ea9438fc6855fb3a569e7e25a2064d5191a14989
[linux-2.6.git] / net / atm / br2684.c
1 /*
2  * Ethernet netdevice using ATM AAL5 as underlying carrier
3  * (RFC1483 obsoleted by RFC2684) for Linux
4  *
5  * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
6  *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
7  */
8
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/list.h>
13 #include <linux/netdevice.h>
14 #include <linux/skbuff.h>
15 #include <linux/etherdevice.h>
16 #include <linux/rtnetlink.h>
17 #include <linux/ip.h>
18 #include <asm/uaccess.h>
19 #include <net/arp.h>
20 #include <linux/atm.h>
21 #include <linux/atmdev.h>
22 #include <linux/capability.h>
23 #include <linux/seq_file.h>
24
25 #include <linux/atmbr2684.h>
26
27 #include "common.h"
28
29 #ifdef SKB_DEBUG
30 static void skb_debug(const struct sk_buff *skb)
31 {
32 #define NUM2PRINT 50
33         char buf[NUM2PRINT * 3 + 1];    /* 3 chars per byte */
34         int i = 0;
35         for (i = 0; i < skb->len && i < NUM2PRINT; i++) {
36                 sprintf(buf + i * 3, "%2.2x ", 0xff & skb->data[i]);
37         }
38         printk(KERN_DEBUG "br2684: skb: %s\n", buf);
39 }
40 #else
41 #define skb_debug(skb)  do {} while (0)
42 #endif
43
44 #define BR2684_ETHERTYPE_LEN    2
45 #define BR2684_PAD_LEN          2
46
47 #define LLC             0xaa, 0xaa, 0x03
48 #define SNAP_BRIDGED    0x00, 0x80, 0xc2
49 #define SNAP_ROUTED     0x00, 0x00, 0x00
50 #define PID_ETHERNET    0x00, 0x07
51 #define ETHERTYPE_IPV4  0x08, 0x00
52 #define ETHERTYPE_IPV6  0x86, 0xdd
53 #define PAD_BRIDGED     0x00, 0x00
54
55 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
56 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
57 static const unsigned char llc_oui_pid_pad[] =
58                         { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
59 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
60 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
61
62 enum br2684_encaps {
63         e_vc = BR2684_ENCAPS_VC,
64         e_llc = BR2684_ENCAPS_LLC,
65 };
66
67 struct br2684_vcc {
68         struct atm_vcc *atmvcc;
69         struct net_device *device;
70         /* keep old push, pop functions for chaining */
71         void (*old_push) (struct atm_vcc * vcc, struct sk_buff * skb);
72         /* void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb); */
73         enum br2684_encaps encaps;
74         struct list_head brvccs;
75 #ifdef CONFIG_ATM_BR2684_IPFILTER
76         struct br2684_filter filter;
77 #endif /* CONFIG_ATM_BR2684_IPFILTER */
78         unsigned copies_needed, copies_failed;
79 };
80
81 struct br2684_dev {
82         struct net_device *net_dev;
83         struct list_head br2684_devs;
84         int number;
85         struct list_head brvccs;        /* one device <=> one vcc (before xmas) */
86         struct net_device_stats stats;
87         int mac_was_set;
88         enum br2684_payload payload;
89 };
90
91 /*
92  * This lock should be held for writing any time the list of devices or
93  * their attached vcc's could be altered.  It should be held for reading
94  * any time these are being queried.  Note that we sometimes need to
95  * do read-locking under interrupt context, so write locking must block
96  * the current CPU's interrupts
97  */
98 static DEFINE_RWLOCK(devs_lock);
99
100 static LIST_HEAD(br2684_devs);
101
102 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
103 {
104         return (struct br2684_dev *)netdev_priv(net_dev);
105 }
106
107 static inline struct net_device *list_entry_brdev(const struct list_head *le)
108 {
109         return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
110 }
111
112 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
113 {
114         return (struct br2684_vcc *)(atmvcc->user_back);
115 }
116
117 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
118 {
119         return list_entry(le, struct br2684_vcc, brvccs);
120 }
121
122 /* Caller should hold read_lock(&devs_lock) */
123 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
124 {
125         struct list_head *lh;
126         struct net_device *net_dev;
127         switch (s->method) {
128         case BR2684_FIND_BYNUM:
129                 list_for_each(lh, &br2684_devs) {
130                         net_dev = list_entry_brdev(lh);
131                         if (BRPRIV(net_dev)->number == s->spec.devnum)
132                                 return net_dev;
133                 }
134                 break;
135         case BR2684_FIND_BYIFNAME:
136                 list_for_each(lh, &br2684_devs) {
137                         net_dev = list_entry_brdev(lh);
138                         if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
