ARPScanExample

    // ------------------------------- //
    // -------- Start of File -------- //
    // ------------------------------- //
    // ----------------------------------------------------------- //
    // C++ Source Code File Name: arpscan.cpp
    // C++ Compiler Used: MSVC, BCC32, GCC, HPUX aCC, SOLARIS CC
    // Produced By: DataReel Software Development Team
    // File Creation Date: 09/20/1999
    // Date Last Modified: 06/17/2016
    // Copyright (c) 2001-2016 DataReel Software Development
    // ----------------------------------------------------------- //
    // ------------- Program Description and Details ------------- //
    // ----------------------------------------------------------- //
    /*
    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
    USA

    Test program used to get the Media Access Control (MAC) addresses
    of all the hosts on a specified class C subnet.
    */
    // ----------------------------------------------------------- //
    #include "gxdlcode.h"

    #if defined (__USE_ANSI_CPP__) // Use the ANSI Standard C++ library
    #include <iostream>
    #include <fstream>
    using namespace std; // Use unqualified names for Standard C++ library
    #else // Use the old iostream library by default
    #include <iostream.h>
    #include <fstream.h>
    #endif // __USE_ANSI_CPP__

    #include <string.h>
    #include <stdio.h>
    #include <time.h>
    #include <stdlib.h>
    #include "gxsping.h"
    #include "gxip32.h"
    #include "gxmac48.h"

    // Platform specific include files
    #if defined (__UNIX__)
    #include <net/if_arp.h>
    #include <sys/ioctl.h>
    #endif

    #if defined (__WIN32__)
    int WIN32GetMAC(const char *ip_address, char *mac_address);
    #endif

    int GetMacAddress(const char *ip_address, char *eth_dev, char *fname = 0,
    		  fstream *outfile = 0)
    {
      // Construct a raw socket;
      gxSocket raw_socket;
      if(raw_socket.InitSocketLibrary() != 0) {
        cout << raw_socket.SocketExceptionMessage() << "\n" << flush;
        if(outfile)
          *(outfile) << raw_socket.SocketExceptionMessage() << "\n" << flush;
        return 0;
      }
      cout << ip_address << '\t' << flush;
      if(outfile) *(outfile) << ip_address << '\t' << flush;
      gxsHostNameInfo *hostnm = raw_socket.GetHostInformation((char *)ip_address);
      if(hostnm) {
        cout << hostnm->h_name << flush;
        if(outfile) *(outfile) << hostnm->h_name << flush;
      }
      else {
        cout << "no_DNS_entry" << flush;
       if(outfile) *(outfile) << "no_DNS_entry" << flush;
      }

      if(raw_socket.InitSocket(AF_INET, SOCK_RAW, IPPROTO_ICMP, 0,
    			   (char *)ip_address) < 0) {
        cout << raw_socket.SocketExceptionMessage() << "\n" << flush;
        if(outfile)
          *(outfile) << raw_socket.SocketExceptionMessage() << "\n" << flush;
        return 0;
      }

      // Ping with a specified timeout value
      gxsPing ping(&raw_socket);
      if(ping.Ping(4) != gxSOCKET_NO_ERROR) {
        if(raw_socket.GetSocketError() == gxSOCKET_REQUEST_TIMEOUT) {
        }
        else {
          cout << "\n" << flush;
          cout << raw_socket.SocketExceptionMessage() << "\n" << flush;
          if(outfile) {
    	*(outfile) << "\n" << flush;
    	*(outfile) << raw_socket.SocketExceptionMessage() << "\n" << flush;
          }
          delete hostnm;
          return 0;
        }
      }

