openethereum/src/evm/executive.rs
2016-01-10 12:29:35 +01:00

458 lines
14 KiB
Rust

use std::collections::HashSet;
use std::cmp;
use util::hash::*;
use util::uint::*;
use util::rlp::*;
use util::sha3::*;
use util::bytes::*;
use state::*;
use env_info::*;
use engine::*;
use transaction::*;
use evm::{VmFactory, Ext, LogEntry, EvmParams, EvmResult};
/// Returns new address created from address and given nonce.
pub fn contract_address(address: &Address, nonce: &U256) -> Address {
let mut stream = RlpStream::new_list(2);
stream.append(address);
stream.append(nonce);
From::from(stream.out().sha3())
}
/// State changes which should be applied in finalize,
/// after transaction is fully executed.
pub struct Substate {
/// Any accounts that have suicided.
suicides: HashSet<Address>,
/// Any logs.
logs: Vec<LogEntry>,
/// Refund counter of SSTORE nonzero->zero.
refunds_count: U256,
}
impl Substate {
/// Creates new substate.
pub fn new() -> Self {
Substate {
suicides: HashSet::new(),
logs: vec![],
refunds_count: U256::zero(),
}
}
pub fn logs(&self) -> &[LogEntry] {
&self.logs
}
/// Appends another substate to this substate.
fn accrue(&mut self, s: Substate) {
self.suicides.extend(s.suicides.into_iter());
self.logs.extend(s.logs.into_iter());
self.refunds_count = self.refunds_count + s.refunds_count;
}
}
#[derive(PartialEq, Debug)]
pub enum ExecutiveResult {
Ok,
BlockGasLimitReached { gas_limit: U256, gas_used: U256, gas: U256 },
InvalidNonce { expected: U256, is: U256 },
NotEnoughCash { required: U256, is: U256 },
OutOfGas,
InternalError
}
/// Message-call/contract-creation executor; useful for executing transactions.
pub struct Executive<'a> {
state: &'a mut State,
info: &'a EnvInfo,
engine: &'a Engine,
depth: usize,
}
impl<'a> Executive<'a> {
/// Creates new executive with depth equal 0.
pub fn new(state: &'a mut State, info: &'a EnvInfo, engine: &'a Engine) -> Self {
Executive::new_with_depth(state, info, engine, 0)
}
/// Populates executive from parent externalities. Increments executive depth.
fn from_parent(e: &'a mut Externalities) -> Self {
Executive::new_with_depth(e.state, e.info, e.engine, e.depth + 1)
}
/// Helper constructor. Should be used to create `Executive` with desired depth.
/// Private.
fn new_with_depth(state: &'a mut State, info: &'a EnvInfo, engine: &'a Engine, depth: usize) -> Self {
Executive {
state: state,
info: info,
engine: engine,
depth: depth,
}
}
/// This funtion should be used to execute transaction.
pub fn transact(e: &mut Executive<'a>, t: &Transaction) -> ExecutiveResult {
// validate if transaction fits into given block
if e.info.gas_used + t.gas > e.info.gas_limit {
return ExecutiveResult::BlockGasLimitReached {
gas_limit: e.info.gas_limit,
gas_used: e.info.gas_used,
gas: t.gas
};
}
let sender = t.sender();
let nonce = e.state.nonce(&sender);
// validate transaction nonce
if t.nonce != nonce {
return ExecutiveResult::InvalidNonce { expected: nonce, is: t.nonce };
}
// TODO: we might need bigints here, or at least check overflows.
let balance = e.state.balance(&sender);
let gas_cost = t.gas * t.gas_price;
let total_cost = t.value + gas_cost;
// avoid unaffordable transactions
if balance < total_cost {
return ExecutiveResult::NotEnoughCash { required: total_cost, is: balance };
}
e.state.inc_nonce(&sender);
let mut substate = Substate::new();
let res = match t.kind() {
TransactionKind::ContractCreation => {
let params = EvmParams {
address: contract_address(&sender, &nonce),
sender: sender.clone(),
origin: sender.clone(),
gas: t.gas,
gas_price: t.gas_price,
value: t.value,
code: t.data.clone(),
data: vec![],
};
Executive::call(e, &params, &mut substate)
},
TransactionKind::MessageCall => {
let params = EvmParams {
address: t.to.clone().unwrap(),
sender: sender.clone(),
origin: sender.clone(),
gas: t.gas,
gas_price: t.gas_price,
value: t.value,
code: e.state.code(&t.to.clone().unwrap()).unwrap_or(vec![]),
data: t.data.clone(),
};
Executive::create(e, &params, &mut substate)
}
};
// finalize here!
e.finalize(substate, &sender, U256::zero(), U256::zero(), t.gas_price);
res
}
/// Calls contract function with given contract params.
