Implementation experience has shown that the original plan for async wait
fds was too simplistic. Originally the async logic created a pipe internally
and user/engine code could then get access to it via API calls. It is more
flexible if the engine is able to create its own fd and provide it to the
async code.
Another issue is that there can be a lot of churn in the fd value within
the context of (say) a single SSL connection leading to continually adding
and removing fds from (say) epoll. It is better if we can provide some
stability of the fd value across a whole SSL connection. This is
problematic because an engine has no concept of an SSL connection.
This commit refactors things to introduce an ASYNC_WAIT_CTX which acts as a
proxy for an SSL connection down at the engine layer.
Reviewed-by: Richard Levitte <levitte@openssl.org>
If init failed we'd like to set an error code to indicate that. But if
init failed then when the error system tries to load its strings its going
to fail again. We could get into an infinite loop. Therefore we just set
a single error the first time around. After that no error is set.
Reviewed-by: Rich Salz <rsalz@openssl.org>
The new init functions can fail if the library has already been stopped. We
should be able to indicate failure with a 0 return value.
Reviewed-by: Rich Salz <rsalz@openssl.org>
This was done by the following
find . -name '*.[ch]' | /tmp/pl
where /tmp/pl is the following three-line script:
print unless $. == 1 && m@/\* .*\.[ch] \*/@;
close ARGV if eof; # Close file to reset $.
And then some hand-editing of other files.
Reviewed-by: Viktor Dukhovni <viktor@openssl.org>
In the async code for MacOS/X define _XOPEN_SOURCE (if not already
defined) as early as possible. We must do this before including
any header files, because on MacOS/X <stlib.h> includes <signal.h>
which includes <ucontext.h>. If we delay defining _XOPEN_SOURCE
and include <ucontext.h> after various system headers are included,
we are very likely to end up with the wrong (truncated) definition
of ucontext_t.
Also, better error handling and some code cleanup in POSIX fibre
construction and destruction. We make sure that async_fibre_makecontext()
always initializes the fibre to a state that can be freed.
For all implementations, check for error returns from
async_fibre_makecontext().
Reviewed-by: Matt Caswell <matt@openssl.org>
Implements Thread Local Storage in the windows async port. This also has
some knock on effects to the posix and null implementations.
Reviewed-by: Rich Salz <rsalz@openssl.org>
In theory the pthreads approach for Thread Local Storage should be more
portable.
This also changes some APIs in order to accommodate this change. In
particular ASYNC_init_pool is renamed ASYNC_init_thread and
ASYNC_free_pool is renamed ASYNC_cleanup_thread. Also introduced ASYNC_init
and ASYNC_cleanup.
Reviewed-by: Rich Salz <rsalz@openssl.org>
A lot of the pool handling code was in the arch specific files, but was
actually boiler plate and the same across the implementations. This commit
moves as much code as possible out of the arch specific files.
Reviewed-by: Rich Salz <rsalz@openssl.org>
We were using _pipe to create a pipe on windows. This uses the "int" type
for its file descriptor for compatibility. However most windows functions
expect to use a "HANDLE". Probably we could get away with just casting but
it seems more robust to use the proper type and main stream windows
functions.
Reviewed-by: Rich Salz <rsalz@openssl.org>
There are potential deadlock situations that can occur if code executing
within the context of a job aquires a lock, and then pauses the job. This
adds an ability to temporarily block pauses from occuring whilst performing
work and holding a lock.
Reviewed-by: Rich Salz <rsalz@openssl.org>
If config'd without -d (--debug), asynctest was crashing with:
*** longjmp causes uninitialized stack frame ***
This is because gcc will add certain checks for some functions
(including longjmp). The checks assume you can only longjmp down the
stack not up. However, if we are actually jumping to a different
fibre then it can appear as if we are going up the stack when we are
not really. This change disables the check.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Add some clarifications to the async documentation. Also changed
ASYNC_pause_job() so that it returns success if you are not within the
context of a job. This is so that engines can be used either asynchronously
or synchronously and can treat an error from ASYNC_pause_job() as a real
error.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Don't recreate a new ASYNC_CTX every time we call ASYNC_start_job() - the
same one can be used for the life of the thread. Instead we only free it
up when we call ASYNC_free_pool().
Reviewed-by: Rich Salz <rsalz@openssl.org>
Initial API implemented for notifying applications that an ASYNC_JOB
has completed. Currently only s_server is using this. The Dummy Async
engine "cheats" in that it notifies that it has completed *before* it
pauses the job. A normal async engine would not do that.
Only the posix version of this has been implemented so far, so it will
probably fail to compile on Windows at the moment.
Reviewed-by: Rich Salz <rsalz@openssl.org>
It is expensive to create the ASYNC_JOB objects due to the "makecontext"
call. This change adds support for pools of ASYNC_JOB objects so that we
don't have to create a new ASYNC_JOB every time we want to use one.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Removed the function ASYNC_job_is_waiting() as it was redundant. The only
time user code has a handle on a job is when one is waiting, so all they
need to do is check whether the job is NULL. Also did some cleanups to
make sure the job really is NULL after it has been freed!
Reviewed-by: Rich Salz <rsalz@openssl.org>
Create a "null" async implementation for platforms that lack support. This
just does nothing when called and therefore performs synchronously.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Provides support for running asynchronous jobs. Currently this is completely
stand alone. Future commits will integrate this into libssl and s_server/
s_client. An asynchronous capable engine will be required to see any benefit
from this capability.
Reviewed-by: Rich Salz <rsalz@openssl.org>
