WIP Issue 3138 - Conformance Tests for BackendTLSPolicy - normative

Author: candita

conformance/echo-basic/echo-basic.go

@@ -23,13 +23,16 @@ import (
 	"encoding/pem"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"os"
 	"regexp"
 	"strconv"
 	"strings"
 	"time"
 
+	"github.com/paultag/sniff/parser"
+
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/h2c"
 	"golang.org/x/net/websocket"
@@ -48,15 +51,19 @@ type RequestAssertions struct {
 	Context `json:",inline"`
 
 	TLS *TLSAssertions `json:"tls,omitempty"`
+	SNI string         `json:"sni"`
 }
 
 // TLSAssertions contains information about the TLS connection.
 type TLSAssertions struct {
-	Version            string   `json:"version"`
-	PeerCertificates   []string `json:"peerCertificates,omitempty"`
-	ServerName         string   `json:"serverName"`
-	NegotiatedProtocol string   `json:"negotiatedProtocol,omitempty"`
-	CipherSuite        string   `json:"cipherSuite"`
+	Version          string   `json:"version"`
+	PeerCertificates []string `json:"peerCertificates,omitempty"`
+	// ClientCertificates are used by the gateway to authorize itself to the backend.
+	ClientCertificates []string `json:"clientCertificates,omitempty"`
+	// ServerName is the SNI.
+	ServerName         string `json:"serverName"`
+	NegotiatedProtocol string `json:"negotiatedProtocol,omitempty"`
+	CipherSuite        string `json:"cipherSuite"`
 }
 
 type preserveSlashes struct {
@@ -109,6 +116,7 @@ func main() {
 	httpMux.HandleFunc("/health", healthHandler)
 	httpMux.HandleFunc("/status/", statusHandler)
 	httpMux.HandleFunc("/", echoHandler)
+	httpMux.HandleFunc("/backendTLS", echoHandler)
 	httpMux.Handle("/ws", websocket.Handler(wsHandler))
 	httpHandler := &preserveSlashes{httpMux}
 
@@ -124,11 +132,14 @@ func main() {
 
 	go runH2CServer(h2cPort, errchan)
 
-	// Enable HTTPS if certificate and private key are given.
-	if os.Getenv("TLS_SERVER_CERT") != "" && os.Getenv("TLS_SERVER_PRIVKEY") != "" {
+	// Enable HTTPS if server certificate and private key are given. Enable secure backend if client certificate and key are given.
+	if os.Getenv("TLS_SERVER_CERT") != "" && os.Getenv("TLS_SERVER_PRIVKEY") != "" ||
+		os.Getenv("TLS_CLIENT_CERT") != "" && os.Getenv("TLS_CLIENT_KEY") != "" {
 		go func() {
 			fmt.Printf("Starting server, listening on port %s (https)\n", httpsPort)
-			err := listenAndServeTLS(fmt.Sprintf(":%s", httpsPort), os.Getenv("TLS_SERVER_CERT"), os.Getenv("TLS_SERVER_PRIVKEY"), os.Getenv("TLS_CLIENT_CACERTS"), httpHandler)
+			// TODO - probably don't need to pass these in.
+			err := listenAndServeTLS(fmt.Sprintf(":%s", httpsPort), os.Getenv("TLS_SERVER_CERT"), os.Getenv("TLS_SERVER_PRIVKEY"),
+				os.Getenv("TLS_CLIENT_CACERTS"), os.Getenv("TLS_CLIENT_CERT"), os.Getenv("TLS_CLIENT_KEY"), httpHandler)
 			if err != nil {
 				errchan <- err
 			}
@@ -201,15 +212,27 @@ func runH2CServer(h2cPort string, errchan chan<- error) {
 }
 
 func echoHandler(w http.ResponseWriter, r *http.Request) {
+	var sni string
+
 	fmt.Printf("Echoing back request made to %s to client (%s)\n", r.RequestURI, r.RemoteAddr)
 
 	// If the request has form ?delay=[:duration] wait for duration
 	// For example, ?delay=10s will cause the response to wait 10s before responding
-	if err := delayResponse(r); err != nil {
+	err := delayResponse(r)
+	if err != nil {
 		processError(w, err, http.StatusInternalServerError)
 		return
 	}
 
