xref: /openbmc/linux/net/atm/br2684.c (revision a09d2831)
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 	int mac_was_set;
87 	enum br2684_payload payload;
88 };
89 
90 /*
91  * This lock should be held for writing any time the list of devices or
92  * their attached vcc's could be altered.  It should be held for reading
93  * any time these are being queried.  Note that we sometimes need to
94  * do read-locking under interrupt context, so write locking must block
95  * the current CPU's interrupts
96  */
97 static DEFINE_RWLOCK(devs_lock);
98 
99 static LIST_HEAD(br2684_devs);
100 
101 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
102 {
103 	return (struct br2684_dev *)netdev_priv(net_dev);
104 }
105 
106 static inline struct net_device *list_entry_brdev(const struct list_head *le)
107 {
108 	return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
109 }
110 
111 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
112 {
113 	return (struct br2684_vcc *)(atmvcc->user_back);
114 }
115 
116 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
117 {
118 	return list_entry(le, struct br2684_vcc, brvccs);
119 }
120 
121 /* Caller should hold read_lock(&devs_lock) */
122 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
123 {
124 	struct list_head *lh;
125 	struct net_device *net_dev;
126 	switch (s->method) {
127 	case BR2684_FIND_BYNUM:
128 		list_for_each(lh, &br2684_devs) {
129 			net_dev = list_entry_brdev(lh);
130 			if (BRPRIV(net_dev)->number == s->spec.devnum)
131 				return net_dev;
132 		}
133 		break;
134 	case BR2684_FIND_BYIFNAME:
135 		list_for_each(lh, &br2684_devs) {
136 			net_dev = list_entry_brdev(lh);
137 			if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
138 				return net_dev;
139 		}
140 		break;
141 	}
142 	return NULL;
143 }
144 
145 /* chained vcc->pop function.  Check if we should wake the netif_queue */
146 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
147 {
148 	struct br2684_vcc *brvcc = BR2684_VCC(vcc);
149 	struct net_device *net_dev = skb->dev;
150 
151 	pr_debug("br2684_pop(vcc %p ; net_dev %p )\n", vcc, net_dev);
152 	brvcc->old_pop(vcc, skb);
153 
154 	if (!net_dev)
155 		return;
156 
157 	if (atm_may_send(vcc, 0))
158 		netif_wake_queue(net_dev);
159 
160 }
161 /*
162  * Send a packet out a particular vcc.  Not to useful right now, but paves
163  * the way for multiple vcc's per itf.  Returns true if we can send,
164  * otherwise false
165  */
166 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
167 			   struct br2684_vcc *brvcc)
168 {
169 	struct br2684_dev *brdev = BRPRIV(dev);
170 	struct atm_vcc *atmvcc;
171 	int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
172 
173 	if (skb_headroom(skb) < minheadroom) {
174 		struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
175 		brvcc->copies_needed++;
176 		dev_kfree_skb(skb);
177 		if (skb2 == NULL) {
178 			brvcc->copies_failed++;
179 			return 0;
180 		}
181 		skb = skb2;
182 	}
183 
184 	if (brvcc->encaps == e_llc) {
185 		if (brdev->payload == p_bridged) {
186 			skb_push(skb, sizeof(llc_oui_pid_pad));
187 			skb_copy_to_linear_data(skb, llc_oui_pid_pad,
188 						sizeof(llc_oui_pid_pad));
189 		} else if (brdev->payload == p_routed) {
190 			unsigned short prot = ntohs(skb->protocol);
191 
192 			skb_push(skb, sizeof(llc_oui_ipv4));
193 			switch (prot) {
194 			case ETH_P_IP:
195 				skb_copy_to_linear_data(skb, llc_oui_ipv4,
196 							sizeof(llc_oui_ipv4));
197 				break;
198 			case ETH_P_IPV6:
199 				skb_copy_to_linear_data(skb, llc_oui_ipv6,
200 							sizeof(llc_oui_ipv6));
201 				break;
202 			default:
203 				dev_kfree_skb(skb);
204 				return 0;
205 			}
206 		}
207 	} else { /* e_vc */
208 		if (brdev->payload == p_bridged) {
209 			skb_push(skb, 2);
210 			memset(skb->data, 0, 2);
