guix/gnu/system.scm

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2015 Mark H Weaver <mhw@netris.org>
;;; Copyright © 2015, 2016 Alex Kost <alezost@gmail.com>
;;; Copyright © 2016 Chris Marusich <cmmarusich@gmail.com>
;;; Copyright © 2017 Mathieu Othacehe <m.othacehe@gmail.com>
;;; Copyright © 2019 Meiyo Peng <meiyo.peng@gmail.com>
;;; Copyright © 2020 Danny Milosavljevic <dannym@scratchpost.org>
;;; Copyright © 2020 Brice Waegeneire <brice@waegenei.re>
;;;
;;; 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)
  #:use-module (guix inferior)
  #:use-module (guix store)
  #:use-module (guix monads)
  #:use-module (guix gexp)
  #:use-module (guix records)
  #:use-module (guix packages)
  #:use-module (guix derivations)
  #:use-module (guix profiles)
  #:use-module (guix ui)
  #:use-module (guix utils)
  #:use-module (gnu packages base)
  #:use-module (gnu packages bash)
  #:use-module (gnu packages guile)
  #:use-module (gnu packages guile-xyz)
  #:use-module (gnu packages admin)
  #:use-module (gnu packages linux)
  #:use-module (gnu packages pciutils)
  #:use-module (gnu packages package-management)
  #:use-module (gnu packages less)
  #:use-module (gnu packages zile)
  #:use-module (gnu packages nano)
  #:use-module (gnu packages gawk)
  #:use-module (gnu packages man)
  #:use-module (gnu packages texinfo)
  #:use-module (gnu packages compression)
  #:use-module (gnu packages firmware)
  #:use-module (gnu services)
  #:use-module (gnu services shepherd)
  #:use-module (gnu services base)
  #:use-module (gnu bootloader)
  #:use-module (gnu system shadow)
  #:use-module (gnu system nss)
  #:use-module (gnu system locale)
  #:use-module (gnu system pam)
  #:use-module (gnu system linux-initrd)
  #:use-module (gnu system uuid)
  #:use-module (gnu system file-systems)
  #:use-module (gnu system mapped-devices)
  #:use-module (ice-9 match)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-35)
  #:use-module (rnrs bytevectors)
  #:export (operating-system
            operating-system?
            this-operating-system

            operating-system-bootloader
            operating-system-services
            operating-system-essential-services
            operating-system-default-essential-services
            operating-system-user-services
            operating-system-packages
            operating-system-host-name
            operating-system-hosts-file
            operating-system-kernel
            operating-system-kernel-file
            operating-system-kernel-arguments
            operating-system-label
            operating-system-default-label
            operating-system-initrd-modules
            operating-system-initrd
            operating-system-users
            operating-system-groups
            operating-system-issue
            operating-system-timezone
            operating-system-locale
            operating-system-locale-definitions
            operating-system-locale-libcs
            operating-system-mapped-devices
            operating-system-file-systems
            operating-system-store-file-system
            operating-system-user-mapped-devices
            operating-system-boot-mapped-devices
            operating-system-activation-script
            operating-system-user-accounts
            operating-system-shepherd-service-names
            operating-system-user-kernel-arguments
            operating-system-firmware
            operating-system-keyboard-layout
            operating-system-name-service-switch
            operating-system-pam-services
            operating-system-setuid-programs
            operating-system-skeletons
            operating-system-sudoers-file
            operating-system-swap-devices
            operating-system-kernel-loadable-modules

            operating-system-derivation
            operating-system-profile
            operating-system-bootcfg
            operating-system-etc-directory
            operating-system-locale-directory
            operating-system-boot-script

            system-linux-image-file-name
            operating-system-with-gc-roots
            operating-system-with-provenance

            boot-parameters
            boot-parameters?
            boot-parameters-label
            boot-parameters-root-device
            boot-parameters-bootloader-name
            boot-parameters-bootloader-menu-entries
            boot-parameters-store-device
            boot-parameters-store-mount-point
            boot-parameters-kernel
            boot-parameters-kernel-arguments
            boot-parameters-initrd
            read-boot-parameters
            read-boot-parameters-file
            boot-parameters->menu-entry

            local-host-aliases
            %root-account
            %setuid-programs
            %sudoers-specification
            %base-packages
            %base-packages-interactive
            %base-packages-linux
            %base-packages-networking
            %base-packages-utils
            %base-firmware))

;;; Commentary:
;;;
;;; This module supports whole-system configuration.
;;;
;;; Code:

