Feature/pool 245 prizepool needs hard limits on exit fee (#64)

* Set up limits on exit-fee and timelock-duration

* Update test coverage

* Feature/pool 284 update rng service to use rngveedo npm (#65)

* Update to lock block, switch to uint32 (#63)

Update to lock block, switch to uint32

* Update to use published package for RNG

contracts/prize-pool/PrizePool.sol

@@ -41,6 +41,9 @@ abstract contract PrizePool is Initializable, BaseRelayRecipient, ReentrancyGuar
   MappedSinglyLinkedList.Mapping internal _tokens;
   PrizeStrategyInterface public prizeStrategy;
 
+  uint256 internal maxExitFeeMultiple;
+  uint256 internal maxTimelockDuration;
+
   uint256 public timelockTotalSupply;
   mapping(address => uint256) internal timelockBalances;
   mapping(address => uint256) internal unlockTimestamps;
@@ -53,10 +56,14 @@ abstract contract PrizePool is Initializable, BaseRelayRecipient, ReentrancyGuar
   /// @param _trustedForwarder Address of the Forwarding Contract for GSN Meta-Txs
   /// @param _prizeStrategy Address of the component-controller that manages the prize-strategy
   /// @param _controlledTokens Array of addresses for the Ticket and Sponsorship Tokens controlled by the Prize Pool
+  /// @param _maxExitFeeMultiple The maximum exit fee size, relative to the withdrawal amount
+  /// @param _maxTimelockDuration The maximum length of time the withdraw timelock could be
   function initialize (
     address _trustedForwarder,
     PrizeStrategyInterface _prizeStrategy,
-    address[] memory _controlledTokens
+    address[] memory _controlledTokens,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration
   )
     public
     initializer
@@ -74,6 +81,8 @@ abstract contract PrizePool is Initializable, BaseRelayRecipient, ReentrancyGuar
     __ReentrancyGuard_init();
     trustedForwarder = _trustedForwarder;
     prizeStrategy = _prizeStrategy;
+    maxExitFeeMultiple = _maxExitFeeMultiple;
+    maxTimelockDuration = _maxTimelockDuration;
   }
 
   /// @dev Inheriting contract must determine if a specific token type may be awarded as a prize enhancement
@@ -168,6 +177,12 @@ abstract contract PrizePool is Initializable, BaseRelayRecipient, ReentrancyGuar
       exitFee = prizeStrategy.beforeWithdrawInstantlyFrom(from, amount, controlledToken);
     }
 
+    uint256 mantissa = FixedPoint.calculateMantissa(maxExitFeeMultiple, 100);
+    uint256 maxFee = FixedPoint.multiplyUintByMantissa(amount, mantissa);
+    if (exitFee > maxFee) {
+      exitFee = maxFee;
+    }
+
     address operator = _msgSender();
     uint256 sponsoredExitFee = (exitFee > prepaidExitFee) ? prepaidExitFee : exitFee;
     uint256 userExitFee = exitFee.sub(sponsoredExitFee);
@@ -209,13 +224,18 @@ abstract contract PrizePool is Initializable, BaseRelayRecipient, ReentrancyGuar
     onlyControlledToken(controlledToken)
     returns (uint256 unlockTimestamp)
   {
+    uint256 blockTime = _currentTime();
     _updateAwardBalance();
 
     bool hasPrizeStrategy = _hasPrizeStrategy();
     if (hasPrizeStrategy) {
       unlockTimestamp = prizeStrategy.beforeWithdrawWithTimelockFrom(from, amount, controlledToken);
     }
 
+    if (unlockTimestamp > 0 && unlockTimestamp.sub(blockTime) > maxTimelockDuration) {
+      unlockTimestamp = blockTime.add(maxTimelockDuration);
+    }
+
     address operator = _msgSender();
 
