OpenBao for internal PKI

This document describes how to deploy OpenBao for internal PKI purposes using the StackHPC Hashicorp collection

OpenBao may be used as a Certificate Authority to generate certificates for:

  • OpenStack internal API

  • OpenStack backend APIs

  • RabbitMQ

TLS support is described in the Kolla Ansible documentation and the Kayobe documentation.

OpenBao may also be used as the secret store for Barbican.

Background

Our OpenStack environment employs two separate OpenBao instances. These instances manage the Public Key Infrastructure (PKI) by handling the creation and issuance of certificates.

  • The first OpenBao instance is located on the seed host. It handles infrastructure-level certificates, generating the root Certificate Authority (CA) and intermediate CA for the second OpenBao. The openbao-deploy-seed.yml playbook sets up this instance.

  • The second OpenBao instance is within the OpenStack overcloud, located on the controller nodes. This instance uses the intermediate CA from the seed OpenBao to issue application-specific certificates. The vault-openbao-overcloud.yml playbook is used for its setup. It ensures that all controller nodes trust the intermediate CA from the root OpenBao.

The dual OpenBao setup enhances security by protecting the root CA’s key. The more exposed overcloud OpenBao only possesses the intermediate key, ensuring that the root key remains secure even if the overcloud OpenBao instance is compromised.

Prerequisites

Before beginning the deployment of OpenBao for openstack internal TLS and backend TLS you should ensure that you have the following.

  • Seed Node or a host to run the vault container on

  • Overcloud controller hosts to install second vault on

  • Ansible Galaxy dependencies installed: kayobe control host bootstrap

  • Python dependencies installed: pip install -r kayobe-config/requirements.txt

By default OpenBao image is not synced from Docker Hub to the local Pulp. To sync this image, set stackhpc_sync_openbao_images to true. The OpenBao deployment configuration will be automatically updated to pull images from Pulp.

Deployment

Setup OpenBao on the seed node

  1. Run openbao-deploy-seed.yml custom playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-deploy-seed.yml

  2. Encrypt generated certs/keys with ansible-vault (use proper location of vault password file)

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/openbao/OS-TLS-INT.pem
ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/openbao/seed-openbao-keys.json
ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/openbao/overcloud.key

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/OS-TLS-INT.pem
ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/seed-openbao-keys.json
ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/overcloud.key

Setup OpenBao HA on the overcloud hosts

  1. Run openbao-deploy-overcloud.yml custom playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-deploy-overcloud.yml

  2. Encrypt overcloud openbao keys (use proper location of vault password file)

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/openbao/overcloud-openbao-keys.json

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/overcloud-openbao-keys.json

Rotating OpenBao certificate on the overcloud hosts

The certificate for the overcloud OpenBao has an expiration of one or two years after the certificate was generated. The expiration date of a certificate can be determined with openssl x509 -enddate -noout -in overcloud.crt This will be problematic if anything needs to interact with the OpenBao API such as issuing new certificates or Barbican integration.

  1. Delete the old certificate:

    rm $KAYOBE_CONFIG_PATH/openbao/overcloud.crt

    Or if environments are being used

    rm $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/overcloud.crt

  2. Generate a new certificate (and key):

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-deploy-seed.yml

  3. Encrypt generated key with ansible-vault (use proper location of vault password file)

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/openbao/overcloud.key

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/openbao/overcloud.key

  4. Copy the new certificate to the overcloud hosts. Note, if the old certificate has expired this will fail on the unseal step.

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-deploy-overcloud.yml

  5. Restart the containers to use the new certificate:

    kayobe overcloud host command run --command "docker restart openbao" -l controllers

  6. If sealed, unseal OpenBao:

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-unseal-overcloud.yml

Certificates generation

Note

Generating certificates will fail if the OpenBao on the overcloud is sealed. This will happen whenever the openbao containers are restarted. To unseal the overcloud OpenBao, run:

kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-unseal-overcloud.yml

Create the external TLS certificates (testing only)

This method should only be used for testing. For external TLS on production systems, See Installing External TLS Certificates.

