merge from trunk.net1

1 files changed, 121 insertions, 10 deletions

diff --git a/cloudinit/net/__init__.py b/cloudinit/net/__init__.py
index e2dcaee7..0560fa45 100644
--- a/cloudinit/net/__init__.py
+++ b/cloudinit/net/__init__.py
@@ -29,6 +29,7 @@ from . import network_state
 LOG = logging.getLogger(__name__)
 
 SYS_CLASS_NET = "/sys/class/net/"
+LINKS_FNAME_PREFIX = "etc/systemd/network/50-cloud-init-"
 
 NET_CONFIG_OPTIONS = [
     "address", "netmask", "broadcast", "network", "metric", "gateway",
@@ -46,6 +47,8 @@ NET_CONFIG_BRIDGE_OPTIONS = [
     "bridge_hello", "bridge_maxage", "bridge_maxwait", "bridge_stp",
     ]
 
+DEFAULT_PRIMARY_INTERFACE = 'eth0'
+
 
 def sys_dev_path(devname, path=""):
     return SYS_CLASS_NET + devname + "/" + path
@@ -510,18 +513,126 @@ def render_interfaces(network_state):
     return content
 
 
-def render_network_state(target, network_state):
-    eni = 'etc/network/interfaces'
-    netrules = 'etc/udev/rules.d/70-persistent-net.rules'
+def render_network_state(target, network_state, eni="etc/network/interfaces",
+                         links_prefix=LINKS_FNAME_PREFIX,
+                         netrules='etc/udev/rules.d/70-persistent-net.rules'):
 
-    eni = os.path.sep.join((target, eni,))
-    util.ensure_dir(os.path.dirname(eni))
-    with open(eni, 'w+') as f:
+    fpeni = os.path.sep.join((target, eni,))
+    util.ensure_dir(os.path.dirname(fpeni))
+    with open(fpeni, 'w+') as f:
         f.write(render_interfaces(network_state))
 
-    netrules = os.path.sep.join((target, netrules,))
-    util.ensure_dir(os.path.dirname(netrules))
-    with open(netrules, 'w+') as f:
-        f.write(render_persistent_net(network_state))
+    if netrules:
+        netrules = os.path.sep.join((target, netrules,))
+        util.ensure_dir(os.path.dirname(netrules))
+        with open(netrules, 'w+') as f:
+            f.write(render_persistent_net(network_state))
+
+    if links_prefix:
+        render_systemd_links(target, network_state, links_prefix)
+
+
+def render_systemd_links(target, network_state,
+                         links_prefix=LINKS_FNAME_PREFIX):
+    fp_prefix = os.path.sep.join((target, links_prefix))
+    for f in glob.glob(fp_prefix + "*"):
+        os.unlink(f)
+
+    interfaces = network_state.get('interfaces')
+    for iface in interfaces.values():
+        if (iface['type'] == 'physical' and 'name' in iface and
+                'mac_address' in iface):
+            fname = fp_prefix + iface['name'] + ".link"
+            with open(fname, "w") as fp:
+                fp.write("\n".join([
+                    "[Match]",
+                    "MACAddress=" + iface['mac_address'],
+                    "",
+                    "[Link]",
+                    "Name=" + iface['name'],
+                    ""
+                ]))
+
+
+def is_disabled_cfg(cfg):
+    if not cfg or not isinstance(cfg, dict):
+        return False
+    return cfg.get('config') == "disabled"
+
+
+def generate_fallback_config():
+    """Determine which attached net dev is most likely to have a connection and
+       generate network state to run dhcp on that interface"""
+    # by default use eth0 as primary interface
+    nconf = {'config': [], 'version': 1}
+
+    # get list of interfaces that could have connections
+    invalid_interfaces = set(['lo'])
+    potential_interfaces = set(os.listdir(SYS_CLASS_NET))
+    potential_interfaces = potential_interfaces.difference(invalid_interfaces)
+    # sort into interfaces with carrier, interfaces which could have carrier,
+    # and ignore interfaces that are definitely disconnected
+    connected = []
+    possibly_connected = []
+    for interface in potential_interfaces:
+        try:
+            sysfs_carrier = os.path.join(SYS_CLASS_NET, interface, 'carrier')
+            carrier = int(util.load_file(sysfs_carrier).strip())
+            if carrier:
+                connected.append(interface)
+                continue
+        except OSError:
+            pass
+        # check if nic is dormant or down, as this may make a nick appear to
+        # not have a carrier even though it could acquire one when brought
+        # online by dhclient
+        try:
+            sysfs_dormant = os.path.join(SYS_CLASS_NET, interface, 'dormant')
+            dormant = int(util.load_file(sysfs_dormant).strip())
+            if dormant:
+                possibly_connected.append(interface)
+                continue
+        except OSError:
+            pass
+        try:
+            sysfs_operstate = os.path.join(SYS_CLASS_NET, interface,
+                                           'operstate')
+            operstate = util.load_file(sysfs_operstate).strip()
+            if operstate in ['dormant', 'down', 'lowerlayerdown', 'unknown']:
+                possibly_connected.append(interface)
+                continue
+        except OSError:
+            pass
+
+    # don't bother with interfaces that might not be connected if there are
+    # some that definitely are
+    if connected:
+        potential_interfaces = connected
+    else:
+        potential_interfaces = possibly_connected
+    # if there are no interfaces, give up
+    if not potential_interfaces:
+        return
+    # if eth0 exists use it above anything else, otherwise get the interface
+    # that looks 'first'
+    if DEFAULT_PRIMARY_INTERFACE in potential_interfaces:
+        name = DEFAULT_PRIMARY_INTERFACE
+    else:
+        name = sorted(potential_interfaces)[0]
+
+    sysfs_mac = os.path.join(SYS_CLASS_NET, name, 'address')
+    mac = util.load_file(sysfs_mac).strip()
+    target_name = name
+
+    nconf['config'].append(
+        {'type': 'physical', 'name': target_name,
+         'mac_address': mac, 'subnets': [{'type': 'dhcp4'}]})
+    return nconf
+
+
+def read_kernel_cmdline_config():
+    # FIXME: add implementation here
+    return None
+
 
 # vi: ts=4 expandtab syntax=python