Mouse events in shared connections are locked to one viewer at a time.
If the a mouse drag is happening in the first viewer, the second viewer
can't interfere unless the first viewer has been inactive for a set
amount of time. This timeout was put in place in
71c83b4793 to handle the case where the
first viewer disconnects while the mouse drag is happening. Prior to the
timeout, this resulted in all input being blocked.
This commit increases this timeout from 3 seconds to 10 seconds. This is
to minimize the risk of this happening during "normal" use. With this
change, the first viewer has to be inactive for 10 seconds before the
second viewer can take control again.
In the case where the first viewer disconnects, a waiting time of 10
seconds for the second viewer seems very reasonable.
The common use case is probably to only listem to the systemd provided
socket when using socket activation, but it might not be the only use
case. Make sure things can be combined if explicitly requested.
VNCServerST: Add a timeout to pointer button ownership
When one clients holds down a button on the pointer device (probably
dragging something), other clients' attempts at pointer operations
are denied. This yields a sane user experience, but with limits.
When one clients starts dragging, and then his network connection fails,
other clients are denied access to the pointer until the VNC server
finally discovers that the connection is dead and closes it. This can
take about 15 minutes.
Add a timeout to this policy: If we don't hear from the client for 3
seconds, other clients are allowed to control the pointer once more.
This solves the problem that one failing network could make the server
completely deaf to other clients for a long time.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
VNCSConnectionST: Release mouse button(s) on close
When the connection is severed, release all mouse buttons.
This fixes an issue with x0vncserver where the local display
would stop responding to mouse events if the connection closes
while the remote user was holding down a mouse button.
To reproduce, start a VNC client, press and hold a mouse button
and then kill the connection (e.g. close client, kill server,
yank network cable). This caused the local screen to no longer
respond to any mouse-down events until a VNC client reconnects
and clicks anywhere.
This may inject a "mouse release" event while closing, however,
if you click on your screen and then yank the mouse cable, a mouse
release event also would not come unexpectedly, so the cure's
side effects aren't as bad as the disease.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
x0vncserver: Add support for systemd socket activation
systemd can pass in sockets as file descriptors 3 and beyond. Allows
the server to use socket activation.
When triggered by systemd, no other listening sockets (e.g. rfbport) will
be activated.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
It's a reoccurring issue that users try to build individual components
by pointing cmake at a specific subdirectory, e.g. 'cmake vncviewer'.
CMake, unfortunately, has insufficient protection against this so we'll
need to add a manual check.
This commit only adds it to the most likely places for misuse so we
don't have to pollute every CMakeLists.txt.
Replace INITARGS with void in function parameter list
Most compilers currently accept arbitrary identifiers in this place
and ignore then, but this is going to change and turn into an error.
(It prevents compilers from diagnosing misspelled type names,
and the resulting declaration is not a prototype, so no type
errors will be reported at call sites.)
Add option to run vncsession without forking and detaching
Option is -D, which is what sshd uses for the same option.
Also add description of the new option to the vncsession
man page.
Tested on Void Linux using the new option, also tested on
Fedora without using the new option.
Resolves #1649
This change makes the ZRLEEncoder respect a client's desired
compressionLevel. The ZlibLevel option is marked deprecated and removed
from the manpages.
This is mainly a copy of XKeysymToString() from libX11. We've also added
a wrapper that still gives a string, even if there is no name for the
requested keysym.
This grows the binaries a bit, but not with any extreme amount so is
hopefully worth it to get better debug logging.
We user the real, not the effective user ID, to check if the user is
allowed to log in with the "Plain" security types. Otherwise it would be
necessary to log in as root when Xvnc is installed with the set-user-id
bit on.
Signed-off-by: Carlos Santos <casantos@redhat.com>
This permits to enable PAM for the effective user of the Xvnc process by
adding this to ~/.vnc/config or /etc/tigervnc/vncserver-config-defaults:
SecurityTypes=TLSPlain
PlainUsers=%u
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2233204
Signed-off-by: Carlos Santos <casantos@redhat.com>