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Merge pull request #38 from miekg/etcd-stub

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Etcd stub
This commit is contained in:
Miek Gieben
2016-03-24 09:23:44 +00:00
parent 163e5d8e71 78d2e31ec1
commit b45208e3e5
6 changed files with 380 additions and 241 deletions
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2
middleware/etcd/etcd.go
View File

@@ -17,7 +17,7 @@ import (
type Etcd struct {
Next middleware.Handler
Zones []string
Proxy proxy.Proxy
Proxy proxy.Proxy // Proxy for looking up names during the resolution process
Client etcdc.KeysAPI
Ctx context.Context
Inflight *singleflight.Group

3
middleware/etcd/etcd.md
View File

@@ -4,6 +4,9 @@
a [message](https://github.com/skynetservices/skydns/blob/2fcff74cdc9f9a7dd64189a447ef27ac354b725f/msg/service.go#L26)
like [SkyDNS](https//github.com/skynetservices/skydns).
The etcd middleware makes extensive use of the proxy middleware to forward and query
other servers in the network.
## Syntax
~~~

2
middleware/etcd/lookup.go
View File

@@ -28,7 +28,6 @@ func (e Etcd) A(zone string, state middleware.State, previousRecords []dns.RR) (
// x CNAME x is a direct loop, don't add those
continue
}
println("TRYING TO ADD CNAME", len(previousRecords))
newRecord := serv.NewCNAME(state.QName(), serv.Host)
if len(previousRecords) > 7 {
@@ -54,7 +53,6 @@ func (e Etcd) A(zone string, state middleware.State, previousRecords []dns.RR) (
target := newRecord.Target
if dns.IsSubDomain(zone, target) {
// We should already have found it
println("DIDN'T FOUND IT")
continue
}
m1, e1 := e.Proxy.Lookup(state, target, state.QType())

260
middleware/etcd/lookup_test.go
View File

@@ -7,128 +7,10 @@ package etcd
// names.
import (
"encoding/json"
"sort"
"testing"
"time"
"github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/etcd/msg"
"github.com/miekg/coredns/middleware/etcd/singleflight"
"github.com/miekg/coredns/middleware/proxy"
"github.com/miekg/dns"
etcdc "github.com/coreos/etcd/client"
"golang.org/x/net/context"
)
var (
etc Etcd
client etcdc.KeysAPI
ctx context.Context
)
type Section int
const (
Answer Section = iota
Ns
Extra
)
func init() {
ctx = context.TODO()
etcdCfg := etcdc.Config{
Endpoints: []string{"http://localhost:2379"},
}
cli, _ := etcdc.New(etcdCfg)
etc = Etcd{
Proxy: proxy.New([]string{"8.8.8.8:53"}),
PathPrefix: "skydns",
Ctx: context.Background(),
Inflight: &singleflight.Group{},
Zones: []string{"skydns.test."},
Client: etcdc.NewKeysAPI(cli),
}
}
func set(t *testing.T, e Etcd, k string, ttl time.Duration, m *msg.Service) {
b, err := json.Marshal(m)
if err != nil {
t.Fatal(err)
}
path, _ := e.PathWithWildcard(k)
e.Client.Set(ctx, path, string(b), &etcdc.SetOptions{TTL: ttl})
}
func delete(t *testing.T, e Etcd, k string) {
path, _ := e.PathWithWildcard(k)
e.Client.Delete(ctx, path, &etcdc.DeleteOptions{Recursive: false})
}
type rrSet []dns.RR
func (p rrSet) Len() int { return len(p) }
func (p rrSet) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
func (p rrSet) Less(i, j int) bool { return p[i].String() < p[j].String() }
func TestLookup(t *testing.T) {
for _, serv := range services {
set(t, etc, serv.Key, 0, serv)
defer delete(t, etc, serv.Key)
}
for _, tc := range dnsTestCases {
m := new(dns.Msg)
m.SetQuestion(dns.Fqdn(tc.Qname), tc.Qtype)
rec := middleware.NewResponseRecorder(&middleware.TestResponseWriter{})
_, err := etc.ServeDNS(ctx, rec, m)
if err != nil {
t.Errorf("expected no error, got %v\n", err)
return
}
resp := rec.Reply()
sort.Sort(rrSet(resp.Answer))
sort.Sort(rrSet(resp.Ns))
sort.Sort(rrSet(resp.Extra))
t.Logf("%v\n", resp)
if resp.Rcode != tc.Rcode {
t.Errorf("rcode is %q, expected %q", dns.RcodeToString[resp.Rcode], dns.RcodeToString[tc.Rcode])
continue
}
if len(resp.Answer) != len(tc.Answer) {
t.Errorf("answer for %q contained %d results, %d expected", tc.Qname, len(resp.Answer), len(tc.Answer))
continue
}
if len(resp.Ns) != len(tc.Ns) {
t.Errorf("authority for %q contained %d results, %d expected", tc.Qname, len(resp.Ns), len(tc.Ns))
continue
}
if len(resp.Extra) != len(tc.Extra) {
t.Errorf("additional for %q contained %d results, %d expected", tc.Qname, len(resp.Extra), len(tc.Extra))
continue
}
checkSection(t, tc, Answer, resp.Answer)
checkSection(t, tc, Ns, resp.Ns)
checkSection(t, tc, Extra, resp.Extra)
}
}
type dnsTestCase struct {
Qname string
Qtype uint16
Rcode int
Answer []dns.RR
Ns []dns.RR
Extra []dns.RR
}
// Note the key is encoded as DNS name, while in "reality" it is a etcd path.
