Squashed 'external/fizz/' content from commit 2af43927d1

git-subtree-dir: external/fizz
git-subtree-split: 2af43927d1de6375fdb239abcccd14058dbbe62c

.github/workflows/getdeps_linux.yml

+# This file was @generated by getdeps.py
+
+name: linux
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+
+jobs:
+  build:
+    runs-on: ubuntu-18.04
+    steps:
+    - uses: actions/checkout@v1
+    - name: Install system deps
+      run: sudo python3 build/fbcode_builder/getdeps.py --allow-system-packages install-system-deps --recursive fizz
+    - name: Fetch boost
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests boost
+    - name: Fetch ninja
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests ninja
+    - name: Fetch cmake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests cmake
+    - name: Fetch double-conversion
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests double-conversion
+    - name: Fetch fmt
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests fmt
+    - name: Fetch gflags
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests gflags
+    - name: Fetch glog
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests glog
+    - name: Fetch googletest
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests googletest
+    - name: Fetch libevent
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libevent
+    - name: Fetch snappy
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests snappy
+    - name: Fetch zstd
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests zstd
+    - name: Fetch folly
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests folly
+    - name: Fetch autoconf
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests autoconf
+    - name: Fetch automake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests automake
+    - name: Fetch libtool
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libtool
+    - name: Fetch libsodium
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libsodium
+    - name: Build boost
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests boost
+    - name: Build ninja
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests ninja
+    - name: Build cmake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests cmake
+    - name: Build double-conversion
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests double-conversion
+    - name: Build fmt
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests fmt
+    - name: Build gflags
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests gflags
+    - name: Build glog
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests glog
+    - name: Build googletest
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests googletest
+    - name: Build libevent
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libevent
+    - name: Build snappy
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests snappy
+    - name: Build zstd
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests zstd
+    - name: Build folly
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests folly
+    - name: Build autoconf
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests autoconf
+    - name: Build automake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests automake
+    - name: Build libtool
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libtool
+    - name: Build libsodium
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libsodium
+    - name: Build fizz
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --src-dir=. fizz  --project-install-prefix fizz:/usr/local
+    - name: Copy artifacts
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fixup-dyn-deps --strip --src-dir=. fizz _artifacts/linux  --project-install-prefix fizz:/usr/local --final-install-prefix /usr/local
+    - uses: actions/upload-artifact@master
+      with:
+        name: fizz
+        path: _artifacts
+    - name: Test fizz
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages test --src-dir=. fizz  --project-install-prefix fizz:/usr/local

.github/workflows/getdeps_mac.yml

+# This file was @generated by getdeps.py
+
+name: mac
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+
+jobs:
+  build:
+    runs-on: macOS-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: Install system deps
+      run: sudo python3 build/fbcode_builder/getdeps.py --allow-system-packages install-system-deps --recursive fizz
+    - name: Fetch boost
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests boost
+    - name: Fetch openssl
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests openssl
+    - name: Fetch ninja
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests ninja
+    - name: Fetch cmake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests cmake
+    - name: Fetch double-conversion
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests double-conversion
+    - name: Fetch fmt
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests fmt
+    - name: Fetch gflags
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests gflags
+    - name: Fetch glog
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests glog
+    - name: Fetch googletest
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests googletest
+    - name: Fetch libevent
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libevent
+    - name: Fetch snappy
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests snappy
+    - name: Fetch zstd
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests zstd
+    - name: Fetch folly
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests folly
+    - name: Fetch autoconf
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests autoconf
+    - name: Fetch automake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests automake
+    - name: Fetch libtool
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libtool
+    - name: Fetch libsodium
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libsodium
+    - name: Build boost
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests boost
+    - name: Build openssl
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests openssl
+    - name: Build ninja
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests ninja
+    - name: Build cmake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests cmake
+    - name: Build double-conversion
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests double-conversion
+    - name: Build fmt
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests fmt
+    - name: Build gflags
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests gflags
+    - name: Build glog
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests glog
+    - name: Build googletest
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests googletest
+    - name: Build libevent
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libevent
+    - name: Build snappy
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests snappy
+    - name: Build zstd
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests zstd
+    - name: Build folly
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests folly
+    - name: Build autoconf
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests autoconf
+    - name: Build automake
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests automake
+    - name: Build libtool
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libtool
+    - name: Build libsodium
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libsodium
+    - name: Build fizz
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --src-dir=. fizz  --project-install-prefix fizz:/usr/local
+    - name: Copy artifacts
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fixup-dyn-deps --src-dir=. fizz _artifacts/mac  --project-install-prefix fizz:/usr/local --final-install-prefix /usr/local
+    - uses: actions/upload-artifact@master
+      with:
+        name: fizz
+        path: _artifacts
+    - name: Test fizz
+      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages test --src-dir=. fizz  --project-install-prefix fizz:/usr/local

