commit a3a8235c8aa7b15a8b13342a160c47f5a669dc99 · patrick.sirref.org/shelter

+3

.gitignore

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       *.sjson

     

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       *.json

     

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       *.shl

     

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       docs/trees

     

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       docs/output

src/bin/dune src/shelter/bin/dune

src/bin/main.ml src/shelter/bin/main.ml

+44

src/common/admin.ml

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       open Capnp_rpc

     

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       let v sr ~add_user ~remove_user =

     

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         let module X = Raw.Service.Admin in

     

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         Capnp_rpc.Persistence.with_sturdy_ref sr X.local

     

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         @@ object

     

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              inherit X.service

     

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              method add_user_impl params release_param_caps =

     

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                let open X.AddUser in

     

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                let id = Params.user_get params in

     

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                release_param_caps ();

     

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                let cap = add_user id in

     

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                let response, results = Service.Response.create Results.init_pointer in

     

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                Results.cap_set results (Some cap);

     

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                Capability.dec_ref cap;

     

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                Service.return response

     

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              method remove_user_impl params release_param_caps =

     

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                let open X.RemoveUser in

     

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                let id = Params.user_get params in

     

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                release_param_caps ();

     

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                remove_user id;

     

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                Service.return @@ Service.Response.create_empty ()

     

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            end

     

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       module X = Raw.Client.Admin

     

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       type t = X.t Capability.t

     

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       let add_user t user =

     

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         let open X.AddUser in

     

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         let request, params = Capability.Request.create Params.init_pointer in

     

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         Params.user_set params user;

     

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         Capability.call_for_caps t method_id request Results.cap_get_pipelined

     

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       let remove_user t user =

     

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         let open X.RemoveUser in

     

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         let request, params = Capability.Request.create Params.init_pointer in

     

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         Params.user_set params user;

     

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         let _ : _ StructStorage.reader_t =

     

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           Capability.call_for_value_exn t method_id request

     

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         in

     

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         ()

+1

src/common/config.ml

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       type t = { shell : string; default_image : string } [@@deriving yojson]

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src/common/dune

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       (rule

     

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        (targets schema.ml schema.mli)

     

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        (deps schema.capnp)

     

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        (action

     

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         (run capnpc -o %{bin:capnpc-ocaml} %{deps})))

     

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       (library

     

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        (name shelter_common)

     

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        (preprocess

     

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         (pps ppx_deriving_yojson))

     

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        (flags

     

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         (:standard -w -53-55))

     

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        (libraries capnp-rpc-net))

+1

src/common/raw.ml

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       include Schema.MakeRPC (Capnp_rpc)

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src/common/schema.capnp

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       @0x91b3108e7ebb3830;

     

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       interface Session {

     

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         stdin  @0 (input :Text) -> ();

     

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         stdout @1 () -> (output :Text);

     

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         stderr @2 () -> (output :Text);

     

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       }

     

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       interface User {

     

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         connect @0 (config :Text) -> (cap :Session);

     

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         # Connect to the daemon and get a live session.

     

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       }

     

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       interface Admin {

     

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         addUser @0 (user :Text) -> (cap :User);

     

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         # Add a new user, returning a capability to act as a full

     

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         # Shelter user.

     

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         removeUser @1 (user :Text) -> ();

     

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         # Remove a user, this will also cancel existing connections

     

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         # this user may have to the daemon.

