C program to split pcap file

split pcap file wireshark
tcpdump split pcap by time
tcpdump split pcap by size
merge pcap files
open large pcap file wireshark
wireshark truncate pcap file
search multiple pcap files
pcap file size

Can anyone help me with the C programming for splitting a network packet capture file (.pcap file) into smaller sized files (of same type or other). Though utilities like editcap or T-shark are already available for the job, I would really like to understand the coding behind it.

You can open pcap file with pcap_open_offline and read individual packets with pcap_next.

C program to split pcap file, Splits big pcap files into smaller ones. seconds <s> : Split on time, new file after <s> seconds. packets <c> : Split on packet count, new file after <c> packets. SplitCap is a free (as in beer) open source pcap file splitter. SplitCap splits one big pcap file into multiple files based on TCP and UDP sessions, one pcap file per session. SplitCap can also be used to split a pcap file into one pcap file per host-pair instead of session.

Winpcap offers wide range of solution to this problem

After reading ...in Test Packet Capture solution

for ( j=0; j<ulen; j++, pChar++ )
            {
                printf( "%c", isprint( (unsigned char)*pChar ) ? *pChar : '.' );                        
            }


                for ( j=0; j<ulen; j++)
                {   
                            fprintf(fp1, "%s", pChar); 
                            //fprintf(fp1, "%s", strtok(pChar,"MIND_ID"));  
                            fsize1 = ftell(fp1);

                            if (fsize1 > 665600) // close after 1MB 
                            {  fclose(fp1); 
                               printf("\n The size of given file 1 is : %d \n", fsize1);   
                               break;
                            }   

                }

use this code to store first and then split the given file into any number you want.

SplitCap - A fast PCAP file splitter, You can use tcpdump itself with the -C, -r and -w options tcpdump -r old_file -w new_files -C 10. The "-C" option specifies the size of the file to split into. Eg: In the​  Use the following command to split the PCAP to multiple files (e.g. exportpcap*.pcap), each file would contain 100 packets (or other value). “C:\Program Files\Wireshark\editcap.exe” -c 100 c1.pcap exportpcap.pcap 5. Review the folder content by using Microsoft Explorer or ‘dir’ command.

for splitting a network packet capture file (.pcap file) use library pcap_file_generator

Samle reading pcap file:

PCAPFILE  * pfr = lpcap_open("./pcaplibtestfile.pcap");
  pcap_hdr_t   phdr;
  if( lpcap_read_header( pfr, &phdr ))
  {
    int rese_rec_read = 0 ;
    pcaprec_hdr_and_data_t  p_rec_data;
    do{   
       rese_rec_read = lpcap_read_frame_record( pfr , &p_rec_data);
    }while(rese_rec_read>0);

sample writing to file:

 PCAPFILE * pfl = lpcap_create("./pcaplibtestfile.pcap");
  for( i=0;i< PKTS_COUNT;i++ )
  {
    /* TODO:  fill data   memcpy(eda.data , YOUR_DATA_BUF,SIZE_YOUR_DATA_BUF  );
       eda.len = SIZE_YOUR_DATA_BUF;
    */
   lpcap_write_data( pfl , &eda , i, 0 );
  }
  lpcap_close_file( pfl );

how to split a pcap file into a set of smaller ones, Pcap-splitter allows you to split a . pcap files based on time. following command as described on the bellow instructions: C:\Program Files\Wireshark\​editcap. Run tcpdump -r <input_pcap> -w <output_pcap> -C <file_size>, where input_pcap is the name of the fie you want to split, output_pcap is the output, and <file_size> is the approximate size of the split files in megabytes. For example: tcpdump -r input_packet_capture.pcap -w output_packet_capture -C 25 will split the file into ~25mb chunks. 4.

Split pcap file, I need to find a way to split a large pcap file into separated pcap files. What I want to find is a Tcpflow or Tcptrace don't generate pcap file as their output. The output pcap file using “follow tcp stream” code in my c project. # split-pcap.py file-name [packet-count] # Where: # file-name is the name or path of the file to be processed. This script # only supports pcap files, not pcapng. The following commands can be # used to convert a pcapng file to pcap format # tcpdump -r file.pcapng -w new-file.pcap # or

Split pcap file into smaller pcap file (according to tcp flow , HOW TO: Split huge Wireshark/TCPDump pcap files into smaller files editcap -​c <num of packets in the pcap file> <input pcap file> <output pcap file> and capinfos programs installed as part of the Wireshark installation. I need to find a way to split a large pcap file into separated pcap files. What I want to find is a application like Splitcap but I need a application which runs on Linux. Tcpflow or Tcptrace don't generate pcap file as their output. The output pcap file should contains a tcp flow. If there's an application, please let me know.

305635, If you have a big file you can quite easily split it into smaller files,using editcap. The “-c” parameter tells editcap to cut bigfile.pcapng into smaller files of new protocol dissectors added to the code are enabled by default,  Follow these steps on a computer with installed Wireshark to split large packet capture file into several smaller files: Open the Wireshark installation directory. Default is: Read the following manual pages: Put the large traffic capture file into some folder (e.g., C:\capture\). Open

Comments
  • Thanks a lot Tomasz. Can you also give me some idea on how a .pcap file can be split into overlapping time series. Can I use editcap/T-Shark for that??