1 /*
2 * net/tipc/eth_media.c: Ethernet bearer support for TIPC
3 *
4 * Copyright (c) 2001-2007, Ericsson AB
5 * Copyright (c) 2005-2007, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include <net/tipc/tipc.h>
38 #include <net/tipc/tipc_bearer.h>
39 #include <net/tipc/tipc_msg.h>
40 #include <linux/netdevice.h>
41 #include <net/net_namespace.h>
42
43 #define MAX_ETH_BEARERS 2
44 #define ETH_LINK_PRIORITY TIPC_DEF_LINK_PRI
45 #define ETH_LINK_TOLERANCE TIPC_DEF_LINK_TOL
46 #define ETH_LINK_WINDOW TIPC_DEF_LINK_WIN
47
48 /**
49 * struct eth_bearer - Ethernet bearer data structure
50 * @bearer: ptr to associated "generic" bearer structure
51 * @dev: ptr to associated Ethernet network device
52 * @tipc_packet_type: used in binding TIPC to Ethernet driver
53 */
54
55 struct eth_bearer {
56 struct tipc_bearer *bearer;
57 struct net_device *dev;
58 struct packet_type tipc_packet_type;
59 };
60
61 static struct eth_bearer eth_bearers[MAX_ETH_BEARERS];
62 static int eth_started = 0;
63 static struct notifier_block notifier;
64
65 /**
66 * send_msg - send a TIPC message out over an Ethernet interface
67 */
68
69 static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
70 struct tipc_media_addr *dest)
71 {
72 struct sk_buff *clone;
73 struct net_device *dev;
74
75 clone = skb_clone(buf, GFP_ATOMIC);
76 if (clone) {
77 skb_reset_network_header(clone);
78 dev = ((struct eth_bearer *)(tb_ptr->usr_handle))->dev;
79 clone->dev = dev;
80 dev_hard_header(clone, dev, ETH_P_TIPC,
81 &dest->dev_addr.eth_addr,
82 dev->dev_addr, clone->len);
83 dev_queue_xmit(clone);
84 }
85 return 0;
86 }
87
88 /**
89 * recv_msg - handle incoming TIPC message from an Ethernet interface
90 *
91 * Accept only packets explicitly sent to this node, or broadcast packets;
92 * ignores packets sent using Ethernet multicast, and traffic sent to other
93 * nodes (which can happen if interface is running in promiscuous mode).
94 * Routine truncates any Ethernet padding/CRC appended to the message,
95 * and ensures message size matches actual length
96 */
97
98 static int recv_msg(struct sk_buff *buf, struct net_device *dev,
99 struct packet_type *pt, struct net_device *orig_dev)
100 {
101 struct eth_bearer *eb_ptr = (struct eth_bearer *)pt->af_packet_priv;
102 u32 size;
103
104 if (!net_eq(dev_net(dev), &init_net)) {
105 kfree_skb(buf);
106 return 0;
107 }
108
109 if (likely(eb_ptr->bearer)) {
110 if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
111 size = msg_size((struct tipc_msg *)buf->data);
112 skb_trim(buf, size);
113 if (likely(buf->len == size)) {
114 buf->next = NULL;
115 tipc_recv_msg(buf, eb_ptr->bearer);
116 return 0;
117 }
118 }
119 }
120 kfree_skb(buf);
121 return 0;
122 }
123
124 /**
125 * enable_bearer - attach TIPC bearer to an Ethernet interface
126 */
127
128 static int enable_bearer(struct tipc_bearer *tb_ptr)
129 {
130 struct net_device *dev = NULL;
131 struct net_device *pdev = NULL;
132 struct eth_bearer *eb_ptr = ð_bearers[0];
133 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
134 char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;
135
136 /* Find device with specified name */
137
138 for_each_netdev(&init_net, pdev){
139 if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
140 dev = pdev;
141 break;
142 }
143 }
144 if (!dev)
145 return -ENODEV;
146
147 /* Find Ethernet bearer for device (or create one) */
148
149 for (;(eb_ptr != stop) && eb_ptr->dev && (eb_ptr->dev != dev); eb_ptr++);
150 if (eb_ptr == stop)
151 return -EDQUOT;
152 if (!eb_ptr->dev) {
153 eb_ptr->dev = dev;
154 eb_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
155 eb_ptr->tipc_packet_type.dev = dev;
156 eb_ptr->tipc_packet_type.func = recv_msg;
157 eb_ptr->tipc_packet_type.af_packet_priv = eb_ptr;
158 INIT_LIST_HEAD(&(eb_ptr->tipc_packet_type.list));
159 dev_hold(dev);
160 dev_add_pack(&eb_ptr->tipc_packet_type);
161 }
162
163 /* Associate TIPC bearer with Ethernet bearer */
164
165 eb_ptr->bearer = tb_ptr;
166 tb_ptr->usr_handle = (void *)eb_ptr;
167 tb_ptr->mtu = dev->mtu;
168 tb_ptr->blocked = 0;
169 tb_ptr->addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
170 memcpy(&tb_ptr->addr.dev_addr, dev->dev_addr, ETH_ALEN);
171 return 0;
172 }
173
174 /**
175 * disable_bearer - detach TIPC bearer from an Ethernet interface
176 *
177 * We really should do dev_remove_pack() here, but this function can not be
178 * called at tasklet level. => Use eth_bearer->bearer as a flag to throw away
179 * incoming buffers, & postpone dev_remove_pack() to eth_media_stop() on exit.
