boringssl/crypto/rand/windows.c
David Benjamin dfc2948c73 Call RtlGenRandom directly in RAND_bytes.
It works within the Chromium sandbox, unlike CryptAcquireContext
and CryptGenRandom which requires the HCRYPTPROV be pre-warmed and held within
the sandbox. Also account for the mismatch between size_t and ULONG/DWORD.

See https://chromium.googlesource.com/chromium/src/+/master/base/rand_util_win.cc

BUG=crbug.com/429919

Change-Id: Ia684124736c0c039ca9410509973192a597856ab
Reviewed-on: https://boringssl-review.googlesource.com/2190
Reviewed-by: Adam Langley <agl@google.com>
2014-11-05 00:42:07 +00:00

51 lines
1.6 KiB
C

/* Copyright (c) 2014, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <openssl/rand.h>
#if defined(OPENSSL_WINDOWS)
#include <limits.h>
#include <stdlib.h>
#include <Windows.h>
/* #define needed to link in RtlGenRandom(), a.k.a. SystemFunction036. See the
* "Community Additions" comment on MSDN here:
* http://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx */
#define SystemFunction036 NTAPI SystemFunction036
#include <NTSecAPI.h>
#undef SystemFunction036
void RAND_cleanup(void) {
}
int RAND_bytes(uint8_t *out, size_t requested) {
while (requested > 0) {
ULONG output_bytes_this_pass = ULONG_MAX;
if (requested < output_bytes_this_pass) {
output_bytes_this_pass = requested;
}
if (RtlGenRandom(out, output_bytes_this_pass) == FALSE) {
abort();
return 0;
}
requested -= output_bytes_this_pass;
out += output_bytes_this_pass;
}
return 1;
}
#endif /* OPENSSL_WINDOWS */