139                                 return net_dev;
140                 }
141                 break;
142         }
143         return NULL;
144 }
145
146 /*
147  * Send a packet out a particular vcc.  Not to useful right now, but paves
148  * the way for multiple vcc's per itf.  Returns true if we can send,
149  * otherwise false
150  */
151 static int br2684_xmit_vcc(struct sk_buff *skb, struct br2684_dev *brdev,
152                            struct br2684_vcc *brvcc)
153 {
154         struct atm_vcc *atmvcc;
155         int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
156
157         if (skb_headroom(skb) < minheadroom) {
158                 struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
159                 brvcc->copies_needed++;
160                 dev_kfree_skb(skb);
161                 if (skb2 == NULL) {
162                         brvcc->copies_failed++;
163                         return 0;
164                 }
165                 skb = skb2;
166         }
167
168         if (brvcc->encaps == e_llc) {
169                 if (brdev->payload == p_bridged) {
170                         skb_push(skb, sizeof(llc_oui_pid_pad));
171                         skb_copy_to_linear_data(skb, llc_oui_pid_pad,
172                                                 sizeof(llc_oui_pid_pad));
173                 } else if (brdev->payload == p_routed) {
174                         unsigned short prot = ntohs(skb->protocol);
175
176                         skb_push(skb, sizeof(llc_oui_ipv4));
177                         switch (prot) {
178                         case ETH_P_IP:
179                                 skb_copy_to_linear_data(skb, llc_oui_ipv4,
180                                                         sizeof(llc_oui_ipv4));
181                                 break;
182                         case ETH_P_IPV6:
183                                 skb_copy_to_linear_data(skb, llc_oui_ipv6,
184                                                         sizeof(llc_oui_ipv6));
185                                 break;
186                         default:
187                                 dev_kfree_skb(skb);
188                                 return 0;
189                         }
190                 }
191         } else { /* e_vc */
192                 if (brdev->payload == p_bridged) {
193                         skb_push(skb, 2);
194                         memset(skb->data, 0, 2);
195                 } else { /* p_routed */
196                         skb_pull(skb, ETH_HLEN);
197                 }
198         }
199         skb_debug(skb);
200
201         ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
202         pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
203         if (!atm_may_send(atmvcc, skb->truesize)) {
204                 /*
205                  * We free this here for now, because we cannot know in a higher
206                  * layer whether the skb pointer it supplied wasn't freed yet.
207                  * Now, it always is.
208                  */
209                 dev_kfree_skb(skb);
210                 return 0;
211         }
212         atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
213         ATM_SKB(skb)->atm_options = atmvcc->atm_options;
214         brdev->stats.tx_packets++;
215         brdev->stats.tx_bytes += skb->len;
216         atmvcc->send(atmvcc, skb);
217         return 1;
218 }
219
220 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
221                                                    const struct br2684_dev *brdev)
222 {
223         return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);        /* 1 vcc/dev right now */
224 }
225
226 static int br2684_start_xmit(struct sk_buff *skb, struct net_device *dev)
227 {
228         struct br2684_dev *brdev = BRPRIV(dev);
229         struct br2684_vcc *brvcc;
230
231         pr_debug("br2684_start_xmit, skb->dst=%p\n", skb->dst);
232         read_lock(&devs_lock);
233         brvcc = pick_outgoing_vcc(skb, brdev);
234         if (brvcc == NULL) {
235                 pr_debug("no vcc attached to dev %s\n", dev->name);
236                 brdev->stats.tx_errors++;
237                 brdev->stats.tx_carrier_errors++;
238                 /* netif_stop_queue(dev); */
239                 dev_kfree_skb(skb);
240                 read_unlock(&devs_lock);
241                 return 0;
242         }
243         if (!br2684_xmit_vcc(skb, brdev, brvcc)) {
244                 /*
245                  * We should probably use netif_*_queue() here, but that
246                  * involves added complication.  We need to walk before
247                  * we can run.
