xref: /openbmc/linux/net/atm/br2684.c (revision 615c36f5)
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 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
10 
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/list.h>
15 #include <linux/netdevice.h>
16 #include <linux/skbuff.h>
17 #include <linux/etherdevice.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/ip.h>
20 #include <linux/uaccess.h>
21 #include <linux/slab.h>
22 #include <net/arp.h>
23 #include <linux/atm.h>
24 #include <linux/atmdev.h>
25 #include <linux/capability.h>
26 #include <linux/seq_file.h>
27 
28 #include <linux/atmbr2684.h>
29 
30 #include "common.h"
31 
32 static void skb_debug(const struct sk_buff *skb)
33 {
34 #ifdef SKB_DEBUG
35 #define NUM2PRINT 50
36 	print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
37 		       16, 1, skb->data, min(NUM2PRINT, skb->len), true);
38 #endif
39 }
40 
41 #define BR2684_ETHERTYPE_LEN	2
42 #define BR2684_PAD_LEN		2
43 
44 #define LLC		0xaa, 0xaa, 0x03
45 #define SNAP_BRIDGED	0x00, 0x80, 0xc2
46 #define SNAP_ROUTED	0x00, 0x00, 0x00
47 #define PID_ETHERNET	0x00, 0x07
48 #define ETHERTYPE_IPV4	0x08, 0x00
49 #define ETHERTYPE_IPV6	0x86, 0xdd
50 #define PAD_BRIDGED	0x00, 0x00
51 
52 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
53 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
54 static const unsigned char llc_oui_pid_pad[] =
55 			{ LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
56 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
57 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
58 
59 enum br2684_encaps {
60 	e_vc = BR2684_ENCAPS_VC,
61 	e_llc = BR2684_ENCAPS_LLC,
62 };
63 
64 struct br2684_vcc {
65 	struct atm_vcc *atmvcc;
66 	struct net_device *device;
67 	/* keep old push, pop functions for chaining */
68 	void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
69 	void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
70 	enum br2684_encaps encaps;
71 	struct list_head brvccs;
72 #ifdef CONFIG_ATM_BR2684_IPFILTER
73 	struct br2684_filter filter;
74 #endif /* CONFIG_ATM_BR2684_IPFILTER */
75 	unsigned copies_needed, copies_failed;
76 };
77 
78 struct br2684_dev {
79 	struct net_device *net_dev;
80 	struct list_head br2684_devs;
81 	int number;
82 	struct list_head brvccs;	/* one device <=> one vcc (before xmas) */
83 	int mac_was_set;
84 	enum br2684_payload payload;
85 };
86 
87 /*
88  * This lock should be held for writing any time the list of devices or
89  * their attached vcc's could be altered.  It should be held for reading
90  * any time these are being queried.  Note that we sometimes need to
91  * do read-locking under interrupt context, so write locking must block
92  * the current CPU's interrupts
93  */
94 static DEFINE_RWLOCK(devs_lock);
95 
96 static LIST_HEAD(br2684_devs);
97 
98 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
99 {
100 	return netdev_priv(net_dev);
101 }
102 
103 static inline struct net_device *list_entry_brdev(const struct list_head *le)
104 {
105 	return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
106 }
107 
108 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
109 {
110 	return (struct br2684_vcc *)(atmvcc->user_back);
111 }
112 
113 static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
114 {
115 	return list_entry(le, struct br2684_vcc, brvccs);
116 }
117 
118 /* Caller should hold read_lock(&devs_lock) */
119 static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
120 {
121 	struct list_head *lh;
122 	struct net_device *net_dev;
123 	switch (s->method) {
124 	case BR2684_FIND_BYNUM:
125 		list_for_each(lh, &br2684_devs) {
126 			net_dev = list_entry_brdev(lh);
127 			if (BRPRIV(net_dev)->number == s->spec.devnum)
128 				return net_dev;
129 		}
130 		break;
131 	case BR2684_FIND_BYIFNAME:
132 		list_for_each(lh, &br2684_devs) {
133 			net_dev = list_entry_brdev(lh);
134 			if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
135 				return net_dev;
136 		}
137 		break;
138 	}
139 	return NULL;
140 }
141 
142 static int atm_dev_event(struct notifier_block *this, unsigned long event,
143 		 void *arg)
144 {
145 	struct atm_dev *atm_dev = arg;
146 	struct list_head *lh;
147 	struct net_device *net_dev;
148 	struct br2684_vcc *brvcc;
149 	struct atm_vcc *atm_vcc;
150 	unsigned long flags;
151 
