vnc aborts display update jobs on video mode switches and page flips.
That can cause vnc update stalls in case an unfinished vnc job gets
aborted. The vnc client will never receive the requested update then.
Fix that by copying the state from job_update back to update in that
case.
Reports complain about stalls with two or more clients being connected
at the same time, on some but not all connections. I suspect it can
also happen with a single connection, multiple connections only make
this more much likely to happen.
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1662260
Reported-by: Ying Fang <fangying1@huawei.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ying Fang <fangying1@huawei.com>
Message-id: 20190305130930.24516-1-kraxel@redhat.com
The 'qemu_acl' type was a previous non-QOM based attempt to provide an
authorization facility in QEMU. Because it is non-QOM based it cannot be
created via the command line and requires special monitor commands to
manipulate it.
The new QAuthZ subclasses provide a superset of the functionality in
qemu_acl, so the latter can now be deleted. The HMP 'acl_*' monitor
commands are converted to use the new QAuthZSimple data type instead
in order to provide temporary backwards compatibility.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Having to include qapi-events.h just for QAPIEvent is suboptimal, but
quite tolerable now. It'll become problematic when we have events
conditional on the target, because then qapi-events.h won't be usable
from target-independent code anymore. Avoid that by generating it
into separate files.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-6-armbru@redhat.com>
It is possible that the modifier state on keyup is different from the
modifier state on keydown. In that case the keycode lookup can end up
with different keys in case multiple keysym -> keycode mappings exist,
because it picks the mapping depending on modifier state.
To fix that change the lookup logic for keyup events. Instead of
looking at the modifier state check the key state and prefer a keycodes
where the key is in "down" state right now.
Fixes: abb4f2c965 keymap: consider modifier state when picking a mapping
Buglink: https://bugs.launchpad.net/bugs/1738283
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1658676
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-9-kraxel@redhat.com
Pass the keyboard state tracker handle down to keysym2scancode(),
so the code can fully inspect the keyboard state as needed. No
functional change.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-8-kraxel@redhat.com
Use the new keyboard state tracked for vnc. Allows to drop the
vnc-specific modifier state tracking code.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190122092814.14919-7-kraxel@redhat.com
When size and format of the display surface stays the same we can just
tag the guest display as dirty and be done with it.
There is no need need to resize the vnc server display or to touch the
vnc client dirty bits. On the next refresh cycle
vnc_refresh_server_surface() will check for actual display content
changes and update the client dirty bits as needed.
The desktop resize and framebuffer format notifications to the vnc
client will be skipped too.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190116101049.8929-1-kraxel@redhat.com
Most files that have TABs only contain a handful of them. Change
them to spaces so that we don't confuse people.
disas, standard-headers, linux-headers and libdecnumber are imported
from other projects and probably should be exempted from the check.
Outside those, after this patch the following files still contain both
8-space and TAB sequences at the beginning of the line. Many of them
have a majority of TABs, or were initially committed with all tabs.
bsd-user/i386/target_syscall.h
bsd-user/x86_64/target_syscall.h
crypto/aes.c
hw/audio/fmopl.c
hw/audio/fmopl.h
hw/block/tc58128.c
hw/display/cirrus_vga.c
hw/display/xenfb.c
hw/dma/etraxfs_dma.c
hw/intc/sh_intc.c
hw/misc/mst_fpga.c
hw/net/pcnet.c
hw/sh4/sh7750.c
hw/timer/m48t59.c
hw/timer/sh_timer.c
include/crypto/aes.h
include/disas/bfd.h
include/hw/sh4/sh.h
libdecnumber/decNumber.c
linux-headers/asm-generic/unistd.h
linux-headers/linux/kvm.h
linux-user/alpha/target_syscall.h
linux-user/arm/nwfpe/double_cpdo.c
linux-user/arm/nwfpe/fpa11_cpdt.c
linux-user/arm/nwfpe/fpa11_cprt.c
linux-user/arm/nwfpe/fpa11.h
linux-user/flat.h
linux-user/flatload.c
linux-user/i386/target_syscall.h
linux-user/ppc/target_syscall.h
linux-user/sparc/target_syscall.h
linux-user/syscall.c
linux-user/syscall_defs.h
linux-user/x86_64/target_syscall.h
slirp/cksum.c
slirp/if.c
slirp/ip.h
slirp/ip_icmp.c
slirp/ip_icmp.h
slirp/ip_input.c
slirp/ip_output.c
slirp/mbuf.c
slirp/misc.c
slirp/sbuf.c
slirp/socket.c
slirp/socket.h
slirp/tcp_input.c
slirp/tcpip.h
slirp/tcp_output.c
slirp/tcp_subr.c
slirp/tcp_timer.c
slirp/tftp.c
slirp/udp.c
slirp/udp.h
target/cris/cpu.h
target/cris/mmu.c
target/cris/op_helper.c
target/sh4/helper.c
target/sh4/op_helper.c
target/sh4/translate.c
tcg/sparc/tcg-target.inc.c
tests/tcg/cris/check_addo.c
tests/tcg/cris/check_moveq.c
tests/tcg/cris/check_swap.c
tests/tcg/multiarch/test-mmap.c
ui/vnc-enc-hextile-template.h
ui/vnc-enc-zywrle.h
util/envlist.c
util/readline.c
The following have only TABs:
bsd-user/i386/target_signal.h
bsd-user/sparc64/target_signal.h
bsd-user/sparc64/target_syscall.h
bsd-user/sparc/target_signal.h
bsd-user/sparc/target_syscall.h
bsd-user/x86_64/target_signal.h
crypto/desrfb.c
hw/audio/intel-hda-defs.h
hw/core/uboot_image.h
hw/sh4/sh7750_regnames.c
hw/sh4/sh7750_regs.h
include/hw/cris/etraxfs_dma.h
linux-user/alpha/termbits.h
linux-user/arm/nwfpe/fpopcode.h
linux-user/arm/nwfpe/fpsr.h
linux-user/arm/syscall_nr.h
linux-user/arm/target_signal.h
linux-user/cris/target_signal.h
linux-user/i386/target_signal.h
linux-user/linux_loop.h
linux-user/m68k/target_signal.h
linux-user/microblaze/target_signal.h
linux-user/mips64/target_signal.h
linux-user/mips/target_signal.h
linux-user/mips/target_syscall.h
linux-user/mips/termbits.h
linux-user/ppc/target_signal.h
linux-user/sh4/target_signal.h
linux-user/sh4/termbits.h
linux-user/sparc64/target_syscall.h
linux-user/sparc/target_signal.h
linux-user/x86_64/target_signal.h
linux-user/x86_64/termbits.h
pc-bios/optionrom/optionrom.h
slirp/mbuf.h
slirp/misc.h
slirp/sbuf.h
slirp/tcp.h
slirp/tcp_timer.h
slirp/tcp_var.h
target/i386/svm.h
target/sparc/asi.h
target/xtensa/core-dc232b/xtensa-modules.inc.c
target/xtensa/core-dc233c/xtensa-modules.inc.c
target/xtensa/core-de212/core-isa.h
target/xtensa/core-de212/xtensa-modules.inc.c
target/xtensa/core-fsf/xtensa-modules.inc.c
target/xtensa/core-sample_controller/core-isa.h
target/xtensa/core-sample_controller/xtensa-modules.inc.c
target/xtensa/core-test_kc705_be/core-isa.h
target/xtensa/core-test_kc705_be/xtensa-modules.inc.c
tests/tcg/cris/check_abs.c
tests/tcg/cris/check_addc.c
tests/tcg/cris/check_addcm.c
tests/tcg/cris/check_addoq.c
tests/tcg/cris/check_bound.c
tests/tcg/cris/check_ftag.c
tests/tcg/cris/check_int64.c
tests/tcg/cris/check_lz.c
tests/tcg/cris/check_openpf5.c
tests/tcg/cris/check_sigalrm.c
tests/tcg/cris/crisutils.h
tests/tcg/cris/sys.c
tests/tcg/i386/test-i386-ssse3.c
ui/vgafont.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20181213223737.11793-3-pbonzini@redhat.com>
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Eric Blake <eblake@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Stefan Markovic <smarkovic@wavecomp.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Calling error_report() in a function that takes an Error ** argument
is suspicious. vnc_init_func() does that, and then fails without
setting an error. Its caller main(), via qemu_opts_foreach(), is fine
with it, but clean it up anyway.
