openethereum/ethcore/src/builtin.rs
Marek Kotewicz e95b093483 dissolve util (#7460)
* ethereum-types refactor in progress

* ethereum-types refactor in progress

* ethereum-types refactor in progress

* ethereum-types refactor in progress

* ethereum-types refactor finished

* removed obsolete util/src/lib.rs

* removed commented out code
2018-01-10 15:35:18 +03:00

1056 lines
34 KiB
Rust

// Copyright 2015-2017 Parity Technologies (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/>.
use std::cmp::{max, min};
use std::io::{self, Read};
use byteorder::{ByteOrder, BigEndian};
use crypto::sha2::Sha256 as Sha256Digest;
use crypto::ripemd160::Ripemd160 as Ripemd160Digest;
use crypto::digest::Digest;
use num::{BigUint, Zero, One};
use hash::keccak;
use ethereum_types::{H256, U256};
use bytes::BytesRef;
use ethkey::{Signature, recover as ec_recover};
use ethjson;
#[derive(Debug)]
pub struct Error(pub &'static str);
impl From<&'static str> for Error {
fn from(val: &'static str) -> Self {
Error(val)
}
}
impl Into<::vm::Error> for Error {
fn into(self) -> ::vm::Error {
::vm::Error::BuiltIn(self.0)
}
}
/// Native implementation of a built-in contract.
pub trait Impl: Send + Sync {
/// execute this built-in on the given input, writing to the given output.
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error>;
}
/// A gas pricing scheme for built-in contracts.
pub trait Pricer: Send + Sync {
/// The gas cost of running this built-in for the given input data.
fn cost(&self, input: &[u8]) -> U256;
}
/// A linear pricing model. This computes a price using a base cost and a cost per-word.
struct Linear {
base: usize,
word: usize,
}
/// A special pricing model for modular exponentiation.
struct ModexpPricer {
divisor: usize,
}
impl Pricer for Linear {
fn cost(&self, input: &[u8]) -> U256 {
U256::from(self.base) + U256::from(self.word) * U256::from((input.len() + 31) / 32)
}
}
/// A alt_bn128_parinig pricing model. This computes a price using a base cost and a cost per pair.
struct AltBn128PairingPricer {
base: usize,
pair: usize,
}
impl Pricer for AltBn128PairingPricer {
fn cost(&self, input: &[u8]) -> U256 {
let cost = U256::from(self.base) + U256::from(self.pair) * U256::from(input.len() / 192);
cost
}
}
impl Pricer for ModexpPricer {
fn cost(&self, input: &[u8]) -> U256 {
let mut reader = input.chain(io::repeat(0));
let mut buf = [0; 32];
// read lengths as U256 here for accurate gas calculation.
let mut read_len = || {
reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
U256::from(H256::from_slice(&buf[..]))
};
let base_len = read_len();
let exp_len = read_len();
let mod_len = read_len();
if mod_len.is_zero() && base_len.is_zero() {
return U256::zero()
}
let max_len = U256::from(u32::max_value() / 2);
if base_len > max_len || mod_len > max_len || exp_len > max_len {
return U256::max_value();
}
let (base_len, exp_len, mod_len) = (base_len.low_u64(), exp_len.low_u64(), mod_len.low_u64());
let m = max(mod_len, base_len);
// read fist 32-byte word of the exponent.
let exp_low = if base_len + 96 >= input.len() as u64 { U256::zero() } else {
let mut buf = [0; 32];
let mut reader = input[(96 + base_len as usize)..].chain(io::repeat(0));
let len = min(exp_len, 32) as usize;
reader.read_exact(&mut buf[(32 - len)..]).expect("reading from zero-extended memory cannot fail; qed");
U256::from(H256::from_slice(&buf[..]))
};
let adjusted_exp_len = Self::adjusted_exp_len(exp_len, exp_low);
let (gas, overflow) = Self::mult_complexity(m).overflowing_mul(max(adjusted_exp_len, 1));
if overflow {
return U256::max_value();
}
(gas / self.divisor as u64).into()
}
}
impl ModexpPricer {
fn adjusted_exp_len(len: u64, exp_low: U256) -> u64 {
let bit_index = if exp_low.is_zero() { 0 } else { (255 - exp_low.leading_zeros()) as u64 };
if len <= 32 {
bit_index
} else {
8 * (len - 32) + bit_index
}
}
fn mult_complexity(x: u64) -> u64 {
match x {
x if x <= 64 => x * x,
x if x <= 1024 => (x * x) / 4 + 96 * x - 3072,
x => (x * x) / 16 + 480 * x - 199680,
}
}
}
/// Pricing scheme, execution definition, and activation block for a built-in contract.
