2 * Copyright (c) 2009, 2010, 2013 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
19 #include "rtnetlink-link.h"
21 #include <sys/socket.h>
22 #include <linux/rtnetlink.h>
26 #include "netlink-notifier.h"
29 static struct nln
*nln
= NULL
;
30 static struct rtnetlink_link_change rtn_change
;
32 /* Parses a rtnetlink message 'buf' into 'change'. If 'buf' is unparseable,
33 * leaves 'change' untouched and returns false. Otherwise, populates 'change'
34 * and returns true. */
36 rtnetlink_link_parse(struct ofpbuf
*buf
,
37 struct rtnetlink_link_change
*change
)
41 /* Policy for RTNLGRP_LINK messages.
43 * There are *many* more fields in these messages, but currently we
44 * only care about these fields. */
45 static const struct nl_policy policy
[] = {
46 [IFLA_IFNAME
] = { .type
= NL_A_STRING
, .optional
= false },
47 [IFLA_MASTER
] = { .type
= NL_A_U32
, .optional
= true },
48 [IFLA_MTU
] = { .type
= NL_A_U32
, .optional
= true },
49 [IFLA_ADDRESS
] = { .type
= NL_A_UNSPEC
, .optional
= true },
52 struct nlattr
*attrs
[ARRAY_SIZE(policy
)];
54 parsed
= nl_policy_parse(buf
, NLMSG_HDRLEN
+ sizeof(struct ifinfomsg
),
55 policy
, attrs
, ARRAY_SIZE(policy
));
58 const struct nlmsghdr
*nlmsg
;
59 const struct ifinfomsg
*ifinfo
;
61 nlmsg
= ofpbuf_data(buf
);
62 ifinfo
= ofpbuf_at(buf
, NLMSG_HDRLEN
, sizeof *ifinfo
);
64 change
->nlmsg_type
= nlmsg
->nlmsg_type
;
65 change
->ifi_index
= ifinfo
->ifi_index
;
66 change
->ifname
= nl_attr_get_string(attrs
[IFLA_IFNAME
]);
67 change
->ifi_flags
= ifinfo
->ifi_flags
;
68 change
->master_ifindex
= (attrs
[IFLA_MASTER
]
69 ? nl_attr_get_u32(attrs
[IFLA_MASTER
])
71 change
->mtu
= (attrs
[IFLA_MTU
]
72 ? nl_attr_get_u32(attrs
[IFLA_MTU
])
75 if (attrs
[IFLA_ADDRESS
] &&
76 nl_attr_get_size(attrs
[IFLA_ADDRESS
]) == ETH_ALEN
) {
77 memcpy(change
->addr
, nl_attr_get(attrs
[IFLA_ADDRESS
]), ETH_ALEN
);
79 memset(change
->addr
, 0, ETH_ALEN
);
87 rtnetlink_link_parse_cb(struct ofpbuf
*buf
, void *change
)
89 return rtnetlink_link_parse(buf
, change
);
92 /* Registers 'cb' to be called with auxiliary data 'aux' with network device
93 * change notifications. The notifier is stored in 'notifier', which the
94 * caller must not modify or free.
96 * This is probably not the function that you want. You should probably be
97 * using dpif_port_poll() or netdev_change_seq(), which unlike this function
98 * are not Linux-specific.
100 * Returns an initialized nln_notifier if successful, NULL otherwise. */
101 struct nln_notifier
*
102 rtnetlink_link_notifier_create(rtnetlink_link_notify_func
*cb
, void *aux
)
105 nln
= nln_create(NETLINK_ROUTE
, RTNLGRP_LINK
, rtnetlink_link_parse_cb
,
109 return nln_notifier_create(nln
, (nln_notify_func
*) cb
, aux
);
112 /* Destroys 'notifier', which must have previously been created with
113 * rtnetlink_link_notifier_register(). */
115 rtnetlink_link_notifier_destroy(struct nln_notifier
*notifier
)
117 nln_notifier_destroy(notifier
);
120 /* Calls all of the registered notifiers, passing along any as-yet-unreported
121 * netdev change events. */
123 rtnetlink_link_run(void)
130 /* Causes poll_block() to wake up when network device change notifications are
133 rtnetlink_link_wait(void)