Add support for systemd-networkd

When masking udev/systemd predictable network interface
names, the initramfs must be updated or the mask will not
be effective.

Add support for systemd-networkd using predictable network
interface names - can be extended using customisation scripts.

5 files changed, 138 insertions, 46 deletions

diff --git a/bin/vmdebootstrap b/bin/vmdebootstrap
index 0a08eb9..805b347 100755
--- a/bin/vmdebootstrap
+++ b/bin/vmdebootstrap
@@ -35,8 +35,9 @@ from vmdebootstrap.extlinux import ExtLinux
 from vmdebootstrap.codenames import Codenames
 from vmdebootstrap.filesystem import Filesystem
 from vmdebootstrap.uefi import Uefi
+from vmdebootstrap.network import Networking
 
-__version__ = '1.3'
+__version__ = '1.4'
 
 # pylint: disable=invalid-name,line-too-long,missing-docstring
 
@@ -56,6 +57,7 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
             GrubHandler.name: GrubHandler(),
             ExtLinux.name: ExtLinux(),
             Filesystem.name: Filesystem(),
+            Networking.name: Networking(),
         }
 
     def add_settings(self):
@@ -123,8 +125,11 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
         self.settings.boolean(['pkglist'], 'Create a list of package names '
                               'included in the image.')
         self.settings.boolean(['no-acpid'], 'do not install the acpid package', default=False)
-        self.settings.boolean(['no-update-initramfs'], 'Skip running update-initramfs', default=False)
+        self.settings.boolean(['update-initramfs'], 
+                              'Run update-initramfs after customisation', default=True)
         self.settings.boolean(['convert-qcow2'], 'Convert final image to qcow2', default=False)
+        self.settings.boolean(['systemd-networkd'], 'Use Predictable Network '
+                              'Interface Names', default=True)
         self.settings.boolean(['dry-run'], 'do not build, just test the options', default=False)
 
     def process_args(self, args):  # pylint: disable=too-many-branches,too-many-statements
@@ -161,6 +166,13 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
         if self.settings['squash'] and self.settings['tarball']:
             raise cliapp.AppException(
                 'Use --squash or --tarball, not both.')
+        if not distro.was_oldstable(datetime.date(2015, 4, 26)):
+            if not self.settings['systemd-networkd'] and\
+                    self.settings['no-update-initramfs']:
+                raise cliapp.AppException(
+                    'Disabling systemd-networkd for jessie and later '
+                    'requires updating the initramfs.')
+
         uefi = self.handlers[Uefi.name]
         oldstable = distro.was_oldstable(datetime.date(2015, 4, 26))
         uefi.check_settings(oldstable=oldstable)
@@ -234,7 +246,7 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
         # only append for wheezy (which became oldstable on 2015.04.25)
         if distro.was_oldstable(datetime.date(2015, 4, 26)):
             base.append_serial_console(rootdir)
-        elif self.settings['serial-console']:
+        elif self.settings['serial-console'] and not self.settings['grub']:
             base.message("Skipping setting serial console- wheezy only.")
         self.optimize_image(rootdir)
 
@@ -258,7 +270,11 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
             base.set_root_password(rootdir)
             base.create_users(rootdir)
             filesystem.remove_udev_persistent_rules()
-            self.setup_networking(rootdir)
+            if distro.was_oldstable(datetime.date(2015, 4, 26)):
+                network.setup_wheezy_networking(rootdir)
+            else:
+                network.setup_networking(rootdir)
+                network.systemd_support(rootdir)
             filesystem.configure_apt()
             base.customize(rootdir)
             cleanup_apt_cache(rootdir)
@@ -462,35 +478,6 @@ class VmDebootstrap(cliapp.Application):  # pylint: disable=too-many-public-meth
             self.runcmd_unchecked(['dd', 'if=/dev/zero', 'of=' + zeros, 'bs=1M'])
             runcmd(['rm', '-f', zeros])
 
