aboutsummaryrefslogtreecommitdiff
path: root/cryptopp/secblock.h
blob: ca63e43a69f7a1a7b40c248501f2341bebdfe2b9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
// secblock.h - written and placed in the public domain by Wei Dai

#ifndef CRYPTOPP_SECBLOCK_H
#define CRYPTOPP_SECBLOCK_H

#include "config.h"
#include "misc.h"
#include <assert.h>

#if defined(CRYPTOPP_MEMALIGN_AVAILABLE) || defined(CRYPTOPP_MM_MALLOC_AVAILABLE) || defined(QNX)
	#include <malloc.h>
#else
	#include <stdlib.h>
#endif

NAMESPACE_BEGIN(CryptoPP)

// ************** secure memory allocation ***************

template<class T>
class AllocatorBase
{
public:
	typedef T value_type;
	typedef size_t size_type;
#ifdef CRYPTOPP_MSVCRT6
	typedef ptrdiff_t difference_type;
#else
	typedef std::ptrdiff_t difference_type;
#endif
	typedef T * pointer;
	typedef const T * const_pointer;
	typedef T & reference;
	typedef const T & const_reference;

	pointer address(reference r) const {return (&r);}
	const_pointer address(const_reference r) const {return (&r); }
	void construct(pointer p, const T& val) {new (p) T(val);}
	void destroy(pointer p) {p->~T();}
	size_type max_size() const {return ~size_type(0)/sizeof(T);}	// switch to std::numeric_limits<T>::max later

protected:
	static void CheckSize(size_t n)
	{
		if (n > ~size_t(0) / sizeof(T))
			throw InvalidArgument("AllocatorBase: requested size would cause integer overflow");
	}
};

#define CRYPTOPP_INHERIT_ALLOCATOR_TYPES	\
typedef typename AllocatorBase<T>::value_type value_type;\
typedef typename AllocatorBase<T>::size_type size_type;\
typedef typename AllocatorBase<T>::difference_type difference_type;\
typedef typename AllocatorBase<T>::pointer pointer;\
typedef typename AllocatorBase<T>::const_pointer const_pointer;\
typedef typename AllocatorBase<T>::reference reference;\
typedef typename AllocatorBase<T>::const_reference const_reference;

#if defined(_MSC_VER) && (_MSC_VER < 1300)
// this pragma causes an internal compiler error if placed immediately before std::swap(a, b)
#pragma warning(push)
#pragma warning(disable: 4700)	// VC60 workaround: don't know how to get rid of this warning
#endif

template <class T, class A>
typename A::pointer StandardReallocate(A& a, T *p, typename A::size_type oldSize, typename A::size_type newSize, bool preserve)
{
	if (oldSize == newSize)
		return p;

	if (preserve)
	{
		typename A::pointer newPointer = a.allocate(newSize, NULL);
		memcpy_s(newPointer, sizeof(T)*newSize, p, sizeof(T)*STDMIN(oldSize, newSize));
		a.deallocate(p, oldSize);
		return newPointer;
	}
	else
	{
		a.deallocate(p, oldSize);
		return a.allocate(newSize, NULL);
	}
}

#if defined(_MSC_VER) && (_MSC_VER < 1300)
#pragma warning(pop)
#endif

template <class T, bool T_Align16 = false>
class AllocatorWithCleanup : public AllocatorBase<T>
{
public:
	CRYPTOPP_INHERIT_ALLOCATOR_TYPES

	pointer allocate(size_type n, const void * = NULL)
	{
		CheckSize(n);
		if (n == 0)
			return NULL;

		if (CRYPTOPP_BOOL_ALIGN16_ENABLED && T_Align16 && n*sizeof(T) >= 16)
		{
			byte *p;
		#ifdef CRYPTOPP_MM_MALLOC_AVAILABLE
			while (!(p = (byte *)_mm_malloc(sizeof(T)*n, 16)))
		#elif defined(CRYPTOPP_MEMALIGN_AVAILABLE)
			while (!(p = (byte *)memalign(16, sizeof(T)*n)))
		#elif defined(CRYPTOPP_MALLOC_ALIGNMENT_IS_16)
			while (!(p = (byte *)malloc(sizeof(T)*n)))
		#else
			while (!(p = (byte *)malloc(sizeof(T)*n + 16)))
		#endif
				CallNewHandler();

