ssekmsEncryptionContext

Specifies the Amazon Web Services KMS Encryption Context as an additional encryption context to use for the destination object encryption. The value of this header is a base64-encoded UTF-8 string holding JSON with the encryption context key-value pairs.

General purpose buckets - This value must be explicitly added to specify encryption context for CopyObject requests if you want an additional encryption context for your destination object. The additional encryption context of the source object won't be copied to the destination object. For more information, see Encryption context in the Amazon S3 User Guide.

Directory buckets - You can optionally provide an explicit encryption context value. The value must match the default encryption context - the bucket Amazon Resource Name (ARN). An additional encryption context value is not supported.