nextcloud/3dparty/Mail/RFC822.php

924 lines
31 KiB
PHP

<?php
// +-----------------------------------------------------------------------+
// | Copyright (c) 2001-2002, Richard Heyes |
// | All rights reserved. |
// | |
// | Redistribution and use in source and binary forms, with or without |
// | modification, are permitted provided that the following conditions |
// | are met: |
// | |
// | o Redistributions of source code must retain the above copyright |
// | notice, this list of conditions and the following disclaimer. |
// | o Redistributions in binary form must reproduce the above copyright |
// | notice, this list of conditions and the following disclaimer in the |
// | documentation and/or other materials provided with the distribution.|
// | o The names of the authors may not be used to endorse or promote |
// | products derived from this software without specific prior written |
// | permission. |
// | |
// | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
// | "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
// | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
// | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
// | OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
// | SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
// | LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
// | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
// | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
// | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
// | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
// | |
// +-----------------------------------------------------------------------+
// | Authors: Richard Heyes <richard@phpguru.org> |
// | Chuck Hagenbuch <chuck@horde.org> |
// +-----------------------------------------------------------------------+
/**
* RFC 822 Email address list validation Utility
*
* What is it?
*
* This class will take an address string, and parse it into it's consituent
* parts, be that either addresses, groups, or combinations. Nested groups
* are not supported. The structure it returns is pretty straight forward,
* and is similar to that provided by the imap_rfc822_parse_adrlist(). Use
* print_r() to view the structure.
*
* How do I use it?
*
* $address_string = 'My Group: "Richard" <richard@localhost> (A comment), ted@example.com (Ted Bloggs), Barney;';
* $structure = Mail_RFC822::parseAddressList($address_string, 'example.com', true)
* print_r($structure);
*
* @author Richard Heyes <richard@phpguru.org>
* @author Chuck Hagenbuch <chuck@horde.org>
* @version $Revision: 1.21 $
* @license BSD
* @package Mail
*/
class Mail_RFC822 {
/**
* The address being parsed by the RFC822 object.
* @var string $address
*/
var $address = '';
/**
* The default domain to use for unqualified addresses.
* @var string $default_domain
*/
var $default_domain = 'localhost';
/**
* Should we return a nested array showing groups, or flatten everything?
* @var boolean $nestGroups
*/
var $nestGroups = true;
/**
* Whether or not to validate atoms for non-ascii characters.
* @var boolean $validate
*/
var $validate = true;
/**
* The array of raw addresses built up as we parse.
* @var array $addresses
*/
var $addresses = array();
/**
* The final array of parsed address information that we build up.
* @var array $structure
*/
var $structure = array();
/**
* The current error message, if any.
* @var string $error
*/
var $error = null;
/**
* An internal counter/pointer.
* @var integer $index
*/
var $index = null;
/**
* The number of groups that have been found in the address list.
* @var integer $num_groups
* @access public
*/
var $num_groups = 0;
/**
* A variable so that we can tell whether or not we're inside a
* Mail_RFC822 object.
* @var boolean $mailRFC822
*/
var $mailRFC822 = true;
/**
* A limit after which processing stops
* @var int $limit
*/
var $limit = null;
/**
* Sets up the object. The address must either be set here or when
* calling parseAddressList(). One or the other.
*
* @access public
* @param string $address The address(es) to validate.
* @param string $default_domain Default domain/host etc. If not supplied, will be set to localhost.
* @param boolean $nest_groups Whether to return the structure with groups nested for easier viewing.
* @param boolean $validate Whether to validate atoms. Turn this off if you need to run addresses through before encoding the personal names, for instance.
*
* @return object Mail_RFC822 A new Mail_RFC822 object.
*/
function Mail_RFC822($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
{
if (isset($address)) $this->address = $address;
if (isset($default_domain)) $this->default_domain = $default_domain;
if (isset($nest_groups)) $this->nestGroups = $nest_groups;
if (isset($validate)) $this->validate = $validate;
if (isset($limit)) $this->limit = $limit;
}
/**
* Starts the whole process. The address must either be set here
* or when creating the object. One or the other.
