encfs/cipher/MemoryPool.cpp
Valient Gough 95750d4539 begin adding Botan support.
implement pbkdf-hmac-sha256 module for Botan and CommonCrypto.


git-svn-id: http://encfs.googlecode.com/svn/trunk@98 db9cf616-1c43-0410-9cb8-a902689de0d6
2013-03-06 08:02:23 +00:00

150 lines
3.0 KiB
C++

/*****************************************************************************
* Author: Valient Gough <vgough@pobox.com>
*
*****************************************************************************
* Copyright (c) 2003-2013, Valient Gough
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program 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
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "cipher/MemoryPool.h"
#include <cstdlib>
#include <cstring>
#include "base/config.h"
#include "base/Error.h"
#include <pthread.h>
#include <sys/mman.h>
#include <glog/logging.h>
#ifdef HAVE_VALGRIND_MEMCHECK_H
#include <valgrind/memcheck.h>
#else
#define VALGRIND_MAKE_MEM_NOACCESS( a, b )
#define VALGRIND_MAKE_MEM_UNDEFINED( a, b )
#endif
#include <map>
#include <list>
#ifdef WITH_OPENSSL
# include <openssl/crypto.h>
# include <openssl/buffer.h>
#endif
#ifdef WITH_BOTAN
# include <botan/botan.h>
#endif
namespace encfs {
#ifdef WITH_OPENSSL
static byte *allocBlock( int size )
{
byte *block = (byte *)OPENSSL_malloc(size);
return block;
}
static void freeBlock( byte *block, int size )
{
OPENSSL_cleanse(block, size);
OPENSSL_free(block);
}
#else
static byte *allocBlock(int size) {
byte *block = new byte[size];
return block;
}
unsigned char cleanse_ctr = 0;
static void cleanBlock(byte *data, int len) {
byte *p = data;
size_t loop = len, ctr = cleanse_ctr;
while(loop--)
{
*(p++) = (unsigned char)ctr;
ctr += (17 + ((size_t)p & 0xF));
}
// Try to ensure the compiler doesn't optimize away the loop.
p=(byte *)memchr(data, (unsigned char)ctr, len);
if(p)
ctr += (63 + (size_t)p);
cleanse_ctr = (unsigned char)ctr;
}
#endif
void MemBlock::allocate(int size)
{
rAssert(size > 0);
this->data = allocBlock(size);
this->size = size;
}
MemBlock::~MemBlock()
{
cleanBlock(data, size);
delete[] data;
}
SecureMem::SecureMem(int len)
#ifdef WITH_BOTAN
: data_(len)
#endif
{
rAssert(len > 0);
#ifndef WITH_BOTAN
data_ = allocBlock(len);
if (data_)
{
size_ = len;
mlock(data_, size_);
} else
{
size_ = 0;
}
#endif
}
SecureMem::~SecureMem()
{
#ifdef WITH_BOTAN
data_.destroy();
#else
if (size_)
{
cleanBlock(data_, size_);
delete[] data_;
munlock(data_, size_);
data_ = NULL;
size_ = 0;
}
#endif
}
bool operator == (const SecureMem &a, const SecureMem &b) {
return (a.size() == b.size()) &&
(memcmp(a.data(), b.data(), a.size()) == 0);
}
} // namespace encfs