tailscale/net/netns/netns_darwin_tailscaled.go
Brad Fitzpatrick 713c5c9ab1 net/{interfaces,netns}: change which build tag means mac/ios Network/System Extension
We used to use "redo" for that, but it was pretty vague.

Also, fix the build tags broken in interfaces_default_route_test.go from
a9745a0b68, moving those Linux-specific
tests to interfaces_linux_test.go.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2021-06-03 08:29:22 -07:00

53 lines
1.4 KiB
Go

// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build darwin,!ts_macext
package netns
import (
"fmt"
"log"
"strings"
"syscall"
"golang.org/x/sys/unix"
"tailscale.com/net/interfaces"
)
// control marks c as necessary to dial in a separate network namespace.
//
// It's intentionally the same signature as net.Dialer.Control
// and net.ListenConfig.Control.
func control(network, address string, c syscall.RawConn) error {
if strings.HasPrefix(address, "127.") || address == "::1" {
// Don't bind to an interface for localhost connections.
return nil
}
idx, err := interfaces.DefaultRouteInterfaceIndex()
if err != nil {
log.Printf("netns: DefaultRouteInterfaceIndex: %v", err)
return nil
}
v6 := strings.Contains(address, "]:") || strings.HasSuffix(network, "6") // hacky test for v6
proto := unix.IPPROTO_IP
opt := unix.IP_BOUND_IF
if v6 {
proto = unix.IPPROTO_IPV6
opt = unix.IPV6_BOUND_IF
}
var sockErr error
err = c.Control(func(fd uintptr) {
sockErr = unix.SetsockoptInt(int(fd), proto, opt, idx)
})
if err != nil {
return fmt.Errorf("RawConn.Control on %T: %w", c, err)
}
if sockErr != nil {
log.Printf("netns: control(%q, %q), v6=%v, index=%v: %v", network, address, v6, idx, sockErr)
}
return sockErr
}