.github/workflows/getdeps_windows.yml

+# This file was @generated by getdeps.py
+
+name: windows
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+
+jobs:
+  build:
+    runs-on: windows-2016
+    steps:
+    - uses: actions/checkout@v1
+    - name: Export boost environment
+      run: "echo ::set-env name=BOOST_ROOT::%BOOST_ROOT_1_69_0%"
+      shell: cmd
+    - name: Fix Git config
+      run: git config --system core.longpaths true
+    - name: Fetch libsodium
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libsodium
+    - name: Fetch boost
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests boost
+    - name: Fetch ninja
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests ninja
+    - name: Fetch cmake
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests cmake
+    - name: Fetch double-conversion
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests double-conversion
+    - name: Fetch fmt
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests fmt
+    - name: Fetch gflags
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests gflags
+    - name: Fetch glog
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests glog
+    - name: Fetch googletest
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests googletest
+    - name: Fetch perl
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests perl
+    - name: Fetch openssl
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests openssl
+    - name: Fetch snappy
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests snappy
+    - name: Fetch zlib
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests zlib
+    - name: Fetch zstd
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests zstd
+    - name: Fetch libevent
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests libevent
+    - name: Fetch folly
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests folly
+    - name: Build libsodium
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libsodium
+    - name: Build boost
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests boost
+    - name: Build ninja
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests ninja
+    - name: Build cmake
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests cmake
+    - name: Build double-conversion
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests double-conversion
+    - name: Build fmt
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests fmt
+    - name: Build gflags
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests gflags
+    - name: Build glog
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests glog
+    - name: Build googletest
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests googletest
+    - name: Build perl
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests perl
+    - name: Build openssl
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests openssl
+    - name: Build snappy
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests snappy
+    - name: Build zlib
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests zlib
+    - name: Build zstd
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests zstd
+    - name: Build libevent
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests libevent
+    - name: Build folly
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests folly
+    - name: Build fizz
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages build --src-dir=. fizz 
+    - name: Copy artifacts
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages fixup-dyn-deps --src-dir=. fizz _artifacts/windows  --final-install-prefix /usr/local
+    - uses: actions/upload-artifact@master
+      with:
+        name: fizz
+        path: _artifacts
+    - name: Test fizz
+      run: python build/fbcode_builder/getdeps.py --allow-system-packages test --src-dir=. fizz 

