qemu/net/filter.c

378 lines
10 KiB
C

/*
* Copyright (c) 2015 FUJITSU LIMITED
* Author: Yang Hongyang <yanghy@cn.fujitsu.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/error-report.h"
#include "net/filter.h"
#include "net/net.h"
#include "net/vhost_net.h"
#include "qom/object_interfaces.h"
#include "qemu/iov.h"
#include "qemu/module.h"
#include "net/colo.h"
#include "migration/colo.h"
static inline bool qemu_can_skip_netfilter(NetFilterState *nf)
{
return !nf->on;
}
ssize_t qemu_netfilter_receive(NetFilterState *nf,
NetFilterDirection direction,
NetClientState *sender,
unsigned flags,
const struct iovec *iov,
int iovcnt,
NetPacketSent *sent_cb)
{
if (qemu_can_skip_netfilter(nf)) {
return 0;
}
if (nf->direction == direction ||
nf->direction == NET_FILTER_DIRECTION_ALL) {
return NETFILTER_GET_CLASS(OBJECT(nf))->receive_iov(
nf, sender, flags, iov, iovcnt, sent_cb);
}
return 0;
}
static NetFilterState *netfilter_next(NetFilterState *nf,
NetFilterDirection dir)
{
NetFilterState *next;
if (dir == NET_FILTER_DIRECTION_TX) {
/* forward walk through filters */
next = QTAILQ_NEXT(nf, next);
} else {
/* reverse order */
next = QTAILQ_PREV(nf, next);
}
return next;
}
ssize_t qemu_netfilter_pass_to_next(NetClientState *sender,
unsigned flags,
const struct iovec *iov,
int iovcnt,
void *opaque)
{
int ret = 0;
int direction;
NetFilterState *nf = opaque;
NetFilterState *next = NULL;
if (!sender || !sender->peer) {
/* no receiver, or sender been deleted, no need to pass it further */
goto out;
}
if (nf->direction == NET_FILTER_DIRECTION_ALL) {
if (sender == nf->netdev) {
/* This packet is sent by netdev itself */
direction = NET_FILTER_DIRECTION_TX;
} else {
direction = NET_FILTER_DIRECTION_RX;
}
} else {
direction = nf->direction;
}
next = netfilter_next(nf, direction);
while (next) {
/*
* if qemu_netfilter_pass_to_next been called, means that
* the packet has been hold by filter and has already retured size
* to the sender, so sent_cb shouldn't be called later, just
* pass NULL to next.
*/
ret = qemu_netfilter_receive(next, direction, sender, flags, iov,
iovcnt, NULL);
if (ret) {
return ret;
}
next = netfilter_next(next, direction);
}
/*
* We have gone through all filters, pass it to receiver.
* Do the valid check again incase sender or receiver been
* deleted while we go through filters.
*/
if (sender && sender->peer) {
qemu_net_queue_send_iov(sender->peer->incoming_queue,
sender, flags, iov, iovcnt, NULL);
}
out:
/* no receiver, or sender been deleted */
return iov_size(iov, iovcnt);
}
static char *netfilter_get_netdev_id(Object *obj, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
return g_strdup(nf->netdev_id);
}
static void netfilter_set_netdev_id(Object *obj, const char *str, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
nf->netdev_id = g_strdup(str);
}
static int netfilter_get_direction(Object *obj, Error **errp G_GNUC_UNUSED)
{
NetFilterState *nf = NETFILTER(obj);
return nf->direction;
}
static void netfilter_set_direction(Object *obj, int direction, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
nf->direction = direction;
}
static char *netfilter_get_status(Object *obj, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
return nf->on ? g_strdup("on") : g_strdup("off");
}
static void netfilter_set_status(Object *obj, const char *str, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
NetFilterClass *nfc = NETFILTER_GET_CLASS(obj);
if (strcmp(str, "on") && strcmp(str, "off")) {
error_setg(errp, "Invalid value for netfilter status, "
"should be 'on' or 'off'");
return;
}
if (nf->on == !strcmp(str, "on")) {
return;
}
nf->on = !nf->on;
if (nf->netdev && nfc->status_changed) {
nfc->status_changed(nf, errp);
}
}
static char *netfilter_get_position(Object *obj, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
return g_strdup(nf->position);
}
static void netfilter_set_position(Object *obj, const char *str, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
nf->position = g_strdup(str);
}
static char *netfilter_get_insert(Object *obj, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
return nf->insert_before_flag ? g_strdup("before") : g_strdup("behind");
}
static void netfilter_set_insert(Object *obj, const char *str, Error **errp)
