# Logging Amazon KMS API calls with Amazon CloudTrail
<a name="logging-using-cloudtrail"></a>

Amazon KMS is integrated with [Amazon CloudTrail](https://docs.amazonaws.cn/awscloudtrail/latest/userguide/), a service that records all calls to Amazon KMS by users, roles, and other Amazon services. CloudTrail captures all API calls to Amazon KMS as events, including calls from the Amazon KMS console, Amazon KMS APIs, Amazon CloudFormation templates, the Amazon Command Line Interface (Amazon CLI), and Amazon Tools for PowerShell.

CloudTrail logs all Amazon KMS operations, including read-only operations, such as [ListAliases](ct-listaliases.md) and [GetKeyRotationStatus](ct-getkeyrotationstatus.md), operations that manage KMS keys, such as [CreateKey](ct-createkey.md) and [PutKeyPolicy](ct-put-key-policy.md), and [cryptographic operations](kms-cryptography.md#cryptographic-operations), such as [GenerateDataKey](ct-generatedatakey.md) and [Decrypt](ct-decrypt.md). It also logs internal operations that Amazon KMS calls for you, such as [DeleteExpiredKeyMaterial](ct-deleteexpiredkeymaterial.md), [DeleteKey](ct-delete-key.md), [SynchronizeMultiRegionKey](ct-synchronize-multi-region-key.md), and [RotateKey](ct-rotatekey.md).

CloudTrail logs all successful operations and, in some scenarios, attempted calls that failed, such as when the caller is denied access to a resource. [Cross-account operations on KMS keys](key-policy-modifying-external-accounts.md) are logged in both the caller account and the KMS key owner account. However, cross-account Amazon KMS requests that are rejected because access is denied are logged only in the caller's account.

For security reasons, some fields are omitted from Amazon KMS log entries, such as the `Plaintext` parameter of an [Encrypt](https://docs.amazonaws.cn/kms/latest/APIReference/API_Encrypt.html) request, and the response to [GetKeyPolicy](https://docs.amazonaws.cn/kms/latest/APIReference/API_GetKeyPolicy.html) or any cryptographic operation. To make it easier to search for CloudTrail log entries for particular KMS keys, Amazon KMS adds the [key ARN](concepts.md#key-id-key-ARN) of the affected KMS key to the `responseElements` field in the log entries for some Amazon KMS key management operations, even when the API operation doesn't return the key ARN.

Although by default, all Amazon KMS actions are logged as CloudTrail events, you can exclude Amazon KMS actions from a CloudTrail trail. For details, see [Excluding Amazon KMS events from a trail](#filtering-kms-events).

**Learn more**: 
+ For CloudTrail log examples of Amazon KMS operations for attested platforms, see [Monitoring attested requests](ct-attestation.md).

**Topics**
+ [Finding Amazon KMS log entries in CloudTrail](#searching-kms-ct)
+ [Excluding Amazon KMS events from a trail](#filtering-kms-events)
+ [Examples of Amazon KMS log entries](understanding-kms-entries.md)

## Finding Amazon KMS log entries in CloudTrail
<a name="searching-kms-ct"></a>

To search CloudTrail log entries, use the [CloudTrail console](https://docs.aws.amazon.com/awscloudtrail/latest/userguide/view-cloudtrail-events-console.html) or the [CloudTrail LookupEvents](https://docs.aws.amazon.com/awscloudtrail/latest/APIReference/API_LookupEvents.html) operation. CloudTrail supports numerous [attribute values](https://docs.aws.amazon.com/awscloudtrail/latest/userguide/view-cloudtrail-events-console.html#filtering-cloudtrail-events) for filtering your search, including event name, user name, and event source. 

To help you search for Amazon KMS log entries in CloudTrail, Amazon KMS populates the following CloudTrail log entry fields.

**Note**  
Beginning in December 2022, Amazon KMS populates the **Resource type** and **Resource name** attributes in all management operations that change a particular KMS key. These attribute values might be null in older CloudTrail entries for the following operations: [CreateAlias](https://docs.amazonaws.cn/kms/latest/APIReference/API_CreateAlias.html), [CreateGrant](https://docs.amazonaws.cn/kms/latest/APIReference/API_CreateGrant.html), [DeleteAlias](https://docs.amazonaws.cn/kms/latest/APIReference/API_DeleteAlias.html), [DeleteImportedKeyMaterial](https://docs.amazonaws.cn/kms/latest/APIReference/API_DeleteImportedKeyMaterial.html), [ImportKeyMaterial](https://docs.amazonaws.cn/kms/latest/APIReference/API_ImportKeyMaterial.html), [ReplicateKey](https://docs.amazonaws.cn/kms/latest/APIReference/API_ReplicateKey.html), [RetireGrant](https://docs.amazonaws.cn/kms/latest/APIReference/API_RetireGrant.html), [RevokeGrant](https://docs.amazonaws.cn/kms/latest/APIReference/API_RevokeGrant.html), [UpdateAlias](https://docs.amazonaws.cn/kms/latest/APIReference/API_UpdateAlias.html), and [UpdatePrimaryRegion](https://docs.amazonaws.cn/kms/latest/APIReference/API_UpdatePrimaryRegion.html).