(define (bootable-kernel-arguments system root-device)
  "Return a list of kernel arguments (gexps) to boot SYSTEM from ROOT-DEVICE."
  (list (string-append "--root="
                       ;; Note: Always use the DCE format because that's what
                       ;; (gnu build linux-boot) expects for the '--root'
                       ;; kernel command-line option.
                       (file-system-device->string root-device
                                                   #:uuid-type 'dce))
        #~(string-append "--system=" #$system)
        #~(string-append "--load=" #$system "/boot")))

;; System-wide configuration.
;; TODO: Add per-field docstrings/stexi.
(define-record-type* <operating-system> operating-system
  make-operating-system
  operating-system?
  this-operating-system

  (kernel operating-system-kernel                 ; package
          (default linux-libre))
  (kernel-loadable-modules operating-system-kernel-loadable-modules
                    (default '()))                ; list of packages
  (kernel-arguments operating-system-user-kernel-arguments
                    (default '("quiet")))         ; list of gexps/strings
  (bootloader operating-system-bootloader)        ; <bootloader-configuration>
  (label operating-system-label                   ; string
         (thunked)
         (default (operating-system-default-label this-operating-system)))

  (keyboard-layout operating-system-keyboard-layout ;#f | <keyboard-layout>
                   (default #f))
  (initrd operating-system-initrd                 ; (list fs) -> file-like
          (default base-initrd))
  (initrd-modules operating-system-initrd-modules ; list of strings
                  (thunked)                       ; it's system-dependent
                  (default %base-initrd-modules))

  (firmware operating-system-firmware             ; list of packages
            (default %base-firmware))

  (host-name operating-system-host-name)          ; string
  (hosts-file operating-system-hosts-file         ; file-like | #f
              (default #f))

  (mapped-devices operating-system-mapped-devices ; list of <mapped-device>
                  (default '()))
  (file-systems operating-system-file-systems)    ; list of fs
  (swap-devices operating-system-swap-devices     ; list of strings
                (default '()))

  (users operating-system-users                   ; list of user accounts
         (default %base-user-accounts))
  (groups operating-system-groups                 ; list of user groups
          (default %base-groups))

  (skeletons operating-system-skeletons           ; list of name/file-like value
             (default (default-skeletons)))
  (issue operating-system-issue                   ; string
         (default %default-issue))

  (packages operating-system-packages             ; list of (PACKAGE OUTPUT...)
            (default %base-packages))             ; or just PACKAGE

  (timezone operating-system-timezone)            ; string
  (locale   operating-system-locale               ; string
            (default "en_US.utf8"))
  (locale-definitions operating-system-locale-definitions ; list of <locale-definition>
                      (default %default-locale-definitions))
  (locale-libcs operating-system-locale-libcs     ; list of <packages>
                (default %default-locale-libcs))
  (name-service-switch operating-system-name-service-switch ; <name-service-switch>
                       (default %default-nss))

  (essential-services operating-system-essential-services ; list of services
                      (thunked)
                      (default (operating-system-default-essential-services
                                this-operating-system)))
  (services operating-system-user-services        ; list of services
            (default %base-services))

  (pam-services operating-system-pam-services     ; list of PAM services
                (default (base-pam-services)))
  (setuid-programs operating-system-setuid-programs
                   (default %setuid-programs))    ; list of string-valued gexps

  (sudoers-file operating-system-sudoers-file     ; file-like
                (default %sudoers-specification)))

(define (operating-system-kernel-arguments os root-device)
  "Return all the kernel arguments, including the ones not specified
directly by the user."
  (append (bootable-kernel-arguments os root-device)
          (operating-system-user-kernel-arguments os)))


;;;
;;; Boot parameters
;;;

(define-record-type* <boot-parameters>
  boot-parameters make-boot-parameters boot-parameters?
  (label            boot-parameters-label)
  ;; Because we will use the 'store-device' to create the GRUB search command,
  ;; the 'store-device' has slightly different semantics than 'root-device'.
  ;; The 'store-device' can be a file system uuid, a file system label, or #f,
  ;; but it cannot be a device path such as "/dev/sda3", since GRUB would not
  ;; understand that.  The 'root-device', on the other hand, corresponds
  ;; exactly to the device field of the <file-system> object representing the
  ;; OS's root file system, so it might be a device path like "/dev/sda3".
  (root-device      boot-parameters-root-device)
  (bootloader-name  boot-parameters-bootloader-name)
  (bootloader-menu-entries                        ;list of <menu-entry>
   boot-parameters-bootloader-menu-entries)
  (store-device     boot-parameters-store-device)
  (store-mount-point boot-parameters-store-mount-point)
  (kernel           boot-parameters-kernel)
  (kernel-arguments boot-parameters-kernel-arguments)
  (initrd           boot-parameters-initrd))

