Document Level Security | Advanced Security

Introduction

Document Level Security (DLS) in Elasticsearch is a powerful feature that allows you to control access to individual documents within an index. This feature is especially useful in multi-tenant environments, where different users or groups of users need to have access to different subsets of documents. By using DLS, you can ensure that users only see the documents they are authorized to view, enhancing the overall security of your Elasticsearch cluster.

Prerequisites

Before you can implement Document Level Security, make sure you have the following:

Elasticsearch installed and running.
Basic understanding of Elasticsearch concepts such as indices, documents, and queries.
Security features enabled in Elasticsearch (e.g., X-Pack).

Creating Roles with Document Level Security

To implement DLS, you need to create roles with specific permissions and DLS queries. Here is an example of how to create a role with DLS:

Example: Creating a Role with DLS

Use the following JSON to create a role that grants access to documents where the field user is equal to "john_doe":

PUT /_security/role/john_doe_role
{
  "indices": [
    {
      "names": [ "my_index" ],
      "privileges": [ "read" ],
      "query": {
        "term": { "user": "john_doe" }
      }
    }
  ]
}

Assigning Roles to Users

After creating the role, you need to assign it to a user. This can be done using the following command:

Example: Assigning a Role to a User

PUT /_security/user/john_doe
{
  "password" : "password123",
  "roles" : [ "john_doe_role" ],
  "full_name" : "John Doe",
  "email" : "john_doe@example.com"
}

Verifying Document Level Security

To verify that DLS is working as expected, you can perform a search query as the user and check the results. Here is an example using the john_doe user:

Example: Verifying DLS

POST /my_index/_search
{
  "query": {
    "match_all": {}
  }
}

If DLS is correctly configured, the search results will only include documents where the user field is equal to "john_doe".

Advanced DLS Queries

DLS queries can be as simple or as complex as needed. You can use any query supported by Elasticsearch, including bool, range, and term queries. Here is an example of a more complex DLS query:

Example: Advanced DLS Query

This query grants access to documents where the user is "john_doe" and the status is "active":

PUT /_security/role/john_doe_role
{
  "indices": [
    {
      "names": [ "my_index" ],
      "privileges": [ "read" ],
      "query": {
        "bool": {
          "must": [
            { "term": { "user": "john_doe" }},
            { "term": { "status": "active" }}
          ]
        }
      }
    }
  ]
}

Performance Considerations

While DLS provides fine-grained access control, it can impact the performance of your Elasticsearch cluster, especially with complex queries and large datasets. Consider the following best practices to mitigate performance issues:

Avoid overly complex DLS queries.
Monitor query performance and adjust as necessary.
Use appropriate hardware and resource allocation to support DLS.

Conclusion

Document Level Security is a crucial feature for controlling access to specific documents within an Elasticsearch index. By following this tutorial, you can set up and verify DLS for your Elasticsearch cluster, ensuring that users only have access to the documents they are authorized to view. Always monitor performance and adjust your configurations to maintain an efficient and secure environment.

Document Level Security in Elasticsearch