1 /*
2 * Copyright 2011-2023 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 /* We need to use some engine deprecated APIs */
11 #define OPENSSL_SUPPRESS_DEPRECATED
12
13 #include <openssl/opensslconf.h>
14
15 #include <stdio.h>
16 #include <string.h>
17 #include "crypto/engine.h"
18 #include "internal/cryptlib.h"
19 #include <openssl/rand.h>
20 #include <openssl/err.h>
21 #include <openssl/crypto.h>
22
23 #if defined(__has_feature)
24 #if __has_feature(memory_sanitizer)
25 #include <sanitizer/msan_interface.h>
26 #endif
27 #endif
28
29 #if (defined(__i386) || defined(__i386__) || defined(_M_IX86) || defined(__x86_64) || defined(__x86_64__) || defined(_M_AMD64) || defined(_M_X64)) && defined(OPENSSL_CPUID_OBJ)
30
31 size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len);
32
get_random_bytes(unsigned char * buf,int num)33 static int get_random_bytes(unsigned char *buf, int num)
34 {
35 if (num < 0) {
36 return 0;
37 }
38
39 #if defined(__has_feature)
40 #if __has_feature(memory_sanitizer)
41 /*
42 * MemorySanitizer fails to understand asm and produces false positive
43 * use-of-uninitialized-value warnings.
44 */
45 __msan_unpoison(buf, num);
46 #endif
47 #endif
48
49 return (size_t)num == OPENSSL_ia32_rdrand_bytes(buf, (size_t)num);
50 }
51
random_status(void)52 static int random_status(void)
53 {
54 return 1;
55 }
56
57 static RAND_METHOD rdrand_meth = {
58 NULL, /* seed */
59 get_random_bytes,
60 NULL, /* cleanup */
61 NULL, /* add */
62 get_random_bytes,
63 random_status,
64 };
65
rdrand_init(ENGINE * e)66 static int rdrand_init(ENGINE *e)
67 {
68 return 1;
69 }
70
71 static const char *engine_e_rdrand_id = "rdrand";
72 static const char *engine_e_rdrand_name = "Intel RDRAND engine";
73
bind_helper(ENGINE * e)74 static int bind_helper(ENGINE *e)
75 {
76 if (!ENGINE_set_id(e, engine_e_rdrand_id) || !ENGINE_set_name(e, engine_e_rdrand_name) || !ENGINE_set_flags(e, ENGINE_FLAGS_NO_REGISTER_ALL) || !ENGINE_set_init_function(e, rdrand_init) || !ENGINE_set_RAND(e, &rdrand_meth))
77 return 0;
78
79 return 1;
80 }
81
ENGINE_rdrand(void)82 static ENGINE *ENGINE_rdrand(void)
83 {
84 ENGINE *ret = ENGINE_new();
85 if (ret == NULL)
86 return NULL;
87 if (!bind_helper(ret)) {
88 ENGINE_free(ret);
89 return NULL;
90 }
91 return ret;
92 }
93
engine_load_rdrand_int(void)94 void engine_load_rdrand_int(void)
95 {
96 if (OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) {
97 ENGINE *toadd = ENGINE_rdrand();
98 if (!toadd)
99 return;
100 ERR_set_mark();
101 ENGINE_add(toadd);
102 /*
103 * If the "add" worked, it gets a structural reference. So either way, we
104 * release our just-created reference.
105 */
106 ENGINE_free(toadd);
107 /*
108 * If the "add" didn't work, it was probably a conflict because it was
109 * already added (eg. someone calling ENGINE_load_blah then calling
110 * ENGINE_load_builtin_engines() perhaps).
111 */
112 ERR_pop_to_mark();
113 }
114 }
115 #else
engine_load_rdrand_int(void)116 void engine_load_rdrand_int(void)
117 {
118 }
119 #endif
120