apiserver/plugin/pkg/authorizer/webhook/webhook_v1beta1_test.go

660 lines
20 KiB
Go

/*
Copyright 2016 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package webhook
import (
"context"
"crypto/tls"
"crypto/x509"
"encoding/json"
"fmt"
"io"
"net/http"
"net/http/httptest"
"net/url"
"os"
"path/filepath"
"reflect"
"strings"
"testing"
"text/template"
"time"
"github.com/google/go-cmp/cmp"
authorizationv1beta1 "k8s.io/api/authorization/v1beta1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
authzconfig "k8s.io/apiserver/pkg/apis/apiserver"
"k8s.io/apiserver/pkg/authentication/user"
"k8s.io/apiserver/pkg/authorization/authorizer"
authorizationcel "k8s.io/apiserver/pkg/authorization/cel"
webhookutil "k8s.io/apiserver/pkg/util/webhook"
v1 "k8s.io/client-go/tools/clientcmd/api/v1"
)
func TestV1beta1NewFromConfig(t *testing.T) {
dir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
defer os.RemoveAll(dir)
data := struct {
CA string
Cert string
Key string
}{
CA: filepath.Join(dir, "ca.pem"),
Cert: filepath.Join(dir, "clientcert.pem"),
Key: filepath.Join(dir, "clientkey.pem"),
}
files := []struct {
name string
data []byte
}{
{data.CA, caCert},
{data.Cert, clientCert},
{data.Key, clientKey},
}
for _, file := range files {
if err := os.WriteFile(file.name, file.data, 0400); err != nil {
t.Fatal(err)
}
}
tests := []struct {
msg string
configTmpl string
wantErr bool
}{
{
msg: "a single cluster and single user",
configTmpl: `
clusters:
- cluster:
certificate-authority: {{ .CA }}
server: https://authz.example.com
name: foobar
users:
- name: a cluster
user:
client-certificate: {{ .Cert }}
client-key: {{ .Key }}
`,
wantErr: true,
},
{
msg: "multiple clusters with no context",
configTmpl: `
clusters:
- cluster:
certificate-authority: {{ .CA }}
server: https://authz.example.com
name: foobar
- cluster:
certificate-authority: a bad certificate path
server: https://authz.example.com
name: barfoo
users:
- name: a name
user:
client-certificate: {{ .Cert }}
client-key: {{ .Key }}
`,
wantErr: true,
},
{
msg: "multiple clusters with a context",
configTmpl: `
clusters:
- cluster:
certificate-authority: a bad certificate path
server: https://authz.example.com
name: foobar
- cluster:
certificate-authority: {{ .CA }}
server: https://authz.example.com
name: barfoo
users:
- name: a name
user:
client-certificate: {{ .Cert }}
client-key: {{ .Key }}
contexts:
- name: default
context:
cluster: barfoo
user: a name
current-context: default
`,
wantErr: false,
},
{
msg: "cluster with bad certificate path specified",
configTmpl: `
clusters:
- cluster:
certificate-authority: a bad certificate path
server: https://authz.example.com
name: foobar
- cluster:
certificate-authority: {{ .CA }}
server: https://authz.example.com
name: barfoo
users:
- name: a name
user:
client-certificate: {{ .Cert }}
client-key: {{ .Key }}
contexts:
- name: default
context:
cluster: foobar
user: a name
current-context: default
`,
wantErr: true,
},
}
for _, tt := range tests {
// Use a closure so defer statements trigger between loop iterations.
err := func() error {
tempfile, err := os.CreateTemp("", "")
if err != nil {
return err
}
p := tempfile.Name()
defer os.Remove(p)
tmpl, err := template.New("test").Parse(tt.configTmpl)
if err != nil {
return fmt.Errorf("failed to parse test template: %v", err)
}
if err := tmpl.Execute(tempfile, data); err != nil {
return fmt.Errorf("failed to execute test template: %v", err)
}
// Create a new authorizer
clientConfig, err := webhookutil.LoadKubeconfig(p, nil)
if err != nil {
return err
}
sarClient, err := subjectAccessReviewInterfaceFromConfig(clientConfig, "v1beta1", testRetryBackoff)
if err != nil {
return fmt.Errorf("error building sar client: %v", err)
}
_, err = newWithBackoff(sarClient, 0, 0, testRetryBackoff, authorizer.DecisionNoOpinion, []authzconfig.WebhookMatchCondition{}, noopAuthorizerMetrics(), authorizationcel.NewDefaultCompiler(), "")
return err
}()
if err != nil && !tt.wantErr {
t.Errorf("failed to load plugin from config %q: %v", tt.msg, err)
}
if err == nil && tt.wantErr {
t.Errorf("wanted an error when loading config, did not get one: %q", tt.msg)
}
}
}
// V1beta1Service mocks a remote service.
