guix-devel/guix/build/activation.scm

100 lines
3.6 KiB
Scheme

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014 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 (guix build activation)
#:use-module (guix build utils)
#:use-module (ice-9 ftw)
#:use-module (srfi srfi-26)
#:export (activate-etc
activate-setuid-programs))
;;; Commentary:
;;;
;;; This module provides "activation" helpers. Activation is the process that
;;; consists in setting up system-wide files and directories so that an
;;; 'operating-system' configuration becomes active.
;;;
;;; Code:
(define (activate-etc etc)
"Install ETC, a directory in the store, as the source of static files for
/etc."
;; /etc is a mixture of static and dynamic settings. Here is where we
;; initialize it from the static part.
(format #t "populating /etc from ~a...~%" etc)
(let ((rm-f (lambda (f)
(false-if-exception (delete-file f)))))
(rm-f "/etc/static")
(symlink etc "/etc/static")
(for-each (lambda (file)
;; TODO: Handle 'shadow' specially so that changed
;; password aren't lost.
(let ((target (string-append "/etc/" file))
(source (string-append "/etc/static/" file)))
(rm-f target)
(symlink source target)))
(scandir etc
(lambda (file)
(not (member file '("." ".."))))
;; The default is 'string-locale<?', but we don't have
;; it when run from the initrd's statically-linked
;; Guile.
string<?))
;; Prevent ETC from being GC'd.
(rm-f "/var/guix/gcroots/etc-directory")
(symlink etc "/var/guix/gcroots/etc-directory")))
(define %setuid-directory
;; Place where setuid programs are stored.
"/run/setuid-programs")
(define (activate-setuid-programs programs)
"Turn PROGRAMS, a list of file names, into setuid programs stored under
%SETUID-DIRECTORY."
(define (make-setuid-program prog)
(let ((target (string-append %setuid-directory
"/" (basename prog))))
(catch 'system-error
(lambda ()
(link prog target))
(lambda args
;; Perhaps PROG and TARGET live in a different file system, so copy
;; PROG.
(copy-file prog target)))
(chown target 0 0)
(chmod target #o6555)))
(format #t "setting up setuid programs in '~a'...~%"
%setuid-directory)
(if (file-exists? %setuid-directory)
(for-each (compose delete-file
(cut string-append %setuid-directory "/" <>))
(scandir %setuid-directory
(lambda (file)
(not (member file '("." ".."))))
string<?))
(mkdir-p %setuid-directory))
(for-each make-setuid-program programs))
;;; activation.scm ends here