{
NetFilterState *nf = NETFILTER(obj);
if (strcmp(str, "before") && strcmp(str, "behind")) {
error_setg(errp, "Invalid value for netfilter insert, "
"should be 'before' or 'behind'");
return;
}
nf->insert_before_flag = !strcmp(str, "before");
}
static void netfilter_init(Object *obj)
{
NetFilterState *nf = NETFILTER(obj);
nf->on = true;
nf->insert_before_flag = false;
nf->position = g_strdup("tail");
object_property_add_str(obj, "netdev",
netfilter_get_netdev_id, netfilter_set_netdev_id);
object_property_add_enum(obj, "queue", "NetFilterDirection",
&NetFilterDirection_lookup,
netfilter_get_direction, netfilter_set_direction);
object_property_add_str(obj, "status",
netfilter_get_status, netfilter_set_status);
object_property_add_str(obj, "position",
netfilter_get_position, netfilter_set_position);
object_property_add_str(obj, "insert",
netfilter_get_insert, netfilter_set_insert);
}
static void netfilter_complete(UserCreatable *uc, Error **errp)
{
NetFilterState *nf = NETFILTER(uc);
NetFilterState *position = NULL;
NetClientState *ncs[MAX_QUEUE_NUM];
NetFilterClass *nfc = NETFILTER_GET_CLASS(uc);
int queues;
Error *local_err = NULL;
if (!nf->netdev_id) {
error_setg(errp, "Parameter 'netdev' is required");
return;
}
queues = qemu_find_net_clients_except(nf->netdev_id, ncs,
NET_CLIENT_DRIVER_NIC,
MAX_QUEUE_NUM);
if (queues < 1) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "netdev",
"a network backend id");
return;
} else if (queues > 1) {
error_setg(errp, "multiqueue is not supported");
return;
}
if (get_vhost_net(ncs[0])) {
error_setg(errp, "Vhost is not supported");
return;
}
if (strcmp(nf->position, "head") && strcmp(nf->position, "tail")) {
Object *container;
Object *obj;
char *position_id;
if (!g_str_has_prefix(nf->position, "id=")) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "position",
"'head', 'tail' or 'id=<id>'");
return;
}
/* get the id from the string */
position_id = g_strndup(nf->position + 3, strlen(nf->position) - 3);
/* Search for the position to insert before/behind */
container = object_get_objects_root();
obj = object_resolve_path_component(container, position_id);
if (!obj) {
error_setg(errp, "filter '%s' not found", position_id);
g_free(position_id);
return;
}
position = NETFILTER(obj);
if (position->netdev != ncs[0]) {
error_setg(errp, "filter '%s' belongs to a different netdev",
position_id);
g_free(position_id);
return;
}
g_free(position_id);
}
nf->netdev = ncs[0];
if (nfc->setup) {
nfc->setup(nf, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
if (position) {
if (nf->insert_before_flag) {
QTAILQ_INSERT_BEFORE(position, nf, next);
} else {
QTAILQ_INSERT_AFTER(&nf->netdev->filters, position, nf, next);
}
} else if (!strcmp(nf->position, "head")) {
QTAILQ_INSERT_HEAD(&nf->netdev->filters, nf, next);
} else if (!strcmp(nf->position, "tail")) {
QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
}
}
static void netfilter_finalize(Object *obj)
{
NetFilterState *nf = NETFILTER(obj);
NetFilterClass *nfc = NETFILTER_GET_CLASS(obj);
if (nfc->cleanup) {
nfc->cleanup(nf);
}
if (nf->netdev && !QTAILQ_EMPTY(&nf->netdev->filters) &&
QTAILQ_IN_USE(nf, next)) {
QTAILQ_REMOVE(&nf->netdev->filters, nf, next);
}
g_free(nf->netdev_id);
g_free(nf->position);
}
static void default_handle_event(NetFilterState *nf, int event, Error **errp)
{
switch (event) {
case COLO_EVENT_CHECKPOINT:
break;
case COLO_EVENT_FAILOVER:
object_property_set_str(OBJECT(nf), "off", "status", errp);
break;
default:
break;
}
}
static void netfilter_class_init(ObjectClass *oc, void *data)
{
UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
NetFilterClass *nfc = NETFILTER_CLASS(oc);
ucc->complete = netfilter_complete;
nfc->handle_event = default_handle_event;
}
static const TypeInfo netfilter_info = {
.name = TYPE_NETFILTER,
.parent = TYPE_OBJECT,
.abstract = true,
.class_size = sizeof(NetFilterClass),
.class_init = netfilter_class_init,
.instance_size = sizeof(NetFilterState),
.instance_init = netfilter_init,
.instance_finalize = netfilter_finalize,
.interfaces = (InterfaceInfo[]) {
{ TYPE_USER_CREATABLE },
{ }
}
};
static void register_types(void)
{
type_register_static(&netfilter_info);
}
type_init(register_types);