kubernetes: enable azure auth

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>
2025-07-09 21:17:09 +08:00 · 2022-07-31 14:12:33 +02:00
parent 19641ec8ca
commit dfc1b361a9
94 changed files with 15370 additions and 1 deletions
--- a/vendor/k8s.io/client-go/plugin/pkg/client/auth/azure/README.md
+++ b/vendor/k8s.io/client-go/plugin/pkg/client/auth/azure/README.md
@ -0,0 +1,56 @@
+# Azure Active Directory plugin for client authentication
+
+This plugin provides an integration with Azure Active Directory device flow. If no tokens are present in the kubectl configuration, it will prompt a device code which can be used to login in a browser. After login it will automatically fetch the tokens and store them in the kubectl configuration. In addition it will refresh and update the tokens in the configuration when expired.
+
+## Usage
+
+1. Create an Azure Active Directory *Web App / API* application for `apiserver` following these [instructions](https://docs.microsoft.com/en-us/azure/active-directory/active-directory-app-registration). The callback URL does not matter (just cannot be empty).
+
+2. Create a second Azure Active Directory native application for `kubectl`. The callback URL does not matter (just cannot be empty).
+
+3. On `kubectl` application's configuration page in Azure portal grant permissions to `apiserver` application by clicking on *Required Permissions*, click the *Add* button and search for the apiserver application created in step 1. Select "Access apiserver" under the *DELEGATED PERMISSIONS*. Once added click the *Grant Permissions* button to apply the changes.
+
+4. Configure the `apiserver` to use the Azure Active Directory as an OIDC provider with following options
+
+   ```
+   --oidc-client-id="spn:APISERVER_APPLICATION_ID" \
+   --oidc-issuer-url="https://sts.windows.net/TENANT_ID/"
+   --oidc-username-claim="sub"
+   ```
+
+   * Replace the `APISERVER_APPLICATION_ID` with the application ID of `apiserver` application
+   * Replace `TENANT_ID` with your tenant ID.
+   * For a list of alternative username claims that are supported by the OIDC issuer check the JSON response at `https://sts.windows.net/TENANT_ID/.well-known/openid-configuration`.
+
+5. Configure `kubectl` to use the `azure` authentication provider
+
+   ```
+   kubectl config set-credentials "USER_NAME" --auth-provider=azure \
+     --auth-provider-arg=environment=AzurePublicCloud \
+     --auth-provider-arg=client-id=APPLICATION_ID \
+     --auth-provider-arg=tenant-id=TENANT_ID \
+     --auth-provider-arg=apiserver-id=APISERVER_APPLICATION_ID
+   ```
+
+   * Supported environments: `AzurePublicCloud`, `AzureUSGovernmentCloud`, `AzureChinaCloud`, `AzureGermanCloud`
+   * Replace `USER_NAME` and `TENANT_ID` with your user name and tenant ID
+   * Replace `APPLICATION_ID` with the application ID of your`kubectl` application ID
+   * Replace `APISERVER_APPLICATION_ID` with the application ID of your `apiserver` application ID
+   * Be sure to also (create and) select a context that uses above user
+
+6. (Optionally) the AAD token has `aud` claim with `spn:` prefix. To omit that, add following auth configuration:
+
+   ```
+     --auth-provider-arg=config-mode="1"
+   ```
+
+ 7. The access token is acquired when first `kubectl` command is executed
+
+   ```
+   kubectl get pods
+
+   To sign in, use a web browser to open the page https://aka.ms/devicelogin and enter the code DEC7D48GA to authenticate.
+   ```
+
+   * After signing in a web browser, the token is stored in the configuration, and it will be reused when executing further commands.
+   * The resulting username in Kubernetes depends on your [configuration of the `--oidc-username-claim` and `--oidc-username-prefix` flags on the API server](https://kubernetes.io/docs/admin/authentication/#configuring-the-api-server). If you are using any authorization method you need to give permissions to that user, e.g. by binding the user to a role in the case of RBAC.
