diff options
Diffstat (limited to 'system/libraries/Security.php')
| -rw-r--r-- | system/libraries/Security.php | 152 |
1 files changed, 78 insertions, 74 deletions
diff --git a/system/libraries/Security.php b/system/libraries/Security.php index 9a1590b5c..fa5317ea3 100644 --- a/system/libraries/Security.php +++ b/system/libraries/Security.php @@ -25,12 +25,12 @@ * @link http://codeigniter.com/user_guide/libraries/sessions.html */ class CI_Security { - var $xss_hash = ''; - var $csrf_hash = ''; + var $xss_hash = ''; + var $csrf_hash = ''; var $csrf_expire = 7200; // Two hours (in seconds) var $csrf_token_name = 'ci_csrf_token'; var $csrf_cookie_name = 'ci_csrf_token'; - + /* never allowed, string replacement */ var $never_allowed_str = array( 'document.cookie' => '[removed]', @@ -63,7 +63,7 @@ class CI_Security { } // -------------------------------------------------------------------- - + /** * Verify Cross Site Request Forgery Protection * @@ -92,7 +92,7 @@ class CI_Security { // We kill this since we're done and we don't want to polute the _POST array unset($_POST[$this->csrf_token_name]); - + // Nothing should last forever unset($_COOKIE[$this->csrf_cookie_name]); $this->_csrf_set_hash(); @@ -100,9 +100,9 @@ class CI_Security { log_message('debug', "CSRF token verified "); } - + // -------------------------------------------------------------------- - + /** * Set Cross Site Request Forgery Protection Cookie * @@ -114,12 +114,12 @@ class CI_Security { $expire = time() + $this->csrf_expire; setcookie($this->csrf_cookie_name, $this->csrf_hash, $expire, config_item('cookie_path'), config_item('cookie_domain'), 0); - - log_message('debug', "CRSF cookie Set"); + + log_message('debug', "CRSF cookie Set"); } - + // -------------------------------------------------------------------- - + /** * Set Cross Site Request Forgery Protection Cookie * @@ -146,7 +146,7 @@ class CI_Security { } // -------------------------------------------------------------------- - + /** * Show CSRF Error * @@ -159,7 +159,7 @@ class CI_Security { } // -------------------------------------------------------------------- - + /** * XSS Clean * @@ -198,7 +198,7 @@ class CI_Security { { $str[$key] = $this->xss_clean($str[$key]); } - + return $str; } @@ -210,9 +210,9 @@ class CI_Security { /* * Protect GET variables in URLs */ - + // 901119URL5918AMP18930PROTECT8198 - + $str = preg_replace('|\&([a-z\_0-9\-]+)\=([a-z\_0-9\-]+)|i', $this->xss_hash()."\\1=\\2", $str); /* @@ -225,7 +225,7 @@ class CI_Security { $str = preg_replace('#(&\#?[0-9a-z]{2,})([\x00-\x20])*;?#i', "\\1;\\2", $str); /* - * Validate UTF16 two byte encoding (x00) + * Validate UTF16 two byte encoding (x00) * * Just as above, adds a semicolon if missing. * @@ -248,9 +248,9 @@ class CI_Security { * */ $str = rawurldecode($str); - + /* - * Convert character entities to ASCII + * Convert character entities to ASCII * * This permits our tests below to work reliably. * We only convert entities that are within tags since @@ -259,14 +259,14 @@ class CI_Security { */ $str = preg_replace_callback("/[a-z]+=([\'\"]).*?\\1/si", array($this, '_convert_attribute'), $str); - + $str = preg_replace_callback("/<\w+.*?(?=>|<|$)/si", array($this, '_decode_entity'), $str); /* * Remove Invisible Characters Again! */ $str = remove_invisible_characters($str); - + /* * Convert all tabs to spaces * @@ -276,29 +276,29 @@ class CI_Security { * 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); + $str = str_replace($key, $val, $str); } - + foreach ($this->never_allowed_regex as $key => $val) { - $str = preg_replace("#".$key."#i", $val, $str); + $str = preg_replace("#".$key."#i", $val, $str); } /* @@ -321,7 +321,7 @@ class CI_Security { { $str = str_replace(array('<?', '?'.'>'), array('<?', '?>'), $str); } - + /* * Compact any exploded words * @@ -333,7 +333,7 @@ class CI_Security { foreach ($words as $word) { $temp = ''; - + for ($i = 0, $wordlen = strlen($word); $i < $wordlen; $i++) { $temp .