Amm v2 - Exit mode and pool reuse

packages/loopring_v3/contracts/amm/AmplifiedAmmController.sol

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 // Copyright 2017 Loopring Technology Limited.
 pragma solidity ^0.7.0;
+pragma experimental ABIEncoderV2;
 
 import "./IAmmController.sol";
 import "../amm/LoopringAmmPool.sol";
@@ -19,8 +20,14 @@ contract AmplifiedAmmController is IAmmController, Claimable
 
     uint public constant AMPLIFICATION_FACTOR_BASE = (10 ** 18);
 
+    uint public constant MIN_CURVE_CHANGE_DELAY   = 7 days;
+    uint public constant CURVE_CHANGE_AUTH_WINDOW = 7 days;
+
     mapping(address => uint) public amplificationFactors;
 
+    mapping(address => uint) public curveChangeAuthorization;
+
+
     function getInitialVirtualBalances(
         uint96[] memory joinAmounts
         )
@@ -37,44 +44,96 @@ contract AmplifiedAmmController is IAmmController, Claimable
         return vTokenBalancesL2;
     }
 
-    function getVirtualBalances(
-        uint96[] memory tokenBalancesL2,
-        uint96[] memory /*vTokenBalancesL2*/
+   function authorizeVirtualBalances(
+        uint96[] memory balances,
+        uint96[] memory /*vBalancesOld*/,
+        uint96[] memory vBalancesNew,
+        bytes    memory /*data*/
         )
         external
-        view
         override
-        returns (uint96[] memory)
+        returns (bool)
     {
-        // Only allow updating the virtual balances if the AF = 1
-        require(getAmplificationFactor(msg.sender) == AMPLIFICATION_FACTOR_BASE, "INVALID_OPERATION");
+        address pool = msg.sender;
 
-        // Just set the virtual balances to the actual balances
-        uint96[] memory vTokenBalancesL2 = new uint96[](tokenBalancesL2.length);
-        for (uint i = 0; i < tokenBalancesL2.length; i++) {
-            vTokenBalancesL2[i] = tokenBalancesL2[i];
+        // Check if a curve change was explicitly authorized
+        if (consumeCurveChangeAuthorized(pool)) {
+            return true;
         }
-        return vTokenBalancesL2;
+
+        // Special case: Always allow updating the virtual balances if the AF = 1
+        if (getAmplificationFactor(pool) == AMPLIFICATION_FACTOR_BASE) {
+            for (uint i = 0; i < balances.length; i++) {
+                if(vBalancesNew[i] != balances[i]) {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        return false;
+    }
+
+    function authorizeCurveChange(address pool)
+        external
+        onlyOwner
+    {
+        curveChangeAuthorization[pool] = block.timestamp + MIN_CURVE_CHANGE_DELAY;
     }
 
     function setAmplificationFactor(
-        address amm,
+        address pool,
         uint    amplificationFactor
         )
         external
         onlyOwner
     {
-        amplificationFactors[amm] = amplificationFactor;
+        amplificationFactors[pool] = amplificationFactor;
     }
 
-    function getAmplificationFactor(address amm)
+    function getAmplificationFactor(address pool)
         public
         view
         returns (uint amplificationFactor)
     {
-        amplificationFactor = amplificationFactors[amm];
+        amplificationFactor = amplificationFactors[pool];
         if (amplificationFactor == 0) {
             amplificationFactor = AMPLIFICATION_FACTOR_BASE;
         }
     }
+
+    function setupPool(
+        LoopringAmmPool pool,
+        AmmData.PoolConfig calldata config
+        )
+        external
+        onlyOwner
+    {
+        pool.setupPool(config);
+    }
+
+    function enterExitMode(
+        LoopringAmmPool pool,
+        bool enabled
+        )
+        external
+        onlyOwner
+    {
+        pool.enterExitMode(enabled);
+    }
+
+    // == Internal Functions ==
+
+    function consumeCurveChangeAuthorized(address pool)
+        internal
+        returns (bool)
+    {
+        uint timestamp = curveChangeAuthorization[pool];
+        bool authorized = (timestamp <= block.timestamp) && (block.timestamp <= timestamp + MIN_CURVE_CHANGE_DELAY);
+
+        // Remove authorization
+        delete curveChangeAuthorization[pool];
+
+        return authorized;
+    }
 }

