office-gobmx/sal/rtl/source/random.c

338 lines
9.6 KiB
C

/*************************************************************************
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* Copyright 2000, 2010 Oracle and/or its affiliates.
*
* OpenOffice.org - a multi-platform office productivity suite
*
* This file is part of OpenOffice.org.
*
* OpenOffice.org is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3
* only, as published by the Free Software Foundation.
*
* OpenOffice.org is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License version 3 for more details
* (a copy is included in the LICENSE file that accompanied this code).
*
* You should have received a copy of the GNU Lesser General Public License
* version 3 along with OpenOffice.org. If not, see
* <http://www.openoffice.org/license.html>
* for a copy of the LGPLv3 License.
*
************************************************************************/
#define _RTL_RANDOM_C_ "$Revision: 1.6 $"
#include <sal/types.h>
#include <osl/thread.h>
#include <osl/time.h>
#include <rtl/alloc.h>
#include <rtl/digest.h>
#include <rtl/random.h>
#include <osl/time.h>
/*========================================================================
*
* rtlRandom internals.
*
*======================================================================*/
#define RTL_RANDOM_RNG_1(a) ((a) * 16807L)
#define RTL_RANDOM_RNG_2(a) ((a) * 65539L)
#define RTL_RANDOM_RNG(x, y, z) \
{ \
(x) = 170 * ((x) % 178) - 63 * ((x) / 178); \
if ((x) < 0) (x) += 30328L; \
\
(y) = 171 * ((y) % 177) - 2 * ((y) / 177); \
if ((y) < 0) (y) += 30269L; \
\
(z) = 172 * ((z) % 176) - 35 * ((z) / 176); \
if ((z) < 0) (z) += 30307L; \
}
/** RandomData_Impl.
*/
typedef struct random_data_impl_st
{
sal_Int16 m_nX;
sal_Int16 m_nY;
sal_Int16 m_nZ;
} RandomData_Impl;
/** __rtl_random_data.
*/
static double __rtl_random_data (RandomData_Impl *pImpl);
/** RandomPool_Impl.
*/
#define RTL_RANDOM_DIGEST rtl_Digest_AlgorithmMD5
#define RTL_RANDOM_SIZE_DIGEST RTL_DIGEST_LENGTH_MD5
#define RTL_RANDOM_SIZE_POOL 1023
typedef struct random_pool_impl_st
{
rtlDigest m_hDigest;
sal_uInt8 m_pDigest[RTL_RANDOM_SIZE_DIGEST];
sal_uInt8 m_pData[RTL_RANDOM_SIZE_POOL + 1];
sal_uInt32 m_nData;
sal_uInt32 m_nIndex;
sal_uInt32 m_nCount;
} RandomPool_Impl;
/** __rtl_random_initPool.
*/
static sal_Bool __rtl_random_initPool (
RandomPool_Impl *pImpl);
/** __rtl_random_seedPool.
*/
static void __rtl_random_seedPool (
RandomPool_Impl *pImpl, const sal_uInt8 *pBuffer, sal_Size nBufLen);
/** __rtl_random_readPool.
*/
static void __rtl_random_readPool (
RandomPool_Impl *pImpl, sal_uInt8 *pBuffer, sal_Size nBufLen);
/*
* __rtl_random_data.
*/
static double __rtl_random_data (RandomData_Impl *pImpl)
{
register double random;
RTL_RANDOM_RNG (pImpl->m_nX, pImpl->m_nY, pImpl->m_nZ);
random = (((double)(pImpl->m_nX) / 30328.0) +
((double)(pImpl->m_nY) / 30269.0) +
((double)(pImpl->m_nZ) / 30307.0) );
random -= ((double)((sal_uInt32)(random)));
return (random);
}
/*
* __rtl_random_initPool.
*/
static sal_Bool __rtl_random_initPool (RandomPool_Impl *pImpl)
{
pImpl->m_hDigest = rtl_digest_create (RTL_RANDOM_DIGEST);
if (pImpl->m_hDigest)
{
oslThreadIdentifier id;
TimeValue tv;
RandomData_Impl rd;
double seed;
/* The use of uninitialized stack variables as a way to
* enhance the entropy of the random pool triggers
* memory checkers like purify and valgrind.
*/
/*
__rtl_random_seedPool (pImpl, (sal_uInt8*)&id, sizeof(id));
__rtl_random_seedPool (pImpl, (sal_uInt8*)&tv, sizeof(tv));
__rtl_random_seedPool (pImpl, (sal_uInt8*)&rd, sizeof(rd));
*/
id = osl_getThreadIdentifier (NULL);
id = RTL_RANDOM_RNG_2(RTL_RANDOM_RNG_1(id));
__rtl_random_seedPool (pImpl, (sal_uInt8*)&id, sizeof(id));
osl_getSystemTime (&tv);
tv.Seconds = RTL_RANDOM_RNG_2(tv.Seconds);
tv.Nanosec = RTL_RANDOM_RNG_2(tv.Nanosec);
__rtl_random_seedPool (pImpl, (sal_uInt8*)&tv, sizeof(tv));
rd.m_nX = (sal_Int16)(((id >> 1) << 1) + 1);
rd.m_nY = (sal_Int16)(((tv.Seconds >> 1) << 1) + 1);
rd.m_nZ = (sal_Int16)(((tv.Nanosec >> 1) << 1) + 1);
__rtl_random_seedPool (pImpl, (sal_uInt8*)&rd, sizeof(rd));
while (pImpl->m_nData < RTL_RANDOM_SIZE_POOL)
{
seed = __rtl_random_data (&rd);
__rtl_random_seedPool (pImpl, (sal_uInt8*)&seed, sizeof(seed));
}
return sal_True;
}
return sal_False;
}
/*
* __rtl_random_seedPool.
