/* crypto/rand/rand_lib.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include <time.h>
#include "cryptlib.h"
#include <openssl/rand.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif
#ifdef OPENSSL_FIPS
#include <openssl/fips.h>
#include <openssl/fips_rand.h>
#endif
#ifndef OPENSSL_NO_ENGINE
/* non-NULL if default_RAND_meth is ENGINE-provided */
static ENGINE *funct_ref =NULL;
#endif
static const RAND_METHOD *default_RAND_meth = NULL;
int RAND_set_rand_method(const RAND_METHOD *meth)
{
#ifndef OPENSSL_NO_ENGINE
if(funct_ref)
{
ENGINE_finish(funct_ref);
funct_ref = NULL;
}
#endif
default_RAND_meth = meth;
return 1;
}
const RAND_METHOD *RAND_get_rand_method(void)
{
if (!default_RAND_meth)
{
#ifndef OPENSSL_NO_ENGINE
ENGINE *e = ENGINE_get_default_RAND();
if(e)
{
default_RAND_meth = ENGINE_get_RAND(e);
if(!default_RAND_meth)
{
ENGINE_finish(e);
e = NULL;
}
}
if(e)
funct_ref = e;
else
#endif
default_RAND_meth = RAND_SSLeay();
}
return default_RAND_meth;
}
#ifndef OPENSSL_NO_ENGINE
int RAND_set_rand_engine(ENGINE *engine)
{
const RAND_METHOD *tmp_meth = NULL;
if(engine)
{
if(!ENGINE_init(engine))
return 0;
tmp_meth = ENGINE_get_RAND(engine);
if(!tmp_meth)
{
ENGINE_finish(engine);
return 0;
}
}
/* This function releases any prior ENGINE so call it first */
RAND_set_rand_method(tmp_meth);
funct_ref = engine;
return 1;
}
#endif
void RAND_cleanup(void)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->cleanup)
meth->cleanup();
RAND_set_rand_method(NULL);
}
void RAND_seed(const void *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->seed)
meth->seed(buf,num);
}
void RAND_add(const void *buf, int num, double entropy)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->add)
meth->add(buf,num,entropy);
}
int RAND_bytes(unsigned char *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->bytes)
return meth->bytes(buf,num);
return(-1);
}
int RAND_pseudo_bytes(unsigned char *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->pseudorand)
return meth->pseudorand(buf,num);
return(-1);
}
int RAND_status(void)
{
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth && meth->status)
return meth->status();
return 0;
}
#ifdef OPENSSL_FIPS
/* FIPS DRBG initialisation code. This sets up the DRBG for use by the
* rest of OpenSSL.
*/
/* Entropy gatherer: use standard OpenSSL PRNG to seed (this will gather
* entropy internally through RAND_poll().
*/
static size_t drbg_get_entropy(DRBG_CTX *ctx, unsigned char **pout,
int entropy, size_t min_len, size_t max_len)
{
/* Round up request to multiple of block size */
min_len = ((min_len + 19) / 20) * 20;
*pout = OPENSSL_malloc(min_len);
if (!*pout)
return 0;
if (RAND_SSLeay()->bytes(*pout, min_len) <= 0)
{
OPENSSL_free(*pout);
*pout = NULL;
return 0;
}
return min_len;
}
static void drbg_free_entropy(DRBG_CTX *ctx, unsigned char *out, size_t olen)
{
if (out)
{
OPENSSL_cleanse(out, olen);
OPENSSL_free(out);
}
}
/* Set "additional input" when generating random data. This uses the
* current PID, a time value and a counter.
*/
static size_t drbg_get_adin(DRBG_CTX *ctx, unsigned char **pout)
{
/* Use of static variables is OK as this happens under a lock */
static unsigned char buf[16];
static unsigned long counter;
FIPS_get_timevec(buf, &counter);
*pout = buf;
return sizeof(buf);
}
/* RAND_add() and RAND_seed() pass through to OpenSSL PRNG so it is
* correctly seeded by RAND_poll().
*/
static int drbg_rand_add(DRBG_CTX *ctx, const void *in, int inlen,
double entropy)
{
RAND_SSLeay()->add(in, inlen, entropy);
return 1;
}
static int drbg_rand_seed(DRBG_CTX *ctx, const void *in, int inlen)
{
RAND_SSLeay()->seed(in, inlen);
return 1;
}
#ifndef OPENSSL_DRBG_DEFAULT_TYPE
#define OPENSSL_DRBG_DEFAULT_TYPE NID_aes_256_ctr
#endif
#ifndef OPENSSL_DRBG_DEFAULT_FLAGS
#define OPENSSL_DRBG_DEFAULT_FLAGS DRBG_FLAG_CTR_USE_DF
#endif
static int fips_drbg_type = OPENSSL_DRBG_DEFAULT_TYPE;
static int fips_drbg_flags = OPENSSL_DRBG_DEFAULT_FLAGS;
void RAND_set_fips_drbg_type(int type, int flags)
{
fips_drbg_type = type;
fips_drbg_flags = flags;
}
int RAND_init_fips(void)
{
DRBG_CTX *dctx;
size_t plen;
unsigned char pers[32], *p;
dctx = FIPS_get_default_drbg();
if (FIPS_drbg_init(dctx, fips_drbg_type, fips_drbg_flags) <= 0)
{
RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INITIALISING_DRBG);
return 0;
}
FIPS_drbg_set_callbacks(dctx,
drbg_get_entropy, drbg_free_entropy, 20,
drbg_get_entropy, drbg_free_entropy);
FIPS_drbg_set_rand_callbacks(dctx, drbg_get_adin, 0,
drbg_rand_seed, drbg_rand_add);
/* Personalisation string: a string followed by date time vector */
strcpy((char *)pers, "OpenSSL DRBG2.0");
plen = drbg_get_adin(dctx, &p);
memcpy(pers + 16, p, plen);
if (FIPS_drbg_instantiate(dctx, pers, sizeof(pers)) <= 0)
{
RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INSTANTIATING_DRBG);
return 0;
}
FIPS_rand_set_method(FIPS_drbg_method());
return 1;
}
#endif