var services = []*msg.Service{
{Host: "server1", Port: 8080, Key: "a.server1.dev.region1.skydns.test."},
@@ -136,12 +18,18 @@ var services = []*msg.Service{
{Host: "10.0.0.2", Port: 8080, Key: "b.server1.prod.region1.skydns.test."},
{Host: "::1", Port: 8080, Key: "b.server6.prod.region1.skydns.test."},
// CNAME dedup Test
// CNAME dedup
{Host: "www.miek.nl", Key: "a.miek.nl.skydns.test."},
{Host: "www.miek.nl", Key: "b.miek.nl.skydns.test."},
// Unresolvable internal name
{Host: "unresolvable.skydns.test", Key: "cname.prod.region1.skydns.test."},
// priority
{Host: "server1", Priority: 333, Port: 8080, Key: "priority.skydns.test."},
// Subdomain
{Host: "server1", Port: 0, Key: "a.sub.region1.skydns.test."},
{Host: "server2", Port: 80, Key: "b.sub.region1.skydns.test."},
{Host: "10.0.0.1", Port: 8080, Key: "c.sub.region1.skydns.test."},
}
var dnsTestCases = []dnsTestCase{
@@ -182,6 +70,21 @@ var dnsTestCases = []dnsTestCase{
newA("server1.prod.region1.skydns.test. 300 A 10.0.0.2"),
},
},
// Priority Test
{
Qname: "priority.skydns.test.", Qtype: dns.TypeSRV,
Answer: []dns.RR{newSRV("priority.skydns.test. 300 SRV 333 100 8080 server1.")},
},
// Subdomain Test
{
Qname: "sub.region1.skydns.test.", Qtype: dns.TypeSRV,
Answer: []dns.RR{
newSRV("sub.region1.skydns.test. 300 IN SRV 10 33 0 server1."),
newSRV("sub.region1.skydns.test. 300 IN SRV 10 33 80 server2."),
newSRV("sub.region1.skydns.test. 300 IN SRV 10 33 8080 c.sub.region1.skydns.test."),
},
Extra: []dns.RR{newA("c.sub.region1.skydns.test. 300 IN A 10.0.0.1")},
},
// Multi SRV with the same target, should be dedupped.
