coredns/plugin/rewrite/reverter_test.go
Uwe Krueger 40edf1e566
plugin/rewrite: streamline the ResponseRule handling. (#4473)
* plugin/rewrite: streamline the ResponseRule handling.

The functionality of a response rule is now completely encapsulated behind
a `ResponseRule` interface. This significantly simplifies the complete
processing flow, it enables more flexible response handling and it is possible
to eliminate lots of state flags, ifs and switches.

Based on the new flexibility the pull request also enables to support a
response name rewrite for all name rewrite types.
To be compatible, an explicit `answer auto` option is added to support
a best effort response rewrite (name and value).
Additionally now all name rewrite rules support additional name and value
reponse rewrite options.

Using this feature it is also possible now to rewrite a complete sub domain
hierarchy to a single domain name combined with a correct rewrite (#2389).

Signed-off-by: Uwe Krueger <uwe.krueger@sap.com>

* revert policy

Signed-off-by: Uwe Krueger <uwe.krueger@sap.com>

Co-authored-by: Miek Gieben <miek@miek.nl>
2021-05-04 10:05:45 +02:00

179 lines
9.3 KiB
Go

package rewrite
import (
"context"
"testing"
"github.com/coredns/coredns/plugin"
"github.com/coredns/coredns/plugin/pkg/dnstest"
"github.com/coredns/coredns/plugin/test"
"github.com/miekg/dns"
)
var tests = []struct {
from string
fromType uint16
answer []dns.RR
to string
toType uint16
noRevert bool
}{
{"core.dns.rocks", dns.TypeA, []dns.RR{test.A("dns.core.rocks. 5 IN A 10.0.0.1")}, "core.dns.rocks", dns.TypeA, false},
{"core.dns.rocks", dns.TypeSRV, []dns.RR{test.SRV("dns.core.rocks. 5 IN SRV 0 100 100 srv1.dns.core.rocks.")}, "core.dns.rocks", dns.TypeSRV, false},
{"core.dns.rocks", dns.TypeA, []dns.RR{test.A("core.dns.rocks. 5 IN A 10.0.0.1")}, "dns.core.rocks.", dns.TypeA, true},
{"core.dns.rocks", dns.TypeSRV, []dns.RR{test.SRV("core.dns.rocks. 5 IN SRV 0 100 100 srv1.dns.core.rocks.")}, "dns.core.rocks.", dns.TypeSRV, true},
{"core.dns.rocks", dns.TypeHINFO, []dns.RR{test.HINFO("core.dns.rocks. 5 HINFO INTEL-64 \"RHEL 7.4\"")}, "core.dns.rocks", dns.TypeHINFO, false},
{"core.dns.rocks", dns.TypeA, []dns.RR{
test.A("dns.core.rocks. 5 IN A 10.0.0.1"),
test.A("dns.core.rocks. 5 IN A 10.0.0.2"),
}, "core.dns.rocks", dns.TypeA, false},
}
func TestResponseReverter(t *testing.T) {
rules := []Rule{}
r, _ := newNameRule("stop", "regex", `(core)\.(dns)\.(rocks)`, "{2}.{1}.{3}", "answer", "name", `(dns)\.(core)\.(rocks)`, "{2}.{1}.{3}")
rules = append(rules, r)
doReverterTests(rules, t)
rules = []Rule{}
r, _ = newNameRule("continue", "regex", `(core)\.(dns)\.(rocks)`, "{2}.{1}.{3}", "answer", "name", `(dns)\.(core)\.(rocks)`, "{2}.{1}.{3}")
rules = append(rules, r)
doReverterTests(rules, t)
}
func doReverterTests(rules []Rule, t *testing.T) {
ctx := context.TODO()
for i, tc := range tests {
m := new(dns.Msg)
m.SetQuestion(tc.from, tc.fromType)
m.Question[0].Qclass = dns.ClassINET
m.Answer = tc.answer
rw := Rewrite{
Next: plugin.HandlerFunc(msgPrinter),
Rules: rules,
RevertPolicy: NewRevertPolicy(tc.noRevert, false),
}
rec := dnstest.NewRecorder(&test.ResponseWriter{})
rw.ServeDNS(ctx, rec, m)
resp := rec.Msg
if resp.Question[0].Name != tc.to {
t.Errorf("Test %d: Expected Name to be %q but was %q", i, tc.to, resp.Question[0].Name)
}
