1/*
2 * Copyright 2011-2018 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/opensslconf.h>
11
12#include <stdio.h>
13#include <string.h>
14#include "crypto/engine.h"
15#include "internal/cryptlib.h"
16#include <openssl/rand.h>
17#include <openssl/err.h>
18#include <openssl/crypto.h>
19
20#if (defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
21 defined(__x86_64) || defined(__x86_64__) || \
22 defined(_M_AMD64) || defined (_M_X64)) && defined(OPENSSL_CPUID_OBJ)
23
24size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len);
25
26static int get_random_bytes(unsigned char *buf, int num)
27{
28 if (num < 0) {
29 return 0;
30 }
31
32 return (size_t)num == OPENSSL_ia32_rdrand_bytes(buf, (size_t)num);
33}
34
35static int random_status(void)
36{
37 return 1;
38}
39
40static RAND_METHOD rdrand_meth = {
41 NULL, /* seed */
42 get_random_bytes,
43 NULL, /* cleanup */
44 NULL, /* add */
45 get_random_bytes,
46 random_status,
47};
48
49static int rdrand_init(ENGINE *e)
50{
51 return 1;
52}
53
54static const char *engine_e_rdrand_id = "rdrand";
55static const char *engine_e_rdrand_name = "Intel RDRAND engine";
56
57static int bind_helper(ENGINE *e)
58{
59 if (!ENGINE_set_id(e, engine_e_rdrand_id) ||
60 !ENGINE_set_name(e, engine_e_rdrand_name) ||
61 !ENGINE_set_flags(e, ENGINE_FLAGS_NO_REGISTER_ALL) ||
62 !ENGINE_set_init_function(e, rdrand_init) ||
63 !ENGINE_set_RAND(e, &rdrand_meth))
64 return 0;
65
66 return 1;
67}
68
69static ENGINE *ENGINE_rdrand(void)
70{
71 ENGINE *ret = ENGINE_new();
72 if (ret == NULL)
73 return NULL;
74 if (!bind_helper(ret)) {
75 ENGINE_free(ret);
76 return NULL;
77 }
78 return ret;
79}
80
81void engine_load_rdrand_int(void)
82{
83 if (OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) {
84 ENGINE *toadd = ENGINE_rdrand();
85 if (!toadd)
86 return;
87 ENGINE_add(toadd);
88 ENGINE_free(toadd);
89 ERR_clear_error();
90 }
91}
92#else
93void engine_load_rdrand_int(void)
94{
95}
96#endif
97