xref: /openbmc/linux/net/atm/br2684.c (revision 22246614)
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 unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
56 static unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
57 static unsigned char llc_oui_pid_pad[] =
58 			{ LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
59 static unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
60 static 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 *)net_dev->priv;
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 {
192 		skb_push(skb, 2);
193 		if (brdev->payload == p_bridged)
194 			memset(skb->data, 0, 2);
195 	}
196 	skb_debug(skb);
197 
198 	ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
199 	pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
200 	if (!atm_may_send(atmvcc, skb->truesize)) {
201 		/*
202 		 * We free this here for now, because we cannot know in a higher
203 		 * layer whether the skb pointer it supplied wasn't freed yet.
204 		 * Now, it always is.
205 		 */
206 		dev_kfree_skb(skb);
207 		return 0;
208 	}
209 	atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
210 	ATM_SKB(skb)->atm_options = atmvcc->atm_options;
211 	brdev->stats.tx_packets++;
212 	brdev->stats.tx_bytes += skb->len;
213 	atmvcc->send(atmvcc, skb);
214 	return 1;
215 }
216 
217 static inline struct br2684_vcc *pick_outgoing_vcc(struct sk_buff *skb,
218 						   struct br2684_dev *brdev)
219 {
220 	return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);	/* 1 vcc/dev right now */
221 }
222 
223 static int br2684_start_xmit(struct sk_buff *skb, struct net_device *dev)
224 {
225 	struct br2684_dev *brdev = BRPRIV(dev);
226 	struct br2684_vcc *brvcc;
227 
228 	pr_debug("br2684_start_xmit, skb->dst=%p\n", skb->dst);
229 	read_lock(&devs_lock);
230 	brvcc = pick_outgoing_vcc(skb, brdev);
231 	if (brvcc == NULL) {
232 		pr_debug("no vcc attached to dev %s\n", dev->name);
233 		brdev->stats.tx_errors++;
234 		brdev->stats.tx_carrier_errors++;
235 		/* netif_stop_queue(dev); */
236 		dev_kfree_skb(skb);
237 		read_unlock(&devs_lock);
238 		return 0;
239 	}
240 	if (!br2684_xmit_vcc(skb, brdev, brvcc)) {
241 		/*
242 		 * We should probably use netif_*_queue() here, but that
243 		 * involves added complication.  We need to walk before
244 		 * we can run.
245 		 *
246 		 * Don't free here! this pointer might be no longer valid!
247 		 */
248 		brdev->stats.tx_errors++;
249 		brdev->stats.tx_fifo_errors++;
250 	}
251 	read_unlock(&devs_lock);
252 	return 0;
253 }
254 
255 static struct net_device_stats *br2684_get_stats(struct net_device *dev)
256 {
257 	pr_debug("br2684_get_stats\n");
258 	return &BRPRIV(dev)->stats;
259 }
260 
261 /*
262  * We remember when the MAC gets set, so we don't override it later with
263  * the ESI of the ATM card of the first VC
264  */
265 static int (*my_eth_mac_addr) (struct net_device *, void *);
266 static int br2684_mac_addr(struct net_device *dev, void *p)
267 {
268 	int err = my_eth_mac_addr(dev, p);
269 	if (!err)
270 		BRPRIV(dev)->mac_was_set = 1;
271 	return err;
272 }
273 
274 #ifdef CONFIG_ATM_BR2684_IPFILTER
275 /* this IOCTL is experimental. */
276 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
277 {
278 	struct br2684_vcc *brvcc;
279 	struct br2684_filter_set fs;
280 
281 	if (copy_from_user(&fs, arg, sizeof fs))
282 		return -EFAULT;
283 	if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
284 		/*
285 		 * This is really a per-vcc thing, but we can also search
286 		 * by device.