{
Qname: "*.miek.nl.skydns.test.", Qtype: dns.TypeSRV,
@@ -223,29 +126,6 @@ var dnsTestCases = []dnsTestCase{
Answer: []dns.RR{},
Ns: []dns.RR{newSOA("skydns.test. 60 SOA ns.dns.skydns.test. hostmaster.skydns.test. 1407441600 28800 7200 604800 60")},
},
// Priority Test
{
Qname: "region6.skydns.test.", Qtype: dns.TypeSRV,
Answer: []dns.RR{newSRV("region6.skydns.test. 300 SRV 333 100 80 server4.")},
},
// Subdomain Test
{
Qname: "region1.skydns.test.", Qtype: dns.TypeSRV,
Answer: []dns.RR{
newSRV("region1.skydns.test. 300 SRV 10 33 0 104.server1.dev.region1.skydns.test."),
newSRV("region1.skydns.test. 300 SRV 10 33 80 server2"),
newSRV("region1.skydns.test. 300 SRV 10 33 8080 server1.")},
Extra: []dns.RR{newA("104.server1.dev.region1.skydns.test. 300 A 10.0.0.1")},
},
// Subdomain Weight Test
{
Qname: "region5.skydns.test.", Qtype: dns.TypeSRV,
Answer: []dns.RR{
newSRV("region5.skydns.test. 300 SRV 10 22 0 server2."),
newSRV("region5.skydns.test. 300 SRV 10 36 0 server1."),
newSRV("region5.skydns.test. 300 SRV 10 41 0 server3."),
newSRV("region5.skydns.test. 300 SRV 30 100 0 server4.")},
},
// Wildcard Test
{
Qname: "*.region1.skydns.test.", Qtype: dns.TypeSRV,
@@ -299,99 +179,3 @@ var dnsTestCases = []dnsTestCase{
},
*/
}
func newA(rr string) *dns.A { r, _ := dns.NewRR(rr); return r.(*dns.A) }
func newAAAA(rr string) *dns.AAAA { r, _ := dns.NewRR(rr); return r.(*dns.AAAA) }
func newCNAME(rr string) *dns.CNAME { r, _ := dns.NewRR(rr); return r.(*dns.CNAME) }
func newSRV(rr string) *dns.SRV { r, _ := dns.NewRR(rr); return r.(*dns.SRV) }
func newSOA(rr string) *dns.SOA { r, _ := dns.NewRR(rr); return r.(*dns.SOA) }
func newNS(rr string) *dns.NS { r, _ := dns.NewRR(rr); return r.(*dns.NS) }
func newPTR(rr string) *dns.PTR { r, _ := dns.NewRR(rr); return r.(*dns.PTR) }
func newTXT(rr string) *dns.TXT { r, _ := dns.NewRR(rr); return r.(*dns.TXT) }
func newMX(rr string) *dns.MX { r, _ := dns.NewRR(rr); return r.(*dns.MX) }
func checkSection(t *testing.T, tc dnsTestCase, sect Section, rr []dns.RR) {
section := []dns.RR{}
switch sect {
case 0:
section = tc.Answer
case 1:
section = tc.Ns
case 2:
section = tc.Extra
}
for i, a := range rr {
if a.Header().Name != section[i].Header().Name {
t.Errorf("answer %d should have a Header Name of %q, but has %q", i, section[i].Header().Name, a.Header().Name)
continue
}
// 303 signals: don't care what the ttl is.
if section[i].Header().Ttl != 303 && a.Header().Ttl != section[i].Header().Ttl {
t.Errorf("Answer %d should have a Header TTL of %d, but has %d", i, section[i].Header().Ttl, a.Header().Ttl)
continue
}
if a.Header().Rrtype != section[i].Header().Rrtype {
t.Errorf("answer %d should have a header rr type of %d, but has %d", i, section[i].Header().Rrtype, a.Header().Rrtype)
continue
}
switch x := a.(type) {
case *dns.SRV:
if x.Priority != section[i].(*dns.SRV).Priority {
t.Errorf("answer %d should have a Priority of %d, but has %d", i, section[i].(*dns.SRV).Priority, x.Priority)
}
if x.Weight != section[i].(*dns.SRV).Weight {
t.Errorf("answer %d should have a Weight of %d, but has %d", i, section[i].(*dns.SRV).Weight, x.Weight)
}
if x.Port != section[i].(*dns.SRV).Port {
t.Errorf("answer %d should have a Port of %d, but has %d", i, section[i].(*dns.SRV).Port, x.Port)
}
if x.Target != section[i].(*dns.SRV).Target {
t.Errorf("answer %d should have a Target of %q, but has %q", i, section[i].(*dns.SRV).Target, x.Target)
}
case *dns.A:
if x.A.String() != section[i].(*dns.A).A.String() {
t.Errorf("answer %d should have a Address of %q, but has %q", i, section[i].(*dns.A).A.String(), x.A.String())
}
case *dns.AAAA:
if x.AAAA.String() != section[i].(*dns.AAAA).AAAA.String() {
t.Errorf("answer %d should have a Address of %q, but has %q", i, section[i].(*dns.AAAA).AAAA.String(), x.AAAA.String())
}
case *dns.TXT:
for j, txt := range x.Txt {
if txt != section[i].(*dns.TXT).Txt[j] {
t.Errorf("answer %d should have a Txt of %q, but has %q", i, section[i].(*dns.TXT).Txt[j], txt)
}
}
case *dns.SOA:
tt := section[i].(*dns.SOA)
if x.Ns != tt.Ns {
t.Errorf("SOA nameserver should be %q, but is %q", x.Ns, tt.Ns)
}
case *dns.PTR:
tt := section[i].(*dns.PTR)
if x.Ptr != tt.Ptr {
t.Errorf("PTR ptr should be %q, but is %q", x.Ptr, tt.Ptr)
}
case *dns.CNAME:
tt := section[i].(*dns.CNAME)
if x.Target != tt.Target {
t.Errorf("CNAME target should be %q, but is %q", x.Target, tt.Target)
}
case *dns.MX:
tt := section[i].(*dns.MX)
if x.Mx != tt.Mx {
t.Errorf("MX Mx should be %q, but is %q", x.Mx, tt.Mx)
}
if x.Preference != tt.Preference {
t.Errorf("MX Preference should be %q, but is %q", x.Preference, tt.Preference)
}
case *dns.NS:
tt := section[i].(*dns.NS)
if x.Ns != tt.Ns {
t.Errorf("NS nameserver should be %q, but is %q", x.Ns, tt.Ns)
}
}
}
}

247
middleware/etcd/setup_test.go Normal file
View File

@@ -0,0 +1,247 @@
package etcd
// etcd needs to be running on http://127.0.0.1:2379
// *and* needs connectivity to the internet for remotely resolving
// names.
