psiphon-labs / tls-tris

crypto/tls, now with 100% more 1.3. THE API IS NOT STABLE AND DOCUMENTATION IS NOT GUARANTEED.

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crypto/tls, now with 100% more 1.3.

THE API IS NOT STABLE AND DOCUMENTATION IS NOT GUARANTEED.

Usage

Since crypto/tls is very deeply (and not that elegantly) coupled with the Go stdlib, tls-tris shouldn't be used as an external package. It is also impossible to vendor it as crypto/tls because stdlib packages would import the standard one and mismatch.

So, to build with tls-tris, you need to use a custom GOROOT.

A script is provided that will take care of it for you: ./_dev/go.sh. Just use that instead of the go tool.

The script also transparently fetches the custom Cloudflare Go 1.10 compiler with the required backports.

Development

Dependencies

Copy paste line bellow to install all required dependencies:

• ArchLinux:

pacman -S go docker gcc git make patch python2 python-docker rsync

• Debian:

apt-get install build-essential docker go patch python python-pip rsync
pip install setuptools
pip install docker

• Ubuntu (18.04) :

apt-get update
apt-get install build-essential docker docker.io golang patch python python-pip rsync sudo
pip install setuptools
pip install docker
sudo usermod -a -G docker $USER

Similar dependencies can be found on any UNIX based system/distribution.

Building

There are number of things that need to be setup before running tests. Most important step is to copy go env GOROOT directory to _dev and swap TLS implementation and recompile GO. Then for testing we use go implementation from _dev/GOROOT.

git clone https://github.com/cloudflare/tls-tris.git
cd tls-tris; cp _dev/utils/pre-commit .git/hooks/ 
make -f _dev/Makefile build-all

Testing

We run 3 kinds of test:.

• Unit testing:
  make -f _dev/Makefile test-unit
• Testing against BoringSSL test suite:
  make -f _dev/Makefile test-bogo
• Compatibility testing (see below):
  make -f _dev/Makefile test-interop

To run all the tests in one go use:

make -f _dev/Makefile test

Testing interoperability with 3rd party libraries

In order to ensure compatibility we are testing our implementation against BoringSSL, NSS and PicoTLS.

Makefile has a specific target for testing interoperability with external libraries. Following command can be used in order to run such test:

make -f _dev/Makefile test-interop

The makefile target is just a wrapper and it executes _dev/interop_test_runner script written in python. The script implements interoperability tests using python unittest framework.

Script can be started from command line directly. For example:

> ./interop_test_runner -v InteropServer_NSS.test_zero_rtt
test_zero_rtt (__main__.InteropServer_NSS) ... ok

----------------------------------------------------------------------
Ran 1 test in 8.765s

OK

Debugging

When the environment variable TLSDEBUG is set to error, Tris will print a hexdump of the Client Hello and a stack trace if an handshake error occurs. If the value is short, only the error and the first meaningful stack frame are printed.