[NETFILTER]: ebt_mark: add or/and/xor action support to mark target
[linux-2.6.git] / net / bridge / br_if.c
1 /*
2  *      Userspace interface
3  *      Linux ethernet bridge
4  *
5  *      Authors:
6  *      Lennert Buytenhek               <buytenh@gnu.org>
7  *
8  *      $Id: br_if.c,v 1.7 2001/12/24 00:59:55 davem Exp $
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/netdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/if_arp.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/rtnetlink.h>
23 #include <linux/if_ether.h>
24 #include <net/sock.h>
25
26 #include "br_private.h"
27
28 /*
29  * Determine initial path cost based on speed.
30  * using recommendations from 802.1d standard
31  *
32  * Need to simulate user ioctl because not all device's that support
33  * ethtool, use ethtool_ops.  Also, since driver might sleep need to
34  * not be holding any locks.
35  */
36 static int port_cost(struct net_device *dev)
37 {
38         struct ethtool_cmd ecmd = { ETHTOOL_GSET };
39         struct ifreq ifr;
40         mm_segment_t old_fs;
41         int err;
42
43         strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
44         ifr.ifr_data = (void __user *) &ecmd;
45
46         old_fs = get_fs();
47         set_fs(KERNEL_DS);
48         err = dev_ethtool(&ifr);
49         set_fs(old_fs);
50         
51         if (!err) {
52                 switch(ecmd.speed) {
53                 case SPEED_100:
54                         return 19;
55                 case SPEED_1000:
56                         return 4;
57                 case SPEED_10000:
58                         return 2;
59                 case SPEED_10:
60                         return 100;
61                 }
62         }
63
64         /* Old silly heuristics based on name */
65         if (!strncmp(dev->name, "lec", 3))
66                 return 7;
67
68         if (!strncmp(dev->name, "plip", 4))
69                 return 2500;
70
71         return 100;     /* assume old 10Mbps */
72 }
73
74
75 /*
76  * Check for port carrier transistions.
77  * Called from work queue to allow for calling functions that
78  * might sleep (such as speed check), and to debounce.
79  */
80 static void port_carrier_check(void *arg)
81 {
82         struct net_device *dev = arg;
83         struct net_bridge_port *p;
84         struct net_bridge *br;
85
86         rtnl_lock();
87         p = dev->br_port;
88         if (!p)
89                 goto done;
90         br = p->br;
91
92         if (netif_carrier_ok(dev))
93                 p->path_cost = port_cost(dev);
94
95         if (br->dev->flags & IFF_UP) {
96                 spin_lock_bh(&br->lock);
97                 if (netif_carrier_ok(dev)) {
98                         if (p->state == BR_STATE_DISABLED)
99                                 br_stp_enable_port(p);
100                 } else {
101                         if (p->state != BR_STATE_DISABLED)
102                                 br_stp_disable_port(p);
103                 }
104                 spin_unlock_bh(&br->lock);
105         }
106 done:
107         rtnl_unlock();
108 }
109
110 static void release_nbp(struct kobject *kobj)
111 {
112         struct net_bridge_port *p
113                 = container_of(kobj, struct net_bridge_port, kobj);
114         kfree(p);
115 }
116
117 static struct kobj_type brport_ktype = {
118 #ifdef CONFIG_SYSFS
119         .sysfs_ops = &brport_sysfs_ops,
120 #endif
121         .release = release_nbp,
122 };
123
124 static void destroy_nbp(struct net_bridge_port *p)
125 {
126         struct net_device *dev = p->dev;
127
128         p->br = NULL;
129         p->dev = NULL;
130         dev_put(dev);
131
132         kobject_put(&p->kobj);
133 }
134
135 static void destroy_nbp_rcu(struct rcu_head *head)
136 {
137         struct net_bridge_port *p =
138                         container_of(head, struct net_bridge_port, rcu);
139         destroy_nbp(p);
140 }
141
142 /* Delete port(interface) from bridge is done in two steps.
143  * via RCU. First step, marks device as down. That deletes
144  * all the timers and stops new packets from flowing through.
145  *
146  * Final cleanup doesn't occur until after all CPU's finished
147  * processing packets.