152 	pr_debug("event=%ld dev=%p\n", event, atm_dev);
153 
154 	read_lock_irqsave(&devs_lock, flags);
155 	list_for_each(lh, &br2684_devs) {
156 		net_dev = list_entry_brdev(lh);
157 
158 		list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
159 			atm_vcc = brvcc->atmvcc;
160 			if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
161 
162 				if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
163 					netif_carrier_off(net_dev);
164 				else
165 					netif_carrier_on(net_dev);
166 
167 			}
168 		}
169 	}
170 	read_unlock_irqrestore(&devs_lock, flags);
171 
172 	return NOTIFY_DONE;
173 }
174 
175 static struct notifier_block atm_dev_notifier = {
176 	.notifier_call = atm_dev_event,
177 };
178 
179 /* chained vcc->pop function.  Check if we should wake the netif_queue */
180 static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
181 {
182 	struct br2684_vcc *brvcc = BR2684_VCC(vcc);
183 	struct net_device *net_dev = skb->dev;
184 
185 	pr_debug("(vcc %p ; net_dev %p )\n", vcc, net_dev);
186 	brvcc->old_pop(vcc, skb);
187 
188 	if (!net_dev)
189 		return;
190 
191 	if (atm_may_send(vcc, 0))
192 		netif_wake_queue(net_dev);
193 
194 }
195 /*
196  * Send a packet out a particular vcc.  Not to useful right now, but paves
197  * the way for multiple vcc's per itf.  Returns true if we can send,
198  * otherwise false
199  */
200 static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
201 			   struct br2684_vcc *brvcc)
202 {
203 	struct br2684_dev *brdev = BRPRIV(dev);
204 	struct atm_vcc *atmvcc;
205 	int minheadroom = (brvcc->encaps == e_llc) ? 10 : 2;
206 
207 	if (skb_headroom(skb) < minheadroom) {
208 		struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
209 		brvcc->copies_needed++;
210 		dev_kfree_skb(skb);
211 		if (skb2 == NULL) {
212 			brvcc->copies_failed++;
213 			return 0;
214 		}
215 		skb = skb2;
216 	}
217 
218 	if (brvcc->encaps == e_llc) {
219 		if (brdev->payload == p_bridged) {
220 			skb_push(skb, sizeof(llc_oui_pid_pad));
221 			skb_copy_to_linear_data(skb, llc_oui_pid_pad,
222 						sizeof(llc_oui_pid_pad));
223 		} else if (brdev->payload == p_routed) {
224 			unsigned short prot = ntohs(skb->protocol);
225 
226 			skb_push(skb, sizeof(llc_oui_ipv4));
227 			switch (prot) {
228 			case ETH_P_IP:
229 				skb_copy_to_linear_data(skb, llc_oui_ipv4,
230 							sizeof(llc_oui_ipv4));
231 				break;
232 			case ETH_P_IPV6:
233 				skb_copy_to_linear_data(skb, llc_oui_ipv6,
234 							sizeof(llc_oui_ipv6));
235 				break;
236 			default:
237 				dev_kfree_skb(skb);
238 				return 0;
239 			}
240 		}
241 	} else { /* e_vc */
242 		if (brdev->payload == p_bridged) {
243 			skb_push(skb, 2);
244 			memset(skb->data, 0, 2);
245 		}
246 	}
247 	skb_debug(skb);
248 
249 	ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
250 	pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
251 	atomic_add(skb->truesize, &sk_atm(atmvcc)->sk_wmem_alloc);
252 	ATM_SKB(skb)->atm_options = atmvcc->atm_options;
253 	dev->stats.tx_packets++;
254 	dev->stats.tx_bytes += skb->len;
255 	atmvcc->send(atmvcc, skb);
256 
257 	if (!atm_may_send(atmvcc, 0)) {
258 		netif_stop_queue(brvcc->device);
259 		/*check for race with br2684_pop*/
260 		if (atm_may_send(atmvcc, 0))
261 			netif_start_queue(brvcc->device);
262 	}
263 
264 	return 1;
265 }
266 
267 static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
268 						   const struct br2684_dev *brdev)
269 {
270 	return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);	/* 1 vcc/dev right now */
271 }
272 
273 static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
274 				     struct net_device *dev)
275 {
276 	struct br2684_dev *brdev = BRPRIV(dev);
277 	struct br2684_vcc *brvcc;
278 
279 	pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
280 	read_lock(&devs_lock);
281 	brvcc = pick_outgoing_vcc(skb, brdev);
282 	if (brvcc == NULL) {
283 		pr_debug("no vcc attached to dev %s\n", dev->name);
284 		dev->stats.tx_errors++;
285 		dev->stats.tx_carrier_errors++;
286 		/* netif_stop_queue(dev); */
287 		dev_kfree_skb(skb);
288 		read_unlock(&devs_lock);
289 		return NETDEV_TX_OK;
290 	}
291 	if (!br2684_xmit_vcc(skb, dev, brvcc)) {
292 		/*
293 		 * We should probably use netif_*_queue() here, but that
294 		 * involves added complication.  We need to walk before
295 		 * we can run.