import (
"encoding/json"
"sort"
"testing"
"time"
"github.com/miekg/coredns/middleware"
"github.com/miekg/coredns/middleware/etcd/msg"
"github.com/miekg/coredns/middleware/etcd/singleflight"
"github.com/miekg/coredns/middleware/proxy"
"github.com/miekg/dns"
etcdc "github.com/coreos/etcd/client"
"golang.org/x/net/context"
)
var (
etc Etcd
client etcdc.KeysAPI
ctx context.Context
)
type Section int
const (
Answer Section = iota
Ns
Extra
)
func init() {
ctx = context.TODO()
etcdCfg := etcdc.Config{
Endpoints: []string{"http://localhost:2379"},
}
cli, _ := etcdc.New(etcdCfg)
etc = Etcd{
Proxy: proxy.New([]string{"8.8.8.8:53"}),
PathPrefix: "skydns",
Ctx: context.Background(),
Inflight: &singleflight.Group{},
Zones: []string{"skydns.test."},
Client: etcdc.NewKeysAPI(cli),
}
}
func set(t *testing.T, e Etcd, k string, ttl time.Duration, m *msg.Service) {
b, err := json.Marshal(m)
if err != nil {
t.Fatal(err)
}
path, _ := e.PathWithWildcard(k)
e.Client.Set(ctx, path, string(b), &etcdc.SetOptions{TTL: ttl})
}
func delete(t *testing.T, e Etcd, k string) {
path, _ := e.PathWithWildcard(k)
e.Client.Delete(ctx, path, &etcdc.DeleteOptions{Recursive: false})
}
type rrSet []dns.RR
func (p rrSet) Len() int { return len(p) }
func (p rrSet) Swap(i, j int) { p[i], p[j] = p[j], p[i] }
func (p rrSet) Less(i, j int) bool { return p[i].String() < p[j].String() }
func TestLookup(t *testing.T) {
for _, serv := range services {
set(t, etc, serv.Key, 0, serv)
defer delete(t, etc, serv.Key)
}
for _, tc := range dnsTestCases {
m := new(dns.Msg)
m.SetQuestion(dns.Fqdn(tc.Qname), tc.Qtype)
rec := middleware.NewResponseRecorder(&middleware.TestResponseWriter{})
_, err := etc.ServeDNS(ctx, rec, m)
if err != nil {
t.Errorf("expected no error, got %v\n", err)
return
}
resp := rec.Reply()
sort.Sort(rrSet(resp.Answer))
sort.Sort(rrSet(resp.Ns))
sort.Sort(rrSet(resp.Extra))
if resp.Rcode != tc.Rcode {
t.Errorf("rcode is %q, expected %q", dns.RcodeToString[resp.Rcode], dns.RcodeToString[tc.Rcode])
t.Logf("%v\n", resp)
continue
}
if len(resp.Answer) != len(tc.Answer) {
t.Errorf("answer for %q contained %d results, %d expected", tc.Qname, len(resp.Answer), len(tc.Answer))
t.Logf("%v\n", resp)
continue
}
if len(resp.Ns) != len(tc.Ns) {
t.Errorf("authority for %q contained %d results, %d expected", tc.Qname, len(resp.Ns), len(tc.Ns))
t.Logf("%v\n", resp)
continue
}
if len(resp.Extra) != len(tc.Extra) {
t.Errorf("additional for %q contained %d results, %d expected", tc.Qname, len(resp.Extra), len(tc.Extra))
t.Logf("%v\n", resp)
continue
}
if !checkSection(t, tc, Answer, resp.Answer) {
t.Logf("%v\n", resp)
}
if !checkSection(t, tc, Ns, resp.Ns) {
t.Logf("%v\n", resp)
}
if !checkSection(t, tc, Extra, resp.Extra) {
t.Logf("%v\n", resp)
}
}
}
type dnsTestCase struct {
Qname string
Qtype uint16
Rcode int
Answer []dns.RR
Ns []dns.RR
Extra []dns.RR
}
func newA(rr string) *dns.A { r, _ := dns.NewRR(rr); return r.(*dns.A) }
func newAAAA(rr string) *dns.AAAA { r, _ := dns.NewRR(rr); return r.(*dns.AAAA) }
func newCNAME(rr string) *dns.CNAME { r, _ := dns.NewRR(rr); return r.(*dns.CNAME) }
