/**
* checks if a Social Security Number is valid
* needs the first three digits and first two digits and the
* final four digits as separate integer parameters
* @param int $area 3-digit group in a SSN
* @param int $group 2-digit group in a SSN
* @param int $serial 4-digit group in a SSN
* @param array $high_groups array of highest issued group numbers
* area number=>group number
*/
function ssnCheck($ssnCheck, $group, $serial, &$high_groups)
{
if (is_array($ssnCheck)) {
extract($ssnCheck);
}
// perform trivial checks
// no field should contain all zeros
if (!($area && $group && $serial)) {
return false;
}
// check if this area has been assigned yet
if (!($high_group = $high_groups[$area])) {
return false;
}
$high_group_range = Validate_US::ssnGroupRange($high_group);
$group_range = Validate_US::ssnGroupRange($group);
// if the assigned range is higher than this group number, we're OK
if ($high_group_range > $group_range) {
return true;
} else {
// if the assigned range is lower than the group number, that's bad
if ($high_group_range < $group_range) {
return false;
} else {
// we must be in the same range, check the actual numbers
if ($high_group >= $group) {
return true;
} else {
return false;
}
}
}
}
