misc.h

#ifndef CRYPTOPP_MISC_H
#define CRYPTOPP_MISC_H

#include "cryptlib.h"
#include "smartptr.h"
#include <string.h>             // for memcpy and memmove

#ifdef _MSC_VER
        #if _MSC_VER >= 1400
                // VC2005 workaround: disable declarations that conflict with winnt.h
                #define _interlockedbittestandset CRYPTOPP_DISABLED_INTRINSIC_1
                #define _interlockedbittestandreset CRYPTOPP_DISABLED_INTRINSIC_2
                #define _interlockedbittestandset64 CRYPTOPP_DISABLED_INTRINSIC_3
                #define _interlockedbittestandreset64 CRYPTOPP_DISABLED_INTRINSIC_4
                #include <intrin.h>
                #undef _interlockedbittestandset
                #undef _interlockedbittestandreset
                #undef _interlockedbittestandset64
                #undef _interlockedbittestandreset64
                #define CRYPTOPP_FAST_ROTATE(x) 1
        #elif _MSC_VER >= 1300
                #define CRYPTOPP_FAST_ROTATE(x) ((x) == 32 | (x) == 64)
        #else
                #define CRYPTOPP_FAST_ROTATE(x) ((x) == 32)
        #endif
#elif (defined(__MWERKS__) && TARGET_CPU_PPC) || \
        (defined(__GNUC__) && (defined(_ARCH_PWR2) || defined(_ARCH_PWR) || defined(_ARCH_PPC) || defined(_ARCH_PPC64) || defined(_ARCH_COM)))
        #define CRYPTOPP_FAST_ROTATE(x) ((x) == 32)
#elif defined(__GNUC__) && (CRYPTOPP_BOOL_X64 || CRYPTOPP_BOOL_X86)     // depend on GCC's peephole optimization to generate rotate instructions
        #define CRYPTOPP_FAST_ROTATE(x) 1
#else
        #define CRYPTOPP_FAST_ROTATE(x) 0
#endif

#ifdef __BORLANDC__
#include <mem.h>
#endif

#if defined(__GNUC__) && defined(__linux__)
#define CRYPTOPP_BYTESWAP_AVAILABLE
#include <byteswap.h>
#endif

NAMESPACE_BEGIN(CryptoPP)

// ************** compile-time assertion ***************

template <bool b>
struct CompileAssert
{
        static char dummy[2*b-1];
};

#define CRYPTOPP_COMPILE_ASSERT(assertion) CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, __LINE__)
#if defined(CRYPTOPP_EXPORTS) || defined(CRYPTOPP_IMPORTS)
#define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance)
#else
#define CRYPTOPP_COMPILE_ASSERT_INSTANCE(assertion, instance) static CompileAssert<(assertion)> CRYPTOPP_ASSERT_JOIN(cryptopp_assert_, instance)
#endif
#define CRYPTOPP_ASSERT_JOIN(X, Y) CRYPTOPP_DO_ASSERT_JOIN(X, Y)
#define CRYPTOPP_DO_ASSERT_JOIN(X, Y) X##Y

// ************** misc classes ***************

class CRYPTOPP_DLL Empty
{
};

//! _
template <class BASE1, class BASE2>
class CRYPTOPP_NO_VTABLE TwoBases : public BASE1, public BASE2
{
};

//! _
template <class BASE1, class BASE2, class BASE3>
class CRYPTOPP_NO_VTABLE ThreeBases : public BASE1, public BASE2, public BASE3
{
};

template <class T>
class ObjectHolder
{
protected:
        T m_object;
};

class NotCopyable
{
public:
        NotCopyable() {}
private:
    NotCopyable(const NotCopyable &);
    void operator=(const NotCopyable &);
};

template <class T>
struct NewObject
{
        T* operator()() const {return new T;}
};

/*! This function safely initializes a static object in a multithreaded environment without using locks (for portability).
        Note that if two threads call Ref() at the same time, they may get back different references, and one object 
        may end up being memory leaked. This is by design.
*/
template <class T, class F = NewObject<T>, int instance=0>
class Singleton
{
public:
        Singleton(F objectFactory = F()) : m_objectFactory(objectFactory) {}

        // prevent this function from being inlined
        CRYPTOPP_NOINLINE const T & Ref(CRYPTOPP_NOINLINE_DOTDOTDOT) const;

private:
        F m_objectFactory;
};

template <class T, class F, int instance>
const T & Singleton<T, F, instance>::Ref(CRYPTOPP_NOINLINE_DOTDOTDOT) const
{
        static volatile simple_ptr<T> s_pObject;
        T *p = s_pObject.m_p;

        if (p)
                return *p;

