misc.cpp

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// misc.cpp - written and placed in the public domain by Wei Dai

#include "pch.h"
#include "config.h"

#if CRYPTOPP_MSC_VERSION
# pragma warning(disable: 4189)
# if (CRYPTOPP_MSC_VERSION >= 1400)
#  pragma warning(disable: 6237)
# endif
#endif

#ifndef CRYPTOPP_IMPORTS

#include "misc.h"
#include "words.h"
#include "words.h"
#include "stdcpp.h"
#include "integer.h"

// for memalign
#if defined(CRYPTOPP_MEMALIGN_AVAILABLE) || defined(CRYPTOPP_MM_MALLOC_AVAILABLE) || defined(QNX)
# include <malloc.h>
#endif

NAMESPACE_BEGIN(CryptoPP)

void xorbuf(byte *buf, const byte *mask, size_t count)
{
        CRYPTOPP_ASSERT(buf != NULL);
        CRYPTOPP_ASSERT(mask != NULL);
        CRYPTOPP_ASSERT(count > 0);

        size_t i=0;
        if (IsAligned<word32>(buf) && IsAligned<word32>(mask))
        {
                if (!CRYPTOPP_BOOL_SLOW_WORD64 && IsAligned<word64>(buf) && IsAligned<word64>(mask))
                {
                        for (i=0; i<count/8; i++)
                                ((word64*)(void*)buf)[i] ^= ((word64*)(void*)mask)[i];
                        count -= 8*i;
                        if (!count)
                                return;
                        buf += 8*i;
                        mask += 8*i;
                }

                for (i=0; i<count/4; i++)
                        ((word32*)(void*)buf)[i] ^= ((word32*)(void*)mask)[i];
                count -= 4*i;
                if (!count)
                        return;
                buf += 4*i;
                mask += 4*i;
        }

        for (i=0; i<count; i++)
                buf[i] ^= mask[i];
}

void xorbuf(byte *output, const byte *input, const byte *mask, size_t count)
{
        CRYPTOPP_ASSERT(output != NULL);
        CRYPTOPP_ASSERT(input != NULL);
        CRYPTOPP_ASSERT(count > 0);

        size_t i=0;
        if (IsAligned<word32>(output) && IsAligned<word32>(input) && IsAligned<word32>(mask))
        {
                if (!CRYPTOPP_BOOL_SLOW_WORD64 && IsAligned<word64>(output) && IsAligned<word64>(input) && IsAligned<word64>(mask))
                {
                        for (i=0; i<count/8; i++)
                                ((word64*)(void*)output)[i] = ((word64*)(void*)input)[i] ^ ((word64*)(void*)mask)[i];
                        count -= 8*i;
                        if (!count)
                                return;
                        output += 8*i;
                        input += 8*i;
                        mask += 8*i;
                }

                for (i=0; i<count/4; i++)
                        ((word32*)(void*)output)[i] = ((word32*)(void*)input)[i] ^ ((word32*)(void*)mask)[i];
                count -= 4*i;
                if (!count)
                        return;
                output += 4*i;
                input += 4*i;
                mask += 4*i;
        }

        for (i=0; i<count; i++)
                output[i] = input[i] ^ mask[i];
}

bool VerifyBufsEqual(const byte *buf, const byte *mask, size_t count)
{
        CRYPTOPP_ASSERT(buf != NULL);
        CRYPTOPP_ASSERT(mask != NULL);
        CRYPTOPP_ASSERT(count > 0);

        size_t i=0;
        byte acc8 = 0;

        if (IsAligned<word32>(buf) && IsAligned<word32>(mask))
        {
                word32 acc32 = 0;
                if (!CRYPTOPP_BOOL_SLOW_WORD64 && IsAligned<word64>(buf) && IsAligned<word64>(mask))
                {
                        word64 acc64 = 0;
                        for (i=0; i<count/8; i++)
                                acc64 |= ((word64*)(void*)buf)[i] ^ ((word64*)(void*)mask)[i];
                        count -= 8*i;
                        if (!count)
                                return acc64 == 0;
                        buf += 8*i;
                        mask += 8*i;
                        acc32 = word32(acc64) | word32(acc64>>32);
                }

