fixed a bug where client could not load tls-engine

[Hyeongon-Kim]

when loading tls-engine from the client, if client_opts_set is called before client_connect, an error 'setting TLS engine' occurs. so i modified to call the net__init_tls function in the mosquitto_lib_init function.

Signed-off-by: Hyeongon Kim [email protected]

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when loading tls-engine from the client, if client_opts_set is called before client_connect, an error 'setting TLS engine' occurs. so i modified to call the net__init_tls function in the mosquitto_lib_init function.

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before :

after :

[ralight]

Thank you for looking at this, the TLS engine code isn't currently covered by tests and isn't something I've spent a huge amount of time on.

The reason that the TLS initialisation happens where it does is to avoid always that initialisation if TLS is not in use. I do not want to move net__init_tls() back to the general lib init function. Could we instead add a call to net__init_tls() in mosquitto_string_option() for the MOSQ_OPT_TLS_ENGINE? I think that should satisfy both of us.

Do you have any experience of how to port engine related code to openssl 3? I haven't spent any time looking into that side of things and would definitely appreciate some insight.