While there, drop a "Failed to start VNC server: " error message
prefix that doesn't really add value.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20181017082702.5581-28-armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
VNC server is calling sasl_server_init() during startup of QEMU, even
if SASL auth has not been enabled.
This may create undesirable warnings like "Could not find keytab file:
/etc/qemu/krb5.tab" when the user didn't configure SASL on host and
started VNC server.
Instead, only initialize SASL when needed. Note that HMP/QMP "change
vnc" calls vnc_display_open() again, which will initialize SASL if
needed.
Fix assignment in if condition, while touching this code.
Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1609327
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180907063634.359-1-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The generated qapi_event_send_FOO() take an Error ** argument. They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().
Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.
Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The 'tls-creds' option accepts the name of a TLS credentials
object. This replaced the usage of 'tls', 'x509' and 'x509verify'
options in 2.5.0. These deprecated options were grandfathered in
when the deprecation policy was introduded in 2.10.0, so can now
finally be removed.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180725092751.21767-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Set magic cookie on initialization. Clear on cleanup. Sprinkle a bunch
of assert()s checking the cookie, to verify the pointer is valid.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180507102254.12107-1-kraxel@redhat.com
When vnc_client_read() return value is -1
vs is not valid any more.
Fixes: d49b87f0d1
Reported-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180420084820.3873-1-kraxel@redhat.com
Secondary displays in multihead setups are allowed to have a NULL
DisplaySurface. Typically user interfaces handle this by hiding the
window which shows the display in question.
This isn't an option for vnc though because it simply hasn't a concept
of windows or outputs. So handle the situation by showing a placeholder
DisplaySurface instead. Also check in console_select whenever a surface
is preset in the first place before requesting an update.
This fixes a segfault which can be triggered by switching to an unused
display (via vtrl-alt-<nr>) in a multihead setup, for example using
-device virtio-vga,max_outputs=2.
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 20180308161803.6152-1-kraxel@redhat.com
Move qapi-schema.json to qapi/, so it's next to its modules, and all
files get generated to qapi/, not just the ones generated for modules.
Consistently name the generated files qapi-MODULE.EXT:
qmp-commands.[ch] become qapi-commands.[ch], qapi-event.[ch] become
qapi-events.[ch], and qmp-introspect.[ch] become qapi-introspect.[ch].
This gets rid of the temporary hacks in scripts/qapi/commands.py,
scripts/qapi/events.py, and scripts/qapi/common.py.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-28-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: Fix trailing dot in tpm.c, undo temporary hack for OSX toolchain]
Signed-off-by: Eric Blake <eblake@redhat.com>
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.
The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h. Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.
To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects. The next commit will
improve it further.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
Pass the modifier state to the keymap lookup function. In case multiple
keysym -> keycode mappings exist look at the modifier state and prefer
the mapping where the modifier state matches.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180222070513.8740-6-kraxel@redhat.com
The 'vs->as.freq' value is a signed integer, which is read from an
unsigned 32-bit int field on the wire. There is thus a risk of overflow
on 32-bit platforms. Move the frequency limit checking to be done at
time of read before casting to a signed integer.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205114938.15784-4-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For very large framebuffers, it is theoretically possible for the result
of 'vs->throttle_output_offset * VNC_THROTTLE_OUTPUT_LIMIT_SCALE' to
exceed the size of a 32-bit int. For this to happen in practice, the
video RAM would have to be set to a large enough value, which is not
likely today. None the less we can be paranoid against future growth by
using division instead of multiplication when checking the limits.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205114938.15784-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
On one of our client's node, due to trying to read from closed ioc,
a segmentation fault occured. Corresponding backtrace:
0 object_get_class (obj=obj@entry=0x0)
1 qio_channel_readv_full (ioc=0x0, iov=0x7ffe55277180 ...
2 qio_channel_read (ioc=<optimized out> ...
3 vnc_client_read_buf (vs=vs@entry=0x55625f3c6000, ...
4 vnc_client_read_plain (vs=0x55625f3c6000)
5 vnc_client_read (vs=0x55625f3c6000)
6 vnc_client_io (ioc=<optimized out>, condition=G_IO_IN, ...
7 g_main_dispatch (context=0x556251568a50)
8 g_main_context_dispatch (context=context@entry=0x556251568a50)
9 glib_pollfds_poll ()
10 os_host_main_loop_wait (timeout=<optimized out>)
11 main_loop_wait (nonblocking=nonblocking@entry=0)
12 main_loop () at vl.c:1909
13 main (argc=<optimized out>, argv=<optimized out>, ...
Having analyzed the coredump, I understood that the reason is that
ioc_tag is reset on vnc_disconnect_start and ioc is cleaned
in vnc_disconnect_finish. Between these two events due to some
reasons the ioc_tag was set again and after vnc_disconnect_finish
the handler is running with freed ioc,
which led to the segmentation fault.
