code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2016 David Craven <david@craven.ch>
;;; Copyright © 2016 Julien Lepiller <julien@lepiller.eu>
;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
;;; Copyright © 2020 pinoaffe <pinoaffe@airmail.cc>
;;;
;;; 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 services ssh)
  #:use-module (gnu packages ssh)
  #:use-module (gnu packages admin)
  #:use-module (gnu services)
  #:use-module (gnu services shepherd)
  #:use-module (gnu system pam)
  #:use-module (gnu system shadow)
  #:use-module (guix gexp)
  #:use-module (guix records)
  #:use-module (guix modules)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 match)
  #:export (lsh-configuration
            lsh-configuration?
            lsh-service
            lsh-service-type

            openssh-configuration
            openssh-configuration?
            openssh-service-type

            dropbear-configuration
            dropbear-configuration?
            dropbear-service-type
            dropbear-service

            autossh-configuration
            autossh-configuration?
            autossh-service-type))

;;; Commentary:
;;;
;;; This module implements secure shell (SSH) services.
;;;
;;; Code:

(define-record-type* <lsh-configuration>
  lsh-configuration make-lsh-configuration
  lsh-configuration?
  (lsh lsh-configuration-lsh
       (default lsh))
  (daemonic? lsh-configuration-daemonic?)
  (host-key lsh-configuration-host-key)
  (interfaces lsh-configuration-interfaces)
  (port-number lsh-configuration-port-number)
  (allow-empty-passwords? lsh-configuration-allow-empty-passwords?)
  (root-login? lsh-configuration-root-login?)
  (syslog-output? lsh-configuration-syslog-output?)
  (pid-file? lsh-configuration-pid-file?)
  (pid-file lsh-configuration-pid-file)
  (x11-forwarding? lsh-configuration-x11-forwarding?)
  (tcp/ip-forwarding? lsh-configuration-tcp/ip-forwarding?)
  (password-authentication? lsh-configuration-password-authentication?)
  (public-key-authentication? lsh-configuration-public-key-authentication?)
  (initialize? lsh-configuration-initialize?))

(define %yarrow-seed
  "/var/spool/lsh/yarrow-seed-file")

(define (lsh-initialization lsh host-key)
  "Return the gexp to initialize the LSH service for HOST-KEY."
  #~(begin
      (unless (file-exists? #$%yarrow-seed)
        (system* (string-append #$lsh "/bin/lsh-make-seed")
                 "--sloppy" "-o" #$%yarrow-seed))

      (unless (file-exists? #$host-key)
        (mkdir-p (dirname #$host-key))
        (format #t "creating SSH host key '~a'...~%" #$host-key)

        ;; FIXME: We're just doing a simple pipeline, but 'system' cannot be
        ;; used yet because /bin/sh might be dangling; factorize this somehow.
        (let* ((in+out (pipe))
               (keygen (primitive-fork)))
          (case keygen
            ((0)
             (close-port (car in+out))
             (close-fdes 1)
             (dup2 (fileno (cdr in+out)) 1)
             (execl (string-append #$lsh "/bin/lsh-keygen")
                    "lsh-keygen" "--server"))
            (else
             (let ((write-key (primitive-fork)))
               (case write-key
                 ((0)
                  (close-port (cdr in+out))
                  (close-fdes 0)
                  (dup2 (fileno (car in+out)) 0)
                  (execl (string-append #$lsh "/bin/lsh-writekey")
                         "lsh-writekey" "--server" "-o" #$host-key))
                 (else
                  (close-port (car in+out))
                  (close-port (cdr in+out))
                  (waitpid keygen)
                  (waitpid write-key))))))))))

(define (lsh-activation config)
  "Return the activation gexp for CONFIG."
  #~(begin
      (use-modules (guix build utils))
      (mkdir-p "/var/spool/lsh")
      #$(if (lsh-configuration-initialize? config)
            (lsh-initialization (lsh-configuration-lsh config)
                                (lsh-configuration-host-key config))
            #t)))

(define (lsh-shepherd-service config)
  "Return a <shepherd-service> for lsh with CONFIG."
  (define lsh (lsh-configuration-lsh config))
  (define pid-file (lsh-configuration-pid-file config))
  (define pid-file? (lsh-configuration-pid-file? config))
  (define daemonic? (lsh-configuration-daemonic? config))
  (define interfaces (lsh-configuration-interfaces config))

  (define lsh-command
    (append
     (cons (file-append lsh "/sbin/lshd")
           (if daemonic?
               (let ((syslog (if (lsh-configuration-syslog-output? config)
                                 '()
                                 (list "--no-syslog"))))
                 (cons "--daemonic"
                       (if pid-file?
                           (cons #~(string-append "--pid-file=" #$pid-file)
                                 syslog)
                           (cons "--no-pid-file" syslog))))
               (if pid-file?
                   (list #~(string-append "--pid-file=" #$pid-file))
                   '())))
     (cons* #~(string-append "--host-key="
                             #$(lsh-configuration-host-key config))
            #~(string-append "--password-helper=" #$lsh "/sbin/lsh-pam-checkpw")
            #~(string-append "--subsystems=sftp=" #$lsh "/sbin/sftp-server")
            "-p" (number->string (lsh-configuration-port-number config))
            (if (lsh-configuration-password-authentication? config)
                "--password" "--no-password")
            (if (lsh-configuration-public-key-authentication? config)
                "--publickey" "--no-publickey")
            (if (lsh-configuration-root-login? config)
                "--root-login" "--no-root-login")
            (if (lsh-configuration-x11-forwarding? config)
                "--x11-forward" "--no-x11-forward")
            (if (lsh-configuration-tcp/ip-forwarding? config)
                "--tcpip-forward" "--no-tcpip-forward")
            (if (null? interfaces)
                '()
                (map (cut string-append "--interface=" <>)
                     interfaces)))))

  (define requires
    (if (and daemonic? (lsh-configuration-syslog-output? config))
        '(networking syslogd)
        '(networking)))

  (list (shepherd-service
         (documentation "GNU lsh SSH server")
         (provision '(ssh-daemon ssh sshd))
         (requirement requires)
         (start #~(make-forkexec-constructor (list #$@lsh-command)))
         (stop  #~(make-kill-destructor)))))

(define (lsh-pam-services config)
  "Return a list of <pam-services> for lshd with CONFIG."
  (list (unix-pam-service
         "lshd"
         #:login-uid? #t
         #:allow-empty-passwords?
         (lsh-configuration-allow-empty-passwords? config))))

(define lsh-service-type
  (service-type (name 'lsh)
                (description
                 "Run the GNU@tie{}lsh secure shell (SSH) daemon,
@command{lshd}.")
                (extensions
                 (list (service-extension shepherd-root-service-type
                                          lsh-shepherd-service)
                       (service-extension pam-root-service-type
                                          lsh-pam-services)
                       (service-extension activation-service-type
                                          lsh-activation)))))

(define* (lsh-service #:key
                      (lsh lsh)
                      (daemonic? #t)
                      (host-key "/etc/lsh/host-key")
                      (interfaces '())
                      (port-number 22)
                      (allow-empty-passwords? #f)
                      (root-login? #f)
                      (syslog-output? #t)
                      (pid-file? #f)
                      (pid-file "/var/run/lshd.pid")
                      (x11-forwarding? #t)
                      (tcp/ip-forwarding? #t)
                      (password-authentication? #t)
                      (public-key-authentication? #t)
                      (initialize? #t))
  "Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
@var{host-key} must designate a file containing the host key, and readable
only by root.

When @var{daemonic?} is true, @command{lshd} will detach from the
controlling terminal and log its output to syslogd, unless one sets
@var{syslog-output?} to false.  Obviously, it also makes lsh-service
depend on existence of syslogd service.  When @var{pid-file?} is true,
@command{lshd} writes its PID to the file called @var{pid-file}.

When @var{initialize?} is true, automatically create the seed and host key
upon service activation if they do not exist yet.  This may take long and
require interaction.

When @var{initialize?} is false, it is up to the user to initialize the
randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
a key pair with the private key stored in file @var{host-key} (@pxref{lshd
basics,,, lsh, LSH Manual}).

When @var{interfaces} is empty, lshd listens for connections on all the
network interfaces; otherwise, @var{interfaces} must be a list of host names
or addresses.

@var{allow-empty-passwords?} specifies whether to accept log-ins with empty
passwords, and @var{root-login?} specifies whether to accept log-ins as
root.

The other options should be self-descriptive."
  (service lsh-service-type
           (lsh-configuration (lsh lsh) (daemonic? daemonic?)
                              (host-key host-key) (interfaces interfaces)
                              (port-number port-number)
                              (allow-empty-passwords? allow-empty-passwords?)
                              (root-login? root-login?)
                              (syslog-output? syslog-output?)
                              (pid-file? pid-file?) (pid-file pid-file)
                              (x11-forwarding? x11-forwarding?)
                              (tcp/ip-forwarding? tcp/ip-forwarding?)
                              (password-authentication?
                               password-authentication?)
                              (public-key-authentication?
                               public-key-authentication?)
                              (initialize? initialize?))))

