aws kms generate-data-key-without-plaintext

Generates a unique symmetric data key. This operation returns a data key that is encrypted under a customer master key (CMK) that you specify. To request an asymmetric data key pair, use the GenerateDataKeyPair or GenerateDataKeyPairWithoutPlaintext operations. GenerateDataKeyWithoutPlaintext is identical to the GenerateDataKey operation except that returns only the encrypted 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. GenerateDataKeyWithoutPlaintext returns a unique data key for each request. The bytes in the keys are not related to the caller or CMK that is used to encrypt the private key. To generate a data key, you must specify the symmetric customer master key (CMK) that is used to encrypt the data key. You cannot use an asymmetric CMK to generate a data key. To get the type of your CMK, use the DescribeKey operation. If the operation succeeds, you will find the encrypted copy of the data key in the CiphertextBlob field. You can use the 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 AWS Key Management Service Developer Guide. The CMK that you use for this operation must be in a compatible key state. For details, see How Key State Affects Use of a Customer Master Key in the AWS Key Management Service Developer Guide. 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:GenerateDataKeyWithoutPlaintext (key policy) Related operations: Decrypt Encrypt GenerateDataKey GenerateDataKeyPair GenerateDataKeyPairWithoutPlaintext

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