rpc/nns: support NEP-18 addresses

Signed-off-by: Roman Khimov <[email protected]>

rpc/nns/hashes.go

@@ -2,6 +2,7 @@ package nns
 
 import (
 	"errors"
+	"strings"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/address"
@@ -18,6 +19,9 @@ const ID = 1
 // allows to find contract hashes more easily.
 const ContractTLD = "neofs"
 
+// nep18Prefix is the string prefix containing NEP-18 address attribute name.
+const nep18Prefix = "address="
+
 // ContractStateGetter is the interface required for contract state resolution
 // using a known contract ID.
 type ContractStateGetter interface {
@@ -40,8 +44,10 @@ func InferHash(sg ContractStateGetter) (util.Uint160, error) {
 // contract itself (it doesn't care which data is stored there). It assumes
 // that contracts follow the [ContractTLD] convention, gets simple contract
 // names (like "container" or "netmap") and extracts the hash for the
-// respective NNS record in any of the formats (of which historically there's
-// been a few).
+// respective NNS record in any of the formats:
+//   - hex-encoded reversed hash (the oldest historically)
+//   - plain address string
+//   - attribute-based NEP-18 string
 func (c *ContractReader) ResolveFSContract(name string) (util.Uint160, error) {
 	strs, err := c.Resolve(name+"."+ContractTLD, TXT)
 	if err != nil {
@@ -53,7 +59,7 @@ func (c *ContractReader) ResolveFSContract(name string) (util.Uint160, error) {
 			return h, nil
 		}
 
-		h, err = address.StringToUint160(strs[i])
+		h, err = address.StringToUint160(strings.TrimPrefix(strs[i], nep18Prefix))
 		if err == nil {
 			return h, nil
 		}

rpc/nns/hashes_test.go

@@ -89,6 +89,18 @@ func TestBaseErrors(t *testing.T) {
 	require.Error(t, err)
 
 	h := util.Uint160{1, 2, 3, 4, 5}
+
+	ti.res = &result.Invoke{
+		State: "HALT",
+		Stack: []stackitem.Item{
+			stackitem.Make([]stackitem.Item{
+				stackitem.Make("addr=" + address.Uint160ToString(h)), // Wrong prefix
+			}),
+		},
+	}
+	_, err = r.ResolveFSContract("blah")
+	require.Error(t, err)
+
 	ti.res = &result.Invoke{
 		State: "HALT",
 		Stack: []stackitem.Item{
@@ -112,4 +124,16 @@ func TestBaseErrors(t *testing.T) {
 	res, err = r.ResolveFSContract("blah")
 	require.NoError(t, err)
 	require.Equal(t, h, res)
+
+	ti.res = &result.Invoke{
+		State: "HALT",
+		Stack: []stackitem.Item{
+			stackitem.Make([]stackitem.Item{
+				stackitem.Make("address=" + address.Uint160ToString(h)), // NEP-18
+			}),
+		},
+	}
+	res, err = r.ResolveFSContract("blah")
+	require.NoError(t, err)
+	require.Equal(t, h, res)
 }