boringssl/crypto/fipsmodule/rand/internal.h
David Benjamin 2e819d8be4 Unwind RDRAND functions correctly on Windows.
But for the ABI conversion bits, these are just leaf functions and don't
even need unwind tables. Just renumber the registers on Windows to only
used volatile ones.

In doing so, this switches to writing rdrand explicitly. perlasm already
knows how to manually encode it and our minimum assembler versions
surely cover rdrand by now anyway. Also add the .size directive. I'm not
sure what it's used for, but the other files have it.

(This isn't a generally reusable technique. The more complex functions
will need actual unwind codes.)

Bug: 259
Change-Id: I1d5669bcf8b6e34939885d78aea6f60597be1528
Reviewed-on: https://boringssl-review.googlesource.com/c/34867
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2019-02-12 20:24:27 +00:00

110 lines
4.2 KiB
C

/* Copyright (c) 2015, 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. */
#ifndef OPENSSL_HEADER_CRYPTO_RAND_INTERNAL_H
#define OPENSSL_HEADER_CRYPTO_RAND_INTERNAL_H
#include <openssl/aes.h>
#include <openssl/cpu.h>
#include "../../internal.h"
#include "../modes/internal.h"
#if defined(__cplusplus)
extern "C" {
#endif
// RAND_bytes_with_additional_data samples from the RNG after mixing 32 bytes
// from |user_additional_data| in.
void RAND_bytes_with_additional_data(uint8_t *out, size_t out_len,
const uint8_t user_additional_data[32]);
// CRYPTO_sysrand fills |len| bytes at |buf| with entropy from the operating
// system.
void CRYPTO_sysrand(uint8_t *buf, size_t len);
// rand_fork_unsafe_buffering_enabled returns whether fork-unsafe buffering has
// been enabled via |RAND_enable_fork_unsafe_buffering|.
int rand_fork_unsafe_buffering_enabled(void);
// CTR_DRBG_STATE contains the state of a CTR_DRBG based on AES-256. See SP
// 800-90Ar1.
typedef struct {
AES_KEY ks;
block128_f block;
ctr128_f ctr;
union {
uint8_t bytes[16];
uint32_t words[4];
} counter;
uint64_t reseed_counter;
} CTR_DRBG_STATE;
// See SP 800-90Ar1, table 3.
#define CTR_DRBG_ENTROPY_LEN 48
#define CTR_DRBG_MAX_GENERATE_LENGTH 65536
// CTR_DRBG_init initialises |*drbg| given |CTR_DRBG_ENTROPY_LEN| bytes of
// entropy in |entropy| and, optionally, a personalization string up to
// |CTR_DRBG_ENTROPY_LEN| bytes in length. It returns one on success and zero
// on error.
OPENSSL_EXPORT int CTR_DRBG_init(CTR_DRBG_STATE *drbg,
const uint8_t entropy[CTR_DRBG_ENTROPY_LEN],
const uint8_t *personalization,
size_t personalization_len);
// CTR_DRBG_reseed reseeds |drbg| given |CTR_DRBG_ENTROPY_LEN| bytes of entropy
// in |entropy| and, optionally, up to |CTR_DRBG_ENTROPY_LEN| bytes of
// additional data. It returns one on success or zero on error.
OPENSSL_EXPORT int CTR_DRBG_reseed(CTR_DRBG_STATE *drbg,
const uint8_t entropy[CTR_DRBG_ENTROPY_LEN],
const uint8_t *additional_data,
size_t additional_data_len);
// CTR_DRBG_generate processes to up |CTR_DRBG_ENTROPY_LEN| bytes of additional
// data (if any) and then writes |out_len| random bytes to |out|, where
// |out_len| <= |CTR_DRBG_MAX_GENERATE_LENGTH|. It returns one on success or
// zero on error.
OPENSSL_EXPORT int CTR_DRBG_generate(CTR_DRBG_STATE *drbg, uint8_t *out,
size_t out_len,
const uint8_t *additional_data,
size_t additional_data_len);
// CTR_DRBG_clear zeroises the state of |drbg|.
OPENSSL_EXPORT void CTR_DRBG_clear(CTR_DRBG_STATE *drbg);
#if defined(OPENSSL_X86_64) && !defined(OPENSSL_NO_ASM)
OPENSSL_INLINE int have_rdrand(void) {
return (OPENSSL_ia32cap_get()[1] & (1u << 30)) != 0;
}
// CRYPTO_rdrand writes eight bytes of random data from the hardware RNG to
// |out|. It returns one on success or zero on hardware failure.
int CRYPTO_rdrand(uint8_t out[8]);
// CRYPTO_rdrand_multiple8_buf fills |len| bytes at |buf| with random data from
// the hardware RNG. The |len| argument must be a multiple of eight. It returns
// one on success and zero on hardware failure.
int CRYPTO_rdrand_multiple8_buf(uint8_t *buf, size_t len);
#endif // OPENSSL_X86_64 && !OPENSSL_NO_ASM
#if defined(__cplusplus)
} // extern C
#endif
#endif // OPENSSL_HEADER_CRYPTO_RAND_INTERNAL_H