287 		 */
288 		struct br2684_dev *brdev;
289 		read_lock(&devs_lock);
290 		brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
291 		if (brdev == NULL || list_empty(&brdev->brvccs) || brdev->brvccs.next != brdev->brvccs.prev)	/* >1 VCC */
292 			brvcc = NULL;
293 		else
294 			brvcc = list_entry_brvcc(brdev->brvccs.next);
295 		read_unlock(&devs_lock);
296 		if (brvcc == NULL)
297 			return -ESRCH;
298 	} else
299 		brvcc = BR2684_VCC(atmvcc);
300 	memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
301 	return 0;
302 }
303 
304 /* Returns 1 if packet should be dropped */
305 static inline int
306 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
307 {
308 	if (brvcc->filter.netmask == 0)
309 		return 0;	/* no filter in place */
310 	if (type == htons(ETH_P_IP) &&
311 	    (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
312 	     netmask) == brvcc->filter.prefix)
313 		return 0;
314 	if (type == htons(ETH_P_ARP))
315 		return 0;
316 	/*
317 	 * TODO: we should probably filter ARPs too.. don't want to have
318 	 * them returning values that don't make sense, or is that ok?
319 	 */
320 	return 1;		/* drop */
321 }
322 #endif /* CONFIG_ATM_BR2684_IPFILTER */
323 
324 static void br2684_close_vcc(struct br2684_vcc *brvcc)
325 {
326 	pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
327 	write_lock_irq(&devs_lock);
328 	list_del(&brvcc->brvccs);
329 	write_unlock_irq(&devs_lock);
330 	brvcc->atmvcc->user_back = NULL;	/* what about vcc->recvq ??? */
331 	brvcc->old_push(brvcc->atmvcc, NULL);	/* pass on the bad news */
332 	kfree(brvcc);
333 	module_put(THIS_MODULE);
334 }
335 
336 /* when AAL5 PDU comes in: */
337 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
338 {
339 	struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
340 	struct net_device *net_dev = brvcc->device;
341 	struct br2684_dev *brdev = BRPRIV(net_dev);
342 
343 	pr_debug("br2684_push\n");
344 
345 	if (unlikely(skb == NULL)) {
346 		/* skb==NULL means VCC is being destroyed */
347 		br2684_close_vcc(brvcc);
348 		if (list_empty(&brdev->brvccs)) {
349 			write_lock_irq(&devs_lock);
350 			list_del(&brdev->br2684_devs);
351 			write_unlock_irq(&devs_lock);
352 			unregister_netdev(net_dev);
353 			free_netdev(net_dev);
354 		}
355 		return;
356 	}
357 
358 	skb_debug(skb);
359 	atm_return(atmvcc, skb->truesize);
360 	pr_debug("skb from brdev %p\n", brdev);
361 	if (brvcc->encaps == e_llc) {
362 
363 		if (skb->len > 7 && skb->data[7] == 0x01)
364 			__skb_trim(skb, skb->len - 4);
365 
366 		/* accept packets that have "ipv[46]" in the snap header */
367 		if ((skb->len >= (sizeof(llc_oui_ipv4)))
368 		    &&
369 		    (memcmp
370 		     (skb->data, llc_oui_ipv4,
371 		      sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
372 			if (memcmp
373 			    (skb->data + 6, ethertype_ipv6,
374 			     sizeof(ethertype_ipv6)) == 0)
375 				skb->protocol = __constant_htons(ETH_P_IPV6);
376 			else if (memcmp
377 				 (skb->data + 6, ethertype_ipv4,
378 				  sizeof(ethertype_ipv4)) == 0)
379 				skb->protocol = __constant_htons(ETH_P_IP);
380 			else {
381 				brdev->stats.rx_errors++;
382 				dev_kfree_skb(skb);
383 				return;
384 			}
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 			brdev->stats.rx_errors++;
399 			dev_kfree_skb(skb);
400 			return;
401 		}
402 
403 	} else {
404 		/* first 2 chars should be 0 */
405 		if (*((u16 *) (skb->data)) != 0) {
406 			brdev->stats.rx_errors++;
407 			dev_kfree_skb(skb);
408 			return;
409 		}
410 		skb_pull(skb, BR2684_PAD_LEN + ETH_HLEN);	/* pad, dstmac, srcmac, ethtype */
411 		skb->protocol = eth_type_trans(skb, net_dev);
