DRAFT: Implement TLS/SSL Support for EPMD

[karomnii]

Description
This PR introduces optional TLS/SSL encryption for EPMD (Erlang Port Mapper Daemon) communications. It updates both the C-based EPMD daemon and the erl_epmd Erlang client to securely handle encrypted socket connections.

Key Changes

• EPMD Daemon (C-side): Linked OpenSSL libraries and added -tls <cert_path> <key_path> command-line arguments. Replaced direct socket read/write operations with wrappers that dynamically use standard TCP or TLS depending on the configuration.
• Erlang Client (erl_epmd.erl): Added logic to check for epmd_ssl_options in the application environment. If present, the client routes connections through the ssl module instead of gen_tcp and natively handles the corresponding SSL socket messages and connection states.

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Results for commit b46095d

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// Erlang/OTP Github Action Bot

[joaohf]

Hi,

Is that possible to make it build time configurable ?

[karomnii]

Hi @joaohf,
Could you clarify the question a little bit more? I am not sure that I understand what you mean by build-time configurable. Right now, it is configurable by the user at start time.

[IngelaAndin]

@karomnii Thank you very much for wanting to contribute this. We are very much interested in doing work in this area. Alas we do not really have time to handle this right away, it is a bigger job and we will need a full team effort after vacation period. Independent on how this will be solved in the end , we think your effort will be a valuable input. And I think this will amount to improvements being made regardless if you will have time to continue or not. But lets leave that decision for later.