1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Ethernet netdevice using ATM AAL5 as underlying carrier
4 * (RFC1483 obsoleted by RFC2684) for Linux
5 *
6 * Authors: Marcell GAL, 2000, XDSL Ltd, Hungary
7 *          Eric Kinzie, 2006-2007, US Naval Research Laboratory
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
11
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/list.h>
16#include <linux/netdevice.h>
17#include <linux/skbuff.h>
18#include <linux/etherdevice.h>
19#include <linux/rtnetlink.h>
20#include <linux/ip.h>
21#include <linux/uaccess.h>
22#include <linux/slab.h>
23#include <net/arp.h>
24#include <linux/atm.h>
25#include <linux/atmdev.h>
26#include <linux/capability.h>
27#include <linux/seq_file.h>
28
29#include <linux/atmbr2684.h>
30
31#include "common.h"
32
33static void skb_debug(const struct sk_buff *skb)
34{
35#ifdef SKB_DEBUG
36#define NUM2PRINT 50
37	print_hex_dump(KERN_DEBUG, "br2684: skb: ", DUMP_OFFSET,
38		       16, 1, skb->data, min(NUM2PRINT, skb->len), true);
39#endif
40}
41
42#define BR2684_ETHERTYPE_LEN	2
43#define BR2684_PAD_LEN		2
44
45#define LLC		0xaa, 0xaa, 0x03
46#define SNAP_BRIDGED	0x00, 0x80, 0xc2
47#define SNAP_ROUTED	0x00, 0x00, 0x00
48#define PID_ETHERNET	0x00, 0x07
49#define ETHERTYPE_IPV4	0x08, 0x00
50#define ETHERTYPE_IPV6	0x86, 0xdd
51#define PAD_BRIDGED	0x00, 0x00
52
53static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
54static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
55static const unsigned char llc_oui_pid_pad[] =
56			{ LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
57static const unsigned char pad[] = { PAD_BRIDGED };
58static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
59static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
60
61enum br2684_encaps {
62	e_vc = BR2684_ENCAPS_VC,
63	e_llc = BR2684_ENCAPS_LLC,
64};
65
66struct br2684_vcc {
67	struct atm_vcc *atmvcc;
68	struct net_device *device;
69	/* keep old push, pop functions for chaining */
70	void (*old_push)(struct atm_vcc *vcc, struct sk_buff *skb);
71	void (*old_pop)(struct atm_vcc *vcc, struct sk_buff *skb);
72	void (*old_release_cb)(struct atm_vcc *vcc);
73	struct module *old_owner;
74	enum br2684_encaps encaps;
75	struct list_head brvccs;
76#ifdef CONFIG_ATM_BR2684_IPFILTER
77	struct br2684_filter filter;
78#endif /* CONFIG_ATM_BR2684_IPFILTER */
79	unsigned int copies_needed, copies_failed;
80	atomic_t qspace;
81};
82
83struct br2684_dev {
84	struct net_device *net_dev;
85	struct list_head br2684_devs;
86	int number;
87	struct list_head brvccs;	/* one device <=> one vcc (before xmas) */
88	int mac_was_set;
89	enum br2684_payload payload;
90};
91
92/*
93 * This lock should be held for writing any time the list of devices or
94 * their attached vcc's could be altered.  It should be held for reading
95 * any time these are being queried.  Note that we sometimes need to
96 * do read-locking under interrupting context, so write locking must block
97 * the current CPU's interrupts.