        T *newObject = m_objectFactory();
        p = s_pObject.m_p;

        if (p)
        {
                delete newObject;
                return *p;
        }

        s_pObject.m_p = newObject;
        return *newObject;
}

// ************** misc functions ***************

#if (!__STDC_WANT_SECURE_LIB__)
inline void memcpy_s(void *dest, size_t sizeInBytes, const void *src, size_t count)
{
        if (count > sizeInBytes)
                throw InvalidArgument("memcpy_s: buffer overflow");
        memcpy(dest, src, count);
}

inline void memmove_s(void *dest, size_t sizeInBytes, const void *src, size_t count)
{
        if (count > sizeInBytes)
                throw InvalidArgument("memmove_s: buffer overflow");
        memmove(dest, src, count);
}

#if __BORLANDC__ >= 0x620
// C++Builder 2010 workaround: can't use std::memcpy_s because it doesn't allow 0 lengths
#define memcpy_s CryptoPP::memcpy_s
#define memmove_s CryptoPP::memmove_s
#endif
#endif

inline void * memset_z(void *ptr, int value, size_t num)
{
// avoid extranous warning on GCC 4.3.2 Ubuntu 8.10
#if CRYPTOPP_GCC_VERSION >= 30001
        if (__builtin_constant_p(num) && num==0)
                return ptr;
#endif
        return memset(ptr, value, num);
}

// can't use std::min or std::max in MSVC60 or Cygwin 1.1.0
template <class T> inline const T& STDMIN(const T& a, const T& b)
{
        return b < a ? b : a;
}

template <class T1, class T2> inline const T1 UnsignedMin(const T1& a, const T2& b)
{
        CRYPTOPP_COMPILE_ASSERT((sizeof(T1)<=sizeof(T2) && T2(-1)>0) || (sizeof(T1)>sizeof(T2) && T1(-1)>0));
        assert(a==0 || a>0);    // GCC workaround: get rid of the warning "comparison is always true due to limited range of data type"
        assert(b>=0);

        if (sizeof(T1)<=sizeof(T2))
                return b < (T2)a ? (T1)b : a;
        else
                return (T1)b < a ? (T1)b : a;
}

template <class T> inline const T& STDMAX(const T& a, const T& b)
{
        return a < b ? b : a;
}

#define RETURN_IF_NONZERO(x) size_t returnedValue = x; if (returnedValue) return returnedValue

// this version of the macro is fastest on Pentium 3 and Pentium 4 with MSVC 6 SP5 w/ Processor Pack
#define GETBYTE(x, y) (unsigned int)byte((x)>>(8*(y)))
// these may be faster on other CPUs/compilers
// #define GETBYTE(x, y) (unsigned int)(((x)>>(8*(y)))&255)
// #define GETBYTE(x, y) (((byte *)&(x))[y])

#define CRYPTOPP_GET_BYTE_AS_BYTE(x, y) byte((x)>>(8*(y)))

template <class T>
unsigned int Parity(T value)
{
        for (unsigned int i=8*sizeof(value)/2; i>0; i/=2)
                value ^= value >> i;
        return (unsigned int)value&1;
}

template <class T>
unsigned int BytePrecision(const T &value)
{
        if (!value)
                return 0;

        unsigned int l=0, h=8*sizeof(value);

        while (h-l > 8)
        {
                unsigned int t = (l+h)/2;
                if (value >> t)
                        l = t;
                else
                        h = t;
        }

        return h/8;
}

template <class T>
unsigned int BitPrecision(const T &value)
{
        if (!value)
                return 0;

        unsigned int l=0, h=8*sizeof(value);

        while (h-l > 1)
        {
                unsigned int t = (l+h)/2;
                if (value >> t)
                        l = t;
                else
                        h = t;
        }

        return h;
}

inline unsigned int TrailingZeros(word32 v)
{
#if defined(__GNUC__) && CRYPTOPP_GCC_VERSION >= 30400
        return __builtin_ctz(v);
#elif defined(_MSC_VER) && _MSC_VER >= 1400
        unsigned long result;
        _BitScanForward(&result, v);
        return result;
#else
        // from http://graphics.stanford.edu/~seander/bithacks.html#ZerosOnRightMultLookup
        static const int MultiplyDeBruijnBitPosition[32] = 
        {
          0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8, 
          31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9
        };
        return MultiplyDeBruijnBitPosition[((word32)((v & -v) * 0x077CB531U)) >> 27];
#endif
}

inline unsigned int TrailingZeros(word64 v)
{
#if defined(__GNUC__) && CRYPTOPP_GCC_VERSION >= 30400
        return __builtin_ctzll(v);
#elif defined(_MSC_VER) && _MSC_VER >= 1400 && (defined(_M_X64) || defined(_M_IA64))
        unsigned long result;
        _BitScanForward64(&result, v);
        return result;
#else
        return word32(v) ? TrailingZeros(word32(v)) : 32 + TrailingZeros(word32(v>>32));
#endif
}

template <class T>
inline T Crop(T value, size_t size)
{
        if (size < 8*sizeof(value))
        return T(value & ((T(1) << size) - 1));
        else
                return value;
}

template <class T1, class T2>
inline bool SafeConvert(T1 from, T2 &to)
{
        to = (T2)from;
        if (from != to || (from > 0) != (to > 0))
                return false;
        return true;
}

inline size_t BitsToBytes(size_t bitCount)
{
        return ((bitCount+7)/(8));
}

inline size_t BytesToWords(size_t byteCount)
{
        return ((byteCount+WORD_SIZE-1)/WORD_SIZE);
}

inline size_t BitsToWords(size_t bitCount)
{
        return ((bitCount+WORD_BITS-1)/(WORD_BITS));
}

inline size_t BitsToDwords(size_t bitCount)
{
        return ((bitCount+2*WORD_BITS-1)/(2*WORD_BITS));
}

