feat(dgw): dynamically load XMF native lib on startup (#939)

devolutions-gateway/Cargo.toml

@@ -83,10 +83,13 @@ utoipa = { version = "4.2", default-features = false, features = ["uuid", "time"
 # Safe pin projection
 pin-project-lite = "0.2"
 
-# Native plugins
+# Native plugins (QUESTION: now that we have Cadeau integrated, should we remove this feature?)
 dlopen = "0.1"
 dlopen_derive = "0.1"
 
+# Video processing for session recording
+cadeau = { version = "0.3", features = ["dlopen"] }
+
 # Dependencies required for PCAP support (QUESTION: should we keep that built-in?)
 pcap-file = "2.0"
 etherparse = "0.15"

devolutions-gateway/src/config.rs

@@ -1080,6 +1080,9 @@ pub mod dto {
         /// Providing this option will cause the PCAP interceptor to be attached to each stream.
         pub capture_path: Option<Utf8PathBuf>,
 
+        /// Path to the XMF shared library (Cadeau) for runtime loading.
+        pub lib_xmf_path: Option<Utf8PathBuf>,
+
         /// Enable unstable API which may break at any point
         #[serde(default)]
         pub enable_unstable: bool,
@@ -1095,6 +1098,7 @@ pub mod dto {
                 override_kdc: None,
                 log_directives: None,
                 capture_path: None,
+                lib_xmf_path: None,
                 enable_unstable: false,
             }
         }

devolutions-gateway/src/service.rs

@@ -1,4 +1,5 @@
 use anyhow::Context as _;
+use camino::Utf8PathBuf;
 use devolutions_gateway::config::{Conf, ConfHandle};
 use devolutions_gateway::listener::GatewayListener;
 use devolutions_gateway::log::GatewayLog;
@@ -70,6 +71,38 @@ impl GatewayService {
             warn!("Anomality detected with TLS configuration: {e:#}");
         }
 
+        let xmf_lib_path;
+        let xmf_lib_path = if let Some(path) = conf.debug.lib_xmf_path.as_deref() {
+            Some(path)
+        } else if cfg!(target_os = "windows") {
+            if let Ok(mut exe_path) = std::env::current_exe() {
+                exe_path.pop();
+                exe_path.push("xmf.dll");
+                xmf_lib_path = Utf8PathBuf::from_path_buf(exe_path).ok();
+                xmf_lib_path.as_deref()
+            } else {
+                None
+            }
+        } else if cfg!(target_os = "linux") {
+            xmf_lib_path = Some(Utf8PathBuf::from("/usr/lib/libxmf.so"));
+            xmf_lib_path.as_deref()
+        } else {
+            None
+        };
+
+        if let Some(path) = xmf_lib_path {
+            // SAFETY: No initialisation or termination routine in the XMF library we should worry about for preconditions.
+            let result = unsafe { cadeau::xmf::init(path.as_str()) };
+
+            match result {
+                Ok(_) => info!("XMF native library loaded and installed"),
+                Err(error) => warn!(
+                    %error,
+                    "Failed to load XMF native library, video processing features are disabled"
+                ),
+            }
+        }
+
         Ok(GatewayService {
             conf_handle,
             state: GatewayState::Stopped,