openethereum/ethcore/src/spec.rs
2016-02-05 14:06:10 +01:00

323 lines
12 KiB
Rust

// Copyright 2015, 2016 Ethcore (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/>.
//! Parameters for a block chain.
use common::*;
use engine::*;
use pod_state::*;
use null_engine::*;
use account_db::*;
/// Convert JSON value to equivalent RLP representation.
// TODO: handle container types.
fn json_to_rlp(json: &Json) -> Bytes {
match *json {
Json::Boolean(o) => encode(&(if o {1u64} else {0})).to_vec(),
Json::I64(o) => encode(&(o as u64)).to_vec(),
Json::U64(o) => encode(&o).to_vec(),
Json::String(ref s) if s.len() >= 2 && &s[0..2] == "0x" && U256::from_str(&s[2..]).is_ok() => {
encode(&U256::from_str(&s[2..]).unwrap()).to_vec()
},
Json::String(ref s) => {
encode(s).to_vec()
},
_ => panic!()
}
}
/// Convert JSON to a string->RLP map.
fn json_to_rlp_map(json: &Json) -> HashMap<String, Bytes> {
json.as_object().unwrap().iter().map(|(k, v)| (k, json_to_rlp(v))).fold(HashMap::new(), |mut acc, kv| {
acc.insert(kv.0.clone(), kv.1);
acc
})
}
/// Parameters for a block chain; includes both those intrinsic to the design of the
/// chain and those to be interpreted by the active chain engine.
#[derive(Debug)]
pub struct Spec {
/// User friendly spec name
pub name: String,
/// What engine are we using for this?
pub engine_name: String,
/// Known nodes on the network in enode format.
pub nodes: Vec<String>,
/// Parameters concerning operation of the specific engine we're using.
/// Maps the parameter name to an RLP-encoded value.
pub engine_params: HashMap<String, Bytes>,
/// Builtin-contracts we would like to see in the chain.
/// (In principle these are just hints for the engine since that has the last word on them.)
pub builtins: BTreeMap<Address, Builtin>,
/// The genesis block's parent hash field.
pub parent_hash: H256,
/// The genesis block's author field.
pub author: Address,
/// The genesis block's difficulty field.
pub difficulty: U256,
/// The genesis block's gas limit field.
pub gas_limit: U256,
/// The genesis block's gas used field.
pub gas_used: U256,
/// The genesis block's timestamp field.
pub timestamp: u64,
/// Transactions root of the genesis block. Should be SHA3_NULL_RLP.
pub transactions_root: H256,
/// Receipts root of the genesis block. Should be SHA3_NULL_RLP.
pub receipts_root: H256,
/// The genesis block's extra data field.
pub extra_data: Bytes,
/// The number of seal fields in the genesis block.
pub seal_fields: usize,
/// Each seal field, expressed as RLP, concatenated.
pub seal_rlp: Bytes,
// May be prepopulated if we know this in advance.
state_root_memo: RwLock<Option<H256>>,
// Genesis state as plain old data.
genesis_state: PodState,
}
#[allow(wrong_self_convention)] // because to_engine(self) should be to_engine(&self)
impl Spec {
/// Convert this object into a boxed Engine of the right underlying type.
// TODO avoid this hard-coded nastiness - use dynamic-linked plugin framework instead.
pub fn to_engine(self) -> Result<Box<Engine>, Error> {
match self.engine_name.as_ref() {
"NullEngine" => Ok(NullEngine::new_boxed(self)),
"Ethash" => Ok(super::ethereum::Ethash::new_boxed(self)),
_ => Err(Error::UnknownEngineName(self.engine_name.clone()))
}
}
/// Return the state root for the genesis state, memoising accordingly.
pub fn state_root(&self) -> H256 {
if self.state_root_memo.read().unwrap().is_none() {
*self.state_root_memo.write().unwrap() = Some(self.genesis_state.root());
}
self.state_root_memo.read().unwrap().as_ref().unwrap().clone()
}
/// Get the known knodes of the network in enode format.
pub fn nodes(&self) -> &Vec<String> { &self.nodes }
/// Get the header of the genesis block.
