GrantConstraints - Amazon Key Management Service
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GrantConstraints

Use this structure to allow cryptographic operations in the grant only when the operation request includes the specified encryption context.

Amazon KMS applies the grant constraints only to cryptographic operations that support an encryption context, that is, all cryptographic operations with a symmetric KMS key. Grant constraints are not applied to operations that do not support an encryption context, such as cryptographic operations with asymmetric KMS keys and management operations, such as DescribeKey or RetireGrant.

Important

In a cryptographic operation, the encryption context in the decryption operation must be an exact, case-sensitive match for the keys and values in the encryption context of the encryption operation. Only the order of the pairs can vary.

However, in a grant constraint, the key in each key-value pair is not case sensitive, but the value is case sensitive.

To avoid confusion, do not use multiple encryption context pairs that differ only by case. To require a fully case-sensitive encryption context, use the kms:EncryptionContext: and kms:EncryptionContextKeys conditions in an IAM or key policy. For details, see kms:EncryptionContext:context-key in the Amazon Key Management Service Developer Guide .

Contents

Note

In the following list, the required parameters are described first.

EncryptionContextEquals

A list of key-value pairs that must match the encryption context in the cryptographic operation request. The grant allows the operation only when the encryption context in the request is the same as the encryption context specified in this constraint.

Type: String to string map

Required: No

EncryptionContextSubset

A list of key-value pairs that must be included in the encryption context of the cryptographic operation request. The grant allows the cryptographic operation only when the encryption context in the request includes the key-value pairs specified in this constraint, although it can include additional key-value pairs.

Type: String to string map

Required: No

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: