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diff --git a/CryptoPP/strciphr.h b/CryptoPP/strciphr.h
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+/*! \file
+ 	This file contains helper classes for implementing stream ciphers.
+
+	All this infrastructure may look very complex compared to what's in Crypto++ 4.x,
+	but stream ciphers implementations now support a lot of new functionality,
+	including better performance (minimizing copying), resetting of keys and IVs, and methods to
+	query which features are supported by a cipher.
+
+	Here's an explanation of these classes. The word "policy" is used here to mean a class with a
+	set of methods that must be implemented by individual stream cipher implementations.
+	This is usually much simpler than the full stream cipher API, which is implemented by
+	either AdditiveCipherTemplate or CFB_CipherTemplate using the policy. So for example, an
+	implementation of SEAL only needs to implement the AdditiveCipherAbstractPolicy interface
+	(since it's an additive cipher, i.e., it xors a keystream into the plaintext).
+	See this line in seal.h:
+
+	typedef SymmetricCipherFinal\<ConcretePolicyHolder\<SEAL_Policy\<B\>, AdditiveCipherTemplate\<\> \> \> Encryption;
+
+	AdditiveCipherTemplate and CFB_CipherTemplate are designed so that they don't need
+	to take a policy class as a template parameter (although this is allowed), so that
+	their code is not duplicated for each new cipher. Instead they each
+	get a reference to an abstract policy interface by calling AccessPolicy() on itself, so
+	AccessPolicy() must be overriden to return the actual policy reference. This is done
+	by the ConceretePolicyHolder class. Finally, SymmetricCipherFinal implements the constructors and
+	other functions that must be implemented by the most derived class.
+*/
+
+#ifndef CRYPTOPP_STRCIPHR_H
+#define CRYPTOPP_STRCIPHR_H
+
+#include "seckey.h"
+#include "secblock.h"
+#include "argnames.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+template <class POLICY_INTERFACE, class BASE = Empty>
+class CRYPTOPP_NO_VTABLE AbstractPolicyHolder : public BASE
+{
+public:
+	typedef POLICY_INTERFACE PolicyInterface;
+	virtual ~AbstractPolicyHolder() {}
+
+protected:
+	virtual const POLICY_INTERFACE & GetPolicy() const =0;
+	virtual POLICY_INTERFACE & AccessPolicy() =0;
+};
+
+template <class POLICY, class BASE, class POLICY_INTERFACE = CPP_TYPENAME BASE::PolicyInterface>
+class ConcretePolicyHolder : public BASE, protected POLICY
+{
+protected:
+	const POLICY_INTERFACE & GetPolicy() const {return *this;}
+	POLICY_INTERFACE & AccessPolicy() {return *this;}
+};
+
+enum KeystreamOperationFlags {OUTPUT_ALIGNED=1, INPUT_ALIGNED=2, INPUT_NULL = 4};
+enum KeystreamOperation {
+	WRITE_KEYSTREAM				= INPUT_NULL, 
+	WRITE_KEYSTREAM_ALIGNED		= INPUT_NULL | OUTPUT_ALIGNED, 
+	XOR_KEYSTREAM				= 0, 
+	XOR_KEYSTREAM_INPUT_ALIGNED = INPUT_ALIGNED, 
+	XOR_KEYSTREAM_OUTPUT_ALIGNED= OUTPUT_ALIGNED, 
+	XOR_KEYSTREAM_BOTH_ALIGNED	= OUTPUT_ALIGNED | INPUT_ALIGNED};
+
+struct CRYPTOPP_DLL CRYPTOPP_NO_VTABLE AdditiveCipherAbstractPolicy
+{
+	virtual ~AdditiveCipherAbstractPolicy() {}
+	virtual unsigned int GetAlignment() const {return 1;}
+	virtual unsigned int GetBytesPerIteration() const =0;
