diff --git a/programs/x509/cert_app.c b/programs/x509/cert_app.c
new file mode 100644
index 0000000..38fbd51
--- /dev/null
+++ b/programs/x509/cert_app.c
@@ -0,0 +1,515 @@
+/*
+ *  Certificate reading application
+ *
+ *  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_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#define mbedtls_time            time
+#define mbedtls_time_t          time_t
+#define mbedtls_fprintf         fprintf
+#define mbedtls_printf          printf
+#define mbedtls_exit            exit
+#define MBEDTLS_EXIT_SUCCESS    EXIT_SUCCESS
+#define MBEDTLS_EXIT_FAILURE    EXIT_FAILURE
+#endif /* MBEDTLS_PLATFORM_C */
+
+#if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||  \
+    !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_CLI_C) || \
+    !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_RSA_C) ||         \
+    !defined(MBEDTLS_X509_CRT_PARSE_C) || !defined(MBEDTLS_FS_IO) ||  \
+    !defined(MBEDTLS_CTR_DRBG_C)
+int main( void )
+{
+    mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
+           "MBEDTLS_SSL_TLS_C and/or MBEDTLS_SSL_CLI_C and/or "
+           "MBEDTLS_NET_C and/or MBEDTLS_RSA_C and/or "
+           "MBEDTLS_X509_CRT_PARSE_C and/or MBEDTLS_FS_IO and/or "
+           "MBEDTLS_CTR_DRBG_C not defined.\n");
+    return( 0 );
+}
+#else
+
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/net_sockets.h"
+#include "mbedtls/ssl.h"
+#include "mbedtls/x509.h"
+#include "mbedtls/debug.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MODE_NONE               0
+#define MODE_FILE               1
+#define MODE_SSL                2
+
+#define DFL_MODE                MODE_NONE
+#define DFL_FILENAME            "cert.crt"
+#define DFL_CA_FILE             ""
+#define DFL_CRL_FILE            ""
+#define DFL_CA_PATH             ""
+#define DFL_SERVER_NAME         "localhost"
+#define DFL_SERVER_PORT         "4433"
+#define DFL_DEBUG_LEVEL         0
+#define DFL_PERMISSIVE          0
+
+#define USAGE_IO \
+    "    ca_file=%%s          The single file containing the top-level CA(s) you fully trust\n" \
+    "                        default: \"\" (none)\n" \
+    "    crl_file=%%s         The single CRL file you want to use\n" \
+    "                        default: \"\" (none)\n" \
+    "    ca_path=%%s          The path containing the top-level CA(s) you fully trust\n" \
+    "                        default: \"\" (none) (overrides ca_file)\n"
+
+#define USAGE \
+    "\n usage: cert_app param=<>...\n"                  \
+    "\n acceptable parameters:\n"                       \
+    "    mode=file|ssl       default: none\n"           \
+    "    filename=%%s         default: cert.crt\n"      \
+    USAGE_IO                                            \
+    "    server_name=%%s      default: localhost\n"     \
+    "    server_port=%%d      default: 4433\n"          \
+    "    debug_level=%%d      default: 0 (disabled)\n"  \
+    "    permissive=%%d       default: 0 (disabled)\n"  \
+    "\n"
+
+#if defined(MBEDTLS_CHECK_PARAMS)
+#define mbedtls_exit            exit
+void mbedtls_param_failed( const char *failure_condition,
+                           const char *file,
+                           int line )
+{
+    mbedtls_printf( "%s:%i: Input param failed - %s\n",
+                    file, line, failure_condition );
+    mbedtls_exit( MBEDTLS_EXIT_FAILURE );
+}
+#endif
+
+/*
+ * global options
+ */
+struct options
+{
+    int mode;                   /* the mode to run the application in   */
+    const char *filename;       /* filename of the certificate file     */
+    const char *ca_file;        /* the file with the CA certificate(s)  */
+    const char *crl_file;       /* the file with the CRL to use         */
+    const char *ca_path;        /* the path with the CA certificate(s) reside */
+    const char *server_name;    /* hostname of the server (client only) */