*
* @access public
* @param string $address The address(es) to validate.
* @param string $default_domain Default domain/host etc.
* @param boolean $nest_groups Whether to return the structure with groups nested for easier viewing.
* @param boolean $validate Whether to validate atoms. Turn this off if you need to run addresses through before encoding the personal names, for instance.
*
* @return array A structured array of addresses.
*/
function parseAddressList($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
{
if (!isset($this) || !isset($this->mailRFC822)) {
$obj = new Mail_RFC822($address, $default_domain, $nest_groups, $validate, $limit);
return $obj->parseAddressList();
}
if (isset($address)) $this->address = $address;
if (isset($default_domain)) $this->default_domain = $default_domain;
if (isset($nest_groups)) $this->nestGroups = $nest_groups;
if (isset($validate)) $this->validate = $validate;
if (isset($limit)) $this->limit = $limit;
$this->structure = array();
$this->addresses = array();
$this->error = null;
$this->index = null;
// Unfold any long lines in $this->address.
$this->address = preg_replace('/\r?\n/', "\r\n", $this->address);
$this->address = preg_replace('/\r\n(\t| )+/', ' ', $this->address);
while ($this->address = $this->_splitAddresses($this->address));
if ($this->address === false || isset($this->error)) {
require_once 'PEAR.php';
return PEAR::raiseError($this->error);
}
// Validate each address individually. If we encounter an invalid
// address, stop iterating and return an error immediately.
foreach ($this->addresses as $address) {
$valid = $this->_validateAddress($address);
if ($valid === false || isset($this->error)) {
require_once 'PEAR.php';
return PEAR::raiseError($this->error);
}
if (!$this->nestGroups) {
$this->structure = array_merge($this->structure, $valid);
} else {
$this->structure[] = $valid;
}
}
return $this->structure;
}
/**
* Splits an address into separate addresses.
*
* @access private
* @param string $address The addresses to split.
* @return boolean Success or failure.
*/
function _splitAddresses($address)
{
if (!empty($this->limit) && count($this->addresses) == $this->limit) {
return '';
}
if ($this->_isGroup($address) && !isset($this->error)) {
$split_char = ';';
$is_group = true;
} elseif (!isset($this->error)) {
$split_char = ',';
$is_group = false;
} elseif (isset($this->error)) {
return false;
}
// Split the string based on the above ten or so lines.
$parts = explode($split_char, $address);
$string = $this->_splitCheck($parts, $split_char);
// If a group...
if ($is_group) {
// If $string does not contain a colon outside of
// brackets/quotes etc then something's fubar.
// First check there's a colon at all:
if (strpos($string, ':') === false) {
$this->error = 'Invalid address: ' . $string;
return false;
}
// Now check it's outside of brackets/quotes:
if (!$this->_splitCheck(explode(':', $string), ':')) {
return false;
}
// We must have a group at this point, so increase the counter:
$this->num_groups++;
}
// $string now contains the first full address/group.
// Add to the addresses array.
$this->addresses[] = array(
'address' => trim($string),
'group' => $is_group
);
// Remove the now stored address from the initial line, the +1
// is to account for the explode character.
$address = trim(substr($address, strlen($string) + 1));
// If the next char is a comma and this was a group, then
// there are more addresses, otherwise, if there are any more
// chars, then there is another address.
if ($is_group && substr($address, 0, 1) == ','){
$address = trim(substr($address, 1));
return $address;
} elseif (strlen($address) > 0) {
return $address;
} else {
return '';
}
// If you got here then something's off
return false;
}
/**
* Checks for a group at the start of the string.
*
* @access private
* @param string $address The address to check.
* @return boolean Whether or not there is a group at the start of the string.
*/
function _isGroup($address)
{
// First comma not in quotes, angles or escaped:
$parts = explode(',', $address);
$string = $this->_splitCheck($parts, ',');
// Now we have the first address, we can reliably check for a
// group by searching for a colon that's not escaped or in
// quotes or angle brackets.
if (count($parts = explode(':', $string)) > 1) {
$string2 = $this->_splitCheck($parts, ':');
return ($string2 !== $string);
} else {
return false;
}
}
/**
* A common function that will check an exploded string.
