From c27ebb79e95fcb36ce4dc1629ad54733f1324f97 Mon Sep 17 00:00:00 2001
From: enitrat <msaug@protonmail.com>
Date: Thu, 5 Sep 2024 13:44:42 +0200
Subject: [PATCH] fix: p256 verify output is a 32-bytes array

---
 crates/evm/src/precompiles/p256verify.cairo | 41 ++++++++++++++++++++-
 1 file changed, 39 insertions(+), 2 deletions(-)

diff --git a/crates/evm/src/precompiles/p256verify.cairo b/crates/evm/src/precompiles/p256verify.cairo
index 0105e53f3..bc7ae09be 100644
--- a/crates/evm/src/precompiles/p256verify.cairo
+++ b/crates/evm/src/precompiles/p256verify.cairo
@@ -9,6 +9,43 @@ use utils::helpers::{U256Trait, ToBytes, FromBytes};
 
 const P256VERIFY_PRECOMPILE_GAS_COST: u128 = 3450;
 
+const ONE_32_BYTES: [
+    u8
+    ; 32] = [
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x01
+];
+
 impl P256Verify of Precompile {
     #[inline(always)]
     fn address() -> EthAddress {
@@ -62,7 +99,7 @@ impl P256Verify of Precompile {
             return Result::Ok((gas, [].span()));
         }
 
-        return Result::Ok((gas, [1].span()));
+        return Result::Ok((gas, ONE_32_BYTES.span()));
     }
 }
 
@@ -105,7 +142,7 @@ mod tests {
 
         let (gas, result) = P256Verify::exec(calldata.span()).unwrap();
 
-        let result: u256 = result.from_be_bytes().unwrap();
+        let result: u256 = result.from_be_bytes().expect('p256verify_precompile_test');
         assert_eq!(result, 0x01);
         assert_eq!(gas, 3450);
     }