Workers authenticate to Boundary using an activation token. They require an
accessible directory defined by `auth_storage_path` for credential storage and
rotation. Transport level communication between the worker & Controller is secured through PKI.
rotation. Transport level communication between the worker & controller is secured through PKI.
Example (not safe for production!):
@ -27,7 +27,7 @@ worker {
## Authorization methods
There are three mechanisms that can be used to initially register a worker to the cluster, Controller-Led, Worker-Led, and registration through an external KMS.
There are three mechanisms that can be used to initially register a worker to the cluster, controller-led, worker-led, and registration through an external KMS.
### Controller-led authorization flow
@ -52,12 +52,16 @@ cluster. Note that this token is one-time-use; it is safe to keep it here even
after the worker has successfully authorized and authenticated, as it will be
unusable at that point.
Note: If this value is not present at worker startup time and the worker is not
<Note>
If this value is not present at worker startup time and the worker is not
authorized, it will print and write out suitable information for the worker-led
flow, described below. If the worker-led flow has not been used to
authorize the worker, and the controller-generated activation token is provided
and the worker restarted, it will make use of it.
</Note>
### Worker-led authorization flow
In this flow, the worker prints out an authorization request token to two
@ -71,20 +75,20 @@ on the CLI this would be via `boundary workers create worker-led
In this flow, the worker authenticates upstream, either to a controller or worker, using a shared KMS provided by the customer. This mechanism auto-registers the worker in addition to authenticating it, and does not require on-disk storage for credentials since each time it connects, it re-authenticates using the trusted KMS.
Optionally with the Multi-Hop workers feature, trusted Workers can authenticate downstream nodes using a separate KMS.
Optionally with the multi-hop workers feature, trusted workers can authenticate downstream nodes using a separate KMS.
Workers using KMS-led authorization require a `name` field. This specifies a unique name of this worker
within the Boundary cluster and _must be unique across workers_. The `name`
within the Boundary cluster and must be unique across workers. The `name`
value can be:
- a direct name string (must be all lowercase)
- a reference to a file on disk (`file://`) from which the name is read
- an env var (`env://`) from which the name is read.
- a reference to a file on disk (`file://`) from which Boundary reads the name
- an env var (`env://`) from which Boundary reads the name
Workers using KMS-led authorization accept an optional `description` field. The `description` value can
be:
- a direct description string
- a reference to a file on disk (`file://`) from which the name is read
- an env var (`env://`) from which the name is read.
- a reference to a file on disk (`file://`) from which Boundary reads the description
- an env var (`env://`) from which Boundary reads the description
```hcl
worker {
@ -94,6 +98,12 @@ worker {
}
```
<Note>
The `name` and `description` fields are not valid configuration fields for workers that use worker-led or controller-led authorization. You can only set these fields through the API and they are only valid for workers that use the [KMS authorization method](/boundary/docs/workers/registration#kms-led-authorization-authentication-flow).
</Note>
Workers using the KMS authorization flow also require a KMS block designated for `worker-auth`. This is the KMS configuration for authentication between the workers and controllers and must be present. Example (not safe for production!):
```hcl
@ -109,7 +119,7 @@ The upstream controller or worker must have a `kms` block that references the
same key and purpose. If both a controller and worker are running as the same
server process, only one stanza is needed.
For Multi-Hop workers, It is also possible to specify a `kms` block with the `downstream-worker-auth` purpose. If specified, this will be a separate KMS that can be used for authenticating new downstream nodes. Blocks with this purpose can be specified multiple times. This allows a single upstream node to authenticate with one key to its own upstream (via the `worker-auth` purpose) and then serve as an authenticating upstream to nodes
For multi-hop workers, it is also possible to specify a `kms` block with the `downstream-worker-auth` purpose. If specified, this will be a separate KMS that can be used for authenticating new downstream nodes. Blocks with this purpose can be specified multiple times. This allows a single upstream node to authenticate with one key to its own upstream (via the `worker-auth` purpose) and then serve as an authenticating upstream to nodes
across various networks, each with their own separate KMS system or key:
```hcl
@ -134,6 +144,20 @@ key; in production you'd want to use a KMS such as AWS KMS, GCP CKMS, Azure
KeyVault, or HashiCorp Vault. For a complete guide to all available KMS types,
refer to [Data encryption in Boundary](/boundary/docs/secure/encryption/data-encryption).
#### KMS configuration
When using controller or worker-led authentication, a worker’s generated activation token is stored in clear-text on disk. Using an external KMS, a worker's credentials can be encrypted by including an optional KMS stanza with the purpose `worker-auth-storage`.
Example (not safe for production!):
```hcl
kms "aead" {
purpose = "worker-auth-storage"
aead_type = "aes-gcm"
key = "X+IJMVT6OnsrIR6G/9OTcJSX+lM9FSPN"
key_id = "worker-auth-storage"
}
```
## Complete configuration example
```hcl
@ -178,25 +202,4 @@ are used to connect to upstream Boundary clusters.
## Resources
For more on how `tags{}` in the above configuration are used to facilitate
routing to the correct target, refer to [Route traffic through a worker](/boundary/docs/workers/worker-tags).
## KMS configuration
When using Controller or Worker-led Authentication, a worker’s generated activation token is stored in clear-text on disk. Using an external KMS, a Workers' credentials can be encrypted by including an optional KMS stanza with the purpose `worker-auth-storage`.
Example (not safe for production!):
```hcl
kms "aead" {
purpose = "worker-auth-storage"
aead_type = "aes-gcm"
key = "X+IJMVT6OnsrIR6G/9OTcJSX+lM9FSPN"
key_id = "worker-auth-storage"
}
```
<Note>
The `name` and `description` fields are not valid configuration fields for workers that use worker-led or controller-led authorization. You can only set these fields through the API and they are only valid for workers that use the [KMS authorization method](/boundary/docs/workers/registration#kms-led-authorization-authentication-flow).
</Note>
routing to the correct target, refer to [Route traffic through a worker](/boundary/docs/workers/worker-tags).
- `name` - Specifies a unique name for the worker. The `name` field is not used for controller-led or worker-led registration, but it is required for KMS-led authorization. The name value can be:
- an all lowercase direct name string
- a reference to a file on disk (`file://`) from which Boundary reads the name
- an environment variable (`env://`) from which Boundary reads the name
- `description` - Specifies an optional description of the worker for workers that use KMS-led authorization. The `description` field is not used for controller-led or worker-led registration. The description value can be:
- a direct description string
- a reference to a file on disk (`file://`) from which Boundary reads the description
- an environment variable (`env://`) from which Boundary reads the description
- `public_addr` - Specifies the public host or IP address (and optionally port)
where clients can reach the worker for proxying. By default, it uses the
address of the listener marked for `proxy` purpose. This is useful for cloud