*
* @access private
* @param array $parts The exloded string.
* @param string $char The char that was exploded on.
* @return mixed False if the string contains unclosed quotes/brackets, or the string on success.
*/
function _splitCheck($parts, $char)
{
$string = $parts[0];
for ($i = 0; $i < count($parts); $i++) {
if ($this->_hasUnclosedQuotes($string)
|| $this->_hasUnclosedBrackets($string, '<>')
|| $this->_hasUnclosedBrackets($string, '[]')
|| $this->_hasUnclosedBrackets($string, '()')
|| substr($string, -1) == '\\') {
if (isset($parts[$i + 1])) {
$string = $string . $char . $parts[$i + 1];
} else {
$this->error = 'Invalid address spec. Unclosed bracket or quotes';
return false;
}
} else {
$this->index = $i;
break;
}
}
return $string;
}
/**
* Checks if a string has an unclosed quotes or not.
*
* @access private
* @param string $string The string to check.
* @return boolean True if there are unclosed quotes inside the string, false otherwise.
*/
function _hasUnclosedQuotes($string)
{
$string = explode('"', $string);
$string_cnt = count($string);
for ($i = 0; $i < (count($string) - 1); $i++)
if (substr($string[$i], -1) == '\\')
$string_cnt--;
return ($string_cnt % 2 === 0);
}
/**
* Checks if a string has an unclosed brackets or not. IMPORTANT:
* This function handles both angle brackets and square brackets;
*
* @access private
* @param string $string The string to check.
* @param string $chars The characters to check for.
* @return boolean True if there are unclosed brackets inside the string, false otherwise.
*/
function _hasUnclosedBrackets($string, $chars)
{
$num_angle_start = substr_count($string, $chars[0]);
$num_angle_end = substr_count($string, $chars[1]);
$this->_hasUnclosedBracketsSub($string, $num_angle_start, $chars[0]);
$this->_hasUnclosedBracketsSub($string, $num_angle_end, $chars[1]);
if ($num_angle_start < $num_angle_end) {
$this->error = 'Invalid address spec. Unmatched quote or bracket (' . $chars . ')';
return false;
} else {
return ($num_angle_start > $num_angle_end);
}
}
/**
* Sub function that is used only by hasUnclosedBrackets().
*
* @access private
* @param string $string The string to check.
* @param integer &$num The number of occurences.
* @param string $char The character to count.
* @return integer The number of occurences of $char in $string, adjusted for backslashes.
*/
function _hasUnclosedBracketsSub($string, &$num, $char)
{
$parts = explode($char, $string);
for ($i = 0; $i < count($parts); $i++){
if (substr($parts[$i], -1) == '\\' || $this->_hasUnclosedQuotes($parts[$i]))
$num--;
if (isset($parts[$i + 1]))
$parts[$i + 1] = $parts[$i] . $char . $parts[$i + 1];
}
return $num;
}
/**
* Function to begin checking the address.
*
* @access private
* @param string $address The address to validate.
* @return mixed False on failure, or a structured array of address information on success.
*/
function _validateAddress($address)
{
$is_group = false;
$addresses = array();
if ($address['group']) {
$is_group = true;
// Get the group part of the name
$parts = explode(':', $address['address']);
$groupname = $this->_splitCheck($parts, ':');
$structure = array();
// And validate the group part of the name.
if (!$this->_validatePhrase($groupname)){
$this->error = 'Group name did not validate.';
return false;
} else {
// Don't include groups if we are not nesting
// them. This avoids returning invalid addresses.
if ($this->nestGroups) {
$structure = new stdClass;
$structure->groupname = $groupname;
}
}
$address['address'] = ltrim(substr($address['address'], strlen($groupname . ':')));
}
// If a group then split on comma and put into an array.
