linux/net/bridge/br_netlink.c
Vlad Yasevich e028e4b8dc bridge: Keep track of ports capable of automatic discovery.
By default, ports on the bridge are capable of automatic
discovery of nodes located behind the port.  This is accomplished
via flooding of unknown traffic (BR_FLOOD) and learning the
mac addresses from these packets (BR_LEARNING).
If the above functionality is disabled by turning off these
flags, the port requires static configuration in the form
of static FDB entries to function properly.

This patch adds functionality to keep track of all ports
capable of automatic discovery.  This will later be used
to control promiscuity settings.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16 17:06:33 -04:00

522 lines
13 KiB
C

/*
* Bridge netlink control interface
*
* Authors:
* Stephen Hemminger <shemminger@osdl.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/etherdevice.h>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <uapi/linux/if_bridge.h>
#include "br_private.h"
#include "br_private_stp.h"
static inline size_t br_port_info_size(void)
{
return nla_total_size(1) /* IFLA_BRPORT_STATE */
+ nla_total_size(2) /* IFLA_BRPORT_PRIORITY */
+ nla_total_size(4) /* IFLA_BRPORT_COST */
+ nla_total_size(1) /* IFLA_BRPORT_MODE */
+ nla_total_size(1) /* IFLA_BRPORT_GUARD */
+ nla_total_size(1) /* IFLA_BRPORT_PROTECT */
+ nla_total_size(1) /* IFLA_BRPORT_FAST_LEAVE */
+ nla_total_size(1) /* IFLA_BRPORT_LEARNING */
+ nla_total_size(1) /* IFLA_BRPORT_UNICAST_FLOOD */
+ 0;
}
static inline size_t br_nlmsg_size(void)
{
return NLMSG_ALIGN(sizeof(struct ifinfomsg))
+ nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
+ nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
+ nla_total_size(4) /* IFLA_MASTER */
+ nla_total_size(4) /* IFLA_MTU */
+ nla_total_size(4) /* IFLA_LINK */
+ nla_total_size(1) /* IFLA_OPERSTATE */
+ nla_total_size(br_port_info_size()); /* IFLA_PROTINFO */
}
static int br_port_fill_attrs(struct sk_buff *skb,
const struct net_bridge_port *p)
{
u8 mode = !!(p->flags & BR_HAIRPIN_MODE);
if (nla_put_u8(skb, IFLA_BRPORT_STATE, p->state) ||
nla_put_u16(skb, IFLA_BRPORT_PRIORITY, p->priority) ||
nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) ||
nla_put_u8(skb, IFLA_BRPORT_MODE, mode) ||
nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) ||
nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) ||
nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE)) ||
nla_put_u8(skb, IFLA_BRPORT_LEARNING, !!(p->flags & BR_LEARNING)) ||
nla_put_u8(skb, IFLA_BRPORT_UNICAST_FLOOD, !!(p->flags & BR_FLOOD)))
return -EMSGSIZE;
return 0;
}
/*
* Create one netlink message for one interface
* Contains port and master info as well as carrier and bridge state.
*/
static int br_fill_ifinfo(struct sk_buff *skb,
const struct net_bridge_port *port,
u32 pid, u32 seq, int event, unsigned int flags,
u32 filter_mask, const struct net_device *dev)
{
const struct net_bridge *br;
struct ifinfomsg *hdr;
struct nlmsghdr *nlh;
u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;
if (port)
br = port->br;
else
br = netdev_priv(dev);
br_debug(br, "br_fill_info event %d port %s master %s\n",
event, dev->name, br->dev->name);
nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags);
if (nlh == NULL)
return -EMSGSIZE;
hdr = nlmsg_data(nlh);
hdr->ifi_family = AF_BRIDGE;
hdr->__ifi_pad = 0;
hdr->ifi_type = dev->type;
hdr->ifi_index = dev->ifindex;
hdr->ifi_flags = dev_get_flags(dev);
hdr->ifi_change = 0;
if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
nla_put_u32(skb, IFLA_MASTER, br->dev->ifindex) ||
nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
nla_put_u8(skb, IFLA_OPERSTATE, operstate) ||
(dev->addr_len &&
nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
(dev->ifindex != dev->iflink &&
nla_put_u32(skb, IFLA_LINK, dev->iflink)))
goto nla_put_failure;
if (event == RTM_NEWLINK && port) {
struct nlattr *nest
= nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED);
if (nest == NULL || br_port_fill_attrs(skb, port) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
}
/* Check if the VID information is requested */
if (filter_mask & RTEXT_FILTER_BRVLAN) {
struct nlattr *af;
