github.com/gravitational/teleport/api@v0.0.0-20240507183017-3110591cbafc/utils/cluster.go (about)

     1  /*
     2  Copyright 2021 Gravitational, Inc.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package utils
    18  
    19  import (
    20  	"encoding/hex"
    21  	"fmt"
    22  	"strings"
    23  
    24  	"github.com/gravitational/trace"
    25  
    26  	"github.com/gravitational/teleport/api/constants"
    27  )
    28  
    29  // EncodeClusterName encodes cluster name in the SNI hostname
    30  func EncodeClusterName(clusterName string) string {
    31  	// hex is used to hide "." that will prevent wildcard *. entry to match
    32  	return fmt.Sprintf("%v.%v", hex.EncodeToString([]byte(clusterName)), constants.APIDomain)
    33  }
    34  
    35  // DecodeClusterName decodes cluster name, returns NotFound
    36  // if no cluster name is encoded (empty subdomain),
    37  // so servers can detect cases when no server name passed
    38  // returns BadParameter if encoding does not match
    39  func DecodeClusterName(serverName string) (string, error) {
    40  	if serverName == constants.APIDomain {
    41  		return "", trace.NotFound("no cluster name is encoded")
    42  	}
    43  	const suffix = "." + constants.APIDomain
    44  	if !strings.HasSuffix(serverName, suffix) {
    45  		return "", trace.NotFound("no cluster name is encoded")
    46  	}
    47  	clusterName := strings.TrimSuffix(serverName, suffix)
    48  
    49  	decoded, err := hex.DecodeString(clusterName)
    50  	if err != nil {
    51  		return "", trace.BadParameter("failed to decode cluster name: %v", err)
    52  	}
    53  	return string(decoded), nil
    54  }