# Copyright (C) 2017 Nippon Telegraph and Telephone Corporation. # # 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 re import ryu.exception from ryu.lib.ofctl_utils import str_to_int from ryu.ofproto import nicira_ext def ofp_instruction_from_str(ofproto, action_str): """ Parse an ovs-ofctl style action string and return a list of jsondict representations of OFPInstructionActions, which can then be passed to ofproto_parser.ofp_instruction_from_jsondict. Please note that this is for making transition from ovs-ofctl easier. Please consider using OFPAction constructors when writing new codes. This function takes the following arguments. =========== ================================================= Argument Description =========== ================================================= ofproto An ofproto module. action_str An action string. =========== ================================================= """ action_re = re.compile("([a-z_]+)(\([^)]*\)|[^a-z_,()][^,()]*)*") result = [] while len(action_str): m = action_re.match(action_str) if not m: raise ryu.exception.OFPInvalidActionString(action_str=action_str) action_name = m.group(1) this_action = m.group(0) paren_level = this_action.count('(') - this_action.count(')') assert paren_level >= 0 try: # Parens can be nested. Look for as many ')'s as '('s. if paren_level > 0: this_action, rest = _tokenize_paren_block(action_str, m.end(0)) else: rest = action_str[m.end(0):] if len(rest): assert rest[0] == ',' rest = rest[1:] except Exception: raise ryu.exception.OFPInvalidActionString(action_str=action_str) if action_name == 'drop': assert this_action == 'drop' assert len(result) == 0 and rest == '' return [] converter = getattr(OfctlActionConverter, action_name, None) if converter is None or not callable(converter): raise ryu.exception.OFPInvalidActionString(action_str=action_name) result.append(converter(ofproto, this_action)) action_str = rest return result def _tokenize_paren_block(string, pos): paren_re = re.compile("[()]") paren_level = string[:pos].count('(') - string[:pos].count(')') while paren_level > 0: m = paren_re.search(string[pos:]) if m.group(0) == '(': paren_level += 1 else: paren_level -= 1 pos += m.end(0) return string[:pos], string[pos:] def tokenize_ofp_instruction_arg(arg): """ Tokenize an argument portion of ovs-ofctl style action string. """ arg_re = re.compile("[^,()]*") try: rest = arg result = [] while len(rest): m = arg_re.match(rest) if m.end(0) == len(rest): result.append(rest) return result if rest[m.end(0)] == '(': this_block, rest = _tokenize_paren_block( rest, m.end(0) + 1) result.append(this_block) elif rest[m.end(0)] == ',': result.append(m.group(0)) rest = rest[m.end(0):] else: # is ')' raise Exception if len(rest): assert rest[0] == ',' rest = rest[1:] return result except Exception: raise ryu.exception.OFPInvalidActionString(action_str=arg) _OXM_FIELD_OFCTL_ALIASES = { 'tun_id': 'tunnel_id', 'in_port': 'in_port_nxm', 'in_port_oxm': 'in_port', 'dl_src': 'eth_src', 'dl_type': 'eth_type', 'nw_src': 'ipv4_src', 'ip_src': 'ipv4_src', 'nw_proto': 'ip_proto', 'nw_ecn': 'ip_ecn', 'tp_src': 'tcp_src', 'icmp_type': 'icmpv4_type', 'icmp_code': 'icmpv4_code', 'nd_target': 'ipv6_nd_target', 'nd_sll': 'ipv6_nd_sll', 'nd_tll': 'ipv6_nd_tll', # Nicira extension 'tun_src': 'tun_ipv4_src' } def ofp_ofctl_field_name_to_ryu(field): """Convert an ovs-ofctl field name to ryu equivalent.""" mapped = _OXM_FIELD_OFCTL_ALIASES.get(field) if mapped: return mapped if field.endswith("_dst"): mapped = _OXM_FIELD_OFCTL_ALIASES.get(field[:-3] + "src") if mapped: return mapped[:-3] + "dst" return field _NXM_FIELD_MAP = dict([(key, key + '_nxm') for key in [ 'arp_sha', 'arp_tha', 'ipv6_src', 'ipv6_dst', 'icmpv6_type', 'icmpv6_code', 'ip_ecn', 'tcp_flags']]) _NXM_FIELD_MAP.update({ 'tun_id': 'tunnel_id_nxm', 'ip_ttl': 'nw_ttl'}) _NXM_OF_FIELD_MAP = dict([(key, key + '_nxm') for key in [ 'in_port', 'eth_dst', 'eth_src', 'eth_type', 'ip_proto', 'tcp_src', 'tcp_dst', 'udp_src', 'udp_dst', 'arp_op', 'arp_spa', 'arp_tpa']]) _NXM_OF_FIELD_MAP.update({ 'ip_src': 'ipv4_src_nxm', 