///
/// Call `cost` to compute cost for the given input, `execute` to execute the contract
/// on the given input, and `is_active` to determine whether the contract is active.
///
/// Unless `is_active` is true,
pub struct Builtin {
pricer: Box<Pricer>,
native: Box<Impl>,
activate_at: u64,
}
impl Builtin {
/// Simple forwarder for cost.
pub fn cost(&self, input: &[u8]) -> U256 { self.pricer.cost(input) }
/// Simple forwarder for execute.
pub fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
self.native.execute(input, output)
}
/// Whether the builtin is activated at the given block number.
pub fn is_active(&self, at: u64) -> bool { at >= self.activate_at }
}
impl From<ethjson::spec::Builtin> for Builtin {
fn from(b: ethjson::spec::Builtin) -> Self {
let pricer: Box<Pricer> = match b.pricing {
ethjson::spec::Pricing::Linear(linear) => {
Box::new(Linear {
base: linear.base,
word: linear.word,
})
}
ethjson::spec::Pricing::Modexp(exp) => {
Box::new(ModexpPricer {
divisor: if exp.divisor == 0 {
warn!("Zero modexp divisor specified. Falling back to default.");
10
} else {
exp.divisor
}
})
}
ethjson::spec::Pricing::AltBn128Pairing(pricer) => {
Box::new(AltBn128PairingPricer {
base: pricer.base,
pair: pricer.pair,
})
}
};
Builtin {
pricer: pricer,
native: ethereum_builtin(&b.name),
activate_at: b.activate_at.map(Into::into).unwrap_or(0),
}
}
}
// Ethereum builtin creator.
fn ethereum_builtin(name: &str) -> Box<Impl> {
match name {
"identity" => Box::new(Identity) as Box<Impl>,
"ecrecover" => Box::new(EcRecover) as Box<Impl>,
"sha256" => Box::new(Sha256) as Box<Impl>,
"ripemd160" => Box::new(Ripemd160) as Box<Impl>,
"modexp" => Box::new(ModexpImpl) as Box<Impl>,
"alt_bn128_add" => Box::new(Bn128AddImpl) as Box<Impl>,
"alt_bn128_mul" => Box::new(Bn128MulImpl) as Box<Impl>,
"alt_bn128_pairing" => Box::new(Bn128PairingImpl) as Box<Impl>,
_ => panic!("invalid builtin name: {}", name),
}
}
// Ethereum builtins:
//
// - The identity function
// - ec recovery
// - sha256
// - ripemd160
// - modexp (EIP198)
#[derive(Debug)]
struct Identity;
#[derive(Debug)]
struct EcRecover;
#[derive(Debug)]
struct Sha256;
#[derive(Debug)]
struct Ripemd160;
#[derive(Debug)]
struct ModexpImpl;
#[derive(Debug)]
struct Bn128AddImpl;
#[derive(Debug)]
struct Bn128MulImpl;
#[derive(Debug)]
struct Bn128PairingImpl;
impl Impl for Identity {
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
output.write(0, input);
Ok(())
}
}
impl Impl for EcRecover {
fn execute(&self, i: &[u8], output: &mut BytesRef) -> Result<(), Error> {
let len = min(i.len(), 128);
let mut input = [0; 128];
input[..len].copy_from_slice(&i[..len]);
let hash = H256::from_slice(&input[0..32]);
let v = H256::from_slice(&input[32..64]);
let r = H256::from_slice(&input[64..96]);
let s = H256::from_slice(&input[96..128]);
let bit = match v[31] {
27 | 28 if &v.0[..31] == &[0; 31] => v[31] - 27,
_ => { return Ok(()); },
};
let s = Signature::from_rsv(&r, &s, bit);
if s.is_valid() {
if let Ok(p) = ec_recover(&s, &hash) {
let r = keccak(p);
output.write(0, &[0; 12]);
output.write(12, &r[12..r.len()]);
}
}
Ok(())
}
}
impl Impl for Sha256 {
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
let mut sha = Sha256Digest::new();
sha.input(input);
let mut out = [0; 32];
sha.result(&mut out);
output.write(0, &out);
Ok(())
}
}
impl Impl for Ripemd160 {
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
let mut sha = Ripemd160Digest::new();
sha.input(input);
let mut out = [0; 32];
sha.result(&mut out[12..32]);
output.write(0, &out);
Ok(())
}
}
// 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;
if modulus <= BigUint::one() { // n^m % 0 || n^m % 1
return BigUint::zero();
}
if exp.is_zero() { // n^0 % m
return BigUint::one();
}
if base.is_zero() { // 0^n % m, n>0
return BigUint::zero();
}
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));
let mut buf = [0; 32];
// read lengths as usize.