		#ifdef CRYPTOPP_NO_ALIGNED_ALLOC
			size_t adjustment = 16-((size_t)p%16);
			p += adjustment;
			p[-1] = (byte)adjustment;
		#endif

			assert(IsAlignedOn(p, 16));
			return (pointer)p;
		}

		pointer p;
		while (!(p = (pointer)malloc(sizeof(T)*n)))
			CallNewHandler();
		return p;
	}

	void deallocate(void *p, size_type n)
	{
		memset_z(p, 0, n*sizeof(T));

		if (CRYPTOPP_BOOL_ALIGN16_ENABLED && T_Align16 && n*sizeof(T) >= 16)
		{
		#ifdef CRYPTOPP_MM_MALLOC_AVAILABLE
			_mm_free(p);
		#elif defined(CRYPTOPP_NO_ALIGNED_ALLOC)
			p = (byte *)p - ((byte *)p)[-1];
			free(p);
		#else
			free(p);
		#endif
			return;
		}

		free(p);
	}

	pointer reallocate(T *p, size_type oldSize, size_type newSize, bool preserve)
	{
		return StandardReallocate(*this, p, oldSize, newSize, preserve);
	}

	// VS.NET STL enforces the policy of "All STL-compliant allocators have to provide a
	// template class member called rebind".
    template <class U> struct rebind { typedef AllocatorWithCleanup<U, T_Align16> other; };
#if _MSC_VER >= 1500
	AllocatorWithCleanup() {}
	template <class U, bool A> AllocatorWithCleanup(const AllocatorWithCleanup<U, A> &) {}
#endif
};

CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<byte>;
CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word16>;
CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word32>;
CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word64>;
#if CRYPTOPP_BOOL_X86
CRYPTOPP_DLL_TEMPLATE_CLASS AllocatorWithCleanup<word, true>;	// for Integer
#endif

template <class T>
class NullAllocator : public AllocatorBase<T>
{
public:
	CRYPTOPP_INHERIT_ALLOCATOR_TYPES

	pointer allocate(size_type n, const void * = NULL)
	{
		assert(false);
		return NULL;
	}

	void deallocate(void *p, size_type n)
	{
		assert(false);
	}

	size_type max_size() const {return 0;}
};

// This allocator can't be used with standard collections because
// they require that all objects of the same allocator type are equivalent.
// So this is for use with SecBlock only.
template <class T, size_t S, class A = NullAllocator<T>, bool T_Align16 = false>
class FixedSizeAllocatorWithCleanup : public AllocatorBase<T>
{
public:
	CRYPTOPP_INHERIT_ALLOCATOR_TYPES

	FixedSizeAllocatorWithCleanup() : m_allocated(false) {}

	pointer allocate(size_type n)
	{
		assert(IsAlignedOn(m_array, 8));

		if (n <= S && !m_allocated)
		{
			m_allocated = true;
			return GetAlignedArray();
		}
		else
			return m_fallbackAllocator.allocate(n);
	}

	pointer allocate(size_type n, const void *hint)
	{
		if (n <= S && !m_allocated)
		{
			m_allocated = true;
			return GetAlignedArray();
		}
		else
			return m_fallbackAllocator.allocate(n, hint);
	}

	void deallocate(void *p, size_type n)
	{
		if (p == GetAlignedArray())
		{
			assert(n <= S);
			assert(m_allocated);
			m_allocated = false;
			memset(p, 0, n*sizeof(T));
		}
		else
			m_fallbackAllocator.deallocate(p, n);
	}

