feat(dvc): close channel API for server and client

crates/ironrdp-dvc/src/client.rs

@@ -167,6 +167,11 @@ impl DrdynvcClient {
         self.cap_handshake_done = true;
         SvcMessage::from(caps_response)
     }
+
+    pub fn close_channel(&mut self, channel_id: u32) -> SvcMessage {
+        self.dynamic_channels.remove_by_channel_id(channel_id);
+        SvcMessage::from(DrdynvcClientPdu::Close(ClosePdu::new(channel_id)))
+    }
 }
 
 impl_as_any!(DrdynvcClient);
@@ -227,14 +232,14 @@ impl SvcProcessor for DrdynvcClient {
                     );
                 }
             }
-            DrdynvcServerPdu::Close(close_request) => {
-                debug!("Got DVC Close Request PDU: {close_request:?}");
-                self.dynamic_channels.remove_by_channel_id(close_request.channel_id());
-
-                let close_response = DrdynvcClientPdu::Close(ClosePdu::new(close_request.channel_id()));
-
-                debug!("Send DVC Close Response PDU: {close_response:?}");
-                responses.push(SvcMessage::from(close_response));
+            DrdynvcServerPdu::Close(close) => {
+                debug!("Got DVC Close PDU: {close:?}");
+                let channel_id = close.channel_id();
+                if self.dynamic_channels.remove_by_channel_id(channel_id).is_some() {
+                    let close_response = DrdynvcClientPdu::Close(ClosePdu::new(channel_id));
+                    debug!("Send DVC Close Response PDU: {close_response:?}");
+                    responses.push(SvcMessage::from(close_response));
+                }
             }
             DrdynvcServerPdu::Data(data) => {
                 let channel_id = data.channel_id();
@@ -337,8 +342,8 @@ impl DynamicChannelSet {
         self.active_channels.get_mut(&id)
     }
 
-    fn remove_by_channel_id(&mut self, id: DynamicChannelId) {
-        if let Some(dvc) = self.active_channels.remove(&id) {
+    fn remove_by_channel_id(&mut self, id: DynamicChannelId) -> Option<DynamicVirtualChannel> {
+        self.active_channels.remove(&id).inspect(|dvc| {
             let type_id = dvc.processor_type_id();
 
             // Only matters for pre-registered channels
@@ -347,7 +352,7 @@ impl DynamicChannelSet {
             {
                 entry.remove();
             }
-        }
+        })
     }
 
     #[inline]

crates/ironrdp-dvc/src/lib.rs

@@ -109,6 +109,14 @@ pub struct DynamicVirtualChannel {
     channel_id: Option<DynamicChannelId>,
 }
 
+impl Drop for DynamicVirtualChannel {
+    fn drop(&mut self) {
+        if let Some(id) = self.channel_id {
+            self.channel_processor.close(id);
+        }
+    }
+}
+
 impl DynamicVirtualChannel {
     fn from_boxed(processor: Box<dyn DvcProcessor + Send>) -> Self {
         Self {

crates/ironrdp-dvc/src/server.rs

@@ -201,14 +201,15 @@ impl SvcProcessor for DrdynvcServer {
                 let msg = c.processor.start(create_resp.channel_id())?;
                 resp.extend(encode_dvc_messages(id, msg, ChannelFlags::SHOW_PROTOCOL).map_err(|e| encode_err!(e))?);
             }
-            DrdynvcClientPdu::Close(close_resp) => {
-                debug!("Got DVC Close Response PDU: {close_resp:?}");
-                let c = self
-                    .channel_by_id(close_resp.channel_id())
-                    .map_err(|e| decode_err!(e))?;
+            DrdynvcClientPdu::Close(close) => {
+                debug!("Got DVC Close PDU: {close:?}");
+                let channel_id = close.channel_id();
+                let c = self.channel_by_id(channel_id).map_err(|e| decode_err!(e))?;
                 if c.state != ChannelState::Opened {
-                    return Err(pdu_other_err!("invalid channel state"));
+                    debug!(?channel_id, ?c.state, "Ignoring close for channel not in Opened state");
+                    return Ok(resp);
                 }
+                c.processor.close(channel_id);
                 c.state = ChannelState::Closed;
             }
             DrdynvcClientPdu::Data(data) => {