412 	}
413 
414 #ifdef CONFIG_ATM_BR2684_IPFILTER
415 	if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb))) {
416 		brdev->stats.rx_dropped++;
417 		dev_kfree_skb(skb);
418 		return;
419 	}
420 #endif /* CONFIG_ATM_BR2684_IPFILTER */
421 	skb->dev = net_dev;
422 	ATM_SKB(skb)->vcc = atmvcc;	/* needed ? */
423 	pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
424 	skb_debug(skb);
425 	if (unlikely(!(net_dev->flags & IFF_UP))) {
426 		/* sigh, interface is down */
427 		brdev->stats.rx_dropped++;
428 		dev_kfree_skb(skb);
429 		return;
430 	}
431 	brdev->stats.rx_packets++;
432 	brdev->stats.rx_bytes += skb->len;
433 	memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
434 	netif_rx(skb);
435 }
436 
437 /*
438  * Assign a vcc to a dev
439  * Note: we do not have explicit unassign, but look at _push()
440  */
441 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
442 {
443 	int err;
444 	struct br2684_vcc *brvcc;
445 	struct sk_buff *skb;
446 	struct sk_buff_head *rq;
447 	struct br2684_dev *brdev;
448 	struct net_device *net_dev;
449 	struct atm_backend_br2684 be;
450 	unsigned long flags;
451 
452 	if (copy_from_user(&be, arg, sizeof be))
453 		return -EFAULT;
454 	brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
455 	if (!brvcc)
456 		return -ENOMEM;
457 	write_lock_irq(&devs_lock);
458 	net_dev = br2684_find_dev(&be.ifspec);
459 	if (net_dev == NULL) {
460 		printk(KERN_ERR
461 		       "br2684: tried to attach to non-existant device\n");
462 		err = -ENXIO;
463 		goto error;
464 	}
465 	brdev = BRPRIV(net_dev);
466 	if (atmvcc->push == NULL) {
467 		err = -EBADFD;
468 		goto error;
469 	}
470 	if (!list_empty(&brdev->brvccs)) {
471 		/* Only 1 VCC/dev right now */
472 		err = -EEXIST;
473 		goto error;
474 	}
475 	if (be.fcs_in != BR2684_FCSIN_NO || be.fcs_out != BR2684_FCSOUT_NO ||
476 	    be.fcs_auto || be.has_vpiid || be.send_padding || (be.encaps !=
477 							       BR2684_ENCAPS_VC
478 							       && be.encaps !=
479 							       BR2684_ENCAPS_LLC)
480 	    || be.min_size != 0) {
481 		err = -EINVAL;
482 		goto error;
483 	}
484 	pr_debug("br2684_regvcc vcc=%p, encaps=%d, brvcc=%p\n", atmvcc,
485 		 be.encaps, brvcc);
486 	if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
487 		unsigned char *esi = atmvcc->dev->esi;
488 		if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
489 			memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
490 		else
491 			net_dev->dev_addr[2] = 1;
492 	}
493 	list_add(&brvcc->brvccs, &brdev->brvccs);
494 	write_unlock_irq(&devs_lock);
495 	brvcc->device = net_dev;
496 	brvcc->atmvcc = atmvcc;
497 	atmvcc->user_back = brvcc;
498 	brvcc->encaps = (enum br2684_encaps)be.encaps;
499 	brvcc->old_push = atmvcc->push;
500 	barrier();
501 	atmvcc->push = br2684_push;
502 
503 	rq = &sk_atm(atmvcc)->sk_receive_queue;
504 
505 	spin_lock_irqsave(&rq->lock, flags);
506 	if (skb_queue_empty(rq)) {
507 		skb = NULL;
508 	} else {
509 		/* NULL terminate the list.  */
510 		rq->prev->next = NULL;
511 		skb = rq->next;
512 	}
513 	rq->prev = rq->next = (struct sk_buff *)rq;
514 	rq->qlen = 0;
515 	spin_unlock_irqrestore(&rq->lock, flags);
516 
517 	while (skb) {
518 		struct sk_buff *next = skb->next;
519 
520 		skb->next = skb->prev = NULL;
521 		BRPRIV(skb->dev)->stats.rx_bytes -= skb->len;
522 		BRPRIV(skb->dev)->stats.rx_packets--;
523 		br2684_push(atmvcc, skb);
524 
525 		skb = next;
526 	}
527 	__module_get(THIS_MODULE);
528 	return 0;
529       error:
530 	write_unlock_irq(&devs_lock);
531 	kfree(brvcc);
532 	return err;
533 }
534 
