Feature/mbedtls (#84)

* try to import mbedtls and build it * add stubs socket class * some boilterplate, read and write function implemented * more boilterplate / current error in handshake because no CA cert is setup * add something so skip ca verification, can ws curl https://google.com ! * cleanup / close implemented * tweak CMakefiles * typo in include * update readme * disable unittests
2019-06-01 17:41:48 -07:00
parent 977e8794ec
commit 57976cf613
1614 changed files with 441051 additions and 13 deletions
--- a/third_party/mbedtls/crypto/programs/test/CMakeLists.txt
+++ b/third_party/mbedtls/crypto/programs/test/CMakeLists.txt
@ -0,0 +1,25 @@
+set(libs
+    mbedcrypto
+)
+
+add_executable(selftest selftest.c)
+target_link_libraries(selftest ${libs})
+
+add_executable(benchmark benchmark.c)
+target_link_libraries(benchmark ${libs})
+
+if(TEST_CPP)
+    add_executable(cpp_dummy_build cpp_dummy_build.cpp)
+    target_link_libraries(cpp_dummy_build ${libs})
+endif()
+
+add_executable(zeroize zeroize.c)
+target_link_libraries(zeroize ${libs})
+
+add_executable(query_compile_time_config query_compile_time_config.c)
+target_sources(query_compile_time_config PUBLIC query_config.c)
+target_link_libraries(query_compile_time_config ${libs})
+
+install(TARGETS selftest benchmark query_compile_time_config
+        DESTINATION "bin"
+        PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE)
--- a/third_party/mbedtls/crypto/programs/test/benchmark.c
+++ b/third_party/mbedtls/crypto/programs/test/benchmark.c
--- a/third_party/mbedtls/crypto/programs/test/cpp_dummy_build.cpp
+++ b/third_party/mbedtls/crypto/programs/test/cpp_dummy_build.cpp
@ -0,0 +1,105 @@
+/*
+ *  This program is a dummy C++ program to ensure Mbed TLS library header files
+ *  can be included and built with a C++ compiler.
+ *
+ *  Copyright (C) 2018, 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
+
+#include "mbedtls/aes.h"
+#include "mbedtls/aesni.h"
+#include "mbedtls/arc4.h"
+#include "mbedtls/aria.h"
+#include "mbedtls/asn1.h"
+#include "mbedtls/asn1write.h"
+#include "mbedtls/base64.h"
+#include "mbedtls/bignum.h"
+#include "mbedtls/blowfish.h"
+#include "mbedtls/bn_mul.h"
+#include "mbedtls/camellia.h"
+#include "mbedtls/ccm.h"
+#include "mbedtls/certs.h"
+#include "mbedtls/chacha20.h"
+#include "mbedtls/chachapoly.h"
+#include "mbedtls/check_config.h"
+#include "mbedtls/cipher.h"
+#include "mbedtls/cipher_internal.h"
+#include "mbedtls/cmac.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/des.h"
+#include "mbedtls/dhm.h"
+#include "mbedtls/ecdh.h"
+#include "mbedtls/ecdsa.h"
+#include "mbedtls/ecjpake.h"
+#include "mbedtls/ecp.h"
+#include "mbedtls/ecp_internal.h"
+#include "mbedtls/entropy.h"
+#include "mbedtls/entropy_poll.h"
+#include "mbedtls/error.h"
+#include "mbedtls/gcm.h"
+#include "mbedtls/havege.h"
+#include "mbedtls/hkdf.h"
+#include "mbedtls/hmac_drbg.h"
+#include "mbedtls/md.h"
+#include "mbedtls/md2.h"
+#include "mbedtls/md4.h"
+#include "mbedtls/md5.h"
+#include "mbedtls/md_internal.h"
+#include "mbedtls/nist_kw.h"
+#include "mbedtls/oid.h"
+#include "mbedtls/padlock.h"
+#include "mbedtls/pem.h"
+#include "mbedtls/pk.h"
+#include "mbedtls/pk_internal.h"
+#include "mbedtls/pkcs12.h"
+#include "mbedtls/pkcs5.h"
+#include "mbedtls/platform_time.h"
+#include "mbedtls/platform_util.h"
+#include "mbedtls/poly1305.h"
+#include "mbedtls/psa_util.h"
+#include "mbedtls/ripemd160.h"
+#include "mbedtls/rsa.h"
+#include "mbedtls/rsa_internal.h"
+#include "mbedtls/sha1.h"
+#include "mbedtls/sha256.h"
+#include "mbedtls/sha512.h"
+#include "mbedtls/threading.h"
+#include "mbedtls/timing.h"
+#include "mbedtls/version.h"
+#include "mbedtls/xtea.h"
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#endif
+
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+#include "mbedtls/memory_buffer_alloc.h"
+#endif
+
+int main()
+{
+    mbedtls_platform_context *ctx = NULL;
+    mbedtls_platform_setup(ctx);
+    mbedtls_printf("CPP Build test\n");
+    mbedtls_platform_teardown(ctx);