+    const char *server_port;    /* port on which the ssl service runs   */
+    int debug_level;            /* level of debugging                   */
+    int permissive;             /* permissive parsing                   */
+} opt;
+
+static void my_debug( void *ctx, int level,
+                      const char *file, int line,
+                      const char *str )
+{
+    ((void) level);
+
+    mbedtls_fprintf( (FILE *) ctx, "%s:%04d: %s", file, line, str );
+    fflush(  (FILE *) ctx  );
+}
+
+static int my_verify( void *data, mbedtls_x509_crt *crt, int depth, uint32_t *flags )
+{
+    char buf[1024];
+    ((void) data);
+
+    mbedtls_printf( "\nVerify requested for (Depth %d):\n", depth );
+    mbedtls_x509_crt_info( buf, sizeof( buf ) - 1, "", crt );
+    mbedtls_printf( "%s", buf );
+
+    if ( ( *flags ) == 0 )
+        mbedtls_printf( "  This certificate has no flags\n" );
+    else
+    {
+        mbedtls_x509_crt_verify_info( buf, sizeof( buf ), "  ! ", *flags );
+        mbedtls_printf( "%s\n", buf );
+    }
+
+    return( 0 );
+}
+
+int main( int argc, char *argv[] )
+{
+    int ret = 1;
+    int exit_code = MBEDTLS_EXIT_FAILURE;
+    mbedtls_net_context server_fd;
+    unsigned char buf[1024];
+    mbedtls_entropy_context entropy;
+    mbedtls_ctr_drbg_context ctr_drbg;
+    mbedtls_ssl_context ssl;
+    mbedtls_ssl_config conf;
+    mbedtls_x509_crt cacert;
+    mbedtls_x509_crl cacrl;
+    int i, j;
+    uint32_t flags;
+    int verify = 0;
+    char *p, *q;
+    const char *pers = "cert_app";
+
+    /*
+     * Set to sane values
+     */
+    mbedtls_net_init( &server_fd );
+    mbedtls_ctr_drbg_init( &ctr_drbg );
+    mbedtls_ssl_init( &ssl );
+    mbedtls_ssl_config_init( &conf );
+    mbedtls_x509_crt_init( &cacert );
+#if defined(MBEDTLS_X509_CRL_PARSE_C)
+    mbedtls_x509_crl_init( &cacrl );
+#else
+    /* Zeroize structure as CRL parsing is not supported and we have to pass
+       it to the verify function */
+    memset( &cacrl, 0, sizeof(mbedtls_x509_crl) );
+#endif
+
+    if( argc == 0 )
+    {
+    usage:
+        mbedtls_printf( USAGE );
+        goto exit;
+    }
+
+    opt.mode                = DFL_MODE;
+    opt.filename            = DFL_FILENAME;
+    opt.ca_file             = DFL_CA_FILE;
+    opt.crl_file            = DFL_CRL_FILE;
+    opt.ca_path             = DFL_CA_PATH;
+    opt.server_name         = DFL_SERVER_NAME;
+    opt.server_port         = DFL_SERVER_PORT;
+    opt.debug_level         = DFL_DEBUG_LEVEL;
+    opt.permissive          = DFL_PERMISSIVE;
+
+    for( i = 1; i < argc; i++ )
+    {
+        p = argv[i];
+        if( ( q = strchr( p, '=' ) ) == NULL )
+            goto usage;
+        *q++ = '\0';
+
+        for( j = 0; p + j < q; j++ )
+        {
+            if( argv[i][j] >= 'A' && argv[i][j] <= 'Z' )
+                argv[i][j] |= 0x20;
+        }
+
+        if( strcmp( p, "mode" ) == 0 )
+        {
+            if( strcmp( q, "file" ) == 0 )
+                opt.mode = MODE_FILE;
+            else if( strcmp( q, "ssl" ) == 0 )
+                opt.mode = MODE_SSL;
+            else
+                goto usage;
+        }
+        else if( strcmp( p, "filename" ) == 0 )
+            opt.filename = q;
+        else if( strcmp( p, "ca_file" ) == 0 )
+            opt.ca_file = q;
+        else if( strcmp( p, "crl_file" ) == 0 )
+            opt.crl_file = q;
+        else if( strcmp( p, "ca_path" ) == 0 )
+            opt.ca_path = q;
+        else if( strcmp( p, "server_name" ) == 0 )
+            opt.server_name = q;
+        else if( strcmp( p, "server_port" ) == 0 )
+            opt.server_port = q;
+        else if( strcmp( p, "debug_level" ) == 0 )
+        {
+            opt.debug_level = atoi( q );
+            if( opt.debug_level < 0 || opt.debug_level > 65535 )
+                goto usage;
+        }
+        else if( strcmp( p, "permissive" ) == 0 )
+        {
+            opt.permissive = atoi( q );