--- a/vendor/k8s.io/client-go/plugin/pkg/client/auth/azure/azure.go
+++ b/vendor/k8s.io/client-go/plugin/pkg/client/auth/azure/azure.go
@ -0,0 +1,478 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+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 azure
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"os"
+	"strconv"
+	"sync"
+
+	"github.com/Azure/go-autorest/autorest"
+	"github.com/Azure/go-autorest/autorest/adal"
+	"github.com/Azure/go-autorest/autorest/azure"
+	"k8s.io/klog/v2"
+
+	"k8s.io/apimachinery/pkg/util/net"
+	restclient "k8s.io/client-go/rest"
+)
+
+type configMode int
+
+const (
+	azureTokenKey = "azureTokenKey"
+	tokenType     = "Bearer"
+	authHeader    = "Authorization"
+
+	cfgClientID     = "client-id"
+	cfgTenantID     = "tenant-id"
+	cfgAccessToken  = "access-token"
+	cfgRefreshToken = "refresh-token"
+	cfgExpiresIn    = "expires-in"
+	cfgExpiresOn    = "expires-on"
+	cfgEnvironment  = "environment"
+	cfgApiserverID  = "apiserver-id"
+	cfgConfigMode   = "config-mode"
+
+	configModeDefault       configMode = 0
+	configModeOmitSPNPrefix configMode = 1
+)
+
+func init() {
+	if err := restclient.RegisterAuthProviderPlugin("azure", newAzureAuthProvider); err != nil {
+		klog.Fatalf("Failed to register azure auth plugin: %v", err)
+	}
+}
+
+var cache = newAzureTokenCache()
+
+type azureTokenCache struct {
+	lock  sync.Mutex
+	cache map[string]*azureToken
+}
+
+func newAzureTokenCache() *azureTokenCache {
+	return &azureTokenCache{cache: make(map[string]*azureToken)}
+}
+
+func (c *azureTokenCache) getToken(tokenKey string) *azureToken {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	return c.cache[tokenKey]
+}
+
+func (c *azureTokenCache) setToken(tokenKey string, token *azureToken) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	c.cache[tokenKey] = token
+}
+
+var warnOnce sync.Once
+
+func newAzureAuthProvider(_ string, cfg map[string]string, persister restclient.AuthProviderConfigPersister) (restclient.AuthProvider, error) {
+	// deprecated in v1.22, remove in v1.25
+	// this should be updated to use klog.Warningf in v1.24 to more actively warn consumers
+	warnOnce.Do(func() {
+		klog.V(1).Infof(`WARNING: the azure auth plugin is deprecated in v1.22+, unavailable in v1.25+; use https://github.com/Azure/kubelogin instead.
+To learn more, consult https://kubernetes.io/docs/reference/access-authn-authz/authentication/#client-go-credential-plugins`)
+	})
+
+	var (
+		ts          tokenSource
+		environment azure.Environment
+		err         error
+		mode        configMode
+	)
+
+	environment, err = azure.EnvironmentFromName(cfg[cfgEnvironment])
+	if err != nil {
+		environment = azure.PublicCloud
+	}
+
+	mode = configModeDefault
+	if cfg[cfgConfigMode] != "" {
+		configModeInt, err := strconv.Atoi(cfg[cfgConfigMode])
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse %s, error: %s", cfgConfigMode, err)
+		}
+		mode = configMode(configModeInt)
+		switch mode {
+		case configModeOmitSPNPrefix:
+		case configModeDefault:
+		default:
+			return nil, fmt.Errorf("%s:%s is not a valid mode", cfgConfigMode, cfg[cfgConfigMode])
+		}
+	}
+	ts, err = newAzureTokenSourceDeviceCode(environment, cfg[cfgClientID], cfg[cfgTenantID], cfg[cfgApiserverID], mode)
+	if err != nil {
+		return nil, fmt.Errorf("creating a new azure token source for device code authentication: %v", err)
+	}
+	cacheSource := newAzureTokenSource(ts, cache, cfg, mode, persister)
+
+	return &azureAuthProvider{
+		tokenSource: cacheSource,
+	}, nil
+}
+
+type azureAuthProvider struct {
+	tokenSource tokenSource
+}
+
+func (p *azureAuthProvider) Login() error {
+	return errors.New("not yet implemented")
+}
+
+func (p *azureAuthProvider) WrapTransport(rt http.RoundTripper) http.RoundTripper {
+	return &azureRoundTripper{
+		tokenSource:  p.tokenSource,
+		roundTripper: rt,
+	}
+}
+
+type azureRoundTripper struct {
+	tokenSource  tokenSource
+	roundTripper http.RoundTripper
+}
+
+var _ net.RoundTripperWrapper = &azureRoundTripper{}
+
+func (r *azureRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	if len(req.Header.Get(authHeader)) != 0 {
+		return r.roundTripper.RoundTrip(req)
+	}
+
+	token, err := r.tokenSource.Token()
+	if err != nil {
+		klog.Errorf("Failed to acquire a token: %v", err)
+		return nil, fmt.Errorf("acquiring a token for authorization header: %v", err)
+	}
+
+	// clone the request in order to avoid modifying the headers of the original request
+	req2 := new(http.Request)
+	*req2 = *req
+	req2.Header = make(http.Header, len(req.Header))
+	for k, s := range req.Header {
+		req2.Header[k] = append([]string(nil), s...)