type V1beta1Service interface {
Review(*authorizationv1beta1.SubjectAccessReview)
HTTPStatusCode() int
}
// NewV1beta1TestServer wraps a V1beta1Service as an httptest.Server.
func NewV1beta1TestServer(s V1beta1Service, cert, key, caCert []byte) (*httptest.Server, error) {
const webhookPath = "/testserver"
var tlsConfig *tls.Config
if cert != nil {
cert, err := tls.X509KeyPair(cert, key)
if err != nil {
return nil, err
}
tlsConfig = &tls.Config{Certificates: []tls.Certificate{cert}}
}
if caCert != nil {
rootCAs := x509.NewCertPool()
rootCAs.AppendCertsFromPEM(caCert)
if tlsConfig == nil {
tlsConfig = &tls.Config{}
}
tlsConfig.ClientCAs = rootCAs
tlsConfig.ClientAuth = tls.RequireAndVerifyClientCert
}
serveHTTP := func(w http.ResponseWriter, r *http.Request) {
if r.Method != "POST" {
http.Error(w, fmt.Sprintf("unexpected method: %v", r.Method), http.StatusMethodNotAllowed)
return
}
if r.URL.Path != webhookPath {
http.Error(w, fmt.Sprintf("unexpected path: %v", r.URL.Path), http.StatusNotFound)
return
}
var review authorizationv1beta1.SubjectAccessReview
bodyData, _ := io.ReadAll(r.Body)
if err := json.Unmarshal(bodyData, &review); err != nil {
http.Error(w, fmt.Sprintf("failed to decode body: %v", err), http.StatusBadRequest)
return
}
// ensure we received the serialized review as expected
if review.APIVersion != "authorization.k8s.io/v1beta1" {
http.Error(w, fmt.Sprintf("wrong api version: %s", string(bodyData)), http.StatusBadRequest)
return
}
// once we have a successful request, always call the review to record that we were called
s.Review(&review)
if s.HTTPStatusCode() < 200 || s.HTTPStatusCode() >= 300 {
http.Error(w, "HTTP Error", s.HTTPStatusCode())
return
}
type status struct {
Allowed bool `json:"allowed"`
Reason string `json:"reason"`
EvaluationError string `json:"evaluationError"`
}
resp := struct {
APIVersion string `json:"apiVersion"`
Status status `json:"status"`
}{
APIVersion: authorizationv1beta1.SchemeGroupVersion.String(),
Status: status{review.Status.Allowed, review.Status.Reason, review.Status.EvaluationError},
}
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(resp)
}
server := httptest.NewUnstartedServer(http.HandlerFunc(serveHTTP))
server.TLS = tlsConfig
server.StartTLS()
// Adjust the path to point to our custom path
serverURL, _ := url.Parse(server.URL)
serverURL.Path = webhookPath
server.URL = serverURL.String()
return server, nil
}
// A service that can be set to allow all or deny all authorization requests.
type mockV1beta1Service struct {
allow bool
statusCode int
called int
}
func (m *mockV1beta1Service) Review(r *authorizationv1beta1.SubjectAccessReview) {
m.called++
r.Status.Allowed = m.allow
}
func (m *mockV1beta1Service) Allow() { m.allow = true }
func (m *mockV1beta1Service) Deny() { m.allow = false }
func (m *mockV1beta1Service) HTTPStatusCode() int { return m.statusCode }
// newV1beta1Authorizer creates a temporary kubeconfig file from the provided arguments and attempts to load
// a new WebhookAuthorizer from it.
