pcap - How to analyse packet infromation from a traffic dump file in C++? -

i write c console program due dump network traffic "pcap" library. want packet information (e.g. protocol-type, sender-ip, etc) binary file.

my code :

#include "stdafx.h" #include <pcap.h> #include <stdio.h> #include <stdlib.h> #include <errno.h> #ifndef win32 #include <sys/socket.h> #include <netinet/in.h> #else #include <winsock.h> #endif   #define line_len 16 void dispatcher_handler(u_char *, const struct pcap_pkthdr *, const u_char *);  int main(int argc, char **argv) {     pcap_t *fp;     char errbuf[pcap_errbuf_size];     char source[pcap_buf_size];      if(argc != 2){          printf("usage: %s filename", argv[0]);         return -1;     }      /* create source string according new winpcap syntax */     if(pcap_createsrcstr(source,         // variable keep source string         pcap_src_file,  // want open file         null,           // remote host         null,           // port on remote host         argv[1],        // name of file want open         errbuf          // error buffer         ) != 0)     {         fprintf(stderr, "\nerror creating source string\n");         return -1;     }      /* open capture file */     if((fp = pcap_open(source,         // name of device         65536,          // portion of packet capture         // 65536 guarantees whole packet captured on link layers         pcap_openflag_promiscuous,     // promiscuous mode         1000,              // read timeout         null,              // authentication on remote machine         errbuf         // error buffer         )) == null)     {         fprintf(stderr, "\nunable open file %s.\n", source);         return -1;     }      // read , dispatch packets until eof reached     pcap_loop(fp, 0, dispatcher_handler, null);      return 0; }  void dispatcher_handler(u_char *temp1,     const struct pcap_pkthdr *header, const u_char *pkt_data) {     u_int = 0;     /* print pkt timestamp , pkt len */     printf("%ld:%ld (%ld)\n", header->ts.tv_sec, header->ts.tv_usec, header->len);      /* print packet */     for(i = 1; (i < header->caplen + 1); i++)     {         printf("%.2x ", pkt_data[i - 1]);         if((i % line_len) == 0) printf("\n");     }      printf("\n\n"); } 

how can read traffic information (not hex codes) traffic file?

for inspecting traffic file, first need save in hexadecimal file structure :

 printf("%.2x ", pkt_data[i - 1]); 

after can analysis hexadecimal strings. work 100 percentage!