From aea6175f2fbba7f69aec1b6d6a31398c07c97efc Mon Sep 17 00:00:00 2001
From: Monica Moniot <mamoniot@protonmail.com>
Date: Tue, 15 Aug 2023 18:51:22 -0400
Subject: [PATCH] changed digest order

---
 src/p384.rs | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/p384.rs b/src/p384.rs
index 3c926d4..4a0af87 100644
--- a/src/p384.rs
+++ b/src/p384.rs
@@ -73,13 +73,14 @@ unsafe impl Sync for P384PublicKey {}
 fn create_digest(domain: &[u8], data: &[&[u8]]) -> [u8; SHA384_HASH_SIZE] {
     debug_assert!(domain.len() <= u16::MAX as usize);
     let mut hasher = SHA384::new();
-    if domain.len() > 0 {
-        hasher.update(&(domain.len() as u16).to_be_bytes());
-        hasher.update(domain);
-    }
     for msg in data {
         hasher.update(msg);
     }
+    // We hash the domain last to mitigate some of the weaknesses of merkle-damgard.
+    if domain.len() > 0 {
+        hasher.update(domain);
+        hasher.update(&(domain.len() as u16).to_be_bytes());
+    }
     hasher.finish()
 }