Zanzana: Evaluate access with Check request (server-side) (#96213)

* Zanzana: Evaluate access with Check request (server-side)

* Pass parent folder for checking access

* Review suggestions

* remove fixme comment

pkg/services/accesscontrol/acimpl/accesscontrol.go

@@ -8,6 +8,8 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"go.opentelemetry.io/otel"
 
+	"github.com/grafana/authlib/claims"
+
 	"github.com/grafana/grafana/pkg/apimachinery/identity"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/metrics"
@@ -116,9 +118,36 @@ func (a *AccessControl) evaluateZanzana(ctx context.Context, user identity.Reque
 		eval = evaluator
 	}
 
-	return eval.EvaluateCustom(func(action, scope string) (bool, error) {
-		// FIXME: Implement using new schema / apis
-		return false, nil
+	return eval.EvaluateCustom(func(action string, scopes ...string) (bool, error) {
+		// FIXME: handle action with no scopes
+		if len(scopes) == 0 {
+			return false, nil
+		}
+
+		resourceScope := scopes[0]
+		kind, _, identifier := accesscontrol.SplitScope(resourceScope)
+
+		// Parent folder always returned by scope resolver as a second value
+		var parentFolder string
+		if len(scopes) > 1 {
+			_, _, parentFolder = accesscontrol.SplitScope(scopes[1])
+		}
+
+		namespace := claims.OrgNamespaceFormatter(user.GetOrgID())
+		req, ok := zanzana.TranslateToCheckRequest(namespace, action, kind, parentFolder, identifier)
+		if !ok {
+			// unsupported translation
+			return false, errAccessNotImplemented
+		}
+
+		a.log.Debug("evaluating zanzana", "user", user.GetUID(), "namespace", req.Namespace, "verb", req.Verb, "resource", req.Resource, "name", req.Name)
+		res, err := a.zclient.Check(ctx, user, *req)
+
+		if err != nil {
+			return false, err
+		}
+
+		return res.Allowed, nil
 	})
 }
 

pkg/services/accesscontrol/evaluator.go

@@ -11,7 +11,7 @@ import (
 
 var logger = log.New("accesscontrol.evaluator")
 
-type CheckerFn func(action string, scope string) (bool, error)
+type CheckerFn func(action string, scopes ...string) (bool, error)
 
 type Evaluator interface {
 	// Evaluate permissions that are grouped by action
@@ -89,18 +89,12 @@ func (p permissionEvaluator) EvaluateCustom(fn CheckerFn) (bool, error) {
 		return fn(p.Action, "")
 	}
 
-	for _, target := range p.Scopes {
-		matches, err := fn(p.Action, target)
-		if err != nil {
-			return false, err
-		}
-
-		if matches {
-			return true, nil
-		}
+	matches, err := fn(p.Action, p.Scopes...)
+	if err != nil {
+		return false, err
 	}
 
-	return false, nil
+	return matches, nil
 }
 
 func (p permissionEvaluator) MutateScopes(ctx context.Context, mutate ScopeAttributeMutator) (Evaluator, error) {

pkg/services/authz/zanzana/common/info.go

@@ -23,12 +23,19 @@ func GetTypeInfo(group, resource string) (TypeInfo, bool) {
 }
 
 var VerbMapping = map[string]string{
-	utils.VerbGet:              "read",
-	utils.VerbList:             "read",
-	utils.VerbWatch:            "read",
-	utils.VerbCreate:           "create",
-	utils.VerbUpdate:           "write",
-	utils.VerbPatch:            "write",
-	utils.VerbDelete:           "delete",
-	utils.VerbDeleteCollection: "delete",
+	utils.VerbGet:              RelationRead,
+	utils.VerbList:             RelationRead,
+	utils.VerbWatch:            RelationRead,
+	utils.VerbCreate:           RelationCreate,
+	utils.VerbUpdate:           RelationWrite,
+	utils.VerbPatch:            RelationWrite,
+	utils.VerbDelete:           RelationDelete,
+	utils.VerbDeleteCollection: RelationDelete,
+}
+
+var RelationToVerbMapping = map[string]string{
+	RelationRead:   utils.VerbGet,
+	RelationCreate: utils.VerbCreate,
+	RelationWrite:  utils.VerbUpdate,
+	RelationDelete: utils.VerbDelete,
 }

pkg/services/authz/zanzana/zanzana.go

@@ -6,6 +6,8 @@ import (
 
 	openfgav1 "github.com/openfga/api/proto/openfga/v1"
 
+	"github.com/grafana/authlib/authz"
+
 	"github.com/grafana/grafana/pkg/services/authz/zanzana/common"
 )
 
@@ -143,3 +145,32 @@ func MergeFolderResourceTuples(a, b *openfgav1.TupleKey) {
 	vb := b.Condition.Context.Fields["group_resources"]
 	va.GetListValue().Values = append(va.GetListValue().Values, vb.GetListValue().Values...)
 }
+
+func TranslateToCheckRequest(namespace, action, kind, folder, name string) (*authz.CheckRequest, bool) {
+	translation, ok := resourceTranslations[kind]
+
+	if !ok {
+		return nil, false
+	}
+
+	m, ok := translation.mapping[action]
+	if !ok {
+		return nil, false
+	}
+
+	verb, ok := common.RelationToVerbMapping[m.relation]
+	if !ok {
+		return nil, false
+	}
+
+	req := &authz.CheckRequest{
+		Namespace: namespace,
+		Verb:      verb,
+		Group:     translation.group,
+		Resource:  translation.resource,
+		Name:      name,
+		Folder:    folder,
+	}
+
+	return req, true
+}