* gnu/system.scm (<operating-system>)[essential-services]: New field. (operating-system-directory-base-entries): Remove #:container? keyword and keep only the not-container branch. (essential-services): Likewise. (operating-system-services): Likewise, and call 'operating-system-essential-services' instead of 'essential-services'. (operating-system-activation-script): Remove #:container?. (operating-system-boot-script): Likewise. (operating-system-derivation): Likewise. * gnu/system/linux-container.scm (container-essential-services): New procedure. (containerized-operating-system): Use it and set the 'essential-services' field. (container-script): Remove call to 'operating-system-derivation'. * gnu/system/vm.scm (system-docker-image): Likewise. * doc/guix.texi (operating-system Reference): Document 'essential-services'.
		
			
				
	
	
		
			127 lines
		
	
	
	
		
			5.4 KiB
		
	
	
	
		
			Scheme
		
	
	
	
	
	
			
		
		
	
	
			127 lines
		
	
	
	
		
			5.4 KiB
		
	
	
	
		
			Scheme
		
	
	
	
	
	
;;; GNU Guix --- Functional package management for GNU
 | 
						|
;;; Copyright © 2015 David Thompson <davet@gnu.org>
 | 
						|
;;; Copyright © 2016, 2017, 2019 Ludovic Courtès <ludo@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 (guix modules)
 | 
						|
  #:use-module (gnu build linux-container)
 | 
						|
  #:use-module (gnu services)
 | 
						|
  #:use-module (gnu services base)
 | 
						|
  #:use-module (gnu services shepherd)
 | 
						|
  #:use-module (gnu system)
 | 
						|
  #:use-module (gnu system file-systems)
 | 
						|
  #:export (system-container
 | 
						|
            containerized-operating-system
 | 
						|
            container-script))
 | 
						|
 | 
						|
(define (container-essential-services os)
 | 
						|
  "Return a list of essential services corresponding to OS, a
 | 
						|
non-containerized OS.  This procedure essentially strips essential services
 | 
						|
from OS that are needed on the bare metal and not in a container."
 | 
						|
  (define base
 | 
						|
    (remove (lambda (service)
 | 
						|
              (memq (service-kind service)
 | 
						|
                    (list (service-kind %linux-bare-metal-service)
 | 
						|
                          firmware-service-type
 | 
						|
                          system-service-type)))
 | 
						|
            (operating-system-essential-services os)))
 | 
						|
 | 
						|
  (cons (service system-service-type
 | 
						|
                 (let ((locale (operating-system-locale-directory os)))
 | 
						|
                   (with-monad %store-monad
 | 
						|
                     (return `(("locale" ,locale))))))
 | 
						|
        (append base (list %containerized-shepherd-service))))
 | 
						|
 | 
						|
(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 (file-system-mapping->bind-mount fs))
 | 
						|
      (needed-for-boot? #t)))
 | 
						|
 | 
						|
  (define useless-services
 | 
						|
    ;; Services that make no sense in a container.  Those that attempt to
 | 
						|
    ;; access /dev/tty[0-9] in particular cannot work in a container.
 | 
						|
    (list console-font-service-type
 | 
						|
          mingetty-service-type
 | 
						|
          agetty-service-type))
 | 
						|
 | 
						|
  (operating-system
 | 
						|
    (inherit os)
 | 
						|
    (swap-devices '()) ; disable swap
 | 
						|
    (essential-services (container-essential-services os))
 | 
						|
    (services (remove (lambda (service)
 | 
						|
                        (memq (service-kind service)
 | 
						|
                              useless-services))
 | 
						|
                      (operating-system-user-services os)))
 | 
						|
    (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)))
 | 
						|
 | 
						|
    (define script
 | 
						|
      (with-imported-modules (source-module-closure
 | 
						|
                              '((guix build utils)
 | 
						|
                                (gnu build linux-container)))
 | 
						|
        #~(begin
 | 
						|
            (use-modules (gnu build linux-container)
 | 
						|
                         (gnu system file-systems) ;spec->file-system
 | 
						|
                         (guix build utils))
 | 
						|
 | 
						|
            (call-with-container (map spec->file-system '#$specs)
 | 
						|
              (lambda ()
 | 
						|
                (setenv "HOME" "/root")
 | 
						|
                (setenv "TMPDIR" "/tmp")
 | 
						|
                (setenv "GUIX_NEW_SYSTEM" #$os)
 | 
						|
                (for-each mkdir-p '("/run" "/bin" "/etc" "/home" "/var"))
 | 
						|
                (primitive-load (string-append #$os "/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)))
 |