+	// If the request was made to URI backendTLS, then get the server name indication and
+	// add it to the RequestAssertions.  It will be echoed back later.
+	if strings.Contains(r.RequestURI, "backendTLS") {
+		sni, err = sniffForSNI(r.RemoteAddr)
+		if err != nil {
+			// Todo: research if for some test cases there won't be one
+		}
+	}
+
 	requestAssertions := RequestAssertions{
 		r.RequestURI,
 		r.Host,
@@ -220,6 +243,7 @@ func echoHandler(w http.ResponseWriter, r *http.Request) {
 		context,
 
 		tlsStateToAssertions(r.TLS),
+		sni,
 	}
 
 	js, err := json.MarshalIndent(requestAssertions, "", " ")
@@ -232,6 +256,7 @@ func echoHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 	w.Header().Set("X-Content-Type-Options", "nosniff")
 	_, _ = w.Write(js)
+
 }
 
 func writeEchoResponseHeaders(w http.ResponseWriter, headers http.Header) {
@@ -267,7 +292,7 @@ func processError(w http.ResponseWriter, err error, code int) { //nolint:unparam
 	_, _ = w.Write(body)
 }
 
-func listenAndServeTLS(addr string, serverCert string, serverPrivKey string, clientCA string, handler http.Handler) error {
+func listenAndServeTLS(addr string, serverCert string, serverPrivKey string, clientCA string, clientCert string, clientPrivKey string, handler http.Handler) error {
 	var config tls.Config
 
 	// Optionally enable client certificate validation when client CA certificates are given.
@@ -296,6 +321,40 @@ func listenAndServeTLS(addr string, serverCert string, serverPrivKey string, cli
 	return srv.ListenAndServeTLS(serverCert, serverPrivKey)
 }
 
+// sniffForSNI uses the request address to listen for the incoming TLS connection,
+// and tries to find the server name indication from that connection.
+func sniffForSNI(addr string) (string, error) {
+	var sni string
+
+	// Listen to get the SNI, and store in config.
+	listener, err := net.Listen("tcp", addr)
+	if err != nil {
+		return "", err
+	}
+	defer listener.Close()
+
+	for {
+		conn, err := listener.Accept()
+		if err != nil {
+			return "", err
+		}
+		data := make([]byte, 4096)
+		_, err = conn.Read(data)
+		if err != nil {
+			return "", fmt.Errorf("could not read socket: %v", err)
+		}
+		// Take an incoming TLS Client Hello and return the SNI name.
+		sni, err = parser.GetHostname(data[:])
+		if err != nil {
+			return "", fmt.Errorf("error getting SNI: %v", err)
+		}
+		if sni == "" {
+			return "", fmt.Errorf("no server name indication found")
+		}
+		return sni, nil
+	}
+}
+
 func tlsStateToAssertions(connectionState *tls.ConnectionState) *TLSAssertions {
 	if connectionState != nil {
 		var state TLSAssertions

conformance/utils/kubernetes/certificate.go

@@ -117,3 +117,79 @@ func generateRSACert(hosts []string, keyOut, certOut io.Writer) error {
 