// ignoring the first 24 bytes might technically lead us to fall out of consensus,
// but so would running out of addressable memory!
let mut read_len = |reader: &mut io::Chain<&[u8], io::Repeat>| {
reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
BigEndian::read_u64(&buf[24..]) as usize
};
let base_len = read_len(&mut reader);
let exp_len = read_len(&mut reader);
let mod_len = read_len(&mut reader);
// Gas formula allows arbitrary large exp_len when base and modulus are empty, so we need to handle empty base first.
let r = if base_len == 0 && mod_len == 0 {
BigUint::zero()
} else {
// read the numbers themselves.
let mut buf = vec![0; max(mod_len, max(base_len, exp_len))];
let mut read_num = |len| {
reader.read_exact(&mut buf[..len]).expect("reading from zero-extended memory cannot fail; qed");
BigUint::from_bytes_be(&buf[..len])
};
let base = read_num(base_len);
let exp = read_num(exp_len);
let modulus = read_num(mod_len);
modexp(base, exp, modulus)
};
// write output to given memory, left padded and same length as the modulus.
let bytes = r.to_bytes_be();
// always true except in the case of zero-length modulus, which leads to
// output of length and value 1.
if bytes.len() <= mod_len {
let res_start = mod_len - bytes.len();
output.write(res_start, &bytes);
}
Ok(())
}
}
fn read_fr(reader: &mut io::Chain<&[u8], io::Repeat>) -> Result<::bn::Fr, Error> {
let mut buf = [0u8; 32];
reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
::bn::Fr::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid field element"))
}
fn read_point(reader: &mut io::Chain<&[u8], io::Repeat>) -> Result<::bn::G1, Error> {
use bn::{Fq, AffineG1, G1, Group};
let mut buf = [0u8; 32];
reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
let px = Fq::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid point x coordinate"))?;
reader.read_exact(&mut buf[..]).expect("reading from zero-extended memory cannot fail; qed");
let py = Fq::from_slice(&buf[0..32]).map_err(|_| Error::from("Invalid point y coordinate"))?;
Ok(
if px == Fq::zero() && py == Fq::zero() {
G1::zero()
} else {
AffineG1::new(px, py).map_err(|_| Error::from("Invalid curve point"))?.into()
}
)
}
impl Impl for Bn128AddImpl {
// Can fail if any of the 2 points does not belong the bn128 curve
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
use bn::AffineG1;
let mut padded_input = input.chain(io::repeat(0));
let p1 = read_point(&mut padded_input)?;
let p2 = read_point(&mut padded_input)?;
let mut write_buf = [0u8; 64];
if let Some(sum) = AffineG1::from_jacobian(p1 + p2) {
// point not at infinity
sum.x().to_big_endian(&mut write_buf[0..32]).expect("Cannot fail since 0..32 is 32-byte length");
sum.y().to_big_endian(&mut write_buf[32..64]).expect("Cannot fail since 32..64 is 32-byte length");;
}
output.write(0, &write_buf);
Ok(())
}
}
impl Impl for Bn128MulImpl {
// Can fail if first paramter (bn128 curve point) does not actually belong to the curve
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
use bn::AffineG1;
let mut padded_input = input.chain(io::repeat(0));
let p = read_point(&mut padded_input)?;
let fr = read_fr(&mut padded_input)?;
let mut write_buf = [0u8; 64];
if let Some(sum) = AffineG1::from_jacobian(p * fr) {
// point not at infinity
sum.x().to_big_endian(&mut write_buf[0..32]).expect("Cannot fail since 0..32 is 32-byte length");
sum.y().to_big_endian(&mut write_buf[32..64]).expect("Cannot fail since 32..64 is 32-byte length");;
}
output.write(0, &write_buf);
Ok(())
}
}
impl Impl for Bn128PairingImpl {
/// Can fail if:
/// - input length is not a multiple of 192
/// - any of odd points does not belong to bn128 curve
/// - any of even points does not belong to the twisted bn128 curve over the field F_p^2 = F_p[i] / (i^2 + 1)
fn execute(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
if input.len() % 192 != 0 {
return Err("Invalid input length, must be multiple of 192 (3 * (32*2))".into())
}
if let Err(err) = self.execute_with_error(input, output) {
trace!("Pairining error: {:?}", err);
return Err(err)
}
Ok(())
}
}
impl Bn128PairingImpl {
fn execute_with_error(&self, input: &[u8], output: &mut BytesRef) -> Result<(), Error> {
use bn::{AffineG1, AffineG2, Fq, Fq2, pairing, G1, G2, Gt, Group};
let elements = input.len() / 192; // (a, b_a, b_b - each 64-byte affine coordinates)
let ret_val = if input.len() == 0 {
U256::one()
} else {
let mut vals = Vec::new();
for idx in 0..elements {
