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Contract Diff Checker

Contract Name:
RollupUserFacet

Contract Source Code:

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// SPDX-License-Identifier: Apache-2.0

pragma solidity ^0.6.11;

import "../Rollup.sol";
import "./IRollupFacets.sol";
import { NitroReadyMagicNums } from "../../bridge/NitroMigratorUtil.sol";

abstract contract AbsRollupUserFacet is RollupBase, IRollupUser {
    function initialize(address _stakeToken) public virtual override;

    modifier onlyValidator() {
        require(isValidator[msg.sender], "NOT_VALIDATOR");
        _;
    }

    /**
     * @notice Reject the next unresolved node
     * @param stakerAddress Example staker staked on sibling, used to prove a node is on an unconfirmable branch and can be rejected
     */
    function rejectNextNode(address stakerAddress) external onlyValidator whenNotPaused {
        requireUnresolvedExists();
        uint256 latestConfirmedNodeNum = latestConfirmed();
        uint256 firstUnresolvedNodeNum = firstUnresolvedNode();
        INode firstUnresolvedNode_ = getNode(firstUnresolvedNodeNum);

        if (firstUnresolvedNode_.prev() == latestConfirmedNodeNum) {
            /**If the first unresolved node is a child of the latest confirmed node, to prove it can be rejected, we show:
             * a) Its deadline has expired
             * b) *Some* staker is staked on a sibling

             * The following three checks are sufficient to prove b:
            */

            // 1.  StakerAddress is indeed a staker
            require(isStaked(stakerAddress), "NOT_STAKED");

            // 2. Staker's latest staked node hasn't been resolved; this proves that staker's latest staked node can't be a parent of firstUnresolvedNode
            requireUnresolved(latestStakedNode(stakerAddress));

            // 3. staker isn't staked on first unresolved node; this proves staker's latest staked can't be a child of firstUnresolvedNode (recall staking on node requires staking on all of its parents)
            require(!firstUnresolvedNode_.stakers(stakerAddress), "STAKED_ON_TARGET");
            // If a staker is staked on a node that is neither a child nor a parent of firstUnresolvedNode, it must be a sibling, QED

            // Verify the block's deadline has passed
            firstUnresolvedNode_.requirePastDeadline();

            getNode(latestConfirmedNodeNum).requirePastChildConfirmDeadline();

            removeOldZombies(0);

            // Verify that no staker is staked on this node
            require(
                firstUnresolvedNode_.stakerCount() == countStakedZombies(firstUnresolvedNode_),
                "HAS_STAKERS"
            );
        }
        // Simpler case: if the first unreseolved node doesn't point to the last confirmed node, another branch was confirmed and can simply reject it outright
        _rejectNextNode();
        rollupEventBridge.nodeRejected(firstUnresolvedNodeNum);

        emit NodeRejected(firstUnresolvedNodeNum);
    }

    /**
     * @notice Confirm the next unresolved node
     * @param beforeSendAcc Accumulator of the AVM sends from the beginning of time up to the end of the previous confirmed node
     * @param sendsData Concatenated data of the sends included in the confirmed node
     * @param sendLengths Lengths of the included sends
     * @param afterSendCount Total number of AVM sends emitted from the beginning of time after this node is confirmed
     * @param afterLogAcc Accumulator of the AVM logs from the beginning of time up to the end of this node
     * @param afterLogCount Total number of AVM logs emitted from the beginning of time after this node is confirmed
     */
    function confirmNextNode(
        bytes32 beforeSendAcc,
        bytes calldata sendsData,
        uint256[] calldata sendLengths,
        uint256 afterSendCount,
        bytes32 afterLogAcc,
        uint256 afterLogCount
    ) external onlyValidator whenInShutdownModeOrNotPaused {
        requireUnresolvedExists();

        // There is at least one non-zombie staker
        require(stakerCount() > 0, "NO_STAKERS");

        INode node = getNode(firstUnresolvedNode());

        // Verify the block's deadline has passed
        node.requirePastDeadline();
        getNode(latestConfirmed()).requirePastChildConfirmDeadline();

        // Check that prev is latest confirmed
        require(node.prev() == latestConfirmed(), "INVALID_PREV");

        removeOldZombies(0);

        // All non-zombie stakers are staked on this node
        require(
            node.stakerCount() == stakerCount().add(countStakedZombies(node)),
            "NOT_ALL_STAKED"
        );

        confirmNextNode(
            beforeSendAcc,
            sendsData,
            sendLengths,
            afterSendCount,
            afterLogAcc,
            afterLogCount,
            outbox,
            rollupEventBridge
        );
    }

    /**
     * @notice Create a new stake
     * @param depositAmount The amount of either eth or tokens staked
     */
    function _newStake(uint256 depositAmount) internal onlyValidator whenNotPaused {
        // Verify that sender is not already a staker
        require(!isStaked(msg.sender), "ALREADY_STAKED");
        require(!isZombie(msg.sender), "STAKER_IS_ZOMBIE");
        require(depositAmount >= currentRequiredStake(), "NOT_ENOUGH_STAKE");

        createNewStake(msg.sender, depositAmount);

        rollupEventBridge.stakeCreated(msg.sender, latestConfirmed());
    }

    /**
     * @notice Move stake onto existing child node
     * @param nodeNum Index of the node to move stake to. This must by a child of the node the staker is currently staked on
     * @param nodeHash Node hash of nodeNum (protects against reorgs)
     */
    function stakeOnExistingNode(uint256 nodeNum, bytes32 nodeHash)
        external
        onlyValidator
        whenNotPaused
    {
        require(isStaked(msg.sender), "NOT_STAKED");

        require(getNodeHash(nodeNum) == nodeHash, "NODE_REORG");
        require(
            nodeNum >= firstUnresolvedNode() && nodeNum <= latestNodeCreated(),
            "NODE_NUM_OUT_OF_RANGE"
        );
        INode node = getNode(nodeNum);
        require(latestStakedNode(msg.sender) == node.prev(), "NOT_STAKED_PREV");
        stakeOnNode(msg.sender, nodeNum, confirmPeriodBlocks);
    }

    /**
     * @notice Create a new node and move stake onto it
     * @param expectedNodeHash The hash of the node being created (protects against reorgs)
     * @param assertionBytes32Fields Assertion data for creating
     * @param assertionIntFields Assertion data for creating
     * @param beforeProposedBlock Block number at previous assertion
     * @param beforeInboxMaxCount Inbox count at previous assertion
     * @param sequencerBatchProof Proof data for ensuring expected state of inbox (used in Nodehash to protect against reorgs)
     */
    function stakeOnNewNode(
        bytes32 expectedNodeHash,
        bytes32[3][2] calldata assertionBytes32Fields,
        uint256[4][2] calldata assertionIntFields,
        uint256 beforeProposedBlock,
        uint256 beforeInboxMaxCount,
        bytes calldata sequencerBatchProof
    ) external onlyValidator whenNotPaused {
        require(isStaked(msg.sender), "NOT_STAKED");

        RollupLib.Assertion memory assertion = RollupLib.decodeAssertion(
            assertionBytes32Fields,
            assertionIntFields,
            beforeProposedBlock,
            beforeInboxMaxCount,
            sequencerBridge.messageCount()
        );

        {
            uint256 timeSinceLastNode = block.number.sub(assertion.beforeState.proposedBlock);
            // Verify that assertion meets the minimum Delta time requirement
            require(timeSinceLastNode >= minimumAssertionPeriod, "TIME_DELTA");

            uint256 gasUsed = RollupLib.assertionGasUsed(assertion);
            // Minimum size requirements: each assertion must satisfy either
            require(
                // Consumes at least all inbox messages put into L1 inbox before your prev node’s L1 blocknum
                assertion.afterState.inboxCount >= assertion.beforeState.inboxMaxCount ||
                    // Consumes AvmGas >=100% of speed limit for time since your prev node (based on difference in L1 blocknum)
                    gasUsed >= timeSinceLastNode.mul(avmGasSpeedLimitPerBlock) ||
                    assertion.afterState.sendCount.sub(assertion.beforeState.sendCount) ==
                    MAX_SEND_COUNT,
                "TOO_SMALL"
            );

            // Don't allow an assertion to include more than the maxiumum number of sends
            require(
                assertion.afterState.sendCount.sub(assertion.beforeState.sendCount) <=
                    MAX_SEND_COUNT,
                "TOO_MANY_SENDS"
            );

            // Don't allow an assertion to use above a maximum amount of gas
            require(gasUsed <= timeSinceLastNode.mul(avmGasSpeedLimitPerBlock).mul(4), "TOO_LARGE");
        }
        createNewNode(
            assertion,
            assertionBytes32Fields,
            assertionIntFields,
            sequencerBatchProof,
            CreateNodeDataFrame({
                avmGasSpeedLimitPerBlock: avmGasSpeedLimitPerBlock,
                confirmPeriodBlocks: confirmPeriodBlocks,
                prevNode: latestStakedNode(msg.sender), // Ensure staker is staked on the previous node
                sequencerInbox: sequencerBridge,
                rollupEventBridge: rollupEventBridge,
                nodeFactory: nodeFactory
            }),
            expectedNodeHash
        );

        stakeOnNode(msg.sender, latestNodeCreated(), confirmPeriodBlocks);
    }

    /**
     * @notice Refund a staker that is currently staked on or before the latest confirmed node
     * @dev Since a staker is initially placed in the latest confirmed node, if they don't move it
     * a griefer can remove their stake. It is recomended to batch together the txs to place a stake
     * and move it to the desired node.
     * @param stakerAddress Address of the staker whose stake is refunded
     */
    function returnOldDeposit(address stakerAddress)
        external
        override
        onlyValidator
        whenInShutdownModeOrNotPaused
    {
        require(latestStakedNode(stakerAddress) <= latestConfirmed(), "TOO_RECENT");
        requireUnchallengedStaker(stakerAddress);
        withdrawStaker(stakerAddress);
    }

    /**
     * @notice Increase the amount staked for the given staker
     * @param stakerAddress Address of the staker whose stake is increased
     * @param depositAmount The amount of either eth or tokens deposited
     */
    function _addToDeposit(address stakerAddress, uint256 depositAmount)
        internal
        onlyValidator
        whenNotPaused
    {
        requireUnchallengedStaker(stakerAddress);
        increaseStakeBy(stakerAddress, depositAmount);
    }

    /**
     * @notice Reduce the amount staked for the sender (difference between initial amount staked and target is creditted back to the sender).
     * @param target Target amount of stake for the staker. If this is below the current minimum, it will be set to minimum instead
     */
    function reduceDeposit(uint256 target) external onlyValidator whenNotPaused {
        requireUnchallengedStaker(msg.sender);
        uint256 currentRequired = currentRequiredStake();
        if (target < currentRequired) {
            target = currentRequired;
        }
        reduceStakeTo(msg.sender, target);
    }

    /**
     * @notice Start a challenge between the given stakers over the node created by the first staker assuming that the two are staked on conflicting nodes. N.B.: challenge creator does not necessarily need to be one of the two asserters.
     * @param stakers Stakers engaged in the challenge. The first staker should be staked on the first node
     * @param nodeNums Nodes of the stakers engaged in the challenge. The first node should be the earliest and is the one challenged
     * @param executionHashes Challenge related data for the two nodes
     * @param proposedTimes Times that the two nodes were proposed
     * @param maxMessageCounts Total number of messages consumed by the two nodes
     */
    function createChallenge(
        address payable[2] calldata stakers,
        uint256[2] calldata nodeNums,
        bytes32[2] calldata executionHashes,
        uint256[2] calldata proposedTimes,
        uint256[2] calldata maxMessageCounts
    ) external onlyValidator whenNotPaused {
        require(nodeNums[0] < nodeNums[1], "WRONG_ORDER");
        require(nodeNums[1] <= latestNodeCreated(), "NOT_PROPOSED");
        require(latestConfirmed() < nodeNums[0], "ALREADY_CONFIRMED");

