Client/StateManager: storageRangeAt() RPC call / EVMStateManager Interface Extension

packages/client/src/rpc/modules/debug.ts

@@ -1,4 +1,12 @@
-import { Address, TypeOutput, bigIntToHex, bytesToHex, hexToBytes, toType } from '@ethereumjs/util'
+import {
+  Address,
+  TypeOutput,
+  bigIntToHex,
+  bytesToBigInt,
+  bytesToHex,
+  hexToBytes,
+  toType,
+} from '@ethereumjs/util'
 
 import { INTERNAL_ERROR, INVALID_PARAMS } from '../error-code'
 import { getBlockByOption } from '../helpers'
@@ -8,6 +16,7 @@ import type { EthereumClient } from '../..'
 import type { Chain } from '../../blockchain'
 import type { FullEthereumService } from '../../service'
 import type { RpcTx } from '../types'
+import type { Block } from '@ethereumjs/block'
 import type { VM } from '@ethereumjs/vm'
 
 export interface tracerOpts {
@@ -92,6 +101,7 @@ export class Debug {
       [validators.transaction()],
       [validators.blockOption],
     ])
+    this.storageRangeAt = middleware(this.storageRangeAt.bind(this), 5, [[validators.hex]])
   }
 
   /**
@@ -278,4 +288,80 @@ export class Debug {
       message: err.message.toString(),
     }
   }
+
+  /**
+   * Returns a limited set of storage keys belonging to an account.
+   * @param params An array of 5 parameters:
+   *    1. The hash of the block that contains the requested account storage.
+   *    2. The number index of the requested transaction within the block.
+   *    3. The address of the account.
+   *    4. The smallest (hashed) storage key that will be returned. To include the entire range, pass '0x00'.
+   *    5. The maximum number of storage values that will be returned.
+   * @returns A {@link StorageRange} object that will contain at most `limit` entries in its `storage` field.
+   * The object will also contain `nextKey`, the next (hashed) storage key after the range included in `storage`.
+   */
+  async storageRangeAt(params: [string, number, string, string, number]) {
+    const [blockHash, txIndex, account, startKey, limit] = params
+
+    if (txIndex < 0) {
+      throw {
+        code: INTERNAL_ERROR,
+        message: 'txIndex cannot be smaller than 0.',
+      }
+    }
+
+    let address: Address
+    let blockHashBytes: Uint8Array
+    let startKeyBytes: Uint8Array
+    try {
+      address = Address.fromString(account)
+      blockHashBytes = hexToBytes(blockHash)
+      startKeyBytes = hexToBytes(startKey)
+    } catch (err: any) {
+      throw {
+        code: INVALID_PARAMS,
+        message: err.message.toString(),
+      }
+    }
+
+    let block: Block
+    try {
+      block = await this.service.chain.getBlock(blockHashBytes)
+    } catch (err: any) {
+      throw {
+        code: INTERNAL_ERROR,
+        message: 'Could not get requested block hash.',
+      }
+    }
+
+    if (txIndex + 1 > block.transactions.length) {
+      throw {
+        code: INTERNAL_ERROR,
+        message: 'txIndex cannot be larger than the number of transactions in the block.',
+      }
+    }
+
+    try {
+      const block = await this.service.chain.getBlock(hexToBytes(blockHash))
+      const parentBlock = await this.service.chain.getBlock(block.header.parentHash)
+
+      // Copy the VM and run transactions including the relevant transaction.
+      const vmCopy = await this.service.execution.vm.shallowCopy()
+      await vmCopy.stateManager.setStateRoot(parentBlock.header.stateRoot)
+      for (let i = 0; i <= txIndex; i++) {
+        await vmCopy.runTx({ tx: block.transactions[i], block })
+      }
+
+      return await vmCopy.stateManager.dumpStorageRange(
+        address,
+        bytesToBigInt(startKeyBytes),
+        limit
+      )
+    } catch (err: any) {
+      throw {
+        code: INTERNAL_ERROR,
+        message: err.message.toString(),
+      }
+    }
+  }
 }