This patch adds support for L3/L4 filtering using iptables. This adds
support for 'tcp', 'udp', 'icmp', 'igmp', 'sctp' etc. filtering.

As mentioned in the introduction, a .c file provided by this patch
is #include'd into a .c file. This will need work, but should be alright
for review.
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch adds IPv6 support for the ebtables layer. Since the parser
etc. are all parameterized, it was fairly easy to add this...
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

Add support for Qemu to have firewall rules applied and removed on VM
startup and shutdown respectively. This  patch also provides support for
the updating of a filter that causes all VMs that reference the filter
to have their ebtables/iptables rules updated.
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch implements the core driver and provides
- management functionality for managing the filter XMLs
- compiling the internal filter representation into ebtables rules
- applying ebtables rules on a network (tap,macvtap) interface
- tearing down ebtables rules that were applied on behalf of an
interface
- updating of filters while VMs are running and causing the firewalls to
be rebuilt
- other bits and pieces
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch adds XML processing for the network filter schema
and extends the domain XML processing to parse the top level
referenced filter along with potentially provided parameters
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>
Signed-off-by: NGerhard Stenzel <gerhard.stenzel@de.ibm.com>

This patch adds the definition of the wire format for RPC calls
and implementation of the RPC client & server code
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch adds the implementation of the public API for the network
filtering (ACL) extensions to libvirt.c .
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch adds the internal API extensions for network filtering (ACL) support.
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

This patch adds recursive locks necessary due to the processing of
network filter XML that can reference other network filters, including
references that cause looks. Loops in the XML are prevented but their
detection requires recursive locks.
Signed-off-by: NStefan Berger <stefanb@us.ibm.com>

* Add types to switch; the switch is only exectuted for known types because of a preceding conditional, so this fix is merely to placate the compiler.

To find out where the net type 'direct' needs to be handled I introduced
the 'enum virDomainNetType' in the virDomainNetDef structure and let the
compiler tell me where the case statement is missing. Then I added the
unhandled device statement to the UML driver.

* src/conf/domain_conf.h: change _virDomainNetDef type from int to
  virDomainNetType enum
* src/conf/domain_conf.c src/lxc/lxc_driver.c src/qemu/qemu_conf.c
  src/uml/uml_conf.c: make sure all enum cases are properly handled
  in switches

Use the new virDomainUpdateDeviceFlags API to allow the VNC password
to be changed on the fly

* src/internal.h: Define STREQ_NULLABLE() which is like STREQ()
  but does not crash if either argument is NULL, and treats two
  NULLs as equal.
* src/libvirt_private.syms: Export virDomainGraphicsTypeToString
* src/qemu/qemu_driver.c: Support VNC password change on a live
  machine
* src/qemu/qemu_monitor.c: Disable crazy debugging info. Treat a
  NULL password as "" (empty string), allowing passwords to be
  disabled in the monitor

Expand the parser for the standalone <device> XML format to
allow inclusion of the <graphics> device type

* src/conf/domain_conf.h: Add virDomainGraphicsDef to
  the virDomainDeviceDef struct
* src/conf/domain_conf.c: Wire up parser for virDomainGraphicsDef
  to virDomainDeviceDefParse method

To allow the new virDomainUpdateDeviceFlags() API to be universally
used with all drivers, this patch adds an impl to all the current
drivers which support CDROM or Floppy disk media change via the
current virDomainAttachDeviceFlags API

* src/qemu/qemu_driver.c, src/vbox/vbox_tmpl.c,
  src/xen/proxy_internal.c, src/xen/xen_driver.c,
  src/xen/xend_internal.c: Implement media change via the
  virDomainUpdateDeviceFlags API
* src/xen/xen_driver.h, src/xen/xen_hypervisor.c,
  src/xen/xen_inotify.c, src/xen/xm_internal.c,
  src/xen/xs_internal.c: Stubs for Xen driver entry points

This defines the wire format for the new virDomainUpdateDeviceFlags()
API, and implements the server & client side of the marshalling code.

