libnetwork: move resolver tests that were skipped on Windows

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

libnetwork/resolver_test.go

@@ -5,7 +5,6 @@ import (
 	"encoding/hex"
 	"errors"
 	"net"
-	"runtime"
 	"syscall"
 	"testing"
 	"time"
@@ -16,7 +15,6 @@ import (
 	"github.com/sirupsen/logrus"
 	"gotest.tools/v3/assert"
 	is "gotest.tools/v3/assert/cmp"
-	"gotest.tools/v3/skip"
 )
 
 // a simple/null address type that will be used to fake a local address for unit testing
@@ -95,102 +93,6 @@ func checkDNSRRType(t *testing.T, actual, expected uint16) {
 	}
 }
 
-func TestDNSIPQuery(t *testing.T) {
-	skip.If(t, runtime.GOOS == "windows", "test only works on linux")
-
-	defer netnsutils.SetupTestOSContext(t)()
-	c, err := New()
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer c.Stop()
-
-	n, err := c.NewNetwork("bridge", "dtnet1", "", nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer func() {
-		if err := n.Delete(); err != nil {
-			t.Fatal(err)
-		}
-	}()
-
-	ep, err := n.CreateEndpoint("testep")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	sb, err := c.NewSandbox("c1")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	defer func() {
-		if err := sb.Delete(); err != nil {
-			t.Fatal(err)
-		}
-	}()
-
-	// we need the endpoint only to populate ep_list for the sandbox as part of resolve_name
-	// it is not set as a target for name resolution and does not serve any other purpose
-	err = ep.Join(sb)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// add service records which are used to resolve names. These are the real targets for the DNS querries
-	n.addSvcRecords("ep1", "name1", "svc1", net.ParseIP("192.168.0.1"), net.IP{}, true, "test")
-
-	w := new(tstwriter)
-	// the unit tests right now will focus on non-proxyed DNS requests
-	r := NewResolver(resolverIPSandbox, false, sb)
-
-	// test name1's IP is resolved correctly with the default A type query
-	// Also make sure DNS lookups are case insensitive
-	names := []string{"name1", "NaMe1"}
-	for _, name := range names {
-		q := new(dns.Msg)
-		q.SetQuestion(name, dns.TypeA)
-		r.serveDNS(w, q)
-		resp := w.GetResponse()
-		checkNonNullResponse(t, resp)
-		t.Log("Response: ", resp.String())
-		checkDNSResponseCode(t, resp, dns.RcodeSuccess)
-		checkDNSAnswersCount(t, resp, 1)
-		checkDNSRRType(t, resp.Answer[0].Header().Rrtype, dns.TypeA)
-		if answer, ok := resp.Answer[0].(*dns.A); ok {
-			if !answer.A.Equal(net.ParseIP("192.168.0.1")) {
-				t.Fatalf("IP response in Answer %v does not match 192.168.0.1", answer.A)
-			}
-		} else {
-			t.Fatal("Answer of type A not found")
-		}
-		w.ClearResponse()
-	}
-
-	// test MX query with name1 results in Success response with 0 answer records
-	q := new(dns.Msg)
-	q.SetQuestion("name1", dns.TypeMX)
-	r.serveDNS(w, q)
-	resp := w.GetResponse()
-	checkNonNullResponse(t, resp)
-	t.Log("Response: ", resp.String())
-	checkDNSResponseCode(t, resp, dns.RcodeSuccess)
-	checkDNSAnswersCount(t, resp, 0)
-	w.ClearResponse()
-
-	// test MX query with non existent name results in ServFail response with 0 answer records
-	// since this is a unit test env, we disable proxying DNS above which results in ServFail rather than NXDOMAIN
-	q = new(dns.Msg)
-	q.SetQuestion("nonexistent", dns.TypeMX)
-	r.serveDNS(w, q)
-	resp = w.GetResponse()
-	checkNonNullResponse(t, resp)
-	t.Log("Response: ", resp.String())
-	checkDNSResponseCode(t, resp, dns.RcodeServerFailure)
-	w.ClearResponse()
-}
-
 func newDNSHandlerServFailOnce(requests *int) func(w dns.ResponseWriter, r *dns.Msg) {
 	return func(w dns.ResponseWriter, r *dns.Msg) {
 		m := new(dns.Msg)
@@ -234,79 +136,6 @@ func waitForLocalDNSServer(t *testing.T) {
 	}
 }
 
