From 5a4b174b940f7c7b18936945be36eb1be025d36d Mon Sep 17 00:00:00 2001
From: Michael de Hoog <michael.dehoog@coinbase.com>
Date: Wed, 11 Dec 2024 18:59:50 -1000
Subject: [PATCH] Comment about public key

---
 contracts/src/SystemConfigGlobal.sol | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/contracts/src/SystemConfigGlobal.sol b/contracts/src/SystemConfigGlobal.sol
index 737a99d..01bf099 100644
--- a/contracts/src/SystemConfigGlobal.sol
+++ b/contracts/src/SystemConfigGlobal.sol
@@ -59,6 +59,8 @@ contract SystemConfigGlobal is OwnableUpgradeable, ISemver, NitroValidator {
 
         require(ptrs.timestamp + MAX_AGE > block.timestamp, "attestation too old");
 
+        // The publicKey is encoded in the form specified in section 4.3.6 of ANSI X9.62, which is a
+        // 0x04 byte followed by the x and y coordinates of the public key. We ignore the first byte.
         bytes32 publicKeyHash = attestationTbs.keccak(ptrs.publicKey.start() + 1, ptrs.publicKey.length() - 1);
         address enclaveAddress = address(uint160(uint256(publicKeyHash)));
         validSigners[enclaveAddress] = true;