OS-55: Inject network settings in linux images

6 files changed, 110 insertions, 27 deletions

diff --git a/nova/virt/conn_common.py b/nova/virt/conn_common.py
new file mode 100644
index 000000000..bd9ed7794
--- /dev/null
+++ b/nova/virt/conn_common.py
@@ -0,0 +1,50 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright (c) 2010 Citrix Systems, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from nova import context
+from nova import db
+from nova import exception
+from nova import flags
+from nova import log as logging
+from nova import utils
+
+LOG = logging.getLogger('nova.virt.conn_common')
+FLAGS = flags.FLAGS
+
+flags.DEFINE_string('injected_network_template',
+                    utils.abspath('virt/interfaces.template'),
+                    'Template file for injected network')
+                    
+def get_injectables(inst):
+    key = str(inst['key_data'])
+    net = None
+    network_ref = db.network_get_by_instance(context.get_admin_context(),
+                                             inst['id'])
+    if network_ref['injected']:
+        admin_context = context.get_admin_context()
+        address = db.instance_get_fixed_address(admin_context, inst['id'])
+        ra_server = network_ref['ra_server']
+        if not ra_server:
+            ra_server = "fd00::"
+        with open(FLAGS.injected_network_template) as f:
+            net = f.read() % {'address': address,
+                              'netmask': network_ref['netmask'],
+                              'gateway': network_ref['gateway'],
+                              'broadcast': network_ref['broadcast'],
+                              'dns': network_ref['dns'],
+                              'ra_server': ra_server}
+
+    return key, net
diff --git a/nova/virt/disk.py b/nova/virt/disk.py
index c5565abfa..88b05f0c0 100644
--- a/nova/virt/disk.py
+++ b/nova/virt/disk.py
@@ -92,11 +92,7 @@ def inject_data(image, key=None, net=None, partition=None, nbd=False):
                                       % err)
 
             try:
-                if key:
-                    # inject key file
-                    _inject_key_into_fs(key, tmpdir)
-                if net:
-                    _inject_net_into_fs(net, tmpdir)
+                inject_data_into_fs(tmpdir, key, net, execute)
             finally:
                 # unmount device
                 utils.execute('sudo umount %s' % mapped_device)
@@ -158,8 +154,17 @@ def _allocate_device():
 def _free_device(device):
     _DEVICES.append(device)
 
+def inject_data_into_fs(fs, key, net, execute):
+    """Injects data into a filesystem already mounted by the caller.
+    Virt connections can call this directly if they mount their fs
+    in a different way to inject_data
+    """
+    if key:
+        _inject_key_into_fs(key, fs, execute=execute)
+    if net:
+        _inject_net_into_fs(net, fs, execute=execute)
 
-def _inject_key_into_fs(key, fs):
+def _inject_key_into_fs(key, fs, execute=None):
     """Add the given public ssh key to root's authorized_keys.
 
     key is an ssh key string.
@@ -173,7 +178,7 @@ def _inject_key_into_fs(key, fs):
     utils.execute('sudo tee -a %s' % keyfile, '\n' + key.strip() + '\n')
 
 
-def _inject_net_into_fs(net, fs):
+def _inject_net_into_fs(net, fs, execute=None):
     """Inject /etc/network/interfaces into the filesystem rooted at fs.
 
     net is the contents of /etc/network/interfaces.
diff --git a/nova/virt/libvirt_conn.py b/nova/virt/libvirt_conn.py
index 4e0fd106f..45d8754ab 100644
--- a/nova/virt/libvirt_conn.py
+++ b/nova/virt/libvirt_conn.py
@@ -62,6 +62,7 @@ from nova.compute import instance_types
 from nova.compute import power_state
 from nova.virt import disk
 from nova.virt import images
+from nova.virt import conn_common
 
 libvirt = None
 libxml2 = None
@@ -74,9 +75,7 @@ FLAGS = flags.FLAGS
 flags.DEFINE_string('rescue_image_id', 'ami-rescue', 'Rescue ami image')
 flags.DEFINE_string('rescue_kernel_id', 'aki-rescue', 'Rescue aki image')
 flags.DEFINE_string('rescue_ramdisk_id', 'ari-rescue', 'Rescue ari image')
-flags.DEFINE_string('injected_network_template',
-                    utils.abspath('virt/interfaces.template'),
-                    'Template file for injected network')
+
 flags.DEFINE_string('libvirt_xml_template',
                     utils.abspath('virt/libvirt.xml.template'),
                     'Libvirt XML Template')
@@ -622,23 +621,8 @@ class LibvirtConnection(object):
         if not inst['kernel_id']:
             target_partition = "1"
 