211 		} else { /* p_routed */
212 			skb_pull(skb, ETH_HLEN);
213 		}
214 	}
215 	skb_debug(skb);
216 
217 	ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
218 	pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
219 	atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
220 	ATM_SKB(skb)->atm_options = atmvcc->atm_options;
221 	dev->stats.tx_packets++;
222 	dev->stats.tx_bytes += skb->len;
223 	atmvcc->send(atmvcc, skb);
224 
225 	if (!atm_may_send(atmvcc, 0)) {
226 		netif_stop_queue(brvcc->device);
227 		/*check for race with br2684_pop*/
228 		if (atm_may_send(atmvcc, 0))
229 			netif_start_queue(brvcc->device);
230 	}
231 
232 	return 1;
233 }
234 
235 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
236 						   const struct br2684_dev *brdev)
237 {
238 	return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);	/* 1 vcc/dev right now */
239 }
240 
241 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
242 				     struct net_device *dev)
243 {
244 	struct br2684_dev *brdev = BRPRIV(dev);
245 	struct br2684_vcc *brvcc;
246 
247 	pr_debug("br2684_start_xmit, skb_dst(skb)=%p\n", skb_dst(skb));
248 	read_lock(&devs_lock);
249 	brvcc = pick_outgoing_vcc(skb, brdev);
250 	if (brvcc == NULL) {
251 		pr_debug("no vcc attached to dev %s\n", dev->name);
252 		dev->stats.tx_errors++;
253 		dev->stats.tx_carrier_errors++;
254 		/* netif_stop_queue(dev); */
255 		dev_kfree_skb(skb);
256 		read_unlock(&devs_lock);
257 		return NETDEV_TX_OK;
258 	}
259 	if (!br2684_xmit_vcc(skb, dev, brvcc)) {
260 		/*
261 		 * We should probably use netif_*_queue() here, but that
262 		 * involves added complication.  We need to walk before
263 		 * we can run.
264 		 *
265 		 * Don't free here! this pointer might be no longer valid!
266 		 */
267 		dev->stats.tx_errors++;
268 		dev->stats.tx_fifo_errors++;
269 	}
270 	read_unlock(&devs_lock);
271 	return NETDEV_TX_OK;
272 }
273 
274 /*
275  * We remember when the MAC gets set, so we don't override it later with
276  * the ESI of the ATM card of the first VC
277  */
278 static int br2684_mac_addr(struct net_device *dev, void *p)
279 {
280 	int err = eth_mac_addr(dev, p);
281 	if (!err)
282 		BRPRIV(dev)->mac_was_set = 1;
283 	return err;
284 }
285 
286 #ifdef CONFIG_ATM_BR2684_IPFILTER
287 /* this IOCTL is experimental. */
288 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
289 {
290 	struct br2684_vcc *brvcc;
291 	struct br2684_filter_set fs;
292 
293 	if (copy_from_user(&fs, arg, sizeof fs))
294 		return -EFAULT;
295 	if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
296 		/*
297 		 * This is really a per-vcc thing, but we can also search
298 		 * by device.
299 		 */
300 		struct br2684_dev *brdev;
301 		read_lock(&devs_lock);
302 		brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
303 		if (brdev == NULL || list_empty(&brdev->brvccs) || brdev->brvccs.next != brdev->brvccs.prev)	/* >1 VCC */
304 			brvcc = NULL;
305 		else
306 			brvcc = list_entry_brvcc(brdev->brvccs.next);
307 		read_unlock(&devs_lock);
308 		if (brvcc == NULL)
309 			return -ESRCH;
310 	} else
311 		brvcc = BR2684_VCC(atmvcc);
312 	memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
313 	return 0;
314 }
315 
316 /* Returns 1 if packet should be dropped */
317 static inline int
318 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
319 {
320 	if (brvcc->filter.netmask == 0)
321 		return 0;	/* no filter in place */
322 	if (type == htons(ETH_P_IP) &&
323 	    (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
324 	     netmask) == brvcc->filter.prefix)
325 		return 0;
326 	if (type == htons(ETH_P_ARP))
327 		return 0;
328 	/*
329 	 * TODO: we should probably filter ARPs too.. don't want to have
330 	 * them returning values that don't make sense, or is that ok?
