feat: eip-7702 support in aa-sdk/core, and sma7702 support in account-kit/smart-contracts

.vitest/package.json

@@ -9,7 +9,7 @@
     "prool": "^0.0.15",
     "tar": "^7.4.1",
     "typescript-template": "*",
-    "viem": "2.20.0"
+    "viem": "2.22.6"
   },
   "dependencies": {
     "@aa-sdk/core": "^4.0.0-alpha.8"

aa-sdk/core/package.json

@@ -55,7 +55,7 @@
     "zod": "^3.22.4"
   },
   "peerDependencies": {
-    "viem": "^2.20.0"
+    "viem": "^2.22.6"
   },
   "repository": {
     "type": "git",

aa-sdk/core/src/account/smartContractAccount.ts

@@ -151,9 +151,11 @@ export type ToSmartContractAccountParams<
   getDummySignature: () => Hex | Promise<Hex>;
   encodeExecute: (tx: AccountOp) => Promise<Hex>;
   encodeBatchExecute?: (txs: AccountOp[]) => Promise<Hex>;
+  getNonce?: (nonceKey?: bigint) => Promise<bigint>;
   // if not provided, will default to just using signMessage over the Hex
   signUserOperationHash?: (uoHash: Hex) => Promise<Hex>;
   encodeUpgradeToAndCall?: (params: UpgradeToAndCallParams) => Promise<Hex>;
+  getImplementationAddress?: () => Promise<NullAddress | Address>;
 } & Omit<CustomSource, "signTransaction" | "address">;
 // [!endregion ToSmartContractAccountParams]
 
@@ -260,6 +262,7 @@ export async function toSmartContractAccount<
   source,
   accountAddress,
   getAccountInitCode,
+  getNonce,
   signMessage,
   signTypedData,
   encodeBatchExecute,
@@ -339,11 +342,13 @@ export async function toSmartContractAccount(
     getAccountInitCode,
     signMessage,
     signTypedData,
-    encodeBatchExecute,
     encodeExecute,
+    encodeBatchExecute,
+    getNonce,
     getDummySignature,
     signUserOperationHash,
     encodeUpgradeToAndCall,
+    getImplementationAddress,
   } = params;
 
   const client = createBundlerClient({
@@ -410,16 +415,18 @@ export async function toSmartContractAccount(
     return initCode === "0x";
   };
 
-  const getNonce = async (nonceKey = 0n): Promise<bigint> => {
-    if (!(await isAccountDeployed())) {
-      return 0n;
-    }
-
-    return entryPointContract.read.getNonce([
-      accountAddress_,
-      nonceKey,
-    ]) as Promise<bigint>;
-  };
+  const getNonce_ =
+    getNonce ??
+    (async (nonceKey = 0n): Promise<bigint> => {
+      if (!(await isAccountDeployed())) {
+        return 0n;
+      }
+
+      return entryPointContract.read.getNonce([
+        accountAddress_,
+        nonceKey,
+      ]) as Promise<bigint>;
+    });
 
   const account = toAccount({
     address: accountAddress_,
@@ -468,25 +475,27 @@ export async function toSmartContractAccount(
     return create6492Signature(isDeployed, signature);
   };
 
-  const getImplementationAddress = async (): Promise<NullAddress | Address> => {
-    const storage = await client.getStorageAt({
-      address: account.address,
-      // This is the default slot for the implementation address for Proxies
-      slot: "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc",
+  const getImplementationAddress_ =
+    getImplementationAddress ??
+    (async () => {
+      const storage = await client.getStorageAt({
+        address: account.address,
+        // This is the default slot for the implementation address for Proxies
+        slot: "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc",
+      });
+
+      if (storage == null) {
+        throw new FailedToGetStorageSlotError(
+          "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc",
+          "Proxy Implementation Address"
+        );
+      }
+
+      // The storage slot contains a full bytes32, but we want only the last 20 bytes.
+      // So, slice off the leading `0x` and the first 12 bytes (24 characters), leaving the last 20 bytes, then prefix with `0x`.
+      return `0x${storage.slice(26)}`;
     });
 