let a_x = Fq::from_slice(&input[idx*192..idx*192+32])
.map_err(|_| Error::from("Invalid a argument x coordinate"))?;
let a_y = Fq::from_slice(&input[idx*192+32..idx*192+64])
.map_err(|_| Error::from("Invalid a argument y coordinate"))?;
let b_a_y = Fq::from_slice(&input[idx*192+64..idx*192+96])
.map_err(|_| Error::from("Invalid b argument imaginary coeff x coordinate"))?;
let b_a_x = Fq::from_slice(&input[idx*192+96..idx*192+128])
.map_err(|_| Error::from("Invalid b argument imaginary coeff y coordinate"))?;
let b_b_y = Fq::from_slice(&input[idx*192+128..idx*192+160])
.map_err(|_| Error::from("Invalid b argument real coeff x coordinate"))?;
let b_b_x = Fq::from_slice(&input[idx*192+160..idx*192+192])
.map_err(|_| Error::from("Invalid b argument real coeff y coordinate"))?;
let b_a = Fq2::new(b_a_x, b_a_y);
let b_b = Fq2::new(b_b_x, b_b_y);
let b = if b_a.is_zero() && b_b.is_zero() {
G2::zero()
} else {
G2::from(AffineG2::new(b_a, b_b).map_err(|_| Error::from("Invalid b argument - not on curve"))?)
};
let a = if a_x.is_zero() && a_y.is_zero() {
G1::zero()
} else {
G1::from(AffineG1::new(a_x, a_y).map_err(|_| Error::from("Invalid a argument - not on curve"))?)
};
vals.push((a, b));
};
let mul = vals.into_iter().fold(Gt::one(), |s, (a, b)| s * pairing(a, b));
if mul == Gt::one() {
U256::one()
} else {
U256::zero()
}
};
let mut buf = [0u8; 32];
ret_val.to_big_endian(&mut buf);
output.write(0, &buf);
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::{Builtin, Linear, ethereum_builtin, Pricer, ModexpPricer, modexp as me};
use ethjson;
use ethereum_types::U256;
use bytes::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() {
let f = ethereum_builtin("identity");
let i = [0u8, 1, 2, 3];
let mut o2 = [255u8; 2];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o2[..])).expect("Builtin should not fail");
assert_eq!(i[0..2], o2);
let mut o4 = [255u8; 4];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o4[..])).expect("Builtin should not fail");
assert_eq!(i, o4);
let mut o8 = [255u8; 8];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..])).expect("Builtin should not fail");
assert_eq!(i, o8[..4]);
assert_eq!([255u8; 4], o8[4..]);
}
#[test]
fn sha256() {
let f = ethereum_builtin("sha256");
let i = [0u8; 0];
let mut o = [255u8; 32];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855").unwrap())[..]);
let mut o8 = [255u8; 8];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..])).expect("Builtin should not fail");
assert_eq!(&o8[..], &(FromHex::from_hex("e3b0c44298fc1c14").unwrap())[..]);
let mut o34 = [255u8; 34];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..])).expect("Builtin should not fail");
assert_eq!(&o34[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855ffff").unwrap())[..]);
let mut ov = vec![];
f.execute(&i[..], &mut BytesRef::Flexible(&mut ov)).expect("Builtin should not fail");
assert_eq!(&ov[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855").unwrap())[..]);
}
#[test]
fn ripemd160() {
let f = ethereum_builtin("ripemd160");
let i = [0u8; 0];
let mut o = [255u8; 32];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31").unwrap())[..]);
let mut o8 = [255u8; 8];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..])).expect("Builtin should not fail");
assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]);
let mut o34 = [255u8; 34];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..])).expect("Builtin should not fail");
assert_eq!(&o34[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31ffff").unwrap())[..]);
}
#[test]
fn ecrecover() {
let f = ethereum_builtin("ecrecover");
let i = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddb").unwrap())[..]);
let mut o8 = [255u8; 8];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..])).expect("Builtin should not fail");
assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]);
let mut o34 = [255u8; 34];
f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..])).expect("Builtin should not fail");
assert_eq!(&o34[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddbffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001a650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001b").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff000000000000000000000000000000000000000000000000000000000000001b").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
// TODO: Should this (corrupted version of the above) fail rather than returning some address?
