ILIAS  release_5-3 Revision v5.3.23-19-g915713cf615
RFC822.php
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1 <?php
71 {
72 
77  public $address = '';
78 
83  public $default_domain = 'localhost';
84 
89  public $nestGroups = true;
90 
95  public $validate = true;
96 
101  public $addresses = array();
102 
107  public $structure = array();
108 
113  public $error = null;
114 
119  public $index = null;
120 
126  public $num_groups = 0;
127 
133  public $mailRFC822 = true;
134 
139  public $limit = null;
140 
153  // php7-workaround alex: constructor
154  public function __construct($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
155  {
156  if (isset($address)) {
157  $this->address = $address;
158  }
159  if (isset($default_domain)) {
160  $this->default_domain = $default_domain;
161  }
162  if (isset($nest_groups)) {
163  $this->nestGroups = $nest_groups;
164  }
165  if (isset($validate)) {
166  $this->validate = $validate;
167  }
168  if (isset($limit)) {
169  $this->limit = $limit;
170  }
171  }
172 
185  public function parseAddressList($address = null, $default_domain = null, $nest_groups = null, $validate = null, $limit = null)
186  {
187  if (!isset($this) || !isset($this->mailRFC822)) {
188  $obj = new Mail_RFC822($address, $default_domain, $nest_groups, $validate, $limit);
189  return $obj->parseAddressList();
190  }
191 
192  if (isset($address)) {
193  $this->address = $address;
194  }
195  if (isset($default_domain)) {
196  $this->default_domain = $default_domain;
197  }
198  if (isset($nest_groups)) {
199  $this->nestGroups = $nest_groups;
200  }
201  if (isset($validate)) {
202  $this->validate = $validate;
203  }
204  if (isset($limit)) {
205  $this->limit = $limit;
206  }
207 
208  $this->structure = array();
209  $this->addresses = array();
210  $this->error = null;
211  $this->index = null;
212 
213  // Unfold any long lines in $this->address.
214  $this->address = preg_replace('/\r?\n/', "\r\n", $this->address);
215  $this->address = preg_replace('/\r\n(\t| )+/', ' ', $this->address);
216 
217  while ($this->address = $this->_splitAddresses($this->address));
218 
219  if ($this->address === false || isset($this->error)) {
220  // mjansen patch 14 Ap 2016 start
221  require_once 'Services/Mail/exceptions/class.ilMailException.php';
222  throw new ilMailException($this->error);
223  // mjansen patch 14 Ap 2016 end
224  }
225 
226  // Validate each address individually. If we encounter an invalid
227  // address, stop iterating and return an error immediately.
228  foreach ($this->addresses as $address) {
229  $valid = $this->_validateAddress($address);
230 
231  if ($valid === false || isset($this->error)) {
232  // mjansen patch 14 Ap 2016 start
233  require_once 'Services/Mail/exceptions/class.ilMailException.php';
234  throw new ilMailException($this->error);
235  // mjansen patch 14 Ap 2016 end
236  }
237 
238  if (!$this->nestGroups) {
239  $this->structure = array_merge($this->structure, $valid);
240  } else {
241  $this->structure[] = $valid;
242  }
243  }
244 
245  return $this->structure;
246  }
247 
255  public function _splitAddresses($address)
256  {
257  if (!empty($this->limit) && count($this->addresses) == $this->limit) {
258  return '';
259  }
260 
261  if ($this->_isGroup($address) && !isset($this->error)) {
262  $split_char = ';';
263  $is_group = true;
264  } elseif (!isset($this->error)) {
265  $split_char = ',';
266  $is_group = false;
267  } elseif (isset($this->error)) {
268  return false;
269  }
270 
271  // Split the string based on the above ten or so lines.
272  $parts = explode($split_char, $address);
273  $string = $this->_splitCheck($parts, $split_char);
274 
275  // If a group...
276  if ($is_group) {
277  // If $string does not contain a colon outside of
278  // brackets/quotes etc then something's fubar.
279 
280  // First check there's a colon at all:
281  if (strpos($string, ':') === false) {
282  $this->error = 'Invalid address: ' . $string;
283  return false;
284  }
285 
286  // Now check it's outside of brackets/quotes:
287  if (!$this->_splitCheck(explode(':', $string), ':')) {
288  return false;
289  }
290 
291  // We must have a group at this point, so increase the counter:
292  $this->num_groups++;
293  }
294 
295  // $string now contains the first full address/group.
