[21186] New feature: email address validator 4746:5203

Revision: 21186
          http://svn.sv.gnu.org/viewvc/?view=rev&root=phpgroupware&revision=21186
Author:   sigurdne
Date:     2010-04-14 19:07:28 +0000 (Wed, 14 Apr 2010)
Log Message:
-----------
New feature: email address validator 4746:5203

Added Paths:
-----------
    people/sigurdne/modules/phpgwapi/trunk/inc/class.EmailAddressValidator.inc.php

Added: people/sigurdne/modules/phpgwapi/trunk/inc/class.EmailAddressValidator.inc.php
===================================================================
--- people/sigurdne/modules/phpgwapi/trunk/inc/class.EmailAddressValidator.inc.php	                        (rev 0)
+++ people/sigurdne/modules/phpgwapi/trunk/inc/class.EmailAddressValidator.inc.php	2010-04-14 19:07:28 UTC (rev 21186)
@@ -0,0 +1,207 @@
+<?php
+
+	/*
+
+		EmailAddressValidator Class
+		http://code.google.com/p/php-email-address-validation/
+
+		Released under New BSD license
+		http://www.opensource.org/licenses/bsd-license.php
+	   
+		Sample Code
+		----------------
+		$validator = new EmailAddressValidator;
+		if ($validator->check_email_address('[email protected]'))
+		{
+			// Email address is technically valid
+		}
+
+	*/
+
+	class phpgwapi_EmailAddressValidator
+	{
+
+		/**
+		 * Check email address validity
+		 * @param   strEmailAddress     Email address to be checked
+		 * @return  True if email is valid, false if not
+		 */
+		public function check_email_address($strEmailAddress)
+		{
+		   
+			// If magic quotes is "on", email addresses with quote marks will
+			// fail validation because of added escape characters. Uncommenting
+			// the next three lines will allow for this issue.
+			//if (get_magic_quotes_gpc())
+			//{
+			//    $strEmailAddress = stripslashes($strEmailAddress);
+			//}
+
+			// Control characters are not allowed
+			if (preg_match('/[\x00-\x1F\x7F-\xFF]/', $strEmailAddress))
+			{
+				return false;
+			}
+
+			// Check email length - min 3 (a@a), max 256
+			if (!$this->check_text_length($strEmailAddress, 3, 256))
+			{
+				return false;
+			}
+
+			// Split it into sections using last instance of "@"
+			$intAtSymbol = strrpos($strEmailAddress, '@');
+			if ($intAtSymbol === false)
+			{
+				// No "@" symbol in email.
+				return false;
+			}
+			$arrEmailAddress[0] = substr($strEmailAddress, 0, $intAtSymbol);
+			$arrEmailAddress[1] = substr($strEmailAddress, $intAtSymbol + 1);
+
+			// Count the "@" symbols. Only one is allowed, except where
+			// contained in quote marks in the local part. Quickest way to
+			// check this is to remove anything in quotes. We also remove
+			// characters escaped with backslash, and the backslash
+			// character.
+			$arrTempAddress[0] = preg_replace('/\./'
+											 ,''
+											 ,$arrEmailAddress[0]);
+			$arrTempAddress[0] = preg_replace('/"[^"]+"/'
+											 ,''
+											 ,$arrTempAddress[0]);
+			$arrTempAddress[1] = $arrEmailAddress[1];
+			$strTempAddress = $arrTempAddress[0] . $arrTempAddress[1];
+			// Then check - should be no "@" symbols.
+			if (strrpos($strTempAddress, '@') !== false)
+			{
+				// "@" symbol found
+				return false;
+			}
+
+			// Check local portion
+			if (!$this->check_local_portion($arrEmailAddress[0]))
+			{
+				return false;
+			}
+
+			// Check domain portion
+			if (!$this->check_domain_portion($arrEmailAddress[1]))
+			{
+				return false;
+			}
+
+			// If we're still here, all checks above passed. Email is valid.
+			return true;
+
+		}
+
+		/**
+		 * Checks email section before "@" symbol for validity
+		 * @param   strLocalPortion     Text to be checked
+		 * @return  True if local portion is valid, false if not
+		 */
+		protected function check_local_portion($strLocalPortion)
+		{
+			// Local portion can only be from 1 to 64 characters, inclusive.
+			// Please note that servers are encouraged to accept longer local
+			// parts than 64 characters.
+			if (!$this->check_text_length($strLocalPortion, 1, 64))
+			{
+				return false;
+			}
+			// Local portion must be:
+			// 1) a dot-atom (strings separated by periods)
+			// 2) a quoted string
+			// 3) an obsolete format string (combination of the above)
+			$arrLocalPortion = explode('.', $strLocalPortion);
+			for ($i = 0, $max = sizeof($arrLocalPortion); $i < $max; $i++)
+			{
+				 if (!preg_match('.^('
+								.    '([A-Za-z0-9!#$%&\'*+/=?^_`{|}~-]'
+								.    '[A-Za-z0-9!#$%&\'*+/=?^_`{|}~-]{0,63})'
+								.'|'
+								.    '("[^\\\"]{0,62}")'
+								.')$.'
+								,$arrLocalPortion[$i]))
+				{
+					return false;
+				}
+			}
+			return true;
+		}
+
+		/**
+		 * Checks email section after "@" symbol for validity
+		 * @param   strDomainPortion     Text to be checked
+		 * @return  True if domain portion is valid, false if not
+		 */
+		protected function check_domain_portion($strDomainPortion)
+		{
+			// Total domain can only be from 1 to 255 characters, inclusive
+			if (!$this->check_text_length($strDomainPortion, 1, 255))
+			{
+				return false;
+			}
+			// Check if domain is IP, possibly enclosed in square brackets.
+			if (preg_match('/^(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])'
+			   .'(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}$/'
+			   ,$strDomainPortion) ||
+				preg_match('/^\[(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])'
+			   .'(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}\]$/'
+			   ,$strDomainPortion))
+			{
+				return true;
+			}
+			else
+			{
+				$arrDomainPortion = explode('.', $strDomainPortion);
+				if (sizeof($arrDomainPortion) < 2)
+				{
+					return false; // Not enough parts to domain
+				}
+				for ($i = 0, $max = sizeof($arrDomainPortion); $i < $max; $i++)
+				{
+					// Each portion must be between 1 and 63 characters, inclusive
+					if (!$this->check_text_length($arrDomainPortion[$i], 1, 63))
+					{
+						return false;
+					}
+					if (!preg_match('/^(([A-Za-z0-9][A-Za-z0-9-]{0,61}[A-Za-z0-9])|'
+					   .'([A-Za-z0-9]+))$/', $arrDomainPortion[$i]))
+					{
+						return false;
+					}
+					if ($i == $max - 1)
+					{ // TLD cannot be only numbers
+						if (strlen(preg_replace('/[0-9]/', '', $arrDomainPortion[$i])) <= 0)
+						{
+							return false;
+						}
+					}
+				}
+			}
+			return true;
+		}
+
+		/**
+		 * Check given text length is between defined bounds
+		 * @param   strText     Text to be checked
+		 * @param   intMinimum  Minimum acceptable length
+		 * @param   intMaximum  Maximum acceptable length
+		 * @return  True if string is within bounds (inclusive), false if not
+		 */
+		protected function check_text_length($strText, $intMinimum, $intMaximum)
+		{
+			// Minimum and maximum are both inclusive
+			$intTextLength = strlen($strText);
+			if (($intTextLength < $intMinimum) || ($intTextLength > $intMaximum))
+			{
+				return false;
+			}
+			else
+			{
+				return true;
+			}
+		}
+	}