qemu-patch-raspberry4/net/filter.c
Lukas Straub 1973136532 net/filter.c: Add Options to insert filters anywhere in the filter list
To switch the Secondary to Primary, we need to insert new filters
before the filter-rewriter.

Add the options insert= and position= to be able to insert filters
anywhere in the filter list.

position should be "head" or "tail" to insert at the head or
tail of the filter list or it should be "id=<id>" to specify
the id of another filter.
insert should be either "before" or "behind" to specify where to
insert the new filter relative to the one specified with position.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-03-03 18:04:47 +08:00

383 lines
11 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,
NULL);
object_property_add_enum(obj, "queue", "NetFilterDirection",
&NetFilterDirection_lookup,
netfilter_get_direction, netfilter_set_direction,
NULL);
object_property_add_str(obj, "status",
netfilter_get_status, netfilter_set_status,
NULL);
object_property_add_str(obj, "position",
netfilter_get_position, netfilter_set_position,
NULL);
object_property_add_str(obj, "insert",
netfilter_get_insert, netfilter_set_insert,
NULL);
}
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);