private function extractWordsFromHeaders(ISblamPost $p)
{
$words = array();
$headers = $p->getHeaders();
foreach ($headers as $name => $val) {
if (!preg_match('/^HTTP_(?!REFERER|HOST|ORIGIN|CACHE|CONNECTION|X_FORWARD|X_REAL|X_CLIENT|CONTENT|PRAGMA|ACCEPT)/', $name)) {
continue;
}
$words[] = "{$name}: {$val}";
}
$ua = isset($headers['HTTP_USER_AGENT']) ? preg_replace('/(\\d)[.\\d]+/', '\\1', $headers['HTTP_USER_AGENT']) : 'no-ua';
$words[] = $ua;
$words[] = $ua . (isset($headers['HTTP_ACCEPT']) ? $headers['HTTP_ACCEPT'] : 'no-a');
$words[] = $ua . (isset($headers['HTTP_ACCEPT_LANGUAGE']) ? $headers['HTTP_ACCEPT_LANGUAGE'] : 'no-al');
$words[] = $ua . (isset($headers['HTTP_ACCEPT_ENCODING']) ? $headers['HTTP_ACCEPT_ENCODING'] : 'no-ae');
$words[] = $ua . (isset($headers['HTTP_ACCEPT_CHARSET']) ? $headers['HTTP_ACCEPT_CHARSET'] : 'no-ac');
$words[] = $ua . (isset($headers['HTTP_TE']) ? $headers['HTTP_TE'] : 'no-te') . (isset($headers['HTTP_PRAGMA']) ? $headers['HTTP_PRAGMA'] : 'no-p') . (isset($headers['HTTP_CACHE_CONTROL']) ? $headers['HTTP_CACHE_CONTROL'] : 'no-cc');
$words[] = $ua . (isset($headers['HTTP_CONNECTION']) ? $headers['HTTP_CONNECTION'] : 'no-c') . (isset($headers['HTTP_EXPECT']) ? $headers['HTTP_EXPECT'] : 'no-e') . (isset($headers['HTTP_VIA']) ? $headers['HTTP_VIA'] : 'no-v');
return $words;
}
function testPost(ISblamPost $p)
{
$h = $p->getHeaders();
if (!$h || count($h) < 2) {
return NULL;
}
// HTTP_HOST is hardcoded! :///
$out = array();
if (!empty($h['HTTP_MOD_SECURITY_MESSAGE'])) {
$out[] = array(1, self::CERTAINITY_HIGH, "mod_security warning");
}
// Buggy .Net always adds header which is only needed for large forms (and browsers tend not to use it)
if (!empty($h["HTTP_EXPECT"]) && false !== strpos($h['HTTP_EXPECT'], '100-') && strlen($p->getRawContent()) < 5000) {
$out[] = array(0.3, self::CERTAINITY_NORMAL, "100-expect .Net header");
}
// Bots tend to send these
if (!empty($h["HTTP_PRAGMA"])) {
$out[] = array(empty($h["HTTP_VIA"]) ? 0.3 : 0.1, self::CERTAINITY_LOW, "Pragma header");
}
if (!empty($h["HTTP_RANGE"])) {
$out[] = array(0.5, self::CERTAINITY_HIGH, "Range header");
}
if (!empty($h["HTTP_PROXY_CONNECTION"])) {
$out[] = array(0.2, self::CERTAINITY_LOW, "Proxy-Connection header");
}
if (!empty($h["HTTP_REFERER"]) && ($cnt = substr_count($h["HTTP_REFERER"], "http://")) > 1) {
$out[] = array(min(1.5, 0.5 + $cnt / 6), self::CERTAINITY_HIGH, "Multiple links in referrer");
}
if (($cnt = count($p->getAuthorIPs())) > 4) {
$out[] = array(($cnt - 2) / 10, $cnt > 7 ? self::CERTAINITY_HIGH : self::CERTAINITY_NORMAL, "Insane number of relays ({$cnt})");
}
// Unpatched IE!?