+	}
+
+	req2.Header.Set(authHeader, fmt.Sprintf("%s %s", tokenType, token.token.AccessToken))
+
+	return r.roundTripper.RoundTrip(req2)
+}
+
+func (r *azureRoundTripper) WrappedRoundTripper() http.RoundTripper { return r.roundTripper }
+
+type azureToken struct {
+	token       adal.Token
+	environment string
+	clientID    string
+	tenantID    string
+	apiserverID string
+}
+
+type tokenSource interface {
+	Token() (*azureToken, error)
+	Refresh(*azureToken) (*azureToken, error)
+}
+
+type azureTokenSource struct {
+	source     tokenSource
+	cache      *azureTokenCache
+	lock       sync.Mutex
+	configMode configMode
+	cfg        map[string]string
+	persister  restclient.AuthProviderConfigPersister
+}
+
+func newAzureTokenSource(source tokenSource, cache *azureTokenCache, cfg map[string]string, configMode configMode, persister restclient.AuthProviderConfigPersister) tokenSource {
+	return &azureTokenSource{
+		source:     source,
+		cache:      cache,
+		cfg:        cfg,
+		persister:  persister,
+		configMode: configMode,
+	}
+}
+
+// Token fetches a token from the cache of configuration if present otherwise
+// acquires a new token from the configured source. Automatically refreshes
+// the token if expired.
+func (ts *azureTokenSource) Token() (*azureToken, error) {
+	ts.lock.Lock()
+	defer ts.lock.Unlock()
+
+	var err error
+	token := ts.cache.getToken(azureTokenKey)
+
+	if token != nil && !token.token.IsExpired() {
+		return token, nil
+	}
+
+	// retrieve from config if no cache
+	if token == nil {
+		tokenFromCfg, err := ts.retrieveTokenFromCfg()
+
+		if err == nil {
+			token = tokenFromCfg
+		}
+	}
+
+	if token != nil {
+		// cache and return if the token is as good
+		// avoids frequent persistor calls
+		if !token.token.IsExpired() {
+			ts.cache.setToken(azureTokenKey, token)
+			return token, nil
+		}
+
+		klog.V(4).Info("Refreshing token.")