98 */
99static DEFINE_RWLOCK(devs_lock);
100
101static LIST_HEAD(br2684_devs);
102
103static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
104{
105	return netdev_priv(net_dev);
106}
107
108static inline struct net_device *list_entry_brdev(const struct list_head *le)
109{
110	return list_entry(le, struct br2684_dev, br2684_devs)->net_dev;
111}
112
113static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
114{
115	return (struct br2684_vcc *)(atmvcc->user_back);
116}
117
118static inline struct br2684_vcc *list_entry_brvcc(const struct list_head *le)
119{
120	return list_entry(le, struct br2684_vcc, brvccs);
121}
122
123/* Caller should hold read_lock(&devs_lock) */
124static struct net_device *br2684_find_dev(const struct br2684_if_spec *s)
125{
126	struct list_head *lh;
127	struct net_device *net_dev;
128	switch (s->method) {
129	case BR2684_FIND_BYNUM:
130		list_for_each(lh, &br2684_devs) {
131			net_dev = list_entry_brdev(lh);
132			if (BRPRIV(net_dev)->number == s->spec.devnum)
133				return net_dev;
134		}
135		break;
136	case BR2684_FIND_BYIFNAME:
137		list_for_each(lh, &br2684_devs) {
138			net_dev = list_entry_brdev(lh);
139			if (!strncmp(net_dev->name, s->spec.ifname, IFNAMSIZ))
140				return net_dev;
141		}
142		break;
143	}
144	return NULL;
145}
146
147static int atm_dev_event(struct notifier_block *this, unsigned long event,
148		 void *arg)
149{
150	struct atm_dev *atm_dev = arg;
151	struct list_head *lh;
152	struct net_device *net_dev;
153	struct br2684_vcc *brvcc;
154	struct atm_vcc *atm_vcc;
155	unsigned long flags;
156
157	pr_debug("event=%ld dev=%p\n", event, atm_dev);
158
159	read_lock_irqsave(&devs_lock, flags);
160	list_for_each(lh, &br2684_devs) {
161		net_dev = list_entry_brdev(lh);
162
163		list_for_each_entry(brvcc, &BRPRIV(net_dev)->brvccs, brvccs) {
164			atm_vcc = brvcc->atmvcc;
165			if (atm_vcc && brvcc->atmvcc->dev == atm_dev) {
166
167				if (atm_vcc->dev->signal == ATM_PHY_SIG_LOST)
168					netif_carrier_off(net_dev);
169				else
170					netif_carrier_on(net_dev);
171
172			}
173		}
174	}
175	read_unlock_irqrestore(&devs_lock, flags);
176
177	return NOTIFY_DONE;
178}
179
180static struct notifier_block atm_dev_notifier = {
181	.notifier_call = atm_dev_event,
182};
183
184/* chained vcc->pop function.  Check if we should wake the netif_queue */
185static void br2684_pop(struct atm_vcc *vcc, struct sk_buff *skb)
186{
187	struct br2684_vcc *brvcc = BR2684_VCC(vcc);
188
189	pr_debug("(vcc %p ; net_dev %p )\n", vcc, brvcc->device);
190	brvcc->old_pop(vcc, skb);
191
192	/* If the queue space just went up from zero, wake */
193	if (atomic_inc_return(&brvcc->qspace) == 1)
194		netif_wake_queue(brvcc->device);
195}
196
197/*
198 * Send a packet out a particular vcc.  Not to useful right now, but paves
199 * the way for multiple vcc's per itf.  Returns true if we can send,
200 * otherwise false
201 */
202static int br2684_xmit_vcc(struct sk_buff *skb, struct net_device *dev,
203			   struct br2684_vcc *brvcc)
204{
205	struct br2684_dev *brdev = BRPRIV(dev);
206	struct atm_vcc *atmvcc;
207	int minheadroom = (brvcc->encaps == e_llc) ?
208		((brdev->payload == p_bridged) ?
