Vault Authentication plugin

Kong Enterprise only: This plugin is only available with a Kong Enterprise subscription.

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Add authentication to a Service or Route with an access token and secret token. Credential tokens are stored securely via Vault. Credential lifecyles can be managed through the Kong Admin API, or independantly via Vault.

Terminology

plugin: a plugin executing actions inside Kong before or after a request has been proxied to the upstream API.
Service: the Kong entity representing an external upstream API or microservice.
Route: the Kong entity representing a way to map downstream requests to upstream services.
upstream service: this refers to your own API/service sitting behind Kong, to which client requests are forwarded.

Configuration

Enabling the plugin on a Service

With a database

Configure this plugin on a Service by making the following request:

$ curl -X POST http://kong:8001/services/{service}/plugins \
    --data "name=vault-auth"  \
    --data "config.access_token_name=access_token" \
    --data "config.vault=" \
    --data "config.secret_token_name=access_token"

Without a database

Configure this plugin on a Service by adding this section do your declarative configuration file:

plugins:
- name: vault-auth
  service: {service}
  config: 
    access_token_name: access_token
    vault: 
    secret_token_name: access_token

In both cases, {service} is the id or name of the Service that this plugin configuration will target.

Enabling the plugin on a Route

With a database

Configure this plugin on a Route with:

$ curl -X POST http://kong:8001/routes/{route}/plugins \
    --data "name=vault-auth"  \
    --data "config.access_token_name=access_token" \
    --data "config.vault=" \
    --data "config.secret_token_name=access_token"

Without a database

Configure this plugin on a Route by adding this section do your declarative configuration file:

plugins:
- name: vault-auth
  route: {route}
  config: 
    access_token_name: access_token
    vault: 
    secret_token_name: access_token

In both cases, {route} is the id or name of the Route that this plugin configuration will target.

Global plugins

Using a database, all plugins can be configured using the http://kong:8001/plugins/ endpoint.
Without a database, all plugins can be configured via the plugins: entry on the declarative configuration file.

A plugin which is not associated to any Service, Route or Consumer (or API, if you are using an older version of Kong) is considered "global", and will be run on every request. Read the Plugin Reference and the Plugin Precedence sections for more information.

Parameters

Here's a list of all the parameters which can be used in this plugin's configuration:

form parameter	default	description
`name`		The name of the plugin to use, in this case `vault-auth`
`service_id`		The id of the Service which this plugin will target.
`route_id`		The id of the Route which this plugin will target.
`enabled`	`true`	Whether this plugin will be applied.
`config.access_token_name`	`access_token`	Describes an array of comma separated parameter names where the plugin will look for an access token. The client must send the access token in one of those key names, and the plugin will try to read the credential from a header or the querystring parameter with the same name. note: the key names may only contain [a-z], [A-Z], [0-9], [_] and [-].
`config.vault`		A reference to an existing `vault` objection within the database. `vault` entities define the connection and authentication parameters used to connection to a Vault HTTP(S) API.
`config.secret_token_name`	`access_token`	Describes an array of comma separated parameter names where the plugin will look for a secret token. The client must send the secret in one of those key names, and the plugin will try to read the credential from a header or the querystring parameter with the same name. note: the key names may only contain [a-z], [A-Z], [0-9], [_] and [-].
`config.key_in_body` optional	`false`	If enabled, the plugin will read the request body (if said request has one and its MIME type is supported) and try to find the key in it. Supported MIME types are `application/www-form-urlencoded`, `application/json`, and `multipart/form-data`.
`config.hide_credentials` optional	`false`	An optional boolean value telling the plugin to show or hide the credential from the upstream service. If `true`, the plugin will strip the credential from the request (i.e. the header or querystring containing the key) before proxying it.
`config.anonymous` optional		An optional string (consumer uuid) value to use as an “anonymous” consumer if authentication fails. If empty (default), the request will fail with an authentication failure `4xx`. Please note that this value must refer to the Consumer `id` attribute which is internal to Kong, and not its `custom_id`.
`config.run_on_preflight` optional	`true`	A boolean value that indicates whether the plugin should run (and try to authenticate) on `OPTIONS` preflight requests, if set to `false` then `OPTIONS` requests will always be allowed.

Usage

In order to use the plugin, you first need to create a Consumer to associate one or more credentials to. The Consumer represents a developer using the upstream service. Additionally, a Vault object must be created to represent the connection Kong will use to communicate with a Vault server, where access and secret tokens will be stored.

Create a Consumer

You need to associate a credential to an existing [Consumer][consumer-object] object. To create a Consumer, you can execute the following request:

$ curl -X POST http://kong:8001/consumers/ \
    --data "username=<USERNAME>" \
    --data "custom_id=<CUSTOM_ID>"
HTTP/1.1 201 Created

{
    "username":"<USERNAME>",
    "custom_id": "<CUSTOM_ID>",
    "created_at": 1472604384000,
    "id": "7f853474-7b70-439d-ad59-2481a0a9a904"
}

parameter	default	description
`username` semi-optional		The username of the Consumer. Either this field or `custom_id` must be specified.
`custom_id` semi-optional		A custom identifier used to map the Consumer to another database. Either this field or `username` must be specified.

A [Consumer][consumer-object] can have many credentials.

If you are also using the ACL plugin and whitelists with this service, you must add the new consumer to a whitelisted group. See [ACL: Associating Consumers][acl-associating] for details.

