Because of Wasm constraints at the time of writing, some cryptographic libraries cannot be compiled to Wasm. In the meantime, Kubewarden policies needing those can instead perform these callbacks to evaluate the cryptographic functions host-side, receive the result, and continue with their logic.
WaPC protocol contract
In case you are implementing your own language SDK, these are the functions performing cryptographic checks exposed by the host:
|waPC function name||Input payload||Output payload|