diff --git a/library/debug.c b/library/debug.c
new file mode 100644
index 0000000..0c46c06
--- /dev/null
+++ b/library/debug.c
@@ -0,0 +1,438 @@
+/*
+ *  Debugging routines
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *  This file is part of mbed TLS (https://tls.mbed.org)
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_DEBUG_C)
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdlib.h>
+#define mbedtls_calloc      calloc
+#define mbedtls_free        free
+#define mbedtls_time_t      time_t
+#define mbedtls_snprintf    snprintf
+#define mbedtls_vsnprintf   vsnprintf
+#endif
+
+#include "mbedtls/debug.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
+#define inline __inline
+#endif
+
+#define DEBUG_BUF_SIZE      512
+
+static int debug_threshold = 0;
+
+void mbedtls_debug_set_threshold( int threshold )
+{
+    debug_threshold = threshold;
+}
+
+/*
+ * All calls to f_dbg must be made via this function
+ */
+static inline void debug_send_line( const mbedtls_ssl_context *ssl, int level,
+                                    const char *file, int line,
+                                    const char *str )
+{
+    /*
+     * If in a threaded environment, we need a thread identifier.
+     * Since there is no portable way to get one, use the address of the ssl
+     * context instead, as it shouldn't be shared between threads.
+     */
+#if defined(MBEDTLS_THREADING_C)
+    char idstr[20 + DEBUG_BUF_SIZE]; /* 0x + 16 nibbles + ': ' */
+    mbedtls_snprintf( idstr, sizeof( idstr ), "%p: %s", (void*)ssl, str );
+    ssl->conf->f_dbg( ssl->conf->p_dbg, level, file, line, idstr );
+#else
+    ssl->conf->f_dbg( ssl->conf->p_dbg, level, file, line, str );
+#endif
+}
+
+void mbedtls_debug_print_msg( const mbedtls_ssl_context *ssl, int level,
+                              const char *file, int line,
+                              const char *format, ... )
+{
+    va_list argp;
+    char str[DEBUG_BUF_SIZE];
+    int ret;
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    va_start( argp, format );
+    ret = mbedtls_vsnprintf( str, DEBUG_BUF_SIZE, format, argp );
+    va_end( argp );
+
+    if( ret >= 0 && ret < DEBUG_BUF_SIZE - 1 )
+    {
+        str[ret]     = '\n';
+        str[ret + 1] = '\0';
+    }
+
+    debug_send_line( ssl, level, file, line, str );
+}
+
+void mbedtls_debug_print_ret( const mbedtls_ssl_context *ssl, int level,
+                      const char *file, int line,
+                      const char *text, int ret )
+{
+    char str[DEBUG_BUF_SIZE];
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    /*
+     * With non-blocking I/O and examples that just retry immediately,
+     * the logs would be quickly flooded with WANT_READ, so ignore that.
+     * Don't ignore WANT_WRITE however, since is is usually rare.
+     */
+    if( ret == MBEDTLS_ERR_SSL_WANT_READ )
+        return;
+
+    mbedtls_snprintf( str, sizeof( str ), "%s() returned %d (-0x%04x)\n",
+              text, ret, -ret );
+
+    debug_send_line( ssl, level, file, line, str );
+}
+
+void mbedtls_debug_print_buf( const mbedtls_ssl_context *ssl, int level,
+                      const char *file, int line, const char *text,
+                      const unsigned char *buf, size_t len )
+{
+    char str[DEBUG_BUF_SIZE];
+    char txt[17];
+    size_t i, idx = 0;
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    mbedtls_snprintf( str + idx, sizeof( str ) - idx, "dumping '%s' (%u bytes)\n",
+              text, (unsigned int) len );
+
+    debug_send_line( ssl, level, file, line, str );
+
+    idx = 0;
+    memset( txt, 0, sizeof( txt ) );
+    for( i = 0; i < len; i++ )
+    {
+        if( i >= 4096 )
+            break;
+
+        if( i % 16 == 0 )
+        {
+            if( i > 0 )
+            {
+                mbedtls_snprintf( str + idx, sizeof( str ) - idx, "  %s\n", txt );
+                debug_send_line( ssl, level, file, line, str );
+
+                idx = 0;
+                memset( txt, 0, sizeof( txt ) );
+            }
+
