From 53c8abfd80b3d131790f515a3d31ba5d3beeb731 Mon Sep 17 00:00:00 2001
From: Davide Beatrici <davidebeatrici@gmail.com>
Date: Thu, 27 Sep 2018 20:28:48 +0200
Subject: [PATCH] Encrypt.c: fix MdProcess()'s HMAC implementation

---
 src/Mayaqua/Encrypt.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Mayaqua/Encrypt.c b/src/Mayaqua/Encrypt.c
index 249ab5ab..ca157a22 100644
--- a/src/Mayaqua/Encrypt.c
+++ b/src/Mayaqua/Encrypt.c
@@ -461,6 +461,13 @@ UINT MdProcess(MD *md, void *dest, void *src, UINT size)
 
 	if (md->IsHMac)
 	{
+		// WARNING: Do not remove the call to HMAC_Init_ex(), it's required even if the context is initialized by SetMdKey()!
+		if (HMAC_Init_ex(md->Ctx, NULL, 0, NULL, NULL) == false)
+		{
+			Debug("MdProcess(): HMAC_Init_ex() failed with error: %s\n", OpenSSL_Error());
+			return 0;
+		}
+
 		if (HMAC_Update(md->Ctx, src, size) == false)
 		{
 			Debug("MdProcess(): HMAC_Update() failed with error: %s\n", OpenSSL_Error());