393 lines
13 KiB
Rust
393 lines
13 KiB
Rust
// Copyright 2015-2017 Parity Technologies (UK) Ltd.
|
|
// This file is part of Parity.
|
|
|
|
// Parity is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
|
|
// Parity is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
/// Validator set maintained in a contract, updated using `getValidators` method.
|
|
|
|
use std::sync::Weak;
|
|
use futures::Future;
|
|
use native_contracts::ValidatorSet as Provider;
|
|
|
|
use util::*;
|
|
use util::cache::MemoryLruCache;
|
|
|
|
use basic_types::LogBloom;
|
|
use client::{Client, BlockChainClient};
|
|
use engines::Call;
|
|
use header::Header;
|
|
use ids::BlockId;
|
|
use log_entry::LogEntry;
|
|
|
|
use super::ValidatorSet;
|
|
use super::simple_list::SimpleList;
|
|
|
|
const MEMOIZE_CAPACITY: usize = 500;
|
|
|
|
// TODO: ethabi should be able to generate this.
|
|
const EVENT_NAME: &'static [u8] = &*b"ValidatorsChanged(bytes32,uint256,address[])";
|
|
|
|
lazy_static! {
|
|
static ref EVENT_NAME_HASH: H256 = EVENT_NAME.sha3();
|
|
}
|
|
|
|
/// The validator contract should have the following interface:
|
|
pub struct ValidatorSafeContract {
|
|
pub address: Address,
|
|
validators: RwLock<MemoryLruCache<H256, SimpleList>>,
|
|
provider: Provider,
|
|
client: RwLock<Option<Weak<Client>>>, // TODO [keorn]: remove
|
|
}
|
|
|
|
fn encode_proof(nonce: U256, validators: &[Address]) -> Bytes {
|
|
use rlp::RlpStream;
|
|
|
|
let mut stream = RlpStream::new_list(2);
|
|
stream.append(&nonce).append_list(validators);
|
|
stream.drain().to_vec()
|
|
}
|
|
|
|
impl ValidatorSafeContract {
|
|
pub fn new(contract_address: Address) -> Self {
|
|
ValidatorSafeContract {
|
|
address: contract_address,
|
|
validators: RwLock::new(MemoryLruCache::new(MEMOIZE_CAPACITY)),
|
|
provider: Provider::new(contract_address),
|
|
client: RwLock::new(None),
|
|
}
|
|
}
|
|
|
|
/// Queries the state and gets the set of validators.
|
|
fn get_list(&self, caller: &Call) -> Option<SimpleList> {
|
|
match self.provider.get_validators(caller).wait() {
|
|
Ok(new) => {
|
|
debug!(target: "engine", "Set of validators obtained: {:?}", new);
|
|
Some(SimpleList::new(new))
|
|
},
|
|
Err(s) => {
|
|
debug!(target: "engine", "Set of validators could not be updated: {}", s);
|
|
None
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Queries for the current validator set transition nonce.
|
|
fn get_nonce(&self, caller: &Call) -> Option<::util::U256> {
|
|
match self.provider.transition_nonce(caller).wait() {
|
|
Ok(nonce) => Some(nonce),
|
|
Err(s) => {
|
|
debug!(target: "engine", "Unable to fetch transition nonce: {}", s);
|
|
None
|
|
}
|
|
}
|
|
}
|
|
|
|
// Whether the header matches the expected bloom.
|
|
//
|
|
// The expected log should have 3 topics:
|
|
// 1. ETHABI-encoded log name.
|
|
// 2. the block's parent hash.
|
|
// 3. the "nonce": n for the nth transition in history.
|
|
//
|
|
// We can only search for the first 2, since we don't have the third
|
|
// just yet.
|
|
//
|
|
// The parent hash is included to prevent
|
|
// malicious actors from brute forcing other logs that would
|
|
// produce the same bloom.
|
|
//
|
|
// The log data is an array of all new validator addresses.
|
|
fn expected_bloom(&self, header: &Header) -> LogBloom {
|
|
LogEntry {
|
|
address: self.address,
|
|
topics: vec![*EVENT_NAME_HASH, *header.parent_hash()],
|
|
data: Vec::new(), // irrelevant for bloom.