296 		 *
297 		 * Don't free here! this pointer might be no longer valid!
298 		 */
299 		dev->stats.tx_errors++;
300 		dev->stats.tx_fifo_errors++;
301 	}
302 	read_unlock(&devs_lock);
303 	return NETDEV_TX_OK;
304 }
305 
306 /*
307  * We remember when the MAC gets set, so we don't override it later with
308  * the ESI of the ATM card of the first VC
309  */
310 static int br2684_mac_addr(struct net_device *dev, void *p)
311 {
312 	int err = eth_mac_addr(dev, p);
313 	if (!err)
314 		BRPRIV(dev)->mac_was_set = 1;
315 	return err;
316 }
317 
318 #ifdef CONFIG_ATM_BR2684_IPFILTER
319 /* this IOCTL is experimental. */
320 static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
321 {
322 	struct br2684_vcc *brvcc;
323 	struct br2684_filter_set fs;
324 
325 	if (copy_from_user(&fs, arg, sizeof fs))
326 		return -EFAULT;
327 	if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
328 		/*
329 		 * This is really a per-vcc thing, but we can also search
330 		 * by device.
331 		 */
332 		struct br2684_dev *brdev;
333 		read_lock(&devs_lock);
334 		brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
335 		if (brdev == NULL || list_empty(&brdev->brvccs) ||
336 		    brdev->brvccs.next != brdev->brvccs.prev)	/* >1 VCC */
337 			brvcc = NULL;
338 		else
339 			brvcc = list_entry_brvcc(brdev->brvccs.next);
340 		read_unlock(&devs_lock);
341 		if (brvcc == NULL)
342 			return -ESRCH;
343 	} else
344 		brvcc = BR2684_VCC(atmvcc);
345 	memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
346 	return 0;
347 }
348 
349 /* Returns 1 if packet should be dropped */
350 static inline int
351 packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
352 {
353 	if (brvcc->filter.netmask == 0)
354 		return 0;	/* no filter in place */
355 	if (type == htons(ETH_P_IP) &&
356 	    (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
357 	     netmask) == brvcc->filter.prefix)
358 		return 0;
359 	if (type == htons(ETH_P_ARP))
360 		return 0;
361 	/*
362 	 * TODO: we should probably filter ARPs too.. don't want to have
363 	 * them returning values that don't make sense, or is that ok?