The patch checks vs->disconnecting in places where we call
qio_channel_add_watch and resets handler if disconnecting == TRUE
to prevent such an occurrence.
Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20180207094844.21402-1-klim.kireev@virtuozzo.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
vnc_listen_io() does not own the reference on the 'cioc' parameter is it
passed, so should not be unref'ing it.
Fixes: 13e1d0e71e
Reported-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20180215102602.10864-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter. Drop the include, and add it
to the places that actually need it.
While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.
This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
qapi/qmp/types.h is a convenience header to include a number of
qapi/qmp/ headers. Since we rarely need all of the headers
qapi/qmp/types.h includes, we bypass it most of the time. Most of the
places that use it don't need all the headers, either.
Include the necessary headers directly, and drop qapi/qmp/types.h.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-9-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-6-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.
While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
The VNC server already has the ability to listen on multiple sockets.
Converting it to use the QIONetListener APIs though, will reduce the
amount of code in the VNC server and improve the clarity of what is
left.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20180201164514.10330-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Pixman returns a signed int for the image width/height, but the VNC
protocol only permits a unsigned int16. Effective framebuffer size
is determined by the guest, limited by the video RAM size, so the
dimensions are unlikely to exceed the range of an unsigned int16,
but this is not currently validated.
With the current use of 'int' for client width/height, the calculation
of offsets in vnc_update_throttle_offset() suffers from integer size
promotion and sign extension, causing coverity warnings
*** CID 1385147: Integer handling issues (SIGN_EXTENSION)
/ui/vnc.c: 979 in vnc_update_throttle_offset()
973 * than that the client would already suffering awful audio
974 * glitches, so dropping samples is no worse really).
975 */
976 static void vnc_update_throttle_offset(VncState *vs)
977 {
978 size_t offset =
>>> CID 1385147: Integer handling issues (SIGN_EXTENSION)
>>> Suspicious implicit sign extension:
"vs->client_pf.bytes_per_pixel" with type "unsigned char" (8 bits,
unsigned) is promoted in "vs->client_width * vs->client_height *
vs->client_pf.bytes_per_pixel" to type "int" (32 bits, signed), then
sign-extended to type "unsigned long" (64 bits, unsigned). If
"vs->client_width * vs->client_height * vs->client_pf.bytes_per_pixel"
is greater than 0x7FFFFFFF, the upper bits of the result will all be 1.
979 vs->client_width * vs->client_height * vs->client_pf.bytes_per_pixel;
Change client_width / client_height to be a size_t to avoid sign
extension and integer promotion. Then validate that dimensions are in
range wrt the RFB protocol u16 limits.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20180118155254.17053-1-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
While the QIOChannel APIs for reading/writing data return ssize_t, with negative
value indicating an error, the VNC code passes this return value through the
vnc_client_io_error() method. This detects the error condition, disconnects the
client and returns 0 to indicate error. Thus all the VNC helper methods should
return size_t (unsigned), and misleading comments which refer to the possibility
of negative return values need fixing.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-14-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC client throttling is quite subtle so will benefit from having trace
points available for live debugging.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-13-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The previous patches fix problems with throttling of forced framebuffer updates
and audio data capture that would cause the QEMU output buffer size to grow
without bound. Those fixes are graceful in that once the client catches up with
reading data from the server, everything continues operating normally.
There is some data which the server sends to the client that is impractical to
throttle. Specifically there are various pseudo framebuffer update encodings to
inform the client of things like desktop resizes, pointer changes, audio
playback start/stop, LED state and so on. These generally only involve sending
a very small amount of data to the client, but a malicious guest might be able
to do things that trigger these changes at a very high rate. Throttling them is
not practical as missed or delayed events would cause broken behaviour for the
client.
This patch thus takes a more forceful approach of setting an absolute upper
bound on the amount of data we permit to be present in the output buffer at
any time. The previous patch set a threshold for throttling the output buffer
by allowing an amount of data equivalent to one complete framebuffer update and
one seconds worth of audio data. On top of this it allowed for one further
forced framebuffer update to be queued.
To be conservative, we thus take that throttling threshold and multiply it by
5 to form an absolute upper bound. If this bound is hit during vnc_write() we
forceably disconnect the client, refusing to queue further data. This limit is
high enough that it should never be hit unless a malicious client is trying to
exploit the sever, or the network is completely saturated preventing any sending
of data on the socket.
This completes the fix for CVE-2017-15124 started in the previous patches.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-12-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC server must throttle data sent to the client to prevent the 'output'
buffer size growing without bound, if the client stops reading data off the
socket (either maliciously or due to stalled/slow network connection).
The current throttling is very crude because it simply checks whether the
output buffer offset is zero. This check is disabled if the client has requested
a forced update, because we want to send these as soon as possible.
As a result, the VNC client can cause QEMU to allocate arbitrary amounts of RAM.
They can first start something in the guest that triggers lots of framebuffer
updates eg play a youtube video. Then repeatedly send full framebuffer update
requests, but never read data back from the server. This can easily make QEMU's
VNC server send buffer consume 100MB of RAM per second, until the OOM killer
starts reaping processes (hopefully the rogue QEMU process, but it might pick
others...).
To address this we make the throttling more intelligent, so we can throttle
full updates. When we get a forced update request, we keep track of exactly how
much data we put on the output buffer. We will not process a subsequent forced
update request until this data has been fully sent on the wire. We always allow
one forced update request to be in flight, regardless of what data is queued
for incremental updates or audio data. The slight complication is that we do
not initially know how much data an update will send, as this is done in the
background by the VNC job thread. So we must track the fact that the job thread
has an update pending, and not process any further updates until this job is
has been completed & put data on the output buffer.
This unbounded memory growth affects all VNC server configurations supported by
QEMU, with no workaround possible. The mitigating factor is that it can only be
triggered by a client that has authenticated with the VNC server, and who is
able to trigger a large quantity of framebuffer updates or audio samples from
the guest OS. Mostly they'll just succeed in getting the OOM killer to kill
their own QEMU process, but its possible other processes can get taken out as
collateral damage.
This is a more general variant of the similar unbounded memory usage flaw in
the websockets server, that was previously assigned CVE-2017-15268, and fixed
in 2.11 by:
commit a7b20a8efa
Author: Daniel P. Berrange <berrange@redhat.com>
Date: Mon Oct 9 14:43:42 2017 +0100
io: monitor encoutput buffer size from websocket GSource
This new general memory usage flaw has been assigned CVE-2017-15124, and is
partially fixed by this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-11-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The VNC server must throttle data sent to the client to prevent the 'output'
buffer size growing without bound, if the client stops reading data off the
socket (either maliciously or due to stalled/slow network connection).
