xref: /freebsd/crypto/openssl/test/secmemtest.c (revision 397e83df75e0fcd0d3fcb95ae4d794cb7600fc89)
1 /*
2  * Copyright 2015-2020 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 #ifndef OPENSSL_NO_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, 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, 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 #ifndef OPENSSL_NO_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 }
184