# -*- 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/>. # import xml.sax as sax import os import io import shutil from firewall import config from firewall.fw_types import LastUpdatedOrderedDict from firewall.functions import splitArgs, joinArgs from firewall.core.io.io_object import IO_Object, IO_Object_ContentHandler, \ IO_Object_XMLGenerator from firewall.core.logger import log from firewall.core import ipXtables from firewall.core import ebtables from firewall import errors from firewall.errors import FirewallError class direct_ContentHandler(IO_Object_ContentHandler): def __init__(self, item): IO_Object_ContentHandler.__init__(self, item) self.direct = False def startElement(self, name, attrs): IO_Object_ContentHandler.startElement(self, name, attrs) self.item.parser_check_element_attrs(name, attrs) if name == "direct": if self.direct: raise FirewallError(errors.PARSE_ERROR, "More than one direct tag.") self.direct = True elif name == "chain": if not self.direct: log.error("Parse Error: chain outside of direct") return ipv = attrs["ipv"] table = attrs["table"] chain = attrs["chain"] self.item.add_chain(ipv, table, chain) elif name == "rule": if not self.direct: log.error("Parse Error: rule outside of direct") return ipv = attrs["ipv"] if ipv not in [ "ipv4", "ipv6", "eb" ]: raise FirewallError(errors.INVALID_IPV, "'%s' not from {'ipv4'|'ipv6'|'eb'}" % ipv) table = attrs["table"] chain = attrs["chain"] try: priority = int(attrs["priority"]) except ValueError: log.error("Parse Error: %s is not a valid priority" % attrs["priority"]) return self._rule = [ ipv, table, chain, priority ] elif name == "passthrough": if not self.direct: log.error("Parse Error: command outside of direct") return ipv = attrs["ipv"] self._passthrough = [ ipv ] else: log.error('Unknown XML element %s' % name) return def endElement(self, name): IO_Object_ContentHandler.endElement(self, name) if name == "rule": if self._element: # add arguments self._rule.append(splitArgs(self._element)) self.item.add_rule(*self._rule) else: log.error("Error: rule does not have any arguments, ignoring.") self._rule = None elif name == "passthrough": if self._element: # add arguments self._passthrough.append(splitArgs(self._element)) self.item.add_passthrough(*self._passthrough) else: log.error("Error: passthrough does not have any arguments, " + "ignoring.") self._passthrough = None class Direct(IO_Object): """ Direct class """ IMPORT_EXPORT_STRUCTURE = ( # chain: [ ipv, table, [ chain ] ] ( "chains", [ ( "", "", "" ), ], ), # a(sss) # rule: [ ipv, table, chain, [ priority, [ arg ] ] ] ( "rules", [ ( "", "", "", 0, [ "" ] ), ], ), # a(sssias) # passthrough: [ ipv, [ [ arg ] ] ] ( "passthroughs", [ ( "", [ "" ]), ], ), # a(sas) ) DBUS_SIGNATURE = '(a(sss)a(sssias)a(sas))' PARSER_REQUIRED_ELEMENT_ATTRS = { "direct": None, "chain": [ "ipv", "table", "chain" ], "rule": [ "ipv", "table", "chain", "priority" ], "passthrough": [ "ipv" ] } PARSER_OPTIONAL_ELEMENT_ATTRS = { } def __init__(self, filename): super(Direct, self).__init__() self.filename = filename self.chains = LastUpdatedOrderedDict() self.rules = LastUpdatedOrderedDict() self.passthroughs = LastUpdatedOrderedDict() def _check_config(self, conf, item, all_conf, all_io_objects): pass # check arg lists def export_config(self): ret = [ ] x = [ ] for key in self.chains: for chain in self.chains[key]: x.append(tuple(list(key) + list([chain]))) ret.append(x) x = [ ] for key in self.rules: for rule in self.rules[key]: x.append(tuple((key[0], key[1], key[2], rule[0], list(rule[1])))) ret.append(x) x = [ ] for key in self.passthroughs: for