Ocamlnet 3 Reference Manual : Netauth

`sig
val hmac :
h:(string -> string) ->
b:int -> l:int -> k:string -> message:string -> string
type key_type = [ `Kc | `Ke | `Ki ]
val derive_key_rfc3961_simplified :
encrypt:(string -> string) ->
random_to_key:(string -> string) ->
block_size:int ->
k:int -> usage:int -> key_type:Netauth.key_type -> string
val xor_s : string -> string -> string
val add_1_complement : string -> string -> string
val rotate_right : int -> string -> string
val n_fold : int -> string -> string
end`