[#1689] ape: Fix validation for overrides in bearer

* APE-overrides are optional for bearer. So, it should validate only set override;
* Bearer can set overrides for containers, not only the one container - validation
  expects for any target type for set override. Basically, APE-overrides for all
  container must be set for namespace target;
* Add unit-test cases to check bearer token validation.

Change-Id: I6b8e19eb73d24f8cd8799bf99b6c551287da67d9
Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>

pkg/services/common/ape/checker.go

@@ -20,7 +20,6 @@ import (
 )
 
 var (
-	errInvalidTargetType        = errors.New("bearer token defines non-container target override")
 	errBearerExpired            = errors.New("bearer token has expired")
 	errBearerInvalidSignature   = errors.New("bearer token has invalid signature")
 	errBearerInvalidContainerID = errors.New("bearer token was created for another container")
@@ -81,7 +80,10 @@ func (c *checkerCoreImpl) CheckAPE(ctx context.Context, prm CheckPrm) error {
 		if prm.BearerToken.Impersonate() {
 			cr = policyengine.NewDefaultChainRouterWithLocalOverrides(c.MorphChainStorage, c.LocalOverrideStorage)
 		} else {
-			override, _ := prm.BearerToken.APEOverride()
+			override, isSet := prm.BearerToken.APEOverride()
+			if !isSet {
+				return errors.New("expected for override within bearer")
+			}
 			cr, err = router.BearerChainFeedRouter(c.LocalOverrideStorage, c.MorphChainStorage, override)
 			if err != nil {
 				return fmt.Errorf("create chain router error: %w", err)
@@ -131,19 +133,19 @@ func isValidBearer(token *bearer.Token, ownerCnr user.ID, cntID cid.ID, publicKe
 	}
 
 	// Check for ape overrides defined in the bearer token.
-	apeOverride, _ := token.APEOverride()
-	if len(apeOverride.Chains) > 0 && apeOverride.Target.TargetType != ape.TargetTypeContainer {
-		return fmt.Errorf("%w: %s", errInvalidTargetType, apeOverride.Target.TargetType.ToV2().String())
-	}
-
-	// Then check if container is either empty or equal to the container in the request.
-	var targetCnr cid.ID
-	err := targetCnr.DecodeString(apeOverride.Target.Name)
-	if err != nil {
-		return fmt.Errorf("invalid cid format: %s", apeOverride.Target.Name)
-	}
-	if !cntID.Equals(targetCnr) {
-		return errBearerInvalidContainerID
+	if apeOverride, isSet := token.APEOverride(); isSet {
+		switch apeOverride.Target.TargetType {
+		case ape.TargetTypeContainer:
+			var targetCnr cid.ID
+			err := targetCnr.DecodeString(apeOverride.Target.Name)
+			if err != nil {
+				return fmt.Errorf("invalid cid format: %s", apeOverride.Target.Name)
+			}
+			if !cntID.Equals(targetCnr) {
+				return errBearerInvalidContainerID
+			}
+		default:
+		}
 	}
 
 	// Then check if container owner signed this token.

pkg/services/tree/signature_test.go

@@ -235,6 +235,48 @@ func TestMessageSign(t *testing.T) {
 			require.Error(t, s.verifyClient(context.Background(), req, cid1, versionTreeID, req.GetBody().GetBearerToken(), acl.OpObjectPut))
 		})
 
+		t.Run("omit override within bt", func(t *testing.T) {
+			t.Run("personated", func(t *testing.T) {
+				bt := testBearerTokenNoOverride()
+				require.NoError(t, bt.Sign(privs[0].PrivateKey))
+				req.Body.BearerToken = bt.Marshal()
+
+				require.NoError(t, SignMessage(req, &privs[1].PrivateKey))
+				require.ErrorContains(t, s.verifyClient(context.Background(), req, cid1, versionTreeID, req.GetBody().GetBearerToken(), acl.OpObjectPut), "expected for override")
+			})
+
+			t.Run("impersonated", func(t *testing.T) {
+				bt := testBearerTokenNoOverride()
+				bt.SetImpersonate(true)
+				require.NoError(t, bt.Sign(privs[0].PrivateKey))
+				req.Body.BearerToken = bt.Marshal()
+
+				require.NoError(t, SignMessage(req, &privs[0].PrivateKey))
+				require.NoError(t, s.verifyClient(context.Background(), req, cid1, versionTreeID, req.GetBody().GetBearerToken(), acl.OpObjectPut))
+			})
+		})
+
+		t.Run("invalid override within bearer token", func(t *testing.T) {
+			t.Run("personated", func(t *testing.T) {
+				bt := testBearerTokenCorruptOverride(privs[1].PublicKey(), privs[2].PublicKey())
+				require.NoError(t, bt.Sign(privs[0].PrivateKey))
+				req.Body.BearerToken = bt.Marshal()
+
+				require.NoError(t, SignMessage(req, &privs[1].PrivateKey))
+				require.ErrorContains(t, s.verifyClient(context.Background(), req, cid1, versionTreeID, req.GetBody().GetBearerToken(), acl.OpObjectPut), "invalid cid")
+			})
+
+			t.Run("impersonated", func(t *testing.T) {
+				bt := testBearerTokenCorruptOverride(privs[1].PublicKey(), privs[2].PublicKey())
+				bt.SetImpersonate(true)
+				require.NoError(t, bt.Sign(privs[0].PrivateKey))
+				req.Body.BearerToken = bt.Marshal()
+
+				require.NoError(t, SignMessage(req, &privs[0].PrivateKey))
+				require.ErrorContains(t, s.verifyClient(context.Background(), req, cid1, versionTreeID, req.GetBody().GetBearerToken(), acl.OpObjectPut), "invalid cid")
+			})
+		})
+
 		t.Run("impersonate", func(t *testing.T) {
 			cnr.Value.SetBasicACL(acl.PublicRWExtended)
 			var bt bearer.Token
@@ -311,6 +353,25 @@ func testBearerToken(cid cid.ID, forPutGet, forGet *keys.PublicKey) bearer.Token
 	return b
 }
 
+func testBearerTokenCorruptOverride(forPutGet, forGet *keys.PublicKey) bearer.Token {
+	var b bearer.Token
+	b.SetExp(currentEpoch + 1)
+	b.SetAPEOverride(bearer.APEOverride{
+		Target: ape.ChainTarget{
+			TargetType: ape.TargetTypeContainer,
+		},
+		Chains: []ape.Chain{{Raw: testChain(forPutGet, forGet).Bytes()}},
+	})
+
+	return b
+}
+
+func testBearerTokenNoOverride() bearer.Token {
+	var b bearer.Token
+	b.SetExp(currentEpoch + 1)
+	return b
+}
+
 func testChain(forPutGet, forGet *keys.PublicKey) *chain.Chain {
 	ruleGet := chain.Rule{
 		Status:    chain.Allow,