248                  *
249                  * Don't free here! this pointer might be no longer valid!
250                  */
251                 brdev->stats.tx_errors++;
252                 brdev->stats.tx_fifo_errors++;
253         }
254         read_unlock(&devs_lock);
255         return 0;
256 }
257
258 static struct net_device_stats *br2684_get_stats(struct net_device *dev)
259 {
260         pr_debug("br2684_get_stats\n");
261         return &BRPRIV(dev)->stats;
262 }
263
264 /*
265  * We remember when the MAC gets set, so we don't override it later with
266  * the ESI of the ATM card of the first VC
267  */
268 static int (*my_eth_mac_addr) (struct net_device *, void *);
269 static int br2684_mac_addr(struct net_device *dev, void *p)
270 {
271         int err = my_eth_mac_addr(dev, p);
272         if (!err)
273                 BRPRIV(dev)->mac_was_set = 1;
274         return err;
275 }
276
277 #ifdef CONFIG_ATM_BR2684_IPFILTER
278 /* this IOCTL is experimental. */
279 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
280 {
281         struct br2684_vcc *brvcc;
282         struct br2684_filter_set fs;
283
284         if (copy_from_user(&fs, arg, sizeof fs))
285                 return -EFAULT;
286         if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
287                 /*
288                  * This is really a per-vcc thing, but we can also search
289                  * by device.
290                  */
291                 struct br2684_dev *brdev;
292                 read_lock(&devs_lock);
293                 brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
294                 if (brdev == NULL || list_empty(&brdev->brvccs) || brdev->brvccs.next != brdev->brvccs.prev)    /* >1 VCC */
295                         brvcc = NULL;
296                 else
297                         brvcc = list_entry_brvcc(brdev->brvccs.next);
298                 read_unlock(&devs_lock);
299                 if (brvcc == NULL)
300                         return -ESRCH;
301         } else
302                 brvcc = BR2684_VCC(atmvcc);
303         memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
304         return 0;
305 }
306
307 /* Returns 1 if packet should be dropped */
308 static inline int
309 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
310 {
311         if (brvcc->filter.netmask == 0)
312                 return 0;       /* no filter in place */
313         if (type == htons(ETH_P_IP) &&
314             (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
315              netmask) == brvcc->filter.prefix)
316                 return 0;
317         if (type == htons(ETH_P_ARP))
318                 return 0;
319         /*
320          * TODO: we should probably filter ARPs too.. don't want to have
321          * them returning values that don't make sense, or is that ok?
