linux/net/bridge/br_mdb.c
Nikolay Aleksandrov 59f78f9f6c bridge: mcast: add support for more router port information dumping
Allow for more multicast router port information to be dumped such as
timer and type attributes. For that that purpose we need to extend the
MDBA_ROUTER_PORT attribute similar to how it was done for the mdb entries
recently. The new format is thus:
[MDBA_ROUTER_PORT] = { <- nested attribute
    u32 ifindex <- router port ifindex for user-space compatibility
    [MDBA_ROUTER_PATTR attributes]
}
This way it remains compatible with older users (they'll simply retrieve
the u32 in the beginning) and new users can parse the remaining
attributes. It would also allow to add future extensions to the router
port without breaking compatibility.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01 16:55:07 -05:00

689 lines
16 KiB
C

#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 int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
struct net_bridge_port *p;
struct nlattr *nest, *port_nest;
if (!br->multicast_router || hlist_empty(&br->router_list))
return 0;
nest = nla_nest_start(skb, MDBA_ROUTER);
if (nest == NULL)
return -EMSGSIZE;
hlist_for_each_entry_rcu(p, &br->router_list, rlist) {
if (!p)
continue;
port_nest = nla_nest_start(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,
br_timer_value(&p->multicast_router_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;
}
static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
struct net_bridge_mdb_htable *mdb;
struct nlattr *nest, *nest2;
int i, err = 0;
int idx = 0, s_idx = cb->args[1];
if (br->multicast_disabled)
return 0;
mdb = rcu_dereference(br->mdb);
if (!mdb)
return 0;
nest = nla_nest_start(skb, MDBA_MDB);
if (nest == NULL)
return -EMSGSIZE;
for (i = 0; i < mdb->max; i++) {
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
struct net_bridge_port_group __rcu **pp;
struct net_bridge_port *port;
hlist_for_each_entry_rcu(mp, &mdb->mhash[i], hlist[mdb->ver]) {
if (idx < s_idx)
goto skip;
nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY);
if (nest2 == NULL) {
err = -EMSGSIZE;
goto out;
}
for (pp = &mp->ports;
(p = rcu_dereference(*pp)) != NULL;
pp = &p->next) {
struct nlattr *nest_ent;
struct br_mdb_entry e;
port = p->port;
if (!port)
continue;
memset(&e, 0, sizeof(e));
e.ifindex = port->dev->ifindex;
e.vid = p->addr.vid;
__mdb_entry_fill_flags(&e, p->flags);
if (p->addr.proto == htons(ETH_P_IP))
e.addr.u.ip4 = p->addr.u.ip4;
#if IS_ENABLED(CONFIG_IPV6)
if (p->addr.proto == htons(ETH_P_IPV6))
e.addr.u.ip6 = p->addr.u.ip6;
#endif
e.addr.proto = p->addr.proto;
nest_ent = nla_nest_start(skb,
MDBA_MDB_ENTRY_INFO);
if (!nest_ent) {
nla_nest_cancel(skb, nest2);
err = -EMSGSIZE;
goto out;
}
if (nla_put_nohdr(skb, sizeof(e), &e) ||
nla_put_u32(skb,
MDBA_MDB_EATTR_TIMER,
br_timer_value(&p->timer))) {
nla_nest_cancel(skb, nest_ent);
nla_nest_cancel(skb, nest2);
err = -EMSGSIZE;
goto out;
}
nla_nest_end(skb, nest_ent);
}
nla_nest_end(skb, nest2);
skip:
idx++;
}
}
out:
cb->args[1] = idx;
nla_nest_end(skb, nest);
return err;
}
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;
s_idx = cb->args[0];
rcu_read_lock();
/* In theory this could be wrapped to 0... */
cb->seq = net->dev_base_seq + br_mdb_rehash_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 br_mdb_entry *entry, u32 pid,
u32 seq, int type, unsigned int flags)
{
struct nlmsghdr *nlh;
struct br_port_msg *bpm;
struct nlattr *nest, *nest2;
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(skb, MDBA_MDB);
if (nest == NULL)
goto cancel;
nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY);
if (nest2 == NULL)
goto end;
if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(*entry), entry))
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 inline size_t rtnl_mdb_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct br_port_msg))
+ nla_total_size(sizeof(struct br_mdb_entry));
}
static void __br_mdb_notify(struct net_device *dev, struct br_mdb_entry *entry,
int type, struct net_bridge_port_group *pg)
{
struct switchdev_obj_port_mdb mdb = {
.obj = {
.id = SWITCHDEV_OBJ_ID_PORT_MDB,
.flags = SWITCHDEV_F_DEFER,
},
.vid = entry->vid,
};
struct net_device *port_dev;
struct net *net = dev_net(dev);
struct sk_buff *skb;
int err = -ENOBUFS;
port_dev = __dev_get_by_index(net, entry->ifindex);
if (entry->addr.proto == htons(ETH_P_IP))
ip_eth_mc_map(entry->addr.u.ip4, mdb.addr);
#if IS_ENABLED(CONFIG_IPV6)
else
ipv6_eth_mc_map(&entry->addr.u.ip6, mdb.addr);
#endif
mdb.obj.orig_dev = port_dev;
if (port_dev && type == RTM_NEWMDB) {
