1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
|
# -*- coding: utf-8 -*-
# Copyright (c) 2021, Felix Fontein <felix@fontein.de>
# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
# SPDX-License-Identifier: GPL-3.0-or-later
from __future__ import absolute_import, division, print_function
__metaclass__ = type
import os.path
import re
from ansible_collections.community.dns.plugins.module_utils.names import InvalidDomainName, split_into_labels, normalize_label
_BEGIN_SUBSET_MATCHER = re.compile(r'===BEGIN ([^=]*) DOMAINS===')
_END_SUBSET_MATCHER = re.compile(r'===END ([^=]*) DOMAINS===')
class PublicSuffixEntry(object):
'''
Contains a Public Suffix List entry with metadata.
'''
def __init__(self, labels, exception_rule=False, part=None):
self.labels = labels
self.exception_rule = exception_rule
self.part = part
def matches(self, normalized_labels):
'''
Match PSL entry with a given normalized list of labels.
'''
if len(normalized_labels) < len(self.labels):
return False
for i, label in enumerate(self.labels):
normalized_label = normalized_labels[i]
if label not in (normalized_label, '*'):
return False
return True
def select_prevailing_rule(rules):
'''
Given a non-empty set of rules matching a domain name, finds the prevailing rule.
It uses the algorithm specified on https://publicsuffix.org/list/.
'''
max_length_rule = rules[0]
max_length = len(max_length_rule.labels)
for rule in rules:
if rule.exception_rule:
return rule
if len(rule.labels) > max_length:
max_length = len(rule.labels)
max_length_rule = rule
return max_length_rule
class PublicSuffixList(object):
'''
Contains the Public Suffix List.
'''
def __init__(self, rules):
self._generic_rule = PublicSuffixEntry(('*', ))
self._rules = sorted(rules, key=lambda entry: entry.labels)
@classmethod
def load(cls, filename):
'''
Load Public Suffix List from the given filename.
'''
rules = []
part = None
with open(filename, 'rb') as content_file:
content = content_file.read().decode('utf-8')
for line in content.splitlines():
line = line.strip()
if line.startswith('//') or not line:
m = _BEGIN_SUBSET_MATCHER.search(line)
if m:
part = m.group(1).lower()
m = _END_SUBSET_MATCHER.search(line)
if m:
part = None
continue
if part is None:
raise Exception('Internal error: found PSL entry with no part!')
exception_rule = False
if line.startswith('!'):
exception_rule = True
line = line[1:]
if line.startswith('.'):
line = line[1:]
labels = tuple(normalize_label(label) for label in split_into_labels(line)[0])
rules.append(PublicSuffixEntry(labels, exception_rule=exception_rule, part=part))
return cls(rules)
def get_suffix_length_and_rule(self, normalized_labels, icann_only=False):
'''
Given a list of normalized labels, searches for a matching rule.
Returns the tuple ``(suffix_length, rule)``. The ``rule`` is never ``None``
except if ``normalized_labels`` is empty, in which case ``(0, None)`` is returned.
If ``icann_only`` is set to ``True``, only official ICANN rules are used. If
``icann_only`` is ``False`` (default), also private rules are used.
'''
if not normalized_labels:
return 0, None
# Find matching rules
rules = []
for rule in self._rules:
if icann_only and rule.part != 'icann':
continue
if rule.matches(normalized_labels):
rules.append(rule)
if not rules:
rules.append(self._generic_rule)
# Select prevailing rule
rule = select_prevailing_rule(rules)
# Determine suffix
suffix_length = len(rule.labels)
if rule.exception_rule:
suffix_length -= 1
# Return result
return suffix_length, rule
def get_suffix(self, domain, keep_unknown_suffix=True, normalize_result=False,
icann_only=False):
'''
Given a domain name, extracts the public suffix.
If ``keep_unknown_suffix`` is set to ``False``, only suffixes matching explicit
entries from the PSL are returned. If ``keep_unknown_suffix`` is ``True`` (default),
the implicit ``*`` rule is used if no other rule matches.
If ``normalize_result`` is set to ``True``, the result is re-combined form the
normalized labels. In that case, the result is lower-case ASCII. If
``normalize_result`` is ``False`` (default), the result ``result`` always satisfies
``domain.endswith(result)``.
If ``icann_only`` is set to ``True``, only official ICANN rules are used. If
``icann_only`` is ``False`` (default), also private rules are used.
'''
# Split into labels and normalize
try:
labels, tail = split_into_labels(domain)
normalized_labels = [normalize_label(label) for label in labels]
except InvalidDomainName:
return ''
if normalize_result:
labels = normalized_labels
# Get suffix length
suffix_length, rule = self.get_suffix_length_and_rule(normalized_labels, icann_only=icann_only)
if rule is None:
return ''
if not keep_unknown_suffix and rule is self._generic_rule:
return ''
return '.'.join(reversed(labels[:suffix_length])) + tail
def get_registrable_domain(self, domain, keep_unknown_suffix=True, only_if_registerable=True,
normalize_result=False, icann_only=False):
'''
Given a domain name, extracts the registrable domain. This is the public suffix
including the last label before the suffix.
If ``keep_unknown_suffix`` is set to ``False``, only suffixes matching explicit
entries from the PSL are returned. If no suffix can be found, ``''`` is returned.
If ``keep_unknown_suffix`` is ``True`` (default), the implicit ``*`` rule is used
if no other rule matches.
If ``only_if_registerable`` is set to ``False``, the public suffix is returned
if there is no label before the suffix. If ``only_if_registerable`` is ``True``
(default), ``''`` is returned in that case.
If ``normalize_result`` is set to ``True``, the result is re-combined form the
normalized labels. In that case, the result is lower-case ASCII. If
``normalize_result`` is ``False`` (default), the result ``result`` always satisfies
``domain.endswith(result)``.
If ``icann_only`` is set to ``True``, only official ICANN rules are used. If
``icann_only`` is ``False`` (default), also private rules are used.
'''
# Split into labels and normalize
try:
labels, tail = split_into_labels(domain)
normalized_labels = [normalize_label(label) for label in labels]
except InvalidDomainName:
return ''
if normalize_result:
labels = normalized_labels
# Get suffix length
suffix_length, rule = self.get_suffix_length_and_rule(normalized_labels, icann_only=icann_only)
if rule is None:
return ''
if not keep_unknown_suffix and rule is self._generic_rule:
return ''
if suffix_length < len(labels):
suffix_length += 1
elif only_if_registerable:
return ''
return '.'.join(reversed(labels[:suffix_length])) + tail
# The official Public Suffix List
PUBLIC_SUFFIX_LIST = PublicSuffixList.load(os.path.join(os.path.dirname(__file__), '..', 'public_suffix_list.dat'))
|
