Issues With Memory String Consumption In Smart Contracts

[baxterjfinch]

When attempting to consume a String in a contract function, ExW3 seems to handle encoding improperly, causing variables to mix and or set improperly in the contracts state.

Smart Contract Example:

pragma solidity >=0.4.22 <0.9.0;

contract Tester {
  address public currentAddr;
  uint256 public currentInt;
  string public sym;

  function setOnlyStringBefore(string memory _sym, address new_addr, uint256 new_int) public {
    currentAddr = new_addr;
    currentInt = new_int;
    sym = _sym;
  }

  function setOnlyStringAfter(address new_addr, uint256 new_int, string memory _sym) public {
    currentAddr = new_addr;
    currentInt = new_int;
    sym = _sym;
  }

  function setOnlyAddrAndInt(address new_addr, uint256 new_int) public {
    currentAddr = new_addr;
    currentInt = new_int;
  }
}

Scenario 1

(Function setOnlyStringBefore) - string is set before address and uint256 in smart contract function parameters

Using ExW3 ->
ExW3.Contract.send(:Tester, :setOnlyStringBefore, ["name", "0x0255bff90b8787f06cf13ab325997cbf3b139c1d", 10], %{from: @contracts_owner, gas: 6000000})

{:ok, "0x1c6ac0864e8e6418cfc743200ee74ad06bb2442bd5842fd73c2d12bb835db0dc"}

In Truffle ->

truffle(k8s)> let test = await Tester.deployed()

truffle(k8s)> test.sym()

Thrown:
{ Error: invalid codepoint at offset 14; unexpected continuation byte (argument="bytes", value={"0":0,"1":0,"2":0,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10":0,"11":0,"12":2,"13":85,"14":191,"15":249,"16":11,"17":135,"18":135,"19":240,"20":108,"21":241,"22":58,"23":179,"24":37,"25":153,"26":124,"27":191,"28":59,"29":19,"30":156,"31":29,"32":0,"33":0,"34":0,"35":0,"36":0,"37":0,"38":0,"39":0,"40":0,"41":0,"42":0,"43":0,"44":0,"45":0,"46":0,"47":0,"48":0,"49":0,"50":0,"51":0,"52":0,"53":0,"54":0,"55":0,"56":0,"57":0,"58":0,"59":0,"60":0,"61":0,"62":0,"63":10,"64":0,"65":0,"66":0,"67":0,"68":0,"69":0,"70":0,"71":0,"72":0,"73":0,"74":0,"75":0,"76":0,"77":0,"78":0,"79":0,"80":0,"81":0,"82":0,"83":0,"84":0,"85":0,"86":0,"87":0,"88":0,"89":0,"90":0,"91":0,"92":0,"93":0,"94":0,"95":4}, code=INVALID_ARGUMENT, version=strings/5.0.5)
    at evalmachine.<anonymous>:0:6
    at sigintHandlersWrap (vm.js:288:15)
    at Script.runInContext (vm.js:130:14)
    at runScript (/usr/local/lib/node_modules/truffle/build/webpack:/packages/core/lib/console.js:251:1)
    at Console.interpret (/usr/local/lib/node_modules/truffle/build/webpack:/packages/core/lib/console.js:266:1)
    at bound (domain.js:402:14)
    at REPLServer.runBound [as eval] (domain.js:415:12)
    at REPLServer.onLine (repl.js:642:10)
    at REPLServer.emit (events.js:198:13)
    at REPLServer.EventEmitter.emit (domain.js:448:20)
    at REPLServer.Interface._onLine (readline.js:308:10)
    at REPLServer.Interface._line (readline.js:656:8)
    at REPLServer.Interface._ttyWrite (readline.js:937:14)
    at REPLServer.self._ttyWrite (repl.js:715:7)
    at ReadStream.onkeypress (readline.js:184:10)
    at ReadStream.emit (events.js:198:13)
    at ReadStream.EventEmitter.emit (domain.js:448:20)
    at emitKeys (internal/readline.js:424:14)
    at emitKeys.next (<anonymous>)
    at ReadStream.onData (readline.js:1073:36)
    at ReadStream.emit (events.js:198:13)
    at ReadStream.EventEmitter.emit (domain.js:448:20)
    at addChunk (_stream_readable.js:288:12)
    at readableAddChunk (_stream_readable.js:269:11)
    at ReadStream.Readable.push (_stream_readable.js:224:10)
    at TTY.onStreamRead [as onread] (internal/stream_base_commons.js:94:17)
  reason:
   'invalid codepoint at offset 14; unexpected continuation byte',
  code: 'INVALID_ARGUMENT',
  argument: 'bytes',
  value:
   Uint8Array [
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     2,
     85,
     191,
     249,
     11,
     135,
     135,
     240,
     108,
     241,
     58,
     179,
     37,
     153,
     124,
     191,
     59,
     19,
     156,
     29,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     10,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     0,
     4 ],
  baseType: 'string',
  name: null,
  type: 'string',
  hijackedStack:
   'Error: invalid codepoint at offset 14; unexpected continuation byte (argument="bytes", value={"0":0,"1":0,"2":0,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10":0,"11":0,"12":2,"13":

