spam.php

   1 <?php
   2 // $Id: spam.php,v 1.11 2006/11/03 15:58:00 henoheno Exp $
   3 // Copyright (C) 2006 PukiWiki Developers Team
   4 // License: GPL v2 or (at your option) any later version
   5
   6 // Functions for Concept-work of spam-uri metrics
   7
   8 // Return an array of normalized/parsed URIs in the $string
   9 // [OK] http://nasty.example.org#nasty_string
  10 // [OK] http://nasty.example.org/foo/xxx#nasty_string/bar
  11 // [OK] ftp://dfshodfs:80/dfsdfs
  12 // [OK] http://victim.example.org/go?http%3A%2F%2Fnasty.example.org
  13 // [OK] http://victim.example.org/gphttp://nasty.example.org
  14 function spam_pickup($string = '')
  15 {
  16         // Preprocess: urldecode() and adding space(s)
  17         $string = preg_replace(
  18                 array(
  19                         '#(?:https?|ftp):/#',
  20                         '#\b[a-z][a-z0-9.+-]{1,8}://#i',
  21                         '#[a-z][a-z0-9.+-]{1,8}://#i'
  22                 ), ' $0', urldecode($string));
  23
  24         // URI pickup: Not available for user@password, IDN, Fragment(=ignored)
  25         $array = array();
  26         preg_match_all(
  27                 // Refer RFC3986
  28                 '#(\b[a-z][a-z0-9.+-]{1,8})://' .       // 1: Scheme
  29                 '(' .
  30                         // 2: Host
  31                         '\[[0-9a-f:.]+\]' . '|' .                               // IPv6([colon-hex and dot]): RFC2732
  32                         '(?:[0-9]{1-3}\.){3}[0-9]{1-3}' . '|' . // IPv4(dot-decimal): 001.22.3.44
  33                         '[^\s<>"\'\[\]:/\#?]+' .                                // FQDN: foo.example.org
  34                 ')' .
  35                 '(?::([a-z0-9]{2,}))?' .                        // 3: Port
  36                 '((?:/+[^\s<>"\'\[\]/\#]+)*/+)?' .      // 4: Directory path or path-info
  37                 '([^\s<>"\'\[\]\#]+)?' .                        // 5: File and query string
  38                                                                                         // #: Fragment(ignored)
  39                 '#i',
  40                  $string, $array, PREG_SET_ORDER | PREG_OFFSET_CAPTURE);
  41         //var_dump(recursive_map('htmlspecialchars', $array));
  42         // Shrink $array
  43         $parts = array(1 => 'scheme', 2 => 'host', 3 => 'port',
  44                 4 => 'path', 5 => 'file');
  45         $default = array('');
  46         foreach(array_keys($array) as $uri) {
  47                 unset($array[$uri][0]); // Matched string itself
  48                 array_rename_keys($array[$uri], $parts, TRUE, $default);
  49                 $offset = $array[$uri]['scheme'][1]; // Scheme's offset
  50
  51                 // Remove offsets (with normalization)
  52                 foreach(array_keys($array[$uri]) as $part) {
  53                         $array[$uri][$part] =
  54                                         strtolower($array[$uri][$part][0]);
  55                 }
  56                 $array[$uri]['path']   = path_normalize($array[$uri]['path']);
  57                 $array[$uri]['offset'] = $offset;
  58                 $array[$uri]['area']   = 0;
  59         }
  60
  61         // Area elevation for '(especially external)link' intension
  62         if (! empty($array)) {
  63                 // Anchor tags by preg_match_all()
  64                 // [OK] <a href="http://nasty.example.com">visit http://nasty.example.com/</a>
  65                 // [NG] <a href="http://ng.example.com">visit http://ng.example.com _not_ended_
  66                 // [NG] <a href=  >Good site!</a> <a href= "#" >test</a>
  67                 $areas = array();
  68                 preg_match_all('#<a\b[^>]*href[^>]*>.*?</a\b[^>]*(>)#i',
  69                          $string, $areas, PREG_SET_ORDER | PREG_OFFSET_CAPTURE);
  70                 //var_dump(recursive_map('htmlspecialchars', $areas));