if resp.Question[0].Qtype != tc.toType {
t.Errorf("Test %d: Expected Type to be '%d' but was '%d'", i, tc.toType, resp.Question[0].Qtype)
}
}
}
var valueTests = []struct {
from string
fromType uint16
answer []dns.RR
extra []dns.RR
to string
toType uint16
noRevert bool
expectValue string
expectAnswerType uint16
expectAddlName string
}{
{"my.domain.uk.", dns.TypeSRV, []dns.RR{test.SRV("my.cluster.local. 5 IN SRV 0 100 100 srv1.my.cluster.local.")}, []dns.RR{test.A("srv1.my.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeSRV, false, "srv1.my.domain.uk.", dns.TypeSRV, "srv1.my.domain.uk."},
{"my.domain.uk.", dns.TypeSRV, []dns.RR{test.SRV("my.cluster.local. 5 IN SRV 0 100 100 srv1.my.cluster.local.")}, []dns.RR{test.A("srv1.my.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeSRV, true, "srv1.my.cluster.local.", dns.TypeSRV, "srv1.my.cluster.local."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.CNAME("my.cluster.local. 3600 IN CNAME cname.cluster.local.")}, []dns.RR{test.A("cname.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeANY, false, "cname.domain.uk.", dns.TypeCNAME, "cname.domain.uk."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.CNAME("my.cluster.local. 3600 IN CNAME cname.cluster.local.")}, []dns.RR{test.A("cname.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeANY, true, "cname.cluster.local.", dns.TypeCNAME, "cname.cluster.local."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.DNAME("my.cluster.local. 3600 IN DNAME dname.cluster.local.")}, []dns.RR{test.A("dname.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeANY, false, "dname.domain.uk.", dns.TypeDNAME, "dname.domain.uk."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.DNAME("my.cluster.local. 3600 IN DNAME dname.cluster.local.")}, []dns.RR{test.A("dname.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeANY, true, "dname.cluster.local.", dns.TypeDNAME, "dname.cluster.local."},
{"my.domain.uk.", dns.TypeMX, []dns.RR{test.MX("my.cluster.local. 3600 IN MX 1 mx1.cluster.local.")}, []dns.RR{test.A("mx1.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeMX, false, "mx1.domain.uk.", dns.TypeMX, "mx1.domain.uk."},
{"my.domain.uk.", dns.TypeMX, []dns.RR{test.MX("my.cluster.local. 3600 IN MX 1 mx1.cluster.local.")}, []dns.RR{test.A("mx1.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeMX, true, "mx1.cluster.local.", dns.TypeMX, "mx1.cluster.local."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.NS("my.cluster.local. 3600 IN NS ns1.cluster.local.")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeANY, false, "ns1.domain.uk.", dns.TypeNS, "ns1.domain.uk."},
{"my.domain.uk.", dns.TypeANY, []dns.RR{test.NS("my.cluster.local. 3600 IN NS ns1.cluster.local.")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeANY, true, "ns1.cluster.local.", dns.TypeNS, "ns1.cluster.local."},
{"my.domain.uk.", dns.TypeSOA, []dns.RR{test.SOA("my.cluster.local. 1800 IN SOA ns1.cluster.local. admin.cluster.local. 1502165581 14400 3600 604800 14400")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeSOA, false, "ns1.domain.uk.", dns.TypeSOA, "ns1.domain.uk."},
{"my.domain.uk.", dns.TypeSOA, []dns.RR{test.SOA("my.cluster.local. 1800 IN SOA ns1.cluster.local. admin.cluster.local. 1502165581 14400 3600 604800 14400")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeSOA, true, "ns1.cluster.local.", dns.TypeSOA, "ns1.cluster.local."},
