Basic Auth etcd mode to use username by default (#472)

* basic auth etcd mode to use username if present

* rename DefaultUsername() to Username()

pkg/filter/validator/basicauth.go

@@ -54,7 +54,10 @@ type (
 		// key: /custom-data/{etcdPrefix}/{$key}
 		// value:
 		//   key: "$key"
+		//   username: "$username" # optional
 		//   password: "$password"
+		// Username and password are used for Basic Authentication. If "username" is empty, the value of "key"
+		// entry is used as username for Basic Auth.
 		EtcdPrefix string `yaml:"etcdPrefix" jsonschema:"omitempty"`
 	}
 
@@ -89,16 +92,31 @@ type (
 		authorizedUsersCache AuthorizedUsersCache
 	}
 
-	credentials struct {
-		Key      string `yaml:"key" jsonschema:"omitempty"`
-		Password string `yaml:"password" jsonschema:"omitempty"`
+	// etcdCredentials defines the format for credentials in etcd
+	etcdCredentials struct {
+		Key  string `yaml:"key" jsonschema:"omitempty"`
+		User string `yaml:"username" jsonschema:"omitempty"`
+		Pass string `yaml:"password" jsonschema:"required"`
 	}
 )
 
 const (
 	customDataPrefix = "/custom-data/"
 )
 
+// Username uses username if present, otherwise key
+func (cred *etcdCredentials) Username() string {
+	if cred.User != "" {
+		return cred.User
+	}
+	return cred.Key
+}
+
+// Password returns password.
+func (cred *etcdCredentials) Password() string {
+	return cred.Pass
+}
+
 func parseCredentials(creds string) (string, string, error) {
 	parts := strings.Split(creds, ":")
 	if len(parts) < 2 {
@@ -213,19 +231,20 @@ func newEtcdUserCache(cluster cluster.Cluster, etcdPrefix string) *etcdUserCache
 func kvsToReader(kvs map[string]string) io.Reader {
 	pwStrSlice := make([]string, 0, len(kvs))
 	for _, item := range kvs {
-		creds := &credentials{}
+		creds := &etcdCredentials{}
 		err := yaml.Unmarshal([]byte(item), creds)
 		if err != nil {
 			logger.Errorf(err.Error())
 			continue
 		}
-		if creds.Key == "" || creds.Password == "" {
+		if creds.Username() == "" || creds.Password() == "" {
 			logger.Errorf(
-				"Parsing credential updates failed. Make sure that credentials contains 'key' and 'password' entries.",
+				"Parsing credential updates failed. " +
+					"Make sure that credentials contains 'key' or 'password' entry for password and 'password' entries.",
 			)
 			continue
 		}
-		pwStrSlice = append(pwStrSlice, creds.Key+":"+creds.Password)
+		pwStrSlice = append(pwStrSlice, creds.Username()+":"+creds.Password())
 	}
 	if len(pwStrSlice) == 0 {
 		// no credentials found, let's return empty reader

pkg/filter/validator/validator_test.go

@@ -377,6 +377,17 @@ basicAuth:
 		expectedValid := []bool{true, true, false}
 
 		v = createValidator(yamlSpec, nil, nil)
+
+		t.Run("invalid headers", func(t *testing.T) {
+			ctx, header := prepareCtxAndHeader()
+			b64creds := base64.StdEncoding.EncodeToString([]byte(userIds[0])) // missing : and pw
+			header.Set("Authorization", "Basic "+b64creds)
+			result := v.Handle(ctx)
+			if result != resultInvalid {
+				t.Errorf("should be bad format")
+			}
+		})
+
 		for i := 0; i < 3; i++ {
 			ctx, header := prepareCtxAndHeader()
 			b64creds := base64.StdEncoding.EncodeToString([]byte(userIds[i] + ":" + passwords[i]))
@@ -428,6 +439,15 @@ basicAuth:
 		}
 	})
 
+	t.Run("dummy etcd", func(t *testing.T) {
+		userCache := &etcdUserCache{prefix: ""} // should now skip cluster ops
+		userCache.WatchChanges()
+		if userCache.Match("doge", "dogepw") {
+			t.Errorf("should not match")
+		}
+		userCache.Close()
+	})
+
 	t.Run("credentials from etcd", func(t *testing.T) {
 		etcdDirName, err := ioutil.TempDir("", "etcd-validator-test")
 		check(err)
@@ -442,11 +462,14 @@ basicAuth:
 			t.Errorf("newEtcdUserCache failed")
 		}
 
-		pwToYaml := func(user string, pw string) string {
-			return fmt.Sprintf("key: %s\npassword: %s", user, pw)
+		pwToYaml := func(key string, user string, pw string) string {
+			if user != "" {
+				return fmt.Sprintf("username: %s\npassword: %s", user, pw)
+			}
+			return fmt.Sprintf("key: %s\npassword: %s", key, pw)
 		}
-		clusterInstance.Put("/custom-data/credentials/1", pwToYaml(userIds[0], encryptedPasswords[0]))
-		clusterInstance.Put("/custom-data/credentials/2", pwToYaml(userIds[2], encryptedPasswords[2]))
+		clusterInstance.Put("/custom-data/credentials/1", pwToYaml(userIds[0], "", encryptedPasswords[0]))
+		clusterInstance.Put("/custom-data/credentials/2", pwToYaml("", userIds[2], encryptedPasswords[2]))
 
 		var mockMap sync.Map
 		supervisor := supervisor.NewMock(