services: tor: Add a system test.

* gnu/services/networking.scm (tor-configuration->torrc): Set PidFile to
/var/run/tor/tor.pid in the base torrc configuration.
(tor-shepherd-service) <start>: Call make-forkexec-constructor/container with
a new #:pid-file argument to tell Shepherd where to find the PID file.  Add a
a new <file-system-mapping> to its existing #:mappings argument to share
/var/run/tor with the the container.
(tor-hidden-services-activation): Update docstring.  Create /var/run/tor and
set its permissions so only the tor user can access it.
* gnu/tests/networking.scm (%test-tor, %tor-os): New variables.
(run-tor-test): New procedure.

gnu/services/networking.scm

@@ -7,6 +7,7 @@
 ;;; Copyright © 2017 Thomas Danckaert <post@thomasdanckaert.be>
 ;;; Copyright © 2017 Marius Bakke <mbakke@fastmail.com>
 ;;; Copyright © 2018 Tobias Geerinckx-Rice <me@tobias.gr>
+;;; Copyright © 2018 Chris Marusich <cmmarusich@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -612,6 +613,7 @@ (define (tor-configuration->torrc config)
 ### These lines were generated from your system configuration:
 User tor
 DataDirectory /var/lib/tor
+PidFile /var/run/tor/tor.pid
 Log notice syslog\n" port)
 
                 (for-each (match-lambda
@@ -639,7 +641,7 @@ (define (tor-configuration->torrc config)
                 #t))))))))
 
 (define (tor-shepherd-service config)
-  "Return a <shepherd-service> running TOR."
+  "Return a <shepherd-service> running Tor."
   (match config
     (($ <tor-configuration> tor)
      (let ((torrc (tor-configuration->torrc config)))
@@ -665,12 +667,17 @@ (define (tor-shepherd-service config)
                                             (writable? #t))
                                            (file-system-mapping
                                             (source "/dev/log") ;for syslog
-                                            (target source)))))
+                                            (target source))
+                                           (file-system-mapping
+                                            (source "/var/run/tor")
+                                            (target source)
+                                            (writable? #t)))
+                          #:pid-file "/var/run/tor/tor.pid"))
                 (stop #~(make-kill-destructor))
                 (documentation "Run the Tor anonymous network overlay."))))))))
 
 (define (tor-hidden-service-activation config)
-  "Return the activation gexp for SERVICES, a list of hidden services."
+  "Set up directories for Tor and its hidden services, if any."
   #~(begin
       (use-modules (guix build utils))
 
@@ -686,6 +693,15 @@ (define (initialize service)
           ;; The daemon bails out if we give wider permissions.
           (chmod directory #o700)))
 
+      ;; Allow Tor to write its PID file.
+      (mkdir-p "/var/run/tor")
+      (chown "/var/run/tor" (passwd:uid %user) (passwd:gid %user))
+      ;; Set the group permissions to rw so that if the system administrator
+      ;; has specified UnixSocksGroupWritable=1 in their torrc file, members
+      ;; of the "tor" group will be able to use the SOCKS socket.
+      (chmod "/var/run/tor" #o750)
+
+      ;; Allow Tor to access the hidden services' directories.
       (mkdir-p "/var/lib/tor")
       (chown "/var/lib/tor" (passwd:uid %user) (passwd:gid %user))
       (chmod "/var/lib/tor" #o700)

gnu/tests/networking.scm

@@ -30,7 +30,7 @@ (define-module (gnu tests networking)
   #:use-module (gnu packages bash)
   #:use-module (gnu packages networking)
   #:use-module (gnu services shepherd)
-  #:export (%test-inetd %test-openvswitch %test-dhcpd))
+  #:export (%test-inetd %test-openvswitch %test-dhcpd %test-tor))
 
 (define %inetd-os
   ;; Operating system with 2 inetd services.
@@ -339,3 +339,57 @@ (define %test-dhcpd
    (name "dhcpd")
    (description "Test a running DHCP daemon configuration.")
    (value (run-dhcpd-test))))
+
+
+;;;
+;;; Services related to Tor
+;;;
+
+(define %tor-os
+  (simple-operating-system
+   (tor-service)))
+
+(define (run-tor-test)
+  (define os
+    (marionette-operating-system %tor-os
+                                 #:imported-modules '((gnu services herd))
+                                 #:requirements '(tor)))
+
+  (define test
+    (with-imported-modules '((gnu build marionette))
+      #~(begin
+          (use-modules (gnu build marionette)
+                       (ice-9 popen)
+                       (ice-9 rdelim)
+                       (srfi srfi-64))
+
+          (define marionette
+            (make-marionette (list #$(virtual-machine os))))
+
+          (mkdir #$output)
+          (chdir #$output)
+
+          (test-begin "tor")
+
+          (test-assert "tor is alive"
+            (marionette-eval
+             '(begin
+                (use-modules (gnu services herd)
+                             (srfi srfi-1))
+                (live-service-running
+                 (find (lambda (live)
+                         (memq 'tor
+                               (live-service-provision live)))
+                       (current-services))))
+             marionette))
+
+          (test-end)
+          (exit (= (test-runner-fail-count (test-runner-current)) 0)))))
+
+  (gexp->derivation "tor-test" test))
+
+(define %test-tor
+  (system-test
+   (name "tor")
+   (description "Test a running Tor daemon configuration.")
+   (value (run-tor-test))))