Function SecKeyGetCredentials 

pub unsafe extern "C-unwind" fn SecKeyGetCredentials(
    key_ref: &SecKey,
    operation: CSSM_ACL_AUTHORIZATION_TAG,
    credential_type: SecCredentialType,
    out_credentials: NonNull<*const CSSM_ACCESS_CREDENTIALS>,
) -> i32

👎Deprecated: renamed to SecKey::credentials

Available on crate features SecAsn1Types and SecBase and SecKey and cssmconfig and cssmtype only.