1 /*
2 * Copyright 1995-2021 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 "internal/cryptlib.h"
11 #include <openssl/rand.h>
12 #include "crypto/rand_pool.h"
13 #include "crypto/rand.h"
14 #include "prov/seeding.h"
15
16 #if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
17
18 # ifndef OPENSSL_RAND_SEED_OS
19 # error "Unsupported seeding method configured; must be os"
20 # endif
21
22 # include <windows.h>
23 /* On Windows Vista or higher use BCrypt instead of the legacy CryptoAPI */
24 # if defined(_MSC_VER) && _MSC_VER > 1500 /* 1500 = Visual Studio 2008 */ \
25 && defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0600
26 # define USE_BCRYPTGENRANDOM
27 # endif
28
29 # ifdef USE_BCRYPTGENRANDOM
30 # include <bcrypt.h>
31 # ifdef _MSC_VER
32 # pragma comment(lib, "bcrypt.lib")
33 # endif
34 # ifndef STATUS_SUCCESS
35 # define STATUS_SUCCESS ((NTSTATUS)0x00000000L)
36 # endif
37 # else
38 # include <wincrypt.h>
39 /*
40 * Intel hardware RNG CSP -- available from
41 * http://developer.intel.com/design/security/rng/redist_license.htm
42 */
43 # define PROV_INTEL_SEC 22
44 # define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"
45 # endif
46
ossl_pool_acquire_entropy(RAND_POOL * pool)47 size_t ossl_pool_acquire_entropy(RAND_POOL *pool)
48 {
49 # ifndef USE_BCRYPTGENRANDOM
50 HCRYPTPROV hProvider;
51 # endif
52 unsigned char *buffer;
53 size_t bytes_needed;
54 size_t entropy_available = 0;
55
56
57 # ifdef OPENSSL_RAND_SEED_RDTSC
58 entropy_available = ossl_prov_acquire_entropy_from_tsc(pool);
59 if (entropy_available > 0)
60 return entropy_available;
61 # endif
62
63 # ifdef OPENSSL_RAND_SEED_RDCPU
64 entropy_available = ossl_prov_acquire_entropy_from_cpu(pool);
65 if (entropy_available > 0)
66 return entropy_available;
67 # endif
68
69 # ifdef USE_BCRYPTGENRANDOM
70 bytes_needed = ossl_rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
71 buffer = ossl_rand_pool_add_begin(pool, bytes_needed);
72 if (buffer != NULL) {
73 size_t bytes = 0;
74 if (BCryptGenRandom(NULL, buffer, bytes_needed,
75 BCRYPT_USE_SYSTEM_PREFERRED_RNG) == STATUS_SUCCESS)
76 bytes = bytes_needed;
77
78 ossl_rand_pool_add_end(pool, bytes, 8 * bytes);
79 entropy_available = ossl_rand_pool_entropy_available(pool);
80 }
81 if (entropy_available > 0)
82 return entropy_available;
83 # else
84 bytes_needed = ossl_rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
85 buffer = ossl_rand_pool_add_begin(pool, bytes_needed);
86 if (buffer != NULL) {
87 size_t bytes = 0;
88 /* poll the CryptoAPI PRNG */
89 if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
90 CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
91 if (CryptGenRandom(hProvider, bytes_needed, buffer) != 0)
92 bytes = bytes_needed;
93
94 CryptReleaseContext(hProvider, 0);
95 }
96
97 ossl_rand_pool_add_end(pool, bytes, 8 * bytes);
98 entropy_available = ossl_rand_pool_entropy_available(pool);
99 }
100 if (entropy_available > 0)
101 return entropy_available;
102
103 bytes_needed = ossl_rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
104 buffer = ossl_rand_pool_add_begin(pool, bytes_needed);
105 if (buffer != NULL) {
106 size_t bytes = 0;
107 /* poll the Pentium PRG with CryptoAPI */
108 if (CryptAcquireContextW(&hProvider, NULL,
109 INTEL_DEF_PROV, PROV_INTEL_SEC,
110 CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
111 if (CryptGenRandom(hProvider, bytes_needed, buffer) != 0)
112 bytes = bytes_needed;
113
114 CryptReleaseContext(hProvider, 0);
115 }
116 ossl_rand_pool_add_end(pool, bytes, 8 * bytes);
117 entropy_available = ossl_rand_pool_entropy_available(pool);
118 }
119 if (entropy_available > 0)
120 return entropy_available;
121 # endif
122
123 return ossl_rand_pool_entropy_available(pool);
124 }
125
126
ossl_pool_add_nonce_data(RAND_POOL * pool)127 int ossl_pool_add_nonce_data(RAND_POOL *pool)
128 {
129 struct {
130 DWORD pid;
131 DWORD tid;
132 FILETIME time;
133 } data;
134
135 /* Erase the entire structure including any padding */
136 memset(&data, 0, sizeof(data));
137
138 /*
139 * Add process id, thread id, and a high resolution timestamp to
140 * ensure that the nonce is unique with high probability for
141 * different process instances.
142 */
143 data.pid = GetCurrentProcessId();
144 data.tid = GetCurrentThreadId();
145 GetSystemTimeAsFileTime(&data.time);
146
147 return ossl_rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0);
148 }
149
ossl_rand_pool_init(void)150 int ossl_rand_pool_init(void)
151 {
152 return 1;
153 }
154
ossl_rand_pool_cleanup(void)155 void ossl_rand_pool_cleanup(void)
156 {
157 }
158
ossl_rand_pool_keep_random_devices_open(int keep)159 void ossl_rand_pool_keep_random_devices_open(int keep)
160 {
161 }
162
163 #endif
164