rule in self.passthroughs[key]: x.append(tuple((key, list(rule)))) ret.append(x) return tuple(ret) def import_config(self, conf, all_io_objects): self.cleanup() self.check_config(conf) for i,(element,dummy) in enumerate(self.IMPORT_EXPORT_STRUCTURE): if element == "chains": for x in conf[i]: self.add_chain(*x) if element == "rules": for x in conf[i]: self.add_rule(*x) if element == "passthroughs": for x in conf[i]: self.add_passthrough(*x) def cleanup(self): self.chains.clear() self.rules.clear() self.passthroughs.clear() def output(self): print("chains") for key in self.chains: print(" (%s, %s): %s" % (key[0], key[1], ",".join(self.chains[key]))) print("rules") for key in self.rules: print(" (%s, %s, %s):" % (key[0], key[1], key[2])) for (priority,args) in self.rules[key]: print(" (%d, ('%s'))" % (priority, "','".join(args))) print("passthroughs") for key in self.passthroughs: print(" %s:" % (key)) for args in self.passthroughs[key]: print(" ('%s')" % ("','".join(args))) def _check_ipv(self, ipv): ipvs = ['ipv4', 'ipv6', 'eb'] if ipv not in ipvs: raise FirewallError(errors.INVALID_IPV, "'%s' not in '%s'" % (ipv, ipvs)) def _check_ipv_table(self, ipv, table): self._check_ipv(ipv) tables = ipXtables.BUILT_IN_CHAINS.keys() if ipv in ['ipv4', 'ipv6'] \ else ebtables.BUILT_IN_CHAINS.keys() if table not in tables: raise FirewallError(errors.INVALID_TABLE, "'%s' not in '%s'" % (table, tables)) # chains def add_chain(self, ipv, table, chain): self._check_ipv_table(ipv, table) key = (ipv, table) if key not in self.chains: self.chains[key] = [ ] if chain not in self.chains[key]: self.chains[key].append(chain) else: log.warning("Chain '%s' for table '%s' with ipv '%s' " % \ (chain, table, ipv) + "already in list, ignoring") def remove_chain(self, ipv, table, chain): self._check_ipv_table(ipv, table) key = (ipv, table) if key in self.chains and chain in self.chains[key]: self.chains[key].remove(chain) if len(self.chains[key]) == 0: del self.chains[key] else: raise ValueError( \ "Chain '%s' with table '%s' with ipv '%s' not in list" % \ (chain, table, ipv)) def query_chain(self, ipv, table, chain): self._check_ipv_table(ipv, table) key = (ipv, table) return (key in self.chains and chain in self.chains[key]) def get_chains(self, ipv, table): self._check_ipv_table(ipv, table) key = (ipv, table) if key in self.chains: return self.chains[key] else: raise ValueError("No chains for table '%s' with ipv '%s'" % \ (table, ipv)) def get_all_chains(self): return self.chains # rules def add_rule(self, ipv, table, chain, priority, args): self._check_ipv_table(ipv, table) key = (ipv, table, chain) if key not in self.rules: self.rules[key] = LastUpdatedOrderedDict() value = (priority, tuple(args)) if value not in self.rules[key]: self.rules[key][value] = priority else: log.warning("Rule '%s' for table '%s' and chain '%s' " % \ ("',".join(args), table, chain) + "with ipv '%s' and priority %d " % (ipv, priority) + "already in list, ignoring") def remove_rule(self, ipv, table, chain, priority, args): self._check_ipv_table(ipv, table) key = (ipv, table, chain) value = (priority, tuple(args)) if key in self.rules and value in self.rules[key]: del self.rules[key][value] if len(self.rules[key]) == 0: del self.rules[key] else: raise ValueError("Rule '%s' for table '%s' and chain '%s' " % \ ("',".join(args), table, chain) + \ "with ipv '%s' and priority %d not in list" % (ipv, priority)) def remove_rules(self, ipv, table, chain): self._check_ipv_table(ipv, table) key = (ipv, table, chain) if key in self.rules: for value in self.rules[key].keys(): del self.rules[key][value] if len(self.rules[key]) == 