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core
rich.py
# -*- coding: utf-8 -*- # # Copyright (C) 2013-2016 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__ = [ "Rich_Source", "Rich_Destination", "Rich_Service", "Rich_Port", "Rich_Protocol", "Rich_Masquerade", "Rich_IcmpBlock", "Rich_IcmpType", "Rich_SourcePort", "Rich_ForwardPort", "Rich_Log", "Rich_Audit", "Rich_Accept", "Rich_Reject", "Rich_Drop", "Rich_Mark", "Rich_Limit", "Rich_Rule" ] from firewall import functions from firewall.core.ipset import check_ipset_name from firewall.core.base import REJECT_TYPES from firewall import errors from firewall.errors import FirewallError class Rich_Source(object): def __init__(self, addr, mac, ipset, invert=False): self.addr = addr if self.addr == "": self.addr = None self.mac = mac if self.mac == "" or self.mac is None: self.mac = None elif self.mac is not None: self.mac = self.mac.upper() self.ipset = ipset if self.ipset == "": self.ipset = None self.invert = invert if self.addr is None and self.mac is None and self.ipset is None: raise FirewallError(errors.INVALID_RULE, "no address, mac and ipset") def __str__(self): ret = 'source%s ' % (" NOT" if self.invert else "") if self.addr is not None: return ret + 'address="%s"' % self.addr elif self.mac is not None: return ret + 'mac="%s"' % self.mac elif self.ipset is not None: return ret + 'ipset="%s"' % self.ipset else: raise FirewallError(errors.INVALID_RULE, "no address, mac and ipset") class Rich_Destination(object): def __init__(self, addr, ipset, invert=False): self.addr = addr if self.addr == "": self.addr = None self.ipset = ipset if self.ipset == "": self.ipset = None self.invert = invert if self.addr is None and self.ipset is None: raise FirewallError(errors.INVALID_RULE, "no address and ipset") def __str__(self): ret = 'destination%s ' % (" NOT" if self.invert else "") if self.addr is not None: return ret + 'address="%s"' % self.addr elif self.ipset is not None: return ret + 'ipset="%s"' % self.ipset else: raise FirewallError(errors.INVALID_RULE, "no address and ipset") class Rich_Service(object): def __init__(self, name): self.name = name def __str__(self): return 'service name="%s"' % (self.name) class Rich_Port(object): def __init__(self, port, protocol): self.port = port self.protocol = protocol def __str__(self): return 'port port="%s" protocol="%s"' % (self.port, self.protocol) class Rich_SourcePort(Rich_Port): def __str__(self): return 'source-port port="%s" protocol="%s"' % (self.port, self.protocol) class Rich_Protocol(object): def __init__(self, value): self.value = value def __str__(self): return 'protocol value="%s"' % (self.value) class Rich_Masquerade(object): def __init__(self): pass def __str__(self): return 'masquerade' class Rich_IcmpBlock(object): def __init__(self, name): self.name = name def __str__(self): return 'icmp-block name="%s"' % (self.name) class Rich_IcmpType(object): def __init__(self, name): self.name = name def __str__(self): return 'icmp-type name="%s"' % (self.name) class Rich_ForwardPort(object): def __init__(self, port, protocol, to_port, to_address): self.port = port self.protocol = protocol self.to_port = to_port self.to_address = to_address # replace None with "" in to_port and/or to_address if self.to_port is None: self.to_port = "" if self.to_address is None: self.to_address = "" def __str__(self): return 'forward-port port="%s" protocol="%s"%s%s' % \ (self.port, self.protocol, ' to-port="%s"' % self.to_port if self.to_port != "" else '', ' to-addr="%s"' % self.to_address if self.to_address != "" else '') class Rich_Log(object): def __init__(self, prefix=None, level=None, limit=None): #TODO check default level in iptables self.prefix = prefix self.level = level self.limit = limit def __str__(self): return 'log%s%s%s' % \ (' prefix="%s"' % (self.prefix) if self.prefix else "", ' level="%s"' % (self.level) if self.level else "", " %s" % self.limit if self.limit else "") class Rich_Audit(object): def __init__(self, limit=None): #TODO check default