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1181 lines
48 KiB
1181 lines
48 KiB
![]()
4 years ago
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// secblock.h - originally written and placed in the public domain by Wei Dai
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/// \file secblock.h
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/// \brief Classes and functions for secure memory allocations.
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#ifndef CRYPTOPP_SECBLOCK_H
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#define CRYPTOPP_SECBLOCK_H
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#include "config.h"
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#include "allocate.h"
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#include "misc.h"
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#include "stdcpp.h"
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#if CRYPTOPP_MSC_VERSION
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# pragma warning(push)
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# pragma warning(disable: 4231 4275 4700)
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# if (CRYPTOPP_MSC_VERSION >= 1400)
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# pragma warning(disable: 6011 6386 28193)
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# endif
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#endif
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NAMESPACE_BEGIN(CryptoPP)
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// ************** secure memory allocation ***************
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/// \brief Base class for all allocators used by SecBlock
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/// \tparam T the class or type
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template<class T>
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class AllocatorBase
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{
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public:
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typedef T value_type;
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typedef size_t size_type;
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typedef std::ptrdiff_t difference_type;
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typedef T * pointer;
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typedef const T * const_pointer;
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typedef T & reference;
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typedef const T & const_reference;
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pointer address(reference r) const {return (&r);}
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const_pointer address(const_reference r) const {return (&r); }
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void construct(pointer p, const T& val) {new (p) T(val);}
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void destroy(pointer p) {CRYPTOPP_UNUSED(p); p->~T();}
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/// \brief Returns the maximum number of elements the allocator can provide
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/// \details <tt>ELEMS_MAX</tt> is the maximum number of elements the
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/// <tt>Allocator</tt> can provide. The value of <tt>ELEMS_MAX</tt> is
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/// <tt>SIZE_MAX/sizeof(T)</tt>. <tt>std::numeric_limits</tt> was avoided
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/// due to lack of <tt>constexpr</tt>-ness in C++03 and below.
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/// \note In C++03 and below <tt>ELEMS_MAX</tt> is a static data member of type
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/// <tt>size_type</tt>. In C++11 and above <tt>ELEMS_MAX</tt> is an <tt>enum</tt>
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/// inheriting from <tt>size_type</tt>. In both cases <tt>ELEMS_MAX</tt> can be
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/// used before objects are fully constructed, and it does not suffer the
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/// limitations of class methods like <tt>max_size</tt>.
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/// \sa <A HREF="http://github.com/weidai11/cryptopp/issues/346">Issue 346/CVE-2016-9939</A>
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/// \since Crypto++ 6.0
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#if defined(CRYPTOPP_DOXYGEN_PROCESSING)
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static const size_type ELEMS_MAX = ...;
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#elif defined(_MSC_VER) && (_MSC_VER <= 1400)
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static const size_type ELEMS_MAX = (~(size_type)0)/sizeof(T);
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#elif defined(CRYPTOPP_CXX11_STRONG_ENUM)
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enum : size_type {ELEMS_MAX = SIZE_MAX/sizeof(T)};
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#else
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static const size_type ELEMS_MAX = SIZE_MAX/sizeof(T);
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#endif
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/// \brief Returns the maximum number of elements the allocator can provide
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/// \returns the maximum number of elements the allocator can provide
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/// \details Internally, preprocessor macros are used rather than std::numeric_limits
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/// because the latter is not a constexpr. Some compilers, like Clang, do not
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/// optimize it well under all circumstances. Compilers like GCC, ICC and MSVC appear
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/// to optimize it well in either form.
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CRYPTOPP_CONSTEXPR size_type max_size() const {return ELEMS_MAX;}
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#if defined(__SUNPRO_CC)
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// https://github.com/weidai11/cryptopp/issues/770
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// and https://stackoverflow.com/q/53999461/608639
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CRYPTOPP_CONSTEXPR size_type max_size(size_type n) const {return SIZE_MAX/n;}
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#endif
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#if defined(CRYPTOPP_CXX11_VARIADIC_TEMPLATES) || defined(CRYPTOPP_DOXYGEN_PROCESSING)
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/// \brief Constructs a new V using variadic arguments
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/// \tparam V the type to be forwarded
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/// \tparam Args the arguments to be forwarded
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/// \param ptr pointer to type V
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/// \param args variadic arguments
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/// \details This is a C++11 feature. It is available when CRYPTOPP_CXX11_VARIADIC_TEMPLATES
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/// is defined. The define is controlled by compiler versions detected in config.h.
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template<typename V, typename... Args>
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void construct(V* ptr, Args&&... args) {::new ((void*)ptr) V(std::forward<Args>(args)...);}
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/// \brief Destroys an V constructed with variadic arguments
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/// \tparam V the type to be forwarded
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/// \details This is a C++11 feature. It is available when CRYPTOPP_CXX11_VARIADIC_TEMPLATES
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/// is defined. The define is controlled by compiler versions detected in config.h.
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template<typename V>
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void destroy(V* ptr) {if (ptr) ptr->~V();}
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#endif
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protected:
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/// \brief Verifies the allocator can satisfy a request based on size
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/// \param size the size of the allocation, in elements
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/// \throws InvalidArgument
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/// \details CheckSize verifies the number of elements requested is valid.
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/// \details If size is greater than max_size(), then InvalidArgument is thrown.
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/// The library throws InvalidArgument if the size is too large to satisfy.
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/// \details Internally, preprocessor macros are used rather than std::numeric_limits
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/// because the latter is not a constexpr. Some compilers, like Clang, do not
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/// optimize it well under all circumstances. Compilers like GCC, ICC and MSVC appear
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/// to optimize it well in either form.
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/// \details The <tt>sizeof(T) != 1</tt> in the condition attempts to help the
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/// compiler optimize the check for byte types. Coverity findings for
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/// CONSTANT_EXPRESSION_RESULT were generated without it. For byte types,
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/// size never exceeded ELEMS_MAX but the code was not removed.
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/// \note size is the count of elements, and not the number of bytes
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static void CheckSize(size_t size)
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{
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// Squash MSC C4100 warning for size. Also see commit 42b7c4ea5673.
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CRYPTOPP_UNUSED(size);
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// C++ throws std::bad_alloc (C++03) or std::bad_array_new_length (C++11) here.
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if (sizeof(T) != 1 && size > ELEMS_MAX)
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throw InvalidArgument("AllocatorBase: requested size would cause integer overflow");
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}
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};
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#define CRYPTOPP_INHERIT_ALLOCATOR_TYPES \
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typedef typename AllocatorBase<T>::value_type value_type;\
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typedef typename AllocatorBase<T>::size_type size_type;\
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typedef typename AllocatorBase<T>::difference_type difference_type;\
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typedef typename AllocatorBase<T>::pointer pointer;\
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typedef typename AllocatorBase<T>::const_pointer const_pointer;\
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typedef typename AllocatorBase<T>::reference reference;\
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typedef typename AllocatorBase<T>::const_reference const_reference;
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/// \brief Reallocation function
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/// \tparam T the class or type
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/// \tparam A the class or type's allocator
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/// \param alloc the allocator
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/// \param oldPtr the previous allocation
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/// \param oldSize the size of the previous allocation
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/// \param newSize the new, requested size
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/// \param preserve flag that indicates if the old allocation should be preserved
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/// \note oldSize and newSize are the count of elements, and not the
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/// number of bytes.
