JALAN RUSAK: Yfswap

Yfswap

Introduction

Given the opportunity to review the YFETH smart contract source code, we in the report outline our systematic approach to evaluate potential security issues in the smart contract implementation, expose possible semantic inconsistencies between smart contract code and design document, and provide additional suggestions or recommendations for improvement. Our results show that the given branch of YFETH can be further improved due to the presence of several issues related to either security or performance. This document outlines our audit results.

About Yfswap?

Yfswap is an AMM based Dex created with the intention of providing a one stop solution,DeFi farming, staking and a Dex Exchange all in one. YFBTC and YFETH will be using LP pools from Uniswap until the LP pools has grown large enough. A migration will be voted by users if users would want the full benefits of earning the swapping fees at YFSwap. Uniswap shares its swap fees with its own core investors, while YFSwap users will be able to earn full amount of the swap fees. Even more than Sushiswap.

YFBTC & YFETH are a non-inflationary cryptocurrency that follows the same principles of its legacy with it being completely decentralized. YFETH is the native to YFSwap for AMM Pool rewards.

As food-meme DeFi tokens slowly shows that it is not sustainable with it unlimited farming, YFBTC and YFETH is the solution for users to confidently hold for long term. Giving alternative to ETH and BTC users to hold a non-inflationary cryptocurrency while farming.

Methodology

To standardize the evaluation, we define the following terminology based on OWASP Risk Rating Methodology:

• Likelihood represents how likely a particular vulnerability is to be uncovered and exploited in the wild;

• Impact measures the technical loss and business damage of a successful attack;

• Severity demonstrates the overall criticality of the risk.

YFBTC (21,000 Total Supply)

UNISWAP address of DeFi Bitcoin YFBTC DeFi Yield farming will be at YFBTC.net

FREE YFBTC FOR CLAIM INSTRUCTIONS ON YFBTC.NET

• The number of YFBTC Free Claim is 1,000. YFBTC will end the airdrop and tokens can be claimed by the 18th Oct 2020 with each user claiming 0.1 YFBTC, and is now listed on Uniswap decentralized exchange. Potential additional exchanges to be listed are Hotbit and Bilaxy.

USERS WHO WISH TO PURCHASE YFBTC VIA UNISWAP

• In order to start the Uniswap trading process, 1% of 21,000 YFBTC (210 YFBTC) will be sold in Uniswap in 3 stages, and 950 YFBTC is for initial private contributors that help fund the initial phase for YFSwap. Before purchasing, please confirm it is the correct YFBTC Contract address.

TOTAL DISTRIBUTION OF YFBTC

• YFBTC will be distributed in the spirit of YFI, only 5.5% Pre-mine, no Founder shares, no VC interest. simply equal-opportunity staking distribution to attract a broad and vision-aligned community to steward the future of the protocol and token. The total amount of YFBTC is 21,000.

WE DO NOT ENCOURAGE PURCHASE OF YFETH. BUT BETTER THAN RUG PULLS OR FOOD DEFI. But if you still want to proceed, click on participate in Campaign.

CROWDFUNDING & CLAIM FREE YFETH INSTRUCTIONS

• To qualify for the airdrop, your metamask wallet must EITHER have “300 UNI, 300 BITTO, 0.5 YFI, 300 BAL, 300 LINK, 300 BNB, 300 HT, 300 OKB, 300 BAND, 300 NXM”. YOU will be eligible for FREE 3 YFETH tokens.

• Use your Metamask wallet to send ETH to the crowdfunding address, Do NOT SEND FROM EXCHANGE.

• YFETH will be automatically sent to your source address according to the source address of your ETH via smart contract.

• Multiple ETH can be transferred, automatically aggregated

• The initial amount of YFETH is 75,000, and the number of YFETH Free airdrops is 39,125. Another 35,875 YFETH will be allocated for Crowdfunding to help maintain server and project sustainability and future development. But any YFETH left from crowdfunding will be burned and will NOT be kept by team or developers to ensure maximum decentralization of YFETH supply.

• YFETH will end the airdrop and tokens must be claimed before 16th Oct 2020. YFETH will also be listed on Uniswap decentralized exchange. Potential additional exchanges to be listed are Hotbit and Bilaxy.

CROWDFUNDING RULES

• The total amount of the first phase of crowdfunding is 8,500 YFETH, and the crowdfunding time: Starts Stage 1 from 7th Oct 2020 (UTC+8) to end at the 16th Oct 2020 (UTC+8) or until 550th ETH received.

• Crowdfunding price 1 ETH = 100 YFETH

• The end of the first round of crowdfunding is subject to the 85th ETH received by the crowdfunding address.

• The total amount of the second phase of crowdfunding is 12,375 YFETH, and the crowdfunding time: the 250th ETH received by the crowdfunding address to 11th Oct 2020 (UTC+8)

• Crowdfunding price 1 ETH = 75 YFETH

• The total amount of the second phase of crowdfunding is 12,375 YFETH, is subject to the 250th ETH received by the crowdfunding address.