+	virtual unsigned int GetOptimalBlockSize() const {return GetBytesPerIteration();}
+	virtual unsigned int GetIterationsToBuffer() const =0;
+	virtual void WriteKeystream(byte *keystream, size_t iterationCount)
+		{OperateKeystream(KeystreamOperation(INPUT_NULL | (KeystreamOperationFlags)IsAlignedOn(keystream, GetAlignment())), keystream, NULL, iterationCount);}
+	virtual bool CanOperateKeystream() const {return false;}
+	virtual void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount) {assert(false);}
+	virtual void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length) =0;
+	virtual void CipherResynchronize(byte *keystreamBuffer, const byte *iv, size_t length) {throw NotImplemented("SimpleKeyingInterface: this object doesn't support resynchronization");}
+	virtual bool CipherIsRandomAccess() const =0;
+	virtual void SeekToIteration(lword iterationCount) {assert(!CipherIsRandomAccess()); throw NotImplemented("StreamTransformation: this object doesn't support random access");}
+};
+
+template <typename WT, unsigned int W, unsigned int X = 1, class BASE = AdditiveCipherAbstractPolicy>
+struct CRYPTOPP_NO_VTABLE AdditiveCipherConcretePolicy : public BASE
+{
+	typedef WT WordType;
+	CRYPTOPP_CONSTANT(BYTES_PER_ITERATION = sizeof(WordType) * W)
+
+#if !(CRYPTOPP_BOOL_X86 || CRYPTOPP_BOOL_X64)
+	unsigned int GetAlignment() const {return GetAlignmentOf<WordType>();}
+#endif
+	unsigned int GetBytesPerIteration() const {return BYTES_PER_ITERATION;}
+	unsigned int GetIterationsToBuffer() const {return X;}
+	bool CanOperateKeystream() const {return true;}
+	virtual void OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount) =0;
+};
+
+// use these to implement OperateKeystream
+#define CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, b, i, a)	\
+	PutWord(bool(x & OUTPUT_ALIGNED), b, output+i*sizeof(WordType), (x & INPUT_NULL) ? a : a ^ GetWord<WordType>(bool(x & INPUT_ALIGNED), b, input+i*sizeof(WordType)));
+#define CRYPTOPP_KEYSTREAM_OUTPUT_XMM(x, i, a)	{\
+	__m128i t = (x & INPUT_NULL) ? a : _mm_xor_si128(a, (x & INPUT_ALIGNED) ? _mm_load_si128((__m128i *)input+i) : _mm_loadu_si128((__m128i *)input+i));\
+	if (x & OUTPUT_ALIGNED) _mm_store_si128((__m128i *)output+i, t);\
+	else _mm_storeu_si128((__m128i *)output+i, t);}
+#define CRYPTOPP_KEYSTREAM_OUTPUT_SWITCH(x, y)	\
+	switch (operation)							\
+	{											\
+		case WRITE_KEYSTREAM:					\
+			x(WRITE_KEYSTREAM)					\
+			break;								\
+		case XOR_KEYSTREAM:						\
+			x(XOR_KEYSTREAM)					\
+			input += y;							\
+			break;								\
+		case XOR_KEYSTREAM_INPUT_ALIGNED:		\
+			x(XOR_KEYSTREAM_INPUT_ALIGNED)		\
+			input += y;							\
+			break;								\
+		case XOR_KEYSTREAM_OUTPUT_ALIGNED:		\
+			x(XOR_KEYSTREAM_OUTPUT_ALIGNED)		\
+			input += y;							\
+			break;								\
+		case WRITE_KEYSTREAM_ALIGNED:			\
+			x(WRITE_KEYSTREAM_ALIGNED)			\
+			break;								\
+		case XOR_KEYSTREAM_BOTH_ALIGNED:		\
+			x(XOR_KEYSTREAM_BOTH_ALIGNED)		\
+			input += y;							\
+			break;								\
+	}											\
+	output += y;
+
+template <class BASE = AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher> >
+class CRYPTOPP_NO_VTABLE AdditiveCipherTemplate : public BASE, public RandomNumberGenerator
