EIP-1559 specs for Ethereum Remote Client

[onyb]

Background

EIP-1559 proposes a dynamic adjustment of block sizes in response to changes in demand for gas, thereby translating volatility in transaction fees to volatility in block space. Transactions must pay a BASEFEE, which is basically some sort of a moving average based on the current gas limit.

Technical background

EIP-1559 introduces three gas variables into the picture:

1. baseFeePerGas ➜ recorded in block headers and burnt. 🔥
2. maxPriorityFeePerGas ➜ aka miner tip. ⚒️
3. maxFeePerGas ➜ same as baseFeePerGas + maxPriorityFeePerGas; anything extra is refunded back to user.

These new gas variables must be encoded into a brand-new transaction type (EIP-2718), defined by the following RLP:

0x02 || rlp([chainId, nonce, maxPriorityFeePerGas, maxFeePerGas, gasLimit,
             destination, value, data, accessList, signatureYParity, signatureR, signatureS])

Note that the baseFeePerGas is implicit and not part of the transaction RLP.

Screens

Metamask UX before EIP-1559

Metamask UX after EIP-1559 ✨

User stories

1. As a user, I can sign EIP-2178 typed transactions, post the London upgrade.
2. As a user, I can sign transactions that use EIP-1559 gas variables, post the London upgrade.
3. As a user, I can switch back to legacy transactions and gas controls, under Settings.
4. As a user, I can optionally customize the max priority fee and max fee, if EIP-1559 is activated.
5. As a user, I can continue using EVM-compatible chains and networks not supporting EIP-1559.

High-level Tech specs

• Upgrade keyring controllers to work with @ethereumjs/tx (including Ledger and Trezor bridges).
• Support EIP-2718 Typed Transaction Envelope using @ethereumjs/tx.
• Implement new components for EIP-1559 fee controls (see Metamask screens for UX inspiration).
• Update existing components (ex, transaction detail, history, etc.) to display fees correctly.
• Update transaction parser to extract details from EIP-2718 transactions.
• Implement a background script to read block headers and extract the base fee per gas.
• Integrate with gas API providers or support eth_maxPriorityFeePerGas (geth only?).
• Implement a background script to track the miner tip to pay for slow/medium/fast confirmations.
• Update fee estimation for transactions (see tx-gas-utils controller).
• Conditionally support various EIPs (1559, 2718) based on the activated hardfork.
• Support EIP-1559 in speedup and cancel functionalities.
• Allow switching back to legacy gas and raw transaction format easily.

Additional resources

• 1559 Cheatsheet for Implementers.
• Issue tracking implementation in the new Brave Wallet: Support new gas functionality for EIP 1559 for new wallet #14709

[onyb]

Self-QA audit

❌ = known failures - fix ongoing.
?? = not tested yet

Smoke tests

• Wallet unlocks without crashing (wait at least 15 seconds).
• Able to switch networks from the main wallet dashboard, without crashing.
• Legacy Type-0 transactions continue to work on Ledger hardware wallet.
  • ⚠️ Redo test with the latest firmware/app.
  • ⚠️ Also test Ledger integration extensively (unlock, get receive address, send, etc).
• Legacy Type-0 transactions continue to work on Trezor hardware wallet.
  • ⚠️ We have upgraded to Trezor Connect v8, hence Trezor integration must be extensively tested (unlock, get receive address, send, etc).

Send ETH flow

• Clicking on "Send" button does not result in any provider errors (watch out for Varnish errors in the console).
• Able to switch networks from the "Send ETH" container.
• Should not display gas controls in the "Send ETH" container.
• Should display EIP-1559 gas fields in the transaction summary (estimated max priority fee, and max fee).
• Should open gas controls on clicking "EDIT" in the transaction summary page.
• Should allow choosing between slow/average/fast under Basic gas controls.
• Should allow customizing max priority fee, max fee, and gas limit, in Advanced gas controls.
• Should perform basic validation of gas fields in Advanced gas controls.
• Should broadcast the transaction on clicking "Confirm".

Activity

• Should display max fee per gas and max priority fee per gas (in GWEI), under transaction details (values may be approximated).
• Should display total gas fee (max fee per gas X gas limit), under the Activity Log.

Send ERC-20 flow

• Should work exactly the same as Send ETH.

Replace by Fee / Replace by Nonce

• Pending transaction previously submitted with very low max priority fee, can be be sped up with custom fees.
• "-32000 transaction underpriced" RPC error is thrown if max priority fee per gas is 0.
• Pending transaction can be cancelled by bumping the max priority fee by 1.1x.
• Pending cancel transaction can be sped up by bumping the max priority fee by 1.1x.
• Failed transaction can be resubmitted by customizing the max priority fee.

Swap

• Should be able to swap ETH-DAI using legacy gas pricing fields (type-0 transaction).
• Should be able to approve allowance limit for DAI, in DAI-ETH swap. This must use legacy gas fields (type-0 transaction).
• Should be able to swap DAI-ETH using legacy gas pricing fields (type-0 transaction).
• Should be able to customize legacy gas pricing fields while fetching swap quotes.
• Should be able to customize legacy gas pricing fields in transaction confirmation page.

