openbao

README

openbao

OpenBAO for Kubernetes estates, as reusable mechanism: the two halves the upstream server chart leaves out, the desired state of OpenBAO's own configuration and its apply, and the KMS-rooted CA ceremony its PKI hangs from.

Artifact	What	Status
charts/openbao-ops	Beside the server: snapshots verified before they are stored, a weekly restore that reads data back and walks the restored PKI from a root you hold, an alert before the serving certificate ends, network policies, a serving certificate, and the sidecar that reloads it	unreleased
charts/openbao-consumers	On every consuming cluster: External Secrets stores (readers and writers), cert-manager issuers backed by OpenBAO's PKI, the trust anchors and bundle, and certificates	unreleased
pkg/ceremony (Go)	The CA ceremony with the root key in AWS KMS: the root's self-signature, domain intermediates from OpenBAO-held keys (review a template hash, then sign it once), the break-glass server leaf, and the committed artifact format	unreleased
pkg/custody (Go, Pulumi)	The root key's custody: a multi-region P-384 key per generation, a key policy that separates administration from signing, the two roles, and a Sign alarm in each region	unreleased
pkg/model (Go)	OpenBAO's desired state per namespace and engine: KV mounts, JWT/OIDC auth mounts and roles, identity groups and aliases, policies, PKI mounts with issuers and roles, SSH CAs and roles; yaml-tagged, validated, no loader	unreleased
pkg/apply (Go, Pulumi)	Converges a server onto a pkg/model state with the Pulumi vault provider, after a pre-apply snapshot, with resource names an existing configuration adopts unchanged	unreleased
openbaoctl	The CLI over the ceremony, from a hierarchy file; linux and darwin binaries on every release	unreleased

Charts publish to oci://ghcr.io/truvity/charts/<chart> on every tag, from v0.1.0 on; from v0.2.0 on the same tag is also the Go module github.com/truvity/openbao's version (pkg/model and pkg/apply from v0.3.0 on), and openbaoctl is attached to the GitHub Release.

Who it is for

A platform team running OpenBAO on Kubernetes from upstream's openbao/openbao chart, with cert-manager, trust-manager and External Secrets, that wants backups it has seen restored, a serving certificate that reloads itself and is noticed before it ends, and clusters that read, write and issue through OpenBAO without a stored token. The server is not here: docs/server.md describes the shape these charts assume of it. These charts are what an install is judged on when it fails.

The model and its apply are for a team that configures OpenBAO itself -- its namespaces, logins, policies, PKI and SSH engines -- from a Pulumi Go program, and wants that configuration derived from its own sources, reviewed as a file, and refused before it is applied when it would lock someone out or admit more than it names.

The ceremony and custody are for a team whose OpenBAO PKI should chain to a root nobody can copy: an AWS account holds the root key in KMS, a Pulumi Go program deploys its custody, and a person runs the ceremony with a second person checking the template. They do not create OpenBAO's mounts or roles, and they sign nothing on their own.

The model

Two halves. openbao-ops sits beside the server and owns its operational life: a snapshot is taken, verified and only then stored; a weekly restore opens the newest one in a throwaway server, reads a canary back in every namespace and walks the restored PKI from a root you committed; a daily check alerts weeks before the serving certificate ends; the server is reachable from its clients and the jobs from nothing. openbao-consumers sits on every cluster that uses the server: reader stores bounded by namespace conditions, writer stores that present the writer's own token, and cert-manager issuers whose roots are distributed as a trust bundle. Object storage and alerting are containers with a contract, with S3 and SNS as presets; see docs/doctrine.md.

Inside the server, the desired state (pkg/model) is one level of namespaces -- root, and one per environment -- each holding the same engines: KV, JWT/OIDC doors, identity groups admitted through those doors, policies, PKI mounts whose issuers are self-signed, signed by an earlier issuer or signed outside OpenBAO, and SSH CAs. The estate derives it; pkg/apply writes it, never touching the door it logs in through (docs/model.md).

Above everything sits the root: a KMS key that signs a handful of certificates in its life -- itself, one intermediate per trust domain (whose keys stay in OpenBAO), and a break-glass leaf when OpenBAO cannot issue its own serving certificate. Each signature is a reviewed template, signed once, recorded as a public artifact the estate commits, and announced by an alarm.

Install and a worked example

helm install openbao-ops oci://ghcr.io/truvity/charts/openbao-ops \
  --namespace openbao --values ops-values.yaml

auth:
  mountPath: jwt-example
snapshot:
  enabled: true
  upload:
    s3: { enabled: true, bucket: example-openbao-backups, region: eu-example-1 }
restoreCheck:
  enabled: true
  fetch:
    s3: { enabled: true, bucket: example-openbao-backups, region: eu-example-1 }
  sealConfig: |                     # the snapshot's seal, or a replica of its key
    seal "awskms" {
      region     = "eu-example-2"
      kms_key_id = "alias/openbao-unseal"
    }
certificateExpiry:
  enabled: true
  alert:
    sns: { enabled: true, topicArn: example-topic-arn, region: eu-example-1 }

The serving-certificate reload is a fragment for the upstream chart (docs/safety.md says why, docs/server.md shows the rest of the server's values):

# in the upstream openbao chart's values
server:
  shareProcessNamespace: true
  extraContainers: |
    {{- include "ops.tlsReloadContainer" . | nindent 2 }}

