signer/core/apitypes: support more input types for eip-712 encoding (#26074)

* apitypes: synchronize handling of types

* signer/core/apitypes: improve array check

* apitypes: add a test for big.Int -> int32

* signer/core/apitypes: Add a test for parsing addresses from [20]byte, []byte and string

* signer/core/apitypes: add some testcases

Co-authored-by: Felix Lange <fjl@twurst.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>

signer/core/apitypes/signed_data_internal_test.go

@@ -21,6 +21,7 @@ import (
 	"math/big"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
@@ -84,6 +85,55 @@ func TestBytesPadding(t *testing.T) {
 	}
 }
 
+func TestParseAddress(t *testing.T) {
+	tests := []struct {
+		Input  interface{}
+		Output []byte // nil => error
+	}{
+		{
+			Input:  [20]byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14},
+			Output: common.FromHex("0x0000000000000000000000000102030405060708090A0B0C0D0E0F1011121314"),
+		},
+		{
+			Input:  "0x0102030405060708090A0B0C0D0E0F1011121314",
+			Output: common.FromHex("0x0000000000000000000000000102030405060708090A0B0C0D0E0F1011121314"),
+		},
+		{
+			Input:  []byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14},
+			Output: common.FromHex("0x0000000000000000000000000102030405060708090A0B0C0D0E0F1011121314"),
+		},
+		// Various error-cases:
+		{Input: "0x000102030405060708090A0B0C0D0E0F1011121314"}, // too long string
+		{Input: "0x01"}, // too short string
+		{Input: ""},
+		{Input: [32]byte{}},       // too long fixed-size array
+		{Input: [21]byte{}},       // too long fixed-size array
+		{Input: make([]byte, 19)}, // too short slice
+		{Input: make([]byte, 21)}, // too long slice
+		{Input: nil},
+	}
+
+	d := TypedData{}
+	for i, test := range tests {
+		val, err := d.EncodePrimitiveValue("address", test.Input, 1)
+		if test.Output == nil {
+			if err == nil {
+				t.Errorf("test %d: expected error, got no error (result %x)", i, val)
+			}
+			continue
+		}
+		if err != nil {
+			t.Errorf("test %d: expected no error, got %v", i, err)
+		}
+		if have, want := len(val), 32; have != want {
+			t.Errorf("test %d: have len %d, want %d", i, have, want)
+		}
+		if !bytes.Equal(val, test.Output) {
+			t.Errorf("test %d: want %x, have %x", i, test.Output, val)
+		}
+	}
+}
+
 func TestParseBytes(t *testing.T) {
 	for i, tt := range []struct {
 		v   interface{}
@@ -98,6 +148,9 @@ func TestParseBytes(t *testing.T) {
 		{"not a hex string", nil},
 		{15, nil},
 		{nil, nil},
+		{[2]byte{12, 34}, []byte{12, 34}},
+		{[8]byte{12, 34, 56, 78, 90, 12, 34, 56}, []byte{12, 34, 56, 78, 90, 12, 34, 56}},
+		{[16]byte{12, 34, 56, 78, 90, 12, 34, 56, 12, 34, 56, 78, 90, 12, 34, 56}, []byte{12, 34, 56, 78, 90, 12, 34, 56, 12, 34, 56, 78, 90, 12, 34, 56}},
 	} {
 		out, ok := parseBytes(tt.v)
 		if tt.exp == nil {
@@ -123,6 +176,7 @@ func TestParseInteger(t *testing.T) {
 	}{
 		{"uint32", "-123", nil},
 		{"int32", "-123", big.NewInt(-123)},
+		{"int32", big.NewInt(-124), big.NewInt(-124)},
 		{"uint32", "0xff", big.NewInt(0xff)},
 		{"int8", "0xffff", nil},
 	} {

signer/core/apitypes/types.go

@@ -418,6 +418,14 @@ func (typedData *TypedData) EncodeData(primaryType string, data map[string]inter
 
 // Attempt to parse bytes in different formats: byte array, hex string, hexutil.Bytes.
 func parseBytes(encType interface{}) ([]byte, bool) {
+	// Handle array types.
+	val := reflect.ValueOf(encType)
+	if val.Kind() == reflect.Array && val.Type().Elem().Kind() == reflect.Uint8 {
+		v := reflect.MakeSlice(reflect.TypeOf([]byte{}), val.Len(), val.Len())
+		reflect.Copy(v, val)
+		return v.Bytes(), true
+	}
+
 	switch v := encType.(type) {
 	case []byte:
 		return v, true
@@ -458,6 +466,8 @@ func parseInteger(encType string, encValue interface{}) (*big.Int, error) {
 	switch v := encValue.(type) {
 	case *math.HexOrDecimal256:
 		b = (*big.Int)(v)
+	case *big.Int:
+		b = v
 	case string:
 		var hexIntValue math.HexOrDecimal256
 		if err := hexIntValue.UnmarshalText([]byte(v)); err != nil {
@@ -490,13 +500,23 @@ func parseInteger(encType string, encValue interface{}) (*big.Int, error) {
 func (typedData *TypedData) EncodePrimitiveValue(encType string, encValue interface{}, depth int) ([]byte, error) {
 	switch encType {
 	case "address":
-		stringValue, ok := encValue.(string)
-		if !ok || !common.IsHexAddress(stringValue) {
-			return nil, dataMismatchError(encType, encValue)
-		}
 		retval := make([]byte, 32)
-		copy(retval[12:], common.HexToAddress(stringValue).Bytes())
-		return retval, nil
+		switch val := encValue.(type) {
+		case string:
+			if common.IsHexAddress(val) {
+				copy(retval[12:], common.HexToAddress(val).Bytes())
+				return retval, nil
+			}
+		case []byte:
+			if len(val) == 20 {
+				copy(retval[12:], val)
+				return retval, nil
+			}
+		case [20]byte:
+			copy(retval[12:], val[:])
+			return retval, nil
+		}
+		return nil, dataMismatchError(encType, encValue)
 	case "bool":
 		boolValue, ok := encValue.(bool)
 		if !ok {