+            if( opt.permissive < 0 || opt.permissive > 1 )
+                goto usage;
+        }
+        else
+            goto usage;
+    }
+
+    /*
+     * 1.1. Load the trusted CA
+     */
+    mbedtls_printf( "  . Loading the CA root certificate ..." );
+    fflush( stdout );
+
+    if( strlen( opt.ca_path ) )
+    {
+        if( ( ret = mbedtls_x509_crt_parse_path( &cacert, opt.ca_path ) ) < 0 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse_path returned -0x%x\n\n", -ret );
+            goto exit;
+        }
+
+        verify = 1;
+    }
+    else if( strlen( opt.ca_file ) )
+    {
+        if( ( ret = mbedtls_x509_crt_parse_file( &cacert, opt.ca_file ) ) < 0 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse_file returned -0x%x\n\n", -ret );
+            goto exit;
+        }
+
+        verify = 1;
+    }
+
+    mbedtls_printf( " ok (%d skipped)\n", ret );
+
+#if defined(MBEDTLS_X509_CRL_PARSE_C)
+    if( strlen( opt.crl_file ) )
+    {
+        if( ( ret = mbedtls_x509_crl_parse_file( &cacrl, opt.crl_file ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crl_parse returned -0x%x\n\n", -ret );
+            goto exit;
+        }
+
+        verify = 1;
+    }
+#endif
+
+    if( opt.mode == MODE_FILE )
+    {
+        mbedtls_x509_crt crt;
+        mbedtls_x509_crt *cur = &crt;
+        mbedtls_x509_crt_init( &crt );
+
+        /*
+         * 1.1. Load the certificate(s)
+         */
+        mbedtls_printf( "\n  . Loading the certificate(s) ..." );
+        fflush( stdout );
+
+        ret = mbedtls_x509_crt_parse_file( &crt, opt.filename );
+
+        if( ret < 0 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse_file returned %d\n\n", ret );
+            mbedtls_x509_crt_free( &crt );
+            goto exit;
+        }
+
+        if( opt.permissive == 0 && ret > 0 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_parse failed to parse %d certificates\n\n", ret );
+            mbedtls_x509_crt_free( &crt );
+            goto exit;
+        }
+
+        mbedtls_printf( " ok\n" );
+
+        /*
+         * 1.2 Print the certificate(s)
+         */
+        while( cur != NULL )
+        {
+            mbedtls_printf( "  . Peer certificate information    ...\n" );
+            ret = mbedtls_x509_crt_info( (char *) buf, sizeof( buf ) - 1, "      ",
+                                 cur );
+            if( ret == -1 )
+            {
+                mbedtls_printf( " failed\n  !  mbedtls_x509_crt_info returned %d\n\n", ret );
+                mbedtls_x509_crt_free( &crt );
+                goto exit;
+            }
+
+            mbedtls_printf( "%s\n", buf );
+
+            cur = cur->next;
+        }
+
+        /*
+         * 1.3 Verify the certificate
+         */
+        if( verify )
+        {
+            mbedtls_printf( "  . Verifying X.509 certificate..." );
+
+            if( ( ret = mbedtls_x509_crt_verify( &crt, &cacert, &cacrl, NULL, &flags,
+                                         my_verify, NULL ) ) != 0 )
+            {
+                char vrfy_buf[512];
+
+                mbedtls_printf( " failed\n" );
+
+                mbedtls_x509_crt_verify_info( vrfy_buf, sizeof( vrfy_buf ), "  ! ", flags );
+
+                mbedtls_printf( "%s\n", vrfy_buf );
+            }
+            else
+                mbedtls_printf( " ok\n" );
+        }
+
+        mbedtls_x509_crt_free( &crt );
+    }
+    else if( opt.mode == MODE_SSL )
+    {
+        /*
+         * 1. Initialize the RNG and the session data
+         */
+        mbedtls_printf( "\n  . Seeding the random number generator..." );
+        fflush( stdout );
+
+        mbedtls_entropy_init( &entropy );
+        if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
+                                   (const unsigned char *) pers,
+                                   strlen( pers ) ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret );
+            goto ssl_exit;
+        }
+
