This is effectively the same as register_globals = off + foreach (array($_GET, $_POST, $_COOKIE) as $global) { - while (list($key) = each($str)) + if ( ! is_array($global)) { - $str[$key] = $this->xss_clean($str[$key]); + if ( ! in_array($global, $protected)) + { + global $$global; + $$global = NULL; + } + } + else + { + foreach ($global as $key => $val) + { + if ( ! in_array($key, $protected)) + { + global $$key; + $$key = NULL; + } + } } - - return $str; - } - - /* - * Remove Invisible Characters - */ - $str = $this->_remove_invisible_characters($str); - - /* - * Protect GET variables in URLs - */ - - // 901119URL5918AMP18930PROTECT8198 - - $str = preg_replace('|\&([a-z\_0-9\-]+)\=([a-z\_0-9\-]+)|i', $this->xss_hash()."\\1=\\2", $str); - - /* - * Validate standard character entities - * - * Add a semicolon if missing. We do this to enable - * the conversion of entities to ASCII later. - * - */ - $str = preg_replace('#(&\#?[0-9a-z]{2,})([\x00-\x20])*;?#i', "\\1;\\2", $str); - - /* - * Validate UTF16 two byte encoding (x00) - * - * Just as above, adds a semicolon if missing. - * - */ - $str = preg_replace('#(&\#x?)([0-9A-F]+);?#i',"\\1\\2;",$str); - - /* - * Un-Protect GET variables in URLs - */ - $str = str_replace($this->xss_hash(), '&', $str); - - /* - * URL Decode - * - * Just in case stuff like this is submitted: - * - * <a href="http://%77%77%77%2E%67%6F%6F%67%6C%65%2E%63%6F%6D">Google</a> - * - * Note: Use rawurldecode() so it does not remove plus signs - * - */ - $str = rawurldecode($str); - - /* - * Convert character entities to ASCII - * - * This permits our tests below to work reliably. - * We only convert entities that are within tags since - * these are the ones that will pose security problems. - * - */ - - $str = preg_replace_callback("/[a-z]+=([\'\"]).*?\\1/si", array($this, '_convert_attribute'), $str); - - $str = preg_replace_callback("/<\w+.*?(?=>|<|$)/si", array($this, '_html_entity_decode_callback'), $str); - - /* - * Remove Invisible Characters Again! - */ - $str = $this->_remove_invisible_characters($str); - - /* - * Convert all tabs to spaces - * - * This prevents strings like this: ja vascript - * NOTE: we deal with spaces between characters later. - * NOTE: preg_replace was found to be amazingly slow here on large blocks of data, - * so we use str_replace. - * - */ - - if (strpos($str, "\t") !== FALSE) - { - $str = str_replace("\t", ' ', $str); - } - - /* - * Capture converted string for later comparison - */ - $converted_string = $str; - - /* - * Not Allowed Under Any Conditions - */ - - foreach ($this->never_allowed_str as $key => $val) - { - $str = str_replace($key, $val, $str); - } - - foreach ($this->never_allowed_regex as $key => $val) - { - $str = preg_replace("#".$key."#i", $val, $str); } - /* - * Makes PHP tags safe - * - * Note: XML tags are inadvertently replaced too: - * - * <?xml - * - * But it doesn't seem to pose a problem. - * - */ - if ($is_image === TRUE) + // Is $_GET data allowed? If not we'll set the $_GET to an empty array + if ($this->_allow_get_array == FALSE) { - // Images have a tendency to have the PHP short opening and closing tags every so often - // so we skip those and only do the long opening tags. - $str = preg_replace('/<\?(php)/i', "<?\\1", $str); + $_GET = array(); } else { - $str = str_replace(array('<?', '?'.'>'), array('<?', '?>'), $str); - } - - /* - * Compact any exploded words - * - * This corrects words like: j a v a s c r i p t - * These words are compacted back to their correct state. - * - */ - $words = array('javascript', 'expression', 'vbscript', 'script', 'applet', 'alert', 'document', 'write', 'cookie', 'window'); - foreach ($words as $word) - { - $temp = ''; - - for ($i = 0, $wordlen = strlen($word); $i < $wordlen; $i++) + if (is_array($_GET) AND count($_GET) > 0) { - $temp .= substr($word, $i, 1)."\s*"; + foreach($_GET as $key => $val) + { + $_GET[$this->_clean_input_keys($key)] = $this->_clean_input_data($val); + } } - - // We only want to do this when it is followed by a non-word character - // That way valid stuff like "dealer to" does not become "dealerto" - $str = preg_replace_callback('#('.substr($temp, 0, -3).')