linux/net/bridge/br_mdb.c
Linus Lüssing ff391c5d98 net: bridge: mcast: prepare mdb netlink for mcast router split
In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants and to avoid IPv6 #ifdef clutter later add
some inline functions for the protocol specific parts in the mdb router
netlink code. Also the we need iterate over the port instead of router
list to be able put one router port entry with both the IPv4 and IPv6
multicast router info later.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-13 14:04:31 -07:00

1282 lines
31 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/err.h>
#include <linux/igmp.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rculist.h>
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <net/ip.h>
#include <net/netlink.h>
#include <net/switchdev.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/addrconf.h>
#endif
#include "br_private.h"
static bool br_rports_have_mc_router(struct net_bridge *br)
{
return !hlist_empty(&br->ip4_mc_router_list);
}
static bool
br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
{
*timer = br_timer_value(&port->ip4_mc_router_timer);
return !hlist_unhashed(&port->ip4_rlist);
}
static bool
br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
{
*timer = 0;
return false;
}
static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
bool have_ip4_mc_rtr, have_ip6_mc_rtr;
unsigned long ip4_timer, ip6_timer;
struct nlattr *nest, *port_nest;
struct net_bridge_port *p;
if (!br->multicast_router)
return 0;
if (!br_rports_have_mc_router(br))
return 0;
nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
if (nest == NULL)
return -EMSGSIZE;
list_for_each_entry_rcu(p, &br->port_list, list) {
have_ip4_mc_rtr = br_ip4_rports_get_timer(p, &ip4_timer);
have_ip6_mc_rtr = br_ip6_rports_get_timer(p, &ip6_timer);
if (!have_ip4_mc_rtr && !have_ip6_mc_rtr)
continue;
port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
if (!port_nest)
goto fail;
if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
max(ip4_timer, ip6_timer)) ||
nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
p->multicast_router)) {
nla_nest_cancel(skb, port_nest);
goto fail;
}
nla_nest_end(skb, port_nest);
}
nla_nest_end(skb, nest);
return 0;
fail:
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
static void __mdb_entry_fill_flags(struct br_mdb_entry *e, unsigned char flags)
{
e->state = flags & MDB_PG_FLAGS_PERMANENT;
e->flags = 0;
if (flags & MDB_PG_FLAGS_OFFLOAD)
e->flags |= MDB_FLAGS_OFFLOAD;
if (flags & MDB_PG_FLAGS_FAST_LEAVE)
e->flags |= MDB_FLAGS_FAST_LEAVE;
if (flags & MDB_PG_FLAGS_STAR_EXCL)
e->flags |= MDB_FLAGS_STAR_EXCL;
if (flags & MDB_PG_FLAGS_BLOCKED)
e->flags |= MDB_FLAGS_BLOCKED;
}
static void __mdb_entry_to_br_ip(struct br_mdb_entry *entry, struct br_ip *ip,
struct nlattr **mdb_attrs)
{
memset(ip, 0, sizeof(struct br_ip));
ip->vid = entry->vid;
ip->proto = entry->addr.proto;
switch (ip->proto) {
case htons(ETH_P_IP):
ip->dst.ip4 = entry->addr.u.ip4;
if (mdb_attrs && mdb_attrs[MDBE_ATTR_SOURCE])
ip->src.ip4 = nla_get_in_addr(mdb_attrs[MDBE_ATTR_SOURCE]);
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
ip->dst.ip6 = entry->addr.u.ip6;
if (mdb_attrs && mdb_attrs[MDBE_ATTR_SOURCE])
ip->src.ip6 = nla_get_in6_addr(mdb_attrs[MDBE_ATTR_SOURCE]);
break;
#endif
default:
ether_addr_copy(ip->dst.mac_addr, entry->addr.u.mac_addr);
}
}
static int __mdb_fill_srcs(struct sk_buff *skb,
struct net_bridge_port_group *p)
{
struct net_bridge_group_src *ent;
