The ssl module now can dump key material to a keylog file and trace TLS
protocol messages with a tracing callback. The default and stdlib
contexts also support SSLKEYLOGFILE env var.
The msg_callback and related enums are private members. The feature
is designed for internal debugging and not for end users.
Signed-off-by: Christian Heimes <christian@python.org>
Add a function to collect certificates from several certificate stores into one certificate collection store that is then enumerated. This ensures we load as many certificates as we can access.
Fix a NULL pointer deref in ssl module. The cert parser did not handle CRL
distribution points with empty DP or URI correctly. A malicious or buggy
certificate can result into segfault.
Signed-off-by: Christian Heimes <christian@python.org>
https://bugs.python.org/issue35746
Don't pass complex expressions but regular variables to Python
macros.
* _datetimemodule.c: split single large "if" into two "if"
in date_new(), time_new() and datetime_new().
* _pickle.c, load_extension(): flatten complex "if" expression into
more regular C code.
* _ssl.c: addbool() now uses a temporary bool_obj to only evaluate
the value once.
* weakrefobject.c: replace "Py_INCREF(result = proxy);"
with "result = proxy; Py_INCREF(result);"
Add SSLContext.post_handshake_auth and
SSLSocket.verify_client_post_handshake for TLS 1.3 post-handshake
authentication.
Signed-off-by: Christian Heimes <christian@python.org>q
https://bugs.python.org/issue34670
OpenSSL follows the convention that whenever you call a function, it
returns an error indicator value; and if this value is negative, then
you need to go look at the actual error code to see what happened.
Commit c6fd1c1c3a introduced a small mistake in
_ssl__SSLSocket_shutdown_impl: instead of checking whether the error
indicator was negative, it started checking whether the actual error
code was negative, and it turns out that the error codes are never
negative. So the effect was that 'unwrap()' lost the ability to raise
SSL errors.
https://bugs.python.org/issue34759
The documentation for CERT_NONE, CERT_OPTIONAL, and CERT_REQUIRED were
misleading and partly wrong. It fails to explain that OpenSSL behaves
differently in client and server mode. Also OpenSSL does validate the
cert chain everytime. With SSL_VERIFY_NONE a validation error is not
fatal in client mode and does not request a client cert in server mode.
Also discourage people from using CERT_OPTIONAL in client mode.
The ssl module now contains OP_NO_RENEGOTIATION constant, available with
OpenSSL 1.1.0h or 1.1.1.
Note, OpenSSL 1.1.0h hasn't been released yet.
Signed-off-by: Christian Heimes <christian@python.org>
Harden ssl module against LibreSSL CVE-2018-8970.
X509_VERIFY_PARAM_set1_host() is called with an explicit namelen. A new test
ensures that NULL bytes are not allowed.
Signed-off-by: Christian Heimes <christian@python.org>
LibreSSL 2.7 introduced OpenSSL 1.1.0 API. The ssl module now detects
LibreSSL 2.7 and only provides API shims for OpenSSL < 1.1.0 and
LibreSSL < 2.7.
Documentation updates and fixes for failing tests will be provided in
another patch set.
Signed-off-by: Christian Heimes <christian@python.org>
OpenSSL 1.1 has introduced a new API to set the minimum and maximum
supported protocol version. The API is easier to use than the old
OP_NO_TLS1 option flags, too.
Since OpenSSL has no call to set minimum version to highest supported,
the implementation emulate maximum_version = MINIMUM_SUPPORTED and
minimum_version = MAXIMUM_SUPPORTED by figuring out the minumum and
maximum supported version at compile time.
Signed-off-by: Christian Heimes <christian@python.org>
* bpo-32947: OpenSSL 1.1.1-pre1 / TLS 1.3 fixes
Misc fixes and workarounds for compatibility with OpenSSL 1.1.1-pre1 and
TLS 1.3 support. With OpenSSL 1.1.1, Python negotiates TLS 1.3 by
default. Some test cases only apply to TLS 1.2. Other tests currently
fail because the threaded or async test servers stop after failure.
I'm going to address these issues when OpenSSL 1.1.1 reaches beta.
OpenSSL 1.1.1 has added a new option OP_ENABLE_MIDDLEBOX_COMPAT for TLS
1.3. The feature is enabled by default for maximum compatibility with
broken middle boxes. Users should be able to disable the hack and CPython's test suite needs
it to verify default options.
Signed-off-by: Christian Heimes <christian@python.org>
The ssl module now detects missing NPN support in LibreSSL.
Co-Authored-By: Bernard Spil <brnrd@FreeBSD.org>
Signed-off-by: Christian Heimes <christian@python.org>
* The SSLSocket is no longer implemented on top of SSLObject to
avoid an extra level of indirection.
* Owner and session are now handled in the internal constructor.
* _ssl._SSLSocket now uses the same method names as SSLSocket and
SSLObject.
* Channel binding type check is now handled in C code. Channel binding
is always available.
The patch also changes the signature of SSLObject.__init__(). In my
opinion it's fine. A SSLObject is not a user-constructable object.
SSLContext.wrap_bio() is the only valid factory.
