HolidayDoge - Smart Contract Audit Report
Audit Summary
HolidayDoge ($HOLD) is a new BEP-20 token on the Binance Smart Chain that is an automatic liquidity providing protocol that pays out static rewards to holders.
We reviewed the HolidayDoge contract at 0xd6263e313896d2868117e370Df0DF871a3fb3D0a on the Binance Smart Chain mainnet.
Audit Findings
Please ensure trust in the team prior to investing as they have substantial control in the ecosystem and currently own 100% of the total supply.
Date: January 13th, 2022.
Contract Overview
Ownership Controls:
- The total supply of the token is set to 1 billion $HOLD [1,000,000,000].
- No minting or burn functions are present; though the circulating supply can be reduced by sending tokens to the 0x..dead address if desired.
- At the time of writing this report, 100% of the total supply belongs to the owner.
- There is a tax fee, liquidity fee, and marketing fee on all transfers where neither the sender nor the recipient is excluded from fees.
- The tokens collected from the tax fee are removed from the circulating supply; This serves as a frictionless fee redistribution which automatically benefits all token holders at the time of each transaction.
- The tokens collected from the liquidity fee during transfers are stored in the contract address balance. Once the threshold number of tokens (determined by the owner) is met, a swap will occur for the purpose of funding Pancakeswap liquidity.
- Liquidity-adds are funded by selling a portion of the tokens collected as fees (after the threshold number of tokens is met), then pairing the received BNB with the token, and adding it as liquidity to the BNB pair.
- The recipient of the newly created LP tokens is the owner. We recommend that the team locks these newly acquired LP tokens.
- The tokens collected from the marketing fee are sent to the team's marketing wallet.
- Although logic for a maximum wallet amount exists in the contract, this value is set to 100% of the total supply and cannot be modified.
- Although the SafeMath library is utilized, the contract is deployed with Solidity v0.8.9 which has built-in overflow checks. SafeMath could be safely removed to reduce contract size and deployment costs.
- Some gas optimizations can be achieved through declaring functions external instead of public, and state variables constant. As this contract is already deployed, this is merely informational.
- Ownership has not been renounced.
- The owner can modify the tax fee, liquidity fee, and marketing fee to any percentages at any time.
- The owner can exclude and include accounts from transfer fees and reward distribution.
- The owner can set and update a maximum transaction amount at any time, which will impose a limit to the number of tokens that can be transferred during any given transaction.
- The owner can enable/disable automatic liquidity adds at any time.
- The owner can update the threshold number of tokens that triggers an automatic liquidity add to any value at any time.
- The owner can update the team's Marketing wallet to any address at any time.
Resolved Issues
HolidayDoge.sol - Resolved Issue #1 - Low
Description: The owner could use the lock() function in order to temporarily set ownership to address(0). Ownership is restored after the duration of time determined by the owner has passed and they use the unlock() function.
Risk/Impact: The unlock function has the potential to be used after ownership has been set to address(0), which will restore ownership to the original owner that initially created the ownership lock. This can be used in a nefarious way by the project team to restore ownership and change fee structures.
Recommendation: We recommend that the unlock function be modified to set the previous owner variable equal to address(0) at the end of the unlock function to prevent it from being used more than once per lock.
Resolution: The team has implemented the solution described above.
External Threat Results
Vulnerability Category | Notes | Result |
---|---|---|
Arbitrary Storage Write | N/A | PASS |
Arbitrary Jump | N/A | PASS |
Centralization of Control | WARNING | |
Delegate Call to Untrusted Contract | N/A | PASS |
Dependence on Predictable Variables | N/A | PASS |
Deprecated Opcodes | N/A | PASS |
Ether Thief | N/A | PASS |