296  // Add to the addresses array.
297  $this->addresses[] = array(
298  'address' => trim($string),
299  'group' => $is_group
300  );
301 
302  // Remove the now stored address from the initial line, the +1
303  // is to account for the explode character.
304  $address = trim(substr($address, strlen($string) + 1));
305 
306  // If the next char is a comma and this was a group, then
307  // there are more addresses, otherwise, if there are any more
308  // chars, then there is another address.
309  if ($is_group && substr($address, 0, 1) == ',') {
310  $address = trim(substr($address, 1));
311  return $address;
312  } elseif (strlen($address) > 0) {
313  return $address;
314  } else {
315  return '';
316  }
317 
318  // If you got here then something's off
319  return false;
320  }
321 
329  public function _isGroup($address)
330  {
331  // First comma not in quotes, angles or escaped:
332  $parts = explode(',', $address);
333  $string = $this->_splitCheck($parts, ',');
334 
335  // Now we have the first address, we can reliably check for a
336  // group by searching for a colon that's not escaped or in
337  // quotes or angle brackets.
338  if (count($parts = explode(':', $string)) > 1) {
339  $string2 = $this->_splitCheck($parts, ':');
340  return ($string2 !== $string);
341  } else {
342  return false;
343  }
344  }
345 
354  public function _splitCheck($parts, $char)
355  {
356  $string = $parts[0];
357 
358  for ($i = 0; $i < count($parts); $i++) {
359  if ($this->_hasUnclosedQuotes($string)
360  || $this->_hasUnclosedBrackets($string, '<>')
361  || $this->_hasUnclosedBrackets($string, '[]')
362  || $this->_hasUnclosedBrackets($string, '()')
363  || substr($string, -1) == '\\') {
364  if (isset($parts[$i + 1])) {
365  $string = $string . $char . $parts[$i + 1];
366  } else {
367  $this->error = 'Invalid address spec. Unclosed bracket or quotes';
368  return false;
369  }
370  } else {
371  $this->index = $i;
372  break;
373  }
374  }
375 
376  return $string;
377  }
378 
387  public function _hasUnclosedQuotes($string)
388  {
389  $string = trim($string);
390  $iMax = strlen($string);
391  $in_quote = false;
392  $i = $slashes = 0;
393 
394  for (; $i < $iMax; ++$i) {
395  switch ($string[$i]) {
396  case '\\':
397  ++$slashes;
398  break;
399 
400  case '"':
401  if ($slashes % 2 == 0) {
402  $in_quote = !$in_quote;
403  }
404  // Fall through to default action below.
405 
406  // no break
407  default:
408  $slashes = 0;
409  break;
410  }
411  }
412 
413  return $in_quote;
414  }
415 
425  public function _hasUnclosedBrackets($string, $chars)
426  {
427  $num_angle_start = substr_count($string, $chars[0]);
428  $num_angle_end = substr_count($string, $chars[1]);
429 
430  $this->_hasUnclosedBracketsSub($string, $num_angle_start, $chars[0]);
431  $this->_hasUnclosedBracketsSub($string, $num_angle_end, $chars[1]);
432 
433  if ($num_angle_start < $num_angle_end) {
434  $this->error = 'Invalid address spec. Unmatched quote or bracket (' . $chars . ')';
435  return false;
436  } else {
437  return ($num_angle_start > $num_angle_end);
438  }
439  }
440 
450  public function _hasUnclosedBracketsSub($string, &$num, $char)
451  {
452  $parts = explode($char, $string);
453  for ($i = 0; $i < count($parts); $i++) {
454  if (substr($parts[$i], -1) == '\\' || $this->_hasUnclosedQuotes($parts[$i])) {
455  $num--;
456  }
457  if (isset($parts[$i + 1])) {
458  $parts[$i + 1] = $parts[$i] . $char . $parts[$i + 1];
459  }
460  }
461 
462  return $num;
463  }
464 
472  public function _validateAddress($address)
473  {
474  $is_group = false;
475  $addresses = array();
476 
477  if ($address['group']) {
478  $is_group = true;
479 
480  // Get the group part of the name
481  $parts = explode(':', $address['address']);
482  $groupname = $this->_splitCheck($parts, ':');
483  $structure = array();
484 
485  // And validate the group part of the name.
