revm_precompile/bls12_381/
g2_add.rs

1//! BLS12-381 G2 add precompile. More details in [`g2_add`]
2use super::utils::{pad_g2_point, remove_g2_padding};
3use crate::bls12_381_const::{
4    G2_ADD_ADDRESS, G2_ADD_BASE_GAS_FEE, G2_ADD_INPUT_LENGTH, PADDED_G2_LENGTH,
5};
6use crate::{crypto, PrecompileError, PrecompileOutput, PrecompileResult, PrecompileWithAddress};
7
8/// [EIP-2537](https://eips.ethereum.org/EIPS/eip-2537#specification) BLS12_G2ADD precompile.
9pub const PRECOMPILE: PrecompileWithAddress = PrecompileWithAddress(G2_ADD_ADDRESS, g2_add);
10
11/// G2 addition call expects `512` bytes as an input that is interpreted as byte
12/// concatenation of two G2 points (`256` bytes each).
13///
14/// Output is an encoding of addition operation result - single G2 point (`256`
15/// bytes).
16/// See also <https://eips.ethereum.org/EIPS/eip-2537#abi-for-g2-addition>
17pub fn g2_add(input: &[u8], gas_limit: u64) -> PrecompileResult {
18    if G2_ADD_BASE_GAS_FEE > gas_limit {
19        return Err(PrecompileError::OutOfGas);
20    }
21
22    if input.len() != G2_ADD_INPUT_LENGTH {
23        return Err(PrecompileError::Other(format!(
24            "G2ADD input should be {G2_ADD_INPUT_LENGTH} bytes, was {}",
25            input.len()
26        )));
27    }
28
29    // Extract coordinates from padded input
30    let [a_x_0, a_x_1, a_y_0, a_y_1] = remove_g2_padding(&input[..PADDED_G2_LENGTH])?;
31    let [b_x_0, b_x_1, b_y_0, b_y_1] = remove_g2_padding(&input[PADDED_G2_LENGTH..])?;
32
33    let a = (*a_x_0, *a_x_1, *a_y_0, *a_y_1);
34    let b = (*b_x_0, *b_x_1, *b_y_0, *b_y_1);
35
36    let unpadded_result = crypto().bls12_381_g2_add(a, b)?;
37
38    // Pad the result for EVM compatibility
39    let padded_result = pad_g2_point(&unpadded_result);
40
41    Ok(PrecompileOutput::new(
42        G2_ADD_BASE_GAS_FEE,
43        padded_result.into(),
44    ))
45}
revm_precompile/bls12_381/g2_add.rs

revm_precompile/bls12_381/
g2_add.rs
