There is a program called Ping Tunnel to send TCP traffic over ICMP. From the project home page:
Ptunnel is an application that allows you to reliably tunnel TCP connections to a remote host using ICMP echo request and reply packets, commonly known as ping requests and replies. At first glance, this might seem like a rather useless thing to do, but it can actually come in handy in some cases. The following example illustrates the main motivation in creating ptunnel:
Setting: You're on the go, and stumble across an open wireless network. The network gives you an IP address, but won't let you send TCP or UDP packets out to the rest of the internet, for instance to check your mail. What to do? By chance, you discover that the network will allow you to ping any computer on the rest of the internet. With ptunnel, you can utilize this feature to check your mail, or do other things that require TCP.
Absolutely fantastic -- it Just Works. Download ping tunnel here.
- 30 Handy Bash Shell Aliases For Linux / Unix / Mac OS X
- Top 30 Nmap Command Examples For Sys/Network Admins
- 25 PHP Security Best Practices For Sys Admins
- 20 Linux System Monitoring Tools Every SysAdmin Should Know
- 20 Linux Server Hardening Security Tips
- Linux: 20 Iptables Examples For New SysAdmins
- Top 20 OpenSSH Server Best Security Practices
- Top 20 Nginx WebServer Best Security Practices
- 20 Examples: Make Sure Unix / Linux Configuration Files Are Free From Syntax Errors
- 15 Greatest Open Source Terminal Applications Of 2012
- My 10 UNIX Command Line Mistakes
- Top 10 Open Source Web-Based Project Management Software
- Top 5 Email Client For Linux, Mac OS X, and Windows Users
- The Novice Guide To Buying A Linux Laptop
{ 1 comment… read it below or add one }
ptunnel is a very cool application. Interestingly, it’s not very effective when the administrator properly configures his firewall to use “stateful”/application inspection of ICMP traffic.
e.g. looking for egress echo requests before allowing only one response, and checking for icmp sequence numbers.
In any case, it’s lot’s of fun to prey on the unsuspecting. :-)