1 files changed, 0 insertions, 106 deletions
diff --git a/middleware/proxy/dns.go b/middleware/proxy/dns.go
deleted file mode 100644
index 4d8038422..000000000
--- a/middleware/proxy/dns.go
+++ /dev/null
@@ -1,106 +0,0 @@
-package proxy
-
-import (
-	"context"
-	"net"
-	"time"
-
-	"github.com/coredns/coredns/request"
-
-	"github.com/miekg/dns"
-)
-
-type dnsEx struct {
-	Timeout time.Duration
-	Options
-}
-
-// Options define the options understood by dns.Exchange.
-type Options struct {
-	ForceTCP bool // If true use TCP for upstream no matter what
-}
-
-func newDNSEx() *dnsEx {
-	return newDNSExWithOption(Options{})
-}
-
-func newDNSExWithOption(opt Options) *dnsEx {
-	return &dnsEx{Timeout: defaultTimeout * time.Second, Options: opt}
-}
-
-func (d *dnsEx) Transport() string {
-	if d.Options.ForceTCP {
-		return "tcp"
-	}
-
-	// The protocol will be determined by `state.Proto()` during Exchange.
-	return ""
-}
-func (d *dnsEx) Protocol() string          { return "dns" }
-func (d *dnsEx) OnShutdown(p *Proxy) error { return nil }
-func (d *dnsEx) OnStartup(p *Proxy) error  { return nil }
-
-// Exchange implements the Exchanger interface.
-func (d *dnsEx) Exchange(ctx context.Context, addr string, state request.Request) (*dns.Msg, error) {
-	proto := state.Proto()
-	if d.Options.ForceTCP {
-		proto = "tcp"
-	}
-	co, err := net.DialTimeout(proto, addr, d.Timeout)
-	if err != nil {
-		return nil, err
-	}
-
-	reply, _, err := d.ExchangeConn(state.Req, co)
-
-	co.Close()
-
-	if reply != nil && reply.Truncated {
-		// Suppress proxy error for truncated responses
-		err = nil
-	}
-
-	if err != nil {
-		return nil, err
-	}
-	// Make sure it fits in the DNS response.
-	reply, _ = state.Scrub(reply)
-	reply.Compress = true
-	reply.Id = state.Req.Id
-
-	return reply, nil
-}
-
-func (d *dnsEx) ExchangeConn(m *dns.Msg, co net.Conn) (*dns.Msg, time.Duration, error) {
-	start := time.Now()
-	r, err := exchange(m, co)
-	rtt := time.Since(start)
-
-	return r, rtt, err
-}
-
-func exchange(m *dns.Msg, co net.Conn) (*dns.Msg, error) {
-	opt := m.IsEdns0()
-
-	udpsize := uint16(dns.MinMsgSize)
-	// If EDNS0 is used use that for size.
-	if opt != nil && opt.UDPSize() >= dns.MinMsgSize {
-		udpsize = opt.UDPSize()
-	}
-
-	dnsco := &dns.Conn{Conn: co, UDPSize: udpsize}
-
-	writeDeadline := time.Now().Add(defaultTimeout)
-	dnsco.SetWriteDeadline(writeDeadline)
-	dnsco.WriteMsg(m)
-
-	readDeadline := time.Now().Add(defaultTimeout)
-	co.SetReadDeadline(readDeadline)
-	r, err := dnsco.ReadMsg()
-
-	dnsco.Close()
-	if r == nil {
-		return nil, err
-	}
-	return r, err
-}