364 	 */
365 	return 1;		/* drop */
366 }
367 #endif /* CONFIG_ATM_BR2684_IPFILTER */
368 
369 static void br2684_close_vcc(struct br2684_vcc *brvcc)
370 {
371 	pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
372 	write_lock_irq(&devs_lock);
373 	list_del(&brvcc->brvccs);
374 	write_unlock_irq(&devs_lock);
375 	brvcc->atmvcc->user_back = NULL;	/* what about vcc->recvq ??? */
376 	brvcc->old_push(brvcc->atmvcc, NULL);	/* pass on the bad news */
377 	kfree(brvcc);
378 	module_put(THIS_MODULE);
379 }
380 
381 /* when AAL5 PDU comes in: */
382 static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
383 {
384 	struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
385 	struct net_device *net_dev = brvcc->device;
386 	struct br2684_dev *brdev = BRPRIV(net_dev);
387 
388 	pr_debug("\n");
389 
390 	if (unlikely(skb == NULL)) {
391 		/* skb==NULL means VCC is being destroyed */
392 		br2684_close_vcc(brvcc);
393 		if (list_empty(&brdev->brvccs)) {
394 			write_lock_irq(&devs_lock);
395 			list_del(&brdev->br2684_devs);
396 			write_unlock_irq(&devs_lock);
397 			unregister_netdev(net_dev);
398 			free_netdev(net_dev);
399 		}
400 		return;
401 	}
402 
403 	skb_debug(skb);
404 	atm_return(atmvcc, skb->truesize);
405 	pr_debug("skb from brdev %p\n", brdev);
406 	if (brvcc->encaps == e_llc) {
407 
408 		if (skb->len > 7 && skb->data[7] == 0x01)
409 			__skb_trim(skb, skb->len - 4);
410 
411 		/* accept packets that have "ipv[46]" in the snap header */
412 		if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
413 		    (memcmp(skb->data, llc_oui_ipv4,
414 			    sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
415 			if (memcmp(skb->data + 6, ethertype_ipv6,
416 				   sizeof(ethertype_ipv6)) == 0)
417 				skb->protocol = htons(ETH_P_IPV6);
418 			else if (memcmp(skb->data + 6, ethertype_ipv4,
419 					sizeof(ethertype_ipv4)) == 0)
420 				skb->protocol = htons(ETH_P_IP);
421 			else
422 				goto error;
423 			skb_pull(skb, sizeof(llc_oui_ipv4));
424 			skb_reset_network_header(skb);
425 			skb->pkt_type = PACKET_HOST;
426 		/*
427 		 * Let us waste some time for checking the encapsulation.
428 		 * Note, that only 7 char is checked so frames with a valid FCS
429 		 * are also accepted (but FCS is not checked of course).
430 		 */
431 		} else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
432 			   (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
433 			skb_pull(skb, sizeof(llc_oui_pid_pad));
434 			skb->protocol = eth_type_trans(skb, net_dev);
435 		} else
436 			goto error;
437 
438 	} else { /* e_vc */
439 		if (brdev->payload == p_routed) {
440 			struct iphdr *iph;
441 
442 			skb_reset_network_header(skb);
443 			iph = ip_hdr(skb);
444 			if (iph->version == 4)
445 				skb->protocol = htons(ETH_P_IP);
446 			else if (iph->version == 6)
447 				skb->protocol = htons(ETH_P_IPV6);
448 			else
449 				goto error;
450 			skb->pkt_type = PACKET_HOST;
451 		} else { /* p_bridged */
452 			/* first 2 chars should be 0 */
453 			if (*((u16 *) (skb->data)) != 0)
454 				goto error;
455 			skb_pull(skb, BR2684_PAD_LEN);
456 			skb->protocol = eth_type_trans(skb, net_dev);
457 		}
458 	}
459 
460 #ifdef CONFIG_ATM_BR2684_IPFILTER
461 	if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
462 		goto dropped;
463 #endif /* CONFIG_ATM_BR2684_IPFILTER */
464 	skb->dev = net_dev;
465 	ATM_SKB(skb)->vcc = atmvcc;	/* needed ? */
466 	pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
467 	skb_debug(skb);
468 	/* sigh, interface is down? */
469 	if (unlikely(!(net_dev->flags & IFF_UP)))