	pointer reallocate(pointer p, size_type oldSize, size_type newSize, bool preserve)
	{
		if (p == GetAlignedArray() && newSize <= S)
		{
			assert(oldSize <= S);
			if (oldSize > newSize)
				memset(p + newSize, 0, (oldSize-newSize)*sizeof(T));
			return p;
		}

		pointer newPointer = allocate(newSize, NULL);
		if (preserve)
			memcpy(newPointer, p, sizeof(T)*STDMIN(oldSize, newSize));
		deallocate(p, oldSize);
		return newPointer;
	}

	size_type max_size() const {return STDMAX(m_fallbackAllocator.max_size(), S);}

private:
#ifdef __BORLANDC__
	T* GetAlignedArray() {return m_array;}
	T m_array[S];
#else
	T* GetAlignedArray() {return (CRYPTOPP_BOOL_ALIGN16_ENABLED && T_Align16) ? (T*)(((byte *)m_array) + (0-(size_t)m_array)%16) : m_array;}
	CRYPTOPP_ALIGN_DATA(8) T m_array[(CRYPTOPP_BOOL_ALIGN16_ENABLED && T_Align16) ? S+8/sizeof(T) : S];
#endif
	A m_fallbackAllocator;
	bool m_allocated;
};

//! a block of memory allocated using A
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;

	explicit SecBlock(size_type size=0)
		: m_size(size) {m_ptr = m_alloc.allocate(size, NULL);}
	SecBlock(const SecBlock<T, A> &t)
		: m_size(t.m_size) {m_ptr = m_alloc.allocate(m_size, NULL); memcpy_s(m_ptr, m_size*sizeof(T), t.m_ptr, m_size*sizeof(T));}
	SecBlock(const T *t, size_type len)
		: m_size(len)
	{
		m_ptr = m_alloc.allocate(len, NULL);
		if (t == NULL)
			memset_z(m_ptr, 0, len*sizeof(T));
		else
			memcpy(m_ptr, t, len*sizeof(T));
	}

	~SecBlock()
		{m_alloc.deallocate(m_ptr, m_size);}

#ifdef __BORLANDC__
	operator T *() const
		{return (T*)m_ptr;}
#else
	operator const void *() const
		{return m_ptr;}
	operator void *()
		{return m_ptr;}

	operator const T *() const
		{return m_ptr;}
	operator T *()
		{return m_ptr;}
#endif

//	T *operator +(size_type offset)
//		{return m_ptr+offset;}

//	const T *operator +(size_type offset) const
//		{return m_ptr+offset;}

//	T& operator[](size_type index)
//		{assert(index >= 0 && index < m_size); return m_ptr[index];}

//	const T& operator[](size_type index) const
//		{assert(index >= 0 && index < m_size); return m_ptr[index];}

	iterator begin()
		{return m_ptr;}
	const_iterator begin() const
		{return m_ptr;}
	iterator end()
		{return m_ptr+m_size;}
	const_iterator end() const
		{return m_ptr+m_size;}

	typename A::pointer data() {return m_ptr;}
	typename A::const_pointer data() const {return m_ptr;}

	size_type size() const {return m_size;}
	bool empty() const {return m_size == 0;}

	byte * BytePtr() {return (byte *)m_ptr;}
	const byte * BytePtr() const {return (const byte *)m_ptr;}
	size_type SizeInBytes() const {return m_size*sizeof(T);}

	//! set contents and size
	void Assign(const T *t, size_type len)
	{
		New(len);
		memcpy_s(m_ptr, m_size*sizeof(T), t, len*sizeof(T));
	}

	//! copy contents and size from another SecBlock
	void Assign(const SecBlock<T, A> &t)
	{
		New(t.m_size);
		memcpy_s(m_ptr, m_size*sizeof(T), t.m_ptr, m_size*sizeof(T));
	}

	SecBlock<T, A>& operator=(const SecBlock<T, A> &t)
	{
		Assign(t);
		return *this;
	}

