HAPROXY's license - 2006/06/15

Historically, haproxy has been covered by GPL version 2. However, an issue

appeared in GPL which will prevent external non-GPL code from being built

using the headers provided with haproxy. My long-term goal is to build a core

system able to load external modules to support specific application protocols.

Since some protocols are found in rare environments (finance, industry, ...),

some of them might be accessible only after signing an NDA. Enforcing GPL on

such modules would only prevent them from ever being implemented, while not

providing anything useful to ordinary users.

For this reason, I *want* to be able to support binary only external modules

when needed, with a GPL core and GPL modules for standard protocols, so that

people fixing bugs don't keep them secretly to try to stay over competition.

The solution was then to apply the LGPL license to the exportable include

files, while keeping the GPL for all the rest. This way, it still is mandatory

to redistribute modified code under customer request, but at the same time, it

is expressly permitted to write, compile, link and load non-GPL code using the

LGPL header files and not to distribute them if it causes a legal problem.

Of course, users are strongly encouraged to continue the work under GPL as long

as possible, since this license has allowed useful enhancements, contributions

and fixes from talented people around the world.

Due to the incompatibility between the GPL and the OpenSSL licence, you must

apply the GPL/LGPL licence with the following exception:

This program is released under the GPL with the additional exemption that

compiling, linking, and/or using OpenSSL is allowed.

The text of the licenses lies in the "doc" directory. All the files provided in

this package are covered by the GPL unless expressly stated otherwise in them.

Every patch or contribution provided by external people will by default comply

with the license of the files it affects, or be rejected.

Willy Tarreau - w@1wt.eu