  71                 foreach(array_keys($areas) as $area) {
  72                         $areas[$area] =  array(
  73                                 $areas[$area][0][1], // [0][1] = Area start (<a href>)
  74                                 $areas[$area][1][1], // [1][1] = Area end   (</a>)
  75                         );
  76                 }
  77                 area_measure($areas, $array);
  78
  79                 // Various Wiki syntax
  80                 // [text_or_uri>text_or_uri]
  81                 // [text_or_uri:text_or_uri]
  82                 // [text_or_uri|text_or_uri]
  83                 // [text_or_uri->text_or_uri]
  84                 // [text_or_uri text_or_uri] // MediaWiki
  85                 // MediaWiki: [http://nasty.example.com/ visit http://nasty.example.com/]
  86
  87                 // phpBB's "BBCode" by preg_match_all()
  88                 // [url]http://nasty.example.com/[/url]
  89                 // [link]http://nasty.example.com/[/link]
  90                 // [url=http://nasty.example.com]visit http://nasty.example.com/[/url]
  91                 // [link http://nasty.example.com/]buy something[/link]
  92                 // ?? [url=][/url]
  93                 $areas = array();
  94                 preg_match_all('#\[(url|link)\b[^\]]*\].*?\[/\1\b[^\]]*(\])#i',
  95                          $string, $areas, PREG_SET_ORDER | PREG_OFFSET_CAPTURE);
  96                 //var_dump(recursive_map('htmlspecialchars', $areas));
  97                 foreach(array_keys($areas) as $area) {
  98                         $areas[$area] = array(
  99                                 $areas[$area][0][1], // [0][1] = Area start ([url])
 100                                 $areas[$area][2][1], // [4][1] = Area end   ([/url])
 101                         );
 102                 }
 103                 area_measure($areas, $array);
 104
 105                 // Remove 'offset's for area_measure()
 106                 foreach(array_keys($array) as $key)
 107                         unset($array[$key]['offset']);
 108         }
 109
 110         return $array;
 111 }
 112
 113 // $array[0] => $array['name']
 114 function array_rename_keys(& $array, $rename = array(), $force = FALSE, $default = '')
 115 {
 116     if ($force) {
 117                 foreach($rename as $from => $to) {
 118                         if (isset($array[$from])) {
 119                                 $array[$to] = & $array[$from];
 120                                 unset($array[$from]);
 121                         } else  {
 122                                 $array[$to] = $default;
 123                         }
 124                 }
 125         } else {
 126                 foreach(array_keys($rename) as $from) {
 127                         if (! isset($array[$from])) {
 128                                 return FALSE;
 129                         }
 130                 }
 131                 foreach($rename as $from => $to) {
 132                         $array[$to] = & $array[$from];
 133                         unset($array[$from]);
 134                 }
 135         }
 136         return TRUE;
 137 }
 138
 139
 140 // Path normalization
 141 // example.org => example.org/
 142 // example.org#hoge -> example.org/#hoge
 143 // example.org/path/a/b/./c////./d -> example.org/path/a/b/c/d
 144 // example.org/path/../../a/../back
 145 function path_normalize($path = '', $divider = '/', $addroot = TRUE)
 146 {
 147         if (! is_string($path) || $path == '') {
 148                 $path = $addroot ? $divider : '';
 149         } else {
 150                 $path = trim($path);
 151                 $last = ($path[strlen($path) - 1] == $divider) ? $divider : '';
 152                 $array = explode($divider, $path);
 153
 154                 // Remove paddings
 155                 foreach(array_keys($array) as $key) {
 156                         if ($array[$key] == '' || $array[$key] == '.')
