lighthouse/eth2/state_processing/src/genesis.rs
Michael Sproul 26bdc2927b
Update to spec v0.11 (#959)
* Update process_final_updates() hysteresis computation

* Update core to v0.11.1

* Bump tags to v0.11.1

* Update docs and deposit contract

* Add compute_fork_digest

* Address review comments

Co-authored-by: Herman Alonso Junge <alonso.junge@gmail.com>
2020-04-01 22:03:03 +11:00

76 lines
2.8 KiB
Rust

use super::per_block_processing::{errors::BlockProcessingError, process_deposit};
use crate::common::DepositDataTree;
use tree_hash::TreeHash;
use types::DEPOSIT_TREE_DEPTH;
use types::*;
/// Initialize a `BeaconState` from genesis data.
///
/// Spec v0.11.1
// TODO: this is quite inefficient and we probably want to rethink how we do this
pub fn initialize_beacon_state_from_eth1<T: EthSpec>(
eth1_block_hash: Hash256,
eth1_timestamp: u64,
deposits: Vec<Deposit>,
spec: &ChainSpec,
) -> Result<BeaconState<T>, BlockProcessingError> {
let genesis_time =
eth1_timestamp - eth1_timestamp % spec.min_genesis_delay + 2 * spec.min_genesis_delay;
let eth1_data = Eth1Data {
// Temporary deposit root
deposit_root: Hash256::zero(),
deposit_count: deposits.len() as u64,
block_hash: eth1_block_hash,
};
let mut state = BeaconState::new(genesis_time, eth1_data, spec);
// Seed RANDAO with Eth1 entropy
state.fill_randao_mixes_with(eth1_block_hash);
let mut deposit_tree = DepositDataTree::create(&[], 0, DEPOSIT_TREE_DEPTH);
for deposit in deposits.iter() {
deposit_tree
.push_leaf(deposit.data.tree_hash_root())
.map_err(BlockProcessingError::MerkleTreeError)?;
state.eth1_data.deposit_root = deposit_tree.root();
process_deposit(&mut state, &deposit, spec, true)?;
}
process_activations(&mut state, spec);
// Now that we have our validators, initialize the caches (including the committees)
state.build_all_caches(spec)?;
// Set genesis validators root for domain separation and chain versioning
state.genesis_validators_root = state.update_validators_tree_hash_cache()?;
Ok(state)
}
/// Determine whether a candidate genesis state is suitable for starting the chain.
///
/// Spec v0.11.1
pub fn is_valid_genesis_state<T: EthSpec>(state: &BeaconState<T>, spec: &ChainSpec) -> bool {
state.genesis_time >= spec.min_genesis_time
&& state.get_active_validator_indices(T::genesis_epoch()).len() as u64
>= spec.min_genesis_active_validator_count
}
/// Activate genesis validators, if their balance is acceptable.
///
/// Spec v0.11.1
pub fn process_activations<T: EthSpec>(state: &mut BeaconState<T>, spec: &ChainSpec) {
for (index, validator) in state.validators.iter_mut().enumerate() {
let balance = state.balances[index];
validator.effective_balance = std::cmp::min(
balance - balance % spec.effective_balance_increment,
spec.max_effective_balance,
);
if validator.effective_balance == spec.max_effective_balance {
validator.activation_eligibility_epoch = T::genesis_epoch();
validator.activation_epoch = T::genesis_epoch();
}
}
}