1 files changed, 22 insertions, 0 deletions
diff --git a/packages/order-utils/src/types.ts b/packages/order-utils/src/types.ts
index f79d52359..db0bfb249 100644
--- a/packages/order-utils/src/types.ts
+++ b/packages/order-utils/src/types.ts
@@ -1,3 +1,25 @@
 export enum OrderError {
     InvalidSignature = 'INVALID_SIGNATURE',
 }
+
+/**
+ * The requisite message prefix (is any) to add to an `eth_sign` request.
+ */
+export enum MessagePrefixType {
+    None = 'NONE',
+    EthSign = 'ETH_SIGN',
+    Trezor = 'TREZOR',
+}
+
+/**
+ * Options related to message prefixing of messages sent to `eth_sign`
+ * Some signers prepend a message prefix (e.g Parity Signer, Ledger, TestRPC), while
+ * others require it already be prepended (e.g Metamask). In addition, different signers
+ * expect slightly different prefixes (See: https://github.com/ethereum/go-ethereum/issues/14794).
+ * Depending on the signer that will receive your signing request, you must specify the
+ * desired prefix and whether it should be added before making the `eth_sign` request.
+ */
+export interface MessagePrefixOpts {
+    prefixType: MessagePrefixType;
+    shouldAddPrefixBeforeCallingEthSign: boolean;
+}