func newSRV(rr string) *dns.SRV { r, _ := dns.NewRR(rr); return r.(*dns.SRV) }
func newSOA(rr string) *dns.SOA { r, _ := dns.NewRR(rr); return r.(*dns.SOA) }
func newNS(rr string) *dns.NS { r, _ := dns.NewRR(rr); return r.(*dns.NS) }
func newPTR(rr string) *dns.PTR { r, _ := dns.NewRR(rr); return r.(*dns.PTR) }
func newTXT(rr string) *dns.TXT { r, _ := dns.NewRR(rr); return r.(*dns.TXT) }
func newMX(rr string) *dns.MX { r, _ := dns.NewRR(rr); return r.(*dns.MX) }
func checkSection(t *testing.T, tc dnsTestCase, sect Section, rr []dns.RR) bool {
section := []dns.RR{}
switch sect {
case 0:
section = tc.Answer
case 1:
section = tc.Ns
case 2:
section = tc.Extra
}
for i, a := range rr {
if a.Header().Name != section[i].Header().Name {
t.Errorf("answer %d should have a Header Name of %q, but has %q", i, section[i].Header().Name, a.Header().Name)
return false
}
// 303 signals: don't care what the ttl is.
if section[i].Header().Ttl != 303 && a.Header().Ttl != section[i].Header().Ttl {
t.Errorf("Answer %d should have a Header TTL of %d, but has %d", i, section[i].Header().Ttl, a.Header().Ttl)
return false
}
if a.Header().Rrtype != section[i].Header().Rrtype {
t.Errorf("answer %d should have a header rr type of %d, but has %d", i, section[i].Header().Rrtype, a.Header().Rrtype)
return false
}
switch x := a.(type) {
case *dns.SRV:
if x.Priority != section[i].(*dns.SRV).Priority {
t.Errorf("answer %d should have a Priority of %d, but has %d", i, section[i].(*dns.SRV).Priority, x.Priority)
return false
}
if x.Weight != section[i].(*dns.SRV).Weight {
t.Errorf("answer %d should have a Weight of %d, but has %d", i, section[i].(*dns.SRV).Weight, x.Weight)
return false
}
if x.Port != section[i].(*dns.SRV).Port {
t.Errorf("answer %d should have a Port of %d, but has %d", i, section[i].(*dns.SRV).Port, x.Port)
return false
}
if x.Target != section[i].(*dns.SRV).Target {
t.Errorf("answer %d should have a Target of %q, but has %q", i, section[i].(*dns.SRV).Target, x.Target)
return false
}
case *dns.A:
if x.A.String() != section[i].(*dns.A).A.String() {
t.Errorf("answer %d should have a Address of %q, but has %q", i, section[i].(*dns.A).A.String(), x.A.String())
return false
}
case *dns.AAAA:
if x.AAAA.String() != section[i].(*dns.AAAA).AAAA.String() {
t.Errorf("answer %d should have a Address of %q, but has %q", i, section[i].(*dns.AAAA).AAAA.String(), x.AAAA.String())
return false
}
case *dns.TXT:
for j, txt := range x.Txt {
if txt != section[i].(*dns.TXT).Txt[j] {
t.Errorf("answer %d should have a Txt of %q, but has %q", i, section[i].(*dns.TXT).Txt[j], txt)
return false
}
}
case *dns.SOA:
tt := section[i].(*dns.SOA)
if x.Ns != tt.Ns {
t.Errorf("SOA nameserver should be %q, but is %q", x.Ns, tt.Ns)
return false
}
case *dns.PTR:
tt := section[i].(*dns.PTR)
if x.Ptr != tt.Ptr {
t.Errorf("PTR ptr should be %q, but is %q", x.Ptr, tt.Ptr)
return false
}
case *dns.CNAME:
tt := section[i].(*dns.CNAME)
if x.Target != tt.Target {
t.Errorf("CNAME target should be %q, but is %q", x.Target, tt.Target)
return false
}
case *dns.MX:
tt := section[i].(*dns.MX)
if x.Mx != tt.Mx {
