The most common use of -net tap is to connect a tap device to a bridge. This
requires the use of a script and running qemu as root in order to allocate a
tap device to pass to the script.
This model is great for portability and flexibility but it's incredibly
difficult to eliminate the need to run qemu as root. The only really viable
mechanism is to use tunctl to create a tap device, attach it to a bridge as
root, and then hand that tap device to qemu. The problem with this mechanism
is that it requires administrator intervention whenever a user wants to create
a guest.
By essentially writing a helper that implements the most common qemu-ifup
script that can be safely given cap_net_admin, we can dramatically simplify
things for non-privileged users. We still support existing -net tap options
as a mechanism for advanced users and backwards compatibility.
Currently, this is very Linux centric but there's really no reason why it
couldn't be extended for other Unixes.
A typical invocation would be similar to one of the following:
qemu linux.img -net bridge -net nic,model=virtio
qemu linux.img -net tap,helper="/usr/local/libexec/qemu-bridge-helper"
-net nic,model=virtio
qemu linux.img -netdev bridge,id=hn0
-device virtio-net-pci,netdev=hn0,id=nic1
qemu linux.img -netdev tap,helper="/usr/local/libexec/qemu-bridge-helper",id=hn0
-device virtio-net-pci,netdev=hn0,id=nic1
The default bridge that we attach to is br0. The thinking is that a distro
could preconfigure such an interface to allow out-of-the-box bridged networking.
Alternatively, if a user wants to use a different bridge, a typical invocation
would be simliar to one of the following:
qemu linux.img -net bridge,br=qemubr0 -net nic,model=virtio
qemu linux.img -net tap,helper="/usr/local/libexec/qemu-bridge-helper --br=qemubr0"
-net nic,model=virtio
qemu linux.img -netdev bridge,br=qemubr0,id=hn0
-device virtio-net-pci,netdev=hn0,id=nic1
qemu linux.img -netdev tap,helper="/usr/local/libexec/qemu-bridge-helper --br=qemubr0",id=hn0
-device virtio-net-pci,netdev=hn0,id=nic1
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Richa Marwaha <rmarwah@linux.vnet.ibm.com>
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The ideal way to use qemu-bridge-helper is to give it an fscap of using:
setcap cap_net_admin=ep qemu-bridge-helper
Unfortunately, most distros still do not have a mechanism to package files
with fscaps applied. This means they'll have to SUID the qemu-bridge-helper
binary.
To improve security, use libcap to reduce our capability set to just
cap_net_admin, then reduce privileges down to the calling user. This is
hopefully close to equivalent to fscap support from a security perspective.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Richa Marwaha <rmarwah@linux.vnet.ibm.com>
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We go to great lengths to restrict ourselves to just cap_net_admin as an OS
enforced security mechanism. However, we further restrict what we allow users
to do to simply adding a tap device to a bridge interface by virtue of the fact
that this is the only functionality we expose.
This is not good enough though. An administrator is likely to want to restrict
the bridges that an unprivileged user can access, in particular, to restrict
an unprivileged user from putting a guest on what should be isolated networks.
This patch implements an ACL mechanism that is enforced by qemu-bridge-helper.
The ACLs are fairly simple whitelist/blacklist mechanisms with a wildcard of
'all'. All users are blacklisted by default, and deny takes precedence over
allow.
An interesting feature of this ACL mechanism is that you can include external
ACL files. The main reason to support this is so that you can set different
file system permissions on those external ACL files. This allows an
administrator to implement rather sophisticated ACL policies based on
user/group policies via the file system.
As an example:
/etc/qemu/bridge.conf root:qemu 0640
allow br0
include /etc/qemu/alice.conf
include /etc/qemu/bob.conf
include /etc/qemu/charlie.conf
/etc/qemu/alice.conf root:alice 0640
allow br1
/etc/qemu/bob.conf root:bob 0640
allow br2
/etc/qemu/charlie.conf root:charlie 0640
deny all
This ACL pattern allows any user in the qemu group to get a tap device
connected to br0 (which is bridged to the physical network).
Users in the alice group can additionally get a tap device connected to br1.
This allows br1 to act as a private bridge for the alice group.
Users in the bob group can additionally get a tap device connected to br2.
This allows br2 to act as a private bridge for the bob group.
Users in the charlie group cannot get a tap device connected to any bridge.
Under no circumstance can the bob group get access to br1 or can the alice
group get access to br2. And under no cicumstance can the charlie group
get access to any bridge.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Richa Marwaha <rmarwah@linux.vnet.ibm.com>
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch adds a helper that can be used to create a tap device attached to
a bridge device. Since this helper is minimal in what it does, it can be
given CAP_NET_ADMIN which allows qemu to avoid running as root while still
satisfying the majority of what users tend to want to do with tap devices.
