source: mod_gnutls/CHANGELOG

** Version 0.12.1 (2023-02-23)

- Security fix (CVE-2023-25824): Remove an infinite loop in blocking
  read on transport timeout. Mod_gnutls versions from 0.9.0 to 0.12.0
  (including) did not properly fail blocking read operations on TLS
  connections when the transport hit timeouts. Instead it entered an
  endless loop retrying the read operation, consuming CPU
  resources. This could be exploited for denial of service attacks. If
  trace level logging was enabled, it would also produce an excessive
  amount of log output during the loop, consuming disk space.

- Replace obsolete Autoconf macros. Generating ./configure now
  requires Autoconf 2.69 (present in Debian Bullseye).

** Version 0.12.0 (2021-08-14)

- Three fixes that make mod_gnutls compatible with the Let's Encrypt
  OCSP responder for OCSP stapling:

  1. Support OCSP responses that are signed directly with the private
     key of the CA and do not embed a signer certificate.

  2. If the path part of OCSP URI provided in the certificate is
     empty, use "/".

  3. Use SHA1 for issuer name hash and issuer key hash in OCSP
     requests. Support for that is required by RFC 5019 and referenced
     in CAB Forum Baseline Requirements, too. This particular hash
     doesn't need to be cryptographically secure.

- Remove insecure algorithms that are still included in the GnuTLS
  priority set "NORMAL" from the default priorities: plain RSA key
  exchange, TLS 1.0, TLS 1.1

- Fix virtual host references when retrieving OCSP responses for
  stapling.

- Share server instances for tests where reasonably possible with the
  same server configuration. Starting/stopping server instances is the
  slowest part of the tests, so this is a nice performance
  improvement. The Automake test harness now reports fewer tests, but
  some include a lot more client connections and requests to keep
  coverage at least as good as before.

- Various improvements to tests and logging infrastructure.

** Version 0.11.0 (2020-06-27)

- Change default for GnuTLSOCSPCheckNonce to "off", and send OCSP
  nonces only if it has been enabled. The reason for this change is
  that in practice most public CAs do not support OCSP nonces, which
  is permitted by both RFC 6960 and the CA/Browser Forum baseline
  requirements (as of version 1.6.9). In this situation enforcing
  correct nonces by default makes the automatic OCSP stapling support
  mostly useless.

- Add a test for correct nonce handling with "GnuTLSOCSPCheckNonce
  on", thanks to Krista Karppinen for that and a rewrite of the OCSP
  responder script in Python!

- Support session resumption using session tickets for proxy
  connections (TLS 1.3 connections only). Requires a suitable
  GnuTLSCache configuration.

- Disable session tickets by default. The GnuTLS built-in key rotation
  for session tickets never actually changes the primary key, just
  derives keys from it, so it does not provide forward secrecy in case
  an attacker learns the primary key (by gaining access to server
  RAM). A reload of the server is enough to generate a new key, so
  consider enabling session tickets and reloading the server every few
  hours, at least until a forward-secret rotation can be implemented.

- Fix a bug that mostly prevented searching ServerAliases when
  selecting the virtual host from SNI.

- Add ./configure option to disable building PDF documentation

- Deprecate SRP and disable it by default.

- Add support for building coverage reports using clang's source-based
  code coverage.

- Make ./configure check if both [::1] and 127.0.0.1 are available,
  disable either if not. This makes the build work out-of-the-box in
  Docker containers, which by default use IPv4 only.

** Version 0.10.0 (2020-02-03)

- Added support for stapling multiple OCSP responses (TLS 1.3
  only). mod_gnutls will staple for as many consecutive certificates
  in the certificate chain as possible.

- Added support for TLS 1.3 post-handshake authentication, used if TLS
  client authentication is required only for some resources on the
  server. Rehandshake (for older TLS versions) is not supported, the
  existing but broken code has been removed.

- The test infrastructure has been mostly rewritten in Python, note
  the new dependencies (Python 3, Pyyaml). Tests can run multiple TLS
  connections and HTTP(S) requests as well as custom hooks now, see
  test/README.md for details.

- Server certificates are checked for the must-staple TLS feature
  extension, stapling must be enabled if it is present.

- Compatibility fix for GnuTLS 3.6.11 in the test suite: Handle
  peer certificate type in TLS session information strings.

