From 966e8bd6c15f3a5e7f5cb872b969dbc66f9d49e3 Mon Sep 17 00:00:00 2001
From: Vlad Stan <stan.v.vlad@gmail.com>
Date: Thu, 13 Nov 2025 12:02:10 +0200
Subject: [PATCH] fix: point multiplication

---
 helpers.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/helpers.py b/helpers.py
index 478c0e1..90c94bd 100644
--- a/helpers.py
+++ b/helpers.py
@@ -10,8 +10,11 @@ from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
 def get_shared_secret(privkey: str, pubkey: str):
     pk = coincurve.PublicKey(bytes.fromhex("02" + pubkey))
     sk = coincurve.PrivateKey(bytes.fromhex(privkey))
-    return sk.ecdh(pk.format())
+    shared_point = pk.multiply(sk.secret)
 
+    shared_point_bytes = shared_point.format(compressed=False)
+    x_coord = shared_point_bytes[1:33]
+    return x_coord
 
 def decrypt_message(encoded_message: str, encryption_key) -> str:
     encoded_data = encoded_message.split("?iv=")