use actual kernel version for deployed contracts

Author: johanneskares

.changeset/olive-boats-rest.md

@@ -0,0 +1,5 @@
+---
+"permissionless": patch
+---
+
+Now supports using deployed Kernel accounts with a different version

packages/permissionless/accounts/kernel/toEcdsaKernelSmartAccount.ts

@@ -27,7 +27,7 @@ import {
     getUserOperationHash,
     toSmartAccount
 } from "viem/account-abstraction"
-import { signMessage as _signMessage, getChainId } from "viem/actions"
+import { getChainId } from "viem/actions"
 import { getAction } from "viem/utils"
 import { getAccountNonce } from "../../actions/public/getAccountNonce.js"
 import { getSenderAddress } from "../../actions/public/getSenderAddress.js"
@@ -44,6 +44,7 @@ import {
     VALIDATOR_TYPE
 } from "./constants.js"
 import { encodeCallData } from "./utils/encodeCallData.js"
+import { getActualKernelVersion } from "./utils/getActualKernelVersion.js"
 import { getNonceKeyWithEncoding } from "./utils/getNonceKey.js"
 import { isKernelV2 } from "./utils/isKernelV2.js"
 import { signMessage } from "./utils/signMessage.js"
@@ -479,15 +480,22 @@ export async function toEcdsaKernelSmartAccount<
             return this.signMessage({ message: hash })
         },
         async signMessage({ message }) {
+            const accountAddress = await this.getAddress()
+            const actualKernelVersion = await getActualKernelVersion(
+                client,
+                accountAddress,
+                kernelVersion
+            )
+
             const signature = await signMessage({
                 owner: localOwner,
                 message,
                 accountAddress: await this.getAddress(),
-                kernelVersion,
+                kernelVersion: actualKernelVersion,
                 chainId: await getMemoizedChainId()
             })
 
-            if (isKernelV2(kernelVersion)) {
+            if (isKernelV2(actualKernelVersion)) {
                 return signature
             }
 
@@ -497,15 +505,22 @@ export async function toEcdsaKernelSmartAccount<
             ])
         },
         async signTypedData(typedData) {
+            const accountAddress = await this.getAddress()
+            const actualKernelVersion = await getActualKernelVersion(
+                client,
+                accountAddress,
+                kernelVersion
+            )
+
             const signature = await signTypedData({
                 owner: localOwner,
                 chainId: await getMemoizedChainId(),
                 ...(typedData as TypedDataDefinition),
                 accountAddress: await this.getAddress(),
-                kernelVersion
+                kernelVersion: actualKernelVersion
             })
 
-            if (isKernelV2(kernelVersion)) {
+            if (isKernelV2(actualKernelVersion)) {
                 return signature
             }
 

packages/permissionless/accounts/kernel/utils/getActualKernelVersion.ts

@@ -0,0 +1,67 @@
+import { type Address, type Client, getContract } from "viem"
+import type { KernelVersion } from "../toEcdsaKernelSmartAccount"
+
+// If the kernel contract is already deployed, we can get the actual version from the contract
+export async function getActualKernelVersion(
+    client: Client,
+    address: Address,
+    version: KernelVersion<"0.6" | "0.7">
+): Promise<KernelVersion<"0.6" | "0.7">> {
+    try {
+        const contract = getContract({
+            address,
+            abi: [
+                {
+                    type: "function",
+                    name: "eip712Domain",
+                    inputs: [],
+                    outputs: [
+                        {
+                            name: "fields",
+                            type: "bytes1",
+                            internalType: "bytes1"
+                        },
+                        {
+                            name: "name",
+                            type: "string",
+                            internalType: "string"
+                        },
+                        {
+                            name: "version",
+                            type: "string",
+                            internalType: "string"
+                        },
+                        {
+                            name: "chainId",
+                            type: "uint256",
+                            internalType: "uint256"
+                        },
+                        {
+                            name: "verifyingContract",
+                            type: "address",
+                            internalType: "address"
+                        },
+                        {
+                            name: "salt",
+                            type: "bytes32",
+                            internalType: "bytes32"
+                        },
+                        {
+                            name: "extensions",
+                            type: "uint256[]",
+                            internalType: "uint256[]"
+                        }
+                    ],
+                    stateMutability: "view"
+                }
+            ],
+            client
+        })
+
+        const [, , version] = await contract.read.eip712Domain()
+
+        return version as KernelVersion<"0.6" | "0.7">
+    } catch {
+        return version
+    }
+}