fix(syscall): handle invalid input in bn256 syscalls #1022
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| fn read_pt(buf: &[u8]) -> Result<G1> { | ||
| let map_err = BnError::G1FieldError; | ||
| let px = Fq::from_slice(&buf[0..32]).map_err(map_err)?; | ||
| let py = Fq::from_slice(&buf[32..64]).map_err(map_err)?; | ||
| Ok(if px == Fq::zero() && py == Fq::zero() { | ||
| G1::zero() |
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Is this a breaking change? (is AffineG1(Fq::zero(), Fq::zero()) == G1::zero()? )
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Well, actually I don't break any change here. But after checking the code, looks like AffineG1(Fq::zero(), Fq::zero()) and G1::zero() are not equivalent.
G1::zero() represents:
G {
x: P::Base::zero(),
y: P::Base::one(),
z: P::Base::zero(),
}And for AffineG1(Fq::zero(), Fq::zero()):
G {
x: x,
y: y,
z: P::Base::one(),
};@Flouse Do you remember about this? Is that intended?
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Yes, that is intended.
As my understanding, when px == Fq::zero() && py == Fq::zero(),
it is a special coordinate at infinity with z == P::Base::zero().
similar implementation: https://github.com/openethereum/parity-ethereum/blob/c7f608ec740882eac94038249037ddd955b60d31/ethcore/src/builtin.rs#L408-L414
Fix bn256 test cases
Flouse
changed the title
Handle errors in bn256 and return errors for syscalls.