build.match.match_flows() - Code Metrics - Inspection of "Add support for non-strict exclusion in the consis..." - kytos/flow_manager - Measure and Improve Code Quality continuously with Scrutinizer

Test Failed

Pull Request — master (#117)

by Carlos

created 2021-04-06 15:47 UTC

build.match.match_flows() A

↳ Parent: build.match

Complexity

Conditions

Size

Total Lines	14
Code Lines	3

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	1
eloc	3
nop	3
dl	0
loc	14
rs	10
c	0
b	0
f	0

"""Switch match."""

import ipaddress

from pyof.v0x01.common.flow_match import FlowWildCards

IPV4_ETH_TYPE = 2048


def format_request(request):
    """Format user request to match function format."""
    args = {}
    for key, value in request.items():
        args[key] = value
    return args


def do_match(flow_to_install, version, stored_flow_dict):
    """Match a packet against this flow."""
    if version == 0x01:
        return match10(stored_flow_dict, flow_to_install)
    elif version == 0x04:
        return match13_no_strict(flow_to_install, stored_flow_dict)
    raise NotImplementedError(f'Unsupported OpenFlow version {version}')


def _get_match_fields(flow_dict):
    """Generate match fields."""
    match_fields = {}
    if 'match' in flow_dict:
        for key, value in flow_dict['match'].items():
            match_fields[key] = value
    return match_fields


# pylint: disable=too-many-return-statements, too-many-statements, R0912
def _match_ipv4(match_fields, args, wildcards):
    """Match IPV4."""
    if not match_fields['eth_type'] == IPV4_ETH_TYPE:
        return False
    flow_ip_int = int(ipaddress.IPv4Address(match_fields.get('ipv4_src')))
    if flow_ip_int != 0:
        mask = (wildcards
                & FlowWildCards.OFPFW_NW_SRC_MASK) >> \
                FlowWildCards.OFPFW_NW_SRC_SHIFT
        if mask > 32:
            mask = 32
        if mask != 32 and 'ipv4_src' not in args:
            return False
        mask = (0xffffffff << mask) & 0xffffffff
        ip_int = int(ipaddress.IPv4Address(args.get('ipv4_src')))
        if ip_int & mask != flow_ip_int & mask:
            return False

    flow_ip_int = int(ipaddress.IPv4Address(match_fields['ipv4_dst']))
    if flow_ip_int != 0:
        mask = (wildcards
                & FlowWildCards.OFPFW_NW_DST_MASK) >> \
                FlowWildCards.OFPFW_NW_DST_SHIFT
        if mask > 32:
            mask = 32
        if mask != 32 and 'ipv4_dst' not in args:
            return False
        mask = (0xffffffff << mask) & 0xffffffff
        ip_int = int(ipaddress.IPv4Address(args.get('ipv4_dst')))
        if ip_int & mask != flow_ip_int & mask:
            return False
    if not wildcards & FlowWildCards.OFPFW_NW_TOS:
        if 'ip_tos' not in args:
            return False
        if match_fields.get('ip_tos') != int(args.get('ip_tos')):
            return False
    if not wildcards & FlowWildCards.OFPFW_NW_PROTO:
        if 'ip_proto' not in args:
            return False
        if match_fields.get('ip_proto') != int(args.get('ip_proto')):
            return False
    if not wildcards & FlowWildCards.OFPFW_TP_SRC:
        if 'tp_src' not in args:
            return False
        if match_fields.get('tcp_src') != int(args.get('tp_src')):
            return False
    if not wildcards & FlowWildCards.OFPFW_TP_DST:
        if 'tp_dst' not in args:
            return False
        if match_fields.get('tcp_dst') != int(args.get('tp_dst')):
            return False
    return True


# pylint: disable=too-many-return-statements, too-many-statements, R0912
def match10(flow_dict, args):
    """Match a packet against this flow (OF1.0)."""
    match_fields = _get_match_fields(flow_dict)
    wildcards = match_fields.get('wildcards')
    if not wildcards & FlowWildCards.OFPFW_IN_PORT:
        if 'in_port' not in args:
            return False
        if match_fields.get('in_port') != int(args.get('in_port')):
            return False
    if not wildcards & FlowWildCards.OFPFW_DL_VLAN_PCP:
        if 'vlan_pcp' not in args:
            return False
        if match_fields.get('vlan_pcp') != int(args.get('vlan_pcp')):
            return False
    if not wildcards & FlowWildCards.OFPFW_DL_VLAN:
        if 'vlan_vid' not in args:
            return False
        if match_fields.get('vlan_vid') != args.get('vlan_vid')[-1]:
            return False
    if not wildcards & FlowWildCards.OFPFW_DL_SRC:
        if 'eth_src' not in args:
            return False
        if match_fields.get('eth_src') != args.get('eth_src'):
            return False
    if not wildcards & FlowWildCards.OFPFW_DL_DST:
        if 'eth_dst' not in args:
            return False
        if match_fields.get('eth_dst') != args.get('eth_dst'):
            return False
    if not wildcards & FlowWildCards.OFPFW_DL_TYPE:
        if 'eth_type' not in args:
            return False
        if match_fields.get('eth_type') != int(args.get('eth_type')):
            return False
    if not _match_ipv4(match_fields, args, wildcards):
        return False
    return flow_dict

