Review adjustments.

cloudinit/config/cc_seed_random.py

@@ -0,0 +1,36 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2013 Yahoo! Inc.
+#
+#    Author: Joshua Harlow <harlowja@yahoo-inc.com>
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    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, see <http://www.gnu.org/licenses/>.
+
+from cloudinit.settings import PER_INSTANCE
+
+frequency = PER_INSTANCE
+
+
+def handle(name, cfg, cloud, log, _args):
+    random_seed = None
+    # Prefer metadata over cfg for random_seed
+    for src in (cloud.datasource.metadata, cfg):
+        if not src:
+            continue
+        tmp_random_seed = src.get('random_seed')
+        if tmp_random_seed and isinstance(tmp_random_seed, (str, basestring)):
+            random_seed = tmp_random_seed
+            break
+    if random_seed:
+        log.debug("%s: setting random seed", name)
+        cloud.distro.set_random_seed(random_seed)

cloudinit/distros/__init__.py

@@ -52,7 +52,7 @@ class Distro(object):
     ci_sudoers_fn = "/etc/sudoers.d/90-cloud-init-users"
     hostname_conf_fn = "/etc/hostname"
     tz_zone_dir = "/usr/share/zoneinfo"
-    random_seed_fn = None
+    random_seed_fn = '/dev/urandom'
 
     def __init__(self, name, cfg, paths):
         self._paths = paths
@@ -171,11 +171,13 @@ class Distro(object):
         return distros
 
     def set_random_seed(self, seed):
-        if not self.random_seed_fn:
+        if not self.random_seed_fn or not os.path.exists(self.random_seed_fn):
             raise IOError("No random seed filename provided for %s"
                           % (self.name))
+        if not seed:
+            raise IOError("Unable to set empty random seed")
         # Ensure we only write 512 bytes worth
-        util.write_file(self.random_seed_fn, seed[0:512], mode=0600)
+        util.append_file(self.random_seed_fn, seed[0:512])
 
     def update_hostname(self, hostname, fqdn, prev_hostname_fn):
         applying_hostname = hostname

cloudinit/distros/debian.py

@@ -44,7 +44,6 @@ class Distro(distros.Distro):
     network_conf_fn = "/etc/network/interfaces"
     tz_conf_fn = "/etc/timezone"
     tz_local_fn = "/etc/localtime"
-    random_seed_fn = "/var/lib/urandom/random-seed"
 
     def __init__(self, name, cfg, paths):
         distros.Distro.__init__(self, name, cfg, paths)

cloudinit/distros/rhel.py

@@ -49,7 +49,6 @@ class Distro(distros.Distro):
     network_script_tpl = '/etc/sysconfig/network-scripts/ifcfg-%s'
     resolve_conf_fn = "/etc/resolv.conf"
     tz_local_fn = "/etc/localtime"
-    random_seed_fn = "/var/lib/random-seed"
 
     def __init__(self, name, cfg, paths):
         distros.Distro.__init__(self, name, cfg, paths)

cloudinit/sources/DataSourceConfigDrive.py

@@ -59,13 +59,6 @@ class ConfigDriveHelper(object):
                 write_files(files)
             except IOError:
                 util.logexc(LOG, "Failed writing files")
-        random_seed = util.get_cfg_by_path(data, ('metadata', 'random_seed'))
-        if random_seed is not None:
-            LOG.debug("Writing random seed")
-            try:
-                self.distro.set_random_seed(random_seed)
-            except IOError:
-                util.logexc(LOG, "Failed writing random seed")
 
 
 class DataSourceConfigDrive(sources.DataSource):

config/cloud.cfg

@@ -24,6 +24,7 @@ preserve_hostname: false
 # The modules that run in the 'init' stage
 cloud_init_modules:
  - migrator
+ - seed_random
  - bootcmd
  - write-files
  - growpart