     

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       }

+57

src/common/session.ml

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       open Capnp_rpc

     

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       let or_fail = function

     

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         | Ok v -> v

     

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         | Error (`Capnp e) -> Fmt.failwith "%a" Capnp_rpc.Error.pp e

     

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       let local ~stdin ~stdout ~stderr =

     

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         let module X = Raw.Service.Session in

     

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         X.local

     

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         @@ object

     

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              inherit X.service

     

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              method stdout_impl _ release_param_caps =

     

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                let open X.Stdout in

     

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                release_param_caps ();

     

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                let s = stdout () in

     

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                let response, results = Service.Response.create Results.init_pointer in

     

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                Results.output_set results s;

     

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                Service.return response

     

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              method stderr_impl _ release_param_caps =

     

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                let open X.Stderr in

     

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                release_param_caps ();

     

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                let s = stderr () in

     

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                let response, results = Service.Response.create Results.init_pointer in

     

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                Results.output_set results s;

     

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                Service.return response

     

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              method stdin_impl params release_param_caps =

     

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                let open X.Stdin in

     

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                let data = Params.input_get params in

     

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                release_param_caps ();

     

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                stdin data;

     

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                Service.return_empty ()

     

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            end

     

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       module X = Raw.Client.Session

     

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       type t = X.t Capability.t

     

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       let stdout t () =

     

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         let open X.Stdout in

     

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         let request = Capability.Request.create_no_args () in

     

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         let result = Capability.call_for_value t method_id request |> or_fail in

     

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         Results.output_get result

     

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       let stderr t () =

     

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         let open X.Stderr in

     

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         let request = Capability.Request.create_no_args () in

     

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         let result = Capability.call_for_value t method_id request |> or_fail in

     

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         Results.output_get result

     

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       let stdin t input =

     

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         let open X.Stdin in

     

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         let request, params = Capability.Request.create Params.init_pointer in

     

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         Params.input_set params input;

     

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         Capability.call_for_unit t method_id request |> or_fail

+6

src/common/shelter_common.ml

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       let or_fail = function Ok v -> v | Error (`Msg m) -> failwith m

     

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       module Raw = Raw

     

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       module Admin = Admin

     

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       module User = User

     

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       module Session = Session

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src/common/user.ml

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       open Capnp_rpc

     

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       let v sr connect =

     

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         let module X = Raw.Service.User in

     

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         Capnp_rpc.Persistence.with_sturdy_ref sr X.local

     

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         @@ object

     

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              inherit X.service

     

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              method connect_impl params release_param_caps =

     

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                let open X.Connect in

     

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                let config =

     

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                  Params.config_get params |> Yojson.Safe.from_string

     

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                  |> Config.of_yojson |> Result.get_ok

     

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                in

     

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                release_param_caps ();

     

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                let cap = connect config in

     

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                let response, results = Service.Response.create Results.init_pointer in

     

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                Results.cap_set results (Some cap);

     

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                Capability.dec_ref cap;

     

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                Service.return response

     

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            end

     

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       module X = Raw.Client.User

     

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       type t = X.t Capability.t

     

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       let connect t config =

     

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         let open X.Connect in

     

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         let request, params = Capability.Request.create Params.init_pointer in

     

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         Params.config_set params (Config.to_yojson config |> Yojson.Safe.to_string);

     

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         Capability.call_for_caps t method_id request Results.cap_get_pipelined

src/lib/dune src/shelter/lib/dune

src/lib/engine.ml src/shelter/lib/engine.ml

src/lib/history.ml src/shelter/lib/history.ml

src/lib/passthrough/dune src/shelter/lib/passthrough/dune

src/lib/passthrough/shelter_passthrough.ml src/shelter/lib/passthrough/shelter_passthrough.ml

src/lib/passthrough/shelter_passthrough.mli src/shelter/lib/passthrough/shelter_passthrough.mli

src/lib/script.ml src/shelter/lib/script.ml

src/lib/shelter.ml src/shelter/lib/shelter.ml

src/lib/shelter/config.ml src/shelter/lib/shelter/config.ml

src/lib/shelter/diff.ml src/shelter/lib/shelter/diff.ml

src/lib/shelter/dune src/shelter/lib/shelter/dune

src/lib/shelter/fetch.ml src/shelter/lib/shelter/fetch.ml

src/lib/shelter/opentrace src/shelter/lib/shelter/opentrace

src/lib/shelter/runc.ml src/shelter/lib/shelter/runc.ml

src/lib/shelter/shelter_main.ml src/shelter/lib/shelter/shelter_main.ml

src/lib/shelter/shelter_main.mli src/shelter/lib/shelter/shelter_main.mli

src/lib/shelter/store.ml src/shelter/lib/shelter/store.ml

src/lib/shelter/tools.ml src/shelter/lib/shelter/tools.ml

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src/shelterd/dune

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       (executable

     