535 static void br2684_setup(struct net_device *netdev)
536 {
537 	struct br2684_dev *brdev = BRPRIV(netdev);
538 
539 	ether_setup(netdev);
540 	brdev->net_dev = netdev;
541 
542 	my_eth_mac_addr = netdev->set_mac_address;
543 	netdev->set_mac_address = br2684_mac_addr;
544 	netdev->hard_start_xmit = br2684_start_xmit;
545 	netdev->get_stats = br2684_get_stats;
546 
547 	INIT_LIST_HEAD(&brdev->brvccs);
548 }
549 
550 static void br2684_setup_routed(struct net_device *netdev)
551 {
552 	struct br2684_dev *brdev = BRPRIV(netdev);
553 	brdev->net_dev = netdev;
554 
555 	netdev->hard_header_len = 0;
556 	my_eth_mac_addr = netdev->set_mac_address;
557 	netdev->set_mac_address = br2684_mac_addr;
558 	netdev->hard_start_xmit = br2684_start_xmit;
559 	netdev->get_stats = br2684_get_stats;
560 	netdev->addr_len = 0;
561 	netdev->mtu = 1500;
562 	netdev->type = ARPHRD_PPP;
563 	netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
564 	netdev->tx_queue_len = 100;
565 	INIT_LIST_HEAD(&brdev->brvccs);
566 }
567 
568 static int br2684_create(void __user * arg)
569 {
570 	int err;
571 	struct net_device *netdev;
572 	struct br2684_dev *brdev;
573 	struct atm_newif_br2684 ni;
574 	enum br2684_payload payload;
575 
576 	pr_debug("br2684_create\n");
577 
578 	if (copy_from_user(&ni, arg, sizeof ni)) {
579 		return -EFAULT;
580 	}
581 
582 	if (ni.media & BR2684_FLAG_ROUTED)
583 		payload = p_routed;
584 	else
585 		payload = p_bridged;
586 	ni.media &= 0xffff;	/* strip flags */
587 
588 	if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500) {
589 		return -EINVAL;
590 	}
591 
592 	netdev = alloc_netdev(sizeof(struct br2684_dev),
593 			      ni.ifname[0] ? ni.ifname : "nas%d",
594 			      (payload == p_routed) ?
595 			      br2684_setup_routed : br2684_setup);
596 	if (!netdev)
597 		return -ENOMEM;
598 
599 	brdev = BRPRIV(netdev);
600 
601 	pr_debug("registered netdev %s\n", netdev->name);
602 	/* open, stop, do_ioctl ? */
603 	err = register_netdev(netdev);
604 	if (err < 0) {
605 		printk(KERN_ERR "br2684_create: register_netdev failed\n");
606 		free_netdev(netdev);
607 		return err;
608 	}
609 
610 	write_lock_irq(&devs_lock);
611 	brdev->payload = payload;
612 	brdev->number = list_empty(&br2684_devs) ? 1 :
613 	    BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
614 	list_add_tail(&brdev->br2684_devs, &br2684_devs);
615 	write_unlock_irq(&devs_lock);
616 	return 0;
617 }
618 
619 /*
620  * This handles ioctls actually performed on our vcc - we must return
621  * -ENOIOCTLCMD for any unrecognized ioctl
622  */
623 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
624 			unsigned long arg)
625 {
626 	struct atm_vcc *atmvcc = ATM_SD(sock);
627 	void __user *argp = (void __user *)arg;
628 	atm_backend_t b;
629 
630 	int err;
631 	switch (cmd) {
632 	case ATM_SETBACKEND:
633 	case ATM_NEWBACKENDIF:
634 		err = get_user(b, (atm_backend_t __user *) argp);
635 		if (err)
636 			return -EFAULT;
637 		if (b != ATM_BACKEND_BR2684)
638 			return -ENOIOCTLCMD;
639 		if (!capable(CAP_NET_ADMIN))
640 			return -EPERM;
641 		if (cmd == ATM_SETBACKEND)
642 			return br2684_regvcc(atmvcc, argp);
643 		else
644 			return br2684_create(argp);
645 #ifdef CONFIG_ATM_BR2684_IPFILTER
646 	case BR2684_SETFILT:
647 		if (atmvcc->push != br2684_push)
648 			return -ENOIOCTLCMD;
649 		if (!capable(CAP_NET_ADMIN))
650 			return -EPERM;
651 		err = br2684_setfilt(atmvcc, argp);
652 
653 		return err;
654 #endif /* CONFIG_ATM_BR2684_IPFILTER */
655 	}
656 	return -ENOIOCTLCMD;
657 }
658 
659 static struct atm_ioctl br2684_ioctl_ops = {
660 	.owner = THIS_MODULE,
661 	.ioctl = br2684_ioctl,