Exceptions | N/A | PASS |
External Calls | N/A | PASS |
Integer Over/Underflow | N/A | PASS |
Multiple Sends | N/A | PASS |
Suicide | N/A | PASS |
State Change External Calls | N/A | PASS |
Unchecked Retval | N/A | PASS |
User Supplied Assertion | N/A | PASS |
Critical Solidity Compiler | N/A | PASS |
Overall Contract Safety | PASS |
Function Graph
Inheritance Chart
Functions Overview
($) = payable function
# = non-constant function
+ [Int] IERC20
- [Ext] totalSupply
- [Ext] balanceOf
- [Ext] transfer #
- [Ext] allowance
- [Ext] approve #
- [Ext] transferFrom #
+ [Lib] SafeMath
- [Int] add
- [Int] sub
- [Int] sub
- [Int] mul
- [Int] div
- [Int] div
- [Int] mod
- [Int] mod
+ Context
- [Int] _msgSender
- [Int] _msgData
+ [Lib] Address
- [Int] isContract
- [Int] sendValue #
- [Int] functionCall #
- [Int] functionCall #
- [Int] functionCallWithValue #
- [Int] functionCallWithValue #
- [Prv] _functionCallWithValue #
+ Ownable (Context)
- [Pub] #
- [Pub] owner
- [Pub] renounceOwnership #
- modifiers: onlyOwner
- [Pub] transferOwnership #
- modifiers: onlyOwner
- [Pub] geUnlockTime
- [Pub] lock #
- modifiers: onlyOwner
- [Pub] unlock #
+ [Int] IUniswapV2Factory
- [Ext] feeTo
- [Ext] feeToSetter
- [Ext] getPair
- [Ext] allPairs
- [Ext] allPairsLength
- [Ext] createPair #
- [Ext] setFeeTo #
- [Ext] setFeeToSetter #
+ [Int] IUniswapV2Pair
- [Ext] name
- [Ext] symbol
- [Ext] decimals
- [Ext] totalSupply
- [Ext] balanceOf
- [Ext] allowance
- [Ext] approve #
- [Ext] transfer #
- [Ext] transferFrom #
- [Ext] DOMAIN_SEPARATOR
- [Ext] PERMIT_TYPEHASH
- [Ext] nonces
- [Ext] permit #
- [Ext] MINIMUM_LIQUIDITY
- [Ext] factory
- [Ext] token0
- [Ext] token1
- [Ext] getReserves
- [Ext] price0CumulativeLast
- [Ext] price1CumulativeLast
- [Ext] kLast
- [Ext] mint #
- [Ext] burn #
- [Ext] swap #
- [Ext] skim #
- [Ext] sync #
- [Ext] initialize #
+ [Int] IUniswapV2Router01
- [Ext] factory
- [Ext] WETH
- [Ext] addLiquidity #
- [Ext] addLiquidityETH ($)
- [Ext] removeLiquidity #
- [Ext] removeLiquidityETH #
- [Ext] removeLiquidityWithPermit #
- [Ext] removeLiquidityETHWithPermit #
- [Ext] swapExactTokensForTokens #
- [Ext] swapTokensForExactTokens #
- [Ext] swapExactETHForTokens ($)
- [Ext] swapTokensForExactETH #
- [Ext] swapExactTokensForETH #
- [Ext] swapETHForExactTokens ($)
- [Ext] quote
- [Ext] getAmountOut
- [Ext] getAmountIn
- [Ext] getAmountsOut
- [Ext] getAmountsIn
+ [Int] IUniswapV2Router02 (IUniswapV2Router01)
- [Ext] removeLiquidityETHSupportingFeeOnTransferTokens #
- [Ext] removeLiquidityETHWithPermitSupportingFeeOnTransferTokens #
- [Ext] swapExactTokensForTokensSupportingFeeOnTransferTokens #
- [Ext] swapExactETHForTokensSupportingFeeOnTransferTokens ($)
- [Ext] swapExactTokensForETHSupportingFeeOnTransferTokens #
+ HolidayDoge (Context, IERC20, Ownable)
- [Pub] #
- [Pub] name
- [Pub] symbol
- [Pub] decimals
- [Pub] totalSupply
- [Pub] balanceOf
- [Pub] transfer #
- [Pub] allowance
- [Pub] approve #
- [Pub] transferFrom #
- [Pub] increaseAllowance #
- [Pub] decreaseAllowance #
- [Pub] isExcludedFromReward
- [Pub] totalFees
- [Pub] deliver #
- [Pub] reflectionFromToken
- [Pub] tokenFromReflection
- [Pub] excludeFromReward #
- modifiers: onlyOwner
- [Ext] includeInReward #
- modifiers: onlyOwner
- [Prv] _transferBothExcluded #
- [Pub] excludeFromFee #
- modifiers: onlyOwner
- [Pub] includeInFee #
- modifiers: onlyOwner
- [Ext] setTaxFeePercent #
- modifiers: onlyOwner
- [Ext] setLiquidityFeePercent #
- modifiers: onlyOwner
- [Ext] setMaxTxPercent #
- modifiers: onlyOwner
- [Ext] setMarketingFeePercent #
- modifiers: onlyOwner
- [Ext] setMarketingWallet #
- modifiers: onlyOwner
- [Pub] setSwapAndLiquifyEnabled #
- modifiers: onlyOwner
- [Ext] changeNumTokensSellToAddToLiquidity #
- modifiers: onlyOwner
- [Ext] ($)
- [Prv] _reflectFee #
- [Prv] _getValues
- [Prv] _getTValues
- [Prv] _getRValues
- [Prv] _getRate
- [Prv] _getCurrentSupply
- [Prv] _takeLiquidity #
- [Prv] calculateTaxFee
- [Prv] calculateLiquidityFee
- [Prv] removeAllFee #
- [Prv] restoreAllFee #
- [Pub] isExcludedFromFee
- [Prv] _approve #
- [Prv] _transfer #
- [Prv] swapAndLiquify #
- modifiers: lockTheSwap
- [Prv] swapTokensForEth #
- [Prv] addLiquidity #
- [Prv] _tokenTransfer #
- [Prv] _transferStandard #
- [Prv] _transferToExcluded #
- [Prv] _transferFromExcluded #