[openssl-dev] Questions about ASYNC API for engines and moving read buffer.

[Emeric Brun]

Hi,

I'm working on an ASYNC engine designed to offload crypto on multiple thread for monoproc applications.

No issue on asymetric crypto part but i'm facing a problem concerning ciphers:

When an SSL_read operation perform a do_cipher decrypt:

My engine defer the do_cipher to be processed by an other thread using the output buffer provided by to the do_cipher method.

After that it performs an ASYNC_pause_job(). On the application side it results on a WANT_ASYNC error.

The application consider that nothing was written on its output, and the buffer read buffer is reused for something else.

SSL_read is called a second time after receiving the event on the async fd. But this time the app used a different buffer.

On the engine side, i don't see any change on the do_cipher output buffer which would allow to manage the issue with a memcopy.

So my question is:

Is there a way to perform ciphering with an ASYNC engine when the app don't reuse the same buffer.

R,
Emeric Brun