     ControlledToken(controlledToken).controllerBurnFrom(operator, from, amount);

contracts/prize-pool/compound/CompoundPrizePool.sol

@@ -20,11 +20,15 @@ contract CompoundPrizePool is PrizePool {
   /// @param _trustedForwarder Address of the Forwarding Contract for GSN Meta-Txs
   /// @param _prizeStrategy Address of the component-controller that manages the prize-strategy
   /// @param _controlledTokens Array of addresses for the Ticket and Sponsorship Tokens controlled by the Prize Pool
+  /// @param _maxExitFeeMultiple The maximum exit fee size, relative to the withdrawal amount
+  /// @param _maxTimelockDuration The maximum length of time the withdraw timelock could be
   /// @param _cToken Address of the Compound cToken interface
   function initialize (
     address _trustedForwarder,
     PrizeStrategyInterface _prizeStrategy,
     address[] memory _controlledTokens,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration,
     CTokenInterface _cToken
   )
     public
@@ -33,7 +37,9 @@ contract CompoundPrizePool is PrizePool {
     PrizePool.initialize(
       _trustedForwarder,
       _prizeStrategy,
-      _controlledTokens
+      _controlledTokens,
+      _maxExitFeeMultiple,
+      _maxTimelockDuration
     );
     cToken = _cToken;
   }

contracts/prize-strategy/PrizeStrategyBuilder.sol

@@ -52,6 +52,8 @@ contract PrizeStrategyBuilder is Initializable {
     bytes memory ticketSymbol,
     bytes memory sponsorshipName,
     bytes memory sponsorshipSymbol,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration,
     address[] memory externalAwards
   ) public returns (PrizeStrategy) {
     PrizeStrategy prizeStrategy = prizeStrategyProxyFactory.create();
@@ -62,7 +64,9 @@ contract PrizeStrategyBuilder is Initializable {
       ticketName,
       ticketSymbol,
       sponsorshipName,
-      sponsorshipSymbol
+      sponsorshipSymbol,
+      _maxExitFeeMultiple,
+      _maxTimelockDuration
     );
 
     prizeStrategy.initialize(
@@ -91,7 +95,9 @@ contract PrizeStrategyBuilder is Initializable {
     bytes memory ticketName,
     bytes memory ticketSymbol,
     bytes memory sponsorshipName,
-    bytes memory sponsorshipSymbol
+    bytes memory sponsorshipSymbol,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration
   ) internal returns (CompoundPrizePool prizePool, address[] memory tokens) {
     prizePool = compoundPrizePoolProxyFactory.create();
     tokens = new address[](2);
@@ -101,6 +107,8 @@ contract PrizeStrategyBuilder is Initializable {
       trustedForwarder,
       prizeStrategy,
       tokens,
+      _maxExitFeeMultiple,
+      _maxTimelockDuration,
       _cToken
     );
   }
@@ -119,7 +127,9 @@ contract PrizeStrategyBuilder is Initializable {
     PrizeStrategy prizeStrategy,
     CTokenInterface _cToken,
     ControlledToken ticket,
-    ControlledToken sponsorship
+    ControlledToken sponsorship,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration
   ) internal returns (CompoundPrizePool) {
     address[] memory tokens = new address[](2);
     tokens[0] = address(ticket);
@@ -129,6 +139,8 @@ contract PrizeStrategyBuilder is Initializable {
       trustedForwarder,
       prizeStrategy,
       tokens,
+      _maxExitFeeMultiple,
+      _maxTimelockDuration,
       _cToken
     );
   }

contracts/prize-strategy/PrizeStrategyStorage.sol

@@ -2,12 +2,12 @@ pragma solidity ^0.6.4;
 
 import "sortition-sum-tree-factory/contracts/SortitionSumTreeFactory.sol";
 import "@pooltogether/governor-contracts/contracts/GovernorInterface.sol";
+import "@pooltogether/pooltogether-rng-contracts/contracts/RNGInterface.sol";
 
 import "../prize-pool/MappedSinglyLinkedList.sol";
 import "../token/TokenControllerInterface.sol";
 import "../token/ControlledToken.sol";
 import "../prize-pool/PrizePool.sol";
-import "../rng/RNGInterface.sol";
 import "../Constants.sol";
 
 contract PrizeStrategyStorage {

contracts/test/CompoundPrizePoolHarness.sol

@@ -7,8 +7,24 @@ contract CompoundPrizePoolHarness is CompoundPrizePool {
 
   uint256 internal time;
 