209			sizeof(llc_oui_pid_pad) : sizeof(llc_oui_ipv4)) :
210		((brdev->payload == p_bridged) ? BR2684_PAD_LEN : 0);
211
212	if (skb_headroom(skb) < minheadroom) {
213		struct sk_buff *skb2 = skb_realloc_headroom(skb, minheadroom);
214		brvcc->copies_needed++;
215		dev_kfree_skb(skb);
216		if (skb2 == NULL) {
217			brvcc->copies_failed++;
218			return 0;
219		}
220		skb = skb2;
221	}
222
223	if (brvcc->encaps == e_llc) {
224		if (brdev->payload == p_bridged) {
225			skb_push(skb, sizeof(llc_oui_pid_pad));
226			skb_copy_to_linear_data(skb, llc_oui_pid_pad,
227						sizeof(llc_oui_pid_pad));
228		} else if (brdev->payload == p_routed) {
229			unsigned short prot = ntohs(skb->protocol);
230
231			skb_push(skb, sizeof(llc_oui_ipv4));
232			switch (prot) {
233			case ETH_P_IP:
234				skb_copy_to_linear_data(skb, llc_oui_ipv4,
235							sizeof(llc_oui_ipv4));
236				break;
237			case ETH_P_IPV6:
238				skb_copy_to_linear_data(skb, llc_oui_ipv6,
239							sizeof(llc_oui_ipv6));
240				break;
241			default:
242				dev_kfree_skb(skb);
243				return 0;
244			}
245		}
246	} else { /* e_vc */
247		if (brdev->payload == p_bridged) {
248			skb_push(skb, 2);
249			memset(skb->data, 0, 2);
250		}
251	}
252	skb_debug(skb);
253
254	ATM_SKB(skb)->vcc = atmvcc = brvcc->atmvcc;
255	pr_debug("atm_skb(%p)->vcc(%p)->dev(%p)\n", skb, atmvcc, atmvcc->dev);
256	atm_account_tx(atmvcc, skb);
257	dev->stats.tx_packets++;
258	dev->stats.tx_bytes += skb->len;
259
260	if (atomic_dec_return(&brvcc->qspace) < 1) {
261		/* No more please! */
262		netif_stop_queue(brvcc->device);
263		/* We might have raced with br2684_pop() */
264		if (unlikely(atomic_read(&brvcc->qspace) > 0))
265			netif_wake_queue(brvcc->device);
266	}
267
268	/* If this fails immediately, the skb will be freed and br2684_pop()
269	   will wake the queue if appropriate. Just return an error so that
270	   the stats are updated correctly */
271	return !atmvcc->send(atmvcc, skb);
272}
273
274static void br2684_release_cb(struct atm_vcc *atmvcc)
275{
276	struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
277
278	if (atomic_read(&brvcc->qspace) > 0)
279		netif_wake_queue(brvcc->device);
280
281	if (brvcc->old_release_cb)
282		brvcc->old_release_cb(atmvcc);
283}
284
285static inline struct br2684_vcc *pick_outgoing_vcc(const struct sk_buff *skb,
286						   const struct br2684_dev *brdev)
287{
288	return list_empty(&brdev->brvccs) ? NULL : list_entry_brvcc(brdev->brvccs.next);	/* 1 vcc/dev right now */
289}
290
291static netdev_tx_t br2684_start_xmit(struct sk_buff *skb,
292				     struct net_device *dev)
293{
294	struct br2684_dev *brdev = BRPRIV(dev);
295	struct br2684_vcc *brvcc;
296	struct atm_vcc *atmvcc;
297	netdev_tx_t ret = NETDEV_TX_OK;
298
299	pr_debug("skb_dst(skb)=%p\n", skb_dst(skb));
300	read_lock(&devs_lock);
301	brvcc = pick_outgoing_vcc(skb, brdev);
302	if (brvcc == NULL) {
303		pr_debug("no vcc attached to dev %s\n", dev->name);
304		dev->stats.tx_errors++;
305		dev->stats.tx_carrier_errors++;
306		/* netif_stop_queue(dev); */
307		dev_kfree_skb(skb);
308		goto out_devs;
309	}
310	atmvcc = brvcc->atmvcc;
311
312	bh_lock_sock(sk_atm(atmvcc));
313
314	if (test_bit(ATM_VF_RELEASED, &atmvcc->flags) ||
315	    test_bit(ATM_VF_CLOSE, &atmvcc->flags) ||
316	    !test_bit(ATM_VF_READY, &atmvcc->flags)) {
317		dev->stats.tx_dropped++;
318		dev_kfree_skb(skb);
319		goto out;
320	}
321
322	if (sock_owned_by_user(sk_atm(atmvcc))) {
323		netif_stop_queue(brvcc->device);
324		ret = NETDEV_TX_BUSY;
325		goto out;
326	}
327
328	if (!br2684_xmit_vcc(skb, dev, brvcc)) {
329		/*
330		 * We should probably use netif_*_queue() here, but that
331		 * involves added complication.  We need to walk before
332		 * we can run.
