Reverse Engeeniring

[Loic Dachary]

[english version is included at the end]

---
        Bonjour,

        Un logiciel propriétaire est vendu avec le texte suivant inclus
dans la licence:

"therefore you agree not to modify the Software or attempt to reverse
engineer, decompile, or disassemble the Software, except and only to the
extent that such activity is expressly permitted by applicable law
notwithstanding this limitation."

        Si je me souviens bien, le reverse-engineering d'un protocole
de communication est légal en Europe. Le reverse-engineering du logiciel
propriétaire lui même peut ne pas être autorisé. Mais le reverse-engineering
dans le seul but de comprendre le protocole de communication que ce logiciel
utilise et l'écriture d'un Logiciel Libre totalement différent qui est
capable de comprendre ce protocol serait légal.

        Ce dont je suis certain c'est que l'étude d'un protocole de
communication afin d'écrire un logiciel compatible, sans
reverse-engineering, est légal. C'est bien entendu un petit peu plus
compliqué car il faut alors avoir recours à des méthodes permettant de
capturer les flux de communication que ce logiciel emet et reçoit sans
observer le code (binaire ou source).

        Je serais reconnaissant si vous pouviez fournir de l'information
à ce sujet. Idéalement, un pointeur vers un texte de référence serait
parfait.

        Merci par avance,

---
        Hi,

        A proprietary software is sold with the following included in the
license:

"therefore you agree not to modify the Software or attempt to reverse
engineer, decompile, or disassemble the Software, except and only to the
extent that such activity is expressly permitted by applicable law
notwithstanding this limitation."

        IIRC, reverse-engineering a communication protocol is legal in
Europe. Reverse-engineering a proprietary software itself may not be
permitted. But reverse-engineering for the sole purpose of
understanding the communication protocol this software is using and
writing a completly different Free Software that is able to understand
this protocol might be allowed.

        What I know for sure is that studying a communication protocol
in order to write a compatible software, without reverse-engineering, is
legal. Of course this is a bit more complex because you need methods to
capture the input/output data flows of the software without looking at
the code (binary or source).

        I'd be gratefull if you could provide some information on this
subject. Ideally, a pointer to a reference document would be great.

        Thanks in advance,

-- 
Loic   Dachary         http://www.dachary.org/  address@hidden
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