322          */
323         return 1;               /* drop */
324 }
325 #endif /* CONFIG_ATM_BR2684_IPFILTER */
326
327 static void br2684_close_vcc(struct br2684_vcc *brvcc)
328 {
329         pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
330         write_lock_irq(&devs_lock);
331         list_del(&brvcc->brvccs);
332         write_unlock_irq(&devs_lock);
333         brvcc->atmvcc->user_back = NULL;        /* what about vcc->recvq ??? */
334         brvcc->old_push(brvcc->atmvcc, NULL);   /* pass on the bad news */
335         kfree(brvcc);
336         module_put(THIS_MODULE);
337 }
338
339 /* when AAL5 PDU comes in: */
340 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
341 {
342         struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
343         struct net_device *net_dev = brvcc->device;
344         struct br2684_dev *brdev = BRPRIV(net_dev);
345
346         pr_debug("br2684_push\n");
347
348         if (unlikely(skb == NULL)) {
349                 /* skb==NULL means VCC is being destroyed */
350                 br2684_close_vcc(brvcc);
351                 if (list_empty(&brdev->brvccs)) {
352                         write_lock_irq(&devs_lock);
353                         list_del(&brdev->br2684_devs);
354                         write_unlock_irq(&devs_lock);
355                         unregister_netdev(net_dev);
356                         free_netdev(net_dev);
357                 }
358                 return;
359         }
360
361         skb_debug(skb);
362         atm_return(atmvcc, skb->truesize);
363         pr_debug("skb from brdev %p\n", brdev);
364         if (brvcc->encaps == e_llc) {
365
366                 if (skb->len > 7 && skb->data[7] == 0x01)
367                         __skb_trim(skb, skb->len - 4);
368
369                 /* accept packets that have "ipv[46]" in the snap header */
370                 if ((skb->len >= (sizeof(llc_oui_ipv4)))
371                     &&
372                     (memcmp
373                      (skb->data, llc_oui_ipv4,
374                       sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
375                         if (memcmp
376                             (skb->data + 6, ethertype_ipv6,
377                              sizeof(ethertype_ipv6)) == 0)
378                                 skb->protocol = htons(ETH_P_IPV6);
379                         else if (memcmp
380                                  (skb->data + 6, ethertype_ipv4,
381                                   sizeof(ethertype_ipv4)) == 0)
382                                 skb->protocol = htons(ETH_P_IP);
383                         else
384                                 goto error;
385                         skb_pull(skb, sizeof(llc_oui_ipv4));
386                         skb_reset_network_header(skb);
387                         skb->pkt_type = PACKET_HOST;
388                         /*
389                          * Let us waste some time for checking the encapsulation.
390                          * Note, that only 7 char is checked so frames with a valid FCS
391                          * are also accepted (but FCS is not checked of course).
392                          */
393                 } else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
394                            (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
395                         skb_pull(skb, sizeof(llc_oui_pid_pad));
396                         skb->protocol = eth_type_trans(skb, net_dev);
397                 } else
398                         goto error;
399
400         } else { /* e_vc */
401                 if (brdev->payload == p_routed) {
402                         struct iphdr *iph;
403
404                         skb_reset_network_header(skb);
405                         iph = ip_hdr(skb);
406                         if (iph->version == 4)
407                                 skb->protocol = htons(ETH_P_IP);
408                         else if (iph->version == 6)
409                                 skb->protocol = htons(ETH_P_IPV6);
410                         else
411                                 goto error;
412                         skb->pkt_type = PACKET_HOST;
413                 } else { /* p_bridged */
414                         /* first 2 chars should be 0 */
415                         if (*((u16 *) (skb->data)) != 0)
416                                 goto error;
417                         skb_pull(skb, BR2684_PAD_LEN);
418                         skb->protocol = eth_type_trans(skb, net_dev);