CRYPTOPP_DLL void CRYPTOPP_API xorbuf(byte *buf, const byte *mask, size_t count);
CRYPTOPP_DLL void CRYPTOPP_API xorbuf(byte *output, const byte *input, const byte *mask, size_t count);

CRYPTOPP_DLL bool CRYPTOPP_API VerifyBufsEqual(const byte *buf1, const byte *buf2, size_t count);

template <class T>
inline bool IsPowerOf2(const T &n)
{
        return n > 0 && (n & (n-1)) == 0;
}

template <class T1, class T2>
inline T2 ModPowerOf2(const T1 &a, const T2 &b)
{
        assert(IsPowerOf2(b));
        return T2(a) & (b-1);
}

template <class T1, class T2>
inline T1 RoundDownToMultipleOf(const T1 &n, const T2 &m)
{
        if (IsPowerOf2(m))
                return n - ModPowerOf2(n, m);
        else
                return n - n%m;
}

template <class T1, class T2>
inline T1 RoundUpToMultipleOf(const T1 &n, const T2 &m)
{
        if (n+m-1 < n)
                throw InvalidArgument("RoundUpToMultipleOf: integer overflow");
        return RoundDownToMultipleOf(n+m-1, m);
}

template <class T>
inline unsigned int GetAlignmentOf(T *dummy=NULL)       // VC60 workaround
{
#ifdef CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS
        if (sizeof(T) < 16)
                return 1;
#endif

#if (_MSC_VER >= 1300)
        return __alignof(T);
#elif defined(__GNUC__)
        return __alignof__(T);
#elif CRYPTOPP_BOOL_SLOW_WORD64
        return UnsignedMin(4U, sizeof(T));
#else
        return sizeof(T);
#endif
}

inline bool IsAlignedOn(const void *p, unsigned int alignment)
{
        return alignment==1 || (IsPowerOf2(alignment) ? ModPowerOf2((size_t)p, alignment) == 0 : (size_t)p % alignment == 0);
}

template <class T>
inline bool IsAligned(const void *p, T *dummy=NULL)     // VC60 workaround
{
        return IsAlignedOn(p, GetAlignmentOf<T>());
}

#ifdef IS_LITTLE_ENDIAN
        typedef LittleEndian NativeByteOrder;
#else
        typedef BigEndian NativeByteOrder;
#endif

inline ByteOrder GetNativeByteOrder()
{
        return NativeByteOrder::ToEnum();
}

inline bool NativeByteOrderIs(ByteOrder order)
{
        return order == GetNativeByteOrder();
}

template <class T>
std::string IntToString(T a, unsigned int base = 10)
{
        if (a == 0)
                return "0";
        bool negate = false;
        if (a < 0)
        {
                negate = true;
                a = 0-a;        // VC .NET does not like -a
        }
        std::string result;
        while (a > 0)
        {
                T digit = a % base;
                result = char((digit < 10 ? '0' : ('a' - 10)) + digit) + result;
                a /= base;
        }
        if (negate)
                result = "-" + result;
        return result;
}

template <class T1, class T2>
inline T1 SaturatingSubtract(const T1 &a, const T2 &b)
{
        return T1((a > b) ? (a - b) : 0);
}

template <class T>
inline CipherDir GetCipherDir(const T &obj)
{
        return obj.IsForwardTransformation() ? ENCRYPTION : DECRYPTION;
}

CRYPTOPP_DLL void CRYPTOPP_API CallNewHandler();

inline void IncrementCounterByOne(byte *inout, unsigned int s)
{
        for (int i=s-1, carry=1; i>=0 && carry; i--)
                carry = !++inout[i];
}

inline void IncrementCounterByOne(byte *output, const byte *input, unsigned int s)
{
        int i, carry;
        for (i=s-1, carry=1; i>=0 && carry; i--)
                carry = ((output[i] = input[i]+1) == 0);
        memcpy_s(output, s, input, i+1);
}

template <class T>
inline void ConditionalSwap(bool c, T &a, T &b)
{
        T t = c * (a ^ b);
        a ^= t;
        b ^= t;
}

template <class T>
inline void ConditionalSwapPointers(bool c, T &a, T &b)
{
        ptrdiff_t t = c * (a - b);
        a -= t;
        b += t;
}

