Git-Mirrors/tornado-core
1
0
Fork 0
mirror of https://github.com/tornadocash/tornado-core.git synced 2025-07-20 05:49:01 -04:00
Code Issues Projects Releases Packages Wiki Activity

relayhub protection

Browse source
This commit is contained in:
Alexey 2019-09-26 18:46:49 +03:00
parent dee1c6140a
commit 926a4d7298
4 changed files with 15 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

7
contracts/ETHMixer.sol
View file

@ -34,9 +34,12 @@ contract ETHMixer is GSNMixer {
require(msg.value == mixDenomination, "Please send `mixDenomination` ETH along with transaction");
}
event Debug(uint actualCharge, bytes context, address recipient);
// this func is called by RelayerHub right after calling a target func
function postRelayedCall(bytes memory context, bool /*success*/, uint actualCharge, bytes32 /*preRetVal*/) public onlyHub {
// this require allows to protect againt malicious relay hub that can drain the mixer
require(couldBeWithdrawn, "could be called only after withdrawViaRelayer");
couldBeWithdrawn = false;
IRelayHub relayHub = IRelayHub(getHubAddr());
address payable recipient;
uint256 nullifierHash;
@ -44,10 +47,10 @@ contract ETHMixer is GSNMixer {
recipient := mload(add(context, 32))
nullifierHash := mload(add(context, 64))
}
emit Debug(actualCharge, context, recipient);
recipient.transfer(mixDenomination - actualCharge);
relayHub.depositFor.value(actualCharge)(address(this));
emit Withdraw(recipient, nullifierHash, tx.origin, actualCharge);
}
}

3
contracts/GSNMixer.sol
View file

@ -14,6 +14,7 @@ contract GSNMixer is Mixer, GSNRecipient {
) Mixer(_verifier, _mixDenomination, _merkleTreeHeight, _emptyElement, _operator) public {
}
bool couldBeWithdrawn;
modifier onlyHub() {
require(msg.sender == getHubAddr(), "only relay hub");
_;
@ -27,7 +28,7 @@ contract GSNMixer is Mixer, GSNRecipient {
require(isKnownRoot(root), "Cannot find your merkle root"); // Make sure to use a recent one
require(verifier.verifyProof(a, b, c, input), "Invalid withdraw proof");
nullifierHashes[nullifierHash] = true;
couldBeWithdrawn = true;
// we will process withdraw in postRelayedCall func
}