333		 *
334		 * Don't free here! this pointer might be no longer valid!
335		 */
336		dev->stats.tx_errors++;
337		dev->stats.tx_fifo_errors++;
338	}
339 out:
340	bh_unlock_sock(sk_atm(atmvcc));
341 out_devs:
342	read_unlock(&devs_lock);
343	return ret;
344}
345
346/*
347 * We remember when the MAC gets set, so we don't override it later with
348 * the ESI of the ATM card of the first VC
349 */
350static int br2684_mac_addr(struct net_device *dev, void *p)
351{
352	int err = eth_mac_addr(dev, p);
353	if (!err)
354		BRPRIV(dev)->mac_was_set = 1;
355	return err;
356}
357
358#ifdef CONFIG_ATM_BR2684_IPFILTER
359/* this IOCTL is experimental. */
360static int br2684_setfilt(struct atm_vcc *atmvcc, void __user * arg)
361{
362	struct br2684_vcc *brvcc;
363	struct br2684_filter_set fs;
364
365	if (copy_from_user(&fs, arg, sizeof fs))
366		return -EFAULT;
367	if (fs.ifspec.method != BR2684_FIND_BYNOTHING) {
368		/*
369		 * This is really a per-vcc thing, but we can also search
370		 * by device.
371		 */
372		struct br2684_dev *brdev;
373		read_lock(&devs_lock);
374		brdev = BRPRIV(br2684_find_dev(&fs.ifspec));
375		if (brdev == NULL || list_empty(&brdev->brvccs) ||
376		    brdev->brvccs.next != brdev->brvccs.prev)	/* >1 VCC */
377			brvcc = NULL;
378		else
379			brvcc = list_entry_brvcc(brdev->brvccs.next);
380		read_unlock(&devs_lock);
381		if (brvcc == NULL)
382			return -ESRCH;
383	} else
384		brvcc = BR2684_VCC(atmvcc);
385	memcpy(&brvcc->filter, &fs.filter, sizeof(brvcc->filter));
386	return 0;
387}
388
389/* Returns 1 if packet should be dropped */
390static inline int
391packet_fails_filter(__be16 type, struct br2684_vcc *brvcc, struct sk_buff *skb)
392{
393	if (brvcc->filter.netmask == 0)
394		return 0;	/* no filter in place */
395	if (type == htons(ETH_P_IP) &&
396	    (((struct iphdr *)(skb->data))->daddr & brvcc->filter.
397	     netmask) == brvcc->filter.prefix)
398		return 0;
399	if (type == htons(ETH_P_ARP))
400		return 0;
401	/*
402	 * TODO: we should probably filter ARPs too.. don't want to have
403	 * them returning values that don't make sense, or is that ok?
404	 */
405	return 1;		/* drop */
406}
407#endif /* CONFIG_ATM_BR2684_IPFILTER */
408
409static void br2684_close_vcc(struct br2684_vcc *brvcc)
410{
411	pr_debug("removing VCC %p from dev %p\n", brvcc, brvcc->device);
412	write_lock_irq(&devs_lock);
413	list_del(&brvcc->brvccs);
414	write_unlock_irq(&devs_lock);
415	brvcc->atmvcc->user_back = NULL;	/* what about vcc->recvq ??? */
416	brvcc->atmvcc->release_cb = brvcc->old_release_cb;
417	brvcc->old_push(brvcc->atmvcc, NULL);	/* pass on the bad news */
418	module_put(brvcc->old_owner);
419	kfree(brvcc);
420}
421
422/* when AAL5 PDU comes in: */
423static void br2684_push(struct atm_vcc *atmvcc, struct sk_buff *skb)
424{
425	struct br2684_vcc *brvcc = BR2684_VCC(atmvcc);
426	struct net_device *net_dev = brvcc->device;
427	struct br2684_dev *brdev = BRPRIV(net_dev);
428
429	pr_debug("\n");
430
431	if (unlikely(skb == NULL)) {
432		/* skb==NULL means VCC is being destroyed */
433		br2684_close_vcc(brvcc);
434		if (list_empty(&brdev->brvccs)) {
435			write_lock_irq(&devs_lock);
436			list_del(&brdev->br2684_devs);
437			write_unlock_irq(&devs_lock);
438			unregister_netdev(net_dev);
439			free_netdev(net_dev);
440		}
441		return;
442	}
443
444	skb_debug(skb);
445	atm_return(atmvcc, skb->truesize);
