[Key Manager] CryptoJS.AES (#9)

ts-lib/package.json

@@ -14,10 +14,12 @@
   "dependencies": {
     "@nearfoundation/near-js-encryption-box": "^0.1.2",
     "bs58": "^5.0.0",
+    "crypto-js": "^4.2.0",
     "ethers": "^6.10.0",
     "near-api-js": "^3.0.2"
   },
   "devDependencies": {
+    "@types/crypto-js": "^4.2.2",
     "@types/jest": "^29.5.11",
     "@types/node": "^20.11.10",
     "dotenv": "^16.4.1",

ts-lib/src/encryption/cryptojs.ts

@@ -0,0 +1,46 @@
+/**
+ * This Key Manager is based on the cryptography package provided by
+ * @nearfoundation/near-js-encryption-box
+ * It relies on base58 encoding and requires a nonce to decrypt the key!
+ */
+
+import { HDNodeWallet } from "ethers";
+import { KeyContract } from "../keyContract";
+import { EthKeyManager } from "./interface";
+import { NearAccount } from "../types";
+import CryptoJS from "crypto-js";
+
+export class CryptoJSKeyManager implements EthKeyManager {
+  // EthKeyContract connected to account for `nearPrivateKey`.
+  contract: KeyContract;
+
+  constructor(contract: KeyContract) {
+    this.contract = contract;
+  }
+
+  async encryptAndSetKey(
+    ethWallet: HDNodeWallet,
+    encryptionKey: string,
+  ): Promise<string | undefined> {
+    let encryptedKey = CryptoJS.AES.encrypt(
+      ethWallet.privateKey,
+      encryptionKey,
+    );
+    console.log("Posting Encrypted Key", encryptedKey.toString());
+    await this.contract.methods.set_key({
+      encrypted_key: encryptedKey.toString(),
+    });
+    return undefined;
+  }
+
+  async retrieveAndDecryptKey(
+    nearAccount: NearAccount,
+    // nonce?: string | undefined,
+  ): Promise<string> {
+    const retrievedKey = await this.contract.methods.get_key({
+      account_id: nearAccount.accountId,
+    });
+    let bytes = CryptoJS.AES.decrypt(retrievedKey!, nearAccount.privateKey);
+    return bytes.toString(CryptoJS.enc.Utf8);
+  }
+}

ts-lib/src/index.ts

@@ -1,3 +1,4 @@
 export * from "./encryption/base58";
+export * from "./encryption/cryptojs";
 export * from "./keyContract";
 export * from "./types";