*: Convert slices to arrays instead of copy where possible (#595)

bearer/bearer.go

@@ -48,7 +48,9 @@ func (b *Token) readFromV2(m acl.BearerToken, checkFieldPresence bool) error {
 
 	eaclTable := body.GetEACL()
 	if b.eaclTableSet = eaclTable != nil; b.eaclTableSet {
-		b.eaclTable = *eacl.NewTableFromV2(eaclTable)
+		if err = b.eaclTable.ReadFromV2(*eaclTable); err != nil {
+			return fmt.Errorf("invalid eACL")
+		}
 	} else if checkFieldPresence {
 		return errors.New("missing eACL table")
 	}

client/container.go

@@ -437,14 +437,15 @@ func (c *Client) ContainerEACL(ctx context.Context, id cid.ID, prm PrmContainerE
 	}
 	cc.result = func(r responseV2) {
 		resp := r.(*v2container.GetExtendedACLResponse)
-
+		const fieldEACL = "eACL"
 		eACL := resp.GetBody().GetEACL()
 		if eACL == nil {
-			cc.err = newErrMissingResponseField("eACL")
+			cc.err = newErrMissingResponseField(fieldEACL)
 			return
 		}
-
-		res = *eacl.NewTableFromV2(eACL)
+		if cc.err = res.ReadFromV2(*eACL); cc.err != nil {
+			cc.err = newErrInvalidResponseField(fieldEACL, cc.err)
+		}
 	}
 
 	// process call

container/id/id.go

@@ -65,14 +65,14 @@ func (id *ID) Decode(src []byte) error {
 		return fmt.Errorf("invalid length %d", len(src))
 	}
 
-	copy(id[:], src)
+	*id = ID(src)
 
 	return nil
 }
 
 // SetSHA256 sets container identifier value to SHA256 checksum of container structure.
 func (id *ID) SetSHA256(v [sha256.Size]byte) {
-	copy(id[:], v[:])
+	*id = v
 }
 
 // Equals defines a comparison relation between two ID instances.

eacl/table.go

@@ -77,9 +77,50 @@ func (t *Table) AddRecord(r *Record) {
 	}
 }
 
+// ReadFromV2 reads Table from the [v2acl.Table] message. Returns an error if
+// the message is malformed according to the NeoFS API V2 protocol. The message
+// must not be nil.
+//
+// ReadFromV2 is intended to be used by the NeoFS API V2 client/server
+// implementation only and is not expected to be directly used by applications.
+//
+// See also [Table.ToV2].
+func (t *Table) ReadFromV2(m v2acl.Table) error {
+	// set container id
+	if id := m.GetContainerID(); id != nil {
+		if t.cid == nil {
+			t.cid = new(cid.ID)
+		}
+		if err := t.cid.ReadFromV2(*id); err != nil {
+			return fmt.Errorf("invalid container ID: %w", err)
+		}
+	}
+
+	// set version
+	if v := m.GetVersion(); v != nil {
+		ver := version.Version{}
+		ver.SetMajor(v.GetMajor())
+		ver.SetMinor(v.GetMinor())
+
+		t.SetVersion(ver)
+	}
+
+	// set eacl records
+	v2records := m.GetRecords()
+	t.records = make([]Record, len(v2records))
+
+	for i := range v2records {
+		t.records[i] = *NewRecordFromV2(&v2records[i])
+	}
+
+	return nil
+}
+
 // ToV2 converts Table to v2 acl.EACLTable message.
 //
 // Nil Table converts to nil.
+//
+// See also [Table.ReadFromV2].
 func (t *Table) ToV2() *v2acl.Table {
 	if t == nil {
 		return nil
@@ -133,6 +174,9 @@ func CreateTable(cid cid.ID) *Table {
 }
 
 // NewTableFromV2 converts v2 acl.EACLTable message to Table.
+//
+// Deprecated: BUG: container ID length is not checked. Use [Table.ReadFromV2]
+// instead.
 func NewTableFromV2(table *v2acl.Table) *Table {
 	t := new(Table)
 
