1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*
* 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 <net/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include "br_private.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;
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);
if (dev->addr_len)
NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
if (dev->ifindex != dev->iflink)
NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
if (event == RTM_NEWLINK)
NLA_PUT_U8(skb, IFLA_PROTINFO, port->state);
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)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;
for_each_netdev(net, dev) {
/* not a bridge port */
if (!br_port_exists(dev) || idx < cb->args[0])
goto skip;
if (br_fill_ifinfo(skb, br_port_get(dev),
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWLINK,
NLM_F_MULTI) < 0)
break;
skip:
++idx;
}
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;
if (!br_port_exists(dev))
return -EINVAL;
p = br_port_get(dev);
/* 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);
return 0;
}
int __init br_netlink_init(void)
{
if (__rtnl_register(PF_BRIDGE, RTM_GETLINK, NULL, br_dump_ifinfo))
return -ENOBUFS;
/* Only the first call to __rtnl_register can fail */
__rtnl_register(PF_BRIDGE, RTM_SETLINK, br_rtm_setlink, NULL);
return 0;
}
void __exit br_netlink_fini(void)
{
rtnl_unregister_all(PF_BRIDGE);
}
|
