/usr/lib/python3/dist-packages/provisioningserver/utils/isc.py is in python3-maas-provisioningserver 2.0.0~beta3+bzr4941-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 | # Copyright (c) 2015-2016 Canonical Ltd.
# Copyright (c) 2009, Purdue University.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# Redistributions of source code must retain the above copyright notice, this
# list of conditions and the following disclaimer.
#
# Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# Neither the name of the Purdue University nor the names of its contributors
# may be used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
from collections import OrderedDict
__all__ = [
'ISCParseException',
'make_isc_string',
'parse_isc_string',
'read_isc_file',
]
import copy
class ISCParseException(Exception):
"""Thrown when an ISC string cannot be parsed."""
def _clip(char_list):
"""Clips char_list to individual stanza.
Inputs:
char_list: partial of char_list from _parse_tokens
Outputs:
tuple: (int: skip to char list index, list: shortened char_list)
"""
assert char_list[0] == '{'
char_list.pop(0)
skip = 0
for index, item in enumerate(char_list):
if item == '{':
skip += 1
elif item == '}' and skip == 0:
return index, char_list[:index]
elif item == '}':
skip -= 1
raise ISCParseException("Invalid brackets.")
def _parse_tokens(char_list):
"""Parses exploded isc named.conf portions.
Inputs:
char_list: List of isc file parts
Outputs:
dict: fragment or full isc file dict
Recursive dictionary of isc file, dict values can be of 3 types,
dict, string and bool. Boolean values are always true. Booleans are false
if key is absent. Booleans represent situations in isc files such as:
acl "registered" { 10.1.0/32; 10.1.1:/32;}}
Example:
{'stanza1 "new"': 'test_info', 'stanza1 "embedded"': {'acl "registered"':
{'10.1.0/32': True, '10.1.1/32': True}}}
"""
index = 0
dictionary_fragment = OrderedDict()
new_char_list = copy.deepcopy(char_list)
if type(new_char_list) == str:
return new_char_list
if type(new_char_list) == OrderedDict:
return new_char_list
last_open = None
continuous_line = False
temp_list = []
# Prevent "may be referenced before assignment" error
key = None
while index < len(new_char_list):
if new_char_list[index] == '{':
last_open = index
if new_char_list[index] == ';' and continuous_line:
dictionary_fragment = temp_list
temp_list = []
continuous_line = False
if new_char_list[index] == ';':
continuous_line = False
if (len(new_char_list) > index + 1 and
new_char_list[index] == '}' and
new_char_list[index + 1] != ';'):
skip, value = _clip(new_char_list[last_open:])
temp_list.append({key: copy.deepcopy(_parse_tokens(value))})
continuous_line = True
if len(new_char_list) > index + 1 and new_char_list[index + 1] == '{':
# assert key is not None
key = new_char_list.pop(index)
skip, dict_value = _clip(new_char_list[index:])
if continuous_line:
temp_list.append(
{key: copy.deepcopy(_parse_tokens(dict_value))})
else:
dictionary_fragment[key] = copy.deepcopy(
_parse_tokens(dict_value))
index += skip
else:
if len(new_char_list[
index].split()) == 1 and '{' not in new_char_list:
for item in new_char_list:
if item in [';']:
continue
dictionary_fragment[item] = True
# If there are more than 1 'keywords' at new_char_list[index]
# ex - "recursion no;"
elif len(new_char_list[index].split()) >= 2:
if type(dictionary_fragment) == list:
raise ISCParseException("Syntax error")
dictionary_fragment[
new_char_list[index].split()[0]] = (
' '.join(new_char_list[index].split()[1:]))
index += 1
# If there is just 1 'keyword' at new_char_list[index]
# ex "recursion;" (not a valid option, but for example's sake it's
# fine)
elif new_char_list[index] not in ['{', ';', '}']:
key = new_char_list[index]
if type(dictionary_fragment) == list:
raise ISCParseException("Syntax error")
dictionary_fragment[key] = ''
index += 1
index += 1
return dictionary_fragment
def _scrub_comments(isc_string):
"""Clears comments from an isc file
Inputs:
isc_string: string of isc file
Outputs:
string: string of scrubbed isc file
"""
isc_list = []
if isc_string is None:
return ''
expanded_comment = False
for line in isc_string.split('\n'):
no_comment_line = ""
# Vet out any inline comments
if '/*' in line.strip():
try:
striped_line = line.strip()
chars = enumerate(striped_line)
while True:
i, c = next(chars)
try:
if c == '/' and striped_line[i + 1] == '*':
expanded_comment = True
next(chars) # Skip '*'
continue
elif c == '*' and striped_line[i + 1] == '/':
expanded_comment = False
next(chars) # Skip '/'
continue
except IndexError:
continue # We are at the end of the line
if expanded_comment:
continue
else:
no_comment_line += c
except StopIteration:
if no_comment_line:
isc_list.append(no_comment_line)
continue
if expanded_comment:
if '*/' in line.strip():
expanded_comment = False
isc_list.append(line.split('*/')[-1])
continue
else:
continue
if line.strip().startswith(('#', '//')):
continue
else:
isc_list.append(line.split('#')[0].split('//')[0].strip())
return '\n'.join(isc_list)
def _explode(isc_string):
"""Explodes isc file into relevant tokens.
Inputs:
isc_string: String of isc file
Outputs:
list: list of isc file tokens delimited by brackets and semicolons
['stanza1 "new"', '{', 'test_info', ';', '}']
"""
str_array = []
temp_string = []
for char in isc_string:
if char in ['\n']:
continue
if char in ['{', '}', ';']:
if ''.join(temp_string).strip() == '':
str_array.append(char)
else:
str_array.append(''.join(temp_string).strip())
str_array.append(char)
temp_string = []
else:
temp_string.append(char)
return str_array
def parse_isc_string(isc_string):
"""Makes a dictionary from an ISC file string
Inputs:
isc_string: string of isc file
Outputs:
dict: dictionary of ISC file representation
"""
return _parse_tokens(_explode(_scrub_comments(isc_string)))
def make_isc_string(isc_dict, terminate=True):
"""Outputs an isc formatted file string from a dict
Inputs:
isc_dict: a recursive dictionary to be turned into an isc file
(from ParseTokens)
Outputs:
str: string of isc file without indentation
"""
if terminate:
terminator = ';'
else:
terminator = ''
if type(isc_dict) == str:
return isc_dict
isc_list = []
for option in isc_dict:
if type(isc_dict[option]) == bool:
isc_list.append('%s%s' % (option, terminator))
elif (type(isc_dict[option]) == str or
type(isc_dict[option]) == str):
isc_list.append('%s %s%s' % (option, isc_dict[option], terminator))
elif type(isc_dict[option]) == list:
new_list = []
for item in isc_dict[option]:
new_list.append(make_isc_string(item, terminate=False))
new_list[-1] = '%s%s' % (new_list[-1], terminator)
isc_list.append(
'%s { %s }%s' % (option, ' '.join(new_list), terminator))
elif (type(isc_dict[option]) == OrderedDict or
type(isc_dict[option]) == dict):
isc_list.append('%s { %s }%s' % (
option, make_isc_string(isc_dict[option]), terminator))
return '\n'.join(isc_list)
def read_isc_file(isc_file):
"""Given the specified filename, parses it to create a dictionary.
:param:isc_file: the filename to read
:return:dict: dictionary of ISC file representation
"""
with open(isc_file, "r", encoding="ascii") as f:
return parse_isc_string(f.read())
|