331 	 */
332 	return 1;		/* drop */
333 }
334 #endif /* CONFIG_ATM_BR2684_IPFILTER */
335 
336 static void br2684_close_vcc(struct br2684_vcc *brvcc)
337 {
338 	pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
339 	write_lock_irq(&devs_lock);
340 	list_del(&brvcc->brvccs);
341 	write_unlock_irq(&devs_lock);
342 	brvcc->atmvcc->user_back = NULL;	/* what about vcc->recvq ??? */
343 	brvcc->old_push(brvcc->atmvcc, NULL);	/* pass on the bad news */
344 	kfree(brvcc);
345 	module_put(THIS_MODULE);
346 }
347 
348 /* when AAL5 PDU comes in: */
349 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
350 {
351 	struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
352 	struct net_device *net_dev = brvcc->device;
353 	struct br2684_dev *brdev = BRPRIV(net_dev);
354 
355 	pr_debug("br2684_push\n");
356 
357 	if (unlikely(skb == NULL)) {
358 		/* skb==NULL means VCC is being destroyed */
359 		br2684_close_vcc(brvcc);
360 		if (list_empty(&brdev->brvccs)) {
361 			write_lock_irq(&devs_lock);
362 			list_del(&brdev->br2684_devs);
363 			write_unlock_irq(&devs_lock);
364 			unregister_netdev(net_dev);
365 			free_netdev(net_dev);
366 		}
367 		return;
368 	}
369 
370 	skb_debug(skb);
371 	atm_return(atmvcc, skb->truesize);
372 	pr_debug("skb from brdev %p\n", brdev);
373 	if (brvcc->encaps == e_llc) {
374 
375 		if (skb->len > 7 && skb->data[7] == 0x01)
376 			__skb_trim(skb, skb->len - 4);
377 
378 		/* accept packets that have "ipv[46]" in the snap header */
379 		if ((skb->len >= (sizeof(llc_oui_ipv4)))
380 		    &&
381 		    (memcmp
382 		     (skb->data, llc_oui_ipv4,
383 		      sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
384 			if (memcmp
385 			    (skb->data + 6, ethertype_ipv6,
386 			     sizeof(ethertype_ipv6)) == 0)
387 				skb->protocol = htons(ETH_P_IPV6);
388 			else if (memcmp
389 				 (skb->data + 6, ethertype_ipv4,
390 				  sizeof(ethertype_ipv4)) == 0)
391 				skb->protocol = htons(ETH_P_IP);
392 			else
393 				goto error;
394 			skb_pull(skb, sizeof(llc_oui_ipv4));
395 			skb_reset_network_header(skb);
396 			skb->pkt_type = PACKET_HOST;
397 			/*
398 			 * Let us waste some time for checking the encapsulation.
399 			 * Note, that only 7 char is checked so frames with a valid FCS
400 			 * are also accepted (but FCS is not checked of course).
401 			 */
402 		} else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
403 			   (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
404 			skb_pull(skb, sizeof(llc_oui_pid_pad));
405 			skb->protocol = eth_type_trans(skb, net_dev);
406 		} else
407 			goto error;
408 
409 	} else { /* e_vc */
410 		if (brdev->payload == p_routed) {
411 			struct iphdr *iph;
412 
413 			skb_reset_network_header(skb);
414 			iph = ip_hdr(skb);
415 			if (iph->version == 4)
416 				skb->protocol = htons(ETH_P_IP);
417 			else if (iph->version == 6)
418 				skb->protocol = htons(ETH_P_IPV6);
419 			else
420 				goto error;
421 			skb->pkt_type = PACKET_HOST;
422 		} else { /* p_bridged */
423 			/* first 2 chars should be 0 */
424 			if (*((u16 *) (skb->data)) != 0)
425 				goto error;
426 			skb_pull(skb, BR2684_PAD_LEN);
427 			skb->protocol = eth_type_trans(skb, net_dev);
428 		}
429 	}
430 
431 #ifdef CONFIG_ATM_BR2684_IPFILTER
432 	if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
433 		goto dropped;
434 #endif /* CONFIG_ATM_BR2684_IPFILTER */
435 	skb->dev = net_dev;
436 	ATM_SKB(skb)->vcc = atmvcc;	/* needed ? */
437 	pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
438 	skb_debug(skb);