const struct net_port_vlans *pv;
struct bridge_vlan_info vinfo;
u16 vid;
u16 pvid;
if (port)
pv = nbp_get_vlan_info(port);
else
pv = br_get_vlan_info(br);
if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID))
goto done;
af = nla_nest_start(skb, IFLA_AF_SPEC);
if (!af)
goto nla_put_failure;
pvid = br_get_pvid(pv);
for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
vinfo.vid = vid;
vinfo.flags = 0;
if (vid == pvid)
vinfo.flags |= BRIDGE_VLAN_INFO_PVID;
if (test_bit(vid, pv->untagged_bitmap))
vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED;
if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO,
sizeof(vinfo), &vinfo))
goto nla_put_failure;
}
nla_nest_end(skb, af);
}
done:
return nlmsg_end(skb, nlh);
nla_put_failure:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
/*
* Notify listeners of a change in port information
*/
void br_ifinfo_notify(int event, struct net_bridge_port *port)
{
struct net *net;
struct sk_buff *skb;
int err = -ENOBUFS;
if (!port)
return;
net = dev_net(port->dev);
br_debug(port->br, "port %u(%s) event %d\n",
(unsigned int)port->port_no, port->dev->name, event);
skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC);
if (skb == NULL)
goto errout;
err = br_fill_ifinfo(skb, port, 0, 0, event, 0, 0, port->dev);
if (err < 0) {
/* -EMSGSIZE implies BUG in br_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
kfree_skb(skb);
goto errout;
}
rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC);
return;
errout:
rtnl_set_sk_err(net, RTNLGRP_LINK, err);
}
/*
* Dump information about all ports, in response to GETLINK
*/
int br_getlink(struct sk_buff *skb, u32 pid, u32 seq,
struct net_device *dev, u32 filter_mask)
{
int err = 0;
struct net_bridge_port *port = br_port_get_rtnl(dev);
/* not a bridge port and */
if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN))
goto out;
err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI,
filter_mask, dev);
out:
return err;
}
static const struct nla_policy ifla_br_policy[IFLA_MAX+1] = {
[IFLA_BRIDGE_FLAGS] = { .type = NLA_U16 },
[IFLA_BRIDGE_MODE] = { .type = NLA_U16 },
[IFLA_BRIDGE_VLAN_INFO] = { .type = NLA_BINARY,
.len = sizeof(struct bridge_vlan_info), },
};
static int br_afspec(struct net_bridge *br,
struct net_bridge_port *p,
struct nlattr *af_spec,
int cmd)
{
struct nlattr *tb[IFLA_BRIDGE_MAX+1];
int err = 0;
err = nla_parse_nested(tb, IFLA_BRIDGE_MAX, af_spec, ifla_br_policy);
if (err)
return err;
if (tb[IFLA_BRIDGE_VLAN_INFO]) {
struct bridge_vlan_info *vinfo;
vinfo = nla_data(tb[IFLA_BRIDGE_VLAN_INFO]);
if (!vinfo->vid || vinfo->vid >= VLAN_VID_MASK)
return -EINVAL;
switch (cmd) {
case RTM_SETLINK:
if (p) {
err = nbp_vlan_add(p, vinfo->vid, vinfo->flags);
if (err)
break;
if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER)
err = br_vlan_add(p->br, vinfo->vid,
vinfo->flags);
} else
err = br_vlan_add(br, vinfo->vid, vinfo->flags);
if (err)
break;
break;
case RTM_DELLINK:
if (p) {
nbp_vlan_delete(p, vinfo->vid);
if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER)
br_vlan_delete(p->br, vinfo->vid);
} else
br_vlan_delete(br, vinfo->vid);
break;
}
}
return err;
}
static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = {
[IFLA_BRPORT_STATE] = { .type = NLA_U8 },
[IFLA_BRPORT_COST] = { .type = NLA_U32 },
[IFLA_BRPORT_PRIORITY] = { .type = NLA_U16 },
[IFLA_BRPORT_MODE] = { .type = NLA_U8 },
[IFLA_BRPORT_GUARD] = { .type = NLA_U8 },
[IFLA_BRPORT_PROTECT] = { .type = NLA_U8 },
[IFLA_BRPORT_LEARNING] = { .type = NLA_U8 },
[IFLA_BRPORT_UNICAST_FLOOD] = { .type = NLA_U8 },
};
/* Change the state of the port and notify spanning tree */
static int br_set_port_state(struct net_bridge_port *p, u8 state)
{
if (state > BR_STATE_BLOCKING)
return -EINVAL;
/* if kernel STP is running, don't allow changes */
if (p->br->stp_enabled == BR_KERNEL_STP)
return -EBUSY;
/* if device is not up, change is not allowed
* if link is not present, only allowable state is disabled
*/
if (!netif_running(p->dev) ||
(!netif_oper_up(p->dev) && state != BR_STATE_DISABLED))
return -ENETDOWN;
p->state = state;
br_log_state(p);
br_port_state_selection(p->br);
return 0;
}
/* Set/clear or port flags based on attribute */