* daemon/remote.c: Server side dispatch for virDomainUpdateDeviceFlags
* src/remote/remote_driver.c: Client side serialization for
  virDomainUpdateDeviceFlags
* src/remote/remote_protocol.x: Define wire format for
  virDomainUpdateDeviceFlags
* daemon/remote_dispatch_args.h, daemon/remote_dispatch_prototypes.h,
  daemon/remote_dispatch_table.h, src/remote/remote_protocol.c,
  src/remote/remote_protocol.h: Re-generate code

The current virDomainAttachDevice API can be (ab)used to change
the media of an existing CDROM/Floppy device. Going forward there
will be more devices that can be configured on the fly and overloading
virDomainAttachDevice for this is not too pleasant. This patch adds
a new virDomainUpdateDeviceFlags() explicitly just for modifying
existing devices.

* include/libvirt/libvirt.h.in: Add virDomainUpdateDeviceFlags
* src/driver.h: Internal API for virDomainUpdateDeviceFlags
* src/libvirt.c, src/libvirt_public.syms: Glue public API to
  driver API
* src/esx/esx_driver.c, src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
  src/openvz/openvz_driver.c, src/phyp/phyp_driver.c, src/qemu/qemu_driver.c,
  src/remote/remote_driver.c, src/test/test_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c, src/xenapi/xenapi_driver.c: Add
  stubs for new driver entry point

This introduces a new event type

   VIR_DOMAIN_EVENT_ID_GRAPHICS

The same event can be emitted in 3 scenarios

  typedef enum {
      VIR_DOMAIN_EVENT_GRAPHICS_CONNECT = 0,
      VIR_DOMAIN_EVENT_GRAPHICS_INITIALIZE,
      VIR_DOMAIN_EVENT_GRAPHICS_DISCONNECT,
  } virDomainEventGraphicsPhase;

Connect/disconnect are triggered at socket accept/close.
The initialize phase is immediately after the protocol
setup and authentication has completed. ie when the
client is authorized and about to start interacting with
the graphical desktop

This event comes with *a lot* of potential information

 - IP address, port & address family of client
 - IP address, port & address family of server
 - Authentication scheme (arbitrary string)
 - Authenticated subject identity. A subject may have
   multiple identities with some authentication schemes.
   For example, vencrypt+sasl results in a x509dname
   and saslUsername identities.

This results in a very complicated callback :-(

   typedef enum {
      VIR_DOMAIN_EVENT_GRAPHICS_ADDRESS_IPV4,
      VIR_DOMAIN_EVENT_GRAPHICS_ADDRESS_IPV6,
   } virDomainEventGraphicsAddressType;

   struct _virDomainEventGraphicsAddress {
       int family;
       const char *node;
       const char *service;
   };
   typedef struct _virDomainEventGraphicsAddress virDomainEventGraphicsAddress;
   typedef virDomainEventGraphicsAddress *virDomainEventGraphicsAddressPtr;

   struct _virDomainEventGraphicsSubject {
      int nidentity;
      struct {
          const char *type;
          const char *name;
      } *identities;
   };
   typedef struct _virDomainEventGraphicsSubject virDomainEventGraphicsSubject;
   typedef virDomainEventGraphicsSubject *virDomainEventGraphicsSubjectPtr;

   typedef void (*virConnectDomainEventGraphicsCallback)(virConnectPtr conn,
                                                         virDomainPtr dom,
                                                         int phase,
                                                         virDomainEventGraphicsAddressPtr local,
                                                         virDomainEventGraphicsAddressPtr remote,
                                                         const char *authScheme,
                                                         virDomainEventGraphicsSubjectPtr subject,
                                                         void *opaque);

The wire protocol is similarly complex

   struct remote_domain_event_graphics_address {
     int family;
     remote_nonnull_string node;
     remote_nonnull_string service;
   };

   const REMOTE_DOMAIN_EVENT_GRAPHICS_IDENTITY_MAX = 20;

   struct remote_domain_event_graphics_identity {
     remote_nonnull_string type;
     remote_nonnull_string name;
   };

   struct remote_domain_event_graphics_msg {
     remote_nonnull_domain dom;
     int phase;
     remote_domain_event_graphics_address local;
     remote_domain_event_graphics_address remote;
     remote_nonnull_string authScheme;
     remote_domain_event_graphics_identity subject<REMOTE_DOMAIN_EVENT_GRAPHICS_IDENTITY_MAX>;
   };

This is currently implemented in QEMU for the VNC graphics
protocol, but designed to be usable with SPICE graphics in
the future too.