|
|
}.bloom()
|
|
}
|
|
}
|
|
|
|
impl ValidatorSet for ValidatorSafeContract {
|
|
fn default_caller(&self, id: BlockId) -> Box<Call> {
|
|
let client = self.client.read().clone();
|
|
Box::new(move |addr, data| client.as_ref()
|
|
.and_then(Weak::upgrade)
|
|
.ok_or("No client!".into())
|
|
.and_then(|c| c.call_contract(id, addr, data)))
|
|
}
|
|
|
|
fn is_epoch_end(&self, header: &Header, _block: Option<&[u8]>, receipts: Option<&[::receipt::Receipt]>)
|
|
-> ::engines::EpochChange
|
|
{
|
|
let bloom = self.expected_bloom(header);
|
|
let header_bloom = header.log_bloom();
|
|
|
|
if &bloom & header_bloom != bloom { return ::engines::EpochChange::No }
|
|
|
|
match receipts {
|
|
None => ::engines::EpochChange::Unsure(::engines::Unsure::NeedsReceipts),
|
|
Some(receipts) => {
|
|
let check_log = |log: &LogEntry| {
|
|
log.address == self.address &&
|
|
log.topics.len() == 3 &&
|
|
log.topics[0] == *EVENT_NAME_HASH &&
|
|
log.topics[1] == *header.parent_hash()
|
|
// don't have anything to compare nonce to yet.
|
|
};
|
|
|
|
let event = Provider::contract(&self.provider)
|
|
.event("ValidatorsChanged".into())
|
|
.expect("Contract known ahead of time to have `ValidatorsChanged` event; qed");
|
|
|
|
// iterate in reverse because only the _last_ change in a given
|
|
// block actually has any effect.
|
|
// the contract should only increment the nonce once.
|
|
let mut decoded_events = receipts.iter()
|
|
.rev()
|
|
.filter(|r| &bloom & &r.log_bloom == bloom)
|
|
.flat_map(|r| r.logs.iter())
|
|
.filter(move |l| check_log(l))
|
|
.filter_map(|log| {
|
|
let topics = log.topics.iter().map(|x| x.0.clone()).collect();
|
|
match event.decode_log(topics, log.data.clone()) {
|
|
Ok(decoded) => Some(decoded),
|
|
Err(_) => None,
|
|
}
|
|
});
|
|
|
|
match decoded_events.next() {
|
|
None => ::engines::EpochChange::No,
|
|
Some(matched_event) => {
|
|
// decode log manually until the native contract generator is
|
|
// good enough to do it for us.
|
|
let &(_, _, ref nonce_token) = &matched_event.params[1];
|
|
let &(_, _, ref validators_token) = &matched_event.params[2];
|
|
|
|
let nonce: Option<U256> = nonce_token.clone().to_uint()
|
|
.map(H256).map(Into::into);
|
|
let validators = validators_token.clone().to_array()
|
|
.and_then(|a| a.into_iter()
|
|
.map(|x| x.to_address().map(H160))
|
|
.collect::<Option<Vec<_>>>()
|
|
);
|
|
|
|
match (nonce, validators) {
|
|
(Some(nonce), Some(validators)) => {
|
|
let proof = encode_proof(nonce, &validators);
|
|
let new_epoch = nonce.low_u64();
|
|
::engines::EpochChange::Yes(new_epoch, proof)
|
|
}
|
|
_ => {
|
|
debug!(target: "engine", "Successfully decoded log turned out to be bad.");
|
|
::engines::EpochChange::No
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// the proof we generate is an RLP list containing two parts.