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template <class T, class A>
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typename A::pointer StandardReallocate(A& alloc, T *oldPtr, typename A::size_type oldSize, typename A::size_type newSize, bool preserve)
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{
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// Avoid assert on pointer in reallocate. SecBlock regularly uses NULL
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// pointers rather returning non-NULL 0-sized pointers.
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if (oldSize == newSize)
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return oldPtr;
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if (preserve)
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{
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typename A::pointer newPointer = alloc.allocate(newSize, NULLPTR);
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const typename A::size_type copySize = STDMIN(oldSize, newSize) * sizeof(T);
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if (oldPtr && newPointer)
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memcpy_s(newPointer, copySize, oldPtr, copySize);
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if (oldPtr)
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alloc.deallocate(oldPtr, oldSize);
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return newPointer;
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}
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else
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{
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if (oldPtr)
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alloc.deallocate(oldPtr, oldSize);
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return alloc.allocate(newSize, NULLPTR);
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}
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}
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/// \brief Allocates a block of memory with cleanup
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/// \tparam T class or type
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/// \tparam T_Align16 boolean that determines whether allocations should be aligned on a 16-byte boundary
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/// \details If T_Align16 is true, then AllocatorWithCleanup calls AlignedAllocate()
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/// for memory allocations. If T_Align16 is false, then AllocatorWithCleanup() calls
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/// UnalignedAllocate() for memory allocations.
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/// \details Template parameter T_Align16 is effectively controlled by cryptlib.h and mirrors
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/// CRYPTOPP_BOOL_ALIGN16. CRYPTOPP_BOOL_ALIGN16 is often used as the template parameter.
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template <class T, bool T_Align16 = false>
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class AllocatorWithCleanup : public AllocatorBase<T>
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{
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public:
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CRYPTOPP_INHERIT_ALLOCATOR_TYPES
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/// \brief Allocates a block of memory
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/// \param ptr the size of the allocation
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/// \param size the size of the allocation, in elements
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/// \returns a memory block
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/// \throws InvalidArgument
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/// \details allocate() first checks the size of the request. If it is non-0
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/// and less than max_size(), then an attempt is made to fulfill the request
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/// using either AlignedAllocate() or UnalignedAllocate(). AlignedAllocate() is
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/// used if T_Align16 is true. UnalignedAllocate() used if T_Align16 is false.
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/// \details This is the C++ *Placement New* operator. ptr is not used, and the
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/// function asserts in Debug builds if ptr is non-NULL.
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/// \sa CallNewHandler() for the methods used to recover from a failed
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/// allocation attempt.
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/// \note size is the count of elements, and not the number of bytes
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pointer allocate(size_type size, const void *ptr = NULLPTR)
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{
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CRYPTOPP_UNUSED(ptr); CRYPTOPP_ASSERT(ptr == NULLPTR);
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this->CheckSize(size);
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if (size == 0)
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return NULLPTR;
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#if CRYPTOPP_BOOL_ALIGN16
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if (T_Align16)
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return reinterpret_cast<pointer>(AlignedAllocate(size*sizeof(T)));
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#endif
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return reinterpret_cast<pointer>(UnalignedAllocate(size*sizeof(T)));
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}
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/// \brief Deallocates a block of memory
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/// \param ptr the pointer for the allocation
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/// \param size the size of the allocation, in elements
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/// \details Internally, SecureWipeArray() is called before deallocating the
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/// memory. Once the memory block is wiped or zeroized, AlignedDeallocate()
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/// or UnalignedDeallocate() is called.
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/// \details AlignedDeallocate() is used if T_Align16 is true.
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/// UnalignedDeallocate() used if T_Align16 is false.
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void deallocate(void *ptr, size_type size)
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{
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// Avoid assert on pointer in deallocate. SecBlock regularly uses NULL
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// pointers rather returning non-NULL 0-sized pointers.
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if (ptr)
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{
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SecureWipeArray(reinterpret_cast<pointer>(ptr), size);
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#if CRYPTOPP_BOOL_ALIGN16
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if (T_Align16)
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return AlignedDeallocate(ptr);
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#endif
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UnalignedDeallocate(ptr);
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}
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}
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/// \brief Reallocates a block of memory
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/// \param oldPtr the previous allocation
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/// \param oldSize the size of the previous allocation
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/// \param newSize the new, requested size
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/// \param preserve flag that indicates if the old allocation should be preserved
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/// \returns pointer to the new memory block
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/// \details Internally, reallocate() calls StandardReallocate().
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/// \details If preserve is true, then index 0 is used to begin copying the
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/// old memory block to the new one. If the block grows, then the old array
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/// is copied in its entirety. If the block shrinks, then only newSize
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/// elements are copied from the old block to the new one.
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/// \note oldSize and newSize are the count of elements, and not the
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/// number of bytes.
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pointer reallocate(T *oldPtr, size_type oldSize, size_type newSize, bool preserve)
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{
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CRYPTOPP_ASSERT((oldPtr && oldSize) || !(oldPtr || oldSize));
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return StandardReallocate(*this, oldPtr, oldSize, newSize, preserve);
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}
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/// \brief Template class member Rebind
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/// \tparam V bound class or type
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/// \details Rebind allows a container class to allocate a different type of object
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/// to store elements. For example, a std::list will allocate std::list_node to
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/// store elements in the list.
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/// \details VS.NET STL enforces the policy of "All STL-compliant allocators
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/// have to provide a template class member called rebind".
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template <class V> struct rebind { typedef AllocatorWithCleanup<V, T_Align16> other; };
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#if _MSC_VER >= 1500
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AllocatorWithCleanup() {}
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template <class V, bool A> AllocatorWithCleanup(const AllocatorWithCleanup<V, A> &) {}
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#endif
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};
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<byte>;
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word16>;
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word32>;
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word64>;
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#if defined(CRYPTOPP_WORD128_AVAILABLE)
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word128, true>; // for Integer
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#endif
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#if CRYPTOPP_BOOL_X86
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CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word, true>; // for Integer
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#endif
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/// \brief NULL allocator
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/// \tparam T class or type
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/// \details A NullAllocator is useful for fixed-size, stack based allocations
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/// (i.e., static arrays used by FixedSizeAllocatorWithCleanup).
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/// \details A NullAllocator always returns 0 for max_size(), and always returns
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/// NULL for allocation requests. Though the allocator does not allocate at
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/// runtime, it does perform a secure wipe or zeroization during cleanup.
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template <class T>
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class NullAllocator : public AllocatorBase<T>
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{
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public:
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//LCOV_EXCL_START
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CRYPTOPP_INHERIT_ALLOCATOR_TYPES
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// TODO: should this return NULL or throw bad_alloc? Non-Windows C++ standard
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// libraries always throw. And late mode Windows throws. Early model Windows
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// (circa VC++ 6.0) returned NULL.
