Add randomness contract support to Authority Round.

Changes have been cherry-picked from poanetwork's aura-pos branch.
Most of the work has been done by @mbr.

ethcore/Cargo.toml

@@ -14,6 +14,7 @@ blooms-db = { path = "../util/blooms-db", optional = true }
 client-traits = { path = "./client-traits" }
 common-types = { path = "types" }
 crossbeam-utils = "0.6"
+derive_more = "0.15.0"
 engine = { path = "./engine" }
 env_logger = { version = "0.5", optional = true }
 ethabi = "8.0"

ethcore/client-traits/src/lib.rs

@@ -40,7 +40,7 @@ use common_types::{
 	pruning_info::PruningInfo,
 	receipt::LocalizedReceipt,
 	trace_filter::Filter as TraceFilter,
-	transaction::{self, LocalizedTransaction, CallError, SignedTransaction},
+	transaction::{self, Action, LocalizedTransaction, CallError, SignedTransaction},
 	tree_route::TreeRoute,
 	verification::{VerificationQueueInfo, Unverified},
 };
@@ -367,7 +367,27 @@ pub trait BlockChainClient : Sync + Send + AccountData + BlockChain + CallContra
 	fn pruning_info(&self) -> PruningInfo;
 
 	/// Schedule state-altering transaction to be executed on the next pending block.
-	fn transact_contract(&self, address: Address, data: Bytes) -> Result<(), transaction::Error>;
+	fn transact_contract(&self, address: Address, data: Bytes) -> Result<(), transaction::Error> {
+		self.transact(Action::Call(address), data, None, None, None)
+	}
+
+	/// Returns a signed transaction. If gas limit, gas price, or nonce are not
+	/// specified, the defaults are used.
+	fn create_transaction(
+		&self,
+		action: Action,
+		data: Bytes,
+		gas: Option<U256>,
+		gas_price: Option<U256>,
+		nonce: Option<U256>
+	) -> Result<SignedTransaction, transaction::Error>;
+
+	/// Schedule state-altering transaction to be executed on the next pending
+	/// block with the given gas and nonce parameters.
+	///
+	/// If they are `None`, sensible values are selected automatically.
+	fn transact(&self, action: Action, data: Bytes, gas: Option<U256>, gas_price: Option<U256>, nonce: Option<U256>)
+		-> Result<(), transaction::Error>;
 
 	/// Get the address of the registry itself.
 	fn registrar_address(&self) -> Option<Address>;

ethcore/engine/src/engine.rs

@@ -31,7 +31,7 @@ use common_types::{
 		machine::{AuxiliaryData, AuxiliaryRequest},
 	},
 	errors::{EthcoreError as Error, EngineError},
-	transaction::{self, UnverifiedTransaction},
+	transaction::{self, SignedTransaction, UnverifiedTransaction},
 };
 use client_traits::EngineClient;
 
@@ -187,6 +187,12 @@ pub trait Engine: Sync + Send {
 	/// Allow mutating the header during seal generation. Currently only used by Clique.
 	fn on_seal_block(&self, _block: &mut ExecutedBlock) -> Result<(), Error> { Ok(()) }
 
+	/// Returns a list of transactions for a new block if we are the author.
+	///
+	/// This is called when the miner prepares a new block that this node will author and seal. It returns a list of
+	/// transactions that will be added to the block before any other transactions from the queue.
+	fn on_prepare_block(&self, _block: &ExecutedBlock) -> Result<Vec<SignedTransaction>, Error> { Ok(Vec::new()) }
+
 	/// Returns the engine's current sealing state.
 	fn sealing_state(&self) -> SealingState { SealingState::External }
 

ethcore/engine/src/signer.rs

@@ -18,6 +18,7 @@
 
 use ethereum_types::{H256, Address};
 use ethkey::{self, Signature};
+use ethkey::crypto::ecies;
 