;;;
;;; OpenSSH.
;;;

(define-record-type* <openssh-configuration>
  openssh-configuration make-openssh-configuration
  openssh-configuration?
  ;; <package>
  (openssh               openssh-configuration-openssh
                         (default openssh))
  ;; string
  (pid-file              openssh-configuration-pid-file
                         (default "/var/run/sshd.pid"))
  ;; integer
  (port-number           openssh-configuration-port-number
                         (default 22))
  ;; Boolean | 'without-password
  (permit-root-login     openssh-configuration-permit-root-login
                         (default #f))
  ;; Boolean
  (allow-empty-passwords? openssh-configuration-allow-empty-passwords?
                          (default #f))
  ;; Boolean
  (password-authentication? openssh-configuration-password-authentication?
                            (default #t))
  ;; Boolean
  (public-key-authentication? openssh-configuration-public-key-authentication?
                              (default #t))
  ;; Boolean
  (x11-forwarding?       openssh-configuration-x11-forwarding?
                         (default #f))

  ;; Boolean
  (allow-agent-forwarding? openssh-configuration-allow-agent-forwarding?
                           (default #t))

  ;; Boolean
  (allow-tcp-forwarding? openssh-configuration-allow-tcp-forwarding?
                         (default #t))

  ;; Boolean
  (gateway-ports? openssh-configuration-gateway-ports?
                         (default #f))

  ;; Boolean
  (challenge-response-authentication? openssh-challenge-response-authentication?
                                      (default #f))
  ;; Boolean
  (use-pam?              openssh-configuration-use-pam?
                         (default #t))
  ;; Boolean
  (print-last-log?       openssh-configuration-print-last-log?
                         (default #t))
  ;; list of two-element lists
  (subsystems            openssh-configuration-subsystems
                         (default '(("sftp" "internal-sftp"))))

  ;; list of strings
  (accepted-environment  openssh-configuration-accepted-environment
                         (default '()))

  ;; symbol
  (log-level             openssh-configuration-log-level
                         (default 'info))

  ;; String
  ;; This is an "escape hatch" to provide configuration that isn't yet
  ;; supported by this configuration record.
  (extra-content         openssh-configuration-extra-content
                         (default ""))

  ;; list of user-name/file-like tuples
  (authorized-keys       openssh-authorized-keys
                         (default '()))

  ;; Boolean
  ;; XXX: This should really be handled in an orthogonal way, for instance as
  ;; proposed in <https://bugs.gnu.org/27155>.  Keep it internal/undocumented
  ;; for now.
  (%auto-start?          openssh-auto-start?
                         (default #t)))

(define %openssh-accounts
  (list (user-group (name "sshd") (system? #t))
        (user-account
          (name "sshd")
          (group "sshd")
          (system? #t)
          (comment "sshd privilege separation user")
          (home-directory "/var/run/sshd")
          (shell (file-append shadow "/sbin/nologin")))))

(define (openssh-activation config)
  "Return the activation GEXP for CONFIG."
  (with-imported-modules '((guix build utils))
    #~(begin
        (use-modules (guix build utils))

        (define (touch file-name)
          (call-with-output-file file-name (const #t)))

        ;; Make sure /etc/ssh can be read by the 'sshd' user.
        (mkdir-p "/etc/ssh")
        (chmod "/etc/ssh" #o755)
        (mkdir-p (dirname #$(openssh-configuration-pid-file config)))

        ;; 'sshd' complains if the authorized-key directory and its parents
        ;; are group-writable, which rules out /gnu/store.  Thus we copy the
        ;; authorized-key directory to /etc.
        (catch 'system-error
          (lambda ()
            (delete-file-recursively "/etc/authorized_keys.d"))
          (lambda args
            (unless (= ENOENT (system-error-errno args))
              (apply throw args))))
        (copy-recursively #$(authorized-key-directory
                             (openssh-authorized-keys config))
                          "/etc/ssh/authorized_keys.d")

        (chmod "/etc/ssh/authorized_keys.d" #o555)

        (let ((lastlog "/var/log/lastlog"))
          (when #$(openssh-configuration-print-last-log? config)
            (unless (file-exists? lastlog)
              (touch lastlog))))

        ;; Generate missing host keys.
        (system* (string-append #$(openssh-configuration-openssh config)
                                "/bin/ssh-keygen") "-A"))))

(define (authorized-key-directory keys)
  "Return a directory containing the authorized keys specified in KEYS, a list
of user-name/file-like tuples."
  (define build
    (with-imported-modules (source-module-closure '((guix build utils)))
      #~(begin
          (use-modules (ice-9 match) (srfi srfi-26)
                       (guix build utils))

          (mkdir #$output)
          (for-each (match-lambda
                      ((user keys ...)
                       (let ((file (string-append #$output "/" user)))
                         (call-with-output-file file
                           (lambda (port)
                             (for-each (lambda (key)
                                         (call-with-input-file key
                                           (cut dump-port <> port)))
                                       keys))))))
                    '#$keys))))

  (computed-file "openssh-authorized-keys" build))

(define (openssh-config-file config)
  "Return the sshd configuration file corresponding to CONFIG."
  (computed-file
   "sshd_config"
   #~(begin
       (use-modules (ice-9 match))
       (call-with-output-file #$output
         (lambda (port)
           (display "# Generated by 'openssh-service'.\n" port)
           (format port "Port ~a\n"
                   #$(number->string
                      (openssh-configuration-port-number config)))
           (format port "PermitRootLogin ~a\n"
                   #$(match (openssh-configuration-permit-root-login config)
                       (#t "yes")
                       (#f "no")
                       ('without-password "without-password")))
           (format port "PermitEmptyPasswords ~a\n"
                   #$(if (openssh-configuration-allow-empty-passwords? config)
                         "yes" "no"))
           (format port "PasswordAuthentication ~a\n"
                   #$(if (openssh-configuration-password-authentication? config)
                         "yes" "no"))
           (format port "PubkeyAuthentication ~a\n"
                   #$(if (openssh-configuration-public-key-authentication?
                          config)
                         "yes" "no"))
           (format port "X11Forwarding ~a\n"
                   #$(if (openssh-configuration-x11-forwarding? config)
                         "yes" "no"))
           (format port "AllowAgentForwarding ~a\n"
                   #$(if (openssh-configuration-allow-agent-forwarding? config)
                         "yes" "no"))
           (format port "AllowTcpForwarding ~a\n"
                   #$(if (openssh-configuration-allow-tcp-forwarding? config)
                         "yes" "no"))
           (format port "GatewayPorts ~a\n"
                   #$(if (openssh-configuration-gateway-ports? config)
                         "yes" "no"))
           (format port "PidFile ~a\n"
                   #$(openssh-configuration-pid-file config))
           (format port "ChallengeResponseAuthentication ~a\n"
                   #$(if (openssh-challenge-response-authentication? config)
                         "yes" "no"))
           (format port "UsePAM ~a\n"
                   #$(if (openssh-configuration-use-pam? config)
                         "yes" "no"))
           (format port "PrintLastLog ~a\n"
                   #$(if (openssh-configuration-print-last-log? config)
                         "yes" "no"))
           (format port "LogLevel ~a\n"
                   #$(string-upcase
                      (symbol->string
                       (openssh-configuration-log-level config))))

           ;; Add '/etc/authorized_keys.d/%u', which we populate.
           (format port "AuthorizedKeysFile \
 .ssh/authorized_keys .ssh/authorized_keys2 /etc/ssh/authorized_keys.d/%u\n")

           (for-each (lambda (s) (format port "AcceptEnv ~a\n" s))
                     '#$(openssh-configuration-accepted-environment config))

           (for-each
            (match-lambda
              ((name command) (format port "Subsystem\t~a\t~a\n" name command)))
            '#$(openssh-configuration-subsystems config))

           (format port "~a\n"
                   #$(openssh-configuration-extra-content config))
           #t)))))

(define (openssh-shepherd-service config)
  "Return a <shepherd-service> for openssh with CONFIG."

  (define pid-file
    (openssh-configuration-pid-file config))

  (define openssh-command
    #~(list (string-append #$(openssh-configuration-openssh config) "/sbin/sshd")
            "-D" "-f" #$(openssh-config-file config)))

  (list (shepherd-service
         (documentation "OpenSSH server.")
         (requirement '(syslogd loopback))
         (provision '(ssh-daemon ssh sshd))
         (start #~(make-forkexec-constructor #$openssh-command
                                             #:pid-file #$pid-file))
         (stop #~(make-kill-destructor))
         (auto-start? (openssh-auto-start? config)))))

(define (openssh-pam-services config)
  "Return a list of <pam-services> for sshd with CONFIG."
  (list (unix-pam-service
         "sshd"
         #:login-uid? #t
         #:allow-empty-passwords?
         (openssh-configuration-allow-empty-passwords? config))))

(define (extend-openssh-authorized-keys config keys)
  "Extend CONFIG with the extra authorized keys listed in KEYS."
  (openssh-configuration
   (inherit config)
   (authorized-keys
    (append (openssh-authorized-keys config) keys))))

(define openssh-service-type
  (service-type (name 'openssh)
                (description
                 "Run the OpenSSH secure shell (SSH) server, @command{sshd}.")
                (extensions
                 (list (service-extension shepherd-root-service-type
                                          openssh-shepherd-service)
                       (service-extension pam-root-service-type
                                          openssh-pam-services)
                       (service-extension activation-service-type
                                          openssh-activation)
                       (service-extension account-service-type
                                          (const %openssh-accounts))

                       ;; Install OpenSSH in the system profile.  That way,
                       ;; 'scp' is found when someone tries to copy to or from
                       ;; this machine.
                       (service-extension profile-service-type
                                          (lambda (config)
                                            (list (openssh-configuration-openssh
                                                   config))))))
                (compose concatenate)
                (extend extend-openssh-authorized-keys)
                (default-value (openssh-configuration))))

;;;
;;; Dropbear.
;;;

(define-record-type* <dropbear-configuration>
  dropbear-configuration make-dropbear-configuration
  dropbear-configuration?
  (dropbear               dropbear-configuration-dropbear
                          (default dropbear))
  (port-number            dropbear-configuration-port-number
                          (default 22))
  (syslog-output?         dropbear-configuration-syslog-output?
                          (default #t))
  (pid-file               dropbear-configuration-pid-file
                          (default "/var/run/dropbear.pid"))
  (root-login?            dropbear-configuration-root-login?
                          (default #f))
  (allow-empty-passwords? dropbear-configuration-allow-empty-passwords?
                          (default #f))
  (password-authentication? dropbear-configuration-password-authentication?
                            (default #t)))

(define (dropbear-activation config)
  "Return the activation gexp for CONFIG."
  #~(begin
      (use-modules (guix build utils))
      (mkdir-p "/etc/dropbear")))

(define (dropbear-shepherd-service config)
  "Return a <shepherd-service> for dropbear with CONFIG."
  (define dropbear
    (dropbear-configuration-dropbear config))

  (define pid-file
    (dropbear-configuration-pid-file config))

  (define dropbear-command
    #~(list (string-append #$dropbear "/sbin/dropbear")

            ;; '-R' allows host keys to be automatically generated upon first
            ;; connection, at a time when /dev/urandom is more likely securely
            ;; seeded.
            "-F" "-R"

