package kubeauth import ( "bytes" "encoding/json" "encoding/pem" "fmt" "io/ioutil" "log" "net" "net/http" "net/http/httptest" "net/url" "regexp" "strconv" "strings" "sync" "time" "github.com/hashicorp/consul/sdk/freeport" "github.com/mitchellh/go-testing-interface" "github.com/stretchr/testify/require" authv1 "k8s.io/api/authentication/v1" corev1 "k8s.io/api/core/v1" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/types" ) // TestAPIServer is a way to mock the Kubernetes API server as it is used by // the consul kubernetes auth method. // // - POST /apis/authentication.k8s.io/v1/tokenreviews // - GET /api/v1/namespaces//serviceaccounts/ // type TestAPIServer struct { srv *httptest.Server caCert string returnFunc func() mu sync.Mutex authorizedJWT string // token review and sa read allowedServiceAccountJWT string // general service account replyStatus *authv1.TokenReview // general service account replyRead *corev1.ServiceAccount // general service account } // StartTestAPIServer creates a disposable TestAPIServer and binds it to a // random free port. func StartTestAPIServer(t testing.T) *TestAPIServer { s := &TestAPIServer{} ports := freeport.MustTake(1) s.returnFunc = func() { freeport.Return(ports) } s.srv = httptestNewUnstartedServerWithPort(s, ports[0]) s.srv.Config.ErrorLog = log.New(ioutil.Discard, "", 0) s.srv.StartTLS() bs := s.srv.TLS.Certificates[0].Certificate[0] var buf bytes.Buffer require.NoError(t, pem.Encode(&buf, &pem.Block{Type: "CERTIFICATE", Bytes: bs})) s.caCert = buf.String() return s } // AuthorizeJWT allowlists the given JWT as able to use the API server. func (s *TestAPIServer) AuthorizeJWT(jwt string) { s.mu.Lock() defer s.mu.Unlock() s.authorizedJWT = jwt } // SetAllowedServiceAccount configures the singular known Service Account // installed in this API server. If any of namespace/name/uid/jwt are empty // it removes anything previously configured. // // It is up to the caller to ensure that the provided JWT matches the other // data. func (s *TestAPIServer) SetAllowedServiceAccount( namespace, name, uid, overrideAnnotation, jwt string, ) { s.mu.Lock() defer s.mu.Unlock() if namespace == "" || name == "" || uid == "" || jwt == "" { s.allowedServiceAccountJWT = "" s.replyStatus = nil s.replyRead = nil return } s.allowedServiceAccountJWT = jwt s.replyRead = createReadServiceAccountFound(namespace, name, uid, overrideAnnotation) s.replyStatus = createTokenReviewFound(namespace, name, uid, jwt) } // Stop stops the running TestAPIServer. func (s *TestAPIServer) Stop() { s.srv.Close() if s.returnFunc != nil { s.returnFunc() s.returnFunc = nil } } // Addr returns the current base URL for the running webserver. func (s *TestAPIServer) Addr() string { return s.srv.URL } // CACert returns the pem-encoded CA certificate used by the HTTPS server. func (s *TestAPIServer) CACert() string { return s.caCert } var readServiceAccountPathRE = regexp.MustCompile("^/api/v1/namespaces/([^/]+)/serviceaccounts/([^/]+)$") func (s *TestAPIServer) ServeHTTP(w http.ResponseWriter, req *http.Request) { s.mu.Lock() defer s.mu.Unlock() w.Header().Set("content-type", "application/json") if req.URL.Path == "/apis/authentication.k8s.io/v1/tokenreviews" { s.handleTokenReview(w, req) return } if m := readServiceAccountPathRE.FindStringSubmatch(req.URL.Path); m != nil { namespace, err := url.QueryUnescape(m[1]) if err != nil { w.WriteHeader(http.StatusBadRequest) return } name, err := url.QueryUnescape(m[2]) if err != nil { w.WriteHeader(http.StatusBadRequest) return } s.handleReadServiceAccount(namespace, name, w, req) return } w.WriteHeader(http.StatusNotFound) } func writeJSON(w http.ResponseWriter, out interface{}) error { enc := json.NewEncoder(w) return enc.Encode(out) } func (s *TestAPIServer) handleTokenReview(w http.ResponseWriter, req *http.Request) { if req.Method != "POST" { w.WriteHeader(http.StatusMethodNotAllowed) return } if auth, anon := s.isAuthenticated(req); !auth { var out interface{} if anon { out = createTokenReviewForbidden_NoAuthz() } else { out = createTokenReviewForbidden("default", "fake-account") } w.WriteHeader(http.StatusForbidden) if err := writeJSON(w, out); err != nil { w.WriteHeader(http.StatusInternalServerError) } return } if req.Body == nil { w.WriteHeader(http.StatusBadRequest) return } defer req.Body.Close() b, err := ioutil.ReadAll(req.Body) if err != nil { w.WriteHeader(http.StatusInternalServerError) return } var trReq authv1.TokenReview if err := json.Unmarshal(b, &trReq); err != nil { w.WriteHeader(http.StatusInternalServerError) return } reviewingJWT := trReq.Spec.Token var out interface{} if s.replyStatus == nil || reviewingJWT != s.allowedServiceAccountJWT { out = createTokenReviewNotFound(reviewingJWT) } else { out = s.replyStatus } w.WriteHeader(http.StatusCreated) if err := writeJSON(w, out); err != nil { w.WriteHeader(http.StatusInternalServerError) return } } func (s *TestAPIServer) handleReadServiceAccount( namespace, name string, w http.ResponseWriter, req *http.Request, ) { if req.Method != "GET" { w.WriteHeader(http.StatusMethodNotAllowed) return } var out interface{} if auth, anon := s.isAuthenticated(req); !auth { if anon { out = createReadServiceAccountForbidden_NoAuthz() } else { out = createReadServiceAccountForbidden(namespace, name) } w.WriteHeader(http.StatusForbidden) } else if s.replyRead == nil { out = createReadServiceAccountNotFound(name) w.WriteHeader(http.StatusNotFound) } else if s.replyRead.Namespace != namespace || s.replyRead.Name != name { out = createReadServiceAccountNotFound(name) w.WriteHeader(http.StatusNotFound) } else { out = s.replyRead w.WriteHeader(http.StatusOK) } if err := writeJSON(w, out); err != nil { w.WriteHeader(http.StatusInternalServerError) return } } func (s *TestAPIServer) isAuthenticated(req *http.Request) (auth, anonymous bool) { authz := req.Header.Get("Authorization") if !strings.HasPrefix(authz, "Bearer ") { return false, true } jwt := strings.TrimPrefix(authz, "Bearer ") return s.authorizedJWT == jwt, false } func createTokenReviewForbidden_NoAuthz() *metav1.Status { /* STATUS: 403 { "kind": "Status", "apiVersion": "v1", "metadata": {}, "status": "Failure", "message": "tokenreviews.authentication.k8s.io is forbidden: User \"system:anonymous\" cannot create resource \"tokenreviews\" in API group \"authentication.k8s.io\" at the cluster scope", "reason": "Forbidden", "details": { "group": "authentication.k8s.io", "kind": "tokenreviews" }, "code": 403 } */ return createStatus( metav1.StatusFailure, "tokenreviews.authentication.k8s.io is forbidden: User \"system:anonymous\" cannot create resource \"tokenreviews\" in API group \"authentication.k8s.io\" in the cluster scope", metav1.StatusReasonForbidden, &metav1.StatusDetails{ Group: "authentication.k8s.io", Kind: "tokenreviews", }, 403, ) } func createTokenReviewForbidden(namespace, name string) *metav1.Status { /* STATUS: 403 { "kind": "Status", "apiVersion": "v1", "metadata": {}, "status": "Failure", "message": "tokenreviews.authentication.k8s.io is forbidden: User \"system:serviceaccount:default:admin\" cannot create resource \"tokenreviews\" in API group \"authentication.k8s.io\" at the cluster scope", "reason": "Forbidden", "details": { "group": "authentication.k8s.io", "kind": "tokenreviews" }, "code": 403 } */ return createStatus( metav1.StatusFailure, "tokenreviews.authentication.k8s.io is