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Author: matthiasgeihs

packages/keyring-eth-mpc/src/mpc-keyring.ts

@@ -301,6 +301,8 @@ export class MPCKeyring implements Keyring {
       networkSession,
     });
 
+    // NOTE: We could create an Ethereum compliant signature more efficiently if
+    // the signing library provided the parity bit.
     return toEthSig(signature, hash, publicKey);
   }
 }

packages/keyring-eth-mpc/src/util.ts

@@ -77,6 +77,8 @@ export function toEthSig(
     throw new Error('Invalid signature length');
   }
 
+  // Enforce low S value
+
   const rBuf = signature.slice(0, 32);
   let sBuf = signature.slice(32, 64);
 
@@ -93,6 +95,8 @@ export function toEthSig(
     }
   }
 
+  // Recover parity bit
+
   const expectedAddr = publicToAddressHex(pubKey);
 
   for (const candidateV of [0n, 1n]) {