* daemon/remote.c: Dispatch graphics events to client
* examples/domain-events/events-c/event-test.c: Watch for
  graphics events
* include/libvirt/libvirt.h.in: Define new graphics event ID
  and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Extend API to handle graphics events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
  for VNC events and emit a libvirt graphics event
* src/remote/remote_driver.c: Receive and dispatch graphics
  events to application
* src/remote/remote_protocol.x: Wire protocol definition for
  graphics events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c: Watch for VNC_CONNECTED,
  VNC_INITIALIZED & VNC_DISCONNETED events from QEMU monitor

This introduces a new event type

   VIR_DOMAIN_EVENT_ID_IO_ERROR

This event includes the action that is about to be taken
as a result of the watchdog triggering

  typedef enum {
     VIR_DOMAIN_EVENT_IO_ERROR_NONE = 0,
     VIR_DOMAIN_EVENT_IO_ERROR_PAUSE,
     VIR_DOMAIN_EVENT_IO_ERROR_REPORT,
  } virDomainEventIOErrorAction;

In addition it has the source path of the disk that had the
error and its unique device alias. It does not include the
target device name (/dev/sda), since this would preclude
triggering IO errors from other file backed devices (eg
serial ports connected to a file)

Thus there is a new callback definition for this event type

typedef void (*virConnectDomainEventIOErrorCallback)(virConnectPtr conn,
                                                     virDomainPtr dom,
                                                     const char *srcPath,
                                                     const char *devAlias,
                                                     int action,
                                                     void *opaque);

This is currently wired up to the QEMU block IO error events

* daemon/remote.c: Dispatch IO error events to client
* examples/domain-events/events-c/event-test.c: Watch for
  IO error events
* include/libvirt/libvirt.h.in: Define new IO error event ID
  and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Extend API to handle IO error events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
  for block IO errors and emit a libvirt IO error event
* src/remote/remote_driver.c: Receive and dispatch IO error
  events to application
* src/remote/remote_protocol.x: Wire protocol definition for
  IO error events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c: Watch for BLOCK_IO_ERROR event
  from QEMU monitor

This introduces a new event type

   VIR_DOMAIN_EVENT_ID_WATCHDOG

This event includes the action that is about to be taken
as a result of the watchdog triggering

 typedef enum {
     VIR_DOMAIN_EVENT_WATCHDOG_NONE = 0,
     VIR_DOMAIN_EVENT_WATCHDOG_PAUSE,
     VIR_DOMAIN_EVENT_WATCHDOG_RESET,
     VIR_DOMAIN_EVENT_WATCHDOG_POWEROFF,
     VIR_DOMAIN_EVENT_WATCHDOG_SHUTDOWN,
     VIR_DOMAIN_EVENT_WATCHDOG_DEBUG,
 } virDomainEventWatchdogAction;

Thus there is a new callback definition for this event type

 typedef void (*virConnectDomainEventWatchdogCallback)(virConnectPtr conn,
                                                       virDomainPtr dom,
                                                       int action,
                                                       void *opaque);

* daemon/remote.c: Dispatch watchdog events to client
* examples/domain-events/events-c/event-test.c: Watch for
  watchdog events
* include/libvirt/libvirt.h.in: Define new watchdg event ID
  and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Extend API to handle watchdog events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
  for watchdogs and emit a libvirt watchdog event
* src/remote/remote_driver.c: Receive and dispatch watchdog
  events to application
* src/remote/remote_protocol.x: Wire protocol definition for
  watchdog events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c: Watch for WATCHDOG event
  from QEMU monitor

This introduces a new event type

   VIR_DOMAIN_EVENT_ID_RTC_CHANGE

This event includes the new UTC offset measured in seconds.
Thus there is a new callback definition for this event type

 typedef void (*virConnectDomainEventRTCChangeCallback)(virConnectPtr conn,
                                                        virDomainPtr dom,
                                                        long long utcoffset,
                                                        void *opaque);

If the guest XML configuration for the <clock> is set to
offset='variable', then the XML will automatically be
updated with the new UTC offset value. This ensures that
during migration/save/restore the new offset is preserved.

* daemon/remote.c: Dispatch RTC change events to client
* examples/domain-events/events-c/event-test.c: Watch for
  RTC change events
* include/libvirt/libvirt.h.in: Define new RTC change event ID
  and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Extend API to handle RTC change events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
  for RTC changes and emit a libvirt RTC change event
* src/remote/remote_driver.c: Receive and dispatch RTC change
  events to application
* src/remote/remote_protocol.x: Wire protocol definition for
  RTC change events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c: Watch for RTC_CHANGE event
  from QEMU monitor

The reboot event is not a normal lifecycle event, since the
virtual machine on the host does not change state. Rather the
guest OS is resetting the virtual CPUs. ie, the QEMU process
does not restart. Thus, this does not belong in the current
lifecycle events callback.