486  if (!$this->_validatePhrase($groupname)) {
487  $this->error = 'Group name did not validate.';
488  return false;
489  } else {
490  // Don't include groups if we are not nesting
491  // them. This avoids returning invalid addresses.
492  if ($this->nestGroups) {
493  $structure = new stdClass;
494  $structure->groupname = $groupname;
495  }
496  }
497 
498  $address['address'] = ltrim(substr($address['address'], strlen($groupname . ':')));
499  }
500 
501  // If a group then split on comma and put into an array.
502  // Otherwise, Just put the whole address in an array.
503  if ($is_group) {
504  while (strlen($address['address']) > 0) {
505  $parts = explode(',', $address['address']);
506  $addresses[] = $this->_splitCheck($parts, ',');
507  $address['address'] = trim(substr($address['address'], strlen(end($addresses) . ',')));
508  }
509  } else {
510  $addresses[] = $address['address'];
511  }
512 
513  // Check that $addresses is set, if address like this:
514  // Groupname:;
515  // Then errors were appearing.
516  if (!count($addresses)) {
517  $this->error = 'Empty group.';
518  return false;
519  }
520 
521  // Trim the whitespace from all of the address strings.
522  array_map('trim', $addresses);
523 
524  // Validate each mailbox.
525  // Format could be one of: name <geezer@domain.com>
526  // geezer@domain.com
527  // geezer
528  // ... or any other format valid by RFC 822.
529  for ($i = 0; $i < count($addresses); $i++) {
530  if (!$this->validateMailbox($addresses[$i])) {
531  if (empty($this->error)) {
532  $this->error = 'Validation failed for: ' . $addresses[$i];
533  }
534  return false;
535  }
536  }
537 
538  // Nested format
539  if ($this->nestGroups) {
540  if ($is_group) {
541  $structure->addresses = $addresses;
542  } else {
543  $structure = $addresses[0];
544  }
545 
546  // Flat format
547  } else {
548  if ($is_group) {
549  $structure = array_merge($structure, $addresses);
550  } else {
552  }
553  }
554 
555  return $structure;
556  }
557 
565  public function _validatePhrase($phrase)
566  {
567  // Splits on one or more Tab or space.
568  $parts = preg_split('/[ \\x09]+/', $phrase, -1, PREG_SPLIT_NO_EMPTY);
569 
570  $phrase_parts = array();
571  while (count($parts) > 0) {
572  $phrase_parts[] = $this->_splitCheck($parts, ' ');
573  for ($i = 0; $i < $this->index + 1; $i++) {
574  array_shift($parts);
575  }
576  }
577 
578  foreach ($phrase_parts as $part) {
579  // If quoted string:
580  if (substr($part, 0, 1) == '"') {
581  if (!$this->_validateQuotedString($part)) {
582  return false;
583  }
584  continue;
585  }
586 
587  // Otherwise it's an atom:
588  if (!$this->_validateAtom($part)) {
589  return false;
590  }
591  }
592 
593  return true;
594  }
595 
609  public function _validateAtom($atom)
610  {
611  if (!$this->validate) {
612  // Validation has been turned off; assume the atom is okay.
613  return true;
614  }
615 
616  // Check for any char from ASCII 0 - ASCII 127
617  // mjansen patch 16 Sep 2015 start
618  // Check for specials:
619  if (preg_match('/[][()<>@,;\\:". ]/', $atom)) {
620  return false;
621  }
622 
623  // Check for control characters (ASCII 0-31):
624  if (preg_match('/[\\x00-\\x1F]+/', $atom)) {
625  return false;
626  }
627  #16291
628  #17618
629  if (!(bool) preg_match('//u', $atom)) {
630  return false;
631  }
632  // mjansen patch 16 Sep 2015 end
633 
634  return true;
635  }
636 
645  public function _validateQuotedString($qstring)
646  {
647  // Leading and trailing "
648  $qstring = substr($qstring, 1, -1);
649 
650  // Perform check, removing quoted characters first.