forbidden: User \"system:serviceaccount:"+namespace+":"+name+"\" cannot create resource \"tokenreviews\" in API group \"authentication.k8s.io\" in the cluster scope", metav1.StatusReasonForbidden, &metav1.StatusDetails{ Group: "authentication.k8s.io", Kind: "tokenreviews", }, 403, ) } func createTokenReviewNotFound(jwt string) *authv1.TokenReview { /* STATUS: 201 { "kind": "TokenReview", "apiVersion": "authentication.k8s.io/v1", "metadata": { "creationTimestamp": null }, "spec": { "token": "eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImZha2UtdG9rZW4tano2YnYiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC5uYW1lIjoiZmFrZSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6IjgxYTY1Mjg2LTU3YzEtMTFlOS1iYzJhLTQ4ZTZjOGI4ZWNiNSIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDpkZWZhdWx0OmZha2UifQ.DqjUXe34SzCP4NCwbhqV9EuksfzmTSLhJzkE_URyufeGJDn-Gw0_JS-_KmxZSdAO0XXNzB1tJNM1NCVW-V6YbThnPUw5WY4V2J6U1W72c2dzNBx_ipBxGBZ632ZnpViIRu6tL2guT36lWa8YnMDF_OY8sHhl_3kJ6MRxNxY41vAuf45mohi3gri46Kpzc3pf1g6PJ-0oogvUsZ2nBFv1mIdciGBV0zejMKc5Bnxur1L-hEQ9EgZrJ7o0yQRCWYgam_yo_M38EsB8b-suTzQJMA-pRgApOb9dHIV6YAE_b3g_pGkJjrPYzV4IJC1CiPfdz1SAjm7e0ARXtZmaoPltjQ" }, "status": { "user": {}, "error": "[invalid bearer token, Token has been invalidated]" } } */ return &authv1.TokenReview{ TypeMeta: metav1.TypeMeta{ Kind: "TokenReview", APIVersion: "authentication.k8s.io/v1", }, ObjectMeta: metav1.ObjectMeta{}, Spec: authv1.TokenReviewSpec{ Token: jwt, }, Status: authv1.TokenReviewStatus{ User: authv1.UserInfo{}, Error: "[invalid bearer token, Token has been invalidated]", }, } } func createTokenReviewFound(namespace, name, uid, jwt string) *authv1.TokenReview { /* STATUS: 201 { "kind": "TokenReview", "apiVersion": "authentication.k8s.io/v1", "metadata": { "creationTimestamp": null }, "spec": { "token": "eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJkZWZhdWx0Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZWNyZXQubmFtZSI6ImRlbW8tdG9rZW4tbTljdm4iLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC5uYW1lIjoiZGVtbyIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6IjlmZjUxZmY0LTU1N2UtMTFlOS05Njg3LTQ4ZTZjOGI4ZWNiNSIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDpkZWZhdWx0OmRlbW8ifQ.UJEphtrN261gy9WCl4ZKjm2PRDLDkc3Xg9VcDGfzyroOqFQ6sog5dVAb9voc5Nc0-H5b1yGwxDViEMucwKvZpA5pi7VEx_OskK-KTWXSmafM0Xg_AvzpU9Ed5TSRno-OhXaAraxdjXoC4myh1ay2DMeHUusJg_ibqcYJrWx-6MO1bH_ObORtAKhoST_8fzkqNAlZmsQ87FinQvYN5mzDXYukl-eeRdBgQUBkWvEb-Ju6cc0-QE4sUQ4IH_fs0fUyX_xc0om0SZGWLP909FTz4V8LxV8kr6L7irxROiS1jn3Fvyc9ur1PamVf3JOPPrOyfmKbaGRiWJM32b3buQw7cg" }, "status": { "authenticated": true, "user": { "username": "system:serviceaccount:default:demo", "uid": "9ff51ff4-557e-11e9-9687-48e6c8b8ecb5", "groups": [ "system:serviceaccounts", "system:serviceaccounts:default", "system:authenticated" ] } } } */ return &authv1.TokenReview{ TypeMeta: metav1.TypeMeta{ Kind: "TokenReview", APIVersion: "authentication.k8s.io/v1", }, ObjectMeta: metav1.ObjectMeta{}, Spec: authv1.TokenReviewSpec{ Token: jwt, }, Status: authv1.TokenReviewStatus{ Authenticated: true, User: authv1.UserInfo{ Username: "system:serviceaccount:" + namespace + ":" + name, UID: uid, Groups: []string{ "system:serviceaccounts", "system:serviceaccounts:default", "system:authenticated", }, }, }, } } func createReadServiceAccountForbidden(namespace, name string) *metav1.Status { /* STATUS: 403 { "kind": "Status", "apiVersion": "v1", "metadata": {}, "status": "Failure", "message": "serviceaccounts \"demo\" is forbidden: User \"system:serviceaccount:default:admin\" cannot get resource \"serviceaccounts\" in API group \"\" in the namespace \"default\"", "reason": "Forbidden", "details": { "name": "demo", "kind": "serviceaccounts" }, "code": 