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pointer allocate(size_type n, const void* unused = NULLPTR)
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{
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CRYPTOPP_UNUSED(n); CRYPTOPP_UNUSED(unused);
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CRYPTOPP_ASSERT(false); return NULLPTR;
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}
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void deallocate(void *p, size_type n)
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{
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CRYPTOPP_UNUSED(p); CRYPTOPP_UNUSED(n);
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CRYPTOPP_ASSERT(false);
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}
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CRYPTOPP_CONSTEXPR size_type max_size() const {return 0;}
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//LCOV_EXCL_STOP
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};
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/// \brief Static secure memory block with cleanup
|
||
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/// \tparam T class or type
|
||
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/// \tparam S fixed-size of the stack-based memory block, in elements
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/// \tparam T_Align16 boolean that determines whether allocations should
|
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/// be aligned on a 16-byte boundary
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/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
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/// based allocation at compile time. The class can grow its memory
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/// block at runtime if a suitable allocator is available. If size
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/// grows beyond S and a suitable allocator is available, then the
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/// statically allocated array is obsoleted.
|
||
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/// \note This allocator can't be used with standard collections because
|
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/// they require that all objects of the same allocator type are equivalent.
|
||
|
template <class T, size_t S, class A = NullAllocator<T>, bool T_Align16 = false>
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class FixedSizeAllocatorWithCleanup : public AllocatorBase<T>
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{
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||
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// The body of FixedSizeAllocatorWithCleanup is provided in the two
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// partial specializations that follow. The two specialiations
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||
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// pivot on the boolean template parameter T_Align16. AIX, Solaris,
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||
|
// IBM XLC and SunCC receive a little extra help. We managed to
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// clear most of the warnings.
|
||
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};
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||
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|
||
|
/// \brief Static secure memory block with cleanup
|
||
|
/// \tparam T class or type
|
||
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/// \tparam S fixed-size of the stack-based memory block, in elements
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/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
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/// based allocation at compile time. The class can grow its memory
|
||
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/// block at runtime if a suitable allocator is available. If size
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||
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/// grows beyond S and a suitable allocator is available, then the
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||
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/// statically allocated array is obsoleted.
|
||
|
/// \note This allocator can't be used with standard collections because
|
||
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/// they require that all objects of the same allocator type are equivalent.
|
||
|
template <class T, size_t S, class A>
|
||
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class FixedSizeAllocatorWithCleanup<T, S, A, true> : public AllocatorBase<T>
|
||
|
{
|
||
|
public:
|
||
|
CRYPTOPP_INHERIT_ALLOCATOR_TYPES
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||
|
|
||
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/// \brief Constructs a FixedSizeAllocatorWithCleanup
|
||
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FixedSizeAllocatorWithCleanup() : m_allocated(false) {}
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||
|
|
||
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/// \brief Allocates a block of memory
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-based
|
||
|
/// allocation at compile time. If size is less than or equal to
|
||
|
/// <tt>S</tt>, then a pointer to the static array is returned.
|
||
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/// \details The class can grow its memory block at runtime if a suitable
|
||
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/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer allocate(size_type size)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT(IsAlignedOn(m_array, 8));
|
||
|
|
||
|
if (size <= S && !m_allocated)
|
||
|
{
|
||
|
m_allocated = true;
|
||
|
return GetAlignedArray();
|
||
|
}
|
||
|
else
|
||
|
return m_fallbackAllocator.allocate(size);
|
||
|
}
|
||
|
|
||
|
/// \brief Allocates a block of memory
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \param hint an unused hint
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
|
/// based allocation at compile time. If size is less than or equal to
|
||
|
/// S, then a pointer to the static array is returned.
|
||
|
/// \details The class can grow its memory block at runtime if a suitable
|
||
|
/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer allocate(size_type size, const void *hint)
|
||
|
{
|
||
|
if (size <= S && !m_allocated)
|
||
|
{
|
||
|
m_allocated = true;
|
||
|
return GetAlignedArray();
|
||
|
}
|
||
|
else
|
||
|
return m_fallbackAllocator.allocate(size, hint);
|
||
|
}
|
||
|
|
||
|
/// \brief Deallocates a block of memory
|
||
|
/// \param ptr a pointer to the memory block to deallocate
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \details The memory block is wiped or zeroized before deallocation.
|
||
|
/// If the statically allocated memory block is active, then no
|
||
|
/// additional actions are taken after the wipe.
|
||
|
/// \details If a dynamic memory block is active, then the pointer and
|
||
|
/// size are passed to the allocator for deallocation.
|
||
|
void deallocate(void *ptr, size_type size)
|
||
|
{
|
||
|
// Avoid assert on pointer in deallocate. SecBlock regularly uses NULL
|
||
|
// pointers rather returning non-NULL 0-sized pointers.
|
||
|
if (ptr == GetAlignedArray())
|
||
|
{
|
||
|
// If the m_allocated assert fires then the bit twiddling for
|
||
|
// GetAlignedArray() is probably incorrect for the platform.
|
||
|
// Be sure to check CRYPTOPP_ALIGN_DATA(8). The platform may
|
||
|
// not have a way to declaritively align data to 8.
|
||
|
CRYPTOPP_ASSERT(size <= S);
|
||
|
CRYPTOPP_ASSERT(m_allocated);
|
||
|
m_allocated = false;
|
||
|
SecureWipeArray(reinterpret_cast<pointer>(ptr), size);
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
if (ptr)
|
||
|
m_fallbackAllocator.deallocate(ptr, size);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// \brief Reallocates a block of memory
|
||
|
/// \param oldPtr the previous allocation
|
||
|
/// \param oldSize the size of the previous allocation
|
||
|
/// \param newSize the new, requested size
|
||
|
/// \param preserve flag that indicates if the old allocation should
|
||
|
/// be preserved
|
||
|
/// \returns pointer to the new memory block
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
|
/// based allocation at compile time. If size is less than or equal to
|
||
|
/// S, then a pointer to the static array is returned.
|
||
|
/// \details The class can grow its memory block at runtime if a suitable
|
||
|
/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \note size is the count of elements, and not the number of bytes.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer reallocate(pointer oldPtr, size_type oldSize, size_type newSize, bool preserve)
|
||
|
{
|
||
|
if (oldPtr == GetAlignedArray() && newSize <= S)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT(oldSize <= S);
|
||
|
if (oldSize > newSize)
|
||
|
SecureWipeArray(oldPtr+newSize, oldSize-newSize);
|
||
|
return oldPtr;
|
||
|
}
|
||
|
|
||
|
pointer newPointer = allocate(newSize, NULLPTR);
|
||
|
if (preserve && newSize)
|
||
|
{
|
||
|
const size_type copySize = STDMIN(oldSize, newSize);
|
||
|
if (newPointer && oldPtr) // GCC analyzer warning
|
||
|
memcpy_s(newPointer, sizeof(T)*newSize, oldPtr, sizeof(T)*copySize);
|
||
|
}
|
||
|
deallocate(oldPtr, oldSize);
|
||
|
return newPointer;
|
||
|
}
|
||
|
|
||
|
CRYPTOPP_CONSTEXPR size_type max_size() const
|
||
|
{
|
||
|
return STDMAX(m_fallbackAllocator.max_size(), S);
|
||
|
}
|
||
|
|
||
|
private:
|
||
|
|
||
|
#if defined(CRYPTOPP_BOOL_ALIGN16) && (defined(_M_X64) || defined(__x86_64__))
|
||
|
// Before we can add additional platforms we need to check the
|
||
|
// linker documentation for alignment behavior for stack variables.
|
||
|
// CRYPTOPP_ALIGN_DATA(16) is known OK on Linux, OS X, Solaris.
|
||
|
// Also see http://stackoverflow.com/a/1468656/608639.