// Otherwise, Just put the whole address in an array.
if ($is_group) {
while (strlen($address['address']) > 0) {
$parts = explode(',', $address['address']);
$addresses[] = $this->_splitCheck($parts, ',');
$address['address'] = trim(substr($address['address'], strlen(end($addresses) . ',')));
}
} else {
$addresses[] = $address['address'];
}
// Check that $addresses is set, if address like this:
// Groupname:;
// Then errors were appearing.
if (!count($addresses)){
$this->error = 'Empty group.';
return false;
}
// Trim the whitespace from all of the address strings.
array_map('trim', $addresses);
// Validate each mailbox.
// Format could be one of: name <geezer@domain.com>
// geezer@domain.com
// geezer
// ... or any other format valid by RFC 822.
for ($i = 0; $i < count($addresses); $i++) {
if (!$this->validateMailbox($addresses[$i])) {
if (empty($this->error)) {
$this->error = 'Validation failed for: ' . $addresses[$i];
}
return false;
}
}
// Nested format
if ($this->nestGroups) {
if ($is_group) {
$structure->addresses = $addresses;
} else {
$structure = $addresses[0];
}
// Flat format
} else {
if ($is_group) {
$structure = array_merge($structure, $addresses);
} else {
$structure = $addresses;
}
}
return $structure;
}
/**
* Function to validate a phrase.
*
* @access private
* @param string $phrase The phrase to check.
* @return boolean Success or failure.
*/
function _validatePhrase($phrase)
{
// Splits on one or more Tab or space.
$parts = preg_split('/[ \\x09]+/', $phrase, -1, PREG_SPLIT_NO_EMPTY);
$phrase_parts = array();
while (count($parts) > 0){
$phrase_parts[] = $this->_splitCheck($parts, ' ');
for ($i = 0; $i < $this->index + 1; $i++)
array_shift($parts);
}
foreach ($phrase_parts as $part) {
// If quoted string:
if (substr($part, 0, 1) == '"') {
if (!$this->_validateQuotedString($part)) {
return false;
}
continue;
}
// Otherwise it's an atom:
if (!$this->_validateAtom($part)) return false;
}
return true;
}
/**
* Function to validate an atom which from rfc822 is:
* atom = 1*<any CHAR except specials, SPACE and CTLs>
*
* If validation ($this->validate) has been turned off, then
* validateAtom() doesn't actually check anything. This is so that you
* can split a list of addresses up before encoding personal names
* (umlauts, etc.), for example.
*
* @access private
* @param string $atom The string to check.
* @return boolean Success or failure.
*/
function _validateAtom($atom)
{
if (!$this->validate) {
// Validation has been turned off; assume the atom is okay.
return true;
}
// Check for any char from ASCII 0 - ASCII 127
if (!preg_match('/^[\\x00-\\x7E]+$/i', $atom, $matches)) {
return false;
}
// Check for specials:
if (preg_match('/[][()<>@,;\\:". ]/', $atom)) {
return false;
}
// Check for control characters (ASCII 0-31):
if (preg_match('/[\\x00-\\x1F]+/', $atom)) {
return false;
}
return true;
}
/**
* Function to validate quoted string, which is:
* quoted-string = <"> *(qtext/quoted-pair) <">
*
* @access private
* @param string $qstring The string to check
* @return boolean Success or failure.
*/
function _validateQuotedString($qstring)
{
// Leading and trailing "
$qstring = substr($qstring, 1, -1);
// Perform check, removing quoted characters first.
return !preg_match('/[\x0D\\\\"]/', preg_replace('/\\\\./', '', $qstring));
}
/**
* Function to validate a mailbox, which is:
* mailbox = addr-spec ; simple address
* / phrase route-addr ; name and route-addr
*
* @access public
* @param string &$mailbox The string to check.
* @return boolean Success or failure.
*/
function validateMailbox(&$mailbox)
{
// A couple of defaults.
$phrase = '';
$comment = '';
$comments = array();
// Catch any RFC822 comments and store them separately.
$_mailbox = $mailbox;
while (strlen(trim($_mailbox)) > 0) {
$parts = explode('(', $_mailbox);
$before_comment = $this->_splitCheck($parts, '(');
if ($before_comment != $_mailbox) {
// First char should be a (.
