Replay OP Stack batcher authorization across a key rotation
A historical derivation tool that hardcodes today’s batcher address can reject valid old batches and accept an address too early. Batcher authorization follows the L1 SystemConfig history.
Start with the configuration at the block being traversed
Load the chain’s genesis rollup configuration or a verified earlier derived state. Process ConfigUpdate logs emitted by the correct SystemConfig contract in canonical L1 order. Decode the BATCHER update and retain its origin.
L1 block H: ConfigUpdate sets batcher B
L1 block H + 1: inspect candidate transaction from B
If a candidate in the next L1 block is signed by B, compare it with the updated configuration and the expected batch inbox. The sender match alone does not turn an arbitrary L1 transaction into batch data.
Replay through reorganizations
When L1 reorganizes across the rotation, discard changes from the removed branch and rebuild the configuration on the new one. Distinguish batcher identity from the unsafe-block signer: rotating one role need not change the other. specs.optimism.io OP Stack specification