180 */
181
182 static void disable_bearer(struct tipc_bearer *tb_ptr)
183 {
184 ((struct eth_bearer *)tb_ptr->usr_handle)->bearer = NULL;
185 }
186
187 /**
188 * recv_notification - handle device updates from OS
189 *
190 * Change the state of the Ethernet bearer (if any) associated with the
191 * specified device.
192 */
193
194 static int recv_notification(struct notifier_block *nb, unsigned long evt,
195 void *dv)
196 {
197 struct net_device *dev = (struct net_device *)dv;
198 struct eth_bearer *eb_ptr = ð_bearers[0];
199 struct eth_bearer *stop = ð_bearers[MAX_ETH_BEARERS];
200
201 if (!net_eq(dev_net(dev), &init_net))
202 return NOTIFY_DONE;
203
204 while ((eb_ptr->dev != dev)) {
205 if (++eb_ptr == stop)
206 return NOTIFY_DONE; /* couldn't find device */
207 }
208 if (!eb_ptr->bearer)
209 return NOTIFY_DONE; /* bearer had been disabled */
210
211 eb_ptr->bearer->mtu = dev->mtu;
212
213 switch (evt) {
214 case NETDEV_CHANGE:
215 if (netif_carrier_ok(dev))
216 tipc_continue(eb_ptr->bearer);
217 else
218 tipc_block_bearer(eb_ptr->bearer->name);
219 break;
220 case NETDEV_UP:
221 tipc_continue(eb_ptr->bearer);
222 break;
223 case NETDEV_DOWN:
224 tipc_block_bearer(eb_ptr->bearer->name);
225 break;
226 case NETDEV_CHANGEMTU:
227 case NETDEV_CHANGEADDR:
228 tipc_block_bearer(eb_ptr->bearer->name);
229 tipc_continue(eb_ptr->bearer);
230 break;
231 case NETDEV_UNREGISTER:
232 case NETDEV_CHANGENAME:
233 tipc_disable_bearer(eb_ptr->bearer->name);
234 break;
235 }
236 return NOTIFY_OK;
237 }
238
239 /**
240 * eth_addr2str - convert Ethernet address to string
241 */
242
243 static char *eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
244 {
245 unchar *addr = (unchar *)&a->dev_addr;
246
247 if (str_size < 18)
248 *str_buf = '\0';
249 else
250 sprintf(str_buf, "%pM", addr);
251 return str_buf;
252 }
253
254 /**
255 * tipc_eth_media_start - activate Ethernet bearer support
256 *
257 * Register Ethernet media type with TIPC bearer code. Also register
258 * with OS for notifications about device state changes.
259 */
260
261 int tipc_eth_media_start(void)
262 {
263 struct tipc_media_addr bcast_addr;
264 int res;
265
266 if (eth_started)
267 return -EINVAL;
268
269 bcast_addr.type = htonl(TIPC_MEDIA_TYPE_ETH);
270 memset(&bcast_addr.dev_addr, 0xff, ETH_ALEN);
271
272 memset(eth_bearers, 0, sizeof(eth_bearers));
273
274 res = tipc_register_media(TIPC_MEDIA_TYPE_ETH, "eth",
275 enable_bearer, disable_bearer, send_msg,
276 eth_addr2str, &bcast_addr, ETH_LINK_PRIORITY,
277 ETH_LINK_TOLERANCE, ETH_LINK_WINDOW);
278 if (res)
279 return res;
280
281 notifier.notifier_call = &recv_notification;
282 notifier.priority = 0;
283 res = register_netdevice_notifier(¬ifier);
284 if (!res)
285 eth_started = 1;
286 return res;
287 }
288
289 /**
290 * tipc_eth_media_stop - deactivate Ethernet bearer support
291 */
292
293 void tipc_eth_media_stop(void)
294 {
295 int i;
296
297 if (!eth_started)
298 return;
299
300 unregister_netdevice_notifier(¬ifier);
301 for (i = 0; i < MAX_ETH_BEARERS ; i++) {
302 if (eth_bearers[i].bearer) {
303 eth_bearers[i].bearer->blocked = 1;
304 eth_bearers[i].bearer = NULL;
305 }
306 if (eth_bearers[i].dev) {
307 dev_remove_pack(ð_bearers[i].tipc_packet_type);
308 dev_put(eth_bearers[i].dev);
309 }
310 }
311 memset(ð_bearers, 0, sizeof(eth_bearers));
312 eth_started = 0;
313 }
314
|
This page was automatically generated by the
LXR engine.
|