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Merge branch 'master' into fo-6418-dont-export-bigint

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# Conflicts:
#	dapps/src/tests/helpers/registrar.rs
#	ethcore/evm/src/interpreter/shared_cache.rs
#	ethcore/light/src/client/header_chain.rs
#	ethcore/light/src/client/mod.rs
#	ethcore/light/src/net/mod.rs
#	ethcore/light/src/on_demand/request.rs
#	ethcore/light/src/on_demand/tests.rs
#	ethcore/light/src/provider.rs
#	ethcore/node_filter/src/lib.rs
#	ethcore/src/block.rs
#	ethcore/src/blockchain/blockchain.rs
#	ethcore/src/client/test_client.rs
#	ethcore/src/engines/authority_round/mod.rs
#	ethcore/src/engines/basic_authority.rs
#	ethcore/src/engines/mod.rs
#	ethcore/src/engines/tendermint/mod.rs
#	ethcore/src/engines/validator_set/contract.rs
#	ethcore/src/engines/validator_set/multi.rs
#	ethcore/src/engines/validator_set/safe_contract.rs
#	ethcore/src/engines/vote_collector.rs
#	ethcore/src/miner/external.rs
#	ethcore/src/miner/miner.rs
#	ethcore/src/miner/service_transaction_checker.rs
#	ethcore/src/miner/work_notify.rs
#	ethcore/src/pod_account.rs
#	ethcore/src/pod_state.rs
#	ethcore/src/snapshot/block.rs
#	ethcore/src/snapshot/consensus/work.rs
#	ethcore/src/snapshot/mod.rs
#	ethcore/src/snapshot/service.rs
#	ethcore/src/spec/spec.rs
#	ethcore/src/state/backend.rs
#	ethcore/src/trace/db.rs
#	ethcore/src/verification/queue/mod.rs
#	ethcore/src/verification/verification.rs
#	parity/informant.rs
#	rpc/src/v1/helpers/dispatch.rs
#	rpc/src/v1/helpers/light_fetch.rs
#	rpc/src/v1/helpers/signing_queue.rs
#	rpc/src/v1/impls/eth.rs
#	rpc/src/v1/impls/eth_filter.rs
#	rpc/src/v1/impls/eth_pubsub.rs
#	rpc/src/v1/impls/light/eth.rs
#	rpc/src/v1/impls/signing.rs
#	rpc/src/v1/tests/helpers/miner_service.rs
#	rpc/src/v1/tests/helpers/snapshot_service.rs
#	rpc/src/v1/tests/helpers/sync_provider.rs
#	rpc/src/v1/tests/mocked/eth.rs
#	stratum/src/lib.rs
#	sync/src/blocks.rs
#	sync/src/chain.rs
#	sync/src/light_sync/mod.rs
#	sync/src/tests/helpers.rs
#	sync/src/tests/snapshot.rs
#	updater/src/updater.rs
#	util/src/lib.rs
#	util/triehash/src/lib.rs
This commit is contained in:
Fredrik
2017-09-04 18:32:55 +02:00
parent 308f36a532 b731ccea18
commit e54784bfeb
127 changed files with 375 additions and 260 deletions
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92
ethcore/src/builtin.rs
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@@ -269,6 +269,34 @@ impl Impl for Ripemd160 {
}
}
// calculate modexp: exponentiation by squaring. the `num` crate has pow, but not modular.
fn modexp(mut base: BigUint, mut exp: BigUint, modulus: BigUint) -> BigUint {
use num::Integer;
match (base.is_zero(), exp.is_zero()) {
(_, true) => return BigUint::one(), // n^0 % m
(true, false) => return BigUint::zero(), // 0^n % m, n>0
(false, false) if modulus <= BigUint::one() => return BigUint::zero(), // a^b % 1 = 0.
_ => {}
}
let mut result = BigUint::one();
base = base % &modulus;
// fast path for base divisible by modulus.
if base.is_zero() { return BigUint::zero() }
while !exp.is_zero() {
if exp.is_odd() {
result = (result * &base) % &modulus;
}
exp = exp >> 1;
base = (base.clone() * base) % &modulus;
}
result
}
impl Impl for ModexpImpl {
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
let mut reader = input.chain(io::repeat(0));
@@ -297,34 +325,6 @@ impl Impl for ModexpImpl {
let exp = read_num(exp_len);
let modulus = read_num(mod_len);
// calculate modexp: exponentiation by squaring. the `num` crate has pow, but not modular.
fn modexp(mut base: BigUint, mut exp: BigUint, modulus: BigUint) -> BigUint {
use num::Integer;
match (base.is_zero(), exp.is_zero()) {
(_, true) => return BigUint::one(), // n^0 % m
(true, false) => return BigUint::zero(), // 0^n % m, n>0
(false, false) if modulus <= BigUint::one() => return BigUint::zero(), // a^b % 1 = 0.
_ => {}
}
let mut result = BigUint::one();
base = base % &modulus;
// fast path for base divisible by modulus.
if base.is_zero() { return result }
while !exp.is_zero() {
if exp.is_odd() {
result = (result * &base) % &modulus;
}
exp = exp >> 1;
base = (base.clone() * base) % &modulus;
}
result
}
// write output to given memory, left padded and same length as the modulus.
let bytes = modexp(base, exp, modulus).to_bytes_be();
@@ -506,11 +506,45 @@ impl Impl for Bn128PairingImpl {
#[cfg(test)]
mod tests {
use super::{Builtin, Linear, ethereum_builtin, Pricer, Modexp};
use super::{Builtin, Linear, ethereum_builtin, Pricer, Modexp, modexp as me};
use ethjson;
use bigint::prelude::U256;
use util::BytesRef;
use rustc_hex::FromHex;
use num::{BigUint, Zero, One};
#[test]
fn modexp_func() {
// n^0 % m == 1
let mut base = BigUint::parse_bytes(b"12345", 10).unwrap();
let mut exp = BigUint::zero();
let mut modulus = BigUint::parse_bytes(b"789", 10).unwrap();
assert_eq!(me(base, exp, modulus), BigUint::one());
// 0^n % m == 0
base = BigUint::zero();
exp = BigUint::parse_bytes(b"12345", 10).unwrap();
modulus = BigUint::parse_bytes(b"789", 10).unwrap();
assert_eq!(me(base, exp, modulus), BigUint::zero());
// n^m % 1 == 0
base = BigUint::parse_bytes(b"12345", 10).unwrap();
exp = BigUint::parse_bytes(b"789", 10).unwrap();
modulus = BigUint::one();
assert_eq!(me(base, exp, modulus), BigUint::zero());
// if n % d == 0, then n^m % d == 0
base = BigUint::parse_bytes(b"12345", 10).unwrap();
exp = BigUint::parse_bytes(b"789", 10).unwrap();
modulus = BigUint::parse_bytes(b"15", 10).unwrap();
assert_eq!(me(base, exp, modulus), BigUint::zero());
// others
base = BigUint::parse_bytes(b"12345", 10).unwrap();
exp = BigUint::parse_bytes(b"789", 10).unwrap();
modulus = BigUint::parse_bytes(b"97", 10).unwrap();
assert_eq!(me(base, exp, modulus), BigUint::parse_bytes(b"55", 10).unwrap());
}
#[test]
fn identity() {