diff --git a/mcu/interface/driver/che/x509.h b/mcu/interface/driver/che/x509.h
new file mode 100644
index 0000000..d7df121
--- /dev/null
+++ b/mcu/interface/driver/che/x509.h
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2007, Cameron Rich
+ * 
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice, 
+ *   this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice, 
+ *   this list of conditions and the following disclaimer in the documentation 
+ *   and/or other materials provided with the distribution.
+ * * Neither the name of the axTLS project nor the names of its contributors 
+ *   may be used to endorse or promote products derived from this software 
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef __HEADER_X509_H__
+#define __HEADER_X509_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <time.h>
+#include "cust_chl_interface.h"
+#include "kal_public_api.h"
+#include "kal_public_defs.h"
+#include "ps_public_struct.h"
+
+#define malloc get_ctrl_buffer
+#define free   free_ctrl_buffer
+
+/**************************************************************************
+ * X509 declarations 
+ **************************************************************************/
+#define X509_OK                             0
+#define X509_NOT_OK                         -1
+#define X509_VFY_ERROR_NO_TRUSTED_CERT      -2
+#define X509_VFY_ERROR_BAD_SIGNATURE        -3      
+#define X509_VFY_ERROR_NOT_YET_VALID        -4
+#define X509_VFY_ERROR_EXPIRED              -5
+#define X509_VFY_ERROR_SELF_SIGNED          -6
+#define X509_VFY_ERROR_INVALID_CHAIN        -7
+#define X509_VFY_ERROR_UNSUPPORTED_DIGEST   -8
+#define X509_UNRECOGNISED_SIG_TYPE          -9
+#define X509_VFY_ERROR_NO_UNTRUSTED_CERT    -10
+#define X509_VFY_ERROR_GET_CA_DN            -11
+#define X509_VFY_ERROR_GET_CERT_DN          -12
+#define X509_VFY_ERROR_GET_TIME             -13
+#define X509_VFY_ERROR_GET_PUB_KEY          -14
+#define X509_VFY_ERROR_INOUT_NULL_PTR		-15
+/*
+ * The Distinguished Name
+ */
+#define X509_NUM_DN_TYPES                   3
+
+struct _x509_ctx
+{
+    char *ca_cert_dn[X509_NUM_DN_TYPES];
+    char *cert_dn[X509_NUM_DN_TYPES];
+    kal_uint32 not_before;
+    kal_uint32 not_after;
+	kal_uint8 *tbs;
+	kal_uint32 tbs_len;
+	t_cust_chl_asym_key key;
+    kal_uint8 *signature;
+    kal_uint16 sig_len;
+    kal_uint8 sig_type;
+    struct _x509_ctx *next;
+};
+
+typedef struct _x509_ctx X509_CTX;
+
+#define CONFIG_X509_MAX_CA_CERTS 150
+
+typedef struct 
+{
+    X509_CTX *cert[CONFIG_X509_MAX_CA_CERTS];
+} CA_CERT_CTX;
+
+int x509_new(const kal_uint8 *cert, int *len, X509_CTX **ctx);
+void x509_free(X509_CTX *x509_ctx);
+int x509_verify(const CA_CERT_CTX *ca_cert_ctx, const X509_CTX *cert);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif