application/Utils.php

   1 <?php
   2 /**
   3  * Shaarli utilities
   4  */
   5
   6 /**
   7  * Logs a message to a text file
   8  *
   9  * The log format is compatible with fail2ban.
  10  *
  11  * @param string $logFile  where to write the logs
  12  * @param string $clientIp the client's remote IPv4/IPv6 address
  13  * @param string $message  the message to log
  14  */
  15 function logm($logFile, $clientIp, $message)
  16 {
  17     file_put_contents(
  18         $logFile,
  19         date('Y/m/d H:i:s').' - '.$clientIp.' - '.strval($message).PHP_EOL,
  20         FILE_APPEND
  21     );
  22 }
  23
  24 /**
  25  *  Returns the small hash of a string, using RFC 4648 base64url format
  26  *
  27  *  Small hashes:
  28  *   - are unique (well, as unique as crc32, at last)
  29  *   - are always 6 characters long.
  30  *   - only use the following characters: a-z A-Z 0-9 - _ @
  31  *   - are NOT cryptographically secure (they CAN be forged)
  32  *
  33  *  In Shaarli, they are used as a tinyurl-like link to individual entries,
  34  *  built once with the combination of the date and item ID.
  35  *  e.g. smallHash('20111006_131924' . 142) --> eaWxtQ
  36  *
  37  * @warning before v0.8.1, smallhashes were built only with the date,
  38  *          and their value has been preserved.
  39  *
  40  * @param string $text Create a hash from this text.
  41  *
  42  * @return string generated small hash.
  43  */
  44 function smallHash($text)
  45 {
  46     $t = rtrim(base64_encode(hash('crc32', $text, true)), '=');
  47     return strtr($t, '+/', '-_');
  48 }
  49
  50 /**
  51  * Tells if a string start with a substring
  52  *
  53  * @param string $haystack Given string.
  54  * @param string $needle   String to search at the beginning of $haystack.
  55  * @param bool   $case     Case sensitive.
  56  *
  57  * @return bool True if $haystack starts with $needle.
  58  */
  59 function startsWith($haystack, $needle, $case = true)
  60 {
  61     if ($case) {
  62         return (strcmp(substr($haystack, 0, strlen($needle)), $needle) === 0);
  63     }
  64     return (strcasecmp(substr($haystack, 0, strlen($needle)), $needle) === 0);
  65 }
  66
  67 /**
  68  * Tells if a string ends with a substring
  69  *
  70  * @param string $haystack Given string.
  71  * @param string $needle   String to search at the end of $haystack.
  72  * @param bool   $case     Case sensitive.
  73  *
  74  * @return bool True if $haystack ends with $needle.
  75  */
  76 function endsWith($haystack, $needle, $case = true)
  77 {
  78     if ($case) {
  79         return (strcmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0);
  80     }
  81     return (strcasecmp(substr($haystack, strlen($haystack) - strlen($needle)), $needle) === 0);
  82 }
  83
  84 /**
  85  * Htmlspecialchars wrapper
  86  * Support multidimensional array of strings.
  87  *
  88  * @param mixed $input Data to escape: a single string or an array of strings.
  89  *
  90  * @return string escaped.
  91  */
  92 function escape($input)
  93 {
  94     if (is_bool($input)) {
  95         return $input;
  96     }
  97
  98     if (is_array($input)) {
  99         $out = array();
 100         foreach($input as $key => $value) {
 101             $out[$key] = escape($value);
 102         }
 103         return $out;
 104     }
 105     return htmlspecialchars($input, ENT_COMPAT, 'UTF-8', false);
 106 }
 107
 108 /**
 109  * Reverse the escape function.
 110  *
 111  * @param string $str the string to unescape.
 112  *
 113  * @return string unescaped string.
 114  */
 115 function unescape($str)
 116 {
 117     return htmlspecialchars_decode($str);
 118 }
 119
 120 /**
 121  * Sanitize link before rendering.
 122  *
 123  * @param array $link Link to escape.