+}
--- a/third_party/mbedtls/crypto/programs/test/query_compile_time_config.c
+++ b/third_party/mbedtls/crypto/programs/test/query_compile_time_config.c
@ -0,0 +1,56 @@
+/*
+ *  Query the Mbed TLS compile time configuration
+ *
+ *  Copyright (C) 2018, 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_printf       printf
+#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
+#endif
+
+#define USAGE                                                                \
+    "usage: %s <MBEDTLS_CONFIG>\n\n"                                         \
+    "This program takes one command line argument which corresponds to\n"    \
+    "the string representation of a Mbed TLS compile time configuration.\n"  \
+    "The value 0 will be returned if this configuration is defined in the\n" \
+    "Mbed TLS build and the macro expansion of that configuration will be\n" \
+    "printed (if any). Otherwise, 1 will be returned.\n"
+
+int query_config( const char *config );
+
+int main( int argc, char *argv[] )
+{
+    if ( argc != 2 )
+    {
+        mbedtls_printf( USAGE, argv[0] );
+        return( MBEDTLS_EXIT_FAILURE );
+    }
+
+    return( query_config( argv[1] ) );
+}
--- a/third_party/mbedtls/crypto/programs/test/query_config.c
+++ b/third_party/mbedtls/crypto/programs/test/query_config.c
--- a/third_party/mbedtls/crypto/programs/test/selftest.c
+++ b/third_party/mbedtls/crypto/programs/test/selftest.c
@ -0,0 +1,430 @@
+/*
+ *  Self-test demonstration program
+ *
+ *  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
+
+#include "mbedtls/entropy.h"
+#include "mbedtls/entropy_poll.h"
+#include "mbedtls/hmac_drbg.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/dhm.h"
+#include "mbedtls/gcm.h"
+#include "mbedtls/ccm.h"
+#include "mbedtls/cmac.h"
+#include "mbedtls/md2.h"
+#include "mbedtls/md4.h"
+#include "mbedtls/md5.h"
+#include "mbedtls/ripemd160.h"
+#include "mbedtls/sha1.h"
+#include "mbedtls/sha256.h"
+#include "mbedtls/sha512.h"
+#include "mbedtls/arc4.h"
+#include "mbedtls/des.h"
+#include "mbedtls/aes.h"
+#include "mbedtls/camellia.h"
+#include "mbedtls/aria.h"
+#include "mbedtls/chacha20.h"
+#include "mbedtls/poly1305.h"
+#include "mbedtls/chachapoly.h"
+#include "mbedtls/base64.h"
+#include "mbedtls/bignum.h"
+#include "mbedtls/rsa.h"
+#include "mbedtls/xtea.h"
+#include "mbedtls/pkcs5.h"
+#include "mbedtls/ecp.h"
+#include "mbedtls/ecjpake.h"
+#include "mbedtls/timing.h"
+#include "mbedtls/nist_kw.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#define mbedtls_printf     printf
+#define mbedtls_snprintf   snprintf
+#define mbedtls_exit       exit
+#define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
+#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
+#endif
+
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+#include "mbedtls/memory_buffer_alloc.h"
+#endif
+
+#if defined(MBEDTLS_CHECK_PARAMS)
+#include "mbedtls/platform_util.h"
+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
+
+static int test_snprintf( size_t n, const char ref_buf[10], int ref_ret )
+{
+    int ret;
+    char buf[10] = "xxxxxxxxx";
+    const char ref[10] = "xxxxxxxxx";
+
+    ret = mbedtls_snprintf( buf, n, "%s", "123" );
+    if( ret < 0 || (size_t) ret >= n )
+        ret = -1;
+
+    if( strncmp( ref_buf, buf, sizeof( buf ) ) != 0 ||
+        ref_ret != ret ||
+        memcmp( buf + n, ref + n, sizeof( buf ) - n ) != 0 )
+    {
+        return( 1 );
+    }
+
+    return( 0 );
+}
+
+static int run_test_snprintf( void )
+{
+    return( test_snprintf( 0, "xxxxxxxxx",  -1 ) != 0 ||
+            test_snprintf( 1, "",           -1 ) != 0 ||
+            test_snprintf( 2, "1",          -1 ) != 0 ||
+            test_snprintf( 3, "12",         -1 ) != 0 ||
+            test_snprintf( 4, "123",         3 ) != 0 ||
+            test_snprintf( 5, "123",         3 ) != 0 );
+}
+
+/*
+ * Check if a seed file is present, and if not create one for the entropy
+ * self-test. If this fails, we attempt the test anyway, so no error is passed
+ * back.