t.Errorf("MX Mx should be %q, but is %q", x.Mx, tt.Mx)
return false
}
if x.Preference != tt.Preference {
t.Errorf("MX Preference should be %q, but is %q", x.Preference, tt.Preference)
return false
}
case *dns.NS:
tt := section[i].(*dns.NS)
if x.Ns != tt.Ns {
t.Errorf("NS nameserver should be %q, but is %q", x.Ns, tt.Ns)
return false
}
}
}
return true
}

107
middleware/etcd/stub.go Normal file
View File

@@ -0,0 +1,107 @@
package etcd
import (
"net"
"strconv"
"strings"
"github.com/miekg/dns"
)
// hasStubEdns0 checks if the message is carrying our special
// edns0 zero option.
func hasStubEdns0(m *dns.Msg) bool {
option := m.IsEdns0()
if option == nil {
return false
}
for _, o := range option.Option {
if o.Option() == ednsStubCode && len(o.(*dns.EDNS0_LOCAL).Data) == 1 &&
o.(*dns.EDNS0_LOCAL).Data[0] == 1 {
return true
}
}
return false
}
// addStubEdns0 adds our special option to the message's OPT record.
func addStubEdns0(m *dns.Msg) *dns.Msg {
option := m.IsEdns0()
// Add a custom EDNS0 option to the packet, so we can detect loops
// when 2 stubs are forwarding to each other.
if option != nil {
option.Option = append(option.Option, &dns.EDNS0_LOCAL{ednsStubCode, []byte{1}})
} else {
m.Extra = append(m.Extra, ednsStub)
}
return m
}
// Look in .../dns/stub/<domain>/xx for msg.Services. Loop through them
// extract <domain> and add them as forwarders (ip:port-combos) for
// the stub zones. Only numeric (i.e. IP address) hosts are used.
// TODO(miek): makes this Startup Function.
func (e Etcd) UpdateStubZones(zone string) error {
stubmap := make(map[string][]string)
services, err := e.Records("stub.dns."+zone, false)
if err != nil {
return err
}
for _, serv := range services {
if serv.Port == 0 {
serv.Port = 53
}
ip := net.ParseIP(serv.Host)
if ip == nil {
//logf("stub zone non-address %s seen for: %s", serv.Key, serv.Host)
continue
}
domain := e.Domain(serv.Key)
labels := dns.SplitDomainName(domain)
// If the remaining name equals any of the zones we have, we ignore it.
for _, z := range e.Zones {
// Chop of left most label, because that is used as the nameserver place holder
// and drop the right most labels that belong to zone.
domain = dns.Fqdn(strings.Join(labels[1:len(labels)-dns.CountLabel(z)], "."))
if domain == z {
continue
}
stubmap[domain] = append(stubmap[domain], net.JoinHostPort(serv.Host, strconv.Itoa(serv.Port)))
}
}
// TODO(miek): add to etcd structure and startup with a StartFunction
// e.stub = &stubmap
// stubmap contains proxy is best way forward... I think.
// TODO(miek): setup a proxy that forward to these
// StubProxy type?
return nil
}
func ServeDNSStubForward(w dns.ResponseWriter, req *dns.Msg) *dns.Msg {
if !hasStubEdns0(req) {
return nil
}
req = addStubEdns0(req)
// proxy woxy
return nil
}
// ednsStub is the EDNS0 record we add to stub queries. Queries which have this record are
// not forwarded again.
var ednsStub = func() *dns.OPT {
o := new(dns.OPT)
o.Hdr.Name = "."
o.Hdr.Rrtype = dns.TypeOPT
e := new(dns.EDNS0_LOCAL)
e.Code = ednsStubCode
e.Data = []byte{1}
o.Option = append(o.Option, e)
return o
}()
const ednsStubCode = dns.EDNS0LOCALSTART + 10