So, my project for Fedora Infrastructure (fedmsg) connects around with zeromq. Way back in the Spring of this year, skvidal suggested that I "fuzz" it and see what happens, "fuzz" meaning try to cram random bits down its tubes.
I have a little pair of python scripts that I carry around in my ~/scratch/ dir to debug various zeromq situations. One of the scripts is topics_pub.py; it binds to an endpoint and publishes messages on topics. The other is topics_sub.py which connects to an endpoint and prints messages it receives to stdout.
To fuzz the subscriber, I had it connect to a garbage source built with /dev/random and netcat. In one terminal, I ran:
$ cat /dev/random | nc -l 3005
and in the other, I ran:
$ python topics_sub.py "tcp://*:3005"
... and nothing happened.
To fuzz the publisher, I hooked /dev/random up to telnet:
$ python topics_pub.py "tcp://127.0.0.1:3005" $ cat /dev/random | telnet 127.0.0.1 3005
... and it didn't fall over. Encouraging.