struct nlattr *nest, *nest_ent;
if (hlist_empty(&p->src_list))
return 0;
nest = nla_nest_start(skb, MDBA_MDB_EATTR_SRC_LIST);
if (!nest)
return -EMSGSIZE;
hlist_for_each_entry_rcu(ent, &p->src_list, node,
lockdep_is_held(&p->key.port->br->multicast_lock)) {
nest_ent = nla_nest_start(skb, MDBA_MDB_SRCLIST_ENTRY);
if (!nest_ent)
goto out_cancel_err;
switch (ent->addr.proto) {
case htons(ETH_P_IP):
if (nla_put_in_addr(skb, MDBA_MDB_SRCATTR_ADDRESS,
ent->addr.src.ip4)) {
nla_nest_cancel(skb, nest_ent);
goto out_cancel_err;
}
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
if (nla_put_in6_addr(skb, MDBA_MDB_SRCATTR_ADDRESS,
&ent->addr.src.ip6)) {
nla_nest_cancel(skb, nest_ent);
goto out_cancel_err;
}
break;
#endif
default:
nla_nest_cancel(skb, nest_ent);
continue;
}
if (nla_put_u32(skb, MDBA_MDB_SRCATTR_TIMER,
br_timer_value(&ent->timer))) {
nla_nest_cancel(skb, nest_ent);
goto out_cancel_err;
}
nla_nest_end(skb, nest_ent);
}
nla_nest_end(skb, nest);
return 0;
out_cancel_err:
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
static int __mdb_fill_info(struct sk_buff *skb,
struct net_bridge_mdb_entry *mp,
struct net_bridge_port_group *p)
{
bool dump_srcs_mode = false;
struct timer_list *mtimer;
struct nlattr *nest_ent;
struct br_mdb_entry e;
u8 flags = 0;
int ifindex;
memset(&e, 0, sizeof(e));
if (p) {
ifindex = p->key.port->dev->ifindex;
mtimer = &p->timer;
flags = p->flags;
} else {
ifindex = mp->br->dev->ifindex;
mtimer = &mp->timer;
}
__mdb_entry_fill_flags(&e, flags);
e.ifindex = ifindex;
e.vid = mp->addr.vid;
if (mp->addr.proto == htons(ETH_P_IP))
e.addr.u.ip4 = mp->addr.dst.ip4;
#if IS_ENABLED(CONFIG_IPV6)
else if (mp->addr.proto == htons(ETH_P_IPV6))
e.addr.u.ip6 = mp->addr.dst.ip6;
#endif
else
ether_addr_copy(e.addr.u.mac_addr, mp->addr.dst.mac_addr);
e.addr.proto = mp->addr.proto;
nest_ent = nla_nest_start_noflag(skb,
MDBA_MDB_ENTRY_INFO);
if (!nest_ent)
return -EMSGSIZE;
if (nla_put_nohdr(skb, sizeof(e), &e) ||
nla_put_u32(skb,
MDBA_MDB_EATTR_TIMER,
br_timer_value(mtimer)))
goto nest_err;
switch (mp->addr.proto) {
case htons(ETH_P_IP):
dump_srcs_mode = !!(mp->br->multicast_igmp_version == 3);
if (mp->addr.src.ip4) {
if (nla_put_in_addr(skb, MDBA_MDB_EATTR_SOURCE,
mp->addr.src.ip4))
goto nest_err;
break;
}
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
dump_srcs_mode = !!(mp->br->multicast_mld_version == 2);
if (!ipv6_addr_any(&mp->addr.src.ip6)) {
if (nla_put_in6_addr(skb, MDBA_MDB_EATTR_SOURCE,
&mp->addr.src.ip6))
goto nest_err;
break;
}
break;
#endif
default:
ether_addr_copy(e.addr.u.mac_addr, mp->addr.dst.mac_addr);
}
if (p) {
if (nla_put_u8(skb, MDBA_MDB_EATTR_RTPROT, p->rt_protocol))
goto nest_err;
if (dump_srcs_mode &&
(__mdb_fill_srcs(skb, p) ||
nla_put_u8(skb, MDBA_MDB_EATTR_GROUP_MODE,
p->filter_mode)))
goto nest_err;
}
nla_nest_end(skb, nest_ent);
return 0;
nest_err:
nla_nest_cancel(skb, nest_ent);
return -EMSGSIZE;
}
static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev)
{
int idx = 0, s_idx = cb->args[1], err = 0, pidx = 0, s_pidx = cb->args[2];
struct net_bridge *br = netdev_priv(dev);
struct net_bridge_mdb_entry *mp;
struct nlattr *nest, *nest2;
if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
return 0;
nest = nla_nest_start_noflag(skb, MDBA_MDB);
if (nest == NULL)
return -EMSGSIZE;
hlist_for_each_entry_rcu(mp, &br->mdb_list, mdb_node) {
struct net_bridge_port_group *p;
struct net_bridge_port_group __rcu **pp;
if (idx < s_idx)
goto skip;
nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
if (!nest2) {
err = -EMSGSIZE;
break;
}
if (!s_pidx && mp->host_joined) {
err = __mdb_fill_info(skb, mp, NULL);
if (err) {
nla_nest_cancel(skb, nest2);
break;
}
}
for (pp = &mp->ports; (p = rcu_dereference(*pp)) != NULL;
pp = &p->next) {
if (!p->key.port)
continue;
if (pidx < s_pidx)
goto skip_pg;
err = __mdb_fill_info(skb, mp, p);
if (err) {
nla_nest_end(skb, nest2);
goto out;
}
skip_pg:
pidx++;
}
pidx = 0;
s_pidx = 0;
nla_nest_end(skb, nest2);
skip:
idx++;
}
out:
cb->args[1] = idx;
cb->args[2] = pidx;
nla_nest_end(skb, nest);
return err;
}
static int br_mdb_valid_dump_req(const struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct br_port_msg *bpm;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*bpm))) {
NL_SET_ERR_MSG_MOD(extack, "Invalid header for mdb dump request");
return -EINVAL;
}
bpm = nlmsg_data(nlh);
if (bpm->ifindex) {
NL_SET_ERR_MSG_MOD(extack, "Filtering by device index is not supported for mdb dump request");
return -EINVAL;
}
if (nlmsg_attrlen(nlh, sizeof(*bpm))) {
NL_SET_ERR_MSG(extack, "Invalid data after header in mdb dump request");
return -EINVAL;
}
return 0;
}
static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net_device *dev;
struct net *net = sock_net(skb->sk);
struct nlmsghdr *nlh = NULL;
int idx = 0, s_idx;
if (cb->strict_check) {
int err = br_mdb_valid_dump_req(cb->nlh, cb->extack);
if (err < 0)
return err;
}
s_idx = cb->args[0];
rcu_read_lock();
cb->seq = net->dev_base_seq;
for_each_netdev_rcu(net, dev) {
if (dev->priv_flags & IFF_EBRIDGE) {
struct br_port_msg *bpm;
if (idx < s_idx)
goto skip;
nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, RTM_GETMDB,
sizeof(*bpm), NLM_F_MULTI);
if (nlh == NULL)
break;
bpm = nlmsg_data(nlh);
memset(bpm, 0, sizeof(*bpm));
bpm->ifindex = dev->ifindex;
if (br_mdb_fill_info(skb, cb, dev) < 0)
goto out;
if (br_rports_fill_info(skb, cb, dev) < 0)
goto out;
cb->args[1] = 0;
nlmsg_end(skb, nlh);
skip:
idx++;
}
}
out:
if (nlh)
nlmsg_end(skb, nlh);
rcu_read_unlock();
cb->args[0] = idx;
return skb->len;
}
static int nlmsg_populate_mdb_fill(struct sk_buff *skb,
struct net_device *dev,
struct net_bridge_mdb_entry *mp,
struct net_bridge_port_group *pg,
int type)
{
struct nlmsghdr *nlh;
struct br_port_msg *bpm;
struct nlattr *nest, *nest2;
nlh = nlmsg_put(skb, 0, 0, type, sizeof(*bpm), 0);
if (!nlh)
return -EMSGSIZE;
bpm = nlmsg_data(nlh);
memset(bpm, 0, sizeof(*bpm));
bpm->family = AF_BRIDGE;
bpm->ifindex = dev->ifindex;
nest = nla_nest_start_noflag(skb, MDBA_MDB);
if (nest == NULL)
goto cancel;
nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
if (nest2 == NULL)
goto end;
if (__mdb_fill_info(skb, mp, pg))
goto end;
nla_nest_end(skb, nest2);
nla_nest_end(skb, nest);
nlmsg_end(skb, nlh);
return 0;
end:
nla_nest_end(skb, nest);
cancel:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static size_t rtnl_mdb_nlmsg_size(struct net_bridge_port_group *pg)
{
size_t nlmsg_size = NLMSG_ALIGN(sizeof(struct br_port_msg)) +
nla_total_size(sizeof(struct br_mdb_entry)) +
nla_total_size(sizeof(u32));
struct net_bridge_group_src *ent;
size_t addr_size = 0;
if (!pg)
goto out;
/* MDBA_MDB_EATTR_RTPROT */
nlmsg_size += nla_total_size(sizeof(u8));
switch (pg->key.addr.proto) {
case htons(ETH_P_IP):
/* MDBA_MDB_EATTR_SOURCE */
if (pg->key.addr.src.ip4)
nlmsg_size += nla_total_size(sizeof(__be32));
if (pg->key.port->br->multicast_igmp_version == 2)
goto out;
addr_size = sizeof(__be32);
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