470 		goto dropped;
471 	net_dev->stats.rx_packets++;
472 	net_dev->stats.rx_bytes += skb->len;
473 	memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
474 	netif_rx(skb);
475 	return;
476 
477 dropped:
478 	net_dev->stats.rx_dropped++;
479 	goto free_skb;
480 error:
481 	net_dev->stats.rx_errors++;
482 free_skb:
483 	dev_kfree_skb(skb);
484 }
485 
486 /*
487  * Assign a vcc to a dev
488  * Note: we do not have explicit unassign, but look at _push()
489  */
490 static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
491 {
492 	struct sk_buff_head queue;
493 	int err;
494 	struct br2684_vcc *brvcc;
495 	struct sk_buff *skb, *tmp;
496 	struct sk_buff_head *rq;
497 	struct br2684_dev *brdev;
498 	struct net_device *net_dev;
499 	struct atm_backend_br2684 be;
500 	unsigned long flags;
501 
502 	if (copy_from_user(&be, arg, sizeof be))
503 		return -EFAULT;
504 	brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
505 	if (!brvcc)
506 		return -ENOMEM;
507 	write_lock_irq(&devs_lock);
508 	net_dev = br2684_find_dev(&be.ifspec);
509 	if (net_dev == NULL) {
510 		pr_err("tried to attach to non-existent device\n");
511 		err = -ENXIO;
512 		goto error;
513 	}
514 	brdev = BRPRIV(net_dev);
515 	if (atmvcc->push == NULL) {
516 		err = -EBADFD;
517 		goto error;
518 	}
519 	if (!list_empty(&brdev->brvccs)) {
520 		/* Only 1 VCC/dev right now */
521 		err = -EEXIST;
522 		goto error;
523 	}
524 	if (be.fcs_in != BR2684_FCSIN_NO ||
525 	    be.fcs_out != BR2684_FCSOUT_NO ||
526 	    be.fcs_auto || be.has_vpiid || be.send_padding ||
527 	    (be.encaps != BR2684_ENCAPS_VC &&
528 	     be.encaps != BR2684_ENCAPS_LLC) ||
529 	    be.min_size != 0) {
530 		err = -EINVAL;
531 		goto error;
532 	}
533 	pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
534 	if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
535 		unsigned char *esi = atmvcc->dev->esi;
536 		if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
537 			memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
538 		else
539 			net_dev->dev_addr[2] = 1;
540 	}
541 	list_add(&brvcc->brvccs, &brdev->brvccs);
542 	write_unlock_irq(&devs_lock);
543 	brvcc->device = net_dev;
544 	brvcc->atmvcc = atmvcc;
545 	atmvcc->user_back = brvcc;
546 	brvcc->encaps = (enum br2684_encaps)be.encaps;
547 	brvcc->old_push = atmvcc->push;
548 	brvcc->old_pop = atmvcc->pop;
549 	barrier();
550 	atmvcc->push = br2684_push;
551 	atmvcc->pop = br2684_pop;
552 
553 	__skb_queue_head_init(&queue);
554 	rq = &sk_atm(atmvcc)->sk_receive_queue;
555 
556 	spin_lock_irqsave(&rq->lock, flags);
557 	skb_queue_splice_init(rq, &queue);
558 	spin_unlock_irqrestore(&rq->lock, flags);
559 
560 	skb_queue_walk_safe(&queue, skb, tmp) {
561 		struct net_device *dev;
562 
563 		br2684_push(atmvcc, skb);
564 		dev = skb->dev;
565 
566 		dev->stats.rx_bytes -= skb->len;
567 		dev->stats.rx_packets--;
568 	}
569 
570 	/* initialize netdev carrier state */
571 	if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
572 		netif_carrier_off(net_dev);
573 	else
574 		netif_carrier_on(net_dev);
575 
576 	__module_get(THIS_MODULE);
577 	return 0;
578 
579 error:
580 	write_unlock_irq(&devs_lock);
581 	kfree(brvcc);
582 	return err;
583 }
584 
585 static const struct net_device_ops br2684_netdev_ops = {
586 	.ndo_start_xmit 	= br2684_start_xmit,
587 	.ndo_set_mac_address	= br2684_mac_addr,
588 	.ndo_change_mtu		= eth_change_mtu,
589 	.ndo_validate_addr	= eth_validate_addr,
590 };
591 
592 static const struct net_device_ops br2684_netdev_ops_routed = {
593 	.ndo_start_xmit 	= br2684_start_xmit,