+{
+public:
+	void GenerateBlock(byte *output, size_t size);
+    void ProcessData(byte *outString, const byte *inString, size_t length);
+	void Resynchronize(const byte *iv, int length=-1);
+	unsigned int OptimalBlockSize() const {return this->GetPolicy().GetOptimalBlockSize();}
+	unsigned int GetOptimalNextBlockSize() const {return (unsigned int)this->m_leftOver;}
+	unsigned int OptimalDataAlignment() const {return this->GetPolicy().GetAlignment();}
+	bool IsSelfInverting() const {return true;}
+	bool IsForwardTransformation() const {return true;}
+	bool IsRandomAccess() const {return this->GetPolicy().CipherIsRandomAccess();}
+	void Seek(lword position);
+
+	typedef typename BASE::PolicyInterface PolicyInterface;
+
+protected:
+	void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
+
+	unsigned int GetBufferByteSize(const PolicyInterface &policy) const {return policy.GetBytesPerIteration() * policy.GetIterationsToBuffer();}
+
+	inline byte * KeystreamBufferBegin() {return this->m_buffer.data();}
+	inline byte * KeystreamBufferEnd() {return (this->m_buffer.data() + this->m_buffer.size());}
+
+	SecByteBlock m_buffer;
+	size_t m_leftOver;
+};
+
+class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE CFB_CipherAbstractPolicy
+{
+public:
+	virtual ~CFB_CipherAbstractPolicy() {}
+	virtual unsigned int GetAlignment() const =0;
+	virtual unsigned int GetBytesPerIteration() const =0;
+	virtual byte * GetRegisterBegin() =0;
+	virtual void TransformRegister() =0;
+	virtual bool CanIterate() const {return false;}
+	virtual void Iterate(byte *output, const byte *input, CipherDir dir, size_t iterationCount) {assert(false); throw 0;}
+	virtual void CipherSetKey(const NameValuePairs &params, const byte *key, size_t length) =0;
+	virtual void CipherResynchronize(const byte *iv, size_t length) {throw NotImplemented("SimpleKeyingInterface: this object doesn't support resynchronization");}
+};
+
+template <typename WT, unsigned int W, class BASE = CFB_CipherAbstractPolicy>
+struct CRYPTOPP_NO_VTABLE CFB_CipherConcretePolicy : public BASE
+{
+	typedef WT WordType;
+
+	unsigned int GetAlignment() const {return sizeof(WordType);}
+	unsigned int GetBytesPerIteration() const {return sizeof(WordType) * W;}
+	bool CanIterate() const {return true;}
+	void TransformRegister() {this->Iterate(NULL, NULL, ENCRYPTION, 1);}
+
+	template <class B>
+	struct RegisterOutput
+	{
+		RegisterOutput(byte *output, const byte *input, CipherDir dir)
+			: m_output(output), m_input(input), m_dir(dir) {}
+
+		inline RegisterOutput& operator()(WordType &registerWord)
+		{
+			assert(IsAligned<WordType>(m_output));
+			assert(IsAligned<WordType>(m_input));
+
+			if (!NativeByteOrderIs(B::ToEnum()))
+				registerWord = ByteReverse(registerWord);
+
+			if (m_dir == ENCRYPTION)
+			{
+				if (m_input == NULL)
+					assert(m_output == NULL);
+				else
+				{
+					WordType ct = *(const WordType *)m_input ^ registerWord;
+					registerWord = ct;
+					*(WordType*)m_output = ct;
+					m_input += sizeof(WordType);
+					m_output += sizeof(WordType);
+				}
+			}
+			else
+			{
+				WordType ct = *(const WordType *)m_input;
+				*(WordType*)m_output = registerWord ^ ct;
+				registerWord = ct;
+				m_input += sizeof(WordType);
