WIPhash-collision

Signed-off-by: Florian Pritz <bluewind@xinu.at>

1 files changed, 31 insertions, 22 deletions

diff --git a/application/models/mfile.php b/application/models/mfile.php
index eee2c4e5b..d6851a6ef 100644
--- a/application/models/mfile.php
+++ b/application/models/mfile.php
@@ -70,27 +70,30 @@ class Mfile extends CI_Model {
 	function get_filedata($id)
 	{
 		$query = $this->db
-			->select('id, hash, filename, mimetype, date, user, filesize')
+			->select('files.id, hash, hash_collision_counter, filename, mimetype, date, user, filesize')
 			->from('files')
-			->where('id', $id)
+			->join('file_storage', 'file_storage.id = files.file_storage_id')
+			->where('files.id', $id)
 			->limit(1)
 			->get();
 
 		if ($query->num_rows() > 0) {
-			return $query->row_array();
+			$data = $query->row_array();
+			$data["data_id"] = $data["hash"]."-".$data["hash_collision_counter"];
+			return $data;
 		} else {
 			return false;
 		}
 	}
 
-	// return the folder in which the file with $hash is stored
-	function folder($hash) {
-		return $this->config->item('upload_path').'/'.substr($hash, 0, 3);
+	// return the folder in which the file with $data_id is stored
+	function folder($data_id) {
+		return $this->config->item('upload_path').'/'.substr($data_id, 0, 3);
 	}
 
-	// Returns the full path to the file with $hash
-	function file($hash) {
-		return $this->folder($hash).'/'.$hash;
+	// Returns the full path to the file with $data_id
+	function file($data_id) {
+		return $this->folder($data_id).'/'.$data_id;
 	}
 
 	// Return mimetype of file
@@ -136,10 +139,10 @@ class Mfile extends CI_Model {
 		if (!$filedata) {
 			return false;
 		}
-		$file = $this->file($filedata['hash']);
+		$file = $this->file($filedata['data_id']);
 
 		if (!file_exists($file)) {
-			$this->delete_hash($filedata["hash"]);
+			$this->delete_data_id($filedata["data_id"]);
 			return false;
 		}
 
@@ -158,7 +161,7 @@ class Mfile extends CI_Model {
 			// if the file has been uploaded multiple times the mtime is the time
 			// of the last upload
 			if (filemtime($file) < $remove_before) {
-				$this->delete_hash($filedata["hash"]);
+				$this->delete_data_id($filedata["data_id"]);
 			} else {
 				$this->delete_id($id);
 			}
@@ -171,7 +174,7 @@ class Mfile extends CI_Model {
 	public function get_timeout($id)
 	{
 		$filedata = $this->get_filedata($id);
-		$file = $this->file($filedata["hash"]);
+		$file = $this->file($filedata["data_id"]);
 
 		if ($this->config->item("upload_max_age") == 0) {
 			return -1;
@@ -195,11 +198,14 @@ class Mfile extends CI_Model {
 		}
 	}
 
-	private function unused_file($hash)
+	private function unused_file($data_id)
 	{
-		$query = $this->db->select('id')
+		list ($hash, $hash_collision_counter) = explode("-", $data_id);
+		$query = $this->db->select('files.id')
 			->from('files')
+			->join('file_storage', 'file_storage.id = files.file_storage_id')
 			->where('hash', $hash)
+			->where('hash_collision_counter', $hash_collision_counter)
 			->limit(1)
 			->get();
 
@@ -238,12 +244,12 @@ class Mfile extends CI_Model {
 		}
 
 		if ($filedata !== false) {
-			assert(isset($filedata["hash"]));
-			if ($this->unused_file($filedata['hash'])) {
-				if (file_exists($this->file($filedata['hash']))) {
-					unlink($this->file($filedata['hash']));
+			assert(isset($filedata["data_id"]));
+			if ($this->unused_file($filedata['data_id'])) {
+				if (file_exists($this->file($filedata['data_id']))) {
+					unlink($this->file($filedata['data_id']));
 				}
-				$dir = $this->folder($filedata['hash']);
+				$dir = $this->folder($filedata['data_id']);
 				if (file_exists($dir)) {
 					if (count(scandir($dir)) == 2) {
 						rmdir($dir);
@@ -254,11 +260,14 @@ class Mfile extends CI_Model {
 		return true;
 	}
 
-	public function delete_hash($hash)
+	public function delete_data_id($data_id)
 	{
-		$ids = $this->db->select('id')
+		list ($hash, $hash_collision_counter) = explode("-", $data_id);
+		$ids = $this->db->select('files.id')
 			->from('files')
+			->join('file_storage', 'file_storage.id = files.file_storage_id')
 			->where('hash', $hash)
+			->where('hash_collision_counter', $hash_collision_counter)
 			->get()->result_array();
 
 		foreach ($ids as $entry) {