Fix error handling and cleanup of netlink listener

This commit is contained in:
Jason A. Donenfeld 2018-04-27 02:23:48 +02:00
parent 0715bdf353
commit 92261b770f

View file

@ -36,31 +36,15 @@ type NativeTun struct {
closingWriter *os.File
}
func toRTMGRP(sc uint) uint {
return 1 << (sc - 1)
}
func (tun *NativeTun) bindRTMGRP() (int, error) {
groups := toRTMGRP(unix.RTNLGRP_LINK)
groups |= toRTMGRP(unix.RTNLGRP_IPV4_IFADDR)
groups |= toRTMGRP(unix.RTNLGRP_IPV6_IFADDR)
sock, err := unix.Socket(unix.AF_NETLINK, unix.SOCK_RAW, unix.NETLINK_ROUTE)
if err != nil {
return 0, err
}
saddr := &unix.SockaddrNetlink{
Family: unix.AF_NETLINK,
Pid: uint32(os.Getpid()),
Groups: uint32(groups),
}
return sock, unix.Bind(sock, saddr)
}
func (tun *NativeTun) File() *os.File {
return tun.fd
}
func (tun *NativeTun) RoutineHackListener() {
// TODO: This function never actually exits in response to anything,
// a go routine that goes forever. We'll want to fix that if this is
// to ever be used as any sort of library.
/* This is needed for the detection to work across network namespaces
* If you are reading this and know a better method, please get in touch.
*/
@ -78,12 +62,35 @@ func (tun *NativeTun) RoutineHackListener() {
}
}
func toRTMGRP(sc uint) uint {
return 1 << (sc - 1)
}
func (tun *NativeTun) RoutineNetlinkListener() {
sock, err := tun.bindRTMGRP()
groups := toRTMGRP(unix.RTNLGRP_LINK)
groups |= toRTMGRP(unix.RTNLGRP_IPV4_IFADDR)
groups |= toRTMGRP(unix.RTNLGRP_IPV6_IFADDR)
sock, err := unix.Socket(unix.AF_NETLINK, unix.SOCK_RAW, unix.NETLINK_ROUTE)
if err != nil {
tun.errors <- errors.New("Failed to create netlink event listener")
tun.errors <- errors.New("Failed to create netlink event listener socket")
return
}
defer unix.Close(sock)
saddr := &unix.SockaddrNetlink{
Family: unix.AF_NETLINK,
Pid: uint32(os.Getpid()),
Groups: uint32(groups),
}
err = unix.Bind(sock, saddr)
if err != nil {
tun.errors <- errors.New("Failed to bind netlink event listener socket")
return
}
// TODO: This function never actually exits in response to anything,
// a go routine that goes forever. We'll want to fix that if this is
// to ever be used as any sort of library.
for msg := make([]byte, 1<<16); ; {