Add signature verification to aggregate_partial_signatures (#417)

chainwayxyz · Jan 15, 2025 · 4922146 · 4922146
1 parent 6d83a3f
commit 4922146
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Showing 2 changed files with 14 additions and 9 deletions.
diff --git a/core/src/errors.rs b/core/src/errors.rs
@@ -13,12 +13,15 @@ use thiserror::Error;
 #[derive(Debug, Error)]
 #[non_exhaustive]
 pub enum BridgeError {
-    /// Returned when the secp256k1 crate returns an error
+    /// Returned when the bitcoin::secp256k1 crate returns an error
     #[error("Secpk256Error: {0}")]
-    Secp256k1Error(#[from] bitcoin::secp256k1::Error),
+    BitcoinSecp256k1Error(#[from] bitcoin::secp256k1::Error),
     /// Returned when the bitcoin crate returns an error in the sighash taproot module
     #[error("BitcoinSighashTaprootError: {0}")]
     BitcoinSighashTaprootError(#[from] bitcoin::sighash::TaprootError),
+    /// Returned when the secp256k1 crate returns an error
+    #[error("Secp256k1Error: {0}")]
+    Secp256k1Error(#[from] secp256k1::Error),
     /// Returned when a non finalized deposit request is found
     #[error("DepositNotFinalized")]
     DepositNotFinalized,

diff --git a/core/src/musig2.rs b/core/src/musig2.rs
@@ -11,7 +11,7 @@ use bitcoin::{
 };
 use secp256k1::{
     musig::{
-        new_musig_nonce_pair, MusigAggNonce, MusigKeyAggCache, MusigPartialSignature,
+        self, new_musig_nonce_pair, MusigAggNonce, MusigKeyAggCache, MusigPartialSignature,
         MusigPubNonce, MusigSecNonce, MusigSecRand, MusigSession,
     },
     rand::Rng,
@@ -117,15 +117,17 @@ pub fn aggregate_partial_signatures(
     message: Message,
 ) -> Result<schnorr::Signature, BridgeError> {
     let musig_key_agg_cache = create_key_agg_cache(pks, tweak);
+    let secp_message = to_secp_msg(&message);
 
-    let session = MusigSession::new(
-        SECP256K1,
-        &musig_key_agg_cache,
-        agg_nonce,
-        to_secp_msg(&message),
-    );
+    let session = MusigSession::new(SECP256K1, &musig_key_agg_cache, agg_nonce, secp_message);
 
     let partial_sigs: Vec<&MusigPartialSignature> = partial_sigs.iter().collect();
+    let final_sig = session.partial_sig_agg(&partial_sigs);
+    SECP256K1.verify_schnorr(
+        &final_sig,
+        secp_message.as_ref(),
+        &musig_key_agg_cache.agg_pk(),
+    )?; // TODO: Change this later
 
     Ok(from_secp_sig(session.partial_sig_agg(&partial_sigs)))
 }