        INode node1 = getNode(nodeNums[0]);
        INode node2 = getNode(nodeNums[1]);

        // ensure nodes staked on the same parent (and thus in conflict)
        require(node1.prev() == node2.prev(), "DIFF_PREV");

        // ensure both stakers aren't currently in challenge
        requireUnchallengedStaker(stakers[0]);
        requireUnchallengedStaker(stakers[1]);

        require(node1.stakers(stakers[0]), "STAKER1_NOT_STAKED");
        require(node2.stakers(stakers[1]), "STAKER2_NOT_STAKED");

        // Check param data against challenge hash
        require(
            node1.challengeHash() ==
                RollupLib.challengeRootHash(
                    executionHashes[0],
                    proposedTimes[0],
                    maxMessageCounts[0]
                ),
            "CHAL_HASH1"
        );

        require(
            node2.challengeHash() ==
                RollupLib.challengeRootHash(
                    executionHashes[1],
                    proposedTimes[1],
                    maxMessageCounts[1]
                ),
            "CHAL_HASH2"
        );

        // Calculate upper limit for allowed node proposal time:
        uint256 commonEndTime = getNode(node1.prev()).firstChildBlock().add( // Dispute start: dispute timer for a node starts when its first child is created
            node1.deadlineBlock().sub(proposedTimes[0]).add(extraChallengeTimeBlocks) // add dispute window to dispute start time
        );
        if (commonEndTime < proposedTimes[1]) {
            // The 2nd node was created too late; loses challenge automatically.
            completeChallengeImpl(stakers[0], stakers[1]);
            return;
        }
        // Start a challenge between staker1 and staker2. Staker1 will defend the correctness of node1, and staker2 will challenge it.
        address challengeAddress = challengeFactory.createChallenge(
            address(this),
            executionHashes[0],
            maxMessageCounts[0],
            stakers[0],
            stakers[1],
            commonEndTime.sub(proposedTimes[0]),
            commonEndTime.sub(proposedTimes[1]),
            sequencerBridge,
            delayedBridge
        ); // trusted external call

        challengeStarted(stakers[0], stakers[1], challengeAddress);

        emit RollupChallengeStarted(challengeAddress, stakers[0], stakers[1], nodeNums[0]);
    }

    /**
     * @notice Inform the rollup that the challenge between the given stakers is completed
     * @param winningStaker Address of the winning staker
     * @param losingStaker Address of the losing staker
     */
    function completeChallenge(address winningStaker, address losingStaker)
        external
        override
        whenNotPaused
    {
        // Only the challenge contract can call this to declare the winner and loser
        require(msg.sender == inChallenge(winningStaker, losingStaker), "WRONG_SENDER");

        completeChallengeImpl(winningStaker, losingStaker);
    }

    function completeChallengeImpl(address winningStaker, address losingStaker) private {
        uint256 remainingLoserStake = amountStaked(losingStaker);
        uint256 winnerStake = amountStaked(winningStaker);
        if (remainingLoserStake > winnerStake) {
            // If loser has a higher stake than the winner, refund the difference
            remainingLoserStake = remainingLoserStake.sub(reduceStakeTo(losingStaker, winnerStake));
        }

        // Reward the winner with half the remaining stake
        uint256 amountWon = remainingLoserStake / 2;
        increaseStakeBy(winningStaker, amountWon);
        remainingLoserStake = remainingLoserStake.sub(amountWon);
        clearChallenge(winningStaker);
        // Credit the other half to the owner address
        increaseWithdrawableFunds(owner, remainingLoserStake);
        // Turning loser into zombie renders the loser's remaining stake inaccessible
        turnIntoZombie(losingStaker);
    }

    /**
     * @notice Remove the given zombie from nodes it is staked on, moving backwords from the latest node it is staked on
     * @param zombieNum Index of the zombie to remove
     * @param maxNodes Maximum number of nodes to remove the zombie from (to limit the cost of this transaction)
     */
    function removeZombie(uint256 zombieNum, uint256 maxNodes)
        external
        onlyValidator
        whenNotPaused
    {
        require(zombieNum <= zombieCount(), "NO_SUCH_ZOMBIE");
        address zombieStakerAddress = zombieAddress(zombieNum);
        uint256 latestNodeStaked = zombieLatestStakedNode(zombieNum);
        uint256 nodesRemoved = 0;
        uint256 firstUnresolved = firstUnresolvedNode();
        while (latestNodeStaked >= firstUnresolved && nodesRemoved < maxNodes) {
            INode node = getNode(latestNodeStaked);
            node.removeStaker(zombieStakerAddress);
            latestNodeStaked = node.prev();
            nodesRemoved++;
        }
        if (latestNodeStaked < firstUnresolved) {
            removeZombie(zombieNum);
        } else {
            zombieUpdateLatestStakedNode(zombieNum, latestNodeStaked);
        }
    }

    /**
     * @notice Remove any zombies whose latest stake is earlier than the first unresolved node
     * @param startIndex Index in the zombie list to start removing zombies from (to limit the cost of this transaction)
     */
    function removeOldZombies(uint256 startIndex)
        public
        onlyValidator
        whenInShutdownModeOrNotPaused
    {
        uint256 currentZombieCount = zombieCount();
        uint256 firstUnresolved = firstUnresolvedNode();
        for (uint256 i = startIndex; i < currentZombieCount; i++) {
            while (zombieLatestStakedNode(i) < firstUnresolved) {
                removeZombie(i);
                currentZombieCount--;
                if (i >= currentZombieCount) {
                    return;
                }
            }
        }
    }

    /**
     * @notice Calculate the current amount of funds required to place a new stake in the rollup
     * @dev If the stake requirement get's too high, this function may start reverting due to overflow, but
     * that only blocks operations that should be blocked anyway
     * @return The current minimum stake requirement
     */
    function currentRequiredStake(
        uint256 _blockNumber,
        uint256 _firstUnresolvedNodeNum,
        uint256 _latestCreatedNode
    ) internal view returns (uint256) {
        // If there are no unresolved nodes, then you can use the base stake
        if (_firstUnresolvedNodeNum - 1 == _latestCreatedNode) {
            return baseStake;
        }
        uint256 firstUnresolvedDeadline = getNode(_firstUnresolvedNodeNum).deadlineBlock();
        if (_blockNumber < firstUnresolvedDeadline) {
            return baseStake;
        }
        uint24[10] memory numerators = [
            1,
            122971,
            128977,
            80017,
            207329,
            114243,
            314252,
            129988,
            224562,
            162163
        ];
        uint24[10] memory denominators = [
            1,
            114736,
            112281,
            64994,
            157126,
            80782,
            207329,
            80017,
            128977,
            86901
        ];
        uint256 firstUnresolvedAge = _blockNumber.sub(firstUnresolvedDeadline);
        uint256 periodsPassed = firstUnresolvedAge.mul(10).div(confirmPeriodBlocks);
        // Overflow check
        if (periodsPassed.div(10) >= 255) {
            return type(uint256).max;
        }
        uint256 baseMultiplier = 2**periodsPassed.div(10);
        uint256 withNumerator = baseMultiplier * numerators[periodsPassed % 10];
        // Overflow check
        if (withNumerator / baseMultiplier != numerators[periodsPassed % 10]) {
            return type(uint256).max;
        }
        uint256 multiplier = withNumerator.div(denominators[periodsPassed % 10]);
        if (multiplier == 0) {
            multiplier = 1;
        }
        uint256 fullStake = baseStake * multiplier;
        // Overflow check
        if (fullStake / baseStake != multiplier) {
            return type(uint256).max;
        }
        return fullStake;
    }

    /**
     * @notice Calculate the current amount of funds required to place a new stake in the rollup
     * @dev If the stake requirement get's too high, this function may start reverting due to overflow, but
     * that only blocks operations that should be blocked anyway
     * @return The current minimum stake requirement
     */
    function requiredStake(
        uint256 blockNumber,
        uint256 firstUnresolvedNodeNum,
        uint256 latestCreatedNode
    ) external view returns (uint256) {
        return currentRequiredStake(blockNumber, firstUnresolvedNodeNum, latestCreatedNode);
    }

    function currentRequiredStake() public view returns (uint256) {
        uint256 firstUnresolvedNodeNum = firstUnresolvedNode();

        return currentRequiredStake(block.number, firstUnresolvedNodeNum, latestNodeCreated());
    }

    /**
     * @notice Calculate the number of zombies staked on the given node
     *
     * @dev This function could be uncallable if there are too many zombies. However,
     * removeZombie and removeOldZombies can be used to remove any zombies that exist
     * so that this will then be callable
     *
     * @param node The node on which to count staked zombies
     * @return The number of zombies staked on the node
     */
    function countStakedZombies(INode node) public view override returns (uint256) {
        uint256 currentZombieCount = zombieCount();
        uint256 stakedZombieCount = 0;
        for (uint256 i = 0; i < currentZombieCount; i++) {
            if (node.stakers(zombieAddress(i))) {
                stakedZombieCount++;
            }
        }
        return stakedZombieCount;
    }

    /**
     * @notice Verify that there are some number of nodes still unresolved
     */
    function requireUnresolvedExists() public view override {
        uint256 firstUnresolved = firstUnresolvedNode();
        require(
            firstUnresolved > latestConfirmed() && firstUnresolved <= latestNodeCreated(),
            "NO_UNRESOLVED"
        );
    }

    function requireUnresolved(uint256 nodeNum) public view override {
        require(nodeNum >= firstUnresolvedNode(), "ALREADY_DECIDED");
        require(nodeNum <= latestNodeCreated(), "DOESNT_EXIST");
    }

    /**
     * @notice Verify that the given address is staked and not actively in a challenge
     * @param stakerAddress Address to check
     */
    function requireUnchallengedStaker(address stakerAddress) private view {
        require(isStaked(stakerAddress), "NOT_STAKED");
        require(currentChallenge(stakerAddress) == address(0), "IN_CHAL");
    }

    function isNitroReady() external pure returns (uint256) {
        return NitroReadyMagicNums.ROLLUP_USER;
    }

    function withdrawStakerFunds(address payable destination) external virtual returns (uint256);
}

contract RollupUserFacet is AbsRollupUserFacet {
    function initialize(address _stakeToken) public override {
        require(_stakeToken == address(0), "NO_TOKEN_ALLOWED");
        // stakeToken = _stakeToken;
    }

    /**
     * @notice Create a new stake
     * @dev It is recomended to call stakeOnExistingNode after creating a new stake
     * so that a griefer doesn't remove your stake by immediately calling returnOldDeposit
     */
    function newStake() external payable onlyValidator whenNotPaused {
        _newStake(msg.value);
    }

    /**
     * @notice Increase the amount staked eth for the given staker
     * @param stakerAddress Address of the staker whose stake is increased
     */
    function addToDeposit(address stakerAddress) external payable onlyValidator whenNotPaused {
        _addToDeposit(stakerAddress, msg.value);
    }

    /**
     * @notice Withdraw uncomitted funds owned by sender from the rollup chain
     * @param destination Address to transfer the withdrawn funds to
     */
    function withdrawStakerFunds(address payable destination)
        external
        override
        onlyValidator
        whenInShutdownModeOrNotPaused
        returns (uint256)
    {
        uint256 amount = withdrawFunds(msg.sender);
        // This is safe because it occurs after all checks and effects
        destination.transfer(amount);
        return amount;
    }
}

contract ERC20RollupUserFacet is AbsRollupUserFacet {
    function initialize(address _stakeToken) public override {
        require(_stakeToken != address(0), "NEED_STAKE_TOKEN");
        require(stakeToken == address(0), "ALREADY_INIT");
        stakeToken = _stakeToken;
    }

