Use ListKeyPolicies with an AWS SDK or CLI

To get the names of key policies for a KMS key

The following list-key-policies example gets the names of the key policies for a customer managed key in the example account and Region. You can use this command to find the names of key policies for AWS managed keys and customer managed keys.

Because the only valid key policy name is default, this command is not useful.

To specify the KMS key, use the key-id parameter. This example uses a key ID value, but you can use a key ID or key ARN in this command.

aws kms list-key-policies \
    --key-id 1234abcd-12ab-34cd-56ef-1234567890ab

Output:

{
    "PolicyNames": [
    "default"
    ]
}

For more information about AWS KMS key policies, see Using Key Policies in AWS KMS in the AWS Key Management Service Developer Guide.

    /**
     * Asynchronously retrieves the key policy for the specified key ID and policy name.
     *
     * @param keyId       the ID of the AWS KMS key for which to retrieve the policy
     * @param policyName the name of the key policy to retrieve
     * @return a {@link CompletableFuture} that, when completed, contains the key policy as a {@link String}
     */
    public CompletableFuture<String> getKeyPolicyAsync(String keyId, String policyName) {
        GetKeyPolicyRequest policyRequest = GetKeyPolicyRequest.builder()
            .keyId(keyId)
            .policyName(policyName)
            .build();

        return getAsyncClient().getKeyPolicy(policyRequest)
            .thenApply(response -> {
                String policy = response.policy();
                logger.info("The response is: " + policy);
                return policy;
            })
            .exceptionally(ex -> {
                throw new RuntimeException("Failed to get key policy", ex);
            });
    }

class KeyPolicy:
    def __init__(self, kms_client):
        self.kms_client = kms_client

    @classmethod
    def from_client(cls) -> "KeyPolicy":
        """
        Creates a KeyPolicy instance with a default KMS client.

        :return: An instance of KeyPolicy initialized with the default KMS client.
        """
        kms_client = boto3.client("kms")
        return cls(kms_client)


    def list_policies(self, key_id):
        """
        Lists the names of the policies for a key.

        :param key_id: The ARN or ID of the key to query.
        """
        try:
            policy_names = self.kms_client.list_key_policies(KeyId=key_id)[
                "PolicyNames"
            ]
        except ClientError as err:
            logging.error(
                "Couldn't list your policies. Here's why: %s",
                err.response["Error"]["Message"],
            )
            raise
        else:
            print(f"The policies for key {key_id} are:")
            pprint(policy_names)