-    if (storage == null) {
-      throw new FailedToGetStorageSlotError(
-        "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc",
-        "Proxy Implementation Address"
-      );
-    }
-
-    // The storage slot contains a full bytes32, but we want only the last 20 bytes.
-    // So, slice off the leading `0x` and the first 12 bytes (24 characters), leaving the last 20 bytes, then prefix with `0x`.
-    return `0x${storage.slice(26)}`;
-  };
-
   if (entryPoint.version !== "0.6.0" && entryPoint.version !== "0.7.0") {
     throw new InvalidEntryPointError(chain, entryPoint.version);
   }
@@ -510,9 +519,9 @@ export async function toSmartContractAccount(
     encodeUpgradeToAndCall: encodeUpgradeToAndCall_,
     getEntryPoint: () => entryPoint,
     isAccountDeployed,
-    getAccountNonce: getNonce,
+    getAccountNonce: getNonce_,
     signMessageWith6492,
     signTypedDataWith6492,
-    getImplementationAddress,
+    getImplementationAddress: getImplementationAddress_,
   };
 }

aa-sdk/core/src/client/decorators/bundlerClient.ts

@@ -63,7 +63,10 @@ export type BundlerActions = {
   estimateUserOperationGas<
     TEntryPointVersion extends EntryPointVersion = EntryPointVersion
   >(
-    request: UserOperationRequest<TEntryPointVersion>,
+    request: Extract<
+      UserOperationRequest<TEntryPointVersion>,
+      { authorizationContract?: Address }
+    >,
     entryPoint: Address,
     stateOverride?: StateOverride
   ): Promise<UserOperationEstimateGasResponse<TEntryPointVersion>>;

aa-sdk/core/src/index.ts

@@ -92,6 +92,8 @@ export {
 } from "./errors/useroperation.js";
 export { LogLevel, Logger } from "./logger.js";
 export { middlewareActions } from "./middleware/actions.js";
+export { default7702UserOpSigner } from "./middleware/defaults/7702signer.js";
+export { default7702GasEstimator } from "./middleware/defaults/7702gasEstimator.js";
 export { defaultFeeEstimator } from "./middleware/defaults/feeEstimator.js";
 export { defaultGasEstimator } from "./middleware/defaults/gasEstimator.js";
 export { defaultPaymasterAndData } from "./middleware/defaults/paymasterAndData.js";

aa-sdk/core/src/middleware/defaults/7702gasEstimator.ts

@@ -0,0 +1,44 @@
+import { AccountNotFoundError } from "../../errors/account.js";
+import type { UserOperationStruct } from "../../types.js";
+import type { ClientMiddlewareFn } from "../types";
+import { defaultGasEstimator } from "./gasEstimator.js";
+
+/**
+ * A middleware function to estimate the gas usage of a user operation with an optional custom gas estimator.
+ * This function is only compatible with accounts using EntryPoint v0.7.0.
+ *
+ * @param {ClientMiddlewareFn} [gasEstimator] An optional custom gas estimator function
+ * @returns {Function} A function that takes user operation structure and parameters, estimates gas usage, and returns the estimated user operation
+ */
+export const default7702GasEstimator: (
+  gasEstimator?: ClientMiddlewareFn
+) => ClientMiddlewareFn =
+  (gasEstimator?: ClientMiddlewareFn) => async (struct, params) => {
+    const gasEstimator_ = gasEstimator ?? defaultGasEstimator(params.client);
+
+    const account = params.account ?? params.client.account;
+    if (!account) {
+      throw new AccountNotFoundError();
+    }
+
+    const entryPoint = account.getEntryPoint();
+    if (entryPoint.version !== "0.7.0") {
+      throw new Error(
+        "This middleware is only compatible with EntryPoint v0.7.0"
+      );
+    }
+
+    // todo: this is currently overloading the meaning of the getImplementationAddress method, replace with a dedicated method or clarify intention in docs
+    const implementationAddress = await account.getImplementationAddress();
+
+    // todo: do we need to omit this from estimation if the account is already 7702 delegated? Not omitting for now.
+
+    (struct as UserOperationStruct<"0.7.0">).authorizationContract =
+      implementationAddress;
+
+    const estimatedUO = await gasEstimator_(struct, params);
+
+    estimatedUO.authorizationContract = undefined; // Strip out authorizationContract after estimation.
+
+    return estimatedUO;
+  };