@@ -187,20 +231,11 @@ func (t Table) SignedData() []byte {
 
 // Unmarshal unmarshals protobuf binary representation of Table.
 func (t *Table) Unmarshal(data []byte) error {
-	fV2 := new(v2acl.Table)
-	if err := fV2.Unmarshal(data); err != nil {
-		return err
-	}
-
-	// format checks
-	err := checkFormat(fV2)
-	if err != nil {
+	var m v2acl.Table
+	if err := m.Unmarshal(data); err != nil {
 		return err
 	}
-
-	*t = *NewTableFromV2(fV2)
-
-	return nil
+	return t.ReadFromV2(m)
 }
 
 // MarshalJSON encodes Table to protobuf JSON format.
@@ -210,19 +245,11 @@ func (t *Table) MarshalJSON() ([]byte, error) {
 
 // UnmarshalJSON decodes Table from protobuf JSON format.
 func (t *Table) UnmarshalJSON(data []byte) error {
-	tV2 := new(v2acl.Table)
-	if err := tV2.UnmarshalJSON(data); err != nil {
-		return err
-	}
-
-	err := checkFormat(tV2)
-	if err != nil {
+	var m v2acl.Table
+	if err := m.UnmarshalJSON(data); err != nil {
 		return err
 	}
-
-	*t = *NewTableFromV2(tV2)
-
-	return nil
+	return t.ReadFromV2(m)
 }
 
 // EqualTables compares Table with each other.
@@ -249,19 +276,3 @@ func EqualTables(t1, t2 Table) bool {
 
 	return true
 }
-
-func checkFormat(v2 *v2acl.Table) error {
-	var cID cid.ID
-
-	cidV2 := v2.GetContainerID()
-	if cidV2 == nil {
-		return nil
-	}
-
-	err := cID.ReadFromV2(*cidV2)
-	if err != nil {
-		return fmt.Errorf("could not convert V2 container ID: %w", err)
-	}
-
-	return nil
-}

eacl/table_test.go

@@ -31,6 +31,9 @@ func TestTable(t *testing.T) {
 
 	newTable := eacl.NewTableFromV2(v2)
 	require.Equal(t, table, newTable)
+	var res eacl.Table
+	require.NoError(t, res.ReadFromV2(*v2))
+	require.Equal(t, table, newTable)
 
 	t.Run("new from nil v2 table", func(t *testing.T) {
 		require.Equal(t, new(eacl.Table), eacl.NewTableFromV2(nil))

object/id/id.go

@@ -65,14 +65,14 @@ func (id *ID) Decode(src []byte) error {
 		return fmt.Errorf("invalid length %d", len(src))
 	}
 
-	copy(id[:], src)
+	*id = ID(src)
 
 	return nil
 }
 
 // SetSHA256 sets object identifier value to SHA256 checksum.
 func (id *ID) SetSHA256(v [sha256.Size]byte) {
-	copy(id[:], v[:])
+	*id = v
 }
 
 // Equals defines a comparison relation between two ID instances.
@@ -141,9 +141,7 @@ func (id *ID) Unmarshal(data []byte) error {
 		return err
 	}
 
-	copy(id[:], v2.GetValue())
-
-	return nil
+	return id.ReadFromV2(v2)
 }
 
 // MarshalJSON encodes ID to protobuf JSON format.
@@ -161,7 +159,5 @@ func (id *ID) UnmarshalJSON(data []byte) error {
 		return err
 	}
 