/* let i_bad = FromHex::from_hex("48173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);*/
}
#[test]
fn modexp() {
let f = Builtin {
pricer: Box::new(ModexpPricer { divisor: 20 }),
native: ethereum_builtin("modexp"),
activate_at: 0,
};
// test for potential gas cost multiplication overflow
{
let input = FromHex::from_hex("0000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000003b27bafd00000000000000000000000000000000000000000000000000000000503c8ac3").unwrap();
let expected_cost = U256::max_value();
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
// test for potential exp len overflow
{
let input = FromHex::from_hex("\
00000000000000000000000000000000000000000000000000000000000000ff\
2a1e530000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000"
).unwrap();
let mut output = vec![0u8; 32];
let expected = FromHex::from_hex("0000000000000000000000000000000000000000000000000000000000000000").unwrap();
let expected_cost = U256::max_value();
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should fail");
assert_eq!(output, expected);
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
// fermat's little theorem example.
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000001\
0000000000000000000000000000000000000000000000000000000000000020\
0000000000000000000000000000000000000000000000000000000000000020\
03\
fffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2e\
fffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f"
).unwrap();
let mut output = vec![0u8; 32];
let expected = FromHex::from_hex("0000000000000000000000000000000000000000000000000000000000000001").unwrap();
let expected_cost = 13056;
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
// second example from EIP: zero base.
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000020\
0000000000000000000000000000000000000000000000000000000000000020\
fffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2e\
fffffffffffffffffffffffffffffffffffffffffffffffffffffffefffffc2f"
).unwrap();
let mut output = vec![0u8; 32];
let expected = FromHex::from_hex("0000000000000000000000000000000000000000000000000000000000000000").unwrap();
let expected_cost = 13056;
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
// another example from EIP: zero-padding
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000001\
0000000000000000000000000000000000000000000000000000000000000002\
0000000000000000000000000000000000000000000000000000000000000020\
03\
ffff\
80"
).unwrap();
let mut output = vec![0u8; 32];
let expected = FromHex::from_hex("3b01b01ac41f2d6e917c6d6a221ce793802469026d9ab7578fa2e79e4da6aaab").unwrap();
let expected_cost = 768;
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
// zero-length modulus.
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000001\
0000000000000000000000000000000000000000000000000000000000000002\
0000000000000000000000000000000000000000000000000000000000000000\
03\
ffff"
).unwrap();
let mut output = vec![];
let expected_cost = 0;
f.execute(&input[..], &mut BytesRef::Flexible(&mut output)).expect("Builtin should not fail");
assert_eq!(output.len(), 0); // shouldn't have written any output.