 124  */
 125 function sanitizeLink(&$link)
 126 {
 127     $link['url'] = escape($link['url']); // useful?
 128     $link['title'] = escape($link['title']);
 129     $link['description'] = escape($link['description']);
 130     $link['tags'] = escape($link['tags']);
 131 }
 132
 133 /**
 134  * Checks if a string represents a valid date
 135
 136  * @param string $format The expected DateTime format of the string
 137  * @param string $string A string-formatted date
 138  *
 139  * @return bool whether the string is a valid date
 140  *
 141  * @see http://php.net/manual/en/class.datetime.php
 142  * @see http://php.net/manual/en/datetime.createfromformat.php
 143  */
 144 function checkDateFormat($format, $string)
 145 {
 146     $date = DateTime::createFromFormat($format, $string);
 147     return $date && $date->format($string) == $string;
 148 }
 149
 150 /**
 151  * Generate a header location from HTTP_REFERER.
 152  * Make sure the referer is Shaarli itself and prevent redirection loop.
 153  *
 154  * @param string $referer - HTTP_REFERER.
 155  * @param string $host - Server HOST.
 156  * @param array $loopTerms - Contains list of term to prevent redirection loop.
 157  *
 158  * @return string $referer - final referer.
 159  */
 160 function generateLocation($referer, $host, $loopTerms = array())
 161 {
 162     $finalReferer = '?';
 163
 164     // No referer if it contains any value in $loopCriteria.
 165     foreach ($loopTerms as $value) {
 166         if (strpos($referer, $value) !== false) {
 167             return $finalReferer;
 168         }
 169     }
 170
 171     // Remove port from HTTP_HOST
 172     if ($pos = strpos($host, ':')) {
 173         $host = substr($host, 0, $pos);
 174     }
 175
 176     $refererHost = parse_url($referer, PHP_URL_HOST);
 177     if (!empty($referer) && (strpos($refererHost, $host) !== false || startsWith('?', $refererHost))) {
 178         $finalReferer = $referer;
 179     }
 180
 181     return $finalReferer;
 182 }
 183
 184 /**
 185  * Validate session ID to prevent Full Path Disclosure.
 186  *
 187  * See #298.
 188  * The session ID's format depends on the hash algorithm set in PHP settings
 189  *
 190  * @param string $sessionId Session ID
 191  *
 192  * @return true if valid, false otherwise.
 193  *
 194  * @see http://php.net/manual/en/function.hash-algos.php
 195  * @see http://php.net/manual/en/session.configuration.php
 196  */
 197 function is_session_id_valid($sessionId)
 198 {
 199     if (empty($sessionId)) {
 200         return false;
 201     }
 202
 203     if (!$sessionId) {
 204         return false;
 205     }
 206
 207     if (!preg_match('/^[a-zA-Z0-9,-]{2,128}$/', $sessionId)) {
 208         return false;
 209     }
 210
 211     return true;
 212 }
 213
 214 /**
 215  * Sniff browser language to set the locale automatically.
 216  * Note that is may not work on your server if the corresponding locale is not installed.
 217  *
 218  * @param string $headerLocale Locale send in HTTP headers (e.g. "fr,fr-fr;q=0.8,en;q=0.5,en-us;q=0.3").
 219  **/
 220 function autoLocale($headerLocale)
 221 {
 222     // Default if browser does not send HTTP_ACCEPT_LANGUAGE
 223     $locales = array('en_US', 'en_US.utf8', 'en_US.UTF-8');
 224     if (! empty($headerLocale)) {
 225         if (preg_match_all('/([a-z]{2,3})[-_]?([a-z]{2})?,?/i', $headerLocale, $matches, PREG_SET_ORDER)) {
 226             $attempts = [];
 227             foreach ($matches as $match) {
 228                 $first = [strtolower($match[1]), strtoupper($match[1])];
 229                 $separators = ['_', '-'];
 230                 $encodings = ['utf8', 'UTF-8'];
 231                 if (!empty($match[2])) {
 232                     $second = [strtoupper($match[2]), strtolower($match[2])];
 233                     $items = [$first, $separators, $second, ['.'], $encodings];
 234                 } else {
 235                     $items = [$first, $separators, $first, ['.'], $encodings];
 236                 }
 237                 $attempts = array_merge($attempts, iterator_to_array(cartesian_product_generator($items)));
 238             }
 239
 240             if (! empty($attempts)) {
 241                 $locales = array_merge(array_map('implode', $attempts), $locales);
 242             }
 243         }
 244     }
 245
 246     setlocale(LC_ALL, $locales);
 247 }
 248
 249 /**
 250  * Build a Generator object representing the cartesian product from given $items.