This introduces a new event type

    VIR_DOMAIN_EVENT_ID_REBOOT

It takes no parameters, besides the virDomainPtr, so it can
use the generic callback signature.

* daemon/remote.c: Dispatch reboot events to client
* examples/domain-events/events-c/event-test.c: Watch for
  reboot events
* include/libvirt/libvirt.h.in: Define new reboot event ID
* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Extend API to handle reboot events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
  for reboots and emit a libvirt reboot event
* src/remote/remote_driver.c: Receive and dispatch reboot
  events to application
* src/remote/remote_protocol.x: Wire protocol definition for
  reboot events

To avoid confusion, rename the current REMOTE_PROC_DOMAIN_EVENT
message to REMOTE_PROC_DOMAIN_EVENT_LIFECYCLE. This does not
cause ABI problems, since the names are only relevant at the source
code level. On the wire they encoding is a plain integer whose
value does not change

* src/remote/remote_protocol.x: Rename REMOTE_PROC_DOMAIN_EVENT
  to REMOTE_PROC_DOMAIN_EVENT_LIFECYCLE.
* daemon/remote.c, src/remote/remote_driver.c: Update code for
  renamed event

This wires up the remote driver to handle the new events APIs.
The public API allows an application to request a callback filters
events to a specific domain object, and register multiple callbacks
for the same event type. On the wire there are two strategies for
this

 - Register multiple callbacks with the remote daemon, each
   with filtering as needed
 - Register only one callback per event type, with no filtering

Both approaches have potential inefficiency. In the first scheme,
the same event gets sent over the wire many times if multiple
callbacks are registered. With the second scheme, unneccessary
events get sent over the wire if a per-domain filter is set on
the client. The second scheme is far easier to implement though,
so this patch takes that approach.

* daemon/dispatch.h: Don't export remoteRelayDomainEvent since it
  is no longer needed for unregistering callbacks, instead the
  unique callback ID is used
* daemon/libvirtd.c, daemon/libvirtd.h: Track and unregister
  callbacks based on callback ID, instead of function pointer
* daemon/remote.c: Switch over to using virConnectDomainEventRegisterAny
  instead of legacy virConnectDomainEventRegister function. Refactor
  remoteDispatchDomainEventSend() to cope with arbitrary event types
* src/driver.h, src/driver.c: Move verify() call into source file
  instead of header, to avoid polluting the global namespace with
  the verify function name
* src/remote/remote_driver.c: Implement new APIs for event
  registration. Refactor processCallDispatchMessage() to cope
  with arbitrary incoming event types. Merge remoteDomainQueueEvent()
  into processCallDispatchMessage() to avoid duplication of code.
  Rename remoteDomainReadEvent() to remoteDomainReadEventLifecycle()
* src/remote/remote_protocol.x: Define wire format for the new
  virConnectDomainEventRegisterAny and virConnectDomainEventDeregisterAny
  functions

The libvirtd daemon impl will need to switch over to using the
new event APIs. To make this simpler, ensure all drivers currently
providing events support both the new APIs and old APIs.

* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c, src/test/test_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Implement the new
  virConnectDomainEvent(Dereg|Reg)isterAny driver entry points

The current internal domain events API tracks callbacks based on
the function pointer, and only supports lifecycle events. This
adds new internal APIs for registering callbacks for other event
types. These new APIs are postfixed with the word 'ID' to indicate
that they operated based on event ID, instead of hardcoded to
lifecycle events

* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Add new APIs for handling callbacks
  for non-lifecycle events

The internal domain events APIs are designed to handle the lifecycle
events. This needs to be refactored to allow arbitrary new event
types to be handled.

 * The signature of virDomainEventDispatchFunc changes to use
   virConnectDomainEventGenericCallback instead of the lifecycle
   event specific virConnectDomainEventCallback
 * Every registered callback gains a unique ID to allow its
   removal based on ID, instead of function pointer
 * Every registered callback gains an 'eventID' to allow callbacks
   for different types of events to be distinguished
 * virDomainEventDispatch is adapted to filter out callbacks
   whose eventID does not match the eventID of the event being
   dispatched
 * virDomainEventDispatch is adapted to filter based on the
   domain name and uuid, if this filter is set for a callback.
 * virDomainEvent type/detail fields are moved into a union to
   allow different data fields for other types of events to be
   added later

* src/conf/domain_event.h, src/conf/domain_event.c: Refactor
  to allow handling of different types of events
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
  src/remote/remote_driver.c, src/test/test_driver.c,
  src/xen/xen_driver.c: Change dispatch function signature
  to use virConnectDomainEventGenericCallback

The virtual box driver was directly accesing the domain events
structs instead of using the APIs provided. To prevent this kind
of abuse, make the struct definitions private, forcing use of the
internal APIs. This requires adding one extra internal API.

