mirage-protocols 1.3.0 · OCaml Package

An IP stack that parses Ethernet frames into IP packets

type error = private [>

| Ip.error

]

The type for IP errors.

val pp_error : error Fmt.t

pp_error is the pretty-printer for errors.

type buffer

The type for memory buffers.

type ethif

The type for ethernet devices.

type ipaddr

The type for IP addresses.

type prefix

The type for IP prefixes.

include Mirage_device.S

type +'a io

The type for potentially blocking I/O operation

type t

The type representing the internal state of the device

val disconnect : t -> unit io

Disconnect from the device. While this might take some time to complete, it can never result in an error.

type callback = src:ipaddr -> dst:ipaddr -> buffer -> unit io

An input continuation used by the parsing functions to pass on an input packet down the stack.

callback ~src ~dst buf will be called with src and dst containing the source and destination IP address respectively, and buf will be a buffer pointing at the start of the IP payload.

val input : 
  t ->
  tcp:callback ->
  udp:callback ->
  default:(proto:int -> callback) ->
  buffer ->
  unit io

input ~tcp ~udp ~default ip buf demultiplexes an incoming buffer that contains an IP frame. It examines the protocol header and passes the result onto either the tcp or udp function, or the default function for unknown IP protocols.

val allocate_frame : 
  t ->
  dst:ipaddr ->
  proto:[ `ICMP | `TCP | `UDP ] ->
  buffer * int

allocate_frame t ~dst ~proto returns a pair (pkt, len) such that Cstruct.sub pkt 0 len is the IP header (including the link layer part) of a packet going to dst for protocol proto. The space in pkt after the first len bytes can be used by the client.

val write : t -> buffer -> buffer -> (unit, error) Pervasives.result io

write t frame buf writes the packet frame :: buf :: [] to the address dst.

val writev : t -> buffer -> buffer list -> (unit, error) Pervasives.result io

writev t frame bufs writes the packet frame :: bufs.

val checksum : buffer -> buffer list -> int

checksum frame bufs computes the IP checksum of bufs computing the pseudo-header from the actual header frame. It assumes that frame is of the form returned by allocate_frame, i.e., that it contains the link-layer part.

val pseudoheader : t -> dst:ipaddr -> proto:[< `TCP | `UDP ] -> int -> buffer

pseudoheader t dst proto len gives a pseudoheader suitable for use in TCP or UDP checksum calculation based on t.

val src : t -> dst:ipaddr -> ipaddr

src ip ~dst is the source address to be used to send a packet to dst. In the case of IPv4, this will always return the same IP, which is the only one set.

val set_ip : t -> ipaddr -> unit io

Set the IP address associated with this interface. For IPv4, currently only supports a single IPv4 address, and aliases will be added in a future revision.

val get_ip : t -> ipaddr list

Get the IP addresses associated with this interface. For IPv4, only * one IP address can be set at a time, so the list will always be of * length 1 (and may be the default value, 0.0.0.0).

type uipaddr

The type for universal IP addresses. It supports all the possible versions.

val to_uipaddr : ipaddr -> uipaddr

Convert an IP address with a specific version (eg. V4) into a universal IP address.

val of_uipaddr : uipaddr -> ipaddr option

Project a universal IP address into the version supported by the current implementation. Return None if there is a version mismatch.

val mtu : t -> int

mtu ip is the Maximum Transmission Unit of the ip i.e. the maximum size of the payload, not including the IP header.

package mirage-protocols