439 	/* sigh, interface is down? */
440 	if (unlikely(!(net_dev->flags & IFF_UP)))
441 		goto dropped;
442 	net_dev->stats.rx_packets++;
443 	net_dev->stats.rx_bytes += skb->len;
444 	memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
445 	netif_rx(skb);
446 	return;
447 
448 dropped:
449 	net_dev->stats.rx_dropped++;
450 	goto free_skb;
451 error:
452 	net_dev->stats.rx_errors++;
453 free_skb:
454 	dev_kfree_skb(skb);
455 	return;
456 }
457 
458 /*
459  * Assign a vcc to a dev
460  * Note: we do not have explicit unassign, but look at _push()
461  */
462 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
463 {
464 	struct sk_buff_head queue;
465 	int err;
466 	struct br2684_vcc *brvcc;
467 	struct sk_buff *skb, *tmp;
468 	struct sk_buff_head *rq;
469 	struct br2684_dev *brdev;
470 	struct net_device *net_dev;
471 	struct atm_backend_br2684 be;
472 	unsigned long flags;
473 
474 	if (copy_from_user(&be, arg, sizeof be))
475 		return -EFAULT;
476 	brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
477 	if (!brvcc)
478 		return -ENOMEM;
479 	write_lock_irq(&devs_lock);
480 	net_dev = br2684_find_dev(&be.ifspec);
481 	if (net_dev == NULL) {
482 		printk(KERN_ERR
483 		       "br2684: tried to attach to non-existant device\n");
484 		err = -ENXIO;
485 		goto error;
486 	}
487 	brdev = BRPRIV(net_dev);
488 	if (atmvcc->push == NULL) {
489 		err = -EBADFD;
490 		goto error;
491 	}
492 	if (!list_empty(&brdev->brvccs)) {
493 		/* Only 1 VCC/dev right now */
494 		err = -EEXIST;
495 		goto error;
496 	}
497 	if (be.fcs_in != BR2684_FCSIN_NO || be.fcs_out != BR2684_FCSOUT_NO ||
498 	    be.fcs_auto || be.has_vpiid || be.send_padding || (be.encaps !=
499 							       BR2684_ENCAPS_VC
500 							       && be.encaps !=
501 							       BR2684_ENCAPS_LLC)
502 	    || be.min_size != 0) {
503 		err = -EINVAL;
504 		goto error;
505 	}
506 	pr_debug("br2684_regvcc vcc=%p, encaps=%d, brvcc=%p\n", atmvcc,
507 		 be.encaps, brvcc);
508 	if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
509 		unsigned char *esi = atmvcc->dev->esi;
510 		if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
511 			memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
512 		else
513 			net_dev->dev_addr[2] = 1;
514 	}
515 	list_add(&brvcc->brvccs, &brdev->brvccs);
516 	write_unlock_irq(&devs_lock);
517 	brvcc->device = net_dev;
518 	brvcc->atmvcc = atmvcc;
519 	atmvcc->user_back = brvcc;
520 	brvcc->encaps = (enum br2684_encaps)be.encaps;
521 	brvcc->old_push = atmvcc->push;
522 	brvcc->old_pop = atmvcc->pop;
523 	barrier();
524 	atmvcc->push = br2684_push;
525 	atmvcc->pop = br2684_pop;
526 
527 	__skb_queue_head_init(&queue);
528 	rq = &sk_atm(atmvcc)->sk_receive_queue;
529 
530 	spin_lock_irqsave(&rq->lock, flags);
531 	skb_queue_splice_init(rq, &queue);
532 	spin_unlock_irqrestore(&rq->lock, flags);
533 
534 	skb_queue_walk_safe(&queue, skb, tmp) {
535 		struct net_device *dev = skb->dev;
536 
537 		dev->stats.rx_bytes -= skb->len;
538 		dev->stats.rx_packets--;
539 
540 		br2684_push(atmvcc, skb);
541 	}
542 	__module_get(THIS_MODULE);
543 	return 0;
544       error:
545 	write_unlock_irq(&devs_lock);
546 	kfree(brvcc);
547 	return err;
548 }
549 
550 static const struct net_device_ops br2684_netdev_ops = {
551 	.ndo_start_xmit 	= br2684_start_xmit,
552 	.ndo_set_mac_address	= br2684_mac_addr,
553 	.ndo_change_mtu		= eth_change_mtu,
554 	.ndo_validate_addr	= eth_validate_addr,
555 };
556 
557 static const struct net_device_ops br2684_netdev_ops_routed = {
