func ipToSocksAddr(family int, ip net.IP, port int, zone string) (unix.Sockaddr, error) {
switch family {
case unix.AF_INET:
if len(ip) == 0 {
ip = net.IPv4zero
}
if ip = ip.To4(); ip == nil {
return nil, net.InvalidAddrError("non-IPv4 address")
}
sa := new(unix.SockaddrInet4)
for i := 0; i < net.IPv4len; i++ {
sa.Addr[i] = ip[i]
}
sa.Port = port
return sa, nil
case unix.AF_INET6:
if len(ip) == 0 {
ip = net.IPv6zero
}
// IPv4 callers use 0.0.0.0 to mean "announce on any available address".
// In IPv6 mode, Linux treats that as meaning "announce on 0.0.0.0",
// which it refuses to do. Rewrite to the IPv6 unspecified address.
if ip.Equal(net.IPv4zero) {
ip = net.IPv6zero
}
if ip = ip.To16(); ip == nil {
return nil, net.InvalidAddrError("non-IPv6 address")
}
sa := new(unix.SockaddrInet6)
for i := 0; i < net.IPv6len; i++ {
sa.Addr[i] = ip[i]
}
sa.Port = port
sa.ZoneId = uint32(zoneToInt(zone))
return sa, nil
}
return nil, net.InvalidAddrError("unexpected socket family")
}