- The test system will automatically detect if it needs to load
  critical modules (e.g. mod_logio) that are built-in with the Debian
  packages. This makes the tests work on Fedora without modifications,
  and likely on similar distributions too.

- Tests can optionally run with Valgrind for the primary HTTPD
  instance by running ./configure with --enable-valgrind-test, see
  test/README.md for details.

- Known issue: When using MSVA client certificate validation the
  Valgrind tests indicate memory leaks from libcurl, which is used by
  libmsv to send requests to the MSVA. For details see the bug report:
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=950359

** Version 0.9.1 (2019-11-29)
- Fix possible segfault (NULL pointer dereference) on failed TLS
  handshake. Calling ssl_var_lookup() after a failed handshake could
  lead to GnuTLS session information functions being called on a NULL
  session pointer, leading to segfault.
- Remove URLs from expected error responses in the test suite. Apache
  HTTPD removed request URLs from canned error messages to prevent
  misleading text/links being displayed via crafted links
  (CVE-2019-10092). Adjust the expected error responses in our tests
  so they can pass again.
- Test suite: Ignore "Content-Length" header of responses. Thanks to
  Krista Karppinen!
- Add a section about module dependencies on socache to the handbook
- Restructure the manpage build and move it to section 5 (config
  files)
- Test suite: Restructure certificate directories

** Version 0.9.0 (2019-01-23)
- Security fix: Refuse to send or receive any data over a failed TLS
  connection (commit 72b669eae8c45dda1850e8e5b30a97c918357b51). The
  previous behavior could lead to requests on reverse proxy TLS
  connections being sent in plain text, and might have allowed faking
  requests in plain text.
- Security fix: Reject HTTP requests if they try to access virtual
  hosts that do not match their TLS connections (commit
  de3fad3c12f53cdbf082ad675e4b10f521a02811). Additionally check if SNI
  and Host header match. Thanks to Krista Karppinen for contributing
  tests!
- OCSP stapling is now enabled by default, if possible. OCSP responses
  are updated regularly and stored in a cache separate from the
  session cache. The OCSP cache uses mod_socache_shmcb by default
  (if the module is loaded, no other configuration required).
- Session tickets are now enabled by default if using GnuTLS 3.6.4 or
  newer. GnuTLS 3.6.4 introduced automatic rotation for the used key,
  and TLS 1.3 takes care of other reasons not to use tickets while
  requiring them for session resumption. Note that there is currently
  no mechanism to synchronize ticket keys across a cluster of servers.
- The internal cache implementation has been replaced with
  mod_socache. Users may need to update their GnuTLSCache settings and
  load the appropriate socache modules.
- ALPN (required for HTTP/2) now works correctly with different
  "Protocols" directives between virtual hosts if building with GnuTLS
  3.6.3 or newer. Older versions require identical "Protocols"
  directives for overlapping virtual hosts. Thanks to Vincent Tamet
  for the bug report!
- ALPN is now supported for proxy connections, making HTTP/2 proxy
  connections using mod_proxy_http2 possible.
- GnuTLSPriorities is optional now and defaults to "NORMAL" if
  missing. The same applies to GnuTLSProxyPriorities (if TLS proxy is
  enabled).
- The manual is now built as a manual page, too, if pandoc is
  available.
- OpenPGP support has been removed.
- Don't require pem2openpgp for tests when building without MSVA
  support.

** Version 0.8.4 (2018-04-13)
- Support Apache HTTPD 2.4.33 API for proxy TLS connections
- Support TLS for HTTP/2 connections with mod_http2
- Fix configuration of OCSP stapling callback

** Version 0.8.3 (2017-10-20)
- Use GnuTLS' default DH parameters by default
- Handle long Server Name Indication data and gracefully ignore
  unknown SNI types
- Send SNI for proxy connections
- Deprecate OpenPGP support like GnuTLS did (will be removed
  completely in a future release)
- Do not announce session ticket support for proxy connections
- Minor documentation updates (SSL_CLIENT_I_DN, reference for SNI)
- Test suite: Simplify handling of proxy backend servers and OCSP
  responders
- Test suite: stability/compatibility fixes

** Version 0.8.2 (2017-01-08)
- Test suite: Ensure CRLF line ends in HTTP headers
- Test suite, gen_ocsp_index.c: Handle serial as fixed order byte array

