Golden recommended reading | The secret of the money printing machine: the most complete technical details of USDT issuance.

Recently, I heard that Tether (USDT) on Ethereum has been frequently issued. For the purpose of learning, we audited Tether’s smart contract (TetherToken) source code and USDT issuance-related call events on  etherscan . This article records the analysis process.

The following is the USDT issuance function of the TetherToken smart contract:

It can be seen that the  owner  account of the TetherToken contract needs to call the  issue(uint) issue function to issue additional USDT, and an  Issue(amount) issue event will be thrown after the issue is successful.

Jinse Finance contract market analysis | BTC consolidated in a narrow range below $12,000: According to the Huobi BTC perpetual contract market, as of 18:00 today (GMT+8), the BTC price was temporarily reported at $11,825 (+0.66%), 20:00 00 (GMT+8) settlement funding rate is 0.010000%.

BTC is currently fluctuating in the range of $11,600-$11,900. According to the Huobi delivery contract data, BTC’s contract turnover in the current quarter has shrunk, the open interest has decreased slightly, the proportion of elite longs has decreased slightly, and the positive premium of the contract in the current quarter has remained stable. BTC is consolidating below the previous high point, and the open interest remains high, and it is still accumulating strength for subsequent directional fluctuations.

The price of USDT on Huobi Global OTC is 6.91 yuan, with a premium rate of -0.74%. [2020/8/7]

Let’s take a look at the screenshot of the most recent additional record:

Golden Evening News | A list of important news on the evening of April 10: 12:00-21:00 Keywords: central bank digital currency, Ministry of Industry and Information Technology, BSV, Bitcoin halving

1. Director of the central bank's general office: the central bank's digital currency is advancing in an orderly manner.

2. The National Development and Reform Commission and the Central Cyberspace Administration of China: Accelerate the common technologies of digital transformation and support the integration and innovation of technologies such as blockchain.

3. The Ministry of Industry and Information Technology issued a draft for comments on network data security, with blockchain as a key area.

4. Google Trends shows a surge in Google searches for "Bitcoin halving" this year.

5. Japanese blockchain developer Chainbow launched a private information protocol based on BSV.

6. Chen Zhengchang: More than half of Mexicans use cryptocurrencies to shop online.

7. CSW attorney slams court order for 'personal attack'

8. The chairman of the NEM Foundation announced a six-month paid vacation, which caused dissatisfaction in the community. [2020/4/10]

Transaction Hash: 0xdd108cd36fbeaab03b29ac46d465ad9824618d683268681d3206bd78302e0d71

Golden Noon News | March 23 at noon important updates: 7:00-12:00 Keywords: Ministry of Industry and Information Technology, Blockchain and New Coronary Pneumonia, Risk Avoidance

1. The Ministry of Industry and Information Technology launched a special action to complete the IPv6 transformation of blockchain services and other products.

2. South Korea may announce market measures of 27 trillion won tomorrow.

3. The safe-haven performance of U.S. Treasury bonds outperformed Bitcoin and gold during the COVID-19 period.

4. The gradual decoupling of Bitcoin from Wall Street usually heralds a recovery in the Bitcoin market.

5. Blockchain can help the medical supply chain cope with the five major trust challenges brought about by the new crown pneumonia.

6. Algorand and Tether have been integrated.

7. BTC fluctuates downward, volume and price fall, and still need to wait for the bottom opportunity.

8. Huobi Global_API has shortened the inquiry range of "completely canceled" orders to 2 hours.

9. Bitcoin fluctuated in a wide range, with the highest quotation at $6138 and the lowest quotation at $5686. [2020/3/23]

Analysis | Golden disk: XRP surpasses ETH to become the second largest digital currency by market value: Golden disk exclusive analysis: XRP rose 60% today, and its market value just surpassed ETH, reaching 24 billion US dollars. Recently, XRP issued an announcement claiming that PNC Bank, one of the top ten banks in the United States, adopted one of its own technologies. Stimulated by the news, XRP started a magical journey, and the price soared all the way, from $0.26 in just 4 days , soared to $0.79, with an amplitude of 200%, making its market value surpass ETH and becoming the second largest digital currency.

From the multi-cycle chart, we can see that there are many major cycles here, but the short-term deviation is large and the derailment is serious. It is necessary to wait for the track to change. It is not suitable to chase higher in the short-term. [2018/9/22]

It can be seen that in the transaction details above, the  issue(uint)  issuance function of the TetherToken contract is not called, but the  confirmTransaction(uint)  function of the MultiSigWallet contract is called to complete the issuance operation.

Golden Finance News: The Central Bank of Lithuania is providing new ICO guidance for those organizations or individuals seeking to conduct ICOs in the country. [2017/10/13]

There are two things to note:

TetherToken contract call analysis

Let's first look at the implementation of the  confirmTransaction(uint)  function of the MultiSigWallet contract

To call the  confirmTransaction(uint)  function to confirm and execute the transaction, the following conditions must be met

submitTransaction(address,uint,bytes)  will call the  addTransaction(address,uint,bytes)  function inside the contract, and its implementation is as follows:

The final complete submission -> confirmation operation process is as follows:

1. Call the  submitTransaction (address,uint,bytes)  function to submit the transaction and pass in the parameters: contract-address, eth-value, payload. Note: Committing a transaction includes a transaction confirmation.

Submission event -> Confirmation event is sent in turn.

2. To call  confirmTransaction(uint)  to confirm and execute the transaction, 3 different  owner  accounts are required to complete the final confirmation.

Send the Confirmation event in turn -> execute the event generated by  payload  (satisfying the number of confirmations)-> Execution event.

The TetherToken cross-contract call is shown in the figure below:

USDT issuance analysis

Continue to look at the call event of this additional transaction, which just meets the event generated by calling the  confirmTransaction(uint)  function.

Call parameters can be seen by querying transactionId

Translates to the following pseudocode:

So where does the USDT of the  Bitfinex: MultiSig 2  address come from? According to the transactionId, continue to trace a transaction forward to find the transaction that actually issued USDT for the  Bitfinex: MultiSig 2  address:

Transaction Hash: 0xb467ea92b5c0095b1a96f35eb466b239c13e5b0b3f493e3e452f832d99830d6b

This is the real operation of issuing additional USDT for Bitfinex: MultiSig 2  addresses.

USDT issuance is shown in the following figure:

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