From 755ff0e6853fbc568abb0414da21991fbabc2411 Mon Sep 17 00:00:00 2001
From: Janos Follath <janos.follath@arm.com>
Date: Tue, 7 Feb 2023 15:27:44 +0000
Subject: [PATCH] Add corner case to mod_p521 tests

Signed-off-by: Janos Follath <janos.follath@arm.com>
Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
---
 scripts/mbedtls_dev/ecp.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/scripts/mbedtls_dev/ecp.py b/scripts/mbedtls_dev/ecp.py
index e0fb00035..fa70dedb5 100644
--- a/scripts/mbedtls_dev/ecp.py
+++ b/scripts/mbedtls_dev/ecp.py
@@ -91,6 +91,13 @@ class EcpP521R1Raw(bignum_common.ModOperationCommon,
     input_values = [
         "0", "1",
 
+        # Corner case: maximum canonical P521 multiplication result
+        ("0003ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
+         "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
+         "fffff800"
+         "0000000000000000000000000000000000000000000000000000000000000000"
+         "0000000000000000000000000000000000000000000000000000000000000004"),
+
         # Test case for overflow during addition
         ("0001efffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"
          "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"