            "-p" #$(number->string (dropbear-configuration-port-number config))
            "-P" #$pid-file
            #$@(if (dropbear-configuration-syslog-output? config) '() '("-E"))
            #$@(if (dropbear-configuration-root-login? config) '() '("-w"))
            #$@(if (dropbear-configuration-password-authentication? config)
                   '()
                   '("-s" "-g"))
            #$@(if (dropbear-configuration-allow-empty-passwords? config)
                   '("-B")
                   '())))

  (define requires
    (if (dropbear-configuration-syslog-output? config)
        '(networking syslogd) '(networking)))

  (list (shepherd-service
         (documentation "Dropbear SSH server.")
         (requirement requires)
         (provision '(ssh-daemon ssh sshd))
         (start #~(make-forkexec-constructor #$dropbear-command
                                             #:pid-file #$pid-file))
         (stop #~(make-kill-destructor)))))

(define dropbear-service-type
  (service-type (name 'dropbear)
                (description
                 "Run the Dropbear secure shell (SSH) server.")
                (extensions
                 (list (service-extension shepherd-root-service-type
                                          dropbear-shepherd-service)
                       (service-extension activation-service-type
                                          dropbear-activation)))
                (default-value (dropbear-configuration))))

(define* (dropbear-service #:optional (config (dropbear-configuration)))
  "Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
daemon} with the given @var{config}, a @code{<dropbear-configuration>}
object."
  (service dropbear-service-type config))

;;;
;;; AutoSSH.
;;;

(define-record-type* <autossh-configuration>
  autossh-configuration make-autossh-configuration
  autossh-configuration?
  (user            autossh-configuration-user
                   (default "autossh"))
  (poll            autossh-configuration-poll
                   (default 600))
  (first-poll      autossh-configuration-first-poll
                   (default #f))
  (gate-time       autossh-configuration-gate-time
                   (default 30))
  (log-level       autossh-configuration-log-level
                   (default 1))
  (max-start       autossh-configuration-max-start
                   (default #f))
  (message         autossh-configuration-message
                   (default ""))
  (port            autossh-configuration-port
                   (default "0"))
  (ssh-options     autossh-configuration-ssh-options
                   (default '())))

(define (autossh-file-name config file)
  "Return a path in /var/run/autossh/ that is writable
   by @code{user} from @code{config}."
  (string-append "/var/run/autossh/"
                 (autossh-configuration-user config)
                 "/" file))

(define (autossh-shepherd-service config)
  (shepherd-service
   (documentation "Automatically set up ssh connections (and keep them alive).")
   (provision '(autossh))
   (start #~(make-forkexec-constructor
             (list #$(file-append autossh "/bin/autossh")
                   #$@(autossh-configuration-ssh-options config))
             #:user #$(autossh-configuration-user config)
             #:group (passwd:gid (getpw #$(autossh-configuration-user config)))
             #:pid-file #$(autossh-file-name config "pid")
             #:log-file #$(autossh-file-name config "log")
             #:environment-variables
             '(#$(string-append "AUTOSSH_PIDFILE="
                                (autossh-file-name config "pid"))
               #$(string-append "AUTOSSH_LOGFILE="
                                (autossh-file-name config "log"))
               #$(string-append "AUTOSSH_POLL="
                                (number->string
                                 (autossh-configuration-poll config)))
               #$(string-append "AUTOSSH_FIRST_POLL="
                                (number->string
                                 (or
                                  (autossh-configuration-first-poll config)
                                  (autossh-configuration-poll config))))
               #$(string-append "AUTOSSH_GATETIME="
                                (number->string
                                 (autossh-configuration-gate-time config)))
               #$(string-append "AUTOSSH_LOGLEVEL="
                                (number->string
                                 (autossh-configuration-log-level config)))
               #$(string-append "AUTOSSH_MAXSTART="
                                (number->string
                                 (or (autossh-configuration-max-start config)
                                     -1)))
               #$(string-append "AUTOSSH_MESSAGE="
                                (autossh-configuration-message config))
               #$(string-append "AUTOSSH_PORT="
                                (autossh-configuration-port config)))))
   (stop #~(make-kill-destructor))))

(define (autossh-service-activation config)
  (with-imported-modules '((guix build utils))
    #~(begin
        (use-modules (guix build utils))
        (define %user
          (getpw #$(autossh-configuration-user config)))
        (let* ((directory #$(autossh-file-name config ""))
               (log (string-append directory "/log")))
          (mkdir-p directory)
          (chown directory (passwd:uid %user) (passwd:gid %user))
          (call-with-output-file log (const #t))
          (chown log (passwd:uid %user) (passwd:gid %user))))))

(define autossh-service-type
  (service-type
   (name 'autossh)
   (description "Automatically set up ssh connections (and keep them alive).")
   (extensions
    (list (service-extension shepherd-root-service-type
                             (compose list autossh-shepherd-service))
          (service-extension activation-service-type
                             autossh-service-activation)))
   (default-value (autossh-configuration))))

;;; ssh.scm ends here


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 Sou Bunnbu <iyzsong@member.fsf.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 services sysctl)
  #:use-module (gnu services)
  #:use-module (gnu services shepherd)
  #:use-module (gnu packages linux)
  #:use-module (guix gexp)
  #:use-module (guix records)
  #:use-module (srfi srfi-1)
  #:use-module (ice-9 match)
  #:export (sysctl-configuration
            sysctl-service-type))

;;;
;;; System Control Service.
;;;

(define-record-type* <sysctl-configuration>
  sysctl-configuration make-sysctl-configuration
  sysctl-configuration?
  (sysctl   sysctl-configuration-sysctl    ; path of the 'sysctl' command
            (default (file-append procps "/sbin/sysctl")))
  (settings sysctl-configuration-settings  ; alist of string pairs
            (default '())))

(define (sysctl-configuration-settings->sysctl.conf settings)
  "Return a file for @command{sysctl} to set kernel parameters as specified by
@var{settings}."
  (apply mixed-text-file "sysctl.conf"
         (append-map (match-lambda
                       ((key . value)
                        (list key "=" value "\n")))
                     settings)))

(define sysctl-shepherd-service
  (match-lambda
    (($ <sysctl-configuration> sysctl settings)
     (let ((sysctl.conf
            (sysctl-configuration-settings->sysctl.conf settings)))
       (shepherd-service
        (documentation "Configure kernel parameters at boot.")
        (provision '(sysctl))
        (start #~(lambda _
                   (zero? (system* #$sysctl "--load" #$sysctl.conf))))
        (one-shot? #t))))))

(define sysctl-service-type
  (service-type
   (name 'sysctl)
   (extensions
    (list (service-extension shepherd-root-service-type
                             (compose list sysctl-shepherd-service))))
   (compose concatenate)
   (extend (lambda (config settings)
             (sysctl-configuration
              (inherit config)
              (settings (append (sysctl-configuration-settings config)
                                settings)))))
   (default-value (sysctl-configuration))))

license: mit


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 nee  <nee-git@hidamari.blue>
;;;
;;; 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 services telephony)
  #:use-module (gnu services)
  #:use-module (gnu services shepherd)
  #:use-module (gnu system shadow)
  #:use-module (gnu packages admin)
  #:use-module (gnu packages telephony)
  #:use-module (guix records)
  #:use-module (guix gexp)
  #:use-module (srfi srfi-1)
  #:use-module (ice-9 match)
  #:export (murmur-configuration
            make-murmur-configuration
            murmur-configuration?
            murmur-configuration-package
            murmur-configuration-user
            murmur-configuration-group
            murmur-configuration-port
            murmur-configuration-welcome-text
            murmur-configuration-server-password
            murmur-configuration-max-users
            murmur-configuration-max-user-bandwidth
            murmur-configuration-database-file
            murmur-configuration-log-file
            murmur-configuration-pid-file
            murmur-configuration-autoban-attempts
            murmur-configuration-autoban-timeframe
            murmur-configuration-autoban-time
            murmur-configuration-opus-threshold
            murmur-configuration-channel-nesting-limit
            murmur-configuration-channelname-regex
            murmur-configuration-username-regex
            murmur-configuration-text-message-length
            murmur-configuration-image-message-length
            murmur-configuration-cert-required?
            murmur-configuration-remember-channel?
            murmur-configuration-allow-html?
            murmur-configuration-allow-ping?
            murmur-configuration-bonjour?
            murmur-configuration-send-version?
            murmur-configuration-log-days
            murmur-configuration-obfuscate-ips?
            murmur-configuration-ssl-cert
            murmur-configuration-ssl-key
            murmur-configuration-ssl-dh-params
            murmur-configuration-ssl-ciphers
            murmur-configuration-public-registration
            murmur-configuration-file

            murmur-public-registration-configuration
            make-murmur-public-registration-configuration
            murmur-public-registration-configuration?
            murmur-public-registration-configuration-name
            murmur-public-registration-configuration-url
            murmur-public-registration-configuration-password
            murmur-public-registration-configuration-hostname

            murmur-service-type))

