signer/core: EIP-712 encoded data should not reject a Domain without …

…a ChainId (ethereum#21306)

* Do not check for a non-nil ChainId

* Add encoding test

signer/core/signed_data.go

@@ -965,11 +965,7 @@ func isPrimitiveTypeValid(primitiveType string) bool {
 // validate checks if the given domain is valid, i.e. contains at least
 // the minimum viable keys and values
 func (domain *TypedDataDomain) validate() error {
- if domain.ChainId == nil {
- return errors.New("chainId must be specified according to EIP-155")
- }
-
- if len(domain.Name) == 0 && len(domain.Version) == 0 && len(domain.VerifyingContract) == 0 && len(domain.Salt) == 0 {
+ if domain.ChainId == nil && len(domain.Name) == 0 && len(domain.Version) == 0 && len(domain.VerifyingContract) == 0 && len(domain.Salt) == 0 {
  return errors.New("domain is undefined")
  }
 

signer/core/signed_data_test.go

@@ -245,6 +245,10 @@ func TestDomainChainId(t *testing.T) {
  if _, ok := withoutChainID.Domain.Map()["chainId"]; ok {
  t.Errorf("Expected the chainId key to not be present in the domain map")
  }
+ // should encode successfully
+ if _, err := withoutChainID.HashStruct("EIP712Domain", withoutChainID.Domain.Map()); err != nil {
+ t.Errorf("Expected the typedData to encode the domain successfully, got %v", err)
+ }
  withChainID := core.TypedData{
  Types: core.Types{
  "EIP712Domain": []core.Type{
@@ -261,6 +265,10 @@ func TestDomainChainId(t *testing.T) {
  if _, ok := withChainID.Domain.Map()["chainId"]; !ok {
  t.Errorf("Expected the chainId key be present in the domain map")
  }
+ // should encode successfully
+ if _, err := withChainID.HashStruct("EIP712Domain", withChainID.Domain.Map()); err != nil {
+ t.Errorf("Expected the typedData to encode the domain successfully, got %v", err)
+ }
 }
 
 func TestHashStruct(t *testing.T) {