func (r *RBACAuthorizer) Authorize(attr authorizer.Attributes) error {
if r.superUser != "" && attr.GetUserName() == r.superUser {
return nil
}
userInfo := &user.DefaultInfo{
Name: attr.GetUserName(),
Groups: attr.GetGroups(),
}
ctx := api.WithNamespace(api.WithUser(api.NewContext(), userInfo), attr.GetNamespace())
// Frame the authorization request as a privilege escalation check.
var requestedRule rbac.PolicyRule
if attr.IsResourceRequest() {
requestedRule = rbac.PolicyRule{
Verbs: []string{attr.GetVerb()},
APIGroups: []string{attr.GetAPIGroup()}, // TODO(ericchiang): add api version here too?
Resources: []string{attr.GetResource()},
ResourceNames: []string{attr.GetName()},
}
} else {
requestedRule = rbac.PolicyRule{
NonResourceURLs: []string{attr.GetPath()},
}
}
return validation.ConfirmNoEscalation(ctx, r.authorizationRuleResolver, []rbac.PolicyRule{requestedRule})
}
// OriginAuthorizerAttributes adapts Kubernetes authorization attributes to Origin authorization attributes
// Note that some info (like resourceName, apiVersion, apiGroup) is not available from the Kubernetes attributes
func OriginAuthorizerAttributes(kattrs kauthorizer.Attributes) (kapi.Context, oauthorizer.AuthorizationAttributes) {
// Build a context to hold the namespace and user info
ctx := kapi.NewContext()
ctx = kapi.WithNamespace(ctx, kattrs.GetNamespace())
ctx = kapi.WithUser(ctx, &user.DefaultInfo{
Name: kattrs.GetUserName(),
Groups: kattrs.GetGroups(),
})
// If the passed attributes already satisfy our interface, use it directly
if oattrs, ok := kattrs.(oauthorizer.AuthorizationAttributes); ok {
return ctx, oattrs
}
// Otherwise build what we can
oattrs := &oauthorizer.DefaultAuthorizationAttributes{
Verb: kattrs.GetVerb(),
Resource: kattrs.GetResource(),
APIGroup: kattrs.GetAPIGroup(),
NonResourceURL: kattrs.IsResourceRequest() == false,
URL: kattrs.GetPath(),
// TODO: add to kube authorizer attributes
// APIVersion string
// ResourceName string
// RequestAttributes interface{}
}
return ctx, oattrs
}
func (r *RBACAuthorizer) Authorize(attr authorizer.Attributes) (bool, string, error) {
if r.superUser != "" && attr.GetUser() != nil && attr.GetUser().GetName() == r.superUser {
return true, "", nil
}
ctx := api.WithNamespace(api.WithUser(api.NewContext(), attr.GetUser()), attr.GetNamespace())
// Frame the authorization request as a privilege escalation check.
var requestedRule rbac.PolicyRule
if attr.IsResourceRequest() {
requestedRule = rbac.PolicyRule{
Verbs: []string{attr.GetVerb()},
APIGroups: []string{attr.GetAPIGroup()}, // TODO(ericchiang): add api version here too?
Resources: []string{attr.GetResource()},
ResourceNames: []string{attr.GetName()},
}
} else {
requestedRule = rbac.PolicyRule{
Verbs: []string{attr.GetVerb()},
NonResourceURLs: []string{attr.GetPath()},
}
}
// TODO(nhlfr): Try to find more lightweight way to check attributes than escalation checks.
err := validation.ConfirmNoEscalation(ctx, r.authorizationRuleResolver, []rbac.PolicyRule{requestedRule})
if err != nil {
return false, err.Error(), nil
}
return true, "", nil
}
// OriginAuthorizerAttributes adapts Kubernetes authorization attributes to Origin authorization attributes
// Note that some info (like resourceName, apiVersion, apiGroup) is not available from the Kubernetes attributes
func OriginAuthorizerAttributes(kattrs kauthorizer.Attributes) (kapi.Context, oauthorizer.AuthorizationAttributes) {
// Build a context to hold the namespace and user info
ctx := kapi.NewContext()
ctx = kapi.WithNamespace(ctx, kattrs.GetNamespace())
ctx = kapi.WithUser(ctx, &user.DefaultInfo{
Name: kattrs.GetUserName(),
Groups: kattrs.GetGroups(),
})
// If we recognize the type, use the embedded type. Do NOT use it directly, because not all things that quack are ducks.