The current throttling is very crude because it simply checks whether the
output buffer offset is zero. This check must be disabled if audio capture is
enabled, because when streaming audio the output buffer offset will rarely be
zero due to queued audio data, and so this would starve framebuffer updates.
As a result, the VNC client can cause QEMU to allocate arbitrary amounts of RAM.
They can first start something in the guest that triggers lots of framebuffer
updates eg play a youtube video. Then enable audio capture, and simply never
read data back from the server. This can easily make QEMU's VNC server send
buffer consume 100MB of RAM per second, until the OOM killer starts reaping
processes (hopefully the rogue QEMU process, but it might pick others...).
To address this we make the throttling more intelligent, so we can throttle
when audio capture is active too. To determine how to throttle incremental
updates or audio data, we calculate a size threshold. Normally the threshold is
the approximate number of bytes associated with a single complete framebuffer
update. ie width * height * bytes per pixel. We'll send incremental updates
until we hit this threshold, at which point we'll stop sending updates until
data has been written to the wire, causing the output buffer offset to fall
back below the threshold.
If audio capture is enabled, we increase the size of the threshold to also
allow for upto 1 seconds worth of audio data samples. ie nchannels * bytes
per sample * frequency. This allows the output buffer to have a mixture of
incremental framebuffer updates and audio data queued, but once the threshold
is exceeded, audio data will be dropped and incremental updates will be
throttled.
This unbounded memory growth affects all VNC server configurations supported by
QEMU, with no workaround possible. The mitigating factor is that it can only be
triggered by a client that has authenticated with the VNC server, and who is
able to trigger a large quantity of framebuffer updates or audio samples from
the guest OS. Mostly they'll just succeed in getting the OOM killer to kill
their own QEMU process, but its possible other processes can get taken out as
collateral damage.
This is a more general variant of the similar unbounded memory usage flaw in
the websockets server, that was previously assigned CVE-2017-15268, and fixed
in 2.11 by:
commit a7b20a8efa
Author: Daniel P. Berrange <berrange@redhat.com>
Date: Mon Oct 9 14:43:42 2017 +0100
io: monitor encoutput buffer size from websocket GSource
This new general memory usage flaw has been assigned CVE-2017-15124, and is
partially fixed by this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-10-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The logic for determining if it is possible to send an update to the client
will become more complicated shortly, so pull it out into a separate method
for easier extension later.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-9-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
According to the RFB protocol, a client sends one or more framebuffer update
requests to the server. The server can reply with a single framebuffer update
response, that covers all previously received requests. Once the client has
read this update from the server, it may send further framebuffer update
requests to monitor future changes. The client is free to delay sending the
framebuffer update request if it needs to throttle the amount of data it is
reading from the server.
The QEMU VNC server, however, has never correctly handled the framebuffer
update requests. Once QEMU has received an update request, it will continue to
send client updates forever, even if the client hasn't asked for further
updates. This prevents the client from throttling back data it gets from the
server. This change fixes the flawed logic such that after a set of updates are
sent out, QEMU waits for a further update request before sending more data.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-8-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Currently the VNC servers tracks whether a client has requested an incremental
or forced update with two boolean flags. There are only really 3 distinct
states to track, so create an enum to more accurately reflect permitted states.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-7-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The vnc_update_client() method checks the 'has_dirty' flag to see if there are
dirty regions that are pending to send to the client. Regardless of this flag,
if a forced update is requested, updates must be sent. For unknown reasons
though, the code also tries to sent updates if audio capture is enabled. This
makes no sense as audio capture state does not impact framebuffer contents, so
this check is removed.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-5-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Now that previous dead / unreachable code has been removed, we can simplify
the indentation in the vnc_client_update method.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-4-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
A previous commit:
commit 5a8be0f73d
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Wed Jul 13 12:21:20 2016 +0200
vnc: make sure we finish disconnect
Added a check for vs->disconnecting at the very start of the
vnc_update_client method. This means that the very next "if"
statement check for !vs->disconnecting always evaluates true,
and is thus redundant. This in turn means the vs->disconnecting
check at the very end of the method never evaluates true, and
is thus unreachable code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There is only one caller of vnc_update_client and that always passes false
for the 'sync' parameter.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20171218191228.31018-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Also set saved handle to zero when removing without adding a new watch.
Signed-off-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Trace anything related to authentication in the VNC protocol
handshake
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170921121528.23935-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Trace anything which opens/closes/wraps a QIOChannel in the
VNC server.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170921121528.23935-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Extract the (correct) cleaning code as a new function vnc_free_addresses() then
use it to remove the memory leaks.
Reported-by: Clang Static Analyzer
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The current VNC default keyboard delay is 1ms. With that we're constantly
typing faster than the guest receives keyboard events from an XHCI attached
USB HID device.
The default keyboard delay time in the input layer however is 10ms. I don't know
how that number came to be, but empirical tests on some OpenQA driven ARM
systems show that 10ms really is a reasonable default number for the delay.
This patch moves the VNC delay also to 10ms. That way our default is much
safer (good!) and also consistent with the input layer default (also good!).
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1499863425-103133-1-git-send-email-agraf@suse.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Looks like #include "hw/qdev.h" is not needed here, so remove it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-id: 1497894617-12143-1-git-send-email-thuth@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ctpopl() has a better implementation than hweight_long() and ui/vnc.c
being the last user of hweight_long(), we can simply remove it.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1489415605-13105-1-git-send-email-clg@kaod.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch refactors ui/input.c to support absolute axis
minimum values other than 0. All dependent calls to qemu_input_queue_abs
have been updated to explicitly supply 0 as the axis minimum value.
Signed-off-by: Philippe Voinov <philippevoinov@gmail.com>
Message-id: 20170505133952.29885-1-philippevoinov@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
SocketAddressLegacy is a simple union, and simple unions are awkward:
they have their variant members wrapped in a "data" object on the
wire, and require additional indirections in C. SocketAddress is the
equivalent flat union. Convert all users of SocketAddressLegacy to
SocketAddress, except for existing external interfaces.
See also commit fce5d53..9445673 and 85a82e8..c5f1ae3.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-7-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Minor editing accident fixed, commit message and a comment tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next commit will rename SocketAddressFlat to SocketAddress, and
the commit after that will replace most uses of SocketAddressLegacy by
SocketAddress, replacing most of this commit's renames right back.
