Wireleap relay

This documentation is imported from the wireleap/relay README.md. Find a typo? Something not clear? Edit on Github

Installation

The recommended installation procedure starts with the creation of a system user account specifically for the wireleap-relay.

useradd -rUm --home-dir /opt/wireleap-relay wireleap-relay

Next, download and verify the latest release. Alternatively, you can build from source.

su -l wireleap-relay

# download binary and hashfile for Linux
DIST="https://github.com/wireleap/relay/releases/latest/download"
curl -O $DIST/wireleap-relay_linux-amd64
curl -O $DIST/wireleap-relay_linux-amd64.hash

# cryptographically verify integrity of the hashfile
gpg --recv-keys 693C86E9DECA9D07D79FF9D22ECD72AD056012E1
gpg --list-keys --with-fingerprint builds@wireleap.com
gpg --verify wireleap-relay_linux-amd64.hash

# verify checksum hash
sha512sum -c wireleap-relay_linux-amd64.hash

# rename the binary and set executable flag
mv wireleap-relay_linux-amd64 wireleap-relay
chmod +x wireleap-relay

# generate certificates and a keypair specific for the relay
./wireleap-relay init

# create a configuration file (see the next section)
$EDITOR config.json

Once configured, proceed to the testing and/or production section.

Configuration

Relays are configured through the file config.json, which includes service contracts the relay supports along with a specific configuration per each contract as well as the daemon configuration. Currently supported variables:

KeyTypeComment
addressstringaddress to bind to (host:port)
archive_dirstringpath to archive submitted sharetokens (optional)
auto_submit_intervalstringinterval between sharetoken submission retries
contracts.Xstringservice contract endpoint url
contracts.X.addressstringwireleap://host:port[/uri]
contracts.X.rolestringfronting entropic backing
contracts.X.keystringuser:password format enrollment key if required
contracts.X.update_channelstringupdate channel (default: "default")
auto_upgradeboolautomatically upgrade this relay (default: true)
{
    "address": "0.0.0.0:13490",
    "archive_dir": "archive/sharetokens",
    "auto_submit_interval": "5m0s",
    "contracts": {
        "https://contract1.example.com": {
            "address": "wireleap://relay1.example.com:13490",
            "role": "backing",
            "key": "backing:secretkey"
        },
        "https://contract2.example.com": {
            "address": "wireleap://relay1.example.com:13490",
            "role": "entropic"
        }
    }
}

Note: A fronting relay generally requires a webserver proxying configuration.

Web server proxying

When the fronting relay daemon is behind a proxying web server that supports HTTP/2, such as Apache or Nginx, the web server can be configured to proxy connections to the daemon while simultaneously serving the regular website traffic.

Protocol encapsulation

A HTTP/2 connection is used as transport and the individual connections are streams inside it. The HTTP/2 connection is opaque and valid traffic for the webserver to proxy. Once the proxying webserver has performed the TLS and H/2 negotiation (settings frame, etc.) and bidirectional streaming data transfer is setup, the encapsulated traffic is seamlessly proxied to and from the relay daemon address.

Fronting relay configuration example

{
    "address": "127.0.0.1:13490",
    "archive_dir": "archive/sharetokens",
    "auto_submit_interval": "5m0s",
    "contracts": {
        "https://contract1.example.com": {
            "address": "wireleap://www.example.com:443/wireleap",
            "role": "fronting"
        }
    }
}

Apache configuration example

<IfModule ssl_module>
 <IfModule http2_module>
   Listen 443 https
   Protocols h2
   <VirtualHost *:443>
     ServerAdmin admin@example.com
     SSLCertificateFile /path/to/crt
     SSLCertificateKeyFile /path/to/key
     SSLEngine on
     SSLProxyEngine on
     SSLProxyCheckPeerName off
     DocumentRoot /var/www/html

     <Location "/wireleap">
       <IfModule mod_reqtimeout.c>
         RequestReadTimeout handshake=0 header=0 body=0
       </IfModule>
       ProxyPass "h2://127.0.0.1:13490"
       ProxyPassReverse "h2://127.0.0.1:13490"
     </Location>
   </VirtualHost>
 </IfModule>
</IfModule>

Nginx configuration example

server {
    listen 443 ssl http2;
    server_name www.example.com;
    ssl_certificate /path/to/fullchain.pem;
    ssl_certificate_key /path/to/privkey.pem;
    ssl_protocols TLSv1.3;

    location /wireleap {
        grpc_pass grpcs://127.0.0.1:13490;
        grpc_ssl_protocols TLSv1.3;
    }
}

Testing

Once configured, you can test that everything works by manually starting the daemon.

su -l wireleap-relay

# start the relay in the foreground (ctrl+c to stop)
./wireleap-relay start --fg

# or, in the background
./wireleap-relay start
./wireleap-relay status
cat wireleap-relay.log
./wireleap-relay stop

Production

Increase ulimit

The default ulimit -n value of 1024 on most systems would likely prove too low for running a production relay. Consider changing it to a higher value.

echo 'wireleap-relay soft nofile 65535' >> /etc/security/limits.conf
echo 'wireleap-relay hard nofile 65535' >> /etc/security/limits.conf

Daemon supervisor

To keep the relay process up and running at all times, the use of a process supervisor like systemd is recommended. The following is a suitable systemd unit file, which will watch the relay daemon process and restart it if it fails for any reason.

