Ecrecover function doesn't trigger when called in truffle test

Question

I am trying to run some tests for my ecrecover function. I saw a bunch of tutorials and I always have the same problem, my contract always reverts before anything is being logged.

Contract function

event Test(bytes32 _msgHash, uint8 _v, bytes32 _r, bytes32 _s);
    function registerAddress(address _addr, bytes32 _msgHash, uint8 _v, bytes32 _r, bytes32 _s) public returns (bool) {        
        emit Test(_msgHash, _v, _r, _s);   
        if (_v < 27) _v += 27;
        emit Test(_msgHash, _v, _r, _s);        
        if (_v != 27 && _v != 28) revert();
        emit Test(_msgHash, _v, _r, _s);
        if(ecrecover(_msgHash, _v, _r, _s) != _addr)
        {
            emit Test(_msgHash, _v, _r, _s);
            revert();
        }

        registeredAddresses[_addr] = true;

        emit LogRegisterAddress(_addr);

        return true;
    }

Test Code

it('ecrecover result matches address', async function () {
    var address = owner;
    const message = 'Lorem ipsum mark mark dolor sit amet, consectetur adipiscing elit. Tubulum fuisse, qua illum, cuius is condemnatus est rogatione, P. Eaedem res maneant alio modo.';

    var sig = await generateSignature(address, message);
    var ret = await verifySignature(address, message, sig);

    var result = await coinx.registerAddress.sendTransaction(address, ret.encoded, ret.v, ret.r, ret.s, {from: address});
    assert.equal(result, true);
  });

Functions and some variables

const web3 = new Web3(new Web3.providers.HttpProvider(WEB3_PROVIDER_URL));

var node = web3.version.node.split('/')[0];
console.log('Using node=' + node);
var testrpc = false;
var geth = false;
var parity = false;
if (node === 'Geth') geth = true;
if (node === 'EthereumJS TestRPC') testrpc = true;
if (node === 'Parity') parity = true;



function generateSignature (address, message) {
  console.log('Generating signature');
  console.log('  address=' + address);
  if (testrpc) {
    var encoded = web3.sha3(message);
  }
  if (geth || parity) {
    encoded = '0x' + Buffer.from(message).toString('hex');
  }
  console.log('  encoded message=' + encoded);
  return web3.eth.sign(address, encoded);
}

async function verifySignature (address, message, sig) {
  console.log('Verifying signature');
  console.log('  address=' + address);
  let encoded;

  if (testrpc) {
    encoded = web3.sha3(message);
  } else if (geth || parity) {
    encoded = web3.sha3('\x19Ethereum Signed Message:\n' + message.length + message);
  }
  console.log('  encoded message=' + encoded);
  if (sig.slice(0, 2) === '0x') sig = sig.substr(2);
  if (testrpc || geth) {
    var r = '0x' + sig.substr(0, 64);
    var s = '0x' + sig.substr(64, 64);
    var v = '0x' + sig.substr(128, 2);
  }
  if (parity) {
    v = '0x' + sig.substr(0, 2);
    r = '0x' + sig.substr(2, 64);
    s = '0x' + sig.substr(66, 64);
  }
  console.log('  r: ' + r);
  console.log('  s: ' + s);
  console.log('  v: ' + v);

  var ret = {};
  ret.r = r;
  ret.s = s;
  ret.v = v;
  ret.encoded = encoded;
  return ret;
}

Version:

Truffle v4.1.13 (core: 4.1.13)
Solidity v0.4.24 (solc-js) 
npm v5.4.2 
node v8.7.0

Answer 1

There is a couple of things wrongs.

1- Your encoded message must be

encoded = web3.sha3('\x19Ethereum Signed Message:\n32' + web3.sha3(message))

32 is the length of the hash (sha3(message))

Instead of dealing with complex machine readable string, use other's people library that works ...

const util = require('ethereumjs-util')
encoded = util.hashPersonalMessage(util.toBuffer( web3.sha3(message)))

2- v must be an integer

var v =  web3.toDecimal(sig.substr(128, 2)) + 27

*Full Code *

var SignatureRecover = artifacts.require("SignatureRecover.sol");

const       util            = require('ethereumjs-util'),
            Wallet          = require('ethereumjs-wallet');

contract('SignatureRecover', function(accounts) {

    it('ecrecover result matches address', async function () {
        var address = accounts[0];
        console.log("owner="+address);
        const message = 'Lorem ipsum mark mark dolor sit amet, consectetur adipiscing elit. Tubulum fuisse, qua illum, cuius is condemnatus est rogatione, P. Eaedem res maneant alio modo.';

        var sig = await generateSignature(address, message);
        var ret = await verifySignature(address, message, sig);
        SignatureRecover.deployed().then(function (instance) {
            instance.registerAddress(address, ret.encoded, ret.v, ret.r, ret.s, {from: address}).then(function(tx) {
                console.log(tx.logs);
            });

        });
    });
})

var node = web3.version.node.split('/')[0];
console.log('Using node=' + node);
var testrpc = false;
var geth = false;
var parity = false;
if (node === 'Geth') geth = true;
if (node === 'EthereumJS TestRPC') testrpc = true;
if (node === 'Parity') parity = true;

console.log("testrpc="+testrpc)

function generateSignature (address, message) {
  console.log('Generating signature');
  console.log('  address=' + address);
  if (testrpc) {
    var encoded = web3.sha3(message);
  }
  if (geth || parity) {
    encoded = '0x' + Buffer.from(message).toString('hex');
  }
  console.log('  encoded message=' + encoded);
  return web3.eth.sign(address, encoded);
}

async function verifySignature (address, message, sig) {
  console.log('Verifying signature');
  console.log('  address=' + address);
  let encoded;

  if (testrpc) {
    //encoded = web3.sha3(message);
    encoded = util.hashPersonalMessage(util.toBuffer( web3.sha3(message)))
  } else if (geth || parity) {

