Skip to content

Client

kms R Documentation

AWS Key Management Service

Description

Key Management Service

Key Management Service (KMS) is an encryption and key management web service. This guide describes the KMS operations that you can call programmatically. For general information about KMS, see the Key Management Service Developer Guide .

KMS has replaced the term customer master key (CMK) with KMS key and KMS key. The concept has not changed. To prevent breaking changes, KMS is keeping some variations of this term.

Amazon Web Services provides SDKs that consist of libraries and sample code for various programming languages and platforms (Java, Ruby, .Net, macOS, Android, etc.). The SDKs provide a convenient way to create programmatic access to KMS and other Amazon Web Services services. For example, the SDKs take care of tasks such as signing requests (see below), managing errors, and retrying requests automatically. For more information about the Amazon Web Services SDKs, including how to download and install them, see Tools for Amazon Web Services.

We recommend that you use the Amazon Web Services SDKs to make programmatic API calls to KMS.

If you need to use FIPS 140-2 validated cryptographic modules when communicating with Amazon Web Services, use the FIPS endpoint in your preferred Amazon Web Services Region. For more information about the available FIPS endpoints, see Service endpoints in the Key Management Service topic of the Amazon Web Services General Reference.

All KMS API calls must be signed and be transmitted using Transport Layer Security (TLS). KMS recommends you always use the latest supported TLS version. Clients must also support cipher suites with Perfect Forward Secrecy (PFS) such as Ephemeral Diffie-Hellman (DHE) or Elliptic Curve Ephemeral Diffie-Hellman (ECDHE). Most modern systems such as Java 7 and later support these modes.

Signing Requests

Requests must be signed using an access key ID and a secret access key. We strongly recommend that you do not use your Amazon Web Services account root access key ID and secret access key for everyday work. You can use the access key ID and secret access key for an IAM user or you can use the Security Token Service (STS) to generate temporary security credentials and use those to sign requests.

All KMS requests must be signed with Signature Version 4.

Logging API Requests

KMS supports CloudTrail, a service that logs Amazon Web Services API calls and related events for your Amazon Web Services account and delivers them to an Amazon S3 bucket that you specify. By using the information collected by CloudTrail, you can determine what requests were made to KMS, who made the request, when it was made, and so on. To learn more about CloudTrail, including how to turn it on and find your log files, see the CloudTrail User Guide.

Additional Resources

For more information about credentials and request signing, see the following:

Commonly Used API Operations

Of the API operations discussed in this guide, the following will prove the most useful for most applications. You will likely perform operations other than these, such as creating keys and assigning policies, by using the console.

  • encrypt

  • decrypt

  • generate_data_key

  • generate_data_key_without_plaintext

Usage

kms(config = list(), credentials = list(), endpoint = NULL, region = NULL)

Arguments

config

Optional configuration of credentials, endpoint, and/or region.

  • credentials:

    • creds:

      • access_key_id: AWS access key ID

      • secret_access_key: AWS secret access key

      • session_token: AWS temporary session token

    • profile: The name of a profile to use. If not given, then the default profile is used.

    • anonymous: Set anonymous credentials.

  • endpoint: The complete URL to use for the constructed client.

  • region: The AWS Region used in instantiating the client.

  • close_connection: Immediately close all HTTP connections.

  • timeout: The time in seconds till a timeout exception is thrown when attempting to make a connection. The default is 60 seconds.

  • s3_force_path_style: Set this to true to force the request to use path-style addressing, i.e. ⁠http://s3.amazonaws.com/BUCKET/KEY⁠.

  • sts_regional_endpoint: Set sts regional endpoint resolver to regional or legacy https://docs.aws.amazon.com/sdkref/latest/guide/feature-sts-regionalized-endpoints.html

credentials

Optional credentials shorthand for the config parameter

  • creds:

    • access_key_id: AWS access key ID

    • secret_access_key: AWS secret access key

    • session_token: AWS temporary session token

  • profile: The name of a profile to use. If not given, then the default profile is used.

  • anonymous: Set anonymous credentials.

endpoint

Optional shorthand for complete URL to use for the constructed client.

region

Optional shorthand for AWS Region used in instantiating the client.

Value

A client for the service. You can call the service's operations using syntax like svc$operation(...), where svc is the name you've assigned to the client. The available operations are listed in the Operations section.

