Rename to net/renderers and klibc -> cmdline.py

1 files changed, 191 insertions, 0 deletions

diff --git a/cloudinit/net/cmdline.py b/cloudinit/net/cmdline.py
new file mode 100644
index 00000000..958c264b
--- /dev/null
+++ b/cloudinit/net/cmdline.py
@@ -0,0 +1,191 @@
+#   Copyright (C) 2013-2014 Canonical Ltd.
+#
+#   Author: Scott Moser <scott.moser@canonical.com>
+#   Author: Blake Rouse <blake.rouse@canonical.com>
+#
+#   Curtin is free software: you can redistribute it and/or modify it under
+#   the terms of the GNU Affero General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   Curtin 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 Affero General Public License for
+#   more details.
+#
+#   You should have received a copy of the GNU Affero General Public License
+#   along with Curtin.  If not, see <http://www.gnu.org/licenses/>.
+
+import base64
+import glob
+import gzip
+import io
+import shlex
+
+from cloudinit.net import get_devicelist
+from cloudinit.net import sys_netdev_info
+
+from cloudinit import util
+
+
+def _load_shell_content(content, add_empty=False, empty_val=None):
+    """Given shell like syntax (key=value\nkey2=value2\n) in content
+       return the data in dictionary form.  If 'add_empty' is True
+       then add entries in to the returned dictionary for 'VAR='
+       variables.  Set their value to empty_val."""
+    data = {}
+    for line in shlex.split(content):
+        key, value = line.split("=", 1)
+        if not value:
+            value = empty_val
+        if add_empty or value:
+            data[key] = value
+
+    return data
+
+
+def _klibc_to_config_entry(content, mac_addrs=None):
+    """Convert a klibc writtent shell content file to a 'config' entry
+    When ip= is seen on the kernel command line in debian initramfs
+    and networking is brought up, ipconfig will populate
+    /run/net-<name>.cfg.
+
+    The files are shell style syntax, and examples are in the tests
+    provided here.  There is no good documentation on this unfortunately.
+
+    DEVICE=<name> is expected/required and PROTO should indicate if
+    this is 'static' or 'dhcp'.
+    """
+
+    if mac_addrs is None:
+        mac_addrs = {}
+
+    data = _load_shell_content(content)
+    try:
+        name = data['DEVICE']
+    except KeyError:
+        raise ValueError("no 'DEVICE' entry in data")
+
+    # ipconfig on precise does not write PROTO
+    proto = data.get('PROTO')
+    if not proto:
+        if data.get('filename'):
+            proto = 'dhcp'
+        else:
+            proto = 'static'
+
+    if proto not in ('static', 'dhcp'):
+        raise ValueError("Unexpected value for PROTO: %s" % proto)
+
+    iface = {
+        'type': 'physical',
+        'name': name,
+        'subnets': [],
+    }
+
+    if name in mac_addrs:
+        iface['mac_address'] = mac_addrs[name]
+
+    # originally believed there might be IPV6* values
+    for v, pre in (('ipv4', 'IPV4'),):
+        # if no IPV4ADDR or IPV6ADDR, then go on.
+        if pre + "ADDR" not in data:
+            continue
+        subnet = {'type': proto, 'control': 'manual'}
+
+        # these fields go right on the subnet
+        for key in ('NETMASK', 'BROADCAST', 'GATEWAY'):
+            if pre + key in data:
+                subnet[key.lower()] = data[pre + key]
+
+        dns = []
+        # handle IPV4DNS0 or IPV6DNS0
+        for nskey in ('DNS0', 'DNS1'):
+            ns = data.get(pre + nskey)
+            # verify it has something other than 0.0.0.0 (or ipv6)
+            if ns and len(ns.strip(":.0")):
+                dns.append(data[pre + nskey])
+        if dns:
+            subnet['dns_nameservers'] = dns
+            # add search to both ipv4 and ipv6, as it has no namespace
+            search = data.get('DOMAINSEARCH')
+            if search:
+                if ',' in search:
+                    subnet['dns_search'] = search.split(",")
+                else:
+                    subnet['dns_search'] = search.split()
+
+        iface['subnets'].append(subnet)
+
+    return name, iface
+
+
+def config_from_klibc_net_cfg(files=None, mac_addrs=None):
+    if files is None:
+        files = glob.glob('/run/net*.conf')
+
+    entries = []
+    names = {}
+    for cfg_file in files:
+        name, entry = _klibc_to_config_entry(util.load_file(cfg_file),
+                                             mac_addrs=mac_addrs)
+        if name in names:
+            raise ValueError(
+                "device '%s' defined multiple times: %s and %s" % (
+                    name, names[name], cfg_file))
+
+        names[name] = cfg_file
+        entries.append(entry)
+    return {'config': entries, 'version': 1}
+
+
+def _decomp_gzip(blob, strict=True):
+    # decompress blob. raise exception if not compressed unless strict=False.
+    with io.BytesIO(blob) as iobuf:
+        gzfp = None
+        try:
+            gzfp = gzip.GzipFile(mode="rb", fileobj=iobuf)
+            return gzfp.read()
+        except IOError:
+            if strict:
+                raise
+            return blob
+        finally:
+            if gzfp:
+                gzfp.close()
+
+
+def _b64dgz(b64str, gzipped="try"):
+    # decode a base64 string.  If gzipped is true, transparently uncompresss
+    # if gzipped is 'try', then try gunzip, returning the original on fail.
+    try:
+        blob = base64.b64decode(b64str)
+    except TypeError:
+        raise ValueError("Invalid base64 text: %s" % b64str)
+
+    if not gzipped:
+        return blob
+
+    return _decomp_gzip(blob, strict=gzipped != "try")
+
+
+def read_kernel_cmdline_config(files=None, mac_addrs=None, cmdline=None):
+    if cmdline is None:
+        cmdline = util.get_cmdline()
+
+    if 'network-config=' in cmdline:
+        data64 = None
+        for tok in cmdline.split():
+            if tok.startswith("network-config="):
+                data64 = tok.split("=", 1)[1]
+        if data64:
+            return util.load_yaml(_b64dgz(data64))
+
+    if 'ip=' not in cmdline:
+        return None
+
+    if mac_addrs is None:
+        mac_addrs = {k: sys_netdev_info(k, 'address')
+                     for k in get_devicelist()}
+
+    return config_from_klibc_net_cfg(files=files, mac_addrs=mac_addrs)