Create magic packet on C++

Question

I'm trying to crate a Magic Packet to apply WOL on a certain PC, I tried to do it in the same format exactly like the packet looks in a Wireshark capture, but the PC doesn't recognize the receiving packet as a magic packet

here is the code:

UINT8*  CTestCase::CreateMagicPacket(IN OUT UINT8* p_buffer, IN int  size, IN MACAddress src, IN MACAddress dst)
{

    UINT8 *my_buff_to_send = new UINT8[size]{ 0 }; //create new buffer with the size we want


    for (int i = 0; i < 6; i++) //broadcast address
    {
        my_buff_to_send[i] = 0xFF;
        m_pLog->AddMessage(" |");
        m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
    }

    int m = 5;
    for (size_t i = 6; i < 12; i++) //insert source mac adress to the new buffer
    {

            my_buff_to_send[i] = src.Get(m);
            m_pLog->AddMessage(" |");
            m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
            m--;
    }


    my_buff_to_send[12] = 0x08;
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[12]));
    my_buff_to_send[13] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[13]));
    my_buff_to_send[14] =  0x45;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[14]));
    my_buff_to_send[15] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[15]));
    my_buff_to_send[16] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[16]));
    my_buff_to_send[17] =  0x90;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[17]));
    my_buff_to_send[18] = 0x48;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[18]));
    my_buff_to_send[19] = 0x91;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[19]));
    my_buff_to_send[20] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[20]));
    my_buff_to_send[21] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[21]));
    my_buff_to_send[22] = 0x80;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[22]));
    my_buff_to_send[23] = 0x11;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[23]));
    my_buff_to_send[24] = 0x00;  //insert permanent type to the buffer OR dd
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[24]));
    my_buff_to_send[25] = 0x00;  //insert permanent type to the buffer OR bd
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[25]));
    my_buff_to_send[26] = 0x0a;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[26]));
    my_buff_to_send[27] = 0x0a;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[27]));
    my_buff_to_send[28] = 0x0a;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[28]));
    my_buff_to_send[29] = 0x05;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[29]));
    my_buff_to_send[30] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[30]));
    my_buff_to_send[31] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[31]));
    my_buff_to_send[32] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[32]));
    my_buff_to_send[33] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[33]));
    my_buff_to_send[34] = 0xd0;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[34]));
    my_buff_to_send[35] = 0x28;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[35]));
    my_buff_to_send[36] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[36]));
    my_buff_to_send[37] = 0xff;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[37]));
    my_buff_to_send[38] = 0x00;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[38]));
    my_buff_to_send[39] = 0x7c;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[39]));
    my_buff_to_send[40] = 0x14;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[40]));
    my_buff_to_send[41] = 0x9c;  //insert permanent type to the buffer
    m_pLog->AddMessage(" |");
    m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[41]));



    for (int i = 42; i < 48; i++)
    {
        my_buff_to_send[i] = 0xFF;
        m_pLog->AddMessage(" |");
        m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
    }

    int r = 5;
    for (size_t i = 48; i < 54; i++) //insert source mac adress to the new buffer
    {
        my_buff_to_send[i] = dst.Get(r);
        m_pLog->AddMessage(" |");
        m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
        r--;
    }

    for (int i = 54; i < 60; i++)
    {
        my_buff_to_send[i] = 0xFF;
        m_pLog->AddMessage(" |");
        m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
    }


    for (size_t j = 0; j < 16; j++)
    {

        for (int k = 5; k >= 0; k--) //insert destination mac adress to the buffer
        {
            int i = 60;
            my_buff_to_send[i] = dst.Get(k);

            m_pLog->AddMessage(" |");
            m_pLog->AddMessage("%d ", UINT32(my_buff_to_send[i]));
            i++;
        }

    }


            return my_buff_to_send;




};

Unrelated to the actual functionality, but can't you just log the whole message data at once in the end? Those intermixed log lines are extremely distracting, and, being all around the code, I wouldn't be surprised that at least one of them is wrong for some trivial copy/paste error. — Matteo Italia, Jun 11 '18 at 06:26

Jerry Coffin · Answer 1 · 2018-06-11T08:52:24.933

Do you really need to create a raw Ethernet packet on your own?

When I've done this, I've just embedded the magic packet into something like a UDP packet, and broadcast that. For example:

#include "sock2/sock2.h"

int main() { 
    std::string MAC_address("\x00\x00\x00\x00\x00\x00", 6);
    std::string buffer("\xff\xff\xff\xff\xff\xff");

    for (int i=0; i<16; i++)
        buffer.append(MAC_address);

    IP::UDP::socket s;
    s.setopt(SO_BROADCAST);

    IP::address addr(192, 168, 0, 255, 5);
    s.send(buffer, addr);
}

That's pretty minimalist (e.g., hard-coded addresses, virtually no error checking), but with appropriate bytes for the MAC address works just fine. I didn't try to analyze all your code in detail, but it does seem to include quite a lot more than I'd expect should normally be necessary.

Create magic packet on C++

1 Answers1