From dd6d60fc1a14d4569d0f76919e40710e2cec6127 Mon Sep 17 00:00:00 2001
From: sergey-shandar <sergey-shandar@users.noreply.github.com>
Date: Wed, 17 Jul 2024 10:02:49 -0700
Subject: [PATCH] hmac

---
 blockset-lib/src/hmac.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/blockset-lib/src/hmac.rs b/blockset-lib/src/hmac.rs
index 0d1a47f5..948a654e 100644
--- a/blockset-lib/src/hmac.rs
+++ b/blockset-lib/src/hmac.rs
@@ -19,7 +19,11 @@ const fn sha256(data: U512) -> U256 {
     state.end(u512x::ZERO, 0)
 }
 
+const fn op(key: U256, pad: U256, data: U256) -> U256 {
+    sha256([u256x::bitor(&key, &pad), data])
+}
+
 pub const fn hmac(key: U256, msg: U256) -> U256 {
-    let hash = sha256([u256x::bitor(&key, &I_PAD), msg]);
-    sha256([u256x::bitor(&key, &O_PAD), hash])
+    let hash = op(key, I_PAD, msg);
+    op(key, O_PAD, hash)
 }