err = switchdev_port_obj_add(port_dev, &mdb.obj);
if (!err && pg)
pg->flags |= MDB_PG_FLAGS_OFFLOAD;
} else if (port_dev && type == RTM_DELMDB) {
switchdev_port_obj_del(port_dev, &mdb.obj);
}
skb = nlmsg_new(rtnl_mdb_nlmsg_size(), GFP_ATOMIC);
if (!skb)
goto errout;
err = nlmsg_populate_mdb_fill(skb, dev, entry, 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);
}
void br_mdb_notify(struct net_device *dev, struct net_bridge_port_group *pg,
int type)
{
struct br_mdb_entry entry;
memset(&entry, 0, sizeof(entry));
entry.ifindex = pg->port->dev->ifindex;
entry.addr.proto = pg->addr.proto;
entry.addr.u.ip4 = pg->addr.u.ip4;
#if IS_ENABLED(CONFIG_IPV6)
entry.addr.u.ip6 = pg->addr.u.ip6;
#endif
entry.vid = pg->addr.vid;
__mdb_entry_fill_flags(&entry, pg->flags);
__br_mdb_notify(dev, &entry, type, pg);
}
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), NLM_F_MULTI);
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(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)
{
if (entry->ifindex == 0)
return false;
if (entry->addr.proto == htons(ETH_P_IP)) {
if (!ipv4_is_multicast(entry->addr.u.ip4))
return false;
if (ipv4_is_local_multicast(entry->addr.u.ip4))
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))
return false;
#endif
} else
return false;
if (entry->state != MDB_PERMANENT && entry->state != MDB_TEMPORARY)
return false;
if (entry->vid >= VLAN_VID_MASK)
return false;
return true;
}
static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh,
struct net_device **pdev, struct br_mdb_entry **pentry)
{
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(nlh, sizeof(*bpm), tb, MDBA_SET_ENTRY_MAX, NULL);
if (err < 0)
return err;
bpm = nlmsg_data(nlh);
if (bpm->ifindex == 0) {
pr_info("PF_BRIDGE: br_mdb_parse() with invalid ifindex\n");
return -EINVAL;
}
dev = __dev_get_by_index(net, bpm->ifindex);
if (dev == NULL) {
pr_info("PF_BRIDGE: br_mdb_parse() with unknown ifindex\n");
return -ENODEV;
}
if (!(dev->priv_flags & IFF_EBRIDGE)) {
pr_info("PF_BRIDGE: br_mdb_parse() with non-bridge\n");
return -EOPNOTSUPP;
}
*pdev = dev;
if (!tb[MDBA_SET_ENTRY] ||
nla_len(tb[MDBA_SET_ENTRY]) != sizeof(struct br_mdb_entry)) {
pr_info("PF_BRIDGE: br_mdb_parse() with invalid attr\n");
return -EINVAL;
}
entry = nla_data(tb[MDBA_SET_ENTRY]);
if (!is_valid_mdb_entry(entry)) {
pr_info("PF_BRIDGE: br_mdb_parse() with invalid entry\n");
return -EINVAL;
}
*pentry = entry;
return 0;
}
static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port,
struct br_ip *group, unsigned char state,
struct net_bridge_port_group **pg)
{
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
struct net_bridge_port_group __rcu **pp;
struct net_bridge_mdb_htable *mdb;
unsigned long now = jiffies;
int err;
mdb = mlock_dereference(br->mdb, br);
mp = br_mdb_ip_get(mdb, group);
if (!mp) {
mp = br_multicast_new_group(br, port, group);
err = PTR_ERR_OR_ZERO(mp);
if (err)
return err;
}
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (p->port == port)
return -EEXIST;
if ((unsigned long)p->port < (unsigned long)port)
break;
}
p = br_multicast_new_port_group(port, group, *pp, state);
if (unlikely(!p))
return -ENOMEM;
rcu_assign_pointer(*pp, p);
*pg = p;
if (state == MDB_TEMPORARY)
mod_timer(&p->timer, now + br->multicast_membership_interval);
return 0;
}
static int __br_mdb_add(struct net *net, struct net_bridge *br,
struct br_mdb_entry *entry,
struct net_bridge_port_group **pg)
{
struct br_ip ip;
struct net_device *dev;
struct net_bridge_port *p;
int ret;
if (!netif_running(br->dev) || br->multicast_disabled)
return -EINVAL;
dev = __dev_get_by_index(net, entry->ifindex);
if (!dev)
return -ENODEV;
p = br_port_get_rtnl(dev);
if (!p || p->br != br || p->state == BR_STATE_DISABLED)
return -EINVAL;
memset(&ip, 0, sizeof(ip));
ip.vid = entry->vid;
ip.proto = entry->addr.proto;
if (ip.proto == htons(ETH_P_IP))
ip.u.ip4 = entry->addr.u.ip4;
#if IS_ENABLED(CONFIG_IPV6)
else
ip.u.ip6 = entry->addr.u.ip6;
#endif
spin_lock_bh(&br->multicast_lock);
ret = br_mdb_add_group(br, p, &ip, entry->state, pg);
spin_unlock_bh(&br->multicast_lock);
return ret;
}
static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct net *net = sock_net(skb->sk);
struct net_bridge_port_group *pg;
struct net_bridge_vlan_group *vg;
struct net_device *dev, *pdev;
struct br_mdb_entry *entry;
struct net_bridge_port *p;
struct net_bridge_vlan *v;
struct net_bridge *br;
int err;
err = br_mdb_parse(skb, nlh, &dev, &entry);
if (err < 0)
return err;
br = netdev_priv(dev);
/* If vlan filtering is enabled and VLAN is not specified
* install mdb entry on all vlans configured on the port.