(\W)#is', array($this, '_compact_exploded_words'), $str); } - /* - * Remove disallowed Javascript in links or img tags - * We used to do some version comparisons and use of stripos for PHP5, but it is dog slow compared - * to these simplified non-capturing preg_match(), especially if the pattern exists in the string - */ - do + // Clean $_POST Data + if (is_array($_POST) AND count($_POST) > 0) { - $original = $str; - - if (preg_match("/<a/i", $str)) - { - $str = preg_replace_callback("#<a\s+([^>]*?)(>|$)#si", array($this, '_js_link_removal'), $str); - } - - if (preg_match("/<img/i", $str)) - { - $str = preg_replace_callback("#<img\s+([^>]*?)(\s?/?>|$)#si", array($this, '_js_img_removal'), $str); - } - - if (preg_match("/script/i", $str) OR preg_match("/xss/i", $str)) + foreach($_POST as $key => $val) { - $str = preg_replace("#<(/*)(script|xss)(.*?)\>#si", '[removed]', $str); + $_POST[$this->_clean_input_keys($key)] = $this->_clean_input_data($val); } } - while($original != $str); - - unset($original); - - /* - * Remove JavaScript Event Handlers - * - * Note: This code is a little blunt. It removes - * the event handler and anything up to the closing >, - * but it's unlikely to be a problem. - * - */ - $event_handlers = array('[^a-z_\-]on\w*','xmlns'); - - if ($is_image === TRUE) - { - /* - * Adobe Photoshop puts XML metadata into JFIF images, including namespacing, - * so we have to allow this for images. -Paul - */ - unset($event_handlers[array_search('xmlns', $event_handlers)]); - } - - $str = preg_replace("#<([^><]+?)(".implode('|', $event_handlers).")(\s*=\s*[^><]*)([><]*)#i", "<\\1\\4", $str); - - /* - * Sanitize naughty HTML elements - * - * If a tag containing any of the words in the list - * below is found, the tag gets converted to entities. - * - * So this: <blink> - * Becomes: <blink> - * - */ - $naughty = 'alert|applet|audio|basefont|base|behavior|bgsound|blink|body|embed|expression|form|frameset|frame|head|html|ilayer|iframe|input|isindex|layer|link|meta|object|plaintext|style|script|textarea|title|video|xml|xss'; - $str = preg_replace_callback('#<(/*\s*)('.$naughty.')([^><]*)([><]*)#is', array($this, '_sanitize_naughty_html'), $str); - - /* - * Sanitize naughty scripting elements - * - * Similar to above, only instead of looking for - * tags it looks for PHP and JavaScript commands - * that are disallowed. Rather than removing the - * code, it simply converts the parenthesis to entities - * rendering the code un-executable. - * - * For example: eval('some code') - * Becomes: eval('some code') - * - */ - $str = preg_replace('#(alert|cmd|passthru|eval|exec|expression|system|fopen|fsockopen|file|file_get_contents|readfile|unlink)(\s*)\((.*?)\)#si', "\\1\\2(\\3)", $str); - - /* - * Final clean up - * - * This adds a bit of extra precaution in case - * something got through the above filters - * - */ - foreach ($this->never_allowed_str as $key => $val) - { - $str = str_replace($key, $val, $str); - } - - foreach ($this->never_allowed_regex as $key => $val) - { - $str = preg_replace("#".$key."#i", $val, $str); - } - - /* - * Images are Handled in a Special Way - * - Essentially, we want to know that after all of the character conversion is done whether - * any unwanted, likely XSS, code was found. If not, we return TRUE, as the image is clean. - * However, if the string post-conversion does not matched the string post-removal of XSS, - * then it fails, as there was unwanted XSS code found and removed/changed during processing. - */ - if ($is_image === TRUE) - { - if ($str == $converted_string) - { - return TRUE; - } - else + // Clean $_COOKIE Data + if (is_array($_COOKIE) AND count($_COOKIE) > 0) + { + // Also get rid of specially treated cookies that might be set by a server + // or silly application, that are of no use to a CI application anyway + // but that when present will trip our 'Disallowed Key Characters' alarm + // http://www.ietf.org/rfc/rfc2109.txt + // note that the key names below are single quoted strings, and are not PHP variables + unset($_COOKIE['$Version']); + unset($_COOKIE['$Path']); + unset($_COOKIE['$Domain']); + + foreach($_COOKIE as $key => $val) { - return FALSE; + $_COOKIE[$this->_clean_input_keys($key)] = $this->_clean_input_data($val); } } - log_message('debug', "XSS Filtering completed"); - return $str; - } + // Sanitize