// see http://www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/protect-secrets.html
// and https://www.securecoding.cert.org/confluence/display/cplusplus/MSC06-CPP.+Be+aware+of+compiler+optimization+when+dealing+with+sensitive+data
template <class T>
void SecureWipeBuffer(T *buf, size_t n)
{
        // GCC 4.3.2 on Cygwin optimizes away the first store if this loop is done in the forward direction
        volatile T *p = buf+n;
        while (n--)
                *(--p) = 0;
}

#if (_MSC_VER >= 1400 || defined(__GNUC__)) && (CRYPTOPP_BOOL_X64 || CRYPTOPP_BOOL_X86)

template<> inline void SecureWipeBuffer(byte *buf, size_t n)
{
        volatile byte *p = buf;
#ifdef __GNUC__
        asm volatile("rep stosb" : "+c"(n), "+D"(p) : "a"(0) : "memory");
#else
        __stosb((byte *)(size_t)p, 0, n);
#endif
}

template<> inline void SecureWipeBuffer(word16 *buf, size_t n)
{
        volatile word16 *p = buf;
#ifdef __GNUC__
        asm volatile("rep stosw" : "+c"(n), "+D"(p) : "a"(0) : "memory");
#else
        __stosw((word16 *)(size_t)p, 0, n);
#endif
}

template<> inline void SecureWipeBuffer(word32 *buf, size_t n)
{
        volatile word32 *p = buf;
#ifdef __GNUC__
        asm volatile("rep stosl" : "+c"(n), "+D"(p) : "a"(0) : "memory");
#else
        __stosd((unsigned long *)(size_t)p, 0, n);
#endif
}

template<> inline void SecureWipeBuffer(word64 *buf, size_t n)
{
#if CRYPTOPP_BOOL_X64
        volatile word64 *p = buf;
#ifdef __GNUC__
        asm volatile("rep stosq" : "+c"(n), "+D"(p) : "a"(0) : "memory");
#else
        __stosq((word64 *)(size_t)p, 0, n);
#endif
#else
        SecureWipeBuffer((word32 *)buf, 2*n);
#endif
}

#endif  // #if (_MSC_VER >= 1400 || defined(__GNUC__)) && (CRYPTOPP_BOOL_X64 || CRYPTOPP_BOOL_X86)

template <class T>
inline void SecureWipeArray(T *buf, size_t n)
{
        if (sizeof(T) % 8 == 0 && GetAlignmentOf<T>() % GetAlignmentOf<word64>() == 0)
                SecureWipeBuffer((word64 *)buf, n * (sizeof(T)/8));
        else if (sizeof(T) % 4 == 0 && GetAlignmentOf<T>() % GetAlignmentOf<word32>() == 0)
                SecureWipeBuffer((word32 *)buf, n * (sizeof(T)/4));
        else if (sizeof(T) % 2 == 0 && GetAlignmentOf<T>() % GetAlignmentOf<word16>() == 0)
                SecureWipeBuffer((word16 *)buf, n * (sizeof(T)/2));
        else
                SecureWipeBuffer((byte *)buf, n * sizeof(T));
}

// this function uses wcstombs(), which assumes that setlocale() has been called
static std::string StringNarrow(const wchar_t *str, bool throwOnError = true)
{
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4996)  //  'wcstombs': This function or variable may be unsafe.
#endif
        size_t size = wcstombs(NULL, str, 0);
        if (size == size_t(0)-1)
        {
                if (throwOnError)
                        throw InvalidArgument("StringNarrow: wcstombs() call failed");
                else
                        return std::string();
        }
        std::string result(size, 0);
        wcstombs(&result[0], str, size);
        return result;
#ifdef _MSC_VER
#pragma warning(pop)
#endif
}

#if CRYPTOPP_BOOL_ALIGN16_ENABLED
CRYPTOPP_DLL void * CRYPTOPP_API AlignedAllocate(size_t size);
CRYPTOPP_DLL void CRYPTOPP_API AlignedDeallocate(void *p);
#endif

CRYPTOPP_DLL void * CRYPTOPP_API UnalignedAllocate(size_t size);
CRYPTOPP_DLL void CRYPTOPP_API UnalignedDeallocate(void *p);

// ************** rotate functions ***************

template <class T> inline T rotlFixed(T x, unsigned int y)
{
        assert(y < sizeof(T)*8);
        return T((x<<y) | (x>>(sizeof(T)*8-y)));
}

template <class T> inline T rotrFixed(T x, unsigned int y)
{
        assert(y < sizeof(T)*8);
        return T((x>>y) | (x<<(sizeof(T)*8-y)));
}

template <class T> inline T rotlVariable(T x, unsigned int y)
{
        assert(y < sizeof(T)*8);
        return T((x<<y) | (x>>(sizeof(T)*8-y)));
}

template <class T> inline T rotrVariable(T x, unsigned int y)
{
        assert(y < sizeof(T)*8);
        return T((x>>y) | (x<<(sizeof(T)*8-y)));
}

template <class T> inline T rotlMod(T x, unsigned int y)
{
        y %= sizeof(T)*8;
        return T((x<<y) | (x>>(sizeof(T)*8-y)));
}

template <class T> inline T rotrMod(T x, unsigned int y)
{
        y %= sizeof(T)*8;
        return T((x>>y) | (x<<(sizeof(T)*8-y)));
}

