# sec_protocol_metadata_create_secret(_:_:_:_:) ``` func sec_protocol_metadata_create_secret(_ metadata: sec_protocol_metadata_t, _ label_len: Int, _ label: UnsafePointer, _ exporter_length: Int) -> dispatch_data_t? ``` ## Parameters `metadata` A `sec_protocol_metadata_t` instance. `label_len` Length of the KDF label string. `label` KDF label string. `exporter_length` Length of the secret to be exported. ## Return Value Returns a dispatch_data_t object carrying the exported secret. ## Discussion \abstract Export a secret, e.g., a cryptographic key, derived from the protocol metadata using a label string. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)