0: del self.rules[key] def query_rule(self, ipv, table, chain, priority, args): self._check_ipv_table(ipv, table) key = (ipv, table, chain) value = (priority, tuple(args)) return (key in self.rules and value in self.rules[key]) def get_rules(self, ipv, table, chain): self._check_ipv_table(ipv, table) key = (ipv, table, chain) if key in self.rules: return self.rules[key] else: raise ValueError("No rules for table '%s' and chain '%s' " %\ (table, chain) + "with ipv '%s'" % (ipv)) def get_all_rules(self): return self.rules # # passthrough # def add_passthrough(self, ipv, args): self._check_ipv(ipv) if ipv not in self.passthroughs: self.passthroughs[ipv] = [ ] if args not in self.passthroughs[ipv]: self.passthroughs[ipv].append(args) else: log.warning("Passthrough '%s' for ipv '%s'" % \ ("',".join(args), ipv) + "already in list, ignoring") def remove_passthrough(self, ipv, args): self._check_ipv(ipv) if ipv in self.passthroughs and args in self.passthroughs[ipv]: self.passthroughs[ipv].remove(args) if len(self.passthroughs[ipv]) == 0: del self.passthroughs[ipv] else: raise ValueError("Passthrough '%s' for ipv '%s'" % \ ("',".join(args), ipv) + "not in list") def query_passthrough(self, ipv, args): self._check_ipv(ipv) return ipv in self.passthroughs and args in self.passthroughs[ipv] def get_passthroughs(self, ipv): self._check_ipv(ipv) if ipv in self.passthroughs: return self.passthroughs[ipv] else: raise ValueError("No passthroughs for ipv '%s'" % (ipv)) def get_all_passthroughs(self): return self.passthroughs # read def read(self): self.cleanup() if not self.filename.endswith(".xml"): raise FirewallError(errors.INVALID_NAME, "'%s' is missing .xml suffix" % self.filename) handler = direct_ContentHandler(self) parser = sax.make_parser() parser.setContentHandler(handler) with open(self.filename, "rb") as f: source = sax.InputSource(None) source.setByteStream(f) try: parser.parse(source) except sax.SAXParseException as msg: raise FirewallError(errors.INVALID_TYPE, "Not a valid file: %s" % \ msg.getException()) def write(self): if os.path.exists(self.filename): try: shutil.copy2(self.filename, "%s.old" % self.filename) except Exception as msg: raise IOError("Backup of '%s' failed: %s" % (self.filename, msg)) if not os.path.exists(config.ETC_FIREWALLD): os.mkdir(config.ETC_FIREWALLD, 0o750) f = io.open(self.filename, mode='wt', encoding='UTF-8') handler = IO_Object_XMLGenerator(f) handler.startDocument() # start whitelist element handler.startElement("direct", { }) handler.ignorableWhitespace("\n") # chains for key in self.chains: (ipv, table) = key for chain in self.chains[key]: handler.ignorableWhitespace(" ") handler.simpleElement("chain", { "ipv": ipv, "table": table, "chain": chain }) handler.ignorableWhitespace("\n") # rules for key in self.rules: (ipv, table, chain) = key for (priority, args) in self.rules[key]: if len(args) < 1: continue handler.ignorableWhitespace(" ") handler.startElement("rule", { "ipv": ipv, "table": table, "chain": chain, "priority": "%d" % priority }) handler.ignorableWhitespace(sax.saxutils.escape(joinArgs(args))) handler.endElement("rule") handler.ignorableWhitespace("\n") # passthroughs for ipv in self.passthroughs: for args in self.passthroughs[ipv]: if len(args) < 1: continue handler.ignorableWhitespace(" ") handler.startElement("passthrough", { "ipv": ipv }) handler.ignorableWhitespace(sax.saxutils.escape(joinArgs(args))) handler.endElement("passthrough") handler.ignorableWhitespace("\n") # end zone element handler.endElement("direct") handler.ignorableWhitespace("\n") handler.endDocument() f.close() del handler