    # def match13(self, args):
    #     """Match a packet against this flow (OF1.3)."""
    #     for name in self.match:
    #         if name not in args:
    #             return False
    #         if name == 'vlan_vid':
    #             field = args[name][-1]
    #         else:
    #             field = args[name]
    #         if name not in ('ipv4_src', 'ipv4_dst', 'ipv6_src', 'ipv6_dst'):
    #             if self.match[name].value != field:
    #                 return False
    #         else:
    #             packet_ip = int(ipaddress.ip_address(field))
    #             ip_addr = self.match[name].value
    #             if packet_ip & ip_addr.netmask != ip_addr.address:
    #                 return False
    #     return self


def match13_no_strict(flow_to_install, stored_flow_dict):
    """Match a packet againts the stored flow (OF 1.3).
    Return the flow if any fields match, otherwise, return False.
    """
    if flow_to_install.get('cookie_mask') and 'cookie' in stored_flow_dict:
        cookie = flow_to_install['cookie_mask'] & flow_to_install['cookie']
        if cookie == stored_flow_dict['cookie']:
            return stored_flow_dict
        return False

    if 'match' not in flow_to_install:
        return False

    for key, value in flow_to_install.get('match').items():
        if 'match' in stored_flow_dict:
            if value == stored_flow_dict['match'].get(key):
                return stored_flow_dict
    return None


def match_flows(flow_to_install, version, stored_flow_dict):
    # pylint: disable=bad-staticmethod-argument
    """
    Match the packet in request against the flows installed in the switch.

    Try the match with each flow, in other. If many is True, tries the
    match with all flows, if False, tries until the first match.
    :param args: packet data
    :param many: Boolean, indicating whether to continue after matching the
            first flow or not
    :return: If many, the list of matched flows, or the matched flow
    """
    match = do_match(flow_to_install, version, stored_flow_dict)
    return match


