AdGuardHome/dhcpd/os_linux.go
2019-04-23 15:14:26 +03:00

46 lines
1.0 KiB
Go

package dhcpd
import (
"net"
"os"
"syscall"
"golang.org/x/net/ipv4"
)
// Create a socket for receiving broadcast packets
func newBroadcastPacketConn(bindAddr net.IP, port int, ifname string) (*ipv4.PacketConn, error) {
s, err := syscall.Socket(syscall.AF_INET, syscall.SOCK_DGRAM, syscall.IPPROTO_UDP)
if err != nil {
return nil, err
}
if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1); err != nil {
return nil, err
}
if err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1); err != nil {
return nil, err
}
if err := syscall.SetsockoptString(s, syscall.SOL_SOCKET, syscall.SO_BINDTODEVICE, ifname); err != nil {
return nil, err
}
addr := syscall.SockaddrInet4{Port: port}
copy(addr.Addr[:], bindAddr.To4())
err = syscall.Bind(s, &addr)
if err != nil {
syscall.Close(s)
return nil, err
}
f := os.NewFile(uintptr(s), "")
c, err := net.FilePacketConn(f)
f.Close()
if err != nil {
return nil, err
}
p := ipv4.NewPacketConn(c)
return p, nil
}