Adds a grant to a KMS key.
A
grant is a policy instrument that allows Amazon Web Services principals to use KMS keys in cryptographic operations. It also can allow them to view a KMS key (
DescribeKey) and create and manage grants. When authorizing access to a KMS key, grants are considered along with key policies and IAM policies. Grants are often used for temporary permissions because you can create one, use its permissions, and delete it without changing your key policies or IAM policies.
For detailed information about grants, including grant terminology, see
Grants in KMS in the
Key Management Service Developer Guide. For examples of working with grants in several programming languages, see
Programming grants.
The
CreateGrant operation returns a
GrantToken and a
GrantId.
- When you create, retire, or revoke a grant, there might be a brief delay, usually less than five minutes, until the grant is available throughout KMS. This state is known as eventual consistency. Once the grant has achieved eventual consistency, the grantee principal can use the permissions in the grant without identifying the grant.
However, to use the permissions in the grant immediately, use the GrantToken that CreateGrant returns. For details, see Using a grant token in the Key Management Service Developer Guide.
- The CreateGrant operation also returns a GrantId. You can use the GrantId and a key identifier to identify the grant in the RetireGrant and RevokeGrant operations. To find the grant ID, use the ListGrants or ListRetirableGrants operations.
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 on a KMS key in a different Amazon Web Services account, specify the key ARN in the value of the
KeyId parameter.
Required permissions:
kms:CreateGrant (key policy)
Related operations:Eventual consistency: The KMS API follows an eventual consistency model. For more information, see
KMS eventual consistency.