Merge pull request #2893 from ethereum/fix-getstorageat-rpc

fix storageAt rpc call

libs/remix-simulator/src/VmProxy.ts

@@ -3,7 +3,7 @@ const { hexListFromBNs, formatMemory } = util
 import { helpers } from '@remix-project/remix-lib'
 const  { normalizeHexAddress } = helpers.ui
 import { ConsoleLogs } from '@remix-project/remix-lib'
-import { toChecksumAddress, BN, bufferToHex, Address } from 'ethereumjs-util'
+import { toChecksumAddress, BN, keccak, bufferToHex, Address, toBuffer } from 'ethereumjs-util'
 import Web3 from 'web3'
 import { ethers } from 'ethers'
 import { VMContext } from './vm-context'
@@ -40,7 +40,6 @@ export class VmProxy {
   utils
   txsMapBlock
   blocks
-  latestBlockNumber
 
   constructor (vmContext: VMContext) {
     this.vmContext = vmContext
@@ -62,6 +61,7 @@ export class VmProxy {
     this.eth.getTransactionReceipt = (txHash, cb) => this.getTransactionReceipt(txHash, cb)
     this.eth.getTransactionFromBlock = (blockNumber, txIndex, cb) => this.getTransactionFromBlock(blockNumber, txIndex, cb)
     this.eth.getBlockNumber = (cb) => this.getBlockNumber(cb)
+    this.eth.getStorageAt = (address: string, position: string, blockNumber: string, cb) => this.getStorageAt(address, position, blockNumber, cb)
     this.debug.traceTransaction = (txHash, options, cb) => this.traceTransaction(txHash, options, cb)
     this.debug.storageRangeAt = (blockNumber, txIndex, address, start, maxLength, cb) => this.storageRangeAt(blockNumber, txIndex, address, start, maxLength, cb)
     this.debug.preimage = (hashedKey, cb) => this.preimage(hashedKey, cb)
@@ -83,7 +83,6 @@ export class VmProxy {
     this.utils = Web3.utils || []
     this.txsMapBlock = {}
     this.blocks = {}
-    this.latestBlockNumber = 0
   }
 
   setVM (vm) {
@@ -132,6 +131,7 @@ export class VmProxy {
     this.txs[this.processingHash] = tx
     this.txsReceipt[this.processingHash] = tx
     this.storageCache[this.processingHash] = {}
+    this.storageCache['after_' + this.processingHash] = {}
     if (data.to) {
       try {
         const storage = await this.vm.stateManager.dumpStorage(data.to)
@@ -175,6 +175,17 @@ export class VmProxy {
     const status = data.execResult.exceptionError ? 0 : 1
     this.txsReceipt[this.processingHash].status = `0x${status}`
 
+    const to = this.txs[this.processingHash].to
+    if (to) {
+      try {
+        const account = Address.fromString(to)
+        const storage = await this.vm.stateManager.dumpStorage(account)
+        this.storageCache['after_' + this.processingHash][to] = storage
+      } catch (e) {
+        console.log(e)
+      }
+    }
+
     if (data.createdAddress) {
       const address = data.createdAddress.toString()
       this.vmTraces[this.processingHash].return = toChecksumAddress(address)
@@ -294,19 +305,31 @@ export class VmProxy {
     }
   }
 
-  storageRangeAt (blockNumber, txIndex, address, start, maxLength, cb) {
+  getStorageAt (address: string, position: string, blockNumber: string, cb) {
     // we don't use the range params here
     address = toChecksumAddress(address)
+    
+    blockNumber = blockNumber === 'latest' ? this.vmContext.latestBlockNumber : blockNumber
 
-    let txHash
-    if (txIndex === 'latest') {
-      txHash = this.lastProcessedStorageTxHash[address]
-    } else {
-      const block = this.vmContext.blocks[blockNumber]
-      txHash = '0x' + block.transactions[txIndex].hash().toString('hex')
+    const block = this.vmContext.blocks[blockNumber]
+    const txHash = '0x' + block.transactions[block.transactions.length - 1].hash().toString('hex')
+
+    if (this.storageCache['after_' + txHash] && this.storageCache['after_' + txHash][address]) {
+      const slot = '0x' + keccak(toBuffer(ethers.utils.hexZeroPad(position, 32))).toString('hex')
+      const storage = this.storageCache['after_' + txHash][address]
+      return cb(null, storage[slot].value)
     }
-    
-    
+    // Before https://github.com/ethereum/remix-project/pull/1703, it used to throw error as
+    // 'unable to retrieve storage ' + txIndex + ' ' + address
+    cb(null, { storage: {} })
+  }
+
+  storageRangeAt (blockNumber, txIndex, address, start, maxLength, cb) {
+    // we don't use the range params here
+    address = toChecksumAddress(address)
+
+    const block = this.vmContext.blocks[blockNumber]
+    const txHash = '0x' + block.transactions[txIndex].hash().toString('hex')
 
     if (this.storageCache[txHash] && this.storageCache[txHash][address]) {
       const storage = this.storageCache[txHash][address]

libs/remix-simulator/src/methods/blocks.ts

@@ -1,7 +1,7 @@
 import Web3 from 'web3'
-
+import { VMContext } from '../vm-context'
 export class Blocks {
-  vmContext
+  vmContext: VMContext
   coinbase: string
   TX_INDEX = '0x0' // currently there's always only 1 tx per block, so the transaction index will always be 0x0
   constructor (vmContext, _options) {
@@ -73,7 +73,7 @@ export class Blocks {
       stateRoot: this.toHex(block.header.stateRoot),
       miner: this.coinbase,
       difficulty: this.toHex(block.header.difficulty),
-      totalDifficulty: this.toHex(block.header.totalDifficulty),
+      totalDifficulty: this.toHex((block.header as any).totalDifficulty),
       extraData: this.toHex(block.header.extraData),
       size: '0x027f07', // 163591
       gasLimit: this.toHex(block.header.gasLimit),
@@ -127,7 +127,7 @@ export class Blocks {
       stateRoot: this.toHex(block.header.stateRoot),
       miner: this.coinbase,
       difficulty: this.toHex(block.header.difficulty),
-      totalDifficulty: this.toHex(block.header.totalDifficulty),
+      totalDifficulty: this.toHex((block.header as any).totalDifficulty),
       extraData: this.toHex(block.header.extraData),
       size: '0x027f07', // 163591
       gasLimit: this.toHex(block.header.gasLimit),
@@ -173,15 +173,10 @@ export class Blocks {
   }
 
   eth_getStorageAt (payload, cb) {
-    const [address, position, blockNumber] = payload.params
-
-    this.vmContext.web3().debug.storageRangeAt(blockNumber, 'latest', address.toLowerCase(), position, 1, (err, result) => {
-      if (err || (result.storage && Object.values(result.storage).length === 0)) {
-        return cb(err, '')
-      }
-
-      const value = Object.values(result.storage)[0]['value']
-      cb(err, value)
-    })
+    return this.vmContext.web3().eth.getStorageAt(
+      payload.params[0],
+      payload.params[1],
+      payload.params[2],
+      cb)
   }
 }

libs/remix-simulator/test/blocks.ts

@@ -212,13 +212,13 @@ describe('blocks', () => {
       let storage = await web3.eth.getStorageAt(contractInstance.options.address, 0)
       assert.deepEqual(storage, '0x64')
 
-      await contractInstance.methods.set(200).send({ from: accounts[0], gas: 400000 })
+      await contractInstance.methods.set(200).send({ from: accounts[0].toLowerCase(), gas: 400000 })
       storage = await web3.eth.getStorageAt(contractInstance.options.address, 0)
-      assert.deepEqual(storage, '0x64')
+      assert.deepEqual(storage, '0xc8')
 
-      await contractInstance.methods.set(200).send({ from: accounts[0], gas: 400000 })
+      await contractInstance.methods.set(1).send({ from: accounts[0].toLowerCase(), gas: 400000 })
       storage = await web3.eth.getStorageAt(contractInstance.options.address, 0)
-      assert.deepEqual(storage, '0xc8')
+      assert.deepEqual(storage, '0x01')
     })
   })
   describe('eth_call', () => {