/* MDBA_MDB_EATTR_SOURCE */
if (!ipv6_addr_any(&pg->key.addr.src.ip6))
nlmsg_size += nla_total_size(sizeof(struct in6_addr));
if (pg->key.port->br->multicast_mld_version == 1)
goto out;
addr_size = sizeof(struct in6_addr);
break;
#endif
}
/* MDBA_MDB_EATTR_GROUP_MODE */
nlmsg_size += nla_total_size(sizeof(u8));
/* MDBA_MDB_EATTR_SRC_LIST nested attr */
if (!hlist_empty(&pg->src_list))
nlmsg_size += nla_total_size(0);
hlist_for_each_entry(ent, &pg->src_list, node) {
/* MDBA_MDB_SRCLIST_ENTRY nested attr +
* MDBA_MDB_SRCATTR_ADDRESS + MDBA_MDB_SRCATTR_TIMER
*/
nlmsg_size += nla_total_size(0) +
nla_total_size(addr_size) +
nla_total_size(sizeof(u32));
}
out:
return nlmsg_size;
}
struct br_mdb_complete_info {
struct net_bridge_port *port;
struct br_ip ip;
};
static void br_mdb_complete(struct net_device *dev, int err, void *priv)
{
struct br_mdb_complete_info *data = priv;
struct net_bridge_port_group __rcu **pp;
struct net_bridge_port_group *p;
struct net_bridge_mdb_entry *mp;
struct net_bridge_port *port = data->port;
struct net_bridge *br = port->br;
if (err)
goto err;
spin_lock_bh(&br->multicast_lock);
mp = br_mdb_ip_get(br, &data->ip);
if (!mp)
goto out;
for (pp = &mp->ports; (p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (p->key.port != port)
continue;
p->flags |= MDB_PG_FLAGS_OFFLOAD;
}
out:
spin_unlock_bh(&br->multicast_lock);
err:
kfree(priv);
}
static void br_switchdev_mdb_populate(struct switchdev_obj_port_mdb *mdb,
const struct net_bridge_mdb_entry *mp)
{
if (mp->addr.proto == htons(ETH_P_IP))
ip_eth_mc_map(mp->addr.dst.ip4, mdb->addr);
#if IS_ENABLED(CONFIG_IPV6)
else if (mp->addr.proto == htons(ETH_P_IPV6))
ipv6_eth_mc_map(&mp->addr.dst.ip6, mdb->addr);
#endif
else
ether_addr_copy(mdb->addr, mp->addr.dst.mac_addr);
mdb->vid = mp->addr.vid;
}
static int br_mdb_replay_one(struct notifier_block *nb, struct net_device *dev,
struct switchdev_obj_port_mdb *mdb,
struct netlink_ext_ack *extack)
{
struct switchdev_notifier_port_obj_info obj_info = {
.info = {
.dev = dev,
.extack = extack,
},
.obj = &mdb->obj,
};
int err;
err = nb->notifier_call(nb, SWITCHDEV_PORT_OBJ_ADD, &obj_info);
return notifier_to_errno(err);
}
static int br_mdb_queue_one(struct list_head *mdb_list,
enum switchdev_obj_id id,
const struct net_bridge_mdb_entry *mp,
struct net_device *orig_dev)
{
struct switchdev_obj_port_mdb *mdb;
mdb = kzalloc(sizeof(*mdb), GFP_ATOMIC);
if (!mdb)
return -ENOMEM;
mdb->obj.id = id;
mdb->obj.orig_dev = orig_dev;
br_switchdev_mdb_populate(mdb, mp);
list_add_tail(&mdb->obj.list, mdb_list);
return 0;
}
int br_mdb_replay(struct net_device *br_dev, struct net_device *dev,
struct notifier_block *nb, struct netlink_ext_ack *extack)
{
struct net_bridge_mdb_entry *mp;
struct switchdev_obj *obj, *tmp;
struct net_bridge *br;
LIST_HEAD(mdb_list);
int err = 0;
ASSERT_RTNL();
if (!netif_is_bridge_master(br_dev) || !netif_is_bridge_port(dev))
return -EINVAL;
br = netdev_priv(br_dev);
if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
return 0;
/* We cannot walk over br->mdb_list protected just by the rtnl_mutex,
* because the write-side protection is br->multicast_lock. But we
* need to emulate the [ blocking ] calling context of a regular
* switchdev event, so since both br->multicast_lock and RCU read side
* critical sections are atomic, we have no choice but to pick the RCU
* read side lock, queue up all our events, leave the critical section
* and notify switchdev from blocking context.
*/
rcu_read_lock();
hlist_for_each_entry_rcu(mp, &br->mdb_list, mdb_node) {
struct net_bridge_port_group __rcu **pp;
struct net_bridge_port_group *p;
if (mp->host_joined) {
err = br_mdb_queue_one(&mdb_list,
SWITCHDEV_OBJ_ID_HOST_MDB,
mp, br_dev);
if (err) {
rcu_read_unlock();
goto out_free_mdb;
}
}
for (pp = &mp->ports; (p = rcu_dereference(*pp)) != NULL;
pp = &p->next) {
if (p->key.port->dev != dev)
continue;
err = br_mdb_queue_one(&mdb_list,
SWITCHDEV_OBJ_ID_PORT_MDB,
mp, dev);
if (err) {
rcu_read_unlock();
goto out_free_mdb;
}
}
}
rcu_read_unlock();
list_for_each_entry(obj, &mdb_list, list) {
err = br_mdb_replay_one(nb, dev, SWITCHDEV_OBJ_PORT_MDB(obj),
extack);
if (err)
goto out_free_mdb;
}
out_free_mdb:
list_for_each_entry_safe(obj, tmp, &mdb_list, list) {
list_del(&obj->list);
kfree(SWITCHDEV_OBJ_PORT_MDB(obj));
}
return err;
}
EXPORT_SYMBOL_GPL(br_mdb_replay);
static void br_mdb_switchdev_host_port(struct net_device *dev,
struct net_device *lower_dev,
struct net_bridge_mdb_entry *mp,
int type)
{
struct switchdev_obj_port_mdb mdb = {
.obj = {
.id = SWITCHDEV_OBJ_ID_HOST_MDB,
.flags = SWITCHDEV_F_DEFER,
.orig_dev = dev,
},
};
br_switchdev_mdb_populate(&mdb, mp);
switch (type) {
case RTM_NEWMDB:
switchdev_port_obj_add(lower_dev, &mdb.obj, NULL);
break;
case RTM_DELMDB:
switchdev_port_obj_del(lower_dev, &mdb.obj);
break;
}
}
static void br_mdb_switchdev_host(struct net_device *dev,
struct net_bridge_mdb_entry *mp, int type)
{
struct net_device *lower_dev;
struct list_head *iter;
netdev_for_each_lower_dev(dev, lower_dev, iter)
br_mdb_switchdev_host_port(dev, lower_dev, mp, type);
}
void br_mdb_notify(struct net_device *dev,
struct net_bridge_mdb_entry *mp,
struct net_bridge_port_group *pg,
int type)
{
struct br_mdb_complete_info *complete_info;
struct switchdev_obj_port_mdb mdb = {
.obj = {
.id = SWITCHDEV_OBJ_ID_PORT_MDB,
.flags = SWITCHDEV_F_DEFER,
},
};
struct net *net = dev_net(dev);
struct sk_buff *skb;
int err = -ENOBUFS;
if (pg) {
br_switchdev_mdb_populate(&mdb, mp);
mdb.obj.orig_dev = pg->key.port->dev;
switch (type) {
case RTM_NEWMDB:
complete_info = kmalloc(sizeof(*complete_info), GFP_ATOMIC);
if (!complete_info)
break;
complete_info->port = pg->key.port;
complete_info->ip = mp->addr;
mdb.obj.complete_priv = complete_info;
mdb.obj.complete = br_mdb_complete;
if (switchdev_port_obj_add(pg->key.port->dev, &mdb.obj, NULL))
kfree(complete_info);
break;
case RTM_DELMDB:
switchdev_port_obj_del(pg->key.port->dev, &mdb.obj);
break;
}
} else {
br_mdb_switchdev_host(dev, mp, type);
}
skb = nlmsg_new(rtnl_mdb_nlmsg_size(pg), GFP_ATOMIC);
if (!skb)
goto errout;
err = nlmsg_populate_mdb_fill(skb, dev, mp, pg, type);
if (err < 0) {
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
return;
errout:
rtnl_set_sk_err(net, RTNLGRP_MDB, err);
}
static int nlmsg_populate_rtr_fill(struct sk_buff *skb,
struct net_device *dev,
int ifindex, u32 pid,
u32 seq, int type, unsigned int flags)
{
struct br_port_msg *bpm;
struct nlmsghdr *nlh;
struct nlattr *nest;
nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), 0);
if (!nlh)
return -EMSGSIZE;
bpm = nlmsg_data(nlh);
memset(bpm, 0, sizeof(*bpm));
bpm->family = AF_BRIDGE;
bpm->ifindex = dev->ifindex;
nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
if (!nest)
goto cancel;
if (nla_put_u32(skb, MDBA_ROUTER_PORT, ifindex))
goto end;
nla_nest_end(skb, nest);
nlmsg_end(skb, nlh);
return 0;
end:
nla_nest_end(skb, nest);
cancel:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
static inline size_t rtnl_rtr_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct br_port_msg))
+ nla_total_size(sizeof(__u32));
}
void br_rtr_notify(struct net_device *dev, struct net_bridge_port *port,
int type)
{
struct net *net = dev_net(dev);
struct sk_buff *skb;
int err = -ENOBUFS;
int ifindex;
ifindex = port ? port->dev->ifindex : 0;
skb = nlmsg_new(rtnl_rtr_nlmsg_size(), GFP_ATOMIC);
if (!skb)
goto errout;
err = nlmsg_populate_rtr_fill(skb, dev, ifindex, 0, 0, type, NTF_SELF);
if (err < 0) {
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
return;
errout:
rtnl_set_sk_err(net, RTNLGRP_MDB, err);
}
static bool is_valid_mdb_entry(struct br_mdb_entry *entry,