558 	.ndo_start_xmit 	= br2684_start_xmit,
559 	.ndo_set_mac_address	= br2684_mac_addr,
560 	.ndo_change_mtu		= eth_change_mtu
561 };
562 
563 static void br2684_setup(struct net_device *netdev)
564 {
565 	struct br2684_dev *brdev = BRPRIV(netdev);
566 
567 	ether_setup(netdev);
568 	brdev->net_dev = netdev;
569 
570 	netdev->netdev_ops = &br2684_netdev_ops;
571 
572 	INIT_LIST_HEAD(&brdev->brvccs);
573 }
574 
575 static void br2684_setup_routed(struct net_device *netdev)
576 {
577 	struct br2684_dev *brdev = BRPRIV(netdev);
578 
579 	brdev->net_dev = netdev;
580 	netdev->hard_header_len = 0;
581 	netdev->netdev_ops = &br2684_netdev_ops_routed;
582 	netdev->addr_len = 0;
583 	netdev->mtu = 1500;
584 	netdev->type = ARPHRD_PPP;
585 	netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
586 	netdev->tx_queue_len = 100;
587 	INIT_LIST_HEAD(&brdev->brvccs);
588 }
589 
590 static int br2684_create(void __user * arg)
591 {
592 	int err;
593 	struct net_device *netdev;
594 	struct br2684_dev *brdev;
595 	struct atm_newif_br2684 ni;
596 	enum br2684_payload payload;
597 
598 	pr_debug("br2684_create\n");
599 
600 	if (copy_from_user(&ni, arg, sizeof ni)) {
601 		return -EFAULT;
602 	}
603 
604 	if (ni.media & BR2684_FLAG_ROUTED)
605 		payload = p_routed;
606 	else
607 		payload = p_bridged;
608 	ni.media &= 0xffff;	/* strip flags */
609 
610 	if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500) {
611 		return -EINVAL;
612 	}
613 
614 	netdev = alloc_netdev(sizeof(struct br2684_dev),
615 			      ni.ifname[0] ? ni.ifname : "nas%d",
616 			      (payload == p_routed) ?
617 			      br2684_setup_routed : br2684_setup);
618 	if (!netdev)
619 		return -ENOMEM;
620 
621 	brdev = BRPRIV(netdev);
622 
623 	pr_debug("registered netdev %s\n", netdev->name);
624 	/* open, stop, do_ioctl ? */
625 	err = register_netdev(netdev);
626 	if (err < 0) {
627 		printk(KERN_ERR "br2684_create: register_netdev failed\n");
628 		free_netdev(netdev);
629 		return err;
630 	}
631 
632 	write_lock_irq(&devs_lock);
633 	brdev->payload = payload;
634 	brdev->number = list_empty(&br2684_devs) ? 1 :
635 	    BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
636 	list_add_tail(&brdev->br2684_devs, &br2684_devs);
637 	write_unlock_irq(&devs_lock);
638 	return 0;
639 }
640 
641 /*
642  * This handles ioctls actually performed on our vcc - we must return
643  * -ENOIOCTLCMD for any unrecognized ioctl
644  */
645 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
646 			unsigned long arg)
647 {
648 	struct atm_vcc *atmvcc = ATM_SD(sock);
649 	void __user *argp = (void __user *)arg;
650 	atm_backend_t b;
651 
652 	int err;
653 	switch (cmd) {
654 	case ATM_SETBACKEND:
655 	case ATM_NEWBACKENDIF:
656 		err = get_user(b, (atm_backend_t __user *) argp);
657 		if (err)
658 			return -EFAULT;
659 		if (b != ATM_BACKEND_BR2684)
660 			return -ENOIOCTLCMD;
661 		if (!capable(CAP_NET_ADMIN))
662 			return -EPERM;
663 		if (cmd == ATM_SETBACKEND)
664 			return br2684_regvcc(atmvcc, argp);
665 		else
666 			return br2684_create(argp);
667 #ifdef CONFIG_ATM_BR2684_IPFILTER
668 	case BR2684_SETFILT:
669 		if (atmvcc->push != br2684_push)
670 			return -ENOIOCTLCMD;
671 		if (!capable(CAP_NET_ADMIN))
672 			return -EPERM;
673 		err = br2684_setfilt(atmvcc, argp);
674 
675 		return err;
676 #endif /* CONFIG_ATM_BR2684_IPFILTER */
677 	}
678 	return -ENOIOCTLCMD;
679 }
680 
681 static struct atm_ioctl br2684_ioctl_ops = {
682 	.owner = THIS_MODULE,
683 	.ioctl = br2684_ioctl,
684 };
685 
686 #ifdef CONFIG_PROC_FS