[Unit]
Description=Wireleap relay process
After=multi-user.target
StartLimitIntervalSec=200
StartLimitBurst=5

[Service]
Type=forking
User=wireleap-relay
Group=wireleap-relay
RootDirectory=/opt/wireleap-relay
ExecStartPre=-/wireleap-relay stop
ExecStart=/wireleap-relay start
ExecReload=/wireleap-relay reload
ExecStop=/wireleap-relay stop
Restart=on-failure
RestartSec=10
KillMode=process
BindReadOnlyPaths=/etc/ssl/certs/ca-certificates.crt /etc/resolv.conf
MountAPIVFS=on
ProtectProc=invisible
ProcSubset=pid
PrivateUsers=on
PrivateDevices=on

[Install]
WantedBy=multi-user.target
# create the systemd unit file and enable it
$EDITOR /etc/systemd/system/wireleap-relay.service
systemctl enable /etc/systemd/system/wireleap-relay.service

# start the service, check on its status
systemctl start wireleap-relay.service
systemctl status wireleap-relay.service

Settlement

A service contract defines the service parameters and facilitates disbursing funds provided by a customer to service providers in proportion to service provided based on proof of service.

The proof of service in question are the sharetokens accumulated by a relay when relaying user traffic.

Submitting sharetokens

Sharetokens are accumulated when relaying user traffic and automatically submitted to the contract upon servicekey expiration. If for some reason the submission fails, it will be retried based on the auto_submit_interval as defined in the relay configuration.

Note: Sharetokens need to be submitted to the contract during the submission window (from servicekey expiration plus settlement.submission_window) as defined by the service contract.

Checking status

Once sharetokens are submitted for settlement, their status can be queried with the balance command. When the settlement window closes and all verification checks are complete, the final calculation is performed. Based on the calculation, the relay’s balance will be credited, also shown per the balance command.

Note: the available balance shown is the integer part of the real, internally stored balance of the relay. This ensures that settlement always results in a fair assignment of relay shares. It may also lead to sub-one cent balance increases under certain conditions which will not affect the available balance immediately but increase the internally stored balance.

su -l wireleap-relay

# show available balance, sharetokens awaiting settlement window,
# and last withdrawal from all contracts
./wireleap-relay balance

Initiating a withdrawal request

A relay operator may issue a withdrawal request up to or equal to their available balance.

su -l wireleap-relay

# show available balance
./wireleap-relay balance \
    --contract https://contract1.example.com

# request withdrawal
./wireleap-relay withdraw \
    --contract https://contract1.example.com \
    --destination acct_1032D82eZvKYlo2C \
    --amount 150

Information regarding the --destination can be obtained by visiting the link as defined in contract’s payout.info.

curl -s https://contract1.example.com/info | jq -r '.payout.info'

Upgrade

The precompiled binary of wireleap-relay includes both automatic and manual upgrade functionality. Due to protocol versioning, it is highly recommended to keep relays up to date.

Automatic upgrades

When auto_upgrade is set to true or not present in the relay config.json, the relay will attempt automatic upgrades whenever it receives an update notification from the directory during heartbeat on the update channel specified in the enrollment config. If an upgrade fails, a best-effort rollback is performed and the affected version is skipped.

The relay update channels supported by the directory and the respective latest version is exposed via the directory’s /info endpoint.

{
    "auto_upgrade": true,
    "contracts": {
        "https://contract1.example.com": {
            "update_channel": "default"
        }
    }
}

Manual upgrades

The upgrade process is interactive so you will have the possibility to accept or decline based on the changelog for the new release version.

If the upgrade was successful, the old binary is not deleted but kept as wireleap-relay.prev for rollback purposes in case issues manifest post-upgrade.

If the upgrade was not successful, it is possible to skip the faulty version explicitly.

su -l wireleap-relay

# perform interactive upgrade
./wireleap-relay upgrade

# rollback if required
./wireleap-relay rollback

# skip upgrades to version 1.2.3
echo "1.2.3" > .skip-upgrade-version

Versioning

Releases are based on semantic versioning, and use the format MAJOR.MINOR.PATCH. While the MAJOR version is 0, MINOR version bumps are considered MAJOR bumps per the semver spec.

Git tags are used to specify the software version, which are manually assigned by tagging the relevant changelog entry. Only tagged versions are CI-built and released after all unit and integration tests have passed successfully.

Note: Locally built binaries will include a suffix in addition to the latest tagged version, consisting of the number of commits past the tag and the abbreviated hash of the HEAD commit.

Building

Note: If you would like to make changes to the source code, please following the contributing instructions instead.

Note: Custom built binaries do not support upgrade functionality.