Typically external API TLS certificates should be generated by a organisation’s trusted internal or third-party CA. For test and development purposes it is possible to use OpenBao as a CA for the external API.

  1. Run the playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-generate-test-external-tls.yml

  2. Use ansible-vault to encrypt the PEM bundle in $KAYOBE_CONFIG_PATH/kolla/certificates/haproxy.pem. Commit the PEM bundle to the kayobe configuration.

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/kolla/certificates/haproxy.pem

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/kolla/certificates/haproxy.pem

Create the internal TLS certificates

  1. Run the playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-generate-internal-tls.yml

  2. Use ansible-vault to encrypt the PEM bundle in $KAYOBE_CONFIG_PATH/kolla/certificates/haproxy-internal.pem. Commit the PEM bundle and root CA to the kayobe configuration.

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/kolla/certificates/haproxy-internal.pem

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/kolla/certificates/haproxy-internal.pem

Create the backend TLS and RabbitMQ TLS certificates

  1. Run the playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-generate-backend-tls.yml

  2. Use ansible-vault to encrypt the keys in $KAYOBE_CONFIG_PATH/kolla/certificates/<controller>-key.pem. Commit the certificates and keys to the kayobe configuration.

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/kolla/certificates/<controller>-key.pem

    Or if environments are being used

    ansible-vault encrypt --vault-password-file ~/vault.pass $KAYOBE_CONFIG_PATH/environments/$KAYOBE_ENVIRONMENT/kolla/certificates/<controller>-key.pem

HAProxy integration

It is possible to expose the overcloud OpenBao service via the Kolla Ansible HAProxy load balancer. This provides a single highly available API endpoint, as well as monitoring of the OpenBao backends when combined with Prometheus. HAProxy integration is no longer required for generating OpenStack control plane certificates, making it possible to deploy OpenBao and generate certificates before any containers have been deployed by Kolla Ansible.

  1. Create the HAProxy config to reverse proxy the OpenBao HA container

    Set the openbao_front to the external VIP address or internal VIP address depending on the installation. Set the openbao_back to the IPs of the control nodes.

    Set the following in etc/kayobe/kolla/config/haproxy/services.d/openbao.cfg or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla/config/haproxy/services.d/openbao.cfg

    # Delete "verify none" if not using self-signed/unknown issuer
{% raw %}
frontend openbao_front
   mode tcp
   option tcplog
   bind {{ kolla_internal_vip_address }}:8200
   default_backend openbao_back

backend openbao_back
   mode tcp
   option httpchk GET /v1/sys/health
   # https://openbao.org/api-docs/system/health/
   # 200: initialized, unsealed, and active
   # 429: standby
   http-check expect rstatus (200|429)

{% for host in groups['control'] %}
{% set host_name = hostvars[host].ansible_facts.hostname %}
{% set host_ip = 'api' | kolla_address(host) %}
   server {{ host_name }} {{ host_ip }}:8200 check check-ssl verify none inter 2000 rise 2 fall 5
{% endfor %}
{% endraw %}

  2. If HAProxy has not yet been deployed, continue to certificates deployment. If HAProxy has been deployed, it may be redeployed with the new OpenBao service configuration:

    kayobe overcloud service deploy -kt haproxy

Certificates deployment

Warning

The switch from HTTP to HTTPS during the deployment of internal/backend TLS certificates can temporarily disrupt service availability and necessitates a restart of all services. During this transition, endpoints may become unreachable following the HAProxy restart, persisting until the endpoint catalogue and client have been reconfigured to use HTTPS.