| Attribute | Value | Log entries | 
| --- | --- | --- | 
| Event source (EventSource) | kms.amazonaws.com | All operations. | 
| Resource type (ResourceType) | AWS::KMS::Key | Management operations that change a particular KMS key, such as CreateKey and EnableKey, but not ListKeys. | 
| Resource name (ResourceName) | Key ARN (or key ID and key ARN) | Management operations that change a particular KMS key, such as CreateKey and EnableKey, but not ListKeys. | 

To help you find log entries for management operations on particular KMS keys, Amazon KMS records the key ARN of the affected KMS key in the `responseElements.keyId` element of the log entry, even when the Amazon KMS API operation doesn't return the key ARN.

For example, a successful call to the [DisableKey](https://docs.amazonaws.cn/kms/latest/APIReference/API_DisableKey.html) operation doesn't return any values in the response, but instead of a null value, the `responseElements.keyId` value in the [DisableKey log entry](ct-disablekey.md) includes the key ARN of the disabled KMS key.

This feature was added in December 2022 and affects the following CloudTrail log entries: [CreateAlias](ct-createalias.md), [CreateGrant](ct-creategrant.md), [DeleteAlias](ct-deletealias.md), [DeleteKey](ct-delete-key.md), [DisableKey](ct-disablekey.md), [EnableKey](ct-enablekey.md), [EnableKeyRotation](ct-enablekeyrotation.md), [ImportKeyMaterial](ct-importkeymaterial.md), [RotateKey](ct-rotatekey.md), [SynchronizeMultiRegionKey](ct-synchronize-multi-region-key.md), [TagResource](ct-tagresource.md), [UntagResource](ct-untagresource.md), [UpdateAlias](ct-updatealias.md), and [UpdatePrimaryRegion](ct-update-primary-region.md).

## Excluding Amazon KMS events from a trail
<a name="filtering-kms-events"></a>

To provide a record of the use and management of their Amazon KMS resources, most Amazon KMS users rely on the events in a CloudTrail trail. The trail can be an valuable source of data for auditing critical events, such as creating, disabling, and deleting Amazon KMS keys, changing key policy, and the use of your KMS keys by Amazon services on your behalf. In some cases, the metadata in a CloudTrail log entry, such as the [encryption context](encrypt_context.md) in an encryption operation, can help you to avoid or resolve errors.

However, because Amazon KMS can generate a large number of events, Amazon CloudTrail lets you exclude Amazon KMS events from a trail. This per-trail setting excludes all Amazon KMS events; you cannot exclude particular Amazon KMS events.

**Warning**  
Excluding Amazon KMS events from a CloudTrail Log can obscure actions that use your KMS keys. Be cautious when giving principals the `cloudtrail:PutEventSelectors` permission that is required to perform this operation.

To exclude Amazon KMS events from a trail: 
+ In the CloudTrail console, use the **Log Key Management Service events** setting when you [create a trail](https://docs.amazonaws.cn/awscloudtrail/latest/userguide/cloudtrail-create-a-trail-using-the-console-first-time.html) or [update a trail](https://docs.amazonaws.cn/awscloudtrail/latest/userguide/cloudtrail-update-a-trail-console.html). For instructions, see [Logging Management Events with the Amazon Web Services Management Console](https://docs.amazonaws.cn/awscloudtrail/latest/userguide/logging-management-and-data-events-with-cloudtrail.html) in the Amazon CloudTrail User Guide.
+ In the CloudTrail API, use the [PutEventSelectors](https://docs.amazonaws.cn/awscloudtrail/latest/APIReference/API_PutEventSelectors.html) operation. Add the `ExcludeManagementEventSources` attribute to your event selectors with a value of `kms.amazonaws.com`. For an example, see [Example: A trail that does not log Amazon Key Management Service events](https://docs.amazonaws.cn/awscloudtrail/latest/userguide/cloudtrail-additional-cli-commands.html#configuring-event-selector-example-kms) in the Amazon CloudTrail User Guide.

You can disable this exclusion at any time by changing the console setting or the event selectors for a trail. The trail will then start recording Amazon KMS events. However, it cannot recover Amazon KMS events that occurred while the exclusion was effective.

When you exclude Amazon KMS events by using the console or API, the resulting CloudTrail `PutEventSelectors` API operation is also logged in your CloudTrail Logs. If Amazon KMS events don't appear in your CloudTrail Logs, look for a `PutEventSelectors` event with the `ExcludeManagementEventSources` attribute set to `kms.amazonaws.com`.