419                 }
420         }
421
422 #ifdef CONFIG_ATM_BR2684_IPFILTER
423         if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
424                 goto dropped;
425 #endif /* CONFIG_ATM_BR2684_IPFILTER */
426         skb->dev = net_dev;
427         ATM_SKB(skb)->vcc = atmvcc;     /* needed ? */
428         pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
429         skb_debug(skb);
430         /* sigh, interface is down? */
431         if (unlikely(!(net_dev->flags & IFF_UP)))
432                 goto dropped;
433         brdev->stats.rx_packets++;
434         brdev->stats.rx_bytes += skb->len;
435         memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
436         netif_rx(skb);
437         return;
438
439 dropped:
440         brdev->stats.rx_dropped++;
441         goto free_skb;
442 error:
443         brdev->stats.rx_errors++;
444 free_skb:
445         dev_kfree_skb(skb);
446         return;
447 }
448
449 /*
450  * Assign a vcc to a dev
451  * Note: we do not have explicit unassign, but look at _push()
452  */
453 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
454 {
455         int err;
456         struct br2684_vcc *brvcc;
457         struct sk_buff *skb;
458         struct sk_buff_head *rq;
459         struct br2684_dev *brdev;
460         struct net_device *net_dev;
461         struct atm_backend_br2684 be;
462         unsigned long flags;
463
464         if (copy_from_user(&be, arg, sizeof be))
465                 return -EFAULT;
466         brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
467         if (!brvcc)
468                 return -ENOMEM;
469         write_lock_irq(&devs_lock);
470         net_dev = br2684_find_dev(&be.ifspec);
471         if (net_dev == NULL) {
472                 printk(KERN_ERR
473                        "br2684: tried to attach to non-existant device\n");
474                 err = -ENXIO;
475                 goto error;
476         }
477         brdev = BRPRIV(net_dev);
478         if (atmvcc->push == NULL) {
479                 err = -EBADFD;
480                 goto error;
481         }
482         if (!list_empty(&brdev->brvccs)) {
483                 /* Only 1 VCC/dev right now */
484                 err = -EEXIST;
485                 goto error;
486         }
487         if (be.fcs_in != BR2684_FCSIN_NO || be.fcs_out != BR2684_FCSOUT_NO ||
488             be.fcs_auto || be.has_vpiid || be.send_padding || (be.encaps !=
489                                                                BR2684_ENCAPS_VC
490                                                                && be.encaps !=
491                                                                BR2684_ENCAPS_LLC)
492             || be.min_size != 0) {
493                 err = -EINVAL;
494                 goto error;
495         }
496         pr_debug("br2684_regvcc vcc=%p, encaps=%d, brvcc=%p\n", atmvcc,
497                  be.encaps, brvcc);
498         if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
499                 unsigned char *esi = atmvcc->dev->esi;
500                 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
501                         memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
502                 else
503                         net_dev->dev_addr[2] = 1;
504         }
505         list_add(&brvcc->brvccs, &brdev->brvccs);
506         write_unlock_irq(&devs_lock);
507         brvcc->device = net_dev;
508         brvcc->atmvcc = atmvcc;
509         atmvcc->user_back = brvcc;
510         brvcc->encaps = (enum br2684_encaps)be.encaps;
511         brvcc->old_push = atmvcc->push;
512         barrier();
513         atmvcc->push = br2684_push;
514
515         rq = &sk_atm(atmvcc)->sk_receive_queue;
516
517         spin_lock_irqsave(&rq->lock, flags);
518         if (skb_queue_empty(rq)) {
519                 skb = NULL;
520         } else {
521                 /* NULL terminate the list.  */
522                 rq->prev->next = NULL;
523                 skb = rq->next;
524         }
525         rq->prev = rq->next = (struct sk_buff *)rq;
526         rq->qlen = 0;
527         spin_unlock_irqrestore(&rq->lock, flags);
528
529         while (skb) {
530                 struct sk_buff *next = skb->next;
531
532                 skb->next = skb->prev = NULL;
533                 br2684_push(atmvcc, skb);
534                 BRPRIV(skb->dev)->stats.rx_bytes -= skb->len;
535                 BRPRIV(skb->dev)->stats.rx_packets--;
536
