[openssl-users] Openssl asynchronous operation in real network
Matt Caswell
matt at openssl.org
Fri Jan 11 09:41:49 UTC 2019
On 10/01/2019 18:09, Ananthu Unnikrishnan wrote:
> Hi Matt,
>
> Thanks a lot for the reply.
>
> After calling ASYNC_pause_job() from the engine, control will transfer to
> the place where we start the ASYNC_start_job right? So how can we write the code
> to put a trigger on fd in the same thread?
I'm not saying you can't use threads to do this - only that you need to be
careful about using them and must obey the rules.
> If I am wrong please correct me.
> Also if u can suggest where resume operation should be done, it would be helpful.
Typically the calling application will wait on the fd (e.g. using "select" or
similar) until it is readable. Once it sees the fd as readable then it calls
ASYNC_start_job() again.
As an aside you may also be interested in this PR that is currently being reviewed:
https://github.com/openssl/openssl/pull/7573
This adds an alternative mechanism for signalling other than using fds (i.e. to
use a callback instead) and will be available in OpenSSL 3.0 when it gets released.
Matt
>
> On Thu, Jan 10, 2019 at 10:11 PM Matt Caswell <matt at openssl.org
> <mailto:matt at openssl.org>> wrote:
>
>
>
> On 10/01/2019 09:39, Ananthu Unnikrishnan wrote:
> > Hi all,
> >
> > We are not able to access the waitctx address from the job address
> using
> > ASYNC_get_wait_ctx(job) from a thread which starts in the bind section of the
> > dynamic engine. The job address is the same as that we got
> > using ASYNC_get_current_job. Can anyone help on this?
>
> It's very unclear from the your various emails what you are trying to achieve
> and the problem that you are experiencing.
>
> From the above it sounds like you are starting threads from inside your dynamic
> engine? ASYNC_JOBs are always local to a thread. When a job is started it is
> associated with the current thread. So ASYNC_get_current_job() returns the job
> associated with the current thread. Similarly if you pause a job,
> ASYNC_pause_job() must be called from that same thread. Finally if you restart a
> paused job it must also be restarted on the same thread.
>
> If you are starting new threads from within your engine then extreme care must
> be taken to obey the above rules - otherwise you are likely to get strange
> results.
>
> Matt
>
>
> >
> >
> >
> > On Tue, Jan 8, 2019 at 11:26 AM Ananthu Unnikrishnan
> <ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>
> > <mailto:ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>>> wrote:
> >
> > Can anyone please help on this? If u need any additional information
> please
> > let me know.
> >
> > On Mon, Jan 7, 2019 at 6:25 PM Ananthu Unnikrishnan
> <ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>
> > <mailto:ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>>> wrote:
> >
> > Hi all,
> >
> > Adding more details to the previous mail. We have edited the OpenSSL
> > code for implementing the polling for changed fd's as in OpenSSL speed
> > command. Attached the code snippet of the same along with this mail.
> > Mentioned below some observations which found doubtful:
> >
> > 1) We have got prints in ASYNC_FINISH case, before getting print in
> > ASYNC_PAUSE case. Attaching the log also, so you can understand
> easily.
> > 2) Shown below the code snippet which we have written to provide a
> write
> > on fd.
> >
> > if ((waitctx = ASYNC_get_wait_ctx((ASYNC_JOB *)job)) == NULL) {
> > printf("In dynamic engine | waitctx == NULL : %d\n",
> __LINE__);
> > return ret;
> > }
> >
> > printf("\n----- In dynamic engine | After pausing | job is %lx |
> > waitctx in resume job %lx |-----\n", job, waitctx);
> >
> > if ((ret = ASYNC_WAIT_CTX_get_fd(waitctx, engine_id, &efd,
> > &custom)) > 0) {
> > if (write(efd, &buf, sizeof(uint64_t)) == -1) {
> > printf("\nFailed to write\n");
> > }
> > }
> >
> > Here waitctx is getting NULL when we tried to fetch waitctx using
> > ASYNC_get_wait_ctx(). We have printed data of sizeof(ASYNC_JOB)
> ie.1176
> > bytes contained in the job address from the engine, we got
> correct data
> > before calling ASYNC_pause() and but got half data zero data when we
> > tried to access the same address after ASYNC_pause().
> >
> > Attaching both job structure contents before and after calling
> > ASYNC_pause(). Also, we got the correct data in the same address
> when we
> > have printed from ssl_start_async_job() before polling starts,
> where we
> > have started the async_job
> > .
> > The prints starting with "In dynamic engine" are prints inside the
> > engine, rest prints are from ss/ssl_lib.c. Kindly check this and
> please
> > point out if anything is wrong somewhere. Thanks in advance.
> >
> >
> > On Sun, Jan 6, 2019 at 10:30 AM Ananthu Unnikrishnan
> > <ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>
> <mailto:ananthuu741 at gmail.com <mailto:ananthuu741 at gmail.com>>> wrote:
> >
> > Hi all,
> >
> > We have implemented a dynamic engine and tested in the
> async
> > mode using OpenSSL speed command. But in a real network
> scenario, we
> > have seen only starting the async_job(in file ssl/ssl_lib.c,
> > function: ssl_start_async_job) in the OpenSSL. We haven't seen
> > polling async_fd's for resuming the job as in apps/speed.c(in
> speed
> > command case).
> > So can anyone please suggest any solution for resuming the
> > async_jobs in real network scenario? Thanks in advance.
> >
> >
> >
> >
> >
> > --
> > With best Regards,
> >
> > Ananthu
> >
> >
> >
> >
> > --
> > With best Regards,
> >
> > Ananthu
> >
> >
> >
> >
> > --
> > With best Regards,
> >
> > Ananthu
> >
> >
> >
> --
> openssl-users mailing list
> To unsubscribe: https://mta.openssl.org/mailman/listinfo/openssl-users
>
>
>
> --
> With best Regards,
>
> Ananthu
>
>
>
More information about the openssl-users
mailing list