Export Teleport Audit Events to the Elastic Stack

Teleport's Event Handler plugin receives audit events from the Teleport Auth Service and forwards them to your log management solution, letting you perform historical analysis, detect unusual behavior, and form a better understanding of how users interact with your Teleport cluster.

In this guide, we will show you how to configure Teleport's Event Handler plugin to send your Teleport audit events to the Elastic Stack. In this setup, the Event Handler plugin forwards audit events from Teleport to Logstash, which stores them in Elasticsearch for visualization and alerting in Kibana.

Prerequisites

tctl version
Teleport v14.2.1 git:api/14.0.0-gd1e081e go1.21
  
tsh version
Teleport v14.2.1 go1.21
Proxy version: 14.2.1Proxy: teleport.example.com

tctl version
Teleport Enterprise v14.1.3 git:api/14.0.0-gd1e081e go1.21
  
tsh version
Teleport v14.1.3 go1.21
Proxy version: 14.1.3Proxy: teleport.example.com

tctl version
Teleport Enterprise v14.2.1 git:api/14.0.0-gd1e081e go1.21
  
tsh version
Teleport v14.2.1 go1.21
Proxy version: 14.2.1Proxy: teleport.example.com

tctl version
Teleport Enterprise v14.1.3 git:api/14.0.0-gd1e081e go1.21
  
tsh version
Teleport v14.1.3 go1.21
Proxy version: 14.1.3Proxy: teleport.example.com

• Logstash version 8.4.1 or above running on a Linux host. In this guide, you will also run the Event Handler plugin on this host.

• Elasticsearch and Kibana version 8.4.1 or above, either running via an Elastic Cloud account or on your own infrastructure. You will need permissions to create and manage users in Elasticsearch.

  We have tested this guide on the Elastic Stack version 8.4.1.

Step 1/4. Set up the Event Handler plugin

The Event Handler plugin is a binary that runs independently of your Teleport cluster. It authenticates to your Teleport cluster and Logstash using mutual TLS. In this section, you will install the Event Handler plugin on the Linux host where you are running Logstash and generate credentials that the plugin will use for authentication.

Install the Event Handler plugin

Follow the instructions for your environment to install the Event Handler plugin on your Logstash host:

curl -L -O https://get.gravitational.com/teleport-event-handler-v14.2.1-linux-amd64-bin.tar.gz
tar -zxvf teleport-event-handler-v14.2.1-linux-amd64-bin.tar.gz
sudo ./teleport-event-handler/install

curl -L -O https://get.gravitational.com/teleport-event-handler-v14.2.1-darwin-amd64-bin.tar.gz
tar -zxvf teleport-event-handler-v14.2.1-darwin-amd64-bin.tar.gz
sudo ./teleport-event-handler/install

docker pull public.ecr.aws/gravitational/teleport-plugin-event-handler:14.2.1

helm repo add teleport https://charts.releases.teleport.dev

helm repo update

git clone https://github.com/gravitational/teleport-plugins.git --depth 1
cd teleport-plugins/event-handler/build.assets
make build

git clone https://github.com/gravitational/teleport-plugins.git --depth 1
cd teleport-plugins/event-handler
go build

Generate a starter config file

Generate a configuration file with placeholder values for the Teleport Event Handler plugin. Later in this guide, we will edit the configuration file for your environment.

teleport-event-handler configure . mytenant.teleport.sh:443

teleport-event-handler configure . teleport.example.com:443

TELEPORT_CLUSTER_ADDRESS=mytenant.teleport.sh:443
docker run -v `pwd`:/opt/teleport-plugin -w /opt/teleport-plugin public.ecr.aws/gravitational/teleport-plugin-event-handler:14.2.1 configure . ${TELEPORT_CLUSTER_ADDRESS?}

kubectl create secret generic teleport-event-handler-client-tls --from-file=ca.crt=ca.crt,client.crt=client.crt,client.key=client.key