+            idx += mbedtls_snprintf( str + idx, sizeof( str ) - idx, "%04x: ",
+                             (unsigned int) i );
+
+        }
+
+        idx += mbedtls_snprintf( str + idx, sizeof( str ) - idx, " %02x",
+                         (unsigned int) buf[i] );
+        txt[i % 16] = ( buf[i] > 31 && buf[i] < 127 ) ? buf[i] : '.' ;
+    }
+
+    if( len > 0 )
+    {
+        for( /* i = i */; i % 16 != 0; i++ )
+            idx += mbedtls_snprintf( str + idx, sizeof( str ) - idx, "   " );
+
+        mbedtls_snprintf( str + idx, sizeof( str ) - idx, "  %s\n", txt );
+        debug_send_line( ssl, level, file, line, str );
+    }
+}
+
+#if defined(MBEDTLS_ECP_C)
+void mbedtls_debug_print_ecp( const mbedtls_ssl_context *ssl, int level,
+                      const char *file, int line,
+                      const char *text, const mbedtls_ecp_point *X )
+{
+    char str[DEBUG_BUF_SIZE];
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    mbedtls_snprintf( str, sizeof( str ), "%s(X)", text );
+    mbedtls_debug_print_mpi( ssl, level, file, line, str, &X->X );
+
+    mbedtls_snprintf( str, sizeof( str ), "%s(Y)", text );
+    mbedtls_debug_print_mpi( ssl, level, file, line, str, &X->Y );
+}
+#endif /* MBEDTLS_ECP_C */
+
+#if defined(MBEDTLS_BIGNUM_C)
+void mbedtls_debug_print_mpi( const mbedtls_ssl_context *ssl, int level,
+                      const char *file, int line,
+                      const char *text, const mbedtls_mpi *X )
+{
+    char str[DEBUG_BUF_SIZE];
+    int j, k, zeros = 1;
+    size_t i, n, idx = 0;
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        NULL == X                ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    for( n = X->n - 1; n > 0; n-- )
+        if( X->p[n] != 0 )
+            break;
+
+    for( j = ( sizeof(mbedtls_mpi_uint) << 3 ) - 1; j >= 0; j-- )
+        if( ( ( X->p[n] >> j ) & 1 ) != 0 )
+            break;
+
+    mbedtls_snprintf( str + idx, sizeof( str ) - idx, "value of '%s' (%d bits) is:\n",
+              text, (int) ( ( n * ( sizeof(mbedtls_mpi_uint) << 3 ) ) + j + 1 ) );
+
+    debug_send_line( ssl, level, file, line, str );
+
+    idx = 0;
+    for( i = n + 1, j = 0; i > 0; i-- )
+    {
+        if( zeros && X->p[i - 1] == 0 )
+            continue;
+
+        for( k = sizeof( mbedtls_mpi_uint ) - 1; k >= 0; k-- )
+        {
+            if( zeros && ( ( X->p[i - 1] >> ( k << 3 ) ) & 0xFF ) == 0 )
+                continue;
+            else
+                zeros = 0;
+
+            if( j % 16 == 0 )
+            {
+                if( j > 0 )
+                {
+                    mbedtls_snprintf( str + idx, sizeof( str ) - idx, "\n" );
+                    debug_send_line( ssl, level, file, line, str );
+                    idx = 0;
+                }
+            }
+
+            idx += mbedtls_snprintf( str + idx, sizeof( str ) - idx, " %02x", (unsigned int)
+                             ( X->p[i - 1] >> ( k << 3 ) ) & 0xFF );
+
+            j++;
+        }
+
+    }
+
+    if( zeros == 1 )
+        idx += mbedtls_snprintf( str + idx, sizeof( str ) - idx, " 00" );
+
+    mbedtls_snprintf( str + idx, sizeof( str ) - idx, "\n" );
+    debug_send_line( ssl, level, file, line, str );
+}
+#endif /* MBEDTLS_BIGNUM_C */
+
+#if defined(MBEDTLS_X509_CRT_PARSE_C)
+static void debug_print_pk( const mbedtls_ssl_context *ssl, int level,
+                            const char *file, int line,
+                            const char *text, const mbedtls_pk_context *pk )
+{
+    size_t i;
+    mbedtls_pk_debug_item items[MBEDTLS_PK_DEBUG_MAX_ITEMS];
+    char name[16];
+
+    memset( items, 0, sizeof( items ) );
+
+    if( mbedtls_pk_debug( pk, items ) != 0 )
+    {
+        debug_send_line( ssl, level, file, line,
+                          "invalid PK context\n" );
+        return;
+    }
+
+    for( i = 0; i < MBEDTLS_PK_DEBUG_MAX_ITEMS; i++ )
+    {
+        if( items[i].type == MBEDTLS_PK_DEBUG_NONE )
+            return;
+
+        mbedtls_snprintf( name, sizeof( name ), "%s%s", text, items[i].name );
