KMS / Client / import_key_material

import_key_material#

KMS.Client.import_key_material(**kwargs)#

Imports or reimports key material into an existing KMS key that was created without key material. ImportKeyMaterial also sets the expiration model and expiration date of the imported key material.

By default, KMS keys are created with key material that KMS generates. This operation supports Importing key material, an advanced feature that lets you generate and import the cryptographic key material for a KMS key. For more information about importing key material into KMS, see Importing key material in the Key Management Service Developer Guide.

After you successfully import key material into a KMS key, you can reimport the same key material into that KMS key, but you cannot import different key material. You might reimport key material to replace key material that expired or key material that you deleted. You might also reimport key material to change the expiration model or expiration date of the key material.

Each time you import key material into KMS, you can determine whether ( ExpirationModel) and when ( ValidTo) the key material expires. To change the expiration of your key material, you must import it again, either by calling ImportKeyMaterial or using the import features of the KMS console.

Before calling ImportKeyMaterial:

  • Create or identify a KMS key with no key material. The KMS key must have an Origin value of EXTERNAL, which indicates that the KMS key is designed for imported key material. To create an new KMS key for imported key material, call the CreateKey operation with an Origin value of EXTERNAL. You can create a symmetric encryption KMS key, HMAC KMS key, asymmetric encryption KMS key, or asymmetric signing KMS key. You can also import key material into a multi-Region key of any supported type. However, you can’t import key material into a KMS key in a custom key store.

  • Use the DescribeKey operation to verify that the KeyState of the KMS key is PendingImport, which indicates that the KMS key has no key material. If you are reimporting the same key material into an existing KMS key, you might need to call the DeleteImportedKeyMaterial to delete its existing key material.

  • Call the GetParametersForImport operation to get a public key and import token set for importing key material.

  • Use the public key in the GetParametersForImport response to encrypt your key material.

Then, in an ImportKeyMaterial request, you submit your encrypted key material and import token. When calling this operation, you must specify the following values:

  • The key ID or key ARN of the KMS key to associate with the imported key material. Its Origin must be EXTERNAL and its KeyState must be PendingImport. You cannot perform this operation on a KMS key in a custom key store, or on a KMS key in a different Amazon Web Services account. To get the Origin and KeyState of a KMS key, call DescribeKey.

  • The encrypted key material.

  • The import token that GetParametersForImport returned. You must use a public key and token from the same GetParametersForImport response.

  • Whether the key material expires ( ExpirationModel) and, if so, when ( ValidTo). For help with this choice, see Setting an expiration time in the Key Management Service Developer Guide. If you set an expiration date, KMS deletes the key material from the KMS key on the specified date, making the KMS key unusable. To use the KMS key in cryptographic operations again, you must reimport the same key material. However, you can delete and reimport the key material at any time, including before the key material expires. Each time you reimport, you can eliminate or reset the expiration time.

When this operation is successful, the key state of the KMS key changes from PendingImport to Enabled, and you can use the KMS key in cryptographic operations.

If this operation fails, use the exception to help determine the problem. If the error is related to the key material, the import token, or wrapping key, use GetParametersForImport to get a new public key and import token for the KMS key and repeat the import procedure. For help, see How To Import Key Material in the Key Management Service Developer Guide.

The KMS key that you use for this operation must be in a compatible key state. For details, see Key states of KMS keys in the Key Management Service Developer Guide.

Cross-account use: No. You cannot perform this operation on a KMS key in a different Amazon Web Services account.

Required permissions: kms:ImportKeyMaterial (key policy)

Related operations:

  • DeleteImportedKeyMaterial

  • GetParametersForImport

Eventual consistency: The KMS API follows an eventual consistency model. For more information, see KMS eventual consistency.

See also: AWS API Documentation

Request Syntax

response = client.import_key_material(
    KeyId='string',
    ImportToken=b'bytes',
    EncryptedKeyMaterial=b'bytes',
    ValidTo=datetime(2015, 1, 1),
    ExpirationModel='KEY_MATERIAL_EXPIRES'|'KEY_MATERIAL_DOES_NOT_EXPIRE'
)
Parameters:

  • KeyId (string) –

    [REQUIRED]

    The identifier of the KMS key that will be associated with the imported key material. This must be the same KMS key specified in the KeyID parameter of the corresponding GetParametersForImport request. The Origin of the KMS key must be EXTERNAL and its KeyState must be PendingImport.

    The KMS key can be a symmetric encryption KMS key, HMAC KMS key, asymmetric encryption KMS key, or asymmetric signing KMS key, including a multi-Region key of any supported type. You cannot perform this operation on a KMS key in a custom key store, or on a KMS key in a different Amazon Web Services account.

    Specify the key ID or key ARN of the KMS key.

    For example:

    • Key ID: 1234abcd-12ab-34cd-56ef-1234567890ab

    • Key ARN: arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab

    To get the key ID and key ARN for a KMS key, use ListKeys or DescribeKey.

  • ImportToken (bytes) –

    [REQUIRED]

    The import token that you received in the response to a previous GetParametersForImport request. It must be from the same response that contained the public key that you used to encrypt the key material.

  • EncryptedKeyMaterial (bytes) –

    [REQUIRED]

    The encrypted key material to import. The key material must be encrypted under the public wrapping key that GetParametersForImport returned, using the wrapping algorithm that you specified in the same GetParametersForImport request.

  • ValidTo (datetime) –

    The date and time when the imported key material expires. This parameter is required when the value of the ExpirationModel parameter is KEY_MATERIAL_EXPIRES. Otherwise it is not valid.

    The value of this parameter must be a future date and time. The maximum value is 365 days from the request date.

    When the key material expires, KMS deletes the key material from the KMS key. Without its key material, the KMS key is unusable. To use the KMS key in cryptographic operations, you must reimport the same key material.

    You cannot change the ExpirationModel or ValidTo values for the current import after the request completes. To change either value, you must delete ( DeleteImportedKeyMaterial) and reimport the key material.

  • ExpirationModel (string) –

    Specifies whether the key material expires. The default is KEY_MATERIAL_EXPIRES. For help with this choice, see Setting an expiration time in the Key Management Service Developer Guide.

    When the value of ExpirationModel is KEY_MATERIAL_EXPIRES, you must specify a value for the ValidTo parameter. When value is KEY_MATERIAL_DOES_NOT_EXPIRE, you must omit the ValidTo parameter.

    You cannot change the ExpirationModel or ValidTo values for the current import after the request completes. To change either value, you must reimport the key material.

Return type:

dict

Returns:

Response Syntax

{}

Response Structure

  • (dict) –

Exceptions

Examples

The following example imports key material into the specified KMS key.

response = client.import_key_material(
    # The encrypted key material to import.
    EncryptedKeyMaterial='<binary data>',
    # A value that specifies whether the key material expires.
    ExpirationModel='KEY_MATERIAL_DOES_NOT_EXPIRE',
    # The import token that you received in the response to a previous GetParametersForImport request.
    ImportToken='<binary data>',
    # The identifier of the KMS key to import the key material into. You can use the key ID or the Amazon Resource Name (ARN) of the KMS key.
    KeyId='1234abcd-12ab-34cd-56ef-1234567890ab',
)

print(response)

Expected Output:

{
    'ResponseMetadata': {
        '...': '...',
    },
}