 /// Everything that an Engine needs to sign messages.
 pub trait EngineSigner: Send + Sync {
@@ -26,6 +27,12 @@ pub trait EngineSigner: Send + Sync {
 
 	/// Signing address
 	fn address(&self) -> Address;
+
+	/// Decrypt a message that was encrypted to this signer's key.
+	fn decrypt(&self, auth_data: &[u8], cipher: &[u8]) -> Result<Vec<u8>, ethkey::crypto::Error>;
+
+	/// The signer's public key, if available.
+	fn public(&self) -> Option<ethkey::Public>;
 }
 
 /// Creates a new `EngineSigner` from given key pair.
@@ -40,7 +47,15 @@ impl EngineSigner for Signer {
 		ethkey::sign(self.0.secret(), &hash)
 	}
 
+	fn decrypt(&self, auth_data: &[u8], cipher: &[u8]) -> Result<Vec<u8>, ethkey::crypto::Error> {
+		ecies::decrypt(self.0.secret(), auth_data, cipher)
+	}
+
 	fn address(&self) -> Address {
 		self.0.address()
 	}
+
+	fn public(&self) -> Option<ethkey::Public> {
+		Some(*self.0.public())
+	}
 }

ethcore/engine/src/test_helpers.rs

@@ -43,7 +43,18 @@ impl EngineSigner for (Arc<AccountProvider>, Address, Password) {
 		}
 	}
 
+	fn decrypt(&self, auth_data: &[u8], cipher: &[u8]) -> Result<Vec<u8>, ethkey::crypto::Error> {
+		self.0.decrypt(self.1, None, auth_data, cipher).map_err(|e| {
+			warn!("Unable to decrypt message: {:?}", e);
+			ethkey::crypto::Error::InvalidMessage
+		})
+	}
+
 	fn address(&self) -> Address {
 		self.1
 	}
+
+	fn public(&self) -> Option<ethkey::Public> {
+		self.0.account_public(self.1, &self.2).ok()
+	}
 }

ethcore/res/authority_round_randomness_contract.json

@@ -0,0 +1,60 @@
+{
+	"name": "TestAuthorityRoundRandomnessContract",
+	"engine": {
+		"authorityRound": {
+			"params": {
+				"stepDuration": 1,
+				"startStep": 2,
+				"validators": {
+					"list": [
+						"0x7d577a597b2742b498cb5cf0c26cdcd726d39e6e"
+					]
+				},
+				"immediateTransitions": true,
+				"maximumEmptySteps": "2",
+				"randomnessContractAddress": "0x0000000000000000000000000000000000000042"
+			}
+		}
+	},
+	"params": {
+		"gasLimitBoundDivisor": "0x0400",
+		"accountStartNonce": "0x0",
+		"maximumExtraDataSize": "0x20",
+		"minGasLimit": "0x1388",
+		"networkID" : "0x69",
+		"eip140Transition": "0x0",
+		"eip211Transition": "0x0",
+		"eip214Transition": "0x0",
+		"eip658Transition": "0x0"
+	},
+	"genesis": {
+		"seal": {
+			"authorityRound": {
+				"step": "0x0",
+				"signature": "0x0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
+			}
+		},
+		"difficulty": "0x20000",
+		"author": "0x0000000000000000000000000000000000000000",
+		"timestamp": "0x00",
+		"parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
+		"extraData": "0x",
+		"gasLimit": "0x222222"
+	},
+	"accounts": {
+		"0x7d577a597b2742b498cb5cf0c26cdcd726d39e6e": { "balance": "100000000000" },
+		"0000000000000000000000000000000000000001": { "balance": "1", "nonce": "1048576", "builtin": { "name": "ecrecover", "pricing": { "linear": { "base": 3000, "word": 0 } } } },
+		"0000000000000000000000000000000000000002": { "balance": "1", "nonce": "1048576", "builtin": { "name": "sha256", "pricing": { "linear": { "base": 60, "word": 12 } } } },
+		"0000000000000000000000000000000000000003": { "balance": "1", "nonce": "1048576", "builtin": { "name": "ripemd160", "pricing": { "linear": { "base": 600, "word": 120 } } } },
+		"0000000000000000000000000000000000000004": { "balance": "1", "nonce": "1048576", "builtin": { "name": "identity", "pricing": { "linear": { "base": 15, "word": 3 } } } },
+		"0000000000000000000000000000000000000005": { "balance": "1", "builtin": { "name": "modexp", "activate_at": 0, "pricing": { "modexp": { "divisor": 20 } } } },
+		"0000000000000000000000000000000000000006": { "balance": "1", "builtin": { "name": "alt_bn128_add", "activate_at": 0, "pricing": { "linear": { "base": 500, "word": 0 } } } },
+		"0000000000000000000000000000000000000007": { "balance": "1", "builtin": { "name": "alt_bn128_mul", "activate_at": 0, "pricing": { "linear": { "base": 40000, "word": 0 } } } },
+		"0000000000000000000000000000000000000008": { "balance": "1", "builtin": { "name": "alt_bn128_pairing", "activate_at": 0, "pricing": { "alt_bn128_pairing": { "base": 100000, "pair": 80000 } } } },
+		"9cce34f7ab185c7aba1b7c8140d620b4bda941d6": { "balance": "1606938044258990275541962092341162602522202993782792835301376", "nonce": "1048576" },
+		"0000000000000000000000000000000000000042": {
+			"balance": "1",
+			"constructor": "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"
+		}
+	}
+}