    //encoded = web3.sha3('\x19Ethereum Signed Message:\n32' + web3.sha3(message).substr(2));
    encoded = util.hashPersonalMessage(util.toBuffer( web3.sha3(message)))

  }
  console.log('  encoded message=' + encoded.toString('hex'));
  if (sig.slice(0, 2) === '0x') sig = sig.substr(2);
  if (testrpc || geth) {
    var r = '0x' + sig.substr(0, 64);
    var s = '0x' + sig.substr(64, 64);
    var v =  web3.toDecimal(sig.substr(128, 2)) + 27
  }
  if (parity) {
    v = '0x' + sig.substr(0, 2);
    r = '0x' + sig.substr(2, 64);
    s = '0x' + sig.substr(66, 64);
  }
  console.log('  r: ' + r);
  console.log('  s: ' + s);
  console.log('  v: ' + v);

  var ret = {};
  ret.r = r;
  ret.s = s;
  ret.v = v;
  ret.encoded = '0x' + encoded.toString('hex');
  return ret;
}

You can also find all the project on GitHub

i. Run Ganache-cli

$ ganache-cli

ii. Execute Truffle tests

$ truffle test

Compiling ./contracts/Migrations.sol...
Compiling ./contracts/SignatureRecover.sol...
Using node=EthereumJS TestRPC
testrpc=true


  Contract: SignatureRecover
owner=0x7f8b3b04bf34618f4a1723fba96b5db211279a2b
Generating signature
  address=0x7f8b3b04bf34618f4a1723fba96b5db211279a2b
  encoded message=0x067f5bca343172b01203e79581e024f62046b4a935afc81bd1006704a22fbb33
Verifying signature
  address=0x7f8b3b04bf34618f4a1723fba96b5db211279a2b
  encoded message=14431339128bd25f2c7f93baa611e367472048757f4ad67f6d71a5ca0da550f5
  r: 0x51e4dbbbcebade695a3f0fdf10beb8b5f83fda161e1a3105a14c41168bf3dce0
  s: 0x46eabf35680328e26ef4579caf8aeb2cf9ece05dbf67a4f3d1f28c7b1d0e3546
  v: 28
    ✓ ecrecover result matches address (364ms)


  1 passing (440ms)

[ { logIndex: 0,
    transactionIndex: 0,
    transactionHash: '0xe17dcc501eba7efecfd5b0221e5a1f4413648511c69a15d4c296339e02025a4e',
    blockHash: '0x230e806cdecf4a66b84234546261a0675b7c1994ebb64447637ea93c49b49bf6',
    blockNumber: 157,
    address: '0x1f185823be77acab8c093df9190a14293452ae99',
    type: 'mined',
    event: 'Test',
    args: 
     { _msgHash: '0x14431339128bd25f2c7f93baa611e367472048757f4ad67f6d71a5ca0da550f5',
       _v: [Object],
       _r: '0x51e4dbbbcebade695a3f0fdf10beb8b5f83fda161e1a3105a14c41168bf3dce0',
       _s: '0x46eabf35680328e26ef4579caf8aeb2cf9ece05dbf67a4f3d1f28c7b1d0e3546' } },
  { logIndex: 1,
    transactionIndex: 0,
    transactionHash: '0xe17dcc501eba7efecfd5b0221e5a1f4413648511c69a15d4c296339e02025a4e',
    blockHash: '0x230e806cdecf4a66b84234546261a0675b7c1994ebb64447637ea93c49b49bf6',
    blockNumber: 157,
    address: '0x1f185823be77acab8c093df9190a14293452ae99',
    type: 'mined',
    event: 'Test',
    args: 
     { _msgHash: '0x14431339128bd25f2c7f93baa611e367472048757f4ad67f6d71a5ca0da550f5',
       _v: [Object],
       _r: '0x51e4dbbbcebade695a3f0fdf10beb8b5f83fda161e1a3105a14c41168bf3dce0',
       _s: '0x46eabf35680328e26ef4579caf8aeb2cf9ece05dbf67a4f3d1f28c7b1d0e3546' } },
  { logIndex: 2,
    transactionIndex: 0,
    transactionHash: '0xe17dcc501eba7efecfd5b0221e5a1f4413648511c69a15d4c296339e02025a4e',
    blockHash: '0x230e806cdecf4a66b84234546261a0675b7c1994ebb64447637ea93c49b49bf6',
    blockNumber: 157,
    address: '0x1f185823be77acab8c093df9190a14293452ae99',
    type: 'mined',
    event: 'Test',
    args: 
     { _msgHash: '0x14431339128bd25f2c7f93baa611e367472048757f4ad67f6d71a5ca0da550f5',
       _v: [Object],
       _r: '0x51e4dbbbcebade695a3f0fdf10beb8b5f83fda161e1a3105a14c41168bf3dce0',
       _s: '0x46eabf35680328e26ef4579caf8aeb2cf9ece05dbf67a4f3d1f28c7b1d0e3546' } },
  { logIndex: 3,
    transactionIndex: 0,
    transactionHash: '0xe17dcc501eba7efecfd5b0221e5a1f4413648511c69a15d4c296339e02025a4e',
    blockHash: '0x230e806cdecf4a66b84234546261a0675b7c1994ebb64447637ea93c49b49bf6',
    blockNumber: 157,
    address: '0x1f185823be77acab8c093df9190a14293452ae99',
    type: 'mined',
    event: 'LogRegisterAddress',
    args: { _addr: '0x7f8b3b04bf34618f4a1723fba96b5db211279a2b' } } ]