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C ++ Strange hex dump of WSAsend packages

http://prntscr.com/2ctnoz

I plug in the WSAsend function and drop the packets. ASCII dump works, but DEX Dump sometimes shows things you can see on the screen (FFFFFFDD), any idea why?

code:

int WINAPI myWSASend(SOCKET s, LPWSABUF lpBuffers, DWORD dwBufferCount, LPDWORD lpNumberOfBytesSent, DWORD dwFlags, LPWSAOVERLAPPED lpOverlapped, LPWSAOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine)
{   
    //Packet Log
    if (bLogPacketS == TRUE)
    {
        for (unsigned int i = 0; i < lpBuffers->len; i = i + 8)
        {
            printf("%02X %02X %02X %02X %02X %02X %02X %02X\t\t%c %c %c %c %c %c %c %c\n",
                  (unsigned int)lpBuffers->buf[i], (unsigned int)lpBuffers->buf[i+1], (unsigned int)lpBuffers->buf[i+2],
                  (unsigned int)lpBuffers->buf[i+3], (unsigned int)lpBuffers->buf[i+4], (unsigned int)lpBuffers->buf[i+5],
                  (unsigned int)lpBuffers->buf[i+6], (unsigned int)lpBuffers->buf[i+7],
                  (drawable((unsigned int)lpBuffers->buf[i])) ? (unsigned int)lpBuffers->buf[i] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+1])) ? (unsigned int)lpBuffers->buf[i+1] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+2])) ? (unsigned int)lpBuffers->buf[i+2] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+3])) ? (unsigned int)lpBuffers->buf[i+3] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+4])) ? (unsigned int)lpBuffers->buf[i+4] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+5])) ? (unsigned int)lpBuffers->buf[i+5] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+6])) ? (unsigned int)lpBuffers->buf[i+6] : '.',
                  (drawable((unsigned int)lpBuffers->buf[i+7])) ? (unsigned int)lpBuffers->buf[i+7] : '.');
        }
        printf("\n\n");
    }
    return (oWSASend)(s, lpBuffers, dwBufferCount, lpNumberOfBytesSent, dwFlags, lpOverlapped, lpCompletionRoutine);
}

bool drawable(unsigned int value)
{
    if (value > 32 && value < 127)
        return true;
    else
        return false;
}
+4
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1 answer

You produce the wrong type.

You want to change the signature, but you also expand each byte into a four-byte word. In the presence of unsigned conversion (and the resulting negative value), this leads to a monstrously high cost.

"" lpBuffers->buf[i] char, unsigned int. char , 0xDD , -35. unsigned int 0xFFFFFFDD.

printf %02X .

, unsigned, 0x00 → 0xFF. unsigned char ( unsigned int), 0xDD 221.

.

for (unsigned int i = 0; i < lpBuffers->len-8; i = i + 8)
//                                         ^^
{
    printf(
        "%02X %02X %02X %02X %02X %02X %02X %02X"
          "\t\t%c %c %c %c %c %c %c %c\n",

        static_cast<unsigned char>(lpBuffers->buf[i]),
        static_cast<unsigned char>(lpBuffers->buf[i+1]),
        static_cast<unsigned char>(lpBuffers->buf[i+2]),
        static_cast<unsigned char>(lpBuffers->buf[i+3]),
        static_cast<unsigned char>(lpBuffers->buf[i+4]),
        static_cast<unsigned char>(lpBuffers->buf[i+5]),
        static_cast<unsigned char>(lpBuffers->buf[i+6]),
        static_cast<unsigned char>(lpBuffers->buf[i+7]),
        (drawable(lpBuffers->buf[i]))   ? static_cast<unsigned char>(lpBuffers->buf[i])   : '.',
        (drawable(lpBuffers->buf[i+1])) ? static_cast<unsigned char>(lpBuffers->buf[i+1]) : '.',
        (drawable(lpBuffers->buf[i+2])) ? static_cast<unsigned char>(lpBuffers->buf[i+2]) : '.',
        (drawable(lpBuffers->buf[i+3])) ? static_cast<unsigned char>(lpBuffers->buf[i+3]) : '.',
        (drawable(lpBuffers->buf[i+4])) ? static_cast<unsigned char>(lpBuffers->buf[i+4]) : '.',
        (drawable(lpBuffers->buf[i+5])) ? static_cast<unsigned char>(lpBuffers->buf[i+5]) : '.',
        (drawable(lpBuffers->buf[i+6])) ? static_cast<unsigned char>(lpBuffers->buf[i+6]) : '.',
        (drawable(lpBuffers->buf[i+7])) ? static_cast<unsigned char>(lpBuffers->buf[i+7]) : '.'
    );
}
+3

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