403 } */ return createStatus( metav1.StatusFailure, "serviceaccounts \""+name+"\" is forbidden: User \"system:serviceaccount:"+namespace+":"+name+"\" cannot get resource \"serviceaccounts\" in API group \"\" in the namespace \""+namespace+"\"", metav1.StatusReasonForbidden, &metav1.StatusDetails{ Kind: "serviceaccounts", Name: name, }, 403, ) } func createReadServiceAccountForbidden_NoAuthz() *metav1.Status { // missing bearer token header 403 /* { "kind": "Status", "apiVersion": "v1", "metadata": {}, "status": "Failure", "message": "serviceaccounts \"demo\" is forbidden: User \"system:anonymous\" cannot get resource \"serviceaccounts\" in API group \"\" in the namespace \"default\"", "reason": "Forbidden", "details": { "name": "demo", "kind": "serviceaccounts" }, "code": 403 } */ return createStatus( metav1.StatusFailure, "serviceaccounts \"PLACEHOLDER\" is forbidden: User \"system:anonymous\" cannot get resource \"serviceaccounts\" in API group \"\" in the namespace \"default\"", metav1.StatusReasonForbidden, &metav1.StatusDetails{ Kind: "serviceaccounts", Name: "PLACEHOLDER", }, 403, ) } func createReadServiceAccountNotFound(name string) *metav1.Status { /* STATUS: 404 { "kind": "Status", "apiVersion": "v1", "metadata": {}, "status": "Failure", "message": "serviceaccounts \"demo\" not found", "reason": "NotFound", "details": { "name": "demo", "kind": "serviceaccounts" }, "code": 404 } */ return createStatus( metav1.StatusFailure, "serviceaccounts \""+name+"\" not found", metav1.StatusReasonNotFound, &metav1.StatusDetails{ Kind: "serviceaccounts", Name: name, }, 404, ) } func createReadServiceAccountFound(namespace, name, uid, overrideAnnotation string) *corev1.ServiceAccount { /* STATUS: 200 { "kind": "ServiceAccount", "apiVersion": "v1", "metadata": { "name": "demo", "namespace": "default", "selfLink": "/api/v1/namespaces/default/serviceaccounts/demo", "uid": "9ff51ff4-557e-11e9-9687-48e6c8b8ecb5", "resourceVersion": "2101", "creationTimestamp": "2019-04-02T19:36:34Z", "annotations": { "consul.hashicorp.com/service-name": "actual", "kubectl.kubernetes.io/last-applied-configuration": "{\"apiVersion\":\"v1\",\"kind\":\"ServiceAccount\",\"metadata\":{\"annotations\":{\"consul.hashicorp.com/service-name\":\"actual\"},\"name\":\"demo\",\"namespace\":\"default\"}}\n" } }, "secrets": [ { "name": "demo-token-m9cvn" } ] } */ sa := &corev1.ServiceAccount{ TypeMeta: metav1.TypeMeta{ Kind: "ServiceAccount", APIVersion: "v1", }, ObjectMeta: metav1.ObjectMeta{ Name: name, Namespace: namespace, SelfLink: "/api/v1/namespaces/" + namespace + "/serviceaccounts/" + name, UID: types.UID(uid), ResourceVersion: "123", CreationTimestamp: metav1.Time{Time: time.Now()}, }, Secrets: []corev1.ObjectReference{ { Name: name + "-token-m9cvn", }, }, } if overrideAnnotation != "" { sa.ObjectMeta.Annotations = map[string]string{ "consul.hashicorp.com/service-name": overrideAnnotation, } } return sa } func createStatus(status, message string, reason metav1.StatusReason, details *metav1.StatusDetails, code int32) *metav1.Status { return &metav1.Status{ TypeMeta: metav1.TypeMeta{ Kind: "Status", APIVersion: "v1", }, ListMeta: metav1.ListMeta{}, Status: status, Message: message, Reason: reason, Details: details, Code: code, } } func httptestNewUnstartedServerWithPort(handler http.Handler, port int) *httptest.Server { if port == 0 { return httptest.NewUnstartedServer(handler) } addr := net.JoinHostPort("127.0.0.1", strconv.Itoa(port)) l, err := net.Listen("tcp", addr) if err != nil { panic(fmt.Sprintf("httptest: failed to listen on a port: %v", err)) } return &httptest.Server{ Listener: l, Config: &http.Server{Handler: handler}, } }