	// append to this object
	SecBlock<T, A>& operator+=(const SecBlock<T, A> &t)
	{
		size_type oldSize = m_size;
		Grow(m_size+t.m_size);
		memcpy_s(m_ptr+oldSize, m_size*sizeof(T), t.m_ptr, t.m_size*sizeof(T));
		return *this;
	}

	// append operator
	SecBlock<T, A> operator+(const SecBlock<T, A> &t)
	{
		SecBlock<T, A> result(m_size+t.m_size);
		memcpy_s(result.m_ptr, result.m_size*sizeof(T), m_ptr, m_size*sizeof(T));
		memcpy_s(result.m_ptr+m_size, t.m_size*sizeof(T), t.m_ptr, t.m_size*sizeof(T));
		return result;
	}

	bool operator==(const SecBlock<T, A> &t) const
	{
		return m_size == t.m_size && VerifyBufsEqual(m_ptr, t.m_ptr, m_size*sizeof(T));
	}

	bool operator!=(const SecBlock<T, A> &t) const
	{
		return !operator==(t);
	}

	//! change size, without preserving contents
	void New(size_type newSize)
	{
		m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, false);
		m_size = newSize;
	}

	//! change size and set contents to 0
	void CleanNew(size_type newSize)
	{
		New(newSize);
		memset_z(m_ptr, 0, m_size*sizeof(T));
	}

	//! change size only if newSize > current size. contents are preserved
	void Grow(size_type newSize)
	{
		if (newSize > m_size)
		{
			m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
			m_size = newSize;
		}
	}

	//! change size only if newSize > current size. contents are preserved and additional area is set to 0
	void CleanGrow(size_type newSize)
	{
		if (newSize > m_size)
		{
			m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
			memset(m_ptr+m_size, 0, (newSize-m_size)*sizeof(T));
			m_size = newSize;
		}
	}

	//! change size and preserve contents
	void resize(size_type newSize)
	{
		m_ptr = m_alloc.reallocate(m_ptr, m_size, newSize, true);
		m_size = newSize;
	}

	//! swap contents and size with another SecBlock
	void swap(SecBlock<T, A> &b)
	{
		std::swap(m_alloc, b.m_alloc);
		std::swap(m_size, b.m_size);
		std::swap(m_ptr, b.m_ptr);
	}

//private:
	A m_alloc;
	size_type m_size;
	T *m_ptr;
};

typedef SecBlock<byte> SecByteBlock;
typedef SecBlock<byte, AllocatorWithCleanup<byte, true> > AlignedSecByteBlock;
typedef SecBlock<word> SecWordBlock;

//! a SecBlock with fixed size, allocated statically
template <class T, unsigned int S, class A = FixedSizeAllocatorWithCleanup<T, S> >
class FixedSizeSecBlock : public SecBlock<T, A>
{
public:
	explicit FixedSizeSecBlock() : SecBlock<T, A>(S) {}
};

template <class T, unsigned int S, bool T_Align16 = true>
class FixedSizeAlignedSecBlock : public FixedSizeSecBlock<T, S, FixedSizeAllocatorWithCleanup<T, S, NullAllocator<T>, T_Align16> >
{
};

//! a SecBlock that preallocates size S statically, and uses the heap when this size is exceeded
template <class T, unsigned int S, class A = FixedSizeAllocatorWithCleanup<T, S, AllocatorWithCleanup<T> > >
class SecBlockWithHint : public SecBlock<T, A>
{
public:
	explicit SecBlockWithHint(size_t size) : SecBlock<T, A>(size) {}
};

template<class T, bool A, class U, bool B>
inline bool operator==(const CryptoPP::AllocatorWithCleanup<T, A>&, const CryptoPP::AllocatorWithCleanup<U, B>&) {return (true);}
template<class T, bool A, class U, bool B>
inline bool operator!=(const CryptoPP::AllocatorWithCleanup<T, A>&, const CryptoPP::AllocatorWithCleanup<U, B>&) {return (false);}

NAMESPACE_END

NAMESPACE_BEGIN(std)
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

#endif