1*e0c4386eSCy Schubert /*
2*e0c4386eSCy Schubert * Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
3*e0c4386eSCy Schubert *
4*e0c4386eSCy Schubert * Licensed under the Apache License 2.0 (the "License"). You may not use
5*e0c4386eSCy Schubert * this file except in compliance with the License. You can obtain a copy
6*e0c4386eSCy Schubert * in the file LICENSE in the source distribution or at
7*e0c4386eSCy Schubert * https://www.openssl.org/source/license.html
8*e0c4386eSCy Schubert */
9*e0c4386eSCy Schubert
10*e0c4386eSCy Schubert #include <stdio.h>
11*e0c4386eSCy Schubert #include <stdlib.h>
12*e0c4386eSCy Schubert #include <string.h>
13*e0c4386eSCy Schubert #include "testutil.h"
14*e0c4386eSCy Schubert #include "internal/cryptlib.h"
15*e0c4386eSCy Schubert
16*e0c4386eSCy Schubert #if (defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
17*e0c4386eSCy Schubert defined(__x86_64) || defined(__x86_64__) || \
18*e0c4386eSCy Schubert defined(_M_AMD64) || defined (_M_X64)) && defined(OPENSSL_CPUID_OBJ)
19*e0c4386eSCy Schubert
20*e0c4386eSCy Schubert size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len);
21*e0c4386eSCy Schubert size_t OPENSSL_ia32_rdseed_bytes(unsigned char *buf, size_t len);
22*e0c4386eSCy Schubert
sanity_check_bytes(size_t (* rng)(unsigned char *,size_t),int rounds,int min_failures,int max_retries,int max_zero_words)23*e0c4386eSCy Schubert static int sanity_check_bytes(size_t (*rng)(unsigned char *, size_t),
24*e0c4386eSCy Schubert int rounds, int min_failures, int max_retries, int max_zero_words)
25*e0c4386eSCy Schubert {
26*e0c4386eSCy Schubert int testresult = 0;
27*e0c4386eSCy Schubert unsigned char prior[31] = {0}, buf[31] = {0}, check[7];
28*e0c4386eSCy Schubert int failures = 0, zero_words = 0;
29*e0c4386eSCy Schubert
30*e0c4386eSCy Schubert int i;
31*e0c4386eSCy Schubert for (i = 0; i < rounds; i++) {
32*e0c4386eSCy Schubert size_t generated = 0;
33*e0c4386eSCy Schubert
34*e0c4386eSCy Schubert int retry;
35*e0c4386eSCy Schubert for (retry = 0; retry < max_retries; retry++) {
36*e0c4386eSCy Schubert generated = rng(buf, sizeof(buf));
37*e0c4386eSCy Schubert if (generated == sizeof(buf))
38*e0c4386eSCy Schubert break;
39*e0c4386eSCy Schubert failures++;
40*e0c4386eSCy Schubert }
41*e0c4386eSCy Schubert
42*e0c4386eSCy Schubert /*-
43*e0c4386eSCy Schubert * Verify that we don't have too many unexpected runs of zeroes,
44*e0c4386eSCy Schubert * implying that we might be accidentally using the 32-bit RDRAND
45*e0c4386eSCy Schubert * instead of the 64-bit one on 64-bit systems.