662 };
663 
664 #ifdef CONFIG_PROC_FS
665 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
666 	__acquires(devs_lock)
667 {
668 	read_lock(&devs_lock);
669 	return seq_list_start(&br2684_devs, *pos);
670 }
671 
672 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
673 {
674 	return seq_list_next(v, &br2684_devs, pos);
675 }
676 
677 static void br2684_seq_stop(struct seq_file *seq, void *v)
678 	__releases(devs_lock)
679 {
680 	read_unlock(&devs_lock);
681 }
682 
683 static int br2684_seq_show(struct seq_file *seq, void *v)
684 {
685 	const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
686 						    br2684_devs);
687 	const struct net_device *net_dev = brdev->net_dev;
688 	const struct br2684_vcc *brvcc;
689 	DECLARE_MAC_BUF(mac);
690 
691 	seq_printf(seq, "dev %.16s: num=%d, mac=%s (%s)\n",
692 		   net_dev->name,
693 		   brdev->number,
694 		   print_mac(mac, net_dev->dev_addr),
695 		   brdev->mac_was_set ? "set" : "auto");
696 
697 	list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
698 		seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
699 			   ", failed copies %u/%u"
700 			   "\n", brvcc->atmvcc->dev->number,
701 			   brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
702 			   (brvcc->encaps == e_llc) ? "LLC" : "VC",
703 			   (brdev->payload == p_bridged) ? "bridged" : "routed",
704 			   brvcc->copies_failed, brvcc->copies_needed);
705 #ifdef CONFIG_ATM_BR2684_IPFILTER
706 #define b1(var, byte)	((u8 *) &brvcc->filter.var)[byte]
707 #define bs(var)		b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
708 		if (brvcc->filter.netmask != 0)
709 			seq_printf(seq, "    filter=%d.%d.%d.%d/"
710 				   "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
711 #undef bs
712 #undef b1
713 #endif /* CONFIG_ATM_BR2684_IPFILTER */
714 	}
715 	return 0;
716 }
717 
718 static const struct seq_operations br2684_seq_ops = {
719 	.start = br2684_seq_start,
720 	.next = br2684_seq_next,
721 	.stop = br2684_seq_stop,
722 	.show = br2684_seq_show,
723 };
724 
725 static int br2684_proc_open(struct inode *inode, struct file *file)
726 {
727 	return seq_open(file, &br2684_seq_ops);
728 }
729 
730 static const struct file_operations br2684_proc_ops = {
731 	.owner = THIS_MODULE,
732 	.open = br2684_proc_open,
733 	.read = seq_read,
734 	.llseek = seq_lseek,
735 	.release = seq_release,
736 };
737 
738 extern struct proc_dir_entry *atm_proc_root;	/* from proc.c */
739 #endif /* CONFIG_PROC_FS */
740 
741 static int __init br2684_init(void)
742 {
743 #ifdef CONFIG_PROC_FS
744 	struct proc_dir_entry *p;
745 	p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
746 	if (p == NULL)
747 		return -ENOMEM;
748 #endif
749 	register_atm_ioctl(&br2684_ioctl_ops);
750 	return 0;
751 }
752 
753 static void __exit br2684_exit(void)
754 {
755 	struct net_device *net_dev;
756 	struct br2684_dev *brdev;
757 	struct br2684_vcc *brvcc;
758 	deregister_atm_ioctl(&br2684_ioctl_ops);
759 
760 #ifdef CONFIG_PROC_FS
761 	remove_proc_entry("br2684", atm_proc_root);
762 #endif
763 
764 	while (!list_empty(&br2684_devs)) {
765 		net_dev = list_entry_brdev(br2684_devs.next);
766 		brdev = BRPRIV(net_dev);
767 		while (!list_empty(&brdev->brvccs)) {
768 			brvcc = list_entry_brvcc(brdev->brvccs.next);
769 			br2684_close_vcc(brvcc);
770 		}
771 
772 		list_del(&brdev->br2684_devs);
773 		unregister_netdev(net_dev);
774 		free_netdev(net_dev);
775 	}
776 }
777 
778 module_init(br2684_init);
779 module_exit(br2684_exit);
780 
781 MODULE_AUTHOR("Marcell GAL");
782 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
783 MODULE_LICENSE("GPL");
784