Fee estimation

• Max priority fee (per gas) estimates, in the gas controls modal, are close to what's being currently being paid on the network.
• maxFeePerGas = baseFeePerGas + maxPriorityFeePerGas always holds true (check etherscan).
• Time estimates for slow/average/fast are realistic (not very accurate, so don't bother too much).

Dapp interactions

• Should be able to swap ETH-UNI on Uniswap, using legacy gas pricing fields (type-0 transaction).
• ?? Should be able to ..., using EIP-1559 gas pricing fields (type-2 transaction).

[srirambv]

Verification passed on

Brave	1.29.75 Chromium: 93.0.4577.58 (Official Build) (x86_64)
Revision	c4410ece044414ea42fa4ba328d08195e818a99c-refs/branch-heads/4577@{#1076}
OS	macOS Version 11.5.2 (Build 20G95)
Component	1.0.37 dev

Verified tests from #17160 (comment) & brave/ethereum-remote-client#268

Smoke tests

• Wallet unlocks without crashing (wait at least 15 seconds)
• Able to switch networks from the main wallet dashboard, without crashing
• Legacy Type-0 transactions continue to work on Ledger hardware wallet
  • Unlock
  • Send Tx
  • Swap Tx

Unlock	Account	Send	Swap

• Legacy Type-0 transactions continue to work on Trezor hardware wallet
  • Unlock
  • Send Tx
  • Swap Tx

Unlock	Account	Send	Swap

Send ETH flow

• Verified clicking on "Send" button does not result in any provider errors in console
• Verified able to switch networks from the "Send ETH" container
• Verified gas controls is not shown in the "Send ETH" container
• Verified EIP-1559 gas fields are shown in the transaction summary (estimated max priority fee, and max fee)
• Verified gas controls open on clicking "EDIT" in the transaction summary page
• Verified choosing between slow/average/fast is available under Basic gas controls
• Verified customizing max priority fee, max fee, and gas limit, is available in Advanced gas controls
• Verified basic validation of gas fields in Advanced gas controls
• Verified transaction is broadcasted on clicking "Confirm".

Activity

• Verified max fee per gas and max priority fee per gas in GWEI is displayed under transaction details
• Verified Total gas fee (Gas Used by Transaction X Max Fee Per Gas) is shown under Activity log
  

Send ERC-20 flow

• Verified Send ERC-20 token works as expected. Txhash
  

Replace by Fee / Replace by Nonce

• Verified pending transaction previously submitted with very low max priority fee, can be be sped up with custom fees.
• Verified "-32000 transaction underpriced" RPC error is thrown if max priority fee per gas is 0.
• Verified pending transaction can be cancelled by bumping the max priority fee by 1.1x.
• Verified pending cancel transaction can be sped up by bumping the max priority fee by 1.1x.
• Verified failed transaction can be resubmitted by customizing the max priority fee.

Swap

• Verified able to swap ETH-DAI using legacy gas pricing fields (type-0 transaction).
• Verified able to approve allowance limit for DAI, in DAI-ETH swap. This must use legacy gas fields (type-0 transaction).
• Verified able to swap DAI-ETH using legacy gas pricing fields (type-0 transaction).
• Verified able to customize legacy gas pricing fields while fetching swap quotes.
• Verified able to customize legacy gas pricing fields in transaction confirmation page

Fee estimation

• Verified Max priority fee (per gas) estimates, in the gas controls modal, are close to what's being currently being paid on the network.
• Verified maxFeePerGas = baseFeePerGas + maxPriorityFeePerGas always holds true
• Verified Time estimates for slow/average/fast are realistic

Dapp interactions

• Verified able to swap ETH-UNI on Uniswap, using legacy gas pricing fields type-0 transaction
  

• Encountered #17907 & #17936

---

Verification passed on

Brave	1.30.65 Chromium: 93.0.4577.63 (Official Build) beta (64-bit)
Revision	ff5c0da2ec0adeaed5550e6c7e98417dac77d98a-refs/branch-heads/4577@{#1135}
OS	Linux
Component	1.0.37 dev

Verified tests from #17160 (comment) & brave/ethereum-remote-client#268

Smoke tests

• Wallet unlocks without crashing (wait at least 15 seconds)
• Able to switch networks from the main wallet dashboard, without crashing
• Legacy Type-0 transactions continue to work on Trezor hardware wallet
  • Unlock
  • Send Tx
  • Swap Tx

Unlock	Account	Send	Swap

• Legacy Type-0 transactions can't be checked on Ledger due to limitations with connecting the H/w device on Linux

Send ETH flow

• Verified clicking on "Send" button does not result in any provider errors in console
• Verified able to switch networks from the "Send ETH" container
• Verified gas controls is not shown in the "Send ETH" container
• Verified EIP-1559 gas fields are shown in the transaction summary (estimated max priority fee, and max fee)
• Verified gas controls open on clicking "EDIT" in the transaction summary page
• Verified choosing between slow/average/fast is available under Basic gas controls
• Verified customizing max priority fee, max fee, and gas limit, is available in Advanced gas controls
• Verified basic validation of gas fields in Advanced gas controls
• Verified transaction is broadcasted on clicking "Confirm".

