orchard/src/bundle/batch.rs

94 lines
3.1 KiB
Rust

use halo2_proofs::plonk;
use pasta_curves::vesta;
use rand::{CryptoRng, RngCore};
use tracing::debug;
use super::{Authorized, Bundle};
use crate::{
circuit::VerifyingKey,
primitives::redpallas::{self, Binding, SpendAuth},
};
/// A signature within an authorized Orchard bundle.
#[derive(Debug)]
struct BundleSignature {
/// The signature item for validation.
signature: redpallas::batch::Item<SpendAuth, Binding>,
}
/// Batch validation context for Orchard.
///
/// This batch-validates proofs and RedPallas signatures.
#[derive(Debug, Default)]
pub struct BatchValidator {
proofs: plonk::BatchVerifier<vesta::Affine>,
signatures: Vec<BundleSignature>,
}
impl BatchValidator {
/// Constructs a new batch validation context.
pub fn new() -> Self {
BatchValidator {
proofs: plonk::BatchVerifier::new(),
signatures: vec![],
}
}
/// Adds the proof and RedPallas signatures from the given bundle to the validator.
pub fn add_bundle<V: Copy + Into<i64>>(
&mut self,
bundle: &Bundle<Authorized, V>,
sighash: [u8; 32],
) {
for action in bundle.actions().iter() {
self.signatures.push(BundleSignature {
signature: action
.rk()
.create_batch_item(action.authorization().clone(), &sighash),
});
}
self.signatures.push(BundleSignature {
signature: bundle
.binding_validating_key()
.create_batch_item(bundle.authorization().binding_signature().clone(), &sighash),
});
bundle
.authorization()
.proof()
.add_to_batch(&mut self.proofs, bundle.to_instances());
}
/// Batch-validates the accumulated bundles.
///
/// Returns `true` if every proof and signature in every bundle added to the batch
/// validator is valid, or `false` if one or more are invalid. No attempt is made to
/// figure out which of the accumulated bundles might be invalid; if that information
/// is desired, construct separate [`BatchValidator`]s for sub-batches of the bundles.
pub fn validate<R: RngCore + CryptoRng>(self, vk: &VerifyingKey, rng: R) -> bool {
// https://p.z.cash/TCR:bad-txns-orchard-binding-signature-invalid?partial
if self.signatures.is_empty() {
// An empty batch is always valid, but is not free to run; skip it.
// Note that a transaction has at least a binding signature, so if
// there are no signatures, there are also no proofs.
return true;
}
let mut validator = redpallas::batch::Verifier::new();
for sig in self.signatures.iter() {
validator.queue(sig.signature.clone());
}
match validator.verify(rng) {
// If signatures are valid, check the proofs.
Ok(()) => self.proofs.finalize(&vk.params, &vk.vk),
Err(e) => {
debug!("RedPallas batch validation failed: {}", e);
false
}
}
}
}