/// *Note. It does not finalize the transaction (doesn't do refunds, nor suicides).
fn call(e: &mut Executive<'a>, params: &EvmParams, substate: &mut Substate) -> ExecutiveResult {
// at first, transfer value to destination
e.state.transfer_balance(&params.sender, &params.address, &params.value);
// if destination is builtin, try to execute it, or quickly return
if e.engine.is_builtin(&params.address) {
return match e.engine.cost_of_builtin(&params.address, &params.data) > params.gas {
true => ExecutiveResult::OutOfGas,
false => {
// TODO: substract gas for execution
let mut out = vec![];
e.engine.execute_builtin(&params.address, &params.data, &mut out);
ExecutiveResult::Ok
}
}
}
// otherwise do `normal` execution if destination is a contract
// TODO: is executing contract with no code different from not executing contract at all?
// if yes, there is a logic issue here. mk
if params.code.len() > 0 {
return match {
let mut ext = Externalities::new(e.state, e.info, e.engine, e.depth, params, substate);
let evm = VmFactory::create();
evm.exec(&params, &mut ext)
} {
EvmResult::Stop => ExecutiveResult::Ok,
EvmResult::Return(_) => ExecutiveResult::Ok,
EvmResult::Suicide => {
substate.suicides.insert(params.address.clone());
ExecutiveResult::Ok
},
EvmResult::OutOfGas => ExecutiveResult::OutOfGas,
_err => ExecutiveResult::InternalError
}
}
ExecutiveResult::Ok
}
/// Creates contract with given contract params.
/// *Note. It does not finalize the transaction (doesn't do refunds, nor suicides).
fn create(e: &mut Executive<'a>, params: &EvmParams, substate: &mut Substate) -> ExecutiveResult {
// at first create new contract
e.state.new_contract(&params.address);
// then transfer value to it
e.state.transfer_balance(&params.sender, &params.address, &params.value);
match {
let mut ext = Externalities::new(e.state, e.info, e.engine, e.depth, params, substate);
let evm = VmFactory::create();
evm.exec(&params, &mut ext)
} {
EvmResult::Stop => {
ExecutiveResult::Ok
},
EvmResult::Return(output) => {
e.state.init_code(&params.address, output);
ExecutiveResult::Ok
},
EvmResult::Suicide => {
substate.suicides.insert(params.address.clone());
ExecutiveResult::Ok
},
EvmResult::OutOfGas => ExecutiveResult::OutOfGas,
_err => ExecutiveResult::InternalError
}
}
/// Finalizes the transaction (does refunds and suicides).
fn finalize(&mut self, substate: Substate, sender: &Address, gas: U256, gas_left: U256, gas_price: U256) {
let schedule = self.engine.evm_schedule(self.info);
// refunds from SSTORE nonzero -> zero
let sstore_refunds = U256::from(schedule.sstore_refund_gas) * substate.refunds_count;
// refunds from contract suicides
let suicide_refunds = U256::from(schedule.suicide_refund_gas) * U256::from(substate.suicides.len());
// real ammount to refund
let refund = cmp::min(sstore_refunds + suicide_refunds, (gas - gas_left) / U256::from(2)) + gas_left;
let refund_value = refund * gas_price;
self.state.add_balance(sender, &refund_value);
// fees earned by author
let fees = (gas - refund) * gas_price;
let author = &self.info.author;
self.state.add_balance(author, &fees);
// perform suicides
for address in substate.suicides.iter() {
self.state.kill_account(address);
}
}
}
/// Implementation of evm Externalities.
pub struct Externalities<'a> {
state: &'a mut State,
info: &'a EnvInfo,
engine: &'a Engine,
depth: usize,
params: &'a EvmParams,
substate: &'a mut Substate
}
impl<'a> Externalities<'a> {
/// Basic `Externalities` constructor.
