Xray-core/features/dns/localdns/client.go

64 lines
1.4 KiB
Go

package localdns
import (
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/features/dns"
)
// Client is an implementation of dns.Client, which queries localhost for DNS.
type Client struct{}
// Type implements common.HasType.
func (*Client) Type() interface{} {
return dns.ClientType()
}
// Start implements common.Runnable.
func (*Client) Start() error { return nil }
// Close implements common.Closable.
func (*Client) Close() error { return nil }
// LookupIP implements Client.
func (*Client) LookupIP(host string, option dns.IPOption) ([]net.IP, error) {
ips, err := net.LookupIP(host)
if err != nil {
return nil, err
}
parsedIPs := make([]net.IP, 0, len(ips))
ipv4 := make([]net.IP, 0, len(ips))
ipv6 := make([]net.IP, 0, len(ips))
for _, ip := range ips {
parsed := net.IPAddress(ip)
if parsed != nil {
parsedIPs = append(parsedIPs, parsed.IP())
}
if len(ip) == net.IPv4len {
ipv4 = append(ipv4, ip)
}
if len(ip) == net.IPv6len {
ipv6 = append(ipv6, ip)
}
}
switch {
case option.IPv4Enable && option.IPv6Enable:
if len(parsedIPs) > 0 {
return parsedIPs, nil
}
case option.IPv4Enable:
if len(ipv4) > 0 {
return ipv4, nil
}
case option.IPv6Enable:
if len(ipv6) > 0 {
return ipv6, nil
}
}
return nil, dns.ErrEmptyResponse
}
// New create a new dns.Client that queries localhost for DNS.
func New() *Client {
return &Client{}
}