Edit File: zone.py
# -*- coding: utf-8 -*- # # Copyright (C) 2011-2016 Red Hat, Inc. # # Authors: # Thomas Woerner <twoerner@redhat.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; either version 2 of the License, or # (at your option) any later version. # # 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/>. # __all__ = [ "Zone", "zone_reader", "zone_writer" ] import xml.sax as sax import os import io import shutil from firewall import config from firewall.functions import checkIPnMask, checkIP6nMask, checkInterface, uniqify, max_zone_name_len, u2b_if_py2, check_mac from firewall.core.base import DEFAULT_ZONE_TARGET, ZONE_TARGETS from firewall.core.io.io_object import PY2, IO_Object, \ IO_Object_ContentHandler, IO_Object_XMLGenerator from firewall.core.io.policy import common_startElement, common_endElement, common_check_config, common_writer from firewall.core import rich from firewall.core.logger import log from firewall import errors from firewall.errors import FirewallError class Zone(IO_Object): """ Zone class """ IMPORT_EXPORT_STRUCTURE = ( ( "version", "" ), # s ( "short", "" ), # s ( "description", "" ), # s ( "UNUSED", False ), # b ( "target", "" ), # s ( "services", [ "", ], ), # as ( "ports", [ ( "", "" ), ], ), # a(ss) ( "icmp_blocks", [ "", ], ), # as ( "masquerade", False ), # b ( "forward_ports", [ ( "", "", "", "" ), ], ), # a(ssss) ( "interfaces", [ "" ] ), # as ( "sources", [ "" ] ), # as ( "rules_str", [ "" ] ), # as ( "protocols", [ "", ], ), # as ( "source_ports", [ ( "", "" ), ], ), # a(ss) ( "icmp_block_inversion", False ), # b ( "forward", False ), # b ) ADDITIONAL_ALNUM_CHARS = [ "_", "-", "/" ] PARSER_REQUIRED_ELEMENT_ATTRS = { "short": None, "description": None, "zone": None, "service": [ "name" ], "port": [ "port", "protocol" ], "icmp-block": [ "name" ], "icmp-type": [ "name" ], "forward": None, "forward-port": [ "port", "protocol" ], "interface": [ "name" ], "rule": None, "source": None, "destination": [ "address" ], "protocol": [ "value" ], "source-port": [ "port", "protocol" ], "log": None, "audit": None, "accept": None, "reject": None, "drop": None, "mark": [ "set" ], "limit": [ "value" ], "icmp-block-inversion": None, } PARSER_OPTIONAL_ELEMENT_ATTRS = { "zone": [ "name", "immutable", "target", "version" ], "masquerade": [ "enabled" ], "forward-port": [ "to-port", "to-addr" ], "rule": [ "family", "priority" ], "source": [ "address", "mac", "invert", "family", "ipset" ], "destination": [ "invert" ], "log": [ "prefix", "level" ], "reject": [ "type" ], } @staticmethod def index_of(element): for i, (el, dummy) in enumerate(Zone.IMPORT_EXPORT_STRUCTURE): if el == element: return i raise FirewallError(errors.UNKNOWN_ERROR, "index_of()") def __init__(self): super(Zone, self).__init__() self.version = "" self.short = "" self.description = "" self.UNUSED = False self.target = DEFAULT_ZONE_TARGET self.services = [ ] self.ports = [ ] self.protocols = [ ] self.icmp_blocks = [ ] self.forward = False self.masquerade = False self.forward_ports = [ ] self.source_ports = [ ] self.interfaces = [ ] self.sources = [ ] self.fw_config = None # to be able to check services and a icmp_blocks self.rules = [ ] self.rules_str = [ ] self.icmp_block_inversion = False self.combined = False self.applied = False def cleanup(self): self.version = "" self.short = "" self.description = "" self.UNUSED = False self.target = DEFAULT_ZONE_TARGET del self.services[:] del self.ports[:] del self.protocols[:] del self.icmp_blocks[:] self.forward = False self.masquerade = False del self.forward_ports[:] del self.source_ports[:] del self.interfaces[:] del self.sources[:] self.fw_config = None # to be able to check services and a icmp_blocks del self.rules[:] del self.rules_str[:] self.icmp_block_inversion = False self.combined = False self.applied = False def encode_strings(self): """ HACK. I haven't been able to make sax parser return strings encoded (because of python 2) instead of in unicode. Get rid of it once we throw out python 2 support.""" self.version = u2b_if_py2(self.version) self.short = u2b_if_py2(self.short) self.description = u2b_if_py2(self.description) self.target = u2b_if_py2(self.target) self.services = [u2b_if_py2(s) for s in self.services] self.ports = [(u2b_if_py2(po),u2b_if_py2(pr)) for (po,pr) in self.ports] self.protocols = [u2b_if_py2(pr) for pr in self.protocols] self.icmp_blocks = [u2b_if_py2(i) for i in self.icmp_blocks] self.forward_ports = [(u2b_if_py2(p1),u2b_if_py2(p2),u2b_if_py2(p3),u2b_if_py2(p4)) for (p1,p2,p3,p4) in self.forward_ports] self.source_ports = [(u2b_if_py2(po),u2b_if_py2(pr)) for (po,pr) in self.source_ports] self.interfaces = [u2b_if_py2(i) for i in self.interfaces] self.sources = [u2b_if_py2(s) for s in self.sources] self.rules = [u2b_if_py2(s) for s in self.rules] self.rules_str = [u2b_if_py2(s) for s in self.rules_str] def __setattr__(self, name, value): if name == "rules_str": self.rules = [rich.Rich_Rule(rule_str=s) for s in value] # must convert back to string to get the canonical string. super(Zone, self).