|
| | | |
-- | -- | -- | -- | -- | --

Activity

• Verified max fee per gas and max priority fee per gas in GWEI is displayed under transaction details
• Verified Total gas fee (Gas Used by Transaction X Max Fee Per Gas) is shown under Activity log
  

Send ERC-20 flow

• Verified Send ERC-20 token works as expected. Txhash
  

Replace by Fee / Replace by Nonce

• Verified pending transaction previously submitted with very low max priority fee, can be be sped up with custom fees.
• Verified "-32000 transaction underpriced" RPC error is thrown if max priority fee per gas is 0.
• Verified pending transaction can be cancelled by bumping the max priority fee by 1.1x.
• Verified pending cancel transaction can be sped up by bumping the max priority fee by 1.1x.
• Verified failed transaction can be resubmitted by customizing the max priority fee.
  
  

Swap

• Verified able to swap ETH-DAI using legacy gas pricing fields (type-0 transaction).
• Verified able to approve allowance limit for DAI, in DAI-ETH swap. This must use legacy gas fields (type-0 transaction).
• Verified able to swap DAI-ETH using legacy gas pricing fields (type-0 transaction).
• Verified able to customize legacy gas pricing fields while fetching swap quotes.
• Verified able to customize legacy gas pricing fields in transaction confirmation page

Fee estimation

• Verified Max priority fee (per gas) estimates, in the gas controls modal, are close to what's being currently being paid on the network.
• Verified maxFeePerGas = baseFeePerGas + maxPriorityFeePerGas always holds true
• Verified Time estimates for slow/average/fast are realistic

Dapp interactions

• Verified able to swap ETH-UNI on Uniswap, using legacy gas pricing fields (type-0 transaction)
  

---

Verification passed on

Brave	1.31.27 Chromium: 93.0.4577.63 (Official Build) nightly (64-bit)
Revision	ff5c0da2ec0adeaed5550e6c7e98417dac77d98a-refs/branch-heads/4577@{#1135}
OS	Windows 10 OS Version 2009 (Build 19043.1165)
Component	1.0.37. dev

Verified tests from #17160 (comment) & brave/ethereum-remote-client#268

Smoke tests

• Wallet unlocks without crashing (wait at least 15 seconds)
• Able to switch networks from the main wallet dashboard, without crashing
• Legacy Type-0 transactions continue to work on Trezor hardware wallet
  • Unlock
  • Send Tx
  • Swap Tx

Unlock	Account	Send	Swap

• Legacy Type-0 transactions continue to work on Ledger Nano hardware wallet
  • Unlock
  • Send Tx
  • Swap Tx

Unlock	Account	Send	Swap

Send ETH flow

• Verified clicking on "Send" button does not result in any provider errors in console
• Verified able to switch networks from the "Send ETH" container
• Verified gas controls is not shown in the "Send ETH" container
• Verified EIP-1559 gas fields are shown in the transaction summary (estimated max priority fee, and max fee)
• Verified gas controls open on clicking "EDIT" in the transaction summary page
• Verified choosing between slow/average/fast is available under Basic gas controls
• Verified customizing max priority fee, max fee, and gas limit, is available in Advanced gas controls
• Verified basic validation of gas fields in Advanced gas controls
• Verified transaction is broadcasted on clicking "Confirm".

Activity

• Verified max fee per gas and max priority fee per gas in GWEI is displayed under transaction details
• Verified Total gas fee (Gas Used by Transaction X Max Fee Per Gas) is shown under Activity log
  

Send ERC-20 flow

• Verified Send ERC-20 token works as expected. (Txhash)
  

Replace by Fee / Replace by Nonce

• Verified pending transaction previously submitted with very low max priority fee, can be be sped up with custom fees.
• Verified "-32000 transaction underpriced" RPC error is thrown if max priority fee per gas is 0.
• Verified pending transaction can be cancelled by bumping the max priority fee by 1.1x.
• Verified pending cancel transaction can be sped up by bumping the max priority fee by 1.1x.
• Verified failed transaction can be resubmitted by customizing the max priority fee.
  
  

Swap

• Verified able to swap ETH-DAI using legacy gas pricing fields (type-0 transaction).
• Verified able to approve allowance limit for DAI, in DAI-ETH swap. This must use legacy gas fields (type-0 transaction).
• Verified able to swap DAI-ETH using legacy gas pricing fields (type-0 transaction).
• Verified able to customize legacy gas pricing fields while fetching swap quotes.
• Verified able to customize legacy gas pricing fields in transaction confirmation page

Fee estimation

• Verified Max priority fee (per gas) estimates, in the gas controls modal, are close to what's being currently being paid on the network.
• Verified maxFeePerGas = baseFeePerGas + maxPriorityFeePerGas always holds true
• Verified Time estimates for slow/average/fast are realistic

Dapp interactions

• Verified able to swap ETH-UNI on Uniswap, using legacy gas pricing fields (type-0 transaction)