email_server: Setup /var/mail, drop home setup view

Creating home directories is no longer necessary. We store all mail in /var/mail
and don't allow use of direct access to mail folder.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/modules/email_server/__init__.py

@@ -3,7 +3,6 @@
 
 import logging
 
-from django.urls import reverse_lazy
 from django.utils.translation import gettext_lazy as _
 
 import plinth.app
@@ -112,13 +111,6 @@ class EmailServerApp(plinth.app.App):
             parent_url_name='apps')
         self.add(menu_item)
 
-        shortcut = plinth.frontpage.Shortcut(
-            'shortcut_' + self.app_id, name=info.name,
-            short_description=info.short_description, icon='roundcube',
-            url=reverse_lazy('email_server:my_mail'), clients=manifest.clients,
-            login_required=True)
-        self.add(shortcut)
-
     def _add_daemons(self):
         for srvname in managed_services:
             # Construct `listen_ports` parameter for the daemon
@@ -170,6 +162,7 @@ def setup(helper, old_version=None):
     helper.install(packages_bloat, skip_recommends=True)
 
     # Setup
+    helper.call('post', audit.home.repair)
     helper.call('post', audit.domain.repair)
     helper.call('post', audit.ldap.repair)
     helper.call('post', audit.spam.repair)

plinth/modules/email_server/audit/home.py

@@ -1,70 +1,22 @@
 # SPDX-License-Identifier: AGPL-3.0-or-later
+"""Privileged actions to setup users' dovecot mail home directory."""
 
-import logging
-import os
-import pwd
 import subprocess
 
-from django.core.exceptions import ValidationError
-from django.utils.translation import gettext_lazy as _
-
-from plinth.actions import superuser_run
-from plinth.errors import ActionError
-from plinth.modules.email_server import interproc
-
-logger = logging.getLogger(__name__)
+from plinth import actions
 
 
-def exists_nam(username):
-    """Returns True if the user's home directory exists"""
-    try:
-        passwd = pwd.getpwnam(username)
-    except KeyError as e:
-        raise ValidationError(_('User does not exist')) from e
-    return _exists(passwd)
+def repair():
+    """Set correct permissions on /var/mail/ directory.
+
+    For each user, /var/mail/<user> is the 'dovecot mail home' for that user.
+    Dovecot creates new directories with the same permissions as the parent
+    directory. Ensure that 'others' can access /var/mail/.
+
+    """
+    actions.superuser_run('email_server', ['home', 'set_up'])
 
 
-def exists_uid(uid_number):
-    """Returns True if the user's home directory exists"""
-    try:
-        passwd = pwd.getpwuid(uid_number)
-    except KeyError as e:
-        raise ValidationError(_('User does not exist')) from e
-    return _exists(passwd)
-
-
-def _exists(passwd):
-    return os.path.exists(passwd.pw_dir)
-
-
-def put_nam(username):
-    """Create a home directory for the user (identified by username)"""
-    _put('nam', username)
-
-
-def put_uid(uid_number):
-    """Create a home directory for the user (identified by UID)"""
-    _put('uid', str(uid_number))
-
-
-def _put(arg_type, user_info):
-    try:
-        superuser_run('email_server', ['home', 'mk', arg_type, user_info])
-    except ActionError as e:
-        raise RuntimeError('Action script failure') from e
-
-
-def action_mk(arg_type, user_info):
-    if arg_type == 'nam':
-        passwd = pwd.getpwnam(user_info)
-    elif arg_type == 'uid':
-        passwd = pwd.getpwuid(int(user_info))
-    else:
-        raise ValueError('Unknown arg_type')
-
-    args = ['sudo', '-n', '--user=#' + str(passwd.pw_uid)]
-    args.extend(['/bin/sh', '-c', 'mkdir -p ~'])
-    completed = subprocess.run(args, capture_output=True, check=False)
-    if completed.returncode != 0:
-        interproc.log_subprocess(completed)
-        raise OSError('Could not create home directory')
+def action_set_up():
+    """Run chmod on /var/mail to remove all permissions for 'others'."""
+    subprocess.run(['chmod', 'o-rwx', '/var/mail'], check=True)

plinth/modules/email_server/templates/email_server.html

@@ -19,10 +19,6 @@
     {% trans "Manage Spam" %}
     <span class="fa fa-external-link"></span>
   </a>
-  <a class="btn btn-default" role="button"
-     href="{% url 'email_server:my_mail' %}">
-    {% trans "Setup My Home" %}
-  </a>
   <a class="btn btn-default" role="button"
      href="{% url 'email_server:aliases' %}">
     {% trans "Manage Aliases" %}

plinth/modules/email_server/templates/my_mail.html

@@ -1,30 +0,0 @@
-{% extends "base.html" %}
-{% comment %}
-# SPDX-License-Identifier: AGPL-3.0-or-later
-{% endcomment %}
-
-{% load i18n %}
-
-{% block content %}
-
-  <h2>Setup My Home</h2>
-
-  {% if not has_homedir %}
-    <p>
-      {% trans "You do not have a home directory." %}
-      <span>
-        {% trans "Create one to begin receiving emails." %}
-      </span>
-    </p>
-
-    <form action="{{ request.path }}" method="post">
-      {% csrf_token %}
-      <button class="btn btn-primary" type="submit" name="btn_mkhome">
-        {% trans "Create home directory" %}
-      </button>
-    </form>
-  {% else %}
-    <p>{% trans "Your home directory is ready to receive emails." %}</p>
-  {% endif %}
-
-{% endblock %}

plinth/modules/email_server/urls.py

@@ -10,8 +10,6 @@ urlpatterns = [
     path('apps/email_server/', views.EmailServerView.as_view(), name='index'),
     path('apps/email_server/domains', views.DomainsView.as_view(),
          name='domains'),
-    path('apps/email_server/my_mail',
-         non_admin_view(views.MyMailView.as_view()), name='my_mail'),
     path('apps/email_server/my_aliases',
          non_admin_view(views.AliasView.as_view()), name='aliases'),
     path('apps/email_server/config.xml', public(views.XmlView.as_view())),

plinth/modules/email_server/views.py

@@ -99,20 +99,6 @@ class EmailServerView(ExceptionsMixin, AppView):
             plinth.actions.superuser_run('service', ['reload', service])
 
 
-class MyMailView(TemplateView):
-    template_name = 'my_mail.html'
-
-    def get_context_data(self, *args, **kwargs):
-        context = super().get_context_data(*args, **kwargs)
-        nam = self.request.user.username
-        context['has_homedir'] = audit.home.exists_nam(nam)
-        return context
-
-    def post(self, request):
-        audit.home.put_nam(request.user.username)
-        return self.render_to_response(self.get_context_data())
-
-
 class AliasView(FormView):
     """View to create, list, enable, disable and delete aliases.