|
|
// (nonce, validators)
|
|
fn epoch_proof(&self, _header: &Header, caller: &Call) -> Result<Vec<u8>, String> {
|
|
match (self.get_nonce(caller), self.get_list(caller)) {
|
|
(Some(nonce), Some(list)) => Ok(encode_proof(nonce, &list.into_inner())),
|
|
_ => Err("Caller insufficient to generate validator proof.".into()),
|
|
}
|
|
}
|
|
|
|
fn epoch_set(&self, _header: &Header, proof: &[u8]) -> Result<(u64, SimpleList), ::error::Error> {
|
|
use rlp::UntrustedRlp;
|
|
|
|
let rlp = UntrustedRlp::new(proof);
|
|
let nonce: u64 = rlp.val_at(0)?;
|
|
let validators: Vec<Address> = rlp.list_at(1)?;
|
|
|
|
Ok((nonce, SimpleList::new(validators)))
|
|
}
|
|
|
|
fn contains_with_caller(&self, block_hash: &H256, address: &Address, caller: &Call) -> bool {
|
|
let mut guard = self.validators.write();
|
|
let maybe_existing = guard
|
|
.get_mut(block_hash)
|
|
.map(|list| list.contains(block_hash, address));
|
|
maybe_existing
|
|
.unwrap_or_else(|| self
|
|
.get_list(caller)
|
|
.map_or(false, |list| {
|
|
let contains = list.contains(block_hash, address);
|
|
guard.insert(block_hash.clone(), list);
|
|
contains
|
|
}))
|
|
}
|
|
|
|
fn get_with_caller(&self, block_hash: &H256, nonce: usize, caller: &Call) -> Address {
|
|
let mut guard = self.validators.write();
|
|
let maybe_existing = guard
|
|
.get_mut(block_hash)
|
|
.map(|list| list.get(block_hash, nonce));
|
|
maybe_existing
|
|
.unwrap_or_else(|| self
|
|
.get_list(caller)
|
|
.map_or_else(Default::default, |list| {
|
|
let address = list.get(block_hash, nonce);
|
|
guard.insert(block_hash.clone(), list);
|
|
address
|
|
}))
|
|
}
|
|
|
|
fn count_with_caller(&self, block_hash: &H256, caller: &Call) -> usize {
|
|
let mut guard = self.validators.write();
|
|
let maybe_existing = guard
|
|
.get_mut(block_hash)
|
|
.map(|list| list.count(block_hash));
|
|
maybe_existing
|
|
.unwrap_or_else(|| self
|
|
.get_list(caller)
|
|
.map_or_else(usize::max_value, |list| {
|
|
let address = list.count(block_hash);
|
|
guard.insert(block_hash.clone(), list);
|
|
address
|
|
}))
|
|
}
|
|
|
|
fn register_contract(&self, client: Weak<Client>) {
|
|
trace!(target: "engine", "Setting up contract caller.");
|
|
*self.client.write() = Some(client);
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use util::*;
|
|
use types::ids::BlockId;
|
|
use spec::Spec;
|
|
use account_provider::AccountProvider;
|
|
use transaction::{Transaction, Action};
|
|
use client::{BlockChainClient, EngineClient};
|
|
use ethkey::Secret;
|
|
use miner::MinerService;
|
|
use tests::helpers::{generate_dummy_client_with_spec_and_accounts, generate_dummy_client_with_spec_and_data};
|
|
use super::super::ValidatorSet;
|
|
use super::{ValidatorSafeContract, EVENT_NAME_HASH};
|
|
|
|
#[test]
|
|
fn fetches_validators() {
|
|
let client = generate_dummy_client_with_spec_and_accounts(Spec::new_validator_safe_contract, None);
|
|
let vc = Arc::new(ValidatorSafeContract::new(Address::from_str("0000000000000000000000000000000000000005").unwrap()));
|
|
vc.register_contract(Arc::downgrade(&client));
|
|
let last_hash = client.best_block_header().hash();
|
|
assert!(vc.contains(&last_hash, &Address::from_str("7d577a597b2742b498cb5cf0c26cdcd726d39e6e").unwrap()));
|
|
assert!(vc.contains(&last_hash, &Address::from_str("82a978b3f5962a5b0957d9ee9eef472ee55b42f1").unwrap()));
|
|
}
|
|
|
|
#[test]
|
|
fn knows_validators() {
|
|
let tap = Arc::new(AccountProvider::transient_provider());
|
|
let s0 = Secret::from_slice(&"1".sha3()).unwrap();
|
|
let v0 = tap.insert_account(s0.clone(), "").unwrap();
|
|
let v1 = tap.insert_account(Secret::from_slice(&"0".sha3()).unwrap(), "").unwrap();
|
|
let network_id = Spec::new_validator_safe_contract().network_id();
|
|
let client = generate_dummy_client_with_spec_and_accounts(Spec::new_validator_safe_contract, Some(tap));
|
|
client.engine().register_client(Arc::downgrade(&client));
|
|
let validator_contract = Address::from_str("0000000000000000000000000000000000000005").unwrap();
|
|
|
|
client.miner().set_engine_signer(v1, "".into()).unwrap();
|
|
// Remove "1" validator.