You'll see the following output:

Teleport event handler 14.2.1

[1] mTLS Fluentd certificates generated and saved to ca.crt, ca.key, server.crt, server.key, client.crt, client.key
[2] Generated sample teleport-event-handler role and user file teleport-event-handler-role.yaml
[3] Generated sample fluentd configuration file fluent.conf
[4] Generated plugin configuration file teleport-event-handler.toml

The plugin generates several setup files:

ls -l
-rw------- 1 bob bob     1038 Jul  1 11:14 ca.crt
-rw------- 1 bob bob     1679 Jul  1 11:14 ca.key
-rw------- 1 bob bob     1042 Jul  1 11:14 client.crt
-rw------- 1 bob bob     1679 Jul  1 11:14 client.key
-rw------- 1 bob bob      541 Jul  1 11:14 fluent.conf
-rw------- 1 bob bob     1078 Jul  1 11:14 server.crt
-rw------- 1 bob bob     1766 Jul  1 11:14 server.key
-rw------- 1 bob bob      260 Jul  1 11:14 teleport-event-handler-role.yaml
-rw------- 1 bob bob      343 Jul  1 11:14 teleport-event-handler.toml

teleport-event-handler configure --cn=handler.example.com --dns-names=forwarder.example.com

We'll re-purpose the files generated for Fluentd in our Logstash configuration.

Define RBAC resources

The teleport-event-handler configure command generated a file called teleport-event-handler-role.yaml. This file defines a teleport-event-handler role and a user with read-only access to the event API:

kind: role
metadata:
  name: teleport-event-handler
spec:
  allow:
    rules:
      - resources: ['event', 'session']
        verbs: ['list','read']
version: v5
---
kind: user
metadata:
  name: teleport-event-handler
spec:
  roles: ['teleport-event-handler']
version: v2

Move this file to your workstation (or recreate it by pasting the snippet above) and use tctl on your workstation to create the role and the user:

tctl create -f teleport-event-handler-role.yaml
user "teleport-event-handler" has been created
role 'teleport-event-handler' has been created

ERROR: tctl must be either used on the auth server or provided with the identity file via --identity flag

Enable impersonation of the Event Handler plugin user

In order for the Event Handler plugin to forward events from your Teleport cluster, it needs signed credentials from the cluster's certificate authority. The teleport-event-handler user cannot request this itself, and requires another user to impersonate this account in order to request credentials.

Create a role that enables your user to impersonate the teleport-event-handler user. First, paste the following YAML document into a file called teleport-event-handler-impersonator.yaml:

kind: role
version: v5
metadata:
  name: teleport-event-handler-impersonator
spec:
  options:
    # max_session_ttl defines the TTL (time to live) of SSH certificates
    # issued to the users with this role.
    max_session_ttl: 10h

  # This section declares a list of resource/verb combinations that are
  # allowed for the users of this role. By default nothing is allowed.
  allow:
    impersonate:
      users: ["teleport-event-handler"]
      roles: ["teleport-event-handler"]

Next, create the role:

tctl create teleport-event-handler-impersonator.yaml

Assign the teleport-event-handler-impersonator role to your Teleport user by running the appropriate commands for your authentication provider:

Export the access plugin identity

Like all Teleport users, teleport-event-handler needs signed credentials in order to connect to your Teleport cluster. You will use the tctl auth sign command to request these credentials.

The following tctl auth sign command impersonates the teleport-event-handler user, generates signed credentials, and writes an identity file to the local directory:

tctl auth sign --user=teleport-event-handler --out=auth.pem

The plugin connects to the Teleport Auth Service's gRPC endpoint over TLS.