#ifdef _MSC_VER

template<> inline word32 rotlFixed<word32>(word32 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _lrotl(x, y) : x;
}

template<> inline word32 rotrFixed<word32>(word32 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _lrotr(x, y) : x;
}

template<> inline word32 rotlVariable<word32>(word32 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _lrotl(x, y);
}

template<> inline word32 rotrVariable<word32>(word32 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _lrotr(x, y);
}

template<> inline word32 rotlMod<word32>(word32 x, unsigned int y)
{
        return _lrotl(x, y);
}

template<> inline word32 rotrMod<word32>(word32 x, unsigned int y)
{
        return _lrotr(x, y);
}

#endif // #ifdef _MSC_VER

#if _MSC_VER >= 1300 && !defined(__INTEL_COMPILER)
// Intel C++ Compiler 10.0 calls a function instead of using the rotate instruction when using these instructions

template<> inline word64 rotlFixed<word64>(word64 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotl64(x, y) : x;
}

template<> inline word64 rotrFixed<word64>(word64 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotr64(x, y) : x;
}

template<> inline word64 rotlVariable<word64>(word64 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotl64(x, y);
}

template<> inline word64 rotrVariable<word64>(word64 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotr64(x, y);
}

template<> inline word64 rotlMod<word64>(word64 x, unsigned int y)
{
        return _rotl64(x, y);
}

template<> inline word64 rotrMod<word64>(word64 x, unsigned int y)
{
        return _rotr64(x, y);
}

#endif // #if _MSC_VER >= 1310

#if _MSC_VER >= 1400 && !defined(__INTEL_COMPILER)
// Intel C++ Compiler 10.0 gives undefined externals with these

template<> inline word16 rotlFixed<word16>(word16 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotl16(x, y) : x;
}

template<> inline word16 rotrFixed<word16>(word16 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotr16(x, y) : x;
}

template<> inline word16 rotlVariable<word16>(word16 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotl16(x, y);
}

template<> inline word16 rotrVariable<word16>(word16 x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotr16(x, y);
}

template<> inline word16 rotlMod<word16>(word16 x, unsigned int y)
{
        return _rotl16(x, y);
}

template<> inline word16 rotrMod<word16>(word16 x, unsigned int y)
{
        return _rotr16(x, y);
}

template<> inline byte rotlFixed<byte>(byte x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotl8(x, y) : x;
}

template<> inline byte rotrFixed<byte>(byte x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return y ? _rotr8(x, y) : x;
}

template<> inline byte rotlVariable<byte>(byte x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotl8(x, y);
}

template<> inline byte rotrVariable<byte>(byte x, unsigned int y)
{
        assert(y < 8*sizeof(x));
        return _rotr8(x, y);
}

template<> inline byte rotlMod<byte>(byte x, unsigned int y)
{
        return _rotl8(x, y);
}

template<> inline byte rotrMod<byte>(byte x, unsigned int y)
{
        return _rotr8(x, y);
}

#endif // #if _MSC_VER >= 1400

#if (defined(__MWERKS__) && TARGET_CPU_PPC)

template<> inline word32 rotlFixed<word32>(word32 x, unsigned int y)
{
        assert(y < 32);
        return y ? __rlwinm(x,y,0,31) : x;
}

template<> inline word32 rotrFixed<word32>(word32 x, unsigned int y)
{
        assert(y < 32);
        return y ? __rlwinm(x,32-y,0,31) : x;
}

template<> inline word32 rotlVariable<word32>(word32 x, unsigned int y)
{
        assert(y < 32);
        return (__rlwnm(x,y,0,31));
}

template<> inline word32 rotrVariable<word32>(word32 x, unsigned int y)
{
        assert(y < 32);
        return (__rlwnm(x,32-y,0,31));
}

template<> inline word32 rotlMod<word32>(word32 x, unsigned int y)
{
        return (__rlwnm(x,y,0,31));
}

template<> inline word32 rotrMod<word32>(word32 x, unsigned int y)
{
        return (__rlwnm(x,32-y,0,31));
}

#endif // #if (defined(__MWERKS__) && TARGET_CPU_PPC)

