Files
coredns/middleware/whoami/whoami.go
Miek Gieben c4ab98c6e3 Add middleware.NextOrFailure (#462)
This checks if the next middleware to be called is nil, and if so returns
ServerFailure and an error. This makes the next calling more robust and
saves some lines of code.

Also prefix the error with the name of the middleware to aid in
debugging.
2016-12-20 18:58:05 +00:00

58 lines
1.4 KiB
Go

// Package whoami implements a middleware that returns details about the resolving
// querying it.
package whoami
import (
"net"
"strconv"
"github.com/miekg/coredns/request"
"github.com/miekg/dns"
"golang.org/x/net/context"
)
// Whoami is a middleware that returns your IP address, port and the protocol used for connecting
// to CoreDNS.
type Whoami struct{}
// ServeDNS implements the middleware.Handler interface.
func (wh Whoami) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
state := request.Request{W: w, Req: r}
a := new(dns.Msg)
a.SetReply(r)
a.Compress = true
a.Authoritative = true
ip := state.IP()
var rr dns.RR
switch state.Family() {
case 1:
rr = new(dns.A)
rr.(*dns.A).Hdr = dns.RR_Header{Name: state.QName(), Rrtype: dns.TypeA, Class: state.QClass()}
rr.(*dns.A).A = net.ParseIP(ip).To4()
case 2:
rr = new(dns.AAAA)
rr.(*dns.AAAA).Hdr = dns.RR_Header{Name: state.QName(), Rrtype: dns.TypeAAAA, Class: state.QClass()}
rr.(*dns.AAAA).AAAA = net.ParseIP(ip)
}
srv := new(dns.SRV)
srv.Hdr = dns.RR_Header{Name: "_" + state.Proto() + "." + state.QName(), Rrtype: dns.TypeSRV, Class: state.QClass()}
port, _ := strconv.Atoi(state.Port())
srv.Port = uint16(port)
srv.Target = "."
a.Extra = []dns.RR{rr, srv}
state.SizeAndDo(a)
w.WriteMsg(a)
return 0, nil
}
// Name implements the Handler interface.
func (wh Whoami) Name() string { return "whoami" }