level in iptables self.limit = limit def __str__(self): return 'audit%s' % (" %s" % self.limit if self.limit else "") class Rich_Accept(object): def __init__(self, limit=None): self.limit = limit def __str__(self): return "accept%s" % (" %s" % self.limit if self.limit else "") class Rich_Reject(object): def __init__(self, _type=None, limit=None): self.type = _type self.limit = limit def __str__(self): return "reject%s%s" % (' type="%s"' % self.type if self.type else "", " %s" % self.limit if self.limit else "") def check(self, family): if self.type: if not family: raise FirewallError(errors.INVALID_RULE, "When using reject type you must specify also rule family.") if family in ['ipv4', 'ipv6'] and \ self.type not in REJECT_TYPES[family]: valid_types = ", ".join(REJECT_TYPES[family]) raise FirewallError(errors.INVALID_RULE, "Wrong reject type %s.\nUse one of: %s." % (self.type, valid_types)) class Rich_Drop(Rich_Accept): def __str__(self): return "drop%s" % (" %s" % self.limit if self.limit else "") class Rich_Mark(object): def __init__(self, _set, limit=None): self.set = _set self.limit = limit def __str__(self): return "mark set=%s%s" % (self.set, " %s" % self.limit if self.limit else "") def check(self): if self.set is not None: x = self.set else: raise FirewallError(errors.INVALID_MARK, "no value set") if "/" in x: splits = x.split("/") if len(splits) != 2: raise FirewallError(errors.INVALID_MARK, x) if not functions.checkUINT32(splits[0]) or \ not functions.checkUINT32(splits[1]): # value and mask are uint32 raise FirewallError(errors.INVALID_MARK, x) else: if not functions.checkUINT32(x): # value is uint32 raise FirewallError(errors.INVALID_MARK, x) DURATION_TO_MULT = { "s": 1, "m": 60, "h": 60 * 60, "d": 24 * 60 * 60, } class Rich_Limit(object): def __init__(self, value, burst=None): self.value = value self.burst = burst def check(self): self.value_parse() self.burst_parse() @property def value(self): return self._value @value.setter def value(self, value): if value is None: self._value = None return try: rate, duration = self._value_parse(value) except FirewallError: # The value is invalid. We cannot normalize it. v = value else: v = f"{rate}/{duration}" if getattr(self, "_value", None) != v: self._value = v @property def burst(self): return self._burst @burst.setter def burst(self, burst): if burst is None: self._burst = None return try: b = self._burst_parse(burst) except FirewallError: b = burst else: b = str(burst) if getattr(self, "_burst", None) != b: self._burst = b @staticmethod def _value_parse(value): splits = None if "/" in value: splits = value.split("/") if not splits or len(splits) != 2: raise FirewallError(errors.INVALID_LIMIT, value) (rate, duration) = splits try: rate = int(rate) except: raise FirewallError(errors.INVALID_LIMIT, value) if duration in ["second", "minute", "hour", "day"]: duration = duration[:1] if rate < 1 or duration not in ["s", "m", "h", "d"]: raise FirewallError(errors.INVALID_LIMIT, value) if 10000 * DURATION_TO_MULT[duration] // rate == 0: raise FirewallError(errors.INVALID_LIMIT, "%s too fast" % (value,)) if rate == 1 and duration == "d": # iptables (v1.4.21) doesn't accept 1/d raise FirewallError(errors.INVALID_LIMIT, "%s too slow" % (value,)) return rate, duration def value_parse(self): return self._value_parse(self._value) @staticmethod def _burst_parse(burst): if burst is None: return None try: b = int(burst) except: raise FirewallError(errors.INVALID_LIMIT, burst) if b < 1 or b > 10_000_000: raise FirewallError(errors.INVALID_LIMIT, burst) return b def burst_parse(self): return self._burst_parse(self._burst) def __str__(self): s = f'limit value="{self._value}"' if self._burst is not None: s += f" burst={self._burst}" return s class Rich_Rule(object): priority_min = -32768 priority_max = 32767 def __init__(self, family=None, rule_str=None, priority=0): if family is not None: self.family = str(family) else: self.family = None self.priority = priority self.source = None self.destination = None self.element = None