+        mbedtls_printf( " ok\n" );
+
+#if defined(MBEDTLS_DEBUG_C)
+        mbedtls_debug_set_threshold( opt.debug_level );
+#endif
+
+        /*
+         * 2. Start the connection
+         */
+        mbedtls_printf( "  . SSL connection to tcp/%s/%s...", opt.server_name,
+                                                              opt.server_port );
+        fflush( stdout );
+
+        if( ( ret = mbedtls_net_connect( &server_fd, opt.server_name,
+                                 opt.server_port, MBEDTLS_NET_PROTO_TCP ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_net_connect returned %d\n\n", ret );
+            goto ssl_exit;
+        }
+
+        /*
+         * 3. Setup stuff
+         */
+        if( ( ret = mbedtls_ssl_config_defaults( &conf,
+                        MBEDTLS_SSL_IS_CLIENT,
+                        MBEDTLS_SSL_TRANSPORT_STREAM,
+                        MBEDTLS_SSL_PRESET_DEFAULT ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ssl_config_defaults returned %d\n\n", ret );
+            goto exit;
+        }
+
+        if( verify )
+        {
+            mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_REQUIRED );
+            mbedtls_ssl_conf_ca_chain( &conf, &cacert, NULL );
+            mbedtls_ssl_conf_verify( &conf, my_verify, NULL );
+        }
+        else
+            mbedtls_ssl_conf_authmode( &conf, MBEDTLS_SSL_VERIFY_NONE );
+
+        mbedtls_ssl_conf_rng( &conf, mbedtls_ctr_drbg_random, &ctr_drbg );
+        mbedtls_ssl_conf_dbg( &conf, my_debug, stdout );
+
+        if( ( ret = mbedtls_ssl_setup( &ssl, &conf ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ssl_setup returned %d\n\n", ret );
+            goto ssl_exit;
+        }
+
+        if( ( ret = mbedtls_ssl_set_hostname( &ssl, opt.server_name ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ssl_set_hostname returned %d\n\n", ret );
+            goto ssl_exit;
+        }
+
+        mbedtls_ssl_set_bio( &ssl, &server_fd, mbedtls_net_send, mbedtls_net_recv, NULL );
+
+        /*
+         * 4. Handshake
+         */
+        while( ( ret = mbedtls_ssl_handshake( &ssl ) ) != 0 )
+        {
+            if( ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE )
+            {
+                mbedtls_printf( " failed\n  ! mbedtls_ssl_handshake returned %d\n\n", ret );
+                goto ssl_exit;
+            }
+        }
+
+        mbedtls_printf( " ok\n" );
+
+        /*
+         * 5. Print the certificate
+         */
+#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
+        mbedtls_printf( "  . Peer certificate information    ... skipped\n" );
+#else
+        mbedtls_printf( "  . Peer certificate information    ...\n" );
+        ret = mbedtls_x509_crt_info( (char *) buf, sizeof( buf ) - 1, "      ",
+                                     mbedtls_ssl_get_peer_cert( &ssl ) );
+        if( ret == -1 )
+        {
+            mbedtls_printf( " failed\n  !  mbedtls_x509_crt_info returned %d\n\n", ret );
+            goto ssl_exit;
+        }
+
+        mbedtls_printf( "%s\n", buf );
+#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
+
+        mbedtls_ssl_close_notify( &ssl );
+
+ssl_exit:
+        mbedtls_ssl_free( &ssl );
+        mbedtls_ssl_config_free( &conf );
+    }
+    else
+        goto usage;
+
+    exit_code = MBEDTLS_EXIT_SUCCESS;
+
+exit:
+
+    mbedtls_net_free( &server_fd );
+    mbedtls_x509_crt_free( &cacert );
+#if defined(MBEDTLS_X509_CRL_PARSE_C)
+    mbedtls_x509_crl_free( &cacrl );
+#endif
+    mbedtls_ctr_drbg_free( &ctr_drbg );
+    mbedtls_entropy_free( &entropy );
+
+#if defined(_WIN32)
+    mbedtls_printf( "  + Press Enter to exit this program.\n" );
+    fflush( stdout ); getchar();
+#endif
+
+    return( exit_code );
+}
+#endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_SSL_TLS_C &&
+          MBEDTLS_SSL_CLI_C && MBEDTLS_NET_C && MBEDTLS_RSA_C &&
+          MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */