;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2015 David Thompson <davet@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; ;;; GNU Guix is free software; you can redistribute it and/or modify it ;;; under the terms of the GNU General Public License as published by ;;; the Free Software Foundation; either version 3 of the License, or (at ;;; your option) any later version. ;;; ;;; GNU Guix is distributed in the hope that it will be useful, but ;;; WITHOUT ANY WARRANTY; without even the implied warranty of ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;;; GNU General Public License for more details. ;;; ;;; You should have received a copy of the GNU General Public License ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>. (define-module (gnu system linux-container) #:use-module (ice-9 match) #:use-module (srfi srfi-1) #:use-module (guix config) #:use-module (guix store) #:use-module (guix gexp) #:use-module (guix derivations) #:use-module (guix monads) #:use-module (gnu build linux-container) #:use-module (gnu services) #:use-module (gnu system) #:use-module (gnu system file-systems) #:export (mapping->file-system system-container containerized-operating-system container-script)) (define (mapping->file-system mapping) "Return a file system that realizes MAPPING." (match mapping (($ <file-system-mapping> source target writable?) (file-system (mount-point target) (device source) (type "none") (flags (if writable? '(bind-mount) '(bind-mount read-only))) (check? #f) (create-mount-point? #t))))) (define (containerized-operating-system os mappings) "Return an operating system based on OS for use in a Linux container environment. MAPPINGS is a list of <file-system-mapping> to realize in the containerized OS." (define user-file-systems (remove (lambda (fs) (let ((target (file-system-mount-point fs)) (source (file-system-device fs))) (or (string=? target (%store-prefix)) (string=? target "/") (and (string? source) (string-prefix? "/dev/" source)) (string-prefix? "/dev" target) (string-prefix? "/sys" target)))) (operating-system-file-systems os))) (define (mapping->fs fs) (file-system (inherit (mapping->file-system fs)) (needed-for-boot? #t))) (operating-system (inherit os) (swap-devices '()) ; disable swap (file-systems (append (map mapping->fs (cons %store-mapping mappings)) %container-file-systems user-file-systems)))) (define* (container-script os #:key (mappings '())) "Return a derivation of a script that runs OS as a Linux container. MAPPINGS is a list of <file-system> objects that specify the files/directories that will be shared with the host system." (let* ((os (containerized-operating-system os mappings)) (file-systems (filter file-system-needed-for-boot? (operating-system-file-systems os))) (specs (map file-system->spec file-systems))) (mlet* %store-monad ((os-drv (operating-system-derivation os #:container? #t))) (define script #~(begin (use-modules (gnu build linux-container) (guix build utils)) (call-with-container '#$specs (lambda () (setenv "HOME" "/root") (setenv "TMPDIR" "/tmp") (setenv "GUIX_NEW_SYSTEM" #$os-drv) (for-each mkdir-p '("/run" "/bin" "/etc" "/home" "/var")) (primitive-load (string-append #$os-drv "/boot"))) ;; A range of 65536 uid/gids is used to cover 16 bits worth of ;; users and groups, which is sufficient for most cases. ;; ;; See: http://www.freedesktop.org/software/systemd/man/systemd-nspawn.html#--private-users= #:host-uids 65536))) (gexp->script "run-container" script #:modules '((ice-9 match) (srfi srfi-98) (guix config) (guix utils) (guix build utils) (guix build syscalls) (guix build bournish) (gnu build file-systems) (gnu build linux-container))))))