 	return nil
 }
+
+// MustCreateCASignedCertSecret will create a secret using a CA Certificate, and public and private key for that certificate.
+func MustCreateCASignedCertSecret(t *testing.T, namespace, secretName string, hosts []string) *corev1.Secret {
+	require.NotEmpty(t, hosts, "require a non-empty hosts for Subject Alternate Name values")
+
+	var serverKey, serverCert bytes.Buffer
+
+	require.NoError(t, generateCACert(hosts, &serverKey, &serverCert), "failed to generate CA certificate")
+
+	data := map[string][]byte{
+		corev1.TLSCertKey:       serverCert.Bytes(),
+		corev1.TLSPrivateKeyKey: serverKey.Bytes(),
+	}
+
+	newSecret := &corev1.Secret{
+		ObjectMeta: metav1.ObjectMeta{
+			Namespace: namespace,
+			Name:      secretName,
+		},
+		Type: corev1.SecretTypeTLS,
+		Data: data,
+	}
+
+	return newSecret
+}
+
+// generateCACert generates a CA Certificate signed certificate valid for a year.
+func generateCACert(hosts []string, keyOut, certOut io.Writer) error {
+	// Create the CA certificate.
+	ca := &x509.Certificate{
+		SerialNumber: big.NewInt(2024),
+		Subject: pkix.Name{
+			Organization:  []string{"Kubernetes Gateway API"},
+			Country:       []string{"US"},
+			Province:      []string{""},
+			Locality:      []string{"Boston"},
+			StreetAddress: []string{"Melnea Cass Blvd"},
+			PostalCode:    []string{"02120"},
+		},
+		NotBefore:             time.Now(),
+		NotAfter:              time.Now().AddDate(1, 0, 0),
+		IsCA:                  true, // Indicates this is a CA Certificate.
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth, x509.ExtKeyUsageServerAuth},
+		KeyUsage:              x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign,
+		BasicConstraintsValid: true,
+	}
+
+	for _, h := range hosts {
+		if ip := net.ParseIP(h); ip != nil {
+			ca.IPAddresses = append(ca.IPAddresses, ip)
+		} else {
+			ca.DNSNames = append(ca.DNSNames, h)
+		}
+	}
+
+	// Generate the private key.
+	caPrivKey, err := rsa.GenerateKey(rand.Reader, rsaBits)
+	if err != nil {
+		return err
+	}
+
+	// Generate the certificate using the CA certificate.
+	caBytes, err := x509.CreateCertificate(rand.Reader, ca, ca, &caPrivKey.PublicKey, caPrivKey)
+	if err != nil {
+		return err
+	}
+
+	if err := pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: caBytes}); err != nil {
+		return fmt.Errorf("failed creating cert: %w", err)
+	}
+
+	if err := pem.Encode(keyOut, &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(caPrivKey)}); err != nil {
+		return fmt.Errorf("failed creating key: %w", err)
+	}
+	return nil
+}

conformance/utils/suite/suite.go

@@ -353,6 +353,8 @@ func (suite *ConformanceTestSuite) Setup(t *testing.T, tests []ConformanceTest)
 		suite.Applier.MustApplyObjectsWithCleanup(t, suite.Client, suite.TimeoutConfig, []client.Object{secret}, suite.Cleanup)
 		secret = kubernetes.MustCreateSelfSignedCertSecret(t, "gateway-conformance-app-backend", "tls-passthrough-checks-certificate", []string{"abc.example.com"})
 		suite.Applier.MustApplyObjectsWithCleanup(t, suite.Client, suite.TimeoutConfig, []client.Object{secret}, suite.Cleanup)
+		caSecret := kubernetes.MustCreateCASignedCertSecret(t, "gateway-conformance-infra", "backend-tls-checks-certificate", []string{"abc.example.com"})
+		suite.Applier.MustApplyObjectsWithCleanup(t, suite.Client, suite.TimeoutConfig, []client.Object{caSecret}, suite.Cleanup)
 
 		tlog.Logf(t, "Test Setup: Ensuring Gateways and Pods from base manifests are ready")
 		namespaces := []string{

go.mod

@@ -5,6 +5,7 @@ go 1.22.0
 require (
 	github.com/ahmetb/gen-crd-api-reference-docs v0.3.0
 	github.com/miekg/dns v1.1.58
+	github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732
 	github.com/stretchr/testify v1.9.0
 	golang.org/x/net v0.24.0
 	golang.org/x/sync v0.7.0

go.sum

@@ -97,6 +97,8 @@ github.com/onsi/ginkgo/v2 v2.17.1 h1:V++EzdbhI4ZV4ev0UTIj0PzhzOcReJFyJaLjtSF55M8
 github.com/onsi/ginkgo/v2 v2.17.1/go.mod h1:llBI3WDLL9Z6taip6f33H76YcWtJv+7R3HigUjbIBOs=
 github.com/onsi/gomega v1.33.0 h1:snPCflnZrpMsy94p4lXVEkHo12lmPnc3vY5XBbreexE=
 github.com/onsi/gomega v1.33.0/go.mod h1:+925n5YtiFsLzzafLUHzVMBpvvRAzrydIBiSIxjX3wY=
+github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732 h1:nkseUkzjazCNyGhkRwnJ1OiHSwMXazsJQx+Ci+oVLEM=
+github.com/paultag/sniff v0.0.0-20200207005214-cf7e4d167732/go.mod h1:J3XXNGJINXLa4yIivdUT0Ad/srv2q0pSOWbbm6El2EY=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=