594 	.ndo_set_mac_address	= br2684_mac_addr,
595 	.ndo_change_mtu		= eth_change_mtu
596 };
597 
598 static void br2684_setup(struct net_device *netdev)
599 {
600 	struct br2684_dev *brdev = BRPRIV(netdev);
601 
602 	ether_setup(netdev);
603 	brdev->net_dev = netdev;
604 
605 	netdev->netdev_ops = &br2684_netdev_ops;
606 
607 	INIT_LIST_HEAD(&brdev->brvccs);
608 }
609 
610 static void br2684_setup_routed(struct net_device *netdev)
611 {
612 	struct br2684_dev *brdev = BRPRIV(netdev);
613 
614 	brdev->net_dev = netdev;
615 	netdev->hard_header_len = 0;
616 	netdev->netdev_ops = &br2684_netdev_ops_routed;
617 	netdev->addr_len = 0;
618 	netdev->mtu = 1500;
619 	netdev->type = ARPHRD_PPP;
620 	netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
621 	netdev->tx_queue_len = 100;
622 	INIT_LIST_HEAD(&brdev->brvccs);
623 }
624 
625 static int br2684_create(void __user *arg)
626 {
627 	int err;
628 	struct net_device *netdev;
629 	struct br2684_dev *brdev;
630 	struct atm_newif_br2684 ni;
631 	enum br2684_payload payload;
632 
633 	pr_debug("\n");
634 
635 	if (copy_from_user(&ni, arg, sizeof ni))
636 		return -EFAULT;
637 
638 	if (ni.media & BR2684_FLAG_ROUTED)
639 		payload = p_routed;
640 	else
641 		payload = p_bridged;
642 	ni.media &= 0xffff;	/* strip flags */
643 
644 	if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
645 		return -EINVAL;
646 
647 	netdev = alloc_netdev(sizeof(struct br2684_dev),
648 			      ni.ifname[0] ? ni.ifname : "nas%d",
649 			      (payload == p_routed) ?
650 			      br2684_setup_routed : br2684_setup);
651 	if (!netdev)
652 		return -ENOMEM;
653 
654 	brdev = BRPRIV(netdev);
655 
656 	pr_debug("registered netdev %s\n", netdev->name);
657 	/* open, stop, do_ioctl ? */
658 	err = register_netdev(netdev);
659 	if (err < 0) {
660 		pr_err("register_netdev failed\n");
661 		free_netdev(netdev);
662 		return err;
663 	}
664 
665 	write_lock_irq(&devs_lock);
666 
667 	brdev->payload = payload;
668 
669 	if (list_empty(&br2684_devs)) {
670 		/* 1st br2684 device */
671 		brdev->number = 1;
672 	} else
673 		brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
674 
675 	list_add_tail(&brdev->br2684_devs, &br2684_devs);
676 	write_unlock_irq(&devs_lock);
677 	return 0;
678 }
679 
680 /*
681  * This handles ioctls actually performed on our vcc - we must return
682  * -ENOIOCTLCMD for any unrecognized ioctl
683  */
684 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
685 			unsigned long arg)
686 {
687 	struct atm_vcc *atmvcc = ATM_SD(sock);
688 	void __user *argp = (void __user *)arg;
689 	atm_backend_t b;
690 
691 	int err;
692 	switch (cmd) {
693 	case ATM_SETBACKEND:
694 	case ATM_NEWBACKENDIF:
695 		err = get_user(b, (atm_backend_t __user *) argp);
696 		if (err)
697 			return -EFAULT;
698 		if (b != ATM_BACKEND_BR2684)
699 			return -ENOIOCTLCMD;
700 		if (!capable(CAP_NET_ADMIN))
701 			return -EPERM;
702 		if (cmd == ATM_SETBACKEND)
703 			return br2684_regvcc(atmvcc, argp);
704 		else
705 			return br2684_create(argp);
706 #ifdef CONFIG_ATM_BR2684_IPFILTER
707 	case BR2684_SETFILT:
708 		if (atmvcc->push != br2684_push)
709 			return -ENOIOCTLCMD;
710 		if (!capable(CAP_NET_ADMIN))
711 			return -EPERM;
712 		err = br2684_setfilt(atmvcc, argp);
713 
714 		return err;
715 #endif /* CONFIG_ATM_BR2684_IPFILTER */
716 	}
717 	return -ENOIOCTLCMD;
718 }
719 
720 static struct atm_ioctl br2684_ioctl_ops = {
721 	.owner = THIS_MODULE,
722 	.ioctl = br2684_ioctl,
723 };
724 
725 #ifdef CONFIG_PROC_FS
726 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