Note that checkpatch emits a few "line over 80 characters" warnings.
The long lines are all temporary; the SocketAddressLegacy replacement
will shorten them again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We have quite a few switches over SocketAddressKind. Some have case
labels for all enumeration values, others rely on a default label.
Some abort when the value isn't a valid SocketAddressKind, others
report an error then.
Unify as follows. Always provide case labels for all enumeration
values, to clarify intent. Abort when the value isn't a valid
SocketAddressKind, because the program state is messed up then.
Improve a few error messages while there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1490895797-29094-4-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Certain features make sense only with certain address families. For
instance, passing file descriptors requires AF_UNIX. Testing
SocketAddress's saddr->type == SOCKET_ADDRESS_KIND_UNIX is obvious,
but problematic: it can't recognize AF_UNIX when type ==
SOCKET_ADDRESS_KIND_FD.
Mark such tests of saddr->type TODO. We may want to check the address
family with getsockname() there.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1490895797-29094-2-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
vnc server in reverse mode (qemu -vnc localhost:$nr,reverse) interprets
$nr as display number (i.e. with 5900 offset) in recent qemu versions.
Historical and documented behavior is interpreting $nr as port number
though. So we should bring code and documentation in line.
Given that default listening port for viewers is 5500 the 5900 offset is
pretty inconvinient, because it is simply impossible to connect to port
5500. So, lets fix the code not the docs.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1489480018-11443-1-git-send-email-kraxel@redhat.com
There is a special code path (dpy_gfx_copy) to allow graphic emulation
notify user interface code about bitblit operations carryed out by
guests. It is supported by cirrus and vnc server. The intended purpose
is to optimize display scrolls and just send over the scroll op instead
of a full display update.
This is rarely used these days though because modern guests simply don't
use the cirrus blitter any more. Any linux guest using the cirrus drm
driver doesn't. Any windows guest newer than winxp doesn't ship with a
cirrus driver any more and thus uses the cirrus as simple framebuffer.
So this code tends to bitrot and bugs can go unnoticed for a long time.
See for example commit "3e10c3e vnc: fix qemu crash because of SIGSEGV"
which fixes a bug lingering in the code for almost a year, added by
commit "c7628bf vnc: only alloc server surface with clients connected".
Also the vnc server will throttle the frame rate in case it figures the
network can't keep up (send buffers are full). This doesn't work with
dpy_gfx_copy, for any copy operation sent to the vnc client we have to
send all outstanding updates beforehand, otherwise the vnc client might
run the client side blit on outdated data and thereby corrupt the
display. So this dpy_gfx_copy "optimization" might even make things
worse on slow network links.
Lets kill it once for all.
Oh, and one more reason: Turns out (after writing the patch) we have a
security bug in that code path ...
Fixes: CVE-2016-9603
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1489494419-14340-1-git-send-email-kraxel@redhat.com
This change allows the listen address and websocket address
options for -vnc to be repeated. This causes the VNC server
to listen on multiple addresses. e.g.
$ $QEMU -vnc vnc=localhost:1,vnc=unix:/tmp/vnc,\
websocket=127.0.0.1:8080,websocket=[::]:8081
results in listening on
127.0.0.1:5901, 127.0.0.1:8080, ::1:5901, :::8081 & /tmp/vnc
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-9-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Remove the limitation that the VNC server can only listen on
a single resolved IP address. This uses the new DNS resolver
API to resolve a SocketAddress struct into an array of
SocketAddress structs containing raw IP addresses. The VNC
server will then attempt to listen on all resolved IP addresses.
The server must successfully listen on at least one of the
resolved IP addresses, otherwise an error will be reported.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-7-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The code which takes a SocketAddress and connects/listens on the
network is going to get more complicated to deal with multiple
listeners. Pull it out into a separate method to avoid making the
vnc_display_open method even more complex.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-6-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The code which interprets the CLI args to populate the SocketAddress
objects for plain & websockets VNC is quite complex already and will
need further enhancements shortly. Refactor it into separate methods
to avoid vnc_display_open getting even larger. As a side effect of
the refactoring, it is now possible to specify a listen address for
the websocket server explicitly. e.g,
-vnc localhost:5900,websockets=0.0.0.0:8080
will listen on localhost for the plain VNC server, but expose the
websockets VNC server on the public interface. This refactoring
also removes the restriction that prevents enabling websockets
when the plain VNC server is listening on a UNIX socket.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-5-berrange@redhat.com
[ kraxel: squashed clang build fix ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Currently there is only a single listener for plain VNC and
a single listener for websockets VNC. This means that if
getaddrinfo() returns multiple IP addresses, for a hostname,
the VNC server can only listen on one of them. This is
just bearable if listening on wildcard interface, or if
the host only has a single network interface to listen on,
but if there are multiple NICs and the VNC server needs
to listen on 2 or more specific IP addresses, it can't be
done.
This refactors the VncDisplay state so that it holds an
array of listening sockets, but still only listens on
one socket.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-4-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Currently the VNC authentication info is emitted at the
top level of the query-vnc-servers data. This is wrong
because the authentication scheme differs between plain
and websockets when TLS is enabled. We should instead
report auth against the individual servers. e.g.
(QEMU) query-vnc-servers
{
"return": [
{
"clients": [],
"id": "default",
"auth": "vencrypt",
"vencrypt": "x509-vnc",
"server": [
{
"host": "127.0.0.1"
"service": "5901",
"websocket": false,
"family": "ipv4",
"auth": "vencrypt",
"vencrypt": "x509-vnc"
},
{
"host": "127.0.0.1",
"service": "5902",
"websocket": true,
"family": "ipv4",
"auth": "vnc"
}
]
}
]
}
This also future proofs the QMP schema so that we can
cope with multiple VNC server instances, listening on
different interfaces or ports, with different auth
setup.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The -vnc argument is documented as accepting two syntaxes for
the 'websocket' option, either a bare option name, or a port
number. If using the bare option name, it is supposed to apply
the display number as an offset to base port 5700. e.g.
-vnc localhost:3,websocket
should listen on port 5703, however, this was broken in 2.3.0 since
commit 4db14629c3
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue Sep 16 12:33:03 2014 +0200
vnc: switch to QemuOpts, allow multiple servers
instead qemu tries to listen on port "on" which gets looked up in
/etc/services and fails.
