Broadcasts messages over the local network while masking the senders IP Address
Sections
1 - How to build
2 - Strategy
3 - Sources
4 - Screenshots
To build the application - cd to the src directory - type "make"
To run the application - cd to the src directory - Use the command "sudo ./P2P"
To run the application in verbose mode (To see sender info) - cd to the src directory - Use the command "sudo ./P2P -v"
To run the application in unhidden mode (This will stop masking your IP address) - cd to the src directory - Use the command "sudo ./P2P -uh"
There should be no warnings/errors as long as theres no missing dependencies.
Notes:
- Application requires the NCurses library (For UI) to be installed on the computer running the application
- verbose and unhidden flags can be combined E.g. "sudo ./P2P -uh -v"
- This was developed on OSX
- Application must be ran with sudo to allow for "broadcast" messages
- Application will only send messages to others on the local network
- Each message is limited to 60 characters
The strategy was to "spoof" the sender IP addresses on all of the packets sent, so they can't be traced. If another user looks at the senders IP of your message, then it will show up as "1.0.0.0"
Since there will be no legitimate return address, I didn't want any replies to the packet, so I decided to send the messages as UDP packets.
In order to alter the sender address I had to make changes to the IP header. This is why I chose to do it in C, so I had lower level access to the raw packet headers.
To not track who to send messages to (To keep it more anonymous) I set all messages to "broadcast" to all other users on the network. This way anyone running the application will be looking for messages broadcasted on port 8820, and pick them up with no idea who sent them. The limitation from this is that to keep it decentralized it will only send messages on the local network.
This application is only designed to hide the IP address, not the devices MAC address, this can still be hidden with a macchanger, or the application can be altered to also write the ethernet header.
Editting raw sockets: http://www.cs.binghamton.edu/~steflik/cs455/rawip.txt
Broadcasting over LAN in C: http://www.tack.ch/multicast/broadcast.shtml