PHP_SELF + $_SERVER['PHP_SELF'] = strip_tags($_SERVER['PHP_SELF']); - // -------------------------------------------------------------------- - /** - * Random Hash for protecting URLs - * - * @access public - * @return string - */ - function xss_hash() - { - if ($this->xss_hash == '') + // CSRF Protection check + if ($this->_enable_csrf == TRUE) { - if (phpversion() >= 4.2) - mt_srand(); - else - mt_srand(hexdec(substr(md5(microtime()), -8)) & 0x7fffffff); - - $this->xss_hash = md5(time() + mt_rand(0, 1999999999)); + $this->security->csrf_verify(); } - return $this->xss_hash; + log_message('debug', "Global POST and COOKIE data sanitized"); } // -------------------------------------------------------------------- /** - * Remove Invisible Characters + * Clean Input Data * - * This prevents sandwiching null characters - * between ascii characters, like Java\0script. + * This is a helper function. It escapes data and + * standardizes newline characters to \n * - * @access public + * @access private * @param string * @return string */ - function _remove_invisible_characters($str) + function _clean_input_data($str) { - static $non_displayables; - - if ( ! isset($non_displayables)) + if (is_array($str)) { - // every control character except newline (dec 10), carriage return (dec 13), and horizontal tab (dec 09), - $non_displayables = array( - '/%0[0-8bcef]/', // url encoded 00-08, 11, 12, 14, 15 - '/%1[0-9a-f]/', // url encoded 16-31 - '/[\x00-\x08]/', // 00-08 - '/\x0b/', '/\x0c/', // 11, 12 - '/[\x0e-\x1f]/' // 14-31 - ); + $new_array = array(); + foreach ($str as $key => $val) + { + $new_array[$this->_clean_input_keys($key)] = $this->_clean_input_data($val); + } + return $new_array; } - do + // We strip slashes if magic quotes is on to keep things consistent + if (get_magic_quotes_gpc()) { - $cleaned = $str; - $str = preg_replace($non_displayables, '', $str); + $str = stripslashes($str); } - while ($cleaned != $str); - - return $str; - } - - // -------------------------------------------------------------------- - - /** - * Compact Exploded Words - * - * Callback function for xss_clean() to remove whitespace from - * things like j a v a s c r i p t - * - * @access public - * @param type - * @return type - */ - function _compact_exploded_words($matches) - { - return preg_replace('/\s+/s', '', $matches[1]).$matches[2]; - } - - // -------------------------------------------------------------------- - - /** - * Sanitize Naughty HTML - * - * Callback function for xss_clean() to remove naughty HTML elements - * - * @access private - * @param array - * @return string - */ - function _sanitize_naughty_html($matches) - { - // encode opening brace - $str = '<'.$matches[1].$matches[2].$matches[3]; - - // encode captured opening or closing brace to prevent recursive vectors - $str .= str_replace(array('>', '<'), array('>', '<'), $matches[4]); - - return $str; - } - - // -------------------------------------------------------------------- - - /** - * JS Link Removal - * - * Callback function for xss_clean() to sanitize links - * This limits the PCRE backtracks, making it more performance friendly - * and prevents PREG_BACKTRACK_LIMIT_ERROR from being triggered in - * PHP 5.2+ on link-heavy strings - * - * @access private - * @param array - * @return string - */ - function _js_link_removal($match) - { - $attributes = $this->_filter_attributes(str_replace(array('<', '>'), '', $match[1])); - return str_replace($match[1], preg_replace("#href=.*?(alert\(|alert&\#40;|javascript\:|charset\=|window\.|document\.|\.cookie|<script|<xss|base64\s*,)#si", "", $attributes), $match[0]); - } - - /** - * JS Image Removal - * - * Callback function for xss_clean() to sanitize image tags - * This limits the PCRE backtracks, making it more performance friendly - * and prevents PREG_BACKTRACK_LIMIT_ERROR from being triggered in - * PHP 5.2+ on image tag heavy strings - * - * @access private - * @param array - * @return string - */ - function _js_img_removal($match) - { - $attributes = $this->_filter_attributes(str_replace(array('<', '>'), '', $match[1])); - return str_replace($match[1], preg_replace("#src=.*?(alert\(|alert&\#40;|javascript\:|charset\=|window\.|document\.