Unruggable audit details

Total Prize Pool: $38,000 in USDC
- HM awards: $30,500 in USDC
- QA awards: $1,300 in USDC
- Judge awards: $5,700 in USDC
- Scout awards: $500 in USDC
Read our guidelines for more details
Starts December 6, 2024 20:00 UTC
Ends December 20, 2024 20:00 UTC

Note re: risk level upgrades/downgrades

Two important notes about judging phase risk adjustments:

High- or Medium-risk submissions downgraded to Low-risk (QA)) will be ineligible for awards.
Upgrading a Low-risk finding from a QA report to a Medium- or High-risk finding is not supported.

As such, wardens are encouraged to select the appropriate risk level carefully during the submission phase.

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Please review the following confidentiality requirements carefully, and if anything is unclear, ask questions in the private audit channel in the C4 Discord.

Automated Findings / Publicly Known Issues

Note for C4 wardens: Anything included in this Automated Findings / Publicly Known Issues section is considered a publicly known issue and is ineligible for awards.

Zenith Audit Report

Scope

See scope.txt

Files in scope

File	Logic Contracts	Interfaces	nSLOC	Libraries used
/contracts/eth/EthVerifierHooks.sol	1	****	25
/contracts/linea/ILineaRollup.sol	****	1	3
/contracts/linea/LineaVerifier.sol	1	****	31
/contracts/linea/LineaVerifierHooks.sol	1	****	48
/contracts/nitro/IRollupCore.sol	****	1	17
/contracts/nitro/NitroVerifier.sol	1	****	69
/contracts/op/OPFaultGameFinder.sol	1	3	43
/contracts/op/OPFaultVerifier.sol	1	2	62
/contracts/op/OPVerifier.sol	1	1	50
/contracts/scroll/ScrollVerifier.sol	1	1	31
/contracts/scroll/ScrollVerifierHooks.sol	1	1	108
/contracts/AbstractVerifier.sol	1	****	32	@openzeppelin/contracts/access/Ownable.sol
/contracts/GatewayFetchTarget.sol	1	****	44
/contracts/GatewayFetcher.sol	1	****	293
/contracts/GatewayRequest.sol	2	****	88
/contracts/GatewayVM.sol	1	****	442	forge-std/console.sol
/contracts/IGatewayProtocol.sol	****	1	4
/contracts/IGatewayVerifier.sol	****	1	6
/contracts/IVerifierHooks.sol	****	1	6
/contracts/RLPReaderExt.sol	1	****	21
/contracts/ReadBytesAt.sol	1	****	10
Totals	17	13	1433

Files out of scope

See out_of_scope.txt

File
./contracts/SelfVerifier.sol
./contracts/TrustedVerifier.sol
./contracts/eth/MerkleTrie.sol
./contracts/eth/SecureMerkleTrie.sol
./contracts/linea/Mimc.sol
./contracts/linea/SparseMerkleProof.sol
./contracts/linea/UnfinalizedLineaVerifier.sol
./contracts/nitro/DoubleNitroVerifier.sol
./contracts/op/ReverseOPVerifier.sol
./contracts/polygon/PolygonPoSVerifier.sol
./contracts/taiko/TaikoVerifier.sol
./contracts/zksync/Blake2S.sol
./contracts/zksync/IZKSyncSMT.sol
./contracts/zksync/ZKSyncSMT.sol
./contracts/zksync/ZKSyncVerifier.sol
./contracts/zksync/ZKSyncVerifierHooks.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/interfaces/IDisputeGame.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/interfaces/IDisputeGameFactory.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/interfaces/IInitializable.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/lib/LibPosition.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/lib/LibUDT.sol
./lib/optimism/packages/contracts-bedrock/src/dispute/lib/Types.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/Bytes.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/Encoding.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/Hashing.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/Types.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/rlp/RLPErrors.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/rlp/RLPReader.sol
./lib/optimism/packages/contracts-bedrock/src/libraries/rlp/RLPWriter.sol
./test/components/GatewayFetcher.t.sol
./test/components/GatewayVM.t.sol
./test/examples/ens/L1Resolver.sol
./test/examples/ens/L2Storage.sol
./test/examples/self/Backend.sol
./test/examples/self/Frontend.sol
./test/gateway/FixedOPFaultGameFinder.sol
./test/gateway/SlotDataContract.sol
./test/gateway/SlotDataPointer.sol
./test/gateway/SlotDataReader.sol
Totals: 39

Scoping Q & A

Question	Answer
ERC20 used by the protocol	No
ERC721 used by the protocol	No
ERC777 used by the protocol	Yes/No
ERC1155 used by the protocol	No
Chains the protocol will be deployed on	Ethereum, Arbitrum, Base, Optimism, Scroll, Other

External integrations (e.g., Uniswap) behavior in scope:

Question	Answer
Enabling/disabling fees (e.g. Blur disables/enables fees)	No
Pausability (e.g. Uniswap pool gets paused)	Yes
Upgradeability (e.g. Uniswap gets upgraded)	Yes

Additional context

Please list all the other chains you plan on deploying to:

Iteratively over time, numerous. Verifiers for these chains will be covered in later audits.

For this audit, we are covering Arbitrum, Base, Linea, Optimism, and Scroll. There are no explicit deployments on these chains in the code scope but i've highlighted them given the nature of the codebase.

Are there contracts that are required to comply with any EIPs?

contracts/GatewayFetchTarget.sol - ERC-3668

Areas of concern

Correctness of the verification path for each of the five in-scope chains.
Confirmation that the Virtual Machine OP codes result in expected outputs.
Confirmation that the non-existence of data is appropriately verified/handled.
Verification of the trustless-ness of the solution.

All trusted roles of the protocol

Verifier contract owner can modify the Gateway URLs.

Main invariants

Only correct proofs are accepted. Invalid or unproven inputs are rejected.
No control by any party can allow for modifications that negate other invariants.

Running tests

Testing instructions can be reviewed here.

Miscellaneous

Employees of Unruggable and employees' family members are ineligible to participate in this audit.

Code4rena's rules cannot be overridden by the contents of this README. In case of doubt, please check with C4 staff.

code-423n4/2024-12-unruggable