• Crowdfunding price 1 ETH = 50 YFETH

• The total amount of the third phase of crowdfunding is 15,000 YFETH, is subject to the 550th ETH received by the crowdfunding address or until 16th Oct 2020 (UTC+8) whichever comes first

The quota is sorted by time, and tokens are issued, the earlier the participation, the greater the success rate. If the crowdfunding is completed you will receive YFETH. The purchase will be refunded automatically if the purchase is not successful. 1 address can only purchase up to 25 ETH to avoid monopolization and ensure decentralization of YFETH assets

TOTAL DISTRIBUTION OF YFETH

• The initial amount of YFETH is 75,000, and the number of YFETH Free airdrops is 39,125. Another 35,875 YFETH will be allocated for Crowdfunding to help maintain server and project sustainability and future development. If there is any YFETH left from crowdfunding or airdrops, it will be burned and will NOT be kept by team or developers to ensure maximum decentralization of YFETH supply. YFETH follows Constantinople ETH upgrade protocol.

• We reserve the right to cancel airdrops to users who we deem abusing the system. We hope to reserve this opportunity for other users.

• This airdrop enables machine learning to identify cheating. Those who are identified as cheaters will cancel the airdrop, and those who participate in the recognition will return ETH

YFETH DeFi ROI ESTIMATION

This is based on the Scenario of USDT/ETH, DAI/ETH

YFETH is $5
Per Block Yield Farming rewards are 0.4 YFETH ( First month)
Assuming 7.5(2.5+2.0+1+1+1) weightage = 0.4/7.5 = 0.05333

BITTO/ETH 2.5x

YFETH/ETH 2.0x

USDT/ETH

DAI/ETH

USDC/ETH

15,000 YFETH will be used for yield farming(currently, only around 8000 distributed. 1st rank contract holding will all be burned after 18th) What this means is that the ROI will be higher than stated.

https://etherscan.io/token/0xE52294152805e304803c93b700266DDFE99eaB32#balances

15,000 YFETH @ $5 = $75000. LP is a pair of same value. so each side of the pair is valued at $75,000 = $150,000 total LP pair value
Per hour 0.0533*240 = 12.8(Total Block reward per hour)*$5 YFETH value= $64 is the estimated reward in YFETH VALUE per hour.

ESTIMATION FARMING YFETH PER HOUR ROI ACCORDING TO THE ABOVE SCENARIO

$64/$150,000 = 0.042% (YFI/ETH) 1x
2.5x*0.042% = 0.106% (BITTO/ETH) 2.5x
2.0x*0.042% = 0.084% (YFETH/ETH) 2.0x

*Take note this is an estimation. Value may differ based on the variables mentioned.

YFBTC ROI ESTIMATION(YFBTC.NET IS BASED ON 2000USD)

This is based on the Scenario of YFBTC at the value of $400

Per Block the Yield Farming rewards are 0.004559 YFBTC
Assuming 4.75 weightage = 0.004559/4.75 = 0.0010

150 YFBTC will be used for yield farming (Based on current amount placed in Uniswap)

150 @ $400 = $60,000. LP is a pair of same value. so each side of the pair is valued at $60,000*2 = $120,000 total LP pair value
Per block 0.0010*240(4 blocks a minute * 60 minutes an hour)= 0.24(Total Block reward per hour)*$400 YFBTC Value= $96 is the estimated reward in YFBTC VALUE per hour.

ESTIMATION FARMING YFBTC PER HOUR ROI ACCORDING TO THE ABOVE SCENARIO

$96/$120,000 = 0.08*1.5x = 0.12% (wBTC/wETH) 1.5x
$96/$120,000 = 0.08*1.25x = 0.1% (BITTO/ETH) 1.25x
$96/$120,000 =0.08*2x = 0.16% (YFBTC/ETH) 2.0x

Take note this is an estimation. Value may differ based on the variables mentioned.

You can calculate using the hourly ROI % above and obtain ROI MULTIPLIED BY DAILY, MONTHLY OR YEARLY with a figure.

Example 0.12% hourly on (wBTC/wETH) pairing with 200 USD locked assets on monthly.

0.12% * 24 hours * 30 days = 86.4% * 200 USD = 172 USD after 1 month.

Team rewards

We are an anonymous group of developers who believe in the future of decentralized autonomous organizations (DAO). We do not believe in pre-sale or tokens pre-reserved for the team. The team will receive a relatively low share of rewards during the entire YFETH & YFBTC farming period, which is 2.5%.

Conclusion

In this audit, we thoroughly analyzed the YFETH design and implementation. Overall, YFETH presents an evolutional improvement based on Uniswap and provide extra incentives to liquidity providers. Our impression is that the current code base is well organized. Meanwhile, we need to emphasize that smart contracts as a whole are still in an early, but exciting stage of development. To improve this report, we greatly appreciate any constructive feedbacks or suggestions, on our methodology, audit findings, or potential gaps in scope/coverage