struct netlink_ext_ack *extack)
{
if (entry->ifindex == 0) {
NL_SET_ERR_MSG_MOD(extack, "Zero entry ifindex is not allowed");
return false;
}
if (entry->addr.proto == htons(ETH_P_IP)) {
if (!ipv4_is_multicast(entry->addr.u.ip4)) {
NL_SET_ERR_MSG_MOD(extack, "IPv4 entry group address is not multicast");
return false;
}
if (ipv4_is_local_multicast(entry->addr.u.ip4)) {
NL_SET_ERR_MSG_MOD(extack, "IPv4 entry group address is local multicast");
return false;
}
#if IS_ENABLED(CONFIG_IPV6)
} else if (entry->addr.proto == htons(ETH_P_IPV6)) {
if (ipv6_addr_is_ll_all_nodes(&entry->addr.u.ip6)) {
NL_SET_ERR_MSG_MOD(extack, "IPv6 entry group address is link-local all nodes");
return false;
}
#endif
} else if (entry->addr.proto == 0) {
/* L2 mdb */
if (!is_multicast_ether_addr(entry->addr.u.mac_addr)) {
NL_SET_ERR_MSG_MOD(extack, "L2 entry group is not multicast");
return false;
}
} else {
NL_SET_ERR_MSG_MOD(extack, "Unknown entry protocol");
return false;
}
if (entry->state != MDB_PERMANENT && entry->state != MDB_TEMPORARY) {
NL_SET_ERR_MSG_MOD(extack, "Unknown entry state");
return false;
}
if (entry->vid >= VLAN_VID_MASK) {
NL_SET_ERR_MSG_MOD(extack, "Invalid entry VLAN id");
return false;
}
return true;
}
static bool is_valid_mdb_source(struct nlattr *attr, __be16 proto,
struct netlink_ext_ack *extack)
{
switch (proto) {
case htons(ETH_P_IP):
if (nla_len(attr) != sizeof(struct in_addr)) {
NL_SET_ERR_MSG_MOD(extack, "IPv4 invalid source address length");
return false;
}
if (ipv4_is_multicast(nla_get_in_addr(attr))) {
NL_SET_ERR_MSG_MOD(extack, "IPv4 multicast source address is not allowed");
return false;
}
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6): {
struct in6_addr src;
if (nla_len(attr) != sizeof(struct in6_addr)) {
NL_SET_ERR_MSG_MOD(extack, "IPv6 invalid source address length");
return false;
}
src = nla_get_in6_addr(attr);
if (ipv6_addr_is_multicast(&src)) {
NL_SET_ERR_MSG_MOD(extack, "IPv6 multicast source address is not allowed");
return false;
}
break;
}
#endif
default:
NL_SET_ERR_MSG_MOD(extack, "Invalid protocol used with source address");
return false;
}
return true;
}
static const struct nla_policy br_mdbe_attrs_pol[MDBE_ATTR_MAX + 1] = {
[MDBE_ATTR_SOURCE] = NLA_POLICY_RANGE(NLA_BINARY,
sizeof(struct in_addr),
sizeof(struct in6_addr)),
};
static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh,
struct net_device **pdev, struct br_mdb_entry **pentry,
struct nlattr **mdb_attrs, struct netlink_ext_ack *extack)
{
struct net *net = sock_net(skb->sk);
struct br_mdb_entry *entry;
struct br_port_msg *bpm;
struct nlattr *tb[MDBA_SET_ENTRY_MAX+1];
struct net_device *dev;
int err;
err = nlmsg_parse_deprecated(nlh, sizeof(*bpm), tb,
MDBA_SET_ENTRY_MAX, NULL, NULL);
if (err < 0)
return err;
bpm = nlmsg_data(nlh);
if (bpm->ifindex == 0) {
NL_SET_ERR_MSG_MOD(extack, "Invalid bridge ifindex");
return -EINVAL;
}
dev = __dev_get_by_index(net, bpm->ifindex);
if (dev == NULL) {
NL_SET_ERR_MSG_MOD(extack, "Bridge device doesn't exist");
return -ENODEV;
}
if (!(dev->priv_flags & IFF_EBRIDGE)) {
NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge");
return -EOPNOTSUPP;
}
*pdev = dev;
if (!tb[MDBA_SET_ENTRY]) {
NL_SET_ERR_MSG_MOD(extack, "Missing MDBA_SET_ENTRY attribute");
return -EINVAL;
}
if (nla_len(tb[MDBA_SET_ENTRY]) != sizeof(struct br_mdb_entry)) {
NL_SET_ERR_MSG_MOD(extack, "Invalid MDBA_SET_ENTRY attribute length");
return -EINVAL;
}
entry = nla_data(tb[MDBA_SET_ENTRY]);
if (!is_valid_mdb_entry(entry, extack))
return -EINVAL;
*pentry = entry;
if (tb[MDBA_SET_ENTRY_ATTRS]) {
err = nla_parse_nested(mdb_attrs, MDBE_ATTR_MAX,
tb[MDBA_SET_ENTRY_ATTRS],
br_mdbe_attrs_pol, extack);
if (err)
return err;
if (mdb_attrs[MDBE_ATTR_SOURCE] &&
!is_valid_mdb_source(mdb_attrs[MDBE_ATTR_SOURCE],
entry->addr.proto, extack))
return -EINVAL;
} else {
memset(mdb_attrs, 0,
sizeof(struct nlattr *) * (MDBE_ATTR_MAX + 1));
}
return 0;
}
static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port,
struct br_mdb_entry *entry,
struct nlattr **mdb_attrs,
struct netlink_ext_ack *extack)
{
struct net_bridge_mdb_entry *mp, *star_mp;
struct net_bridge_port_group *p;