.gitignore

+out/

.travis.yml

+# Facebook projects that use `fbcode_builder` for continuous integration
+# share this Travis configuration to run builds via Docker.
+
+# Docker disables IPv6 in containers by default. Enable it for unit tests that need [::1].
+before_script:
+  - if [[ "$TRAVIS_OS_NAME" != "osx" ]];
+    then
+      sudo build/fbcode_builder/docker_enable_ipv6.sh;
+    fi
+
+env:
+  global:
+    - travis_cache_dir=$HOME/travis_ccache
+    # Travis times out after 50 minutes. Very generously leave 10 minutes
+    # for setup (e.g.  cache download, compression, and upload), so we never
+    # fail to cache the progress we made.
+    - docker_build_timeout=40m
+
+cache:
+  # Our build caches can be 200-300MB, so increase the timeout to 7 minutes
+  # to make sure we never fail to cache the progress we made.
+  timeout: 420
+  directories:
+  - $HOME/travis_ccache  # see docker_build_with_ccache.sh
+
+# Ugh, `services:` must be in the matrix, or we get `docker: command not found`
+#   https://github.com/travis-ci/travis-ci/issues/5142
+matrix:
+  include:
+    - env: ['os_image=ubuntu:18.04', gcc_version=7]
+      services: [docker]
+
+addons:
+  apt:
+    packages: python2.7
+
+script:
+  # We don't want to write the script inline because of Travis kludginess --
+  # it looks like it escapes " and \ in scripts when using `matrix:`.
+  - ./build/fbcode_builder/travis_docker_build.sh

CODE_OF_CONDUCT.md

+# Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to make participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies within all project spaces, and it also applies when
+an individual is representing the project or its community in public spaces.
+Examples of representing a project or community include using an official
+project e-mail address, posting via an official social media account, or acting
+as an appointed representative at an online or offline event. Representation of
+a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at <opensource-conduct@fb.com>. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq
+

CONTRIBUTING.md

+# Contributing to Fizz
+We want to make contributing to this project as easy and transparent as
+possible.
+
+## Code of Conduct
+The code of conduct is described in [`CODE_OF_CONDUCT.md`](CODE_OF_CONDUCT.md).
+
+## Pull Requests
+We actively welcome your pull requests.
+
+1. Fork the repo and create your branch from `master`.
+2. If you've added code that should be tested, add tests.
+3. If you've changed APIs, update the documentation.
+4. Ensure the test suite passes.
+5. If you haven't already, complete the Contributor License Agreement ("CLA").
+
+## Contributor License Agreement ("CLA")
+In order to accept your pull request, we need you to submit a CLA. You only need
+to do this once to work on any of Facebook's open source projects.
+
+Complete your CLA here: <https://code.facebook.com/cla>
+
+## Issues
+We use GitHub issues to track public bugs. Please ensure your description is
+clear and has sufficient instructions to be able to reproduce the issue.
+
+Facebook has a [bounty program](https://www.facebook.com/whitehat/) for the safe
+disclosure of security bugs. In those cases, please go through the process
+outlined on that page and do not file a public issue.
+
+## License
+By contributing to Fizz, you agree that your contributions will be licensed
+under the LICENSE file in the root directory of this source tree.

LICENSE

+BSD License
+
+Copyright (c) 2018-present, Facebook, Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+ * Neither the name Facebook nor the names of its contributors may be used to
+   endorse or promote products derived from this software without specific
+   prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