self.log = None self.audit = None self.action = None if rule_str: self._import_from_string(rule_str) def _lexer(self, rule_str): """ Lexical analysis """ tokens = [] for r in functions.splitArgs(rule_str): if "=" in r: attr = r.split('=') if len(attr) != 2 or not attr[0] or not attr[1]: raise FirewallError(errors.INVALID_RULE, 'internal error in _lexer(): %s' % r) tokens.append({'attr_name':attr[0], 'attr_value':attr[1]}) else: tokens.append({'element':r}) tokens.append({'element':'EOL'}) return tokens def _import_from_string(self, rule_str): if not rule_str: raise FirewallError(errors.INVALID_RULE, 'empty rule') rule_str = functions.stripNonPrintableCharacters(rule_str) self.priority = 0 self.family = None self.source = None self.destination = None self.element = None self.log = None self.audit = None self.action = None tokens = self._lexer(rule_str) if tokens and tokens[0].get('element') == 'EOL': raise FirewallError(errors.INVALID_RULE, 'empty rule') attrs = {} # attributes of elements in_elements = [] # stack with elements we are in index = 0 # index into tokens while not (tokens[index].get('element') == 'EOL' and in_elements == ['rule']): element = tokens[index].get('element') attr_name = tokens[index].get('attr_name') attr_value = tokens[index].get('attr_value') #print ("in_elements: ", in_elements) #print ("index: %s, element: %s, attribute: %s=%s" % (index, element, attr_name, attr_value)) if attr_name: # attribute if attr_name not in ['priority', 'family', 'address', 'mac', 'ipset', 'invert', 'value', 'port', 'protocol', 'to-port', 'to-addr', 'name', 'prefix', 'level', 'type', 'set', 'burst']: raise FirewallError(errors.INVALID_RULE, "bad attribute '%s'" % attr_name) else: # element if element in ['rule', 'source', 'destination', 'protocol', 'service', 'port', 'icmp-block', 'icmp-type', 'masquerade', 'forward-port', 'source-port', 'log', 'audit', 'accept', 'drop', 'reject', 'mark', 'limit', 'not', 'NOT', 'EOL']: if element == 'source' and self.source: raise FirewallError(errors.INVALID_RULE, "more than one 'source' element") elif element == 'destination' and self.destination: raise FirewallError(errors.INVALID_RULE, "more than one 'destination' element") elif element in ['protocol', 'service', 'port', 'icmp-block', 'icmp-type', 'masquerade', 'forward-port', 'source-port'] and self.element: raise FirewallError(errors.INVALID_RULE, "more than one element. There cannot be both '%s' and '%s' in one rule." % (element, self.element)) elif element == 'log' and self.log: raise FirewallError(errors.INVALID_RULE, "more than one 'log' element") elif element == 'audit' and self.audit: raise FirewallError(errors.INVALID_RULE, "more than one 'audit' element") elif element in ['accept', 'drop', 'reject', 'mark'] and self.action: raise FirewallError(errors.INVALID_RULE, "more than one 'action' element. There cannot be both '%s' and '%s' in one rule." % (element, self.action)) else: raise FirewallError(errors.INVALID_RULE, "unknown element %s" % element) in_element = in_elements[len(in_elements)-1] if len(in_elements) > 0 else '' if in_element == '': if not element and attr_name: if attr_name == 'family': raise FirewallError(errors.INVALID_RULE, "'family' outside of rule. Use 'rule family=...'.") elif attr_name == 'priority': raise FirewallError(errors.INVALID_RULE, "'priority' outside of rule. Use 'rule priority=...'.") else: raise FirewallError(errors.INVALID_RULE, "'%s' outside of any element. Use 'rule <element> %s= ...'." % (attr_name, attr_name)) elif 'rule' not in element: raise FirewallError(errors.INVALID_RULE, "'%s' outside of rule. Use 'rule ... %s ...'." % (element, element)) else: in_elements.append('rule') # push into stack elif in_element == 'rule': if attr_name == 'family': if attr_value not in ['ipv4', 'ipv6']: raise FirewallError(errors.INVALID_RULE, "'family' attribute cannot have '%s' value. Use 'ipv4' or 'ipv6' instead." % attr_value) self.family = attr_value elif attr_name == 'priority': try: self.priority = int(attr_value) except ValueError: raise FirewallError(errors.INVALID_PRIORITY, "invalid 'priority' attribute value '%s'." % attr_value) elif attr_name: if attr_name == 'protocol': err_msg = "wrong 'protocol' usage. Use either 'rule protocol value=...' or 'rule [forward-]port protocol=...'