h2fuzz - fuzzing mod_http2 in Apache httpd

This repository is a place of comfort and relaxation while you watch the fuzzing tests pass (and stumble) against Apache httpd and its HTTP/2 implementation.

It is usable, but still work in progress. Anyone is invited to participate.

Status

This repository, once configured, will build honggfuzz from a master clone, nghttp2 from the version listed in configure.ac and a checkout of the subversion trunk of Apache httpd.

The you may type

make fuzz

and the components are built, installed into the prefix you configured and the tests are run.

Install

There are some reprequisites your system needs before this all works smoothly, most of them documented on the honggfuzz project itself, so in case of trouble, have a look there:

• you need clang >= version 4.0 installed
• you need to usual automake and autoconf things
• you need to be able to clone from github (fair chance of that when you have this repository) and the subversion client (svn).

Then you run

> autoreconf -i
> ./configure --prefix=$PWD/gen/apache
> make

and it should build and install everything in gen/apache locally. (Caveat: the httpd config places its pid file in /tmp so that several honggfguzz setups can better work with each other.)

The configuration if httpd is minimal (for now), so there is no need to OpenSSL and other third party libs. A new c-lang is the major dependency.

Usage

The following make commands are available:

make fuzz       #run honggfuzz endlessly on the installed httpd
make clean      #remove compilation results in subdirs
make install    #default target, checks out sources, builds and 
                #installs them in $prefix
make update     #performs git pull/svn update on honggfuzz and httpd copies

ToDos

Some ideas around this fuzzing:

• h2fuzz uses some parts of the honggfuzz test files, but has copies of the httpd patch and httpd config file. Updates of these in honggfuzz are not effective in h2fuzz.
• make reconfigure would be nice to run all subdir ./configure again and prep a new build&install
• top ./configure should take arguments to influence CFLAGS. Other -fsanitize=xxx would be interesting
• make update in httpd should revert and re-apply patches
• would be nice of drop httpd patches just in a dir and have them applied for testing

Credits

Many thanks to Robert Święcki who tested h2 with honggfuzz for some time and let me know when things get interesting. I decided that I have to run the tests myself also, to better save my users from hickups, so I felt the need to a comfortable setup.

Münster, 29.06.2017

Stefan Eissing