policy

The key policy to attach to the KMS key. This parameter is optional. If you do not provide a key policy, KMS attaches the default key policy to the KMS key.

The key policy is not a shared property of multi-Region keys. You can specify the same key policy or a different key policy for each key in a set of related multi-Region keys. KMS does not synchronize this property.

If you provide a key policy, it must meet the following criteria:

• The key policy must allow the calling principal to make a subsequent PutKeyPolicy request on the KMS key. This reduces the risk that the KMS key becomes unmanageable. For more information, see Default key policy in the Key Management Service Developer Guide. (To omit this condition, set BypassPolicyLockoutSafetyCheck to true.)

• Each statement in the key policy must contain one or more principals. The principals in the key policy must exist and be visible to KMS. When you create a new Amazon Web Services principal, you might need to enforce a delay before including the new principal in a key policy because the new principal might not be immediately visible to KMS. For more information, see Changes that I make are not always immediately visible in the Amazon Web Services Identity and Access Management User Guide.

A key policy document can include only the following characters:

• Printable ASCII characters from the space character (\u0020) through the end of the ASCII character range.

• Printable characters in the Basic Latin and Latin-1 Supplement character set (through \u00FF).

• The tab (\u0009), line feed (\u000A), and carriage return (\u000D) special characters

For information about key policies, see Key policies in KMS in the Key Management Service Developer Guide. For help writing and formatting a JSON policy document, see the IAM JSON Policy Reference in the Identity and Access Management User Guide.