446	pr_debug("skb from brdev %p\n", brdev);
447	if (brvcc->encaps == e_llc) {
448
449		if (skb->len > 7 && skb->data[7] == 0x01)
450			__skb_trim(skb, skb->len - 4);
451
452		/* accept packets that have "ipv[46]" in the snap header */
453		if ((skb->len >= (sizeof(llc_oui_ipv4))) &&
454		    (memcmp(skb->data, llc_oui_ipv4,
455			    sizeof(llc_oui_ipv4) - BR2684_ETHERTYPE_LEN) == 0)) {
456			if (memcmp(skb->data + 6, ethertype_ipv6,
457				   sizeof(ethertype_ipv6)) == 0)
458				skb->protocol = htons(ETH_P_IPV6);
459			else if (memcmp(skb->data + 6, ethertype_ipv4,
460					sizeof(ethertype_ipv4)) == 0)
461				skb->protocol = htons(ETH_P_IP);
462			else
463				goto error;
464			skb_pull(skb, sizeof(llc_oui_ipv4));
465			skb_reset_network_header(skb);
466			skb->pkt_type = PACKET_HOST;
467		/*
468		 * Let us waste some time for checking the encapsulation.
469		 * Note, that only 7 char is checked so frames with a valid FCS
470		 * are also accepted (but FCS is not checked of course).
471		 */
472		} else if ((skb->len >= sizeof(llc_oui_pid_pad)) &&
473			   (memcmp(skb->data, llc_oui_pid_pad, 7) == 0)) {
474			skb_pull(skb, sizeof(llc_oui_pid_pad));
475			skb->protocol = eth_type_trans(skb, net_dev);
476		} else
477			goto error;
478
479	} else { /* e_vc */
480		if (brdev->payload == p_routed) {
481			struct iphdr *iph;
482
483			skb_reset_network_header(skb);
484			iph = ip_hdr(skb);
485			if (iph->version == 4)
486				skb->protocol = htons(ETH_P_IP);
487			else if (iph->version == 6)
488				skb->protocol = htons(ETH_P_IPV6);
489			else
490				goto error;
491			skb->pkt_type = PACKET_HOST;
492		} else { /* p_bridged */
493			/* first 2 chars should be 0 */
494			if (memcmp(skb->data, pad, BR2684_PAD_LEN) != 0)
495				goto error;
496			skb_pull(skb, BR2684_PAD_LEN);
497			skb->protocol = eth_type_trans(skb, net_dev);
498		}
499	}
500
501#ifdef CONFIG_ATM_BR2684_IPFILTER
502	if (unlikely(packet_fails_filter(skb->protocol, brvcc, skb)))
503		goto dropped;
504#endif /* CONFIG_ATM_BR2684_IPFILTER */
505	skb->dev = net_dev;
506	ATM_SKB(skb)->vcc = atmvcc;	/* needed ? */
507	pr_debug("received packet's protocol: %x\n", ntohs(skb->protocol));
508	skb_debug(skb);
509	/* sigh, interface is down? */
510	if (unlikely(!(net_dev->flags & IFF_UP)))
511		goto dropped;
512	net_dev->stats.rx_packets++;
513	net_dev->stats.rx_bytes += skb->len;
514	memset(ATM_SKB(skb), 0, sizeof(struct atm_skb_data));
515	netif_rx(skb);
516	return;
517
518dropped:
519	net_dev->stats.rx_dropped++;
520	goto free_skb;
521error:
522	net_dev->stats.rx_errors++;
523free_skb:
524	dev_kfree_skb(skb);
525}
526
527/*
528 * Assign a vcc to a dev
529 * Note: we do not have explicit unassign, but look at _push()
530 */
531static int br2684_regvcc(struct atm_vcc *atmvcc, void __user * arg)
532{
533	struct br2684_vcc *brvcc;
534	struct br2684_dev *brdev;
535	struct net_device *net_dev;
536	struct atm_backend_br2684 be;
537	int err;
538
539	if (copy_from_user(&be, arg, sizeof be))
540		return -EFAULT;
541	brvcc = kzalloc(sizeof(struct br2684_vcc), GFP_KERNEL);
542	if (!brvcc)
543		return -ENOMEM;
544	/*
545	 * Allow two packets in the ATM queue. One actually being sent, and one
546	 * for the ATM 'TX done' handler to send. It shouldn't take long to get
547	 * the next one from the netdev queue, when we need it. More than that
548	 * would be bufferbloat.