__setattr__(name, [str(s) for s in self.rules]) else: super(Zone, self).__setattr__(name, value) def export_config_dict(self): conf = super(Zone, self).export_config_dict() del conf["UNUSED"] return conf def _check_config(self, config, item, all_config): common_check_config(self, config, item, all_config) if item == "target": if config not in ZONE_TARGETS: raise FirewallError(errors.INVALID_TARGET, config) elif item == "interfaces": for interface in config: if not checkInterface(interface): raise FirewallError(errors.INVALID_INTERFACE, interface) if self.fw_config: for zone in self.fw_config.get_zones(): if zone == self.name: continue if interface in self.fw_config.get_zone(zone).interfaces: raise FirewallError(errors.INVALID_INTERFACE, "interface '{}' already bound to zone '{}'".format(interface, zone)) elif item == "sources": for source in config: if not checkIPnMask(source) and not checkIP6nMask(source) and \ not check_mac(source) and not source.startswith("ipset:"): raise FirewallError(errors.INVALID_ADDR, source) if self.fw_config: for zone in self.fw_config.get_zones(): if zone == self.name: continue if source in self.fw_config.get_zone(zone).sources: raise FirewallError(errors.INVALID_ADDR, "source '{}' already bound to zone '{}'".format(source, zone)) def check_name(self, name): super(Zone, self).check_name(name) if name.startswith('/'): raise FirewallError(errors.INVALID_NAME, "'%s' can't start with '/'" % name) elif name.endswith('/'): raise FirewallError(errors.INVALID_NAME, "'%s' can't end with '/'" % name) elif name.count('/') > 1: raise FirewallError(errors.INVALID_NAME, "more than one '/' in '%s'" % name) else: if "/" in name: checked_name = name[:name.find('/')] else: checked_name = name if len(checked_name) > max_zone_name_len(): raise FirewallError(errors.INVALID_NAME, "Zone of '%s' has %d chars, max is %d %s" % ( name, len(checked_name), max_zone_name_len(), self.combined)) if self.fw_config: if checked_name in self.fw_config.get_policy_objects(): raise FirewallError(errors.NAME_CONFLICT, "Zones can't have the same name as a policy.") def combine(self, zone): self.combined = True self.filename = None self.version = "" self.short = "" self.description = "" for interface in zone.interfaces: if interface not in self.interfaces: self.interfaces.append(interface) for source in zone.sources: if source not in self.sources: self.sources.append(source) for service in zone.services: if service not in self.services: self.services.append(service) for port in zone.ports: if port not in self.ports: self.ports.append(port) for proto in zone.protocols: if proto not in self.protocols: self.protocols.append(proto) for icmp in zone.icmp_blocks: if icmp not in self.icmp_blocks: self.icmp_blocks.append(icmp) if zone.forward: self.forward = True if zone.masquerade: self.masquerade = True for forward in zone.forward_ports: if forward not in self.forward_ports: self.forward_ports.append(forward) for port in zone.source_ports: if port not in self.source_ports: self.source_ports.append(port) for rule in zone.rules: self.rules.append(rule) self.rules_str.append(str(rule)) if zone.icmp_block_inversion: self.icmp_block_inversion = True # PARSER class zone_ContentHandler(IO_Object_ContentHandler): def __init__(self, item): IO_Object_ContentHandler.__init__(self, item) self._rule = None self._rule_error = False self._limit_ok = None def startElement(self, name, attrs): IO_Object_ContentHandler.startElement(self, name, attrs) if self._rule_error: return self.item.parser_check_element_attrs(name, attrs) if common_startElement(self, name, attrs): return elif name == "zone": if "name" in attrs: log.warning("Ignoring deprecated attribute name='%s'", attrs["name"]) if "version" in attrs: self.item.version = attrs["version"] if "immutable" in attrs: log.warning("Ignoring deprecated attribute immutable='%s'", attrs["immutable"]) if "target" in attrs: target = attrs["target"] if target not in ZONE_TARGETS: raise FirewallError(errors.INVALID_TARGET, target) if target != "" and target != DEFAULT_ZONE_TARGET: self.item.target = target elif name == "forward": if self.item.forward: log.warning("Forward already set, ignoring.") else: self.item.forward = True elif name == "interface": if self._rule: log.warning('Invalid rule: interface use in rule.') self._rule_error = True return # zone bound to interface if "name" not in attrs: log.warning('Invalid interface: Name missing.') self._rule_error = True return if attrs["name"] not in self.item.interfaces: self.item.interfaces.append(attrs["name"]) else: log.warning("Interface '%s' already set, ignoring.", attrs["name"]) elif name == "source": if self._rule: if self._rule.source: log.warning("Invalid rule: More than one source in rule '%s', ignoring.", str(self._rule)) self._rule_error = True return invert = False if "invert" in attrs and \ attrs["invert"].lower() in [ "yes", "true" ]: invert = True addr = mac = ipset = None if "address" in attrs: addr = attrs["address"] if "mac" in attrs: mac = attrs["mac"] if "ipset" in attrs: ipset = attrs["ipset"] self._rule.source = rich.Rich_Source(addr, mac, ipset, invert=invert) return # zone bound to source if "address" not in attrs and "ipset" not in attrs: log.warning('Invalid source: No address no ipset.') return if "address" in attrs and "ipset" in attrs: log.warning('Invalid source: Address and ipset.') return if "family" in attrs: log.warning("Ignoring deprecated attribute family='%s'", attrs["family"]) if "invert" in attrs: log.warning('Invalid source: Invertion not allowed here.') return if "address" in attrs: if not checkIPnMask(attrs["address"]) and \ not checkIP6nMask(attrs["address"]) and \ not check_mac(attrs["address"]): raise FirewallError(errors.INVALID_ADDR, attrs["address"]) if "ipset" in attrs: entry = "ipset:%s" % attrs["ipset"] if entry not in self.item.sources: self.item.sources.append(entry) else: log.warning("Source '%s' already set, ignoring.", attrs["address"]) if "address" in attrs: entry = attrs["address"] if entry not in self.item.sources: self.item.sources.append(entry) else: log.warning("Source '%s' already set, ignoring.", attrs["address"]) elif name == "icmp-block-inversion": if self.item.icmp_block_inversion: log.warning("Icmp-Block-Inversion already set, ignoring.") else: self.item.icmp_block_inversion = True else: log.warning("Unknown XML element '%s'", name) return def endElement(self, name): IO_Object_ContentHandler.endElement(self, name) common_endElement(self, name) def zone_reader(filename, path, no_check_name=False): zone = Zone() if not filename.endswith(".xml"): raise FirewallError(errors.INVALID_NAME, "'%s' is missing .xml suffix" % filename) zone.name = filename[:-4] if not no_check_name: zone.check_name(zone.name) zone.filename = filename zone.path = path zone.builtin = False if path.startswith(config.ETC_FIREWALLD) else True zone.default = zone.builtin handler = zone_ContentHandler(zone) parser = sax.make_parser() parser.setContentHandler(handler) name = "%s/%s" % (path, filename) with open(name, "rb") as f: source = sax.InputSource(None) source.setByteStream(f) try: parser.parse(source) except sax.SAXParseException as msg: raise FirewallError(errors.INVALID_ZONE, "not a valid zone file: %s" % \ msg.getException()) del handler del parser if PY2: zone.encode_strings() return zone def zone_writer(zone, path=None): _path = path if path else zone.path if zone.filename: name = "%s/%s" % (_path, zone.filename) else: name = "%s/%s.xml" % (_path, zone.name) if os.path.exists(name): try: shutil.copy2(name, "%s.old" % name) except Exception as msg: log.error("Backup of file '%s' failed: %s", name, msg) dirpath = os.path.dirname(name) if dirpath.startswith(config.ETC_FIREWALLD) and not os.path.exists(dirpath): if not os.path.exists(config.ETC_FIREWALLD): os.mkdir(config.ETC_FIREWALLD, 0o750) os.mkdir(dirpath, 0o750) f = io.open(name, mode='wt', encoding='UTF-8') handler = IO_Object_XMLGenerator(f) handler.startDocument() # start zone element attrs = {} if zone.version and zone.version != "": attrs["version"] = zone.version if zone.target != DEFAULT_ZONE_TARGET: attrs["target"] = zone.target handler.startElement("zone", attrs) handler.ignorableWhitespace("\n") common_writer(zone, handler) # interfaces for interface in uniqify(zone.interfaces): handler.ignorableWhitespace(" ") handler.simpleElement("interface", { "name": interface }) handler.ignorableWhitespace("\n") # source for source in uniqify(zone.sources): handler.ignorableWhitespace(" ") if "ipset:" in source: handler.simpleElement("source", { "ipset": source[6:] }) else: handler.simpleElement("source", { "address": source }) handler.ignorableWhitespace("\n") # icmp-block-inversion if zone.icmp_block_inversion: handler.ignorableWhitespace(" ") handler.simpleElement("icmp-block-inversion", { }) handler.ignorableWhitespace("\n") # forward if zone.forward: handler.ignorableWhitespace(" ") handler.simpleElement("forward", { }) handler.ignorableWhitespace("\n") # end zone element handler.endElement("zone") handler.ignorableWhitespace("\n") handler.endDocument() f.close() del handler