[Beta] Backports (#7945)

* ECIP 1041 - Remove Difficulty Bomb (#7905)

Enable difficulty bomb defusion at block:
 - 5900000 on Ethereum Classic mainnet,
 - 2300000 on morden testnet.

Reference:
https://github.com/ethereumproject/ECIPs/blob/master/ECIPs/ECIP-1041.md

* spec: Validate required divisor fields are not 0 (#7933)

* Add validate_non_zero function

It's used to validate that a Spec's uint field used as a divisor is not zero.

* Add deserialize_with to gas_limit_bound_divisor

Prevents panics due to divide-by-zero on the gas_limit_bound_divisor
field.

* Add deserialize_with to difficulty_bound_divisor

Prevents panics due to divide-by-zero on the difficulty_bound_divisor
field.

* Add validate_optional_non_zero function

Used to validate Option<Uint> divisor fields.

* Use deserialize_with on optional divisor fields.

* Add #[serde(default)] attribute to divisor fields

When using `#[serde(deserialize_with)]`, `#[serde(default)]` must be specified so that missing
fields can be deserialized with the deserializer for `None`.

* Kovan WASM fork code (#7849)

* kovan fork code

* introduce ethcore level vm_factory and let it fail

* fix json tests

* wasmcosts as option

* review changes

* wasm costs in parser

* fix evm tests

* review fixes

* fix test

* remove redundant json field

ethcore/evm/src/factory.rs

@@ -33,7 +33,7 @@ impl Factory {
 	/// Create fresh instance of VM
 	/// Might choose implementation depending on supplied gas.
 	#[cfg(feature = "jit")]
-	pub fn create(&self, gas: U256) -> Box<Vm> {
+	pub fn create(&self, gas: &U256) -> Box<Vm> {
 		match self.evm {
 			VMType::Jit => {
 				Box::new(super::jit::JitEvm::default())
@@ -49,7 +49,7 @@ impl Factory {
 	/// Create fresh instance of VM
 	/// Might choose implementation depending on supplied gas.
 	#[cfg(not(feature = "jit"))]
-	pub fn create(&self, gas: U256) -> Box<Vm> {
+	pub fn create(&self, gas: &U256) -> Box<Vm> {
 		match self.evm {
 			VMType::Interpreter => if Self::can_fit_in_usize(gas) {
 				Box::new(super::interpreter::Interpreter::<usize>::new(self.evm_cache.clone()))
@@ -68,8 +68,8 @@ impl Factory {
 		}
 	}
 
-	fn can_fit_in_usize(gas: U256) -> bool {
-		gas == U256::from(gas.low_u64() as usize)
+	fn can_fit_in_usize(gas: &U256) -> bool {
+		gas == &U256::from(gas.low_u64() as usize)
 	}
 }
 
@@ -95,7 +95,7 @@ impl Default for Factory {
 
 #[test]
 fn test_create_vm() {
-	let _vm = Factory::default().create(U256::zero());
+	let _vm = Factory::default().create(&U256::zero());
 }
 
 /// Create tests by injecting different VM factories

ethcore/evm/src/interpreter/mod.rs

@@ -914,8 +914,13 @@ mod tests {
 	use rustc_hex::FromHex;
 	use vmtype::VMType;
 	use factory::Factory;
-	use vm::{ActionParams, ActionValue};
+	use vm::{Vm, ActionParams, ActionValue};
 	use vm::tests::{FakeExt, test_finalize};
+	use bigint::prelude::U256;
+
+	fn interpreter(gas: &U256) -> Box<Vm> {
+		Factory::new(VMType::Interpreter, 1).create(gas)
+	}
 
 	#[test]
 	fn should_not_fail_on_tracing_mem() {
@@ -932,7 +937,7 @@ mod tests {
 		ext.tracing = true;
 
 		let gas_left = {
-			let mut vm = Factory::new(VMType::Interpreter, 1).create(params.gas);
+			let mut vm = interpreter(&params.gas);
 			test_finalize(vm.exec(params, &mut ext)).unwrap()
 		};
 
@@ -954,7 +959,7 @@ mod tests {
 		ext.tracing = true;
 
 		let err = {
-			let mut vm = Factory::new(VMType::Interpreter, 1).create(params.gas);
+			let mut vm = interpreter(&params.gas);
 			test_finalize(vm.exec(params, &mut ext)).err().unwrap()
 		};
 

ethcore/evm/src/tests.rs

@@ -40,7 +40,7 @@ fn test_add(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -60,7 +60,7 @@ fn test_sha3(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -80,7 +80,7 @@ fn test_address(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -102,7 +102,7 @@ fn test_origin(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -124,7 +124,7 @@ fn test_sender(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -159,7 +159,7 @@ fn test_extcodecopy(factory: super::Factory) {
 	ext.codes.insert(sender, Arc::new(sender_code));
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -179,7 +179,7 @@ fn test_log_empty(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -211,7 +211,7 @@ fn test_log_sender(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -236,7 +236,7 @@ fn test_blockhash(factory: super::Factory) {
 	ext.blockhashes.insert(U256::zero(), blockhash.clone());
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -258,7 +258,7 @@ fn test_calldataload(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -279,7 +279,7 @@ fn test_author(factory: super::Factory) {
 	ext.info.author = author;
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -299,7 +299,7 @@ fn test_timestamp(factory: super::Factory) {
 	ext.info.timestamp = timestamp;
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -319,7 +319,7 @@ fn test_number(factory: super::Factory) {
 	ext.info.number = number;
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -339,7 +339,7 @@ fn test_difficulty(factory: super::Factory) {
 	ext.info.difficulty = difficulty;
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -359,7 +359,7 @@ fn test_gas_limit(factory: super::Factory) {
 	ext.info.gas_limit = gas_limit;
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -377,7 +377,7 @@ fn test_mul(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -395,7 +395,7 @@ fn test_sub(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -413,7 +413,7 @@ fn test_div(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -431,7 +431,7 @@ fn test_div_zero(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -449,7 +449,7 @@ fn test_mod(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -468,7 +468,7 @@ fn test_smod(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -487,7 +487,7 @@ fn test_sdiv(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -506,7 +506,7 @@ fn test_exp(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -526,7 +526,7 @@ fn test_comparison(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -547,7 +547,7 @@ fn test_signed_comparison(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -568,7 +568,7 @@ fn test_bitops(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -591,7 +591,7 @@ fn test_addmod_mulmod(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -612,7 +612,7 @@ fn test_byte(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -631,7 +631,7 @@ fn test_signextend(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -651,7 +651,7 @@ fn test_badinstruction_int() {
 	let mut ext = FakeExt::new();
 
 	let err = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap_err()
 	};
 
@@ -671,7 +671,7 @@ fn test_pop(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -691,7 +691,7 @@ fn test_extops(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -714,7 +714,7 @@ fn test_jumps(factory: super::Factory) {
 	let mut ext = FakeExt::new();
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -742,7 +742,7 @@ fn test_calls(factory: super::Factory) {
 	};
 
 	let gas_left = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap()
 	};
 
@@ -781,7 +781,7 @@ fn test_create_in_staticcall(factory: super::Factory) {
 	ext.is_static = true;
 
 	let err = {
-		let mut vm = factory.create(params.gas);
+		let mut vm = factory.create(&params.gas);
 		test_finalize(vm.exec(params, &mut ext)).unwrap_err()
 	};