* src/conf/domain_event.h, src/conf/domain_event.c: Move
  virDomainEventCallback and virDomainEvent structs into
  the source file instead of header
* src/vbox/vbox_tmpl.c: Use official APIs for dispatching domain
  events instead of accessing structs directly.

The current API for domain events has a number of problems

 - Only allows for domain lifecycle change events
 - Does not allow the same callback to be registered multiple times
 - Does not allow filtering of events to a specific domain

This introduces a new more general purpose domain events API

  typedef enum {
     VIR_DOMAIN_EVENT_ID_LIFECYCLE = 0,       /* virConnectDomainEventCallback */
      ...more events later..
  }

  int virConnectDomainEventRegisterAny(virConnectPtr conn,
                                       virDomainPtr dom, /* Optional, to filter */
                                       int eventID,
                                       virConnectDomainEventGenericCallback cb,
                                       void *opaque,
                                       virFreeCallback freecb);

  int virConnectDomainEventDeregisterAny(virConnectPtr conn,
                                         int callbackID);

Since different event types can received different data in the callback,
the API is defined with a generic callback. Specific events will each
have a custom signature for their callback. Thus when registering an
event it is neccessary to cast the callback to the generic signature

eg

  int myDomainEventCallback(virConnectPtr conn,
                            virDomainPtr dom,
                            int event,
                            int detail,
                            void *opaque)
  {
    ...
  }

  virConnectDomainEventRegisterAny(conn, NULL,
                                   VIR_DOMAIN_EVENT_ID_LIFECYCLE,
                                   VIR_DOMAIN_EVENT_CALLBACK(myDomainEventCallback)
                                   NULL, NULL);

The VIR_DOMAIN_EVENT_CALLBACK() macro simply does a "bad" cast
to the generic signature

* include/libvirt/libvirt.h.in: Define new APIs for registering
  domain events
* src/driver.h: Internal driver entry points for new events APIs
* src/libvirt.c: Wire up public API to driver API for events APIs
* src/libvirt_public.syms: Export new APIs
* src/esx/esx_driver.c, src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
  src/openvz/openvz_driver.c, src/phyp/phyp_driver.c,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/test/test_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c,
  src/xenapi/xenapi_driver.c: Stub out new API entries

* cfg.mk (useless_free_options): Add virDomainDefFree to the list
of free-like functions.
* src/test/test_driver.c (testDomainCreateXML): Remove useless-if-
before-virDomainDefFree.
* src/conf/domain_conf.c (virDomainAssignDef): Likewise

The keys of entries in a VMX file are case insensitive. Both scsi0:1.fileName
and scsi0:1.filename are valid. Therefore, make the conf parser compare names
case insensitive in VMX mode to accept every capitalization variation.

Also add test cases for this.

<source file=''/> results in def->disks[i]->src == NULL. But
vboxDomainDefineXML and vboxDomainAttachDevice didn't check
def->disks[i]->src for NULL and expected it to be a valid string.

Add checks for def->disks[i]->src != NULL to fix the segfault.

* src/Makefile.am (augeas-check): New target, just to give the existing
rule a name.  At the same time, prefix the commands with $(AM_V_GEN),
to avoid unexpected build output with V=0 which is the default.

Before, this function would blindly accept an invalid def->dst
and then abuse the idx=-1 it would get from virDiskNameToIndex,
when passing it invalid strings like "xvda:disk" and "sda1".
Now, this function returns -1 upon failure.
* src/conf/domain_conf.c (virDomainDiskDefAssignAddress): as above.
Update callers.
* src/conf/domain_conf.h: Update prototype.
* src/qemu/qemu_conf.c: Update callers.

* src/util/util.c (virDiskNameToIndex): Accept sda1, and map it to "sda".
I.e., accept and ignore any string of trailing digits.

virSetCloseExec and virExecDaemonize were missing a body on Windows.