+        name[sizeof( name ) - 1] = '\0';
+
+        if( items[i].type == MBEDTLS_PK_DEBUG_MPI )
+            mbedtls_debug_print_mpi( ssl, level, file, line, name, items[i].value );
+        else
+#if defined(MBEDTLS_ECP_C)
+        if( items[i].type == MBEDTLS_PK_DEBUG_ECP )
+            mbedtls_debug_print_ecp( ssl, level, file, line, name, items[i].value );
+        else
+#endif
+            debug_send_line( ssl, level, file, line,
+                              "should not happen\n" );
+    }
+}
+
+static void debug_print_line_by_line( const mbedtls_ssl_context *ssl, int level,
+                                      const char *file, int line, const char *text )
+{
+    char str[DEBUG_BUF_SIZE];
+    const char *start, *cur;
+
+    start = text;
+    for( cur = text; *cur != '\0'; cur++ )
+    {
+        if( *cur == '\n' )
+        {
+            size_t len = cur - start + 1;
+            if( len > DEBUG_BUF_SIZE - 1 )
+                len = DEBUG_BUF_SIZE - 1;
+
+            memcpy( str, start, len );
+            str[len] = '\0';
+
+            debug_send_line( ssl, level, file, line, str );
+
+            start = cur + 1;
+        }
+    }
+}
+
+void mbedtls_debug_print_crt( const mbedtls_ssl_context *ssl, int level,
+                      const char *file, int line,
+                      const char *text, const mbedtls_x509_crt *crt )
+{
+    char str[DEBUG_BUF_SIZE];
+    int i = 0;
+
+    if( NULL == ssl              ||
+        NULL == ssl->conf        ||
+        NULL == ssl->conf->f_dbg ||
+        NULL == crt              ||
+        level > debug_threshold )
+    {
+        return;
+    }
+
+    while( crt != NULL )
+    {
+        char buf[1024];
+
+        mbedtls_snprintf( str, sizeof( str ), "%s #%d:\n", text, ++i );
+        debug_send_line( ssl, level, file, line, str );
+
+        mbedtls_x509_crt_info( buf, sizeof( buf ) - 1, "", crt );
+        debug_print_line_by_line( ssl, level, file, line, buf );
+
+        debug_print_pk( ssl, level, file, line, "crt->", &crt->pk );
+
+        crt = crt->next;
+    }
+}
+#endif /* MBEDTLS_X509_CRT_PARSE_C */
+
+#if defined(MBEDTLS_ECDH_C)
+static void mbedtls_debug_printf_ecdh_internal( const mbedtls_ssl_context *ssl,
+                                                int level, const char *file,
+                                                int line,
+                                                const mbedtls_ecdh_context *ecdh,
+                                                mbedtls_debug_ecdh_attr attr )
+{
+#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
+    const mbedtls_ecdh_context* ctx = ecdh;
+#else
+    const mbedtls_ecdh_context_mbed* ctx = &ecdh->ctx.mbed_ecdh;
+#endif
+
+    switch( attr )
+    {
+        case MBEDTLS_DEBUG_ECDH_Q:
+            mbedtls_debug_print_ecp( ssl, level, file, line, "ECDH: Q",
+                                     &ctx->Q );
+            break;
+        case MBEDTLS_DEBUG_ECDH_QP:
+            mbedtls_debug_print_ecp( ssl, level, file, line, "ECDH: Qp",
+                                     &ctx->Qp );
+            break;
+        case MBEDTLS_DEBUG_ECDH_Z:
+            mbedtls_debug_print_mpi( ssl, level, file, line, "ECDH: z",
+                                     &ctx->z );
+            break;
+        default:
+            break;
+    }
+}
+
+void mbedtls_debug_printf_ecdh( const mbedtls_ssl_context *ssl, int level,
+                                const char *file, int line,
+                                const mbedtls_ecdh_context *ecdh,
+                                mbedtls_debug_ecdh_attr attr )
+{
+#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
+    mbedtls_debug_printf_ecdh_internal( ssl, level, file, line, ecdh, attr );
+#else
+    switch( ecdh->var )
+    {
+        default:
+            mbedtls_debug_printf_ecdh_internal( ssl, level, file, line, ecdh,
+                                                attr );
+    }
+#endif
+}
+#endif /* MBEDTLS_ECDH_C */
+
+#endif /* MBEDTLS_DEBUG_C */