-	copy(id[:], v2.GetValue())
-
-	return nil
+	return id.ReadFromV2(v2)
 }

object/id/id_test.go

@@ -180,3 +180,52 @@ func TestID_Encode(t *testing.T) {
 		require.Equal(t, emptyID, id.EncodeToString())
 	})
 }
+
+func TestID_Unmarshal(t *testing.T) {
+	t.Run("invalid value length", func(t *testing.T) {
+		var id ID
+		var m refs.ObjectID
+		for _, tc := range []struct {
+			err string
+			val []byte
+		}{
+			{"invalid length 0", nil},
+			{"invalid length 0", []byte{}},
+			{"invalid length 31", make([]byte, 31)},
+			{"invalid length 33", make([]byte, 33)},
+		} {
+			m.SetValue(tc.val)
+			b := m.StableMarshal(nil)
+			require.EqualError(t, id.Unmarshal(b), tc.err)
+		}
+	})
+}
+
+func TestIDDecodingFailures(t *testing.T) {
+	var id ID
+	var m refs.ObjectID
+	for _, tc := range []struct {
+		err     string
+		corrupt func(*refs.ObjectID)
+	}{
+		{"invalid length 0", func(m *refs.ObjectID) { m.SetValue(nil) }},
+		{"invalid length 0", func(m *refs.ObjectID) { m.SetValue([]byte{}) }},
+		{"invalid length 31", func(m *refs.ObjectID) { m.SetValue(make([]byte, 31)) }},
+		{"invalid length 33", func(m *refs.ObjectID) { m.SetValue(make([]byte, 33)) }},
+	} {
+		id.WriteToV2(&m)
+		tc.corrupt(&m)
+		t.Run(tc.err+"/api", func(t *testing.T) {
+			require.EqualError(t, id.ReadFromV2(m), tc.err)
+		})
+		t.Run(tc.err+"/binary", func(t *testing.T) {
+			b := m.StableMarshal(nil)
+			require.EqualError(t, id.Unmarshal(b), tc.err)
+		})
+		t.Run(tc.err+"/json", func(t *testing.T) {
+			b, err := m.MarshalJSON()
+			require.NoError(t, err, tc.err)
+			require.EqualError(t, id.UnmarshalJSON(b), tc.err)
+		})
+	}
+}

object/search_test.go

@@ -341,11 +341,8 @@ func TestSearchFilters_AddPayloadHashFilter(t *testing.T) {
 func ExampleSearchFilters_AddPayloadHashFilter() {
 	hash, _ := hex.DecodeString("66842cfea090b1d906b52400fae49d86df078c0670f2bdd059ba289ebe24a498")
 
-	var v [sha256.Size]byte
-	copy(v[:], hash[:sha256.Size])
-
 	var cs checksum.Checksum
-	cs.SetSHA256(v)
+	cs.SetSHA256([sha256.Size]byte(hash))
 
 	fmt.Println(hex.EncodeToString(cs.Value()))
 	// Output: 66842cfea090b1d906b52400fae49d86df078c0670f2bdd059ba289ebe24a498
@@ -377,11 +374,8 @@ func TestSearchFilters_AddHomomorphicHashFilter(t *testing.T) {
 func ExampleSearchFilters_AddHomomorphicHashFilter() {
 	hash, _ := hex.DecodeString("7e302ebb3937e810feb501965580c746048db99cebd095c3ce27022407408bf904dde8d9aa8085d2cf7202345341cc947fa9d722c6b6699760d307f653815d0c")
 
-	var v [tz.Size]byte
-	copy(v[:], hash[:tz.Size])
-
 	var cs checksum.Checksum
-	cs.SetTillichZemor(v)
+	cs.SetTillichZemor([tz.Size]byte(hash))
 
 	fmt.Println(hex.EncodeToString(cs.Value()))
 	// Output: 7e302ebb3937e810feb501965580c746048db99cebd095c3ce27022407408bf904dde8d9aa8085d2cf7202345341cc947fa9d722c6b6699760d307f653815d0c

object/slicer/slicer.go

@@ -600,17 +600,11 @@ func (x *PayloadWriter) _writeChild(ctx context.Context, meta dynamicObjectMetad
 func flushObjectMetadata(signer neofscrypto.Signer, meta dynamicObjectMetadata, header *object.Object) (oid.ID, error) {
 	var cs checksum.Checksum
 
-	var csBytes [sha256.Size]byte
-	copy(csBytes[:], meta.checksum.Sum(nil))
-
-	cs.SetSHA256(csBytes)
+	cs.SetSHA256([sha256.Size]byte(meta.checksum.Sum(nil)))
 	header.SetPayloadChecksum(cs)
 
 	if meta.homomorphicChecksum != nil {
-		var csHomoBytes [tz.Size]byte
-		copy(csHomoBytes[:], meta.homomorphicChecksum.Sum(nil))
-
-		cs.SetTillichZemor(csHomoBytes)
+		cs.SetTillichZemor([tz.Size]byte(meta.homomorphicChecksum.Sum(nil)))
 		header.SetPayloadHomomorphicHash(cs)
 	}
 

session/common.go

@@ -32,7 +32,7 @@ type contextReader func(session.TokenContext, bool) error
 
 func (x commonData) copyTo(dst *commonData) {
 	dst.idSet = x.idSet
-	copy(dst.id[:], x.id[:])
+	dst.id = x.id
 
 	dst.issuerSet = x.issuerSet
 	iss := x.issuer