    #if defined (__WIN32__)
      char mac_address[255];
      if(!WIN32GetMAC(ip_address, mac_address)) {
        cout << "\n" << flush;
        if(outfile) *(outfile) << "\n" << flush;
        delete hostnm;
        return 0; // No entry in the arp cache
      }
      gxMAC48 mac(mac_address, '-', 2);
      cout << '\t' << mac.c_str(mac_address) << flush;
      if(outfile) *(outfile) << '\t' << mac.c_str(mac_address) << flush;
    #elif defined (__UNIX__)
      arpreq arp_data;
      memset(&arp_data, 0, sizeof(arp_data));
      memcpy(&arp_data.arp_pa, &raw_socket.sin, sizeof(arp_data.arp_pa));

    #if defined (__LINUX__)
      strcpy(arp_data.arp_dev, eth_dev);
    #endif

    #ifndef SIOCGARP
    #error SIOCGARP is not available on this platform
    #endif

      if(ioctl(raw_socket.GetSocket(), SIOCGARP, &arp_data) == -1) {
        cout << "\n" << flush;
        if(outfile) *(outfile) << "\n" << flush;
        delete hostnm;
        return 0; // No entry in the arp cache
      }

      char mac_address[255];
      unsigned char *ptr = (unsigned char *)&arp_data.arp_ha.sa_data[0];
      sprintf(mac_address, "%.2X:%.2X:%.2X:%.2X:%.2X:%.2X",*ptr,
    	  *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5));

      gxMAC48 mac(mac_address, ':', 2);
      cout << '\t' << mac.c_str(mac_address) << flush;
      if(outfile) *(outfile) << '\t' << mac.c_str(mac_address) << flush;
    #else
    #error You must define a target platform: __WIN32__ or __UNIX__
    #endif

      if(fname) { // Find the vendor information
        char name[255];
        char comment[255];
        if(FindVendor((const char *)fname, mac, name, comment)) {
          cout << '\t' << name << flush;
          if(outfile) *(outfile) << '\t' << name << flush;
        }
      }
      cout << "\n" << flush;
      if(outfile) *(outfile) << "\n" << flush;
      delete hostnm;
      return 1;
    }

    int main(int argc, char **argv)
    {
    #ifdef __UNIX__
      // Raw sockets require root access on all UNIX platforms. Programs
      // that use raw sockets can be executed by non-root users if the
      // effective user ID of the executing process is set to the same as
      // the file's owner. In the case root must own the executable and
      // the effective User-ID or Group-ID on execution bit must be set
      // by root using the chmod command: "chmod u+s" or "chmod 4755"
      // Now the effective user ID of the executing process will be set to
      // the same user ID of the file's owner.
      if(geteuid() != 0) {
        cout << "You must be root to run this program" << "\n";
        return 0;
      }
    #endif

      // Check the command line arguments
    #if defined (__WIN32__)
      if(argc < 2) {
        cout << "\n";
        cout << "Usage: " << argv[0] << " subnet " << "\n";
        cout << "Example 1: " << argv[0] <<" 192.168.0 " << "\n";
        cout << "Example 2: " << argv[0] <<" 192.168.0 maccodes.txt" << "\n";
        cout << "Example 3: " << argv[0] <<" 192.168.0.1 " << "\n";
        cout << "Example 4: " << argv[0] <<" 192.168.0.1 maccodes.txt" << "\n";
        cout << "Example 5: " << argv[0] <<" 192.168.0.255 maccodes.txt \
    outfile.txt" << "\n";
        return 1;
      }
      char *subnet = argv[1];
      char *eth_dev = 0;
      char *fname = 0;
      char *ofname = 0;
      if(argc >= 3) fname = argv[2];
      if(argc == 4) ofname = argv[3];
    #elif defined (__UNIX__)
      if(argc < 3) {
        cout << "\n";
        cout << "Usage: " << argv[0] << " subnet ethernet_device" << "\n";
        cout << "Example 1: " << argv[0] <<" 192.168.0 eth0" << "\n";
        cout << "Example 2: " << argv[0] <<" 192.168.0 eth0 maccodes.txt"
    	 << "\n";
        cout << "Example 3: " << argv[0] <<" 192.168.0.1 eth0" << "\n";
        cout << "Example 4: " << argv[0] <<" 192.168.0.1 eth0 maccodes.txt"
    	 << "\n";
        cout << "Example 5: " << argv[0] <<" 192.168.0.255 eth0 maccodes.txt \
    outfile.txt" << "\n";
        return 1;
      }
      char *subnet = argv[1];
      char *eth_dev = argv[2];
      char *fname = 0;
      char *ofname = 0;
      if(argc >= 4) fname = argv[3];
      if(argc == 5) fname = argv[4];
    #else
    #error You must define a target platform: __WIN32__ or __UNIX__
    #endif

