TYPO3 Core

Hi all,

as noted by several other people, the t3lib_div::validEmail() method is quite... "simplistic" at the moment - lets put it that way ;-)
I suggest to incorporate the following code developed in an article in the June 2007 Issue of Linux Journal by Douglas Lovell.

/**
SOURCE: http://www.linuxjournal.com/article/9585

Validate an email address.
Provide email address (raw input)
Returns true if the email address has the email
address format and the domain exists.
*/

function validEmail($email) {
$isValid = true;
$atIndex = strrpos($email, "@");
if (is_bool($atIndex) && !$atIndex) {
$isValid = false;
} else {
$domain = substr($email, $atIndex+1);
$local = substr($email, 0, $atIndex);
$localLen = strlen($local);
$domainLen = strlen($domain);
if ($localLen < 1 || $localLen > 64) {
// local part length exceeded
$isValid = false;
} else if ($domainLen < 1 || $domainLen > 255) {
// domain part length exceeded
$isValid = false;
} else if ($local⁰ '.' || $local[$localLen-1] '.') {
// local part starts or ends with '.'
$isValid = false;
} else if (preg_match('/\\.\\./', $local)) {
// local part has two consecutive dots
$isValid = false;
} else if (!preg_match('/^[A-Za-z0-9\\-\\.]+$/', $domain)) {
// character not valid in domain part
$isValid = false;
} else if (preg_match('/\\.\\./', $domain)) {
//domain part has two consecutive dots
$isValid = false;
} else if (!preg_match('/^(\\\\.|[A-Za-z0-9!#%&`_=\\/$\'*+?^{}|~.-])+$/', str_replace("\\\\","",$local))) {
// character not valid in local part unless
// local part is quoted
if (!preg_match('/^"(\\\\"|[^"])+"$/', str_replace("\\\\","", $local))) {
$isValid = false;
}
}
if ($isValid && !(checkdnsrr($domain,"MX") || checkdnsrr($domain,"A"))) {
// domain not found in DNS
$isValid = false;
}
}
return $isValid;
}
(issue imported from #M5688)