+ */
+#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_ENTROPY_C)
+#if defined(MBEDTLS_ENTROPY_NV_SEED) && !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
+static void create_entropy_seed_file( void )
+{
+    int result;
+    size_t output_len = 0;
+    unsigned char seed_value[MBEDTLS_ENTROPY_BLOCK_SIZE];
+
+    /* Attempt to read the entropy seed file. If this fails - attempt to write
+     * to the file to ensure one is present. */
+    result = mbedtls_platform_std_nv_seed_read( seed_value,
+                                                    MBEDTLS_ENTROPY_BLOCK_SIZE );
+    if( 0 == result )
+        return;
+
+    result = mbedtls_platform_entropy_poll( NULL,
+                                            seed_value,
+                                            MBEDTLS_ENTROPY_BLOCK_SIZE,
+                                            &output_len );
+    if( 0 != result )
+        return;
+
+    if( MBEDTLS_ENTROPY_BLOCK_SIZE != output_len )
+        return;
+
+    mbedtls_platform_std_nv_seed_write( seed_value, MBEDTLS_ENTROPY_BLOCK_SIZE );
+}
+#endif
+
+int mbedtls_entropy_self_test_wrapper( int verbose )
+{
+#if defined(MBEDTLS_ENTROPY_NV_SEED) && !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
+    create_entropy_seed_file( );
+#endif
+    return( mbedtls_entropy_self_test( verbose ) );
+}
+#endif
+
+#if defined(MBEDTLS_SELF_TEST)
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+int mbedtls_memory_buffer_alloc_free_and_self_test( int verbose )
+{
+    if( verbose != 0 )
+    {
+#if defined(MBEDTLS_MEMORY_DEBUG)
+        mbedtls_memory_buffer_alloc_status( );
+#endif
+    }
+    mbedtls_memory_buffer_alloc_free( );
+    return( mbedtls_memory_buffer_alloc_self_test( verbose ) );
+}
+#endif
+
+typedef struct
+{
+    const char *name;
+    int ( *function )( int );
+} selftest_t;
+
+const selftest_t selftests[] =
+{
+#if defined(MBEDTLS_MD2_C)
+    {"md2", mbedtls_md2_self_test},
+#endif
+#if defined(MBEDTLS_MD4_C)
+    {"md4", mbedtls_md4_self_test},
+#endif
+#if defined(MBEDTLS_MD5_C)
+    {"md5", mbedtls_md5_self_test},
+#endif
+#if defined(MBEDTLS_RIPEMD160_C)
+    {"ripemd160", mbedtls_ripemd160_self_test},
+#endif
+#if defined(MBEDTLS_SHA1_C)
+    {"sha1", mbedtls_sha1_self_test},
+#endif
+#if defined(MBEDTLS_SHA256_C)
+    {"sha256", mbedtls_sha256_self_test},
+#endif
+#if defined(MBEDTLS_SHA512_C)
+    {"sha512", mbedtls_sha512_self_test},
+#endif
+#if defined(MBEDTLS_ARC4_C)
+    {"arc4", mbedtls_arc4_self_test},
+#endif
+#if defined(MBEDTLS_DES_C)
+    {"des", mbedtls_des_self_test},
+#endif
+#if defined(MBEDTLS_AES_C)
+    {"aes", mbedtls_aes_self_test},
+#endif
+#if defined(MBEDTLS_GCM_C) && defined(MBEDTLS_AES_C)
+    {"gcm", mbedtls_gcm_self_test},
+#endif
+#if defined(MBEDTLS_CCM_C) && defined(MBEDTLS_AES_C)
+    {"ccm", mbedtls_ccm_self_test},
+#endif
+#if defined(MBEDTLS_NIST_KW_C) && defined(MBEDTLS_AES_C)
+    {"nist_kw", mbedtls_nist_kw_self_test},
+#endif
+#if defined(MBEDTLS_CMAC_C)
+    {"cmac", mbedtls_cmac_self_test},
+#endif
+#if defined(MBEDTLS_CHACHA20_C)
+    {"chacha20", mbedtls_chacha20_self_test},
+#endif
+#if defined(MBEDTLS_POLY1305_C)
+    {"poly1305", mbedtls_poly1305_self_test},
+#endif
+#if defined(MBEDTLS_CHACHAPOLY_C)
+    {"chacha20-poly1305", mbedtls_chachapoly_self_test},
+#endif
+#if defined(MBEDTLS_BASE64_C)
+    {"base64", mbedtls_base64_self_test},
+#endif
+#if defined(MBEDTLS_BIGNUM_C)
+    {"mpi", mbedtls_mpi_self_test},
+#endif
+#if defined(MBEDTLS_RSA_C)
+    {"rsa", mbedtls_rsa_self_test},
+#endif
+#if defined(MBEDTLS_XTEA_C)
+    {"xtea", mbedtls_xtea_self_test},
+#endif
+#if defined(MBEDTLS_CAMELLIA_C)
+    {"camellia", mbedtls_camellia_self_test},
+#endif
+#if defined(MBEDTLS_ARIA_C)