549	 */
550	atomic_set(&brvcc->qspace, 2);
551	write_lock_irq(&devs_lock);
552	net_dev = br2684_find_dev(&be.ifspec);
553	if (net_dev == NULL) {
554		pr_err("tried to attach to non-existent device\n");
555		err = -ENXIO;
556		goto error;
557	}
558	brdev = BRPRIV(net_dev);
559	if (atmvcc->push == NULL) {
560		err = -EBADFD;
561		goto error;
562	}
563	if (!list_empty(&brdev->brvccs)) {
564		/* Only 1 VCC/dev right now */
565		err = -EEXIST;
566		goto error;
567	}
568	if (be.fcs_in != BR2684_FCSIN_NO ||
569	    be.fcs_out != BR2684_FCSOUT_NO ||
570	    be.fcs_auto || be.has_vpiid || be.send_padding ||
571	    (be.encaps != BR2684_ENCAPS_VC &&
572	     be.encaps != BR2684_ENCAPS_LLC) ||
573	    be.min_size != 0) {
574		err = -EINVAL;
575		goto error;
576	}
577	pr_debug("vcc=%p, encaps=%d, brvcc=%p\n", atmvcc, be.encaps, brvcc);
578	if (list_empty(&brdev->brvccs) && !brdev->mac_was_set) {
579		unsigned char *esi = atmvcc->dev->esi;
580		const u8 one = 1;
581
582		if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
583			dev_addr_set(net_dev, esi);
584		else
585			dev_addr_mod(net_dev, 2, &one, 1);
586	}
587	list_add(&brvcc->brvccs, &brdev->brvccs);
588	write_unlock_irq(&devs_lock);
589	brvcc->device = net_dev;
590	brvcc->atmvcc = atmvcc;
591	atmvcc->user_back = brvcc;
592	brvcc->encaps = (enum br2684_encaps)be.encaps;
593	brvcc->old_push = atmvcc->push;
594	brvcc->old_pop = atmvcc->pop;
595	brvcc->old_release_cb = atmvcc->release_cb;
596	brvcc->old_owner = atmvcc->owner;
597	barrier();
598	atmvcc->push = br2684_push;
599	atmvcc->pop = br2684_pop;
600	atmvcc->release_cb = br2684_release_cb;
601	atmvcc->owner = THIS_MODULE;
602
603	/* initialize netdev carrier state */
604	if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
605		netif_carrier_off(net_dev);
606	else
607		netif_carrier_on(net_dev);
608
609	__module_get(THIS_MODULE);
610
611	/* re-process everything received between connection setup and
612	   backend setup */
613	vcc_process_recv_queue(atmvcc);
614	return 0;
615
616error:
617	write_unlock_irq(&devs_lock);
618	kfree(brvcc);
619	return err;
620}
621
622static const struct net_device_ops br2684_netdev_ops = {
623	.ndo_start_xmit 	= br2684_start_xmit,
624	.ndo_set_mac_address	= br2684_mac_addr,
625	.ndo_validate_addr	= eth_validate_addr,
626};
627
628static const struct net_device_ops br2684_netdev_ops_routed = {
629	.ndo_start_xmit 	= br2684_start_xmit,
630	.ndo_set_mac_address	= br2684_mac_addr,
631};
632
633static void br2684_setup(struct net_device *netdev)
634{
635	struct br2684_dev *brdev = BRPRIV(netdev);
636
637	ether_setup(netdev);
638	netdev->hard_header_len += sizeof(llc_oui_pid_pad); /* worst case */
639	brdev->net_dev = netdev;
640
641	netdev->netdev_ops = &br2684_netdev_ops;
642
643	INIT_LIST_HEAD(&brdev->brvccs);
644}
645
646static void br2684_setup_routed(struct net_device *netdev)
647{
648	struct br2684_dev *brdev = BRPRIV(netdev);
649
650	brdev->net_dev = netdev;
651	netdev->hard_header_len = sizeof(llc_oui_ipv4); /* worst case */