= substr($word, $i, 1)."\s*"; @@ -343,7 +343,7 @@ class CI_Security { // 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 @@ -352,17 +352,17 @@ class CI_Security { do { $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)) { $str = preg_replace("#<(/*)(script|xss)(.*?)\>#si", '[removed]', $str); @@ -385,14 +385,14 @@ class CI_Security { if ($is_image === TRUE) { /* - * Adobe Photoshop puts XML metadata into JFIF images, including namespacing, + * 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 * @@ -420,7 +420,7 @@ class CI_Security { * */ $str = preg_replace('#(alert|cmd|passthru|eval|exec|expression|system|fopen|fsockopen|file|file_get_contents|readfile|unlink)(\s*)\((.*?)\)#si', "\\1\\2(\\3)", $str); - + /* * Final clean up * @@ -430,9 +430,9 @@ class CI_Security { */ foreach ($this->never_allowed_str as $key => $val) { - $str = str_replace($key, $val, $str); + $str = str_replace($key, $val, $str); } - + foreach ($this->never_allowed_regex as $key => $val) { $str = preg_replace("#".$key."#i", $val, $str); @@ -457,13 +457,13 @@ class CI_Security { return FALSE; } } - + log_message('debug', "XSS Filtering completed"); return $str; } // -------------------------------------------------------------------- - + /** * Random Hash for protecting URLs * @@ -471,22 +471,22 @@ class CI_Security { * @return string */ function xss_hash() - { + { if ($this->xss_hash == '') { if (phpversion() >= 4.2) mt_srand(); else mt_srand(hexdec(substr(md5(microtime()), -8)) & 0x7fffffff); - + $this->xss_hash = md5(time() + mt_rand(0, 1999999999)); } - + return $this->xss_hash; } // -------------------------------------------------------------------- - + /** * Compact Exploded Words * @@ -501,9 +501,9 @@ class CI_Security { { return preg_replace('/\s+/s', '', $matches[1]).$matches[2]; } - + // -------------------------------------------------------------------- - + /** * Sanitize Naughty HTML * @@ -517,15 +517,15 @@ class CI_Security { { // 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 * @@ -543,7 +543,7 @@ class CI_Security { $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 * @@ -563,7 +563,7 @@ class CI_Security { } // -------------------------------------------------------------------- - + /** * Attribute Conversion * @@ -577,7 +577,7 @@ class CI_Security { { return str_replace(array('>', '<', '\\'), array('>', '<', '\\\\'), $match[0]); } - + // -------------------------------------------------------------------- /** @@ -644,35 +644,35 @@ class CI_Security { function entity_decode($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 is_php('5.0.0'))) { $str = html_entity_decode($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); } - + // 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)', $str); - + // Literal Entities - Slightly slow so we do another check if (stristr($str, '&') === FALSE) { $str = strtr($str, array_flip(get_html_translation_table(HTML_ENTITIES))); } - + return $str; } - + // -------------------------------------------------------------------- - + /** * Filename Security * @@ -680,11 +680,10 @@ class CI_Security { * @param string * @return string */ - function sanitize_filename($str) + function sanitize_filename($str, $relative_path = FALSE) { $bad = array( "../", - "./", "<!--", "-->", "<", @@ -701,22 +700,27 @@ class CI_Security { '=', ';', '?', - '/', "%20", "%22", "%3c", // < - "%253c", // < - "%3e", // > - "%0e", // > - "%28", // ( - "%29", // ) - "%2528", // ( - "%26", // & - "%24", // $ - "%3f", // ? - "%3b", // ; + "%253c", // < + "%3e", // > + "%0e", // > + "%28", // ( + "%29", // ) + "%2528", // ( + "%26", // & + "%24", // $ + "%3f", // ? + "%3b", // ; "%3d" // = ); + + if ( ! $relative_path) + { + $bad[] = './'; + $bad[] = '/'; + } return stripslashes(str_replace($bad, '', $str)); } |