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path: root/tests/generator/base.py
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#
# Blackbox tests of netplan generate that verify that the generated
# configuration files look as expected. These are run during "make check" and
# don't touch the system configuration at all.
#
# Copyright (C) 2016-2021 Canonical, Ltd.
# Author: Martin Pitt <martin.pitt@ubuntu.com>
# Author: Lukas Märdian <slyon@ubuntu.com>
#
# 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; version 3.
#
# 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/>.

import os
import random
import glob
import stat
import string
import tempfile
import subprocess
import unittest
import ctypes
import ctypes.util
import yaml
import difflib

exe_generate = os.environ.get('NETPLAN_GENERATE_PATH',
                              os.path.join(os.path.dirname(os.path.dirname(
                                           os.path.dirname(os.path.abspath(__file__)))), 'generate'))

# make sure we point to libnetplan properly.
os.environ.update({'LD_LIBRARY_PATH': '.:{}'.format(os.environ.get('LD_LIBRARY_PATH'))})

# make sure we fail on criticals
os.environ['G_DEBUG'] = 'fatal-criticals'

lib = ctypes.CDLL(ctypes.util.find_library('netplan'))

# common patterns for expected output
ND_EMPTY = '[Match]\nName=%s\n\n[Network]\nLinkLocalAddressing=%s\nConfigureWithoutCarrier=yes\n'
ND_WITHIP = '[Match]\nName=%s\n\n[Network]\nLinkLocalAddressing=ipv6\nAddress=%s\nConfigureWithoutCarrier=yes\n'
ND_WIFI_DHCP4 = '[Match]\nName=%s\n\n[Network]\nDHCP=ipv4\nLinkLocalAddressing=ipv6\n\n[DHCP]\nRouteMetric=600\nUseMTU=true\n'
ND_DHCP = '[Match]\nName=%s\n\n[Network]\nDHCP=%s\nLinkLocalAddressing=ipv6%s\n\n[DHCP]\nRouteMetric=100\nUseMTU=%s\n'
ND_DHCP4 = ND_DHCP % ('%s', 'ipv4', '', 'true')
ND_DHCP4_NOMTU = ND_DHCP % ('%s', 'ipv4', '', 'false')
ND_DHCP6 = ND_DHCP % ('%s', 'ipv6', '', 'true')
ND_DHCP6_NOMTU = ND_DHCP % ('%s', 'ipv6', '', 'false')
ND_DHCP6_WOCARRIER = ND_DHCP % ('%s', 'ipv6', '\nConfigureWithoutCarrier=yes', 'true')
ND_DHCPYES = ND_DHCP % ('%s', 'yes', '', 'true')
ND_DHCPYES_NOMTU = ND_DHCP % ('%s', 'yes', '', 'false')
_OVS_BASE = '[Unit]\nDescription=OpenVSwitch configuration for %(iface)s\nDefaultDependencies=no\n\
Wants=ovsdb-server.service\nAfter=ovsdb-server.service\n'
OVS_PHYSICAL = _OVS_BASE + 'Requires=sys-subsystem-net-devices-%(iface)s.device\nAfter=sys-subsystem-net-devices-%(iface)s\
.device\nAfter=netplan-ovs-cleanup.service\nBefore=network.target\nWants=network.target\n%(extra)s'
OVS_VIRTUAL = _OVS_BASE + 'After=netplan-ovs-cleanup.service\nBefore=network.target\nWants=network.target\n%(extra)s'
OVS_BR_DEFAULT = 'ExecStart=/usr/bin/ovs-vsctl set Bridge %(iface)s external-ids:netplan=true\nExecStart=/usr/bin/ovs-vsctl \
set-fail-mode %(iface)s standalone\nExecStart=/usr/bin/ovs-vsctl set Bridge %(iface)s external-ids:netplan/global/set-fail-mode=\
standalone\nExecStart=/usr/bin/ovs-vsctl set Bridge %(iface)s mcast_snooping_enable=false\nExecStart=/usr/bin/ovs-vsctl set \
Bridge %(iface)s external-ids:netplan/mcast_snooping_enable=false\nExecStart=/usr/bin/ovs-vsctl set Bridge %(iface)s \
rstp_enable=false\nExecStart=/usr/bin/ovs-vsctl set Bridge %(iface)s external-ids:netplan/rstp_enable=false\n'
OVS_BR_EMPTY = _OVS_BASE + 'After=netplan-ovs-cleanup.service\nBefore=network.target\nWants=network.target\n\n[Service]\n\
Type=oneshot\nTimeoutStartSec=10s\nExecStart=/usr/bin/ovs-vsctl --may-exist add-br %(iface)s\n' + OVS_BR_DEFAULT
OVS_CLEANUP = _OVS_BASE + 'ConditionFileIsExecutable=/usr/bin/ovs-vsctl\nBefore=network.target\nWants=network.target\n\n\
[Service]\nType=oneshot\nTimeoutStartSec=10s\nExecStart=/usr/sbin/netplan apply --only-ovs-cleanup\n'
UDEV_MAC_RULE = 'SUBSYSTEM=="net", ACTION=="add", DRIVERS=="%s", ATTR{address}=="%s", NAME="%s"\n'
UDEV_NO_MAC_RULE = 'SUBSYSTEM=="net", ACTION=="add", DRIVERS=="%s", NAME="%s"\n'
UDEV_SRIOV_RULE = 'ACTION=="add", SUBSYSTEM=="net", ATTRS{sriov_totalvfs}=="?*", RUN+="/usr/sbin/netplan apply --sriov-only"\n'
ND_WITHIPGW = '[Match]\nName=%s\n\n[Network]\nLinkLocalAddressing=ipv6\nAddress=%s\nAddress=%s\nGateway=%s\n\
ConfigureWithoutCarrier=yes\n'
NM_WG = '[connection]\nid=netplan-wg0\ntype=wireguard\ninterface-name=wg0\n\n[wireguard]\nprivate-key=%s\nlisten-port=%s\n%s\
\n\n[ipv4]\nmethod=manual\naddress1=15.15.15.15/24\ngateway=20.20.20.21\n\n[ipv6]\nmethod=manual\naddress1=\
2001:de:ad:be:ef:ca:fe:1/128\nip6-privacy=0\n'
ND_WG = '[NetDev]\nName=wg0\nKind=wireguard\n\n[WireGuard]\nPrivateKey%s\nListenPort=%s\n%s\n'
ND_VLAN = '[NetDev]\nName=%s\nKind=vlan\n\n[VLAN]\nId=%d\n'
ND_VXLAN = '[NetDev]\nName=%s\nKind=vxlan\n\n[VXLAN]\nVNI=%d\n'
ND_VRF = '[NetDev]\nName=%s\nKind=vrf\n\n[VRF]\nTable=%d\n'
SD_WPA = '''[Unit]
Description=WPA supplicant for netplan %(iface)s
DefaultDependencies=no
Requires=sys-subsystem-net-devices-%(iface)s.device
After=sys-subsystem-net-devices-%(iface)s.device
Before=network.target
Wants=network.target

[Service]
Type=simple
ExecStart=/sbin/wpa_supplicant -c /run/netplan/wpa-%(iface)s.conf -i%(iface)s -D%(drivers)s
'''
NM_MANAGED = 'SUBSYSTEM=="net", ACTION=="add|change|move", ENV{ID_NET_NAME}=="%s", ENV{NM_UNMANAGED}="0"\n'
NM_UNMANAGED = 'SUBSYSTEM=="net", ACTION=="add|change|move", ENV{ID_NET_NAME}=="%s", ENV{NM_UNMANAGED}="1"\n'
NM_MANAGED_MAC = 'SUBSYSTEM=="net", ACTION=="add|change|move", ATTR{address}=="%s", ENV{NM_UNMANAGED}="0"\n'
NM_UNMANAGED_MAC = 'SUBSYSTEM=="net", ACTION=="add|change|move", ATTR{address}=="%s", ENV{NM_UNMANAGED}="1"\n'
NM_MANAGED_DRIVER = 'SUBSYSTEM=="net", ACTION=="add|change|move", ENV{ID_NET_DRIVER}=="%s", ENV{NM_UNMANAGED}="0"\n'
NM_UNMANAGED_DRIVER = 'SUBSYSTEM=="net", ACTION=="add|change|move", ENV{ID_NET_DRIVER}=="%s", ENV{NM_UNMANAGED}="1"\n'


class NetplanV2Normalizer():

    def __init__(self):
        self.YAML_FALSE = ['n', 'no', 'off', 'false']
        self.YAML_TRUE = ['y', 'yes', 'on', 'true']
        self.DEFAULT_STANZAS = [
            'dhcp4-overrides: {}',  # 2nd level default (containing defaults itself)
            'dhcp6-overrides: {}',  # 2nd level default (containing defaults itself)
            'hidden: false',  # access-point
            'on-link: false',  # route
            'stp: true',  # paramters
            'type: unicast',  # route
            'version: 2',  # global
        ]
        self.DEFAULT_NETDEF = {
            'dhcp4': self.YAML_FALSE,
            'dhcp6': self.YAML_FALSE,
            'dhcp-identifier': ['duid'],
            'hidden': self.YAML_FALSE,
        }
        self.DEFAULT_DHCP = {
            'send-hostname': self.YAML_TRUE,
            'use-dns': self.YAML_TRUE,
            'use-hostname': self.YAML_TRUE,
            'use-mtu': self.YAML_TRUE,
            'use-ntp': self.YAML_TRUE,
            'use-routes': self.YAML_TRUE,
        }

    def _clear_mapping_defaults(self, keys, defaults, data):
        potential_defaults = list(set(keys) & set(defaults.keys()))
        for k in potential_defaults:
            if any(map(str(data[k]).lower().__eq__, defaults[k])):
                del data[k]

    def normalize_yaml_line(self, line):
        '''Process formatted YAML line by line (one setting/key per line)

        Deleting default values and re-writing to default wording
        '''
        kv = line.replace('"', '').replace('\'', '').split(':', 1)
        if len(kv) != 2 or kv[1].isspace() or kv[1] == '':
            return line  # no normalization needed; no value given

        # normalize key
        key = kv[0]
        if 'gratuitious-arp' in key:  # historically supported typo
            kv[0] = key.replace('gratuitious-arp', 'gratuitous-arp')

        # normalize value
        val = kv[1].strip()
        if val in self.YAML_FALSE:
            kv[1] = 'false'
        elif val in self.YAML_TRUE:
            kv[1] = 'true'
        elif val == '5G':
            kv[1] = '5GHz'
        elif val == '2.4G':
            kv[1] = '2.4GHz'
        else:  # no normalization needed or known
            kv[1] = val

        return ': '.join(kv)

    def normalize_yaml_tree(self, data, full_key=''):
        '''Walk the YAML dict/tree @data and sort its sequences in place

        Keeping track of the @full_key (path), e.g.: "network:ethernets:eth0:dhcp4"
        And normalizing certain netplan special cases
        '''
        if isinstance(data, list):
            scalars_only = not any(list(map(lambda elem: (isinstance(elem, dict) or isinstance(elem, list)), data)))
            # sort sequence alphabetically
            if scalars_only:
                data.sort()
                # remove duplicates (if needed)
                unique = set(data)
                if len(data) > len(unique):
                    rm_idx = set()
                    last_idx = 0
                    for elem in unique:
                        if data.count(elem) > 1:
                            idx = data.index(elem, last_idx)
                            rm_idx.add(idx)
                            last_idx = idx
                    for idx in rm_idx:
                        del data[idx]
        elif isinstance(data, dict):
            keys = data.keys()
            # expand special short forms
            if 'password' in keys and ':auth' not in full_key:
                data['auth'] = {'key-management': 'psk', 'password': data['password']}
                del data['password']
            if 'auth' in keys and data['auth'] == {}:
                data['auth'] = {'key-management': 'none'}
            # remove default stanza ("link-local: [ ipv6 ]"")
            if 'link-local' in keys and data['link-local'] == ['ipv6']:
                del data['link-local']
            # remove default stanza ("wakeonwlan: [ default ]")
            if 'wakeonwlan' in keys and data['wakeonwlan'] == ['default']:
                del data['wakeonwlan']
            # remove explicit openvswitch stanzas, they might not always be
            # defined in the original YAML (due to being implicit)
            if ('openvswitch' in keys and data['openvswitch'] == {} and
                    any(map(full_key.__contains__, [':bonds:', ':bridges:', ':vlans:']))):
                del data['openvswitch']
            # remove default empty bond-parameters, those are not rendered by the YAML generator
            if 'parameters' in keys and data['parameters'] == {} and ':bonds:' in full_key:
                del data['parameters']
            # remove default mode=infrastructore from wifi APs, keeping the SSID
            if 'mode' in keys and ':wifis:' in full_key and 'infrastructure' in data['mode']:
                del data['mode']
            # ignore renderer: on other than global levels for now, as that
            # information is currently not stored in the netdef data structure
            if ('renderer' in keys and len(full_key.split(':')) > 1 and
                    data['renderer'] in ['networkd', 'NetworkManager']):
                del data['renderer']
            # remove default values from the dhcp4/6-overrides mappings
            if full_key.endswith(':dhcp4-overrides') or full_key.endswith(':dhcp6-overrides'):
                self._clear_mapping_defaults(keys, self.DEFAULT_DHCP, data)
            # remove default values from netdef/interface mappings
            if len(full_key.split(':')) == 3:  # netdef level
                self._clear_mapping_defaults(keys, self.DEFAULT_NETDEF, data)

            # continue to walk the dict
            for key in data.keys():
                full_key_next = ':'.join([str(full_key), str(key)]) if full_key != '' else key
                self.normalize_yaml_tree(data[key], full_key_next)

    def normalize_yaml(self, yaml_dict):
        # 1st pass: normalize the YAML tree in place, sorting and removing some values
        self.normalize_yaml_tree(yaml_dict)
        # 2nd pass: sort the mapping keys and output a formatted yaml (one key per line)
        formatted_yaml = yaml.dump(yaml_dict, sort_keys=True)
        # 3rd pass: normalize the wording of certain keys/values per line
        #           and remove any line, containg only default values
        output = []
        for line in formatted_yaml.splitlines():
            line = self.normalize_yaml_line(line)
            if line.strip() in self.DEFAULT_STANZAS:
                continue
            output.append(line)
        return output


class TestBase(unittest.TestCase):

    def setUp(self):
        self.workdir = tempfile.TemporaryDirectory()
        self.confdir = os.path.join(self.workdir.name, 'etc', 'netplan')
        self.nm_enable_all_conf = os.path.join(
            self.workdir.name, 'run', 'NetworkManager', 'conf.d', '10-globally-managed-devices.conf')
        self.maxDiff = None

    def validate_generated_yaml(self, yaml_input):
        '''Validate a list of YAML input files one by one.

        Go through the list @yaml_input one by one, parse the YAML and
        re-generate the YAML output. Afterwards, normalize and compare the
        original (and normalized) input with the generated (and normalized)
        output.
        '''
        output = '_generated_test_output.yaml'
        output_path = os.path.join(self.confdir, output)

        for input in yaml_input:
            lib.netplan_clear_netdefs()  # clear previous netdefs
            lib.netplan_parse_yaml(input.encode(), None)
            lib.write_netplan_conf_full(output.encode(), self.workdir.name.encode())

            input_yaml = None
            output_yaml = None

            # Read input YAML file, as defined by the self.generate('...') method
            with open(input, 'r') as orig:
                input_yaml = yaml.safe_load(orig.read())
                # Consider 'network: {}' and 'network: {version: 2}' to be empty
                if input_yaml is None or input_yaml == {'network': {}} or input_yaml == {'network': {'version': 2}}:
                    input_yaml = yaml.safe_load('')

            # Read output of the YAML generator (if any)
            if os.path.isfile(output_path):
                with open(output_path, 'r') as generated:
                    output_yaml = yaml.safe_load(generated.read())
            else:
                output_yaml = yaml.safe_load('')

            # Normalize input and output YAML
            netplan_normalizer = NetplanV2Normalizer()
            input_lines = netplan_normalizer.normalize_yaml(input_yaml)
            output_lines = netplan_normalizer.normalize_yaml(output_yaml)

            # Check if (normalized) input and (normalized) output are equal
            yaml_files_differ = len(input_lines) != len(output_lines)
            if not yaml_files_differ:  # pragma: no cover (only execited in error case)
                for i in range(len(input_lines)):
                    if input_lines[i] != output_lines[i]:
                        yaml_files_differ = True
                        break
            if yaml_files_differ:  # pragma: no cover (only execited in error case)
                fromfile = 'original (%s)' % input
                for line in difflib.unified_diff(input_lines, output_lines, fromfile, tofile='generated', lineterm=''):
                    print(line, flush=True)
                self.fail('Re-generated YAML file does not match (adopt netplan.c YAML generator?)')

            # Cleanup the generated file and data structures
            lib.netplan_clear_netdefs()
            if os.path.isfile(output_path):
                os.remove(output_path)

    def generate(self, yaml, expect_fail=False, extra_args=[], confs=None, skip_generated_yaml_validation=False):
        '''Call generate with given YAML string as configuration

        Return stderr output.
        '''
        yaml_input = []
        conf = os.path.join(self.confdir, 'a.yaml')
        os.makedirs(os.path.dirname(conf), exist_ok=True)
        if yaml is not None:
            with open(conf, 'w') as f:
                f.write(yaml)
            yaml_input.append(conf)
        if confs:
            for f, contents in confs.items():
                path = os.path.join(self.confdir, f + '.yaml')
                with open(path, 'w') as f:
                    f.write(contents)
                yaml_input.append(path)

        argv = [exe_generate, '--root-dir', self.workdir.name] + extra_args
        if 'TEST_SHELL' in os.environ:  # pragma nocover
            print('Test is about to run:\n%s' % ' '.join(argv))
            subprocess.call(['bash', '-i'], cwd=self.workdir.name)

        p = subprocess.Popen(argv, stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE, universal_newlines=True)
        (out, err) = p.communicate()
        if expect_fail:
            self.assertGreater(p.returncode, 0)
        else:
            self.assertEqual(p.returncode, 0, err)
        self.assertEqual(out, '')
        if not expect_fail and not skip_generated_yaml_validation:
            yaml_input = list(set(yaml_input + extra_args))
            yaml_input.sort()
            self.validate_generated_yaml(yaml_input)
        return err

    def eth_name(self):
        """Return a link name.

        Use when you need a link name for a test but don't want to
        encode a made up name in the test.
        """
        return 'eth' + ''.join(random.sample(string.ascii_letters + string.digits, k=4))

    def assert_networkd(self, file_contents_map):
        networkd_dir = os.path.join(self.workdir.name, 'run', 'systemd', 'network')
        if not file_contents_map:
            self.assertFalse(os.path.exists(networkd_dir))
            return

        self.assertEqual(set(os.listdir(self.workdir.name)) - {'lib'}, {'etc', 'run'})
        self.assertEqual(set(os.listdir(networkd_dir)),
                         {'10-netplan-' + f for f in file_contents_map})
        for fname, contents in file_contents_map.items():
            with open(os.path.join(networkd_dir, '10-netplan-' + fname)) as f:
                self.assertEqual(f.read(), contents)

    def assert_additional_udev(self, file_contents_map):
        udev_dir = os.path.join(self.workdir.name, 'run', 'udev', 'rules.d')
        for fname, contents in file_contents_map.items():
            with open(os.path.join(udev_dir, fname)) as f:
                self.assertEqual(f.read(), contents)

    def assert_networkd_udev(self, file_contents_map):
        udev_dir = os.path.join(self.workdir.name, 'run', 'udev', 'rules.d')
        if not file_contents_map:
            # it can either not exist, or can only contain 90-netplan.rules
            self.assertTrue((not os.path.exists(udev_dir)) or
                            (os.listdir(udev_dir) == ['90-netplan.rules']))
            return

        self.assertEqual(set(os.listdir(udev_dir)) - set(['90-netplan.rules']),
                         {'99-netplan-' + f for f in file_contents_map})
        for fname, contents in file_contents_map.items():
            with open(os.path.join(udev_dir, '99-netplan-' + fname)) as f:
                self.assertEqual(f.read(), contents)

    def get_network_config_for_link(self, link_name):
        """Return the content of the .network file for `link_name`."""
        networkd_dir = os.path.join(self.workdir.name, 'run', 'systemd', 'network')
        with open(os.path.join(networkd_dir, '10-netplan-{}.network'.format(link_name))) as f:
            return f.read()

    def get_optional_addresses(self, eth_name):
        config = self.get_network_config_for_link(eth_name)
        r = set()
        prefix = "OptionalAddresses="
        for line in config.splitlines():
            if line.startswith(prefix):
                r.add(line[len(prefix):])
        return r

    def assert_nm(self, connections_map=None, conf=None):
        # check config
        conf_path = os.path.join(self.workdir.name, 'run', 'NetworkManager', 'conf.d', 'netplan.conf')
        if conf:
            with open(conf_path) as f:
                self.assertEqual(f.read(), conf)
        else:
            if os.path.exists(conf_path):
                with open(conf_path) as f:  # pragma: nocover
                    self.fail('unexpected %s:\n%s' % (conf_path, f.read()))

        # check connections
        con_dir = os.path.join(self.workdir.name, 'run', 'NetworkManager', 'system-connections')
        if connections_map:
            self.assertEqual(set(os.listdir(con_dir)),
                             set(['netplan-' + n.split('.nmconnection')[0] + '.nmconnection' for n in connections_map]))
            for fname, contents in connections_map.items():
                extension = ''
                if '.nmconnection' not in fname:
                    extension = '.nmconnection'
                with open(os.path.join(con_dir, 'netplan-' + fname + extension)) as f:
                    self.assertEqual(f.read(), contents)
                    # NM connection files might contain secrets
                    self.assertEqual(stat.S_IMODE(os.fstat(f.fileno()).st_mode), 0o600)
        else:
            if os.path.exists(con_dir):
                self.assertEqual(os.listdir(con_dir), [])

    def assert_nm_udev(self, contents):
        rule_path = os.path.join(self.workdir.name, 'run/udev/rules.d/90-netplan.rules')
        if contents is None:
            self.assertFalse(os.path.exists(rule_path))
            return
        with open(rule_path) as f:
            lines = []
            for line in f.readlines():
                # ignore any comment in udev rules.d file
                if not line.startswith('#'):
                    lines.append(line)
            self.assertEqual(''.join(lines), contents)

    def assert_ovs(self, file_contents_map):
        systemd_dir = os.path.join(self.workdir.name, 'run', 'systemd', 'system')
        if not file_contents_map:
            # in this case we assume no OVS configuration should be present
            self.assertFalse(glob.glob(os.path.join(systemd_dir, '*netplan-ovs-*.service')))
            return

        self.assertEqual(set(os.listdir(self.workdir.name)) - {'lib'}, {'etc', 'run'})
        ovs_systemd_dir = set(os.listdir(systemd_dir))
        ovs_systemd_dir.remove('systemd-networkd.service.wants')
        self.assertEqual(ovs_systemd_dir, {'netplan-ovs-' + f for f in file_contents_map})
        for fname, contents in file_contents_map.items():
            fname = 'netplan-ovs-' + fname
            with open(os.path.join(systemd_dir, fname)) as f:
                self.assertEqual(f.read(), contents)
            if fname.endswith('.service'):
                link_path = os.path.join(
                    systemd_dir, 'systemd-networkd.service.wants', fname)
                self.assertTrue(os.path.islink(link_path))
                link_target = os.readlink(link_path)
                self.assertEqual(link_target,
                                 os.path.join(
                                    '/', 'run', 'systemd', 'system', fname))

    def assert_sriov(self, file_contents_map):
        systemd_dir = os.path.join(self.workdir.name, 'run', 'systemd', 'system')
        sriov_systemd_dir = glob.glob(os.path.join(systemd_dir, '*netplan-sriov-*.service'))
        self.assertEqual(set(os.path.basename(file) for file in sriov_systemd_dir),
                         {'netplan-sriov-' + f for f in file_contents_map})
        self.assertEqual(set(os.listdir(self.workdir.name)) - {'lib'}, {'etc', 'run'})