Use of OpenSSL is GPL-incompatible

[EionRobb]

This plugin uses OpenSSL of which there is no GPL-exception for in the libpurple GPL license. Consider switching to using the SSL functions built into libpurple or use an alternatively library such as PolarSSL

[majn]

Getting rid of OpenSSL shouldn't be easy since its used heavily. If there isn't some kind of drop-in replacement with the same functions I probably would have to refactor the whole crypto code for that.

[EionRobb]

Any movement on this? I see that there are people distributing compiled versions of this plugin which is in violation of the GPL and removing the OpenSSL portions of this plugin will help them legally distribute the plugin.

[majn]

Hi, unfortunately no. I've checked PolarSSL and GnuTLS and they both don't seem to support the IGE mode of operation that Telegram needs.
In the development version, I'm only linking against current version of libtgl, which in turn requires OpenSSL, but I fear that the advertising clause of the 4-claus BSD will still apply to my project and still make it GPL-incompatible.

To solve this someone would need to do the following changes to libtgl:

• Implement Infinite Garble Extension using the AES implementation of GnuTLS or PolarSSL
• Replace all occurrences of OpenSSL functions that are used to implement the MTProto protocol

[Croydon]

As mentioned here: #52 (comment)
the OpenSSL license is going to change to Apache v2

[majn]

Now that libtgl is ported thanks to ben and the whole thing is tested and merged into the master, I think we can finally get rid of this annoying issue :)