P256.SHA2_256Buffers have the following size constraints:
pk: 64 bytes, corresponding to the "raw" representation of an elliptic curve point (see Point representation and conversions)sk, k: 32 bytessignature: 64 bytesmsg: no size requirement for variants using SHA-2 hashing (see ECDSA)type bytes = SharedDefs.CBytes.tsign sk msg k attempts to sign the message msg with secret key sk and signing secret k and returns the signature if successful.
verify pk msg signature checks the signature of msg using public key pk and returns true if it is valid.
module Noalloc : sig ... endVersions of these functions which write their output in a buffer passed in as an argument