feat: add frontier evm

[gregdhill]

Closes #1098

TODO

• Verify all parameters make sense (most are taken from Centrifuge or Moonbeam)
• Review signing logic (for wallet compatibility) and account conversion
• Confirm required precompiles (included standard Ethereum ones)
• Cleanup service (de-duplicate code, add SQL DB support, resolve TransactionConverter)
• Configurable contract creation
• Add EVM contract fixtures

Adds the following pallets to the interlay and kintsugi runtimes in addition to those required for RPC compatibility.

BaseFee (pallet_base_fee)

Controls the price per gas unit, updates based on the weight of the previous block - decreases if below or increases if above the target.

Ethereum (pallet_ethereum)

Emulation for block processing, validates and stores (EVM) transactions then constructs the Ethereum compatible block on_finalize.

EVM (pallet_evm)

Contains the SputnikVM to execute EVM bytecode compatible with the Ethereum mainnet.

Configuration

• Account version uses HashedAddressMapping

All non-root calls are disabled.

EVMChainId (pallet_evm_chain_id)

Stores the chain ID which is used by the EVM runner.

[gregdhill]

How the block / tx processing logic works:

1. User submits ethereum transaction over RPC https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/client/rpc-core/src/eth.rs#L240-L247
2. Runtime overrides extrinsic types https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/template/runtime/src/lib.rs#L468-L473 (adds additional signature and validity checks https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/primitives/self-contained/src/checked_extrinsic.rs#L36)
3. On execution it will append that transaction, status and execution receipt to Pending https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/frame/ethereum/src/lib.rs#L673
4. When the current Substrate block is built on_finalize it will include those transactions in an ethereum block https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/frame/ethereum/src/lib.rs#L442
5. That block can be fetched over RPC using the Runtime API https://github.com/paritytech/frontier/blob/bd5bd374fd50eb30eb381148243c46d882e057d5/template/runtime/src/lib.rs#L828C21-L828C33

[sander2]

Looks ok to me, but honestly it's very difficult to review, because there's so much code involved..

One question I do have is, how can the evm interact with our runtime? E.g. if it wants to check a bitcoin inclusion?

[sander2]

do we need to benchmark this somehow?

[gregdhill]

I'm actually not sure, but this is where Moonbeam defines it: https://github.com/moonbeam-foundation/moonbeam/blob/c55870bdda5bd40e97daffc27a5e3e1c037c5da9/runtime/moonbeam/src/lib.rs#L365-L369

[gregdhill]

AFAIK that is used in production and Centrifuge also copied that for their runtime.

[gregdhill]

The "flipper" contract fixture costs 133751 gas to create which would total (133751 * (10**10 / 100)) / 10**10 = 1337.51 INTR ($19.7).

[gregdhill]

The "flipper" contract fixture costs 133751 gas to create which would total (133751 * (10**12 / 30_000 * 10)) / 10**12 = 44.58 KINT ($16.94).

[gregdhill]

how can the evm interact with our runtime?

We need to add precompiles, see for example Acala's MultiCurrencyPrecompile.