merge with 3.3

This commit is contained in:
Georg Brandl 2013-10-27 07:46:09 +01:00
commit b89b5df9c9
13 changed files with 191 additions and 38 deletions

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@ -169,8 +169,8 @@ The following exceptions are raised as appropriate:
A subclass of :exc:`HTTPException`. Raised if a server responds with a HTTP
status code that we don't understand.
The constants defined in this module are:
The constants defined in this module are:
.. data:: HTTP_PORT

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@ -286,10 +286,10 @@ Certificate handling
Verify that *cert* (in decoded format as returned by
:meth:`SSLSocket.getpeercert`) matches the given *hostname*. The rules
applied are those for checking the identity of HTTPS servers as outlined
in :rfc:`2818`, except that IP addresses are not currently supported.
In addition to HTTPS, this function should be suitable for checking the
identity of servers in various SSL-based protocols such as FTPS, IMAPS,
POPS and others.
in :rfc:`2818` and :rfc:`6125`, except that IP addresses are not currently
supported. In addition to HTTPS, this function should be suitable for
checking the identity of servers in various SSL-based protocols such as
FTPS, IMAPS, POPS and others.
:exc:`CertificateError` is raised on failure. On success, the function
returns nothing::
@ -304,6 +304,13 @@ Certificate handling
.. versionadded:: 3.2
.. versionchanged:: 3.3.3
The function now follows :rfc:`6125`, section 6.4.3 and does neither
match multiple wildcards (e.g. ``*.*.com`` or ``*a*.example.org``) nor
a wildcard inside an internationalized domain names (IDN) fragment.
IDN A-labels such as ``www*.xn--pthon-kva.org`` are still supported,
but ``x*.python.org`` no longer matches ``xn--tda.python.org``.
.. function:: cert_time_to_seconds(timestring)
Returns a floating-point value containing a normal seconds-after-the-epoch

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@ -214,6 +214,8 @@ MAXAMOUNT = 1048576
# maximal line length when calling readline().
_MAXLINE = 65536
_MAXHEADERS = 100
class HTTPMessage(email.message.Message):
# XXX The only usage of this method is in
@ -261,6 +263,8 @@ def parse_headers(fp, _class=HTTPMessage):
if len(line) > _MAXLINE:
raise LineTooLong("header line")
headers.append(line)
if len(headers) > _MAXHEADERS:
raise HTTPException("got more than %d headers" % _MAXHEADERS)
if line in (b'\r\n', b'\n', b''):
break
hstring = b''.join(headers).decode('iso-8859-1')

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@ -43,6 +43,15 @@ IMAP4_PORT = 143
IMAP4_SSL_PORT = 993
AllowedVersions = ('IMAP4REV1', 'IMAP4') # Most recent first
# Maximal line length when calling readline(). This is to prevent
# reading arbitrary length lines. RFC 3501 and 2060 (IMAP 4rev1)
# don't specify a line length. RFC 2683 however suggests limiting client
# command lines to 1000 octets and server command lines to 8000 octets.
# We have selected 10000 for some extra margin and since that is supposedly
# also what UW and Panda IMAP does.
_MAXLINE = 10000
# Commands
Commands = {
@ -256,7 +265,10 @@ class IMAP4:
def readline(self):
"""Read line from remote."""
return self.file.readline()
line = self.file.readline(_MAXLINE + 1)
if len(line) > _MAXLINE:
raise self.error("got more than %d bytes" % _MAXLINE)
return line
def send(self, data):

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@ -85,6 +85,13 @@ __all__ = ["NNTP",
"decode_header",
]
# maximal line length when calling readline(). This is to prevent
# reading arbitrary lenght lines. RFC 3977 limits NNTP line length to
# 512 characters, including CRLF. We have selected 2048 just to be on
# the safe side.
_MAXLINE = 2048
# Exceptions raised when an error or invalid response is received
class NNTPError(Exception):
"""Base class for all nntplib exceptions"""
@ -424,7 +431,9 @@ class _NNTPBase:
"""Internal: return one line from the server, stripping _CRLF.
Raise EOFError if the connection is closed.
Returns a bytes object."""
line = self.file.readline()
line = self.file.readline(_MAXLINE +1)
if len(line) > _MAXLINE:
raise NNTPDataError('line too long')
if self.debugging > 1:
print('*get*', repr(line))
if not line: raise EOFError

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@ -40,6 +40,12 @@ CR = b'\r'
LF = b'\n'
CRLF = CR+LF
# maximal line length when calling readline(). This is to prevent
# reading arbitrary lenght lines. RFC 1939 limits POP3 line length to
# 512 characters, including CRLF. We have selected 2048 just to be on
# the safe side.
_MAXLINE = 2048
class POP3:
@ -118,7 +124,10 @@ class POP3:
# Raise error_proto('-ERR EOF') if the connection is closed.
def _getline(self):
line = self.file.readline()
line = self.file.readline(_MAXLINE + 1)
if len(line) > _MAXLINE:
raise error_proto('line too long')
if self._debugging > 1: print('*get*', repr(line))
if not line: raise error_proto('-ERR EOF')
octets = len(line)

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@ -166,31 +166,59 @@ class CertificateError(ValueError):
pass
def _dnsname_to_pat(dn, max_wildcards=1):
def _dnsname_match(dn, hostname, max_wildcards=1):
"""Matching according to RFC 6125, section 6.4.3
http://tools.ietf.org/html/rfc6125#section-6.4.3
"""
pats = []
for frag in dn.split(r'.'):
if frag.count('*') > max_wildcards:
# Issue #17980: avoid denials of service by refusing more
# than one wildcard per fragment. A survey of established
# policy among SSL implementations showed it to be a
# reasonable choice.
raise CertificateError(
"too many wildcards in certificate DNS name: " + repr(dn))
if frag == '*':
# When '*' is a fragment by itself, it matches a non-empty dotless
# fragment.
pats.append('[^.]+')
else:
# Otherwise, '*' matches any dotless fragment.
frag = re.escape(frag)
pats.append(frag.replace(r'\*', '[^.]*'))
return re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE)
if not dn:
return False
leftmost, *remainder = dn.split(r'.')
wildcards = leftmost.count('*')
if wildcards > max_wildcards:
# Issue #17980: avoid denials of service by refusing more
# than one wildcard per fragment. A survery of established
# policy among SSL implementations showed it to be a
# reasonable choice.
raise CertificateError(
"too many wildcards in certificate DNS name: " + repr(dn))
# speed up common case w/o wildcards
if not wildcards:
return dn.lower() == hostname.lower()
# RFC 6125, section 6.4.3, subitem 1.
# The client SHOULD NOT attempt to match a presented identifier in which
# the wildcard character comprises a label other than the left-most label.
if leftmost == '*':
# When '*' is a fragment by itself, it matches a non-empty dotless
# fragment.
pats.append('[^.]+')
elif leftmost.startswith('xn--') or hostname.startswith('xn--'):
# RFC 6125, section 6.4.3, subitem 3.
# The client SHOULD NOT attempt to match a presented identifier
# where the wildcard character is embedded within an A-label or
# U-label of an internationalized domain name.
pats.append(re.escape(leftmost))
else:
# Otherwise, '*' matches any dotless string, e.g. www*
pats.append(re.escape(leftmost).replace(r'\*', '[^.]*'))
# add the remaining fragments, ignore any wildcards
for frag in remainder:
pats.append(re.escape(frag))
pat = re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE)
return pat.match(hostname)
def match_hostname(cert, hostname):
"""Verify that *cert* (in decoded format as returned by
SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 rules
are mostly followed, but IP addresses are not accepted for *hostname*.
SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 and RFC 6125
rules are followed, but IP addresses are not accepted for *hostname*.
CertificateError is raised on failure. On success, the function
returns nothing.
@ -201,7 +229,7 @@ def match_hostname(cert, hostname):
san = cert.get('subjectAltName', ())
for key, value in san:
if key == 'DNS':
if _dnsname_to_pat(value).match(hostname):
if _dnsname_match(value, hostname):
return
dnsnames.append(value)
if not dnsnames:
@ -212,7 +240,7 @@ def match_hostname(cert, hostname):
# XXX according to RFC 2818, the most specific Common Name
# must be used.
if key == 'commonName':
if _dnsname_to_pat(value).match(hostname):
if _dnsname_match(value, hostname):
return
dnsnames.append(value)
if len(dnsnames) > 1:

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@ -347,6 +347,15 @@ class BasicTest(TestCase):
self.fail("Did not expect response from HEAD request")
self.assertEqual(bytes(b), b'\x00'*5)
def test_too_many_headers(self):
headers = '\r\n'.join('Header%d: foo' % i
for i in range(client._MAXHEADERS + 1)) + '\r\n'
text = ('HTTP/1.1 200 OK\r\n' + headers)
s = FakeSocket(text)
r = client.HTTPResponse(s)
self.assertRaisesRegex(client.HTTPException,
r"got more than \d+ headers", r.begin)
def test_send_file(self):
expected = (b'GET /foo HTTP/1.1\r\nHost: example.com\r\n'
b'Accept-Encoding: identity\r\nContent-Length:')

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@ -325,6 +325,17 @@ class BaseThreadedNetworkedTests(unittest.TestCase):
self.assertEqual(ret, "OK")
def test_linetoolong(self):
class TooLongHandler(SimpleIMAPHandler):
def handle(self):
# Send a very long response line
self.wfile.write(b'* OK ' + imaplib._MAXLINE*b'x' + b'\r\n')
with self.reaped_server(TooLongHandler) as server:
self.assertRaises(imaplib.IMAP4.error,
self.imap_class, *server.server_address)
class ThreadedNetworkedTests(BaseThreadedNetworkedTests):
server_class = socketserver.TCPServer

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@ -584,6 +584,11 @@ class NNTPv1Handler:
<a4929a40-6328-491a-aaaf-cb79ed7309a2@q2g2000vbk.googlegroups.com>
<f30c0419-f549-4218-848f-d7d0131da931@y3g2000vbm.googlegroups.com>
.""")
elif (group == 'comp.lang.python' and
date_str in ('20100101', '100101') and
time_str == '090000'):
self.push_lit('too long line' * 3000 +
'\n.')
else:
self.push_lit("""\
230 An empty list of newsarticles follows
@ -1179,6 +1184,11 @@ class NNTPv1v2TestsMixin:
self.assertEqual(cm.exception.response,
"435 Article not wanted")
def test_too_long_lines(self):
dt = datetime.datetime(2010, 1, 1, 9, 0, 0)
self.assertRaises(nntplib.NNTPDataError,
self.server.newnews, "comp.lang.python", dt)
class NNTPv1Tests(NNTPv1v2TestsMixin, MockedNNTPTestsMixin, unittest.TestCase):
"""Tests an NNTP v1 server (no capabilities)."""

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@ -94,7 +94,7 @@ class DummyPOP3Handler(asynchat.async_chat):
def cmd_list(self, arg):
if arg:
self.push('+OK %s %s' %(arg, arg))
self.push('+OK %s %s' % (arg, arg))
else:
self.push('+OK')
asynchat.async_chat.push(self, LIST_RESP)
@ -278,6 +278,10 @@ class TestPOP3Class(TestCase):
foo = self.client.retr('foo')
self.assertEqual(foo, expected)
def test_too_long_lines(self):
self.assertRaises(poplib.error_proto, self.client._shortcmd,
'echo +%s' % ((poplib._MAXLINE + 10) * 'a'))
def test_dele(self):
self.assertOK(self.client.dele('foo'))
@ -400,7 +404,13 @@ if SUPPORTS_SSL:
def tearDown(self):
if self.client.file is not None and self.client.sock is not None:
self.client.quit()
try:
self.client.quit()
except poplib.error_proto:
# happens in the test_too_long_lines case; the overlong
# response will be treated as response to QUIT and raise
# this exception
pass
self.server.stop()
def test_stls(self):

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@ -358,11 +358,7 @@ class BasicSocketTests(unittest.TestCase):
fail(cert, 'Xa.com')
fail(cert, '.a.com')
cert = {'subject': ((('commonName', 'a.*.com'),),)}
ok(cert, 'a.foo.com')
fail(cert, 'a..com')
fail(cert, 'a.com')
# only match one left-most wildcard
cert = {'subject': ((('commonName', 'f*.com'),),)}
ok(cert, 'foo.com')
ok(cert, 'f.com')
@ -377,6 +373,36 @@ class BasicSocketTests(unittest.TestCase):
fail(cert, 'example.org')
fail(cert, 'null.python.org')
# error cases with wildcards
cert = {'subject': ((('commonName', '*.*.a.com'),),)}
fail(cert, 'bar.foo.a.com')
fail(cert, 'a.com')
fail(cert, 'Xa.com')
fail(cert, '.a.com')
cert = {'subject': ((('commonName', 'a.*.com'),),)}
fail(cert, 'a.foo.com')
fail(cert, 'a..com')
fail(cert, 'a.com')
# wildcard doesn't match IDNA prefix 'xn--'
idna = 'püthon.python.org'.encode("idna").decode("ascii")
cert = {'subject': ((('commonName', idna),),)}
ok(cert, idna)
cert = {'subject': ((('commonName', 'x*.python.org'),),)}
fail(cert, idna)
cert = {'subject': ((('commonName', 'xn--p*.python.org'),),)}
fail(cert, idna)
# wildcard in first fragment and IDNA A-labels in sequent fragments
# are supported.
idna = 'www*.pythön.org'.encode("idna").decode("ascii")
cert = {'subject': ((('commonName', idna),),)}
ok(cert, 'www.pythön.org'.encode("idna").decode("ascii"))
ok(cert, 'www1.pythön.org'.encode("idna").decode("ascii"))
fail(cert, 'ftp.pythön.org'.encode("idna").decode("ascii"))
fail(cert, 'pythön.org'.encode("idna").decode("ascii"))
# Slightly fake real-world example
cert = {'notAfter': 'Jun 26 21:41:46 2011 GMT',
'subject': ((('commonName', 'linuxfrz.org'),),),
@ -437,7 +463,7 @@ class BasicSocketTests(unittest.TestCase):
cert = {'subject': ((('commonName', 'a*b.com'),),)}
ok(cert, 'axxb.com')
cert = {'subject': ((('commonName', 'a*b.co*'),),)}
ok(cert, 'axxb.com')
fail(cert, 'axxb.com')
cert = {'subject': ((('commonName', 'a*b*.com'),),)}
with self.assertRaises(ssl.CertificateError) as cm:
ssl.match_hostname(cert, 'axxbxxc.com')

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@ -23,6 +23,24 @@ Library
- Issue #19329: Optimized compiling charsets in regular expressions.
- Issue #16037: HTTPMessage.readheaders() raises an HTTPException when more than
100 headers are read. Adapted from patch by Jyrki Pulliainen.
- Issue #16040: CVE-2013-1752: nntplib: Limit maximum line lengths to 2048 to
prevent readline() calls from consuming too much memory. Patch by Jyrki
Pulliainen.
- Issue #16041: CVE-2013-1752: poplib: Limit maximum line lengths to 2048 to
prevent readline() calls from consuming too much memory. Patch by Jyrki
Pulliainen.
- Issue #17997: Change behavior of ``ssl.match_hostname()`` to follow RFC 6125,
for security reasons. It now doesn't match multiple wildcards nor wildcards
inside IDN fragments.
- Issue #16039: CVE-2013-1752: Change use of readline in imaplib module to limit
line length. Patch by Emil Lind.
- Issue #19330: the unnecessary wrapper functions have been removed from the
implementations of the new contextlib.redirect_stdout and
contextlib.suppress context managers, which also ensures they provide