I opened a ticket with IBM on this question. Their response:
Informix Client SDK gives you the option of using IBM GSKit or OpenSSL when you install it. Informix Client SDK does not have the OpenSSL binaries bundled with it. It simply uses the OpenSSL that is installed on the server.
I think we started giving the IBM GSKit vs. OpenSSL option beginning with Informix Client SDK 4.50.FC6. The latest version of Informix Client SDK is 4.50.FC10.
We support a minimum OpenSSL version of 1.0.x or later.
Posting this in case this thread comes up in someone's search results.
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mark collins
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