Fixes bug: #1455912
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170203120649.15637-2-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
When qemu vnc server is trying to send large update to clients,
there might be a situation when system responds with something
like EAGAIN, indicating that there's no system memory to send
that much data (depending on the network speed, client and server
and what is happening). In this case, something like this happens
on qemu side (from strace):
sendmsg(16, {msg_name(0)=NULL,
msg_iov(1)=[{"\244\"..., 729186}],
msg_controllen=0, msg_flags=0}, 0) = 103950
sendmsg(16, {msg_name(0)=NULL,
msg_iov(1)=[{"lz\346"..., 1559618}],
msg_controllen=0, msg_flags=0}, 0) = -1 EAGAIN
sendmsg(-1, {msg_name(0)=NULL,
msg_iov(1)=[{"lz\346"..., 1559618}],
msg_controllen=0, msg_flags=0}, 0) = -1 EBADF
qemu closes the socket before the retry, and obviously it gets EBADF
when trying to send to -1.
This is because there WAS a special handling for EAGAIN, but now it doesn't
work anymore, after commit 04d2529da2, because
now in all error-like cases we initiate vnc disconnect.
This change were introduced in qemu 2.6, and caused numerous grief for many
people, resulting in their vnc clients reporting sporadic random disconnects
from vnc server.
Fix that by doing the disconnect only when necessary, i.e. omitting this
very case of EAGAIN.
Hopefully the existing condition (comparing with QIO_CHANNEL_ERR_BLOCK)
is sufficient, as the original code (before the above commit) were
checking for other errno values too.
Apparently there's another (semi?)bug exist somewhere here, since the
code tries to write to fd# -1, it probably should check if the connection
is open before. But this isn't important.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1486115549-9398-1-git-send-email-mjt@msgid.tls.msk.ru
Fixes: 04d2529da2
Cc: Daniel P. Berrange <berrange@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Commit "bea60dd ui/vnc: fix potential memory corruption issues" is
incomplete. vnc_update_stats must calculate width and height the same
way vnc_refresh_server_surface does it, to make sure we don't use width
and height values larger than the qemu vnc server can handle.
Commit "e22492d ui/vnc: disable adaptive update calculations if not
needed" masks the issue in the default configuration. It triggers only
in case the "lossy" option is set to "on" (default is "off").
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1485248428-575-1-git-send-email-kraxel@redhat.com
When building qemu after setting _VNC_DEBUG to 1 (see ui/vnc.h),
we get the following error and the build breaks:
...
ui/vnc.c: In function ‘vnc_client_io_error’:
ui/vnc.c:1262:13: error: format ‘%d’ expects argument of type ‘int’, but
VNC_DEBUG("Closing down client sock: ret %d (%s)\n",
^
cc1: all warnings being treated as errors
make: *** [ui/vnc.o] Error 1
...
This patch solves this issue by fixing the print format specifier
in vnc_client_io_error() to be %zd, which corresponds to the type
of the "ret" variable.
Signed-off-by: Rami Rosen <rami.rosen@intel.com>
Message-id: 1484039965-25907-1-git-send-email-rami.rosen@intel.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
If the buffer is not big enough, snprintf() does not return the number
of bytes that have been written to the buffer, but the number of bytes
that would be needed for writing the whole string. By using this value
for the following vnc_write() calls, we send some junk at the end of
the name in case the qemu_name is longer than 1017 bytes, which could
confuse the VNC clients. Fix this by adding an additional size check
here.
Buglink: https://bugs.launchpad.net/qemu/+bug/1637447
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1479749115-21932-1-git-send-email-thuth@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Ensure that all I/O channels created for VNC are given names
to distinguish their respective roles.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It can't guarantee all cipher modes are supported
if one cipher algorithm is supported by a backend.
Let's extend qcrypto_cipher_supports() to take both
the algorithm and mode as parameters.
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Rename the vnc_init_state method to reflect what its actual
purpose is, to discourage future devs from using it for more
general state initialization.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-10-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Most of the fields in VncState are initialized in the
vnc_connect() method, but some are done in vnc_init_state()
instead.
The purpose of having vnc_init_state() is to delay starting
of the VNC wire protocol until after the websockets handshake
has completed. As such the vnc_init_state() method only needs
to be used for initialization that is dependant on the wire
protocol running.
This also lets us get rid of the initialized boolean flag
from the VncState struct.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-9-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The vnc_init_state method calls reset_keys() to reset the
modifier key state. This was originally added in
commit 53762ddb27
Author: malc <malc@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Mon Dec 1 20:57:52 2008 +0000
Reset the key modifiers upon client connect
This was valid at this time because there was only the
single VncState object which was persistent across client
connections and so needed resetting.
The persistent data was later split off into VncDisplay
and VncState was allocated at time of client connection:
commit 753b405331
Author: aliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Mon Feb 16 14:59:30 2009 +0000
Support multiple VNC clients (Brian Kress)
at which point the modifier state is always 0 due to
use of g_new0. As such the reset_keys() call has been
a no-op ever since.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-8-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Just before accepting a new client connection the vnc_listen_io
method calls graphic_hw_update(). This is bogus because there
is a call to this method already in vnc_state_init() and the
client doesn't need up2date graphics console before reaching
that.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-7-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There is a lot of repeated code in the auth type setup method,
particularly around checking TLS credential types. Refactor
it to reduce duplication and instead of having one method
do both plain and websockets at once, call it separately
for each.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-6-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Normally code declares 'VncDisplay *vd' or 'VncState *vs'
but there are a bunch of places which misleadingly declare
'VncDisplay *vs'.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-5-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The 'ws_tls' field in VncState is only ever representing
the result of 'tlscreds != NULL' and is thus pointless.
Replace use of 'ws_tls' with a direct check against
'tlscreds'
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-4-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The 'ws_enabled' field is never used outside of the
vnc_display_open method, so can be a local variable.
The 'enabled' field is easily replaced by a check
for whether 'lsock' is non-NULL.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-3-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The last line in vnc_init_state() says
/* vs might be free()ed here */
This was added in
commit 198a0039c5
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Tue Jun 16 14:19:48 2009 +0200
vnc: rework VncState release workflow.
because the preceeding 'vnc_update_client()' could indeed
release the VncState instance.
The call to vnc_update_client() was removed not long after
though in
commit 1fc624122f
Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date: Mon Aug 3 10:54:32 2009 +0100
single vnc server surface
and so the comment has been wrong ever since
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475163940-26094-2-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
In previous commit
commit c7628bff41
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri Oct 30 12:10:09 2015 +0100
vnc: only alloc server surface with clients connected
the VNC server was changed so that the 'vd->server' pixman
image was only allocated when a client is connected.
