Hello,

https://www.kamailio.org/docs/modules/devel/modules/tls says:

For OpenSSL (libssl) v1.1.x, it is required to preload 'openssl_mutex_shared' library shipped by Kamailio. For more details see 'src/modules/tls/utils/openssl_mutex_shared/README.md'.

'src/modules/tls/utils/openssl_mutex_shared/README.md says:

**IMPORTANT: the workaround of using this preloaded shared library is no longer needed starting with Kamailio v5.3.0-pre1 (git master branch after September 14, 2019). The code of this shared library has been included in the core of Kamailio and the same behaviour is now achieved by default.**

This is a shared library required as a short term workaround for using Kamailio with OpenSSL (libssl) v1.1. It has to be pre-loaded before starting Kamailio.

In v1.1, libssl does not allow setting custom locking functions, using internally pthread mutexes and rwlocks, but they are not initialized with process shared option (PTHREAD_PROCESS_SHARED), which can result in blocking Kamailio worker processes.

Is preloading openssl_mutex_shared necessary for Kamailio 5.6 or is it not necessary?

If it is not necessary, why isn’t it removed from the source code?

Greetings Дилян