delete-TWAP-module

sherlock-audit/2023-12-dodo-gsp-judging#39 sherlock-audit/2023-12-dodo-gsp-judging#80
DODOEX · Jan 9, 2024 · 7462b7e · 7462b7e
1 parent ad9d148
commit 7462b7e
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Showing 7 changed files with 3 additions and 102 deletions.
diff --git a/contracts/GasSavingPool/impl/GSP.sol b/contracts/GasSavingPool/impl/GSP.sol
@@ -29,7 +29,7 @@ contract GSP is GSPTrader, GSPFunding {
      * @param mtFeeRate The rate of mt fee, with 18 decimal
      * @param i The oracle price, possible to be changed only by maintainer
      * @param k The swap curve parameter
-     * @param isOpenTWAP Use TWAP price or not
+     * @param isOpenTWAP Useless, just for compatible
      */
     function init(
         address maintainer,
@@ -64,9 +64,7 @@ contract GSP is GSPTrader, GSPFunding {
         _MT_FEE_RATE_ = mtFeeRate;
         // _MAINTAINER_ is set when initialization, the address receives the fee
         _MAINTAINER_ = maintainer;
-        _IS_OPEN_TWAP_ = isOpenTWAP;
-        // if _IS_OPEN_TWAP_ is true, _BLOCK_TIMESTAMP_LAST_ is set to the current block timestamp
-        if (isOpenTWAP) _BLOCK_TIMESTAMP_LAST_ = uint32(block.timestamp % 2**32);
+        _IS_OPEN_TWAP_ = false; // GSP does not open TWAP by default
 
         string memory connect = "_";
         string memory suffix = "GSP";

diff --git a/contracts/GasSavingPool/impl/GSPStorage.sol b/contracts/GasSavingPool/impl/GSPStorage.sol
@@ -32,10 +32,6 @@ contract GSPStorage is ReentrancyGuard {
     // _BASE_RESERVE_ and _QUOTE_RESERVE_ are the current reserves of the GSP
     uint112 public _BASE_RESERVE_;
     uint112 public _QUOTE_RESERVE_;
-    // _BLOCK_TIMESTAMP_LAST_ is used when calculating TWAP
-    uint32 public _BLOCK_TIMESTAMP_LAST_;
-    // _BASE_PRICE_CUMULATIVE_LAST_ is used when calculating TWAP
-    uint256 public _BASE_PRICE_CUMULATIVE_LAST_;
 
     // _BASE_TARGET_ and _QUOTE_TARGET_ are recalculated when the pool state changes
     uint112 public _BASE_TARGET_;

diff --git a/contracts/GasSavingPool/impl/GSPVault.sol b/contracts/GasSavingPool/impl/GSPVault.sol
@@ -78,19 +78,6 @@ contract GSPVault is GSPStorage {
         return _QUOTE_TOKEN_.balanceOf(address(this)) - uint256(_QUOTE_RESERVE_) - uint256(_MT_FEE_QUOTE_);
     }
 
-    // ============ TWAP UPDATE ===========
-    /**
-     * @notice Update the twap price, internal use only
-     * @dev The twap price is updated when _IS_OPEN_TWAP_ is true
-     */
-    function _twapUpdate() internal {
-        uint32 blockTimestamp = uint32(block.timestamp % 2**32);
-        uint32 timeElapsed = blockTimestamp - _BLOCK_TIMESTAMP_LAST_;
-        if (timeElapsed > 0 && _BASE_RESERVE_ != 0 && _QUOTE_RESERVE_ != 0) {
-            _BASE_PRICE_CUMULATIVE_LAST_ += getMidPrice() * timeElapsed;
-        }
-        _BLOCK_TIMESTAMP_LAST_ = blockTimestamp;
-    }
 
     // ============ Set States ============
     /**
@@ -103,7 +90,6 @@ contract GSPVault is GSPStorage {
         require(baseReserve <= type(uint112).max && quoteReserve <= type(uint112).max, "OVERFLOW");
         _BASE_RESERVE_ = uint112(baseReserve);
         _QUOTE_RESERVE_ = uint112(quoteReserve);
-        if (_IS_OPEN_TWAP_) _twapUpdate();
     }
 
     /**
@@ -121,7 +107,6 @@ contract GSPVault is GSPStorage {
         if (quoteBalance != _QUOTE_RESERVE_) {
             _QUOTE_RESERVE_ = uint112(quoteBalance);
         }
-        if (_IS_OPEN_TWAP_) _twapUpdate();
     }
 