|\.cookie|<script|<xss|base64\s*,)#si", "", $attributes), $match[0]); - } - - // -------------------------------------------------------------------- - - /** - * Attribute Conversion - * - * Used as a callback for XSS Clean - * - * @access public - * @param array - * @return string - */ - function _convert_attribute($match) - { - return str_replace(array('>', '<', '\\'), array('>', '<', '\\\\'), $match[0]); - } - - // -------------------------------------------------------------------- - /** - * HTML Entity Decode Callback - * - * Used as a callback for XSS Clean - * - * @access public - * @param array - * @return string - */ - function _html_entity_decode_callback($match) - { - $CFG =& load_class('Config'); - $charset = $CFG->item('charset'); - - return $this->_html_entity_decode($match[0], strtoupper($charset)); - } - - // -------------------------------------------------------------------- - - /** - * HTML Entities Decode - * - * This function is a replacement for html_entity_decode() - * - * In some versions of PHP the native function does not work - * when UTF-8 is the specified character set, so this gives us - * a work-around. More info here: - * http://bugs.php.net/bug.php?id=25670 - * - * @access private - * @param string - * @param string - * @return string - */ - /* ------------------------------------------------- - /* Replacement for html_entity_decode() - /* -------------------------------------------------*/ - - /* - NOTE: html_entity_decode() has a bug in some PHP versions when UTF-8 is the - character set, and the PHP developers said they were not back porting the - fix to versions other than PHP 5.x. - */ - function _html_entity_decode($str, $charset='UTF-8') - { - if (stristr($str, '&') === FALSE) return $str; - - // The reason we are not using html_entity_decode() by itself is because - // while it is not technically correct to leave out the semicolon - // at the end of an entity most browsers will still interpret the entity - // correctly. html_entity_decode() does not convert entities without - // semicolons, so we are left with our own little solution here. Bummer. - - if (function_exists('html_entity_decode') && (strtolower($charset) != 'utf-8' OR version_compare(phpversion(), '5.0.0', '>='))) + // Clean UTF-8 if supported + if (UTF8_ENABLED === TRUE) { - $str = html_entity_decode($str, ENT_COMPAT, $charset); - $str = preg_replace('~&#x(0*[0-9a-f]{2,5})~ei', 'chr(hexdec("\\1"))', $str); - return preg_replace('~&#([0-9]{2,4})~e', 'chr(\\1)', $str); + $str = $this->uni->clean_string($str); } - // Numeric Entities - $str = preg_replace('~&#x(0*[0-9a-f]{2,5});{0,1}~ei', 'chr(hexdec("\\1"))', $str); - $str = preg_replace('~&#([0-9]{2,4});{0,1}~e', 'chr(\\1)', $str); + // Should we filter the input data? + if ($this->_enable_xss === TRUE) + { + $str = $this->security->xss_clean($str); + } - // Literal Entities - Slightly slow so we do another check - if (stristr($str, '&') === FALSE) + // Standardize newlines if needed + if ($this->_standardize_newlines == TRUE) { - $str = strtr($str, array_flip(get_html_translation_table(HTML_ENTITIES))); + if (strpos($str, "\r") !== FALSE) + { + $str = str_replace(array("\r\n", "\r"), "\n", $str); + } } return $str; @@ -1035,31 +521,32 @@ class CI_Input { // -------------------------------------------------------------------- /** - * Filter Attributes + * Clean Keys * - * Filters tag attributes for consistency and safety + * This is a helper function. To prevent malicious users + * from trying to exploit keys we make sure that keys are + * only named with alpha-numeric text and a few other items. * - * @access public + * @access private * @param string * @return string */ - function _filter_attributes($str) + function _clean_input_keys($str) { - $out = ''; + if ( ! preg_match("/^[a-z0-9:_\/-]+$/i", $str)) + { + exit('Disallowed Key Characters.'); + } - if (preg_match_all('#\s*[a-z\-]+\s*=\s*(\042|\047)([^\\1]*?)\\1#is', $str, $matches)) + // Clean UTF-8 if supported + if (UTF8_ENABLED === TRUE) { - foreach ($matches[0] as $match) - { - $out .= preg_replace("#/\*.*?\*/#s", '', $match); - } + $str = $this->uni->clean_string($str); } - return $out; + return $str; } - // -------------------------------------------------------------------- - } // END Input class |