aa-sdk/core/src/middleware/defaults/7702signer.ts

@@ -0,0 +1,82 @@
+import { toHex } from "viem";
+import { isSmartAccountWithSigner } from "../../account/smartContractAccount.js";
+import { AccountNotFoundError } from "../../errors/account.js";
+import { ChainNotFoundError } from "../../errors/client.js";
+import type { ClientMiddlewareFn } from "../types";
+import { defaultUserOpSigner } from "./userOpSigner.js";
+
+/**
+ * Provides a default middleware function for signing user operations with a client account when using ERC-7702 to upgrade local accounts to smart accounts.
+ * If the SmartAccount doesn't support `signAuthorization`, then this just runs the provided `signUserOperation` middleware
+ *
+ * @param {ClientMiddlewareFn} [userOpSigner] Optional user operation signer function
+ * @returns {Function} An async function that processes the user operation and returns the authorized operation with an authorization tuple if necessary
+ */
+export const default7702UserOpSigner: (
+  userOpSigner?: ClientMiddlewareFn
+) => ClientMiddlewareFn =
+  (userOpSigner?: ClientMiddlewareFn) => async (struct, params) => {
+    const userOpSigner_ = userOpSigner ?? defaultUserOpSigner;
+
+    const uo = await userOpSigner_(struct, params);
+
+    const account = params.account ?? params.client.account;
+    const { client } = params;
+
+    if (!account || !isSmartAccountWithSigner(account)) {
+      throw new AccountNotFoundError();
+    }
+
+    const signer = account.getSigner();
+
+    if (!signer.signAuthorization) {
+      return uo;
+    }
+
+    if (!client.chain) {
+      throw new ChainNotFoundError();
+    }
+
+    const code = (await client.getCode({ address: account.address })) ?? "0x";
+    // TODO: this isn't the cleanest because now the account implementation HAS to know that it needs to return an impl address
+    // even if the account is not deployed
+
+    const implAddress = await account.getImplementationAddress();
+
+    const expectedCode = "0xef0100" + implAddress.slice(2);
+
+    if (code.toLowerCase() === expectedCode.toLowerCase()) {
+      return uo;
+    }
+
+    const accountNonce = await params.client.getTransactionCount({
+      address: account.address,
+    });
+
+    const {
+      r,
+      s,
+      v,
+      yParity = v ? v - 27n : undefined,
+    } = await signer.signAuthorization({
+      chainId: client.chain.id,
+      contractAddress: implAddress,
+      nonce: accountNonce,
+    });
+
+    if (yParity === undefined) {
+      throw new Error("Invalid signature: missing yParity or v");
+    }
+
+    return {
+      ...uo,
+      authorizationTuple: {
+        chainId: client.chain.id,
+        nonce: toHex(accountNonce), // deepHexlify doesn't encode number(0) correctly, it returns "0x"
+        address: implAddress,
+        r,
+        s,
+        yParity: toHex(yParity),
+      },
+    };
+  };

aa-sdk/core/src/signer/local-account.ts

@@ -14,6 +14,7 @@ import {
   privateKeyToAccount,
 } from "viem/accounts";
 import type { SmartAccountSigner } from "./types.js";
+import type { Authorization } from "viem/experimental";
 
