neutron-fwaas/neutron_fwaas/services/firewall/service_drivers/agents/drivers/linux/l2/openvswitch_firewall/rules.py

209 lines
7.5 KiB
Python

# Copyright 2015 Red Hat, Inc.
# All Rights Reserved.
#
# 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.
import netaddr
from neutron.common import utils
from neutron.plugins.ml2.drivers.openvswitch.agent.common import constants \
as ovs_consts
from neutron_lib import constants as n_consts
from oslo_log import log as logging
from neutron_fwaas.services.firewall.service_drivers.agents.drivers.linux.l2.\
openvswitch_firewall import constants as fwaas_ovs_consts
LOG = logging.getLogger(__name__)
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver, differs in
# constants
CT_STATES = [
fwaas_ovs_consts.OF_STATE_ESTABLISHED_NOT_REPLY,
fwaas_ovs_consts.OF_STATE_NEW_NOT_ESTABLISHED]
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
FLOW_FIELD_FOR_IPVER_AND_DIRECTION = {
(n_consts.IP_VERSION_4, n_consts.EGRESS_DIRECTION): 'nw_dst',
(n_consts.IP_VERSION_6, n_consts.EGRESS_DIRECTION): 'ipv6_dst',
(n_consts.IP_VERSION_4, n_consts.INGRESS_DIRECTION): 'nw_src',
(n_consts.IP_VERSION_6, n_consts.INGRESS_DIRECTION): 'ipv6_src',
}
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
FORBIDDEN_PREFIXES = (n_consts.IPv4_ANY, n_consts.IPv6_ANY)
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
def is_valid_prefix(ip_prefix):
# IPv6 have multiple ways how to describe ::/0 network, converting to
# IPNetwork and back to string unifies it
return (ip_prefix and
str(netaddr.IPNetwork(ip_prefix)) not in FORBIDDEN_PREFIXES)
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
def create_flows_from_rule_and_port(rule, port):
ethertype = rule['ethertype']
direction = rule['direction']
dst_ip_prefix = rule.get('dest_ip_prefix')
src_ip_prefix = rule.get('source_ip_prefix')
offset = int(rule.get('offset', 0))
flow_template = {
'priority': 70 + offset,
'dl_type': fwaas_ovs_consts.ethertype_to_dl_type_map[ethertype],
'reg_port': port.ofport,
}
if is_valid_prefix(dst_ip_prefix):
flow_template[FLOW_FIELD_FOR_IPVER_AND_DIRECTION[(
utils.get_ip_version(dst_ip_prefix), n_consts.EGRESS_DIRECTION)]
] = dst_ip_prefix
if is_valid_prefix(src_ip_prefix):
flow_template[FLOW_FIELD_FOR_IPVER_AND_DIRECTION[(
utils.get_ip_version(src_ip_prefix), n_consts.INGRESS_DIRECTION)]
] = src_ip_prefix
flows = create_protocol_flows(direction, flow_template, port, rule)
return flows
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver, differs in
# constants
def populate_flow_common(direction, flow_template, port):
"""Initialize common flow fields."""
if direction == n_consts.INGRESS_DIRECTION:
flow_template['table'] = fwaas_ovs_consts.FW_RULES_INGRESS_TABLE
flow_template['actions'] = "output:{:d}".format(port.ofport)
elif direction == n_consts.EGRESS_DIRECTION:
flow_template['table'] = fwaas_ovs_consts.FW_RULES_EGRESS_TABLE
# Traffic can be both ingress and egress, check that no ingress rules
# should be applied
flow_template['actions'] = 'resubmit(,{:d})'.format(
fwaas_ovs_consts.FW_ACCEPT_OR_INGRESS_TABLE)
return flow_template
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
def create_protocol_flows(direction, flow_template, port, rule):
flow_template = populate_flow_common(direction,
flow_template.copy(),
port)
protocol = rule.get('protocol')
if protocol is not None:
flow_template['nw_proto'] = protocol
if protocol in [n_consts.PROTO_NUM_ICMP, n_consts.PROTO_NUM_IPV6_ICMP]:
flows = create_icmp_flows(flow_template, rule)
else:
flows = create_port_range_flows(flow_template, rule)
return flows or [flow_template]
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver, differs only in
# constant
def create_port_range_flows(flow_template, rule):
protocol = fwaas_ovs_consts.REVERSE_IP_PROTOCOL_MAP_WITH_PORTS.get(
rule.get('protocol'))
if protocol is None:
return []
flows = []
src_port_match = '{:s}_src'.format(protocol)
src_port_min = rule.get('source_port_range_min')
src_port_max = rule.get('source_port_range_max')
dst_port_match = '{:s}_dst'.format(protocol)
dst_port_min = rule.get('port_range_min')
dst_port_max = rule.get('port_range_max')
dst_port_range = []
if dst_port_min and dst_port_max:
dst_port_range = utils.port_rule_masking(dst_port_min, dst_port_max)
src_port_range = []
if src_port_min and src_port_max:
src_port_range = utils.port_rule_masking(src_port_min, src_port_max)
for port in src_port_range:
flow = flow_template.copy()
flow[src_port_match] = port
if dst_port_range:
for port in dst_port_range:
dst_flow = flow.copy()
dst_flow[dst_port_match] = port
flows.append(dst_flow)
else:
flows.append(flow)
else:
for port in dst_port_range:
flow = flow_template.copy()
flow[dst_port_match] = port
flows.append(flow)
return flows
# NOTE(ivasilevskaya) copy-paste from neutron ovsfw driver
def create_icmp_flows(flow_template, rule):
icmp_type = rule.get('port_range_min')
if icmp_type is None:
return
flow = flow_template.copy()
flow['icmp_type'] = icmp_type
icmp_code = rule.get('port_range_max')
if icmp_code is not None:
flow['icmp_code'] = icmp_code
return [flow]
def resubmit_to_sg(flow):
if flow['table'] == fwaas_ovs_consts.FW_RULES_EGRESS_TABLE:
flow['actions'] = 'resubmit(,{:d})'.format(
ovs_consts.RULES_EGRESS_TABLE)
if flow['table'] == fwaas_ovs_consts.FW_RULES_INGRESS_TABLE:
flow['actions'] = 'resubmit(,{:d})'.format(
ovs_consts.RULES_INGRESS_TABLE)
def create_accept_flows(flow, sg_enabled=False):
flow['ct_state'] = CT_STATES[0]
if sg_enabled:
resubmit_to_sg(flow)
result = [flow.copy()]
flow['ct_state'] = CT_STATES[1]
if sg_enabled:
resubmit_to_sg(flow)
elif flow['table'] == fwaas_ovs_consts.FW_RULES_INGRESS_TABLE:
flow['actions'] = (
'ct(commit,zone=NXM_NX_REG{:d}[0..15]),{:s},'
'resubmit(,{:d})'.format(
fwaas_ovs_consts.REG_NET, flow['actions'],
ovs_consts.ACCEPTED_INGRESS_TRAFFIC_TABLE)
)
result.append(flow)
return result
def create_drop_flows(flow):
if flow['table'] in [fwaas_ovs_consts.FW_RULES_INGRESS_TABLE,
fwaas_ovs_consts.FW_RULES_EGRESS_TABLE]:
flow['actions'] = 'resubmit(,%d)' % ovs_consts.DROPPED_TRAFFIC_TABLE
flow['ct_state'] = fwaas_ovs_consts.OF_STATE_NEW_NOT_ESTABLISHED
result = [flow.copy()]
flow['ct_state'] = fwaas_ovs_consts.OF_STATE_ESTABLISHED_NOT_REPLY
result.append(flow)
return result