Merge pull request #5307 from paritytech/eip-212

EIP-212 (bn128 curve pairing)
This commit is contained in:
Robert Habermeier 2017-04-21 13:10:57 +02:00 committed by GitHub
commit 0768ce3600
3 changed files with 182 additions and 4 deletions

8
Cargo.lock generated
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@ -181,8 +181,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "bn"
version = "0.4.3"
source = "git+https://github.com/paritytech/bn#59d848e642ad1ff0d60e39348576a6f11ee123b8"
version = "0.4.4"
source = "git+https://github.com/paritytech/bn#b97e95a45f4484a41a515338c4f0e093bf6675e0"
dependencies = [
"byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
"rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
@ -394,7 +394,7 @@ version = "1.7.0"
dependencies = [
"bit-set 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
"bloomchain 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
"bn 0.4.3 (git+https://github.com/paritytech/bn)",
"bn 0.4.4 (git+https://github.com/paritytech/bn)",
"byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
"clippy 0.0.103 (registry+https://github.com/rust-lang/crates.io-index)",
"crossbeam 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
@ -2797,7 +2797,7 @@ dependencies = [
"checksum bitflags 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "aad18937a628ec6abcd26d1489012cc0e18c21798210f491af69ded9b881106d"
"checksum blastfig 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "09640e0509d97d5cdff03a9f5daf087a8e04c735c3b113a75139634a19cfc7b2"
"checksum bloomchain 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3f421095d2a76fc24cd3fb3f912b90df06be7689912b1bdb423caefae59c258d"
"checksum bn 0.4.3 (git+https://github.com/paritytech/bn)" = "<none>"
"checksum bn 0.4.4 (git+https://github.com/paritytech/bn)" = "<none>"
"checksum byteorder 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c40977b0ee6b9885c9013cd41d9feffdd22deb3bb4dc3a71d901cc7a77de18c8"
"checksum bytes 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c129aff112dcc562970abb69e2508b40850dd24c274761bb50fb8a0067ba6c27"
"checksum bytes 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "46112a0060ae15e3a3f9a445428a53e082b91215b744fa27a1948842f4a64b96"

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@ -193,6 +193,7 @@
"0000000000000000000000000000000000000005": { "builtin": { "name": "modexp", "activate_at": "0x7fffffffffffff", "pricing": { "modexp": { "divisor": 20 } } } },
"0000000000000000000000000000000000000006": { "builtin": { "name": "bn128_add", "activate_at": "0x7fffffffffffff", "pricing": { "linear": { "base": 999999, "word": 0 } } } },
"0000000000000000000000000000000000000007": { "builtin": { "name": "bn128_mul", "activate_at": "0x7fffffffffffff", "pricing": { "linear": { "base": 999999, "word": 0 } } } },
"0000000000000000000000000000000000000008": { "builtin": { "name": "bn128_pairing", "activate_at": "0x7fffffffffffff", "pricing": { "linear": { "base": 999999, "word": 0 } } } },
"3282791d6fd713f1e94f4bfd565eaa78b3a0599d": {
"balance": "1337000000000000000000"
},

View File

@ -158,6 +158,7 @@ fn ethereum_builtin(name: &str) -> Box<Impl> {
"modexp" => Box::new(ModexpImpl) as Box<Impl>,
"bn128_add" => Box::new(Bn128AddImpl) as Box<Impl>,
"bn128_mul" => Box::new(Bn128MulImpl) as Box<Impl>,
"bn128_pairing" => Box::new(Bn128PairingImpl) as Box<Impl>,
_ => panic!("invalid builtin name: {}", name),
}
}
@ -191,6 +192,9 @@ 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);
@ -393,11 +397,109 @@ impl Impl for Bn128MulImpl {
}
}
mod bn128_gen {
use bn::{AffineG1, AffineG2, Fq, Fq2, G1, G2, Gt, pairing};
lazy_static! {
pub static ref P1: G1 = G1::from(AffineG1::new(
Fq::from_str("1").expect("1 is a valid field element"),
Fq::from_str("2").expect("2 is a valid field element"),
).expect("Generator P1(1, 2) is a valid curve point"));
}
lazy_static! {
pub static ref P2: G2 = G2::from(AffineG2::new(
Fq2::new(
Fq::from_str("10857046999023057135944570762232829481370756359578518086990519993285655852781")
.expect("a valid field element"),
Fq::from_str("11559732032986387107991004021392285783925812861821192530917403151452391805634")
.expect("a valid field element"),
),
Fq2::new(
Fq::from_str("8495653923123431417604973247489272438418190587263600148770280649306958101930")
.expect("a valid field element"),
Fq::from_str("4082367875863433681332203403145435568316851327593401208105741076214120093531")
.expect("a valid field element"),
),
).expect("the generator P2(10857046999023057135944570762232829481370756359578518086990519993285655852781 + 11559732032986387107991004021392285783925812861821192530917403151452391805634i, 8495653923123431417604973247489272438418190587263600148770280649306958101930 + 4082367875863433681332203403145435568316851327593401208105741076214120093531i) is a valid curve point"));
}
lazy_static! {
pub static ref P1_P2_PAIRING: Gt = pairing(P1.clone(), P2.clone());
}
}
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> {
use bn::{AffineG1, AffineG2, Fq, Fq2, pairing, G1, G2, Gt};
let elements = input.len() / 192; // (a, b_a, b_b - each 64-byte affine coordinates)
if input.len() % 192 != 0 {
return Err("Invalid input length, must be multiple of 192 (3 * (32*2))".into())
}
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_b_x = Fq::from_slice(&input[idx*192+64..idx*192+96])
.map_err(|_| Error::from("Invalid b argument imaginary coeff x coordinate"))?;
let b_b_y = Fq::from_slice(&input[idx*192+96..idx*192+128])
.map_err(|_| Error::from("Invalid b argument imaginary coeff y coordinate"))?;
let b_a_x = Fq::from_slice(&input[idx*192+128..idx*192+160])
.map_err(|_| Error::from("Invalid b argument real coeff x coordinate"))?;
let b_a_y = Fq::from_slice(&input[idx*192+160..idx*192+192])
.map_err(|_| Error::from("Invalid b argument real coeff y coordinate"))?;
vals.push((
G1::from(
AffineG1::new(a_x, a_y).map_err(|_| Error::from("Invalid a argument - not on curve"))?
),
G2::from(
AffineG2::new(
Fq2::new(b_a_x, b_a_y),
Fq2::new(b_b_x, b_b_y),
).map_err(|_| Error::from("Invalid b argument - not on curve"))?
),
));
};
let mul = vals.into_iter().fold(Gt::one(), |s, (a, b)| s * pairing(a, b));
if mul == *bn128_gen::P1_P2_PAIRING {
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, Modexp};
use ethjson;
use util::{U256, BytesRef};
use rustc_serialize::hex::FromHex;
#[test]
fn identity() {
@ -713,7 +815,82 @@ mod tests {
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("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]