pub fn genesis_header(&self) -> Header {
Header {
parent_hash: self.parent_hash.clone(),
timestamp: self.timestamp,
number: 0,
author: self.author.clone(),
transactions_root: self.transactions_root.clone(),
uncles_hash: RlpStream::new_list(0).out().sha3(),
extra_data: self.extra_data.clone(),
state_root: self.state_root().clone(),
receipts_root: self.receipts_root.clone(),
log_bloom: H2048::new().clone(),
gas_used: self.gas_used.clone(),
gas_limit: self.gas_limit.clone(),
difficulty: self.difficulty.clone(),
seal: {
let seal = {
let mut s = RlpStream::new_list(self.seal_fields);
s.append_raw(&self.seal_rlp, self.seal_fields);
s.out()
};
let r = Rlp::new(&seal);
(0..self.seal_fields).map(|i| r.at(i).as_raw().to_vec()).collect()
},
hash: RefCell::new(None),
bare_hash: RefCell::new(None),
}
}
/// Compose the genesis block for this chain.
pub fn genesis_block(&self) -> Bytes {
let empty_list = RlpStream::new_list(0).out();
let header = self.genesis_header();
let mut ret = RlpStream::new_list(3);
ret.append(&header);
ret.append_raw(&empty_list, 1);
ret.append_raw(&empty_list, 1);
ret.out()
}
/// Overwrite the genesis components with the given JSON, assuming standard Ethereum test format.
pub fn overwrite_genesis(&mut self, genesis: &Json) {
let (seal_fields, seal_rlp) = {
if genesis.find("mixHash").is_some() && genesis.find("nonce").is_some() {
let mut s = RlpStream::new();
s.append(&H256::from_json(&genesis["mixHash"]));
s.append(&H64::from_json(&genesis["nonce"]));
(2, s.out())
} else {
// backup algo that will work with sealFields/sealRlp (and without).
(
u64::from_json(&genesis["sealFields"]) as usize,
Bytes::from_json(&genesis["sealRlp"])
)
}
};
self.parent_hash = H256::from_json(&genesis["parentHash"]);
self.transactions_root = genesis.find("transactionsTrie").and_then(|_| Some(H256::from_json(&genesis["transactionsTrie"]))).unwrap_or(SHA3_NULL_RLP.clone());
self.receipts_root = genesis.find("receiptTrie").and_then(|_| Some(H256::from_json(&genesis["receiptTrie"]))).unwrap_or(SHA3_NULL_RLP.clone());
self.author = Address::from_json(&genesis["coinbase"]);
self.difficulty = U256::from_json(&genesis["difficulty"]);
self.gas_limit = U256::from_json(&genesis["gasLimit"]);
self.gas_used = U256::from_json(&genesis["gasUsed"]);
self.timestamp = u64::from_json(&genesis["timestamp"]);
self.extra_data = Bytes::from_json(&genesis["extraData"]);
self.seal_fields = seal_fields;
self.seal_rlp = seal_rlp;
self.state_root_memo = RwLock::new(genesis.find("stateRoot").and_then(|_| Some(H256::from_json(&genesis["stateRoot"]))));
}
/// Alter the value of the genesis state.
pub fn set_genesis_state(&mut self, s: PodState) {
self.genesis_state = s;
*self.state_root_memo.write().unwrap() = None;
}
/// Returns `false` if the memoized state root is invalid. `true` otherwise.
pub fn is_state_root_valid(&self) -> bool {
self.state_root_memo.read().unwrap().clone().map_or(true, |sr| sr == self.genesis_state.root())
}
}
impl FromJson for Spec {
/// Loads a chain-specification from a json data structure
fn from_json(json: &Json) -> Spec {
// once we commit ourselves to some json parsing library (serde?)