    /**
     * @notice Create a new stake
     * @dev It is recomended to call stakeOnExistingNode after creating a new stake
     * so that a griefer doesn't remove your stake by immediately calling returnOldDeposit
     * @param tokenAmount the amount of tokens staked
     */
    function newStake(uint256 tokenAmount) external onlyValidator whenNotPaused {
        _newStake(tokenAmount);
        require(
            IERC20(stakeToken).transferFrom(msg.sender, address(this), tokenAmount),
            "TRANSFER_FAIL"
        );
    }

    /**
     * @notice Increase the amount staked tokens for the given staker
     * @param stakerAddress Address of the staker whose stake is increased
     * @param tokenAmount the amount of tokens staked
     */
    function addToDeposit(address stakerAddress, uint256 tokenAmount)
        external
        onlyValidator
        whenNotPaused
    {
        _addToDeposit(stakerAddress, tokenAmount);
        require(
            IERC20(stakeToken).transferFrom(msg.sender, address(this), tokenAmount),
            "TRANSFER_FAIL"
        );
    }

    /**
     * @notice Withdraw uncomitted funds owned by sender from the rollup chain
     * @param destination Address to transfer the withdrawn funds to
     */
    function withdrawStakerFunds(address payable destination)
        external
        override
        onlyValidator
        whenInShutdownModeOrNotPaused
        returns (uint256)
    {
        uint256 amount = withdrawFunds(msg.sender);
        // This is safe because it occurs after all checks and effects
        require(IERC20(stakeToken).transfer(destination, amount), "TRANSFER_FAILED");
        return amount;
    }
}

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// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "@openzeppelin/contracts/utils/Pausable.sol";
import "@openzeppelin/contracts/proxy/Proxy.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

import "./RollupEventBridge.sol";
import "./RollupCore.sol";
import "./RollupLib.sol";
import "./INode.sol";
import "./INodeFactory.sol";

import "../challenge/IChallenge.sol";
import "../challenge/IChallengeFactory.sol";

import "../bridge/interfaces/IBridge.sol";
import "../bridge/interfaces/IOutbox.sol";
import "../bridge/Messages.sol";

import "../libraries/ProxyUtil.sol";
import "../libraries/Cloneable.sol";
import "./facets/IRollupFacets.sol";

abstract contract RollupBase is Cloneable, RollupCore, Pausable {
    // Rollup Config
    uint256 public confirmPeriodBlocks;
    uint256 public extraChallengeTimeBlocks;
    uint256 public avmGasSpeedLimitPerBlock;
    uint256 public baseStake;

    // Bridge is an IInbox and IOutbox
    IBridge public delayedBridge;
    ISequencerInbox public sequencerBridge;
    IOutbox public outbox;
    RollupEventBridge public rollupEventBridge;
    IChallengeFactory public challengeFactory;
    INodeFactory public nodeFactory;
    address public owner;
    address public stakeToken;
    uint256 public minimumAssertionPeriod;

    uint256 public STORAGE_GAP_1;
    uint256 public STORAGE_GAP_2;
    uint256 public challengeExecutionBisectionDegree;

    address[] internal facets;

    mapping(address => bool) isValidator;

    /// @dev indicates the block which the rollup starts the shutdown for nitro mode
    uint256 public shutdownForNitroBlock;

    /// @dev indicates if rollup is in shutdown for nitro mode
    function shutdownForNitroMode() public view returns (bool) {
        return block.number >= shutdownForNitroBlock;
    }

    /// @dev allows a function to be executed either if contract is either in `shutdownForNitroMode` or not paused
    modifier whenInShutdownModeOrNotPaused() {
        if (!shutdownForNitroMode()) {
            require(!paused(), "Pausable: paused");
        }
        _;
    }

    /// @notice DEPRECATED -- this method is deprecated but still mantained for backward compatibility
    /// @dev this actually returns the avmGasSpeedLimitPerBlock
    /// @return this actually returns the avmGasSpeedLimitPerBlock
    function arbGasSpeedLimitPerBlock() external view returns (uint256) {
        return avmGasSpeedLimitPerBlock;
    }
}

contract Rollup is Proxy, RollupBase {
    using Address for address;

    constructor(uint256 _confirmPeriodBlocks) public Cloneable() Pausable() {
        // constructor is used so logic contract can't be init'ed
        confirmPeriodBlocks = _confirmPeriodBlocks;
        require(isInit(), "CONSTRUCTOR_NOT_INIT");
    }

    function isInit() internal view returns (bool) {
        return confirmPeriodBlocks != 0;
    }

    // _rollupParams = [ confirmPeriodBlocks, extraChallengeTimeBlocks, avmGasSpeedLimitPerBlock, baseStake ]
    // connectedContracts = [delayedBridge, sequencerInbox, outbox, rollupEventBridge, challengeFactory, nodeFactory]
    function initialize(
        bytes32 _machineHash,
        uint256[4] calldata _rollupParams,
        address _stakeToken,
        address _owner,
        bytes calldata _extraConfig,
        address[6] calldata connectedContracts,
        address[2] calldata _facets,
        uint256[2] calldata sequencerInboxParams
    ) public {
        require(!isInit(), "ALREADY_INIT");

        // calls initialize method in user facet
        require(_facets[0].isContract(), "FACET_0_NOT_CONTRACT");
        require(_facets[1].isContract(), "FACET_1_NOT_CONTRACT");
        (bool success, ) = _facets[1].delegatecall(
            abi.encodeWithSelector(IRollupUser.initialize.selector, _stakeToken)
        );
        require(success, "FAIL_INIT_FACET");

        delayedBridge = IBridge(connectedContracts[0]);
        sequencerBridge = ISequencerInbox(connectedContracts[1]);
        outbox = IOutbox(connectedContracts[2]);
        delayedBridge.setOutbox(connectedContracts[2], true);
        rollupEventBridge = RollupEventBridge(connectedContracts[3]);
        delayedBridge.setInbox(connectedContracts[3], true);

        rollupEventBridge.rollupInitialized(
            _rollupParams[0],
            _rollupParams[2],
            _owner,
            _extraConfig
        );

        challengeFactory = IChallengeFactory(connectedContracts[4]);
        nodeFactory = INodeFactory(connectedContracts[5]);

        INode node = createInitialNode(_machineHash);
        initializeCore(node);

        confirmPeriodBlocks = _rollupParams[0];
        extraChallengeTimeBlocks = _rollupParams[1];
        avmGasSpeedLimitPerBlock = _rollupParams[2];
        baseStake = _rollupParams[3];
        owner = _owner;
        // A little over 15 minutes
        minimumAssertionPeriod = 75;
        challengeExecutionBisectionDegree = 400;

        sequencerBridge.setMaxDelay(sequencerInboxParams[0], sequencerInboxParams[1]);

        // facets[0] == admin, facets[1] == user
        facets = _facets;

        shutdownForNitroBlock = type(uint256).max;

        emit RollupCreated(_machineHash);
        require(isInit(), "INITIALIZE_NOT_INIT");
    }

    function postUpgradeInit() external {
        // it is assumed the rollup contract is behind a Proxy controlled by a proxy admin
        // this function can only be called by the proxy admin contract
        address proxyAdmin = ProxyUtil.getProxyAdmin();
        require(msg.sender == proxyAdmin, "NOT_FROM_ADMIN");

        shutdownForNitroBlock = type(uint256).max;
    }

    function createInitialNode(bytes32 _machineHash) private returns (INode) {
        bytes32 state = RollupLib.stateHash(
            RollupLib.ExecutionState(
                0, // total gas used
                _machineHash,
                0, // inbox count
                0, // send count
                0, // log count
                0, // send acc
                0, // log acc
                block.number, // block proposed
                1 // Initialization message already in inbox
            )
        );
        return
            INode(
                nodeFactory.createNode(
                    state,
                    0, // challenge hash (not challengeable)
                    0, // confirm data
                    0, // prev node
                    block.number // deadline block (not challengeable)
                )
            );
    }

    /**
     * This contract uses a dispatch pattern from EIP-2535: Diamonds
     * together with Open Zeppelin's proxy
     */

    function getFacets() external view returns (address, address) {
        return (getAdminFacet(), getUserFacet());
    }

    function getAdminFacet() public view returns (address) {
        return facets[0];
    }

    function getUserFacet() public view returns (address) {
        return facets[1];
    }

    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual override returns (address) {
        require(msg.data.length >= 4, "NO_FUNC_SIG");
        address rollupOwner = owner;
        // if there is an owner and it is the sender, delegate to admin facet
        address target = rollupOwner != address(0) && rollupOwner == msg.sender
            ? getAdminFacet()
            : getUserFacet();
        require(target.isContract(), "TARGET_NOT_CONTRACT");
        return target;
    }
}

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// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "../INode.sol";
import "../../bridge/interfaces/IOutbox.sol";

interface IRollupUser {
    function initialize(address _stakeToken) external;

    function completeChallenge(address winningStaker, address losingStaker) external;

    function returnOldDeposit(address stakerAddress) external;

    function requireUnresolved(uint256 nodeNum) external view;

    function requireUnresolvedExists() external view;

    function countStakedZombies(INode node) external view returns (uint256);
}

interface IRollupAdmin {
    event OwnerFunctionCalled(uint256 indexed id);

    /**
     * @notice Add a contract authorized to put messages into this rollup's inbox
     * @param _outbox Outbox contract to add
     */
    function setOutbox(IOutbox _outbox) external;

    /**
     * @notice Disable an old outbox from interacting with the bridge
     * @param _outbox Outbox contract to remove
     */
    function removeOldOutbox(address _outbox) external;

    /**
     * @notice Enable or disable an inbox contract
     * @param _inbox Inbox contract to add or remove
     * @param _enabled New status of inbox
     */
    function setInbox(address _inbox, bool _enabled) external;

    /**
     * @notice Pause interaction with the rollup contract
     */
    function pause() external;

    /**
     * @notice Resume interaction with the rollup contract
     */
    function resume() external;

    /**
     * @notice Set the addresses of rollup logic facets called
     * @param newAdminFacet address of logic that owner of rollup calls
     * @param newUserFacet ddress of logic that user of rollup calls
     */
    function setFacets(address newAdminFacet, address newUserFacet) external;

    /**
     * @notice Set the addresses of the validator whitelist
     * @dev It is expected that both arrays are same length, and validator at
     * position i corresponds to the value at position i
     * @param _validator addresses to set in the whitelist
     * @param _val value to set in the whitelist for corresponding address
     */
    function setValidator(address[] memory _validator, bool[] memory _val) external;

    /**
     * @notice Set a new owner address for the rollup
     * @param newOwner address of new rollup owner
     */
    function setOwner(address newOwner) external;

    /**
     * @notice Set minimum assertion period for the rollup
     * @param newPeriod new minimum period for assertions
     */
    function setMinimumAssertionPeriod(uint256 newPeriod) external;

    /**
     * @notice Set number of blocks until a node is considered confirmed
     * @param newConfirmPeriod new number of blocks until a node is confirmed
     */
    function setConfirmPeriodBlocks(uint256 newConfirmPeriod) external;

    /**
     * @notice Set number of extra blocks after a challenge
     * @param newExtraTimeBlocks new number of blocks
     */
    function setExtraChallengeTimeBlocks(uint256 newExtraTimeBlocks) external;

    /**
     * @notice Set speed limit per block
     * @param newAvmGasSpeedLimitPerBlock maximum avmgas to be used per block
     */
    function setAvmGasSpeedLimitPerBlock(uint256 newAvmGasSpeedLimitPerBlock) external;

    /**
     * @notice Set base stake required for an assertion
     * @param newBaseStake maximum avmgas to be used per block
     */
    function setBaseStake(uint256 newBaseStake) external;

    /**
     * @notice Set the token used for stake, where address(0) == eth
     * @dev Before changing the base stake token, you might need to change the
     * implementation of the Rollup User facet!
     * @param newStakeToken address of token used for staking
     */
    function setStakeToken(address newStakeToken) external;