-  function initialize(CTokenInterface _cToken) public {
-    cToken = _cToken;
+  function initializeAll(
+    address _trustedForwarder,
+    PrizeStrategyInterface _prizeStrategy,
+    address[] memory _controlledTokens,
+    uint256 _maxExitFeeMultiple,
+    uint256 _maxTimelockDuration,
+    CTokenInterface _cToken
+  )
+    public
+  {
+    CompoundPrizePool.initialize(
+      _trustedForwarder,
+      _prizeStrategy,
+      _controlledTokens,
+      _maxExitFeeMultiple,
+      _maxTimelockDuration,
+      _cToken
+    );
   }
 
   function supply(uint256 mintAmount) external {
@@ -23,6 +39,10 @@ contract CompoundPrizePoolHarness is CompoundPrizePool {
     time = _time;
   }
 
+  function setTimelockBalance(uint256 _timelockBalance) external {
+    timelockTotalSupply = _timelockBalance;
+  }
+
   function _currentTime() internal override view returns (uint256) {
     if (time == 0) {
       return block.timestamp;

contracts/test/RNGBlockhash.sol

@@ -2,7 +2,7 @@ pragma solidity ^0.6.4;
 
 import "@openzeppelin/contracts-ethereum-package/contracts/math/SafeMath.sol";
 
-import "../rng/RNGInterface.sol";
+import "@pooltogether/pooltogether-rng-contracts/contracts/RNGInterface.sol";
 
 contract RNGBlockhash is RNGInterface {
   using SafeMath for uint256;

contracts/test/RNGServiceMock.sol

@@ -1,6 +1,6 @@
 pragma solidity ^0.6.4;
 
-import "../rng/RNGInterface.sol";
+import "@pooltogether/pooltogether-rng-contracts/contracts/RNGInterface.sol";
 
 contract RNGServiceMock is RNGInterface {
 

js/deployTestPool.js

@@ -13,7 +13,13 @@ const { deployContract } = require('ethereum-waffle')
 
 const debug = require('debug')('ptv3:deployTestPool')
 
-async function deployTestPool(wallet, prizePeriodSeconds, overrides = { gasLimit: 20000000 }) {
+async function deployTestPool({
+  wallet,
+  prizePeriodSeconds,
+  maxExitFeePercentage,
+  maxTimelockMultiple,
+  overrides = { gasLimit: 20000000 }
+}) {
   let registry = await deploy1820(wallet)
 
   debug('beforeEach deploy rng, forwarder etc...')
@@ -28,7 +34,7 @@ async function deployTestPool(wallet, prizePeriodSeconds, overrides = { gasLimit
   debug('Deploying Governor...')
 
   let governor = await deployContract(wallet, MockGovernor, [], overrides)
-  
+
   debug('Deploying PrizeStrategy...')
 
   let prizeStrategy = await deployContract(wallet, PrizeStrategyHarness, [], overrides)
@@ -49,10 +55,12 @@ async function deployTestPool(wallet, prizePeriodSeconds, overrides = { gasLimit
 
   debug('Initializing CompoundPrizePoolHarness...')
 
-  await compoundPrizePool.initialize(
+  await compoundPrizePool.initializeAll(
     forwarder.address,
     prizeStrategy.address,
     [ticket.address, sponsorship.address],
+    maxExitFeePercentage,
+    prizePeriodSeconds * maxTimelockMultiple,
     cToken.address
   )
 

package.json

@@ -31,8 +31,7 @@
     "prepack": "rm -rf build cache && buidler compile && truffle-extract -b build -o abis",
     "postpublish": "PACKAGE_VERSION=$(./scripts/package-version.sh) && git tag -ae v$PACKAGE_VERSION && git push --tags"
   },
-  "dependencies": {
-  },
+  "dependencies": {},
   "devDependencies": {
     "@nomiclabs/buidler": "^1.3.5",
     "@nomiclabs/buidler-ethers": "^1.3.3",
@@ -44,6 +43,7 @@
     "@pooltogether/fixed-point": "pooltogether/fixed-point.git#0.1.0-upgradeable.1",
     "@pooltogether/governor-contracts": "^0.1.1",
     "@pooltogether/oz-migrate": "^0.2.5",
+    "@pooltogether/pooltogether-rng-contracts": "^3.0.0-alpha.4",
     "@pooltogether/uniform-random-number": "pooltogether/uniform-random-number#solidity-0.6",
     "@resolver-engine/core": "^0.3.3",
     "@truffle/hdwallet-provider": "^1.0.34",