On each consuming cluster:

helm install openbao-consumers oci://ghcr.io/truvity/charts/openbao-consumers \
  --namespace external-secrets --values consumer-values.yaml

server: https://openbao.example.internal:8200
caBundle: <base64 PEM of the CA that signed the SERVER's certificate>
vaultNamespace: devel
auth: { mountPath: jwt-devel }

stores:
  - name: example-app
    conditions: [{ namespaces: [example-app] }]   # required

writers:
  - name: example-writer
    namespace: example-system
    serviceAccount: openbao-writer
    environments: [devel, prod]

pki:
  enabled: true
  trustAnchors:
    - name: example-root-2026
      certificate: <base64 PEM of the ROOT that signs what OpenBAO issues>
  issuers:
    - name: example-private
      signPath: pki/sign/private
      role: example-private

OpenBAO's own configuration, from a Pulumi Go program (docs/model.md has the whole shape):

desired := &model.Desired{
    Bootstrap: operatorsDoor, // declared for review, never applied
    Identity:  model.Identity{PrimaryDoor: "jwt-people"},
    Namespaces: []model.Namespace{{
        Name: "dev",
        KV:   []model.KVMount{{Path: "kv", Canary: "restore-canary"}},
        Auth: []model.JWTMount{{
            Path: "jwt-dev", DiscoveryURL: "https://oidc.dev.example.com",
            Roles: []model.Role{{
                Name: "external-secrets", BoundAudiences: []string{"openbao"},
                BoundSubject: model.ServiceAccountSubject("external-secrets", "external-secrets"),
                UserClaim: "sub", Policies: []string{"eso-app"}, TTL: "1h",
            }},
        }},
        Policies: []model.Policy{{Name: "eso-app", Rules: []model.Rule{
            {Path: "kv/data/app/*", Capabilities: []string{"read"}},
        }}},
    }},
}

_, err := apply.Deploy(c, desired, apply.Options{ // c is the *pulumi.Context
    Address: "https://openbao.example.com",
    Login:   apply.Login{Mount: "jwt-people", Role: "people", Token: operatorToken},
})

For the ceremony, a hierarchy file and one command per step (docs/ceremony.md walks through all of them):

go install github.com/truvity/openbao/cmd/openbaoctl@latest   # or the release archive
openbaoctl pki sign-intermediate --hierarchy pki.yaml --trust-domain private \
  --csr private.csr --print-template                         # no credential; prints the hash
openbaoctl pki sign-intermediate --hierarchy pki.yaml --trust-domain private \
  --csr private.csr --confirm-template <sha256> --role-arn <ceremony role ARN>

// the custody, from a Pulumi Go program
_, err := custody.Deploy(ctx, custody.Args{
    AccountID:                  "111122223333",
    TrustedPrincipalARNPattern: "arn:aws:iam::111122223333:role/example-admin-*",
    AdminRoleName:              "private-pki-root-admin",
    CeremonyRoleName:           "private-pki-root-ceremony",
    Generations:                []custody.Generation{{ID: "example-root-2026-01", Region: "eu-example-1", ReplicaRegion: "eu-example-2"}},
    Notify:                     []string{"security@example.com"},
})

Documentation

• docs/adoption.md — prerequisites, install order, adopting objects that already run, the zero-diff gate
• docs/safety.md — the backup regime, the traps, and every render-time refusal
• docs/reference.md — every value of both charts, the hierarchy file, openbaoctl, pkg/custody, pkg/model and pkg/apply
• docs/doctrine.md — the two halves, the container contracts, and the ownership contract
• docs/server.md — the upstream server's values these charts assume
• docs/ceremony.md — the KMS-rooted CA ceremony, step by step
• docs/custody.md — the root key's policy, roles and Sign alarm
• docs/model.md — OpenBAO's desired state per engine, its apply, and the resource names an existing configuration adopts
• CHANGELOG.md — what changed for a consumer, per version

The rule that makes this repository public

Mechanism only. Nothing here names a cloud, a bucket, a key, a region, a cluster, a hostname or a secret path. Every such thing is an input with a neutral default, and the consuming estate supplies it from its own (private) repository. hack/leak-canary.sh enforces this in CI, and public history cannot be unpublished — so the rule is mechanical, not remembered.

This repository follows the shared component contract.

Status

Used in production by its maintainers. The charts are released from v0.1.0; the Go module and openbaoctl from v0.2.0; pkg/model and pkg/apply arrive in v0.3.0.

Development

devbox shell        # or direnv
just check          # build + lint + golden renders + Go tests + leak canary
just golden         # regenerate tests/golden, the ceremony's template goldens, the model example and the apply's resources — review the diff

tests/invalid/<chart>/ holds one fixture per validation rule. Each must fail to render; just lint proves it. A rule without a fixture is a rule that will quietly stop working.

Releasing

Push a tag vX.Y.Z. The shared release workflow creates the GitHub Release with the openbaoctl binaries and pushes both charts at that version — a chart's own version field is a placeholder that never moves — and the tag is the Go module's version.

The first release is a manual tag: auto-release never cuts one. It is present but not armed (vars.AUTO_RELEASE is unset); when armed it cuts patches only — at once for a merged security-labelled pull request, weekly for dependency bumps. Minors and majors are always manual, tagged when the change merges and after its CHANGELOG heading.

Licence

MIT — see LICENSE.