add eip191 signmode support

x/auth/tx/eip191.go

@@ -0,0 +1,64 @@
+package tx
+
+import (
+	"fmt"
+	"strconv"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	signingtypes "github.com/cosmos/cosmos-sdk/types/tx/signing"
+	"github.com/cosmos/cosmos-sdk/x/auth/migrations/legacytx"
+	"github.com/cosmos/cosmos-sdk/x/auth/signing"
+)
+
+const EIP191MessagePrefix = "\x19Ethereum Signed Message:\n"
+
+const eip191NonCriticalFieldsError = "protobuf transaction contains unknown non-critical fields. This is a transaction malleability issue and SIGN_MODE_EIP_191 cannot be used."
+
+// SignModeEIP191Handler defines the SIGN_MODE_DIRECT SignModeHandler
+type SignModeEIP191Handler struct{}
+
+var _ signing.SignModeHandler = SignModeEIP191Handler{}
+
+// DefaultMode implements SignModeHandler.DefaultMode
+func (SignModeEIP191Handler) DefaultMode() signingtypes.SignMode {
+	return signingtypes.SignMode_SIGN_MODE_EIP_191
+}
+
+// Modes implements SignModeHandler.Modes
+func (SignModeEIP191Handler) Modes() []signingtypes.SignMode {
+	return []signingtypes.SignMode{signingtypes.SignMode_SIGN_MODE_EIP_191}
+}
+
+// GetSignBytes implements SignModeHandler.GetSignBytes
+func (SignModeEIP191Handler) GetSignBytes(mode signingtypes.SignMode, data signing.SignerData, tx sdk.Tx) ([]byte, error) {
+	if mode != signingtypes.SignMode_SIGN_MODE_EIP_191 {
+		return nil, fmt.Errorf("expected %s, got %s", signingtypes.SignMode_SIGN_MODE_EIP_191, mode)
+	}
+
+	protoTx, ok := tx.(*wrapper)
+	if !ok {
+		return nil, fmt.Errorf("can only handle a protobuf Tx, got %T", tx)
+	}
+
+	if protoTx.txBodyHasUnknownNonCriticals {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, eip191NonCriticalFieldsError)
+	}
+
+	body := protoTx.tx.Body
+
+	if len(body.ExtensionOptions) != 0 || len(body.NonCriticalExtensionOptions) != 0 {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "SignMode_SIGN_MODE_EIP_191 does not support protobuf extension options.")
+	}
+
+	aminoJSONBz := legacytx.StdSignBytes(
+		data.ChainID, data.AccountNumber, data.Sequence, protoTx.GetTimeoutHeight(),
+		legacytx.StdFee{Amount: protoTx.GetFee(), Gas: protoTx.GetGas()},
+		tx.GetMsgs(), protoTx.GetMemo(), protoTx.GetTip(),
+	)
+
+	return append(append(
+		[]byte(EIP191MessagePrefix),
+		[]byte(strconv.Itoa(len(aminoJSONBz)))...,
+	), aminoJSONBz...), nil
+}

x/auth/tx/mode_handler.go

@@ -12,6 +12,7 @@ var DefaultSignModes = []signingtypes.SignMode{
 	signingtypes.SignMode_SIGN_MODE_DIRECT,
 	signingtypes.SignMode_SIGN_MODE_DIRECT_AUX,
 	signingtypes.SignMode_SIGN_MODE_LEGACY_AMINO_JSON,
+	signingtypes.SignMode_SIGN_MODE_EIP_191,
 }
 
 // makeSignModeHandler returns the default protobuf SignModeHandler supporting
@@ -31,6 +32,8 @@ func makeSignModeHandler(modes []signingtypes.SignMode) signing.SignModeHandler
 			handlers[i] = signModeLegacyAminoJSONHandler{}
 		case signingtypes.SignMode_SIGN_MODE_DIRECT_AUX:
 			handlers[i] = signModeDirectAuxHandler{}
+		case signingtypes.SignMode_SIGN_MODE_EIP_191:
+			handlers[i] = SignModeEIP191Handler{}
 		default:
 			panic(fmt.Errorf("unsupported sign mode %+v", mode))
 		}