k8s.io/apiserver@v0.31.1/pkg/util/webhook/validation.go (about)

     1  /*
     2  Copyright 2018 The Kubernetes Authors.
     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 webhook
    18  
    19  import (
    20  	"fmt"
    21  	"net/url"
    22  	"strings"
    23  
    24  	"k8s.io/apimachinery/pkg/util/validation"
    25  	"k8s.io/apimachinery/pkg/util/validation/field"
    26  	"k8s.io/client-go/transport"
    27  )
    28  
    29  func ValidateCABundle(fldPath *field.Path, caBundle []byte) field.ErrorList {
    30  	var allErrors field.ErrorList
    31  	_, err := transport.TLSConfigFor(&transport.Config{TLS: transport.TLSConfig{CAData: caBundle}})
    32  	if err != nil {
    33  		allErrors = append(allErrors, field.Invalid(fldPath, caBundle, err.Error()))
    34  	}
    35  	return allErrors
    36  }
    37  
    38  // ValidateWebhookURL validates webhook's URL.
    39  func ValidateWebhookURL(fldPath *field.Path, URL string, forceHttps bool) field.ErrorList {
    40  	var allErrors field.ErrorList
    41  	const form = "; desired format: https://host[/path]"
    42  	if u, err := url.Parse(URL); err != nil {
    43  		allErrors = append(allErrors, field.Required(fldPath, "url must be a valid URL: "+err.Error()+form))
    44  	} else {
    45  		if forceHttps && u.Scheme != "https" {
    46  			allErrors = append(allErrors, field.Invalid(fldPath, u.Scheme, "'https' is the only allowed URL scheme"+form))
    47  		}
    48  		if len(u.Host) == 0 {
    49  			allErrors = append(allErrors, field.Invalid(fldPath, u.Host, "host must be specified"+form))
    50  		}
    51  		if u.User != nil {
    52  			allErrors = append(allErrors, field.Invalid(fldPath, u.User.String(), "user information is not permitted in the URL"))
    53  		}
    54  		if len(u.Fragment) != 0 {
    55  			allErrors = append(allErrors, field.Invalid(fldPath, u.Fragment, "fragments are not permitted in the URL"))
    56  		}
    57  		if len(u.RawQuery) != 0 {
    58  			allErrors = append(allErrors, field.Invalid(fldPath, u.RawQuery, "query parameters are not permitted in the URL"))
    59  		}
    60  	}
    61  	return allErrors
    62  }
    63  
    64  func ValidateWebhookService(fldPath *field.Path, namespace, name string, path *string, port int32) field.ErrorList {
    65  	var allErrors field.ErrorList
    66  
    67  	if len(name) == 0 {
    68  		allErrors = append(allErrors, field.Required(fldPath.Child("name"), "service name is required"))
    69  	}
    70  
    71  	if len(namespace) == 0 {
    72  		allErrors = append(allErrors, field.Required(fldPath.Child("namespace"), "service namespace is required"))
    73  	}
    74  
    75  	if errs := validation.IsValidPortNum(int(port)); errs != nil {
    76  		allErrors = append(allErrors, field.Invalid(fldPath.Child("port"), port, "port is not valid: "+strings.Join(errs, ", ")))
    77  	}
    78  
    79  	if path == nil {
    80  		return allErrors
    81  	}
    82  
    83  	// TODO: replace below with url.Parse + verifying that host is empty?
    84  
    85  	urlPath := *path
    86  	if urlPath == "/" || len(urlPath) == 0 {
    87  		return allErrors
    88  	}
    89  	if urlPath == "//" {
    90  		allErrors = append(allErrors, field.Invalid(fldPath.Child("path"), urlPath, "segment[0] may not be empty"))
    91  		return allErrors
    92  	}
    93  
    94  	if !strings.HasPrefix(urlPath, "/") {
    95  		allErrors = append(allErrors, field.Invalid(fldPath.Child("path"), urlPath, "must start with a '/'"))
    96  	}
    97  
    98  	urlPathToCheck := urlPath[1:]
    99  	if strings.HasSuffix(urlPathToCheck, "/") {
   100  		urlPathToCheck = urlPathToCheck[:len(urlPathToCheck)-1]
   101  	}
   102  	steps := strings.Split(urlPathToCheck, "/")
   103  	for i, step := range steps {
   104  		if len(step) == 0 {
   105  			allErrors = append(allErrors, field.Invalid(fldPath.Child("path"), urlPath, fmt.Sprintf("segment[%d] may not be empty", i)))
   106  			continue
   107  		}
   108  		failures := validation.IsDNS1123Subdomain(step)
   109  		for _, failure := range failures {
   110  			allErrors = append(allErrors, field.Invalid(fldPath.Child("path"), urlPath, fmt.Sprintf("segment[%d]: %v", i, failure)))
   111  		}
   112  	}
   113  
   114  	return allErrors
   115  }