size check added

boltlabs-inc · Aug 24, 2023 · c9cc244 · c9cc244
1 parent 2ac1bbd
commit c9cc244
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/src/auxinfo/auxinfo_commit.rs b/src/auxinfo/auxinfo_commit.rs
@@ -10,9 +10,11 @@ use crate::{
     auxinfo::{info::AuxInfoPublic, participant::AuxInfoParticipant},
     errors::{InternalError, Result},
     messages::{AuxinfoMessageType, Message, MessageType},
+    parameters::ELL,
     participant::{InnerProtocolParticipant, ProtocolParticipant},
     protocol::{Identifier, ParticipantIdentifier},
 };
+use libpaillier::unknown_order::BigNumber;
 use merlin::Transcript;
 use rand::{CryptoRng, RngCore};
 use serde::{Deserialize, Serialize};
@@ -123,6 +125,9 @@ impl CommitmentScheme {
         // Public parameters in this decommit must be consistent with each other
         scheme.clone().public_key.verify(context)?;
 
+        let lower_bound = BigNumber::one() << ELL;
+        assert!(scheme.public_key.params().scheme().modulus() >= &lower_bound);
+
         // Owner must be consistent across message, public keys, and decommit
         if scheme.public_key.participant() != scheme.pid {
             error!(