revm_precompile/bls12_381/
map_fp_to_g1.rs

1//! BLS12-381 map fp to g1 precompile. More details in [`map_fp_to_g1`]
2use super::utils::{pad_g1_point, remove_fp_padding};
3use crate::{
4    bls12_381_const::{MAP_FP_TO_G1_ADDRESS, MAP_FP_TO_G1_BASE_GAS_FEE, PADDED_FP_LENGTH},
5    crypto, eth_precompile_fn, EthPrecompileOutput, EthPrecompileResult, Precompile,
6    PrecompileHalt, PrecompileId,
7};
8
9eth_precompile_fn!(map_fp_to_g1_precompile, map_fp_to_g1);
10
11/// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_MAP_FP_TO_G1 precompile.
12pub const PRECOMPILE: Precompile = Precompile::new(
13    PrecompileId::Bls12MapFpToGp1,
14    MAP_FP_TO_G1_ADDRESS,
15    map_fp_to_g1_precompile,
16);
17
18/// Field-to-curve call expects 64 bytes as an input that is interpreted as an
19/// element of Fp. Output of this call is 128 bytes and is an encoded G1 point.
20/// See also: <https://eips.ethereum.org/EIPS/eip-2537#abi-for-mapping-fp-element-to-g1-point>
21pub fn map_fp_to_g1(input: &[u8], gas_limit: u64) -> EthPrecompileResult {
22    if MAP_FP_TO_G1_BASE_GAS_FEE > gas_limit {
23        return Err(PrecompileHalt::OutOfGas);
24    }
25
26    if input.len() != PADDED_FP_LENGTH {
27        return Err(PrecompileHalt::Bls12381MapFpToG1InputLength);
28    }
29
30    let input_p0 = remove_fp_padding(input)?;
31
32    let unpadded_result = crypto().bls12_381_fp_to_g1(input_p0)?;
33
34    // Pad the result for EVM compatibility
35    let padded_result = pad_g1_point(&unpadded_result);
36
37    Ok(EthPrecompileOutput::new(
38        MAP_FP_TO_G1_BASE_GAS_FEE,
39        padded_result.into(),
40    ))
41}
42
43#[cfg(test)]
44mod test {
45    use super::*;
46    use primitives::{hex, Bytes};
47
48    #[test]
49    fn sanity_test() {
50        let input = Bytes::from(hex!("000000000000000000000000000000006900000000000000636f6e7472616374595a603f343061cd305a03f40239f5ffff31818185c136bc2595f2aa18e08f17"));
51        let fail = map_fp_to_g1(&input, MAP_FP_TO_G1_BASE_GAS_FEE);
52        assert_eq!(fail, Err(PrecompileHalt::NonCanonicalFp));
53    }
54}
revm_precompile/bls12_381/map_fp_to_g1.rs

revm_precompile/bls12_381/
map_fp_to_g1.rs
