statystyki pseciowe

/*
 * Copyright (C) 2019 Michal Kalewski <mkalewski at cs.put.poznan.pl>
 *
 * Compilation:  gcc -Wall ./pcapsniff.c -o ./pcapsniff -lpcap
 * Usage:        ./pcapsniff INTERFACE
 * NOTE:         This program requires root privileges.
 *
 * Bug reports:  https://gitlab.cs.put.poznan.pl/mkalewski/ps-2019/issues
 *
 */

#include <pcap.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <linux/if_ether.h>
#include <linux/ip.h>
#include <linux/types.h>

char* errbuf;
pcap_t* handle;

struct stats {
    long arp;
    long ip;
    long ip_udp;
    long ip_tcp;
    long inne;
};

struct stats staty;
void resetStaty(){
  staty.arp = 0;
  staty.ip = 0;
  staty.ip_udp = 0;
  staty.ip_tcp = 0;
  staty.inne = 0;
}

void printStats() {
    printf("Statystyki: \n");
    printf("\tArp:\t%d\n", staty.arp);
    printf("\tIP:\t%d\n", staty.ip);
    printf("\t\tUDP:\t%d\n", staty.ip_udp);
    printf("\t\tTCP:\t%d\n", staty.ip_tcp);
    printf("\tInne:\t%d\n", staty.inne);
}

void cleanup() {
  pcap_close(handle);
  free(errbuf);
}

void stop(int signo) {
    // print stats
  exit(EXIT_SUCCESS);
}

void trap(u_char *user, const struct pcap_pkthdr *h, const u_char *bytes) {
  struct ethhdr *ramka = (struct ethhdr*) bytes;
  int etherType = ntohs(ramka-> h_proto);

  if(ETH_P_ARP == etherType) {
    staty.arp++;
  } else if (ETH_P_IP == etherType ){
    staty.ip++;
    struct iphdr *ipRamka = (struct iphdr*) (sizeof(struct ethhdr)+ ramka);
    if(17 == ipRamka->protocol){
      staty.ip_udp++;
    } else if(6 == ipRamka->protocol){
      staty.ip_tcp++;
    }
    free(ipRamka);
  } else {
    staty.inne++;
  }
  free(ramka);
//   struct ethhdr = ((struct ethhdr*) bytes);
  // ETH_P_ARP
  // ETH_P_IP
  printf("[%dB of %dB]\n", h->caplen, h->len);
}

int main(int argc, char** argv) {
  atexit(cleanup);
  signal(SIGINT, stop);
  errbuf = malloc(PCAP_ERRBUF_SIZE);
  handle = pcap_create(argv[1], errbuf);
  pcap_set_promisc(handle, 1);
  pcap_set_snaplen(handle, 65535);
  pcap_activate(handle);
  pcap_loop(handle, -1, trap, NULL);
}