;; https://github.com/mumble-voip/mumble/blob/master/scripts/murmur.ini

(define-record-type* <murmur-configuration> murmur-configuration
  make-murmur-configuration
  murmur-configuration?
  (package               murmur-configuration-package ;<package>
                         (default mumble))
  (user                  murmur-configuration-user
                         (default "murmur"))
  (group                 murmur-configuration-group
                         (default "murmur"))
  (port                  murmur-configuration-port
                         (default 64738))
  (welcome-text          murmur-configuration-welcome-text
                         (default ""))
  (server-password       murmur-configuration-server-password
                         (default ""))
  (max-users             murmur-configuration-max-users
                         (default 100))
  (max-user-bandwidth    murmur-configuration-max-user-bandwidth
                         (default #f))
  (database-file         murmur-configuration-database-file
                         (default "/var/lib/murmur/db.sqlite"))
  (log-file              murmur-configuration-log-file
                         (default "/var/log/murmur/murmur.log"))
  (pid-file              murmur-configuration-pid-file
                         (default "/var/run/murmur/murmur.pid"))
  (autoban-attempts      murmur-configuration-autoban-attempts
                         (default 10))
  (autoban-timeframe     murmur-configuration-autoban-timeframe
                         (default 120))
  (autoban-time          murmur-configuration-autoban-time
                         (default 300))
  (opus-threshold        murmur-configuration-opus-threshold
                         (default 100)) ; integer percent
  (channel-nesting-limit murmur-configuration-channel-nesting-limit
                         (default 10))
  (channelname-regex     murmur-configuration-channelname-regex
                         (default #f))
  (username-regex        murmur-configuration-username-regex
                         (default #f))
  (text-message-length   murmur-configuration-text-message-length
                         (default 5000))
  (image-message-length  murmur-configuration-image-message-length
                         (default (* 128 1024))) ; 128 Kilobytes
  (cert-required?         murmur-configuration-cert-required?
                          (default #f))
  (remember-channel?     murmur-configuration-remember-channel?
                         (default #f))
  (allow-html?           murmur-configuration-allow-html?
                         (default #f))
  (allow-ping?           murmur-configuration-allow-ping?
                         (default #f))
  (bonjour?              murmur-configuration-bonjour?
                         (default #f))
  (send-version?         murmur-configuration-send-version?
                         (default #f))
  (log-days              murmur-configuration-log-days
                         (default 31))
  (obfuscate-ips?        murmur-obfuscate-ips?
                         (default #t))
  (ssl-cert              murmur-configuration-ssl-cert
                         (default #f))
  (ssl-key               murmur-configuration-ssl-key
                         (default #f))
  (ssl-dh-params         murmur-configuration-ssl-dh-params
                         (default #f))
  (ssl-ciphers           murmur-configuration-ssl-ciphers
                         (default #f))
  (public-registration   murmur-configuration-public-registration
                         (default #f))  ; <murmur-public-registration-configuration>
  (file                  murmur-configuration-file
                         (default #f)))

(define-record-type* <murmur-public-registration-configuration>
  murmur-public-registration-configuration
  make-murmur-public-registration-configuration
  murmur-public-registration-configuration?
  (name         murmur-public-registration-configuration-name)
  (password     murmur-public-registration-configuration-password)
  (url          murmur-public-registration-configuration-url)
  (hostname     murmur-public-registration-configuration-hostname
                (default #f)))

(define (flatten . lst)
  "Return a list that recursively concatenates all sub-lists of LST."
  (define (flatten1 head out)
    (if (list? head)
        (fold-right flatten1 out head)
        (cons head out)))
  (fold-right flatten1 '() lst))

(define (default-murmur-config config)
  (match-record
   config
   <murmur-configuration>
   (user port welcome-text server-password max-users max-user-bandwidth
    database-file log-file pid-file autoban-attempts autoban-timeframe
    autoban-time opus-threshold channel-nesting-limit channelname-regex
    username-regex text-message-length image-message-length cert-required?
    remember-channel? allow-html? allow-ping? bonjour? send-version?
    log-days obfuscate-ips? ssl-cert ssl-key ssl-dh-params ssl-ciphers
    public-registration)
   (apply mixed-text-file "murmur.ini"
          (flatten
           "welcometext=" welcome-text "\n"
           "port=" (number->string port) "\n"
           (if server-password (list "serverpassword=" server-password "\n") '())
           (if max-user-bandwidth (list "bandwidth="
                                        (number->string max-user-bandwidth) "\n")
               '())
           "users=" (number->string max-users) "\n"
           "uname=" user "\n"
           "database=" database-file "\n"
           "logfile=" log-file "\n"
           "pidfile=" pid-file "\n"
           (if autoban-attempts (list "autobanAttempts=" (number->string autoban-attempts) "\n") '())
           (if autoban-timeframe (list "autobanTimeframe=" (number->string autoban-timeframe) "\n") '())
           (if autoban-time (list "autobanTime=" (number->string autoban-time) "\n") '())
           (if opus-threshold (list "opusthreshold=" (number->string opus-threshold) "\n") '())
           (if channel-nesting-limit (list "channelnestinglimit=" (number->string channel-nesting-limit) "\n") '())
           (if channelname-regex (list "channelname=" channelname-regex "\n") '())
           (if username-regex (list "username=" username-regex "\n") '())
           (if text-message-length (list "textmessagelength=" (number->string text-message-length) "\n") '())
           (if image-message-length (list "imagemessagelength=" (number->string image-message-length) "\n") '())
           (if log-days (list "logdays=" (number->string log-days) "\n") '())
           "obfuscate=" (if obfuscate-ips? "true" "false") "\n"
           "certrequired=" (if cert-required? "true" "false") "\n"
           "rememberchannel=" (if remember-channel? "true" "false") "\n"
           "allowhtml=" (if allow-html? "true" "false") "\n"
           "allowping=" (if allow-ping? "true" "false") "\n"
           "bonjour=" (if bonjour? "true" "false") "\n"
           "sendversion=" (if send-version? "true" "false") "\n"
           (cond ((and ssl-cert ssl-key)
                  (list
                   "sslCert=" ssl-cert "\n"
                   "sslKey=" ssl-key "\n"))
                 ((or ssl-cert ssl-key)
                  (error "ssl-cert and ssl-key must both be set"
                         ssl-cert ssl-key))
                 (else '()))
           (if ssl-dh-params (list "sslDHParams=" ssl-dh-params) '())
           (if ssl-ciphers (list "sslCiphers=" ssl-ciphers) '())

           (match public-registration
             (#f '())
             (($ <murmur-public-registration-configuration>
                 name password url hostname)
              (if (and (or (not server-password) (string-null? server-password))
                       allow-ping?)
                  (list
                   "registerName=" name "\n"
                   "registerPassword=" password "\n"
                   "registerUrl=" url "\n"
                   (if hostname
                       (string-append "registerHostname=" hostname "\n")
                       ""))
                  (error "To publicly register your murmur server your server must be publicy visible
and users must be able to join without a password. To fix this set:
(allow-ping? #t)
(server-password \"\")
Or set public-registration to #f"))))))))

(define (murmur-activation config)
  #~(begin
      (use-modules (guix build utils))
      (let* ((log-dir (dirname #$(murmur-configuration-log-file config)))
             (pid-dir (dirname #$(murmur-configuration-pid-file config)))
             (db-dir (dirname #$(murmur-configuration-database-file config)))
             (user (getpwnam #$(murmur-configuration-user config)))
             (init-dir
              (lambda (name dir)
                (format #t "creating murmur ~a directory '~a'\n" name dir)
                (mkdir-p dir)
                (chown dir (passwd:uid user) (passwd:gid user))
                (chmod dir #o700)))
             (ini #$(or (murmur-configuration-file config)
                        (default-murmur-config config))))
        (init-dir "log" log-dir)
        (init-dir "pid" pid-dir)
        (init-dir "database" db-dir)

        (format #t "murmur: use config file: ~a~%\n" ini)
        (format #t "murmur: to set the SuperUser password run:
    `~a -ini ~a -readsupw`\n"
                #$(file-append (murmur-configuration-package config)
                               "/bin/murmurd") ini)
        #t)))

(define murmur-accounts
  (match-lambda
    (($ <murmur-configuration> _ user group)
     (list
      (user-group
       (name group)
       (system? #t))
      (user-account
       (name user)
       (group group)
       (system? #t)
       (comment "Murmur Daemon")
       (home-directory "/var/empty")
       (shell (file-append shadow "/sbin/nologin")))))))

(define (murmur-shepherd-service config)
  (list (shepherd-service
         (provision '(murmur))
         (documentation "Run the Murmur Mumble server.")
         (requirement '(networking))
         (start #~(make-forkexec-constructor
                   '(#$(file-append (murmur-configuration-package config)
                                    "/bin/murmurd")
                     "-ini"
                     #$(or (murmur-configuration-file config)
                           (default-murmur-config config)))
                   #:pid-file #$(murmur-configuration-pid-file config)))
         (stop #~(make-kill-destructor)))))

(define murmur-service-type
  (service-type (name 'murmur)
                (description
                 "Run the Murmur voice-over-IP (VoIP) server of the Mumble
suite.")
                (extensions
                 (list (service-extension shepherd-root-service-type
                                          murmur-shepherd-service)
                       (service-extension activation-service-type
                                          murmur-activation)
                       (service-extension account-service-type
                                          murmur-accounts)))
                (default-value (murmur-configuration))))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016 Nikita <nikita@n0.is>
;;; Copyright © 2016 Sou Bunnbu <iyzsong@member.fsf.org>
;;; Copyright © 2017 Oleg Pykhalov <go.wigust@gmail.com>
;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
;;; Copyright © 2018 Christopher Baines <mail@cbaines.net>
;;;
;;; 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 services version-control)
  #:use-module (gnu services)
  #:use-module (gnu services base)
  #:use-module (gnu services shepherd)
  #:use-module (gnu services web)
  #:use-module (gnu system shadow)
  #:use-module (gnu packages version-control)
  #:use-module (gnu packages admin)
  #:use-module (guix records)
  #:use-module (guix gexp)
  #:use-module (guix store)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 format)
  #:use-module (ice-9 match)
  #:export (git-daemon-service
            git-daemon-service-type
            git-daemon-configuration
            git-daemon-configuration?

            git-http-configuration
            git-http-configuration?
            git-http-nginx-location-configuration

            <gitolite-configuration>
            gitolite-configuration
            gitolite-configuration-package
            gitolite-configuration-user
            gitolite-configuration-rc-file
            gitolite-configuration-admin-pubkey

            <gitolite-rc-file>
            gitolite-rc-file
            gitolite-rc-file-umask
            gitolite-rc-file-git-config-keys
            gitolite-rc-file-roles
            gitolite-rc-file-enable

            gitolite-service-type))

;;; Commentary:
;;;
;;; Version Control related services.
;;;
;;; Code:

;;;
;;; Git daemon.
;;;

(define-record-type* <git-daemon-configuration>
  git-daemon-configuration
  make-git-daemon-configuration
  git-daemon-configuration?
  (package          git-daemon-configuration-package        ;package
                    (default git))
  (export-all?      git-daemon-configuration-export-all     ;boolean
                    (default #f))
  (base-path        git-daemon-configuration-base-path      ;string | #f
                    (default "/srv/git"))
  (user-path        git-daemon-configuration-user-path      ;string | #f
                    (default #f))
  (listen           git-daemon-configuration-listen         ;list of string
                    (default '()))
  (port             git-daemon-configuration-port           ;number | #f
                    (default #f))
  (whitelist        git-daemon-configuration-whitelist      ;list of string
                    (default '()))
  (extra-options    git-daemon-configuration-extra-options  ;list of string
                    (default '())))