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        (name main)

     

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        (public_name shelterd)

     

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        (libraries eio_main shelter_common capnp-rpc-unix index.unix))

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src/shelterd/main.ml

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       open Shelter_common

     

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       open Capnp_rpc

     

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       module Admin = struct

     

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         module Secret = Capnp_rpc_net.Restorer.Id

     

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         let add_user t restorer name =

     

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           match Store.lookup t name with

     

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           | Some _ -> Fmt.failwith "User %s already exists!" name

     

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           | None -> (

     

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               let secret = Store.add_client t name in

     

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               match Capnp_rpc_net.Restorer.restore restorer secret with

     

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               | Ok v -> v

     

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               | Error exn ->

     

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                   Fmt.failwith "%a" Capnp_rpc_proto.Error.pp (`Exception exn))

     

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         let remove_user t name = Store.remove t name

     

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         let v sr restorer t =

     

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           let add_user = add_user t restorer in

     

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           let remove_user = remove_user t in

     

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           Admin.v ~add_user ~remove_user sr

     

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       end

     

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       open Capnp_rpc_net

     

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       let export ~secrets_dir ~vat ~name id =

     

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         let ( / ) = Filename.concat in

     

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         let path = secrets_dir / (name ^ ".cap") in

     

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         Capnp_rpc_unix.Cap_file.save_service vat id path |> or_fail;

     

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         Logs.app (fun f -> f "Wrote capability reference to %S" path)

     

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       let daemon capnp services store secrets_dir =

     

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         let restore = Restorer.of_table services in

     

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         let admin_id = Capnp_rpc_unix.Vat_config.derived_id capnp "admin" in

     

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         let admin =

     

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           let sr = Capnp_rpc_net.Restorer.Table.sturdy_ref services admin_id in

     

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           Admin.v sr restore store

     

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         in

     

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         Restorer.Table.add services admin_id admin;

     

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         Eio.Switch.run @@ fun sw ->

     

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         let vat = Capnp_rpc_unix.serve capnp ~sw ~restore in

     

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         export ~secrets_dir ~vat ~name:"admin" admin_id;

     

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         Logs.app (fun f -> f "shelterd running...");

     

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         Eio.Promise.await (Eio.Promise.create () |> fst)

     

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       open Cmdliner

     

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       +
       

     

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       let setup_log style_renderer level =

     

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         Fmt_tty.setup_std_outputs ?style_renderer ();

     

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         Logs.set_level level;

     

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         Logs.set_reporter (Logs_fmt.reporter ());

     

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         ()

     

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       +
       

     

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       let setup_log =

     

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         let docs = Manpage.s_common_options in

     

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         Term.(

     

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           const setup_log $ Fmt_cli.style_renderer ~docs () $ Logs_cli.level ~docs ())

     

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       +
       

     

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       let admin =

     

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         Arg.required

     

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         @@ Arg.opt Arg.(some file) None

     

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         @@ Arg.info ~doc:"Path of the admin capability." ~docv:"ADDR"

     

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              [ "c"; "connect" ]

     

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       +
       

     

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       let username =

     

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         Arg.required

     

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         @@ Arg.pos 0 Arg.(some string) None

     

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         @@ Arg.info ~doc:"The name of the new user to add." ~docv:"NAME" []

     

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       +
       

     

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       let daemon env =

     

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         let doc = "run the shelter daemon" in

     

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         let man =

     

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           [

     