'ip_dst': 'ipv4_dst_nxm', 'icmp_type': 'icmpv4_type_nxm', 'icmp_code': 'icmpv4_code_nxm'}) def nxm_field_name_to_ryu(field): """ Convert an ovs-ofctl style NXM_/OXM_ field name to a ryu match field name. """ if field.endswith("_W"): field = field[:-2] prefix = field[:7] field = field[7:].lower() mapped_result = None if prefix == 'NXM_NX_': mapped_result = _NXM_FIELD_MAP.get(field) elif prefix == "NXM_OF_": mapped_result = _NXM_OF_FIELD_MAP.get(field) elif prefix == "OXM_OF_": # no mapping needed pass else: raise ValueError if mapped_result is not None: return mapped_result return field class OfctlActionConverter(object): @classmethod def goto_table(cls, ofproto, action_str): assert action_str.startswith('goto_table:') table_id = str_to_int(action_str[len('goto_table:'):]) return dict(OFPInstructionGotoTable={'table_id': table_id}) @classmethod def normal(cls, ofproto, action_str): return cls.output(ofproto, action_str) @classmethod def output(cls, ofproto, action_str): if action_str == 'normal': port = ofproto.OFPP_NORMAL else: assert action_str.startswith('output:') port = str_to_int(action_str[len('output:'):]) return dict(OFPActionOutput={'port': port}) @classmethod def pop_vlan(cls, ofproto, action_str): return dict(OFPActionPopVlan={}) @classmethod def set_field(cls, ofproto, action_str): try: assert action_str.startswith("set_field:") value, key = action_str[len("set_field:"):].split("->", 1) fieldarg = dict(field=ofp_ofctl_field_name_to_ryu(key)) m = value.find('/') if m >= 0: fieldarg['value'] = str_to_int(value[:m]) fieldarg['mask'] = str_to_int(value[m + 1:]) else: fieldarg['value'] = str_to_int(value) except Exception: raise ryu.exception.OFPInvalidActionString(action_str=action_str) return dict(OFPActionSetField={ 'field': {'OXMTlv': fieldarg}}) # NX actions @classmethod def resubmit(cls, ofproto, action_str): arg = action_str[len("resubmit"):] kwargs = {} try: if arg[0] == ':': kwargs['in_port'] = str_to_int(arg[1:]) elif arg[0] == '(' and arg[-1] == ')': in_port, table_id = arg[1:-1].split(',') if in_port: kwargs['in_port'] = str_to_int(in_port) if table_id: kwargs['table_id'] = str_to_int(table_id) else: raise Exception return dict(NXActionResubmitTable=kwargs) except Exception: raise ryu.exception.OFPInvalidActionString( action_str=action_str) @classmethod def conjunction(cls, ofproto, action_str): try: assert action_str.startswith('conjunction(') assert action_str[-1] == ')' args = action_str[len('conjunction('):-1].split(',') assert len(args) == 2 id_ = str_to_int(args[0]) clauses = list(map(str_to_int, args[1].split('/'))) assert len(clauses) == 2 return dict(NXActionConjunction={ 'clause': clauses[0] - 1, 'n_clauses': clauses[1], 'id': id_}) except Exception: raise ryu.exception.OFPInvalidActionString( action_str=action_str) @classmethod def ct(cls, ofproto, action_str): str_to_port = {'ftp': 21, 'tftp': 69} flags = 0 zone_src = "" zone_ofs_nbits = 0 recirc_table = nicira_ext.NX_CT_RECIRC_NONE alg = 0 ct_actions = [] if len(action_str) > 2: if (not action_str.startswith('ct(') or action_str[-1] != ')'): raise ryu.exception.OFPInvalidActionString( action_str=action_str) rest = tokenize_ofp_instruction_arg(action_str[len('ct('):-1]) else: rest = [] for arg in rest: if arg == 'commit': flags |= nicira_ext.NX_CT_F_COMMIT rest = rest[len('commit'):] elif arg == 'force': flags |= nicira_ext.NX_CT_F_FORCE elif arg.startswith('exec('): ct_actions = ofp_instruction_from_str( ofproto, arg[len('exec('):-1]) else: try: k, v = arg.split('=', 1) if k == 'table': recirc_table = str_to_int(v) elif k == 'zone': m = re.search('\[(\d*)\.\.(\d*)\]', v) if m: zone_ofs_nbits = nicira_ext.ofs_nbits( int(m.group(1)), int(m.group(2))) zone_src = nxm_field_name_to_ryu( v[:m.start(0)]) else: zone_ofs_nbits = str_to_int(v) elif k == 'alg': alg = str_to_port[arg[len('alg='):]] except Exception: raise ryu.exception.OFPInvalidActionString( action_str=action_str) return dict(NXActionCT={'flags': flags, 'zone_src': zone_src, 'zone_ofs_nbits': zone_ofs_nbits, 'recirc_table': recirc_table, 'alg': alg, 'actions': ct_actions})