(define git-daemon-shepherd-service
  (match-lambda
    (($ <git-daemon-configuration>
        package export-all? base-path user-path
        listen port whitelist extra-options)
     (let* ((git     (file-append package "/bin/git"))
            (command `(,git
                       "daemon" "--syslog" "--reuseaddr"
                       ,@(if export-all?
                             '("--export-all")
                             '())
                       ,@(if base-path
                             `(,(string-append "--base-path=" base-path))
                             '())
                       ,@(if user-path
                             `(,(string-append "--user-path=" user-path))
                             '())
                       ,@(map (cut string-append "--listen=" <>) listen)
                       ,@(if port
                             `(,(string-append
                                 "--port=" (number->string port)))
                             '())
                       ,@extra-options
                       ,@whitelist)))
       (list (shepherd-service
              (documentation "Run the git-daemon.")
              (requirement '(networking))
              (provision '(git-daemon))
              (start #~(make-forkexec-constructor '#$command
                                                  #:user "git-daemon"
                                                  #:group "git-daemon"))
              (stop #~(make-kill-destructor))))))))

(define %git-daemon-accounts
  ;; User account and group for git-daemon.
  (list (user-group
         (name "git-daemon")
         (system? #t))
        (user-account
         (name "git-daemon")
         (system? #t)
         (group "git-daemon")
         (comment "Git daemon user")
         (home-directory "/var/empty")
         (shell (file-append shadow "/sbin/nologin")))))

(define (git-daemon-activation config)
  "Return the activation gexp for git-daemon using CONFIG."
  (let ((base-path (git-daemon-configuration-base-path config)))
    #~(begin
        (use-modules (guix build utils))
        ;; Create the 'base-path' directory when it's not '#f'.
        (and=> #$base-path mkdir-p))))

(define git-daemon-service-type
  (service-type
   (name 'git-daemon)
   (extensions
    (list (service-extension shepherd-root-service-type
                             git-daemon-shepherd-service)
          (service-extension account-service-type
                             (const %git-daemon-accounts))
          (service-extension activation-service-type
                             git-daemon-activation)))
   (description
    "Expose Git repositories over the insecure @code{git://} TCP-based
protocol.")
   (default-value (git-daemon-configuration))))

(define* (git-daemon-service #:key (config (git-daemon-configuration)))
  "Return a service that runs @command{git daemon}, a simple TCP server to
expose repositories over the Git protocol for annoymous access.

The optional @var{config} argument should be a
@code{<git-daemon-configuration>} object, by default it allows read-only
access to exported repositories under @file{/srv/git}."
  (service git-daemon-service-type config))

;;;
;;; HTTP access.  Add the result of calling
;;; git-http-nginx-location-configuration to an nginx-server-configuration's
;;; "locations" field.
;;;

(define-record-type* <git-http-configuration>
  git-http-configuration
  make-git-http-configuration
  git-http-configuration?
  (package          git-http-configuration-package        ;package
                    (default git))
  (git-root         git-http-configuration-git-root       ;string
                    (default "/srv/git"))
  (export-all?      git-http-configuration-export-all?    ;boolean
                    (default #f))
  (uri-path         git-http-configuration-uri-path       ;string
                    (default "/git/"))
  (fcgiwrap-socket  git-http-configuration-fcgiwrap-socket ;string
                    (default "127.0.0.1:9000")))

(define* (git-http-nginx-location-configuration #:optional
                                                (config
                                                 (git-http-configuration)))
  (match config
    (($ <git-http-configuration> package git-root export-all?
                                 uri-path fcgiwrap-socket)
     (nginx-location-configuration
      (uri (string-append "~ /" (string-trim-both uri-path #\/) "(/.*)"))
      (body
       (list
        (list "fastcgi_pass " fcgiwrap-socket ";")
        (list "fastcgi_param SCRIPT_FILENAME "
              package "/libexec/git-core/git-http-backend"
              ";")
        "fastcgi_param QUERY_STRING $query_string;"
        "fastcgi_param REQUEST_METHOD $request_method;"
        "fastcgi_param CONTENT_TYPE $content_type;"
        "fastcgi_param CONTENT_LENGTH $content_length;"
        (if export-all?
            "fastcgi_param GIT_HTTP_EXPORT_ALL \"\";"
            "")
        (list "fastcgi_param GIT_PROJECT_ROOT " git-root ";")
        "fastcgi_param PATH_INFO $1;"))))))

;;;
;;; Gitolite
;;;

(define-record-type* <gitolite-rc-file>
  gitolite-rc-file make-gitolite-rc-file
  gitolite-rc-file?
  (umask           gitolite-rc-file-umask
                   (default #o0077))
  (git-config-keys gitolite-rc-file-git-config-keys
                   (default ""))
  (roles           gitolite-rc-file-roles
                   (default '(("READERS" . 1)
                              ("WRITERS" . 1))))
  (enable          gitolite-rc-file-enable
                   (default '("help"
                              "desc"
                              "info"
                              "perms"
                              "writable"
                              "ssh-authkeys"
                              "git-config"
                              "daemon"
                              "gitweb"))))

(define-gexp-compiler (gitolite-rc-file-compiler
                       (file <gitolite-rc-file>) system target)
  (match file
    (($ <gitolite-rc-file> umask git-config-keys roles enable)
     (apply text-file* "gitolite.rc"
      `("%RC = (\n"
        "    UMASK => " ,(format #f "~4,'0o" umask) ",\n"
        "    GIT_CONFIG_KEYS => '" ,git-config-keys "',\n"
        "    ROLES => {\n"
        ,@(map (match-lambda
                 ((role . value)
                  (simple-format #f "        ~A => ~A,\n" role value)))
               roles)
        "    },\n"
        "\n"
        "    ENABLE => [\n"
        ,@(map (lambda (value)
                 (simple-format #f "        '~A',\n" value))
               enable)
        "    ],\n"
        ");\n"
        "\n"
        "1;\n")))))

(define-record-type* <gitolite-configuration>
  gitolite-configuration make-gitolite-configuration
  gitolite-configuration?
  (package        gitolite-configuration-package
                  (default gitolite))
  (user           gitolite-configuration-user
                  (default "git"))
  (group          gitolite-configuration-group
                  (default "git"))
  (home-directory gitolite-configuration-home-directory
                  (default "/var/lib/gitolite"))
  (rc-file        gitolite-configuration-rc-file
                  (default (gitolite-rc-file)))
  (admin-pubkey   gitolite-configuration-admin-pubkey))

(define gitolite-accounts
  (match-lambda
    (($ <gitolite-configuration> package user group home-directory
                                 rc-file admin-pubkey)
     ;; User group and account to run Gitolite.
     (list (user-group (name user) (system? #t))
           (user-account
            (name user)
            (group group)
            (system? #t)
            (comment "Gitolite user")
            (home-directory home-directory))))))

(define gitolite-activation
  (match-lambda
    (($ <gitolite-configuration> package user group home
                                 rc-file admin-pubkey)
     #~(begin
         (use-modules (ice-9 match)
                      (guix build utils))

         (let* ((user-info (getpwnam #$user))
                (admin-pubkey #$admin-pubkey)
                (pubkey-file (string-append
                              #$home "/"
                              (basename
                               (strip-store-file-name admin-pubkey)))))

           (simple-format #t "guix: gitolite: installing ~A\n" #$rc-file)
           (copy-file #$rc-file #$(string-append home "/.gitolite.rc"))

           ;; The key must be writable, so copy it from the store
           (copy-file admin-pubkey pubkey-file)

           (chmod pubkey-file #o500)
           (chown pubkey-file
                  (passwd:uid user-info)
                  (passwd:gid user-info))

           ;; Set the git configuration, to avoid gitolite trying to use
           ;; the hostname command, as the network might not be up yet
           (with-output-to-file #$(string-append home "/.gitconfig")
             (lambda ()
               (display "[user]
        name = GNU Guix
        email = guix@localhost
")))
           ;; Run Gitolite setup, as this updates the hooks and include the
           ;; admin pubkey if specified. The admin pubkey is required for
           ;; initial setup, and will replace the previous key if run after
           ;; initial setup
           (match (primitive-fork)
             (0
              ;; Exit with a non-zero status code if an exception is thrown.
              (dynamic-wind
                (const #t)
                (lambda ()
                  (setenv "HOME" (passwd:dir user-info))
                  (setenv "USER" #$user)
                  (setgid (passwd:gid user-info))
                  (setuid (passwd:uid user-info))
                  (primitive-exit
                   (system* #$(file-append package "/bin/gitolite")
                            "setup"
                            "-m" "gitolite setup by GNU Guix"
                            "-pk" pubkey-file)))
                (lambda ()
                  (primitive-exit 1))))
             (pid (waitpid pid)))

           (when (file-exists? pubkey-file)
             (delete-file pubkey-file)))))))

(define gitolite-service-type
  (service-type
   (name 'gitolite)
   (extensions
    (list (service-extension activation-service-type
                             gitolite-activation)
          (service-extension account-service-type
                             gitolite-accounts)
          (service-extension profile-service-type
                             ;; The Gitolite package in Guix uses
                             ;; gitolite-shell in the authorized_keys file, so
                             ;; gitolite-shell needs to be on the PATH for
                             ;; gitolite to work.
                             (lambda (config)
                               (list
                                (gitolite-configuration-package config))))))
   (description
    "Setup @command{gitolite}, a Git hosting tool providing access over SSH..
By default, the @code{git} user is used, but this is configurable.
Additionally, Gitolite can integrate with with tools like gitweb or cgit to
provide a web interface to view selected repositories.")))