                for (i=0; i<count/4; i++)
                        acc32 |= ((word32*)(void*)buf)[i] ^ ((word32*)(void*)mask)[i];
                count -= 4*i;
                if (!count)
                        return acc32 == 0;
                buf += 4*i;
                mask += 4*i;
                acc8 = byte(acc32) | byte(acc32>>8) | byte(acc32>>16) | byte(acc32>>24);
        }

        for (i=0; i<count; i++)
                acc8 |= buf[i] ^ mask[i];
        return acc8 == 0;
}

std::string StringNarrow(const wchar_t *str, bool throwOnError)
{
        CRYPTOPP_ASSERT(str);
        std::string result;

        // Safer functions on Windows for C&A, https://github.com/weidai11/cryptopp/issues/55
#if (CRYPTOPP_MSC_VERSION >= 1400)
        size_t len=0, size=0;
        errno_t err = 0;

        //const wchar_t* ptr = str;
        //while (*ptr++) len++;
        len = wcslen(str)+1;

        err = wcstombs_s(&size, NULL, 0, str, len*sizeof(wchar_t));
        CRYPTOPP_ASSERT(err == 0);
        if (err != 0)
        {
                if (throwOnError)
                        throw InvalidArgument("StringNarrow: wcstombs_s() call failed with error " + IntToString(err));
                else
                        return std::string();
        }

        result.resize(size);
        err = wcstombs_s(&size, &result[0], size, str, len*sizeof(wchar_t));
        CRYPTOPP_ASSERT(err == 0);
        if (err != 0)
        {
                if (throwOnError)
                        throw InvalidArgument("StringNarrow: wcstombs_s() call failed with error " + IntToString(err));
                else
                        return std::string();
        }

        // The safe routine's size includes the NULL.
        if (!result.empty() && result[size - 1] == '\0')
                result.erase(size - 1);
#else
        size_t size = wcstombs(NULL, str, 0);
        CRYPTOPP_ASSERT(size != (size_t)-1);
        if (size == (size_t)-1)
        {
                if (throwOnError)
                        throw InvalidArgument("StringNarrow: wcstombs() call failed");
                else
                        return std::string();
        }

        result.resize(size);
        size = wcstombs(&result[0], str, size);
        CRYPTOPP_ASSERT(size != (size_t)-1);
        if (size == (size_t)-1)
        {
                if (throwOnError)
                        throw InvalidArgument("StringNarrow: wcstombs() call failed");
                else
                        return std::string();
        }
#endif

        return result;
}

void CallNewHandler()
{
        using std::new_handler;
        using std::set_new_handler;

        new_handler newHandler = set_new_handler(NULL);
        if (newHandler)
                set_new_handler(newHandler);

        if (newHandler)
                newHandler();
        else
                throw std::bad_alloc();
}

#if CRYPTOPP_BOOL_ALIGN16

void * AlignedAllocate(size_t size)
{
        byte *p;
#if defined(CRYPTOPP_APPLE_ALLOC_AVAILABLE)
        while ((p = (byte *)calloc(1, size)) == NULL)
#elif defined(CRYPTOPP_MM_MALLOC_AVAILABLE)
        while ((p = (byte *)_mm_malloc(size, 16)) == NULL)
#elif defined(CRYPTOPP_MEMALIGN_AVAILABLE)
        while ((p = (byte *)memalign(16, size)) == NULL)
#elif defined(CRYPTOPP_MALLOC_ALIGNMENT_IS_16)
        while ((p = (byte *)malloc(size)) == NULL)
#else
        while ((p = (byte *)malloc(size + 16)) == NULL)
#endif
                CallNewHandler();

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

        CRYPTOPP_ASSERT(IsAlignedOn(p, 16));
        return p;
}

void AlignedDeallocate(void *p)
{
#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
}

#endif

void * UnalignedAllocate(size_t size)
{
        void *p;
        while ((p = malloc(size)) == NULL)
                CallNewHandler();
        return p;
}

void UnalignedDeallocate(void *p)
{
        free(p);
}

NAMESPACE_END

#endif