|
||
|
T* GetAlignedArray() {
|
||
|
CRYPTOPP_ASSERT(IsAlignedOn(m_array, 16));
|
||
|
return m_array;
|
||
|
}
|
||
|
CRYPTOPP_ALIGN_DATA(16) T m_array[S];
|
||
|
|
||
|
#elif defined(CRYPTOPP_BOOL_ALIGN16)
|
||
|
|
||
|
// There be demons here... We cannot use CRYPTOPP_ALIGN_DATA(16)
|
||
|
// because linkers on 32-bit machines (and some 64-bit machines)
|
||
|
// align the stack to 8-bytes or less by default, not 16-bytes as
|
||
|
// requested. Additionally, the AIX linker seems to use 4-bytes
|
||
|
// by default. However, all linkers tested appear to honor
|
||
|
// CRYPTOPP_ALIGN_DATA(8). Also see
|
||
|
// http://stackoverflow.com/a/1468656/608639.
|
||
|
//
|
||
|
// The 16-byte alignment is achieved by padding the requested
|
||
|
// size with extra elements so we have at least 16-bytes of slack
|
||
|
// to work with. Then the pointer is moved down to achieve a
|
||
|
// 16-byte alignment (stacks grow down).
|
||
|
//
|
||
|
// The additional 16-bytes introduces a small secondary issue.
|
||
|
// The secondary issue is, a large T results in 0 = 8/sizeof(T).
|
||
|
// The library is OK but users may hit it. So we need to guard
|
||
|
// for a large T, and that is what PAD achieves.
|
||
|
T* GetAlignedArray() {
|
||
|
T* p_array = reinterpret_cast<T*>(static_cast<void*>((reinterpret_cast<byte*>(m_array)) + (0-reinterpret_cast<size_t>(m_array))%16));
|
||
|
// Verify the 16-byte alignment
|
||
|
CRYPTOPP_ASSERT(IsAlignedOn(p_array, 16));
|
||
|
// Verify allocated array with pad is large enough.
|
||
|
CRYPTOPP_ASSERT(p_array+S <= m_array+(S+PAD));
|
||
|
return p_array;
|
||
|
}
|
||
|
|
||
|
# if defined(_AIX)
|
||
|
// PAD is elements, not bytes, and rounded up to ensure no overflow.
|
||
|
enum { Q = sizeof(T), PAD = (Q >= 16) ? 1 : (Q >= 8) ? 2 : (Q >= 4) ? 4 : (Q >= 2) ? 8 : 16 };
|
||
|
CRYPTOPP_ALIGN_DATA(8) T m_array[S+PAD];
|
||
|
# else
|
||
|
// PAD is elements, not bytes, and rounded up to ensure no overflow.
|
||
|
enum { Q = sizeof(T), PAD = (Q >= 8) ? 1 : (Q >= 4) ? 2 : (Q >= 2) ? 4 : 8 };
|
||
|
CRYPTOPP_ALIGN_DATA(8) T m_array[S+PAD];
|
||
|
# endif
|
||
|
|
||
|
#else
|
||
|
|
||
|
// CRYPTOPP_BOOL_ALIGN16 is 0. Use natural alignment of T.
|
||
|
T* GetAlignedArray() {return m_array;}
|
||
|
CRYPTOPP_ALIGN_DATA(4) T m_array[S];
|
||
|
|
||
|
#endif
|
||
|
|
||
|
A m_fallbackAllocator;
|
||
|
bool m_allocated;
|
||
|
};
|
||
|
|
||
|
/// \brief Static secure memory block with cleanup
|
||
|
/// \tparam T class or type
|
||
|
/// \tparam S fixed-size of the stack-based memory block, in elements
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
|
/// based allocation at compile time. The class can grow its memory
|
||
|
/// block at runtime if a suitable allocator is available. If size
|
||
|
/// grows beyond S and a suitable allocator is available, then the
|
||
|
/// statically allocated array is obsoleted.
|
||
|
/// \note This allocator can't be used with standard collections because
|
||
|
/// they require that all objects of the same allocator type are equivalent.
|
||
|
template <class T, size_t S, class A>
|
||
|
class FixedSizeAllocatorWithCleanup<T, S, A, false> : public AllocatorBase<T>
|
||
|
{
|
||
|
public:
|
||
|
CRYPTOPP_INHERIT_ALLOCATOR_TYPES
|
||
|
|
||
|
/// \brief Constructs a FixedSizeAllocatorWithCleanup
|
||
|
FixedSizeAllocatorWithCleanup() : m_allocated(false) {}
|
||
|
|
||
|
/// \brief Allocates a block of memory
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-based
|
||
|
/// allocation at compile time. If size is less than or equal to
|
||
|
/// <tt>S</tt>, then a pointer to the static array is returned.
|
||
|
/// \details The class can grow its memory block at runtime if a suitable
|
||
|
/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer allocate(size_type size)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT(IsAlignedOn(m_array, 8));
|
||
|
|
||
|
if (size <= S && !m_allocated)
|
||
|
{
|
||
|
m_allocated = true;
|
||
|
return GetAlignedArray();
|
||
|
}
|
||
|
else
|
||
|
return m_fallbackAllocator.allocate(size);
|
||
|
}
|
||
|
|
||
|
/// \brief Allocates a block of memory
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \param hint an unused hint
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
|
/// based allocation at compile time. If size is less than or equal to
|
||
|
/// S, then a pointer to the static array is returned.
|
||
|
/// \details The class can grow its memory block at runtime if a suitable
|
||
|
/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer allocate(size_type size, const void *hint)
|
||
|
{
|
||
|
if (size <= S && !m_allocated)
|
||
|
{
|
||
|
m_allocated = true;
|
||
|
return GetAlignedArray();
|
||
|
}
|
||
|
else
|
||
|
return m_fallbackAllocator.allocate(size, hint);
|
||
|
}
|
||
|
|
||
|
/// \brief Deallocates a block of memory
|
||
|
/// \param ptr a pointer to the memory block to deallocate
|
||
|
/// \param size the count elements in the memory block
|
||
|
/// \details The memory block is wiped or zeroized before deallocation.
|
||
|
/// If the statically allocated memory block is active, then no
|
||
|
/// additional actions are taken after the wipe.
|
||
|
/// \details If a dynamic memory block is active, then the pointer and
|
||
|
/// size are passed to the allocator for deallocation.
|
||
|
void deallocate(void *ptr, size_type size)
|
||
|
{
|
||
|
// Avoid assert on pointer in deallocate. SecBlock regularly uses NULL
|
||
|
// pointers rather returning non-NULL 0-sized pointers.
|
||
|
if (ptr == GetAlignedArray())
|
||
|
{
|
||
|
// If the m_allocated assert fires then
|
||
|
// something overwrote the flag.
|
||
|
CRYPTOPP_ASSERT(size <= S);
|
||
|
CRYPTOPP_ASSERT(m_allocated);
|
||
|
m_allocated = false;
|
||
|
SecureWipeArray((pointer)ptr, size);
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
if (ptr)
|
||
|
m_fallbackAllocator.deallocate(ptr, size);
|
||
|
m_allocated = false;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/// \brief Reallocates a block of memory
|
||
|
/// \param oldPtr the previous allocation
|
||
|
/// \param oldSize the size of the previous allocation
|
||
|
/// \param newSize the new, requested size
|
||
|
/// \param preserve flag that indicates if the old allocation should
|
||
|
/// be preserved
|
||
|
/// \returns pointer to the new memory block
|
||
|
/// \details FixedSizeAllocatorWithCleanup provides a fixed-size, stack-
|
||
|
/// based allocation at compile time. If size is less than or equal to
|
||
|
/// S, then a pointer to the static array is returned.
