From: Ken Brown <kbrown@cornell.edu>
To: cygwin-developers@cygwin.com
Subject: Re: AF_UNIX status report
Date: Sun, 22 Nov 2020 15:44:19 -0500 [thread overview]
Message-ID: <c817ecc7-79da-4af1-560b-8f1d2cf0ecb5@cornell.edu> (raw)
In-Reply-To: <20201118083447.GL41926@calimero.vinschen.de>
On 11/18/2020 3:34 AM, Corinna Vinschen wrote:
> On Nov 17 14:57, Ken Brown via Cygwin-developers wrote:
>> On 11/9/2020 4:08 AM, Corinna Vinschen wrote:
>>> The duplicated handle has to be closed at one point but otherwise
>>> the approach makes sense.
>>
>> After wasting a ridiculous amount of time because of careless mistakes with
>> handle duplication, I've finally gotten something working (currently for
>> disk files only and with some limitations that have to removed). I've
>> pushed it to the topic/af_unix branch in case you want to review it and/or
>> test it.
>
> This is soooo fantastic! Apart from files, the nexst most interesting
> case is sharing a socket, probably. We could activcate the 2nd half of
> privilege separation in sshd then.
I've pushed a first attempt to implement sending socket descriptors, but I
haven't yet tested it. I'll try to find a small test program and then, if all
goes well, take a look at sshd.
>> If you do test it, the main limitation currently is that the sending process
>> can't exit until the receiving process has received and processed the
>> SCM_RIGHTS data.
>
> While this is strictly a flaw, that may not be much of a limitation.
> It would be interesting to know how many applications send descriptors
> just to exit immediately. Not so many, probably.
I don't know, but I've reduced the effect of the limitation. Now the sending
process waits up to about 100ms for an ack from the receiving process before
closing the socket. I have no idea if 100ms is reasonable in the real world,
but it's big enough for my test programs and small enough that I don't notice
the delay when I run the programs interactively.
Ken
next prev parent reply other threads:[~2020-11-22 20:44 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-26 22:04 Ken Brown
2020-10-27 9:43 ` Corinna Vinschen
2020-10-29 20:19 ` Ken Brown
2020-10-29 21:53 ` Joe Lowe
2020-10-30 9:20 ` Corinna Vinschen
2020-11-03 15:43 ` Ken Brown
2020-11-04 12:03 ` Corinna Vinschen
2020-11-05 14:23 ` Ken Brown
2020-11-05 17:21 ` Corinna Vinschen
2020-11-05 19:01 ` Ken Brown
2020-11-05 19:54 ` Joe Lowe
2020-11-06 4:02 ` Ken Brown
2020-11-05 23:41 ` Ken Brown
2020-11-06 9:12 ` Corinna Vinschen
2020-11-07 22:25 ` Ken Brown
2020-11-08 22:40 ` Ken Brown
2020-11-09 9:08 ` Corinna Vinschen
2020-11-17 19:57 ` Ken Brown
2020-11-18 8:34 ` Corinna Vinschen
2020-11-22 20:44 ` Ken Brown [this message]
2020-11-23 8:43 ` Corinna Vinschen
2020-11-26 17:06 ` Ken Brown
2020-12-15 17:33 ` Ken Brown
2020-12-16 9:29 ` Corinna Vinschen
2020-12-16 21:09 ` Ken Brown
2020-12-17 15:54 ` Ken Brown
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