." else: err_msg = "attribute '%s' outside of any element. Use 'rule <element> %s= ...'." % (attr_name, attr_name) raise FirewallError(errors.INVALID_RULE, err_msg) else: in_elements.append(element) # push into stack elif in_element == 'source': if attr_name in ['address', 'mac', 'ipset', 'invert']: attrs[attr_name] = attr_value elif element in ['not', 'NOT']: attrs['invert'] = True else: self.source = Rich_Source(attrs.get('address'), attrs.get('mac'), attrs.get('ipset'), attrs.get('invert', False)) in_elements.pop() # source attrs.clear() index = index -1 # return token to input elif in_element == 'destination': if attr_name in ['address', 'ipset', 'invert']: attrs[attr_name] = attr_value elif element in ['not', 'NOT']: attrs['invert'] = True else: self.destination = Rich_Destination(attrs.get('address'), attrs.get('ipset'), attrs.get('invert', False)) in_elements.pop() # destination attrs.clear() index = index -1 # return token to input elif in_element == 'protocol': if attr_name == 'value': self.element = Rich_Protocol(attr_value) in_elements.pop() # protocol else: raise FirewallError(errors.INVALID_RULE, "invalid 'protocol' element") elif in_element == 'service': if attr_name == 'name': self.element = Rich_Service(attr_value) in_elements.pop() # service else: raise FirewallError(errors.INVALID_RULE, "invalid 'service' element") elif in_element == 'port': if attr_name in ['port', 'protocol']: attrs[attr_name] = attr_value else: self.element = Rich_Port(attrs.get('port'), attrs.get('protocol')) in_elements.pop() # port attrs.clear() index = index -1 # return token to input elif in_element == 'icmp-block': if attr_name == 'name': self.element = Rich_IcmpBlock(attr_value) in_elements.pop() # icmp-block else: raise FirewallError(errors.INVALID_RULE, "invalid 'icmp-block' element") elif in_element == 'icmp-type': if attr_name == 'name': self.element = Rich_IcmpType(attr_value) in_elements.pop() # icmp-type else: raise FirewallError(errors.INVALID_RULE, "invalid 'icmp-type' element") elif in_element == 'masquerade': self.element = Rich_Masquerade() in_elements.pop() attrs.clear() index = index -1 # return token to input elif in_element == 'forward-port': if attr_name in ['port', 'protocol', 'to-port', 'to-addr']: attrs[attr_name] = attr_value else: self.element = Rich_ForwardPort(attrs.get('port'), attrs.get('protocol'), attrs.get('to-port'), attrs.get('to-addr')) in_elements.pop() # forward-port attrs.clear() index = index -1 # return token to input elif in_element == 'source-port': if attr_name in ['port', 'protocol']: attrs[attr_name] = attr_value else: self.element = Rich_SourcePort(attrs.get('port'), attrs.get('protocol')) in_elements.pop() # source-port attrs.clear() index = index -1 # return token to input elif in_element == 'log': if attr_name in ['prefix', 'level']: attrs[attr_name] = attr_value elif element == 'limit': in_elements.append('limit') else: self.log = Rich_Log(attrs.get('prefix'), attrs.get('level'), attrs.get('limit')) in_elements.pop() # log attrs.clear() index = index -1 # return token to input elif in_element == 'audit': if element == 'limit': in_elements.append('limit') else: self.audit = Rich_Audit(attrs.get('limit')) in_elements.pop() # audit attrs.clear() index = index -1 # return token to input elif in_element == 'accept': if element == 'limit': in_elements.append('limit') else: self.action = Rich_Accept(attrs.get('limit')) in_elements.pop() # accept attrs.clear() index = index -1 # return token to input elif in_element == 'drop': if element == 'limit': in_elements.append('limit') else: self.action = Rich_Drop(attrs.get('limit')) in_elements.pop() # drop attrs.clear() index = index -1 # return token to input elif in_element == 'reject': if attr_name == 'type': attrs[attr_name] = attr_value elif element == 'limit': in_elements.append('limit') else: self.action = Rich_Reject(attrs.get('type'), attrs.get('limit')) in_elements.pop() # accept attrs.clear() index = index -1 # return token to input elif in_element == 'mark': if attr_name == 'set': attrs[attr_name] = attr_value elif element == 'limit': in_elements.append('limit') else: self.action = Rich_Mark(attrs.get('set'), attrs.get('limit')) in_elements.pop() # accept attrs.clear() index = index -1 # return token to input elif in_element == 'limit': if attr_name in ["value", "burst"]: attrs[f"limit.