diff --git a/crates/daemon/src/idm.rs b/crates/daemon/src/idm.rs
index 7525def..ee788b9 100644
--- a/crates/daemon/src/idm.rs
+++ b/crates/daemon/src/idm.rs
@@ -120,16 +120,22 @@ impl DaemonIdm {
                         if let Some(data) = data {
                             let buffer = buffers.entry(domid).or_insert_with_key(|_| BytesMut::new());
                             buffer.extend_from_slice(&data);
-                            if buffer.len() < 4 {
+                            if buffer.len() < 6 {
                                 continue;
                             }
-                            let size = (buffer[0] as u32 | (buffer[1] as u32) << 8 | (buffer[2] as u32) << 16 | (buffer[3] as u32) << 24) as usize;
-                            let needed = size + 4;
+
+                            if buffer[0] != 0xff || buffer[1] != 0xff {
+                                buffer.clear();
+                                continue;
+                            }
+
+                            let size = (buffer[2] as u32 | (buffer[3] as u32) << 8 | (buffer[4] as u32) << 16 | (buffer[5] as u32) << 24) as usize;
+                            let needed = size + 6;
                             if buffer.len() < needed {
                                 continue;
                             }
                             let mut packet = buffer.split_to(needed);
-                            packet.advance(4);
+                            packet.advance(6);
                             match IdmPacket::decode(packet) {
                                 Ok(packet) => {
                                     let _ = client_or_create(domid, &self.tx_sender, &self.clients, &self.feeds).await?;
@@ -159,12 +165,14 @@ impl DaemonIdm {
                 x = self.tx_receiver.recv() => match x {
                     Some((domid, packet)) => {
                         let data = packet.encode_to_vec();
-                        let mut buffer = vec![0u8; 4];
+                        let mut buffer = vec![0u8; 6];
                         let length = data.len() as u32;
-                        buffer[0] = length as u8;
-                        buffer[1] = (length << 8) as u8;
-                        buffer[2] = (length << 16) as u8;
-                        buffer[3] = (length << 24) as u8;
+                        buffer[0] = 0xff;
+                        buffer[1] = 0xff;
+                        buffer[2] = length as u8;
+                        buffer[3] = (length << 8) as u8;
+                        buffer[4] = (length << 16) as u8;
+                        buffer[5] = (length << 24) as u8;
                         buffer.extend_from_slice(&data);
                         self.tx_raw_sender.send((domid, buffer)).await?;
                         let _ = self.snoop_sender.send(DaemonIdmSnoopPacket { from: 0, to: domid, packet });
diff --git a/crates/krata/src/idm/client.rs b/crates/krata/src/idm/client.rs
index c9ac714..3c0181b 100644
--- a/crates/krata/src/idm/client.rs
+++ b/crates/krata/src/idm/client.rs
@@ -69,6 +69,14 @@ impl IdmBackend for IdmFileBackend {
     async fn recv(&mut self) -> Result<IdmPacket> {
         let mut fd = self.read_fd.lock().await;
         let mut guard = fd.readable_mut().await?;
+        let b1 = guard.get_inner_mut().read_u8().await?;
+        if b1 != 0xff {
+            return Ok(IdmPacket::default());
+        }
+        let b2 = guard.get_inner_mut().read_u8().await?;
+        if b2 != 0xff {
+            return Ok(IdmPacket::default());
+        }
         let size = guard.get_inner_mut().read_u32_le().await?;
         if size == 0 {
             return Ok(IdmPacket::default());
@@ -84,6 +92,7 @@ impl IdmBackend for IdmFileBackend {
     async fn send(&mut self, packet: IdmPacket) -> Result<()> {
         let mut file = self.write.lock().await;
         let data = packet.encode_to_vec();
+        file.write_all(&[0xff, 0xff]).await?;
         file.write_u32_le(data.len() as u32).await?;
         file.write_all(&data).await?;
         Ok(())