+		tokenFromRefresh, err := ts.Refresh(token)
+		switch {
+		case err == nil:
+			token = tokenFromRefresh
+		case autorest.IsTokenRefreshError(err):
+			klog.V(4).Infof("Failed to refresh expired token, proceed to auth: %v", err)
+			// reset token to nil so that the token source will be used to acquire new
+			token = nil
+		default:
+			return nil, fmt.Errorf("unexpected error when refreshing token: %v", err)
+		}
+	}
+
+	if token == nil {
+		tokenFromSource, err := ts.source.Token()
+		if err != nil {
+			return nil, fmt.Errorf("failed acquiring new token: %v", err)
+		}
+		token = tokenFromSource
+	}
+
+	// sanity check
+	if token == nil {
+		return nil, fmt.Errorf("unable to acquire token")
+	}
+
+	// corner condition, newly got token is valid but expired
+	if token.token.IsExpired() {
+		return nil, fmt.Errorf("newly acquired token is expired")
+	}
+
+	err = ts.storeTokenInCfg(token)
+	if err != nil {
+		return nil, fmt.Errorf("storing the refreshed token in configuration: %v", err)
+	}
+	ts.cache.setToken(azureTokenKey, token)
+
+	return token, nil
+}
+
+func (ts *azureTokenSource) retrieveTokenFromCfg() (*azureToken, error) {
+	accessToken := ts.cfg[cfgAccessToken]
+	if accessToken == "" {
+		return nil, fmt.Errorf("no access token in cfg: %s", cfgAccessToken)
+	}
+	refreshToken := ts.cfg[cfgRefreshToken]
+	if refreshToken == "" {
+		return nil, fmt.Errorf("no refresh token in cfg: %s", cfgRefreshToken)
+	}
+	environment := ts.cfg[cfgEnvironment]
+	if environment == "" {
+		return nil, fmt.Errorf("no environment in cfg: %s", cfgEnvironment)
+	}
+	clientID := ts.cfg[cfgClientID]
+	if clientID == "" {
+		return nil, fmt.Errorf("no client ID in cfg: %s", cfgClientID)
+	}
+	tenantID := ts.cfg[cfgTenantID]
+	if tenantID == "" {
+		return nil, fmt.Errorf("no tenant ID in cfg: %s", cfgTenantID)
+	}
+	resourceID := ts.cfg[cfgApiserverID]
+	if resourceID == "" {
+		return nil, fmt.Errorf("no apiserver ID in cfg: %s", cfgApiserverID)
+	}
+	expiresIn := ts.cfg[cfgExpiresIn]
+	if expiresIn == "" {
+		return nil, fmt.Errorf("no expiresIn in cfg: %s", cfgExpiresIn)
+	}
+	expiresOn := ts.cfg[cfgExpiresOn]
+	if expiresOn == "" {
+		return nil, fmt.Errorf("no expiresOn in cfg: %s", cfgExpiresOn)
+	}
+	tokenAudience := resourceID
+	if ts.configMode == configModeDefault {
+		tokenAudience = fmt.Sprintf("spn:%s", resourceID)
+	}
+
+	return &azureToken{
+		token: adal.Token{
+			AccessToken:  accessToken,
+			RefreshToken: refreshToken,
+			ExpiresIn:    json.Number(expiresIn),
+			ExpiresOn:    json.Number(expiresOn),
+			NotBefore:    json.Number(expiresOn),
+			Resource:     tokenAudience,
+			Type:         tokenType,
+		},
+		environment: environment,
+		clientID:    clientID,
+		tenantID:    tenantID,
+		apiserverID: resourceID,
+	}, nil
+}
+
+func (ts *azureTokenSource) storeTokenInCfg(token *azureToken) error {
+	newCfg := make(map[string]string)
+	newCfg[cfgAccessToken] = token.token.AccessToken
+	newCfg[cfgRefreshToken] = token.token.RefreshToken
+	newCfg[cfgEnvironment] = token.environment
+	newCfg[cfgClientID] = token.clientID
+	newCfg[cfgTenantID] = token.tenantID
+	newCfg[cfgApiserverID] = token.apiserverID
+	newCfg[cfgExpiresIn] = string(token.token.ExpiresIn)
+	newCfg[cfgExpiresOn] = string(token.token.ExpiresOn)
+	newCfg[cfgConfigMode] = strconv.Itoa(int(ts.configMode))
+
+	err := ts.persister.Persist(newCfg)
+	if err != nil {
+		return fmt.Errorf("persisting the configuration: %v", err)
+	}
+	ts.cfg = newCfg
+	return nil
+}
+
+func (ts *azureTokenSource) Refresh(token *azureToken) (*azureToken, error) {
+	return ts.source.Refresh(token)
+}
+
+// refresh outdated token with adal.