{attr_name}"] = attr_value else: if "limit.value" not in attrs: raise FirewallError( errors.INVALID_RULE, "invalid 'limit' element" ) attrs["limit"] = Rich_Limit( attrs["limit.value"], attrs.get("limit.burst") ) attrs.pop("limit.value", None) attrs.pop("limit.burst", None) in_elements.pop() # limit index = index - 1 # return token to input index = index + 1 self.check() def check(self): if self.family is not None and self.family not in [ "ipv4", "ipv6" ]: raise FirewallError(errors.INVALID_FAMILY, self.family) if self.family is None: if (self.source is not None and self.source.addr is not None) or \ self.destination is not None: raise FirewallError(errors.MISSING_FAMILY) if type(self.element) == Rich_ForwardPort: raise FirewallError(errors.MISSING_FAMILY) if self.priority < self.priority_min or self.priority > self.priority_max: raise FirewallError(errors.INVALID_PRIORITY, "'priority' attribute must be between %d and %d." \ % (self.priority_min, self.priority_max)) if self.element is None and \ (self.log is None or (self.log is not None and self.priority == 0)): if self.action is None: raise FirewallError(errors.INVALID_RULE, "no element, no action") if self.source is None and self.destination is None and self.priority == 0: raise FirewallError(errors.INVALID_RULE, "no element, no source, no destination") if type(self.element) not in [ Rich_IcmpBlock, Rich_ForwardPort, Rich_Masquerade ]: if self.log is None and self.audit is None and \ self.action is None: raise FirewallError(errors.INVALID_RULE, "no action, no log, no audit") # source if self.source is not None: if self.source.addr is not None: if self.family is None: raise FirewallError(errors.INVALID_FAMILY) if self.source.mac is not None: raise FirewallError(errors.INVALID_RULE, "address and mac") if self.source.ipset is not None: raise FirewallError(errors.INVALID_RULE, "address and ipset") if not functions.check_address(self.family, self.source.addr): raise FirewallError(errors.INVALID_ADDR, str(self.source.addr)) elif self.source.mac is not None: if self.source.ipset is not None: raise FirewallError(errors.INVALID_RULE, "mac and ipset") if not functions.check_mac(self.source.mac): raise FirewallError(errors.INVALID_MAC, str(self.source.mac)) elif self.source.ipset is not None: if not check_ipset_name(self.source.ipset): raise FirewallError(errors.INVALID_IPSET, str(self.source.ipset)) else: raise FirewallError(errors.INVALID_RULE, "invalid source") # destination if self.destination is not None: if self.destination.addr is not None: if self.family is None: raise FirewallError(errors.INVALID_FAMILY) if self.destination.ipset is not None: raise FirewallError(errors.INVALID_DESTINATION, "address and ipset") if not functions.check_address(self.family, self.destination.addr): raise FirewallError(errors.INVALID_ADDR, str(self.destination.addr)) elif self.destination.ipset is not None: if not check_ipset_name(self.destination.ipset): raise FirewallError(errors.INVALID_IPSET, str(self.destination.ipset)) else: raise FirewallError(errors.INVALID_RULE, "invalid destination") # service if type(self.element) == Rich_Service: # service availability needs to be checked in Firewall, here is no # knowledge about this, therefore only simple check if self.element.name is None or len(self.element.name) < 1: raise FirewallError(errors.INVALID_SERVICE, str(self.element.name)) # port elif type(self.element) == Rich_Port: if not functions.check_port(self.element.port): raise