truffle(k8s)> test.currentAddr()
'0x0000000000000000000000000000000000000060'

truffle(k8s)> test.currentInt()
<BN: 255bff90b8787f06cf13ab325997cbf3b139c1d>

Note: The transaction is successful but the sym is set as a byte array and the address and uint256 values are swapped. They are passed in as

[name, new_addr, new_int]

and the function consumes them as

(string memory _sym, address new_addr, uint256 new_int)

however you can see in the above .currentAddr() and .currentInt() that the addr is set as a hex encoded value of 10 and the int is set as a BigNumber conversion of the address.

Note: This function is successful when called directly from truffle

truffle(k8s)> test.setOnlyStringBefore("Name", "0xfe5e669eD4C62A7D4621A604BcC1029171814046", 10)
{ tx:
   '0x1e7f54778810d2ea33b604dc2e1791b05b69540cd77a2357e8572f3f3f580588',
  receipt:
   { blockHash:
      '0x28a3a821daf8b6d8844b330f355ac74e46ee46c900f1be5b748c166357b044c2',
     blockNumber: 878,
     contractAddress: null,
     cumulativeGasUsed: 85007,
     from: '0xfe5e669ed4c62a7d4621a604bcc1029171814046',
     gasUsed: 85007,
     logs: [],
     logsBloom:
      '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
     status: true,
     to: '0x3c7d058ccb934c732674e28b4c45bcc722fb0004',
     transactionHash:
      '0x1e7f54778810d2ea33b604dc2e1791b05b69540cd77a2357e8572f3f3f580588',
     transactionIndex: 0,
     rawLogs: [] },
  logs: [] }

truffle(k8s)> test.sym()

'Name'

truffle(k8s)> test.currentAddr()

'0xfe5e669eD4C62A7D4621A604BcC1029171814046'

truffle(k8s)> test.currentInt()

<BN: a>

---

Scenerio 2

### (Function setOnlyStringAfter) - string is set after address and uint256 in smart contract function parameters

ExW3.Contract.send(:Tester, :setOnlyStringAfter, [10, "0x0255bff90b8787f06cf13ab325997cbf3b139c1d", "name"], %{from: @contracts_owner, gas: 6000000})

{:ok, "0xcb1e0f29d7a0fa5bc7822c2d9302b12cc5a22b02a52323d3ac3bad1a01b64634"}

In Truffle ->

truffle(k8s)> let test = await Tester.deployed()

truffle(k8s)> test.sym()

'' //// <--- Value never got set

truffle(k8s)> web3.eth.getTransactionReceipt("0xcb1e0f29d7a0fa5bc7822c2d9302b12cc5a22b02a52323d3ac3bad1a01b64634")
{ blockHash:
   '0x146459c31989cc9cfe8ae9025c31701566b5a3da14b74f8e69b97bfe4290d983',
  blockNumber: 877,
  contractAddress: null,
  cumulativeGasUsed: 24203,
  from: '0xfe5e669ed4c62a7d4621a604bcc1029171814046',
  gasUsed: '0x5e8b',
  logs: [],
  logsBloom:
   '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000',
  status: false,
  to: '0x3c7d058ccb934c732674e28b4c45bcc722fb0004',
  transactionHash:
   '0xcb1e0f29d7a0fa5bc7822c2d9302b12cc5a22b02a52323d3ac3bad1a01b64634',
  transactionIndex: 0 }

Note: The transaction status is 'false', meaning that the transaction has failed for some reason.

Note: The function call is successful when called from Truffle

[aroyer]

good find fixed in my fork

[gregors]

@aroyer looks like I found that encoding bug again independently see #109