The identity file, auth.pem, includes both TLS and SSH credentials. The plugin uses the SSH credentials to connect to the Proxy Service, which establishes a reverse tunnel connection to the Auth Service. The plugin uses this reverse tunnel, along with your TLS credentials, to connect to the Auth Service's gRPC endpoint.

tsh login --proxy=teleport.example.com --ttl=60060

Step 2/4. Configure a Logstash pipeline

The Event Handler plugin forwards audit logs from Teleport by sending HTTP requests to a user-configured endpoint. We will define a Logstash pipeline that handles these requests, extracts logs, and sends them to Elasticsearch.

Create a role for the Event Handler plugin

Your Logstash pipeline will require permissions to create and manage Elasticsearch indexes and index lifecycle management policies, plus get information about your Elasticsearch deployment. Create a role with these permissions so you can later assign it to the Elasticsearch user you will create for the Event Handler.

In Kibana, navigate to "Management" > "Roles" and click "Create role". Enter the name teleport-plugin for the new role. Under the "Elasticsearch" section, under "Cluster privileges", enter manage_index_templates, manage_ilm, and monitor.

Under "Index privileges", define an entry with audit-events-* in the "Indices" field and write and manage in the "Privileges" field. Click "Create role".

Create an Elasticsearch user for the Event Handler

Create an Elasticsearch user that Logstash can authenticate as when making requests to the Elasticsearch API.

In Kibana, find the hamburger menu on the upper left and click "Management", then "Users" > "Create user". Enter teleport for the "Username" and provide a secure password.

Assign the user the teleport-plugin role we defined earlier.

Prepare TLS credentials for Logstash

Later in this guide, your Logstash pipeline will use an HTTP input to receive audit events from the Teleport Event Handler plugin.

Logstash's HTTP input can only sign certificates with a private key that uses the unencrypted PKCS #8 format. When you ran teleport-event-handler configure earlier, the command generated an encrypted RSA key. We will convert this key to PKCS #8.

You will need a password to decrypt the RSA key. To retrieve this, execute the following command in the directory where you ran teleport-event-handler configure:

cat fluent.conf | grep passphrase
private_key_passphrase "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"

Convert the encrypted RSA key to an unencrypted PKCS #8 key. The command will prompt your for the password you retrieved:

openssl pkcs8 -topk8 -in server.key -nocrypt -out pkcs8.key

Enable Logstash to read the new key, plus the CA and certificate we generated earlier:

chmod +r pkcs8.key ca.crt server.crt

Define an index template

When the Event Handler plugin sends audit events to Logstash, Logstash needs to know how to parse these events to forward them to Elasticsearch. You can define this logic using an index template, which Elasticsearch uses to construct an index for data it receives.

Create a file called audit-events.json with the following content:

{
  "index_patterns": ["audit-events-*"],
  "template": {
    "settings": {},
    "mappings": {
      "dynamic":"true"
    }
  }
}

This index template modifies any index with the pattern audit-events-*. Because it includes the "dynamic": "true" setting, it instructs Elasticsearch to define index fields dynamically based on the events it receives. This is useful for Teleport audit events, which use a variety of fields depending on the event type.

Define a Logstash pipeline

On the host where you are running Logstash, create a configuration file that defines a Logstash pipeline. This pipeline will receive logs from port 9601 and forward them to Elasticsearch.

On the host running Logstash, create a file called /etc/logstash/conf.d/teleport-audit.conf with the following content:

input {
  http {
    port => 9601
    ssl =>  true
    ssl_certificate => "/home/server.crt"
    ssl_key =>  "/home/pkcs8.key"
    ssl_certificate_authorities => [
      "/home/ca.crt"
    ]
    ssl_verify_mode => "force_peer"
  }
}
output {
  elasticsearch {
    user => "teleport"
    password => "ELASTICSEARCH_PASSPHRASE"
    template_name => "audit-events"
    template => "/home/audit-events.json"
    index => "audit-events-%{+yyyy.MM.dd}"
    template_overwrite => true
  }
}

In the input.http section, update ssl_certificate and ssl_certificate_authorities to include the locations of the server certificate and certificate authority files that the teleport-event-handler configure command generated earlier.