struct net_bridge_port_group __rcu **pp;
struct br_ip group, star_group;
unsigned long now = jiffies;
unsigned char flags = 0;
u8 filter_mode;
int err;
__mdb_entry_to_br_ip(entry, &group, mdb_attrs);
/* host join errors which can happen before creating the group */
if (!port) {
/* don't allow any flags for host-joined groups */
if (entry->state) {
NL_SET_ERR_MSG_MOD(extack, "Flags are not allowed for host groups");
return -EINVAL;
}
if (!br_multicast_is_star_g(&group)) {
NL_SET_ERR_MSG_MOD(extack, "Groups with sources cannot be manually host joined");
return -EINVAL;
}
}
if (br_group_is_l2(&group) && entry->state != MDB_PERMANENT) {
NL_SET_ERR_MSG_MOD(extack, "Only permanent L2 entries allowed");
return -EINVAL;
}
mp = br_mdb_ip_get(br, &group);
if (!mp) {
mp = br_multicast_new_group(br, &group);
err = PTR_ERR_OR_ZERO(mp);
if (err)
return err;
}
/* host join */
if (!port) {
if (mp->host_joined) {
NL_SET_ERR_MSG_MOD(extack, "Group is already joined by host");
return -EEXIST;
}
br_multicast_host_join(mp, false);
br_mdb_notify(br->dev, mp, NULL, RTM_NEWMDB);
return 0;
}
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (p->key.port == port) {
NL_SET_ERR_MSG_MOD(extack, "Group is already joined by port");
return -EEXIST;
}
if ((unsigned long)p->key.port < (unsigned long)port)
break;
}
filter_mode = br_multicast_is_star_g(&group) ? MCAST_EXCLUDE :
MCAST_INCLUDE;
if (entry->state == MDB_PERMANENT)
flags |= MDB_PG_FLAGS_PERMANENT;
p = br_multicast_new_port_group(port, &group, *pp, flags, NULL,
filter_mode, RTPROT_STATIC);
if (unlikely(!p)) {
NL_SET_ERR_MSG_MOD(extack, "Couldn't allocate new port group");
return -ENOMEM;
}
rcu_assign_pointer(*pp, p);
if (entry->state == MDB_TEMPORARY)
mod_timer(&p->timer, now + br->multicast_membership_interval);
br_mdb_notify(br->dev, mp, p, RTM_NEWMDB);
/* if we are adding a new EXCLUDE port group (*,G) it needs to be also
* added to all S,G entries for proper replication, if we are adding
* a new INCLUDE port (S,G) then all of *,G EXCLUDE ports need to be
* added to it for proper replication
*/
if (br_multicast_should_handle_mode(br, group.proto)) {
switch (filter_mode) {
case MCAST_EXCLUDE:
br_multicast_star_g_handle_mode(p, MCAST_EXCLUDE);
break;
case MCAST_INCLUDE:
star_group = p->key.addr;
memset(&star_group.src, 0, sizeof(star_group.src));
star_mp = br_mdb_ip_get(br, &star_group);
if (star_mp)
br_multicast_sg_add_exclude_ports(star_mp, p);
break;
}
}
return 0;
}
static int __br_mdb_add(struct net *net, struct net_bridge *br,
struct net_bridge_port *p,
struct br_mdb_entry *entry,
struct nlattr **mdb_attrs,
struct netlink_ext_ack *extack)
{
int ret;
spin_lock_bh(&br->multicast_lock);
ret = br_mdb_add_group(br, p, entry, mdb_attrs, extack);
spin_unlock_bh(&br->multicast_lock);
return ret;
}
static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct nlattr *mdb_attrs[MDBE_ATTR_MAX + 1];
struct net *net = sock_net(skb->sk);
struct net_bridge_vlan_group *vg;
struct net_bridge_port *p = NULL;
struct net_device *dev, *pdev;
struct br_mdb_entry *entry;
struct net_bridge_vlan *v;
struct net_bridge *br;
int err;
err = br_mdb_parse(skb, nlh, &dev, &entry, mdb_attrs, extack);
if (err < 0)
return err;
br = netdev_priv(dev);
if (!netif_running(br->dev)) {
NL_SET_ERR_MSG_MOD(extack, "Bridge device is not running");
return -EINVAL;
}
if (!br_opt_get(br, BROPT_MULTICAST_ENABLED)) {
NL_SET_ERR_MSG_MOD(extack, "Bridge's multicast processing is disabled");
return -EINVAL;
}
if (entry->ifindex != br->dev->ifindex) {
pdev = __dev_get_by_index(net, entry->ifindex);
if (!pdev) {
NL_SET_ERR_MSG_MOD(extack, "Port net device doesn't exist");
return -ENODEV;
}
p = br_port_get_rtnl(pdev);
if (!p) {
NL_SET_ERR_MSG_MOD(extack, "Net device is not a bridge port");
return -EINVAL;
}
if (p->br != br) {
NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
return -EINVAL;
}
if (p->state == BR_STATE_DISABLED) {
NL_SET_ERR_MSG_MOD(extack, "Port is in disabled state");
return -EINVAL;
}
vg = nbp_vlan_group(p);
} else {
vg = br_vlan_group(br);
}
/* If vlan filtering is enabled and VLAN is not specified
* install mdb entry on all vlans configured on the port.