FirewallError(errors.INVALID_PORT, self.element.port) if self.element.protocol not in [ "tcp", "udp", "sctp", "dccp" ]: raise FirewallError(errors.INVALID_PROTOCOL, self.element.protocol) # protocol elif type(self.element) == Rich_Protocol: if not functions.checkProtocol(self.element.value): raise FirewallError(errors.INVALID_PROTOCOL, self.element.value) # masquerade elif type(self.element) == Rich_Masquerade: if self.action is not None: raise FirewallError(errors.INVALID_RULE, "masquerade and action") if self.source is not None and self.source.mac is not None: raise FirewallError(errors.INVALID_RULE, "masquerade and mac source") # icmp-block elif type(self.element) == Rich_IcmpBlock: # icmp type availability needs to be checked in Firewall, here is no # knowledge about this, therefore only simple check if self.element.name is None or len(self.element.name) < 1: raise FirewallError(errors.INVALID_ICMPTYPE, str(self.element.name)) if self.action: raise FirewallError(errors.INVALID_RULE, "icmp-block and action") # icmp-type elif type(self.element) == Rich_IcmpType: # icmp type availability needs to be checked in Firewall, here is no # knowledge about this, therefore only simple check if self.element.name is None or len(self.element.name) < 1: raise FirewallError(errors.INVALID_ICMPTYPE, str(self.element.name)) # forward-port elif type(self.element) == Rich_ForwardPort: if not functions.check_port(self.element.port): raise FirewallError(errors.INVALID_PORT, self.element.port) if self.element.protocol not in [ "tcp", "udp", "sctp", "dccp" ]: raise FirewallError(errors.INVALID_PROTOCOL, self.element.protocol) if self.element.to_port == "" and self.element.to_address == "": raise FirewallError(errors.INVALID_PORT, self.element.to_port) if self.element.to_port != "" and \ not functions.check_port(self.element.to_port): raise FirewallError(errors.INVALID_PORT, self.element.to_port) if self.element.to_address != "" and \ not functions.check_single_address(self.family, self.element.to_address): raise FirewallError(errors.INVALID_ADDR, self.element.to_address) if self.family is None: raise FirewallError(errors.INVALID_FAMILY) if self.action is not None: raise FirewallError(errors.INVALID_RULE, "forward-port and action") # source-port elif type(self.element) == Rich_SourcePort: if not functions.check_port(self.element.port): raise FirewallError(errors.INVALID_PORT, self.element.port) if self.element.protocol not in [ "tcp", "udp", "sctp", "dccp" ]: raise FirewallError(errors.INVALID_PROTOCOL, self.element.protocol) # other element and not empty? elif self.element is not None: raise FirewallError(errors.INVALID_RULE, "Unknown element %s" % type(self.element)) # log if self.log is not None: if self.log.level and \ self.log.level not in [ "emerg", "alert", "crit", "error", "warning", "notice", "info", "debug" ]: raise FirewallError(errors.INVALID_LOG_LEVEL, self.log.level) if self.log.limit is not None: self.log.limit.check() # audit if self.audit is not None: if type(self.action) not in [ Rich_Accept, Rich_Reject, Rich_Drop ]: raise FirewallError(errors.INVALID_AUDIT_TYPE, type(self.action)) if self.audit.limit is not None: self.audit.limit.check() # action if self.action is not None: if type(self.action) == Rich_Reject: self.action.check(self.family) elif type(self.action) == Rich_Mark: self.action.check() if self.action.limit is not None: self.action.limit.check() def __str__(self): ret = 'rule' if self.priority: ret += ' priority="%d"' % self.priority if self.family: ret += ' family="%s"' % self.family if self.source: ret += " %s" % self.source if self.destination: ret += " %s" % self.destination if self.element: ret += " %s" % self.element if self.log: ret += " %s" % self.log if self.audit: ret += " %s" % self.audit if self.action: ret += " %s" % self.action return (functions.u2b(ret)) if functions.PY2 else ret #class Rich_RawRule(object): #class Rich_RuleSet(object): #class Rich_AddressList(object):
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