4 This file is part of avahi.
6 avahi is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as
8 published by the Free Software Foundation; either version 2.1 of the
9 License, or (at your option) any later version.
11 avahi is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
14 Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with avahi; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
31 #include <avahi-common/malloc.h>
35 #include "iface-linux.h"
37 static int netlink_list_items(AvahiNetlink *nl, uint16_t type, unsigned *ret_seq) {
42 memset(&req, 0, sizeof(req));
43 n = (struct nlmsghdr*) req;
44 n->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
46 n->nlmsg_flags = NLM_F_ROOT|NLM_F_REQUEST;
50 memset(gen, 0, sizeof(struct rtgenmsg));
51 gen->rtgen_family = AF_UNSPEC;
53 return avahi_netlink_send(nl, n, ret_seq);
56 static void netlink_callback(AvahiNetlink *nl, struct nlmsghdr *n, void* userdata) {
57 AvahiInterfaceMonitor *m = userdata;
61 assert(m->osdep.netlink == nl);
63 if (n->nlmsg_type == RTM_NEWLINK) {
64 struct ifinfomsg *ifinfomsg = NLMSG_DATA(n);
66 struct rtattr *a = NULL;
69 if (ifinfomsg->ifi_family != AF_UNSPEC)
72 /* Check whether there already is an AvahiHwInterface object
73 * for this link, so that we can update its data. Note that
74 * Netlink sends us an RTM_NEWLINK not only when a new
75 * interface appears, but when it changes, too */
77 if (!(hw = avahi_interface_monitor_get_hw_interface(m, ifinfomsg->ifi_index)))
79 /* No object found, so let's create a new
80 * one. avahi_hw_interface_new() will call
81 * avahi_interface_new() internally twice for IPv4 and
82 * IPv6, so there is no need for us to do that
84 if (!(hw = avahi_hw_interface_new(m, (AvahiIfIndex) ifinfomsg->ifi_index)))
87 /* Check whether the flags of this interface are OK for us */
89 (ifinfomsg->ifi_flags & IFF_UP) &&
90 (!m->server->config.use_iff_running || (ifinfomsg->ifi_flags & IFF_RUNNING)) &&
91 !(ifinfomsg->ifi_flags & IFF_LOOPBACK) &&
92 (ifinfomsg->ifi_flags & IFF_MULTICAST) &&
93 !(ifinfomsg->ifi_flags & IFF_POINTOPOINT);
95 /* Handle interface attributes */
96 l = NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg));
97 a = IFLA_RTA(ifinfomsg);
99 while (RTA_OK(a, l)) {
100 switch(a->rta_type) {
103 /* Fill in interface name */
104 avahi_free(hw->name);
105 hw->name = avahi_strndup(RTA_DATA(a), RTA_PAYLOAD(a));
111 assert(RTA_PAYLOAD(a) == sizeof(unsigned int));
112 hw->mtu = *((unsigned int*) RTA_DATA(a));
117 /* Fill in hardware (MAC) address */
118 hw->mac_address_size = RTA_PAYLOAD(a);
119 if (hw->mac_address_size > AVAHI_MAX_MAC_ADDRESS)
120 hw->mac_address_size = AVAHI_MAX_MAC_ADDRESS;
122 memcpy(hw->mac_address, RTA_DATA(a), hw->mac_address_size);
132 /* Check whether this interface is now "relevant" for us. If
133 * it is Avahi will start to announce its records on this
134 * interface and send out queries for subscribed records on
136 avahi_hw_interface_check_relevant(hw);
138 /* Update any associated RRs of this interface. (i.e. the
139 * _workstation._tcp record containing the MAC address) */
140 avahi_hw_interface_update_rrs(hw, 0);
142 } else if (n->nlmsg_type == RTM_DELLINK) {
143 struct ifinfomsg *ifinfomsg = NLMSG_DATA(n);
144 AvahiHwInterface *hw;
146 if (ifinfomsg->ifi_family != AF_UNSPEC)
149 /* Get a reference to our AvahiHwInterface object of this interface */
150 if (!(hw = avahi_interface_monitor_get_hw_interface(m, (AvahiIfIndex) ifinfomsg->ifi_index)))
153 /* Free our object */
154 avahi_hw_interface_free(hw, 0);
156 } else if (n->nlmsg_type == RTM_NEWADDR || n->nlmsg_type == RTM_DELADDR) {
158 struct ifaddrmsg *ifaddrmsg = NLMSG_DATA(n);
160 struct rtattr *a = NULL;
165 /* We are only interested in IPv4 and IPv6 */
166 if (ifaddrmsg->ifa_family != AF_INET && ifaddrmsg->ifa_family != AF_INET6)
169 /* Try to get a reference to our AvahiInterface object for the
170 * interface this address is assigned to. If ther is no object
171 * for this interface, we ignore this address. */
172 if (!(i = avahi_interface_monitor_get_interface(m, (AvahiIfIndex) ifaddrmsg->ifa_index, avahi_af_to_proto(ifaddrmsg->ifa_family))))
175 /* Fill in address family for our new address */
176 raddr.proto = avahi_af_to_proto(ifaddrmsg->ifa_family);
178 l = NLMSG_PAYLOAD(n, sizeof(struct ifaddrmsg));
179 a = IFA_RTA(ifaddrmsg);
181 while (RTA_OK(a, l)) {
183 switch(a->rta_type) {
