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|
//go:build darwin || dragonfly || freebsd || netbsd || openbsd
package gateway
import (
"net"
"os/exec"
"syscall"
"golang.org/x/net/route"
)
func readNetstat() ([]byte, error) {
routeCmd := exec.Command("netstat", "-rn")
return routeCmd.CombinedOutput()
}
func discoverGatewayOSSpecific() (ip net.IP, err error) {
rib, err := route.FetchRIB(syscall.AF_INET, syscall.NET_RT_DUMP, 0)
if err != nil {
return nil, err
}
msgs, err := route.ParseRIB(syscall.NET_RT_DUMP, rib)
if err != nil {
return nil, err
}
for _, m := range msgs {
switch m := m.(type) {
case *route.RouteMessage:
var ip net.IP
switch sa := m.Addrs[syscall.RTAX_GATEWAY].(type) {
case *route.Inet4Addr:
ip = net.IPv4(sa.IP[0], sa.IP[1], sa.IP[2], sa.IP[3])
return ip, nil
case *route.Inet6Addr:
ip = make(net.IP, net.IPv6len)
copy(ip, sa.IP[:])
return ip, nil
}
}
}
return nil, &ErrNoGateway{}
}
func discoverGatewayInterfaceOSSpecific() (ip net.IP, err error) {
bytes, err := readNetstat()
if err != nil {
return nil, err
}
return parseUnixInterfaceIP(bytes)
}
|
