openssl/crypto/rand/rand_win.c
Dr. Matthias St. Pierre 6decf9436f Publish the RAND_DRBG API
Fixes #4403

This commit moves the internal header file "internal/rand.h" to
<openssl/rand_drbg.h>, making the RAND_DRBG API public.
The RAND_POOL API remains private, its function prototypes were
moved to "internal/rand_int.h" and converted to lowercase.

Documentation for the new API is work in progress on GitHub #5461.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5462)
2018-03-15 18:58:38 +01:00

131 lines
3.8 KiB
C

/*
* Copyright 1995-2018 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"
#include "internal/rand_int.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
size_t rand_pool_acquire_entropy(RAND_POOL *pool)
{
# ifndef USE_BCRYPTGENRANDOM
HCRYPTPROV hProvider;
# endif
unsigned char *buffer;
size_t bytes_needed;
size_t entropy_available = 0;
# ifdef OPENSSL_RAND_SEED_RDTSC
entropy_available = rand_acquire_entropy_from_tsc(pool);
if (entropy_available > 0)
return entropy_available;
# endif
# ifdef OPENSSL_RAND_SEED_RDCPU
entropy_available = rand_acquire_entropy_from_cpu(pool);
if (entropy_available > 0)
return entropy_available;
# endif
# ifdef USE_BCRYPTGENRANDOM
bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
buffer = rand_pool_add_begin(pool, bytes_needed);
if (buffer != NULL) {
size_t bytes = 0;
if (BCryptGenRandom(NULL, buffer, bytes_needed,
BCRYPT_USE_SYSTEM_PREFERRED_RNG) == STATUS_SUCCESS)
bytes = bytes_needed;
entropy_available = rand_pool_add_end(pool, bytes, 8 * bytes);
}
if (entropy_available > 0)
return entropy_available;
# else
bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
buffer = rand_pool_add_begin(pool, bytes_needed);
if (buffer != NULL) {
size_t bytes = 0;
/* poll the CryptoAPI PRNG */
if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT | CRYPT_SILENT) != 0) {
if (CryptGenRandom(hProvider, bytes_needed, buffer) != 0)
bytes = bytes_needed;
CryptReleaseContext(hProvider, 0);
}
entropy_available = rand_pool_add_end(pool, bytes, 8 * bytes);
}
if (entropy_available > 0)
return entropy_available;
bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
buffer = rand_pool_add_begin(pool, bytes_needed);
if (buffer != NULL) {
size_t bytes = 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, bytes_needed, buffer) != 0)
bytes = bytes_needed;
CryptReleaseContext(hProvider, 0);
}
entropy_available = rand_pool_add_end(pool, bytes, 8 * bytes);
}
if (entropy_available > 0)
return entropy_available;
# endif
return rand_pool_entropy_available(pool);
}
# 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