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            A package for capturing and analyzing network
         flow data and intraflow data, for network research, 
              forensics, and security monitoring. 

Overview

   Joy is a BSD-licensed libpcap-based software package for extracting
   data features from live network traffic or packet capture (pcap)
   files, using a flow-oriented model similar to that of IPFIX or
   Netflow, and then representing these data features in JSON.  It
   also contains analysis tools that can be applied to these data
   files.  Joy can be used to explore data at scale, especially
   security and threat-relevant data.

   JSON is used in order to make the output easily consumable by data
   analysis tools.  While the JSON output files are somewhat verbose,
   they are reasonably small, and they respond well to compression.
   
   Joy can be configured to obtain intraflow data, that is, data and
   information about events that occur within a network flow,
   including:

      * the sequence of lengths and arrival times of IP packets,
        up to some configurable number of packets,

      * the empirical probability distribution of the bytes within the
        data portion of a flow, and the entropy derived from that
        value, 
   
      * the sequence of lengths and arrival times of TLS records, 

      * other non-encrypted TLS data, such as the list of offered
        ciphersuites, the selected ciphersuite, and the length of the
        clientKeyExchange field,

      * the name of the process associated with the flow, for flows
        originate or terminate on the host on which pcap is running.

   Joy is intended for use in security research, forensics, and for
   the monitoring of (small scale) networks to detect vulnerabilities,
   threats and other unauthorized or unwanted behavior.  Researchers,
   administrators, penetration testers, and security operations teams
   can put this information to good use, for the protection of the
   networks being monitored, and in the case of vulnerabilities, for
   the benefit of the broader community through improved defensive
   posture.  As with any network monitoring tool, Joy could
   potentially be misused; do not use it on any network of which you
   are not the owner or the administrator.  

   Flow, in positive psychology, is a state in which a person
   performing an activity is fully immersed in a feeling of energized
   focus, deep involvement, and joy.  This second meaning inspired
   the choice of name for this software package.
   
   Joy is alpha/beta software; we hope that you use it and benefit
   from it, but do understand that it is not suitable for production
   use.


Credits

   This package was written by David McGrew and Blake Anderson
   {mcgrew,blaander}@cisco.com of Cisco Systems Advanced Security
   Research Group (ASRG).

Quick Start

Building

   Joy has been successfully run and tested on Linux (Debian, Ubuntu,
   and CentOS) and Mac OSX.  The system has been built with gcc and
   GNU make, but it should work with other development environments as
   well.

   First, obtain the package from github, and change to the joy
   directory.

   To build the package, run "make" in the main directoroy:

      [joy]$ make 

   This will cause the programs to be compiled, linked, stripped, and
   copied into the main directory as appropriate.  It will also run a
   test script and a unit test program.

   The main program for extracting data features from pcap files or
   live packet captures is the program pcap2flow, which occupies the
   src/ subdirectory.  It is copied into the main joy directory after
   a successful build.  It can be run from that directory, or
   installed so that it will automatically run as a daemon on Linux or
   Mac OSX.  

Running and Configuration

   To understand how pcap2flow is configured, read one of the
   configuration files (linux.cfg or macosx.cfg).  To process a pcap
   file in offline mode, run

      [joy]$ ./pcap2flow [ OPTIONS ] filename [ filename2 ... ]

   For instance, 
   
      [joy]$ ./pcap2flow bidir=1 output=data.json filename

   To run the packet capture in online mode, use the same command
   form, but have OPTIONS include an interface=<value> command, and
   omit the filename(s) from the command line.  For instance,

      [joy]$ sudo ./pcap2flow interface=eth0 bidir=1 output=data.json

   There are many command line options, so instead of typing them all
   onto the command line, you may want to have the program read a
   configuration file.  Two such files come with the distribution,
   linux.cfg and macosx.cfg.  If you want to change the program
   defaults (and you probably do, in order to capture exactly the data
   of interest to you), then make a copy of the configuration file.
   By making a local copy that has a different name, your
   configuration will not be clobbered if you update the joy package.


Analytics

   Please see the file saltUI/README.


Installation

   NOTE: THE DEFAULT CONFIGURATION USED BY THE INSTALL SCRIPT WILL
   PERFORM ONGOING DATA CAPTURE, WHICH WILL RESTART UPON REBOOT.  If
   you do not want an ongoing capture, we suggest that you do not use
   the install script.

   To install the package on your system, you will need to first build
   it.  Run the script install-sh (as root, or using sudo) to install
   the package.  

      [joy]$ sudo ./install-sh

   If you run the script with no arguments, then the default
   configuration will be installed into the /etc/ directory.  To have
   a different configuration file installed, then use the -c option to
   the install script:

      [joy]$ sudo ./install-sh -c local-config-file.cfg

   You can also configure anonymization of addresses, which requires a
   file containing the internal subnets.  The default file for those
   subnets is internal.net; you can change the configuration with the
   -a option.  Similarly, you can change the watchfile of IP addresses
   (using the -w option) or the SSH private key used to have files
   uploaded via scp (using the -k option).  To see the full option
   description for the installer, run that program with the -h option
   to see the help or "usage" message.


Documentation

   A man page will be built and installed automatically as part of the
   package.  See the file pcap2flow.1, or after the install-sh script
   has been run, access the man page through "man pcap2flow".


Testing

   Run the script ./pcap2flow_test.sh and the utility src/unit_test to
   test the programs.  These programs will indicate success or failure
   on the command line.