fix(cliprdr): allow servers to announce clipboard ownership (#1053)

Servers can now send Format List PDU via initiate_copy() regardless of
internal state. The existing state machine was designed for clients
where clipboard initialization must complete before announcing
ownership.

MS-RDPECLIP Section 2.2.3.1 specifies that Format List PDU is sent by
either client or server when the local clipboard is updated. Servers
should be able to announce clipboard changes immediately after channel
negotiation.

This change enables RDP servers to properly announce clipboard ownership
by bypassing the Initialization/Ready state check when R::is_server() is
true. Client behavior remains unchanged.

Co-authored-by: lamco-office <office@lamco.io>

Author: glamberson

crates/ironrdp-cliprdr/src/lib.rs

@@ -230,26 +230,32 @@ impl<R: Role> Cliprdr<R> {
     pub fn initiate_copy(&self, available_formats: &[ClipboardFormat]) -> PduResult<CliprdrSvcMessages<R>> {
         let mut pdus = Vec::new();
 
-        match (self.state, R::is_server()) {
-            // When user initiates copy, we should send format list to server.
-            (CliprdrState::Ready, _) => {
-                pdus.push(ClipboardPdu::FormatList(
-                    self.build_format_list(available_formats).map_err(|e| encode_err!(e))?,
-                ));
-            }
-            (CliprdrState::Initialization, false) => {
-                // During initialization state, first copy action is synthetic and should be sent along with
-                // capabilities and temporary directory PDUs.
-                pdus.push(ClipboardPdu::Capabilities(self.capabilities.clone()));
-                pdus.push(ClipboardPdu::TemporaryDirectory(
-                    ClientTemporaryDirectory::new(self.backend.temporary_directory()).map_err(|e| encode_err!(e))?,
-                ));
-                pdus.push(ClipboardPdu::FormatList(
-                    self.build_format_list(available_formats).map_err(|e| encode_err!(e))?,
-                ));
-            }
-            _ => {
-                error!(?self.state, "Attempted to initiate copy in incorrect state");
+        if R::is_server() {
+            pdus.push(ClipboardPdu::FormatList(
+                self.build_format_list(available_formats).map_err(|e| encode_err!(e))?,
+            ));
+        } else {
+            match self.state {
+                CliprdrState::Ready => {
+                    pdus.push(ClipboardPdu::FormatList(
+                        self.build_format_list(available_formats).map_err(|e| encode_err!(e))?,
+                    ));
+                }
+                CliprdrState::Initialization => {
+                    // During initialization state, first copy action is synthetic and should be sent along with
+                    // capabilities and temporary directory PDUs.
+                    pdus.push(ClipboardPdu::Capabilities(self.capabilities.clone()));
+                    pdus.push(ClipboardPdu::TemporaryDirectory(
+                        ClientTemporaryDirectory::new(self.backend.temporary_directory())
+                            .map_err(|e| encode_err!(e))?,
+                    ));
+                    pdus.push(ClipboardPdu::FormatList(
+                        self.build_format_list(available_formats).map_err(|e| encode_err!(e))?,
+                    ));
+                }
+                _ => {
+                    error!(?self.state, "Attempted to initiate copy in incorrect state");
+                }
             }
         }