[#1090] tree: Make workaround for APE checks

* Make `verifyClient` method perform APE check if a container
  was created with zero-filled basic ACL.
* Object verbs are used in APE, until tree verbs are introduced.

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

cmd/frostfs-node/tree.go

@@ -63,7 +63,9 @@ func initTreeService(c *cfg) {
 		tree.WithReplicationChannelCapacity(treeConfig.ReplicationChannelCapacity()),
 		tree.WithReplicationWorkerCount(treeConfig.ReplicationWorkerCount()),
 		tree.WithAuthorizedKeys(treeConfig.AuthorizedKeys()),
-		tree.WithMetrics(c.metricsCollector.TreeService()))
+		tree.WithMetrics(c.metricsCollector.TreeService()),
+		tree.WithAPERouter(c.cfgObject.cfgAccessPolicyEngine.accessPolicyEngine),
+	)
 
 	c.cfgGRPC.performAndSave(func(_ string, _ net.Listener, s *grpc.Server) {
 		tree.RegisterTreeServiceServer(s, c.treeService)

pkg/services/tree/ape.go

@@ -0,0 +1,69 @@
+package tree
+
+import (
+	"encoding/hex"
+	"fmt"
+	"strings"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/ape/converter"
+	aperequest "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/ape/request"
+	core "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/core/container"
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
+	cnrSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/acl"
+	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
+	apechain "git.frostfs.info/TrueCloudLab/policy-engine/pkg/chain"
+	"git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine"
+	nativeschema "git.frostfs.info/TrueCloudLab/policy-engine/schema/native"
+	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
+)
+
+func (s *Service) checkAPE(container *core.Container, cid cid.ID, operation acl.Op, role acl.Role, publicKey *keys.PublicKey) error {
+	namespace := ""
+	cntNamespace, hasNamespace := strings.CutSuffix(cnrSDK.ReadDomain(container.Value).Zone(), ".ns")
+	if hasNamespace {
+		namespace = cntNamespace
+	}
+
+	schemaMethod, err := converter.SchemaMethodFromACLOperation(operation)
+	if err != nil {
+		return apeErr(err)
+	}
+	schemaRole, err := converter.SchemaRoleFromACLRole(role)
+	if err != nil {
+		return apeErr(err)
+	}
+	reqProps := map[string]string{
+		nativeschema.PropertyKeyActorPublicKey: hex.EncodeToString(publicKey.Bytes()),
+		nativeschema.PropertyKeyActorRole:      schemaRole,
+	}
+
+	var resourceName string
+	if namespace == "root" || namespace == "" {
+		resourceName = fmt.Sprintf(nativeschema.ResourceFormatRootContainerObjects, cid.EncodeToString())
+	} else {
+		resourceName = fmt.Sprintf(nativeschema.ResourceFormatNamespaceContainerObjects, namespace, cid.EncodeToString())
+	}
+
+	request := aperequest.NewRequest(
+		schemaMethod,
+		aperequest.NewResource(resourceName, make(map[string]string)),
+		reqProps,
+	)
+
+	status, found, err := s.router.IsAllowed(apechain.Ingress, engine.NewRequestTarget(namespace, cid.EncodeToString()), request)
+	if err != nil {
+		return apeErr(err)
+	}
+	if found && status == apechain.Allow {
+		return nil
+	}
+	err = fmt.Errorf("access to operation %s is denied by access policy engine: %s", schemaMethod, status.String())
+	return apeErr(err)
+}
+
+func apeErr(err error) error {
+	errAccessDenied := &apistatus.ObjectAccessDenied{}
+	errAccessDenied.WriteReason(err.Error())
+	return errAccessDenied
+}

pkg/services/tree/options.go

@@ -9,6 +9,7 @@ import (
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/pilorama"
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/util/logger"
 	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
+	policyengine "git.frostfs.info/TrueCloudLab/policy-engine/pkg/engine"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 )
 
@@ -38,6 +39,8 @@ type cfg struct {
 	containerCacheSize        int
 	authorizedKeys            [][]byte
 
+	router policyengine.ChainRouter
+
 	metrics MetricsRegister
 }
 
@@ -139,3 +142,9 @@ func WithAuthorizedKeys(keys keys.PublicKeys) Option {
 		}
 	}
 }
+
+func WithAPERouter(router policyengine.ChainRouter) Option {
+	return func(c *cfg) {
+		c.router = router
+	}
+}

pkg/services/tree/signature.go

@@ -71,7 +71,7 @@ func (s *Service) verifyClient(req message, cid cidSDK.ID, rawBearer []byte, op
 		return err
 	}
 
-	role, err := roleFromReq(cnr, req, bt)
+	role, pubKey, err := roleAndPubKeyFromReq(cnr, req, bt)
 	if err != nil {
 		return fmt.Errorf("can't get request role: %w", err)
 	}
@@ -79,8 +79,11 @@ func (s *Service) verifyClient(req message, cid cidSDK.ID, rawBearer []byte, op
 	basicACL := cnr.Value.BasicACL()
 	// Basic ACL mask can be unset, if a container operations are performed
 	// with strict APE checks only.
+	//
+	// FIXME(@aarifullin): tree service temporiraly performs APE checks on
+	// object verbs, because tree verbs have not been introduced yet.
 	if basicACL == 0x0 {
-		return nil
+		return s.checkAPE(cnr, cid, op, role, pubKey)
 	}
 
 	if !basicACL.IsOpAllowed(op, role) {
@@ -222,7 +225,7 @@ func SignMessage(m message, key *ecdsa.PrivateKey) error {
 	return nil
 }
 
-func roleFromReq(cnr *core.Container, req message, bt *bearer.Token) (acl.Role, error) {
+func roleAndPubKeyFromReq(cnr *core.Container, req message, bt *bearer.Token) (acl.Role, *keys.PublicKey, error) {
 	role := acl.RoleOthers
 	owner := cnr.Value.Owner()
 
@@ -233,7 +236,7 @@ func roleFromReq(cnr *core.Container, req message, bt *bearer.Token) (acl.Role,
 
 	pub, err := keys.NewPublicKeyFromBytes(rawKey, elliptic.P256())
 	if err != nil {
-		return role, fmt.Errorf("invalid public key: %w", err)
+		return role, nil, fmt.Errorf("invalid public key: %w", err)
 	}
 
 	var reqSigner user.ID
@@ -243,7 +246,7 @@ func roleFromReq(cnr *core.Container, req message, bt *bearer.Token) (acl.Role,
 		role = acl.RoleOwner
 	}
 
-	return role, nil
+	return role, pub, nil
 }
 
 func eACLOp(op acl.Op) eacl.Operation {