-func TestDNSProxyServFail(t *testing.T) {
-	skip.If(t, runtime.GOOS == "windows", "test only works on linux")
-
-	osctx := netnsutils.SetupTestOSContextEx(t)
-	defer osctx.Cleanup(t)
-
-	c, err := New()
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer c.Stop()
-
-	n, err := c.NewNetwork("bridge", "dtnet2", "", nil)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer func() {
-		if err := n.Delete(); err != nil {
-			t.Fatal(err)
-		}
-	}()
-
-	sb, err := c.NewSandbox("c1")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	defer func() {
-		if err := sb.Delete(); err != nil {
-			t.Fatal(err)
-		}
-	}()
-
-	var nRequests int
-	// initialize a local DNS server and configure it to fail the first query
-	dns.HandleFunc(".", newDNSHandlerServFailOnce(&nRequests))
-	// use TCP for predictable results. Connection tests (to figure out DNS server initialization) don't work with UDP
-	server := &dns.Server{Addr: "127.0.0.1:53", Net: "tcp"}
-	srvErrCh := make(chan error, 1)
-	osctx.Go(t, func() {
-		srvErrCh <- server.ListenAndServe()
-	})
-	defer func() {
-		server.Shutdown() //nolint:errcheck
-		if err := <-srvErrCh; err != nil {
-			t.Error(err)
-		}
-	}()
-
-	waitForLocalDNSServer(t)
-	t.Log("DNS Server can be reached")
-
-	w := new(tstwriter)
-	r := NewResolver(resolverIPSandbox, true, sb)
-	q := new(dns.Msg)
-	q.SetQuestion("name1.", dns.TypeA)
-
-	var localDNSEntries []extDNSEntry
-	extTestDNSEntry := extDNSEntry{IPStr: "127.0.0.1", HostLoopback: true}
-
-	// configure two external DNS entries and point both to local DNS server thread
-	localDNSEntries = append(localDNSEntries, extTestDNSEntry)
-	localDNSEntries = append(localDNSEntries, extTestDNSEntry)
-
-	// this should generate two requests: the first will fail leading to a retry
-	r.SetExtServers(localDNSEntries)
-	r.serveDNS(w, q)
-	if nRequests != 2 {
-		t.Fatalf("Expected 2 DNS querries. Found: %d", nRequests)
-	}
-	t.Logf("Expected number of DNS requests generated")
-}
-
 // Packet 24 extracted from
 // https://gist.github.com/vojtad/3bac63b8c91b1ec50e8d8b36047317fa/raw/7d75eb3d3448381bf252ae55ea5123a132c46658/host.pcap
 // (https://github.com/moby/moby/issues/44575)