// ************** endian reversal ***************

template <class T>
inline unsigned int GetByte(ByteOrder order, T value, unsigned int index)
{
        if (order == LITTLE_ENDIAN_ORDER)
                return GETBYTE(value, index);
        else
                return GETBYTE(value, sizeof(T)-index-1);
}

inline byte ByteReverse(byte value)
{
        return value;
}

inline word16 ByteReverse(word16 value)
{
#ifdef CRYPTOPP_BYTESWAP_AVAILABLE
        return bswap_16(value);
#elif defined(_MSC_VER) && _MSC_VER >= 1300
        return _byteswap_ushort(value);
#else
        return rotlFixed(value, 8U);
#endif
}

inline word32 ByteReverse(word32 value)
{
#if defined(__GNUC__) && defined(CRYPTOPP_X86_ASM_AVAILABLE)
        __asm__ ("bswap %0" : "=r" (value) : "0" (value));
        return value;
#elif defined(CRYPTOPP_BYTESWAP_AVAILABLE)
        return bswap_32(value);
#elif defined(__MWERKS__) && TARGET_CPU_PPC
        return (word32)__lwbrx(&value,0);
#elif _MSC_VER >= 1400 || (_MSC_VER >= 1300 && !defined(_DLL))
        return _byteswap_ulong(value);
#elif CRYPTOPP_FAST_ROTATE(32)
        // 5 instructions with rotate instruction, 9 without
        return (rotrFixed(value, 8U) & 0xff00ff00) | (rotlFixed(value, 8U) & 0x00ff00ff);
#else
        // 6 instructions with rotate instruction, 8 without
        value = ((value & 0xFF00FF00) >> 8) | ((value & 0x00FF00FF) << 8);
        return rotlFixed(value, 16U);
#endif
}

inline word64 ByteReverse(word64 value)
{
#if defined(__GNUC__) && defined(CRYPTOPP_X86_ASM_AVAILABLE) && defined(__x86_64__)
        __asm__ ("bswap %0" : "=r" (value) : "0" (value));
        return value;
#elif defined(CRYPTOPP_BYTESWAP_AVAILABLE)
        return bswap_64(value);
#elif defined(_MSC_VER) && _MSC_VER >= 1300
        return _byteswap_uint64(value);
#elif CRYPTOPP_BOOL_SLOW_WORD64
        return (word64(ByteReverse(word32(value))) << 32) | ByteReverse(word32(value>>32));
#else
        value = ((value & W64LIT(0xFF00FF00FF00FF00)) >> 8) | ((value & W64LIT(0x00FF00FF00FF00FF)) << 8);
        value = ((value & W64LIT(0xFFFF0000FFFF0000)) >> 16) | ((value & W64LIT(0x0000FFFF0000FFFF)) << 16);
        return rotlFixed(value, 32U);
#endif
}

inline byte BitReverse(byte value)
{
        value = ((value & 0xAA) >> 1) | ((value & 0x55) << 1);
        value = ((value & 0xCC) >> 2) | ((value & 0x33) << 2);
        return rotlFixed(value, 4U);
}

inline word16 BitReverse(word16 value)
{
        value = ((value & 0xAAAA) >> 1) | ((value & 0x5555) << 1);
        value = ((value & 0xCCCC) >> 2) | ((value & 0x3333) << 2);
        value = ((value & 0xF0F0) >> 4) | ((value & 0x0F0F) << 4);
        return ByteReverse(value);
}

inline word32 BitReverse(word32 value)
{
        value = ((value & 0xAAAAAAAA) >> 1) | ((value & 0x55555555) << 1);
        value = ((value & 0xCCCCCCCC) >> 2) | ((value & 0x33333333) << 2);
        value = ((value & 0xF0F0F0F0) >> 4) | ((value & 0x0F0F0F0F) << 4);
        return ByteReverse(value);
}

inline word64 BitReverse(word64 value)
{
#if CRYPTOPP_BOOL_SLOW_WORD64
        return (word64(BitReverse(word32(value))) << 32) | BitReverse(word32(value>>32));
#else
        value = ((value & W64LIT(0xAAAAAAAAAAAAAAAA)) >> 1) | ((value & W64LIT(0x5555555555555555)) << 1);
        value = ((value & W64LIT(0xCCCCCCCCCCCCCCCC)) >> 2) | ((value & W64LIT(0x3333333333333333)) << 2);
        value = ((value & W64LIT(0xF0F0F0F0F0F0F0F0)) >> 4) | ((value & W64LIT(0x0F0F0F0F0F0F0F0F)) << 4);
        return ByteReverse(value);
#endif
}

template <class T>
inline T BitReverse(T value)
{
        if (sizeof(T) == 1)
                return (T)BitReverse((byte)value);
        else if (sizeof(T) == 2)
                return (T)BitReverse((word16)value);
        else if (sizeof(T) == 4)
                return (T)BitReverse((word32)value);
        else
        {
                assert(sizeof(T) == 8);
                return (T)BitReverse((word64)value);
        }
}

template <class T>
inline T ConditionalByteReverse(ByteOrder order, T value)
{
        return NativeByteOrderIs(order) ? value : ByteReverse(value);
}

