The MirageOS Blog

Let’s Encrypt

opam update
opam upgrade solo5

open Mrmime

let romain_calascibetta =
  let open Mailbox in
  Local.[ w "romain"; w "calascibetta" ] @ Domain.(domain, [ a "gmail"; a "com" ])

let tarides =
  let open Mailbox in
  Local.[ w "contact" ] @ Domain.(domain, [ a "tarides"; a "com" ])

let date = Date.of_ptime ~zone:Date.Zone.GMT (Ptime_clock.now ())

let content_type =
  Content_type.(make `Text (Subtype.v `Text "plain") Parameters.empty)

let subject =
  let open Unstructured.Craft in
  compile [ v "A"; sp 1; v "simple"; sp 1; v "email" ]

let header =
  let open Header in
  empty
  |> add Field_name.date Field.(Date, date)
  |> add Field_name.subject Field.(Unstructured, subject)
  |> add Field_name.from Field.(Mailboxes, [ romain_calascibetta ])
  |> add (Field_name.v "To") Field.(Addresses, Address.[ mailbox tarides ])
  |> add Field_name.content_encoding Field.(Encoding, `Quoted_printable)

let stream_of_stdin () = match input_line stdin with
  | line -> Some (line, 0, String.length line)
  | exception _ -> None

let v =
  let part = Mt.part ~header stream_of_stdin in
  Mt.make Header.empty Mt.simple part

let () =
  let stream = Mt.to_stream v in
  let rec go () = match stream () with
    | Some (str, off, len) ->
      output_substring stdout str off len ;
      go ()
    | None -> () in
  go ()

(* $ ocamlfind opt -linkpkg -package mrmime,ptime.clock.os in.ml -o in.exe
   $ echo "Hello World\\!" | ./in.exe > mail.eml
*)

open Mrmime

let ps =
  let open Field_name in
  Map.empty
  |> Map.add from Field.(Witness Mailboxes)
  |> Map.add (v "To") Field.(Witness Addresses)
  |> Map.add cc Field.(Witness Addresses)
  |> Map.add bcc Field.(Witness Addresses)
  |> Map.add sender Field.(Witness Mailbox)

let parse ic =
  let decoder = Hd.decoder ps in
  let rec go (addresses : Emile.mailbox list) =
    match Hd.decode decoder with
    | `Malformed err -> failwith err
    | `Field field ->
      ( match Location.prj field with
      | Field (_, Mailboxes, vs) ->
        go (vs @ addresses)
      | Field (_, Mailbox, v) ->
        go (v :: addresses)
      | Field (_, Addresses, vs) ->
        let vs =
          let f = function
            | `Group { Emile.mailboxes; _ } ->
              mailboxes
            | `Mailbox m -> [ m ] in
          List.(concat (map f vs)) in
        go (vs @ addresses)
      | _ -> go addresses )
    | `End _ -> addresses
    | `Await -> match input_line ic with
      | "" -> go addresses
      | line
        when String.length line >= 1
          && line.[String.length line - 1] = '\\r' ->
        Hd.src decoder (line ^ "\\n") 0
          (String.length line + 1) ;
        go addresses
      | line ->
        Hd.src decoder (line ^ "\\r\\n") 0
          (String.length line + 2) ;
        go addresses
      | exception _ ->
        Hd.src decoder "" 0 0 ;
        go addresses in
  go []

let () =
  let vs = parse stdin in
  List.iter (Format.printf "%a\\n%!" Emile.pp_mailbox) vs

(* $ ocamlfind opt -linkpkg -package mrmime out.ml -o out.exe
   $ echo "Hello World\\!" | ./in.exe | ./out.exe
   romain.calascibetta@gmail.com
   contact@tarides.com
*)

$ blaze.make --from din@osau.re \\
  | blaze.make wrap --mixed \\
  | blaze.make put --type image/png --encoding base64 image.png \\
  | blaze.submit --sender din@osau.re --password ****** osau.re

$ opam install "mirage>4" "dune>=3.2.0"
$ git clone https://github.com/mirage/dns-resolver
$ cd dns-resolver
dns-resolver $ mirage configure -t hvt

 dns-resolver/
 ┣ config.ml
 ┣ unikernel.ml
 ┃
 ┣ Makefile
 ┣ dune             <- switch between config and build
 ┣ dune.config      <- configuration build rules
 ┣ dune.build       <- unikernel build rules
 ┣ dune-project     <- dune project definition
 ┣ dune-workspace   <- build contexts definition
 ┣ mirage/
 ┃  ┣ context
 ┃  ┣ key_gen.ml
 ┃  ┣ main.ml
 ┃  ┣ <...>-<target>-monorepo.opam
 ┃  ┗ <...>-<target>-switch.opam
 ┗ dist/
   ┗ dune           <- rules to produce artifacts

$ make depends

(include dune.config)

(data_only_dirs duniverse)

(executable
 (name config)
 (flags (:standard -warn-error -A))
 (modules config)
 (libraries mirage))

(lang dune 2.0)

(profile release)

(context (default))

(context (default
  (name solo5)      ; name of the context
  (host default)    ; inform dune that this is cross-compilation
  (toolchain solo5) ; use the ocaml-solo5 compiler toolchain
  (merlin)          ; enable merlin for this context
  (disable_dynamically_linked_foreign_archives true)
))

(copy_files ./mirage/*)

(executable
 (enabled_if (= %{context_name} "solo5"))
 (name main)
 (modes (native exe))
 (libraries arp.mirage dns dns-mirage dns-resolver.mirage dns-server
   ethernet logs lwt mirage-bootvar-solo5 mirage-clock-solo5
   mirage-crypto-rng-mirage mirage-logs mirage-net-solo5 mirage-random
   mirage-runtime mirage-solo5 mirage-time tcpip.icmpv4 tcpip.ipv4
   tcpip.ipv6 tcpip.stack-direct tcpip.tcp tcpip.udp)
 (link_flags :standard -w -70 -color always -cclib "-z solo5-abi=hvt")
 (modules (:standard \\ config manifest))
 (foreign_stubs (language c) (names manifest))
)

(rule
 (targets manifest.c)
 (deps manifest.json)
 (action
  (run solo5-elftool gen-manifest manifest.json manifest.c)))

(rule
 (target resolver.hvt)
 (enabled_if (= %{context_name} "solo5"))
 (deps main.exe)
 (action
  (copy main.exe %{target})))

(alias
  (name default)
  (enabled_if (= %{context_name} "solo5"))
  (deps (alias_rec all)))

(rule
 (mode (promote (until-clean)))
 (target resolver.hvt)
 (enabled_if (= %{context_name} "solo5"))
 (action
  (copy ../resolver.hvt %{target})))

$ make build

$ mirage build

$ dune build --root .

$ opam pin solo5-cross-aarch64 https://github.com/Solo5/solo5.git#v0.7.1
$ opam pin ocaml-solo5-cross-aarch64 https://github.com/mirage/ocaml-solo5.git#v0.8.0

$ dune build / mirage build / make

$ file dist/resolver.hvt
dist/resolver.hvt: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), statically linked, interpreter /nonexistent/solo5/, for OpenBSD, with debug_info, not stripped

$ opam update
$ opam install 'mirage>4'

The MirageOS Blog

MirageOS Security Advisory 03 - infinite loop in console output on xen

Background

Problem Description

Impact

Workaround

Solution

Correction details

Timeline

References

Network setup

Day to day activities

OCaml 5 support

A Verified File System for MirageOS

Uint128

Qubes firewall

Music bare-metal on Raspberry Pi 4

HTTP client for MirageOS

DNS resolver with filtering advertisement

Albatross meets NixOS

Memory leaks

Opam cache

Fixing the DNS resolver in the mirage tool

Caqti and pgx

Lwt

Tarides Map

Slack bot

OpenVPN

CalDAV

DNS Projects

Observations and an Issue Rises

Several Avenues to Explore

Sharing Files as a Side Project

MirageOS 4

A Tour of the Many Email Libraries

Parsing and Serialising Emails with Mr. MIME

Sending Emails with SMTP

Manipulate Emails with CLI tools

Deploying Email Services as Unikernels

The MirageOS 4 Build System

Preliminary Steps

What is a Configured Unikernel ?

dune Files

./dune

./dune.config

./dune-workspace

./dune.build

./dist/dune

Cross-Compiling to x86_64/hvt

Cross-Compiling to ARM64/HVT

Compiling to a New Target or Architecture

Case 1: An Already Known Mirage Target (Unix / HVT / etc.)

Case 2: A New Target

Conclusion

Install MirageOS 4

About MirageOS

What’s New in MirageOS 4?

About Cross-Compilation and opam overlays

In Memory of Lars Kurth

`dune` Files

`./dune`

`./dune.config`

`./dune-workspace`

`./dune.build`

`./dist/dune`

Cross-Compiling to `x86_64/hvt`