+    {"aria", mbedtls_aria_self_test},
+#endif
+#if defined(MBEDTLS_CTR_DRBG_C)
+    {"ctr_drbg", mbedtls_ctr_drbg_self_test},
+#endif
+#if defined(MBEDTLS_HMAC_DRBG_C)
+    {"hmac_drbg", mbedtls_hmac_drbg_self_test},
+#endif
+#if defined(MBEDTLS_ECP_C)
+    {"ecp", mbedtls_ecp_self_test},
+#endif
+#if defined(MBEDTLS_ECJPAKE_C)
+    {"ecjpake", mbedtls_ecjpake_self_test},
+#endif
+#if defined(MBEDTLS_DHM_C)
+    {"dhm", mbedtls_dhm_self_test},
+#endif
+#if defined(MBEDTLS_ENTROPY_C)
+    {"entropy", mbedtls_entropy_self_test_wrapper},
+#endif
+#if defined(MBEDTLS_PKCS5_C)
+    {"pkcs5", mbedtls_pkcs5_self_test},
+#endif
+/* Slower test after the faster ones */
+#if defined(MBEDTLS_TIMING_C)
+    {"timing", mbedtls_timing_self_test},
+#endif
+/* Heap test comes last */
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+    {"memory_buffer_alloc", mbedtls_memory_buffer_alloc_free_and_self_test},
+#endif
+    {NULL, NULL}
+};
+#endif /* MBEDTLS_SELF_TEST */
+
+int main( int argc, char *argv[] )
+{
+#if defined(MBEDTLS_SELF_TEST)
+    const selftest_t *test;
+#endif /* MBEDTLS_SELF_TEST */
+    char **argp;
+    int v = 1; /* v=1 for verbose mode */
+    int exclude_mode = 0;
+    int suites_tested = 0, suites_failed = 0;
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C) && defined(MBEDTLS_SELF_TEST)
+    unsigned char buf[1000000];
+#endif
+    void *pointer;
+
+    /*
+     * The C standard doesn't guarantee that all-bits-0 is the representation
+     * of a NULL pointer. We do however use that in our code for initializing
+     * structures, which should work on every modern platform. Let's be sure.
+     */
+    memset( &pointer, 0, sizeof( void * ) );
+    if( pointer != NULL )
+    {
+        mbedtls_printf( "all-bits-zero is not a NULL pointer\n" );
+        mbedtls_exit( MBEDTLS_EXIT_FAILURE );
+    }
+
+    /*
+     * Make sure we have a snprintf that correctly zero-terminates
+     */
+    if( run_test_snprintf() != 0 )
+    {
+        mbedtls_printf( "the snprintf implementation is broken\n" );
+        mbedtls_exit( MBEDTLS_EXIT_FAILURE );
+    }
+
+    for( argp = argv + ( argc >= 1 ? 1 : argc ); *argp != NULL; ++argp )
+    {
+        if( strcmp( *argp, "--quiet" ) == 0 ||
+            strcmp( *argp, "-q" ) == 0 )
+        {
+            v = 0;
+        }
+        else if( strcmp( *argp, "--exclude" ) == 0 ||
+                 strcmp( *argp, "-x" ) == 0 )
+        {
+            exclude_mode = 1;
+        }
+        else
+            break;
+    }
+
+    if( v != 0 )
+        mbedtls_printf( "\n" );
+
+#if defined(MBEDTLS_SELF_TEST)
+
+#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
+    mbedtls_memory_buffer_alloc_init( buf, sizeof(buf) );
+#endif
+
+    if( *argp != NULL && exclude_mode == 0 )
+    {
+        /* Run the specified tests */
+        for( ; *argp != NULL; argp++ )
+        {
+            for( test = selftests; test->name != NULL; test++ )
+            {
+                if( !strcmp( *argp, test->name ) )
+                {
+                    if( test->function( v )  != 0 )
+                    {
+                        suites_failed++;
+                    }
+                    suites_tested++;
+                    break;
+                }
+            }
+            if( test->name == NULL )
+            {
+                mbedtls_printf( "  Test suite %s not available -> failed\n\n", *argp );
+                suites_failed++;
+            }
+        }
+    }
+    else
+    {
+        /* Run all the tests except excluded ones */
+        for( test = selftests; test->name != NULL; test++ )
+        {
+            if( exclude_mode )
+            {
+                char **excluded;
+                for( excluded = argp; *excluded != NULL; ++excluded )
