curvy-core 0.1.0-rc.3

Curvy privacy-protocol crypto core (Poseidon, BabyJubjub, note commitments, stealth addressing)
Documentation 
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//! Misc hash helpers - a faithful port of `proving/utils.ts`.

use num_bigint::BigUint;
use sha2::{Digest, Sha256};

use crate::encoding::biguint_to_be_32;

/// `sha256BigInt`: 32-byte big-endian pack each input, concatenate, SHA-256, then
/// interpret the 32-byte digest as a big-endian integer - **no field reduction**
/// (this is the `inputHash` digest the v2 pending-commit circuit verifies against).
///
/// Inputs are **raw 256-bit integers**, not field elements: the TS packs each
/// `bigint` directly (it is documented to handle full 256-bit values), so values in
/// `[modulus, 2^256)` are hashed literally rather than reduced. Panics on a value
/// `>= 2^256` (matches the TS `bigIntToBytes` overflow guard).
pub fn sha256_bigint(inputs: &[BigUint]) -> BigUint {
    let mut h = Sha256::new();
    for x in inputs {
        h.update(biguint_to_be_32(x));
    }
    BigUint::from_bytes_be(&h.finalize())
}