    /**
     * @notice Set max delay for sequencer inbox
     * @param newSequencerInboxMaxDelayBlocks max number of blocks
     * @param newSequencerInboxMaxDelaySeconds max number of seconds
     */
    function setSequencerInboxMaxDelay(
        uint256 newSequencerInboxMaxDelayBlocks,
        uint256 newSequencerInboxMaxDelaySeconds
    ) external;

    /**
     * @notice Set execution bisection degree
     * @param newChallengeExecutionBisectionDegree execution bisection degree
     */
    function setChallengeExecutionBisectionDegree(uint256 newChallengeExecutionBisectionDegree)
        external;

    /**
     * @notice Updates a whitelist address for its consumers
     * @dev setting the newWhitelist to address(0) disables it for consumers
     * @param whitelist old whitelist to be deprecated
     * @param newWhitelist new whitelist to be used
     * @param targets whitelist consumers to be triggered
     */
    function updateWhitelistConsumers(
        address whitelist,
        address newWhitelist,
        address[] memory targets
    ) external;

    /**
     * @notice Updates a whitelist's entries
     * @dev user at position i will be assigned value i
     * @param whitelist whitelist to be updated
     * @param user users to be updated in the whitelist
     * @param val if user is or not allowed in the whitelist
     */
    function setWhitelistEntries(
        address whitelist,
        address[] memory user,
        bool[] memory val
    ) external;

    /**
     * @notice Updates whether an address is a sequencer at the sequencer inbox
     * @param newSequencer address to be modified
     * @param isSequencer whether this address should be authorized as a sequencer
     */
    function setIsSequencer(address newSequencer, bool isSequencer) external;

    /**
     * @notice Upgrades the implementation of a beacon controlled by the rollup
     * @param beacon address of beacon to be upgraded
     * @param newImplementation new address of implementation
     */
    function upgradeBeacon(address beacon, address newImplementation) external;

    function forceResolveChallenge(address[] memory stackerA, address[] memory stackerB) external;

    function forceRefundStaker(address[] memory stacker) external;

    function forceCreateNode(
        bytes32 expectedNodeHash,
        bytes32[3][2] calldata assertionBytes32Fields,
        uint256[4][2] calldata assertionIntFields,
        bytes calldata sequencerBatchProof,
        uint256 beforeProposedBlock,
        uint256 beforeInboxMaxCount,
        uint256 prevNode
    ) external;

    function forceConfirmNode(
        uint256 nodeNum,
        bytes32 beforeSendAcc,
        bytes calldata sendsData,
        uint256[] calldata sendLengths,
        uint256 afterSendCount,
        bytes32 afterLogAcc,
        uint256 afterLogCount
    ) external;
}

interface INitroRollupCore {
    function inbox() external view returns (address);

    function owner() external view returns (address);
}

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// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

pragma experimental ABIEncoderV2;

import "./interfaces/IInbox.sol";
import "@arbitrum/nitro-contracts/src/bridge/IBridge.sol" as INitroBridge;
import "@arbitrum/nitro-contracts/src/bridge/IInbox.sol" as INitroInbox;

interface INitroRollup {
    struct GlobalState {
        bytes32[2] bytes32Vals;
        uint64[2] u64Vals;
    }

    enum MachineStatus {
        RUNNING,
        FINISHED,
        ERRORED,
        TOO_FAR
    }

    struct ExecutionState {
        GlobalState globalState;
        MachineStatus machineStatus;
    }
    struct NitroRollupAssertion {
        ExecutionState beforeState;
        ExecutionState afterState;
        uint64 numBlocks;
    }

    function bridge() external view returns (INitroBridge.IBridge);

    function inbox() external view returns (INitroInbox.IInbox);

    function setInbox(IInbox newInbox) external;

    function setOwner(address newOwner) external;

    function paused() external view returns (bool);

    function pause() external;

    function resume() external;

    function latestNodeCreated() external returns (uint64);

    function createNitroMigrationGenesis(NitroRollupAssertion calldata assertion) external;
}

interface IArbOwner {
    function addChainOwner(address newOwner) external;
}

/// @dev lib used since file level consts aren't available in this solc version
library NitroReadyMagicNums {
    uint256 constant ROLLUP_USER = 0xa4b1;
    uint256 constant ROLLUP_ADMIN = 0xa4b2;
    uint256 constant NODE_BEACON = 0xa4b3;
    uint256 constant OUTBOX = 0xa4b4;
    uint256 constant BRIDGE = 0xa4b5;
    uint256 constant DELAYED_INBOX = 0xa4b6;
    uint256 constant SEQ_INBOX = 0xa4b7;
}

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// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "./Context.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor () internal {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

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// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 *
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 *
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     *
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal virtual {
        // solhint-disable-next-line no-inline-assembly
        assembly {
            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())

            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)

            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())

            switch result
            // delegatecall returns 0 on error.
            case 0 { revert(0, returndatasize()) }
            default { return(0, returndatasize()) }
        }
    }

    /**
     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual returns (address);

    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     *
     * This function does not return to its internall call site, it will return directly to the external caller.
     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback () external payable virtual {
        _fallback();
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive () external payable virtual {
        _fallback();
    }

    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     *
     * If overriden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {
    }
}

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// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

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// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

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// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "./Rollup.sol";
import "./facets/IRollupFacets.sol";

import "../bridge/interfaces/IBridge.sol";
import "../bridge/interfaces/IMessageProvider.sol";
import "./INode.sol";
import "../libraries/Cloneable.sol";

contract RollupEventBridge is IMessageProvider, Cloneable {
    uint8 internal constant INITIALIZATION_MSG_TYPE = 11;
    uint8 internal constant ROLLUP_PROTOCOL_EVENT_TYPE = 8;

    uint8 internal constant CREATE_NODE_EVENT = 0;
    uint8 internal constant CONFIRM_NODE_EVENT = 1;
    uint8 internal constant REJECT_NODE_EVENT = 2;
    uint8 internal constant STAKE_CREATED_EVENT = 3;

    IBridge bridge;
    address rollup;

    modifier onlyRollup() {
        require(msg.sender == rollup, "ONLY_ROLLUP");
        _;
    }

    function initialize(address _bridge, address _rollup) external {
        require(rollup == address(0), "ALREADY_INIT");
        bridge = IBridge(_bridge);
        rollup = _rollup;
    }

    function rollupInitialized(
        uint256 confirmPeriodBlocks,
        uint256 avmGasSpeedLimitPerBlock,
        address owner,
        bytes calldata extraConfig
    ) external onlyRollup {
        bytes memory initMsg = abi.encodePacked(
            keccak256("ChallengePeriodEthBlocks"),
            confirmPeriodBlocks,
            keccak256("SpeedLimitPerSecond"),
            avmGasSpeedLimitPerBlock / 100, // convert avm gas to arbgas
            keccak256("ChainOwner"),
            uint256(uint160(bytes20(owner))),
            extraConfig
        );
        uint256 num = bridge.deliverMessageToInbox(
            INITIALIZATION_MSG_TYPE,
            address(0),
            keccak256(initMsg)
        );
        emit InboxMessageDelivered(num, initMsg);
    }

    function nodeCreated(
        uint256 nodeNum,
        uint256 prev,
        uint256 deadline,
        address asserter
    ) external onlyRollup {
        deliverToBridge(
            abi.encodePacked(
                CREATE_NODE_EVENT,
                nodeNum,
                prev,
                block.number,
                deadline,
                uint256(uint160(bytes20(asserter)))
            )
        );
    }

    function nodeConfirmed(uint256 nodeNum) external onlyRollup {
        deliverToBridge(abi.encodePacked(CONFIRM_NODE_EVENT, nodeNum));
    }

    function nodeRejected(uint256 nodeNum) external onlyRollup {
        deliverToBridge(abi.encodePacked(REJECT_NODE_EVENT, nodeNum));
    }

    function stakeCreated(address staker, uint256 nodeNum) external onlyRollup {
        deliverToBridge(
            abi.encodePacked(
                STAKE_CREATED_EVENT,
                uint256(uint160(bytes20(staker))),
                nodeNum,
                block.number
            )
        );
    }

    function deliverToBridge(bytes memory message) private {
        emit InboxMessageDelivered(
            bridge.deliverMessageToInbox(
                ROLLUP_PROTOCOL_EVENT_TYPE,
                msg.sender,
                keccak256(message)
            ),
            message
        );
    }
}

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// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "./INode.sol";
import "./IRollupCore.sol";
import "./RollupLib.sol";
import "./INodeFactory.sol";
import "./RollupEventBridge.sol";
import "../bridge/interfaces/ISequencerInbox.sol";

import "@openzeppelin/contracts/math/SafeMath.sol";

contract RollupCore is IRollupCore {
    using SafeMath for uint256;

    // Stakers become Zombies after losing a challenge
    struct Zombie {
        address stakerAddress;
        uint256 latestStakedNode;
    }

    struct Staker {
        uint256 index;
        uint256 latestStakedNode;
        uint256 amountStaked;
        // currentChallenge is 0 if staker is not in a challenge
        address currentChallenge;
        bool isStaked;
    }

    uint256 private _latestConfirmed;
    uint256 private _firstUnresolvedNode;
    uint256 private _latestNodeCreated;
    uint256 private _lastStakeBlock;
    mapping(uint256 => INode) private _nodes;
    mapping(uint256 => bytes32) private _nodeHashes;

    address payable[] private _stakerList;
    mapping(address => Staker) public override _stakerMap;

    Zombie[] private _zombies;

    mapping(address => uint256) private _withdrawableFunds;

    /**
     * @notice Get the address of the Node contract for the given node
     * @param nodeNum Index of the node
     * @return Address of the Node contract
     */
    function getNode(uint256 nodeNum) public view override returns (INode) {
        return _nodes[nodeNum];
    }

    /**
     * @notice Get the address of the staker at the given index
     * @param stakerNum Index of the staker
     * @return Address of the staker
     */
    function getStakerAddress(uint256 stakerNum) public view override returns (address) {
        return _stakerList[stakerNum];
    }

    /**
     * @notice Check whether the given staker is staked
     * @param staker Staker address to check
     * @return True or False for whether the staker was staked
     */
    function isStaked(address staker) public view override returns (bool) {
        return _stakerMap[staker].isStaked;
    }

    /**
     * @notice Get the latest staked node of the given staker
     * @param staker Staker address to lookup
     * @return Latest node staked of the staker
     */
    function latestStakedNode(address staker) public view override returns (uint256) {
        return _stakerMap[staker].latestStakedNode;
    }

    /**
     * @notice Get the current challenge of the given staker
     * @param staker Staker address to lookup
     * @return Current challenge of the staker
     */
    function currentChallenge(address staker) public view override returns (address) {
        return _stakerMap[staker].currentChallenge;
    }

    /**
     * @notice Get the amount staked of the given staker
     * @param staker Staker address to lookup
     * @return Amount staked of the staker
     */
    function amountStaked(address staker) public view override returns (uint256) {
        return _stakerMap[staker].amountStaked;
    }

    /**
     * @notice Get the original staker address of the zombie at the given index
     * @param zombieNum Index of the zombie to lookup
     * @return Original staker address of the zombie
     */
    function zombieAddress(uint256 zombieNum) public view override returns (address) {
        return _zombies[zombieNum].stakerAddress;
    }

    /**
     * @notice Get Latest node that the given zombie at the given index is staked on
     * @param zombieNum Index of the zombie to lookup
     * @return Latest node that the given zombie is staked on
     */
    function zombieLatestStakedNode(uint256 zombieNum) public view override returns (uint256) {
        return _zombies[zombieNum].latestStakedNode;
    }

    /// @return Current number of un-removed zombies
    function zombieCount() public view override returns (uint256) {
        return _zombies.length;
    }

    function isZombie(address staker) public view override returns (bool) {
        for (uint256 i = 0; i < _zombies.length; i++) {
            if (staker == _zombies[i].stakerAddress) {
                return true;
            }
        }
        return false;
    }