 157                                  unset($array[$key]);
 158                 }
 159                 // Back-track
 160                 $tmp = array();
 161                 foreach($array as $value) {
 162                         if ($value == '..') {
 163                                 array_pop($tmp);
 164                         } else {
 165                                 array_push($tmp, $value);
 166                         }
 167                 }
 168                 $array = & $tmp;
 169
 170                 $path = $addroot ? $divider : '';
 171                 if (! empty($array)) $path .= implode($divider, $array) . $last;
 172         }
 173
 174         return $path;
 175 }
 176
 177 // If in doubt, it's a little doubtful
 178 function area_measure($areas, &$array, $belief = -1, $a_key = 'area', $o_key = 'offset')
 179 {
 180         if (! is_array($areas) || ! is_array($array)) return;
 181
 182         $areas_keys = array_keys($areas);
 183         foreach(array_keys($array) as $u_index) {
 184                 $offset = isset($array[$u_index][$o_key]) ?
 185                         intval($array[$u_index][$o_key]) : 0;
 186                 foreach($areas_keys as $a_index) {
 187                         if (isset($array[$u_index][$a_key])) {
 188                                 $offset_s = intval($areas[$a_index][0]);
 189                                 $offset_e = intval($areas[$a_index][1]);
 190                                 // [Area => inside <= Area]
 191                                 if ($offset_s < $offset && $offset < $offset_e) {
 192                                         $array[$u_index][$a_key] += $belief;
 193                                 }
 194                         }
 195                 }
 196         }
 197 }
 198
 199 function is_uri_spam($target = '')
 200 {
 201         $is_spam = FALSE;
 202         $urinum = 0;
 203
 204         if (is_array($target)) {
 205                 foreach($target as $str) {
 206                         list($is_spam, $_urinum) = is_uri_spam($str);
 207                         $urinum += $_urinum;
 208                         if ($is_spam) break;
 209                 }
 210         } else {
 211                 $pickups = spam_pickup($target);
 212                 $urinum += count($pickups);
 213                 if (! empty($pickups)) {
 214                         // Some users want to post one or two URL, but ...
 215                         if ($urinum > 2) {
 216                                 $is_spam = TRUE;        // Too many!
 217                         } else {
 218                                 foreach($pickups as $pickup) {
 219                                         if ($pickup['area'] < 0) {
 220                                                 $is_spam = TRUE;
 221                                                 break;
 222                                         }
 223                                 }
 224                         }
 225                 }
 226         }
 227
 228         return array($is_spam, $urinum);
 229 }
 230
 231
 232 // TODO: tracker\82ª\95Ï\93®\82·\82é\8e\96\82à\82 \82è\81A\82¢\82Á\82»\82Ì\82±\82Æ$post\82â $vars\91S\82Ä\82ð\91Î\8fÛ\82É\82µ\82½\95û\82ª\82¢\82¢\81B
 233 //   \82»\82¤\82·\82ê\82Î\98R\82ê\82à\96³\82¢\81B
 234 //   \82Å\81A\83\81\81[\83\8b\82Í\82Ð\82Á\82©\82¯\82½\83t\83B\81[\83\8b\83h\82¾\82¯\82É\82·\82é\82Æ\82©\81B
 235 //   edit\91Î\8dô\82Æ\82µ\82Ä\82Í\96³\8e\8b\82·\82é\83t\83B\81[\83\8b\83h\82ð\97p\88Ó\82·\82é\82Æ\82©\81B
 236
 237 // Mail to administrator with more measurement data?
 238 // Simple/fast spam filter (for one text field)
 239 function pkwk_spamfilter($action, $page, $target = array('title' => ''))
 240 {
 241         $is_spam = FALSE;
 242         list($is_spam) = is_uri_spam($target);
 243
 244         if ($is_spam) {
 245                 global $notify, $notify_subject;
 246                 if ($notify) {
 247                         $footer['ACTION'] = $action;
 248                         $footer['PAGE']   = '[blocked] ' . $page;
 249                         $footer['URI']    = get_script_uri() . '?' . rawurlencode($page);
 250                         $footer['USER_AGENT']  = TRUE;
 251                         $footer['REMOTE_ADDR'] = TRUE;
 252                         pkwk_mail_notify($notify_subject,  var_export($target, TRUE), $footer);
 253                         unset($footer);
 254                 }
 255         }
 256
 257         if ($is_spam) spam_exit();
 258 }
 259
 260 function spam_exit()
 261 {
 262         die("\n");
 263 }
 264
 265 ?>