From 7999f8aa1c77741faf46b75037800da707024127 Mon Sep 17 00:00:00 2001
From: Bruce0X <109469941+Bruce039@users.noreply.github.com>
Date: Fri, 25 Sep 2026 15:55:49 +0400
Subject: [PATCH] bip375: sync vendored DLEQ code with BIP-374

bip-0375/deps/dleq.py is adapted from the BIP-374 reference code but
predates the change that treats the challenge e as a scalar (#2262).
Reduce the challenge hash mod n and reject proofs with e >= n, so the
copy used by the BIP-375 validator matches the current BIP-374
reference.
---
 bip-0375/deps/dleq.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/bip-0375/deps/dleq.py b/bip-0375/deps/dleq.py
index 81540356..f1060ee9 100644
--- a/bip-0375/deps/dleq.py
+++ b/bip-0375/deps/dleq.py
@@ -32,7 +32,7 @@ def dleq_challenge(
             + m,
         ),
         "big",
-    )
+    ) % GE.ORDER
 
 
 def dleq_generate_proof(
@@ -72,6 +72,8 @@ def dleq_verify_proof(
         return False
     assert len(proof) == 64
     e = int.from_bytes(proof[:32], "big")
+    if e >= GE.ORDER:
+        return False
     s = int.from_bytes(proof[32:], "big")
     if s >= GE.ORDER:
         return False