|
||
|
/// \details The class can grow its memory block at runtime if a suitable
|
||
|
/// allocator is available. If size grows beyond S and a suitable
|
||
|
/// allocator is available, then the statically allocated array is
|
||
|
/// obsoleted. If a suitable allocator is not available, as with a
|
||
|
/// NullAllocator, then the function returns NULL and a runtime error
|
||
|
/// eventually occurs.
|
||
|
/// \note size is the count of elements, and not the number of bytes.
|
||
|
/// \sa reallocate(), SecBlockWithHint
|
||
|
pointer reallocate(pointer oldPtr, size_type oldSize, size_type newSize, bool preserve)
|
||
|
{
|
||
|
if (oldPtr == GetAlignedArray() && newSize <= S)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT(oldSize <= S);
|
||
|
if (oldSize > newSize)
|
||
|
SecureWipeArray(oldPtr+newSize, oldSize-newSize);
|
||
|
return oldPtr;
|
||
|
}
|
||
|
|
||
|
pointer newPointer = allocate(newSize, NULLPTR);
|
||
|
if (preserve && newSize)
|
||
|
{
|
||
|
const size_type copySize = STDMIN(oldSize, newSize);
|
||
|
if (newPointer && oldPtr) // GCC analyzer warning
|
||
|
memcpy_s(newPointer, sizeof(T)*newSize, oldPtr, sizeof(T)*copySize);
|
||
|
}
|
||
|
deallocate(oldPtr, oldSize);
|
||
|
return newPointer;
|
||
|
}
|
||
|
|
||
|
CRYPTOPP_CONSTEXPR size_type max_size() const
|
||
|
{
|
||
|
return STDMAX(m_fallbackAllocator.max_size(), S);
|
||
|
}
|
||
|
|
||
|
private:
|
||
|
|
||
|
// The 8-byte alignments follows convention of Linux and Windows.
|
||
|
// Linux and Windows receives most testing. Duplicate it here for
|
||
|
// other platforms like AIX and Solaris. AIX and Solaris often use
|
||
|
// alignments smaller than expected. In fact AIX caught us by
|
||
|
// surprise with word16 and word32.
|
||
|
T* GetAlignedArray() {return m_array;}
|
||
|
CRYPTOPP_ALIGN_DATA(8) T m_array[S];
|
||
|
|
||
|
A m_fallbackAllocator;
|
||
|
bool m_allocated;
|
||
|
};
|
||
|
|
||
|
/// \brief Secure memory block with allocator and cleanup
|
||
|
/// \tparam T a class or type
|
||
|
/// \tparam A AllocatorWithCleanup derived class for allocation and cleanup
|
||
|
template <class T, class A = AllocatorWithCleanup<T> >
|
||
|
class SecBlock
|
||
|
{
|
||
|
public:
|
||
|
typedef typename A::value_type value_type;
|
||
|
typedef typename A::pointer iterator;
|
||
|
typedef typename A::const_pointer const_iterator;
|
||
|
typedef typename A::size_type size_type;
|
||
|
|
||
|
/// \brief Returns the maximum number of elements the block can hold
|
||
|
/// \details <tt>ELEMS_MAX</tt> is the maximum number of elements the
|
||
|
/// <tt>SecBlock</tt> can hold. The value of <tt>ELEMS_MAX</tt> is
|
||
|
/// <tt>SIZE_MAX/sizeof(T)</tt>. <tt>std::numeric_limits</tt> was avoided
|
||
|
/// due to lack of <tt>constexpr</tt>-ness in C++03 and below.
|
||
|
/// \note In C++03 and below <tt>ELEMS_MAX</tt> is a static data member of type
|
||
|
/// <tt>size_type</tt>. In C++11 and above <tt>ELEMS_MAX</tt> is an <tt>enum</tt>
|
||
|
/// inheriting from <tt>size_type</tt>. In both cases <tt>ELEMS_MAX</tt> can be
|
||
|
/// used before objects are fully constructed, and it does not suffer the
|
||
|
/// limitations of class methods like <tt>max_size</tt>.
|
||
|
/// \sa <A HREF="http://github.com/weidai11/cryptopp/issues/346">Issue 346/CVE-2016-9939</A>
|
||
|
/// \since Crypto++ 6.0
|
||
|
#if defined(CRYPTOPP_DOXYGEN_PROCESSING)
|
||
|
static const size_type ELEMS_MAX = ...;
|
||
|
#elif defined(_MSC_VER) && (_MSC_VER <= 1400)
|
||
|
static const size_type ELEMS_MAX = (~(size_type)0)/sizeof(T);
|
||
|
#elif defined(CRYPTOPP_CXX11_STRONG_ENUM)
|
||
|
enum : size_type {ELEMS_MAX = A::ELEMS_MAX};
|
||
|
#else
|
||
|
static const size_type ELEMS_MAX = SIZE_MAX/sizeof(T);
|
||
|
#endif
|
||
|
|
||
|
/// \brief Construct a SecBlock with space for size elements.
|
||
|
/// \param size the size of the allocation, in elements
|
||
|
/// \throws std::bad_alloc
|
||
|
/// \details The elements are not initialized.
|
||
|
/// \note size is the count of elements, and not the number of bytes
|
||
|
explicit SecBlock(size_type size=0)
|
||
|
: m_mark(ELEMS_MAX), m_size(size), m_ptr(m_alloc.allocate(size, NULLPTR)) { }
|
||
|
|
||
|
/// \brief Copy construct a SecBlock from another SecBlock
|
||
|
/// \param t the other SecBlock
|
||
|
/// \throws std::bad_alloc
|
||
|
SecBlock(const SecBlock<T, A> &t)
|
||
|
: m_mark(t.m_mark), m_size(t.m_size), m_ptr(m_alloc.allocate(t.m_size, NULLPTR)) {
|
||
|
CRYPTOPP_ASSERT((!t.m_ptr && !m_size) || (t.m_ptr && m_size));
|
||
|
if (m_ptr && t.m_ptr)
|
||
|
memcpy_s(m_ptr, m_size*sizeof(T), t.m_ptr, t.m_size*sizeof(T));
|
||
|
}
|
||
|
|
||
|
/// \brief Construct a SecBlock from an array of elements.
|
||
|
/// \param ptr a pointer to an array of T
|
||
|
/// \param len the number of elements in the memory block
|
||
|
/// \throws std::bad_alloc
|
||
|
/// \details If <tt>ptr!=NULL</tt> and <tt>len!=0</tt>, then the block is initialized from the pointer
|
||
|
/// <tt>ptr</tt>. If <tt>ptr==NULL</tt> and <tt>len!=0</tt>, then the block is initialized to 0.
|
||
|
/// Otherwise, the block is empty and not initialized.