*/
if (br_vlan_enabled(br->dev) && vg && entry->vid == 0) {
list_for_each_entry(v, &vg->vlan_list, vlist) {
entry->vid = v->vid;
err = __br_mdb_add(net, br, p, entry, mdb_attrs, extack);
if (err)
break;
}
} else {
err = __br_mdb_add(net, br, p, entry, mdb_attrs, extack);
}
return err;
}
static int __br_mdb_del(struct net_bridge *br, struct br_mdb_entry *entry,
struct nlattr **mdb_attrs)
{
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
struct net_bridge_port_group __rcu **pp;
struct br_ip ip;
int err = -EINVAL;
if (!netif_running(br->dev) || !br_opt_get(br, BROPT_MULTICAST_ENABLED))
return -EINVAL;
__mdb_entry_to_br_ip(entry, &ip, mdb_attrs);
spin_lock_bh(&br->multicast_lock);
mp = br_mdb_ip_get(br, &ip);
if (!mp)
goto unlock;
/* host leave */
if (entry->ifindex == mp->br->dev->ifindex && mp->host_joined) {
br_multicast_host_leave(mp, false);
err = 0;
br_mdb_notify(br->dev, mp, NULL, RTM_DELMDB);
if (!mp->ports && netif_running(br->dev))
mod_timer(&mp->timer, jiffies);
goto unlock;
}
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (!p->key.port || p->key.port->dev->ifindex != entry->ifindex)
continue;
if (p->key.port->state == BR_STATE_DISABLED)
goto unlock;
br_multicast_del_pg(mp, p, pp);
err = 0;
break;
}
unlock:
spin_unlock_bh(&br->multicast_lock);
return err;
}
static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct nlattr *mdb_attrs[MDBE_ATTR_MAX + 1];
struct net *net = sock_net(skb->sk);
struct net_bridge_vlan_group *vg;
struct net_bridge_port *p = NULL;
struct net_device *dev, *pdev;
struct br_mdb_entry *entry;
struct net_bridge_vlan *v;
struct net_bridge *br;
int err;
err = br_mdb_parse(skb, nlh, &dev, &entry, mdb_attrs, extack);
if (err < 0)
return err;
br = netdev_priv(dev);
if (entry->ifindex != br->dev->ifindex) {
pdev = __dev_get_by_index(net, entry->ifindex);
if (!pdev)
return -ENODEV;
p = br_port_get_rtnl(pdev);
if (!p || p->br != br || p->state == BR_STATE_DISABLED)
return -EINVAL;
vg = nbp_vlan_group(p);
} else {
vg = br_vlan_group(br);
}
/* If vlan filtering is enabled and VLAN is not specified
* delete mdb entry on all vlans configured on the port.
*/
if (br_vlan_enabled(br->dev) && vg && entry->vid == 0) {
list_for_each_entry(v, &vg->vlan_list, vlist) {
entry->vid = v->vid;
err = __br_mdb_del(br, entry, mdb_attrs);
}
} else {
err = __br_mdb_del(br, entry, mdb_attrs);
}
return err;
}
void br_mdb_init(void)
{
rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, 0);
rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_NEWMDB, br_mdb_add, NULL, 0);
rtnl_register_module(THIS_MODULE, PF_BRIDGE, RTM_DELMDB, br_mdb_del, NULL, 0);
}
void br_mdb_uninit(void)
{
rtnl_unregister(PF_BRIDGE, RTM_GETMDB);
rtnl_unregister(PF_BRIDGE, RTM_NEWMDB);
rtnl_unregister(PF_BRIDGE, RTM_DELMDB);
}