// Authorize makes a REST request to the remote service describing the attempted action as a JSON
// serialized api.authorization.v1beta1.SubjectAccessReview object. An example request body is
// provided bellow.
//
//     {
//       "apiVersion": "authorization.k8s.io/v1beta1",
//       "kind": "SubjectAccessReview",
//       "spec": {
//         "resourceAttributes": {
//           "namespace": "kittensandponies",
//           "verb": "GET",
//           "group": "group3",
//           "resource": "pods"
//         },
//         "user": "******",
//         "group": [
//           "group1",
//           "group2"
//         ]
//       }
//     }
//
// The remote service is expected to fill the SubjectAccessReviewStatus field to either allow or
// disallow access. A permissive response would return:
//
//     {
//       "apiVersion": "authorization.k8s.io/v1beta1",
//       "kind": "SubjectAccessReview",
//       "status": {
//         "allowed": true
//       }
//     }
//
// To disallow access, the remote service would return:
//
//     {
//       "apiVersion": "authorization.k8s.io/v1beta1",
//       "kind": "SubjectAccessReview",
//       "status": {
//         "allowed": false,
//         "reason": "user does not have read access to the namespace"
//       }
//     }
//
func (w *WebhookAuthorizer) Authorize(attr authorizer.Attributes) (authorized bool, reason string, err error) {
	r := &authorization.SubjectAccessReview{}
	if user := attr.GetUser(); user != nil {
		r.Spec = authorization.SubjectAccessReviewSpec{
			User:   user.GetName(),
			Groups: user.GetGroups(),
			Extra:  convertToSARExtra(user.GetExtra()),
		}
	}

	if attr.IsResourceRequest() {
		r.Spec.ResourceAttributes = &authorization.ResourceAttributes{
			Namespace:   attr.GetNamespace(),
			Verb:        attr.GetVerb(),
			Group:       attr.GetAPIGroup(),
			Version:     attr.GetAPIVersion(),
			Resource:    attr.GetResource(),
			Subresource: attr.GetSubresource(),
			Name:        attr.GetName(),
		}
	} else {
		r.Spec.NonResourceAttributes = &authorization.NonResourceAttributes{
			Path: attr.GetPath(),
			Verb: attr.GetVerb(),
		}
	}
	key, err := json.Marshal(r.Spec)
	if err != nil {
		return false, "", err
	}
	if entry, ok := w.responseCache.Get(string(key)); ok {
		r.Status = entry.(authorization.SubjectAccessReviewStatus)
	} else {
		var (
			result *authorization.SubjectAccessReview
			err    error
		)
		webhook.WithExponentialBackoff(w.initialBackoff, func() error {
			result, err = w.subjectAccessReview.Create(r)
			return err
		})
		if err != nil {
			// An error here indicates bad configuration or an outage. Log for debugging.
			glog.Errorf("Failed to make webhook authorizer request: %v", err)
			return false, "", err
		}
		r.Status = result.Status
		if r.Status.Allowed {
			w.responseCache.Add(string(key), r.Status, w.authorizedTTL)
		} else {
			w.responseCache.Add(string(key), r.Status, w.unauthorizedTTL)
		}
	}
	return r.Status.Allowed, r.Status.Reason, nil
}
Exemple #2
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// AuthenticateToken implements the authenticator.Token interface.
func (w *WebhookTokenAuthenticator) AuthenticateToken(token string) (user.Info, bool, error) {
	r := &authentication.TokenReview{
		Spec: authentication.TokenReviewSpec{Token: token},
	}
	if entry, ok := w.responseCache.Get(r.Spec); ok {
		r.Status = entry.(authentication.TokenReviewStatus)
	} else {
		var (
			result *authentication.TokenReview
			err    error
		)
		webhook.WithExponentialBackoff(w.initialBackoff, func() error {
			result, err = w.tokenReview.Create(r)
			return err
		})
		if err != nil {
			return nil, false, err
		}
		r.Status = result.Status
		w.responseCache.Add(r.Spec, result.Status, w.ttl)
	}
	if !r.Status.Authenticated {
		return nil, false, nil
	}

	var extra map[string][]string
	if r.Status.User.Extra != nil {
		extra = map[string][]string{}
		for k, v := range r.Status.User.Extra {
			extra[k] = v
		}
	}

	return &user.DefaultInfo{
		Name:   r.Status.User.Username,
		UID:    r.Status.User.UID,
		Groups: r.Status.User.Groups,
		Extra:  extra,
	}, true, nil
}