-    def setup_networking(self, rootdir):
-        base = self.handlers[Base.name]
-        base.message('Setting up networking')
-        distro = self.handlers[Codenames.name]
-        ifc_file = os.path.join(rootdir, 'etc', 'network', 'interfaces')
-        ifc_d = os.path.join(rootdir, 'etc', 'network', 'interfaces.d')
-
-        # unconditionally write for wheezy (which became oldstable on 2015.04.25)
-        if distro.was_oldstable(datetime.date(2015, 4, 26)):
-            with open(ifc_file, 'w') as netfile:
-                netfile.write('source /etc/network/interfaces.d/*\n')
-        elif not os.path.exists(ifc_file):
-            with open(ifc_file, 'a') as netfile:
-                netfile.write('source-directory /etc/network/interfaces.d\n')
-
-        if not os.path.exists(ifc_d):
-            os.mkdir(ifc_d)
-        ethpath = os.path.join(ifc_d, 'setup')
-        with open(ethpath, 'w') as eth:
-            eth.write('auto lo\n')
-            eth.write('iface lo inet loopback\n')
-
-            if self.settings['enable-dhcp']:
-                eth.write('\n')
-                eth.write('auto eth0\n')
-                eth.write('iface eth0 inet dhcp\n')
-                # force predictable interface names
-                base.mask_udev_predictable_rules(rootdir)
-
     def cleanup_system(self):
         base = self.handlers[Base.name]
         # Clean up after any errors.
diff --git a/vmdebootstrap/base.py b/vmdebootstrap/base.py
index 4ce5236..43d5a3e 100644
--- a/vmdebootstrap/base.py
+++ b/vmdebootstrap/base.py
@@ -204,14 +204,3 @@ class Base(object):
             if self.settings['kernel-package']:
                 packages.append(self.settings['kernel-package'])
         return packages
-
-    def mask_udev_predictable_rules(self, rootdir):
-        """
-        This can be reset later but to get networking using immediately
-        on boot, the interface we're going to use must be known
-        http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/
-        """
-        self.message('Disabling systemd predictable interface names')
-        udev_path = os.path.join(
-            'etc', 'udev', 'rules.d', '80-net-setup-link.rules')
-        runcmd(['chroot', rootdir, 'ln', '-s', '/dev/null', udev_path])
diff --git a/vmdebootstrap/filesystem.py b/vmdebootstrap/filesystem.py
index 106fa56..ad7575c 100644
--- a/vmdebootstrap/filesystem.py
+++ b/vmdebootstrap/filesystem.py
@@ -70,11 +70,15 @@ class Filesystem(Base):
         runcmd(["chown", "-R", self.settings["owner"], filename])
 