687 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
688 	__acquires(devs_lock)
689 {
690 	read_lock(&devs_lock);
691 	return seq_list_start(&br2684_devs, *pos);
692 }
693 
694 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
695 {
696 	return seq_list_next(v, &br2684_devs, pos);
697 }
698 
699 static void br2684_seq_stop(struct seq_file *seq, void *v)
700 	__releases(devs_lock)
701 {
702 	read_unlock(&devs_lock);
703 }
704 
705 static int br2684_seq_show(struct seq_file *seq, void *v)
706 {
707 	const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
708 						    br2684_devs);
709 	const struct net_device *net_dev = brdev->net_dev;
710 	const struct br2684_vcc *brvcc;
711 
712 	seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
713 		   net_dev->name,
714 		   brdev->number,
715 		   net_dev->dev_addr,
716 		   brdev->mac_was_set ? "set" : "auto");
717 
718 	list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
719 		seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
720 			   ", failed copies %u/%u"
721 			   "\n", brvcc->atmvcc->dev->number,
722 			   brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
723 			   (brvcc->encaps == e_llc) ? "LLC" : "VC",
724 			   (brdev->payload == p_bridged) ? "bridged" : "routed",
725 			   brvcc->copies_failed, brvcc->copies_needed);
726 #ifdef CONFIG_ATM_BR2684_IPFILTER
727 #define b1(var, byte)	((u8 *) &brvcc->filter.var)[byte]
728 #define bs(var)		b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
729 		if (brvcc->filter.netmask != 0)
730 			seq_printf(seq, "    filter=%d.%d.%d.%d/"
731 				   "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
732 #undef bs
733 #undef b1
734 #endif /* CONFIG_ATM_BR2684_IPFILTER */
735 	}
736 	return 0;
737 }
738 
739 static const struct seq_operations br2684_seq_ops = {
740 	.start = br2684_seq_start,
741 	.next = br2684_seq_next,
742 	.stop = br2684_seq_stop,
743 	.show = br2684_seq_show,
744 };
745 
746 static int br2684_proc_open(struct inode *inode, struct file *file)
747 {
748 	return seq_open(file, &br2684_seq_ops);
749 }
750 
751 static const struct file_operations br2684_proc_ops = {
752 	.owner = THIS_MODULE,
753 	.open = br2684_proc_open,
754 	.read = seq_read,
755 	.llseek = seq_lseek,
756 	.release = seq_release,
757 };
758 
759 extern struct proc_dir_entry *atm_proc_root;	/* from proc.c */
760 #endif /* CONFIG_PROC_FS */
761 
762 static int __init br2684_init(void)
763 {
764 #ifdef CONFIG_PROC_FS
765 	struct proc_dir_entry *p;
766 	p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
767 	if (p == NULL)
768 		return -ENOMEM;
769 #endif
770 	register_atm_ioctl(&br2684_ioctl_ops);
771 	return 0;
772 }
773 
774 static void __exit br2684_exit(void)
775 {
776 	struct net_device *net_dev;
777 	struct br2684_dev *brdev;
778 	struct br2684_vcc *brvcc;
779 	deregister_atm_ioctl(&br2684_ioctl_ops);
780 
781 #ifdef CONFIG_PROC_FS
782 	remove_proc_entry("br2684", atm_proc_root);
783 #endif
784 
785 	while (!list_empty(&br2684_devs)) {
786 		net_dev = list_entry_brdev(br2684_devs.next);
787 		brdev = BRPRIV(net_dev);
788 		while (!list_empty(&brdev->brvccs)) {
789 			brvcc = list_entry_brvcc(brdev->brvccs.next);
790 			br2684_close_vcc(brvcc);
791 		}
792 
793 		list_del(&brdev->br2684_devs);
794 		unregister_netdev(net_dev);
795 		free_netdev(net_dev);
796 	}
797 }
798 
799 module_init(br2684_init);
800 module_exit(br2684_exit);
801 
802 MODULE_AUTHOR("Marcell GAL");
803 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
804 MODULE_LICENSE("GPL");
805