test/secmemtest.c

   1 /*
   2  * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <openssl/crypto.h>
  11
  12 #include "testutil.h"
  13 #include "../e_os.h"
  14
  15 static int test_sec_mem(void)
  16 {
  17 #ifdef OPENSSL_SECURE_MEMORY
  18     int testresult = 0;
  19     char *p = NULL, *q = NULL, *r = NULL, *s = NULL;
  20
  21     TEST_info("Secure memory is implemented.");
  22
  23     s = OPENSSL_secure_malloc(20);
  24     /* s = non-secure 20 */
  25     if (!TEST_ptr(s)
  26         || !TEST_false(CRYPTO_secure_allocated(s)))
  27         goto end;
  28     r = OPENSSL_secure_malloc(20);
  29     /* r = non-secure 20, s = non-secure 20 */
  30     if (!TEST_ptr(r)
  31         || !TEST_true(CRYPTO_secure_malloc_init(4096, 32))
  32         || !TEST_false(CRYPTO_secure_allocated(r)))
  33         goto end;
  34     p = OPENSSL_secure_malloc(20);
  35     if (!TEST_ptr(p)
  36         /* r = non-secure 20, p = secure 20, s = non-secure 20 */
  37         || !TEST_true(CRYPTO_secure_allocated(p))
  38         /* 20 secure -> 32-byte minimum allocation unit */
  39         || !TEST_size_t_eq(CRYPTO_secure_used(), 32))
  40         goto end;
  41     q = OPENSSL_malloc(20);
  42     if (!TEST_ptr(q))
  43         goto end;
  44     /* r = non-secure 20, p = secure 20, q = non-secure 20, s = non-secure 20 */
  45     if (!TEST_false(CRYPTO_secure_allocated(q)))
  46         goto end;
  47     OPENSSL_secure_clear_free(s, 20);
  48     s = OPENSSL_secure_malloc(20);
  49     if (!TEST_ptr(s)
  50         /* r = non-secure 20, p = secure 20, q = non-secure 20, s = secure 20 */
  51         || !TEST_true(CRYPTO_secure_allocated(s))
  52         /* 2 * 20 secure -> 64 bytes allocated */
  53         || !TEST_size_t_eq(CRYPTO_secure_used(), 64))
  54         goto end;
  55     OPENSSL_secure_clear_free(p, 20);
  56     p = NULL;
  57     /* 20 secure -> 32 bytes allocated */
  58     if (!TEST_size_t_eq(CRYPTO_secure_used(), 32))
  59         goto end;
  60     OPENSSL_free(q);
  61     q = NULL;
  62     /* should not complete, as secure memory is still allocated */
  63     if (!TEST_false(CRYPTO_secure_malloc_done())
  64         || !TEST_true(CRYPTO_secure_malloc_initialized()))
  65         goto end;
  66     OPENSSL_secure_free(s);
  67     s = NULL;
  68     /* secure memory should now be 0, so done should complete */
  69     if (!TEST_size_t_eq(CRYPTO_secure_used(), 0)
  70         || !TEST_true(CRYPTO_secure_malloc_done())
  71         || !TEST_false(CRYPTO_secure_malloc_initialized()))
  72         goto end;
  73
  74     TEST_info("Possible infinite loop: allocate more than available");
  75     if (!TEST_true(CRYPTO_secure_malloc_init(32768, 16)))
  76         goto end;
  77     TEST_ptr_null(OPENSSL_secure_malloc((size_t)-1));
  78     TEST_true(CRYPTO_secure_malloc_done());
  79
  80     /*
  81      * If init fails, then initialized should be false, if not, this
  82      * could cause an infinite loop secure_malloc, but we don't test it
  83      */
  84     if (TEST_false(CRYPTO_secure_malloc_init(16, 16)) &&
  85         !TEST_false(CRYPTO_secure_malloc_initialized())) {
  86         TEST_true(CRYPTO_secure_malloc_done());
  87         goto end;
  88     }
  89
  90     /*-
  91      * There was also a possible infinite loop when the number of
  92      * elements was 1<<31, as |int i| was set to that, which is a
  93      * negative number. However, it requires minimum input values:
  94      *
  95      * CRYPTO_secure_malloc_init((size_t)1<<34, (size_t)1<<4);
  96      *
  97      * Which really only works on 64-bit systems, since it took 16 GB
  98      * secure memory arena to trigger the problem. It naturally takes
  99      * corresponding amount of available virtual and physical memory
 100      * for test to be feasible/representative. Since we can't assume
 101      * that every system is equipped with that much memory, the test
 102      * remains disabled. If the reader of this comment really wants
 103      * to make sure that infinite loop is fixed, they can enable the
 104      * code below.
 105      */
 106 # if 0
 107     /*-
 108      * On Linux and BSD this test has a chance to complete in minimal
 109      * time and with minimum side effects, because mlock is likely to
 110      * fail because of RLIMIT_MEMLOCK, which is customarily [much]
 111      * smaller than 16GB. In other words Linux and BSD users can be
 112      * limited by virtual space alone...
 113      */
 114     if (sizeof(size_t) > 4) {
 115         TEST_info("Possible infinite loop: 1<<31 limit");
 116         if (TEST_true(CRYPTO_secure_malloc_init((size_t)1<<34, (size_t)1<<4) != 0))
 117             TEST_true(CRYPTO_secure_malloc_done());
 118     }
 119 # endif
 120
 121     /* this can complete - it was not really secure */
 122     testresult = 1;
 123  end:
 124     OPENSSL_secure_free(p);
 125     OPENSSL_free(q);
 126     OPENSSL_secure_free(r);
 127     OPENSSL_secure_free(s);
 128     return testresult;
 129 #else
 130     TEST_info("Secure memory is *not* implemented.");
 131     /* Should fail. */
 132     return TEST_false(CRYPTO_secure_malloc_init(4096, 32));
 133 #endif
 134 }
 135
 136 static int test_sec_mem_clear(void)
 137 {
 138 #ifdef OPENSSL_SECURE_MEMORY
 139     const int size = 64;
 140     unsigned char *p = NULL;
 141     int i, res = 0;
 142
 143     if (!TEST_true(CRYPTO_secure_malloc_init(4096, 32))
 144             || !TEST_ptr(p = OPENSSL_secure_malloc(size)))
 145         goto err;
 146
 147     for (i = 0; i < size; i++)
 148         if (!TEST_uchar_eq(p[i], 0))
 149             goto err;
 150
 151     for (i = 0; i < size; i++)
 152         p[i] = (unsigned char)(i + ' ' + 1);
 153
 154     OPENSSL_secure_free(p);
 155
 156     /*
 157      * A deliberate use after free here to verify that the memory has been
 158      * cleared properly.  Since secure free doesn't return the memory to
 159      * libc's memory pool, it technically isn't freed.  However, the header
 160      * bytes have to be skipped and these consist of two pointers in the
 161      * current implementation.
 162      */
 163     for (i = sizeof(void *) * 2; i < size; i++)
 164         if (!TEST_uchar_eq(p[i], 0))
 165             return 0;
 166
 167     res = 1;
 168     p = NULL;
 169 err:
 170     OPENSSL_secure_free(p);
 171     CRYPTO_secure_malloc_done();
 172     return res;
 173 #else
 174     return 1;
 175 #endif
 176 }
 177
 178 int setup_tests(void)
 179 {
 180     ADD_TEST(test_sec_mem);
 181     ADD_TEST(test_sec_mem_clear);
 182     return 1;
 183 }