/usr/lib/python3.2/encodings/idna.py is in python3.2-minimal 3.2.3-0ubuntu3.8.
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 | # This module implements the RFCs 3490 (IDNA) and 3491 (Nameprep)
import stringprep, re, codecs
from unicodedata import ucd_3_2_0 as unicodedata
# IDNA section 3.1
dots = re.compile("[\u002E\u3002\uFF0E\uFF61]")
# IDNA section 5
ace_prefix = b"xn--"
sace_prefix = "xn--"
# This assumes query strings, so AllowUnassigned is true
def nameprep(label):
# Map
newlabel = []
for c in label:
if stringprep.in_table_b1(c):
# Map to nothing
continue
newlabel.append(stringprep.map_table_b2(c))
label = "".join(newlabel)
# Normalize
label = unicodedata.normalize("NFKC", label)
# Prohibit
for c in label:
if stringprep.in_table_c12(c) or \
stringprep.in_table_c22(c) or \
stringprep.in_table_c3(c) or \
stringprep.in_table_c4(c) or \
stringprep.in_table_c5(c) or \
stringprep.in_table_c6(c) or \
stringprep.in_table_c7(c) or \
stringprep.in_table_c8(c) or \
stringprep.in_table_c9(c):
raise UnicodeError("Invalid character %r" % c)
# Check bidi
RandAL = [stringprep.in_table_d1(x) for x in label]
for c in RandAL:
if c:
# There is a RandAL char in the string. Must perform further
# tests:
# 1) The characters in section 5.8 MUST be prohibited.
# This is table C.8, which was already checked
# 2) If a string contains any RandALCat character, the string
# MUST NOT contain any LCat character.
if any(stringprep.in_table_d2(x) for x in label):
raise UnicodeError("Violation of BIDI requirement 2")
# 3) If a string contains any RandALCat character, a
# RandALCat character MUST be the first character of the
# string, and a RandALCat character MUST be the last
# character of the string.
if not RandAL[0] or not RandAL[-1]:
raise UnicodeError("Violation of BIDI requirement 3")
return label
def ToASCII(label):
try:
# Step 1: try ASCII
label = label.encode("ascii")
except UnicodeError:
pass
else:
# Skip to step 3: UseSTD3ASCIIRules is false, so
# Skip to step 8.
if 0 < len(label) < 64:
return label
raise UnicodeError("label empty or too long")
# Step 2: nameprep
label = nameprep(label)
# Step 3: UseSTD3ASCIIRules is false
# Step 4: try ASCII
try:
label = label.encode("ascii")
except UnicodeError:
pass
else:
# Skip to step 8.
if 0 < len(label) < 64:
return label
raise UnicodeError("label empty or too long")
# Step 5: Check ACE prefix
if label.startswith(sace_prefix):
raise UnicodeError("Label starts with ACE prefix")
# Step 6: Encode with PUNYCODE
label = label.encode("punycode")
# Step 7: Prepend ACE prefix
label = ace_prefix + label
# Step 8: Check size
if 0 < len(label) < 64:
return label
raise UnicodeError("label empty or too long")
def ToUnicode(label):
# Step 1: Check for ASCII
if isinstance(label, bytes):
pure_ascii = True
else:
try:
label = label.encode("ascii")
pure_ascii = True
except UnicodeError:
pure_ascii = False
if not pure_ascii:
# Step 2: Perform nameprep
label = nameprep(label)
# It doesn't say this, but apparently, it should be ASCII now
try:
label = label.encode("ascii")
except UnicodeError:
raise UnicodeError("Invalid character in IDN label")
# Step 3: Check for ACE prefix
if not label.startswith(ace_prefix):
return str(label, "ascii")
# Step 4: Remove ACE prefix
label1 = label[len(ace_prefix):]
# Step 5: Decode using PUNYCODE
result = label1.decode("punycode")
# Step 6: Apply ToASCII
label2 = ToASCII(result)
# Step 7: Compare the result of step 6 with the one of step 3
# label2 will already be in lower case.
if str(label, "ascii").lower() != str(label2, "ascii"):
raise UnicodeError("IDNA does not round-trip", label, label2)
# Step 8: return the result of step 5
return result
### Codec APIs
class Codec(codecs.Codec):
def encode(self, input, errors='strict'):
if errors != 'strict':
# IDNA is quite clear that implementations must be strict
raise UnicodeError("unsupported error handling "+errors)
if not input:
return b'', 0
result = bytearray()
labels = dots.split(input)
if labels and not labels[-1]:
trailing_dot = b'.'
del labels[-1]
else:
trailing_dot = b''
for label in labels:
if result:
# Join with U+002E
result.extend(b'.')
result.extend(ToASCII(label))
return bytes(result+trailing_dot), len(input)
def decode(self, input, errors='strict'):
if errors != 'strict':
raise UnicodeError("Unsupported error handling "+errors)
if not input:
return "", 0
# IDNA allows decoding to operate on Unicode strings, too.
if not isinstance(input, bytes):
# XXX obviously wrong, see #3232
input = bytes(input)
labels = input.split(b".")
if labels and len(labels[-1]) == 0:
trailing_dot = '.'
del labels[-1]
else:
trailing_dot = ''
result = []
for label in labels:
result.append(ToUnicode(label))
return ".".join(result)+trailing_dot, len(input)
class IncrementalEncoder(codecs.BufferedIncrementalEncoder):
def _buffer_encode(self, input, errors, final):
if errors != 'strict':
# IDNA is quite clear that implementations must be strict
raise UnicodeError("unsupported error handling "+errors)
if not input:
return (b'', 0)
labels = dots.split(input)
trailing_dot = b''
if labels:
if not labels[-1]:
trailing_dot = b'.'
del labels[-1]
elif not final:
# Keep potentially unfinished label until the next call
del labels[-1]
if labels:
trailing_dot = b'.'
result = bytearray()
size = 0
for label in labels:
if size:
# Join with U+002E
result.extend(b'.')
size += 1
result.extend(ToASCII(label))
size += len(label)
result += trailing_dot
size += len(trailing_dot)
return (bytes(result), size)
class IncrementalDecoder(codecs.BufferedIncrementalDecoder):
def _buffer_decode(self, input, errors, final):
if errors != 'strict':
raise UnicodeError("Unsupported error handling "+errors)
if not input:
return ("", 0)
# IDNA allows decoding to operate on Unicode strings, too.
if isinstance(input, str):
labels = dots.split(input)
else:
# Must be ASCII string
input = str(input, "ascii")
labels = input.split(".")
trailing_dot = ''
if labels:
if not labels[-1]:
trailing_dot = '.'
del labels[-1]
elif not final:
# Keep potentially unfinished label until the next call
del labels[-1]
if labels:
trailing_dot = '.'
result = []
size = 0
for label in labels:
result.append(ToUnicode(label))
if size:
size += 1
size += len(label)
result = ".".join(result) + trailing_dot
size += len(trailing_dot)
return (result, size)
class StreamWriter(Codec,codecs.StreamWriter):
pass
class StreamReader(Codec,codecs.StreamReader):
pass
### encodings module API
def getregentry():
return codecs.CodecInfo(
name='idna',
encode=Codec().encode,
decode=Codec().decode,
incrementalencoder=IncrementalEncoder,
incrementaldecoder=IncrementalDecoder,
streamwriter=StreamWriter,
streamreader=StreamReader,
)
|