|
||
|
/// \note size is the count of elements, and not the number of bytes
|
||
|
SecBlock(const T *ptr, size_type len)
|
||
|
: m_mark(ELEMS_MAX), m_size(len), m_ptr(m_alloc.allocate(len, NULLPTR)) {
|
||
|
CRYPTOPP_ASSERT((!m_ptr && !m_size) || (m_ptr && m_size));
|
||
|
if (m_ptr && ptr)
|
||
|
memcpy_s(m_ptr, m_size*sizeof(T), ptr, len*sizeof(T));
|
||
|
else if (m_ptr && m_size)
|
||
|
memset(m_ptr, 0, m_size*sizeof(T));
|
||
|
}
|
||
|
|
||
|
~SecBlock()
|
||
|
{m_alloc.deallocate(m_ptr, STDMIN(m_size, m_mark));}
|
||
|
|
||
|
#ifdef __BORLANDC__
|
||
|
/// \brief Cast operator
|
||
|
/// \returns block pointer cast to non-const <tt>T *</tt>
|
||
|
operator T *() const
|
||
|
{return (T*)m_ptr;}
|
||
|
#else
|
||
|
/// \brief Cast operator
|
||
|
/// \returns block pointer cast to <tt>const void *</tt>
|
||
|
operator const void *() const
|
||
|
{return m_ptr;}
|
||
|
|
||
|
/// \brief Cast operator
|
||
|
/// \returns block pointer cast to non-const <tt>void *</tt>
|
||
|
operator void *()
|
||
|
{return m_ptr;}
|
||
|
|
||
|
/// \brief Cast operator
|
||
|
/// \returns block pointer cast to <tt>const T *</tt>
|
||
|
operator const T *() const
|
||
|
{return m_ptr;}
|
||
|
|
||
|
/// \brief Cast operator
|
||
|
/// \returns block pointer cast to non-const <tt>T *</tt>
|
||
|
operator T *()
|
||
|
{return m_ptr;}
|
||
|
#endif
|
||
|
|
||
|
/// \brief Provides an iterator pointing to the first element in the memory block
|
||
|
/// \returns iterator pointing to the first element in the memory block
|
||
|
iterator begin()
|
||
|
{return m_ptr;}
|
||
|
/// \brief Provides a constant iterator pointing to the first element in the memory block
|
||
|
/// \returns constant iterator pointing to the first element in the memory block
|
||
|
const_iterator begin() const
|
||
|
{return m_ptr;}
|
||
|
/// \brief Provides an iterator pointing beyond the last element in the memory block
|
||
|
/// \returns iterator pointing beyond the last element in the memory block
|
||
|
iterator end()
|
||
|
{return m_ptr+m_size;}
|
||
|
/// \brief Provides a constant iterator pointing beyond the last element in the memory block
|
||
|
/// \returns constant iterator pointing beyond the last element in the memory block
|
||
|
const_iterator end() const
|
||
|
{return m_ptr+m_size;}
|
||
|
|
||
|
/// \brief Provides a pointer to the first element in the memory block
|
||
|
/// \returns pointer to the first element in the memory block
|
||
|
typename A::pointer data() {return m_ptr;}
|
||
|
/// \brief Provides a pointer to the first element in the memory block
|
||
|
/// \returns constant pointer to the first element in the memory block
|
||
|
typename A::const_pointer data() const {return m_ptr;}
|
||
|
|
||
|
/// \brief Provides the count of elements in the SecBlock
|
||
|
/// \returns number of elements in the memory block
|
||
|
/// \note the return value is the count of elements, and not the number of bytes
|
||
|
size_type size() const {return m_size;}
|
||
|
/// \brief Determines if the SecBlock is empty
|
||
|
/// \returns true if number of elements in the memory block is 0, false otherwise
|
||
|
bool empty() const {return m_size == 0;}
|
||
|
|
||
|
/// \brief Provides a byte pointer to the first element in the memory block
|
||
|
/// \returns byte pointer to the first element in the memory block
|
||
|
byte * BytePtr() {return (byte *)m_ptr;}
|
||
|
/// \brief Return a byte pointer to the first element in the memory block
|
||
|
/// \returns constant byte pointer to the first element in the memory block
|
||
|
const byte * BytePtr() const {return (const byte *)m_ptr;}
|
||
|
/// \brief Provides the number of bytes in the SecBlock
|
||
|
/// \return the number of bytes in the memory block
|
||
|
/// \note the return value is the number of bytes, and not count of elements.
|
||
|
size_type SizeInBytes() const {return m_size*sizeof(T);}
|
||
|
|
||
|
/// \brief Sets the number of elements to zeroize
|
||
|
/// \param count the number of elements
|
||
|
/// \details SetMark is a remediation for Issue 346/CVE-2016-9939 while
|
||
|
/// preserving the streaming interface. The <tt>count</tt> controls the number of
|
||
|
/// elements zeroized, which can be less than <tt>size</tt> or 0.
|
||
|
/// \details An internal variable, <tt>m_mark</tt>, is initialized to the maximum number
|
||
|
/// of elements. The maximum number of elements is <tt>ELEMS_MAX</tt>. Deallocation
|
||
|
/// triggers a zeroization, and the number of elements zeroized is
|
||
|
/// <tt>STDMIN(m_size, m_mark)</tt>. After zeroization, the memory is returned to the
|
||
|
/// system.
|
||
|
/// \details The ASN.1 decoder uses SetMark() to set the element count to 0
|
||
|
/// before throwing an exception. In this case, the attacker provides a large
|
||
|
/// BER encoded length (say 64MB) but only a small number of content octets
|
||
|
/// (say 16). If the allocator zeroized all 64MB, then a transient DoS could
|
||
|
/// occur as CPU cycles are spent zeroizing unintialized memory.
|
||
|
/// \details Generally speaking, any operation which changes the size of the SecBlock
|
||
|
/// results in the mark being reset to <tt>ELEMS_MAX</tt>. In particular, if Assign(),
|
||
|
/// New(), Grow(), CleanNew(), CleanGrow() are called, then the count is reset to
|
||
|
/// <tt>ELEMS_MAX</tt>. The list is not exhaustive.
|
||
|
/// \since Crypto++ 6.0
|
||
|
/// \sa <A HREF="http://github.com/weidai11/cryptopp/issues/346">Issue 346/CVE-2016-9939</A>
|
||
|
void SetMark(size_t count) {m_mark = count;}
|
||
|
|
||
|
/// \brief Set contents and size from an array
|
||
|
/// \param ptr a pointer to an array of T
|
||
|
/// \param len the number of elements in the memory block
|
||
|
/// \details If the memory block is reduced in size, then the reclaimed memory is set to 0.
|
||
|
/// Assign() resets the element count after the previous block is zeroized.
|
||
|
void Assign(const T *ptr, size_type len)
|
||
|
{
|
||
|
New(len);
|
||
|
if (m_ptr && ptr) // GCC analyzer warning
|
||
|
memcpy_s(m_ptr, m_size*sizeof(T), ptr, len*sizeof(T));
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Set contents from a value
|
||
|
/// \param count the number of values to copy
|
||
|
/// \param value the value, repeated count times
|
||
|
/// \details If the memory block is reduced in size, then the reclaimed memory is set to 0.
|
||
|
/// Assign() resets the element count after the previous block is zeroized.
|
||
|
void Assign(size_type count, T value)
|
||
|
{
|
||
|
New(count);
|
||
|
for (size_t i=0; i<count; ++i)
|
||
|
m_ptr[i] = value;
|
||
|
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Copy contents from another SecBlock
|
||
|
/// \param t the other SecBlock
|
||
|
/// \details Assign checks for self assignment.
|
||
|
/// \details If the memory block is reduced in size, then the reclaimed memory is set to 0.
|
||
|
/// If an assignment occurs, then Assign() resets the element count after the previous block
|
||
|
/// is zeroized.
