Each permission in the Security plugin controls access to some action that the OpenSearch cluster can perform, such as indexing a document or checking cluster health.
Most permissions are self-describing. For example, `cluster:admin/ingest/pipeline/get` lets you retrieve information about ingest pipelines. _In many cases_, a permission correlates to a specific REST API operation, such as `GET _ingest/pipeline`.
Despite this correlation, permissions do **not** directly map to REST API operations. Operations such as `POST _bulk` and `GET _msearch` can access many indexes and perform many actions in a single request. Even a simple request, such as `GET _cat/nodes`, performs several actions in order to generate its response.
For this request to succeed, you must have the following permissions for `test-index`:
- indices:data/write/bulk*
- indices:data/write/delete
- indices:data/write/index
- indices:data/write/update
These permissions also allow you add, update, or delete documents (e.g. `PUT test-index/_doc/tt0816711`), because they govern the underlying OpenSearch actions of indexing and deleting documents rather than a specific API path and HTTP method.
If you want a user to have the absolute minimum set of permissions necessary to perform some function—the [principle of least privilege](https://en.wikipedia.org/wiki/Principle_of_least_privilege)—the best way is to send representative requests to your cluster as a new test user. In the case of a permissions error, the Security plugin is very explicit about which permissions are missing. Consider this request and response:
[Create a user and a role]({{site.url}}{{site.baseurl}}/security/access-control/users-roles/), map the role to the user, and start sending signed requests using curl, Postman, or any other client. Then gradually add permissions to the role as you encounter errors. Even after you resolve one permissions error, the same request might generate new errors; the plugin only returns the first error it encounters, so keep trying until the request succeeds.
Rather than individual permissions, you can often achieve your desired security posture using a combination of the default action groups. See [Default action groups]({{site.url}}{{site.baseurl}}/security/access-control/default-action-groups/) for descriptions of the permissions that each group grants.
System index permissions are unique among other permissions in that they extend some traditional admin-only accessibility to non-admin users. These permissions give normal users the ability to modify any system index specified in the role or roles to which they are mapped. The exception to this is the security system index, `.opendistro_security`, which is used to store the Security plugin's configuration YAML files and remains accessible only to admins with an admin certificate.
Along with standard index permissions, you specify system index permissions in the `roles.yml` configuration file under `index_permissions` (see [roles.yml]({{site.url}}{{site.baseurl}}/security/configuration/yaml/#rolesyml)). This involves a two-step process: 1) adding the system index in the `index_patterns` section and 2) specifying `system:admin/system_index` in the role's `allowed_actions` section.
For example, the system index permission that gives a user permission to modify the system index that stores configurations for the Alerting plugin is defined by the index pattern `.opendistro-alerting-config`, and its allowed action is defined as `system:admin/system_index`. The following role shows how this system index permission is configured along with other attributes:
```yml
alerting-role:
reserved: true
hidden: false
cluster_permissions:
- 'cluster:admin/opendistro/alerting/alerts/ack'
- 'cluster:admin/opendistro/alerting/alerts/get'
index_permissions:
- index_patterns:
- .opendistro-alerting-config
- allowed_actions:
- 'system:admin/system_index'
```
{% include copy.html %}
System index permissions also work with the wildcard to include all variations of a partial system index name. This can be useful, but it should be used with caution to avoid giving unintentional access to system indexes. When specifying system indexes for roles, keep the following considerations in mind:
* Specifying the full name of a system index limits access to only that index: `.opendistro-alerting-config`.
* Specifying a partial name for a system index along with the wildcard provides access to all system indexes that begin with that name: `.opendistro-anomaly-detector*`.
* Although not recommended---given the wide-reaching access granted by this role definition---using `*` for the index pattern along with `system:admin/system_index` as an allowed action grants access to all system indexes.
Entering the wildcard `*` by itself under `allowed_actions` does not automatically grant access to system indexes. The allowed action `system:admin/system_index` must be explicitly added.
The following example shows a role that grants access to all system indexes:
```yml
index_permissions:
- index_patterns:
- '*'
- allowed_actions:
- 'system:admin/system_index'
```
### Verifying system index access
You can use the [CAT indices]({{site.url}}{{site.baseurl}}/api-reference/cat/cat-indices/) operation to see all indexes associated with any index pattern in your permissions configuration and verify that the permissions provide the access you intended. For example, if you want to verify a permission that includes system indexes beginning with the prefix `.kibana`, you can run the `GET /_cat/indices/.kibana*` call to return all indexes associated with that prefix.