 /**
  * Represents a local account signer and provides methods to sign messages and transactions, as well as static methods to create the signer from mnemonic or private key.
@@ -95,6 +96,33 @@ export class LocalAccountSigner<
     return this.inner.signTypedData(params);
   };
 
+  /**
+   * Signs an unsigned authorization using the provided private key account.
+   *
+   * @example
+   * ```ts
+   * import { LocalAccountSigner } from "@aa-sdk/core";
+   * import { generatePrivateKey } from "viem";
+   *
+   * const signer = LocalAccountSigner.mnemonicToAccountSigner(generatePrivateKey());
+   * const signedAuthorization = await signer.signAuthorization({
+   *   contractAddress: "0x1234123412341234123412341234123412341234",
+   *   chainId: 1,
+   *   nonce: 3,
+   * });
+   * ```
+   *
+   * @param {Authorization<number, false>} unsignedAuthorization - The unsigned authorization to be signed.
+   * @returns {Promise<Authorization<number, true>>} A promise that resolves to the signed authorization.
+   */
+
+  signAuthorization(
+    this: LocalAccountSigner<PrivateKeyAccount>,
+    unsignedAuthorization: Authorization<number, false>
+  ): Promise<Authorization<number, true>> {
+    return this.inner.experimental_signAuthorization(unsignedAuthorization);
+  }
+
   /**
    * Returns the address of the inner object in a specific hexadecimal format.
    *

aa-sdk/core/src/signer/types.ts

@@ -5,6 +5,7 @@ import type {
   TypedData,
   TypedDataDefinition,
 } from "viem";
+import type { Authorization } from "viem/experimental";
 
 // [!region SmartAccountAuthenticator]
 /**
@@ -42,5 +43,9 @@ export interface SmartAccountSigner<Inner = any> {
   >(
     params: TypedDataDefinition<TTypedData, TPrimaryType>
   ) => Promise<Hex>;
+
+  signAuthorization?: (
+    unsignedAuthorization: Authorization<number, false>
+  ) => Promise<Authorization<number, true>>;
 }
 // [!endregion SmartAccountSigner]

aa-sdk/core/src/types.ts

@@ -5,6 +5,7 @@ import {
   type StateOverride,
   type TransactionReceipt,
 } from "viem";
+import type { Authorization } from "viem/experimental";
 import type { z } from "zod";
 import type {
   UserOperationFeeOptionsFieldSchema,
@@ -201,15 +202,20 @@ export interface UserOperationRequest_v7 {
 }
 // [!endregion UserOperationRequest_v7]
 
+export type Eip7702ExtendedFields =
+  | { authorizationTuple?: Authorization; authorizationContract?: never }
+  | { authorizationTuple?: never; authorizationContract?: Address };
+
 // [!region UserOperationRequest]
 // Reference: https://eips.ethereum.org/EIPS/eip-4337#definitions
 export type UserOperationRequest<
   TEntryPointVersion extends EntryPointVersion = EntryPointVersion
-> = TEntryPointVersion extends "0.6.0"
+> = (TEntryPointVersion extends "0.6.0"
   ? UserOperationRequest_v6
   : TEntryPointVersion extends "0.7.0"
   ? UserOperationRequest_v7
-  : never;
+  : never) &
+  Eip7702ExtendedFields;
 
 // [!endregion UserOperationRequest]
 
@@ -347,9 +353,10 @@ export interface UserOperationStruct_v7 {
 // [!region UserOperationStruct]
 export type UserOperationStruct<
   TEntryPointVersion extends EntryPointVersion = EntryPointVersion
-> = TEntryPointVersion extends "0.6.0"
+> = (TEntryPointVersion extends "0.6.0"
   ? UserOperationStruct_v6
   : TEntryPointVersion extends "0.7.0"
   ? UserOperationStruct_v7
-  : never;
+  : never) &
+  Eip7702ExtendedFields;
 // [!endregion UserOperationStruct]