(define (ensure-not-/dev device)
  "If DEVICE starts with a slash, return #f.  This is meant to filter out
Linux device names such as /dev/sda, and to preserve GRUB device names and
file system labels."
  (if (and (string? device) (string-prefix? "/" device))
      #f
      device))

(define (read-boot-parameters port)
  "Read boot parameters from PORT and return the corresponding
<boot-parameters> object or #f if the format is unrecognized."
  (define device-sexp->device
    (match-lambda
      (('uuid (? symbol? type) (? bytevector? bv))
       (bytevector->uuid bv type))
      (('file-system-label (? string? label))
       (file-system-label label))
      ((? bytevector? bv)                         ;old format
       (bytevector->uuid bv 'dce))
      ((? string? device)
       ;; It used to be that we would not distinguish between labels and
       ;; device names.  Try to infer the right thing here.
       (if (string-prefix? "/dev/" device)
           device
           (file-system-label device)))))

  (match (read port)
    (('boot-parameters ('version 0)
                       ('label label) ('root-device root)
                       ('kernel linux)
                       rest ...)
     (boot-parameters
      (label label)
      (root-device (device-sexp->device root))

      (bootloader-name
       (match (assq 'bootloader-name rest)
         ((_ args) args)
         (#f       'grub))) ; for compatibility reasons.

      (bootloader-menu-entries
       (match (assq 'bootloader-menu-entries rest)
         ((_ entries) (map sexp->menu-entry entries))
         (#f          '())))

      ;; In the past, we would store the directory name of the kernel instead
      ;; of the absolute file name of its image.  Detect that and correct it.
      (kernel (if (string=? linux (direct-store-path linux))
                  (string-append linux "/"
                                 (system-linux-image-file-name))
                  linux))

      (kernel-arguments
       (match (assq 'kernel-arguments rest)
         ((_ args) args)
         (#f       '())))                         ;the old format

      (initrd
       (match (assq 'initrd rest)
         (('initrd ('string-append directory file)) ;the old format
          (string-append directory file))
         (('initrd (? string? file))
          file)))

      (store-device
       ;; Linux device names like "/dev/sda1" are not suitable GRUB device
       ;; identifiers, so we just filter them out.
       (ensure-not-/dev
        (match (assq 'store rest)
          (('store ('device #f) _ ...)
           root-device)
          (('store ('device device) _ ...)
           (device-sexp->device device))
          (_                                      ;the old format
           root-device))))

      (store-mount-point
       (match (assq 'store rest)
         (('store ('device _) ('mount-point mount-point) _ ...)
          mount-point)
         (_                                       ;the old format
          "/")))))
    (x                                            ;unsupported format
     (warning (G_ "unrecognized boot parameters at '~a'~%")
              (port-filename port))
     #f)))

(define (read-boot-parameters-file system)
  "Read boot parameters from SYSTEM's (system or generation) \"parameters\"
file and returns the corresponding <boot-parameters> object or #f if the
format is unrecognized.
The object has its kernel-arguments extended in order to make it bootable."
  (let* ((file (string-append system "/parameters"))
         (params (call-with-input-file file read-boot-parameters))
         (root (boot-parameters-root-device params)))
    (boot-parameters
     (inherit params)
     (kernel-arguments (append (bootable-kernel-arguments system root)
                               (boot-parameters-kernel-arguments params))))))

(define (boot-parameters->menu-entry conf)
  (menu-entry
   (label (boot-parameters-label conf))
   (device (boot-parameters-store-device conf))
   (device-mount-point (boot-parameters-store-mount-point conf))
   (linux (boot-parameters-kernel conf))
   (linux-arguments (boot-parameters-kernel-arguments conf))
   (initrd (boot-parameters-initrd conf))))



;;;
;;; Services.
;;;

(define (non-boot-file-system-service os)
  "Return the file system service for the file systems of OS that are not
marked as 'needed-for-boot'."
  (define file-systems
    (remove file-system-needed-for-boot?
            (operating-system-file-systems os)))

  (define mapped-devices-for-boot
    (operating-system-boot-mapped-devices os))

  (define (device-mappings fs)
    (let ((device (file-system-device fs)))
      (if (string? device)                        ;title is 'device
          (filter (lambda (md)
                    (string=? (string-append "/dev/mapper/"
                                             (mapped-device-target md))
                              device))
                  (operating-system-mapped-devices os))
          '())))

  (define (add-dependencies fs)
    ;; Add the dependencies due to device mappings to FS.
    (file-system
      (inherit fs)
      (dependencies
       (delete-duplicates
        (remove (cut member <> mapped-devices-for-boot)
                (append (device-mappings fs)
                        (file-system-dependencies fs)))
        eq?))))