The way this all works is that qemu launches this helper passing a bridge
name and the name of an inherited file descriptor. The descriptor is one
end of a socketpair() of domain sockets. This domain socket is used to
transmit a file descriptor of the opened tap device from the helper to qemu.
The helper can then exit and let qemu use the tap device.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Richa Marwaha <rmarwah@linux.vnet.ibm.com>
Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Bugfix after reboot when vmmouse was enabled and another OS which uses e.g. PS/2
mouse.
Details:
When a guest activated the vmmouse followed by a reboot the vmmouse was still
enabled and the PS/2 mouse was therefore unsusable. When another guest is then
booted without vmmouse support (e.g. PS/2 mouse) the mouse is not working.
Reason is that VMMouse has priority and disables all other mouse entities
and therefore must be disabled on reset.
Testscenario:
1.) Boot e.g. OS with VMMouse support (e.g. Windows with VMMouse tools)
2.) reboot
3.) Boot e.g. OS without VMMouse support (e.g. DOS) => PS/2 mouse doesn't work
any more. Fixes that issue.
Testscenario 2 by Jan Kiszka <jan.kiszka@siemens.com>:
Confirm that this patch fixes a real issue. Setup: qemu.git,
opensuse 11.4 guest, SDL graphic, system_reset while guest is using the
vmmouse. Without the patch, the vmmouse become unusable after the
reboot. Also, the mouse stays in absolute mode even before X starts again.
Fixed by:
Disabling the vmmouse in its reset handler.
Tested-by: Andreas F=E4rber <afaerber@suse.de>
Signed-off-by: Gerhard Wiesinger <lists@wiesinger.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The lockf() call in qemu_create_pidfile() aims at ensuring mutual
exclusion. We shouldn't close the pidfile on success (as introduced by
commit 1bbd1592), because that drops the lock as well [1]:
"File locks shall be released on first close by the locking process
of any file descriptor for the file."
Coverity may complain again about the leaked file descriptor; let's
worry about that later.
v1->v2:
- add reference to 1bbd1592
- explain the intentional fd leak in the source
[1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/lockf.html
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In some cases initializing the alarm timers can lead to non-negligable
overhead from programs that link against qemu-tool.o. At least,
setting a max-resolution WinMM alarm timer via mm_start_timer() (the
current default for Windows) can increase the "tick rate" on Windows
OSs and affect frequency scaling, and in the case of tools that run
in guest OSs such has qemu-ga, the impact can be fairly dramatic
(+20%/20% user/sys time on a core 2 processor was observed from an idle
Windows XP guest).
This patch doesn't address the issue directly (not sure what a good
solution would be for Windows, or what other situations it might be
noticeable), but it at least limits the scope of the issue to programs
that "opt-in" to using the main-loop.c functions by only enabling alarm
timers when qemu_init_main_loop() is called, which is already required
to make use of those facilities, so existing users shouldn't be
affected.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The __attribute__((constructor)) init_main_loop() automatically get
called if qemu-tool.o is linked in. On win32, this leads to
a qemu_notify_event() call which attempts to SetEvent() on a HANDLE that
won't be initialized until qemu_init_main_loop() is manually called,
breaking qemu-tools.o programs on Windows at runtime.
This patch checks for an initialized event handle before attempting to
set it, which is analoguous to how we deal with an unitialized
io_thread_fd in the posix implementation.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The build process of optionroms spits out an "rm ..." line. Moreover, it
removes all .o files that can be handy for debugging purposes. So
disable automatic intermediate removal.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
There are scenarios on Linux with some SDL versions where
handle_activation is continuous invoked with state = SDL_APPINPUTFOCUS
and gain = 0 while we grabbed the input. This causes a ping-pong when we
grab the input after an absolute mouse entered the window.
As this sdl_grab_end was once introduced to work around a Windows-only
issue (0294ffb9c8), limit it to that platform.
CC: Erik Rull <erik.rull@rdsoftware.de>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
By grabbing the input already on button down, we leave the button in
that state for the host GUI. Thus it takes another click after releasing
the input again to synchronize the mouse button state.
Avoid this by grabbing on button up.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This reverts commit 6bb816031f.
SDL_WM_GrabInput does not reliably bail out if grabbing is impossible.
So if we get here, we already lost and will block. But this can no
longer happen due to the check in sdl_grab_start. So this patch became
obsolete.
