Metamorphic Contracts and Deployment Scripts

These contracts are for test purposes and should not be used in production environments.

Relevant Information

• Metamorphic Smart Contracts: Is EVM Code Truly Immutable? (MixBytes Blog)
• 0xOwenThurm Twitter Thread

Prerequisites

• foundry.toml does not affect contracts deployed to Anvil.
• EVM Version: Shanghai should be selected. Otherwise, selfdestruct only sends ether and contracts are not destroyed. This must be specified in Anvil:
  anvil --hardfork shanghai
• A new contract (MetaDeployer) is deployed with CREATE. This contract has a CREATE2 function to create a factory contract (MutDeployer).
• The MutDeployer contract has 3 functions:
  1. Deploys a V1 version of an implementation contract.
  2. Deploys a V2 version of an implementation contract.
  3. Destroys (selfdestructs) itself.
• The two implementation contracts each have arbitrary functions and variables, but both must have a destroy (selfdestruct) function.

How to Deploy the Metamorphic Contracts

1. The MetaDeployer contract is deployed at address A.
   It has a function to deploy MutDeployer using CREATE2.
2. MetaDeployer deploys the MutDeployer contract using CREATE2 at address B.
   CREATE2 is used so that the same contract can be redeployed to the same address after MutDeployer is destroyed. This is necessary because MutDeployer will deploy V2 of the implementation contract, and to deploy V2 to the same address as V1, the nonce of MutDeployer must be reset. Once reset, MutDeployer can deploy V2 to the same address as the destroyed V1 implementation contract.
3. MutDeployer deploys the V1 implementation contract at address C.
4. V1 implementation contract is destroyed.
   There is no contract at address C at this point.
5. MutDeployer is destroyed.
   There is no contract at address B at this point.
6. MetaDeployer deploys the same MutDeployer contract using CREATE2 at address B again.
   The nonce is now reset.
7. V2 implementation contract is deployed at the same address where V1 was deployed (address C).
8. This process ensures that the V2 implementation contract is deployed at the same address as the V1 implementation contract, maintaining consistency in contract addresses.

Running the Scripts

The reason for having a two-part script is to complete the destroy process. selfdestruct is completed at the end of a block.

The addresses deployed in the first part of the script are saved to a directory called vmreadwritefile.

Scripts need to be run separately:

anvil --hardfork shanghai

forge script MetaDeployerScript --broadcast --rpc-url localhost:8545 --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80 --sig "run1()" -vvvvv
forge script MetaDeployerScript --broadcast --rpc-url localhost:8545 --private-key 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80 --sig "run2()" -vvvvv

Running the tests

Test file is not complete nad outputs collision error. I couldn't find a way to complete the selfdestruct transaction yet.