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/*
* 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 "br_private.h"
#include "br_private_stp.h"
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(1); /* IFLA_PROTINFO */
}
/*
* 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)
{
const struct net_bridge *br = port->br;
const struct net_device *dev = port->dev;
struct ifinfomsg *hdr;
struct nlmsghdr *nlh;
u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;
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)) ||
(event == RTM_NEWLINK &&
nla_put_u8(skb, IFLA_PROTINFO, port->state)))
goto nla_put_failure;
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 = dev_net(port->dev);
struct sk_buff *skb;
int err = -ENOBUFS;
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);
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:
if (err < 0)
rtnl_set_sk_err(net, RTNLGRP_LINK, err);
}
/*
* Dump information about all ports, in response to GETLINK
*/
static int br_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct net_device *dev;
int idx;
idx = 0;
rcu_read_lock();
for_each_netdev_rcu(net, dev) {
struct net_bridge_port *port = br_port_get_rcu(dev);
/* not a bridge port */
if (!port || idx < cb->args[0])
goto skip;
if (br_fill_ifinfo(skb, port,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWLINK,
NLM_F_MULTI) < 0)
break;
skip:
++idx;
}
rcu_read_unlock();
cb->args[0] = idx;
return skb->len;
}
/*
* Change state of port (ie from forwarding to blocking etc)
* Used by spanning tree in user space.
*/
static int br_rtm_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
struct ifinfomsg *ifm;
struct nlattr *protinfo;
struct net_device *dev;
struct net_bridge_port *p;
u8 new_state;
if (nlmsg_len(nlh) < sizeof(*ifm))
return -EINVAL;
ifm = nlmsg_data(nlh);
if (ifm->ifi_family != AF_BRIDGE)
return -EPFNOSUPPORT;
protinfo = nlmsg_find_attr(nlh, sizeof(*ifm), IFLA_PROTINFO);
if (!protinfo || nla_len(protinfo) < sizeof(u8))
return -EINVAL;
new_state = nla_get_u8(protinfo);
if (new_state > BR_STATE_BLOCKING)
return -EINVAL;
dev = __dev_get_by_index(net, ifm->ifi_index);
if (!dev)
return -ENODEV;
p = br_port_get_rtnl(dev);
if (!p)
return -EINVAL;
/* if kernel STP is running, don't allow changes */
if (p->br->stp_enabled == BR_KERNEL_STP)
return -EBUSY;
if (!netif_running(dev) ||
(!netif_carrier_ok(dev) && new_state != BR_STATE_DISABLED))
return -ENETDOWN;
p->state = new_state;
br_log_state(p);
spin_lock_bh(&p->br->lock);
br_port_state_selection(p->br);
spin_unlock_bh(&p->br->lock);
br_ifinfo_notify(RTM_NEWLINK, p);
return 0;
}
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;
}
struct rtnl_link_ops br_link_ops __read_mostly = {
.kind = "bridge",
.priv_size = sizeof(struct net_bridge),
.setup = br_dev_setup,
.validate = br_validate,
.dellink = br_dev_delete,
};
int __init br_netlink_init(void)
{
int err;
err = rtnl_link_register(&br_link_ops);
if (err < 0)
goto err1;
err = __rtnl_register(PF_BRIDGE, RTM_GETLINK, NULL,
br_dump_ifinfo, NULL);
if (err)
goto err2;
err = __rtnl_register(PF_BRIDGE, RTM_SETLINK,
br_rtm_setlink, NULL, NULL);
if (err)
goto err3;
return 0;
err3:
rtnl_unregister_all(PF_BRIDGE);
err2:
rtnl_link_unregister(&br_link_ops);
err1:
return err;
}
void __exit br_netlink_fini(void)
{
rtnl_link_unregister(&br_link_ops);
rtnl_unregister_all(PF_BRIDGE);
}
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