185 /* Fill in address data */
187 if ((raddr.proto == AVAHI_PROTO_INET6 && RTA_PAYLOAD(a) != 16) ||
188 (raddr.proto == AVAHI_PROTO_INET && RTA_PAYLOAD(a) != 4))
191 memcpy(raddr.data.data, RTA_DATA(a), RTA_PAYLOAD(a));
203 /* If there was no adress attached to this message, let's quit. */
207 if (n->nlmsg_type == RTM_NEWADDR) {
208 AvahiInterfaceAddress *addr;
210 /* This address is new or has been modified, so let's get an object for it */
211 if (!(addr = avahi_interface_monitor_get_address(m, i, &raddr)))
213 /* Mmm, no object existing yet, so let's create a new one */
214 if (!(addr = avahi_interface_address_new(m, i, &raddr, ifaddrmsg->ifa_prefixlen)))
217 /* Update the scope field for the address */
218 addr->global_scope = ifaddrmsg->ifa_scope == RT_SCOPE_UNIVERSE || ifaddrmsg->ifa_scope == RT_SCOPE_SITE;
220 AvahiInterfaceAddress *addr;
221 assert(n->nlmsg_type == RTM_DELADDR);
223 /* Try to get a reference to our AvahiInterfaceAddress object for this address */
224 if (!(addr = avahi_interface_monitor_get_address(m, i, &raddr)))
228 avahi_interface_address_free(addr);
231 /* Avahi only considers interfaces with at least one address
232 * attached relevant. Since we migh have added or removed an
233 * address, let's have it check again whether the interface is
235 avahi_interface_check_relevant(i);
237 /* Update any associated RRs, like A or AAAA for our new/removed address */
238 avahi_interface_update_rrs(i, 0);
240 } else if (n->nlmsg_type == NLMSG_DONE) {
242 /* This wild dump request ended, so let's see what we do next */
244 if (m->osdep.list == LIST_IFACE) {
246 /* Mmmm, interfaces have been wild dumped already, so
247 * let's go on with wild dumping the addresses */
249 if (netlink_list_items(m->osdep.netlink, RTM_GETADDR, &m->osdep.query_addr_seq) < 0) {
250 avahi_log_warn("NETLINK: Failed to list addrs: %s", strerror(errno));
251 m->osdep.list = LIST_DONE;
254 /* Update state information */
255 m->osdep.list = LIST_ADDR;
258 /* We're done. Tell avahi_interface_monitor_sync() to finish. */
259 m->osdep.list = LIST_DONE;
261 if (m->osdep.list == LIST_DONE) {
263 /* Only after this boolean variable has been set, Avahi
264 * will start to announce or browse on all interfaces. It
265 * is originaly set to 0, which means that relevancy
266 * checks and RR updates are disabled during the wild
268 m->list_complete = 1;
270 /* So let's check if any interfaces are relevant now */
271 avahi_interface_monitor_check_relevant(m);
273 /* And update all RRs attached to any interface */
274 avahi_interface_monitor_update_rrs(m, 0);
276 /* Tell the user that the wild dump is complete */
277 avahi_log_info("Network interface enumeration completed.");
280 } else if (n->nlmsg_type == NLMSG_ERROR &&
281 (n->nlmsg_seq == m->osdep.query_link_seq || n->nlmsg_seq == m->osdep.query_addr_seq)) {
282 struct nlmsgerr *e = NLMSG_DATA (n);
284 /* Some kind of error happened. Let's just tell the user and
285 * ignore it otherwise */
288 avahi_log_warn("NETLINK: Failed to browse: %s", strerror(-e->error));
292 int avahi_interface_monitor_init_osdep(AvahiInterfaceMonitor *m) {
295 /* Initialize our own data */
297 m->osdep.netlink = NULL;
298 m->osdep.query_addr_seq = m->osdep.query_link_seq = 0;
300 /* Create a netlink object for us. It abstracts some things and
301 * makes netlink easier to use. It will attach to the main loop
302 * for us and call netlink_callback() whenever an event
304 if (!(m->osdep.netlink = avahi_netlink_new(m->server->poll_api, RTMGRP_LINK|RTMGRP_IPV4_IFADDR|RTMGRP_IPV6_IFADDR, netlink_callback, m)))
307 /* Start the wild dump for the interfaces */
308 if (netlink_list_items(m->osdep.netlink, RTM_GETLINK, &m->osdep.query_link_seq) < 0)
311 /* Set the initial state. */
312 m->osdep.list = LIST_IFACE;
318 if (m->osdep.netlink) {
319 avahi_netlink_free(m->osdep.netlink);
320 m->osdep.netlink = NULL;
326 void avahi_interface_monitor_free_osdep(AvahiInterfaceMonitor *m) {
329 if (m->osdep.netlink) {
330 avahi_netlink_free(m->osdep.netlink);
331 m->osdep.netlink = NULL;
335 void avahi_interface_monitor_sync(AvahiInterfaceMonitor *m) {
338 /* Let's handle netlink events until we are done with wild
341 while (m->osdep.list != LIST_DONE) {
342 if (!avahi_netlink_work(m->osdep.netlink, 1) == 0)
346 /* At this point Avahi knows about all local interfaces and
347 * addresses in existance. */