if (!empty($h["HTTP_USER_AGENT"]) && preg_match('/MSIE [456]\\.[0-9]; Windows (?:9|NT 5)/', $h['HTTP_USER_AGENT'])) {
$out[] = array(0.3, self::CERTAINITY_NORMAL, "Unpatched IE");
}
// Browsers almost always send these
if (empty($h["HTTP_ACCEPT"])) {
$out[] = array(0.7, self::CERTAINITY_NORMAL, "Missing Accept header");
}
if (empty($h["HTTP_USER_AGENT"])) {
$out[] = array(1, self::CERTAINITY_NORMAL, "Missing UA header");
}
if (empty($h["HTTP_ACCEPT_LANGUAGE"])) {
$out[] = array(0.5, self::CERTAINITY_NORMAL, "Missing Accept-Language header");
}
if (empty($h["HTTP_ACCEPT_ENCODING"]) && empty($h["HTTP_VIA"]) && (empty($h["HTTP_USER_AGENT"]) || false === strpos($h["HTTP_USER_AGENT"], 'Mozilla/4.0 (compatible; MSIE '))) {
$out[] = array(0.4, self::CERTAINITY_LOW, "Missing Accept-Encoding header");
}
if (!empty($h["HTTP_ACCEPT_CHARSET"])) {
$out[] = array(-0.2, self::CERTAINITY_LOW, "Has Accept-Charset header");
}
// Non-transparent proxy must add Via header
if (empty($h["HTTP_VIA"]) && (!empty($h['HTTP_X_FORWARDED_FOR']) || !empty($h['HTTP_MAX_FORWARDS']))) {
$out[] = array(0.2, self::CERTAINITY_LOW, "Lame proxy");
}
// TE: requires Connection:TE
if (!empty($h["HTTP_TE"]) && (empty($h['HTTP_CONNECTION']) || !preg_match('!\\bTE\\b!', $h['HTTP_CONNECTION']))) {
$out[] = array(0.2, self::CERTAINITY_NORMAL, "Invalid TE header");
}
// Googlebot doesn't post comments!
if (!empty($h['HTTP_USER_AGENT']) && preg_match('!Googlebot[/ -]|Slurp|Wget/|W3C_Validator|Advertise\\.com|nicebot|MMCrawler/|MSIECrawler|ia_archiver|WebaltBot/|nutbot\\.com|\\+http://search\\.!', $h['HTTP_USER_AGENT'])) {
$out[] = array(1, self::CERTAINITY_NORMAL, "Bots don't post comments");
}
// Headless browsers no thanks
if (!empty($h['HTTP_USER_AGENT']) && preg_match('!PhantomJS|CasperJS!', $h['HTTP_USER_AGENT'])) {
$out[] = array(1, self::CERTAINITY_HIGH, "Nice try, PhantomJS");
}
if (!empty($h['HTTP_USERAGENT']) || !empty($h['HTTP_USER_AGENT']) && preg_match('!^User-Agent!i', $h['HTTP_USER_AGENT'])) {
$out[] = array(1, self::CERTAINITY_NORMAL, "Really badly written bot");
}
// I assume multipart forms are too tricky for most bots
if (!empty($h['HTTP_CONTENT_LENGTH']) && !empty($h['HTTP_CONTENT_TYPE']) && preg_match('!^\\s*multipart/form-data\\s*;\\s*boundary\\s*=!i', $h['HTTP_CONTENT_TYPE'])) {
$out[] = array(-0.2, self::CERTAINITY_LOW, "Multipart form");
}
// browsers nicely decode and normalize paths, remove fragment part
if (($path = $p->getPath()) && preg_match('!&|^https?://|^//|/%7e|#|\\.\\./!i', $path)) {
$out[] = array(0.3, self::CERTAINITY_NORMAL, "Improperly encoded path");
}
if (!empty($h["HTTP_REFERER"]) && preg_match('!&|/%7e|\\.\\./!i', $h["HTTP_REFERER"])) {
$out[] = array(0.25, self::CERTAINITY_LOW, "Improperly encoded referer");
}
if (count($out)) {
return $out;
}
}