|
|
let tx = Transaction {
|
|
nonce: 0.into(),
|
|
gas_price: 0.into(),
|
|
gas: 500_000.into(),
|
|
action: Action::Call(validator_contract),
|
|
value: 0.into(),
|
|
data: "bfc708a000000000000000000000000082a978b3f5962a5b0957d9ee9eef472ee55b42f1".from_hex().unwrap(),
|
|
}.sign(&s0, Some(network_id));
|
|
client.miner().import_own_transaction(client.as_ref(), tx.into()).unwrap();
|
|
client.update_sealing();
|
|
assert_eq!(client.chain_info().best_block_number, 1);
|
|
// Add "1" validator back in.
|
|
let tx = Transaction {
|
|
nonce: 1.into(),
|
|
gas_price: 0.into(),
|
|
gas: 500_000.into(),
|
|
action: Action::Call(validator_contract),
|
|
value: 0.into(),
|
|
data: "4d238c8e00000000000000000000000082a978b3f5962a5b0957d9ee9eef472ee55b42f1".from_hex().unwrap(),
|
|
}.sign(&s0, Some(network_id));
|
|
client.miner().import_own_transaction(client.as_ref(), tx.into()).unwrap();
|
|
client.update_sealing();
|
|
// The transaction is not yet included so still unable to seal.
|
|
assert_eq!(client.chain_info().best_block_number, 1);
|
|
|
|
// Switch to the validator that is still there.
|
|
client.miner().set_engine_signer(v0, "".into()).unwrap();
|
|
client.update_sealing();
|
|
assert_eq!(client.chain_info().best_block_number, 2);
|
|
// Switch back to the added validator, since the state is updated.
|
|
client.miner().set_engine_signer(v1, "".into()).unwrap();
|
|
let tx = Transaction {
|
|
nonce: 2.into(),
|
|
gas_price: 0.into(),
|
|
gas: 21000.into(),
|
|
action: Action::Call(Address::default()),
|
|
value: 0.into(),
|
|
data: Vec::new(),
|
|
}.sign(&s0, Some(network_id));
|
|
client.miner().import_own_transaction(client.as_ref(), tx.into()).unwrap();
|
|
client.update_sealing();
|
|
// Able to seal again.
|
|
assert_eq!(client.chain_info().best_block_number, 3);
|
|
|
|
// Check syncing.
|
|
let sync_client = generate_dummy_client_with_spec_and_data(Spec::new_validator_safe_contract, 0, 0, &[]);
|
|
sync_client.engine().register_client(Arc::downgrade(&sync_client));
|
|
for i in 1..4 {
|
|
sync_client.import_block(client.block(BlockId::Number(i)).unwrap().into_inner()).unwrap();
|
|
}
|
|
sync_client.flush_queue();
|
|
assert_eq!(sync_client.chain_info().best_block_number, 3);
|
|
}
|
|
|
|
#[test]
|
|
fn detects_bloom() {
|
|
use header::Header;
|
|
use engines::{EpochChange, Unsure};
|
|
use log_entry::LogEntry;
|
|
|
|
let client = generate_dummy_client_with_spec_and_accounts(Spec::new_validator_safe_contract, None);
|
|
let engine = client.engine().clone();
|
|
let validator_contract = Address::from_str("0000000000000000000000000000000000000005").unwrap();
|
|
|
|
let last_hash = client.best_block_header().hash();
|
|
let mut new_header = Header::default();
|
|
new_header.set_parent_hash(last_hash);
|
|
|
|
// first, try without the parent hash.
|
|
let mut event = LogEntry {
|
|
address: validator_contract,
|
|
topics: vec![*EVENT_NAME_HASH],
|
|
data: Vec::new(),
|
|
};
|
|
|
|
new_header.set_log_bloom(event.bloom());
|
|
assert_eq!(engine.is_epoch_end(&new_header, None, None), EpochChange::No);
|
|
|
|
// with the last hash, it should need the receipts.
|
|
event.topics.push(last_hash);
|
|
new_header.set_log_bloom(event.bloom());
|
|
assert_eq!(engine.is_epoch_end(&new_header, None, None),
|
|
EpochChange::Unsure(Unsure::NeedsReceipts));
|
|
}
|
|
}
|