DescribeKey
Provides detailed information about a customer master key (CMK). You can run
DescribeKey
on a customer managed CMK or an AWS managed
CMK.
This detailed information includes the key ARN, creation date (and deletion date,
if
applicable), the key state, and the origin and expiration date (if any) of the key
material.
For CMKs in custom key stores, it includes information about the custom key store,
such as the
key store ID and the AWS CloudHSM cluster ID. It includes fields, like KeySpec
, that
help you distinguish symmetric from asymmetric CMKs. It also provides information
that is
particularly important to asymmetric CMKs, such as the key usage (encryption or signing)
and
the encryption algorithms or signing algorithms that the CMK supports.
DescribeKey
does not return the following information:
-
Aliases associated with the CMK. To get this information, use ListAliases.
-
Whether automatic key rotation is enabled on the CMK. To get this information, use GetKeyRotationStatus. Also, some key states prevent a CMK from being automatically rotated. For details, see How Automatic Key Rotation Works in AWS Key Management Service Developer Guide.
-
Tags on the CMK. To get this information, use ListResourceTags.
-
Key policies and grants on the CMK. To get this information, use GetKeyPolicy and ListGrants.
If you call the DescribeKey
operation on a predefined AWS
alias, that is, an AWS alias with no key ID, AWS KMS creates an AWS managed CMK.
Then, it associates the alias with the new CMK, and returns the KeyId
and
Arn
of the new CMK in the response.
Cross-account use: Yes. To perform this operation with a CMK in a different AWS account, specify
the key ARN or alias ARN in the value of the KeyId
parameter.
Required permissions: kms:DescribeKey (key policy)
Related operations:
Request Syntax
{
"GrantTokens": [ "string
" ],
"KeyId": "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.
In the following list, the required parameters are described first.
- KeyId
-
Describes the specified customer master key (CMK).
If you specify a predefined AWS alias (an AWS alias with no key ID), KMS associates the alias with an AWS managed CMK and returns its
KeyId
andArn
in the response.To specify a CMK, use its key ID, Amazon Resource Name (ARN), alias name, or alias ARN. When using an alias name, prefix it with
"alias/"
. To specify a CMK in a different AWS account, you must use the key ARN or alias ARN.For example:
-
Key ID:
1234abcd-12ab-34cd-56ef-1234567890ab
-
Key ARN:
arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab
-
Alias name:
alias/ExampleAlias
-
Alias ARN:
arn:aws:kms:us-east-2:111122223333:alias/ExampleAlias
To get the key ID and key ARN for a CMK, use ListKeys or DescribeKey. To get the alias name and alias ARN, use ListAliases.
Type: String
Length Constraints: Minimum length of 1. Maximum length of 2048.
Required: Yes
-
- GrantTokens
-
A list of grant tokens.
Use a grant token when your permission to call this operation comes from a new grant that has not yet achieved eventual consistency. For more information, see Grant token and Using a grant token in the AWS Key Management Service Developer Guide.
Type: Array of strings
Array Members: Minimum number of 0 items. Maximum number of 10 items.
Length Constraints: Minimum length of 1. Maximum length of 8192.
Required: No
Response Syntax
{
"KeyMetadata": {
"Arn": "string",
"AWSAccountId": "string",
"CloudHsmClusterId": "string",
"CreationDate": number,
"CustomerMasterKeySpec": "string",
"CustomKeyStoreId": "string",
"DeletionDate": number,
"Description": "string",
"Enabled": boolean,
"EncryptionAlgorithms": [ "string" ],
"ExpirationModel": "string",
"KeyId": "string",
"KeyManager": "string",
"KeyState": "string",
"KeyUsage": "string",
"Origin": "string",
"SigningAlgorithms": [ "string" ],
"ValidTo": number
}
}
Response Elements
If the action is successful, the service sends back an HTTP 200 response.
The following data is returned in JSON format by the service.
- KeyMetadata
-
Metadata associated with the key.
Type: KeyMetadata object
Errors
For information about the errors that are common to all actions, see Common Errors.
- DependencyTimeoutException
-
The system timed out while trying to fulfill the request. The request can be retried.
HTTP Status Code: 500
- InvalidArnException
-
The request was rejected because a specified ARN, or an ARN in a key policy, 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
- NotFoundException
-
The request was rejected because the specified entity or resource could not be found.
HTTP Status Code: 400
Examples
The following examples are formatted for legibility.
Example Request
This example illustrates one usage of DescribeKey.
POST / HTTP/1.1 Host: kms.us-east-2.amazonaws.com Content-Length: 49 X-Amz-Target: TrentService.DescribeKey X-Amz-Date: 20170705T211529Z Authorization: AWS4-HMAC-SHA256\ Credential=AKIAI44QH8DHBEXAMPLE/20170705/us-east-2/kms/aws4_request,\ SignedHeaders=content-type;host;x-amz-date;x-amz-target,\ Signature=6bcb6a5ef9ee7585d83955e8a5c3f6d47cf581596208fc0e436fa1de26ef3f6a Content-Type: application/x-amz-json-1.1 {"KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab"}
Example Response
This example illustrates one usage of DescribeKey.
HTTP/1.1 200 OK Server: Server Date: Wed, 05 Jul 2017 21:15:30 GMT Content-Type: application/x-amz-json-1.1 Content-Length: 335 Connection: keep-alive x-amzn-RequestId: 13230ddb-61c7-11e7-af6f-c5b105d7a982 { "KeyMetadata": { "AWSAccountId": "111122223333", "Arn": "arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab", "CreationDate": 1.499288695918E9, "Description": "", "Enabled": true, "KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab", "KeyManager": "CUSTOMER", "KeyState": "Enabled", "KeyUsage": "ENCRYPT_DECRYPT", "Origin": "AWS_KMS" "CustomerMasterKeySpec": "SYMMETRIC_DEFAULT", "EncryptionAlgorithms": [ "SYMMETRIC_DEFAULT" ] } }
See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following: