bpo-19083: IDNA prefix should be case insensitive

Any capitalization of "xn--" should be acceptable for the ACE prefix
(see https://tools.ietf.org/html/rfc3490#section-5).

Co-Authored-By: Pepijn de Vos <pepijndevos@gmail.com>
This commit is contained in:
Zackery Spytz 2019-12-27 23:56:07 -07:00
parent 98f0f04b50
commit 8ba363238e
2 changed files with 10 additions and 3 deletions

View File

@ -88,7 +88,7 @@ def ToASCII(label):
raise UnicodeError("label empty or too long")
# Step 5: Check ACE prefix
if label.startswith(sace_prefix):
if label.lower().startswith(sace_prefix):
raise UnicodeError("Label starts with ACE prefix")
# Step 6: Encode with PUNYCODE
@ -121,7 +121,7 @@ def ToUnicode(label):
except UnicodeError:
raise UnicodeError("Invalid character in IDN label")
# Step 3: Check for ACE prefix
if not label.startswith(ace_prefix):
if not label.lower().startswith(ace_prefix):
return str(label, "ascii")
# Step 4: Remove ACE prefix
@ -194,7 +194,7 @@ class Codec(codecs.Codec):
# XXX obviously wrong, see #3232
input = bytes(input)
if ace_prefix not in input:
if ace_prefix not in input.lower():
# Fast path
try:
return input.decode('ascii'), len(input)

View File

@ -1524,6 +1524,13 @@ class IDNACodecTest(unittest.TestCase):
self.assertEqual(str(b"python.org.", "idna"), "python.org.")
self.assertEqual(str(b"xn--pythn-mua.org", "idna"), "pyth\xf6n.org")
self.assertEqual(str(b"xn--pythn-mua.org.", "idna"), "pyth\xf6n.org.")
self.assertEqual(str(b"XN--pythn-mua.org.", "idna"), "pyth\xf6n.org.")
self.assertEqual(str(b"xN--pythn-mua.org.", "idna"), "pyth\xf6n.org.")
self.assertEqual(str(b"Xn--pythn-mua.org.", "idna"), "pyth\xf6n.org.")
self.assertEqual(str(b"bugs.xn--pythn-mua.org.", "idna"),
"bugs.pyth\xf6n.org.")
self.assertEqual(str(b"bugs.XN--pythn-mua.org.", "idna"),
"bugs.pyth\xf6n.org.")
def test_builtin_encode(self):
self.assertEqual("python.org".encode("idna"), b"python.org")