Commit Graph

314 Commits

Author SHA1 Message Date
Daniel P. Berrange
58eb4f2cbb Support loading a configuration file for sanlock plugin
Introduce a configuration file with a single parameter
'require_lease_for_disks', which is used to decide whether
it is allowed to start a guest which has read/write disks,
but without any leases.

* libvirt.spec.in: Add sanlock config file and augeas
  lens
* src/Makefile.am: Install sanlock config file and
  augeas lens
* src/locking/libvirt_sanlock.aug: Augeas master lens
* src/locking/test_libvirt_sanlock.aug: Augeas test file
* src/locking/sanlock.conf: Example sanlock config
* src/locking/lock_driver_sanlock.c: Wire up loading
  of configuration file
2011-06-28 18:07:06 +01:00
Daniel P. Berrange
5df29ebc25 Allow per-driver config file for lock manager plugins
Allow a 'configFile' parameter to be passed into the lock
drivers to provide configuration. Wire up the QEMU driver
to pass in file names '/etc/libvirt/qemu-$NAME.conf
eg qemu-sanlock.conf

* src/locking/lock_driver.h, src/locking/lock_driver_nop.c,
  src/locking/lock_driver_sanlock.c, src/locking/lock_manager.c,
  src/locking/lock_manager.h: Add configFile parameter
* src/qemu/qemu_conf.c: Pass in configuration file path to
  lock driver plugins
2011-06-28 18:07:06 +01:00
Daniel P. Berrange
5247b0695a Ensure sanlock socket is labelled with the VM process label
The libvirt sanlock plugin is intentionally leaking a file
descriptor to QEMU. To enable QEMU to use this FD under
SELinux, it must be labelled correctly. We dont want to use
the svirt_image_t for this, since QEMU must not be allowed
to actually use the FD. So instead we label it with svirt_t
using virSecurityManagerSetProcessFDLabel

* src/locking/domain_lock.c, src/locking/domain_lock.h,
  src/locking/lock_driver.h, src/locking/lock_driver_nop.c,
  src/locking/lock_driver_sanlock.c, src/locking/lock_manager.c,
  src/locking/lock_manager.h: Optionally pass an FD back to
  the hypervisor for security driver labelling
* src/qemu/qemu_process.c: label the lock manager plugin
  FD with the process label
2011-06-28 16:41:46 +01:00
Eric Blake
89d994ad6b build: update gnulib for intprops
Done as a separate commit to make backporting the next patch easier.
We are already using "intprops.h", but this makes it explicit.

* .gnulib: Update, for syntax-check fix.
* bootstrap.conf (gnulib_modules): Make intprops use explicit.
* src/locking/domain_lock.c (includes): Drop unused header.
* src/nwfilter/nwfilter_learnipaddr.c (includes): Use "", not <>,
for gnulib.
2011-06-24 15:52:52 -06:00
Daniel P. Berrange
cc743e2314 Add missing checks for NULL in domain lock manager
The domain lock manager forgot to include a bunch of checks
for NULL which could occur on OOM

* src/locking/domain_lock.c: Add checks for NULL
2011-06-17 11:02:23 +01:00
Matthias Bolte
6b5c589d84 Make dlopen usage in lock manager conditional
This fixes a build failure on MinGW, due to MinGW not supporting dlopen.
2011-06-03 16:46:09 +02:00
Eric Blake
0a41733c13 lock: avoid leak on failure
Detected by Coverity.  Only possible on OOM situations.

* src/locking/lock_manager.c (virLockManagerPluginNew): Plug leak.
2011-06-03 08:11:43 -06:00
Daniel P. Berrange
eb661ce3ee Avoid crash on NULL pointer in lock driver impls during hotplug
When virLockDriverAcquire is invoked during hotplug the state
parameter will be left as NULL.

* src/locking/lock_driver_nop.c,
  src/locking/lock_driver_sanlock.c: Don't reference NULL state
  parameter
2011-06-02 17:23:45 +01:00
Daniel P. Berrange
09240ef13b Fix return value in lock manager hotplug methods
Refactoring of the lock manager hotplug methods lost the
ret = 0 assignment for successful return path

* src/locking/domain_lock.c: Add missing ret = 0 assignments
2011-06-02 17:23:44 +01:00
Daniel P. Berrange
ebfb8c4243 Add call to sanlock_restrict() in QEMU lock driver
In between fork and exec, a connection to sanlock is acquired
and the socket file descriptor is intionally leaked to the
child process. sanlock watches this FD for POLL_HANGUP to
detect when QEMU has exited. We don't want a rogus/compromised
QEMU from issuing sanlock RPC calls on the leaked FD though,
since that could be used to DOS other guests. By calling
sanlock_restrict() on the socket before exec() we can lock
it down.

* configure.ac: Check for sanlock_restrict API
* src/locking/domain_lock.c: Restrict lock acquired in
  process startup phase
* src/locking/lock_driver.h: Add VIR_LOCK_MANAGER_ACQUIRE_RESTRICT
* src/locking/lock_driver_sanlock.c: Add call to sanlock_restrict
  when requested by VIR_LOCK_MANAGER_ACQUIRE_RESTRICT flag
2011-06-02 17:23:44 +01:00
Daniel P. Berrange
9f135031ff Add a plugin for the 'sanlock' project
Sanlock is a project that implements a disk-paxos locking
algorithm. This is suitable for cluster deployments with
shared storage.

* src/Makefile.am: Add dlopen plugin for sanlock
* src/locking/lock_driver_sanlock.c: Sanlock driver
* configure.ac: Check for sanlock
* libvirt.spec.in: Add a libvirt-lock-sanlock RPM
2011-06-02 10:54:01 +01:00
Daniel P. Berrange
ad73a937ff Add higher level lock API for domain objects
To facilitate use of the locking plugins from hypervisor drivers,
introduce a higher level API for locking virDomainObjPtr instances.
In includes APIs targetted to VM startup, and hotplug/unplug

* src/Makefile.am: Add domain lock API
* src/locking/domain_lock.c, src/locking/domain_lock.h: High
  level API for domain locking
2011-06-02 10:54:01 +01:00
Daniel P. Berrange
db98851c24 Add a 'nop' lock driver implementation.
To allow hypervisor drivers to assume that a lock driver impl
will be guaranteed to exist, provide a 'nop' impl that is
compiled into the library

* src/Makefile.am: Add nop driver
* src/locking/lock_driver_nop.c, src/locking/lock_driver_nop.h:
  Nop lock driver implementation
* src/locking/lock_manager.c: Enable direct access of 'nop'
  driver, instead of dlopen()ing it.
2011-06-02 10:54:00 +01:00
Daniel P. Berrange
6a943419c5 Basic framework for lock manager plugins
Define the basic framework lock manager plugins. The
basic plugin API for 3rd parties to implemented is
defined in

  src/locking/lock_driver.h

This allows dlopen()able modules for alternative locking
schemes, however, we do not install the header. This
requires lock plugins to be in-tree allowing changing of
the lock manager plugin API in future.

The libvirt code for loading & calling into plugins
is in

  src/locking/lock_manager.{c,h}

* include/libvirt/virterror.h, src/util/virterror.c: Add
  VIR_FROM_LOCKING
* src/locking/lock_driver.h: API for lock driver plugins
  to implement
* src/locking/lock_manager.c, src/locking/lock_manager.h:
  Internal API for managing locking
* src/Makefile.am: Add locking code
2011-06-02 10:54:00 +01:00