From 75964cf6da129a78bbcabf0c10f9638cb5498fe0 Mon Sep 17 00:00:00 2001
From: Luke Parker <lukeparker5132@gmail.com>
Date: Tue, 19 Aug 2025 21:45:59 -0400
Subject: [PATCH] Place Schnorr signature aggregation behind a feature flag

---
 Cargo.lock                      | 2 +-
 coordinator/Cargo.toml          | 2 +-
 crypto/schnorr/Cargo.toml       | 3 ++-
 crypto/schnorr/src/lib.rs       | 1 +
 crypto/schnorr/src/tests/mod.rs | 9 +++++----
 5 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 6cef2eab..91e51d24 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -7845,7 +7845,7 @@ dependencies = [
 
 [[package]]
 name = "schnorr-signatures"
-version = "0.5.1"
+version = "0.5.2"
 dependencies = [
  "ciphersuite",
  "dalek-ff-group",
diff --git a/coordinator/Cargo.toml b/coordinator/Cargo.toml
index 1067fbb0..aa1c489d 100644
--- a/coordinator/Cargo.toml
+++ b/coordinator/Cargo.toml
@@ -26,7 +26,7 @@ blake2 = { version = "0.10", default-features = false, features = ["std"] }
 
 transcript = { package = "flexible-transcript", path = "../crypto/transcript", default-features = false, features = ["std", "recommended"] }
 ciphersuite = { path = "../crypto/ciphersuite", default-features = false, features = ["std"] }
-schnorr = { package = "schnorr-signatures", path = "../crypto/schnorr", default-features = false, features = ["std"] }
+schnorr = { package = "schnorr-signatures", path = "../crypto/schnorr", default-features = false, features = ["std", "aggregate"] }
 dkg-musig = { path = "../crypto/dkg/musig", default-features = false, features = ["std"] }
 frost = { package = "modular-frost", path = "../crypto/frost" }
 frost-schnorrkel = { path = "../crypto/schnorrkel" }
diff --git a/crypto/schnorr/Cargo.toml b/crypto/schnorr/Cargo.toml
index 2ea04f5b..8cc11325 100644
--- a/crypto/schnorr/Cargo.toml
+++ b/crypto/schnorr/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "schnorr-signatures"
-version = "0.5.1"
+version = "0.5.2"
 description = "Minimal Schnorr signatures crate hosting common code"
 license = "MIT"
 repository = "https://github.com/serai-dex/serai/tree/develop/crypto/schnorr"
@@ -39,5 +39,6 @@ dalek-ff-group = { path =  "../dalek-ff-group" }
 ciphersuite = { path = "../ciphersuite", features = ["ed25519"] }
 
 [features]
+aggregate = []
 std = ["std-shims/std", "rand_core/std", "zeroize/std", "transcript/std", "ciphersuite/std", "multiexp/std"]
 default = ["std"]
diff --git a/crypto/schnorr/src/lib.rs b/crypto/schnorr/src/lib.rs
index ecca87f7..e5b9f3c2 100644
--- a/crypto/schnorr/src/lib.rs
+++ b/crypto/schnorr/src/lib.rs
@@ -25,6 +25,7 @@ use ciphersuite::{
 use multiexp::{multiexp_vartime, BatchVerifier};
 
 /// Half-aggregation from <https://eprint.iacr.org/2021/350>.
+#[cfg(feature = "aggregate")]
 pub mod aggregate;
 
 #[cfg(test)]
diff --git a/crypto/schnorr/src/tests/mod.rs b/crypto/schnorr/src/tests/mod.rs
index 47bd9bc3..97d569db 100644
--- a/crypto/schnorr/src/tests/mod.rs
+++ b/crypto/schnorr/src/tests/mod.rs
@@ -9,10 +9,9 @@ use ciphersuite::{
 };
 use multiexp::BatchVerifier;
 
-use crate::{
-  SchnorrSignature,
-  aggregate::{SchnorrAggregator, SchnorrAggregate},
-};
+use crate::SchnorrSignature;
+#[cfg(feature = "aggregate")]
+use crate::aggregate::{SchnorrAggregator, SchnorrAggregate};
 
 mod rfc8032;
 
@@ -77,6 +76,7 @@ pub(crate) fn batch_verify<C: Ciphersuite>() {
   }
 }
 
+#[cfg(feature = "aggregate")]
 pub(crate) fn aggregate<C: Ciphersuite>() {
   const DST: &[u8] = b"Schnorr Aggregator Test";
 
@@ -117,5 +117,6 @@ fn test() {
   sign::<Ed25519>();
   verify::<Ed25519>();
   batch_verify::<Ed25519>();
+  #[cfg(feature = "aggregate")]
   aggregate::<Ed25519>();
 }