*/
static void __rtl_random_seedPool (
RandomPool_Impl *pImpl, const sal_uInt8 *pBuffer, sal_Size nBufLen)
{
sal_Size i;
sal_sSize j, k;
for (i = 0; i < nBufLen; i += RTL_RANDOM_SIZE_DIGEST)
{
j = nBufLen - i;
if (j > RTL_RANDOM_SIZE_DIGEST)
j = RTL_RANDOM_SIZE_DIGEST;
rtl_digest_update (
pImpl->m_hDigest, pImpl->m_pDigest, RTL_RANDOM_SIZE_DIGEST);
k = (pImpl->m_nIndex + j) - RTL_RANDOM_SIZE_POOL;
if (k > 0)
{
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[pImpl->m_nIndex]), j - k);
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[0]), k);
}
else
{
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[pImpl->m_nIndex]), j);
}
rtl_digest_update (pImpl->m_hDigest, pBuffer, j);
pBuffer += j;
rtl_digest_get (
pImpl->m_hDigest, pImpl->m_pDigest, RTL_RANDOM_SIZE_DIGEST);
for (k = 0; k < j; k++)
{
pImpl->m_pData[pImpl->m_nIndex++] ^= pImpl->m_pDigest[k];
if (pImpl->m_nIndex >= RTL_RANDOM_SIZE_POOL)
{
pImpl->m_nData = RTL_RANDOM_SIZE_POOL;
pImpl->m_nIndex = 0;
}
}
}
if (pImpl->m_nIndex > pImpl->m_nData)
pImpl->m_nData = pImpl->m_nIndex;
}
/*
* __rtl_random_readPool.
*/
static void __rtl_random_readPool (
RandomPool_Impl *pImpl, sal_uInt8 *pBuffer, sal_Size nBufLen)
{
sal_Int32 j, k;
while (nBufLen > 0)
{
j = nBufLen;
if (j > RTL_RANDOM_SIZE_DIGEST/2)
j = RTL_RANDOM_SIZE_DIGEST/2;
nBufLen -= j;
rtl_digest_update (
pImpl->m_hDigest,
&(pImpl->m_pDigest[RTL_RANDOM_SIZE_DIGEST/2]),
RTL_RANDOM_SIZE_DIGEST/2);
k = (pImpl->m_nIndex + j) - pImpl->m_nData;
if (k > 0)
{
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[pImpl->m_nIndex]), j - k);
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[0]), k);
}
else
{
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_pData[pImpl->m_nIndex]), j);
}
rtl_digest_get (
pImpl->m_hDigest, pImpl->m_pDigest, RTL_RANDOM_SIZE_DIGEST);
for (k = 0; k < j; k++)
{
if (pImpl->m_nIndex >= pImpl->m_nData) pImpl->m_nIndex = 0;
pImpl->m_pData[pImpl->m_nIndex++] ^= pImpl->m_pDigest[k];
*pBuffer++ = pImpl->m_pDigest[k + RTL_RANDOM_SIZE_DIGEST/2];
}
}
pImpl->m_nCount++;
rtl_digest_update (
pImpl->m_hDigest, &(pImpl->m_nCount), sizeof(pImpl->m_nCount));
rtl_digest_update (
pImpl->m_hDigest, pImpl->m_pDigest, RTL_RANDOM_SIZE_DIGEST);
rtl_digest_get (
pImpl->m_hDigest, pImpl->m_pDigest, RTL_RANDOM_SIZE_DIGEST);
}
/*========================================================================
*
* rtlRandom implementation.
*
*======================================================================*/
/*
* rtl_random_createPool.
*/
rtlRandomPool SAL_CALL rtl_random_createPool (void)
{
RandomPool_Impl *pImpl = (RandomPool_Impl*)NULL;
pImpl = (RandomPool_Impl*)rtl_allocateZeroMemory (sizeof(RandomPool_Impl));
if (pImpl)
{
if (!__rtl_random_initPool (pImpl))
{
rtl_freeZeroMemory (pImpl, sizeof(RandomPool_Impl));
pImpl = (RandomPool_Impl*)NULL;
}
}
return ((rtlRandomPool)pImpl);
}
/*
* rtl_random_destroyPool.
*/
void SAL_CALL rtl_random_destroyPool (rtlRandomPool Pool)
{
RandomPool_Impl *pImpl = (RandomPool_Impl *)Pool;
if (pImpl)
{
rtl_digest_destroy (pImpl->m_hDigest);
rtl_freeZeroMemory (pImpl, sizeof (RandomPool_Impl));
}
}
/*
* rtl_random_addBytes.
*/
rtlRandomError SAL_CALL rtl_random_addBytes (
rtlRandomPool Pool, const void *Buffer, sal_Size Bytes)
{
RandomPool_Impl *pImpl = (RandomPool_Impl *)Pool;
const sal_uInt8 *pBuffer = (const sal_uInt8 *)Buffer;
if ((pImpl == NULL) || (pBuffer == NULL))
return rtl_Random_E_Argument;
__rtl_random_seedPool (pImpl, pBuffer, Bytes);
return rtl_Random_E_None;
}
/*
* rtl_random_getBytes.
*/
rtlRandomError SAL_CALL rtl_random_getBytes (
rtlRandomPool Pool, void *Buffer, sal_Size Bytes)
{
RandomPool_Impl *pImpl = (RandomPool_Impl *)Pool;
sal_uInt8 *pBuffer = (sal_uInt8 *)Buffer;
if ((pImpl == NULL) || (pBuffer == NULL))
return rtl_Random_E_Argument;
__rtl_random_readPool (pImpl, pBuffer, Bytes);
return rtl_Random_E_None;
}