Create a Vault

A Vault object represents the connection between Kong and a Vault server. It defines the connection and authentication information used to communicate with the Vault API. This allows different instances of the vault-auth plugin to communicate with different Vault servers, providing a flexible deployment and consumption model.

Vault objects can be created via the following HTTP request:

$ curl -X POST http://kong:8001/vaults \
  --data name=kong-auth \
  --data mount=kong-auth \
  --data protocol=http \
  --data host=127.0.0.1 \
  --data port=8200
  --data token=s.m3w9gdV0uMDYFpMgEWSB2mtM
HTTP/1.1 201 Created

{
    "created_at": 1550538643,
    "host": "127.0.0.1",
    "id": "d3da058d-0acb-49c2-b7fe-72b3e9fd4b0a",
    "mount": "kong-auth",
    "name": "kong-auth",
    "port": 8200,
    "protocol": "http",
    "token": "s.m3w9gdV0uMDYFpMgEWSB2mtM",
    "updated_at": 1550538643
}

This assumes a Vault server is accessible via 127.0.0.1:8200, and that a version 1 KV secrets engine has been enabled at kong-auth. Vault KV secrets engine documentation is available via the Vault documentation.

Create an Access/Secret Token Pair

vault-auth credentials are defined as a pair of tokens: an access token that identifies the owner of the credential, and a secret token that is used to authenticate ownership of the access token.

Token pairs can be managed either via the Kong Admin API, or independantly via direct access with Vault. Token pairs must be associated with an existing Kong Consumer. Creating a token pair with the Kong Admin API can be done via the following request:

$ curl -X POST http://kong:8001/vaults/{vault}/credentials/{consumer}
HTTP/1.1 201 Created

{
    "data": {
        "access_token": "v3cOV1jWglS0PFOrTcdr85bs1GP0e2yM",
        "consumer": {
            "id": "64063284-e3b5-48e7-9bca-802251c32138"
        },
        "created_at": 1550538920,
        "secret_token": "11XYyybbu3Ty0Qt4ImIshPGQ0WsvjLzl",
        "ttl": null
    }
}

When the access_token or secret_token values are not provided, token values will be automatically generated via a cryptographically-secure random number generator (CSPRNG).

Integrating Vault objects with Vault-Auth plugins

Vault objects are treated as foreign references in plugin configs, creating a seamless lifecycle relationship between Vault instances and plugins with which they’re associated. vault-auth plugins require an association with a Vault object, which can be defined with the following HTTP request during plugin creation:

$ curl -X POST http://kong:8001/plugins \
  --data name=vault-auth \
  --data config.vault.id=<uuid>
HTTP/1.1 201 Created

{
  "created_at": 1550539002,
  "config": {
    "tokens_in_body": false,
    "secret_token_name": "secret_token",
    "run_on_preflight": true,
    "vault": {
      "id": "d3da058d-0acb-49c2-b7fe-72b3e9fd4b0a"
    },
    "anonymous": null,
    "hide_credentials": false,
    "access_token_name": "access_token"
  },
  "id": "b4d0cbb7-bff2-4599-ba19-67c705c15b9a",
  "service": null,
  "enabled": true,
  "run_on": "first",
  "consumer": null,
  "route": null,
  "name": "vault-auth"
}

Where <uuid> is the id of an existing Vault object.

Using Vault credentials

Simply make a request with the access_token and secret_token as querystring parameters:

$ curl http://kong:8000/{proxy path}?access_token=<access token>&secret_token=<secret token>

Or in a header:

$ curl http://kong:8000/{proxy path} \
    -H 'access_token: <access_token>' \
    -H 'secret_token: <secret_token>'

Deleting an Access/Secret Token Pair

Existing Vault credentials can be removed from the Vault server via the following API:

$ curl -X DELETE http://kong:8001/vaults/{vault}/credentials/token/{access token}

HTTP/1.1 204 No Content

Token TTL

When reading a token from Vault, Kong will search the responding KV value for the presence of a ttl field. When this is present, Kong will respect the advisory value of the ttlfield and store the value of the credential in cache for only as long as the ttl field defines. This allows tokens created directly in Vault, outside of the Kong Admin API, to be periodically refreshed by Kong.

Extra-Kong Token Pairs

Kong can read access/token secret pairs that have been created directly in Vault, outside of the Kong Admin API. Currently vault-auth supports creating and reading credentials based on the Vault v1 KV engine. Create Vault KV secret values must contain the following fields:

{
  access_token: <string>
  secret_token: <string>
  created_at: <integer>
  updated_at: <integer>
  ttl: <integer> (optional)
  consumer: {
    id: <uuid>
  }
}

Additional fields within the secret are ignored. The key must be the access_token value; this is the identifier by which Kong queries the Vault API to fetch the credential data. See the Vault documentation for further information on the KV v1 secrets engine.

vault-auth token pairs can be created with the Vault HTTP API or the vault write command:

$ vault write kong-auth/foo - <<EOF
{
  "access_token": "foo",
  "secret_token": "supersecretvalue",
  "consumer": {
    "id": "ce67c25e-2168-4a09-81e5-e06187a2384f"
  },
  "ttl": 86400
}
EOF

About this Plugin
Made by
Categories	Authentication
Bundled with...
Kong Enterprise 0.35-x