Previously, the ssl module stored international domain names (IDNs)
as U-labels. This is problematic for a number of reasons -- for
example, it made it impossible for users to use a different version
of IDNA than the one built into Python.
After this change, we always convert to A-labels as soon as possible,
and use them for all internal processing. In particular, server_hostname
attribute is now an A-label, and on the server side there's a new
sni_callback that receives the SNI servername as an A-label rather than
a U-label.
Until now Python used a hard coded white list of default TLS cipher
suites. The old approach has multiple downsides. OpenSSL's default
selection was completely overruled. Python did neither benefit from new
cipher suites (ChaCha20, TLS 1.3 suites) nor blacklisted cipher suites.
For example we used to re-enable 3DES.
Python now defaults to OpenSSL DEFAULT cipher suite selection and black
lists all unwanted ciphers. Downstream vendors can override the default
cipher list with --with-ssl-default-suites.
Signed-off-by: Christian Heimes <christian@python.org>
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>
Add https://www.gnu.org/software/autoconf-archive/ax_check_openssl.html
to auto-detect compiler flags, linker flags and libraries to compile
OpenSSL extensions. The M4 macro uses pkg-config and falls back to
manual detection.
Add autoconf magic to detect usable X509_VERIFY_PARAM_set1_host()
and related functions.
Refactor setup.py to use new config vars to compile _ssl and _hashlib
modules.
Signed-off-by: Christian Heimes <christian@python.org>
Cast Py_buffer.len (Py_ssize_t, signed) to size_t (unsigned) to
prevent the following warning:
Modules/_ssl.c:3089:21: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
The SSL module now raises SSLCertVerificationError when OpenSSL fails to
verify the peer's certificate. The exception contains more information about
the error.
Original patch by Chi Hsuan Yen
Signed-off-by: Christian Heimes <christian@python.org>
* bpo-29136: Add TLS 1.3 support
TLS 1.3 introduces a new, distinct set of cipher suites. The TLS 1.3
cipher suites don't overlap with cipher suites from TLS 1.2 and earlier.
Since Python sets its own set of permitted ciphers, TLS 1.3 handshake
will fail as soon as OpenSSL 1.1.1 is released. Let's enable the common
AES-GCM and ChaCha20 suites.
Additionally the flag OP_NO_TLSv1_3 is added. It defaults to 0 (no op) with
OpenSSL prior to 1.1.1. This allows applications to opt-out from TLS 1.3
now.
Signed-off-by: Christian Heimes <christian@python.org>
SSLObject.version() now correctly returns None when handshake over BIO has
not been performed yet.
Signed-off-by: Christian Heimes <christian@python.org>
The ssl and hashlib modules now call OPENSSL_add_all_algorithms_noconf() on
OpenSSL < 1.1.0. The function detects CPU features and enables optimizations
on some CPU architectures such as POWER8. Patch is based on research from
Gustavo Serra Scalet.
Signed-off-by: Christian Heimes <christian@python.org>
* Change NPN detection:
Version breakdown, support disabled (pre-patch/post-patch):
- pre-1.0.1: OPENSSL_NPN_NEGOTIATED will not be defined -> False/False
- 1.0.1 and 1.0.2: OPENSSL_NPN_NEGOTIATED will not be defined ->
False/False
- 1.1.0+: OPENSSL_NPN_NEGOTIATED will be defined and
OPENSSL_NO_NEXTPROTONEG will be defined -> True/False
Version breakdown support enabled (pre-patch/post-patch):
- pre-1.0.1: OPENSSL_NPN_NEGOTIATED will not be defined -> False/False
- 1.0.1 and 1.0.2: OPENSSL_NPN_NEGOTIATED will be defined and
OPENSSL_NO_NEXTPROTONEG will not be defined -> True/True
- 1.1.0+: OPENSSL_NPN_NEGOTIATED will be defined and
OPENSSL_NO_NEXTPROTONEG will not be defined -> True/True
* Refine NPN guard:
- If NPN is disabled, but ALPN is available we need our callback
- Make clinic's ssl behave the same way
This created a working ssl module for me, with NPN disabled and ALPN
enabled for OpenSSL 1.1.0f.
Concerns to address:
The initial commit for NPN support into OpenSSL [1], had the
OPENSSL_NPN_* variables defined inside the OPENSSL_NO_NEXTPROTONEG
guard. The question is if that ever made it into a release.
This would need an ugly hack, something like:
#if defined(OPENSSL_NO_NEXTPROTONEG) && \
!defined(OPENSSL_NPN_NEGOTIATED)
# define OPENSSL_NPN_UNSUPPORTED 0
# define OPENSSL_NPN_NEGOTIATED 1
# define OPENSSL_NPN_NO_OVERLAP 2
#endif
[1] https://github.com/openssl/openssl/commit/68b33cc5c7
Christian Heimes
Serhiy Storchaka
Jeroen Demeyer
Paul Monson
Inada Naoki
kctherookie
Zackery Spytz
Victor Stinner
Stéphane Wirtel
Nathaniel J. Smith
Steve Dower
Alexandru Ardelean
Ned Deily
Alex Gaynor
Semen Zhydenko
Victor Stinner
Antoine Pitrou
Melvyn Sopacua
INADA Naoki
Segev Finer