packages/loopring_v3/contracts/amm/IAmmController.sol

@@ -18,14 +18,17 @@ interface IAmmController
 
     /// @dev Called by the pool contract when a SET_VIRTUAL_BALANCES operation is done
     ///      on the pool.
-    /// @param tokenBalancesL2 The balances in the pool
-    /// @param vTokenBalancesL2 The current virtual balances in the pool
-    /// @return The new virtual balances in the pool
-    function getVirtualBalances(
-        uint96[] memory tokenBalancesL2,
-        uint96[] memory vTokenBalancesL2
+    /// @param balances The balances in the pool
+    /// @param vBalancesOld The current virtual balances in the pool
+    /// @param vBalancesNew The new virtual balances in the pool
+    /// @param data Custom data
+    /// @return True if vBalancesNew can be used, else false
+    function authorizeVirtualBalances(
+        uint96[] memory balances,
+        uint96[] memory vBalancesOld,
+        uint96[] memory vBalancesNew,
+        bytes    memory data
         )
         external
-        view
-        returns (uint96[] memory);
+        returns (bool);
 }

packages/loopring_v3/contracts/amm/LoopringAmmPool.sol

@@ -79,6 +79,7 @@ contract LoopringAmmPool is
         bool           _joinsDisabled
     )
     {
+        require(_controller != IAmmController(0), "ZERO_ADDRESS");
         controller = _controller;
         assetManager = _assetManager;
         joinsDisabled = _joinsDisabled;
@@ -98,9 +99,17 @@ contract LoopringAmmPool is
         external
         nonReentrant
     {
+        require(state.accountID == 0 || msg.sender == address(controller), "UNAUTHORIZED");
         state.setupPool(config);
     }
 
+    function enterExitMode(bool enabled)
+        external
+        onlyFromController
+    {
+        state.exitMode = enabled;
+    }
+
     // Anyone is able to shut down the pool when requests aren't being processed any more.
     function shutdown(address exitOwner)
         external
@@ -113,7 +122,6 @@ contract LoopringAmmPool is
 
     function shutdownByController()
         external
-        payable
         onlyWhenOnline
         nonReentrant
         onlyFromController

packages/loopring_v3/contracts/amm/libamm/AmmData.sol

@@ -58,6 +58,12 @@ library AmmData
         uint32    validUntil;
     }
 
+    struct PoolVirtualBalances
+    {
+        uint96[]  vBalancesNew;
+        bytes     data;
+    }
+
     struct PoolDeposit
     {
         uint96[]  amounts;
@@ -82,7 +88,8 @@ library AmmData
         uint16  tokenID;
     }
 
-    struct Settings {
+    struct Settings
+    {
         IAmmController controller;
         IAssetManager  assetManager;
         bool           joinsDisabled;
@@ -142,5 +149,6 @@ library AmmData
         mapping (bytes32 => bool) approvedTx;
 
         mapping (address => uint96) balancesL1;
+        bool exitMode;
     }
 }

packages/loopring_v3/contracts/amm/libamm/AmmDepositProcess.sol

@@ -30,11 +30,13 @@ library AmmDepositProcess
     {
         require(poolDeposit.amounts.length == ctx.tokens.length, "INVALID_DEPOSIT_DATA");
         for (uint i = 0; i < ctx.tokens.length; i++) {
-            address token = ctx.tokens[i].addr;
             uint96 amount = poolDeposit.amounts[i];
-            verifyDepositTx(ctx, ctx.tokens[i].tokenID, amount);
-            S.deposit(token, amount);
-            S.balancesL1[token] = S.balancesL1[token].sub(amount);
+            if (amount > 0) {
+                address token = ctx.tokens[i].addr;
+                verifyDepositTx(ctx, ctx.tokens[i].tokenID, amount);
+                S.deposit(token, amount);
+                S.balancesL1[token] = S.balancesL1[token].sub(amount);
+            }
         }
     }
 
@@ -68,7 +70,7 @@ library AmmDepositProcess
             // tokenID == tokenID &&
             packedData & 0xffffffffffffffffffffffffffffffffffffffffffffffffffffff == (uint(ExchangeData.TransactionType.DEPOSIT) << 208) | (uint(address(this)) << 48) | (uint(ctx.accountID) << 16) | uint(tokenID) &&
             amount == txAmount,
-            "INVALID_DEPOSIT_TX_DATA"
+            "INVALID_AMM_DEPOSIT_TX_DATA"
         );
 
         ctx.txsDataPtr += ExchangeData.TX_DATA_AVAILABILITY_SIZE;

packages/loopring_v3/contracts/amm/libamm/AmmExitProcess.sol

@@ -9,26 +9,26 @@ import "../../lib/EIP712.sol";
 import "../../lib/ERC20SafeTransfer.sol";
 import "../../lib/MathUint.sol";
 import "../../lib/MathUint96.sol";
-import "../../lib/SignatureUtil.sol";
 import "../../lib/TransferUtil.sol";
 import "../../thirdparty/SafeCast.sol";
-import "./AmmUtil.sol";
 import "./AmmData.sol";
 import "./AmmExitRequest.sol";
 import "./AmmPoolToken.sol";
+import "./AmmSignature.sol";
+import "./AmmUtil.sol";
 