1			"""Switch match."""
2
3			import ipaddress
4
5			from pyof.v0x01.common.flow_match import FlowWildCards
6
7			IPV4_ETH_TYPE = 2048
8
9
10			def format_request(request):
11			"""Format user request to match function format."""
12			args = {}
13			for key, value in request.items():
14			args[key] = value
15			return args
16
17
18			def do_match(flow_to_install, version, stored_flow_dict):
19			"""Match a packet against this flow."""
20			if version == 0x01:
21			return match10(stored_flow_dict, flow_to_install)
22			elif version == 0x04:
23			return match13_no_strict(flow_to_install, stored_flow_dict)
24			raise NotImplementedError(f'Unsupported OpenFlow version {version}')
25
26
27			def _get_match_fields(flow_dict):
28			"""Generate match fields."""
29			match_fields = {}
30			if 'match' in flow_dict:
31			for key, value in flow_dict['match'].items():
32			match_fields[key] = value
33			return match_fields
34
35
36			# pylint: disable=too-many-return-statements, too-many-statements, R0912
37			def _match_ipv4(match_fields, args, wildcards):
38			"""Match IPV4."""
39			if not match_fields['eth_type'] == IPV4_ETH_TYPE:
40			return False
41			flow_ip_int = int(ipaddress.IPv4Address(match_fields.get('ipv4_src')))
42			if flow_ip_int != 0:
43			mask = (wildcards
44			& FlowWildCards.OFPFW_NW_SRC_MASK) >> \
45			FlowWildCards.OFPFW_NW_SRC_SHIFT
46			if mask > 32:
47			mask = 32
48			if mask != 32 and 'ipv4_src' not in args:
49			return False
50			mask = (0xffffffff << mask) & 0xffffffff
51			ip_int = int(ipaddress.IPv4Address(args.get('ipv4_src')))
52			if ip_int & mask != flow_ip_int & mask:
53			return False
54
55			flow_ip_int = int(ipaddress.IPv4Address(match_fields['ipv4_dst']))
56			if flow_ip_int != 0:
57			mask = (wildcards
58			& FlowWildCards.OFPFW_NW_DST_MASK) >> \
59			FlowWildCards.OFPFW_NW_DST_SHIFT
60			if mask > 32:
61			mask = 32
62			if mask != 32 and 'ipv4_dst' not in args:
63			return False
64			mask = (0xffffffff << mask) & 0xffffffff
65			ip_int = int(ipaddress.IPv4Address(args.get('ipv4_dst')))
66			if ip_int & mask != flow_ip_int & mask:
67			return False
68			if not wildcards & FlowWildCards.OFPFW_NW_TOS:
69			if 'ip_tos' not in args:
70			return False
71			if match_fields.get('ip_tos') != int(args.get('ip_tos')):
72			return False
73			if not wildcards & FlowWildCards.OFPFW_NW_PROTO:
74			if 'ip_proto' not in args:
75			return False
76			if match_fields.get('ip_proto') != int(args.get('ip_proto')):
77			return False
78			if not wildcards & FlowWildCards.OFPFW_TP_SRC:
79			if 'tp_src' not in args:
80			return False
81			if match_fields.get('tcp_src') != int(args.get('tp_src')):
82			return False
83			if not wildcards & FlowWildCards.OFPFW_TP_DST:
84			if 'tp_dst' not in args:
85			return False
86			if match_fields.get('tcp_dst') != int(args.get('tp_dst')):
87			return False
88			return True
89
90
91			# pylint: disable=too-many-return-statements, too-many-statements, R0912
92			def match10(flow_dict, args):
93			"""Match a packet against this flow (OF1.0)."""
94			match_fields = _get_match_fields(flow_dict)
95			wildcards = match_fields.get('wildcards')
96			if not wildcards & FlowWildCards.OFPFW_IN_PORT:
97			if 'in_port' not in args:
98			return False
99			if match_fields.get('in_port') != int(args.get('in_port')):
100			return False
101			if not wildcards & FlowWildCards.OFPFW_DL_VLAN_PCP:
102			if 'vlan_pcp' not in args:
103			return False
104			if match_fields.get('vlan_pcp') != int(args.get('vlan_pcp')):
105			return False
106			if not wildcards & FlowWildCards.OFPFW_DL_VLAN:
107			if 'vlan_vid' not in args:
108			return False
109			if match_fields.get('vlan_vid') != args.get('vlan_vid')[-1]:
110			return False
111			if not wildcards & FlowWildCards.OFPFW_DL_SRC:
112			if 'eth_src' not in args:
113			return False
114			if match_fields.get('eth_src') != args.get('eth_src'):
115			return False
116			if not wildcards & FlowWildCards.OFPFW_DL_DST:
117			if 'eth_dst' not in args:
118			return False
119			if match_fields.get('eth_dst') != args.get('eth_dst'):
120			return False
121			if not wildcards & FlowWildCards.OFPFW_DL_TYPE:
122			if 'eth_type' not in args:
123			return False
124			if match_fields.get('eth_type') != int(args.get('eth_type')):
125			return False
126			if not _match_ipv4(match_fields, args, wildcards):
127			return False
128			return flow_dict
129
130			# def match13(self, args):
131			# """Match a packet against this flow (OF1.3)."""
132			# for name in self.match:
133			# if name not in args:
134			# return False
135			# if name == 'vlan_vid':
136			# field = args[name][-1]
137			# else:
138			# field = args[name]
139			# if name not in ('ipv4_src', 'ipv4_dst', 'ipv6_src', 'ipv6_dst'):
140			# if self.match[name].value != field:
141			# return False
142			# else:
143			# packet_ip = int(ipaddress.ip_address(field))
144			# ip_addr = self.match[name].value
145			# if packet_ip & ip_addr.netmask != ip_addr.address:
146			# return False
147			# return self
148
149
150			def match13_no_strict(flow_to_install, stored_flow_dict):
151			"""Match a packet againts the stored flow (OF 1.3).
152			Return the flow if any fields match, otherwise, return False.
153			"""
154			if flow_to_install.get('cookie_mask') and 'cookie' in stored_flow_dict:
155			cookie = flow_to_install['cookie_mask'] & flow_to_install['cookie']
156			if cookie == stored_flow_dict['cookie']:
157			return stored_flow_dict
158			return False
159
160			if 'match' not in flow_to_install:
161			return False
162
163			for key, value in flow_to_install.get('match').items():
164			if 'match' in stored_flow_dict:
165			if value == stored_flow_dict['match'].get(key):
166			return stored_flow_dict
167			return None
168
169
170			def match_flows(flow_to_install, version, stored_flow_dict):
171			# pylint: disable=bad-staticmethod-argument
172			"""
173			Match the packet in request against the flows installed in the switch.
174
175			Try the match with each flow, in other. If many is True, tries the
176			match with all flows, if False, tries until the first match.
177			:param args: packet data
178			:param many: Boolean, indicating whether to continue after matching the
179			first flow or not
180			:return: If many, the list of matched flows, or the matched flow
181			"""
182			match = do_match(flow_to_install, version, stored_flow_dict)
183			return match
184

kytos / flow_manager

Pull Request — master (#117)

build.match.match_flows() A

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