{"my.domain.uk.", dns.TypeNAPTR, []dns.RR{test.NAPTR("my.cluster.local. 100 IN NAPTR 100 10 \"S\" \"SIP+D2U\" \"!^.*$!sip:customer-service@example.com!\" _sip._udp.cluster.local.")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.domain.uk.", dns.TypeNAPTR, false, "_sip._udp.domain.uk.", dns.TypeNAPTR, "ns1.domain.uk."},
{"my.domain.uk.", dns.TypeNAPTR, []dns.RR{test.NAPTR("my.cluster.local. 100 IN NAPTR 100 10 \"S\" \"SIP+D2U\" \"!^.*$!sip:customer-service@example.com!\" _sip._udp.cluster.local.")}, []dns.RR{test.A("ns1.cluster.local. 5 IN A 10.0.0.1")}, "my.cluster.local.", dns.TypeNAPTR, true, "_sip._udp.cluster.local.", dns.TypeNAPTR, "ns1.cluster.local."},
}
func TestValueResponseReverter(t *testing.T) {
rules := []Rule{}
r, err := newNameRule("stop", "regex", `(.*)\.domain\.uk`, "{1}.cluster.local", "answer", "name", `(.*)\.cluster\.local`, "{1}.domain.uk", "answer", "value", `(.*)\.cluster\.local`, "{1}.domain.uk")
if err != nil {
t.Errorf("cannot parse rule: %s", err)
return
}
rules = append(rules, r)
doValueReverterTests("stop", rules, t)
rules = []Rule{}
r, err = newNameRule("continue", "regex", `(.*)\.domain\.uk`, "{1}.cluster.local", "answer", "name", `(.*)\.cluster\.local`, "{1}.domain.uk", "answer", "value", `(.*)\.cluster\.local`, "{1}.domain.uk")
if err != nil {
t.Errorf("cannot parse rule: %s", err)
return
}
rules = append(rules, r)
doValueReverterTests("continue", rules, t)
rules = []Rule{}
r, err = newNameRule("stop", "suffix", `.domain.uk`, ".cluster.local", "answer", "auto", "answer", "value", `(.*)\.cluster\.local`, "{1}.domain.uk")
if err != nil {
t.Errorf("cannot parse rule: %s", err)
return
}
rules = append(rules, r)
doValueReverterTests("suffix", rules, t)
}
func doValueReverterTests(name string, rules []Rule, t *testing.T) {
ctx := context.TODO()
for i, tc := range valueTests {
m := new(dns.Msg)
m.SetQuestion(tc.from, tc.fromType)
m.Question[0].Qclass = dns.ClassINET
m.Answer = tc.answer
m.Extra = tc.extra
rw := Rewrite{
Next: plugin.HandlerFunc(msgPrinter),
Rules: rules,
RevertPolicy: NewRevertPolicy(tc.noRevert, false),
}
rec := dnstest.NewRecorder(&test.ResponseWriter{})
rw.ServeDNS(ctx, rec, m)
resp := rec.Msg
if resp.Question[0].Name != tc.to {
t.Errorf("Test %s.%d: Expected Name to be %q but was %q", name, i, tc.to, resp.Question[0].Name)
}
if resp.Question[0].Qtype != tc.toType {
t.Errorf("Test %s.%d: Expected Type to be '%d' but was '%d'", name, i, tc.toType, resp.Question[0].Qtype)
}
if len(resp.Answer) <= 0 {
t.Errorf("Test %s.%d: No Answers", name, i)
return
}
if len(resp.Answer) > 0 && resp.Answer[0].Header().Rrtype != tc.expectAnswerType {
t.Errorf("Test %s.%d: Unexpected Answer Record Type %d", name, i, resp.Answer[0].Header().Rrtype)
return
}
value := getRecordValueForRewrite(resp.Answer[0])
if value != tc.expectValue {
t.Errorf("Test %s.%d: Expected Target to be '%s' but was '%s'", name, i, tc.expectValue, value)
}
if len(resp.Extra) <= 0 || resp.Extra[0].Header().Rrtype != dns.TypeA {
t.Errorf("Test %s.%d: Unexpected Additional Record Type / No Additional Records", name, i)
return
}
if resp.Extra[0].Header().Name != tc.expectAddlName {
t.Errorf("Test %s.%d: Expected Extra Name to be %q but was %q", name, i, tc.expectAddlName, resp.Extra[0].Header().Name)
}
}
}