code:
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 Ryan Moe <ryan.moe@gmail.com>
;;; Copyright © 2018, 2020 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <janneke@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 services virtualization)
  #:use-module (gnu bootloader)
  #:use-module (gnu bootloader grub)
  #:use-module (gnu image)
  #:use-module (gnu packages admin)
  #:use-module (gnu packages ssh)
  #:use-module (gnu packages virtualization)
  #:use-module (gnu services base)
  #:use-module (gnu services configuration)
  #:use-module (gnu services dbus)
  #:use-module (gnu services shepherd)
  #:use-module (gnu services ssh)
  #:use-module (gnu services)
  #:use-module (gnu system file-systems)
  #:use-module (gnu system hurd)
  #:use-module (gnu system image)
  #:use-module (gnu system images hurd)
  #:use-module (gnu system shadow)
  #:use-module (gnu system)
  #:use-module (guix derivations)
  #:use-module (guix gexp)
  #:use-module (guix modules)
  #:use-module (guix monads)
  #:use-module (guix packages)
  #:use-module (guix records)
  #:use-module (guix store)
  #:use-module (guix utils)

  #:use-module (srfi srfi-9)
  #:use-module (srfi srfi-26)
  #:use-module (rnrs bytevectors)
  #:use-module (ice-9 match)

  #:export (%hurd-vm-operating-system
            hurd-vm-configuration
            hurd-vm-configuration?
            hurd-vm-configuration-os
            hurd-vm-configuration-qemu
            hurd-vm-configuration-image
            hurd-vm-configuration-disk-size
            hurd-vm-configuration-memory-size
            hurd-vm-configuration-options
            hurd-vm-configuration-id
            hurd-vm-configuration-net-options
            hurd-vm-configuration-secrets

            hurd-vm-disk-image
            hurd-vm-port
            hurd-vm-net-options
            hurd-vm-service-type

            libvirt-configuration
            libvirt-service-type
            virtlog-configuration
            virtlog-service-type

            %qemu-platforms
            lookup-qemu-platforms
            qemu-platform?
            qemu-platform-name

            qemu-binfmt-configuration
            qemu-binfmt-configuration?
            qemu-binfmt-service-type))

(define (uglify-field-name field-name)
  (let ((str (symbol->string field-name)))
    (string-join
     (string-split (string-delete #\? str) #\-)
     "_")))

(define (quote-val val)
  (string-append "\"" val "\""))

(define (serialize-field field-name val)
  (format #t "~a = ~a\n" (uglify-field-name field-name) val))

(define (serialize-string field-name val)
  (serialize-field field-name (quote-val val)))

(define (serialize-boolean field-name val)
  (serialize-field field-name (if val 1 0)))

(define (serialize-integer field-name val)
  (serialize-field field-name val))

(define (build-opt-list val)
  (string-append
   "["
   (string-join (map quote-val val) ",")
   "]"))

(define optional-list? list?)
(define optional-string? string?)

(define (serialize-list field-name val)
  (serialize-field field-name (build-opt-list val)))

(define (serialize-optional-list field-name val)
  (if (null? val)
      (format #t "# ~a = []\n" (uglify-field-name field-name))
      (serialize-list field-name val)))

(define (serialize-optional-string field-name val)
  (if (string-null? val)
      (format #t "# ~a = \"\"\n" (uglify-field-name field-name))
      (serialize-string field-name val)))

(define-configuration libvirt-configuration
  (libvirt
   (package libvirt)
   "Libvirt package.")
  (listen-tls?
   (boolean #t)
   "Flag listening for secure TLS connections on the public TCP/IP port.
must set @code{listen} for this to have any effect.

It is necessary to setup a CA and issue server certificates before
using this capability.")
  (listen-tcp?
   (boolean #f)
   "Listen for unencrypted TCP connections on the public TCP/IP port.
must set @code{listen} for this to have any effect.

Using the TCP socket requires SASL authentication by default. Only
SASL mechanisms which support data encryption are allowed. This is
DIGEST_MD5 and GSSAPI (Kerberos5)")
  (tls-port
   (string "16514")
   "Port for accepting secure TLS connections This can be a port number,
or service name")
  (tcp-port
   (string "16509")
   "Port for accepting insecure TCP connections This can be a port number,
or service name")
  (listen-addr
   (string "0.0.0.0")
   "IP address or hostname used for client connections.")
  (mdns-adv?
   (boolean #f)
   "Flag toggling mDNS advertisement of the libvirt service.

Alternatively can disable for all services on a host by
stopping the Avahi daemon.")
  (mdns-name
   (string (string-append "Virtualization Host " (gethostname)))
   "Default mDNS advertisement name. This must be unique on the
immediate broadcast network.")
  (unix-sock-group
   (string "root")
   "UNIX domain socket group ownership. This can be used to
allow a 'trusted' set of users access to management capabilities
without becoming root.")
  (unix-sock-ro-perms
   (string "0777")
   "UNIX socket permissions for the R/O socket. This is used
for monitoring VM status only.")
  (unix-sock-rw-perms
   (string "0770")
   "UNIX socket permissions for the R/W socket. Default allows
only root. If PolicyKit is enabled on the socket, the default
will change to allow everyone (eg, 0777)")
  (unix-sock-admin-perms
   (string "0777")
   "UNIX socket permissions for the admin socket. Default allows
only owner (root), do not change it unless you are sure to whom
you are exposing the access to.")
  (unix-sock-dir
   (string "/var/run/libvirt")
   "The directory in which sockets will be found/created.")
  (auth-unix-ro
   (string "polkit")
   "Authentication scheme for UNIX read-only sockets. By default
socket permissions allow anyone to connect")
  (auth-unix-rw
   (string "polkit")
   "Authentication scheme for UNIX read-write sockets. By default
socket permissions only allow root. If PolicyKit support was compiled
into libvirt, the default will be to use 'polkit' auth.")
  (auth-tcp
   (string "sasl")
   "Authentication scheme for TCP sockets. If you don't enable SASL,
then all TCP traffic is cleartext. Don't do this outside of a dev/test
scenario.")
  (auth-tls
   (string "none")
   "Authentication scheme for TLS sockets. TLS sockets already have
encryption provided by the TLS layer, and limited authentication is
done by certificates.

It is possible to make use of any SASL authentication mechanism as
well, by using 'sasl' for this option")
  (access-drivers
   (optional-list '())
   "API access control scheme.

By default an authenticated user is allowed access to all APIs. Access
drivers can place restrictions on this.")
  (key-file
   (string "")
   "Server key file path. If set to an empty string, then no private key
is loaded.")
  (cert-file
   (string "")
   "Server key file path. If set to an empty string, then no certificate
is loaded.")
  (ca-file
   (string "")
   "Server key file path. If set to an empty string, then no CA certificate
is loaded.")
  (crl-file
   (string "")
   "Certificate revocation list path. If set to an empty string, then no
CRL is loaded.")
  (tls-no-sanity-cert
   (boolean #f)
   "Disable verification of our own server certificates.

When libvirtd starts it performs some sanity checks against its own
certificates.")
  (tls-no-verify-cert
   (boolean #f)
   "Disable verification of client certificates.

Client certificate verification is the primary authentication mechanism.
Any client which does not present a certificate signed by the CA
will be rejected.")
  (tls-allowed-dn-list
   (optional-list '())
   "Whitelist of allowed x509 Distinguished Name.")
  (sasl-allowed-usernames
   (optional-list '())
   "Whitelist of allowed SASL usernames. The format for username
depends on the SASL authentication mechanism.")
  (tls-priority
   (string "NORMAL")
   "Override the compile time default TLS priority string. The
default is usually \"NORMAL\" unless overridden at build time.
Only set this is it is desired for libvirt to deviate from
the global default settings.")
  (max-clients
   (integer 5000)
   "Maximum number of concurrent client connections to allow
over all sockets combined.")
  (max-queued-clients
   (integer 1000)
   "Maximum length of queue of connections waiting to be
accepted by the daemon. Note, that some protocols supporting
retransmission may obey this so that a later reattempt at
connection succeeds.")
  (max-anonymous-clients
   (integer 20)
   "Maximum length of queue of accepted but not yet authenticated
clients. Set this to zero to turn this feature off")
  (min-workers
   (integer 5)
   "Number of workers to start up initially.")
  (max-workers
   (integer 20)
   "Maximum number of worker threads.

If the number of active clients exceeds @code{min-workers},
then more threads are spawned, up to max_workers limit.
Typically you'd want max_workers to equal maximum number
of clients allowed.")
  (prio-workers
   (integer 5)
   "Number of priority workers. If all workers from above
pool are stuck, some calls marked as high priority
(notably domainDestroy) can be executed in this pool.")
  (max-requests
    (integer 20)
    "Total global limit on concurrent RPC calls.")
  (max-client-requests
    (integer 5)
    "Limit on concurrent requests from a single client
connection. To avoid one client monopolizing the server
this should be a small fraction of the global max_requests
and max_workers parameter.")
  (admin-min-workers
    (integer 1)
    "Same as @code{min-workers} but for the admin interface.")
  (admin-max-workers
     (integer 5)
    "Same as @code{max-workers} but for the admin interface.")
  (admin-max-clients
    (integer 5)
    "Same as @code{max-clients} but for the admin interface.")
  (admin-max-queued-clients
    (integer 5)
    "Same as @code{max-queued-clients} but for the admin interface.")
  (admin-max-client-requests
    (integer 5)
    "Same as @code{max-client-requests} but for the admin interface.")
  (log-level
    (integer 3)
    "Logging level. 4 errors, 3 warnings, 2 information, 1 debug.")
  (log-filters
    (string "3:remote 4:event")
    "Logging filters.

A filter allows selecting a different logging level for a given category
of logs
The format for a filter is one of:
@itemize
@item x:name

@item x:+name
@end itemize

where @code{name} is a string which is matched against the category
given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
file, e.g., \"remote\", \"qemu\", or \"util.json\" (the name in the
filter can be a substring of the full category name, in order
to match multiple similar categories), the optional \"+\" prefix
tells libvirt to log stack trace for each message matching
name, and @code{x} is the minimal level where matching messages should
be logged:

@itemize
@item 1: DEBUG
@item 2: INFO
@item 3: WARNING
@item 4: ERROR
@end itemize

Multiple filters can be defined in a single filters statement, they just
need to be separated by spaces.")
  (log-outputs
    (string "3:syslog:libvirtd")
    "Logging outputs.