template <class T>
void ByteReverse(T *out, const T *in, size_t byteCount)
{
        assert(byteCount % sizeof(T) == 0);
        size_t count = byteCount/sizeof(T);
        for (size_t i=0; i<count; i++)
                out[i] = ByteReverse(in[i]);
}

template <class T>
inline void ConditionalByteReverse(ByteOrder order, T *out, const T *in, size_t byteCount)
{
        if (!NativeByteOrderIs(order))
                ByteReverse(out, in, byteCount);
        else if (in != out)
                memcpy_s(out, byteCount, in, byteCount);
}

template <class T>
inline void GetUserKey(ByteOrder order, T *out, size_t outlen, const byte *in, size_t inlen)
{
        const size_t U = sizeof(T);
        assert(inlen <= outlen*U);
        memcpy_s(out, outlen*U, in, inlen);
        memset_z((byte *)out+inlen, 0, outlen*U-inlen);
        ConditionalByteReverse(order, out, out, RoundUpToMultipleOf(inlen, U));
}

#ifndef CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS
inline byte UnalignedGetWordNonTemplate(ByteOrder order, const byte *block, const byte *)
{
        return block[0];
}

inline word16 UnalignedGetWordNonTemplate(ByteOrder order, const byte *block, const word16 *)
{
        return (order == BIG_ENDIAN_ORDER)
                ? block[1] | (block[0] << 8)
                : block[0] | (block[1] << 8);
}

inline word32 UnalignedGetWordNonTemplate(ByteOrder order, const byte *block, const word32 *)
{
        return (order == BIG_ENDIAN_ORDER)
                ? word32(block[3]) | (word32(block[2]) << 8) | (word32(block[1]) << 16) | (word32(block[0]) << 24)
                : word32(block[0]) | (word32(block[1]) << 8) | (word32(block[2]) << 16) | (word32(block[3]) << 24);
}

inline word64 UnalignedGetWordNonTemplate(ByteOrder order, const byte *block, const word64 *)
{
        return (order == BIG_ENDIAN_ORDER)
                ?
                (word64(block[7]) |
                (word64(block[6]) <<  8) |
                (word64(block[5]) << 16) |
                (word64(block[4]) << 24) |
                (word64(block[3]) << 32) |
                (word64(block[2]) << 40) |
                (word64(block[1]) << 48) |
                (word64(block[0]) << 56))
                :
                (word64(block[0]) |
                (word64(block[1]) <<  8) |
                (word64(block[2]) << 16) |
                (word64(block[3]) << 24) |
                (word64(block[4]) << 32) |
                (word64(block[5]) << 40) |
                (word64(block[6]) << 48) |
                (word64(block[7]) << 56));
}

inline void UnalignedPutWordNonTemplate(ByteOrder order, byte *block, byte value, const byte *xorBlock)
{
        block[0] = xorBlock ? (value ^ xorBlock[0]) : value;
}

inline void UnalignedPutWordNonTemplate(ByteOrder order, byte *block, word16 value, const byte *xorBlock)
{
        if (order == BIG_ENDIAN_ORDER)
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
        }
        else
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                }
        }
}

inline void UnalignedPutWordNonTemplate(ByteOrder order, byte *block, word32 value, const byte *xorBlock)
{
        if (order == BIG_ENDIAN_ORDER)
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[2] = xorBlock[2] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[3] = xorBlock[3] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[2] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[3] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
        }
        else
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[2] = xorBlock[2] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[3] = xorBlock[3] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[2] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[3] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                }
        }
}

inline void UnalignedPutWordNonTemplate(ByteOrder order, byte *block, word64 value, const byte *xorBlock)
{
        if (order == BIG_ENDIAN_ORDER)
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 7);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 6);
                        block[2] = xorBlock[2] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 5);
                        block[3] = xorBlock[3] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 4);
                        block[4] = xorBlock[4] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[5] = xorBlock[5] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[6] = xorBlock[6] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[7] = xorBlock[7] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 7);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 6);
                        block[2] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 5);
                        block[3] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 4);
                        block[4] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[5] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[6] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[7] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                }
        }
        else
        {
                if (xorBlock)
                {
                        block[0] = xorBlock[0] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = xorBlock[1] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[2] = xorBlock[2] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[3] = xorBlock[3] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[4] = xorBlock[4] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 4);
                        block[5] = xorBlock[5] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 5);
                        block[6] = xorBlock[6] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 6);
                        block[7] = xorBlock[7] ^ CRYPTOPP_GET_BYTE_AS_BYTE(value, 7);
                }
                else
                {
                        block[0] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 0);
                        block[1] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 1);
                        block[2] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 2);
                        block[3] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 3);
                        block[4] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 4);
                        block[5] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 5);
                        block[6] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 6);
                        block[7] = CRYPTOPP_GET_BYTE_AS_BYTE(value, 7);
                }
        }
}
#endif  // #ifndef CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS

