feat(vmm): add forward_service_enabled config for bridge-mode port forwarding

Author: kvinwang

vmm/src/app.rs

@@ -356,7 +356,7 @@ impl App {
                 .networking
                 .as_ref()
                 .unwrap_or(&self.config.cvm.networking);
-            if !networking.is_bridge() {
+            if !networking.is_bridge() || !networking.forward_service_enabled {
                 return;
             }
             let guest_ip = vm.state.guest_ip.clone();

vmm/src/config.rs

@@ -384,6 +384,9 @@ pub struct Networking {
     #[serde(default)]
     pub bridge: String,
 
+    /// Enable userspace port forwarding for bridge-mode VMs.
+    pub forward_service_enabled: bool,
+
     // ── MAC prefix ─────────────────────────────────────────────────
     /// Fixed MAC address prefix (0-3 colon-separated hex bytes, e.g. "02:ab:cd").
     /// Remaining bytes are derived from the VM ID hash.

vmm/src/main_service.rs

@@ -229,6 +229,7 @@ fn networking_from_proto(proto: &rpc::NetworkingConfig) -> Option<crate::config:
         no_map_gw: false,
         ipv4_only: false,
         netdev: String::new(),
+        forward_service_enabled: false,
     })
 }
 

vmm/vmm.toml

@@ -99,6 +99,7 @@ ipv4_only = true
 
 # for mode = "bridge"
 # bridge = "virbr0"
+forward_service_enabled = false
 
 [cvm.port_mapping]
 enabled = false