README for the Network Rerouter Daemon
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COMPILING
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1. Make configuration changes.
For most systems, no changes need to be made. However, the following
configuration options exist:
- the fexecve() library call doesn't work properly on all Linux kernels prior
to 2.6.22-rc1, and possibly later ones as well. To enable a work-around,
add the string "-DBROKEN_FEXECVE" to the CXXFLAGS variable in the makefile.
- the NF_STOP packet verdict doesn't exist in Linux kernels prior to 2.6.12.
To enable a work-around, add the string "-DNO_NF_STOP" to the CXXFLAGS
variable in the makefile.
- the variables NERD_SERVER_ROOT, NERD_PIPE_FD, NERD_SERVER_TIMEOUT and
NERD_CONNECTION_TIMEOUT in nerd.h can be modified if desired. See nerd.h
for details.
2. Build the program.
$ make
To build with debugging options enabled, use
$ make debug
3. (Optional) Build the program documentation.
$ make doc
4. Install the program.
$ make install
To install start-up files appropriate for Red Hat-derived systems, use
$ make install-rh
RUNNING
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Before the Network Rerouter Daemon will run, there need to be rules in the
OUTPUT chain of iptables' "mangle" table to redirect all packets destined to
simulated subnets and all responses from them to the iptables QUEUE target.
Also, the "ip_queue" module must be loaded. This can be accomplished using
commands similar to the following (where 123.123.123.0/24 is a network to
simulate):
$ iptables -t mangle -A OUTPUT -p tcp -d 123.123.123.0/24 -j QUEUE
$ iptables -t mangle -A OUTPUT -p tcp -d 127.0.0.1 --dport 1 -j QUEUE
$ modprobe ip_queue
As many networks as desired can be simulated; simply add more iptables rules
similar to the first.
On Red Hat-derived systems, the start-up files installed by "make install-rh"
will automatically create rules for all networks listed in the "NETWORKS"
variable in /etc/sysconfig/nerd.conf.
rdegraaf/NeRD
The Network Rerouting Daemon is a program that I wrote in 2007, with design advice from Dr. John Aycock, to support his "Spamulator" project (https://dl.acm.org/citation.cfm?id=1384311). It was written for a Linux platform that was somewhat dated at the time and probably won't build cleanly on a modern platform.
C++