openssl/crypto/rand/rand_win.c
Rich Salz 8389ec4b49 Add --with-rand-seed
Add a new config param to specify how the CSPRNG should be seeded.
Illegal values or nonsensical combinations (e.g., anything other
than "os" on VMS or HP VOS etc) result in build failures.
Add RDSEED support.
Add RDTSC but leave it disabled for now pending more investigation.

Refactor and reorganization all seeding files (rand_unix/win/vms) so
that they are simpler.

Only require 128 bits of seeding material.

Many document improvements, including why to not use RAND_add() and the
limitations around using load_file/write_file.
Document RAND_poll().

Cleanup Windows RAND_poll and return correct status

More completely initialize the default DRBG.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/3965)
2017-07-22 14:00:07 -04:00

103 lines
2.7 KiB
C

/*
* Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "internal/cryptlib.h"
#include <openssl/rand.h>
#include "rand_lcl.h"
#if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
# ifndef OPENSSL_RAND_SEED_OS
# error "Unsupported seeding method configured; must be os"
# endif
# include <windows.h>
/* On Windows 7 or higher use BCrypt instead of the legacy CryptoAPI */
# if defined(_MSC_VER) && defined(_WIN32_WINNT) && _WIN32_WINNT >= 0x0601
# define USE_BCRYPTGENRANDOM
# endif
# ifdef USE_BCRYPTGENRANDOM
# include <bcrypt.h>
# pragma comment(lib, "bcrypt.lib")
# ifndef STATUS_SUCCESS
# define STATUS_SUCCESS ((NTSTATUS)0x00000000L)
# endif
# else
# include <wincrypt.h>
/*
* Intel hardware RNG CSP -- available from
* http://developer.intel.com/design/security/rng/redist_license.htm
*/
# define PROV_INTEL_SEC 22
# define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"
# endif
int RAND_poll(void)
{
# ifndef USE_BCRYPTGENRANDOM
HCRYPTPROV hProvider;
# endif
DWORD w;
BYTE buf[RANDOMNESS_NEEDED];
int ok = 0;
# ifdef OPENSSL_RAND_SEED_RDTSC
rand_rdtsc();
# endif
# ifdef OPENSSL_RAND_SEED_RDCPU
if (rand_rdcpu())
ok++;
# endif
# ifdef USE_BCRYPTGENRANDOM
if (BCryptGenRandom(NULL, buf, (ULONG)sizeof(buf),
BCRYPT_USE_SYSTEM_PREFERRED_RNG) != STATUS_SUCCESS)
return 0;
RAND_add(buf, sizeof(buf), sizeof(buf));
return 1;
# else
/* poll the CryptoAPI PRNG */
if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
if (CryptGenRandom(hProvider, (DWORD)sizeof(buf), buf) != 0) {
RAND_add(buf, sizeof(buf), sizeof(buf));
ok++;
}
CryptReleaseContext(hProvider, 0);
}
/* poll the Pentium PRG with CryptoAPI */
if (CryptAcquireContextW(&hProvider, NULL, INTEL_DEF_PROV, PROV_INTEL_SEC,
CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
if (CryptGenRandom(hProvider, (DWORD)sizeof(buf), buf) != 0) {
RAND_add(buf, sizeof(buf), sizeof(buf));
ok++;
}
CryptReleaseContext(hProvider, 0);
}
# endif
return ok ? 1 : 0;
}
#if OPENSSL_API_COMPAT < 0x10100000L
int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam)
{
RAND_poll();
return RAND_status();
}
void RAND_screen(void)
{
RAND_poll();
}
#endif
#endif