  (service file-system-service-type
           (map add-dependencies file-systems)))

(define (mapped-device-users device file-systems)
  "Return the subset of FILE-SYSTEMS that use DEVICE."
  (let ((target (string-append "/dev/mapper/" (mapped-device-target device))))
    (filter (lambda (fs)
              (or (member device (file-system-dependencies fs))
                  (and (string? (file-system-device fs))
                       (string=? (file-system-device fs) target))))
            file-systems)))

(define (operating-system-user-mapped-devices os)
  "Return the subset of mapped devices that can be installed in
user-land--i.e., those not needed during boot."
  (let ((devices      (operating-system-mapped-devices os))
        (file-systems (operating-system-file-systems os)))
   (filter (lambda (md)
             (let ((users (mapped-device-users md file-systems)))
               (not (any file-system-needed-for-boot? users))))
           devices)))

(define (operating-system-boot-mapped-devices os)
  "Return the subset of mapped devices that must be installed during boot,
from the initrd."
  (let ((devices      (operating-system-mapped-devices os))
        (file-systems (operating-system-file-systems os)))
   (filter (lambda (md)
             (let ((users (mapped-device-users md file-systems)))
               (any file-system-needed-for-boot? users)))
           devices)))

(define (device-mapping-services os)
  "Return the list of device-mapping services for OS as a list."
  (map device-mapping-service
       (operating-system-user-mapped-devices os)))

(define (swap-services os)
  "Return the list of swap services for OS."
  (map swap-service (operating-system-swap-devices os)))

(define* (system-linux-image-file-name)
  "Return the basename of the kernel image file for SYSTEM."
  ;; FIXME: Evaluate the conditional based on the actual current system.
  (let ((target (or (%current-target-system) (%current-system))))
    (cond
     ((string-prefix? "arm" target) "zImage")
     ((string-prefix? "mips" target) "vmlinuz")
     ((string-prefix? "aarch64" target) "Image")
     (else "bzImage"))))

(define (operating-system-kernel-file os)
  "Return an object representing the absolute file name of the kernel image of
OS."
  (file-append (operating-system-kernel os)
               "/" (system-linux-image-file-name)))

(define (package-for-kernel target-kernel module-package)
  "Return a package like MODULE-PACKAGE, adapted for TARGET-KERNEL, if
possible (that is if there's a LINUX keyword argument in the build system)."
  (package
    (inherit module-package)
    (arguments
     (substitute-keyword-arguments (package-arguments module-package)
       ((#:linux kernel #f)
        target-kernel)))))

(define* (operating-system-directory-base-entries os)
  "Return the basic entries of the 'system' directory of OS for use as the
value of the SYSTEM-SERVICE-TYPE service."
  (let ((locale (operating-system-locale-directory os)))
    (mlet* %store-monad ((kernel -> (operating-system-kernel os))
                         (modules ->
                          (operating-system-kernel-loadable-modules os))
                         (kernel
                          (profile-derivation
                           (packages->manifest
                            (cons kernel
                             (map (lambda (module)
                                    (if (package? module)
                                        (package-for-kernel kernel module)
                                        module))
                                  modules)))
                           #:hooks (list linux-module-database)))
                         (initrd -> (operating-system-initrd-file os))
                         (params -> (operating-system-boot-parameters-file os)))
      (return `(("kernel" ,kernel)
                ("parameters" ,params)
                ("initrd" ,initrd)
                ("locale" ,locale))))))   ;used by libc

(define (operating-system-default-essential-services os)
  "Return the list of essential services for OS.  These are special services
that implement part of what's declared in OS are responsible for low-level
bookkeeping."
  (define known-fs
    (map file-system-mount-point (operating-system-file-systems os)))

  (let* ((mappings  (device-mapping-services os))
         (root-fs   (root-file-system-service))
         (other-fs  (non-boot-file-system-service os))
         (swaps     (swap-services os))
         (procs     (service user-processes-service-type))