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             `S Manpage.s_description;

     

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             `P "The shelter daemon provides a way to run sessions for shelter users.";

     

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           ]

     

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         in

     

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         let info = Cmd.info ~man "daemon" ~doc in

     

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         let daemon () capnp =

     

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           let make_sturdy = Capnp_rpc_unix.Vat_config.sturdy_uri capnp in

     

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           let connect = Obj.magic () in

     

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           let load ~validate:_ ~sturdy_ref =

     

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             let sr = Capnp_rpc.Sturdy_ref.cast sturdy_ref in

     

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             Restorer.grant (User.v sr connect)

     

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           in

     

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           let loader = Store.create ~make_sturdy ~load "shelter.index" in

     

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           Eio.Switch.run @@ fun sw ->

     

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           let services = Restorer.Table.of_loader ~sw (module Store) loader in

     

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           daemon capnp services loader.store "./secrets"

     

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         in

     

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         let term =

     

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           Term.(const daemon $ setup_log $ Capnp_rpc_unix.Vat_config.cmd env)

     

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         in

     

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         (Cmd.v info term, term)

     

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       +
       

     

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       let add_cmd env =

     

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       +
         let doc = "add a new client" in

     

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       +
         let man =

     

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           [

     

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             `S Manpage.s_description;

     

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       +
             `P

     

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               "Add a new client and get a capablity back to use for that client to \

     

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                run shelter sessions.";

     

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           ]

     

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         in

     

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         let info = Cmd.info ~man "add" ~doc in

     

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         let add () cap_path name =

     

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           Eio.Switch.run @@ fun sw ->

     

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           let vat = Capnp_rpc_unix.client_only_vat ~sw env#net in

     

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           let sr = Capnp_rpc_unix.Cap_file.load vat cap_path |> or_fail in

     

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           Capnp_rpc_unix.with_cap_exn sr @@ fun service ->

     

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       +
           let cap = Shelter_common.Admin.add_user service name in

     

       114
       114
       +
           Capability.with_ref cap @@ fun client ->

     

       115
       115
       +
           let uri = Persistence.save_exn client in

     

       116
       116
       +
           Fmt.pr "%a" Uri.pp uri

     

       117
       117
       +
         in

     

       118
       118
       +
         Cmd.v info Term.(const add $ setup_log $ admin $ username)

     

       119
       119
       +
       

     

       120
       120
       +
       let () =

     

       121
       121
       +
         Eio_main.run @@ fun env ->

     

       122
       122
       +
         let doc = "Shelterd" in

     

       123
       123
       +
         let man =

     

       124
       124
       +
           [

     

       125
       125
       +
             `S Manpage.s_authors;

     

       126
       126
       +
             `P "Patrick Ferris";

     

       127
       127
       +
             `S Manpage.s_bugs;

     

       128
       128
       +
             `P "Email bug reports to <patrick@sirref.org>.";

     

       129
       129
       +
           ]

     

       130
       130
       +
         in

     

       131
       131
       +
         let info = Cmd.info ~doc ~man "shelterd" in

     

       132
       132
       +
         let daemon_cmd, daemon_term = daemon env in

     

       133
       133
       +
         exit

     

       134
       134
       +
           (Cmd.eval @@ Cmd.group ~default:daemon_term info [ daemon_cmd; add_cmd env ])

+71

src/shelterd/store.ml

···

       1
       1
       +
       (* let () = Mirage_crypto_rng_lwt.initialize (module Mirage_crypto_rng.Fortuna) *)

     

       2
       2
       +
       let hash_size = 256

     

       3
       3
       +
       

     

       4
       4
       +
       module Fixed_string = Index.Key.String_fixed (struct

     

       5
       5
       +
         let length = 256

     

       6
       6
       +
       end)

     

       7
       7
       +
       

     

       8
       8
       +
       module I = Index_unix.Make (Fixed_string) (Fixed_string) (Index.Cache.Noop)

