Linkswap security record

The clone-and-own approach involves copying and adjusting open source code at one's own discretion. From the development perspective, it is initially beneficial as it reduces the amount of effort. However, from the security perspective, it involves some risks as the code may not follow the best practices, may contain a security vulnerability, or may include intentionally or unintentionally modified upstream libraries. In particular, the file `SafeMathLinkswap.sol` appears to be cloned from another project.

If the price has changed significantly over the `windowSize`, older values may not be helpful at determining the current value of a coin. For example, if the average price has significantly increased over 24h, then `consult` will return a higher `out` amount than desired (as the older low values will lower the average price).

1. In order to avoid faulty transactions that use default values for arguments, we recommend checking that address arguments are non-zero in the following functions: 1. `LinkswapFactory.createPair`; 1. `LinkswapPriceOracle.constructor`; 1. `YFLPurchaser.constructor`; 1. `yYFL.constructor`. 1. For the functions `getAmountOut` and `getAmountIn` in `LinkswapLibrary.sol`, it should check if the input variable `tradingFeePercent` is smaller than `1e6`. 1. For the function `getAmountsOut` and `getAmountsIn` in `LinkswapLibrary.sol`, it should check if each of the array element in the input variable `path` is not equal to `0x0`. 1. In function `swap` of `LinkswapPair.sol`, it should check if `to` is a `ILinkswapCallee` contract. 1. Although the function `parseStringData` in `SafeERC20Namer.sol` appears not to be used anywhere in this project, it should check if `b` contains more than `64` bytes, and also should check if `b` contains exactly `charCount + 64` bytes. 1. On `L18` in `UQ112x112.sol`, it should check if `uint112 y` is not equal to `0`.