    /**
     * @notice Get the amount of funds withdrawable by the given address
     * @param owner Address to check the funds of
     * @return Amount of funds withdrawable by owner
     */
    function withdrawableFunds(address owner) external view override returns (uint256) {
        return _withdrawableFunds[owner];
    }

    /**
     * @return Index of the first unresolved node
     * @dev If all nodes have been resolved, this will be latestNodeCreated + 1
     */
    function firstUnresolvedNode() public view override returns (uint256) {
        return _firstUnresolvedNode;
    }

    /// @return Index of the latest confirmed node
    function latestConfirmed() public view override returns (uint256) {
        return _latestConfirmed;
    }

    /// @return Index of the latest rollup node created
    function latestNodeCreated() public view override returns (uint256) {
        return _latestNodeCreated;
    }

    /// @return Ethereum block that the most recent stake was created
    function lastStakeBlock() external view override returns (uint256) {
        return _lastStakeBlock;
    }

    /// @return Number of active stakers currently staked
    function stakerCount() public view override returns (uint256) {
        return _stakerList.length;
    }

    /**
     * @notice Initialize the core with an initial node
     * @param initialNode Initial node to start the chain with
     */
    function initializeCore(INode initialNode) internal {
        _nodes[0] = initialNode;
        _firstUnresolvedNode = 1;
    }

    /**
     * @notice React to a new node being created by storing it an incrementing the latest node counter
     * @param node Node that was newly created
     * @param nodeHash The hash of said node
     */
    function nodeCreated(INode node, bytes32 nodeHash) internal {
        _latestNodeCreated++;
        _nodes[_latestNodeCreated] = node;
        _nodeHashes[_latestNodeCreated] = nodeHash;
    }

    /// @return Node hash as of this node number
    function getNodeHash(uint256 index) public view override returns (bytes32) {
        return _nodeHashes[index];
    }

    /// @notice Reject the next unresolved node
    function _rejectNextNode() internal {
        destroyNode(_firstUnresolvedNode);
        _firstUnresolvedNode++;
    }

    /// @notice Confirm the next unresolved node
    function confirmNextNode(
        bytes32 beforeSendAcc,
        bytes calldata sendsData,
        uint256[] calldata sendLengths,
        uint256 afterSendCount,
        bytes32 afterLogAcc,
        uint256 afterLogCount,
        IOutbox outbox,
        RollupEventBridge rollupEventBridge
    ) internal {
        confirmNode(
            _firstUnresolvedNode,
            beforeSendAcc,
            sendsData,
            sendLengths,
            afterSendCount,
            afterLogAcc,
            afterLogCount,
            outbox,
            rollupEventBridge
        );
    }

    function confirmNode(
        uint256 nodeNum,
        bytes32 beforeSendAcc,
        bytes calldata sendsData,
        uint256[] calldata sendLengths,
        uint256 afterSendCount,
        bytes32 afterLogAcc,
        uint256 afterLogCount,
        IOutbox outbox,
        RollupEventBridge rollupEventBridge
    ) internal {
        bytes32 afterSendAcc = RollupLib.feedAccumulator(sendsData, sendLengths, beforeSendAcc);

        INode node = getNode(nodeNum);
        // Authenticate data against node's confirm data pre-image
        require(
            node.confirmData() ==
                RollupLib.confirmHash(
                    beforeSendAcc,
                    afterSendAcc,
                    afterLogAcc,
                    afterSendCount,
                    afterLogCount
                ),
            "CONFIRM_DATA"
        );

        // trusted external call to outbox
        outbox.processOutgoingMessages(sendsData, sendLengths);

        destroyNode(_latestConfirmed);
        _latestConfirmed = nodeNum;
        _firstUnresolvedNode = nodeNum + 1;

        rollupEventBridge.nodeConfirmed(nodeNum);
        emit NodeConfirmed(nodeNum, afterSendAcc, afterSendCount, afterLogAcc, afterLogCount);
    }

    /**
     * @notice Create a new stake at latest confirmed node
     * @param stakerAddress Address of the new staker
     * @param depositAmount Stake amount of the new staker
     */
    function createNewStake(address payable stakerAddress, uint256 depositAmount) internal {
        uint256 stakerIndex = _stakerList.length;
        _stakerList.push(stakerAddress);
        _stakerMap[stakerAddress] = Staker(
            stakerIndex,
            _latestConfirmed,
            depositAmount,
            address(0), // new staker is not in challenge
            true
        );
        _lastStakeBlock = block.number;
        emit UserStakeUpdated(stakerAddress, 0, depositAmount);
    }

    /**
     * @notice Check to see whether the two stakers are in the same challenge
     * @param stakerAddress1 Address of the first staker
     * @param stakerAddress2 Address of the second staker
     * @return Address of the challenge that the two stakers are in
     */
    function inChallenge(address stakerAddress1, address stakerAddress2)
        internal
        view
        returns (address)
    {
        Staker storage staker1 = _stakerMap[stakerAddress1];
        Staker storage staker2 = _stakerMap[stakerAddress2];
        address challenge = staker1.currentChallenge;
        require(challenge != address(0), "NO_CHAL");
        require(challenge == staker2.currentChallenge, "DIFF_IN_CHAL");
        return challenge;
    }

    /**
     * @notice Make the given staker as not being in a challenge
     * @param stakerAddress Address of the staker to remove from a challenge
     */
    function clearChallenge(address stakerAddress) internal {
        Staker storage staker = _stakerMap[stakerAddress];
        staker.currentChallenge = address(0);
    }

    /**
     * @notice Mark both the given stakers as engaged in the challenge
     * @param staker1 Address of the first staker
     * @param staker2 Address of the second staker
     * @param challenge Address of the challenge both stakers are now in
     */
    function challengeStarted(
        address staker1,
        address staker2,
        address challenge
    ) internal {
        _stakerMap[staker1].currentChallenge = challenge;
        _stakerMap[staker2].currentChallenge = challenge;
    }

    /**
     * @notice Add to the stake of the given staker by the given amount
     * @param stakerAddress Address of the staker to increase the stake of
     * @param amountAdded Amount of stake to add to the staker
     */
    function increaseStakeBy(address stakerAddress, uint256 amountAdded) internal {
        Staker storage staker = _stakerMap[stakerAddress];
        uint256 initialStaked = staker.amountStaked;
        uint256 finalStaked = initialStaked.add(amountAdded);
        staker.amountStaked = finalStaked;
        emit UserStakeUpdated(stakerAddress, initialStaked, finalStaked);
    }

    /**
     * @notice Reduce the stake of the given staker to the given target
     * @param stakerAddress Address of the staker to reduce the stake of
     * @param target Amount of stake to leave with the staker
     * @return Amount of value released from the stake
     */
    function reduceStakeTo(address stakerAddress, uint256 target) internal returns (uint256) {
        Staker storage staker = _stakerMap[stakerAddress];
        uint256 current = staker.amountStaked;
        require(target <= current, "TOO_LITTLE_STAKE");
        uint256 amountWithdrawn = current.sub(target);
        staker.amountStaked = target;
        increaseWithdrawableFunds(stakerAddress, amountWithdrawn);
        emit UserStakeUpdated(stakerAddress, current, target);
        return amountWithdrawn;
    }

    /**
     * @notice Remove the given staker and turn them into a zombie
     * @param stakerAddress Address of the staker to remove
     */
    function turnIntoZombie(address stakerAddress) internal {
        Staker storage staker = _stakerMap[stakerAddress];
        _zombies.push(Zombie(stakerAddress, staker.latestStakedNode));
        deleteStaker(stakerAddress);
    }

    /**
     * @notice Update the latest staked node of the zombie at the given index
     * @param zombieNum Index of the zombie to move
     * @param latest New latest node the zombie is staked on
     */
    function zombieUpdateLatestStakedNode(uint256 zombieNum, uint256 latest) internal {
        _zombies[zombieNum].latestStakedNode = latest;
    }

    /**
     * @notice Remove the zombie at the given index
     * @param zombieNum Index of the zombie to remove
     */
    function removeZombie(uint256 zombieNum) internal {
        _zombies[zombieNum] = _zombies[_zombies.length - 1];
        _zombies.pop();
    }

    /**
     * @notice Remove the given staker and return their stake
     * @param stakerAddress Address of the staker withdrawing their stake
     */
    function withdrawStaker(address stakerAddress) internal {
        Staker storage staker = _stakerMap[stakerAddress];
        uint256 initialStaked = staker.amountStaked;
        increaseWithdrawableFunds(stakerAddress, initialStaked);
        deleteStaker(stakerAddress);
        emit UserStakeUpdated(stakerAddress, initialStaked, 0);
    }

    /**
     * @notice Advance the given staker to the given node
     * @param stakerAddress Address of the staker adding their stake
     * @param nodeNum Index of the node to stake on
     */
    function stakeOnNode(
        address stakerAddress,
        uint256 nodeNum,
        uint256 confirmPeriodBlocks
    ) internal {
        Staker storage staker = _stakerMap[stakerAddress];
        INode node = _nodes[nodeNum];
        uint256 newStakerCount = node.addStaker(stakerAddress);
        staker.latestStakedNode = nodeNum;
        if (newStakerCount == 1) {
            INode parent = _nodes[node.prev()];
            parent.newChildConfirmDeadline(block.number.add(confirmPeriodBlocks));
        }
    }

    /**
     * @notice Clear the withdrawable funds for the given address
     * @param owner Address of the account to remove funds from
     * @return Amount of funds removed from account
     */
    function withdrawFunds(address owner) internal returns (uint256) {
        uint256 amount = _withdrawableFunds[owner];
        _withdrawableFunds[owner] = 0;
        emit UserWithdrawableFundsUpdated(owner, amount, 0);
        return amount;
    }

    /**
     * @notice Increase the withdrawable funds for the given address
     * @param owner Address of the account to add withdrawable funds to
     */
    function increaseWithdrawableFunds(address owner, uint256 amount) internal {
        uint256 initialWithdrawable = _withdrawableFunds[owner];
        uint256 finalWithdrawable = initialWithdrawable.add(amount);
        _withdrawableFunds[owner] = finalWithdrawable;
        emit UserWithdrawableFundsUpdated(owner, initialWithdrawable, finalWithdrawable);
    }

    /**
     * @notice Remove the given staker
     * @param stakerAddress Address of the staker to remove
     */
    function deleteStaker(address stakerAddress) private {
        Staker storage staker = _stakerMap[stakerAddress];
        uint256 stakerIndex = staker.index;
        _stakerList[stakerIndex] = _stakerList[_stakerList.length - 1];
        _stakerMap[_stakerList[stakerIndex]].index = stakerIndex;
        _stakerList.pop();
        delete _stakerMap[stakerAddress];
    }