Logstash will authenticate client certificates against the CA file and present a signed certificate to the Teleport Event Handler plugin.

Edit the ssl_key field to include the path to the pkcs8.key file we generated earlier.

In the output.elasticsearch section, edit the following fields depending on whether you are using Elastic Cloud or your own Elastic Stack deployment:

  elasticsearch {
    cloud_id => "CLOUD_ID"
    cloud_auth => "teleport:PASSWORD" 
    template_name => "audit-events"
    template => "/home/audit-events.json"
    index => "audit-events-%{+yyyy.MM.dd}"
    template_overwrite => true
  }

  elasticsearch {
    hosts => "elasticsearch.example.com"
    user => "teleport" 
    password => "PASSWORD" 
    template_name => "audit-events"
    template => "/home/audit-events.json"
    index => "audit-events-%{+yyyy.MM.dd}"
    template_overwrite => true
  }

Finally, modify template to point to the path to the audit-events.json file you created earlier.

Because the index template we will create with this file applies to indices with the prefix audit-events-*, and we have configured our Logstash pipeline to create an index with the title "audit-events-%{+yyyy.MM.dd}, Elasticsearch will automatically index fields from Teleport audit events.

Disable the Elastic Common Schema for your pipeline

The Elastic Common Schema (ECS) is a standard set of fields that Elastic Stack uses to parse and visualize data. Since we are configuring Elasticsearch to index all fields from your Teleport audit logs dynamically, we will disable the ECS for your Logstash pipeline.

On the host where you are running Logstash, edit /etc/logstash/pipelines.yml to add the following entry:

- pipeline.id: teleport-audit-logs
  path.config: "/etc/logstash/conf.d/teleport-audit.conf"
  pipeline.ecs_compatibility: disabled

This disables the ECS for your Teleport audit log pipeline.

Run the Logstash pipeline

Restart Logstash:

sudo systemctl restart logstash

Make sure your Logstash pipeline started successfully by running the following command to tail Logstash's logs:

sudo journalctl -u logstash -f

When your Logstash pipeline initializes its http input and starts running, you should see a log similar to this:

Sep 15 18:27:13 myhost logstash[289107]: [2022-09-15T18:27:13,491][INFO ][logstash.inputs.http][main][33bdff0416b6a2b643e6f4ab3381a90c62b3aa05017770f4eb9416d797681024] Starting http input listener {:address=>"0.0.0.0:9601", :ssl=>"true"}

These logs indicate that your Logstash pipeline has connected to Elasticsearch and installed a new index template:

Sep 12 19:49:06 myhost logstash[33762]: [2022-09-12T19:49:06,309][INFO ][logstash.outputs.elasticsearch][main] Elasticsearch version determined (8.4.1) {:es_version=>8}
Sep 12 19:50:00 myhost logstash[33762]: [2022-09-12T19:50:00,993][INFO ][logstash.outputs.elasticsearch][main] Installing Elasticsearch template {:name=>"audit-events"}

Sep 12 19:43:04 myhost logstash[33762]: [2022-09-12T19:43:04,519][WARN ][logstash.outputs.elasticsearch][main] Attempted to resurrect connection to dead ES instance, but got an error {:url=>"http://teleport:[email protected]:9200/", :exception=>LogStash::Outputs::ElasticSearch::HttpClient::Pool::HostUnreachableError, :message=>"Elasticsearch Unreachable: [http://127.0.0.1:9200/][Manticore::ClientProtocolException] 127.0.0.1:9200 failed to respond"}

Sep 12 18:15:52 myhost logstash[27906]: [2022-09-12T18:15:52,146][INFO][logstash.javapipeline][main] Starting pipeline {:pipeline_id=>"main","pipeline.workers"=>2, "pipeline.batch.size"=>125, "pipeline.batch.delay"=>50,"pipeline.max_inflight"=>250,"pipeline.sources"=>["/etc/logstash/conf.d/teleport-audit.conf"],:thread=>"#<Thread:0x1c1a3ee5 run>"}
Sep 12 18:15:52 myhost logstash[27906]: [2022-09-12T18:15:52,912][INFO][logstash.javapipeline][main] Pipeline Java execution initialization time {"seconds"=>0.76}