-        key = str(inst['key_data'])
-        net = None
-        network_ref = db.network_get_by_instance(context.get_admin_context(),
-                                                 inst['id'])
-        if network_ref['injected']:
-            admin_context = context.get_admin_context()
-            address = db.instance_get_fixed_address(admin_context, inst['id'])
-            ra_server = network_ref['ra_server']
-            if not ra_server:
-                ra_server = "fd00::"
-            with open(FLAGS.injected_network_template) as f:
-                net = f.read() % {'address': address,
-                                  'netmask': network_ref['netmask'],
-                                  'gateway': network_ref['gateway'],
-                                  'broadcast': network_ref['broadcast'],
-                                  'dns': network_ref['dns'],
-                                  'ra_server': ra_server}
+        key, net = conn_common.get_injectables(inst)
+
         if key or net:
             inst_name = inst['name']
             img_id = inst.image_id
diff --git a/nova/virt/xenapi/vm_utils.py b/nova/virt/xenapi/vm_utils.py
index 4bbd522c1..70f81b3b6 100644
--- a/nova/virt/xenapi/vm_utils.py
+++ b/nova/virt/xenapi/vm_utils.py
@@ -22,6 +22,7 @@ their attributes like VDIs, VIFs, as well as their lookup functions.
 import os
 import pickle
 import re
+import tempfile
 import time
 import urllib
 from xml.dom import minidom
@@ -33,10 +34,12 @@ from nova import flags
 from nova import log as logging
 from nova import utils
 from nova.auth.manager import AuthManager
+from nova.compute import disk
 from nova.compute import instance_types
 from nova.compute import power_state
 from nova.virt import images
 from nova.virt.xenapi import HelperBase
+from nova.virt import conn_common
 from nova.virt.xenapi.volume_utils import StorageError
 
 
@@ -440,6 +443,39 @@ class VMHelper(HelperBase):
                 return None
 
     @classmethod
+    def preconfigure_instance(cls, session, instance, vdi_ref):
+        """Makes alterations to the image before launching as part of spawn.
+        May also set xenstore values to modify the image behaviour after
+        VM start."""
+        
+        # As mounting the image VDI is expensive, we only want do do it once,
+        # if at all, so determine whether it's required first, and then do
+        # everything
+        mount_required = False
+        key, net = conn_common.get_injectables(instance)
+        if key is not None or net is not None:
+            mount_required = True
+    
+        if mount_required:
+            def _mounted_processing(device):
+                devPath = '/dev/'+device+'1' # Note: Partition 1 hardcoded
+                tmpdir = tempfile.mkdtemp()
+                try:
+                    out, err = utils.execute('sudo mount %s %s' % (devPath, tmpdir))
+                    if err:
+                        raise exception.Error(_('Failed to mount filesystem: %s') % err)
+                    try:
+                        disk.inject_data_into_fs(tmpdir, key, net, utils.execute)
+                    finally:
+                        utils.execute('sudo umount %s' % devPath)
+                finally:
+                    # remove temporary directory
+                    os.rmdir(tmpdir)
+    
+            # FIXME: Check self._session is the type of session this fn wants
+            with_vdi_attached_here(session, vdi_ref, False, _mounted_processing)
+
+    @classmethod
     def compile_info(cls, record):
         """Fill record with VM status information"""
         LOG.info(_("(VM_UTILS) xenserver vm state -> |%s|"),
diff --git a/nova/virt/xenapi/vmops.py b/nova/virt/xenapi/vmops.py
index e84ce20c4..efab9c9ce 100644
--- a/nova/virt/xenapi/vmops.py
+++ b/nova/virt/xenapi/vmops.py
@@ -79,6 +79,9 @@ class VMOps(object):
             disk_image_type = ImageType.DISK
         else:
             disk_image_type = ImageType.DISK_RAW
+        # TODO: Coalesce fetch_image, lookup_image and
+        # manipulate_root_image so requires a single VDI mount/umount
+        # sequence
         vdi_uuid = VMHelper.fetch_image(self._session, instance.id,
             instance.image_id, user, project, disk_image_type)
         vdi_ref = self._session.call_xenapi('VDI.get_by_uuid', vdi_uuid)
@@ -102,6 +105,10 @@ class VMOps(object):
         if network_ref:
             VMHelper.create_vif(self._session, vm_ref,
                                 network_ref, instance.mac_address)
+                                
+        # Alter the image before VM start for, e.g. network injection
+        VMHelper.preconfigure_instance(self._session, instance, vdi_ref)
+        
         LOG.debug(_('Starting VM %s...'), vm_ref)
         self._session.call_xenapi('VM.start', vm_ref, False, False)
         instance_name = instance.name
diff --git a/plugins/xenserver/xenapi/etc/xapi.d/plugins/pluginlib_nova.py b/plugins/xenserver/xenapi/etc/xapi.d/plugins/pluginlib_nova.py
index f51f5fce4..dbbce5c51 100755
--- a/plugins/xenserver/xenapi/etc/xapi.d/plugins/pluginlib_nova.py
+++ b/plugins/xenserver/xenapi/etc/xapi.d/plugins/pluginlib_nova.py
@@ -28,6 +28,7 @@ import re
 import time
 import XenAPI
 
+import XenAPI
 
 ##### Logging setup