HAProxy - Load balancer
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Willy Tarreau 336170007c BUG/MEDIUM: ssl: take care of second client hello
For a long time we've been observing some sporadic leaks of ssl-capture
pool entries on haproxy.org without figuring exactly the root cause. All
that was seen was that less calls to the free callback were made than
calls to the hello parsing callback, and these were never reproduced
locally.

It recently turned out to be triggered by the presence of "curves" or
"ecdhe" on the "bind" line. Captures have shown the presence of a second
client hello, called "Change Cipher Client Hello" in wireshark traces,
that calls the client hello callback again. That one wasn't prepared for
being called twice per connection, so it allocates an ssl-capture entry
and assigns it to the ex_data entry, possibly overwriting the previous
one.

In this case, the fix is super simple, just reuse the current ex_data
if it exists, otherwise allocate a new one. This completely solves the
problem.

Other callbacks have been audited for the same issue and are not
affected: ssl_ini_keylog() already performs this check and ignores
subsequent calls, and other ones do not allocate data.

This must be backported to all supported versions.
2025-10-09 17:06:49 +02:00
.github CI: github: build halog on the vtest job 2025-09-26 16:29:29 +02:00
addons MINOR: applet: Add a flag to know an applet is using HTX buffers 2025-08-25 11:11:05 +02:00
admin ADMIN: reload: introduce -vv mode 2025-09-29 19:29:10 +02:00
dev DEV: patchbot: use git reset+checkout instead of pull 2025-10-08 04:38:35 +02:00
doc MAJOR: proxy: enable abortonclose by default on TLS listeners 2025-10-08 10:36:59 +02:00
examples MINOR: mailers: warn if mailers are configured but not actually used 2025-06-27 16:41:18 +02:00
include MEDIUM: htx: Remove the HTX extra field 2025-10-08 11:10:42 +02:00
reg-tests MAJOR: proxy: enable abortonclose by default on HTTP proxies 2025-10-08 10:29:41 +02:00
scripts CI: scripts: build curl with ECH support 2025-09-25 17:05:46 +02:00
src BUG/MEDIUM: ssl: take care of second client hello 2025-10-09 17:06:49 +02:00
tests TESTS: quic: add unit-tests for QUIC TX part 2025-09-08 14:49:03 +02:00
.cirrus.yml CI: cirrus-ci: bump FreeBSD image to 14-3 2025-10-09 14:06:48 +02:00
.gitattributes MINOR: Configure the cpp userdiff driver for *.[ch] in .gitattributes 2021-02-22 18:17:57 +01:00
.gitignore MINOR: tevt/dev: Add term_events tool 2025-01-31 10:41:50 +01:00
.mailmap DOC: update Tim's address in .mailmap 2021-09-16 09:14:14 +02:00
.travis.yml MEDIUM: mworker: remove USE_SYSTEMD requirement for -Ws 2024-11-20 12:07:38 +01:00
BRANCHES DOC: fix some spelling issues over multiple files 2021-01-08 14:53:47 +01:00
BSDmakefile BUILD: makefile: commit the tiny FreeBSD makefile stub 2023-05-24 17:17:36 +02:00
CHANGELOG [RELEASE] Released version 3.3-dev9 2025-10-03 12:12:51 +02:00
CONTRIBUTING CLEANUP: assorted typo fixes in the code and comments 2025-04-02 11:12:20 +02:00
INSTALL BUILD: makefile: bump the default minimum linux version to 4.17 2025-09-05 09:44:56 +02:00
LICENSE LICENSE: add licence exception for OpenSSL 2012-09-07 13:52:26 +02:00
MAINTAINERS MAJOR: spoe: Let the SPOE back into the game 2024-05-22 09:04:38 +02:00
Makefile IMPORT: cebtree: import version 0.5.0 to support duplicates 2025-09-16 09:23:46 +02:00
README.md DOC: change the link to the FreeBSD CI in README.md 2024-06-03 15:21:29 +02:00
SUBVERS BUILD: use format tags in VERDATE and SUBVERS files 2013-12-10 11:22:49 +01:00
VERDATE [RELEASE] Released version 3.3-dev9 2025-10-03 12:12:51 +02:00
VERSION [RELEASE] Released version 3.3-dev9 2025-10-03 12:12:51 +02:00

HAProxy

alpine/musl AWS-LC openssl no-deprecated Illumos NetBSD FreeBSD VTest

HAProxy logo

HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications.

Installation

The INSTALL file describes how to build HAProxy. A list of packages is also available on the wiki.

Getting help

The discourse and the mailing-list are available for questions or configuration assistance. You can also use the slack or IRC channel. Please don't use the issue tracker for these.

The issue tracker is only for bug reports or feature requests.

Documentation

The HAProxy documentation has been split into a number of different files for ease of use. It is available in text format as well as HTML. The wiki is also meant to replace the old architecture guide.

Please refer to the following files depending on what you're looking for:

  • INSTALL for instructions on how to build and install HAProxy
  • BRANCHES to understand the project's life cycle and what version to use
  • LICENSE for the project's license
  • CONTRIBUTING for the process to follow to submit contributions

The more detailed documentation is located into the doc/ directory:

License

HAProxy is licensed under GPL 2 or any later version, the headers under LGPL 2.1. See the LICENSE file for a more detailed explanation.