*/
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);
if (br_vlan_enabled(br) && vg && entry->vid == 0) {
list_for_each_entry(v, &vg->vlan_list, vlist) {
entry->vid = v->vid;
err = __br_mdb_add(net, br, entry, &pg);
if (err)
break;
__br_mdb_notify(dev, entry, RTM_NEWMDB, pg);
}
} else {
err = __br_mdb_add(net, br, entry, &pg);
if (!err)
__br_mdb_notify(dev, entry, RTM_NEWMDB, pg);
}
return err;
}
static int __br_mdb_del(struct net_bridge *br, struct br_mdb_entry *entry)
{
struct net_bridge_mdb_htable *mdb;
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->multicast_disabled)
return -EINVAL;
memset(&ip, 0, sizeof(ip));
ip.vid = entry->vid;
ip.proto = entry->addr.proto;
if (ip.proto == htons(ETH_P_IP))
ip.u.ip4 = entry->addr.u.ip4;
#if IS_ENABLED(CONFIG_IPV6)
else
ip.u.ip6 = entry->addr.u.ip6;
#endif
spin_lock_bh(&br->multicast_lock);
mdb = mlock_dereference(br->mdb, br);
mp = br_mdb_ip_get(mdb, &ip);
if (!mp)
goto unlock;
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
if (!p->port || p->port->dev->ifindex != entry->ifindex)
continue;
if (p->port->state == BR_STATE_DISABLED)
goto unlock;
__mdb_entry_fill_flags(entry, p->flags);
rcu_assign_pointer(*pp, p->next);
hlist_del_init(&p->mglist);
del_timer(&p->timer);
call_rcu_bh(&p->rcu, br_multicast_free_pg);
err = 0;
if (!mp->ports && !mp->mglist &&
netif_running(br->dev))
mod_timer(&mp->timer, jiffies);
break;
}
unlock:
spin_unlock_bh(&br->multicast_lock);
return err;
}
static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct net *net = sock_net(skb->sk);
struct net_bridge_vlan_group *vg;
struct net_device *dev, *pdev;
struct br_mdb_entry *entry;
struct net_bridge_port *p;
struct net_bridge_vlan *v;
struct net_bridge *br;
int err;
err = br_mdb_parse(skb, nlh, &dev, &entry);
if (err < 0)
return err;
br = netdev_priv(dev);
/* If vlan filtering is enabled and VLAN is not specified
* delete mdb entry on all vlans configured on the port.
*/
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);
if (br_vlan_enabled(br) && vg && entry->vid == 0) {
list_for_each_entry(v, &vg->vlan_list, vlist) {
entry->vid = v->vid;
err = __br_mdb_del(br, entry);
if (!err)
__br_mdb_notify(dev, entry, RTM_DELMDB, NULL);
}
} else {
err = __br_mdb_del(br, entry);
if (!err)
__br_mdb_notify(dev, entry, RTM_DELMDB, NULL);
}
return err;
}
void br_mdb_init(void)
{
rtnl_register(PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, NULL);
rtnl_register(PF_BRIDGE, RTM_NEWMDB, br_mdb_add, NULL, NULL);
rtnl_register(PF_BRIDGE, RTM_DELMDB, br_mdb_del, NULL, NULL);
}
void br_mdb_uninit(void)
{
rtnl_unregister(PF_BRIDGE, RTM_GETMDB);
rtnl_unregister(PF_BRIDGE, RTM_NEWMDB);
rtnl_unregister(PF_BRIDGE, RTM_DELMDB);
}