ethcore/res/contracts/authority_round_random.json

@@ -0,0 +1,158 @@
+[{
+		"constant": true,
+		"inputs": [],
+		"name": "currentRandom",
+		"outputs": [{
+			"name": "",
+			"type": "uint256[]"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": false,
+		"inputs": [{
+				"name": "_secretHash",
+				"type": "bytes32"
+			},
+			{
+				"name": "_cipher",
+				"type": "bytes"
+			}
+		],
+		"name": "commitHash",
+		"outputs": [],
+		"payable": false,
+		"stateMutability": "nonpayable",
+		"type": "function"
+	},
+	{
+		"constant": false,
+		"inputs": [{
+			"name": "_secret",
+			"type": "uint256"
+		}],
+		"name": "revealSecret",
+		"outputs": [],
+		"payable": false,
+		"stateMutability": "nonpayable",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [],
+		"name": "currentCollectRound",
+		"outputs": [{
+			"name": "",
+			"type": "uint256"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [{
+				"name": "_collectRound",
+				"type": "uint256"
+			},
+			{
+				"name": "_validator",
+				"type": "address"
+			}
+		],
+		"name": "getCipher",
+		"outputs": [{
+			"name": "",
+			"type": "bytes"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [{
+				"name": "_collectRound",
+				"type": "uint256"
+			},
+			{
+				"name": "_validator",
+				"type": "address"
+			}
+		],
+		"name": "getCommit",
+		"outputs": [{
+			"name": "",
+			"type": "bytes32"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [{
+				"name": "_collectRound",
+				"type": "uint256"
+			},
+			{
+				"name": "_validator",
+				"type": "address"
+			}
+		],
+		"name": "isCommitted",
+		"outputs": [{
+			"name": "",
+			"type": "bool"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [],
+		"name": "isCommitPhase",
+		"outputs": [{
+			"name": "",
+			"type": "bool"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [],
+		"name": "isRevealPhase",
+		"outputs": [{
+			"name": "",
+			"type": "bool"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	},
+	{
+		"constant": true,
+		"inputs": [{
+				"name": "_collectRound",
+				"type": "uint256"
+			},
+			{
+				"name": "_validator",
+				"type": "address"
+			}
+		],
+		"name": "sentReveal",
+		"outputs": [{
+			"name": "",
+			"type": "bool"
+		}],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	}
+]