Gspoof

Gspoof is a powerful software tool for building and sending accurate TCP packets, with or without data payloads. Built on the GTK+ platform, Gspoof's advanced features enable the modification of TCP/IP and Ethernet headers to operate at the Link Level. With two different modes available, users can adjust IP and TCP headers, as well as Ethernet headers with the standard mode.

In the standard mode, users can easily adjust the following IP and TCP header fields:

- Source IP address (autodetects from available interface, if possible)
- Destination IP address
- TTL time to live (default value is 64)
- ID (16 byte random generate value)
- TOS type of service (automatically calculated from ECN parameters)
- Source port
- Destination port
- Control flags (multiple flags can be specified together)
- Sequence number (32 byte random generate value)
- Acknowledgement number (32 byte random generate value)
- Window size (default value is 32767)
- Urgent pointer (16 byte random generate value)

Gspoof's latest release includes the addition of Explicit Congestion Notification support, as well as bug fixes in ltostr() and console.c. The code has also been cleaned up, and tips have been fixed.

Overall, Gspoof is a reliable and versatile tool for experienced software developers looking for a solution to build and send TCP packets with ease.