    /**
     * @notice Destroy the given node and clear out its address
     * @param nodeNum Index of the node to remove
     */
    function destroyNode(uint256 nodeNum) internal {
        _nodes[nodeNum].destroy();
        _nodes[nodeNum] = INode(0);
    }

    function nodeDeadline(
        uint256 avmGasSpeedLimitPerBlock,
        uint256 gasUsed,
        uint256 confirmPeriodBlocks,
        INode prevNode
    ) internal view returns (uint256 deadlineBlock) {
        // Set deadline rounding up to the nearest block
        uint256 checkTime = gasUsed.add(avmGasSpeedLimitPerBlock.sub(1)).div(
            avmGasSpeedLimitPerBlock
        );

        deadlineBlock = max(block.number.add(confirmPeriodBlocks), prevNode.deadlineBlock()).add(
            checkTime
        );

        uint256 olderSibling = prevNode.latestChildNumber();
        if (olderSibling != 0) {
            deadlineBlock = max(deadlineBlock, getNode(olderSibling).deadlineBlock());
        }
        return deadlineBlock;
    }

    function max(uint256 a, uint256 b) internal pure returns (uint256) {
        return a > b ? a : b;
    }

    struct StakeOnNewNodeFrame {
        uint256 currentInboxSize;
        INode node;
        bytes32 executionHash;
        INode prevNode;
        bytes32 lastHash;
        bool hasSibling;
        uint256 deadlineBlock;
        uint256 gasUsed;
        uint256 sequencerBatchEnd;
        bytes32 sequencerBatchAcc;
    }

    struct CreateNodeDataFrame {
        uint256 prevNode;
        uint256 confirmPeriodBlocks;
        uint256 avmGasSpeedLimitPerBlock;
        ISequencerInbox sequencerInbox;
        RollupEventBridge rollupEventBridge;
        INodeFactory nodeFactory;
    }

    uint8 internal constant MAX_SEND_COUNT = 100;

    function createNewNode(
        RollupLib.Assertion memory assertion,
        bytes32[3][2] calldata assertionBytes32Fields,
        uint256[4][2] calldata assertionIntFields,
        bytes calldata sequencerBatchProof,
        CreateNodeDataFrame memory inputDataFrame,
        bytes32 expectedNodeHash
    ) internal returns (bytes32 newNodeHash) {
        StakeOnNewNodeFrame memory memoryFrame;
        {
            // validate data
            memoryFrame.gasUsed = RollupLib.assertionGasUsed(assertion);
            memoryFrame.prevNode = getNode(inputDataFrame.prevNode);
            memoryFrame.currentInboxSize = inputDataFrame.sequencerInbox.messageCount();

            // Make sure the previous state is correct against the node being built on
            require(
                RollupLib.stateHash(assertion.beforeState) == memoryFrame.prevNode.stateHash(),
                "PREV_STATE_HASH"
            );

            // Ensure that the assertion doesn't read past the end of the current inbox
            require(
                assertion.afterState.inboxCount <= memoryFrame.currentInboxSize,
                "INBOX_PAST_END"
            );
            // Insure inbox tip after assertion is included in a sequencer-inbox batch and return inbox acc; this gives replay protection against the state of the inbox
            (memoryFrame.sequencerBatchEnd, memoryFrame.sequencerBatchAcc) = inputDataFrame
                .sequencerInbox
                .proveInboxContainsMessage(sequencerBatchProof, assertion.afterState.inboxCount);
        }

        {
            memoryFrame.executionHash = RollupLib.executionHash(assertion);

            memoryFrame.deadlineBlock = nodeDeadline(
                inputDataFrame.avmGasSpeedLimitPerBlock,
                memoryFrame.gasUsed,
                inputDataFrame.confirmPeriodBlocks,
                memoryFrame.prevNode
            );

            memoryFrame.hasSibling = memoryFrame.prevNode.latestChildNumber() > 0;
            // here we don't use ternacy operator to remain compatible with slither
            if (memoryFrame.hasSibling) {
                memoryFrame.lastHash = getNodeHash(memoryFrame.prevNode.latestChildNumber());
            } else {
                memoryFrame.lastHash = getNodeHash(inputDataFrame.prevNode);
            }

            memoryFrame.node = INode(
                inputDataFrame.nodeFactory.createNode(
                    RollupLib.stateHash(assertion.afterState),
                    RollupLib.challengeRoot(assertion, memoryFrame.executionHash, block.number),
                    RollupLib.confirmHash(assertion),
                    inputDataFrame.prevNode,
                    memoryFrame.deadlineBlock
                )
            );
        }

        {
            uint256 nodeNum = latestNodeCreated() + 1;
            memoryFrame.prevNode.childCreated(nodeNum);

            newNodeHash = RollupLib.nodeHash(
                memoryFrame.hasSibling,
                memoryFrame.lastHash,
                memoryFrame.executionHash,
                memoryFrame.sequencerBatchAcc
            );
            require(newNodeHash == expectedNodeHash, "UNEXPECTED_NODE_HASH");

            nodeCreated(memoryFrame.node, newNodeHash);
            inputDataFrame.rollupEventBridge.nodeCreated(
                nodeNum,
                inputDataFrame.prevNode,
                memoryFrame.deadlineBlock,
                msg.sender
            );
        }

        emit NodeCreated(
            latestNodeCreated(),
            getNodeHash(inputDataFrame.prevNode),
            newNodeHash,
            memoryFrame.executionHash,
            memoryFrame.currentInboxSize,
            memoryFrame.sequencerBatchEnd,
            memoryFrame.sequencerBatchAcc,
            assertionBytes32Fields,
            assertionIntFields
        );

        return newNodeHash;
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "../challenge/ChallengeLib.sol";
import "./INode.sol";

import "@openzeppelin/contracts/math/SafeMath.sol";

library RollupLib {
    using SafeMath for uint256;

    struct Config {
        bytes32 machineHash;
        uint256 confirmPeriodBlocks;
        uint256 extraChallengeTimeBlocks;
        uint256 avmGasSpeedLimitPerBlock;
        uint256 baseStake;
        address stakeToken;
        address owner;
        address sequencer;
        uint256 sequencerDelayBlocks;
        uint256 sequencerDelaySeconds;
        bytes extraConfig;
    }

    struct ExecutionState {
        uint256 gasUsed;
        bytes32 machineHash;
        uint256 inboxCount;
        uint256 sendCount;
        uint256 logCount;
        bytes32 sendAcc;
        bytes32 logAcc;
        uint256 proposedBlock;
        uint256 inboxMaxCount;
    }

    function stateHash(ExecutionState memory execState) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    execState.gasUsed,
                    execState.machineHash,
                    execState.inboxCount,
                    execState.sendCount,
                    execState.logCount,
                    execState.sendAcc,
                    execState.logAcc,
                    execState.proposedBlock,
                    execState.inboxMaxCount
                )
            );
    }

    struct Assertion {
        ExecutionState beforeState;
        ExecutionState afterState;
    }

    function decodeExecutionState(
        bytes32[3] memory bytes32Fields,
        uint256[4] memory intFields,
        uint256 proposedBlock,
        uint256 inboxMaxCount
    ) internal pure returns (ExecutionState memory) {
        return
            ExecutionState(
                intFields[0],
                bytes32Fields[0],
                intFields[1],
                intFields[2],
                intFields[3],
                bytes32Fields[1],
                bytes32Fields[2],
                proposedBlock,
                inboxMaxCount
            );
    }

    function decodeAssertion(
        bytes32[3][2] memory bytes32Fields,
        uint256[4][2] memory intFields,
        uint256 beforeProposedBlock,
        uint256 beforeInboxMaxCount,
        uint256 inboxMaxCount
    ) internal view returns (Assertion memory) {
        return
            Assertion(
                decodeExecutionState(
                    bytes32Fields[0],
                    intFields[0],
                    beforeProposedBlock,
                    beforeInboxMaxCount
                ),
                decodeExecutionState(bytes32Fields[1], intFields[1], block.number, inboxMaxCount)
            );
    }

    function executionStateChallengeHash(ExecutionState memory state)
        internal
        pure
        returns (bytes32)
    {
        return
            ChallengeLib.assertionHash(
                state.gasUsed,
                ChallengeLib.assertionRestHash(
                    state.inboxCount,
                    state.machineHash,
                    state.sendAcc,
                    state.sendCount,
                    state.logAcc,
                    state.logCount
                )
            );
    }

    function executionHash(Assertion memory assertion) internal pure returns (bytes32) {
        return
            ChallengeLib.bisectionChunkHash(
                assertion.beforeState.gasUsed,
                assertion.afterState.gasUsed - assertion.beforeState.gasUsed,
                RollupLib.executionStateChallengeHash(assertion.beforeState),
                RollupLib.executionStateChallengeHash(assertion.afterState)
            );
    }

    function assertionGasUsed(RollupLib.Assertion memory assertion)
        internal
        pure
        returns (uint256)
    {
        return assertion.afterState.gasUsed.sub(assertion.beforeState.gasUsed);
    }

    function challengeRoot(
        Assertion memory assertion,
        bytes32 assertionExecHash,
        uint256 blockProposed
    ) internal pure returns (bytes32) {
        return challengeRootHash(assertionExecHash, blockProposed, assertion.afterState.inboxCount);
    }

    function challengeRootHash(
        bytes32 execution,
        uint256 proposedTime,
        uint256 maxMessageCount
    ) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked(execution, proposedTime, maxMessageCount));
    }

    function confirmHash(Assertion memory assertion) internal pure returns (bytes32) {
        return
            confirmHash(
                assertion.beforeState.sendAcc,
                assertion.afterState.sendAcc,
                assertion.afterState.logAcc,
                assertion.afterState.sendCount,
                assertion.afterState.logCount
            );
    }

    function confirmHash(
        bytes32 beforeSendAcc,
        bytes32 afterSendAcc,
        bytes32 afterLogAcc,
        uint256 afterSendCount,
        uint256 afterLogCount
    ) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    beforeSendAcc,
                    afterSendAcc,
                    afterSendCount,
                    afterLogAcc,
                    afterLogCount
                )
            );
    }

    function feedAccumulator(
        bytes memory messageData,
        uint256[] memory messageLengths,
        bytes32 beforeAcc
    ) internal pure returns (bytes32) {
        uint256 offset = 0;
        uint256 messageCount = messageLengths.length;
        uint256 dataLength = messageData.length;
        bytes32 messageAcc = beforeAcc;
        for (uint256 i = 0; i < messageCount; i++) {
            uint256 messageLength = messageLengths[i];
            require(offset + messageLength <= dataLength, "DATA_OVERRUN");
            bytes32 messageHash;
            assembly {
                messageHash := keccak256(add(messageData, add(offset, 32)), messageLength)
            }
            messageAcc = keccak256(abi.encodePacked(messageAcc, messageHash));
            offset += messageLength;
        }
        require(offset == dataLength, "DATA_LENGTH");
        return messageAcc;
    }

    function nodeHash(
        bool hasSibling,
        bytes32 lastHash,
        bytes32 assertionExecHash,
        bytes32 inboxAcc
    ) internal pure returns (bytes32) {
        uint8 hasSiblingInt = hasSibling ? 1 : 0;
        return keccak256(abi.encodePacked(hasSiblingInt, lastHash, assertionExecHash, inboxAcc));
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface INode {
    function initialize(
        address _rollup,
        bytes32 _stateHash,
        bytes32 _challengeHash,
        bytes32 _confirmData,
        uint256 _prev,
        uint256 _deadlineBlock
    ) external;

    function destroy() external;

    function addStaker(address staker) external returns (uint256);

    function removeStaker(address staker) external;

    function childCreated(uint256) external;

    function newChildConfirmDeadline(uint256 deadline) external;

    function stateHash() external view returns (bytes32);

    function challengeHash() external view returns (bytes32);

    function confirmData() external view returns (bytes32);

    function prev() external view returns (uint256);

    function deadlineBlock() external view returns (uint256);

    function noChildConfirmedBeforeBlock() external view returns (uint256);

    function stakerCount() external view returns (uint256);

    function stakers(address staker) external view returns (bool);

    function firstChildBlock() external view returns (uint256);

    function latestChildNumber() external view returns (uint256);

    function requirePastDeadline() external view;

    function requirePastChildConfirmDeadline() external view;

    function isNitroReady() external pure returns (uint256);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface INodeFactory {
    function createNode(
        bytes32 _stateHash,
        bytes32 _challengeHash,
        bytes32 _confirmData,
        uint256 _prev,
        uint256 _deadlineBlock
    ) external returns (address);

    function beacon() external view returns (address);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "../bridge/interfaces/IBridge.sol";
import "../bridge/interfaces/ISequencerInbox.sol";
import "../arch/IOneStepProof.sol";

interface IChallenge {
    function initializeChallenge(
        IOneStepProof[] calldata _executors,
        address _resultReceiver,
        bytes32 _executionHash,
        uint256 _maxMessageCount,
        address _asserter,
        address _challenger,
        uint256 _asserterTimeLeft,
        uint256 _challengerTimeLeft,
        ISequencerInbox _sequencerBridge,
        IBridge _delayedBridge
    ) external;

    function currentResponderTimeLeft() external view returns (uint256);

    function lastMoveBlock() external view returns (uint256);

    function timeout() external;

    function asserter() external view returns (address);

    function challenger() external view returns (address);

    function clearChallenge() external;
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "../bridge/interfaces/IBridge.sol";
import "../bridge/interfaces/ISequencerInbox.sol";

interface IChallengeFactory {
    function createChallenge(
        address _resultReceiver,
        bytes32 _executionHash,
        uint256 _maxMessageCount,
        address _asserter,
        address _challenger,
        uint256 _asserterTimeLeft,
        uint256 _challengerTimeLeft,
        ISequencerInbox _sequencerBridge,
        IBridge _delayedBridge
    ) external returns (address);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface IBridge {
    event MessageDelivered(
        uint256 indexed messageIndex,
        bytes32 indexed beforeInboxAcc,
        address inbox,
        uint8 kind,
        address sender,
        bytes32 messageDataHash
    );

    event BridgeCallTriggered(
        address indexed outbox,
        address indexed destAddr,
        uint256 amount,
        bytes data
    );

    event InboxToggle(address indexed inbox, bool enabled);

    event OutboxToggle(address indexed outbox, bool enabled);

    function deliverMessageToInbox(
        uint8 kind,
        address sender,
        bytes32 messageDataHash
    ) external payable returns (uint256);

    function executeCall(
        address destAddr,
        uint256 amount,
        bytes calldata data
    ) external returns (bool success, bytes memory returnData);