func newV1beta1Authorizer(callbackURL string, clientCert, clientKey, ca []byte, cacheTime time.Duration) (*WebhookAuthorizer, error) {
tempfile, err := os.CreateTemp("", "")
if err != nil {
return nil, err
}
p := tempfile.Name()
defer os.Remove(p)
config := v1.Config{
Clusters: []v1.NamedCluster{
{
Cluster: v1.Cluster{Server: callbackURL, CertificateAuthorityData: ca},
},
},
AuthInfos: []v1.NamedAuthInfo{
{
AuthInfo: v1.AuthInfo{ClientCertificateData: clientCert, ClientKeyData: clientKey},
},
},
}
if err := json.NewEncoder(tempfile).Encode(config); err != nil {
return nil, err
}
clientConfig, err := webhookutil.LoadKubeconfig(p, nil)
if err != nil {
return nil, err
}
sarClient, err := subjectAccessReviewInterfaceFromConfig(clientConfig, "v1beta1", testRetryBackoff)
if err != nil {
return nil, fmt.Errorf("error building sar client: %v", err)
}
return newWithBackoff(sarClient, cacheTime, cacheTime, testRetryBackoff, authorizer.DecisionNoOpinion, []authzconfig.WebhookMatchCondition{}, noopAuthorizerMetrics(), authorizationcel.NewDefaultCompiler(), "")
}
func TestV1beta1TLSConfig(t *testing.T) {
tests := []struct {
test string
clientCert, clientKey, clientCA []byte
serverCert, serverKey, serverCA []byte
wantAuth, wantErr bool
}{
{
test: "TLS setup between client and server",
clientCert: clientCert, clientKey: clientKey, clientCA: caCert,
serverCert: serverCert, serverKey: serverKey, serverCA: caCert,
wantAuth: true,
},
{
test: "Server does not require client auth",
clientCA: caCert,
serverCert: serverCert, serverKey: serverKey,
wantAuth: true,
},
{
test: "Server does not require client auth, client provides it",
clientCert: clientCert, clientKey: clientKey, clientCA: caCert,
serverCert: serverCert, serverKey: serverKey,
wantAuth: true,
},
{
test: "Client does not trust server",
clientCert: clientCert, clientKey: clientKey,
serverCert: serverCert, serverKey: serverKey,
wantErr: true,
},
{
test: "Server does not trust client",
clientCert: clientCert, clientKey: clientKey, clientCA: caCert,
serverCert: serverCert, serverKey: serverKey, serverCA: badCACert,
wantErr: true,
},
{
// Plugin does not support insecure configurations.
test: "Server is using insecure connection",
wantErr: true,
},
}
for _, tt := range tests {
// Use a closure so defer statements trigger between loop iterations.
func() {
service := new(mockV1beta1Service)
service.statusCode = 200
server, err := NewV1beta1TestServer(service, tt.serverCert, tt.serverKey, tt.serverCA)
if err != nil {
t.Errorf("%s: failed to create server: %v", tt.test, err)
return
}
defer server.Close()
wh, err := newV1beta1Authorizer(server.URL, tt.clientCert, tt.clientKey, tt.clientCA, 0)
if err != nil {
t.Errorf("%s: failed to create client: %v", tt.test, err)
return
}
attr := authorizer.AttributesRecord{User: &user.DefaultInfo{}}
// Allow all and see if we get an error.
service.Allow()
decision, _, err := wh.Authorize(context.Background(), attr)
if tt.wantAuth {
if decision != authorizer.DecisionAllow {
t.Errorf("expected successful authorization")
}
} else {
if decision == authorizer.DecisionAllow {
t.Errorf("expected failed authorization")
}
}
if tt.wantErr {
if err == nil {
t.Errorf("expected error making authorization request: %v", err)
}
return
}
if err != nil {
t.Errorf("%s: failed to authorize with AllowAll policy: %v", tt.test, err)
return
}
service.Deny()
if decision, _, _ := wh.Authorize(context.Background(), attr); decision == authorizer.DecisionAllow {
t.Errorf("%s: incorrectly authorized with DenyAll policy", tt.test)
}
}()
}
}
// recorderV1beta1Service records all access review requests.