148  *
149  * Protected from multiple admin operations by RTNL mutex
150  */
151 static void del_nbp(struct net_bridge_port *p)
152 {
153         struct net_bridge *br = p->br;
154         struct net_device *dev = p->dev;
155
156         sysfs_remove_link(&br->ifobj, dev->name);
157
158         dev_set_promiscuity(dev, -1);
159
160         cancel_delayed_work(&p->carrier_check);
161
162         spin_lock_bh(&br->lock);
163         br_stp_disable_port(p);
164         spin_unlock_bh(&br->lock);
165
166         br_fdb_delete_by_port(br, p);
167
168         list_del_rcu(&p->list);
169
170         rcu_assign_pointer(dev->br_port, NULL);
171
172         kobject_uevent(&p->kobj, KOBJ_REMOVE);
173         kobject_del(&p->kobj);
174
175         call_rcu(&p->rcu, destroy_nbp_rcu);
176 }
177
178 /* called with RTNL */
179 static void del_br(struct net_bridge *br)
180 {
181         struct net_bridge_port *p, *n;
182
183         list_for_each_entry_safe(p, n, &br->port_list, list) {
184                 del_nbp(p);
185         }
186
187         del_timer_sync(&br->gc_timer);
188
189         br_sysfs_delbr(br->dev);
190         unregister_netdevice(br->dev);
191 }
192
193 static struct net_device *new_bridge_dev(const char *name)
194 {
195         struct net_bridge *br;
196         struct net_device *dev;
197
198         dev = alloc_netdev(sizeof(struct net_bridge), name,
199                            br_dev_setup);
200         
201         if (!dev)
202                 return NULL;
203
204         br = netdev_priv(dev);
205         br->dev = dev;
206
207         spin_lock_init(&br->lock);
208         INIT_LIST_HEAD(&br->port_list);
209         spin_lock_init(&br->hash_lock);
210
211         br->bridge_id.prio[0] = 0x80;
212         br->bridge_id.prio[1] = 0x00;
213
214         memcpy(br->group_addr, br_group_address, ETH_ALEN);
215
216         br->feature_mask = dev->features;
217         br->stp_enabled = 0;
218         br->designated_root = br->bridge_id;
219         br->root_path_cost = 0;
220         br->root_port = 0;
221         br->bridge_max_age = br->max_age = 20 * HZ;
222         br->bridge_hello_time = br->hello_time = 2 * HZ;
223         br->bridge_forward_delay = br->forward_delay = 15 * HZ;
224         br->topology_change = 0;
225         br->topology_change_detected = 0;
226         br->ageing_time = 300 * HZ;
227         INIT_LIST_HEAD(&br->age_list);
228
229         br_stp_timer_init(br);
230
231         return dev;
232 }
233
234 /* find an available port number */
235 static int find_portno(struct net_bridge *br)
236 {
237         int index;
238         struct net_bridge_port *p;
239         unsigned long *inuse;
240
241         inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
242                         GFP_KERNEL);
243         if (!inuse)
244                 return -ENOMEM;
245
246         set_bit(0, inuse);      /* zero is reserved */
247         list_for_each_entry(p, &br->port_list, list) {
248                 set_bit(p->port_no, inuse);
249         }
250         index = find_first_zero_bit(inuse, BR_MAX_PORTS);
251         kfree(inuse);
252
253         return (index >= BR_MAX_PORTS) ? -EXFULL : index;
254 }
255
256 /* called with RTNL but without bridge lock */
257 static struct net_bridge_port *new_nbp(struct net_bridge *br, 
258                                        struct net_device *dev)
259 {
260         int index;
261         struct net_bridge_port *p;
262         
263         index = find_portno(br);
264         if (index < 0)
265                 return ERR_PTR(index);
266
267         p = kzalloc(sizeof(*p), GFP_KERNEL);
268         if (p == NULL)
269                 return ERR_PTR(-ENOMEM);
270
271         p->br = br;
272         dev_hold(dev);
273         p->dev = dev;
274         p->path_cost = port_cost(dev);
275         p->priority = 0x8000 >> BR_PORT_BITS;
276         p->port_no = index;
277         br_init_port(p);
278         p->state = BR_STATE_DISABLED;
279         INIT_WORK(&p->carrier_check, port_carrier_check, dev);
280         br_stp_port_timer_init(p);
281
282         kobject_init(&p->kobj);
283         kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
284         p->kobj.ktype = &brport_ktype;
285         p->kobj.parent = &(dev->class_dev.kobj);
286         p->kobj.kset = NULL;
287
288         return p;
289 }
290
291 int br_add_bridge(const char *name)
292 {
293         struct net_device *dev;
294         int ret;
295
296         dev = new_bridge_dev(name);
297         if (!dev) 
298                 return -ENOMEM;
299
300         rtnl_lock();
301         if (strchr(dev->name, '%')) {
302                 ret = dev_alloc_name(dev, dev->name);
303                 if (ret < 0) {
304                         free_netdev(dev);
305                         goto out;
306                 }
307         }
308
309         ret = register_netdevice(dev);
310         if (ret)
311                 goto out;
312
313         ret = br_sysfs_addbr(dev);
314         if (ret)
315                 unregister_netdevice(dev);
316  out:
317         rtnl_unlock();
318         return ret;
319 }
