middleware/secondary: multiple fixes (#745)

Fix transferring the zone from a master and the matching of notifies
to source and dst IP addresses.

Add `upstream` keyword as well, because it is needed for the same
reasons as in the *file* middlware.
Add some dire warning about upstream in the readme of both middlewares.

Out of band testing, hidden by net build tag was added. Integration
testing still needs to be setup.

1 files changed, 126 insertions, 0 deletions

diff --git a/test/secondary_net_test.go b/test/secondary_net_test.go
new file mode 100644
index 000000000..451195442
--- /dev/null
+++ b/test/secondary_net_test.go
@@ -0,0 +1,126 @@
+// +build net
+
+package test
+
+import (
+	"testing"
+
+	"github.com/miekg/dns"
+)
+
+func TestSecondaryZoneTransfer(t *testing.T) {
+	/*
+		Test will only work when there is a CoreDNS running on part 32054
+		with example.com and willing to transfer
+		coredns -conf Corefile -dns.port 32054
+		Corefile:
+			example.com {
+			    file example.com {
+				transfer to 127.0.0.1:32053
+			    }
+			}
+		example.com:
+			example.com.		3600	IN	SOA	sns.dns.icann.org. noc.dns.icann.org. 2017042730 7200 3600 1209600 3600
+
+			example.com.		65118	IN	NS	a.iana-servers.net.
+			example.com.		65118	IN	NS	b.iana-servers.net.
+			cname.example.com.       434334  IN      CNAME   a.miek.nl.
+	*/
+
+	corefile := `example.com:32053 {
+		secondary {
+			transfer from 127.0.0.1:32054
+		}
+	}
+	`
+
+	sec, err := CoreDNSServer(corefile)
+	if err != nil {
+		t.Fatalf("Could not get CoreDNS serving instance: %s", err)
+	}
+
+	defer sec.Stop()
+
+	m := new(dns.Msg)
+	m.SetQuestion("cname.example.com.", dns.TypeCNAME)
+
+	r, err := dns.Exchange(m, "127.0.0.1:32053")
+	if err != nil {
+		t.Fatalf("Expected to receive reply, but didn't: %s", err)
+	}
+
+	if len(r.Answer) == 0 {
+		t.Fatalf("Expected answer section")
+	}
+
+	if r.Answer[0].(*dns.CNAME).Target != "a.miek.nl." {
+		t.Fatalf("Expected target of %s, got %s", "a.miek.nl.", r.Answer[0].(*dns.CNAME).Target)
+	}
+
+	m = new(dns.Msg)
+	m.SetQuestion("example.com.", dns.TypeSOA)
+	r, err = dns.Exchange(m, "127.0.0.1:32053")
+	if err != nil {
+		t.Fatalf("Expected to receive reply, but didn't: %s", err)
+	}
+	if len(r.Answer) == 0 {
+		t.Fatalf("Expected answer section")
+	}
+	if r.Answer[0].(*dns.SOA).Serial != 2017042730 {
+		t.Fatalf("Expected serial of %d, got %d", 2017042730, r.Answer[0].(*dns.SOA).Serial)
+	}
+}
+
+func TestSecondaryZoneTransferUpstream(t *testing.T) {
+	/*
+		Test will only work when there is a CoreDNS running on part 32054
+		with example.com and willing to transfer
+		coredns -conf Corefile -dns.port 32054
+		Corefile:
+			example.com {
+			    file example.com {
+				transfer to 127.0.0.1:32053
+			    }
+			}
+		example.com:
+			example.com.		3600	IN	SOA	sns.dns.icann.org. noc.dns.icann.org. 2017042730 7200 3600 1209600 3600
+
+			example.com.		65118	IN	NS	a.iana-servers.net.
+			example.com.		65118	IN	NS	b.iana-servers.net.
+			cname.example.com.       434334  IN      CNAME   a.miek.nl.
+	*/
+
+	corefile := `example.com:32053 {
+		secondary {
+			transfer from 127.0.0.1:32054
+			upstream 8.8.8.8
+		}
+	}
+	`
+
+	sec, err := CoreDNSServer(corefile)
+	if err != nil {
+		t.Fatalf("Could not get CoreDNS serving instance: %s", err)
+	}
+
+	defer sec.Stop()
+
+	m := new(dns.Msg)
+	m.SetQuestion("cname.example.com.", dns.TypeA)
+
+	r, err := dns.Exchange(m, "127.0.0.1:32053")
+	if err != nil {
+		t.Fatalf("Expected to receive reply, but didn't: %s", err)
+	}
+
+	if len(r.Answer) != 2 {
+		t.Fatalf("Expected answer section, with 2 records, got %d", len(r.Answer))
+	}
+
+	if r.Answer[0].(*dns.CNAME).Target != "a.miek.nl." {
+		t.Fatalf("Expected target of %s, got %s", "a.miek.nl.", r.Answer[0].(*dns.CNAME).Target)
+	}
+	if r.Answer[1].Header().Name != "a.miek.nl." {
+		t.Fatalf("Expected name of %s, got %s", "a.miek.nl.", r.Answer[1].Header().Name)
+	}
+}