type recorderV1beta1Service struct {
last authorizationv1beta1.SubjectAccessReview
err error
}
func (rec *recorderV1beta1Service) Review(r *authorizationv1beta1.SubjectAccessReview) {
rec.last = authorizationv1beta1.SubjectAccessReview{}
rec.last = *r
r.Status.Allowed = true
}
func (rec *recorderV1beta1Service) Last() (authorizationv1beta1.SubjectAccessReview, error) {
return rec.last, rec.err
}
func (rec *recorderV1beta1Service) HTTPStatusCode() int { return 200 }
func TestV1beta1Webhook(t *testing.T) {
serv := new(recorderV1beta1Service)
s, err := NewV1beta1TestServer(serv, serverCert, serverKey, caCert)
if err != nil {
t.Fatal(err)
}
defer s.Close()
wh, err := newV1beta1Authorizer(s.URL, clientCert, clientKey, caCert, 0)
if err != nil {
t.Fatal(err)
}
expTypeMeta := metav1.TypeMeta{
APIVersion: "authorization.k8s.io/v1beta1",
Kind: "SubjectAccessReview",
}
tests := []struct {
attr authorizer.Attributes
want authorizationv1beta1.SubjectAccessReview
}{
{
attr: authorizer.AttributesRecord{User: &user.DefaultInfo{}},
want: authorizationv1beta1.SubjectAccessReview{
TypeMeta: expTypeMeta,
Spec: authorizationv1beta1.SubjectAccessReviewSpec{
NonResourceAttributes: &authorizationv1beta1.NonResourceAttributes{},
},
},
},
{
attr: authorizer.AttributesRecord{User: &user.DefaultInfo{Name: "jane"}},
want: authorizationv1beta1.SubjectAccessReview{
TypeMeta: expTypeMeta,
Spec: authorizationv1beta1.SubjectAccessReviewSpec{
User: "jane",
NonResourceAttributes: &authorizationv1beta1.NonResourceAttributes{},
},
},
},
{
attr: authorizer.AttributesRecord{
User: &user.DefaultInfo{
Name: "jane",
UID: "1",
Groups: []string{"group1", "group2"},
},
Verb: "GET",
Namespace: "kittensandponies",
APIGroup: "group3",
APIVersion: "v7beta3",
Resource: "pods",
Subresource: "proxy",
Name: "my-pod",
ResourceRequest: true,
Path: "/foo",
},
want: authorizationv1beta1.SubjectAccessReview{
TypeMeta: expTypeMeta,
Spec: authorizationv1beta1.SubjectAccessReviewSpec{
User: "jane",
UID: "1",
Groups: []string{"group1", "group2"},
ResourceAttributes: &authorizationv1beta1.ResourceAttributes{
Verb: "GET",
Namespace: "kittensandponies",
Group: "group3",
Version: "v7beta3",
Resource: "pods",
Subresource: "proxy",
Name: "my-pod",
},
},
},
},
}
for i, tt := range tests {
decision, _, err := wh.Authorize(context.Background(), tt.attr)
if err != nil {
t.Fatal(err)
}
if decision != authorizer.DecisionAllow {
t.Errorf("case %d: authorization failed", i)
continue
}
gotAttr, err := serv.Last()
if err != nil {
t.Errorf("case %d: failed to deserialize webhook request: %v", i, err)
continue
}
if !reflect.DeepEqual(gotAttr, tt.want) {
t.Errorf("case %d: got != want:\n%s", i, cmp.Diff(gotAttr, tt.want))
}
}
}
// TestWebhookCache verifies that error responses from the server are not
// cached, but successful responses are.
func TestV1beta1WebhookCache(t *testing.T) {
serv := new(mockV1beta1Service)
s, err := NewV1beta1TestServer(serv, serverCert, serverKey, caCert)
if err != nil {
t.Fatal(err)
}
defer s.Close()
// Create an authorizer that caches successful responses "forever" (100 days).
