From the evening of March 18 to March 19, the community had a lot of discussions on the “double flower” event of filecoin. After confirming with the official filecoin and other platforms, it was found that there was no “double flower” problem in filecoin and the filecoin chain was safe.
“Shuanghua” is actually a strange word for most people.
“Shuanghua” is also known as double payment, which means double spending. It means that in the digital currency system, due to the duplication of data, the same digital asset may be reused due to improper operation.
What does that mean?
First of all, double payment is possible only in the digital currency trading system. When we trade in cash, there is no problem of double payment.
Because you transferred 5000 yuan to me on wechat. After I received it, 5000 yuan will be less in your account and 5000 yuan will be more in my account. That is to say, in the cash transaction, the successful transaction of assets means that the transfer of assets is actually completed.
However, in the world of blockchain, it’s not the same. Because the transactions are digital assets, these assets are actually the transmission of some virtual information. Because a transaction record has a time window from generation to link to the blockchain, what we call “double flower” actually takes advantage of “time difference”.
If the “double flower” is realized, the attacker can make the spent digital assets return to his account.
It’s just like some people use a pay phone to cunningly wear a string on the coin. Although they toss the coin, the actual transaction has not been completed. He can use the string to take out the coin after making a phone call, and then he can make countless phone calls with this coin.
Conflict transaction flow chart
Although “Shuanghua” can make people get double income, there are few successful “Shuanghua” events in the history of blockchain.
In the filecoin network, it never happened!
The whole story of filecoin Shuanghua incident
On the evening of March 18, a user recharged fil in a digital asset platform. After the double flower operation, he could still receive the same amount of fil. That is to say, a user recharged 61000 fils in a digital asset platform, resulting in 120000 fils.
At this time, some users think that it is caused by the double flower event in the filecoin network, but the actual situation is that the digital asset platform has made a mistake in its own bookkeeping, that is to say, this is not the problem of the filecoin chain!
However, in response to the incident, the lotus team also conducted a thorough investigation and determined that there were no problems related to the filecoin network and RPC api code, that is, there was no double flower problem in the chain itself, and there was no error in the API code.
As for the transaction records of the digital asset platform, they are also being revised. At the same time, the official team of filecoin is also reviewing the recharge processing logic in the accounting system of the relevant platform to correct their API usage.
Why is there a misunderstanding of “two flowers of filecoin”?
The so-called “double flower” event of filecoin is a farce. However, why do some communities still misunderstand this event? Since there is no problem with the filecoin chain and the API code, where is the problem?
The core of this problem is that some digital asset platforms and some filecoin blockchain browsers do not use lotus’s chain state checking API properly. When dealing with multiple similar messages, the processing method is different from what is expected.
Misunderstanding the output of lotus API will lead the accounting system to count the original message and replacement message as the same sender and receiver. In short, it is the way people check the chain, which will show that the message has been processed twice, resulting in misunderstanding.
Specifically, some digital asset platforms use a wrong way to handle the chain state – calling chaingetblockmessages on each block of tipset, and then calling stategetreceive on these messages.
When stategetreceive is called on two similar messages (one is executed and the other is skipped), it will provide the same result to people, which will lead to the illusion that both messages are executed.
From the evening of March 18 to the early morning of March 19, since receiving the feedback of the incident, the relevant team of filecoin immediately verified the relevant information, and timely shared and updated the latest information in twitter, slack, official website blog and other channels.
First of all, facts have proved that the filecoin chain is safe and there is no problem, and the “Shuanghua” incident is just an oolong and farce!
Secondly, the official team of filecoin attaches great importance to the feedback problems from the community, and the behavior of timely solving problems and assisting the community to solve problems when encountering problems is highly commendable. This also proves that “filecoin belongs to the community, belongs to all of us, and is the joint efforts of all of us to make the filecoin network better and better”.
Finally, IPFs & filecoin is in an era of vigorous development and explosive growth of big data. In this era, there are trillions of outlets for distributed storage technology. Every IPFs & filecoin participant will take advantage of the east wind of distributed storage and soar in the sky.