1 /* Copyright (c) 2014, Google Inc.
2  *
3  * Permission to use, copy, modify, and/or distribute this software for any
4  * purpose with or without fee is hereby granted, provided that the above
5  * copyright notice and this permission notice appear in all copies.
6  *
7  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14 
15 #include <openssl/rand.h>
16 
17 #if defined(OPENSSL_WINDOWS)
18 
19 #include <limits.h>
20 #include <stdlib.h>
21 
22 #pragma warning(push, 3)
23 
24 #include <windows.h>
25 
26 /* #define needed to link in RtlGenRandom(), a.k.a. SystemFunction036.  See the
27  * "Community Additions" comment on MSDN here:
28  * http://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx */
29 #define SystemFunction036 NTAPI SystemFunction036
30 #include <ntsecapi.h>
31 #undef SystemFunction036
32 
33 #pragma warning(pop)
34 
35 #include "internal.h"
36 
37 
RAND_cleanup(void)38 void RAND_cleanup(void) {
39 }
40 
CRYPTO_sysrand(uint8_t * out,size_t requested)41 void CRYPTO_sysrand(uint8_t *out, size_t requested) {
42   while (requested > 0) {
43     ULONG output_bytes_this_pass = ULONG_MAX;
44     if (requested < output_bytes_this_pass) {
45       output_bytes_this_pass = requested;
46     }
47     if (RtlGenRandom(out, output_bytes_this_pass) == FALSE) {
48       abort();
49     }
50     requested -= output_bytes_this_pass;
51     out += output_bytes_this_pass;
52   }
53   return;
54 }
55 
56 #endif  /* OPENSSL_WINDOWS */
57