See the overview of the project at https://attestation.app/about.
Installation guide
This is a generic guide on setting up the attestation server.
You need to set up nginx using the nginx configuration in the nginx directory in this repository. You'll need to adjust it based on your domain name. The sample configuration relies on certbot, nginx-rotate-session-ticket-keys, and certbot-ocsp-fetcher. Setting up the web server is out-of-scope for this guide.
Install a headless Java 18 runtime environment. The package name on Debian-based distributions is
openjdk-18-jre-headless or jre-openjdk-headless on Arch Linux. Install sqlite3 in order to set up the email configuration for the
database.
As root, on the server:
useradd -m -s /bin/bash -b /var/lib attestation
mkdir -p /opt/attestation/deploy_{a,b}
ln -s /opt/attestation/deploy_a /opt/attestation/deploy
mkdir -p /srv/attestation.app_{a,b}
ln -s /srv/attestation.app_a /srv/attestation.app
Set up ssh authorized_keys for the attestation user.
Copy attestation.service to /etc/systemd/system/attestation.service.
On your development machine, you will need to change the remote variable in the scripts to your server. Then deploy the attestation server and static content:
./deploy-server
./deploy-static
As root on the server, enable and start the attestation server:
systemctl enable attestation
systemctl start attestation
The server will be listening on [::1]:8080 by default which can be changed.
Email alert configuration
In order to send email alerts, AttestationServer needs to be configured with valid credentials for
an SMTP server. The configuration is stored in the Configuration table in the database and can
be safely modified while the server is running to have it kick in for the next email alert cycle.
Only SMTPS (SMTP over TLS) with a valid certificate is supported for remote email servers. STARTTLS is deliberately not supported because it's less secure unless encrypted is enforced, in which case it makes more sense to use SMTPS anyway. The username must also be the full address for sending emails.
For example, making an initial configuration:
sqlite3 attestation.db "INSERT INTO Configuration VALUES ('emailUsername', '[email protected]'), ('emailPassword', '<password>'), ('emailHost', 'mail.grapheneos.org'), ('emailPort', '465')"
The attestation.service unit only allows the service to communicate over localhost by default
so the IPAddressDeny/IPAddressAllow configuration either needs to be removed or extended to
include your DNS server and mail server IP addresses when using a remote mail server.
Handling abuse
The emailBlacklistPatterns array in
src/main/java/app/attestation/server/AttestationServer.java can be used to blacklist email
addresses using regular expressions. We plan to move this to a table in the database so that it
can be configured dynamically without modifying the sources, rebuilding and redeploying. For now,
this was added to quickly provide a way to counter abuse.
API for the Auditor app
QR code
The scanned QR code contains space-separated values in plain-text: <domain> <userId> <subscribeKey> <verifyInterval>. The subscribeKey should be treated as an opaque string rather
than assuming base64 encoding. Additional fields may be added in the future.
/challenge
- Request method: POST
- Request headers: n/a
- Request body: n/a
- Response body:
Returns a standard challenge message in the same format as the Auditor app QR code. The challenge can only be used once and expires in 1 minute.
The server challenge index is always zeroed out and the userId should be used instead.
/verify
- Request method: POST
- Request headers:
The Authorization header needs to be set to Auditor <userId> <subscribeKey> for an unpaired
attestation. That will also work for a paired attestation if the subscribeKey matches, but it
should be set to Auditor <userId> to allow for subscribeKey rotation.
- Request body:
Standard attestation message in the same format as the Auditor app QR code.
- Response body:
Returns space-separated values in plain text: <subscribeKey> <verifyInterval>. Additional fields
may be added in the future.