651  return !preg_match('/[\x0D\\\\"]/', preg_replace('/\\\\./', '', $qstring));
652  }
653 
663  public function validateMailbox(&$mailbox)
664  {
665  // A couple of defaults.
666  $phrase = '';
667  $comment = '';
668  $comments = array();
669 
670  // Catch any RFC822 comments and store them separately.
671  $_mailbox = $mailbox;
672  while (strlen(trim($_mailbox)) > 0) {
673  $parts = explode('(', $_mailbox);
674  $before_comment = $this->_splitCheck($parts, '(');
675  if ($before_comment != $_mailbox) {
676  // First char should be a (.
677  $comment = substr(str_replace($before_comment, '', $_mailbox), 1);
678  $parts = explode(')', $comment);
679  $comment = $this->_splitCheck($parts, ')');
680  $comments[] = $comment;
681 
682  // +2 is for the brackets
683  $_mailbox = substr($_mailbox, strpos($_mailbox, '(' . $comment)+strlen($comment)+2);
684  } else {
685  break;
686  }
687  }
688 
689  foreach ($comments as $comment) {
690  $mailbox = str_replace("($comment)", '', $mailbox);
691  }
692 
693  $mailbox = trim($mailbox);
694 
695  // Check for name + route-addr
696  if (substr($mailbox, -1) == '>' && substr($mailbox, 0, 1) != '<') {
697  $parts = explode('<', $mailbox);
698  $name = $this->_splitCheck($parts, '<');
699 
700  $phrase = trim($name);
701  $route_addr = trim(substr($mailbox, strlen($name . '<'), -1));
702 
703  if ($this->_validatePhrase($phrase) === false || ($route_addr = $this->_validateRouteAddr($route_addr)) === false) {
704  return false;
705  }
706 
707  // Only got addr-spec
708  } else {
709  // First snip angle brackets if present.
710  if (substr($mailbox, 0, 1) == '<' && substr($mailbox, -1) == '>') {
711  $addr_spec = substr($mailbox, 1, -1);
712  } else {
713  $addr_spec = $mailbox;
714  }
715 
716  if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
717  return false;
718  }
719  }
720 
721  // Construct the object that will be returned.
722  $mbox = new stdClass();
723 
724  // Add the phrase (even if empty) and comments
725  $mbox->personal = $phrase;
726  $mbox->comment = isset($comments) ? $comments : array();
727 
728  if (isset($route_addr)) {
729  $mbox->mailbox = $route_addr['local_part'];
730  $mbox->host = $route_addr['domain'];
731  $route_addr['adl'] !== '' ? $mbox->adl = $route_addr['adl'] : '';
732  } else {
733  $mbox->mailbox = $addr_spec['local_part'];
734  $mbox->host = $addr_spec['domain'];
735  }
736 
737  $mailbox = $mbox;
738  return true;
739  }
740 
752  public function _validateRouteAddr($route_addr)
753  {
754  // Check for colon.
755  if (strpos($route_addr, ':') !== false) {
756  $parts = explode(':', $route_addr);
757  $route = $this->_splitCheck($parts, ':');
758  } else {
759  $route = $route_addr;
760  }
761 
762  // If $route is same as $route_addr then the colon was in
763  // quotes or brackets or, of course, non existent.
764  if ($route === $route_addr) {
765  unset($route);
766  $addr_spec = $route_addr;
767  if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
768  return false;
769  }
770  } else {
771  // Validate route part.
772  if (($route = $this->_validateRoute($route)) === false) {
773  return false;
774  }
775 
776  $addr_spec = substr($route_addr, strlen($route . ':'));
777 
778  // Validate addr-spec part.
779  if (($addr_spec = $this->_validateAddrSpec($addr_spec)) === false) {
780  return false;
781  }
782  }
783 
784  if (isset($route)) {
785  $return['adl'] = $route;
786  } else {
787  $return['adl'] = '';
788  }
789 
790  $return = array_merge($return, $addr_spec);
791  return $return;
792  }
793 
802  public function _validateRoute($route)
803  {
804  // Split on comma.