 
 /// @title AmmExitProcess
 library AmmExitProcess
 {
     using AmmPoolToken      for AmmData.State;
+    using AmmSignature      for bytes32;
     using AmmUtil           for AmmData.Context;
     using AmmUtil           for uint96;
     using ERC20SafeTransfer for address;
     using MathUint          for uint;
     using MathUint96        for uint96;
     using SafeCast          for uint;
-    using SignatureUtil     for bytes32;
     using TransactionReader for ExchangeData.Block;
     using TransferUtil      for address;
 
@@ -49,14 +49,18 @@ library AmmExitProcess
         bool isForcedExit = false;
 
         if (signature.length == 0) {
-            bytes32 forcedExitHash = AmmExitRequest.hash(ctx.domainSeparator, S.forcedExit[exit.owner]);
-            if (txHash == forcedExitHash) {
-                delete S.forcedExit[exit.owner];
-                S.forcedExitCount--;
-                isForcedExit = true;
+            if (S.exitMode) {
+                require(exit.fee == 0, "INVALID_FEE");
             } else {
-                require(S.approvedTx[txHash], "INVALID_ONCHAIN_APPROVAL");
-                delete S.approvedTx[txHash];
+                bytes32 forcedExitHash = AmmExitRequest.hash(ctx.domainSeparator, S.forcedExit[exit.owner]);
+                if (txHash == forcedExitHash) {
+                    delete S.forcedExit[exit.owner];
+                    S.forcedExitCount--;
+                    isForcedExit = true;
+                } else {
+                    require(S.approvedTx[txHash], "INVALID_ONCHAIN_APPROVAL");
+                    delete S.approvedTx[txHash];
+                }
             }
         } else if (signature.length == 1) {
             ctx.verifySignatureL2(exit.owner, txHash, signature);

packages/loopring_v3/contracts/amm/libamm/AmmJoinProcess.sol

@@ -8,25 +8,25 @@ import "../../core/impl/libtransactions/TransferTransaction.sol";
 import "../../lib/EIP712.sol";
 import "../../lib/MathUint.sol";
 import "../../lib/MathUint96.sol";
-import "../../lib/SignatureUtil.sol";
 import "../../thirdparty/SafeCast.sol";
 import "./AmmData.sol";
 import "./AmmJoinRequest.sol";
 import "./AmmPoolToken.sol";
+import "./AmmSignature.sol";
 import "./AmmUtil.sol";
 
 
 /// @title AmmJoinProcess
 library AmmJoinProcess
 {
     using AmmPoolToken      for AmmData.State;
+    using AmmSignature      for bytes32;
     using AmmUtil           for AmmData.State;
     using AmmUtil           for AmmData.Context;
     using AmmUtil           for uint96;
     using MathUint          for uint;
     using MathUint96        for uint96;
     using SafeCast          for uint;
-    using SignatureUtil     for bytes32;
     using TransactionReader for ExchangeData.Block;
 
     // event JoinProcessed(address owner, uint96 mintAmount, uint96[] amounts);

packages/loopring_v3/contracts/amm/libamm/AmmPoolToken.sol

@@ -80,7 +80,7 @@ library AmmPoolToken
         uint256               deadline,
         bytes        calldata signature
         )
-        internal
+        public
     {
         require(deadline >= block.timestamp, 'EXPIRED');
 

packages/loopring_v3/contracts/amm/libamm/AmmSignature.sol

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright 2017 Loopring Technology Limited.
+pragma solidity ^0.7.0;
+pragma experimental ABIEncoderV2;
+
+import "../../lib/SignatureUtil.sol";
+
+
+/// @title AmmSignature
+library AmmSignature
+{
+    using SignatureUtil     for bytes32;
+
+    function verifySignature(
+        bytes32        signHash,
+        address        signer,
+        bytes   memory signature
+        )
+        public
+        view
+        returns (bool)
+    {
+        return signHash.verifySignature(signer, signature);
+    }
+}