+                {
+                    if( !strcmp( *excluded, test->name ) )
+                        break;
+                }
+                if( *excluded )
+                {
+                    if( v )
+                        mbedtls_printf( "  Skip: %s\n", test->name );
+                    continue;
+                }
+            }
+            if( test->function( v )  != 0 )
+            {
+                suites_failed++;
+            }
+            suites_tested++;
+        }
+    }
+
+#else
+    (void) exclude_mode;
+    mbedtls_printf( " MBEDTLS_SELF_TEST not defined.\n" );
+#endif
+
+    if( v != 0 )
+    {
+        mbedtls_printf( "  Executed %d test suites\n\n", suites_tested );
+
+        if( suites_failed > 0)
+        {
+            mbedtls_printf( "  [ %d tests FAIL ]\n\n", suites_failed );
+        }
+        else
+        {
+            mbedtls_printf( "  [ All tests PASS ]\n\n" );
+        }
+#if defined(_WIN32)
+        mbedtls_printf( "  Press Enter to exit this program.\n" );
+        fflush( stdout ); getchar();
+#endif
+    }
+
+    if( suites_failed > 0)
+        mbedtls_exit( MBEDTLS_EXIT_FAILURE );
+
+    /* return() is here to prevent compiler warnings */
+    return( MBEDTLS_EXIT_SUCCESS );
+}
+
--- a/third_party/mbedtls/crypto/programs/test/zeroize.c
+++ b/third_party/mbedtls/crypto/programs/test/zeroize.c
@ -0,0 +1,101 @@
+/*
+ * Zeroize application for debugger-driven testing
+ *
+ * This is a simple test application used for debugger-driven testing to check
+ * whether calls to mbedtls_platform_zeroize() are being eliminated by compiler
+ * optimizations. This application is used by the GDB script at
+ * tests/scripts/test_zeroize.gdb under the assumption that the code does not
+ * change often (as opposed to the library code) because the script sets a
+ * breakpoint at the last return statement in the main() function of this
+ * program. The debugger facilities are then used to manually inspect the
+ * memory and verify that the call to mbedtls_platform_zeroize() was not
+ * eliminated.
+ *
+ *  Copyright (C) 2018, 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
+
+#include <stdio.h>
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#include <stdlib.h>
+#define mbedtls_printf     printf
+#define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
+#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
+#endif
+
+#include "mbedtls/platform_util.h"
+
+#define BUFFER_LEN 1024
+
+void usage( void )
+{
+    mbedtls_printf( "Zeroize is a simple program to assist with testing\n" );
+    mbedtls_printf( "the mbedtls_platform_zeroize() function by using the\n" );
+    mbedtls_printf( "debugger. This program takes a file as input and\n" );
+    mbedtls_printf( "prints the first %d characters. Usage:\n\n", BUFFER_LEN );
+    mbedtls_printf( "       zeroize <FILE>\n" );
+}
+
+int main( int argc, char** argv )
+{
+    int exit_code = MBEDTLS_EXIT_FAILURE;
+    FILE *fp;
+    char buf[BUFFER_LEN];
+    char *p = buf;
+    char *end = p + BUFFER_LEN;
+    int c;
+
+    if( argc != 2 )
+    {
+        mbedtls_printf( "This program takes exactly 1 agument\n" );
+        usage();
+        return( exit_code );
+    }
+
+    fp = fopen( argv[1], "r" );
+    if( fp == NULL )
+    {
+        mbedtls_printf( "Could not open file '%s'\n", argv[1] );
+        return( exit_code );
+    }
+
+    while( ( c = fgetc( fp ) ) != EOF && p < end - 1 )
+        *p++ = (char)c;
+    *p = '\0';
+
+    if( p - buf != 0 )
+    {
+        mbedtls_printf( "%s\n", buf );
+        exit_code = MBEDTLS_EXIT_SUCCESS;
+    }
+    else
+        mbedtls_printf( "The file is empty!\n" );
+
+    fclose( fp );
+    mbedtls_platform_zeroize( buf, sizeof( buf ) );
+
+    return( exit_code );
+}