albatross/provision/albatross_provision.ml

100 lines
3.4 KiB
OCaml

(* (c) 2017 Hannes Mehnert, all rights reserved *)
let asn_version = `AV2
let timestamps validity =
let now = Ptime_clock.now () in
match Ptime.add_span now (Ptime.Span.of_int_s (Duration.to_sec validity)) with
| None -> Error (`Msg "span too big - reached end of ptime")
| Some exp -> Ok (now, exp)
let rec safe f arg =
try Ok (f arg) with
| Unix.Unix_error (Unix.EINTR, _, _) -> safe f arg
| Unix.Unix_error (e, _, _) -> Error (`Msg (Unix.error_message e))
(* TODO: is this useful elsewhere? *)
let append name data =
let open Rresult.R.Infix in
let buf = Bytes.unsafe_of_string data in
let nam = Fpath.to_string name in
safe Unix.(openfile nam [ O_APPEND ; O_CREAT ; O_WRONLY ]) 0o644 >>= fun fd ->
let len = String.length data in
let rec go off =
let l = len - off in
safe (Unix.write fd buf off) l >>= fun w ->
if l = w then Ok ()
else go (w + off)
in
go 0 >>= fun () ->
safe Unix.close fd
let key_ids pub issuer =
let auth = (Some (X509.key_id issuer), [], None) in
[ (false, `Subject_key_id (X509.key_id pub)) ; (false, `Authority_key_id auth) ]
let sign ?dbname ?certname extensions issuer key csr delta =
let open Rresult.R.Infix in
(match certname with
| Some x -> Ok x
| None ->
(try Ok (List.find (function `CN _ -> true | _ -> false) (X509.CA.info csr).X509.CA.subject)
with Not_found -> Error (`Msg "unable to discover certificate name")) >>= function
| `CN name -> Ok name
| _ -> Error (`Msg "cannot happen")) >>= fun certname ->
timestamps delta >>= fun (valid_from, valid_until) ->
let extensions =
match dbname with
| None -> extensions (* evil hack to avoid issuer + public key for CA cert *)
| Some _ ->
match key with
| `RSA priv ->
let capub = `RSA (Nocrypto.Rsa.pub_of_priv priv) in
extensions @ key_ids (X509.CA.info csr).X509.CA.public_key capub
in
let cert = X509.CA.sign csr ~valid_from ~valid_until ~extensions key issuer in
(match dbname with
| None -> Ok () (* no DB! *)
| Some dbname ->
append dbname (Printf.sprintf "%s %s\n" (Z.to_string (X509.serial cert)) certname)) >>= fun () ->
let enc = X509.Encoding.Pem.Certificate.to_pem_cstruct1 cert in
Bos.OS.File.write Fpath.(v certname + "pem") (Cstruct.to_string enc)
let priv_key ?(bits = 2048) fn name =
let open Rresult.R.Infix in
let file = match fn with
| None -> Fpath.(v name + "key")
| Some f -> Fpath.v f
in
Bos.OS.File.exists file >>= function
| false ->
Logs.info (fun m -> m "creating new RSA key %a" Fpath.pp file) ;
let priv = `RSA (Nocrypto.Rsa.generate bits) in
Bos.OS.File.write ~mode:0o400 file (Cstruct.to_string (X509.Encoding.Pem.Private_key.to_pem_cstruct1 priv)) >>= fun () ->
Ok priv
| true ->
Bos.OS.File.read file >>= fun s ->
Ok (X509.Encoding.Pem.Private_key.of_pem_cstruct1 (Cstruct.of_string s))
open Cmdliner
let nam =
let doc = "Name to provision" in
Arg.(required & pos 0 (some string) None & info [] ~doc ~docv:"VM")
let cacert =
let doc = "cacert" in
Arg.(required & pos 1 (some file) None & info [] ~doc ~docv:"CACERT")
let key =
let doc = "Private key" in
Arg.(value & opt (some file) None & info [ "key" ] ~doc)
let db =
let doc = "Database" in
Arg.(required & pos 0 (some string) None & info [] ~doc ~docv:"DB")
let mem =
let doc = "Memory to provision" in
Arg.(required & pos 2 (some int) None & info [] ~doc ~docv:"MEM")