     

       9
       9
       +
       module Secret = Capnp_rpc_net.Restorer.Id

     

       10
       10
       +
       

     

       11
       11
       +
       type t = {

     

       12
       12
       +
         store : I.t;

     

       13
       13
       +
         make_sturdy : Secret.t -> Uri.t;

     

       14
       14
       +
         load :

     

       15
       15
       +
           validate:(unit -> bool) ->

     

       16
       16
       +
           sturdy_ref:[ `Generic ] Capnp_rpc.Sturdy_ref.t ->

     

       17
       17
       +
           Capnp_rpc_net.Restorer.resolution;

     

       18
       18
       +
       }

     

       19
       19
       +
       

     

       20
       20
       +
       let create ~make_sturdy ~load path =

     

       21
       21
       +
         let store = I.v ~log_size:4096 path in

     

       22
       22
       +
         { store; make_sturdy; load }

     

       23
       23
       +
       

     

       24
       24
       +
       let pad_name name =

     

       25
       25
       +
         let diff = hash_size - String.length name in

     

       26
       26
       +
         if diff >= 0 then String.make diff ' ' ^ name else failwith "Name too long!"

     

       27
       27
       +
       

     

       28
       28
       +
       let add_client t name =

     

       29
       29
       +
         let name = String.trim name in

     

       30
       30
       +
         let secret = Secret.generate () in

     

       31
       31
       +
         let hash = Secret.digest `SHA256 secret in

     

       32
       32
       +
         let name = pad_name name in

     

       33
       33
       +
         let store_secret = pad_name hash in

     

       34
       34
       +
         I.replace t name store_secret;

     

       35
       35
       +
         I.replace t store_secret name;

     

       36
       36
       +
         I.merge t;

     

       37
       37
       +
         secret

     

       38
       38
       +
       

     

       39
       39
       +
       let lookup t name =

     

       40
       40
       +
         let name = pad_name name in

     

       41
       41
       +
         try Some (I.find t name) with Not_found -> None

     

       42
       42
       +
       

     

       43
       43
       +
       let lookup_by_hash t digest =

     

       44
       44
       +
         try Some (I.find t (pad_name digest)) with Not_found -> None

     

       45
       45
       +
       

     

       46
       46
       +
       let remove t name =

     

       47
       47
       +
         let name = String.trim name in

     

       48
       48
       +
         let padded_name = pad_name name in

     

       49
       49
       +
         I.filter t (fun (k, _) -> k = padded_name);

     

       50
       50
       +
         I.merge t

     

       51
       51
       +
       

     

       52
       52
       +
       let list t =

     

       53
       53
       +
         let lst = ref [] in

     

       54
       54
       +
         I.iter (fun k _ -> lst := String.trim k :: !lst) t;

     

       55
       55
       +
         List.stable_sort String.compare !lst

     

       56
       56
       +
       

     

       57
       57
       +
       module type T = Capnp_rpc_net.Restorer.LOADER

     

       58
       58
       +
       

     

       59
       59
       +
       let hash _ = `SHA256

     

       60
       60
       +
       let make_sturdy t = t.make_sturdy

     

       61
       61
       +
       

     

       62
       62
       +
       let validate t digest () =

     

       63
       63
       +
         match lookup t.store digest with None -> false | Some _ -> true

     

       64
       64
       +
       

     

       65
       65
       +
       let load t self digest =

     

       66
       66
       +
         Logs.info (fun f -> f "Looking up %s" digest);

     

       67
       67
       +
         match lookup_by_hash t.store digest with

     

       68
       68
       +
         | None -> Capnp_rpc_net.Restorer.unknown_service_id

     

       69
       69
       +
         | Some _ ->

     

       70
       70
       +
             t.load ~validate:(validate t digest)

     

       71
       71
       +
               ~sturdy_ref:(Capnp_rpc.Sturdy_ref.cast self)