     def update_initramfs(self):
+        if not rootdir:
+            raise cliapp.AppException("rootdir not set")
+        if not os.path.exists(
+                os.path.join(rootdir, 'usr', 'sbin', 'update-initramfs')):
+            self.message("Error: Unable to run update-initramfs.")
+            return
         if not self.settings['no-update-initramfs']:
             return
         rootdir = self.devices['rootdir']
-        if not rootdir:
-            raise cliapp.AppException("rootdir not set")
         cmd = os.path.join('usr', 'sbin', 'update-initramfs')
         if os.path.exists(os.path.join(str(rootdir), cmd)):
             self.message("Updating the initramfs")
diff --git a/vmdebootstrap/network.py b/vmdebootstrap/network.py
new file mode 100644
index 0000000..740dede
--- /dev/null
+++ b/vmdebootstrap/network.py
@@ -0,0 +1,105 @@
+"""
+  Wrapper for network support
+"""
+# -*- coding: utf-8 -*-
+#
+#  network.py
+#  
+#  Copyright 2015 Neil Williams <codehelp@debian.org>
+#  
+#  This program 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 2 of the License, or
+#  (at your option) any later version.
+#  
+#  This program 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 this program; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+#  MA 02110-1301, USA.
+#  
+#  
+
+import os
+from vmdebootstrap.base import (
+    Base,
+    runcmd,
+)
+
+# pylint: disable=missing-docstring
+
+
+class Networking(Base):
+
+    name = 'networking'
+
+    def _write_network_interfaces(self, rootdir, line):
+        self.message('Setting up networking')
+        ifc_d = os.path.join(rootdir, 'etc', 'network', 'interfaces.d')
+        ifc_file = os.path.join(rootdir, 'etc', 'network', 'interfaces')
+        with open(ifc_file, 'w') as netfile:
+            netfile.write(line)
+        if not os.path.exists(ifc_d):
+            os.mkdir(ifc_d)
+        with open(ethpath, 'w') as eth:
+            eth.write('auto lo\n')
+            eth.write('iface lo inet loopback\n')
+            if self.settings['enable-dhcp']:
+                eth.write('\n')
+                eth.write('auto eth0\n')
+                eth.write('iface eth0 inet dhcp\n')
+
+    def setup_wheezy_networking(self, rootdir):
+        """
+        unconditionally write for wheezy
+        (which became oldstable on 2015.04.25)
+        """
+        self._write_network_interfaces(
+            rootdir, 'source /etc/network/interfaces.d/*\n')
+
+    def setup_networking(self, rootdir):
+        self._write_network_interfaces(
+            rootdir, 'source-directory /etc/network/interfaces.d\n')
+
+    def systemd_support(self, rootdir):
+        """
+        Handle the systemd-networkd setting
+        """
+        if self.settings['systemd-networkd']:
+            self.enable_systemd_networkd(rootdir)
+        else:
+            self.mask_udev_predictable_rules(rootdir)
+
+    def mask_udev_predictable_rules(self, rootdir):
+        """
+        This can be reset later but to get networking using eth0
+        immediately upon boot, the interface we're going to use must
+        be known and must update the initramfs after setting up the
+        mask.
+        """
+        self.message('Disabling systemd predictable interface names')
+        udev_path = os.path.join(
+            'etc', 'udev', 'rules.d', '80-net-setup-link.rules')
+        runcmd(['chroot', rootdir, 'ln', '-s', '/dev/null', udev_path])
+
+    def enable_systemd_networkd(self, rootdir):
+        """
+        Get networking working immediately on boot, allow any en* interface
+        to be enabled by systemd-networkd using DHCP
+        https://coreos.com/os/docs/latest/network-config-with-networkd.html
+        http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/
+        """
+        if not self.settings['enable-dhcp']:
+            return
+        self.message('Enabling systemd-networkd for DHCP')
+        ethpath = os.path.join(rootdir, 'etc', 'systemd', 'network', '99-dhcp.network')
+        with open(ethpath, 'w') as eth:
+            eth.write('[Match]\n')
+            eth.write('Name=en*\n')
+            eth.write('\n[Network]\n')
+            eth.write('DHCP=yes\n')
+        runcmd(['chroot', rootdir, 'systemctl', 'enable', 'systemd-networkd'])
diff --git a/yarns/200-fast-tests.yarn b/yarns/200-fast-tests.yarn
index 796535e..803d09d 100644
--- a/yarns/200-fast-tests.yarn
+++ b/yarns/200-fast-tests.yarn
@@ -167,3 +167,10 @@ verify that vmdebootstrap parses the command line correctly.
     ... --squash=FOO --tarball=FOO --arch=amd64 --dry-run
     THEN vmdebootstrap exited with a non-zero exit code
     AND vmdebootstrap wrote an error message matching not both
+
+    SCENARIO masking systemd-networkd without updating initramfs
+    ASSUMING fast tests are requested
+    WHEN user attempts to run vmdebootstrap
+    ... --image=FOO --no-systemd-networkd --no-update-initramfs --dry-run
+    THEN vmdebootstrap exited with a non-zero exit code
+    AND vmdebootstrap wrote an error message matching requires updating the