if castAdapterAttributes, ok := kattrs.(AdapterAttributes); ok {
return ctx, castAdapterAttributes.authorizationAttributes
}
// Otherwise build what we can
oattrs := &oauthorizer.DefaultAuthorizationAttributes{
Verb: kattrs.GetVerb(),
APIGroup: kattrs.GetAPIGroup(),
APIVersion: kattrs.GetAPIVersion(),
Resource: kattrs.GetResource(),
ResourceName: kattrs.GetName(),
NonResourceURL: kattrs.IsResourceRequest() == false,
URL: kattrs.GetPath(),
// TODO: add to kube authorizer attributes
// RequestAttributes interface{}
}
if len(kattrs.GetSubresource()) > 0 {
oattrs.Resource = kattrs.GetResource() + "/" + kattrs.GetSubresource()
}
return ctx, oattrs
}
// 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) (err error) {
r := &v1beta1.SubjectAccessReview{
Spec: v1beta1.SubjectAccessReviewSpec{
User: attr.GetUserName(),
Groups: attr.GetGroups(),
},
}
if attr.IsResourceRequest() {
r.Spec.ResourceAttributes = &v1beta1.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 = &v1beta1.NonResourceAttributes{
Path: attr.GetPath(),
Verb: attr.GetVerb(),
}
}
key, err := json.Marshal(r.Spec)
if err != nil {
return err
}
if entry, ok := w.responseCache.Get(string(key)); ok {
r.Status = entry.(v1beta1.SubjectAccessReviewStatus)
} else {
result := w.WithExponentialBackoff(func() restclient.Result {
return w.RestClient.Post().Body(r).Do()
})
if err := result.Error(); 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 err
}
var statusCode int
if result.StatusCode(&statusCode); statusCode < 200 || statusCode >= 300 {
return fmt.Errorf("Error contacting webhook: %d", statusCode)
}
if err := result.Into(r); err != nil {
return err
}
if r.Status.Allowed {
w.responseCache.Add(string(key), r.Status, w.authorizedTTL)
} else {
w.responseCache.Add(string(key), r.Status, w.unauthorizedTTL)
}
}
if r.Status.Allowed {
return nil
}
if r.Status.Reason != "" {
return errors.New(r.Status.Reason)
}
return errors.New("unauthorized")
}
// 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
}
// 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) (err error) {
r := &v1beta1.SubjectAccessReview{
Spec: v1beta1.SubjectAccessReviewSpec{
User: attr.GetUserName(),
Groups: attr.GetGroups(),
},
}
if attr.IsResourceRequest() {
r.Spec.ResourceAttributes = &v1beta1.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 = &v1beta1.NonResourceAttributes{
Path: attr.GetPath(),
Verb: attr.GetVerb(),
}
}
key, err := json.Marshal(r.Spec)
if err != nil {
return err
}
if entry, ok := w.responseCache.Get(string(key)); ok {
r.Status = entry.(v1beta1.SubjectAccessReviewStatus)
} else {
result := w.RestClient.Post().Body(r).Do()
if err := result.Error(); err != nil {
return err
}
if err := result.Into(r); err != nil {
return err
}
go func() {
if r.Status.Allowed {
w.responseCache.Add(string(key), r.Status, w.authorizedTTL)
} else {
w.responseCache.Add(string(key), r.Status, w.unauthorizedTTL)
}
}()
}
if r.Status.Allowed {
return nil
}
if r.Status.Reason != "" {
return errors.New(r.Status.Reason)
}
return errors.New("unauthorized")
}
func resourceMatches(p api.Policy, a authorizer.Attributes) bool {
// A resource policy cannot match a non-resource request
if a.IsResourceRequest() {
if p.Spec.Namespace == "*" || p.Spec.Namespace == a.GetNamespace() {
if p.Spec.Resource == "*" || p.Spec.Resource == a.GetResource() {
if p.Spec.APIGroup == "*" || p.Spec.APIGroup == a.GetAPIGroup() {
return true
}
}
}
}
return false
}
func RuleAllows(requestAttributes authorizer.Attributes, rule rbac.PolicyRule) bool {
if requestAttributes.IsResourceRequest() {
resource := requestAttributes.GetResource()
if len(requestAttributes.GetSubresource()) > 0 {
resource = requestAttributes.GetResource() + "/" + requestAttributes.GetSubresource()
}
return rbac.VerbMatches(rule, requestAttributes.GetVerb()) &&
rbac.APIGroupMatches(rule, requestAttributes.GetAPIGroup()) &&
rbac.ResourceMatches(rule, resource) &&
rbac.ResourceNameMatches(rule, requestAttributes.GetName())
}
return rbac.VerbMatches(rule, requestAttributes.GetVerb()) &&
rbac.NonResourceURLMatches(rule, requestAttributes.GetPath())
}
func nonResourceMatches(p api.Policy, a authorizer.Attributes) bool {
// A non-resource policy cannot match a resource request
if !a.IsResourceRequest() {
// Allow wildcard match
if p.Spec.NonResourcePath == "*" {
return true
}
// Allow exact match
if p.Spec.NonResourcePath == a.GetPath() {
return true
}
// Allow a trailing * subpath match
if strings.HasSuffix(p.Spec.NonResourcePath, "*") && strings.HasPrefix(a.GetPath(), strings.TrimRight(p.Spec.NonResourcePath, "*")) {
return true
}
}
return false
}
// 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) (err error) {
r := &v1beta1.SubjectAccessReview{
Spec: v1beta1.SubjectAccessReviewSpec{
User: attr.GetUserName(),
Groups: attr.GetGroups(),
},
}
if attr.IsResourceRequest() {
r.Spec.ResourceAttributes = &v1beta1.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 = &v1beta1.NonResourceAttributes{
Path: attr.GetPath(),
Verb: attr.GetVerb(),
}
}
result := w.RestClient.Post().Body(r).Do()
if err := result.Error(); err != nil {
return err
}
if err := result.Into(r); err != nil {
return err
}
if r.Status.Allowed {
return nil
}
if r.Status.Reason != "" {
return errors.New(r.Status.Reason)
}
return errors.New("unauthorized")
}