|
||
|
void Assign(const SecBlock<T, A> &t)
|
||
|
{
|
||
|
if (this != &t)
|
||
|
{
|
||
|
New(t.m_size);
|
||
|
if (m_ptr && t.m_ptr) // GCC analyzer warning
|
||
|
memcpy_s(m_ptr, m_size*sizeof(T), t, t.m_size*sizeof(T));
|
||
|
}
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Assign contents from another SecBlock
|
||
|
/// \param t the other SecBlock
|
||
|
/// \details Internally, operator=() calls Assign().
|
||
|
/// \details If the memory block is reduced in size, then the reclaimed memory is set to 0.
|
||
|
/// If an assignment occurs, then Assign() resets the element count after the previous block
|
||
|
/// is zeroized.
|
||
|
SecBlock<T, A>& operator=(const SecBlock<T, A> &t)
|
||
|
{
|
||
|
// Assign guards for self-assignment
|
||
|
Assign(t);
|
||
|
return *this;
|
||
|
}
|
||
|
|
||
|
/// \brief Append contents from another SecBlock
|
||
|
/// \param t the other SecBlock
|
||
|
/// \details Internally, this SecBlock calls Grow and then appends t.
|
||
|
SecBlock<T, A>& operator+=(const SecBlock<T, A> &t)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT((!t.m_ptr && !t.m_size) || (t.m_ptr && t.m_size));
|
||
|
if (t.m_size)
|
||
|
{
|
||
|
const size_type oldSize = m_size;
|
||
|
if (this != &t) // s += t
|
||
|
{
|
||
|
Grow(m_size+t.m_size);
|
||
|
if (m_ptr && t.m_ptr) // GCC analyzer warning
|
||
|
memcpy_s(m_ptr+oldSize, (m_size-oldSize)*sizeof(T), t.m_ptr, t.m_size*sizeof(T));
|
||
|
}
|
||
|
else // t += t
|
||
|
{
|
||
|
Grow(m_size*2);
|
||
|
if (m_ptr && t.m_ptr) // GCC analyzer warning
|
||
|
memcpy_s(m_ptr+oldSize, (m_size-oldSize)*sizeof(T), m_ptr, oldSize*sizeof(T));
|
||
|
}
|
||
|
}
|
||
|
m_mark = ELEMS_MAX;
|
||
|
return *this;
|
||
|
}
|
||
|
|
||
|
/// \brief Construct a SecBlock from this and another SecBlock
|
||
|
/// \param t the other SecBlock
|
||
|
/// \returns a newly constructed SecBlock that is a conacentation of this and t
|
||
|
/// \details Internally, a new SecBlock is created from this and a concatenation of t.
|
||
|
SecBlock<T, A> operator+(const SecBlock<T, A> &t)
|
||
|
{
|
||
|
CRYPTOPP_ASSERT((!m_ptr && !m_size) || (m_ptr && m_size));
|
||
|
CRYPTOPP_ASSERT((!t.m_ptr && !t.m_size) || (t.m_ptr && t.m_size));
|
||
|
if(!t.m_size) return SecBlock(*this);
|
||
|
|
||
|
SecBlock<T, A> result(m_size+t.m_size);
|
||
|
if (m_size)
|
||
|
memcpy_s(result.m_ptr, result.m_size*sizeof(T), m_ptr, m_size*sizeof(T));
|
||
|
if (result.m_ptr && t.m_ptr) // GCC analyzer warning
|
||
|
memcpy_s(result.m_ptr+m_size, (result.m_size-m_size)*sizeof(T), t.m_ptr, t.m_size*sizeof(T));
|
||
|
return result;
|
||
|
}
|
||
|
|
||
|
/// \brief Bitwise compare two SecBlocks
|
||
|
/// \param t the other SecBlock
|
||
|
/// \returns true if the size and bits are equal, false otherwise
|
||
|
/// \details Uses a constant time compare if the arrays are equal size. The constant time
|
||
|
/// compare is VerifyBufsEqual() found in misc.h.
|
||
|
/// \sa operator!=()
|
||
|
bool operator==(const SecBlock<T, A> &t) const
|
||
|
{
|
||
|
return m_size == t.m_size && VerifyBufsEqual(
|
||
|
reinterpret_cast<const byte*>(m_ptr),
|
||
|
reinterpret_cast<const byte*>(t.m_ptr), m_size*sizeof(T));
|
||
|
}
|
||
|
|
||
|
/// \brief Bitwise compare two SecBlocks
|
||
|
/// \param t the other SecBlock
|
||
|
/// \returns true if the size and bits are equal, false otherwise
|
||
|
/// \details Uses a constant time compare if the arrays are equal size. The constant time
|
||
|
/// compare is VerifyBufsEqual() found in misc.h.
|
||
|
/// \details Internally, operator!=() returns the inverse of operator==().
|
||
|
/// \sa operator==()
|
||
|
bool operator!=(const SecBlock<T, A> &t) const
|
||
|
{
|
||
|
return !operator==(t);
|
||
|
}
|
||
|
|
||
|
/// \brief Change size without preserving contents
|
||
|
/// \param newSize the new size of the memory block
|
||
|
/// \details Old content is not preserved. If the memory block is reduced in size,
|
||
|
/// then the reclaimed memory is set to 0. If the memory block grows in size, then
|
||
|
/// the new memory is not initialized. New() resets the element count after the
|
||
|
/// previous block is zeroized.
|
||
|
/// \details Internally, this SecBlock calls reallocate().
|
||
|
/// \sa New(), CleanNew(), Grow(), CleanGrow(), resize()
|
||
|
void New(size_type newSize)
|
||
|
{
|
||
|
m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, false);
|
||
|
m_size = newSize;
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Change size without preserving contents
|
||
|
/// \param newSize the new size of the memory block
|
||
|
/// \details Old content is not preserved. If the memory block is reduced in size,
|
||
|
/// then the reclaimed content is set to 0. If the memory block grows in size, then
|
||
|
/// the new memory is initialized to 0. CleanNew() resets the element count after the
|
||
|
/// previous block is zeroized.
|
||
|
/// \details Internally, this SecBlock calls New().
|
||
|
/// \sa New(), CleanNew(), Grow(), CleanGrow(), resize()
|
||
|
void CleanNew(size_type newSize)
|
||
|
{
|
||
|
New(newSize);
|
||
|
if (m_ptr) {memset_z(m_ptr, 0, m_size*sizeof(T));}
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Change size and preserve contents
|
||
|
/// \param newSize the new size of the memory block
|
||
|
/// \details Old content is preserved. New content is not initialized.
|
||
|
/// \details Internally, this SecBlock calls reallocate() when size must increase. If the
|
||
|
/// size does not increase, then Grow() does not take action. If the size must
|
||
|
/// change, then use resize(). Grow() resets the element count after the
|
||
|
/// previous block is zeroized.
|
||
|
/// \sa New(), CleanNew(), Grow(), CleanGrow(), resize()
|
||
|
void Grow(size_type newSize)
|
||
|
{
|
||
|
if (newSize > m_size)
|
||
|
{
|
||
|
m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
|
||
|
m_size = newSize;
|
||
|
}
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Change size and preserve contents
|
||
|
/// \param newSize the new size of the memory block
|
||
|
/// \details Old content is preserved. New content is initialized to 0.
|
||
|
/// \details Internally, this SecBlock calls reallocate() when size must increase. If the
|
||
|
/// size does not increase, then CleanGrow() does not take action. If the size must
|
||
|
/// change, then use resize(). CleanGrow() resets the element count after the
|
||
|
/// previous block is zeroized.
