Returns a unique symmetric data key for use outside of KMS. This operation returns a data key that is encrypted under a symmetric encryption KMS key that you specify. The bytes in the key are random; they are not related to the caller or to the KMS key.
GenerateDataKeyWithoutPlaintext
is identical to the GenerateDataKey operation except that it does not return a plaintext copy of the data key.
This operation is useful for systems that need to encrypt data at some point, but not immediately. When you need to encrypt the data, you call the Decrypt operation on the encrypted copy of the key.
It’s also useful in distributed systems with different levels of trust. For example, you might store encrypted data in containers. One component of your system creates new containers and stores an encrypted data key with each container. Then, a different component puts the data into the containers. That component first decrypts the data key, uses the plaintext data key to encrypt data, puts the encrypted data into the container, and then destroys the plaintext data key. In this system, the component that creates the containers never sees the plaintext data key.
To request an asymmetric data key pair, use the GenerateDataKeyPair or GenerateDataKeyPairWithoutPlaintext operations.
To generate a data key, you must specify the symmetric encryption KMS key that is used to encrypt the data key. You cannot use an asymmetric KMS key or a key in a custom key store to generate a data key. To get the type of your KMS key, use the DescribeKey operation.
You must also specify the length of the data key. Use either the KeySpec
or NumberOfBytes
parameters (but not both). For 128-bit and 256-bit data keys, use the KeySpec
parameter.
To generate an SM4 data key (China Regions only), specify a KeySpec
value of AES_128
or NumberOfBytes
value of 16
. The symmetric encryption key used in China Regions to encrypt your data key is an SM4 encryption key.
If the operation succeeds, you will find the encrypted copy of the data key in the CiphertextBlob
field.
You can use an optional encryption context to add additional security to the encryption operation. If you specify an EncryptionContext
, you must specify the same encryption context (a case-sensitive exact match) when decrypting the encrypted data key. Otherwise, the request to decrypt fails with an InvalidCiphertextException
. For more information, see Encryption Context 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 : Yes. To perform this operation with a KMS key in a different Amazon Web Services account, specify the key ARN or alias ARN in the value of the
KeyId
parameter.Required permissions : kms:GenerateDataKeyWithoutPlaintext (key policy)
Related operations:
Eventual consistency : The KMS API follows an eventual consistency model. For more information, see KMS eventual consistency .
See also: AWS API Documentation
generate-data-key-without-plaintext
--key-id <value>
[--encryption-context <value>]
[--key-spec <value>]
[--number-of-bytes <value>]
[--grant-tokens <value>]
[--dry-run | --no-dry-run]
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]
[--debug]
[--endpoint-url <value>]
[--no-verify-ssl]
[--no-paginate]
[--output <value>]
[--query <value>]
[--profile <value>]
[--region <value>]
[--version <value>]
[--color <value>]
[--no-sign-request]
[--ca-bundle <value>]
[--cli-read-timeout <value>]
[--cli-connect-timeout <value>]
[--cli-binary-format <value>]
[--no-cli-pager]
[--cli-auto-prompt]
[--no-cli-auto-prompt]
--key-id
(string)
Specifies the symmetric encryption KMS key that encrypts the data key. You cannot specify an asymmetric KMS key or a KMS key in a custom key store. To get the type and origin of your KMS key, use the DescribeKey operation.
To specify a KMS key, use its key ID, key ARN, alias name, or alias ARN. When using an alias name, prefix it with
"alias/"
. To specify a KMS key in a different Amazon Web Services 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 KMS key, use ListKeys or DescribeKey . To get the alias name and alias ARN, use ListAliases .
--encryption-context
(map)
Specifies the encryption context that will be used when encrypting the data key.
Warning
Do not include confidential or sensitive information in this field. This field may be displayed in plaintext in CloudTrail logs and other output.An encryption context is a collection of non-secret key-value pairs that represent additional authenticated data. When you use an encryption context to encrypt data, you must specify the same (an exact case-sensitive match) encryption context to decrypt the data. An encryption context is supported only on operations with symmetric encryption KMS keys. On operations with symmetric encryption KMS keys, an encryption context is optional, but it is strongly recommended.
For more information, see Encryption context in the Key Management Service Developer Guide .
key -> (string)
value -> (string)
Shorthand Syntax:
KeyName1=string,KeyName2=string
JSON Syntax:
{"string": "string"
...}
--key-spec
(string)
The length of the data key. Use
AES_128
to generate a 128-bit symmetric key, orAES_256
to generate a 256-bit symmetric key.Possible values:
AES_256
AES_128
--number-of-bytes
(integer)
The length of the data key in bytes. For example, use the value 64 to generate a 512-bit data key (64 bytes is 512 bits). For common key lengths (128-bit and 256-bit symmetric keys), we recommend that you use theKeySpec
field instead of this one.
--grant-tokens
(list)
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 Key Management Service Developer Guide .
(string)
Syntax:
"string" "string" ...
--dry-run
| --no-dry-run
(boolean)
Checks if your request will succeed.
DryRun
is an optional parameter.To learn more about how to use this parameter, see Testing your KMS API calls in the Key Management Service Developer Guide .
--cli-input-json
| --cli-input-yaml
(string)
Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton
. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml
.
--generate-cli-skeleton
(string)
Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input
, prints a sample input JSON that can be used as an argument for --cli-input-json
. Similarly, if provided yaml-input
it will print a sample input YAML that can be used with --cli-input-yaml
. If provided with the value output
, it validates the command inputs and returns a sample output JSON for that command. The generated JSON skeleton is not stable between versions of the AWS CLI and there are no backwards compatibility guarantees in the JSON skeleton generated.
--debug
(boolean)
Turn on debug logging.
--endpoint-url
(string)
Override command’s default URL with the given URL.
--no-verify-ssl
(boolean)
By default, the AWS CLI uses SSL when communicating with AWS services. For each SSL connection, the AWS CLI will verify SSL certificates. This option overrides the default behavior of verifying SSL certificates.
--no-paginate
(boolean)
Disable automatic pagination. If automatic pagination is disabled, the AWS CLI will only make one call, for the first page of results.
--output
(string)
The formatting style for command output.
--query
(string)
A JMESPath query to use in filtering the response data.
--profile
(string)
Use a specific profile from your credential file.
--region
(string)
The region to use. Overrides config/env settings.
--version
(string)
Display the version of this tool.
--color
(string)
Turn on/off color output.
--no-sign-request
(boolean)
Do not sign requests. Credentials will not be loaded if this argument is provided.
--ca-bundle
(string)
The CA certificate bundle to use when verifying SSL certificates. Overrides config/env settings.
--cli-read-timeout
(int)
The maximum socket read time in seconds. If the value is set to 0, the socket read will be blocking and not timeout. The default value is 60 seconds.
--cli-connect-timeout
(int)
The maximum socket connect time in seconds. If the value is set to 0, the socket connect will be blocking and not timeout. The default value is 60 seconds.
--cli-binary-format
(string)
The formatting style to be used for binary blobs. The default format is base64. The base64 format expects binary blobs to be provided as a base64 encoded string. The raw-in-base64-out format preserves compatibility with AWS CLI V1 behavior and binary values must be passed literally. When providing contents from a file that map to a binary blob fileb://
will always be treated as binary and use the file contents directly regardless of the cli-binary-format
setting. When using file://
the file contents will need to properly formatted for the configured cli-binary-format
.
--no-cli-pager
(boolean)
Disable cli pager for output.
--cli-auto-prompt
(boolean)
Automatically prompt for CLI input parameters.
--no-cli-auto-prompt
(boolean)
Disable automatically prompt for CLI input parameters.
To use the following examples, you must have the AWS CLI installed and configured. See the Getting started guide in the AWS CLI User Guide for more information.
Unless otherwise stated, all examples have unix-like quotation rules. These examples will need to be adapted to your terminal’s quoting rules. See Using quotation marks with strings in the AWS CLI User Guide .
To generate a 256-bit symmetric data key without a plaintext key
The following generate-data-key-without-plaintext
example requests an encrypted copy of a 256-bit symmetric data key for use outside of AWS. You can call AWS KMS to decrypt the data key when you are ready to use it.
To request a 256-bit data key, use the key-spec
parameter with a value of AES_256
. To request a 128-bit data key, use the key-spec
parameter with a value of AES_128
. For all other data key lengths, use the number-of-bytes
parameter.
The KMS key you specify must be a symmetric encryption KMS key, that is, a KMS key with a key spec value of SYMMETRIC_DEFAULT.
aws kms generate-data-key-without-plaintext \
--key-id "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab" \
--key-spec AES_256
Output:
{
"CiphertextBlob": "AQEDAHjRYf5WytIc0C857tFSnBaPn2F8DgfmThbJlGfR8P3WlwAAAH4wfAYJKoZIhvcNAQcGoG8wbQIBADBoBgkqhkiG9w0BBwEwHgYJYIZIAWUDBAEuMBEEDEFogL",
"KeyId": "arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab"
}
The CiphertextBlob
(encrypted data key) is returned in base64-encoded format.
For more information, see Data keys in the AWS Key Management Service Developer Guide.