sanitizing_allocator made independent of allocator, as extending the former was not enough to have our deallocate() method called
This commit is contained in:
parent
3c702e03bb
commit
1ce8a004be
@ -737,28 +737,180 @@ namespace winstd
|
||||
///
|
||||
/// @{
|
||||
|
||||
// winstd::sanitizing_allocator::destroy() member generates _Ptr parameter not used warning for primitive datatypes _Ty.
|
||||
#pragma warning(push)
|
||||
#pragma warning(disable: 4100)
|
||||
|
||||
///
|
||||
/// An allocator template that sanitizes each memory block before it is destroyed or reallocated
|
||||
///
|
||||
/// \note
|
||||
/// sanitizing_allocator introduces a performance penalty. However, it provides an additional level of security.
|
||||
/// `sanitizing_allocator` introduces a performance penalty. However, it provides an additional level of security.
|
||||
/// Use for security sensitive data memory storage only.
|
||||
///
|
||||
template <class _Ty>
|
||||
class sanitizing_allocator : public std::allocator<_Ty> {
|
||||
template<class _Ty>
|
||||
class sanitizing_allocator : public std::_Allocator_base<_Ty>
|
||||
{
|
||||
public:
|
||||
typedef std::_Allocator_base<_Ty> _Mybase;
|
||||
typedef typename _Mybase::value_type value_type;
|
||||
|
||||
typedef value_type _FARQ *pointer;
|
||||
typedef value_type _FARQ& reference;
|
||||
typedef const value_type _FARQ *const_pointer;
|
||||
typedef const value_type _FARQ& const_reference;
|
||||
|
||||
typedef _SIZT size_type;
|
||||
typedef _PDFT difference_type;
|
||||
|
||||
|
||||
///
|
||||
/// Sanitizes memory before freeing it
|
||||
/// Convert this type to sanitizing_allocator<_Other>
|
||||
///
|
||||
/// \param[in] p Pointer to heap memory block
|
||||
template<class _Other>
|
||||
struct rebind
|
||||
{
|
||||
typedef sanitizing_allocator<_Other> other;
|
||||
};
|
||||
|
||||
|
||||
///
|
||||
void deallocate(_In_ pointer p, _In_ size_type count)
|
||||
/// Return address of mutable _Val
|
||||
///
|
||||
inline pointer address(_In_ reference _Val) const
|
||||
{
|
||||
return ((pointer) &(char&)_Val);
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Return address of nonmutable _Val
|
||||
///
|
||||
inline const_pointer address(_In_ const_reference _Val) const
|
||||
{
|
||||
return ((const_pointer) &(char&)_Val);
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct default allocator
|
||||
///
|
||||
inline sanitizing_allocator()
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct by copying
|
||||
///
|
||||
inline sanitizing_allocator(_In_ const sanitizing_allocator<_Ty>&)
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct from a related allocator
|
||||
template<class _Other>
|
||||
inline sanitizing_allocator(_In_ const sanitizing_allocator<_Other>&)
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Assign from a related allocator
|
||||
///
|
||||
template<class _Other>
|
||||
inline sanitizing_allocator<_Ty>& operator=(_In_ const sanitizing_allocator<_Other>&)
|
||||
{
|
||||
return (*this);
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Deallocate object at _Ptr sanitizing its content first
|
||||
///
|
||||
inline void deallocate(_In_ pointer _Ptr, _In_ size_type _Count)
|
||||
{
|
||||
// Sanitize then free.
|
||||
SecureZeroMemory(p, sizeof(_Ty)*count);
|
||||
std::allocator<_Ty>::deallocate(p, count);
|
||||
SecureZeroMemory(_Ptr, sizeof(_Ty)*_Count);
|
||||
::operator delete(_Ptr);
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Allocate array of _Count elements
|
||||
///
|
||||
inline pointer allocate(_In_ size_type _Count)
|
||||
{
|
||||
void *_Ptr = 0;
|
||||
|
||||
if (_Count <= 0)
|
||||
_Count = 0;
|
||||
else if (((_SIZT)(-1)/sizeof(_Ty) < _Count) || (_Ptr = ::operator new(_Count * sizeof(_Ty))) == 0)
|
||||
_THROW_NCEE(bad_alloc, 0);
|
||||
|
||||
return ((_Ty _FARQ *)_Ptr);
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Allocate array of _Count elements
|
||||
///
|
||||
inline pointer allocate(_In_ size_type _Count, _In_ const void _FARQ *)
|
||||
{
|
||||
return (allocate(_Count));
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct object at _Ptr with value _Val
|
||||
///
|
||||
inline void construct(_In_ pointer _Ptr, _In_ const _Ty& _Val)
|
||||
{
|
||||
void _FARQ *_Vptr = _Ptr;
|
||||
::new (_Vptr)_Ty1(_STD forward<_Ty2>(_Val));
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct object at _Ptr with value _Val
|
||||
///
|
||||
inline void construct(_In_ pointer _Ptr, _In_ _Ty&& _Val)
|
||||
{
|
||||
::new ((void _FARQ *)_Ptr) _Ty(_STD forward<_Ty>(_Val));
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Construct object at _Ptr with value _Val
|
||||
///
|
||||
template<class _Other>
|
||||
inline void construct(_In_ pointer _Ptr, _In_ _Other&& _Val)
|
||||
{
|
||||
::new ((void _FARQ *)_Ptr) _Ty(_STD forward<_Other>(_Val));
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Destroy object at _Ptr
|
||||
///
|
||||
inline void destroy(_In_ pointer _Ptr)
|
||||
{
|
||||
_Ptr->~_Ty();
|
||||
}
|
||||
|
||||
|
||||
///
|
||||
/// Estimate maximum array size
|
||||
///
|
||||
inline _SIZT max_size() const
|
||||
{
|
||||
_SIZT _Count = (_SIZT)(-1) / sizeof (_Ty);
|
||||
return (0 < _Count ? _Count : 1);
|
||||
}
|
||||
};
|
||||
|
||||
#pragma warning(pop)
|
||||
|
||||
/// @}
|
||||
}
|
||||
|
Loading…
x
Reference in New Issue
Block a user