An output is one of the places to save logging information
The format for an output can be:

@table @code
@item x:stderr
output goes to stderr

@item x:syslog:name
use syslog for the output and use the given name as the ident

@item x:file:file_path
output to a file, with the given filepath

@item x:journald
output to journald logging system
@end table

In all case the x prefix is the minimal level, acting as a filter

@itemize
@item 1: DEBUG
@item 2: INFO
@item 3: WARNING
@item 4: ERROR
@end itemize

Multiple outputs can be defined, they just need to be separated by spaces.")
  (audit-level
    (integer 1)
    "Allows usage of the auditing subsystem to be altered

@itemize
@item 0: disable all auditing
@item 1: enable auditing, only if enabled on host
@item 2: enable auditing, and exit if disabled on host.
@end itemize
")
  (audit-logging
    (boolean #f)
    "Send audit messages via libvirt logging infrastructure.")
  (host-uuid
    (optional-string "")
    "Host UUID. UUID must not have all digits be the same.")
  (host-uuid-source
    (string "smbios")
    "Source to read host UUID.

@itemize

@item @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}

@item @code{machine-id}: fetch the UUID from @code{/etc/machine-id}

@end itemize

If @code{dmidecode} does not provide a valid UUID a temporary UUID
will be generated.")
  (keepalive-interval
    (integer 5)
    "A keepalive message is sent to a client after
@code{keepalive_interval} seconds of inactivity to check if
the client is still responding. If set to -1, libvirtd will
never send keepalive requests; however clients can still send
them and the daemon will send responses.")
  (keepalive-count
    (integer 5)
    "Maximum number of keepalive messages that are allowed to be sent
to the client without getting any response before the connection is
considered broken.

In other words, the connection is automatically
closed approximately after
@code{keepalive_interval * (keepalive_count + 1)} seconds since the last
message received from the client. When @code{keepalive-count} is
set to 0, connections will be automatically closed after
@code{keepalive-interval} seconds of inactivity without sending any
keepalive messages.")
  (admin-keepalive-interval
    (integer 5)
    "Same as above but for admin interface.")
  (admin-keepalive-count
    (integer 5)
    "Same as above but for admin interface.")
  (ovs-timeout
    (integer 5)
    "Timeout for Open vSwitch calls.

The @code{ovs-vsctl} utility is used for the configuration and
its timeout option is set by default to 5 seconds to avoid
potential infinite waits blocking libvirt."))

(define* (libvirt-conf-file config)
  "Return a libvirtd config file."
  (plain-file "libvirtd.conf"
              (with-output-to-string
                (lambda ()
                  (serialize-configuration config libvirt-configuration-fields)))))

(define %libvirt-accounts
  (list (user-group (name "libvirt") (system? #t))))

(define (%libvirt-activation config)
  (let ((sock-dir (libvirt-configuration-unix-sock-dir config)))
    #~(begin
        (use-modules (guix build utils))
        (mkdir-p #$sock-dir))))

(define (libvirt-shepherd-service config)
  (let* ((config-file (libvirt-conf-file config))
         (libvirt (libvirt-configuration-libvirt config)))
    (list (shepherd-service
           (documentation "Run the libvirt daemon.")
           (provision '(libvirtd))
           (start #~(make-forkexec-constructor
                     (list (string-append #$libvirt "/sbin/libvirtd")
                           "-f" #$config-file)
                     ;; For finding qemu and ip binaries.
                     #:environment-variables
                     (list (string-append
                            "PATH=/run/current-system/profile/bin:"
                            "/run/current-system/profile/sbin"))))
           (stop #~(make-kill-destructor))))))

(define libvirt-service-type
  (service-type (name 'libvirt)
		(extensions
                 (list
                  (service-extension polkit-service-type
                                     (compose list libvirt-configuration-libvirt))
                  (service-extension profile-service-type
                                     (lambda (config)
                                       (list
                                        (libvirt-configuration-libvirt config)
                                        qemu)))
                  (service-extension activation-service-type
                                     %libvirt-activation)
                  (service-extension shepherd-root-service-type
                                     libvirt-shepherd-service)
                  (service-extension account-service-type
                                     (const %libvirt-accounts))))
                (default-value (libvirt-configuration))))

(define-record-type* <virtlog-configuration>
  virtlog-configuration make-virtlog-configuration
  virtlog-configuration?
  (libvirt      virtlog-configuration-libvirt
                (default libvirt))
  (log-level    virtlog-configuration-log-level
                (default 3))
  (log-filters  virtlog-configuration-log-filters
                (default "3:remote 4:event"))
  (log-outputs  virtlog-configuration-log-outputs
                (default "3:syslog:virtlogd"))
  (max-clients  virtlog-configuration-max-clients
                (default 1024))
  (max-size     virtlog-configuration-max-size
                (default 2097152)) ;; 2MB
  (max-backups  virtlog-configuration-max-backups
                (default 3)))

(define* (virtlogd-conf-file config)
  "Return a virtlogd config file."
  (plain-file "virtlogd.conf"
              (string-append
               "log_level = " (number->string (virtlog-configuration-log-level config)) "\n"
               "log_filters = \"" (virtlog-configuration-log-filters config) "\"\n"
               "log_outputs = \"" (virtlog-configuration-log-outputs config) "\"\n"
               "max_clients = " (number->string (virtlog-configuration-max-clients config)) "\n"
               "max_size = " (number->string (virtlog-configuration-max-size config)) "\n"
               "max_backups = " (number->string (virtlog-configuration-max-backups config)) "\n")))

(define (virtlogd-shepherd-service config)
  (let* ((config-file (virtlogd-conf-file config))
         (libvirt (virtlog-configuration-libvirt config)))
    (list (shepherd-service
           (documentation "Run the virtlog daemon.")
           (provision '(virtlogd))
           (start #~(make-forkexec-constructor
                     (list (string-append #$libvirt "/sbin/virtlogd")
                           "-f" #$config-file)))
           (stop #~(make-kill-destructor))))))

(define virtlog-service-type
  (service-type (name 'virtlogd)
		(extensions
                 (list
                  (service-extension shepherd-root-service-type
                                     virtlogd-shepherd-service)))
                (default-value (virtlog-configuration))))

(define (generate-libvirt-documentation)
  (generate-documentation
   `((libvirt-configuration ,libvirt-configuration-fields))
   'libvirt-configuration))

;;;
;;; Transparent QEMU emulation via binfmt_misc.
;;;

;; Platforms that QEMU can emulate.
(define-record-type <qemu-platform>
  (qemu-platform name family magic mask)
  qemu-platform?
  (name     qemu-platform-name)                   ;string
  (family   qemu-platform-family)                 ;string
  (magic    qemu-platform-magic)                  ;bytevector
  (mask     qemu-platform-mask))                  ;bytevector

(define-syntax bv
  (lambda (s)
    "Expand the given string into a bytevector."
    (syntax-case s ()
      ((_ str)
       (string? (syntax->datum #'str))
       (let ((bv (u8-list->bytevector
                  (map char->integer
                       (string->list (syntax->datum #'str))))))
         bv)))))

;;; The platform descriptions below are taken from
;;; 'scripts/qemu-binfmt-conf.sh' in QEMU.

(define %i386
  (qemu-platform "i386" "i386"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x03\x00")
                 (bv "\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %i486
  (qemu-platform "i486" "i386"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x06\x00")
                 (bv "\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %alpha
  (qemu-platform "alpha" "alpha"
                 (bv "\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x26\x90")
                 (bv "\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %arm
  (qemu-platform "arm" "arm"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %armeb
  (qemu-platform "armeb" "arm"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %sparc
  (qemu-platform "sparc" "sparc"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x02")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %sparc32plus
  (qemu-platform "sparc32plus" "sparc"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x12")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %ppc
  (qemu-platform "ppc" "ppc"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x14")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %ppc64
  (qemu-platform "ppc64" "ppc"
                 (bv "\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x15")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %ppc64le
  (qemu-platform "ppc64le" "ppcle"
                 (bv "\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x15\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\x00")))

(define %m68k
  (qemu-platform "m68k" "m68k"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x04")
                 (bv "\xff\xff\xff\xff\xff\xff\xfe\xfe\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

;; XXX: We could use the other endianness on a MIPS host.
(define %mips
  (qemu-platform "mips" "mips"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %mipsel
  (qemu-platform "mipsel" "mips"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %mipsn32
  (qemu-platform "mipsn32" "mips"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %mipsn32el
  (qemu-platform "mipsn32el" "mips"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %mips64
  (qemu-platform "mips64" "mips"
                 (bv "\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %mips64el
  (qemu-platform "mips64el" "mips"
                 (bv "\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x08\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %riscv32
  (qemu-platform "riscv32" "riscv"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xf3\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %riscv64
  (qemu-platform "riscv64" "riscv"
                 (bv "\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xf3\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %sh4
  (qemu-platform "sh4" "sh4"
                 (bv "\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %sh4eb
  (qemu-platform "sh4eb" "sh4"
                 (bv "\x7fELF\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x2a")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %s390x
  (qemu-platform "s390x" "s390x"
                 (bv "\x7fELF\x02\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x16")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %aarch64
  (qemu-platform "aarch64" "arm"
                 (bv "\x7fELF\x02\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\xb7\x00")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff")))

(define %hppa
  (qemu-platform "hppa" "hppa"
                 (bv "\x7f\x45\x4c\x46\x01\x02\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x0f")
                 (bv "\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff")))

(define %qemu-platforms
  (list %i386 %i486 %alpha %arm %sparc32plus %ppc %ppc64 %ppc64le %m68k
        %mips %mipsel %mipsn32 %mipsn32el %mips64 %mips64el
        %riscv32 %riscv64 %sh4 %sh4eb %s390x %aarch64 %hppa))

(define (lookup-qemu-platforms . names)
  "Return the list of QEMU platforms that match NAMES--a list of names such as
\"arm\", \"hppa\", etc."
  (filter (lambda (platform)
            (member (qemu-platform-name platform) names))
          %qemu-platforms))