assert_eq!(f.cost(&input[..]), expected_cost.into());
}
}
#[test]
fn bn128_add() {
let f = Builtin {
pricer: Box::new(Linear { base: 0, word: 0 }),
native: ethereum_builtin("alt_bn128_add"),
activate_at: 0,
};
// zero-points additions
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000"
).unwrap();
let mut output = vec![0u8; 64];
let expected = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000"
).unwrap();
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
}
// no input, should not fail
{
let mut empty = [0u8; 0];
let input = BytesRef::Fixed(&mut empty);
let mut output = vec![0u8; 64];
let expected = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000"
).unwrap();
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
}
// should fail - point not on curve
{
let input = FromHex::from_hex("\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111"
).unwrap();
let mut output = vec![0u8; 64];
let res = f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..]));
assert!(res.is_err(), "There should be built-in error here");
}
}
#[test]
fn bn128_mul() {
let f = Builtin {
pricer: Box::new(Linear { base: 0, word: 0 }),
native: ethereum_builtin("alt_bn128_mul"),
activate_at: 0,
};
// zero-point multiplication
{
let input = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000\
0200000000000000000000000000000000000000000000000000000000000000"
).unwrap();
let mut output = vec![0u8; 64];
let expected = FromHex::from_hex("\
0000000000000000000000000000000000000000000000000000000000000000\
0000000000000000000000000000000000000000000000000000000000000000"
).unwrap();
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
}
// should fail - point not on curve
{
let input = FromHex::from_hex("\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
0f00000000000000000000000000000000000000000000000000000000000000"
).unwrap();
let mut output = vec![0u8; 64];
let res = f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..]));
assert!(res.is_err(), "There should be built-in error here");
}
}
fn builtin_pairing() -> Builtin {
Builtin {
pricer: Box::new(Linear { base: 0, word: 0 }),
native: ethereum_builtin("alt_bn128_pairing"),
activate_at: 0,
}
}
fn empty_test(f: Builtin, expected: Vec<u8>) {
let mut empty = [0u8; 0];
let input = BytesRef::Fixed(&mut empty);
let mut output = vec![0u8; expected.len()];
f.execute(&input[..], &mut BytesRef::Fixed(&mut output[..])).expect("Builtin should not fail");
assert_eq!(output, expected);
}
fn error_test(f: Builtin, input: &[u8], msg_contains: Option<&str>) {
let mut output = vec![0u8; 64];
let res = f.execute(input, &mut BytesRef::Fixed(&mut output[..]));
if let Some(msg) = msg_contains {
if let Err(e) = res {
if !e.0.contains(msg) {
panic!("There should be error containing '{}' here, but got: '{}'", msg, e.0);
}
}
} else {
assert!(res.is_err(), "There should be built-in error here");
}
}
fn bytes(s: &'static str) -> Vec<u8> {
FromHex::from_hex(s).expect("static str should contain valid hex bytes")
}
#[test]
fn bn128_pairing_empty() {
// should not fail, because empty input is a valid input of 0 elements
empty_test(
builtin_pairing(),
bytes("0000000000000000000000000000000000000000000000000000000000000001"),
);
}
#[test]
fn bn128_pairing_notcurve() {
// should fail - point not on curve
error_test(
builtin_pairing(),
&bytes("\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111"
),
Some("not on curve"),
);
}
#[test]
fn bn128_pairing_fragmented() {
// should fail - input length is invalid
error_test(
builtin_pairing(),
&bytes("\
1111111111111111111111111111111111111111111111111111111111111111\
1111111111111111111111111111111111111111111111111111111111111111\
111111111111111111111111111111"
),
Some("Invalid input length"),
);
}
#[test]
#[should_panic]
fn from_unknown_linear() {
let _ = ethereum_builtin("foo");
}
#[test]
fn is_active() {
let pricer = Box::new(Linear { base: 10, word: 20} );
let b = Builtin {
pricer: pricer as Box<Pricer>,
native: ethereum_builtin("identity"),
activate_at: 100_000,
};
assert!(!b.is_active(99_999));
assert!(b.is_active(100_000));
assert!(b.is_active(100_001));
}
#[test]
fn from_named_linear() {
let pricer = Box::new(Linear { base: 10, word: 20 });
let b = Builtin {
pricer: pricer as Box<Pricer>,
native: ethereum_builtin("identity"),
activate_at: 1,
};
assert_eq!(b.cost(&[0; 0]), U256::from(10));
assert_eq!(b.cost(&[0; 1]), U256::from(30));
assert_eq!(b.cost(&[0; 32]), U256::from(30));
assert_eq!(b.cost(&[0; 33]), U256::from(50));
let i = [0u8, 1, 2, 3];
let mut o = [255u8; 4];
b.execute(&i[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(i, o);
}
#[test]
fn from_json() {
let b = Builtin::from(ethjson::spec::Builtin {
name: "identity".to_owned(),
pricing: ethjson::spec::Pricing::Linear(ethjson::spec::Linear {
base: 10,
word: 20,
}),
activate_at: None,
});
assert_eq!(b.cost(&[0; 0]), U256::from(10));
assert_eq!(b.cost(&[0; 1]), U256::from(30));
assert_eq!(b.cost(&[0; 32]), U256::from(30));
assert_eq!(b.cost(&[0; 33]), U256::from(50));
let i = [0u8, 1, 2, 3];
let mut o = [255u8; 4];
b.execute(&i[..], &mut BytesRef::Fixed(&mut o[..])).expect("Builtin should not fail");
assert_eq!(i, o);
}
}