805  $domains = explode(',', trim($route));
806 
807  foreach ($domains as $domain) {
808  $domain = str_replace('@', '', trim($domain));
809  if (!$this->_validateDomain($domain)) {
810  return false;
811  }
812  }
813 
814  return $route;
815  }
816 
827  public function _validateDomain($domain)
828  {
829  // Note the different use of $subdomains and $sub_domains
830  $subdomains = explode('.', $domain);
831 
832  while (count($subdomains) > 0) {
833  $sub_domains[] = $this->_splitCheck($subdomains, '.');
834  for ($i = 0; $i < $this->index + 1; $i++) {
835  array_shift($subdomains);
836  }
837  }
838 
839  foreach ($sub_domains as $sub_domain) {
840  if (!$this->_validateSubdomain(trim($sub_domain))) {
841  return false;
842  }
843  }
844 
845  // Managed to get here, so return input.
846  return $domain;
847  }
848 
857  public function _validateSubdomain($subdomain)
858  {
859  if (preg_match('|^\[(.*)]$|', $subdomain, $arr)) {
860  if (!$this->_validateDliteral($arr[1])) {
861  return false;
862  }
863  } else {
864  if (!$this->_validateAtom($subdomain)) {
865  return false;
866  }
867  }
868 
869  // Got here, so return successful.
870  return true;
871  }
872 
881  public function _validateDliteral($dliteral)
882  {
883  return !preg_match('/(.)[][\x0D\\\\]/', $dliteral, $matches) && $matches[1] != '\\';
884  }
885 
895  public function _validateAddrSpec($addr_spec)
896  {
897  $addr_spec = trim($addr_spec);
898 
899  // mjansen patch 16 Sep 2016 start
900  $validateState = $this->validate;
901  // mjansen patch 16 Sep 2016 end
902  // Split on @ sign if there is one.
903  if (strpos($addr_spec, '@') !== false) {
904  $parts = explode('@', $addr_spec);
905  $local_part = $this->_splitCheck($parts, '@');
906  $domain = substr($addr_spec, strlen($local_part . '@'));
907  // mjansen patch 16 Sep 2016 start
908  if (substr_count($addr_spec, '@') != 1 && $local_part == '') {
909  $this->validate = false;
910  $local_part = $addr_spec;
912  }
913  // mjansen patch 16 Sep 2016 end
914  // No @ sign so assume the default domain.
915  } else {
916  $local_part = $addr_spec;
918  }
919 
920  if (($local_part = $this->_validateLocalPart($local_part)) === false) {
921  return false;
922  }
923  // mjansen patch 16 Sep 2016 start
924  if ($validateState != $this->validate) {
925  $this->validate = $validateState;
926  }
927  // mjansen patch 16 Sep 2016 end
928  if (($domain = $this->_validateDomain($domain)) === false) {
929  return false;
930  }
931 
932  // Got here so return successful.
933  return array('local_part' => $local_part, 'domain' => $domain);
934  }
935 
944  public function _validateLocalPart($local_part)
945  {
946  $parts = explode('.', $local_part);
947  $words = array();
948 
949  // Split the local_part into words.
950  while (count($parts) > 0) {
951  $words[] = $this->_splitCheck($parts, '.');
952  for ($i = 0; $i < $this->index + 1; $i++) {
953  array_shift($parts);
954  }
955  }
956 
957  // Validate each word.
958  foreach ($words as $word) {
959  // If this word contains an unquoted space, it is invalid. (6.2.4)
960  if (strpos($word, ' ') && $word[0] !== '"') {
961  // mjansen patch 24 Feb 2016 start
962  // Mantis issue #18018
963  // # http://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx/
964  //return false;
965  // mjansen patch 24 Feb 2016 end
966  }
967 
968  if ($this->_validatePhrase(trim($word)) === false) {
969  return false;
970  }
971  }
972 
973  // Managed to get here, so return the input.
974  return $local_part;
975  }
976 
987  public function approximateCount($data)
988  {
989  return count(preg_split('/(?<!\\\\),/', $data));
990  }
991 
1005  public function isValidInetAddress($data, $strict = false)
1006  {
1007  $regex = $strict ? '/^([.0-9a-z_+-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})$/i' : '/^([*+!.&#$|\'\\%\/0-9a-z^_`{}=?~:-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})$/i';
1008  if (preg_match($regex, trim($data), $matches)) {
1009  return array($matches[1], $matches[2]);
1010  } else {
1011  return false;
1012  }
1013  }
1014 }
$index
An internal counter/pointer.