Clone the repository

git clone https://github.com/wireleap/relay.git

Checkout the latest tagged version

For locally built binaries to match the latest stable wireleap version, you will need to check out the latest git tag prior to building as opposed to building from master.

cd relay
git pull --tags origin master
git checkout $(git describe `git rev-list --tags --max-count=1`)

Build the binary

It is recommended to build the binary using docker, as described below which uses the official golang docker image.

# for your host operating system
./contrib/docker/build-bin.sh build/

# for a specific target os (linux / darwin)
TARGET_OS=linux ./contrib/docker/build-bin.sh build/

# specify a cache for faster subsequent builds
mkdir -p build/.deps
DEPS_CACHE=build/.deps ./contrib/docker/build-bin.sh build/

If you prefer to use your host system instead of docker, you can do so with contrib/build-bin.sh provided you have the relevant dependencies installed.

Contributing

This flow is loosely based on the standard GitHub flow collaborative development model.

Collaboration between developers is facilitated via pull requests from topic branches towards the master branch, and pull request reviews are used to achieve consensus before merging the changes into the master branch.

A note about the master branch:

  • Anything in the master branch is deployable, builds successfully and is tested to work. The CI/CD system performs both integration and unit tests, but should be considered as only a filter to immediately highlight PRs which would break the master branch and therefore need to be either discarded or amended. Automated checks are no substitute for code review, so all PRs are manually reviewed prior to merge.

  • Direct commits to the master branch are prohibited, with the only exception being a core-dev pushing a signed git-tag signifying a release.

Fork, clone and setup upstream remote

The following instructions outline the recommended procedure for creating a fork of this repository in order to contribute changes.

Firstly, click the fork button at the top of the page. Once forked, clone your fork and set an upstream remote to keep track of changes.

git clone git@github.com:USERNAME/relay.git

cd relay
git remote add upstream git@github.com:wireleap/relay.git
git checkout master
git pull --tags upstream master
git config commit.gpgsign true

Create a feature branch and make your changes

Create a descriptively named topic branch based on the master branch. Please take care to only address one issue/bug/feature per pull request.

git checkout master
git pull --tags upstream master
git checkout -b DESCRIPTIVE_BRANCH_NAME

When making your changes, test and commit as you go. Try to make commits that capture an atomic change to the codebase. Source code should be documented where necessary and the rationale for changes included in commits should be clear.

If a commit resolves a known issue or relates to other commits or PRs, please refer to them.

Unit testing

The unit tests can either be run on your host or within docker using the official golang docker image.

# run unit tests on host
./contrib/run-tests.sh

# run unit tests in docker
./contrib/docker/run-tests.sh

# run unit tests in docker (specify cache for faster subsequent tests)
mkdir -p build/.deps
DEPS_CACHE=build/.deps ./contrib/docker/run-tests.sh

Rebase on master if needed

It can happen that as you were working on a feature, the state of the upstream/master branch has changed due to merging other pull requests. In this case, rebase your topic branch on top of the master branch. If needed, resolve merge conflicts.

git checkout master
git fetch upstream
git merge upstream/master
git rebase --interactive master DESCRIPTIVE_BRANCH_NAME

After every change to the git history of your topic branch, perform testing to avoid regressions.

Push changes and submit a pull request

When you think the topic branch is ready for merging, passes all tests, all changes are committed with appropriate commit messages, and your topic branch is based on the current state of the upstream/master branch, push them to the topic branch (not master) of your fork.

# push changes
git push origin DESCRIPTIVE_BRANCH_NAME

# if you have already pushed commits to a topic branch, and later
# performed a rebase on top of master, a force push will be required
git push --force origin DESCRIPTIVE_BRANCH_NAME

Once pushed, follow the link specified in the git push output. Give your changes a last-minute correctness check, and supply the high-level description of the changes.

Finally, click create pull request so the reviewers can review and approve the changes, or request modifications prior to performing the merge.

Review process and merge

The pull request may be approved or additional modifications might be requested by one of the reviewers. If modifications are requested, commit and push more changes to the same topic branch and they will be included in the original pull request until it is ultimately closed.

Branch protection rules are in place. They include:

  • Requiring all commits in PRs to be signed.
  • Requiring all integration and unit tests to complete successfully.
  • Requiring at least one approval from a core-dev.

If there is an issue with the proposed changes, modifications should be requested. For discussions on the rationale of certain choices in the code, GitHub comments in the respective files can be left for the author of the pull request to address.

Please note that every merged pull request is considered final and it is always better to hold off on merging a pull request than have to open another one correcting the changes from the first one. Additionally, it is also sometimes a good idea to create pull requests towards another PRs topic branch instead of master. This allows unifying multiple sets of changes from different developers within the scope of a single PR.

Merging changes that are not unanimously approved by all reviewers is not allowed unless special arrangements are in place (e.g. a reviewer is away and explicitly asked to not wait on them for merging changes).

Once the above is satisfied and all the reviewers have approved the changes, the last person who gives their approval and has merge permissions will close the pull request by merging it into the master branch. However, if the author of the pull request has merge permissions, they may perform the merge subject to the above.

License

The MIT License (MIT)