diff --git a/src/shared/Auth/Hmac.cpp b/src/shared/Auth/Hmac.cpp
new file mode 100644
index 0000000..32e94fb
--- /dev/null
+++ b/src/shared/Auth/Hmac.cpp
@@ -0,0 +1,56 @@
+/* 
+ * Copyright (C) 2005-2008 MaNGOS <http://www.mangosproject.org/>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "Auth/Hmac.h"
+#include "BigNumber.h"
+
+HmacHash::HmacHash()
+{
+    uint8 temp[SEED_KEY_SIZE] = { 0x38, 0xA7, 0x83, 0x15, 0xF8, 0x92, 0x25, 0x30, 0x71, 0x98, 0x67, 0xB1, 0x8C, 0x4, 0xE2, 0xAA };
+    memcpy(&m_key, &temp, SEED_KEY_SIZE);
+    HMAC_CTX_init(&m_ctx);
+    HMAC_Init_ex(&m_ctx, &m_key, SEED_KEY_SIZE, EVP_sha1(), NULL);
+}
+
+HmacHash::~HmacHash()
+{
+    memset(&m_key, 0x00, SEED_KEY_SIZE);
+    HMAC_CTX_cleanup(&m_ctx);
+}
+
+void HmacHash::UpdateBigNumber(BigNumber *bn)
+{
+    UpdateData(bn->AsByteArray(), bn->GetNumBytes());
+}
+
+void HmacHash::UpdateData(const uint8 *data, int length)
+{
+    HMAC_Update(&m_ctx, data, length);
+}
+
+void HmacHash::Initialize()
+{
+    HMAC_Init_ex(&m_ctx, &m_key, SEED_KEY_SIZE, EVP_sha1(), NULL);
+}
+
+void HmacHash::Finalize()
+{
+    unsigned int length = 0;
+    HMAC_Final(&m_ctx, m_digest, &length);
+    ASSERT(length == SHA_DIGEST_LENGTH)
+}
diff --git a/src/shared/Auth/Hmac.h b/src/shared/Auth/Hmac.h
new file mode 100644
index 0000000..df7574a
--- /dev/null
+++ b/src/shared/Auth/Hmac.h
@@ -0,0 +1,46 @@
+/* 
+ * Copyright (C) 2005-2008 MaNGOS <http://www.mangosproject.org/>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _AUTH_HMAC_H
+#define _AUTH_HMAC_H
+
+#include "Common.h"
+#include <openssl/hmac.h>
+#include <openssl/sha.h>
+
+class BigNumber;
+
+#define SEED_KEY_SIZE 16
+
+class HmacHash
+{
+    public:
+        HmacHash();
+        ~HmacHash();
+        void UpdateBigNumber(BigNumber *bn);
+        void UpdateData(const uint8 *data, int length);
+        void Initialize();
+        void Finalize();
+        uint8 *GetDigest() { return m_digest; };
+        int GetLength() { return SHA_DIGEST_LENGTH; };
+    private:
+        HMAC_CTX m_ctx;
+        uint8 m_key[SEED_KEY_SIZE];
+        uint8 m_digest[SHA_DIGEST_LENGTH];
+};
+#endif