+func (ts *azureTokenSourceDeviceCode) Refresh(token *azureToken) (*azureToken, error) {
+	env, err := azure.EnvironmentFromName(token.environment)
+	if err != nil {
+		return nil, err
+	}
+
+	var oauthConfig *adal.OAuthConfig
+	if ts.configMode == configModeOmitSPNPrefix {
+		oauthConfig, err = adal.NewOAuthConfigWithAPIVersion(env.ActiveDirectoryEndpoint, token.tenantID, nil)
+		if err != nil {
+			return nil, fmt.Errorf("building the OAuth configuration without api-version for token refresh: %v", err)
+		}
+	} else {
+		oauthConfig, err = adal.NewOAuthConfig(env.ActiveDirectoryEndpoint, token.tenantID)
+		if err != nil {
+			return nil, fmt.Errorf("building the OAuth configuration for token refresh: %v", err)
+		}
+	}
+
+	callback := func(t adal.Token) error {
+		return nil
+	}
+	spt, err := adal.NewServicePrincipalTokenFromManualToken(
+		*oauthConfig,
+		token.clientID,
+		token.apiserverID,
+		token.token,
+		callback)
+	if err != nil {
+		return nil, fmt.Errorf("creating new service principal for token refresh: %v", err)
+	}
+
+	if err := spt.Refresh(); err != nil {
+		// Caller expects IsTokenRefreshError(err) to trigger prompt.
+		return nil, fmt.Errorf("refreshing token: %w", err)
+	}
+
+	return &azureToken{
+		token:       spt.Token(),
+		environment: token.environment,
+		clientID:    token.clientID,
+		tenantID:    token.tenantID,
+		apiserverID: token.apiserverID,
+	}, nil
+}
+
+type azureTokenSourceDeviceCode struct {
+	environment azure.Environment
+	clientID    string
+	tenantID    string
+	apiserverID string
+	configMode  configMode
+}
+
+func newAzureTokenSourceDeviceCode(environment azure.Environment, clientID string, tenantID string, apiserverID string, configMode configMode) (tokenSource, error) {
+	if clientID == "" {
+		return nil, errors.New("client-id is empty")
+	}
+	if tenantID == "" {
+		return nil, errors.New("tenant-id is empty")
+	}
+	if apiserverID == "" {
+		return nil, errors.New("apiserver-id is empty")
+	}
+	return &azureTokenSourceDeviceCode{
+		environment: environment,
+		clientID:    clientID,
+		tenantID:    tenantID,
+		apiserverID: apiserverID,
+		configMode:  configMode,
+	}, nil
+}
+
+func (ts *azureTokenSourceDeviceCode) Token() (*azureToken, error) {
+	var (
+		oauthConfig *adal.OAuthConfig
+		err         error
+	)
+	if ts.configMode == configModeOmitSPNPrefix {
+		oauthConfig, err = adal.NewOAuthConfigWithAPIVersion(ts.environment.ActiveDirectoryEndpoint, ts.tenantID, nil)
+		if err != nil {
+			return nil, fmt.Errorf("building the OAuth configuration without api-version for device code authentication: %v", err)
+		}
+	} else {
+		oauthConfig, err = adal.NewOAuthConfig(ts.environment.ActiveDirectoryEndpoint, ts.tenantID)
+		if err != nil {
+			return nil, fmt.Errorf("building the OAuth configuration for device code authentication: %v", err)
+		}
+	}
+	client := &autorest.Client{}
+	deviceCode, err := adal.InitiateDeviceAuth(client, *oauthConfig, ts.clientID, ts.apiserverID)
+	if err != nil {
+		return nil, fmt.Errorf("initialing the device code authentication: %v", err)
+	}
+
+	_, err = fmt.Fprintln(os.Stderr, *deviceCode.Message)
+	if err != nil {
+		return nil, fmt.Errorf("prompting the device code message: %v", err)
+	}
+
+	token, err := adal.WaitForUserCompletion(client, deviceCode)
+	if err != nil {
+		return nil, fmt.Errorf("waiting for device code authentication to complete: %v", err)
+	}
+
+	return &azureToken{
+		token:       *token,
+		environment: ts.environment.Name,
+		clientID:    ts.clientID,
+		tenantID:    ts.tenantID,
+		apiserverID: ts.apiserverID,
+	}, nil
+}