Add support for HTTP basic auth to the kube-apiserver.

cmd/kube-apiserver/app/server.go

@@ -63,6 +63,7 @@ type APIServer struct {
 	CloudProvider              string
 	CloudConfigFile            string
 	EventTTL                   time.Duration
+	BasicAuthFile              string
 	ClientCAFile               string
 	TokenAuthFile              string
 	AuthorizationMode          string
@@ -155,6 +156,7 @@ func (s *APIServer) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&s.CloudProvider, "cloud-provider", s.CloudProvider, "The provider for cloud services.  Empty string for no provider.")
 	fs.StringVar(&s.CloudConfigFile, "cloud-config", s.CloudConfigFile, "The path to the cloud provider configuration file.  Empty string for no configuration file.")
 	fs.DurationVar(&s.EventTTL, "event-ttl", s.EventTTL, "Amount of time to retain events. Default 1 hour.")
+	fs.StringVar(&s.BasicAuthFile, "basic-auth-file", s.BasicAuthFile, "If set, the file that will be used to admit requests to the secure port of the API server via http basic authentication.")
 	fs.StringVar(&s.ClientCAFile, "client-ca-file", s.ClientCAFile, "If set, any request presenting a client certificate signed by one of the authorities in the client-ca-file is authenticated with an identity corresponding to the CommonName of the client certificate.")
 	fs.StringVar(&s.TokenAuthFile, "token-auth-file", s.TokenAuthFile, "If set, the file that will be used to secure the secure port of the API server via token authentication.")
 	fs.StringVar(&s.AuthorizationMode, "authorization-mode", s.AuthorizationMode, "Selects how to do authorization on the secure port.  One of: "+strings.Join(apiserver.AuthorizationModeChoices, ","))
@@ -242,7 +244,7 @@ func (s *APIServer) Run(_ []string) error {
 
 	n := net.IPNet(s.PortalNet)
 
-	authenticator, err := apiserver.NewAuthenticator(s.ClientCAFile, s.TokenAuthFile)
+	authenticator, err := apiserver.NewAuthenticator(s.BasicAuthFile, s.ClientCAFile, s.TokenAuthFile)
 	if err != nil {
 		glog.Fatalf("Invalid Authentication Config: %v", err)
 	}

docs/authentication.md

 # Authentication Plugins
 
-Kubernetes uses tokens or client certificates to authenticate users for API calls.
+Kubernetes uses client certificates, tokens, or http basic auth to authenticate users for API calls.
 
 Client certificate authentication is enabled by passing the `--client_ca_file=SOMEFILE`
 option to apiserver. The referenced file must contain one or more certificates authorities
@@ -16,6 +16,16 @@ be short-lived, and to be generated as needed rather than stored in a file.
 The token file format is implemented in `plugin/pkg/auth/authenticator/token/tokenfile/...`
 and is a csv file with 3 columns: token, user name, user uid.
 
+Basic authentication is enabled by passing the `--basic_auth_file=SOMEFILE`
+option to apiserver. Currently, the basic auth credentials last indefinitely,
+and the password cannot be changed without restarting apiserver. Note that basic
+authentication is currently supported for convenience while we finish making the
+more secure modes described above easier to use.
+
+The basic auth file format is implemented in `plugin/pkg/auth/authenticator/password/passwordfile/...`
+and is a csv file with 3 columns: password, user name, user id.
+
+
 ## Plugin Development
 
 We plan for the Kubernetes API server to issue tokens

pkg/apiserver/authn.go

@@ -20,14 +20,24 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/auth/authenticator"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/auth/authenticator/bearertoken"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
+	"github.com/GoogleCloudPlatform/kubernetes/plugin/pkg/auth/authenticator/password/passwordfile"
+	"github.com/GoogleCloudPlatform/kubernetes/plugin/pkg/auth/authenticator/request/basicauth"
 	"github.com/GoogleCloudPlatform/kubernetes/plugin/pkg/auth/authenticator/request/union"
 	"github.com/GoogleCloudPlatform/kubernetes/plugin/pkg/auth/authenticator/request/x509"
 	"github.com/GoogleCloudPlatform/kubernetes/plugin/pkg/auth/authenticator/token/tokenfile"
 )
 
 // NewAuthenticator returns an authenticator.Request or an error
-func NewAuthenticator(clientCAFile string, tokenFile string) (authenticator.Request, error) {
-	authenticators := []authenticator.Request{}
+func NewAuthenticator(basicAuthFile, clientCAFile, tokenFile string) (authenticator.Request, error) {
+	var authenticators []authenticator.Request
+
+	if len(basicAuthFile) > 0 {
+		basicAuth, err := newAuthenticatorFromBasicAuthFile(basicAuthFile)
+		if err != nil {
+			return nil, err
+		}
+		authenticators = append(authenticators, basicAuth)
+	}
 
 	if len(clientCAFile) > 0 {
 		certAuth, err := newAuthenticatorFromClientCAFile(clientCAFile)
@@ -45,14 +55,24 @@ func NewAuthenticator(clientCAFile string, tokenFile string) (authenticator.Requ
 		authenticators = append(authenticators, tokenAuth)
 	}
 
