From 54d3fc0af2c6e012f234358b5dd2722172c61238 Mon Sep 17 00:00:00 2001
From: Gary Yu <gairy.yu@gmail.com>
Date: Fri, 17 Aug 2018 23:18:48 +0800
Subject: [PATCH] improve: use batch verification for txhashset rangeproof
 validation (#1321) (#1363)

* improve: use bullet rangeproof batch verification for txhashset validation (#1321)

* update rust-secp256k1-zkp to tag 'grin_integration_22'
---
 chain/src/txhashset.rs       | 23 +++++++++++++++++++++--
 core/src/core/transaction.rs | 13 +++++++++++++
 util/Cargo.toml              |  2 +-
 3 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/chain/src/txhashset.rs b/chain/src/txhashset.rs
index 2425bf1ef..7bc3571b7 100644
--- a/chain/src/txhashset.rs
+++ b/chain/src/txhashset.rs
@@ -989,20 +989,27 @@ impl<'a> Extension<'a> {
 	{
 		let now = Instant::now();
 
+		let mut commits:Vec<Commitment> = vec![];
+		let mut proofs:Vec<RangeProof> = vec![];
+
 		let mut proof_count = 0;
 		let total_rproofs = pmmr::n_leaves(self.output_pmmr.unpruned_size());
 		for n in 1..self.output_pmmr.unpruned_size() + 1 {
 			if pmmr::is_leaf(n) {
 				if let Some(out) = self.output_pmmr.get_data(n) {
 					if let Some(rp) = self.rproof_pmmr.get_data(n) {
-						out.into_output(rp).verify_proof()?;
+						commits.push(out.commit);
+						proofs.push(rp);
 					} else {
 						// TODO - rangeproof not found
 						return Err(ErrorKind::OutputNotFound.into());
 					}
 					proof_count += 1;
 
-					if proof_count % 500 == 0 {
+					if proofs.len() >= 1000 {
+						Output::batch_verify_proofs(&commits, &proofs)?;
+						commits.clear();
+						proofs.clear();
 						debug!(
 							LOGGER,
 							"txhashset: verify_rangeproofs: verified {} rangeproofs", proof_count,
@@ -1014,6 +1021,18 @@ impl<'a> Extension<'a> {
 				status.on_validation(0, 0, proof_count, total_rproofs);
 			}
 		}
+
+		// remaining part which not full of 1000 range proofs
+		if proofs.len() > 0 {
+			Output::batch_verify_proofs(&commits, &proofs)?;
+			commits.clear();
+			proofs.clear();
+			debug!(
+				LOGGER,
+				"txhashset: verify_rangeproofs: verified {} rangeproofs", proof_count,
+			);
+		}
+
 		debug!(
 			LOGGER,
 			"txhashset: verified {} rangeproofs, pmmr size {}, took {}s",
diff --git a/core/src/core/transaction.rs b/core/src/core/transaction.rs
index 28f4bb393..ca9f491ac 100644
--- a/core/src/core/transaction.rs
+++ b/core/src/core/transaction.rs
@@ -993,6 +993,19 @@ impl Output {
 			Err(e) => Err(e),
 		}
 	}
+
+	/// Batch validates the range proofs using the commitments
+	pub fn batch_verify_proofs(
+		commits: &Vec<Commitment>,
+		proofs: &Vec<RangeProof>,
+	) -> Result<(), secp::Error> {
+		let secp = static_secp_instance();
+		let secp = secp.lock().unwrap();
+		match secp.verify_bullet_proof_multi(commits.clone(), proofs.clone(), None) {
+			Ok(_) => Ok(()),
+			Err(e) => Err(e),
+		}
+	}
 }
 
 /// An output_identifier can be build from either an input _or_ an output and
diff --git a/util/Cargo.toml b/util/Cargo.toml
index 26955c5fd..5573f45f1 100644
--- a/util/Cargo.toml
+++ b/util/Cargo.toml
@@ -20,6 +20,6 @@ zip = "0.4"
 
 [dependencies.secp256k1zkp]
 git = "https://github.com/mimblewimble/rust-secp256k1-zkp"
-tag = "grin_integration_21"
+tag = "grin_integration_22"
 #path = "../../rust-secp256k1-zkp"
 features = ["bullet-proof-sizing"]