** Version 0.8.1 (2016-12-20)
- Bugfix: Use APR_SIZE_T_FMT for portable apr_size_t formatting

** Version 0.8.0 (2016-12-11)
- New: Support for OCSP stapling
- Bugfix: Access to DBM cache is locked using global mutex
  "gnutls-cache"
- Bugfix: GnuTLSSessionTickets is now disabled by default as described
  in the handbook
- Fixed memory leak while checking proxy backend certificate
- Fixed memory leaks in post_config
- Safely delete session ticket key (requires GnuTLS >= 3.4)
- Improved error handling in post_config hook
- Various handbook updates
- Internal API documentation can be generated using Doxygen
- Unused code has been removed (conditionals for GnuTLS 2.x and Apache
  versions before 2.2, internal Lua bytecode structure last used in
  2011).
- Test suite: Fixed locking for access to the PGP keyring of the test
  certificate authority
- mod_gnutls can be built using Clang (unsupported)

** Version 0.7.5 (2016-05-28)
- Sunil Mohan Adapa reported retry loops during session shutdown in
  cleanup_gnutls_session() due to gnutls_bye() incorrectly returning
  GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN. Setting the GnuTLS session
  errno in mgs_transport_write() fixes the problem.
- Import Daniel Kahn Gillmor's patches for GnuPG v2 support from the
  Debian package.
- Build system improvements that allow VPATH builds and get "make
  distcheck" to work

** Version 0.7.4 (2016-04-13)
- Support SoftHSM 2 for PKCS #11 testing
- Increase verbosity of test logs

** Version 0.7.3 (2016-01-12)
- Update test suite for compatibility with GnuTLS 3.4, which has
  stricter key usage checks and priorities than 3.3.
- Write non-HTML output to mod_status reports if AP_STATUS_SHORT is
  set (mod_status sets it for requests with the "auto" parameter, e.g.
  https://localhost/server-status?auto).
- Register "ssl_is_https" function so the special mod_rewrite variable
  %{HTTPS} works correctly with mod_gnutls. The new test case for this
  requires Wget or curl. Fixes Debian bug #514005.
- Test suite servers listen on IPv4 *and* IPv6 loopback addresses by
  default (other addresses configurable), which should fix failures
  due to localhost randomly resolving to either on some distributions.
- Isolate tests using network namespaces, if possible. This avoids
  port conflicts with other test cases (so they can run in parallel)
  and host services.
- Support for local Apache drop-in config files in the test suite
  (e.g. to load additional modules needed on Fedora).
- Try to use markdown to build HTML documentation if pandoc is not
  available.
- Disable use of flock if it is unavailable or does not support
  timeouts (the latter caused the build to fail on Debian Hurd).
- New test: Disable TLS 1.0 (regression test for Debian bug #754960).

** Version 0.7.2 (2015-11-21)
- Bugfix: Non-blocking reads in the input filter could lead to a busy
  wait in the gnutls_io_input_read function, causing high load on
  Keep-Alive connections waiting for data, until either more data
  could be received or the connection was closed. The fix is to pass
  EAGAIN/EINTR results up to the input filter so they can be handled
  properly.
- Close TLS session if the input filter receives EOF (mostly relevant
  for proper termination of proxy connections).
- Remove dependency on APR Memcache, which is replaced by the newer
  version included in the APR Utility Library (libaprutil).
- Remove dependency on bc. It was used for floating point arithmetic
  in the test suite, the calculations have been changed to use
  integers and pure bash code.

** Version 0.7.1 (2015-10-18)
- Improved handling of PKCS #11 modules: mod_gnutls now loads either
  modules specified using GnuTLSP11Module, or the system defaults, but
  not both. Thanks to Nikos Mavrogiannopoulos for the report and
  initial patch!
- Initialize variables to safe defaults during client certificate
  verification. Certain error code paths did not set them, but they
  should never be hit due to config validation. This adds another line
  of defense.
- Enable C99 support via autoconf
- Test suite improvements. Most importantly, automake now handles
  environment setup without any external make calls. Rules to build
  the certificates are included from the old test makefile. Note that
  the dependency on GNU make is not new (the test makefile always used
  GNU make syntax), it just wasn't listed explicitly.