Since then if a client disconnects and then reconnects to
the VNC server all they will see is a black screen until
they do something that triggers a refresh. On a graphical
desktop this is not often noticed since there's many things
going on which cause a refresh. On a plain text console it
is really obvious since nothing refreshes frequently.
The problem is that the VNC server didn't update the guest
dirty bitmap, so still believes its server image is in sync
with the guest contents.
To fix this we must explicitly mark the entire guest desktop
as dirty after re-creating the server surface. Move this
logic into vnc_update_server_surface() so it is guaranteed
to be call in all code paths that re-create the surface
instead of only in vnc_dpy_switch()
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Tested-by: Peter Lieven <pl@kamp.de>
Message-id: 1471365032-18096-1-git-send-email-berrange@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1470224274-31522-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The connection sharing / limits are only set in the
vnc_display_open() method and so missed when VNC is running
with '-vnc none'. This in turn prevents clients being added
to the VNC server with the QMP "add_client" command.
This was introduced in
commit e5f34cdd2d
Author: Gerd Hoffmann <kraxel@redhat.com>
Date: Thu Oct 2 12:09:34 2014 +0200
vnc: track & limit connections
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1470134726-15697-4-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The vnc_server_info_get will allocate the VncServerInfo
struct and then call vnc_init_basic_info_from_server_addr
to populate the basic fields. If this returns an error
though, the qapi_free_VncServerInfo call will then crash
because the VncServerInfo struct instance was not properly
NULL-initialized and thus contains random stack garbage.
#0 0x00007f1987c8e6f5 in raise () at /lib64/libc.so.6
#1 0x00007f1987c902fa in abort () at /lib64/libc.so.6
#2 0x00007f1987ccf600 in __libc_message () at /lib64/libc.so.6
#3 0x00007f1987cd7d4a in _int_free () at /lib64/libc.so.6
#4 0x00007f1987cdb2ac in free () at /lib64/libc.so.6
#5 0x00007f198b654f6e in g_free () at /lib64/libglib-2.0.so.0
#6 0x0000559193cdcf54 in visit_type_str (v=v@entry=
0x5591972f14b0, name=name@entry=0x559193de1e29 "host", obj=obj@entry=0x5591961dbfa0, errp=errp@entry=0x7fffd7899d80)
at qapi/qapi-visit-core.c:255
#7 0x0000559193cca8f3 in visit_type_VncBasicInfo_members (v=v@entry=
0x5591972f14b0, obj=obj@entry=0x5591961dbfa0, errp=errp@entry=0x7fffd7899dc0) at qapi-visit.c:12307
#8 0x0000559193ccb523 in visit_type_VncServerInfo_members (v=v@entry=
0x5591972f14b0, obj=0x5591961dbfa0, errp=errp@entry=0x7fffd7899e00) at qapi-visit.c:12632
#9 0x0000559193ccb60b in visit_type_VncServerInfo (v=v@entry=
0x5591972f14b0, name=name@entry=0x0, obj=obj@entry=0x7fffd7899e48, errp=errp@entry=0x0) at qapi-visit.c:12658
#10 0x0000559193cb53d8 in qapi_free_VncServerInfo (obj=<optimized out>) at qapi-types.c:3970
#11 0x0000559193c1e6ba in vnc_server_info_get (vd=0x7f1951498010) at ui/vnc.c:233
#12 0x0000559193c24275 in vnc_connect (vs=0x559197b2f200, vs=0x559197b2f200, event=QAPI_EVENT_VNC_CONNECTED) at ui/vnc.c:284
#13 0x0000559193c24275 in vnc_connect (vd=vd@entry=0x7f1951498010, sioc=sioc@entry=0x559196bf9c00, skipauth=skipauth@entry=tru e, websocket=websocket@entry=false) at ui/vnc.c:3039
#14 0x0000559193c25806 in vnc_display_add_client (id=<optimized out>, csock=<optimized out>, skipauth=<optimized out>)
at ui/vnc.c:3877
#15 0x0000559193a90c28 in qmp_marshal_add_client (args=<optimized out>, ret=<optimized out>, errp=0x7fffd7899f90)
at qmp-marshal.c:105
#16 0x000055919399c2b7 in handle_qmp_command (parser=<optimized out>, tokens=<optimized out>)
at /home/berrange/src/virt/qemu/monitor.c:3971
#17 0x0000559193ce3307 in json_message_process_token (lexer=0x559194ab0838, input=0x559194a6d940, type=JSON_RCURLY, x=111, y=1 2) at qobject/json-streamer.c:105
#18 0x0000559193cfa90d in json_lexer_feed_char (lexer=lexer@entry=0x559194ab0838, ch=125 '}', flush=flush@entry=false)
at qobject/json-lexer.c:319
#19 0x0000559193cfaa1e in json_lexer_feed (lexer=0x559194ab0838, buffer=<optimized out>, size=<optimized out>)
at qobject/json-lexer.c:369
#20 0x0000559193ce33c9 in json_message_parser_feed (parser=<optimized out>, buffer=<optimized out>, size=<optimized out>)
at qobject/json-streamer.c:124
#21 0x000055919399a85b in monitor_qmp_read (opaque=<optimized out>, buf=<optimized out>, size=<optimized out>)
at /home/berrange/src/virt/qemu/monitor.c:3987
#22 0x0000559193a87d00 in tcp_chr_read (chan=<optimized out>, cond=<optimized out>, opaque=0x559194a7d900)
at qemu-char.c:2895
#23 0x00007f198b64f703 in g_main_context_dispatch () at /lib64/libglib-2.0.so.0
#24 0x0000559193c484b3 in main_loop_wait () at main-loop.c:213
#25 0x0000559193c484b3 in main_loop_wait (timeout=<optimized out>) at main-loop.c:258
#26 0x0000559193c484b3 in main_loop_wait (nonblocking=<optimized out>) at main-loop.c:506
#27 0x0000559193964c55 in main () at vl.c:1908
#28 0x0000559193964c55 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4603
This was introduced in
commit 98481bfcd6
Author: Eric Blake <eblake@redhat.com>
Date: Mon Oct 26 16:34:45 2015 -0600
vnc: Hoist allocation of VncBasicInfo to callers
which added error reporting for vnc_init_basic_info_from_server_addr
but didn't change the g_malloc calls to g_malloc0.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1470134726-15697-3-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
When VNC is started with '-vnc none' there will be no
listener socket present. When we try to populate the
VncServerInfo we'll crash accessing a NULL 'lsock'
field.