Conflicts:
sdl.c
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Consistently check for SDL_APPINPUTFOCUS before trying to grab the input
focus. Just checking for SDL_APPACTIVE doesn't work. Moving the check to
sdl_grab_start allows for some consolidation.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
When the mouse mode changes to absolute while the SDL windows is not in
focus, refrain from grabbing the input. It would steal from some other
window.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
So far we overwrite the machine options completely with defaults if no
accel=value is provided. More user friendly is to fill in only
unspecified options. The new qemu_opts_set_defaults enables this.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Allow to configure the MC146818 RTC via the new lost tick policy
property and replace rtc_td_hack with this mechanism.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This adds qemu_opts_set_defaults, an interface provide default values
for a QemuOpts set. Default options are parsed from a string and then
prepended to the list of existing options, or they serve as the sole
QemuOpts set.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Potentially tick-generating timer devices will gain a common property:
lock_tick_policy. It allows to encode 4 different ways how to deal with
tick events the guest did not process in time:
discard - ignore lost ticks (e.g. if the guest compensates for them
already)
delay - replay all lost ticks in a row once the guest accepts them
again
merge - if multiple ticks are lost, all of them are merged into one
which is replayed once the guest accepts it again
slew - lost ticks are gradually replayed at a higher frequency than
the original tick
Not all timer device will need to support all modes. However, all need
to accept the configuration via this common property.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
configure creates a linux-headers/asm symlink. Remove this when
doing a distclean.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Clarify the comment about tlb_flush()'s flush_global parameter,
so it is clearer what it does and why it is OK that the implementation
currently ignores it.
Reviewed-by: Andreas F=C3=A4rber <afaerber@suse.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Up to now, there was no special section for the different
host operating systems used with QEMU.
scripts/get_maintainer.pl did not show a maintainer for
OS specific files and patches.
Therefore I added three hosts systems:
* POSIX for the majority of host systems which are supported.
This includes BSD and Linux host systems.
* LINUX is a special case of POSIX needed for some Linux specific
files and directories.
* W32, W64 for a well known family of closed source operating systems.
I also added myself as a maintainer for W32, W64.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Current './configure --static && make' fails for me:
LINK qemu-nbd
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lssl3
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lsmime3
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lnssutil3
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lnss3
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lplds4
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lplc4
/usr/lib/gcc/x86_64-pc-linux-gnu/4.5.3/../../../../x86_64-pc-linux-gnu/bin/ld: cannot find -lnspr4
My system does not provide static libraries for nss, so
fix autoconfiguration by link checking.
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
CC: qemu-trivial <qemu-trivial@nongnu.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Added wrapper around pkg-config to allow:
- safe options injection via ${QEMU_PKG_CONFIG_FLAGS}
- spaces in path to pkg-config
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
CC: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This lets the RTC get adjustments from the host NTP client.
The watchdog still uses the vm_clock. The previous behavior is
available with "-rtc clock=vm".
Cc: Andreas Färber <afaerber@suse.de>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This patch implements the RX channel of GRLIB UART with a FIFO to
improve data rate.
Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
* 'target-arm.for-upstream' of git://git.linaro.org/people/pmaydell/qemu-arm:
Add Cortex-A15 CPU definition
Add dummy implementation of generic timer cp15 registers
arm: store the config_base_register during cpu_reset
target-arm/helper.c: Don't assume softfloat int32 is 32 bits only
target-arm: Fix implementation of TLB invalidate operations
Commit 999e12bbe8 (sysbus: apic: ioapic:
convert to QEMU Object Model) introduced two typos, one of which broke
the mac99 machine.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This converts three devices because apic and ioapic are subclasses of sysbus.
Converting subclasses independently of their base class is prohibitively hard.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add -pcihost to SysBus devices to resolve name conflicts,
and clarify PCI vs. Internal PCI.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
This converts two types because smbus is implemented as a subclass of i2c. It's
extremely difficult to convert these two independently.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This converts two devices at once because PIC subclasses ISA and converting
subclasses independently is extremely hard.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
These are various small stylistic changes which help make things more
consistent such that the automated conversion script can be simpler.
It's not necessary to agree or disagree with these style changes because all
of this code is going to be rewritten by the patch monkey script anyway.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Since we are still dynamically creating TypeInfo, we need to chain the
class_init function in order to be able to make use of it within subclasses of
TYPE_DEVICE.
This will disappear once we register TypeInfos directly.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In order to introduce inheritance while still using the qdev registration
interfaces, we need to be able to use a parent other than TYPE_DEVICE. Add a
new interface that allows this.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Corey Bryant