template <class T>
inline T GetWord(bool assumeAligned, ByteOrder order, const byte *block)
{
#ifndef CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS
        if (!assumeAligned)
                return UnalignedGetWordNonTemplate(order, block, (T*)NULL);
        assert(IsAligned<T>(block));
#endif
        return ConditionalByteReverse(order, *reinterpret_cast<const T *>(block));
}

template <class T>
inline void GetWord(bool assumeAligned, ByteOrder order, T &result, const byte *block)
{
        result = GetWord<T>(assumeAligned, order, block);
}

template <class T>
inline void PutWord(bool assumeAligned, ByteOrder order, byte *block, T value, const byte *xorBlock = NULL)
{
#ifndef CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS
        if (!assumeAligned)
                return UnalignedPutWordNonTemplate(order, block, value, xorBlock);
        assert(IsAligned<T>(block));
        assert(IsAligned<T>(xorBlock));
#endif
        *reinterpret_cast<T *>(block) = ConditionalByteReverse(order, value) ^ (xorBlock ? *reinterpret_cast<const T *>(xorBlock) : 0);
}

template <class T, class B, bool A=false>
class GetBlock
{
public:
        GetBlock(const void *block)
                : m_block((const byte *)block) {}

        template <class U>
        inline GetBlock<T, B, A> & operator()(U &x)
        {
                CRYPTOPP_COMPILE_ASSERT(sizeof(U) >= sizeof(T));
                x = GetWord<T>(A, B::ToEnum(), m_block);
                m_block += sizeof(T);
                return *this;
        }

private:
        const byte *m_block;
};

template <class T, class B, bool A=false>
class PutBlock
{
public:
        PutBlock(const void *xorBlock, void *block)
                : m_xorBlock((const byte *)xorBlock), m_block((byte *)block) {}

        template <class U>
        inline PutBlock<T, B, A> & operator()(U x)
        {
                PutWord(A, B::ToEnum(), m_block, (T)x, m_xorBlock);
                m_block += sizeof(T);
                if (m_xorBlock)
                        m_xorBlock += sizeof(T);
                return *this;
        }

private:
        const byte *m_xorBlock;
        byte *m_block;
};

template <class T, class B, bool GA=false, bool PA=false>
struct BlockGetAndPut
{
        // function needed because of C++ grammatical ambiguity between expression-statements and declarations
        static inline GetBlock<T, B, GA> Get(const void *block) {return GetBlock<T, B, GA>(block);}
        typedef PutBlock<T, B, PA> Put;
};

template <class T>
std::string WordToString(T value, ByteOrder order = BIG_ENDIAN_ORDER)
{
        if (!NativeByteOrderIs(order))
                value = ByteReverse(value);

        return std::string((char *)&value, sizeof(value));
}

template <class T>
T StringToWord(const std::string &str, ByteOrder order = BIG_ENDIAN_ORDER)
{
        T value = 0;
        memcpy_s(&value, sizeof(value), str.data(), UnsignedMin(str.size(), sizeof(value)));
        return NativeByteOrderIs(order) ? value : ByteReverse(value);
}

// ************** help remove warning on g++ ***************

template <bool overflow> struct SafeShifter;

template<> struct SafeShifter<true>
{
        template <class T>
        static inline T RightShift(T value, unsigned int bits)
        {
                return 0;
        }

        template <class T>
        static inline T LeftShift(T value, unsigned int bits)
        {
                return 0;
        }
};

template<> struct SafeShifter<false>
{
        template <class T>
        static inline T RightShift(T value, unsigned int bits)
        {
                return value >> bits;
        }

        template <class T>
        static inline T LeftShift(T value, unsigned int bits)
        {
                return value << bits;
        }
};

template <unsigned int bits, class T>
inline T SafeRightShift(T value)
{
        return SafeShifter<(bits>=(8*sizeof(T)))>::RightShift(value, bits);
}

template <unsigned int bits, class T>
inline T SafeLeftShift(T value)
{
        return SafeShifter<(bits>=(8*sizeof(T)))>::LeftShift(value, bits);
}

// ************** use one buffer for multiple data members ***************

#define CRYPTOPP_BLOCK_1(n, t, s) t* m_##n() {return (t *)(m_aggregate+0);}     size_t SS1() {return       sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_2(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS1());} size_t SS2() {return SS1()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_3(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS2());} size_t SS3() {return SS2()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_4(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS3());} size_t SS4() {return SS3()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_5(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS4());} size_t SS5() {return SS4()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_6(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS5());} size_t SS6() {return SS5()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_7(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS6());} size_t SS7() {return SS6()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCK_8(n, t, s) t* m_##n() {return (t *)(m_aggregate+SS7());} size_t SS8() {return SS7()+sizeof(t)*(s);} size_t m_##n##Size() {return (s);}
#define CRYPTOPP_BLOCKS_END(i) size_t SST() {return SS##i();} void AllocateBlocks() {m_aggregate.New(SST());} AlignedSecByteBlock m_aggregate;

NAMESPACE_END

#endif