537                 skb = next;
538         }
539         __module_get(THIS_MODULE);
540         return 0;
541       error:
542         write_unlock_irq(&devs_lock);
543         kfree(brvcc);
544         return err;
545 }
546
547 static void br2684_setup(struct net_device *netdev)
548 {
549         struct br2684_dev *brdev = BRPRIV(netdev);
550
551         ether_setup(netdev);
552         brdev->net_dev = netdev;
553
554         my_eth_mac_addr = netdev->set_mac_address;
555         netdev->set_mac_address = br2684_mac_addr;
556         netdev->hard_start_xmit = br2684_start_xmit;
557         netdev->get_stats = br2684_get_stats;
558
559         INIT_LIST_HEAD(&brdev->brvccs);
560 }
561
562 static void br2684_setup_routed(struct net_device *netdev)
563 {
564         struct br2684_dev *brdev = BRPRIV(netdev);
565         brdev->net_dev = netdev;
566
567         netdev->hard_header_len = 0;
568         my_eth_mac_addr = netdev->set_mac_address;
569         netdev->set_mac_address = br2684_mac_addr;
570         netdev->hard_start_xmit = br2684_start_xmit;
571         netdev->get_stats = br2684_get_stats;
572         netdev->addr_len = 0;
573         netdev->mtu = 1500;
574         netdev->type = ARPHRD_PPP;
575         netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
576         netdev->tx_queue_len = 100;
577         INIT_LIST_HEAD(&brdev->brvccs);
578 }
579
580 static int br2684_create(void __user * arg)
581 {
582         int err;
583         struct net_device *netdev;
584         struct br2684_dev *brdev;
585         struct atm_newif_br2684 ni;
586         enum br2684_payload payload;
587
588         pr_debug("br2684_create\n");
589
590         if (copy_from_user(&ni, arg, sizeof ni)) {
591                 return -EFAULT;
592         }
593
594         if (ni.media & BR2684_FLAG_ROUTED)
595                 payload = p_routed;
596         else
597                 payload = p_bridged;
598         ni.media &= 0xffff;     /* strip flags */
599
600         if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500) {
601                 return -EINVAL;
602         }
603
604         netdev = alloc_netdev(sizeof(struct br2684_dev),
605                               ni.ifname[0] ? ni.ifname : "nas%d",
606                               (payload == p_routed) ?
607                               br2684_setup_routed : br2684_setup);
608         if (!netdev)
609                 return -ENOMEM;
610
611         brdev = BRPRIV(netdev);
612
613         pr_debug("registered netdev %s\n", netdev->name);
614         /* open, stop, do_ioctl ? */
615         err = register_netdev(netdev);
616         if (err < 0) {
617                 printk(KERN_ERR "br2684_create: register_netdev failed\n");
618                 free_netdev(netdev);
619                 return err;
620         }
621
622         write_lock_irq(&devs_lock);
623         brdev->payload = payload;
624         brdev->number = list_empty(&br2684_devs) ? 1 :
625             BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
626         list_add_tail(&brdev->br2684_devs, &br2684_devs);
627         write_unlock_irq(&devs_lock);
628         return 0;
629 }
630
631 /*
632  * This handles ioctls actually performed on our vcc - we must return
633  * -ENOIOCTLCMD for any unrecognized ioctl
634  */
635 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
636                         unsigned long arg)
637 {
638         struct atm_vcc *atmvcc = ATM_SD(sock);
639         void __user *argp = (void __user *)arg;
640         atm_backend_t b;
641
642         int err;
643         switch (cmd) {
644         case ATM_SETBACKEND:
645         case ATM_NEWBACKENDIF:
646                 err = get_user(b, (atm_backend_t __user *) argp);
647                 if (err)
648                         return -EFAULT;
649                 if (b != ATM_BACKEND_BR2684)
650                         return -ENOIOCTLCMD;
651                 if (!capable(CAP_NET_ADMIN))
652                         return -EPERM;
653                 if (cmd == ATM_SETBACKEND)
654                         return br2684_regvcc(atmvcc, argp);
655                 else
656                         return br2684_create(argp);
657 #ifdef CONFIG_ATM_BR2684_IPFILTER
658         case BR2684_SETFILT:
659                 if (atmvcc->push != br2684_push)
660                         return -ENOIOCTLCMD;
661                 if (!capable(CAP_NET_ADMIN))
662                         return -EPERM;
663                 err = br2684_setfilt(atmvcc, argp);
664