320
321 int br_del_bridge(const char *name)
322 {
323         struct net_device *dev;
324         int ret = 0;
325
326         rtnl_lock();
327         dev = __dev_get_by_name(name);
328         if (dev == NULL) 
329                 ret =  -ENXIO;  /* Could not find device */
330
331         else if (!(dev->priv_flags & IFF_EBRIDGE)) {
332                 /* Attempt to delete non bridge device! */
333                 ret = -EPERM;
334         }
335
336         else if (dev->flags & IFF_UP) {
337                 /* Not shutdown yet. */
338                 ret = -EBUSY;
339         } 
340
341         else 
342                 del_br(netdev_priv(dev));
343
344         rtnl_unlock();
345         return ret;
346 }
347
348 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
349 int br_min_mtu(const struct net_bridge *br)
350 {
351         const struct net_bridge_port *p;
352         int mtu = 0;
353
354         ASSERT_RTNL();
355
356         if (list_empty(&br->port_list))
357                 mtu = ETH_DATA_LEN;
358         else {
359                 list_for_each_entry(p, &br->port_list, list) {
360                         if (!mtu  || p->dev->mtu < mtu)
361                                 mtu = p->dev->mtu;
362                 }
363         }
364         return mtu;
365 }
366
367 /*
368  * Recomputes features using slave's features
369  */
370 void br_features_recompute(struct net_bridge *br)
371 {
372         struct net_bridge_port *p;
373         unsigned long features, checksum;
374
375         checksum = br->feature_mask & NETIF_F_ALL_CSUM ? NETIF_F_NO_CSUM : 0;
376         features = br->feature_mask & ~NETIF_F_ALL_CSUM;
377
378         list_for_each_entry(p, &br->port_list, list) {
379                 unsigned long feature = p->dev->features;
380
381                 if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM))
382                         checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;
383                 if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM))
384                         checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM;
385                 if (!(feature & NETIF_F_IP_CSUM))
386                         checksum = 0;
387
388                 if (feature & NETIF_F_GSO)
389                         feature |= NETIF_F_GSO_SOFTWARE;
390                 feature |= NETIF_F_GSO;
391
392                 features &= feature;
393         }
394
395         if (!(checksum & NETIF_F_ALL_CSUM))
396                 features &= ~NETIF_F_SG;
397         if (!(features & NETIF_F_SG))
398                 features &= ~NETIF_F_GSO_MASK;
399
400         br->dev->features = features | checksum | NETIF_F_LLTX |
401                             NETIF_F_GSO_ROBUST;
402 }
403
404 /* called with RTNL */
405 int br_add_if(struct net_bridge *br, struct net_device *dev)
406 {
407         struct net_bridge_port *p;
408         int err = 0;
409
410         if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
411                 return -EINVAL;
412
413         if (dev->hard_start_xmit == br_dev_xmit)
414                 return -ELOOP;
415
416         if (dev->br_port != NULL)
417                 return -EBUSY;
418
419         p = new_nbp(br, dev);
420         if (IS_ERR(p))
421                 return PTR_ERR(p);
422
423         err = kobject_add(&p->kobj);
424         if (err)
425                 goto err0;
426
427         err = br_fdb_insert(br, p, dev->dev_addr);
428         if (err)
429                 goto err1;
430
431         err = br_sysfs_addif(p);
432         if (err)
433                 goto err2;
434
435         rcu_assign_pointer(dev->br_port, p);
436         dev_set_promiscuity(dev, 1);
437
438         list_add_rcu(&p->list, &br->port_list);
439
440         spin_lock_bh(&br->lock);
441         br_stp_recalculate_bridge_id(br);
442         br_features_recompute(br);
443         schedule_delayed_work(&p->carrier_check, BR_PORT_DEBOUNCE);
444         spin_unlock_bh(&br->lock);
445
446         dev_set_mtu(br->dev, br_min_mtu(br));
447         kobject_uevent(&p->kobj, KOBJ_ADD);
448
449         return 0;
450 err2:
451         br_fdb_delete_by_port(br, p);
452 err1:
453         kobject_del(&p->kobj);
454 err0:
455         kobject_put(&p->kobj);
456         return err;
457 }
458
459 /* called with RTNL */
460 int br_del_if(struct net_bridge *br, struct net_device *dev)
461 {
462         struct net_bridge_port *p = dev->br_port;
463         
464         if (!p || p->br != br) 
465                 return -EINVAL;
466
467         del_nbp(p);
468
469         spin_lock_bh(&br->lock);
470         br_stp_recalculate_bridge_id(br);
471         br_features_recompute(br);
472         spin_unlock_bh(&br->lock);
473
474         return 0;
475 }
476
477 void __exit br_cleanup_bridges(void)
478 {
479         struct net_device *dev, *nxt;
480
481         rtnl_lock();
482         for (dev = dev_base; dev; dev = nxt) {
483                 nxt = dev->next;
484                 if (dev->priv_flags & IFF_EBRIDGE)
485                         del_br(dev->priv);
486         }
487         rtnl_unlock();
488
489 }