From 9fbc5b3f950760e2b776c3545fb61575b3832c56 Mon Sep 17 00:00:00 2001
From: Packet Please <pktpls@systemli.org>
Date: Fri, 20 Sep 2024 01:28:09 +0200
Subject: [PATCH] tunspace: more robust uplink handling, and direct interface
 support

---
 packages/tunspace/tunspace.defaults |  1 +
 packages/tunspace/tunspace.uc       | 48 ++++++++++++++++-------------
 2 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/packages/tunspace/tunspace.defaults b/packages/tunspace/tunspace.defaults
index 758ada12..f65211be 100644
--- a/packages/tunspace/tunspace.defaults
+++ b/packages/tunspace/tunspace.defaults
@@ -7,6 +7,7 @@ package 'tunspace'
 config tunspace "tunspace"
   option uplink_netns "uplink"
   option uplink_ifname "br-wan"
+  option uplink_mode "bridge"
   option maintenance_interval 15
   option debug 0
 
diff --git a/packages/tunspace/tunspace.uc b/packages/tunspace/tunspace.uc
index 40fa336f..479e92a6 100644
--- a/packages/tunspace/tunspace.uc
+++ b/packages/tunspace/tunspace.uc
@@ -40,6 +40,7 @@ function load_config(name) {
     "debug": int(ts.debug) != 0,
     "uplink_netns": ""+ts.uplink_netns,
     "uplink_ifname": ""+ts.uplink_ifname,
+    "uplink_mode": ""+ts.uplink_mode,
     "maintenance_interval": int(ts.maintenance_interval),
     "wireguard_servers": {},
     "wireguard_interfaces": {},
@@ -393,32 +394,37 @@ function wireguard_maintenance(st, cfg) {
 }
 
 // TODO: ts_uplink interface leaks into default namespace when uplink namespace is deleted
-function uplink_maintenance(nsid, netns, ifname) {
+function uplink_maintenance(nsid, netns, ifname, mode) {
   let netnsifname = UPLINK_NETNS_IFNAME;
 
+  if (interface_exists(netnsifname)) {
+    // the uplink interface will sometimes leak out of the namespace on shutdown
+    shell_command("ip link set "+netnsifname+" netns "+netns);
+  }
+
   if (interface_exists_netns(netnsifname, netns)) {
-    // try dhcp for 5 seconds
-    shell_command("ip netns exec "+netns+" udhcpc -f -n -q -A 5 -i "+netnsifname+" -s /usr/share/tunspace/udhcpc.script 2>&1 | grep 'ip addr add'");
+    shell_command("ip -n "+netns+" link set "+netnsifname+" up");
+  } else if (!interface_exists(ifname)) {
+    log(sprintf("missing uplink interface %s", ifname));
+    return false;
+  } else if (mode == "direct") {
+    // move uplink interface directly:
+    shell_command("ip link set dev "+ifname+" netns "+netns);
+    shell_command("ip -n "+netns+" link set "+ifname+" name "+netnsifname);
+    shell_command("ip -n "+netns+" link set "+netnsifname+" up");
+  } else if (mode == "bridge") {
+    // or create a macvlan bridge:
+    shell_command("ip link add "+netnsifname+" link "+ifname+" type macvlan mode bridge");
+    shell_command("ip link set dev "+netnsifname+" netns "+netns);
+    shell_command("ip -n "+netns+" link set up "+netnsifname+"");
   } else {
-    if (!interface_exists(ifname)) {
-      log(sprintf("missing uplink interface %s", ifname));
-      return false;
-    } else {
-      // move uplink interface directly:
-      // shell_command("ip link set dev "+ifname+" netns "+netns);
-      // shell_command("ip -n "+netns+" link set "+ifname+" up");
-      // shell_command("ip -n "+netns+" link set "+ifname+" name "+netnsifname);
-
-      // or create a macvlan bridge:
-      shell_command("ip link add "+netnsifname+" link "+ifname+" type macvlan mode bridge");
-      shell_command("ip link set dev "+netnsifname+" netns "+netns);
-      shell_command("ip -n "+netns+" link set up "+netnsifname+"");
-
-      // try dhcp for 5 seconds
-      shell_command("ip netns exec "+netns+" udhcpc -f -n -q -A 5 -i "+netnsifname+" -s /usr/share/tunspace/udhcpc.script 2>&1 | grep 'ip addr add'");
-    }
+    log(sprintf("uplink mode must be 'bridge' or 'direct', got '%s'", mode));
+    return false;
   }
 
+  // try dhcp for 5 seconds
+  shell_command("ip netns exec "+netns+" udhcpc -f -n -q -A 5 -i "+netnsifname+" -s /usr/share/tunspace/udhcpc.script 2>&1 | grep 'ip addr add'");
+
   return true;
 }
 
@@ -444,7 +450,7 @@ function boot(st, cfg) {
 function tick(st, cfg) {
   debug("tick");
 
-  if (!uplink_maintenance(st.nsid, cfg.uplink_netns, cfg.uplink_ifname)) {
+  if (!uplink_maintenance(st.nsid, cfg.uplink_netns, cfg.uplink_ifname, cfg.uplink_mode)) {
     log("uplink maintenance failed");
   }
   wireguard_maintenance(st, cfg);