Who should read this?
Anyone maintaining a Free Open Source Software (FOSS) project who needs either a cryptographic library or an SSL library and who wants to use or integrate Mbed TLS in the software.
Can I use Mbed TLS in my Open Source project?
In short: Yes, you can. However, there are a few rules. As a result, a lot of Open Source projects worldwide already use Mbed TLS.
We encourage and support the use of the Mbed TLS library in Open Source projects. You can use Mbed TLS even if your project does not use the Apache or GPL license itself.
How does using Mbed TLS in a non-Apache and non-GPL project work?
You should check if the license you use is more compatible with the Apache 2.0 license or the GPL license because that might differ by the license type you use.
In general, it's easier to mix with the Apache 2.0 license than with the GPL license.