From 72914215971cbcd88e7364dab9d8f29fd2e31af0 Mon Sep 17 00:00:00 2001
From: tate <tate@ens.domains>
Date: Tue, 7 May 2024 10:00:29 +1000
Subject: [PATCH 1/2] fix: single case hex address validation

---
 src/coin/eth.test.ts  | 29 +++++++++++++++++++++++------
 src/utils/hex.test.ts | 30 ++++++++++++++++++++++++++++++
 src/utils/hex.ts      | 12 +++++++++++-
 3 files changed, 64 insertions(+), 7 deletions(-)
 create mode 100644 src/utils/hex.test.ts

diff --git a/src/coin/eth.test.ts b/src/coin/eth.test.ts
index 86260c80..b924e346 100644
--- a/src/coin/eth.test.ts
+++ b/src/coin/eth.test.ts
@@ -2,15 +2,32 @@ import { hexToBytes } from "@noble/hashes/utils";
 import { describe, expect, test } from "bun:test";
 import { decodeEthAddress, encodeEthAddress } from "./eth.js";
 
+const prefixlessAddress = "314159265dD8dbb310642f98f50C066173C1259b";
+const hex = "314159265dd8dbb310642f98f50c066173c1259b";
+
+test(`eth address: encode 0x${prefixlessAddress}`, () => {
+  expect(encodeEthAddress(hexToBytes(hex))).toEqual(`0x${prefixlessAddress}`);
+});
+test("eth address: invalid checksum", () => {
+  expect(() =>
+    decodeEthAddress("0x314159265Dd8Dbb310642f98F50C066173C1259b")
+  ).toThrow();
+});
+
 describe.each([
   {
-    text: "0x314159265dD8dbb310642f98f50C066173C1259b",
-    hex: "314159265dd8dbb310642f98f50c066173c1259b",
+    // checksummed address
+    text: `0x${prefixlessAddress}`,
   },
-])("eth address", ({ text, hex }) => {
-  test(`encode: ${text}`, () => {
-    expect(encodeEthAddress(hexToBytes(hex))).toEqual(text);
-  });
+  {
+    // all lowercased address
+    text: `0x${prefixlessAddress.toLowerCase()}`,
+  },
+  {
+    // all uppercased address
+    text: `0x${prefixlessAddress.toUpperCase()}`,
+  },
+])("eth address", ({ text }) => {
   test(`decode: ${text}`, () => {
     expect(decodeEthAddress(text)).toEqual(hexToBytes(hex));
   });
diff --git a/src/utils/hex.test.ts b/src/utils/hex.test.ts
new file mode 100644
index 00000000..a4ea94a6
--- /dev/null
+++ b/src/utils/hex.test.ts
@@ -0,0 +1,30 @@
+import { describe, expect, test } from "bun:test";
+import { isValidChecksumAddress } from "./hex.js";
+
+const prefixlessAddress = "314159265dD8dbb310642f98f50C066173C1259b";
+
+describe("isValidChecksumAddress()", () => {
+  test("valid checksum address", () => {
+    expect(isValidChecksumAddress(`0x${prefixlessAddress}`)).toBeTrue();
+  });
+  test("all lowercased address", () => {
+    expect(
+      isValidChecksumAddress(`0x${prefixlessAddress.toLowerCase()}`)
+    ).toBeTrue();
+  });
+  test("all uppercased address", () => {
+    expect(
+      isValidChecksumAddress(`0x${prefixlessAddress.toUpperCase()}`)
+    ).toBeTrue();
+  });
+  test("invalid checksum address", () => {
+    expect(
+      isValidChecksumAddress("0x314159265Dd8Dbb310642f98F50C066173C1259b")
+    ).toBeFalse();
+  });
+  test("non-hex", () => {
+    expect(
+      isValidChecksumAddress("0x1234567890abcdefghijklmnopqrstuvwxyz0123")
+    ).toBeFalse();
+  });
+});
diff --git a/src/utils/hex.ts b/src/utils/hex.ts
index 8104face..e3f6731b 100644
--- a/src/utils/hex.ts
+++ b/src/utils/hex.ts
@@ -45,7 +45,17 @@ export function isValidChecksumAddress(
   address: string,
   chainId?: number
 ): boolean {
-  return isAddress(address) && checksumAddress(address, chainId) === address;
+  if (!isAddress(address)) return false;
+
+  if (address === checksumAddress(address, chainId)) return true;
+
+  const prefixlessAddress = stripHexPrefix(address);
+  // all lowercase
+  if (prefixlessAddress.toLowerCase() === prefixlessAddress) return true;
+  // all uppercase
+  if (prefixlessAddress.toUpperCase() === prefixlessAddress) return true;
+
+  return false;
 }
 
 export const createHexChecksummedEncoder =

From 14f66fad6008a02a7ac171feb5f4558051530f3f Mon Sep 17 00:00:00 2001
From: tate <tate@ens.domains>
Date: Tue, 7 May 2024 10:00:42 +1000
Subject: [PATCH 2/2] added hex util exports

---
 src/utils/index.ts | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/utils/index.ts b/src/utils/index.ts
index 7122e3dd..52781053 100644
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -44,6 +44,15 @@ export {
   isEvmCoinType,
 } from "./evm.js";
 export { validateFlowAddress } from "./flow.js";
+export {
+  checksumAddress,
+  createHexChecksummedDecoder,
+  createHexChecksummedEncoder,
+  isAddress,
+  isValidChecksumAddress,
+  rawChecksumAddress,
+  stripHexPrefix,
+} from "./hex.js";
 export { decodeLeb128, encodeLeb128 } from "./leb128.js";
 export { validateNearAddress } from "./near.js";
 export { createZcashDecoder, createZcashEncoder } from "./zcash.js";