coredns/test/cache_test.go
Miek Gieben 35b40a84f2
plugin/cache: Fix filtering (#4148)
The filtering of DNSSEC records in the cache plugin was not done
correctly. Also the change to introduced this bug didn't take into
account that the cache - by virtue of differentiating between DNSSEC and
no-DNSSEC - relied on not copying the data from the cache.

This change copies and then filters the data and factors the filtering
into a function that is used in two places (albeit with on ugly boolean
parameters to prevent copying things twice).

Add tests, do_test.go is moved to test/cache_test.go because the OPT
handing is done outside of the cache plugin. The core server re-attaches
the correct OPT when replying, so that makes for a better e2e test.

Added small unit test for filterRRslice and an explicit test that asks
for DNSSEC first and then plain, and vice versa to test cache behavior.

Fixes: #4146

Signed-off-by: Miek Gieben <miek@miek.nl>
2020-09-28 07:53:00 -07:00

112 lines
2.6 KiB
Go

package test
import (
"testing"
"github.com/coredns/coredns/plugin/test"
"github.com/miekg/dns"
)
func TestLookupCache(t *testing.T) {
// Start auth. CoreDNS holding the auth zone.
name, rm, err := test.TempFile(".", exampleOrg)
if err != nil {
t.Fatalf("Failed to create zone: %s", err)
}
defer rm()
corefile := `example.org:0 {
file ` + name + `
}`
i, udp, _, err := CoreDNSServerAndPorts(corefile)
if err != nil {
t.Fatalf("Could not get CoreDNS serving instance: %s", err)
}
defer i.Stop()
// Start caching forward CoreDNS that we want to test.
corefile = `example.org:0 {
forward . ` + udp + `
cache 10
}`
i, udp, _, err = CoreDNSServerAndPorts(corefile)
if err != nil {
t.Fatalf("Could not get CoreDNS serving instance: %s", err)
}
defer i.Stop()
t.Run("Long TTL", func(t *testing.T) {
testCase(t, "example.org.", udp, 2, 10)
})
t.Run("Short TTL", func(t *testing.T) {
testCase(t, "short.example.org.", udp, 1, 5)
})
t.Run("DNSSEC OPT", func(t *testing.T) {
testCaseDNSSEC(t, "example.org.", udp, 4096)
})
t.Run("DNSSEC OPT", func(t *testing.T) {
testCaseDNSSEC(t, "example.org.", udp, 0)
})
}
func testCase(t *testing.T, name, addr string, expectAnsLen int, expectTTL uint32) {
m := new(dns.Msg)
m.SetQuestion(name, dns.TypeA)
resp, err := dns.Exchange(m, addr)
if err != nil {
t.Fatalf("Expected to receive reply, but didn't: %s", err)
}
if len(resp.Answer) != expectAnsLen {
t.Fatalf("Expected %v RR in the answer section, got %v.", expectAnsLen, len(resp.Answer))
}
ttl := resp.Answer[0].Header().Ttl
if ttl != expectTTL {
t.Errorf("Expected TTL to be %d, got %d", expectTTL, ttl)
}
}
func testCaseDNSSEC(t *testing.T, name, addr string, bufsize int) {
m := new(dns.Msg)
m.SetQuestion(name, dns.TypeA)
if bufsize > 0 {
o := &dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}}
o.SetDo()
o.SetUDPSize(uint16(bufsize))
m.Extra = append(m.Extra, o)
}
resp, err := dns.Exchange(m, addr)
if err != nil {
t.Fatalf("Expected to receive reply, but didn't: %s", err)
}
if len(resp.Extra) == 0 && bufsize == 0 {
// no OPT, this is OK
return
}
opt := resp.Extra[len(resp.Extra)-1]
if x, ok := opt.(*dns.OPT); !ok && bufsize > 0 {
t.Fatalf("Expected OPT RR, got %T", x)
}
if bufsize > 0 {
if !opt.(*dns.OPT).Do() {
t.Errorf("Expected DO bit to be set, got false")
}
if x := opt.(*dns.OPT).UDPSize(); int(x) != bufsize {
t.Errorf("Expected %d bufsize, got %d", bufsize, x)
}
} else {
if opt.Header().Rrtype == dns.TypeOPT {
t.Errorf("Expected no OPT RR, but got one: %s", opt)
}
}
}