Tcpjunk is a general TCP protocols testing and hacking utility.

Main features:

• Supports IPv4/IPv6
• Automatically send/receive data according to predefined session setup
• Client/Server mode
• Supports SSL
• Dynamic data insertion and manipulation using tags
• Traffic generation
• GUI mode

News:

2.9.03

• Added Tamper tag.
• Added max segment option.
• Many updates to GUI.
• Bug fixes.

2.8.21

• Fixed issue with initial session timeout
• Added long options.
• Help and man page updated.

2.8.11

• 2.8 is out of beta
• Many more GUI updates and fixes
• Many other bug fixes

Screenshot (in GUI mode):

Requirements:

• Updated GNU/Linux based system
• GTK+ 2 Toolkit
• OpenSSL Toolkit
• GtkSourceView 2
• pkgconfig utility

History:

2.8.05 BETA

• Many GUI improvements
• Removed UDP support (for now)
• Bug fixes

2.8.01 BETA

• Added IPv6 support
• Added UDP Client support (UDP Server support in progress)
• Added character array tag
• Added option for reusing random source IP's for multiple sessions (-N)
• Manual page updated
• Many bug fixes

2.7.01

• Added daemon mode (-a)
• Fixed sequential files (-e) flaw in server mode
• Fixed version number

2.6.92

• Fixed crash when using -f/-e options with binary files
• Fixed memory leaks when using multiple sections
• Minor GUI changes

2.6.90

• Redesigned encode tag

2.6.87

• Added -e option, sequential files from current directory
• bug fixes

2.6.86

• Fixed crash in CLI (in some distributions).
• Added encode tag.

2.6.80

• Added multiple session tabs
• Undo functionality
• IP options -P and -R fixed (broken since 2.660)
• Added "last data" option to fuzz and count tags
• Many other fixes

2.672

• Fixed crash related to tags in binary session data
• Fixed count tag in server mode
• Added verbosity to random file option
• Fixed tag parsing order issue
• Other minor fixes

2.670 BETA

• Update: 2.670 still has some issues, flagged as beta (latest stable ver is 2.649).
• Bulletproofed tag system
• Added new 'counter' tag
• Added hexdump feature
• Misc bug fixes.

2.661 BETA

• Fixed bug in 'system' tag insertion
• Minor layout and highlight improvements

2.660 BETA

• Added manual page
• Added syntax highlighting
• Removed session file size limit
• Added source port option
• Improved tags functionality
• Many bug fixes

2.649

• Fixed crash in GUI/Verbose mode

2.648

• Added option to use random session files from current directory (-f)
• Added verbosity to CLI (-v) / GUI mode