    // These are only callable by the admin
    function setInbox(address inbox, bool enabled) external;

    function setOutbox(address inbox, bool enabled) external;

    // View functions

    function activeOutbox() external view returns (address);

    function allowedInboxes(address inbox) external view returns (bool);

    function allowedOutboxes(address outbox) external view returns (bool);

    function inboxAccs(uint256 index) external view returns (bytes32);

    function messageCount() external view returns (uint256);

    function isNitroReady() external view returns (uint256);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "./IBridge.sol";

interface IOutbox {
    event OutboxEntryCreated(
        uint256 indexed batchNum,
        uint256 outboxEntryIndex,
        bytes32 outputRoot,
        uint256 numInBatch
    );
    event OutBoxTransactionExecuted(
        address indexed destAddr,
        address indexed l2Sender,
        uint256 indexed outboxEntryIndex,
        uint256 transactionIndex
    );

    function l2ToL1Sender() external view returns (address);

    function l2ToL1Block() external view returns (uint256);

    function l2ToL1EthBlock() external view returns (uint256);

    function l2ToL1Timestamp() external view returns (uint256);

    function l2ToL1BatchNum() external view returns (uint256);

    function l2ToL1OutputId() external view returns (bytes32);

    function processOutgoingMessages(bytes calldata sendsData, uint256[] calldata sendLengths)
        external;

    function outboxEntryExists(uint256 batchNum) external view returns (bool);

    function setBridge(IBridge newBridge) external;

    function isNitroReady() external pure returns (uint256);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

library Messages {
    function messageHash(
        uint8 kind,
        address sender,
        uint256 blockNumber,
        uint256 timestamp,
        uint256 inboxSeqNum,
        uint256 gasPriceL1,
        bytes32 messageDataHash
    ) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    kind,
                    sender,
                    blockNumber,
                    timestamp,
                    inboxSeqNum,
                    gasPriceL1,
                    messageDataHash
                )
            );
    }

    function addMessageToInbox(bytes32 inbox, bytes32 message) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked(inbox, message));
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

library ProxyUtil {
    function getProxyAdmin() internal view returns (address admin) {
        // https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v3.4.0/contracts/proxy/TransparentUpgradeableProxy.sol#L48
        // Storage slot with the admin of the proxy contract.
        // This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
        bytes32 slot = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        assembly {
            admin := sload(slot)
        }
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2020, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "./ICloneable.sol";

contract Cloneable is ICloneable {
    string private constant NOT_CLONE = "NOT_CLONE";

    bool private isMasterCopy;

    constructor() public {
        isMasterCopy = true;
    }

    function isMaster() external view override returns (bool) {
        return isMasterCopy;
    }

    function safeSelfDestruct(address payable dest) internal {
        require(!isMasterCopy, NOT_CLONE);
        selfdestruct(dest);
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface IMessageProvider {
    event InboxMessageDelivered(uint256 indexed messageNum, bytes data);

    event InboxMessageDeliveredFromOrigin(uint256 indexed messageNum);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "./INode.sol";

interface IRollupCore {
    function _stakerMap(address stakerAddress)
        external
        view
        returns (
            uint256,
            uint256,
            uint256,
            address,
            bool
        );

    event RollupCreated(bytes32 machineHash);

    event NodeCreated(
        uint256 indexed nodeNum,
        bytes32 indexed parentNodeHash,
        bytes32 nodeHash,
        bytes32 executionHash,
        uint256 inboxMaxCount,
        uint256 afterInboxBatchEndCount,
        bytes32 afterInboxBatchAcc,
        bytes32[3][2] assertionBytes32Fields,
        uint256[4][2] assertionIntFields
    );

    event NodeConfirmed(
        uint256 indexed nodeNum,
        bytes32 afterSendAcc,
        uint256 afterSendCount,
        bytes32 afterLogAcc,
        uint256 afterLogCount
    );

    event NodeRejected(uint256 indexed nodeNum);

    event RollupChallengeStarted(
        address indexed challengeContract,
        address asserter,
        address challenger,
        uint256 challengedNode
    );

    event UserStakeUpdated(address indexed user, uint256 initialBalance, uint256 finalBalance);

    event UserWithdrawableFundsUpdated(
        address indexed user,
        uint256 initialBalance,
        uint256 finalBalance
    );

    function getNode(uint256 nodeNum) external view returns (INode);

    /**
     * @notice Get the address of the staker at the given index
     * @param stakerNum Index of the staker
     * @return Address of the staker
     */
    function getStakerAddress(uint256 stakerNum) external view returns (address);

    /**
     * @notice Check whether the given staker is staked
     * @param staker Staker address to check
     * @return True or False for whether the staker was staked
     */
    function isStaked(address staker) external view returns (bool);

    /**
     * @notice Get the latest staked node of the given staker
     * @param staker Staker address to lookup
     * @return Latest node staked of the staker
     */
    function latestStakedNode(address staker) external view returns (uint256);

    /**
     * @notice Get the current challenge of the given staker
     * @param staker Staker address to lookup
     * @return Current challenge of the staker
     */
    function currentChallenge(address staker) external view returns (address);

    /**
     * @notice Get the amount staked of the given staker
     * @param staker Staker address to lookup
     * @return Amount staked of the staker
     */
    function amountStaked(address staker) external view returns (uint256);

    /**
     * @notice Get the original staker address of the zombie at the given index
     * @param zombieNum Index of the zombie to lookup
     * @return Original staker address of the zombie
     */
    function zombieAddress(uint256 zombieNum) external view returns (address);

    /**
     * @notice Get Latest node that the given zombie at the given index is staked on
     * @param zombieNum Index of the zombie to lookup
     * @return Latest node that the given zombie is staked on
     */
    function zombieLatestStakedNode(uint256 zombieNum) external view returns (uint256);

    /// @return Current number of un-removed zombies
    function zombieCount() external view returns (uint256);

    function isZombie(address staker) external view returns (bool);

    /**
     * @notice Get the amount of funds withdrawable by the given address
     * @param owner Address to check the funds of
     * @return Amount of funds withdrawable by owner
     */
    function withdrawableFunds(address owner) external view returns (uint256);

    /**
     * @return Index of the first unresolved node
     * @dev If all nodes have been resolved, this will be latestNodeCreated + 1
     */
    function firstUnresolvedNode() external view returns (uint256);

    /// @return Index of the latest confirmed node
    function latestConfirmed() external view returns (uint256);

    /// @return Index of the latest rollup node created
    function latestNodeCreated() external view returns (uint256);

    /// @return Ethereum block that the most recent stake was created
    function lastStakeBlock() external view returns (uint256);

    /// @return Number of active stakers currently staked
    function stakerCount() external view returns (uint256);

    /// @return Node hash as of this node number
    function getNodeHash(uint256 index) external view returns (bytes32);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface ISequencerInbox {
    event SequencerBatchDelivered(
        uint256 indexed firstMessageNum,
        bytes32 indexed beforeAcc,
        uint256 newMessageCount,
        bytes32 afterAcc,
        bytes transactions,
        uint256[] lengths,
        uint256[] sectionsMetadata,
        uint256 seqBatchIndex,
        address sequencer
    );

    event SequencerBatchDeliveredFromOrigin(
        uint256 indexed firstMessageNum,
        bytes32 indexed beforeAcc,
        uint256 newMessageCount,
        bytes32 afterAcc,
        uint256 seqBatchIndex
    );

    event DelayedInboxForced(
        uint256 indexed firstMessageNum,
        bytes32 indexed beforeAcc,
        uint256 newMessageCount,
        uint256 totalDelayedMessagesRead,
        bytes32[2] afterAccAndDelayed,
        uint256 seqBatchIndex
    );

    /// @notice DEPRECATED - look at IsSequencerUpdated for new updates
    // event SequencerAddressUpdated(address newAddress);

    event IsSequencerUpdated(address addr, bool isSequencer);
    event MaxDelayUpdated(uint256 newMaxDelayBlocks, uint256 newMaxDelaySeconds);
    event ShutdownForNitroSet(bool shutdown);

    /// @notice DEPRECATED - look at MaxDelayUpdated for new updates
    // event MaxDelayBlocksUpdated(uint256 newValue);
    /// @notice DEPRECATED - look at MaxDelayUpdated for new updates
    // event MaxDelaySecondsUpdated(uint256 newValue);

    function setMaxDelay(uint256 newMaxDelayBlocks, uint256 newMaxDelaySeconds) external;

    function setIsSequencer(address addr, bool isSequencer) external;

    function messageCount() external view returns (uint256);

    function maxDelayBlocks() external view returns (uint256);

    function maxDelaySeconds() external view returns (uint256);

    function inboxAccs(uint256 index) external view returns (bytes32);

    function getInboxAccsLength() external view returns (uint256);

    function proveInboxContainsMessage(bytes calldata proof, uint256 inboxCount)
        external
        view
        returns (uint256, bytes32);

