Auth Data from DB');
if ($ad == null) {
echo 'Invalid Yubikey '.$devId;
exit;
} else {
debug($ad);
}
$k = b64ToModhex($ad['secret']);
//debug('aes key in modhex = '.$k);
$key16 = ModHex::Decode($k);
//debug('aes key in hex = ['.$key16.'], length = '.strlen($key16));
//// Decode OTP from input
//
debug('From OTP decoded
');
$decoded_token = Yubikey::Decode($otp, $key16);
debug($decoded_token);
if ( ! is_array($decoded_token) ) {
die ('DECODING FAILED: '.$decoded_token."\n");
}
//// Sanity check key status
//
if ($ad['active'] < 1) {
die ('The Yubikey is not activated!');
}
// Sanity check client status
//
if ($ad['c_active'] < 1) {
die ('The Client is not activated!');
}
// Sanity check token ID
//
if (strlen($decoded_token["public_id"]) == 12 ) {
debug("Token ID OK (".$decoded_token["public_id"].")");
} else { die("TOKEN ID FAILED, ".$decoded_token["public_id"]); }
// Sanity check the OTP
//
if ( strlen($decoded_token["token"]) != 32) {
die("Wrong OTP length,".strlen($decoded_token["token"]));
}
// Check the session counter
//
$sessionCounter = $decoded_token["session_counter"]; // From the req
$seenSessionCounter = $ad['counter']; // From DB
$scDiff = $seenSessionCounter - $sessionCounter;
if ($scDiff > 0) {
die("Replayed session counter=".$sessionCounter.', seen='.$seenSessionCounter);
} else {
debug("Session counter OK (".$sessionCounter.")");
}
$hi = $decoded_token["high"]; // From the req
$seenHi = $ad['high']; // From DB
$hiDiff = $seenHi - $hi;
if ($scDiff == 0 && $hiDiff > 0) {
die("Replayed high counter=".$hi.', seen='.$seenHi);
} else {
debug("High counter OK (".$hi.")");
}
$lo = $decoded_token["low"]; // From the req
$seenLo = $ad['low']; // From DB
$loDiff = $seenLo - $lo;
if ($scDiff == 0 && $hiDiff == 0 && $loDiff >= 0) {
die("Replayed low counter=".$lo.', seen='.$seenLo);
} else {
debug("Low counter OK (".$lo.")");
}
echo 'Validation OK for Yubikey: '.$decoded_token["public_id"];
if (updDB($ad['id'], $decoded_token)) {
debug('Validation database updated');
}
function debug($msg, $exit=false) {
global $trace;
if ($trace) {
if (is_array($msg)) {
echo '';
print_r($msg);
echo '
';
} else {
echo $msg;
}
echo "\n";
}
if ($exit) {
die ('Exit
');
}
}
function updDB($id, $new) {
$stmt = 'UPDATE yubikeys SET '.
'accessed=NOW(),'.
'counter='.$new['session_counter'].','.
'low='.$new['low'].','.
'high='.$new['high'].
' WHERE id='.$id;
if (!query($stmt)) {
$err = 'Failed to update validation data of key: '.$id.' by '.$stmt;
debug($err);
writeLog($err);
return false;
}
return true;
}
?>