pub fn new(state: &'a mut State, info: &'a EnvInfo, engine: &'a Engine, depth: usize, params: &'a EvmParams, substate: &'a mut Substate) -> Self {
Externalities {
state: state,
info: info,
engine: engine,
depth: depth,
params: params,
substate: substate
}
}
}
impl<'a> Ext for Externalities<'a> {
fn sload(&self, key: &H256) -> H256 {
self.state.storage_at(&self.params.address, key)
}
fn sstore(&mut self, key: H256, value: H256) {
// if SSTORE nonzero -> zero, increment refund count
if value == H256::new() && self.state.storage_at(&self.params.address, &key) != H256::new() {
self.substate.refunds_count = self.substate.refunds_count + U256::one();
}
self.state.set_storage(&self.params.address, key, value)
}
fn balance(&self, address: &Address) -> U256 {
self.state.balance(address)
}
fn blockhash(&self, number: &U256) -> H256 {
match *number < self.info.number {
false => H256::from(&U256::zero()),
true => {
let index = self.info.number - *number - U256::one();
self.info.last_hashes[index.low_u32() as usize].clone()
}
}
}
fn create(&mut self, gas: u64, endowment: &U256, code: &[u8]) -> Option<(Address, u64)> {
match self.state.balance(&self.params.address) >= *endowment && self.depth < 1024 {
false => None,
true => {
let address = contract_address(&self.params.address, &self.state.nonce(&self.params.address));
let params = EvmParams {
address: address.clone(),
sender: self.params.address.clone(),
origin: self.params.origin.clone(),
gas: U256::from(gas),
gas_price: self.params.gas_price.clone(),
value: endowment.clone(),
code: code.to_vec(),
data: vec![],
};
let mut substate = Substate::new();
{
let mut ex = Executive::from_parent(self);
ex.state.inc_nonce(&address);
let res = Executive::create(&mut ex, &params, &mut substate);
println!("res: {:?}", res);
}
self.substate.accrue(substate);
Some((address, gas))
}
}
}
fn call(&mut self, gas: u64, call_gas: u64, receive_address: &Address, value: &U256, data: &[u8], code_address: &Address) -> Option<(Vec<u8>, u64)>{
// TODO: validation of the call
let params = EvmParams {
address: code_address.clone(),
sender: receive_address.clone(),
origin: self.params.origin.clone(),
gas: U256::from(call_gas), // TODO:
gas_price: self.params.gas_price.clone(),
value: value.clone(),
code: self.state.code(code_address).unwrap_or(vec![]),
data: data.to_vec(),
};
let mut substate = Substate::new();
{
let mut ex = Executive::from_parent(self);
Executive::call(&mut ex, &params, &mut substate);
unimplemented!();
}
}
fn extcode(&self, address: &Address) -> Vec<u8> {
self.state.code(address).unwrap_or(vec![])
}
fn log(&mut self, topics: Vec<H256>, data: Bytes) {
let address = self.params.address.clone();
self.substate.logs.push(LogEntry::new(address, topics, data));
}
}
#[cfg(test)]
mod tests {
use rustc_serialize::hex::FromHex;
use std::str::FromStr;
use util::hash::*;
use util::uint::*;
use evm::*;
use transaction::*;
use env_info::*;
use state::*;
use spec::*;
use engine::*;
use evm_schedule::*;
use super::contract_address;
struct TestEngine;
impl TestEngine {
fn new() -> Self {
TestEngine
}
}
impl Engine for TestEngine {
fn name(&self) -> &str { "TestEngine" }
fn spec(&self) -> &Spec { unimplemented!() }
fn evm_schedule(&self, _env_info: &EnvInfo) -> EvmSchedule { EvmSchedule::new_frontier() }
}
#[test]
fn test_contract_address() {
let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
let expected_address = Address::from_str("3f09c73a5ed19289fb9bdc72f1742566df146f56").unwrap();
assert_eq!(expected_address, contract_address(&address, &U256::from(88)));
}
#[test]
// TODO: replace params with transactions!
fn test_executive() {
let sender = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
let address = contract_address(&sender, &U256::zero());
let mut params = EvmParams::new();
params.address = address.clone();
params.sender = sender.clone();
params.gas = U256::from(0x174876e800u64);
params.code = "3331600055".from_hex().unwrap();
params.value = U256::from(0x7);
let mut state = State::new_temp();
state.add_balance(&sender, &U256::from(0x100u64));
let info = EnvInfo::new();
let engine = TestEngine::new();
let mut substate = Substate::new();
{
let mut ex = Executive::new(&mut state, &info, &engine);
assert_eq!(Executive::create(&mut ex, &params, &mut substate), ExecutiveResult::Ok);
}
assert_eq!(state.storage_at(&address, &H256::new()), H256::from(&U256::from(0xf9u64)));
assert_eq!(state.balance(&sender), U256::from(0xf9));
assert_eq!(state.balance(&address), U256::from(0x7));
}
#[test]
fn test_create_contract() {
let sender = Address::from_str("cd1722f3947def4cf144679da39c4c32bdc35681").unwrap();
let address = contract_address(&sender, &U256::zero());
let next_address = contract_address(&address, &U256::zero());
let mut params = EvmParams::new();
params.address = address.clone();
params.sender = sender.clone();
params.origin = sender.clone();
params.gas = U256::from(0x174876e800u64);
params.code = "7c601080600c6000396000f3006000355415600957005b60203560003555600052601d60036000f0600055".from_hex().unwrap();
let mut state = State::new_temp();
state.add_balance(&sender, &U256::from(0x100u64));
let info = EnvInfo::new();
let engine = TestEngine::new();
let mut substate = Substate::new();
{
let mut ex = Executive::new(&mut state, &info, &engine);
assert_eq!(Executive::create(&mut ex, &params, &mut substate), ExecutiveResult::Ok);
}
assert_eq!(state.storage_at(&address, &H256::new()), H256::from(next_address.clone()));
assert_eq!(state.code(&next_address).unwrap(), "6000355415600957005b602035600035".from_hex().unwrap());
}
}