libnetwork/resolver_unix_test.go

@@ -0,0 +1,178 @@
+//go:build !windows
+
+package libnetwork
+
+import (
+	"net"
+	"testing"
+
+	"github.com/docker/docker/internal/testutils/netnsutils"
+	"github.com/miekg/dns"
+)
+
+// test only works on linux
+func TestDNSIPQuery(t *testing.T) {
+	defer netnsutils.SetupTestOSContext(t)()
+	c, err := New()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Stop()
+
+	n, err := c.NewNetwork("bridge", "dtnet1", "", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() {
+		if err := n.Delete(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	ep, err := n.CreateEndpoint("testep")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sb, err := c.NewSandbox("c1")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer func() {
+		if err := sb.Delete(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	// we need the endpoint only to populate ep_list for the sandbox as part of resolve_name
+	// it is not set as a target for name resolution and does not serve any other purpose
+	err = ep.Join(sb)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// add service records which are used to resolve names. These are the real targets for the DNS querries
+	n.addSvcRecords("ep1", "name1", "svc1", net.ParseIP("192.168.0.1"), net.IP{}, true, "test")
+
+	w := new(tstwriter)
+	// the unit tests right now will focus on non-proxyed DNS requests
+	r := NewResolver(resolverIPSandbox, false, sb)
+
+	// test name1's IP is resolved correctly with the default A type query
+	// Also make sure DNS lookups are case insensitive
+	names := []string{"name1", "NaMe1"}
+	for _, name := range names {
+		q := new(dns.Msg)
+		q.SetQuestion(name, dns.TypeA)
+		r.serveDNS(w, q)
+		resp := w.GetResponse()
+		checkNonNullResponse(t, resp)
+		t.Log("Response: ", resp.String())
+		checkDNSResponseCode(t, resp, dns.RcodeSuccess)
+		checkDNSAnswersCount(t, resp, 1)
+		checkDNSRRType(t, resp.Answer[0].Header().Rrtype, dns.TypeA)
+		if answer, ok := resp.Answer[0].(*dns.A); ok {
+			if !answer.A.Equal(net.ParseIP("192.168.0.1")) {
+				t.Fatalf("IP response in Answer %v does not match 192.168.0.1", answer.A)
+			}
+		} else {
+			t.Fatal("Answer of type A not found")
+		}
+		w.ClearResponse()
+	}
+
+	// test MX query with name1 results in Success response with 0 answer records
+	q := new(dns.Msg)
+	q.SetQuestion("name1", dns.TypeMX)
+	r.serveDNS(w, q)
+	resp := w.GetResponse()
+	checkNonNullResponse(t, resp)
+	t.Log("Response: ", resp.String())
+	checkDNSResponseCode(t, resp, dns.RcodeSuccess)
+	checkDNSAnswersCount(t, resp, 0)
+	w.ClearResponse()
+
+	// test MX query with non existent name results in ServFail response with 0 answer records
+	// since this is a unit test env, we disable proxying DNS above which results in ServFail rather than NXDOMAIN
+	q = new(dns.Msg)
+	q.SetQuestion("nonexistent", dns.TypeMX)
+	r.serveDNS(w, q)
+	resp = w.GetResponse()
+	checkNonNullResponse(t, resp)
+	t.Log("Response: ", resp.String())
+	checkDNSResponseCode(t, resp, dns.RcodeServerFailure)
+	w.ClearResponse()
+}
+
+// test only works on linux
+func TestDNSProxyServFail(t *testing.T) {
+	osctx := netnsutils.SetupTestOSContextEx(t)
+	defer osctx.Cleanup(t)
+
+	c, err := New()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Stop()
+
+	n, err := c.NewNetwork("bridge", "dtnet2", "", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() {
+		if err := n.Delete(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	sb, err := c.NewSandbox("c1")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer func() {
+		if err := sb.Delete(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	var nRequests int
+	// initialize a local DNS server and configure it to fail the first query
+	dns.HandleFunc(".", newDNSHandlerServFailOnce(&nRequests))
+	// use TCP for predictable results. Connection tests (to figure out DNS server initialization) don't work with UDP
+	server := &dns.Server{Addr: "127.0.0.1:53", Net: "tcp"}
+	srvErrCh := make(chan error, 1)
+	osctx.Go(t, func() {
+		srvErrCh <- server.ListenAndServe()
+	})
+	defer func() {
+		server.Shutdown() //nolint:errcheck
+		if err := <-srvErrCh; err != nil {
+			t.Error(err)
+		}
+	}()
+
+	waitForLocalDNSServer(t)
+	t.Log("DNS Server can be reached")
+
+	w := new(tstwriter)
+	r := NewResolver(resolverIPSandbox, true, sb)
+	q := new(dns.Msg)
+	q.SetQuestion("name1.", dns.TypeA)
+
+	var localDNSEntries []extDNSEntry
+	extTestDNSEntry := extDNSEntry{IPStr: "127.0.0.1", HostLoopback: true}
+
+	// configure two external DNS entries and point both to local DNS server thread
+	localDNSEntries = append(localDNSEntries, extTestDNSEntry)
+	localDNSEntries = append(localDNSEntries, extTestDNSEntry)
+
+	// this should generate two requests: the first will fail leading to a retry
+	r.SetExtServers(localDNSEntries)
+	r.serveDNS(w, q)
+	if nRequests != 2 {
+		t.Fatalf("Expected 2 DNS querries. Found: %d", nRequests)
+	}
+	t.Logf("Expected number of DNS requests generated")
+}