> For the complete documentation index, see [llms.txt](https://docs.fortifiedid.se/access/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fortifiedid.se/access/key-components/authenticators/credential-validators/header-based/certificate.md).

# Certificate

This authenticator expects a configured HTTP header containing a X509 Certificate formatted as PEM.

## Configuration

{% hint style="info" %}
**Authenticator type:** `CertificateAuth`
{% endhint %}

Common Authenticator configuration can be found [here](/access/key-components/authenticators/common-configuration.md).

{% tabs %}
{% tab title="Properties" %}

<table data-full-width="true"><thead><tr><th>Name</th><th>Description</th><th>Default value</th><th data-type="checkbox">Mandatory</th></tr></thead><tbody><tr><td><code>certificate_header_name</code></td><td>Name of the headers containing the certificate.</td><td>N/A</td><td>true</td></tr><tr><td><code>missing_certificate_location</code></td><td>If the header contains no datat, where to redirect the client.</td><td>N/A</td><td>true</td></tr><tr><td><code>custom_identifier</code></td><td>When logging events, the custom_identifier lets you tag the event.</td><td>N/A</td><td>false</td></tr></tbody></table>
{% endtab %}

{% tab title="Example" %}

```json
{
            "id": "cert",
            "type": "CertificateAuth",
            "config": {
              "base_path": "/saml/authn",
              "certificate_header_name": "pemdata",
              "missing_certificate_location":"https://<custom_location>"
            }
}
```

{% endtab %}
{% endtabs %}

{% hint style="warning" %}
Property *base\_path* should not contain the full path when used in conjunction with the [Selector](/access/key-components/authenticators/flow-control/selector.md), instead, the full URI will be handled by the selector. The full path will be *base\_path + / + id*.
{% endhint %}

## Logging

Apart from system logging, event logging is done when starting, completing, and failing a transaction.

Event ids are:

* WEB\_100013("Authentication using certificate completed")
  * IDENTIFIER (user trace id)
  * SOURCE\_ADDRESS (ip address of device starting transaction)
  * CUSTOMER\_IDENTIFIER (if configured)
  * SOURCE\_USER\_NAME (subject from the certificate)
  * MESSAGE (certificate serial)

## Data exposed to global state

After a user completes a transaction, the authenticator is marked as done. Data from the authentication response is then put into the global state replacing existing values:

* serial
* subject
* certificate

## API

This authenticator has no UI


---

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