665                 return err;
666 #endif /* CONFIG_ATM_BR2684_IPFILTER */
667         }
668         return -ENOIOCTLCMD;
669 }
670
671 static struct atm_ioctl br2684_ioctl_ops = {
672         .owner = THIS_MODULE,
673         .ioctl = br2684_ioctl,
674 };
675
676 #ifdef CONFIG_PROC_FS
677 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
678         __acquires(devs_lock)
679 {
680         read_lock(&devs_lock);
681         return seq_list_start(&br2684_devs, *pos);
682 }
683
684 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
685 {
686         return seq_list_next(v, &br2684_devs, pos);
687 }
688
689 static void br2684_seq_stop(struct seq_file *seq, void *v)
690         __releases(devs_lock)
691 {
692         read_unlock(&devs_lock);
693 }
694
695 static int br2684_seq_show(struct seq_file *seq, void *v)
696 {
697         const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
698                                                     br2684_devs);
699         const struct net_device *net_dev = brdev->net_dev;
700         const struct br2684_vcc *brvcc;
701
702         seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
703                    net_dev->name,
704                    brdev->number,
705                    net_dev->dev_addr,
706                    brdev->mac_was_set ? "set" : "auto");
707
708         list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
709                 seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
710                            ", failed copies %u/%u"
711                            "\n", brvcc->atmvcc->dev->number,
712                            brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
713                            (brvcc->encaps == e_llc) ? "LLC" : "VC",
714                            (brdev->payload == p_bridged) ? "bridged" : "routed",
715                            brvcc->copies_failed, brvcc->copies_needed);
716 #ifdef CONFIG_ATM_BR2684_IPFILTER
717 #define b1(var, byte)   ((u8 *) &brvcc->filter.var)[byte]
718 #define bs(var)         b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
719                 if (brvcc->filter.netmask != 0)
720                         seq_printf(seq, "    filter=%d.%d.%d.%d/"
721                                    "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
722 #undef bs
723 #undef b1
724 #endif /* CONFIG_ATM_BR2684_IPFILTER */
725         }
726         return 0;
727 }
728
729 static const struct seq_operations br2684_seq_ops = {
730         .start = br2684_seq_start,
731         .next = br2684_seq_next,
732         .stop = br2684_seq_stop,
733         .show = br2684_seq_show,
734 };
735
736 static int br2684_proc_open(struct inode *inode, struct file *file)
737 {
738         return seq_open(file, &br2684_seq_ops);
739 }
740
741 static const struct file_operations br2684_proc_ops = {
742         .owner = THIS_MODULE,
743         .open = br2684_proc_open,
744         .read = seq_read,
745         .llseek = seq_lseek,
746         .release = seq_release,
747 };
748
749 extern struct proc_dir_entry *atm_proc_root;    /* from proc.c */
750 #endif /* CONFIG_PROC_FS */
751
752 static int __init br2684_init(void)
753 {
754 #ifdef CONFIG_PROC_FS
755         struct proc_dir_entry *p;
756         p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
757         if (p == NULL)
758                 return -ENOMEM;
759 #endif
760         register_atm_ioctl(&br2684_ioctl_ops);
761         return 0;
762 }
763
764 static void __exit br2684_exit(void)
765 {
766         struct net_device *net_dev;
767         struct br2684_dev *brdev;
768         struct br2684_vcc *brvcc;
769         deregister_atm_ioctl(&br2684_ioctl_ops);
770
771 #ifdef CONFIG_PROC_FS
772         remove_proc_entry("br2684", atm_proc_root);
773 #endif
774
775         while (!list_empty(&br2684_devs)) {
776                 net_dev = list_entry_brdev(br2684_devs.next);
777                 brdev = BRPRIV(net_dev);
778                 while (!list_empty(&brdev->brvccs)) {
779                         brvcc = list_entry_brvcc(brdev->brvccs.next);
780                         br2684_close_vcc(brvcc);
781                 }
782
783                 list_del(&brdev->br2684_devs);
784                 unregister_netdev(net_dev);
785                 free_netdev(net_dev);
786         }
787 }
788
789 module_init(br2684_init);
790 module_exit(br2684_exit);
791
792 MODULE_AUTHOR("Marcell GAL");
793 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
794 MODULE_LICENSE("GPL");