 251  *
 252  * Example:
 253  *   [['a'], ['b', 'c']]
 254  * will generate:
 255  *   [
 256  *      ['a', 'b'],
 257  *      ['a', 'c'],
 258  *   ]
 259  *
 260  * @param array $items array of array of string
 261  *
 262  * @return Generator representing the cartesian product of given array.
 263  *
 264  * @see https://en.wikipedia.org/wiki/Cartesian_product
 265  */
 266 function cartesian_product_generator($items)
 267 {
 268     if (empty($items)) {
 269         yield [];
 270     }
 271     $subArray = array_pop($items);
 272     if (empty($subArray)) {
 273         return;
 274     }
 275     foreach (cartesian_product_generator($items) as $item) {
 276         foreach ($subArray as $value) {
 277             yield $item + [count($item) => $value];
 278         }
 279     }
 280 }
 281
 282 /**
 283  * Generates a default API secret.
 284  *
 285  * Note that the random-ish methods used in this function are predictable,
 286  * which makes them NOT suitable for crypto.
 287  * BUT the random string is salted with the salt and hashed with the username.
 288  * It makes the generated API secret secured enough for Shaarli.
 289  *
 290  * PHP 7 provides random_int(), designed for cryptography.
 291  * More info: http://stackoverflow.com/questions/4356289/php-random-string-generator
 292
 293  * @param string $username Shaarli login username
 294  * @param string $salt     Shaarli password hash salt
 295  *
 296  * @return string|bool Generated API secret, 12 char length.
 297  *                     Or false if invalid parameters are provided (which will make the API unusable).
 298  */
 299 function generate_api_secret($username, $salt)
 300 {
 301     if (empty($username) || empty($salt)) {
 302         return false;
 303     }
 304
 305     return str_shuffle(substr(hash_hmac('sha512', uniqid($salt), $username), 10, 12));
 306 }
 307
 308 /**
 309  * Trim string, replace sequences of whitespaces by a single space.
 310  * PHP equivalent to `normalize-space` XSLT function.
 311  *
 312  * @param string $string Input string.
 313  *
 314  * @return mixed Normalized string.
 315  */
 316 function normalize_spaces($string)
 317 {
 318     return preg_replace('/\s{2,}/', ' ', trim($string));
 319 }
 320
 321 /**
 322  * Format the date according to the locale.
 323  *
 324  * Requires php-intl to display international datetimes,
 325  * otherwise default format '%c' will be returned.
 326  *
 327  * @param DateTime $date to format.
 328  * @param bool     $time Displays time if true.
 329  * @param bool     $intl Use international format if true.
 330  *
 331  * @return bool|string Formatted date, or false if the input is invalid.
 332  */
 333 function format_date($date, $time = true, $intl = true)
 334 {
 335     if (! $date instanceof DateTime) {
 336         return false;
 337     }
 338
 339     if (! $intl || ! class_exists('IntlDateFormatter')) {
 340         $format = $time ? '%c' : '%x';
 341         return strftime($format, $date->getTimestamp());
 342     }
 343
 344     $formatter = new IntlDateFormatter(
 345         setlocale(LC_TIME, 0),
 346         IntlDateFormatter::LONG,
 347         $time ? IntlDateFormatter::LONG : IntlDateFormatter::NONE
 348     );
 349
 350     return $formatter->format($date);
 351 }
 352
 353 /**
 354  * Check if the input is an integer, no matter its real type.
