Encrypting your Data Catalog
AWS Glue Data Catalog encryption provides enhanced security for your sensitive data. AWS Glue integrates with AWS Key Management Service (AWS KMS) to encrypt metadata that's stored in the Data Catalog, including automatically registered assets that you enrich with business context for semantic search. You can enable or disable encryption settings for resources in the Data Catalog using the AWS Glue console or the AWS CLI.
When you enable encryption for your Data Catalog, all new objects that you create will be encrypted. When you disable encryption, the new objects you create will not be encrypted, but existing encrypted objects will remain encrypted.
You can encrypt your entire Data Catalog using AWS managed encryption keys or customer managed encryption keys. For more information on key types and states, see AWS Key Management Service concepts in the AWS Key Management Service Developer Guide.
Note
When you use the encrypted Data Catalog with a crawler, you must maintain the encryption settings. Removing encryption settings after a crawler has processed an encrypted catalog results in errors. If you need to remove encryption settings, create a new crawler instead of modifying the existing one.
AWS managed keys
AWS managed keys are KMS keys in your account that are created, managed, and used on your behalf by an AWS service that's integrated with AWS KMS. You can view the AWS managed keys in your account, view their key policies, and audit their use in AWS CloudTrail logs. However, you can't manage these keys or change their permissions.
Encryption at rest automatically integrates with AWS KMS for managing the AWS managed keys for AWS Glue that are used to encrypt your metadata. If an AWS managed key doesn't exist when you enable metadata encryption, AWS KMS automatically creates a new key for you.
For more information, see AWS managed keys.
Customer managed keys
Customer managed keys are KMS keys in your AWS account that you create, own, and manage. You have full control over these KMS keys. You can:
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Establish and maintain their key policies, IAM policies, and grants
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Enable and disable them
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Rotate their cryptographic material
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Add tags
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Create aliases that refer to them
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Schedule them for deletion
For more information about managing the permissions of a customer managed key, see Customer managed keys.
Important
AWS Glue supports only symmetric customer managed keys. The KMS key list displays only symmetric keys. However, if you select Choose a KMS key ARN, the console lets you enter an ARN for any key type. Ensure that you enter only ARNs for symmetric keys.
To create a symmetric customer managed key, follow the steps for creating symmetric customer managed keys in the AWS Key Management Service Developer Guide.
When you enable Data Catalog encryption at rest, the following resource types are encrypted using KMS keys:
Databases
Tables
Partitions
Table versions
Column statistics
User-defined functions
Data Catalog views
Catalog assets
AWS Glue encryption context
An encryption context
is an optional set of key-value pairs that contain additional contextual information about the data.
AWS KMS uses the encryption context as additional authenticated data to support authenticated encryption.
When you include an encryption context in a request to encrypt data, AWS KMS binds the encryption context to the encrypted data.
To decrypt data, you include the same encryption context in the request.
AWS Glue uses the same encryption context in all AWS KMS cryptographic operations, where the key is glue_catalog_id and the value is the catalogId.
"encryptionContext": { "glue_catalog_id": "111122223333" }
When you use an AWS managed key or a symmetric customer managed key to encrypt your Data Catalog, you can also use the encryption context in audit records and logs to identify how the key is being used. The encryption context also appears in logs that are generated by AWS CloudTrail or Amazon CloudWatch logs.
Enabling encryption
You can enable encryption for your AWS Glue Data Catalog objects in the Data Catalog settings in the AWS Glue console or by using the AWS CLI.
When you enable encryption, all objects that you create in the Data Catalog objects are encrypted. If you clear this setting, the objects you create in the Data Catalog are no longer encrypted. You can continue to access the existing encrypted objects in the Data Catalog with the required KMS permissions.
ImportantThe AWS KMS key must remain available in the AWS KMS key store for any objects that are encrypted with it in the Data Catalog. If you remove the key, the objects can no longer be decrypted. You might want this in some scenarios to prevent access to Data Catalog metadata. |
Encrypting Catalog assets with AWS KMS customer managed key
Supported catalog resources are automatically registered in your AWS Glue Data Catalog as assets. You add business context to these assets, which enables you to semantically search and filter on this metadata in AWS Glue. When you enable metadata encryption with a customer managed key, AWS Glue also encrypts the search index for your Data Catalog with your KMS key. No additional steps are required — AWS Glue enables search index encryption automatically as part of metadata encryption.
