From 4ddd0d2ffc7073f2d55ffb6777e3a168af0051f0 Mon Sep 17 00:00:00 2001 From: James O'Doherty Date: Fri, 29 May 2026 20:11:07 -0400 Subject: Refactor rootless namespace joining to use C launcher Fix an architectural shortfall where concurrent sessions failed to share the target network and mount namespaces. Because the Go runtime is multi-threaded, calling unix.Setns with CLONE_NEWNS from Go always returned EINVAL, silently forcing concurrent runs to fall back to bootstrapping separate isolated namespaces and separate WireGuard connections. This commit resolves the issue by extending the embedded single-threaded C launcher to handle namespace joining, and introducing a host-to-isolated path propagation pattern: 1. Launcher setns Support: The C launcher now checks for WG_WRAP_JOIN_PID in the environment. If present, it joins the User, Mount, and Network namespaces of the active PID in single-threaded mode before executing the Go binary. 2. BootstrapJoin Integration: Implemented namespace.BootstrapJoin to transition joining sessions via the launcher. 3. Path Preservation: Export WG_WRAP_HOST_RUNTIME_BASE_DIR from the host to ensure the isolated instance maps the profile and PID directories to the exact same location. 4. Redundant Tunnel Bypass: Detect joined sessions via WG_WRAP_JOINED=1 in the CLI and bypass starting a duplicate WireGuard tunnel on the occupied tun0. 5. Testing: Added tests/e2e/sharing_test.go to assert namespace ID equality, which now passes successfully. 6. Git Tracking: Fixed .gitignore overmatch to stop ignoring cmd/wg-wrap/. --- internal/paths/paths.go | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'internal/paths/paths.go') diff --git a/internal/paths/paths.go b/internal/paths/paths.go index f512ad1..c7bdd94 100644 --- a/internal/paths/paths.go +++ b/internal/paths/paths.go @@ -44,6 +44,10 @@ func (pm *PathManager) RuntimeBaseDir() string { return pm.RuntimeBaseOverride } + if envDir := os.Getenv("WG_WRAP_HOST_RUNTIME_BASE_DIR"); envDir != "" { + return envDir + } + if envDir := os.Getenv("XDG_RUNTIME_DIR"); envDir != "" { return envDir } -- cgit v1.2.3