Step 3/4. Run the Event Handler plugin

Complete the Event Handler configuration

Earlier, we generated a file called teleport-event-handler.toml to configure the Event Handler plugin. This file includes settings similar to the following:

storage = "./storage"
timeout = "10s"
batch = 20
namespace = "default"

[forward.fluentd]
ca = "/home/ca.crt"
cert = "/home/client.crt"
key = "/home/client.key"
url = "https://localhost:8888/test.log"

[teleport]
addr = "example.teleport.com:443"
identity = "identity"

Update the configuration file as follows.

Change forward.fluentd.url to the scheme, host and port you configured for your Logstash http input earlier, https://localhost:9601. Change forward.fluentd.session-url to the same value with the root URL path: https://localhost:9601/.

Change teleport.addr to the host and port of your Teleport Proxy Service, or the Auth Service if you have configured the Event Handler to connect to it directly, e.g., mytenant.teleport.sh:443.

Start the Event Handler

Start the Teleport Teleport Event Handler as a daemon. To do so, create a systemd service definition at the path /usr/lib/systemd/system/teleport-event-handler.service with the following content:

[Unit]
Description=Teleport Event Handler
After=network.target

[Service]
Type=simple
Restart=on-failure
ExecStart=/usr/local/bin/teleport-event-handler start --config=/etc/teleport-event-handler.toml
ExecReload=/bin/kill -HUP $MAINPID
PIDFile=/run/teleport-event-handler.pid

[Install]
WantedBy=multi-user.target

Enable and start the plugin:

sudo systemctl enable teleport-event-handler
sudo systemctl start teleport-event-handler

teleport-event-handler start --config teleport-event-handler.toml --start-time "2021-05-05T00:00:00Z"

Once the Teleport Event Handler starts, you will see notifications about scanned and forwarded events:

sudo journalctl -u teleport-event-handler
DEBU   Event sent id:f19cf375-4da6-4338-bfdc-e38334c60fd1 index:0 ts:2022-09-2118:51:04.849 +0000 UTC type:cert.create event-handler/app.go:140...

Step 4/4. Create a data view in Kibana

Make it possible to explore your Teleport audit events in Kibana by creating a data view. In the Elastic Stack UI, find the hamburger menu on the upper left of the screen, then click "Management" > "Data Views". Click "Create data view".

For the "Name" field, use "Teleport Audit Events". In "Index pattern", use audit-events-* to select all indices created by our Logstash pipeline. In "Timestamp field", choose time, which Teleport adds to its audit events.

To use your data view, find the search box at the top of the Elastic Stack UI and enter "Discover". On the upper left of the screen, click the dropdown menu and select "Teleport Audit Events". You can now search and filter your Teleport audit events in order to get a better understanding how users are interacting with your Teleport cluster.

For example, we can click the event field on the left sidebar and visualize the event types for your Teleport audit events over time:

Troubleshooting connection issues

If the Teleport Event Handler is displaying error logs while connecting to your Teleport Cluster, ensure that:

• The certificate the Teleport Event Handler is using to connect to your Teleport cluster is not past its expiration date. This is the value of the --ttl flag in the tctl auth sign command, which is 12 hours by default.
• Ensure that in your Teleport Event Handler configuration file (teleport-event-handler.toml), you have provided the correct host and port for the Teleport Proxy Service or Auth Service.

Next steps

Now that you are exporting your audit events to the Elastic Stack, consult our audit event reference so you can plan visualizations and alerts.

While this guide uses the tctl auth sign command to issue credentials for the Teleport Event Handler, production clusters should use Machine ID for safer, more reliable renewals. Read our guide to getting started with Machine ID.