|
||
|
/// \sa New(), CleanNew(), Grow(), CleanGrow(), resize()
|
||
|
void CleanGrow(size_type newSize)
|
||
|
{
|
||
|
if (newSize > m_size)
|
||
|
{
|
||
|
m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
|
||
|
memset_z(m_ptr+m_size, 0, (newSize-m_size)*sizeof(T));
|
||
|
m_size = newSize;
|
||
|
}
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Change size and preserve contents
|
||
|
/// \param newSize the new size of the memory block
|
||
|
/// \details Old content is preserved. If the memory block grows in size, then
|
||
|
/// new memory is not initialized. resize() resets the element count after
|
||
|
/// the previous block is zeroized.
|
||
|
/// \details Internally, this SecBlock calls reallocate().
|
||
|
/// \sa New(), CleanNew(), Grow(), CleanGrow(), resize()
|
||
|
void resize(size_type newSize)
|
||
|
{
|
||
|
m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
|
||
|
m_size = newSize;
|
||
|
m_mark = ELEMS_MAX;
|
||
|
}
|
||
|
|
||
|
/// \brief Swap contents with another SecBlock
|
||
|
/// \param b the other SecBlock
|
||
|
/// \details Internally, std::swap() is called on m_alloc, m_size and m_ptr.
|
||
|
void swap(SecBlock<T, A> &b)
|
||
|
{
|
||
|
// Swap must occur on the allocator in case its FixedSize that spilled into the heap.
|
||
|
std::swap(m_alloc, b.m_alloc);
|
||
|
std::swap(m_mark, b.m_mark);
|
||
|
std::swap(m_size, b.m_size);
|
||
|
std::swap(m_ptr, b.m_ptr);
|
||
|
}
|
||
|
|
||
|
protected:
|
||
|
A m_alloc;
|
||
|
size_type m_mark, m_size;
|
||
|
T *m_ptr;
|
||
|
};
|
||
|
|
||
|
#ifdef CRYPTOPP_DOXYGEN_PROCESSING
|
||
|
/// \brief \ref SecBlock "SecBlock<byte>" typedef.
|
||
|
class SecByteBlock : public SecBlock<byte> {};
|
||
|
/// \brief \ref SecBlock "SecBlock<word>" typedef.
|
||
|
class SecWordBlock : public SecBlock<word> {};
|
||
|
/// \brief SecBlock using \ref AllocatorWithCleanup "AllocatorWithCleanup<byte, true>" typedef
|
||
|
class AlignedSecByteBlock : public SecBlock<byte, AllocatorWithCleanup<byte, true> > {};
|
||
|
#else
|
||
|
typedef SecBlock<byte> SecByteBlock;
|
||
|
typedef SecBlock<word> SecWordBlock;
|
||
|
typedef SecBlock<byte, AllocatorWithCleanup<byte, true> > AlignedSecByteBlock;
|
||
|
#endif
|
||
|
|
||
|
// No need for move semantics on derived class *if* the class does not add any
|
||
|
// data members; see http://stackoverflow.com/q/31755703, and Rule of {0|3|5}.
|
||
|
|
||
|
/// \brief Fixed size stack-based SecBlock
|
||
|
/// \tparam T class or type
|
||
|
/// \tparam S fixed-size of the stack-based memory block, in elements
|
||
|
/// \tparam A AllocatorBase derived class for allocation and cleanup
|
||
|
template <class T, unsigned int S, class A = FixedSizeAllocatorWithCleanup<T, S> >
|
||
|
class FixedSizeSecBlock : public SecBlock<T, A>
|
||
|
{
|
||
|
public:
|
||
|
/// \brief Construct a FixedSizeSecBlock
|
||
|
explicit FixedSizeSecBlock() : SecBlock<T, A>(S) {}
|
||
|
};
|
||
|
|
||
|
/// \brief Fixed size stack-based SecBlock with 16-byte alignment
|
||
|
/// \tparam T class or type
|
||
|
/// \tparam S fixed-size of the stack-based memory block, in elements
|
||
|
/// \tparam T_Align16 boolean that determines whether allocations should be aligned on a 16-byte boundary
|
||
|
template <class T, unsigned int S, bool T_Align16 = true>
|
||
|
class FixedSizeAlignedSecBlock : public FixedSizeSecBlock<T, S, FixedSizeAllocatorWithCleanup<T, S, NullAllocator<T>, T_Align16> >
|
||
|
{
|
||
|
};
|
||
|
|
||
|
/// \brief Stack-based SecBlock that grows into the heap
|
||
|
/// \tparam T class or type
|
||
|
/// \tparam S fixed-size of the stack-based memory block, in elements
|
||
|
/// \tparam A AllocatorBase derived class for allocation and cleanup
|
||
|
template <class T, unsigned int S, class A = FixedSizeAllocatorWithCleanup<T, S, AllocatorWithCleanup<T> > >
|
||
|
class SecBlockWithHint : public SecBlock<T, A>
|
||
|
{
|
||
|
public:
|
||
|
/// construct a SecBlockWithHint with a count of elements
|
||
|
explicit SecBlockWithHint(size_t size) : SecBlock<T, A>(size) {}
|
||
|
};
|
||
|
|
||
|
template<class T, bool A, class V, bool B>
|
||
|
inline bool operator==(const CryptoPP::AllocatorWithCleanup<T, A>&, const CryptoPP::AllocatorWithCleanup<V, B>&) {return (true);}
|
||
|
template<class T, bool A, class V, bool B>
|
||
|
inline bool operator!=(const CryptoPP::AllocatorWithCleanup<T, A>&, const CryptoPP::AllocatorWithCleanup<V, B>&) {return (false);}
|
||
|
|
||
|
NAMESPACE_END
|
||
|
|
||
|
NAMESPACE_BEGIN(std)
|
||
|
|
||
|
/// \brief Swap two SecBlocks
|
||
|
/// \tparam T class or type
|
||
|
/// \tparam A AllocatorBase derived class for allocation and cleanup
|
||
|
/// \param a the first SecBlock
|
||
|
/// \param b the second SecBlock
|
||
|
template <class T, class A>
|
||
|
inline void swap(CryptoPP::SecBlock<T, A> &a, CryptoPP::SecBlock<T, A> &b)
|
||
|
{
|
||
|
a.swap(b);
|
||
|
}
|
||
|
|
||
|
#if defined(_STLP_DONT_SUPPORT_REBIND_MEMBER_TEMPLATE) || (defined(_STLPORT_VERSION) && !defined(_STLP_MEMBER_TEMPLATE_CLASSES))
|
||
|
// working for STLport 5.1.3 and MSVC 6 SP5
|
||
|
template <class _Tp1, class _Tp2>
|
||
|
inline CryptoPP::AllocatorWithCleanup<_Tp2>&
|
||
|
__stl_alloc_rebind(CryptoPP::AllocatorWithCleanup<_Tp1>& __a, const _Tp2*)
|
||
|
{
|
||
|
return (CryptoPP::AllocatorWithCleanup<_Tp2>&)(__a);
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
NAMESPACE_END
|
||
|
|
||
|
#if CRYPTOPP_MSC_VERSION
|
||
|
# pragma warning(pop)
|
||
|
#endif
|
||
|
|
||
|
#endif
|