** Version 0.7 (2015-07-12)
- Security fix for TLS client authentication (CVE-2015-2091)
- Bug fixes that enable support for reverse proxy operation
- Various test suite improvements. Tests are configured through autoconf,
  so the test suite now works for builds without Monkeysphere support.
- Add support for TLS connections to back end servers when operating as a
  reverse proxy (X.509 authentication only at the moment).
- PKCS #11 support for server keys and certificates
- Use strict compiler arguments by default (-Wall -Werror -Wextra)
- Allow limiting the size of certificates exported as SSL_SERVER_CERT
  and SSL_CLIENT_CERT through the GnuTLSExportCertificates directive

** Version 0.6 (2014-02-17)
- Generating DH Params instead of using static ones.
- Now considering ServerAlias Directives.
- Major Legacy Code Cleanup.
- html and pdf and manual documentation generated from markdown sources
- support monkeysphere validation agent (MSVA) client-certificate verification
- wider test suite
- GnuTLSExportCertificates off by default

** Version 0.5.10 (2011-07-12)
- Patched a bug responsible for excessive memory consumption by mod_gnutls.
- Support for proxying from SSL to plain HTTP was added (ie. proxy termination).

** Version 0.5.9 (2010-09-24)
- GnuTLSCache none is now an allowed option.
- Corrected behavior in Keep-Alive connections (do not
  terminate the connection prematurely)
- The GnuTLSCache variable now can be given the specific
  option "gdbm" instead of "dbm". "dbm" will use the berkeley
  db type of libapr while gdbm will force gdbm to be used.
  sdbm is no longer being used due to serious limitations.

** Version 0.5.8 (2010-08-18)
- Session tickets are enabled by default.
- Fixes some segmentation faults noticed in some
  configurations.

** Version 0.5.7 (2010-07-01)
- Force usage of SDBM. For some reason the default in
  my system had issues after reaching a limit of entries.
  SDBM seems stable so force it.
- Optimizations in session caching.
- Added support for session tickets. This allows a
  server to avoid using a session cache and still support
  session resumption. This is at the cost of transporting
  session data during handshake. New option
  GnuTLSSessionTickets [on|off]
- Depend on gnutls 2.10.0 to force support for safe
  renegotiation.

** Version 0.5.6 (2010-03-24)
- Corrected issue with firefox and long POST data (by
  handling EINTR and EAGAIN errors in read).
- Added support for chained client certificates
- Corrected more issues related to double frees
http://issues.outoforder.cc/view.php?id=102

** Version 0.5.5 (2009-06-13)
- Removed limits on CA certificate loading. Reported by
  Sander Marechal and Jack Bates.
- Do not allow sending empty TLS packets even when instructed to.
  This had the side effect of clients closing connection.

** Version 0.5.4 (2009-01-04)
- mod_gnutls.h: modified definition to extern to avoid compilation
  errors in darwin.
- Added patch to fix issue with mod_proxy. Investigation and patch by Alain
  Knaff.
- libgnutls detection uses pkg-config.

** Version 0.5.3 (2008-10-16)
- Corrected bug to allow having an OpenPGP-only web site.
- Increased Max handshake tries due to interrupted system calls.

** Version 0.5.2 (2008-06-29)
- Depend on gnutls 2.4 which has openpgp support in main library.

** Version 0.5.1 (2008-03-05)
- Added --disable-srp configure option
- Better check for memcache (patch by Guillaume Rousse)
- Corrected possible memory leak in DBM support for resuming sessions.

** Version 0.5.0-alpha (2008-01-24)
- Added support for OpenPGP keys. The new directives are:
  GnuTLSPGPKeyringFile, GnuTLSPGPCertificateFile, GnuTLSPGPKeyFile

** Version 0.4.2 (2007-12-10)
- Added support for sending a certificate chain.
- Corrected bug which did not allow the TLS session cache to be used.
- Do not allow resuming sessions on different servers.

** Version 0.4.1 (2007-12-03)
- Added support for subject alternative names in certificates.
Only one per certificate is supported.
- New enviroment variables: SSL_CLIENT_M_VERSION, SSL_CLIENT_S_SAN%,
SSL_CLIENT_S_TYPE, SSL_SERVER_M_VERSION, SSL_SERVER_S_SAN%, SSL_SERVER_S_TYPE
- The compatibility mode can now be enabled explicitely with the
%COMPAT keyword at the GnuTLSPriorities string. It is no longer the default.
- Check for GnuTLSPriorities directive. This corrects a segfault. Thanks
to David Hrbáč.
- Better handling of GnuTLSDHFile and GnuTLSRSAFile.
- No longer default paths for RSA and DH parameter files.