The following example response shows the three system indexes associated with the index pattern `.kibana*`:
```json
health | status | index | uuid | pri | rep | docs.count | docs.deleted | store.size | pri.store.size
green open .kibana_1 XmTePICFRoSNf5O5uLgwRw 1 1 220 0 468.3kb 232.1kb
green open .kibana_2 XmTePICFRoSNf5O5uLgwRw 1 1 220 0 468.3kb 232.1kb
green open .kibana_3 XmTePICFRoSNf5O5uLgwRw 1 1 220 0 468.3kb 232.1kb
```
### Enabling system index permissions
Users that have the permission [`restapi:admin/roles`]({{site.url}}{{site.baseurl}}/security/access-control/api/#access-control-for-the-api) are able to map system index permissions to all users in the same way they would for a cluster or index permission in the `roles.yml` file. However, to preserve some control over this permission, the `plugins.security.system_indices.permissions.enabled` setting allows you to enable or disable the system index permissions feature. This setting is disabled by default. To enable the system index permissions feature, set `plugins.security.system_indices.permissions.enabled` to `true`. For more information about this setting, see [Enabling user access to system indexes]({{site.url}}{{site.baseurl}}/security/configuration/yaml/#enabling-user-access-to-system-indexes).
Keep in mind that enabling this feature and mapping system index permissions to normal users gives those users access to indexes that may contain sensitive information and configurations essential to a cluster's health. We also recommend caution when mapping users to `restapi:admin/roles` because this permission gives a user not only the ability to assign the system index permission to another user but also the ability to self-assign access to any system index.
These permissions are for the cluster and can't be applied granularly. For example, you either have permissions to take snapshots (`cluster:admin/snapshot/create`) or you don't. The cluster permission, therefore, cannot grant a user privileges to take snapshots of a select set of indexes while preventing the user from taking snapshots of others.
Cross-references to API documentation in the permissions that follow are only intended to provide an understanding of the permissions. As stated at the beginning of this section, permissions often correlate to APIs but do not map directly to them.
{: .note }
### Ingest API permissions
See [Ingest APIs]({{site.url}}{{site.baseurl}}/api-reference/ingest-apis/index/).
See [API tools]({{site.url}}{{site.baseurl}}/security-analytics/api-tools/index/).
| **Permission** | **Description** |
| :--- | :--- |
| cluster:admin/opensearch/securityanalytics/alerts/get | Permission to get alerts |
| cluster:admin/opensearch/securityanalytics/alerts/ack | Permission to acknowledge alerts |
| cluster:admin/opensearch/securityanalytics/detector/get | Permission to get detectors |
| cluster:admin/opensearch/securityanalytics/detector/search | Permission to search detectors |
| cluster:admin/opensearch/securityanalytics/detector/write | Permission to create and update detectors |
| cluster:admin/opensearch/securityanalytics/detector/delete | Permission to delete detectors |
| cluster:admin/opensearch/securityanalytics/findings/get | Permission to get findings |
| cluster:admin/opensearch/securityanalytics/mapping/get | Permission to get field mappings by index |
| cluster:admin/opensearch/securityanalytics/mapping/view/get | Permission to get field mappings by index and view mapped and unmapped fields |
| cluster:admin/opensearch/securityanalytics/mapping/create | Permission to create field mappings |
| cluster:admin/opensearch/securityanalytics/mapping/update | Permission to update field mappings |
| cluster:admin/opensearch/securityanalytics/rules/categories | Permission to get all rule categories |
| cluster:admin/opensearch/securityanalytics/rule/write | Permission to create and update rules |
| cluster:admin/opensearch/securityanalytics/rule/search | Permission to search for rules |
| cluster:admin/opensearch/securityanalytics/rules/validate | Permission to validate rules |
| cluster:admin/opensearch/securityanalytics/rule/delete | Permission to delete rules |
### Monitoring permissions
Cluster permissions for monitoring the cluster apply to read-only operations, such as checking cluster health and getting information about usage on nodes or tasks running in the cluster.
See [REST API reference]({{site.url}}{{site.baseurl}}/api-reference/index/).
These permissions apply to an index or index pattern. You might want a user to have read access to all indexes (that is, `*`), but write access to only a few (for example, `web-logs` and `product-catalog`).
These permissions apply to REST APIs to control access to the endpoints. Granting access to any of these will allow a user the permission to change fundamental operational components of the Security plugin.
Allowing access to these endpoints has the potential to trigger operational changes in the cluster. Proceed with caution.
