Added back glue records in NS response, expanded unit test. Also reused same function used in node lookup for adding A/AAAA records in the extra section of the NS response

This commit is contained in:
Preetha Appan 2017-08-04 16:53:42 -05:00 committed by Frank Schroeder
parent c7c4100503
commit 52075bda1c
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GPG Key ID: 4D65C6EAEC87DECD
2 changed files with 26 additions and 21 deletions

View File

@ -212,7 +212,7 @@ func (d *DNSServer) handleQuery(resp dns.ResponseWriter, req *dns.Msg) {
switch req.Question[0].Qtype {
case dns.TypeSOA:
ns, glue := d.nameservers()
ns, glue := d.nameservers(req.IsEdns0() != nil)
m.Answer = append(m.Answer, d.soa())
m.Ns = append(m.Ns, ns...)
m.Extra = append(m.Extra, glue...)
@ -236,9 +236,9 @@ func (d *DNSServer) handleQuery(resp dns.ResponseWriter, req *dns.Msg) {
m.SetRcode(req, dns.RcodeSuccess)
case dns.TypeNS:
ns, _ := d.nameservers()
ns, glue := d.nameservers(req.IsEdns0() != nil)
m.Answer = ns
// no need to send A records with the IP address, since the ns record is a node name that resolves correctly
m.Extra = glue
m.SetRcode(req, dns.RcodeSuccess)
default:
@ -283,7 +283,7 @@ func (d *DNSServer) addSOA(msg *dns.Msg) {
// nameservers returns the names and ip addresses of up to three random servers
// in the current cluster which serve as authoritative name servers for zone.
func (d *DNSServer) nameservers() (ns []dns.RR, extra []dns.RR) {
func (d *DNSServer) nameservers(edns bool) (ns []dns.RR, extra []dns.RR) {
// get server names and store them in a map to randomize the output
servers := map[string]net.IP{}
for name, addr := range d.agent.delegate.ServerAddrs() {
@ -324,18 +324,8 @@ func (d *DNSServer) nameservers() (ns []dns.RR, extra []dns.RR) {
Ns: name,
}
ns = append(ns, nsrr)
// the glue record providing the ip address
a := &dns.A{
Hdr: dns.RR_Header{
Name: name,
Rrtype: dns.TypeA,
Class: dns.ClassINET,
Ttl: uint32(d.config.NodeTTL / time.Second),
},
A: ip,
}
extra = append(extra, a)
extra = append(extra, d.formatNodeRecord(ip.String(), name, dns.TypeANY, d.config.NodeTTL, edns)...)
// don't provide more than 3 servers
if len(ns) >= 3 {
@ -523,7 +513,7 @@ RPC:
n := out.NodeServices.Node
edns := req.IsEdns0() != nil
addr := d.agent.TranslateAddress(datacenter, n.Address, n.TaggedAddresses)
records := d.formatNodeRecord(out.NodeServices.Node, addr,
records := d.formatNodeRecord(addr,
req.Question[0].Name, qType, d.config.NodeTTL, edns)
if records != nil {
resp.Answer = append(resp.Answer, records...)
@ -531,7 +521,7 @@ RPC:
}
// formatNodeRecord takes a Node and returns an A, AAAA, or CNAME record
func (d *DNSServer) formatNodeRecord(node *structs.Node, addr, qName string, qType uint16, ttl time.Duration, edns bool) (records []dns.RR) {
func (d *DNSServer) formatNodeRecord(addr, qName string, qType uint16, ttl time.Duration, edns bool) (records []dns.RR) {
// Parse the IP
ip := net.ParseIP(addr)
var ipv4 net.IP
@ -911,7 +901,7 @@ func (d *DNSServer) serviceNodeRecords(dc string, nodes structs.CheckServiceNode
handled[addr] = struct{}{}
// Add the node record
records := d.formatNodeRecord(node.Node, addr, qName, qType, ttl, edns)
records := d.formatNodeRecord(addr, qName, qType, ttl, edns)
if records != nil {
resp.Answer = append(resp.Answer, records...)
}
@ -955,7 +945,7 @@ func (d *DNSServer) serviceSRVRecords(dc string, nodes structs.CheckServiceNodes
}
// Add the extra record
records := d.formatNodeRecord(node.Node, addr, srvRec.Target, dns.TypeANY, ttl, edns)
records := d.formatNodeRecord(addr, srvRec.Target, dns.TypeANY, ttl, edns)
if len(records) > 0 {
// Use the node address if it doesn't differ from the service address
if addr == node.Node.Address {

View File

@ -885,7 +885,7 @@ func TestDNS_NSRecords(t *testing.T) {
t.Parallel()
cfg := TestConfig()
cfg.Domain = "CONSUL."
cfg.NodeName = "foo"
cfg.NodeName = "server1"
a := NewTestAgent(t.Name(), cfg)
defer a.Shutdown()
@ -922,13 +922,28 @@ func TestDNS_NSRecords(t *testing.T) {
if !ok {
t.Fatalf("Bad: %#v", in.Answer[0])
}
if nsRec.Ns != "foo.node.dc1.consul." {
if nsRec.Ns != "server1.node.dc1.consul." {
t.Fatalf("Bad: %#v", in.Answer[0])
}
if nsRec.Hdr.Ttl != 0 {
t.Fatalf("Bad: %#v", in.Answer[0])
}
if len(in.Extra) != 1 {
t.Fatalf("Bad: %#v", in.Extra)
}
aRec, ok := in.Extra[0].(*dns.A)
if !ok {
t.Fatalf("Bad: %#v", in.Extra)
}
if aRec.A.String() != "127.0.0.1" {
t.Fatalf("Bad: %#v", in.Extra)
}
if aRec.Hdr.Name != "server1.node.dc1.consul." {
t.Fatalf("Bad: %#v", in.Extra)
}
}
func TestDNS_ExternalServiceToConsulCNAMENestedLookup(t *testing.T) {