652	netdev->netdev_ops = &br2684_netdev_ops_routed;
653	netdev->addr_len = 0;
654	netdev->mtu = ETH_DATA_LEN;
655	netdev->min_mtu = 0;
656	netdev->max_mtu = ETH_MAX_MTU;
657	netdev->type = ARPHRD_PPP;
658	netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
659	netdev->tx_queue_len = 100;
660	INIT_LIST_HEAD(&brdev->brvccs);
661}
662
663static int br2684_create(void __user *arg)
664{
665	int err;
666	struct net_device *netdev;
667	struct br2684_dev *brdev;
668	struct atm_newif_br2684 ni;
669	enum br2684_payload payload;
670
671	pr_debug("\n");
672
673	if (copy_from_user(&ni, arg, sizeof ni))
674		return -EFAULT;
675
676	if (ni.media & BR2684_FLAG_ROUTED)
677		payload = p_routed;
678	else
679		payload = p_bridged;
680	ni.media &= 0xffff;	/* strip flags */
681
682	if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
683		return -EINVAL;
684
685	netdev = alloc_netdev(sizeof(struct br2684_dev),
686			      ni.ifname[0] ? ni.ifname : "nas%d",
687			      NET_NAME_UNKNOWN,
688			      (payload == p_routed) ? br2684_setup_routed : br2684_setup);
689	if (!netdev)
690		return -ENOMEM;
691
692	brdev = BRPRIV(netdev);
693
694	pr_debug("registered netdev %s\n", netdev->name);
695	/* open, stop, do_ioctl ? */
696	err = register_netdev(netdev);
697	if (err < 0) {
698		pr_err("register_netdev failed\n");
699		free_netdev(netdev);
700		return err;
701	}
702
703	write_lock_irq(&devs_lock);
704
705	brdev->payload = payload;
706
707	if (list_empty(&br2684_devs)) {
708		/* 1st br2684 device */
709		brdev->number = 1;
710	} else
711		brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
712
713	list_add_tail(&brdev->br2684_devs, &br2684_devs);
714	write_unlock_irq(&devs_lock);
715	return 0;
716}
717
718/*
719 * This handles ioctls actually performed on our vcc - we must return
720 * -ENOIOCTLCMD for any unrecognized ioctl
721 */
722static int br2684_ioctl(struct socket *sock, unsigned int cmd,
723			unsigned long arg)
724{
725	struct atm_vcc *atmvcc = ATM_SD(sock);
726	void __user *argp = (void __user *)arg;
727	atm_backend_t b;
728
729	int err;
730	switch (cmd) {
731	case ATM_SETBACKEND:
732	case ATM_NEWBACKENDIF:
733		err = get_user(b, (atm_backend_t __user *) argp);
734		if (err)
735			return -EFAULT;
736		if (b != ATM_BACKEND_BR2684)
737			return -ENOIOCTLCMD;
738		if (!capable(CAP_NET_ADMIN))
739			return -EPERM;
740		if (cmd == ATM_SETBACKEND) {
741			if (sock->state != SS_CONNECTED)
742				return -EINVAL;
743			return br2684_regvcc(atmvcc, argp);
744		} else {
745			return br2684_create(argp);
746		}
747#ifdef CONFIG_ATM_BR2684_IPFILTER
748	case BR2684_SETFILT:
749		if (atmvcc->push != br2684_push)
750			return -ENOIOCTLCMD;
751		if (!capable(CAP_NET_ADMIN))
752			return -EPERM;
753		err = br2684_setfilt(atmvcc, argp);
754
755		return err;
756#endif /* CONFIG_ATM_BR2684_IPFILTER */
757	}
758	return -ENOIOCTLCMD;
759}
760
761static struct atm_ioctl br2684_ioctl_ops = {
762	.owner = THIS_MODULE,
763	.ioctl = br2684_ioctl,
764};
765
766#ifdef CONFIG_PROC_FS
767static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