      fstream outfile;
      int out = 0;
      if(ofname) {
        // Open the output file and truncate if it already exists
        out = 1;
        outfile.open(ofname, ios::out|ios::trunc|ios::binary);
        if(!outfile) {
          cout << "Could not open the " << ofname << " output file" << "\n";
          return 1;
        }
      }

      gxIP32 ip32(subnet);
      char sbuf[255];
      if((ip32.GetByte4() == 0) || (ip32.GetByte4() == 255)) {
        // Find the mac address of all the nodes on a specified subnet
        for(int i = 1; i < 255; i++) {
          ip32.SetByte4(i);
          if(out)
    	GetMacAddress(ip32.c_str(sbuf), eth_dev, fname, &outfile);
          else
    	GetMacAddress(ip32.c_str(sbuf), eth_dev, fname);
        }
      }
      else {
        // Get the mac address of a single node
        if(out)
          GetMacAddress(ip32.c_str(sbuf), eth_dev, fname, &outfile);
        else
          GetMacAddress(ip32.c_str(sbuf), eth_dev, fname);
      }

      if(out) outfile.close();
      return 0;
    }

    #if defined (__WIN32__)
    int WIN32GetMAC(const char *ip_address, char *mac_address)
    // Function used to get a mac address from the WIN32 arp cache.
    // Returns true if an arp cache entry exists for the specified
    // IP address string.
    {
      system("arp -a > arpcache.txt");
      ifstream infile("arpcache.txt", ios::in);
      if(!infile) return 0; // Cannot open the file

      char sbuf[255];
      char ip_in[255];

      while(!infile.eof()) {
        infile.getline(sbuf, 255);
        int len, offset, i = 0;
        int byte_count = strlen(sbuf);
        ip_in[0] = 0;
        mac_address[0] = 0;

        // Trim leading tabs and spaces
        while((sbuf[i] == ' ') || (sbuf[i] == '\t')) i++;
        byte_count -= i;
        if(byte_count <= 0) continue;
        memmove(sbuf, sbuf+i, byte_count);
        sbuf[byte_count] = 0;

        // Parse the IP Address
        for(i = 0; i < byte_count; i ++) {
          if((sbuf[i] == ' ') || (sbuf[i] == '\t')) break;
          ip_in[i] = sbuf[i];
        }
        ip_in[i] = 0; // Null terminate the string

        if(strcmp(ip_in, ip_address) == 0) { // Parse the MAC Address
          while((sbuf[i] == ' ') || (sbuf[i] == '\t')) i++;
          byte_count -= i;
          if(byte_count <= 0) continue;
          memmove(sbuf, sbuf+i, byte_count);
          for(i = 0; i < byte_count; i ++) {
    	if(sbuf[i] == ' ') break;
    	mac_address[i] = sbuf[i];
          }
          mac_address[i] = 0; // Null terminate the string

          if(mac_address[0] != 0)  { // Remove any trailing spaces
    	offset = len = strlen(mac_address);
    	while(offset--) if(mac_address[offset] != ' ') break;
    	if(offset < len) mac_address[offset+1] = 0;
    	return 1; // Found the arp cache entry
          }
          else {
    	return 0;
          }
        }
      }
      infile.close();
      return 0;
    }
    #endif
    // ----------------------------------------------------------- //
    // ------------------------------- //
    // --------- End of File --------- //
    // ------------------------------- //