#0 qio_channel_socket_get_local_address (ioc=0x0, errp=errp@entry=0x7ffd5b8aa0f0) at io/channel-socket.c:33
#1 0x00007f4b9a297d6f in vnc_init_basic_info_from_server_addr (errp=0x7ffd5b8aa0f0, info=0x7f4b9d425460, ioc=<optimized out>) at ui/vnc.c:146
#2 vnc_server_info_get (vd=0x7f4b9e858000) at ui/vnc.c:223
#3 0x00007f4b9a29d318 in vnc_qmp_event (vs=0x7f4b9ef82000, vs=0x7f4b9ef82000, event=QAPI_EVENT_VNC_CONNECTED) at ui/vnc.c:279
#4 vnc_connect (vd=vd@entry=0x7f4b9e858000, sioc=sioc@entry=0x7f4b9e8b3a20, skipauth=skipauth@entry=true, websocket=websocket @entry=false) at ui/vnc.c:2994
#5 0x00007f4b9a29e8c8 in vnc_display_add_client (id=<optimized out>, csock=<optimized out>, skipauth=<optimized out>) at ui/v nc.c:3825
#6 0x00007f4b9a18d8a1 in qmp_marshal_add_client (args=<optimized out>, ret=<optimized out>, errp=0x7ffd5b8aa230) at qmp-marsh al.c:123
#7 0x00007f4b9a0b53f5 in handle_qmp_command (parser=<optimized out>, tokens=<optimized out>) at /usr/src/debug/qemu-2.6.0/mon itor.c:3922
#8 0x00007f4b9a348580 in json_message_process_token (lexer=0x7f4b9c78dfe8, input=0x7f4b9c7350e0, type=JSON_RCURLY, x=111, y=5 9) at qobject/json-streamer.c:94
#9 0x00007f4b9a35cfeb in json_lexer_feed_char (lexer=lexer@entry=0x7f4b9c78dfe8, ch=125 '}', flush=flush@entry=false) at qobj ect/json-lexer.c:310
#10 0x00007f4b9a35d0ae in json_lexer_feed (lexer=0x7f4b9c78dfe8, buffer=<optimized out>, size=<optimized out>) at qobject/json -lexer.c:360
#11 0x00007f4b9a348679 in json_message_parser_feed (parser=<optimized out>, buffer=<optimized out>, size=<optimized out>) at q object/json-streamer.c:114
#12 0x00007f4b9a0b3a1b in monitor_qmp_read (opaque=<optimized out>, buf=<optimized out>, size=<optimized out>) at /usr/src/deb ug/qemu-2.6.0/monitor.c:3938
#13 0x00007f4b9a186751 in tcp_chr_read (chan=<optimized out>, cond=<optimized out>, opaque=0x7f4b9c7add40) at qemu-char.c:2895
#14 0x00007f4b92b5c79a in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#15 0x00007f4b9a2bb0c0 in glib_pollfds_poll () at main-loop.c:213
#16 os_host_main_loop_wait (timeout=<optimized out>) at main-loop.c:258
#17 main_loop_wait (nonblocking=<optimized out>) at main-loop.c:506
#18 0x00007f4b9a0835cf in main_loop () at vl.c:1934
#19 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4667
Do an upfront check for a NULL lsock and report an error to
the caller, which matches behaviour from before
commit 04d2529da2
Author: Daniel P. Berrange <berrange@redhat.com>
Date: Fri Feb 27 16:20:57 2015 +0000
ui: convert VNC server to use QIOChannelSocket
where getsockname() would be given a FD value -1 and thus report
an error to the caller.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1470134726-15697-2-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
It may happen that vnc connections linger in disconnecting state forever
because VncState happens to be in a state where vnc_update_client()
exists early and never reaches the vnc_disconnect_finish() call at the
bottom of the function. Fix that by doing an additinal check at the
start of the function.
https://bugzilla.redhat.com/show_bug.cgi?id=1352799
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1468405280-2571-1-git-send-email-kraxel@redhat.com
The vnc_client_read() function is called from the vnc_client_io()
event handler callback when there is incoming data to process.
If it detects that the client has disconnected, then it will
trigger cleanup and free'ing of the VncState client struct at
a safe time.
Unfortunately, the vnc_client_io() event handler will also call
vnc_client_write() to handle any outgoing data writes. So if
vnc_client_io() was invoked with both G_IO_IN and G_IO_OUT
events set, and the client disconnects, we may try to write to
a client which has just been freed.
https://bugs.launchpad.net/qemu/+bug/1594861
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1467042529-3372-1-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
vs->disconnecting is set to TRUE and vs->ioc is closed, but
vs->ioc isn't set to NULL, so that the vnc_disconnect_finish()
isn't invoked when you update client in vnc_update_client()
after vnc_disconnect_start invoked. Let's using change the checking
condition to avoid resource leak.
Signed-off-by: Haibin Wang <wanghaibin.wang@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1467949056-81208-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
If VNC is chosen as the compile time default display backend,
QEMU will print the host/port it listens on at startup.
Previously this would look like
VNC server running on '::1:5900'
but in 04d2529da2 the ':' was
accidentally replaced with a ';'. This the ':' back.
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1465382576-25552-1-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Limits the rate kbd events from the vnc server are forwarded to the
guest, so input devices which are typically low-bandwidth can keep
up even on bulky input.
v2: update documentation too.
v3: spell fixes.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Yang Hongyang <hongyang.yang@easystack.cn>
Message-id: 1464762150-25817-1-git-send-email-kraxel@redhat.com
Our current VNC code does not handle color maps (aka non-true-color) at all
and aborts if a client requests them. There are 2 major issues with this:
1) A VNC viewer on an 8-bit X11 system may request color maps
2) RealVNC _always_ starts requesting color maps, then moves on to full color
In order to support these 2 use cases, let's just create a fake color map
that covers exactly our normal true color 8 bit color space. That way we don't
lose anything over a client that wants true color.
Reported-by: Sascha Wehnert <swehnert@suse.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1464099559-20789-1-git-send-email-den@openvz.org
Actually this is a very old patch originally submitted in 2013 by
Alexander. The situation is still the same with RealVNC, it does not
connect by default to QEMU VNC. The problem is that this client is
really popular. This is better to be kludged.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gerd Hoffmann <kraxel@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Gerd Hoffmann
Daniel P. Berrange
Markus Armbruster
Paolo Bonzini
Fei Li
Marc-André Lureau
Peter Xu
Philippe Mathieu-Daudé
Klim Kireev
Brandon Carpenter
Alexander Graf
Thomas Huth
Cédric Le Goater
Philippe Voinov
Michael Tokarev
Rami Rosen
Pierre Ossman
Gonglei