If you previously enabled Data Catalog encryption with a customer managed key and
your existing policy includes only kms:Decrypt,
kms:Encrypt, and kms:GenerateDataKey, you must add the
following permissions to support catalog assets and semantic search:
kms:DescribeKey— required for key validation.kms:CreateGrant— allows AWS Glue to encrypt and re-encrypt the search index in the background. AWS Glue scopes the grant to theglue_catalog_idencryption context.
For the full policy that includes these permissions, see Enabling encryption. If you are setting up encryption for the first time, the policy in that section already includes all required permissions.
Important
Semantic search over Data Catalog assets does not support the AWS managed key
(aws/glue). If your Data Catalog metadata is encrypted with
aws/glue, search over that catalog is not available until you change
the configuration to use a customer managed key or remove the configuration.
Enabling metadata encryption is an asynchronous operation. AWS Glue accepts your
request and then completes the encryption setup, including encryption of the existing
search index. Enabling encryption for the first time could take some time depending
on the size of your Data Catalog. During this time, the business context and search APIs
return an error until the status is Enabled.
The following table describes the different encryption statuses for the Data Catalog asset metadata:
| Status | Description |
|---|---|
Enabling |
AWS Glue is setting up encryption. When you enable encryption for the first time, search is not available until setup completes. When you change from one customer managed key to another, search remains available. |
Enabled |
Encryption is complete. Your Data Catalog metadata is searchable. |
Enabled (with errors) |
Encryption is complete, and search is available, but AWS Glue could not process some metadata. The console displays the error messages. To retry the failed items, save your encryption settings again after fixing the errors. |
Failed |
Encryption could not be completed, and search is not available. Review the error message, correct the configuration, and save your encryption settings again with a customer managed key. |
Disabling |
AWS Glue is disabling encryption from the search index with your KMS key. |
Disabled |
Your Data Catalog metadata and search index are no longer encrypted with your KMS key. Business context and search APIs continue to work. |
When you change your Data Catalog encryption from one customer managed key to
another, AWS Glue re-encrypts the search index with the new key. Search remains
available while re-encryption is in progress. When you disable metadata
encryption, AWS Glue removes your KMS key from the search index and the status
changes to Disabled.
Warning
Do not disable, delete, or revoke access to the previous KMS key until the
encryption status returns to Enabled (or Disabled,
if you disabled encryption). If AWS Glue loses access to the previous key
before the operation completes, it cannot decrypt the search index, the
status changes to Failed, and search over your Data Catalog is
not available.
The principal that enables or changes metadata encryption must have the
kms:CreateGrant permission described in Enabling encryption. AWS Glue uses the
glue_catalog_id encryption context (the value is your
catalogId) in AWS KMS operations for the search index, consistent with
AWS Glue encryption context. The AWS KMS
calls that AWS Glue makes for the search index are recorded in AWS CloudTrail.
The principal that accesses business context and search must also have access to the KMS key. If you have delegated AWS KMS operations to an IAM service role, the service role must have access to the KMS key instead.
In addition to the identity policy, you must also add the following statement to
your KMS key policy to allow AWS Glue to create grants for search index encryption.
The kms:GrantIsForAWSResource condition limits the grant to AWS Glue, and
the glue_catalog_id encryption context scopes it to your Data Catalog. To
use the statement, replace the user input placeholders
with your own information.
{ "Sid": "AllowCreateGrantForSearchIndexEncryption", "Effect": "Allow", "Principal": { "AWS": "arn:aws:iam::account-id:root" }, "Action": "kms:CreateGrant", "Resource": "arn:aws:kms:region:account-id:key/key-id", "Condition": { "StringLike": { "kms:CallerAccount": "account-id" }, "Bool": { "kms:GrantIsForAWSResource": "true" }, "StringEquals": { "kms:EncryptionContext:glue_catalog_id": "account-id" } } }
Monitoring your KMS keys for AWS Glue
When you use KMS keys with your Data Catalog resources, you can use AWS CloudTrail or Amazon CloudWatch Logs to track requests that AWS Glue sends to AWS KMS. AWS CloudTrail monitors and records KMS operations that AWS Glue calls to access data that’s encrypted by your KMS keys.
The following examples are AWS CloudTrail events for the
Decrypt, GenerateDataKey,
CreateGrant, and RetireGrant operations. When you
enable encryption with a customer managed key, AWS Glue creates a AWS KMS grant
scoped to the glue_catalog_id encryption context so that it can
encrypt and re-encrypt Data Catalog metadata in the background, and retires the
grant when AWS Glue no longer needs it.