(define-record-type* <qemu-binfmt-configuration>
  qemu-binfmt-configuration make-qemu-binfmt-configuration
  qemu-binfmt-configuration?
  (qemu        qemu-binfmt-configuration-qemu
               (default qemu))
  (platforms   qemu-binfmt-configuration-platforms
               (default '()))                     ;safest default
  (guix-support? qemu-binfmt-configuration-guix-support?
                 (default #f)))

(define (qemu-platform->binfmt qemu platform)
  "Return a gexp that evaluates to a binfmt string for PLATFORM, using the
given QEMU package."
  (define (bytevector->binfmt-string bv)
    ;; Return a binfmt-friendly string representing BV.  Hex-encode every
    ;; character, in particular because the doc notes "that you must escape
    ;; any NUL bytes; parsing halts at the first one".
    (string-concatenate
     (map (lambda (n)
            (string-append "\\x"
                           (string-pad (number->string n 16) 2 #\0)))
          (bytevector->u8-list bv))))

  (match platform
    (($ <qemu-platform> name family magic mask)
     ;; See 'Documentation/binfmt_misc.txt' in the kernel.
     #~(string-append ":qemu-" #$name ":M::"
                      #$(bytevector->binfmt-string magic)
                      ":" #$(bytevector->binfmt-string mask)
                      ":" #$(file-append qemu "/bin/qemu-" name)
                      ":"                         ;FLAGS go here
                      ))))

(define %binfmt-mount-point
  (file-system-mount-point %binary-format-file-system))

(define %binfmt-register-file
  (string-append %binfmt-mount-point "/register"))

(define qemu-binfmt-shepherd-services
  (match-lambda
    (($ <qemu-binfmt-configuration> qemu platforms)
     (list (shepherd-service
            (provision '(qemu-binfmt))
            (documentation "Install binfmt_misc handlers for QEMU.")
            (requirement '(file-system-/proc/sys/fs/binfmt_misc))
            (start #~(lambda ()
                       ;; Register the handlers for all of PLATFORMS.
                       (for-each (lambda (str)
                                   (call-with-output-file
                                       #$%binfmt-register-file
                                     (lambda (port)
                                       (display str port))))
                                 (list
                                  #$@(map (cut qemu-platform->binfmt qemu
                                               <>)
                                          platforms)))
                       #t))
            (stop #~(lambda (_)
                      ;; Unregister the handlers.
                      (for-each (lambda (name)
                                  (let ((file (string-append
                                               #$%binfmt-mount-point
                                               "/qemu-" name)))
                                    (call-with-output-file file
                                      (lambda (port)
                                        (display "-1" port)))))
                                '#$(map qemu-platform-name platforms))
                      #f)))))))

(define qemu-binfmt-guix-chroot
  (match-lambda
    ;; Add QEMU and its dependencies to the guix-daemon chroot so that our
    ;; binfmt_misc handlers work in the chroot (otherwise 'execve' would fail
    ;; with ENOENT.)
    ;;
    ;; The 'F' flag of binfmt_misc is meant to address this problem by loading
    ;; the interpreter upfront rather than lazily, but apparently that is
    ;; insufficient (perhaps it loads the 'qemu-ARCH' binary upfront but looks
    ;; up its dependencies lazily?).
    (($ <qemu-binfmt-configuration> qemu platforms guix?)
     (if guix? (list qemu) '()))))

(define qemu-binfmt-service-type
  ;; TODO: Make a separate binfmt_misc service out of this?
  (service-type (name 'qemu-binfmt)
                (extensions
                 (list (service-extension file-system-service-type
                                          (const
                                           (list %binary-format-file-system)))
                       (service-extension shepherd-root-service-type
                                          qemu-binfmt-shepherd-services)
                       (service-extension guix-service-type
                                          qemu-binfmt-guix-chroot)))
                (default-value (qemu-binfmt-configuration))
                (description
                 "This service supports transparent emulation of binaries
compiled for other architectures using QEMU and the @code{binfmt_misc}
functionality of the kernel Linux.")))

;;;
;;; Secrets for guest VMs.
;;;

(define (secret-service-activation port)
  "Return an activation snippet that fetches sensitive material at local PORT,
over TCP.  Reboot upon failure."
  (with-imported-modules '((gnu build secret-service)
                           (guix build utils))
    #~(begin
        (use-modules (gnu build secret-service))
        (let ((sent (secret-service-receive-secrets #$port)))
          (unless sent
            (sleep 3)
            (reboot))))))

(define secret-service-type
  (service-type
   (name 'secret-service)
   (extensions (list (service-extension activation-service-type
                                        secret-service-activation)))
   (description
    "This service fetches secret key and other sensitive material over TCP at
boot time.  This service is meant to be used by virtual machines (VMs) that
can only be accessed by their host.")))

(define (secret-service-operating-system os)
  "Return an operating system based on OS that includes the secret-service,
that will be listening to receive secret keys on port 1004, TCP."
  (operating-system
    (inherit os)
    (services (cons (service secret-service-type 1004)
                    (operating-system-user-services os)))))

;;;
;;; The Hurd in VM service: a Childhurd.
;;;

(define %hurd-vm-operating-system
  (operating-system
    (inherit %hurd-default-operating-system)
    (host-name "childhurd")
    (timezone "Europe/Amsterdam")
    (bootloader (bootloader-configuration
                 (bootloader grub-minimal-bootloader)
                 (target "/dev/vda")
                 (timeout 0)))
    (services (cons*
               (service openssh-service-type
                        (openssh-configuration
                         (openssh openssh-sans-x)
                         (use-pam? #f)
                         (port-number 2222)
                         (permit-root-login #t)
                         (allow-empty-passwords? #t)
                         (password-authentication? #t)))
               %base-services/hurd))))

(define-record-type* <hurd-vm-configuration>
  hurd-vm-configuration make-hurd-vm-configuration
  hurd-vm-configuration?
  (os          hurd-vm-configuration-os                 ;<operating-system>
               (default %hurd-vm-operating-system))
  (qemu        hurd-vm-configuration-qemu               ;<package>
               (default qemu-minimal))
  (image       hurd-vm-configuration-image              ;string
               (thunked)
               (default (hurd-vm-disk-image this-record)))
  (disk-size   hurd-vm-configuration-disk-size          ;number or 'guess
               (default 'guess))
  (memory-size hurd-vm-configuration-memory-size        ;number
               (default 512))
  (options     hurd-vm-configuration-options            ;list of string
               (default `("--snapshot")))
  (id          hurd-vm-configuration-id                 ;#f or integer [1..]
               (default #f))
  (net-options hurd-vm-configuration-net-options        ;list of string
               (thunked)
               (default (hurd-vm-net-options this-record)))
  (secret-root hurd-vm-configuration-secret-root        ;string
               (default "/etc/childhurd")))

(define (hurd-vm-disk-image config)
  "Return a disk-image for the Hurd according to CONFIG.  The secret-service
is added to the OS specified in CONFIG."
  (let ((os (secret-service-operating-system (hurd-vm-configuration-os config)))
        (disk-size (hurd-vm-configuration-disk-size config)))
    (system-image
     (image
      (inherit hurd-disk-image)
      (size disk-size)
      (operating-system os)))))

(define (hurd-vm-port config base)
  "Return the forwarded vm port for this childhurd config."
  (let ((id (or (hurd-vm-configuration-id config) 0)))
    (+ base (* 1000 id))))
(define %hurd-vm-secrets-port 11004)
(define %hurd-vm-ssh-port 10022)
(define %hurd-vm-vnc-port 15900)

(define (hurd-vm-net-options config)
  `("--device" "rtl8139,netdev=net0"
    "--netdev"
    ,(string-append "user,id=net0"
                    ",hostfwd=tcp:127.0.0.1:"
                    (number->string (hurd-vm-port config %hurd-vm-secrets-port))
                    "-:1004"
                    ",hostfwd=tcp:127.0.0.1:"
                    (number->string (hurd-vm-port config %hurd-vm-ssh-port))
                    "-:2222"
                    ",hostfwd=tcp:127.0.0.1:"
                    (number->string (hurd-vm-port config %hurd-vm-vnc-port))
                    "-:5900")))

(define (hurd-vm-shepherd-service config)
  "Return a <shepherd-service> for a Hurd in a Virtual Machine with CONFIG."

  (let ((image       (hurd-vm-configuration-image config))
        (qemu        (hurd-vm-configuration-qemu config))
        (memory-size (hurd-vm-configuration-memory-size config))
        (options     (hurd-vm-configuration-options config))
        (id          (hurd-vm-configuration-id config))
        (net-options (hurd-vm-configuration-net-options config))
        (provisions  '(hurd-vm childhurd)))

    (define vm-command
      #~(list
         (string-append #$qemu "/bin/qemu-system-i386")
         #$@(if (file-exists? "/dev/kvm") '("--enable-kvm") '())
         "-m" (number->string #$memory-size)
         #$@net-options
         #$@options
         "--hda" #+image))

    (list
     (shepherd-service
      (documentation "Run the Hurd in a Virtual Machine: a Childhurd.")
      (provision (if id
                     (map
                      (cute symbol-append <>
                            (string->symbol (number->string id)))
                      provisions)
                     provisions))
      (requirement '(loopback networking user-processes))
      (start
       (with-imported-modules
           (source-module-closure '((gnu build secret-service)
                                    (guix build utils)))
         #~(let ((spawn (make-forkexec-constructor #$vm-command)))
             (lambda _
               (let ((pid (spawn))
                     (port #$(hurd-vm-port config %hurd-vm-secrets-port))
                     (root #$(hurd-vm-configuration-secret-root config)))
                 (catch #t
                   (lambda _
                     (secret-service-send-secrets port root))
                   (lambda (key . args)
                     (kill (- pid) SIGTERM)
                     (apply throw key args)))
                 pid)))))
      (modules `((gnu build secret-service)
                 (guix build utils)
                 ,@%default-modules))
      (stop  #~(make-kill-destructor))))))

(define hurd-vm-service-type
  (service-type
   (name 'hurd-vm)
   (extensions (list (service-extension shepherd-root-service-type
                                        hurd-vm-shepherd-service)))
   (default-value (hurd-vm-configuration))
   (description
    "Provide a Virtual Machine running the GNU/Hurd.")))