wh, err := newV1beta1Authorizer(s.URL, clientCert, clientKey, caCert, 2400*time.Hour)
if err != nil {
t.Fatal(err)
}
aliceAttr := authorizer.AttributesRecord{User: &user.DefaultInfo{Name: "alice"}}
bobAttr := authorizer.AttributesRecord{User: &user.DefaultInfo{Name: "bob"}}
aliceRidiculousAttr := authorizer.AttributesRecord{
User: &user.DefaultInfo{Name: "alice"},
ResourceRequest: true,
Verb: strings.Repeat("v", 2000),
APIGroup: strings.Repeat("g", 2000),
APIVersion: strings.Repeat("a", 2000),
Resource: strings.Repeat("r", 2000),
Name: strings.Repeat("n", 2000),
}
bobRidiculousAttr := authorizer.AttributesRecord{
User: &user.DefaultInfo{Name: "bob"},
ResourceRequest: true,
Verb: strings.Repeat("v", 2000),
APIGroup: strings.Repeat("g", 2000),
APIVersion: strings.Repeat("a", 2000),
Resource: strings.Repeat("r", 2000),
Name: strings.Repeat("n", 2000),
}
type webhookCacheTestCase struct {
name string
attr authorizer.AttributesRecord
allow bool
statusCode int
expectedErr bool
expectedAuthorized bool
expectedCalls int
}
tests := []webhookCacheTestCase{
// server error and 429's retry
{name: "server errors retry", attr: aliceAttr, allow: false, statusCode: 500, expectedErr: true, expectedAuthorized: false, expectedCalls: 5},
{name: "429s retry", attr: aliceAttr, allow: false, statusCode: 429, expectedErr: true, expectedAuthorized: false, expectedCalls: 5},
// regular errors return errors but do not retry
{name: "404 doesnt retry", attr: aliceAttr, allow: false, statusCode: 404, expectedErr: true, expectedAuthorized: false, expectedCalls: 1},
{name: "403 doesnt retry", attr: aliceAttr, allow: false, statusCode: 403, expectedErr: true, expectedAuthorized: false, expectedCalls: 1},
{name: "401 doesnt retry", attr: aliceAttr, allow: false, statusCode: 401, expectedErr: true, expectedAuthorized: false, expectedCalls: 1},
// successful responses are cached
{name: "alice successful request", attr: aliceAttr, allow: true, statusCode: 200, expectedErr: false, expectedAuthorized: true, expectedCalls: 1},
// later requests within the cache window don't hit the backend
{name: "alice cached request", attr: aliceAttr, allow: false, statusCode: 500, expectedErr: false, expectedAuthorized: true, expectedCalls: 0},
// a request with different attributes doesn't hit the cache
{name: "bob failed request", attr: bobAttr, allow: false, statusCode: 500, expectedErr: true, expectedAuthorized: false, expectedCalls: 5},
// successful response for other attributes is cached
{name: "bob unauthorized request", attr: bobAttr, allow: false, statusCode: 200, expectedErr: false, expectedAuthorized: false, expectedCalls: 1},
// later requests within the cache window don't hit the backend
{name: "bob unauthorized cached request", attr: bobAttr, allow: false, statusCode: 500, expectedErr: false, expectedAuthorized: false, expectedCalls: 0},
// ridiculous unauthorized requests are not cached.
{name: "ridiculous unauthorized request", attr: bobRidiculousAttr, allow: false, statusCode: 200, expectedErr: false, expectedAuthorized: false, expectedCalls: 1},
// later ridiculous requests within the cache window still hit the backend
{name: "ridiculous unauthorized request again", attr: bobRidiculousAttr, allow: false, statusCode: 200, expectedErr: false, expectedAuthorized: false, expectedCalls: 1},
// ridiculous authorized requests are not cached.
{name: "ridiculous authorized request", attr: aliceRidiculousAttr, allow: true, statusCode: 200, expectedErr: false, expectedAuthorized: true, expectedCalls: 1},
// later ridiculous requests within the cache window still hit the backend
{name: "ridiculous authorized request again", attr: aliceRidiculousAttr, allow: true, statusCode: 200, expectedErr: false, expectedAuthorized: true, expectedCalls: 1},
}
for i, test := range tests {
t.Run(test.name, func(t *testing.T) {
serv.called = 0
serv.allow = test.allow
serv.statusCode = test.statusCode
authorized, _, err := wh.Authorize(context.Background(), test.attr)
if test.expectedErr && err == nil {
t.Fatalf("%d: Expected error", i)
} else if !test.expectedErr && err != nil {
t.Fatalf("%d: unexpected error: %v", i, err)
}
if test.expectedAuthorized != (authorized == authorizer.DecisionAllow) {
t.Errorf("%d: expected authorized=%v, got %v", i, test.expectedAuthorized, authorized)
}
if test.expectedCalls != serv.called {
t.Errorf("%d: expected %d calls, got %d", i, test.expectedCalls, serv.called)
}
})
}
}