$comment = substr(str_replace($before_comment, '', $_mailbox), 1);
$parts = explode(')', $comment);
$comment = $this->_splitCheck($parts, ')');
$comments[] = $comment;
// +1 is for the trailing )
$_mailbox = substr($_mailbox, strpos($_mailbox, $comment)+strlen($comment)+1);
} else {
break;
}
}
foreach ($comments as $comment) {
$mailbox = str_replace("($comment)", '', $mailbox);
}
$mailbox = trim($mailbox);
// Check for name + route-addr
if (substr($mailbox, -1) == '>' && substr($mailbox, 0, 1) != '<') {
$parts = explode('<', $mailbox);
$name = $this->_splitCheck($parts, '<');
$phrase = trim($name);
$route_addr = trim(substr($mailbox, strlen($name.'<'), -1));
if ($this->_validatePhrase($phrase) === false || ($route_addr = $this->_validateRouteAddr($route_addr)) === false) {
return false;
}
// Only got addr-spec
} else {
// First snip angle brackets if present.
if (substr($mailbox, 0, 1) == '<' && substr($mailbox, -1) == '>') {
$addr_spec = substr($mailbox, 1, -1);
} else {
$addr_spec = $mailbox;
}
if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
return false;
}
}
// Construct the object that will be returned.
$mbox = new stdClass();
// Add the phrase (even if empty) and comments
$mbox->personal = $phrase;
$mbox->comment = isset($comments) ? $comments : array();
if (isset($route_addr)) {
$mbox->mailbox = $route_addr['local_part'];
$mbox->host = $route_addr['domain'];
$route_addr['adl'] !== '' ? $mbox->adl = $route_addr['adl'] : '';
} else {
$mbox->mailbox = $addr_spec['local_part'];
$mbox->host = $addr_spec['domain'];
}
$mailbox = $mbox;
return true;
}
/**
* This function validates a route-addr which is:
* route-addr = "<" [route] addr-spec ">"
*
* Angle brackets have already been removed at the point of
* getting to this function.
*
* @access private
* @param string $route_addr The string to check.
* @return mixed False on failure, or an array containing validated address/route information on success.
*/
function _validateRouteAddr($route_addr)
{
// Check for colon.
if (strpos($route_addr, ':') !== false) {
$parts = explode(':', $route_addr);
$route = $this->_splitCheck($parts, ':');
} else {
$route = $route_addr;
}
// If $route is same as $route_addr then the colon was in
// quotes or brackets or, of course, non existent.
if ($route === $route_addr){
unset($route);
$addr_spec = $route_addr;
if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
return false;
}
} else {
// Validate route part.
if (($route = $this->_validateRoute($route)) === false) {
return false;
}
$addr_spec = substr($route_addr, strlen($route . ':'));
// Validate addr-spec part.
if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
return false;
}
}
if (isset($route)) {
$return['adl'] = $route;
} else {
$return['adl'] = '';
}
$return = array_merge($return, $addr_spec);
return $return;
}
/**
* Function to validate a route, which is:
* route = 1#("@" domain) ":"
*
* @access private
* @param string $route The string to check.
* @return mixed False on failure, or the validated $route on success.
*/
function _validateRoute($route)
{
// Split on comma.
$domains = explode(',', trim($route));
foreach ($domains as $domain) {
$domain = str_replace('@', '', trim($domain));
if (!$this->_validateDomain($domain)) return false;
}
return $route;
}
/**
* Function to validate a domain, though this is not quite what
* you expect of a strict internet domain.
*
* domain = sub-domain *("." sub-domain)
*
* @access private
* @param string $domain The string to check.
* @return mixed False on failure, or the validated domain on success.