-	if len(authenticators) == 0 {
+	switch len(authenticators) {
+	case 0:
 		return nil, nil
-	}
-	if len(authenticators) == 1 {
+	case 1:
 		return authenticators[0], nil
+	default:
+		return union.New(authenticators...), nil
+	}
+}
+
+// newAuthenticatorFromBasicAuthFile returns an authenticator.Request or an error
+func newAuthenticatorFromBasicAuthFile(basicAuthFile string) (authenticator.Request, error) {
+	basicAuthenticator, err := passwordfile.NewCSV(basicAuthFile)
+	if err != nil {
+		return nil, err
 	}
-	return union.New(authenticators...), nil
 
+	return basicauth.New(basicAuthenticator), nil
 }
 
 // newAuthenticatorFromTokenFile returns an authenticator.Request or an error

plugin/pkg/auth/authenticator/password/passwordfile/passwordfile.go

+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+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 passwordfile
+
+import (
+	"encoding/csv"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/auth/user"
+)
+
+type PasswordAuthenticator struct {
+	users map[string]*userPasswordInfo
+}
+
+type userPasswordInfo struct {
+	info     *user.DefaultInfo
+	password string
+}
+
+// NewCSV returns a PasswordAuthenticator, populated from a CSV file.
+// The CSV file must contain records in the format "password,username,useruid"
+func NewCSV(path string) (*PasswordAuthenticator, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	users := make(map[string]*userPasswordInfo)
+	reader := csv.NewReader(file)
+	for {
+		record, err := reader.Read()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, err
+		}
+		if len(record) < 3 {
+			return nil, fmt.Errorf("password file '%s' must have at least 3 columns (password, user name, user uid), found %d", path, len(record))
+		}
+		obj := &userPasswordInfo{
+			info:     &user.DefaultInfo{Name: record[1], UID: record[2]},
+			password: record[0],
+		}
+		users[obj.info.Name] = obj
+	}
+
+	return &PasswordAuthenticator{users}, nil
+}
+
+func (a *PasswordAuthenticator) AuthenticatePassword(username, password string) (user.Info, bool, error) {
+	user, ok := a.users[username]
+	if !ok {
+		return nil, false, nil
+	}
+	if user.password != password {
+		return nil, false, nil
+	}
+	return user.info, true, nil
+}

plugin/pkg/auth/authenticator/password/passwordfile/passwordfile_test.go

+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+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 passwordfile
+
+import (
+	"io/ioutil"
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/auth/user"
+)
+
+func TestPasswordFile(t *testing.T) {
+	auth, err := newWithContents(t, `
+password1,user1,uid1
+password2,user2,uid2
+`)
+	if err != nil {
+		t.Fatalf("unable to read passwordfile: %v", err)
+	}
+
+	testCases := []struct {
+		Username string
+		Password string
+		User     *user.DefaultInfo
+		Ok       bool
+		Err      bool
+	}{
+		{
+			Username: "user1",
+			Password: "password1",
+			User:     &user.DefaultInfo{Name: "user1", UID: "uid1"},
+			Ok:       true,
+		},
+		{
+			Username: "user2",
+			Password: "password2",
+			User:     &user.DefaultInfo{Name: "user2", UID: "uid2"},
+			Ok:       true,
+		},
+		{
+			Username: "user1",
+			Password: "password2",
+		},
+		{
+			Username: "user2",
+			Password: "password1",
+		},
+		{
+			Username: "user3",
+			Password: "password3",
+		},
+		{
+			Username: "user4",
+			Password: "password4",
+		},
+	}
+	for i, testCase := range testCases {
+		user, ok, err := auth.AuthenticatePassword(testCase.Username, testCase.Password)
+		if err != nil {
+			t.Errorf("%d: unexpected error: %v", i, err)
+		}
+		if testCase.User == nil {
+			if user != nil {
+				t.Errorf("%d: unexpected non-nil user %#v", i, user)
+			}
+		} else if !reflect.DeepEqual(testCase.User, user) {
+			t.Errorf("%d: expected user %#v, got %#v", i, testCase.User, user)
+		}
+		if testCase.Ok != ok {
+			t.Errorf("%d: expected auth %v, got %v", i, testCase.Ok, ok)
+		}
+	}
+}
+
+func TestBadPasswordFile(t *testing.T) {
+	if _, err := newWithContents(t, `
+password1,user1,uid1
+password2,user2,uid2
+password3,user3
+password4
+`); err == nil {
+		t.Fatalf("unexpected non error")
+	}
+}
+
+func TestInsufficientColumnsPasswordFile(t *testing.T) {
+	if _, err := newWithContents(t, "password4\n"); err == nil {
+		t.Fatalf("unexpected non error")
+	}
+}
+
+func newWithContents(t *testing.T, contents string) (auth *PasswordAuthenticator, err error) {
+	f, err := ioutil.TempFile("", "passwordfile_test")
+	if err != nil {
+		t.Fatalf("unexpected error creating passwordfile: %v", err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+
+	if err := ioutil.WriteFile(f.Name(), []byte(contents), 0700); err != nil {
+		t.Fatalf("unexpected error writing passwordfile: %v", err)
+	}
+
+	return NewCSV(f.Name())
+}