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Impact Analysis of Neutering SELFDESTRUCT - Dev Update #2

This is the second update for my CDAP Project, which is about analyzing the existing uses of the SELFDESTRUCT opcode in Ethereum.

Progress since last update

Since the last update, I have focused on analyzing existing uses of redeployed contracts, which is a contract that is deployed at the same address as a selfdestructed contract. Since redeploying a contract will no longer be possible if SELFDESTRUCT is neutered, this is an interesting use case to analyze.

The analysis revealed that disabling or neutering SELFDESTRUCT opens a security risk to uninformed users of a contract used by Pine Finance. In short, users of this contract send tokens to an predetermined address called a vault. Relayers then trigger a function in the PineCore contract to create a new contract at this predetermined address using CREATE2, which executes a trade and then self destructs. Under the current behaviour, it is possible for a user to use the same vault several times. If SELFDESTRUCT is neutered, however, this would no longer be possible. In fact, if a user then tried to send tokens to a used vault, anyone could steal the tokens in the vault.

The full analysis is hosted here.

What to do next

Based on the analysis, I will suggest trying to preserve SELFDESTRUCT when switching to Verkle trees. There are several ways this may be done, so I will write down the different options as diffs to the current Verkle tree proposal and evaluate them.

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Albus Dompeldorius CDAP - Dev Update #7

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Oct 26, 2021
Springrollup: A zk-rollup that allows a sender to batch an unlimited number of transfers with only 6 bytes of calldata per batch

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Oct 20, 2021
Albus Dompeldorius CDAP - Dev Update #5

This is the fifth update for my work in the CDAP. What I have done since last update Since my last update, I have been working on my zk-rollup concept, which allows for greatly reduced calldata usage while still preserving the same security of zk-rollups. The document is now expanded with more details about deposits, withdrawals, calldata estimates and examples. Anyone familiar with how zk-rollups work should now hopefully be able to grasp the main idea in my proposal. The reason I haven't posted to ethresear.ch yet, is that I want to implement an optimization first. (see below) What I will do next I am currently working on an optimization which would allow even less calldata usage. The current proposal uses 8 bytes of calldata for a batch of up to 65536 transfers from the same sender, but with the extra optimization this will be reduced to 6 bytes for a batch of an unlimited amount of transfers from the same sender. Once this is done, I will post the proposal on ethresear.ch to get some feedback on the proposal. I will reach out to zk-people to try to collaborate on an implementation.

Oct 12, 2021
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