1 files changed, 59 insertions, 0 deletions
diff --git a/framework/Web/UI/THiddenFieldPageStatePersister.php b/framework/Web/UI/THiddenFieldPageStatePersister.php
new file mode 100644
index 00000000..d2cb5226
--- /dev/null
+++ b/framework/Web/UI/THiddenFieldPageStatePersister.php
@@ -0,0 +1,59 @@
+<?php
+
+require_once(PRADO_DIR.'/Web/UI/TPageStatePersister.php');
+
+class THiddenFieldPageStatePersister extends TPageStatePersister
+{
+	private $_page;
+
+	public function __construct($page)
+	{
+		$this->_page=$page;
+	}
+
+	public function save($state)
+	{
+		$data=Prado::serialize($state);
+		$hmac=$this->computeHMAC($data,$this->getKey());
+		if(function_exists('gzuncompress') && function_exists('gzcompress'))
+			$data=gzcompress($hmac.$data);
+		else
+			$data=$hmac.$data;
+		$this->_page->saveStateField($data);
+	}
+
+	public function load()
+	{
+		$str=$this->_page->loadStateField();
+		if($str==='')
+			return null;
+		if(function_exists('gzuncompress') && function_exists('gzcompress'))
+			$data=gzuncompress($str);
+		else
+			$data=$str;
+		if($data!==false && strlen($data)>32)
+		{
+			$hmac=substr($data,0,32);
+			$state=substr($data,32);
+			if($hmac===$this->computeHMAC($state,$this->getKey()))
+				return Prado::unserialize($state);
+		}
+		throw new Exception('viewstate data is corrupted.');
+	}
+
+	private function getKey()
+	{
+		return 'abcdefe';
+	}
+
+	private function computeHMAC($data,$key)
+	{
+		if (strlen($key) > 64)
+			$key = pack('H32', md5($key));
+		elseif (strlen($key) < 64)
+			$key = str_pad($key, 64, "\0");
+		return md5((str_repeat("\x5c", 64) ^ substr($key, 0, 64)) . pack('H32', md5((str_repeat("\x36", 64) ^ substr($key, 0, 64)) . $data)));
+	}
+}
+
+?>
+\ No newline at end of file