e9b78e3fb1
On loss detection timer expiration, qc_dgrams_retransmit() is used to reemit lost packets. Different code paths are present depending on the active encryption level. If Initial level is still initialized, retransmit is performed both for Initial and Handshake spaces, by first retrieving the list of lost frames for each of them. Prior to this patch, Handshake level was always registered for emission after Initial, even if it dit not have any frame to reemit. In this case, most of the time it would result in a datagram containing Initial reemitted frames packet coalesced with a Handshake packet consisting only of a PADDING frame. This is because padding is only added for the last registered QEL. For QUIC backend support, this may cause issues. This is because contrary to QUIC server side, Initial and Handshake levels keys are not derived simultaneously for a QUIC client. Thus, if the latter keys are unavailable, Handshake packet cannot be encoded in sending, leaving a single Initial packet. However, this is now too late to add PADDING. Thus the resulting datagram is invalid : this triggers the BUG_ON() assert failure located on qc_txb_store(). This patch fixes this by amending qc_dgrams_retransmit(). Now, Handshake level is only registered for emission if there is frame to retransmit, which implies that Handshake keys are already available. Thus, PADDING will now either be added at Initial or Handshake level as expected. Note that this issue should not be present on QUIC frontend, due to Initial and Handshake keys derivation almost simultaneously. However, this should still be backported up to 3.0.
HAProxy
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:
- doc/intro.txt for a quick introduction on HAProxy
- doc/configuration.txt for the configuration's reference manual
- doc/lua.txt for the Lua's reference manual
- doc/SPOE.txt for how to use the SPOE engine
- doc/network-namespaces.txt for how to use network namespaces under Linux
- doc/management.txt for the management guide
- doc/regression-testing.txt for how to use the regression testing suite
- doc/peers.txt for the peers protocol reference
- doc/coding-style.txt for how to adopt HAProxy's coding style
- doc/internals for developer-specific documentation (not all up to date)
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.