The HTTP Garden is a collection of HTTP servers and proxies configured to be composable, along with scripts to interact with them in a way that makes finding vulnerabilities much much easier. For some cool demos of the vulnerabilities that you can find with the HTTP Garden, check out our ShmooCon 2024 talk.
We'd like to thank our friends at Galois, Trail of Bits, Narf Industries, and Dartmouth College for making this project possible.
This material is based upon work supported by the Defense Advanced Research Projects Agency (DARPA) under contract number HR0011-19-C-0076.
- The HTTP Garden runs on x86_64 Linux, and is untested on other platforms.
- The target servers are built and run in Docker containers, so you'll need Docker.
- You'll also need the following Python packages, which you can get from PyPI (i.e. with
pip
) or from your system package manager:
docker
- For interacting with Docker
pyyaml
- For parsing yaml
tqdm
- For progress bars
If you're installing Python packages with your system package manager, be aware that the package names may need to be prefixed with py3-
, python3-
, or python-
, depending on the system.
- I also highly recommend installing rlwrap from your package manager, because it makes the Garden repl a whole lot more fun.
- Build the base image:
docker build ./images/http-garden-soil -t http-garden-soil
This image contains some basic utilities, plus a forked AFL++ that facilitates collecting coverage from processes without killing them.
- Build some HTTP servers and proxies:
docker compose build gunicorn hyper nginx haproxy nginx_proxy
There are, of course, way more targets in the HTTP garden than the ones we just built. It's just that building them all takes a long time. Even building these few will take a few minutes!
- Start up some servers and proxies:
docker compose up gunicorn hyper nginx haproxy nginx_proxy
- Start the repl:
rlwrap python3 tools/repl.py
- Filter a basic GET request through HAProxy, then through an Nginx reverse proxy, then send the result to Gunicorn, Hyper, and Nginx origin servers, and display whether their interpretations match:
garden> payload 'GET / HTTP/1.1\r\nHost: whatever\r\n\r\n' # Set the payload
garden> transduce haproxy nginx_proxy # Run the payload through the reverse proxies
[1]: 'GET / HTTP/1.1\r\nHost: whatever\r\n\r\n'
⬇️ haproxy
[2]: 'GET / HTTP/1.1\r\nhost: whatever\r\n\r\n'
⬇️ nginx_proxy
[3]: 'GET / HTTP/1.1\r\nHost: echo\r\nConnection: close\r\n\r\n'
garden> servers gunicorn hyper nginx # Select the servers
garden> grid # Show their interpretations
g
u
n
i h n
c y g
o p i
r e n
n r x
+-----
gunicorn|✓ ✓ ✓
hyper | ✓ ✓
nginx | ✓
Seems like they all agree. Let's try a more interesting payload:
garden> payload 'POST / HTTP/1.1\r\nHost: a\r\nTransfer-Encoding: chunked\r\n\r\n0\n\r\n'
garden> grid
g
u
n
i h n
c y g
o p i
r e n
n r x
+-----
gunicorn|✓ ✓ X
hyper | ✓ X
nginx | ✓
There's a discrepancy! This is because Nginx supports \n
as a line ending in chunk lines, but Hyper and Gunicorn don't. Nginx is technically violating RFC 9112 here, but the impact is likely minimal.
The images
directory contains a subdirectory for each HTTP server and transducer in the Garden.
Each target gets its own Docker image.
All programs are built from source when possible.
So that we can easily build multiple versions of each target, all targets are paremetrized with a repository URL (APP_REPO
), branch name (APP_BRANCH
), and commit hash (APP_VERSION
).
The tools
directory contains the scripts that are used to interact with the servers. Inside it, you'll find
diagnose_anomalies.py
: A script for enumerating benign HTTP parsing quirks in the systems under test to be ignored during fuzzing,repl.py
: The primary user interface to the HTTP Garden,update.py
: A script that updates the commit hashes indocker-compose.yml
,- ...and a few more scripts that aren't user-facing.
Name | Runs locally? | Coverage Collected? |
---|---|---|
aiohttp | yes | yes |
apache_httpd | yes | yes |
apache_tomcat | yes | no |
cheroot | yes | yes |
cpp_httplib | yes | no |
cpython_stdlib | yes | no |
dart_stdlib | yes | no |
eclipse_grizzly | yes | no |
eclipse_jetty | yes | no |
fasthttp | yes | no |
go_stdlib | yes | no |
gunicorn | yes | yes |
h2o | yes | yes |
haproxy_fcgi | yes | no |
hyper | yes | no |
hypercorn | yes | yes |
ktor | yes | no |
libevent | yes | no |
libmicrohttpd | yes | no |
libsoup | yes | no |
lighttpd | yes | yes |
mongoose | yes | yes |
netty | yes | no |
nginx | yes | yes |
node_stdlib | yes | no |
openbsd_httpd | yes | no |
openlitespeed | yes | no |
openwrt_uhttpd | yes | yes |
php_stdlib | yes | no |
phusion_passenger | yes | no |
protocol_http1 | yes | no |
puma | yes | no |
servicetalk | yes | no |
tornado | yes | no |
twisted | yes | no |
undertow | yes | no |
uvicorn | yes | yes |
waitress | yes | yes |
webrick | yes | no |
yahns | yes | no |
iis | no | no |
Name | Runs locally? |
---|---|
apache_httpd_proxy | yes |
apache_traffic_server | yes |
busybox_httpd_proxy | yes |
go_stdlib_proxy | yes |
h2o_proxy | yes |
haproxy | yes |
haproxy_invalid | yes |
lighttpd_proxy | yes |
nginx_proxy | yes |
openlitespeed_proxy | yes |
pingora | yes |
pound | yes |
spring_cloud_gateway | yes |
squid | yes |
varnish | yes |
yahns_proxy | yes |
akamai | no |
awselb_classic | no |
awselb_application | no |
cloudflare | no |
google_classic | no |
google_global | no |
iis_proxy | no |
openbsd_relayd | no |
The following are explanations for a few notable omissions from the Garden:
| Name | Rationale |
| unicorn | Uses the same HTTP parser as yahns
. |
| SwiftNIO | Uses llhttp
for HTTP parsing, which is already covered by node_stdlib
. |
| Bun | Uses picohttpparser
for HTTP parsing, which is already covered by h2o
. |
| Deno | Uses hyper
for HTTP parsing, which is already in the Garden. |
| Daphne | Uses twisted
for HTTP parsing, which is already in the Garden. |
| pitchfork | Uses the same parser as yahns
. |
| nghttpx | Uses lhttp
for HTTP parsing, which is already covered by node_stdlib
. |
| CherryPy | Uses cheroot
for HTTP parsing, which is already in the Garden. |
| libhttpserver | Uses libmicrohttpd
for HTTP parsing, which is already in the Garden. |
| Werkzeug | Uses the CPython stdlib for HTTP parsing, which is already in the Garden.
| Caddy | Uses the Go stdlib for HTTP parsing, which is already in the Garden. |
| Tengine | Uses Nginx's HTTP parsing logic. |
| OpenResty | Uses Nginx's HTTP parsing logic. |
See TROPHIES.md for a complete list of bugs that the Garden has found.