Request Syntax Request Parameters Response Elements Errors Examples See Also

CreateAlias

Creates a friendly name for a KMS key.

Note

Adding, deleting, or updating an alias can allow or deny permission to the KMS key. For details, see ABAC for Amazon KMS in the Amazon Key Management Service Developer Guide.

You can use an alias to identify a KMS key in the Amazon KMS console, in the DescribeKey operation and in cryptographic operations, such as Encrypt and GenerateDataKey. You can also change the KMS key that's associated with the alias (UpdateAlias) or delete the alias (DeleteAlias) at any time. These operations don't affect the underlying KMS key.

You can associate the alias with any customer managed key in the same Amazon Region. Each alias is associated with only one KMS key at a time, but a KMS key can have multiple aliases. A valid KMS key is required. You can't create an alias without a KMS key.

The alias must be unique in the account and Region, but you can have aliases with the same name in different Regions. For detailed information about aliases, see Aliases in Amazon KMS in the Amazon Key Management Service Developer Guide.

This operation does not return a response. To get the alias that you created, use the ListAliases operation.

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

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

Required permissions

kms:CreateAlias on the alias (IAM policy).
kms:CreateAlias on the KMS key (key policy).

For details, see Controlling access to aliases in the Amazon Key Management Service Developer Guide.

Related operations:

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

Request Syntax


{
   "AliasName": "string",
   "TargetKeyId": "string"
}

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.

Note

In the following list, the required parameters are described first.

AliasName

Specifies the alias name. This value must begin with alias/ followed by a name, such as alias/ExampleAlias.

Important

Do not include confidential or sensitive information in this field. This field may be displayed in plaintext in CloudTrail logs and other output.

The AliasName value must be string of 1-256 characters. It can contain only alphanumeric characters, forward slashes (/), underscores (_), and dashes (-). The alias name cannot begin with alias/aws/. The alias/aws/ prefix is reserved for Amazon managed keys.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 256.

Pattern: ^alias/[a-zA-Z0-9/_-]+$

Required: Yes

TargetKeyId

Associates the alias with the specified customer managed key. The KMS key must be in the same Amazon Region.

A valid key ID is required. If you supply a null or empty string value, this operation returns an error.

For help finding the key ID and ARN, see Find the key ID and key ARN in the Amazon Key Management Service Developer Guide .

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.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 2048.

Required: Yes

Response Elements

If the action is successful, the service sends back an HTTP 200 response with an empty HTTP body.

Errors

For information about the errors that are common to all actions, see Common Errors.

AlreadyExistsException

The request was rejected because it attempted to create a resource that already exists.

HTTP Status Code: 400

DependencyTimeoutException

The system timed out while trying to fulfill the request. You can retry the request.

HTTP Status Code: 500

InvalidAliasNameException

The request was rejected because the specified alias name is not valid.

HTTP Status Code: 400

KMSInternalException

The request was rejected because an internal exception occurred. The request can be retried.

HTTP Status Code: 500

KMSInvalidStateException

The request was rejected because the state of the specified resource is not valid for this request.

This exceptions means one of the following:

The key state of the KMS key is not compatible with the operation.

To find the key state, use the DescribeKey operation. For more information about which key states are compatible with each Amazon KMS operation, see Key states of Amazon KMS keys in the Amazon Key Management Service Developer Guide .
For cryptographic operations on KMS keys in custom key stores, this exception represents a general failure with many possible causes. To identify the cause, see the error message that accompanies the exception.

HTTP Status Code: 400

LimitExceededException

The request was rejected because a length constraint or quota was exceeded. For more information, see Quotas in the Amazon Key Management Service Developer Guide.

HTTP Status Code: 400

NotFoundException

The request was rejected because the specified entity or resource could not be found.

HTTP Status Code: 400

Examples

Example Request

The following example is formatted for legibility.


POST / HTTP/1.1
Host: kms.us-west-2.amazonaws.com
Content-Length: 87
X-Amz-Target: TrentService.CreateAlias
X-Amz-Date: 20160517T204220Z
Content-Type: application/x-amz-json-1.1
Authorization: AWS4-HMAC-SHA256\
 Credential=AKIAI44QH8DHBEXAMPLE/20160517/us-west-2/kms/aws4_request,\
 SignedHeaders=content-type;host;x-amz-date;x-amz-target,\
 Signature=ca7bcf1e8d5364dc3f0d881c05bdadf36f498c6c6a8b576a060142d9b2199123

{
  "TargetKeyId": "1234abcd-12ab-34cd-56ef-1234567890ab",
  "AliasName": "alias/ExampleAlias"
}

Example Response

This example illustrates one usage of CreateAlias.


HTTP/1.1 200 OK
Server: Server
Date: Tue, 17 May 2016 20:42:25 GMT
Content-Type: application/x-amz-json-1.1
Content-Length: 0
Connection: keep-alive
x-amzn-RequestId: dcb07ca7-1c6f-11e6-8540-77c363708b91