Definition: RFC822.php:119
_validateDliteral($dliteral)
Function to validate a domain literal: domain-literal = "[" *(dtext / quoted-pair) "]"...
Definition: RFC822.php:881
$validate
Whether or not to validate atoms for non-ascii characters.
Definition: RFC822.php:95
_hasUnclosedBrackets($string, $chars)
Checks if a string has an unclosed brackets or not.
Definition: RFC822.php:425
_validateRoute($route)
Function to validate a route, which is: route = 1#("@" domain) ":".
Definition: RFC822.php:802
_validateAddrSpec($addr_spec)
Function to validate an addr-spec.
Definition: RFC822.php:895
$valid
$default_domain
The default domain to use for unqualified addresses.
Definition: RFC822.php:83
_hasUnclosedBracketsSub($string, &$num, $char)
Sub function that is used only by hasUnclosedBrackets().
Definition: RFC822.php:450
Class ilMailException.
parseAddressList($address=null, $default_domain=null, $nest_groups=null, $validate=null, $limit=null)
Starts the whole process.
Definition: RFC822.php:185
_validateAddress($address)
Function to begin checking the address.
Definition: RFC822.php:472
_validateDomain($domain)
Function to validate a domain, though this is not quite what you expect of a strict internet domain...
Definition: RFC822.php:827
$structure
The final array of parsed address information that we build up.
Definition: RFC822.php:107
_splitCheck($parts, $char)
A common function that will check an exploded string.
Definition: RFC822.php:354
if($format !==null) $name
Definition: metadata.php:146
_validatePhrase($phrase)
Function to validate a phrase.
Definition: RFC822.php:565
$limit
A limit after which processing stops.
Definition: RFC822.php:139
$error
The current error message, if any.
Definition: RFC822.php:113
_splitAddresses($address)
Splits an address into separate addresses.
Definition: RFC822.php:255
_validateRouteAddr($route_addr)
This function validates a route-addr which is: route-addr = "<" [route] addr-spec ">"...
Definition: RFC822.php:752
_validateQuotedString($qstring)
Function to validate quoted string, which is: quoted-string = <"> *(qtext/quoted-pair) <"> ...
Definition: RFC822.php:645
$num_groups
The number of groups that have been found in the address list.
Definition: RFC822.php:126
approximateCount($data)
Returns an approximate count of how many addresses are in the given string.
Definition: RFC822.php:987
_hasUnclosedQuotes($string)
Checks if a string has unclosed quotes or not.
Definition: RFC822.php:387
validateMailbox(&$mailbox)
Function to validate a mailbox, which is: mailbox = addr-spec ; simple address / phrase route-addr ; ...
Definition: RFC822.php:663
$comment
Definition: buildRTE.php:83
Create styles array
The data for the language used.
_validateLocalPart($local_part)
Function to validate the local part of an address: local-part = word *("." word)
Definition: RFC822.php:944
$mailRFC822
A variable so that we can tell whether or not we&#39;re inside a Mail_RFC822 object.
Definition: RFC822.php:133
$address
The address being parsed by the RFC822 object.
Definition: RFC822.php:77
isValidInetAddress($data, $strict=false)
This is a email validating function separate to the rest of the class.
Definition: RFC822.php:1005
$nestGroups
Should we return a nested array showing groups, or flatten everything?
Definition: RFC822.php:89
$i
Definition: disco.tpl.php:19
_isGroup($address)
Checks for a group at the start of the string.
Definition: RFC822.php:329
if(!array_key_exists('domain', $_REQUEST)) $domain
Definition: resume.php:8
__construct($address=null, $default_domain=null, $nest_groups=null, $validate=null, $limit=null)
Sets up the object.
Definition: RFC822.php:154
_validateSubdomain($subdomain)
Function to validate a subdomain: subdomain = domain-ref / domain-literal.
Definition: RFC822.php:857
$addresses
The array of raw addresses built up as we parse.
Definition: RFC822.php:101
_validateAtom($atom)
Function to validate an atom which from rfc822 is: atom = 1*<any CHAR except specials, SPACE and CTLs>
Definition: RFC822.php:609