768	__acquires(devs_lock)
769{
770	read_lock(&devs_lock);
771	return seq_list_start(&br2684_devs, *pos);
772}
773
774static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
775{
776	return seq_list_next(v, &br2684_devs, pos);
777}
778
779static void br2684_seq_stop(struct seq_file *seq, void *v)
780	__releases(devs_lock)
781{
782	read_unlock(&devs_lock);
783}
784
785static int br2684_seq_show(struct seq_file *seq, void *v)
786{
787	const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
788						    br2684_devs);
789	const struct net_device *net_dev = brdev->net_dev;
790	const struct br2684_vcc *brvcc;
791
792	seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
793		   net_dev->name,
794		   brdev->number,
795		   net_dev->dev_addr,
796		   brdev->mac_was_set ? "set" : "auto");
797
798	list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
799		seq_printf(seq, "  vcc %d.%d.%d: encaps=%s payload=%s"
800			   ", failed copies %u/%u"
801			   "\n", brvcc->atmvcc->dev->number,
802			   brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
803			   (brvcc->encaps == e_llc) ? "LLC" : "VC",
804			   (brdev->payload == p_bridged) ? "bridged" : "routed",
805			   brvcc->copies_failed, brvcc->copies_needed);
806#ifdef CONFIG_ATM_BR2684_IPFILTER
807		if (brvcc->filter.netmask != 0)
808			seq_printf(seq, "    filter=%pI4/%pI4\n",
809				   &brvcc->filter.prefix,
810				   &brvcc->filter.netmask);
811#endif /* CONFIG_ATM_BR2684_IPFILTER */
812	}
813	return 0;
814}
815
816static const struct seq_operations br2684_seq_ops = {
817	.start = br2684_seq_start,
818	.next = br2684_seq_next,
819	.stop = br2684_seq_stop,
820	.show = br2684_seq_show,
821};
822
823extern struct proc_dir_entry *atm_proc_root;	/* from proc.c */
824#endif /* CONFIG_PROC_FS */
825
826static int __init br2684_init(void)
827{
828#ifdef CONFIG_PROC_FS
829	struct proc_dir_entry *p;
830	p = proc_create_seq("br2684", 0, atm_proc_root, &br2684_seq_ops);
831	if (p == NULL)
832		return -ENOMEM;
833#endif
834	register_atm_ioctl(&br2684_ioctl_ops);
835	register_atmdevice_notifier(&atm_dev_notifier);
836	return 0;
837}
838
839static void __exit br2684_exit(void)
840{
841	struct net_device *net_dev;
842	struct br2684_dev *brdev;
843	struct br2684_vcc *brvcc;
844	deregister_atm_ioctl(&br2684_ioctl_ops);
845
846#ifdef CONFIG_PROC_FS
847	remove_proc_entry("br2684", atm_proc_root);
848#endif
849
850
851	unregister_atmdevice_notifier(&atm_dev_notifier);
852
853	while (!list_empty(&br2684_devs)) {
854		net_dev = list_entry_brdev(br2684_devs.next);
855		brdev = BRPRIV(net_dev);
856		while (!list_empty(&brdev->brvccs)) {
857			brvcc = list_entry_brvcc(brdev->brvccs.next);
858			br2684_close_vcc(brvcc);
859		}
860
861		list_del(&brdev->br2684_devs);
862		unregister_netdev(net_dev);
863		free_netdev(net_dev);
864	}
865}
866
867module_init(br2684_init);
868module_exit(br2684_exit);
869
870MODULE_AUTHOR("Marcell GAL");
871MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
872MODULE_LICENSE("GPL");
873