     /// @notice Sync the reserves of the pool

diff --git a/contracts/lib/PMMPricing.sol b/contracts/lib/PMMPricing.sol
@@ -251,16 +251,4 @@ library PMMPricing {
             );
         }
     }
-
-    function getMidPrice(PMMState memory state) internal pure returns (uint256) {
-        if (state.R == RState.BELOW_ONE) {
-            uint256 R = DecimalMath.divFloor(state.Q0 * state.Q0 / state.Q, state.Q);
-            R = DecimalMath.ONE - state.K + (DecimalMath.mulFloor(state.K, R));
-            return DecimalMath.divFloor(state.i, R);
-        } else {
-            uint256 R = DecimalMath.divFloor(state.B0 * state.B0 / state.B, state.B);
-            R = DecimalMath.ONE - state.K + (DecimalMath.mulFloor(state.K, R));
-            return DecimalMath.mulFloor(state.i, R);
-        }
-    }
 }
diff --git a/git b/git
diff --git a/test/GSP.t.sol b/test/GSP.t.sol
@@ -70,51 +70,6 @@ contract TestGSPVault is Test {
         assertEq(sha256(abi.encodePacked(str)), sha256(abi.encodePacked("5615deb7")));
     }
 
-    function testTwapUpdate() public {
-        // set is_open_twap to true
-        address MAINTAINER = 0x95C4F5b83aA70810D4f142d58e5F7242Bd891CB0;
-        address BASE_TOKEN_ADDRESS = DAI;
-        address QUOTE_TOKEN_ADDRESS = USDC;
-        uint256 LP_FEE_RATE = 0;
-        uint256 MT_FEE_RATE = 10000000000000;
-        uint256 I = 1000000;
-        uint256 K = 500000000000000;
-        bool IS_OPEN_TWAP = true;
-        gsp.init(
-            MAINTAINER,
-            BASE_TOKEN_ADDRESS,
-            QUOTE_TOKEN_ADDRESS,
-            LP_FEE_RATE,
-            MT_FEE_RATE,
-            I,
-            K,
-            IS_OPEN_TWAP
-        );
-
-        // transfer some tokens to USER
-        vm.startPrank(DAI_WHALE);
-        dai.transfer(USER, BASE_RESERVE + BASE_INPUT);
-        vm.stopPrank();
-        vm.startPrank(USDC_WHALE);
-        usdc.transfer(USER, QUOTE_RESERVE + QUOTE_INPUT);
-        vm.stopPrank();
-        // User buys shares
-        vm.startPrank(USER);
-        dai.transfer(address(gsp), BASE_RESERVE);
-        usdc.transfer(address(gsp), QUOTE_RESERVE);
-        gsp.buyShares(USER);
-        dai.transfer(address(gsp), BASE_INPUT);
-        gsp.sellBase(USER);
-        uint32 blockTimestampBefore = gsp._BLOCK_TIMESTAMP_LAST_();
-        // Time elapse
-        vm.warp(block.timestamp + 500000);
-        usdc.transfer(address(gsp), QUOTE_INPUT);
-        gsp.sellQuote(USER);
-        uint32 blockTimestampAfter = gsp._BLOCK_TIMESTAMP_LAST_();
-        vm.stopPrank();
-        assertTrue(gsp._IS_OPEN_TWAP_() == true);
-        assertTrue(blockTimestampAfter > blockTimestampBefore);
-    }
 
     function testInitFail() public {
         // Init params

diff --git a/test/PMMPricing.t.sol b/test/PMMPricing.t.sol
@@ -27,15 +27,6 @@ contract PMMPricingTestHelper {
         return (receiveBaseAmount, newR);
 
     }
-
-    function getMidPrice(PMMPricing.PMMState memory state)
-        external
-        pure
-        returns (uint256)
-    {
-        uint256 result = PMMPricing.getMidPrice(state);
-        return result;
-    }
 }
 
 contract PMMPricingTest is Test {
@@ -143,17 +134,4 @@ contract PMMPricingTest is Test {
         assertTrue(newR == PMMPricing.RState.BELOW_ONE);
         assertTrue(receiveBaseAmount == state.B - state.B0);
     }
-
-    function testGetMidPrice() public {
-        state.i = 1e18;
-        state.K = 1e18;
-        state.B = 5e18;
-        state.Q = 5e18;
-        state.B0 = 6e18;
-        state.Q0 = 6e18;
-        uint256 midPrice;
-        state.R = PMMPricing.RState.BELOW_ONE;
-        midPrice = helper.getMidPrice(state);
-        assertEq(midPrice, 694444444444444444);
-    }
 }