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RE: Issues implementing an async certificate validation engine

From: Valerio Di Gregorio \(vadigreg\) via curl-library <>
Date: Wed, 12 Feb 2020 22:47:38 +0000

I'm in a single-threaded environment and validation can only be done by another process. Actual validation involves IPC, so it can only be async and must not be blocking.


-----Original Message-----
From: Daniel Stenberg <>
Sent: Wednesday, February 12, 2020 11:45 PM
To: Valerio Di Gregorio (vadigreg) <>
Cc: Valerio Di Gregorio (vadigreg) via curl-library <>
Subject: RE: Issues implementing an async certificate validation engine

On Wed, 12 Feb 2020, Valerio Di Gregorio (vadigreg) wrote:

> Thanks for your reply. I'm doing the cert verfication in the callback
> and the operation is async. The way the async verification is achieved
> is by using ASYNC_pause_job (which internally does a longjmp).
> Callback won't return, because the async job gets paused. Once async
> validation is done, SSL async job can resume. It's the resumed
> callback that will finally return with a validation result.

If the callback won't return until the verification is done (and you have a validation result), why do it async in the first place? What's the benefit?

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Received on 2020-02-12