// move it to proper data structure
let mut builtins = BTreeMap::new();
let mut state = PodState::new();
if let Some(&Json::Object(ref accounts)) = json.find("accounts") {
for (address, acc) in accounts.iter() {
let addr = Address::from_str(address).unwrap();
if let Some(ref builtin_json) = acc.find("builtin") {
if let Some(builtin) = Builtin::from_json(builtin_json) {
builtins.insert(addr.clone(), builtin);
}
}
}
state = xjson!(&json["accounts"]);
}
let nodes = if let Some(&Json::Array(ref ns)) = json.find("nodes") {
ns.iter().filter_map(|n| if let Json::String(ref s) = *n { Some(s.clone()) } else {None}).collect()
} else { Vec::new() };
let genesis = &json["genesis"];//.as_object().expect("No genesis object in JSON");
let (seal_fields, seal_rlp) = {
if genesis.find("mixHash").is_some() && genesis.find("nonce").is_some() {
let mut s = RlpStream::new();
s.append(&H256::from_str(&genesis["mixHash"].as_string().expect("mixHash not a string.")[2..]).expect("Invalid mixHash string value"));
s.append(&H64::from_str(&genesis["nonce"].as_string().expect("nonce not a string.")[2..]).expect("Invalid nonce string value"));
(2, s.out())
} else {
// backup algo that will work with sealFields/sealRlp (and without).
(
usize::from_str(&genesis["sealFields"].as_string().unwrap_or("0x")[2..]).expect("Invalid sealFields integer data"),
genesis["sealRlp"].as_string().unwrap_or("0x")[2..].from_hex().expect("Invalid sealRlp hex data")
)
}
};
Spec {
name: json.find("name").map_or("unknown", |j| j.as_string().unwrap()).to_owned(),
engine_name: json["engineName"].as_string().unwrap().to_owned(),
engine_params: json_to_rlp_map(&json["params"]),
nodes: nodes,
builtins: builtins,
parent_hash: H256::from_str(&genesis["parentHash"].as_string().unwrap()[2..]).unwrap(),
author: Address::from_str(&genesis["author"].as_string().unwrap()[2..]).unwrap(),
difficulty: U256::from_str(&genesis["difficulty"].as_string().unwrap()[2..]).unwrap(),
gas_limit: U256::from_str(&genesis["gasLimit"].as_string().unwrap()[2..]).unwrap(),
gas_used: U256::from(0u8),
timestamp: u64::from_str(&genesis["timestamp"].as_string().unwrap()[2..]).unwrap(),
transactions_root: SHA3_NULL_RLP.clone(),
receipts_root: SHA3_NULL_RLP.clone(),
extra_data: genesis["extraData"].as_string().unwrap()[2..].from_hex().unwrap(),
genesis_state: state,
seal_fields: seal_fields,
seal_rlp: seal_rlp,
state_root_memo: RwLock::new(genesis.find("stateRoot").and_then(|_| genesis["stateRoot"].as_string()).map(|s| H256::from_str(&s[2..]).unwrap())),
}
}
}
impl Spec {
/// Ensure that the given state DB has the trie nodes in for the genesis state.
pub fn ensure_db_good(&self, db: &mut HashDB) -> bool {
if !db.contains(&self.state_root()) {
let mut root = H256::new();
{
let mut t = SecTrieDBMut::new(db, &mut root);
for (address, account) in self.genesis_state.get().iter() {
t.insert(address.as_slice(), &account.rlp());
}
}
for (address, account) in self.genesis_state.get().iter() {
account.insert_additional(&mut AccountDBMut::new(db, address));
}
assert!(db.contains(&self.state_root()));
true
} else { false }
}
/// Create a new Spec from a JSON UTF-8 data resource `data`.
pub fn from_json_utf8(data: &[u8]) -> Spec {
Self::from_json_str(::std::str::from_utf8(data).unwrap())
}
/// Create a new Spec from a JSON string.
pub fn from_json_str(s: &str) -> Spec {
Self::from_json(&Json::from_str(s).expect("Json is invalid"))
}
/// Create a new Spec which conforms to the Morden chain except that it's a NullEngine consensus.
pub fn new_test() -> Spec { Self::from_json_utf8(include_bytes!("../res/null_morden.json")) }
}
#[cfg(test)]
mod tests {
use std::str::FromStr;
use util::hash::*;
use util::sha3::*;
use views::*;
use super::*;
#[test]
fn test_chain() {
let test_spec = Spec::new_test();
assert_eq!(test_spec.state_root(), H256::from_str("f3f4696bbf3b3b07775128eb7a3763279a394e382130f27c21e70233e04946a9").unwrap());
let genesis = test_spec.genesis_block();
assert_eq!(BlockView::new(&genesis).header_view().sha3(), H256::from_str("0cd786a2425d16f152c658316c423e6ce1181e15c3295826d7c9904cba9ce303").unwrap());
let _ = test_spec.to_engine();
}
}