op-challenger

op-challenger

The op-challenger is a modular op-stack challenge agent written in golang for dispute games including, but not limited to,attestation games, fault games, and validity games. To learn more about dispute games, visit the fault proof specs.

Quickstart

To build the op-challenger, run make (which executes the make build Makefile target). To view a list of available commands and options, run ./bin/op-challenger --help.

Usage

op-challenger is configurable via command line flags and environment variables. The help menu shows the available config options and can be accessed by running ./op-challenger --help.

Running with Cannon on Local Devnet

To run op-challenger against the local devnet, first clean and run the devnet from the root of the repository.

make devnet-clean
make devnet-up

Then build the op-challenger with make op-challenger.

Run the op-challenger with:

DISPUTE_GAME_FACTORY=$(jq -r .DisputeGameFactoryProxy .devnet/addresses.json)
./op-challenger/bin/op-challenger \
  --trace-type cannon \
  --l1-eth-rpc http://localhost:8545 \
  --rollup-rpc http://localhost:9546 \
  --game-factory-address $DISPUTE_GAME_FACTORY \
  --datadir temp/challenger-data \
  --cannon-rollup-config .devnet/rollup.json  \
  --cannon-l2-genesis .devnet/genesis-l2.json \
  --cannon-bin ./cannon/bin/cannon \
  --cannon-server ./op-program/bin/op-program \
  --cannon-prestate ./op-program/bin/prestate.json \
  --l2-eth-rpc http://localhost:9545 \
  --mnemonic "test test test test test test test test test test test junk" \
  --hd-path "m/44'/60'/0'/0/8" \
  --num-confirmations 1

The mnemonic and hd-path above is a prefunded address on the devnet. The challenger will monitor dispute games and respond to any invalid claims by posting the correct trace as the counter-claim. The commands below can then be used to create and interact with games.

Subcommands

The op-challenger has a few subcommands to interact with on-chain fault dispute games. The subcommands support game creation, performing game moves, and viewing fault dispute game data. They should not be used in production and are intended to provide convenient manual testing.

create-game

./bin/op-challenger create-game \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-address <GAME_FACTORY_ADDRESS> \
  --output-root <OUTPUT_ROOT> \
  --l2-block-num <L2_BLOCK_NUM> \
  <SIGNER_ARGS>

Starts a new fault dispute game that disputes the latest output proposal in the L2 output oracle.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_FACTORY_ADDRESS - the address of the dispute game factory contract on L1.
• OUTPUT_ROOT a hex encoded 32 byte hash that is used as the proposed output root.
• L2_BLOCK_NUM the L2 block number the proposed output root is from.
• SIGNER_ARGS arguments to specify the key to sign transactions with (e.g --private-key)

Optionally, you may specify the game type (aka "trace type") using the --trace-type flag, which is set to the cannon trace type by default.

move

The move subcommand can be run with either the --attack or --defend flag, but not both.

./bin/op-challenger move \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-address <GAME_ADDRESS> \
  --attack \
  --parent-index <PARENT_INDEX> \
  --claim <CLAIM> \
  <SIGNER_ARGS>

Performs a move to either attack or defend the latest claim in the specified game.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_ADDRESS - the address of the dispute game to perform the move in.
• (attack|defend) - the type of move to make.
  • attack indicates that the state hash in your local cannon trace differs to the state hash included in the latest claim.
  • defend indicates that the state hash in your local cannon trace matches the state hash included in the latest claim.
• PARENT_INDEX - the index of the parent claim that will be countered by this new claim. The special value of latest will counter the latest claim added to the game.
• CLAIM - the state hash to include in the counter-claim you are posting.
• SIGNER_ARGS arguments to specify the key to sign transactions with (e.g --private-key)

resolve-claim

./bin/op-challenger resolve-claim \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-address <GAME_ADDRESS> \
  --claim <CLAIM_INDEX> \
  <SIGNER_ARGS>

Resolves a claim in a dispute game. Note that this will fail if the claim has already been resolved or if the claim is not yet resolvable. If the claim is resolved successfully, the result is printed.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_ADDRESS - the address of the dispute game to resolve.
• CLAIM_INDEX - the index of the claim to resolve.
• SIGNER_ARGS arguments to specify the key to sign transactions with (e.g --private-key).

resolve

./bin/op-challenger resolve \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-address <GAME_ADDRESS> \
  <SIGNER_ARGS>

Resolves a dispute game. Note that this will fail if the dispute game has already been resolved or if the clocks have not yet expired and further moves are possible. If the game is resolved successfully, the result is printed.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_ADDRESS - the address of the dispute game to resolve.
• SIGNER_ARGS arguments to specify the key to sign transactions with (e.g --private-key).

list-games

./bin/op-challenger list-games \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-factory-address <GAME_FACTORY_ADDRESS>

Prints the games created by the game factory along with their current status.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_FACTORY_ADDRESS - the address of the dispute game factory contract on L1.

list-claims

./bin/op-challenger list-claims \
  --l1-eth-rpc <L1_ETH_RPC> \
  --game-address <GAME_ADDRESS>

Prints the list of current claims in a dispute game.

• L1_ETH_RPC - the RPC endpoint of the L1 endpoint to use (e.g. http://localhost:8545).
• GAME_ADDRESS - the address of the dispute game to list the move in.