README.md

+<p align="center">
+  <img width="500" height="216" alt="Fizz" src="logo2x.png">
+</p>
+
+[![Travis Build Status](https://api.travis-ci.org/facebookincubator/fizz.svg?branch=master)](https://travis-ci.org/facebookincubator/fizz)
+[![CI Status](https://github.com/facebookincubator/fizz/workflows/CI/badge.svg?branch=master)](https://github.com/facebookincubator/fizz/actions?workflow=CI)
+
+Fizz is a TLS 1.3 implementation.
+
+Fizz currently supports TLS 1.3 drafts 28, 26 (both wire-compatible with the
+final specification), and 23. All major handshake modes are supported, including
+PSK resumption, early data, client authentication, and HelloRetryRequest.
+
+More background and details are available on the
+[Facebook Code Blog](https://code.fb.com/networking-traffic/deploying-tls-1-3-at-scale-with-fizz-a-performant-open-source-tls-library/).
+
+## Dependencies
+
+Fizz largely depends on three libraries: [folly](https://www.github.com/facebook/folly),
+[OpenSSL](https://www.openssl.org/), and [libsodium](https://github.com/jedisct1/libsodium).
+
+## Source Layout
+- `fizz/crypto`:   Cryptographic primitive implementations (most are wrapping
+                   OpenSSL or libsodium)
+- `fizz/record`:   TLS 1.3 record layer parsing
+- `fizz/protocol`: Common protocol code shared between client and server
+- `fizz/client`:   Client protocol implementation
+- `fizz/server`:   Server protocol implementation
+- `fizz/tool`:     Example CLI app source
+
+## Design
+
+The core protocol implementations are in `ClientProtocol` and `ServerProtocol`.
+`FizzClientContext` and `FizzServerContext` provide configuration options.
+`FizzClient` and `FizzServer` (which both inherit from `FizzBase`) provide
+applications with an interface to interact with the state machine.
+`FizzClient`/`FizzServer` receives events from the application layer, invokes the
+correct event handler, and invokes the application `ActionVisitor` to process the
+actions.
+
+`AsyncFizzClient` and `AsyncFizzServer` provide implementations of the folly
+`AsyncTransportWrapper` interface. They own an underlying transport (for example
+`AsyncSocket`) and perform the TLS handshake and encrypt/decrypt application
+data.
+
+## Features
+
+Fizz has several important features needed from a modern TLS library.
+
+### Performance
+
+Fizz supports scatter/gather IO by default via folly's IOBufs, and will encrypt
+data in-place whenever possible, saving memcpys. Due to this and several
+other optimizations, we found in our load balancer benchmarks that Fizz has 10%
+higher throughput than our prior SSL library which uses folly's
+[AsyncSSLSocket](https://github.com/facebook/folly/blob/master/folly/io/async/AsyncSSLSocket.h).
+Fizz also consumes less memory per connection than AsyncSSLSocket.
+
+### Async by default
+
+Fizz has asynchronous APIs to be able to offload functions like certificate
+signing and ticket decryption. The API is based on folly's
+[Futures](https://github.com/facebook/folly/tree/master/folly/futures) for painless
+async programming.
+
+### TLS features
+
+Fizz supports APIs like exported keying material as well as zero-copy APIs
+needed to use TLS in other protocols like QUIC.
+
+### Secure design abstractions
+
+Fizz is built on a custom state machine which uses the power of the C++ type system
+to treat states and actions as types of their own. As the code changes, this allows us
+to catch invalid state transitions as compilation errors instead of runtime errors and
+helps us move fast.
+
+## Sample Applications
+
+Fizz includes an example program that showcases the basic client/server functionality
+supported by Fizz. The binary is called `fizz` and it has similar usage to the
+`openssl` or `bssl` commands.
+
+For example, to start a TLS server on port 443 with a specified cert:
+```
+fizz server -accept 443 -cert foo.pem -key foo.key
+```
+
+Then, on the same host, you can connect with:
+
+```
+fizz client -connect localhost:443
+```
+
+Both ends will echo whatever data they receive and send any terminal input to the
+peer. Hitting CTRL+D on either end will terminate the connection.
+
+The source code for this program can be found under `fizz/tool`.
+
+## Building
+
+### Ubuntu 16.04 LTS
+
+To begin, you should install the dependencies we need for build. This largely
+consists of [folly](https://github.com/facebook/folly)'s dependencies, as well as
+[libsodium](https://github.com/jedisct1/libsodium).
+
+```
+sudo apt-get install \
+    g++ \
+    cmake \
+    libboost-all-dev \
+    libevent-dev \
+    libdouble-conversion-dev \
+    libgoogle-glog-dev \
+    libgflags-dev \
+    libiberty-dev \
+    liblz4-dev \
+    liblzma-dev \
+    libsnappy-dev \
+    make \
+    zlib1g-dev \
+    binutils-dev \
+    libjemalloc-dev \
+    libssl-dev \
+    pkg-config \
+    libsodium-dev
+```
+
+Then, build and install folly:
+
+```
+git clone https://github.com/facebook/folly
+mkdir folly/build_ && cd folly/build_
+cmake ..
+make -j $(nproc)
+sudo make install
+```
+
+And lastly, build and install fizz.
+
+```
+cd ../..
+git clone https://github.com/facebookincubator/fizz
+mkdir fizz/build_ && cd fizz/build_
+cmake ../fizz
+make -j $(nproc)
+sudo make install
+```
+
+### Building on Mac