+				m_output += sizeof(WordType);
+			}
+
+			// registerWord is left unreversed so it can be xor-ed with further input
+
+			return *this;
+		}
+
+		byte *m_output;
+		const byte *m_input;
+		CipherDir m_dir;
+	};
+};
+
+template <class BASE>
+class CRYPTOPP_NO_VTABLE CFB_CipherTemplate : public BASE
+{
+public:
+	void ProcessData(byte *outString, const byte *inString, size_t length);
+	void Resynchronize(const byte *iv, int length=-1);
+	unsigned int OptimalBlockSize() const {return this->GetPolicy().GetBytesPerIteration();}
+	unsigned int GetOptimalNextBlockSize() const {return (unsigned int)m_leftOver;}
+	unsigned int OptimalDataAlignment() const {return this->GetPolicy().GetAlignment();}
+	bool IsRandomAccess() const {return false;}
+	bool IsSelfInverting() const {return false;}
+
+	typedef typename BASE::PolicyInterface PolicyInterface;
+
+protected:
+	virtual void CombineMessageAndShiftRegister(byte *output, byte *reg, const byte *message, size_t length) =0;
+
+	void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
+
+	size_t m_leftOver;
+};
+
+template <class BASE = AbstractPolicyHolder<CFB_CipherAbstractPolicy, SymmetricCipher> >
+class CRYPTOPP_NO_VTABLE CFB_EncryptionTemplate : public CFB_CipherTemplate<BASE>
+{
+	bool IsForwardTransformation() const {return true;}
+	void CombineMessageAndShiftRegister(byte *output, byte *reg, const byte *message, size_t length);
+};
+
+template <class BASE = AbstractPolicyHolder<CFB_CipherAbstractPolicy, SymmetricCipher> >
+class CRYPTOPP_NO_VTABLE CFB_DecryptionTemplate : public CFB_CipherTemplate<BASE>
+{
+	bool IsForwardTransformation() const {return false;}
+	void CombineMessageAndShiftRegister(byte *output, byte *reg, const byte *message, size_t length);
+};
+
+template <class BASE>
+class CFB_RequireFullDataBlocks : public BASE
+{
+public:
+	unsigned int MandatoryBlockSize() const {return this->OptimalBlockSize();}
+};
+
+//! _
+template <class BASE, class INFO = BASE>
+class SymmetricCipherFinal : public AlgorithmImpl<SimpleKeyingInterfaceImpl<BASE, INFO>, INFO>
+{
+public:
+ 	SymmetricCipherFinal() {}
+	SymmetricCipherFinal(const byte *key)
+		{this->SetKey(key, this->DEFAULT_KEYLENGTH);}
+	SymmetricCipherFinal(const byte *key, size_t length)
+		{this->SetKey(key, length);}
+	SymmetricCipherFinal(const byte *key, size_t length, const byte *iv)
+		{this->SetKeyWithIV(key, length, iv);}
+
+	Clonable * Clone() const {return static_cast<SymmetricCipher *>(new SymmetricCipherFinal<BASE, INFO>(*this));}
+};
+
+NAMESPACE_END
+
+#ifdef CRYPTOPP_MANUALLY_INSTANTIATE_TEMPLATES
+#include "strciphr.cpp"
+#endif
+
+NAMESPACE_BEGIN(CryptoPP)
+CRYPTOPP_DLL_TEMPLATE_CLASS AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher>;
+CRYPTOPP_DLL_TEMPLATE_CLASS AdditiveCipherTemplate<AbstractPolicyHolder<AdditiveCipherAbstractPolicy, SymmetricCipher> >;
+CRYPTOPP_DLL_TEMPLATE_CLASS CFB_CipherTemplate<AbstractPolicyHolder<CFB_CipherAbstractPolicy, SymmetricCipher> >;
+CRYPTOPP_DLL_TEMPLATE_CLASS CFB_EncryptionTemplate<AbstractPolicyHolder<CFB_CipherAbstractPolicy, SymmetricCipher> >;
+CRYPTOPP_DLL_TEMPLATE_CLASS CFB_DecryptionTemplate<AbstractPolicyHolder<CFB_CipherAbstractPolicy, SymmetricCipher> >;
+NAMESPACE_END
+
+#endif