    /// @notice DEPRECATED - use isSequencer instead
    function sequencer() external view returns (address);

    function isSequencer(address seq) external view returns (bool);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

import "../libraries/MerkleLib.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";

library ChallengeLib {
    using SafeMath for uint256;

    function firstSegmentSize(uint256 totalCount, uint256 bisectionCount)
        internal
        pure
        returns (uint256)
    {
        return totalCount / bisectionCount + (totalCount % bisectionCount);
    }

    function otherSegmentSize(uint256 totalCount, uint256 bisectionCount)
        internal
        pure
        returns (uint256)
    {
        return totalCount / bisectionCount;
    }

    function bisectionChunkHash(
        uint256 _segmentStart,
        uint256 _segmentLength,
        bytes32 _startHash,
        bytes32 _endHash
    ) internal pure returns (bytes32) {
        return keccak256(abi.encodePacked(_segmentStart, _segmentLength, _startHash, _endHash));
    }

    function assertionHash(uint256 _avmGasUsed, bytes32 _restHash) internal pure returns (bytes32) {
        // Note: make sure this doesn't return Challenge.UNREACHABLE_ASSERTION (currently 0)
        return keccak256(abi.encodePacked(_avmGasUsed, _restHash));
    }

    function assertionRestHash(
        uint256 _totalMessagesRead,
        bytes32 _machineState,
        bytes32 _sendAcc,
        uint256 _sendCount,
        bytes32 _logAcc,
        uint256 _logCount
    ) internal pure returns (bytes32) {
        return
            keccak256(
                abi.encodePacked(
                    _totalMessagesRead,
                    _machineState,
                    _sendAcc,
                    _sendCount,
                    _logAcc,
                    _logCount
                )
            );
    }

    function updatedBisectionRoot(
        bytes32[] memory _chainHashes,
        uint256 _challengedSegmentStart,
        uint256 _challengedSegmentLength
    ) internal pure returns (bytes32) {
        uint256 bisectionCount = _chainHashes.length - 1;
        bytes32[] memory hashes = new bytes32[](bisectionCount);
        uint256 chunkSize = ChallengeLib.firstSegmentSize(_challengedSegmentLength, bisectionCount);
        uint256 segmentStart = _challengedSegmentStart;
        hashes[0] = ChallengeLib.bisectionChunkHash(
            segmentStart,
            chunkSize,
            _chainHashes[0],
            _chainHashes[1]
        );
        segmentStart = segmentStart.add(chunkSize);
        chunkSize = ChallengeLib.otherSegmentSize(_challengedSegmentLength, bisectionCount);
        for (uint256 i = 1; i < bisectionCount; i++) {
            hashes[i] = ChallengeLib.bisectionChunkHash(
                segmentStart,
                chunkSize,
                _chainHashes[i],
                _chainHashes[i + 1]
            );
            segmentStart = segmentStart.add(chunkSize);
        }
        return MerkleLib.generateRoot(hashes);
    }

    function verifySegmentProof(
        bytes32 challengeState,
        bytes32 item,
        bytes32[] calldata _merkleNodes,
        uint256 _merkleRoute
    ) internal pure returns (bool) {
        return challengeState == MerkleLib.calculateRoot(_merkleNodes, _merkleRoute, item);
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019-2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

pragma solidity ^0.6.11;

library MerkleLib {
    function generateRoot(bytes32[] memory _hashes) internal pure returns (bytes32) {
        bytes32[] memory prevLayer = _hashes;
        while (prevLayer.length > 1) {
            bytes32[] memory nextLayer = new bytes32[]((prevLayer.length + 1) / 2);
            for (uint256 i = 0; i < nextLayer.length; i++) {
                if (2 * i + 1 < prevLayer.length) {
                    nextLayer[i] = keccak256(
                        abi.encodePacked(prevLayer[2 * i], prevLayer[2 * i + 1])
                    );
                } else {
                    nextLayer[i] = prevLayer[2 * i];
                }
            }
            prevLayer = nextLayer;
        }
        return prevLayer[0];
    }

    function calculateRoot(
        bytes32[] memory nodes,
        uint256 route,
        bytes32 item
    ) internal pure returns (bytes32) {
        uint256 proofItems = nodes.length;
        require(proofItems <= 256);
        bytes32 h = item;
        for (uint256 i = 0; i < proofItems; i++) {
            if (route % 2 == 0) {
                h = keccak256(abi.encodePacked(nodes[i], h));
            } else {
                h = keccak256(abi.encodePacked(h, nodes[i]));
            }
            route /= 2;
        }
        return h;
    }
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2019, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface ICloneable {
    function isMaster() external view returns (bool);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2020, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "../bridge/interfaces/IBridge.sol";
import "../bridge/interfaces/ISequencerInbox.sol";

interface IOneStepProof {
    // Bridges is sequencer bridge then delayed bridge
    function executeStep(
        address[2] calldata bridges,
        uint256 initialMessagesRead,
        bytes32[2] calldata accs,
        bytes calldata proof,
        bytes calldata bproof
    )
        external
        view
        returns (
            uint64 gas,
            uint256 afterMessagesRead,
            bytes32[4] memory fields
        );

    function executeStepDebug(
        address[2] calldata bridges,
        uint256 initialMessagesRead,
        bytes32[2] calldata accs,
        bytes calldata proof,
        bytes calldata bproof
    ) external view returns (string memory startMachine, string memory afterMachine);
}

<i class='far fa-question-circle text-muted ms-2' data-bs-trigger='hover' data-bs-toggle='tooltip' data-bs-html='true' data-bs-title='Click on the check box to select individual contract to compare. Only 1 contract can be selected from each side.'></i>

// SPDX-License-Identifier: Apache-2.0

/*
 * Copyright 2021, Offchain Labs, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "./IBridge.sol";
import "./IMessageProvider.sol";

interface IInbox is IMessageProvider {
    function sendL2Message(bytes calldata messageData) external returns (uint256);

    function sendUnsignedTransaction(
        uint256 maxGas,
        uint256 gasPriceBid,
        uint256 nonce,
        address destAddr,
        uint256 amount,
        bytes calldata data
    ) external returns (uint256);

    function sendContractTransaction(
        uint256 maxGas,
        uint256 gasPriceBid,
        address destAddr,
        uint256 amount,
        bytes calldata data
    ) external returns (uint256);

    function sendL1FundedUnsignedTransaction(
        uint256 maxGas,
        uint256 gasPriceBid,
        uint256 nonce,
        address destAddr,
        bytes calldata data
    ) external payable returns (uint256);

    function sendL1FundedContractTransaction(
        uint256 maxGas,
        uint256 gasPriceBid,
        address destAddr,
        bytes calldata data
    ) external payable returns (uint256);

    function createRetryableTicket(
        address destAddr,
        uint256 arbTxCallValue,
        uint256 maxSubmissionCost,
        address submissionRefundAddress,
        address valueRefundAddress,
        uint256 maxGas,
        uint256 gasPriceBid,
        bytes calldata data
    ) external payable returns (uint256);

    function unsafeCreateRetryableTicket(
        address destAddr,
        uint256 arbTxCallValue,
        uint256 maxSubmissionCost,
        address submissionRefundAddress,
        address valueRefundAddress,
        uint256 maxGas,
        uint256 gasPriceBid,
        bytes calldata data
    ) external payable returns (uint256);

    function depositEth(uint256 maxSubmissionCost) external payable returns (uint256);

    function bridge() external view returns (IBridge);

    function pauseCreateRetryables() external;

    function unpauseCreateRetryables() external;

    function startRewriteAddress() external;

    function stopRewriteAddress() external;
}

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// Copyright 2021-2022, Offchain Labs, Inc.
// For license information, see https://github.com/nitro/blob/master/LICENSE
// SPDX-License-Identifier: BUSL-1.1

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "./IOwnable.sol";

interface IBridge {
    event MessageDelivered(
        uint256 indexed messageIndex,
        bytes32 indexed beforeInboxAcc,
        address inbox,
        uint8 kind,
        address sender,
        bytes32 messageDataHash,
        uint256 baseFeeL1,
        uint64 timestamp
    );

    event BridgeCallTriggered(
        address indexed outbox,
        address indexed to,
        uint256 value,
        bytes data
    );

    event InboxToggle(address indexed inbox, bool enabled);

    event OutboxToggle(address indexed outbox, bool enabled);

    event SequencerInboxUpdated(address newSequencerInbox);

    function enqueueDelayedMessage(
        uint8 kind,
        address sender,
        bytes32 messageDataHash
    ) external payable returns (uint256);

    function enqueueSequencerMessage(bytes32 dataHash, uint256 afterDelayedMessagesRead)
        external
        returns (
            uint256 seqMessageIndex,
            bytes32 beforeAcc,
            bytes32 delayedAcc,
            bytes32 acc
        );

    function submitBatchSpendingReport(address batchPoster, bytes32 dataHash)
        external
        returns (uint256 msgNum);

    function executeCall(
        address to,
        uint256 value,
        bytes calldata data
    ) external returns (bool success, bytes memory returnData);

    // These are only callable by the admin
    function setDelayedInbox(address inbox, bool enabled) external;

    function setOutbox(address inbox, bool enabled) external;

    function setSequencerInbox(address _sequencerInbox) external;

    // View functions

    function sequencerInbox() external view returns (address);

    function activeOutbox() external view returns (address);

    function allowedDelayedInboxes(address inbox) external view returns (bool);

    function allowedOutboxes(address outbox) external view returns (bool);

    function delayedInboxAccs(uint256 index) external view returns (bytes32);

    function sequencerInboxAccs(uint256 index) external view returns (bytes32);

    function delayedMessageCount() external view returns (uint256);

    function sequencerMessageCount() external view returns (uint256);

    function rollup() external view returns (IOwnable);

    function acceptFundsFromOldBridge() external payable;
}

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// Copyright 2021-2022, Offchain Labs, Inc.
// For license information, see https://github.com/nitro/blob/master/LICENSE
// SPDX-License-Identifier: BUSL-1.1

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

import "./IBridge.sol";
import "./IDelayedMessageProvider.sol";

interface IInbox is IDelayedMessageProvider {
    function sendL2Message(bytes calldata messageData) external returns (uint256);

    function sendUnsignedTransaction(
        uint256 gasLimit,
        uint256 maxFeePerGas,
        uint256 nonce,
        address to,
        uint256 value,
        bytes calldata data
    ) external returns (uint256);

    function sendContractTransaction(
        uint256 gasLimit,
        uint256 maxFeePerGas,
        address to,
        uint256 value,
        bytes calldata data
    ) external returns (uint256);

    function sendL1FundedUnsignedTransaction(
        uint256 gasLimit,
        uint256 maxFeePerGas,
        uint256 nonce,
        address to,
        bytes calldata data
    ) external payable returns (uint256);

    function sendL1FundedContractTransaction(
        uint256 gasLimit,
        uint256 maxFeePerGas,
        address to,
        bytes calldata data
    ) external payable returns (uint256);

    /// @dev Gas limit and maxFeePerGas should not be set to 1 as that is used to trigger the RetryableData error
    function createRetryableTicket(
        address to,
        uint256 arbTxCallValue,
        uint256 maxSubmissionCost,
        address submissionRefundAddress,
        address valueRefundAddress,
        uint256 gasLimit,
        uint256 maxFeePerGas,
        bytes calldata data
    ) external payable returns (uint256);

    /// @dev Gas limit and maxFeePerGas should not be set to 1 as that is used to trigger the RetryableData error
    function unsafeCreateRetryableTicket(
        address to,
        uint256 arbTxCallValue,
        uint256 maxSubmissionCost,
        address submissionRefundAddress,
        address valueRefundAddress,
        uint256 gasLimit,
        uint256 maxFeePerGas,
        bytes calldata data
    ) external payable returns (uint256);

    function depositEth() external payable returns (uint256);

    /// @notice deprecated in favour of depositEth with no parameters
    function depositEth(uint256 maxSubmissionCost) external payable returns (uint256);

    function bridge() external view returns (IBridge);

    function postUpgradeInit(IBridge _bridge) external;
}

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// Copyright 2021-2022, Offchain Labs, Inc.
// For license information, see https://github.com/nitro/blob/master/LICENSE
// SPDX-License-Identifier: BUSL-1.1

// solhint-disable-next-line compiler-version
pragma solidity >=0.4.21 <0.9.0;

interface IOwnable {
    function owner() external view returns (address);
}

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// Copyright 2021-2022, Offchain Labs, Inc.
// For license information, see https://github.com/nitro/blob/master/LICENSE
// SPDX-License-Identifier: BUSL-1.1

// solhint-disable-next-line compiler-version
pragma solidity >=0.6.9 <0.9.0;

interface IDelayedMessageProvider {
    /// @dev event emitted when a inbox message is added to the Bridge's delayed accumulator
    event InboxMessageDelivered(uint256 indexed messageNum, bytes data);

    /// @dev event emitted when a inbox message is added to the Bridge's delayed accumulator
    /// same as InboxMessageDelivered but the batch data is available in tx.input
    event InboxMessageDeliveredFromOrigin(uint256 indexed messageNum);
}

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