*/
function _validateDomain($domain)
{
// Note the different use of $subdomains and $sub_domains
$subdomains = explode('.', $domain);
while (count($subdomains) > 0) {
$sub_domains[] = $this->_splitCheck($subdomains, '.');
for ($i = 0; $i < $this->index + 1; $i++)
array_shift($subdomains);
}
foreach ($sub_domains as $sub_domain) {
if (!$this->_validateSubdomain(trim($sub_domain)))
return false;
}
// Managed to get here, so return input.
return $domain;
}
/**
* Function to validate a subdomain:
* subdomain = domain-ref / domain-literal
*
* @access private
* @param string $subdomain The string to check.
* @return boolean Success or failure.
*/
function _validateSubdomain($subdomain)
{
if (preg_match('|^\[(.*)]$|', $subdomain, $arr)){
if (!$this->_validateDliteral($arr[1])) return false;
} else {
if (!$this->_validateAtom($subdomain)) return false;
}
// Got here, so return successful.
return true;
}
/**
* Function to validate a domain literal:
* domain-literal = "[" *(dtext / quoted-pair) "]"
*
* @access private
* @param string $dliteral The string to check.
* @return boolean Success or failure.
*/
function _validateDliteral($dliteral)
{
return !preg_match('/(.)[][\x0D\\\\]/', $dliteral, $matches) && $matches[1] != '\\';
}
/**
* Function to validate an addr-spec.
*
* addr-spec = local-part "@" domain
*
* @access private
* @param string $addr_spec The string to check.
* @return mixed False on failure, or the validated addr-spec on success.
*/
function _validateAddrSpec($addr_spec)
{
$addr_spec = trim($addr_spec);
// Split on @ sign if there is one.
if (strpos($addr_spec, '@') !== false) {
$parts = explode('@', $addr_spec);
$local_part = $this->_splitCheck($parts, '@');
$domain = substr($addr_spec, strlen($local_part . '@'));
// No @ sign so assume the default domain.
} else {
$local_part = $addr_spec;
$domain = $this->default_domain;
}
if (($local_part = $this->_validateLocalPart($local_part)) === false) return false;
if (($domain = $this->_validateDomain($domain)) === false) return false;
// Got here so return successful.
return array('local_part' => $local_part, 'domain' => $domain);
}
/**
* Function to validate the local part of an address:
* local-part = word *("." word)
*
* @access private
* @param string $local_part
* @return mixed False on failure, or the validated local part on success.
*/
function _validateLocalPart($local_part)
{
$parts = explode('.', $local_part);
$words = array();
// Split the local_part into words.
while (count($parts) > 0){
$words[] = $this->_splitCheck($parts, '.');
for ($i = 0; $i < $this->index + 1; $i++) {
array_shift($parts);
}
}
// Validate each word.
foreach ($words as $word) {
// If this word contains an unquoted space, it is invalid. (6.2.4)
if (strpos($word, ' ') && $word[0] !== '"')
{
return false;
}
if ($this->_validatePhrase(trim($word)) === false) return false;
}
// Managed to get here, so return the input.
return $local_part;
}
/**
* Returns an approximate count of how many addresses are in the
* given string. This is APPROXIMATE as it only splits based on a
* comma which has no preceding backslash. Could be useful as
* large amounts of addresses will end up producing *large*
* structures when used with parseAddressList().
*
* @param string $data Addresses to count
* @return int Approximate count
*/
function approximateCount($data)
{
return count(preg_split('/(?<!\\\\),/', $data));
}
/**
* This is a email validating function separate to the rest of the
* class. It simply validates whether an email is of the common
* internet form: <user>@<domain>. This can be sufficient for most
* people. Optional stricter mode can be utilised which restricts
* mailbox characters allowed to alphanumeric, full stop, hyphen
* and underscore.
*
* @param string $data Address to check
* @param boolean $strict Optional stricter mode
* @return mixed False if it fails, an indexed array
* username/domain if it matches
*/
function isValidInetAddress($data, $strict = false)
{
$regex = $strict ? '/^([.0-9a-z_-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,4})$/i' : '/^([*+!.&#$|\'\\%\/0-9a-z^_`{}=?~:-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,4})$/i';
if (preg_match($regex, trim($data), $matches)) {
return array($matches[1], $matches[2]);
} else {
return false;
}
}
}