 355  *
 356  * PHP is a bit messy regarding this:
 357  *   - is_int returns false if the input is a string
 358  *   - ctype_digit returns false if the input is an integer or negative
 359  *
 360  * @param mixed $input value
 361  *
 362  * @return bool true if the input is an integer, false otherwise
 363  */
 364 function is_integer_mixed($input)
 365 {
 366     if (is_array($input) || is_bool($input) || is_object($input)) {
 367         return false;
 368     }
 369     $input = strval($input);
 370     return ctype_digit($input) || (startsWith($input, '-') && ctype_digit(substr($input, 1)));
 371 }
 372
 373 /**
 374  * Convert post_max_size/upload_max_filesize (e.g. '16M') parameters to bytes.
 375  *
 376  * @param string $val Size expressed in string.
 377  *
 378  * @return int Size expressed in bytes.
 379  */
 380 function return_bytes($val)
 381 {
 382     if (is_integer_mixed($val) || $val === '0' || empty($val)) {
 383         return $val;
 384     }
 385     $val = trim($val);
 386     $last = strtolower($val[strlen($val)-1]);
 387     $val = intval(substr($val, 0, -1));
 388     switch($last) {
 389         case 'g': $val *= 1024;
 390         case 'm': $val *= 1024;
 391         case 'k': $val *= 1024;
 392     }
 393     return $val;
 394 }
 395
 396 /**
 397  * Return a human readable size from bytes.
 398  *
 399  * @param int $bytes value
 400  *
 401  * @return string Human readable size
 402  */
 403 function human_bytes($bytes)
 404 {
 405     if ($bytes === '') {
 406         return t('Setting not set');
 407     }
 408     if (! is_integer_mixed($bytes)) {
 409         return $bytes;
 410     }
 411     $bytes = intval($bytes);
 412     if ($bytes === 0) {
 413         return t('Unlimited');
 414     }
 415
 416     $units = [t('B'), t('kiB'), t('MiB'), t('GiB')];
 417     for ($i = 0; $i < count($units) && $bytes >= 1024; ++$i) {
 418         $bytes /= 1024;
 419     }
 420
 421     return round($bytes) . $units[$i];
 422 }
 423
 424 /**
 425  * Try to determine max file size for uploads (POST).
 426  * Returns an integer (in bytes) or formatted depending on $format.
 427  *
 428  * @param mixed $limitPost   post_max_size PHP setting
 429  * @param mixed $limitUpload upload_max_filesize PHP setting
 430  * @param bool  $format      Format max upload size to human readable size
 431  *
 432  * @return int|string max upload file size
 433  */
 434 function get_max_upload_size($limitPost, $limitUpload, $format = true)
 435 {
 436     $size1 = return_bytes($limitPost);
 437     $size2 = return_bytes($limitUpload);
 438     // Return the smaller of two:
 439     $maxsize = min($size1, $size2);
 440     return $format ? human_bytes($maxsize) : $maxsize;
 441 }
 442
 443 /**
 444  * Sort the given array alphabetically using php-intl if available.
 445  * Case sensitive.
 446  *
 447  * Note: doesn't support multidimensional arrays
 448  *
 449  * @param array $data    Input array, passed by reference
 450  * @param bool  $reverse Reverse sort if set to true
 451  * @param bool  $byKeys  Sort the array by keys if set to true, by value otherwise.
 452  */
 453 function alphabetical_sort(&$data, $reverse = false, $byKeys = false)
 454 {
 455     $callback = function($a, $b) use ($reverse) {
 456         // Collator is part of PHP intl.
 457         if (class_exists('Collator')) {
 458             $collator = new Collator(setlocale(LC_COLLATE, 0));
 459             if (!intl_is_failure(intl_get_error_code())) {
 460                 return $collator->compare($a, $b) * ($reverse ? -1 : 1);
 461             }
 462         }
 463
 464         return strcasecmp($a, $b) * ($reverse ? -1 : 1);
 465     };
 466
 467     if ($byKeys) {
 468         uksort($data, $callback);
 469     } else {
 470         usort($data, $callback);
 471     }
 472 }