cannot pass TLSSocket to child process

[endel]

• Node.js Version: 8.6.0
• OS: OSX

How can I pass a TLSSocket to a child process? (created from "https" module)

I'm having this issue:

internal/child_process.js:630
        throw new errors.TypeError('ERR_INVALID_HANDLE_TYPE');
        ^

TypeError [ERR_INVALID_HANDLE_TYPE]: This handle type cannot be sent

Pseudo-code:

httpsServer.on('request', (request, response) => {
  let socket = request.connection;
  myChildProcess.send({}, socket);
})

This works fine using "http" module. The error happens only when using "https".

Thanks in advance.

[bnoordhuis]

You can't, TLSSockets have process-specific state.

What you can do is transfer the net.Socket instance before the TLS handshake is initiated: start a normal net.Server in process A, send socket to process B, call new TLSSocket(socket) in B.

[endel]

Thanks @bnoordhuis, do you know which event can I get the net.Socket from? Perhaps it's possible to get a net.Socket instance from the TLSSocket?

[bnoordhuis]

You mean in process B? process.on('message', (msg, handle) => { /* ... */ }). The cluster and child_process reference documentation has more info.

Perhaps it's possible to get a net.Socket instance from the TLSSocket?

That wouldn't do any good. Once the TLS handshake starts, it's too late.

[endel]

@bnoordhuis actually, you mentioned that's possible to get the net.Socket before the TLS handshake. I'm wondering which event exactly is before TLS handshake where I can get the net.Socket from? Thanks!

[bnoordhuis]

The key point is that you start a plain TCP server (no TLS) in process A. An incoming connection is handed off to process B which wraps it in a TLSSocket and initiates the handshake.

[lahsenifl]

What you can do is transfer the net.Socket instance before the TLS handshake is initiated: start a normal net.Server in process A, send socket to process B, call new TLSSocket(socket) in B.
@bnoordhuis can you provide example for this?

[ackava]

In theory it is possible, as TLS Socket has ability to do session resumption.

1. In Process A Set pauseOnConnect to true, once TLS Socket is initialized
2. Unwrap socket and collect session buffer (which contains SSL Certificate and some other information)
3. Send session buffer to Process B
4. Send plain socket to Process B
5. In Process B Initialize new TLS Socket from plain socket and pass session in a constructor of TLS Socket to resume the SSL session

However, unless node makes this process easier, it is little difficult to get it working.