Enable the required TLS variables in kayobe and kolla

  1. If using OpenBao as a CA for the external API, set the following in kayobe-config/etc/kayobe/kolla.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla.yml

    # Whether TLS is enabled for the external API endpoints. Default is 'no'.
kolla_enable_tls_external: yes
kolla_public_openrc_cacert: "{{ '/etc/pki/tls/certs/ca-bundle.crt' if os_distribution in ['centos', 'rocky'] else '/etc/ssl/certs/ca-certificates.crt' }}"

    See Tempest CA certificate for information on adding CA certificates to the trust store when running Tempest.

  2. Set the following in kayobe-config/etc/kayobe/kolla.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla.yml

    # Whether TLS is enabled for the internal API endpoints. Default is 'no'.
kolla_enable_tls_internal: yes
kolla_admin_openrc_cacert: "{{ '/etc/pki/tls/certs/ca-bundle.crt' if os_distribution in ['centos', 'rocky'] else '/etc/ssl/certs/ca-certificates.crt' }}"

    See OpenStack Capacity for information on adding CA certificates to the trust store when deploying the OpenStack Capacity exporter.

  3. Set the following in etc/kayobe/kolla/globals.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla/globals.yml

    # Internal TLS configuration
# Copy the self-signed CA into the kolla containers
kolla_copy_ca_into_containers: "yes"
# Use the following trust store within the container
openstack_cacert: "{{ '/etc/pki/tls/certs/ca-bundle.crt' if os_distribution == 'rocky' else '/etc/ssl/certs/ca-certificates.crt' }}"

# Backend TLS config
# Enable backend TLS
kolla_enable_tls_backend: "yes"

# If using RabbitMQ TLS:
rabbitmq_enable_tls: "yes"

  4. Deploy OpenStack

    Warning

    It is important that you are only using admin endpoints for keystone. If any admin endpoints exist for other services, they must be deleted e.g.

    openstack endpoint list --interface admin -f value | \
awk '!/keystone/ {print $1}' | xargs openstack endpoint delete

    kayobe overcloud service deploy

    If VM provisioning fails with an error with this format:

    Unable to establish connection to http://<kolla internal vip/fqdn>:9696/v2.0/ports/some-sort-of-uuid: Connection aborted

    Restart the nova-compute container on all hypervisors:

    kayobe overcloud host command run --command "systemctl restart kolla-nova_compute-container.service" --become --show-output -l compute

Barbican integration

Barbican integration depends on HAProxy integration.

Enable Barbican in kayobe

  1. Set the following in kayobe-config/etc/kayobe/kolla.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla.yml

    kolla_enable_barbican: yes

Generate secrets_barbican_approle_secret_id

  1. Run uuidgen to generate secret id

  2. Insert into secrets.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/secrets.yml

    secrets_barbican_approle_secret_id: "YOUR-SECRET-GOES-HERE"

Create required configuration in OpenBao

  1. Run openbao-deploy-barbican.yml custom playbook

    kayobe playbook run $KAYOBE_CONFIG_PATH/ansible/openbao-deploy-barbican.yml

Add secrets_barbican_approle_id to secrets

  1. Note the role id from playbook output and insert into secrets.yml or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/secrets.yml

    secrets_barbican_approle_role_id: "YOUR-APPROLE-ID-GOES-HERE"

Configure Barbican

  1. Put required configuration in kayobe-config/etc/kayobe/kolla/config/barbican.conf or if environments are being used etc/kayobe/environments/$KAYOBE_ENVIRONMENT/kolla/config/barbican.conf

    [secretstore]
namespace=barbican.secretstore.plugin
enable_multiple_secret_stores=false
enabled_secretstore_plugins=vault_plugin

[vault_plugin]
vault_url = https://{{ kolla_internal_fqdn }}:8200
use_ssl = True
{% raw %}
ssl_ca_crt_file = {{ openstack_cacert }}
{% endraw %}
approle_role_id = {{ secrets_barbican_approle_role_id }}
approle_secret_id = {{ secrets_barbican_approle_secret_id }}
kv_mountpoint = barbican

Deploy Barbican

kayobe overcloud service deploy -kt barbican