Service syntax

svc <- kms(
  config = list(
    credentials = list(
      creds = list(
        access_key_id = "string",
        secret_access_key = "string",
        session_token = "string"
      ),
      profile = "string",
      anonymous = "logical"
    ),
    endpoint = "string",
    region = "string",
    close_connection = "logical",
    timeout = "numeric",
    s3_force_path_style = "logical",
    sts_regional_endpoint = "string"
  ),
  credentials = list(
    creds = list(
      access_key_id = "string",
      secret_access_key = "string",
      session_token = "string"
    ),
    profile = "string",
    anonymous = "logical"
  ),
  endpoint = "string",
  region = "string"
)

Operations

cancel_key_deletion
Cancels the deletion of a KMS key
connect_custom_key_store
Connects or reconnects a custom key store to its backing key store
create_alias
Creates a friendly name for a KMS key
create_custom_key_store
Creates a custom key store backed by a key store that you own and manage
create_grant
Adds a grant to a KMS key
create_key
Creates a unique customer managed KMS key in your Amazon Web Services account and Region
decrypt
Decrypts ciphertext that was encrypted by a KMS key using any of the following operations:
delete_alias
Deletes the specified alias
delete_custom_key_store
Deletes a custom key store
delete_imported_key_material
Deletes key material that was previously imported
derive_shared_secret
Derives a shared secret using a key agreement algorithm
describe_custom_key_stores
Gets information about custom key stores in the account and Region
describe_key
Provides detailed information about a KMS key
disable_key
Sets the state of a KMS key to disabled
disable_key_rotation
Disables automatic rotation of the key material of the specified symmetric encryption KMS key
disconnect_custom_key_store
Disconnects the custom key store from its backing key store
enable_key
Sets the key state of a KMS key to enabled
enable_key_rotation
Enables automatic rotation of the key material of the specified symmetric encryption KMS key
encrypt
Encrypts plaintext of up to 4,096 bytes using a KMS key
generate_data_key
Returns a unique symmetric data key for use outside of KMS
generate_data_key_pair
Returns a unique asymmetric data key pair for use outside of KMS
generate_data_key_pair_without_plaintext
Returns a unique asymmetric data key pair for use outside of KMS
generate_data_key_without_plaintext
Returns a unique symmetric data key for use outside of KMS
generate_mac
Generates a hash-based message authentication code (HMAC) for a message using an HMAC KMS key and a MAC algorithm that the key supports
generate_random
Returns a random byte string that is cryptographically secure
get_key_policy
Gets a key policy attached to the specified KMS key
get_key_rotation_status
Provides detailed information about the rotation status for a KMS key, including whether automatic rotation of the key material is enabled for the specified KMS key, the rotation period, and the next scheduled rotation date
get_parameters_for_import
Returns the public key and an import token you need to import or reimport key material for a KMS key
get_public_key
Returns the public key of an asymmetric KMS key
import_key_material
Imports or reimports key material into an existing KMS key that was created without key material
list_aliases
Gets a list of aliases in the caller's Amazon Web Services account and region
list_grants
Gets a list of all grants for the specified KMS key
list_key_policies
Gets the names of the key policies that are attached to a KMS key
list_key_rotations
Returns information about all completed key material rotations for the specified KMS key
list_keys
Gets a list of all KMS keys in the caller's Amazon Web Services account and Region
list_resource_tags
Returns all tags on the specified KMS key
list_retirable_grants
Returns information about all grants in the Amazon Web Services account and Region that have the specified retiring principal
put_key_policy
Attaches a key policy to the specified KMS key
re_encrypt
Decrypts ciphertext and then reencrypts it entirely within KMS
replicate_key
Replicates a multi-Region key into the specified Region
retire_grant
Deletes a grant
revoke_grant
Deletes the specified grant
rotate_key_on_demand
Immediately initiates rotation of the key material of the specified symmetric encryption KMS key
schedule_key_deletion
Schedules the deletion of a KMS key
sign
Creates a digital signature for a message or message digest by using the private key in an asymmetric signing KMS key
tag_resource
Adds or edits tags on a customer managed key
untag_resource
Deletes tags from a customer managed key
update_alias
Associates an existing KMS alias with a different KMS key
update_custom_key_store
Changes the properties of a custom key store
update_key_description
Updates the description of a KMS key
update_primary_region
Changes the primary key of a multi-Region key
verify
Verifies a digital signature that was generated by the Sign operation
verify_mac
Verifies the hash-based message authentication code (HMAC) for a specified message, HMAC KMS key, and MAC algorithm

Examples

## Not run: 
svc <- kms()
# The following example cancels deletion of the specified KMS key.
svc$cancel_key_deletion(
  KeyId = "1234abcd-12ab-34cd-56ef-1234567890ab"
)

## End(Not run)