46*e0c4386eSCy Schubert */
47*e0c4386eSCy Schubert size_t j;
48*e0c4386eSCy Schubert for (j = 0; j < sizeof(buf) - 1; j++) {
49*e0c4386eSCy Schubert if (buf[j] == 0 && buf[j+1] == 0) {
50*e0c4386eSCy Schubert zero_words++;
51*e0c4386eSCy Schubert }
52*e0c4386eSCy Schubert }
53*e0c4386eSCy Schubert
54*e0c4386eSCy Schubert if (!TEST_int_eq(generated, sizeof(buf)))
55*e0c4386eSCy Schubert goto end;
56*e0c4386eSCy Schubert if (!TEST_false(!memcmp(prior, buf, sizeof(buf))))
57*e0c4386eSCy Schubert goto end;
58*e0c4386eSCy Schubert
59*e0c4386eSCy Schubert /* Verify that the last 7 bytes of buf aren't all the same value */
60*e0c4386eSCy Schubert unsigned char *tail = &buf[sizeof(buf) - sizeof(check)];
61*e0c4386eSCy Schubert memset(check, tail[0], 7);
62*e0c4386eSCy Schubert if (!TEST_false(!memcmp(check, tail, sizeof(check))))
63*e0c4386eSCy Schubert goto end;
64*e0c4386eSCy Schubert
65*e0c4386eSCy Schubert /* Save the result and make sure it's different next time */
66*e0c4386eSCy Schubert memcpy(prior, buf, sizeof(buf));
67*e0c4386eSCy Schubert }
68*e0c4386eSCy Schubert
69*e0c4386eSCy Schubert if (!TEST_int_le(zero_words, max_zero_words))
70*e0c4386eSCy Schubert goto end;
71*e0c4386eSCy Schubert
72*e0c4386eSCy Schubert if (!TEST_int_ge(failures, min_failures))
73*e0c4386eSCy Schubert goto end;
74*e0c4386eSCy Schubert
75*e0c4386eSCy Schubert testresult = 1;
76*e0c4386eSCy Schubert end:
77*e0c4386eSCy Schubert return testresult;
78*e0c4386eSCy Schubert }
79*e0c4386eSCy Schubert
sanity_check_rdrand_bytes(void)80*e0c4386eSCy Schubert static int sanity_check_rdrand_bytes(void)
81*e0c4386eSCy Schubert {
82*e0c4386eSCy Schubert return sanity_check_bytes(OPENSSL_ia32_rdrand_bytes, 1000, 0, 10, 10);
83*e0c4386eSCy Schubert }
84*e0c4386eSCy Schubert
sanity_check_rdseed_bytes(void)85*e0c4386eSCy Schubert static int sanity_check_rdseed_bytes(void)
86*e0c4386eSCy Schubert {
87*e0c4386eSCy Schubert /*-
88*e0c4386eSCy Schubert * RDSEED may take many retries to succeed; note that this is effectively
89*e0c4386eSCy Schubert * multiplied by the 8x retry loop in asm, and failure probabilities are
90*e0c4386eSCy Schubert * increased by the fact that we need either 4 or 8 samples depending on
91*e0c4386eSCy Schubert * the platform.
92*e0c4386eSCy Schubert */
93*e0c4386eSCy Schubert return sanity_check_bytes(OPENSSL_ia32_rdseed_bytes, 1000, 1, 10000, 10);
94*e0c4386eSCy Schubert }
95*e0c4386eSCy Schubert
setup_tests(void)96*e0c4386eSCy Schubert int setup_tests(void)
97*e0c4386eSCy Schubert {
98*e0c4386eSCy Schubert OPENSSL_cpuid_setup();
99*e0c4386eSCy Schubert
100*e0c4386eSCy Schubert int have_rdseed = (OPENSSL_ia32cap_P[2] & (1 << 18)) != 0;
101*e0c4386eSCy Schubert int have_rdrand = (OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) != 0;
102*e0c4386eSCy Schubert
103*e0c4386eSCy Schubert if (have_rdrand) {
104*e0c4386eSCy Schubert ADD_TEST(sanity_check_rdrand_bytes);
105*e0c4386eSCy Schubert }
106*e0c4386eSCy Schubert
107*e0c4386eSCy Schubert if (have_rdseed) {
108*e0c4386eSCy Schubert ADD_TEST(sanity_check_rdseed_bytes);
109*e0c4386eSCy Schubert }
110*e0c4386eSCy Schubert
111*e0c4386eSCy Schubert return 1;
112*e0c4386eSCy Schubert }
113*e0c4386eSCy Schubert
114*e0c4386eSCy Schubert
115*e0c4386eSCy Schubert #else
116*e0c4386eSCy Schubert
setup_tests(void)117*e0c4386eSCy Schubert int setup_tests(void)
118*e0c4386eSCy Schubert {
119*e0c4386eSCy Schubert return 1;
120*e0c4386eSCy Schubert }
121*e0c4386eSCy Schubert
122*e0c4386eSCy Schubert #endif
123