727 	__acquires(devs_lock)
728 {
729 	read_lock(&devs_lock);
730 	return seq_list_start(&br2684_devs, *pos);
731 }
732 
733 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
734 {
735 	return seq_list_next(v, &br2684_devs, pos);
736 }
737 
738 static void br2684_seq_stop(struct seq_file *seq, void *v)
739 	__releases(devs_lock)
740 {
741 	read_unlock(&devs_lock);
742 }
743 
744 static int br2684_seq_show(struct seq_file *seq, void *v)
745 {
746 	const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
747 						    br2684_devs);
748 	const struct net_device *net_dev = brdev->net_dev;
749 	const struct br2684_vcc *brvcc;
750 
751 	seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
752 		   net_dev->name,
753 		   brdev->number,
754 		   net_dev->dev_addr,
755 		   brdev->mac_was_set ? "set" : "auto");
756 
757 	list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
758 		seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
759 			   ", failed copies %u/%u"
760 			   "\n", brvcc->atmvcc->dev->number,
761 			   brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
762 			   (brvcc->encaps == e_llc) ? "LLC" : "VC",
763 			   (brdev->payload == p_bridged) ? "bridged" : "routed",
764 			   brvcc->copies_failed, brvcc->copies_needed);
765 #ifdef CONFIG_ATM_BR2684_IPFILTER
766 #define b1(var, byte)	((u8 *) &brvcc->filter.var)[byte]
767 #define bs(var)		b1(var, 0), b1(var, 1), b1(var, 2), b1(var, 3)
768 		if (brvcc->filter.netmask != 0)
769 			seq_printf(seq, "    filter=%d.%d.%d.%d/"
770 				   "%d.%d.%d.%d\n", bs(prefix), bs(netmask));
771 #undef bs
772 #undef b1
773 #endif /* CONFIG_ATM_BR2684_IPFILTER */
774 	}
775 	return 0;
776 }
777 
778 static const struct seq_operations br2684_seq_ops = {
779 	.start = br2684_seq_start,
780 	.next = br2684_seq_next,
781 	.stop = br2684_seq_stop,
782 	.show = br2684_seq_show,
783 };
784 
785 static int br2684_proc_open(struct inode *inode, struct file *file)
786 {
787 	return seq_open(file, &br2684_seq_ops);
788 }
789 
790 static const struct file_operations br2684_proc_ops = {
791 	.owner = THIS_MODULE,
792 	.open = br2684_proc_open,
793 	.read = seq_read,
794 	.llseek = seq_lseek,
795 	.release = seq_release,
796 };
797 
798 extern struct proc_dir_entry *atm_proc_root;	/* from proc.c */
799 #endif /* CONFIG_PROC_FS */
800 
801 static int __init br2684_init(void)
802 {
803 #ifdef CONFIG_PROC_FS
804 	struct proc_dir_entry *p;
805 	p = proc_create("br2684", 0, atm_proc_root, &br2684_proc_ops);
806 	if (p == NULL)
807 		return -ENOMEM;
808 #endif
809 	register_atm_ioctl(&br2684_ioctl_ops);
810 	register_atmdevice_notifier(&atm_dev_notifier);
811 	return 0;
812 }
813 
814 static void __exit br2684_exit(void)
815 {
816 	struct net_device *net_dev;
817 	struct br2684_dev *brdev;
818 	struct br2684_vcc *brvcc;
819 	deregister_atm_ioctl(&br2684_ioctl_ops);
820 
821 #ifdef CONFIG_PROC_FS
822 	remove_proc_entry("br2684", atm_proc_root);
823 #endif
824 
825 
826 	unregister_atmdevice_notifier(&atm_dev_notifier);
827 
828 	while (!list_empty(&br2684_devs)) {
829 		net_dev = list_entry_brdev(br2684_devs.next);
830 		brdev = BRPRIV(net_dev);
831 		while (!list_empty(&brdev->brvccs)) {
832 			brvcc = list_entry_brvcc(brdev->brvccs.next);
833 			br2684_close_vcc(brvcc);
834 		}
835 
836 		list_del(&brdev->br2684_devs);
837 		unregister_netdev(net_dev);
838 		free_netdev(net_dev);
839 	}
840 }
841 
842 module_init(br2684_init);
843 module_exit(br2684_exit);
844 
845 MODULE_AUTHOR("Marcell GAL");
846 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
847 MODULE_LICENSE("GPL");
848