static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
int attrtype, unsigned long mask)
{
if (tb[attrtype]) {
u8 flag = nla_get_u8(tb[attrtype]);
if (flag)
p->flags |= mask;
else
p->flags &= ~mask;
}
}
/* Process bridge protocol info on port */
static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
{
int err;
unsigned long old_flags = p->flags;
br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE);
br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
if (tb[IFLA_BRPORT_COST]) {
err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST]));
if (err)
return err;
}
if (tb[IFLA_BRPORT_PRIORITY]) {
err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY]));
if (err)
return err;
}
if (tb[IFLA_BRPORT_STATE]) {
err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE]));
if (err)
return err;
}
br_port_flags_change(p, old_flags ^ p->flags);
return 0;
}
/* Change state and parameters on port. */
int br_setlink(struct net_device *dev, struct nlmsghdr *nlh)
{
struct nlattr *protinfo;
struct nlattr *afspec;
struct net_bridge_port *p;
struct nlattr *tb[IFLA_BRPORT_MAX + 1];
int err = 0;
protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_PROTINFO);
afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC);
if (!protinfo && !afspec)
return 0;
p = br_port_get_rtnl(dev);
/* We want to accept dev as bridge itself if the AF_SPEC
* is set to see if someone is setting vlan info on the bridge
*/
if (!p && !afspec)
return -EINVAL;
if (p && protinfo) {
if (protinfo->nla_type & NLA_F_NESTED) {
err = nla_parse_nested(tb, IFLA_BRPORT_MAX,
protinfo, ifla_brport_policy);
if (err)
return err;
spin_lock_bh(&p->br->lock);
err = br_setport(p, tb);
spin_unlock_bh(&p->br->lock);
} else {
/* Binary compatibility with old RSTP */
if (nla_len(protinfo) < sizeof(u8))
return -EINVAL;
spin_lock_bh(&p->br->lock);
err = br_set_port_state(p, nla_get_u8(protinfo));
spin_unlock_bh(&p->br->lock);
}
if (err)
goto out;
}
if (afspec) {
err = br_afspec((struct net_bridge *)netdev_priv(dev), p,
afspec, RTM_SETLINK);
}
if (err == 0)
br_ifinfo_notify(RTM_NEWLINK, p);
out:
return err;
}
/* Delete port information */
int br_dellink(struct net_device *dev, struct nlmsghdr *nlh)
{
struct nlattr *afspec;
struct net_bridge_port *p;
int err;
afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC);
if (!afspec)
return 0;
p = br_port_get_rtnl(dev);
/* We want to accept dev as bridge itself as well */
if (!p && !(dev->priv_flags & IFF_EBRIDGE))
return -EINVAL;
err = br_afspec((struct net_bridge *)netdev_priv(dev), p,
afspec, RTM_DELLINK);
return err;
}
static int br_validate(struct nlattr *tb[], struct nlattr *data[])
{
if (tb[IFLA_ADDRESS]) {
if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
return -EINVAL;
if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
return -EADDRNOTAVAIL;
}
return 0;
}
static int br_dev_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct net_bridge *br = netdev_priv(dev);
if (tb[IFLA_ADDRESS]) {
spin_lock_bh(&br->lock);
br_stp_change_bridge_id(br, nla_data(tb[IFLA_ADDRESS]));
spin_unlock_bh(&br->lock);
}
return register_netdevice(dev);
}
static size_t br_get_link_af_size(const struct net_device *dev)
{
struct net_port_vlans *pv;
if (br_port_exists(dev))
pv = nbp_get_vlan_info(br_port_get_rtnl(dev));
else if (dev->priv_flags & IFF_EBRIDGE)
pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev));
else
return 0;
if (!pv)
return 0;
/* Each VLAN is returned in bridge_vlan_info along with flags */
return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info));
}
static struct rtnl_af_ops br_af_ops = {
.family = AF_BRIDGE,
.get_link_af_size = br_get_link_af_size,
};
struct rtnl_link_ops br_link_ops __read_mostly = {
.kind = "bridge",
.priv_size = sizeof(struct net_bridge),
.setup = br_dev_setup,
.validate = br_validate,
.newlink = br_dev_newlink,
.dellink = br_dev_delete,
};
int __init br_netlink_init(void)
{
int err;
br_mdb_init();
rtnl_af_register(&br_af_ops);
err = rtnl_link_register(&br_link_ops);
if (err)
goto out_af;
return 0;
out_af:
rtnl_af_unregister(&br_af_ops);
br_mdb_uninit();
return err;
}
void __exit br_netlink_fini(void)
{
br_mdb_uninit();
rtnl_af_unregister(&br_af_ops);
rtnl_link_unregister(&br_link_ops);
}