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
skb_debug(const struct sk_buff * skb)33 static 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
53 static const unsigned char ethertype_ipv4[] = { ETHERTYPE_IPV4 };
54 static const unsigned char ethertype_ipv6[] = { ETHERTYPE_IPV6 };
55 static const unsigned char llc_oui_pid_pad[] =
56 { LLC, SNAP_BRIDGED, PID_ETHERNET, PAD_BRIDGED };
57 static const unsigned char pad[] = { PAD_BRIDGED };
58 static const unsigned char llc_oui_ipv4[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV4 };
59 static const unsigned char llc_oui_ipv6[] = { LLC, SNAP_ROUTED, ETHERTYPE_IPV6 };
60
61 enum br2684_encaps {
62 e_vc = BR2684_ENCAPS_VC,
63 e_llc = BR2684_ENCAPS_LLC,
64 };
65
66 struct 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
83 struct 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 interrupt context, so write locking must block
97 * the current CPU's interrupts
98 */
99 static DEFINE_RWLOCK(devs_lock);
100
101 static LIST_HEAD(br2684_devs);
102
BRPRIV(const struct net_device * net_dev)103 static inline struct br2684_dev *BRPRIV(const struct net_device *net_dev)
104 {
105 return netdev_priv(net_dev);
106 }
107
list_entry_brdev(const struct list_head * le)108 static 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
BR2684_VCC(const struct atm_vcc * atmvcc)113 static inline struct br2684_vcc *BR2684_VCC(const struct atm_vcc *atmvcc)
114 {
115 return (struct br2684_vcc *)(atmvcc->user_back);
116 }
117
list_entry_brvcc(const struct list_head * le)118 static 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) */
br2684_find_dev(const struct br2684_if_spec * s)124 static 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
atm_dev_event(struct notifier_block * this,unsigned long event,void * arg)147 static 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
180 static 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 */
br2684_pop(struct atm_vcc * vcc,struct sk_buff * skb)185 static 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 */
br2684_xmit_vcc(struct sk_buff * skb,struct net_device * dev,struct br2684_vcc * brvcc)202 static 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
br2684_release_cb(struct atm_vcc * atmvcc)274 static 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
pick_outgoing_vcc(const struct sk_buff * skb,const struct br2684_dev * brdev)285 static 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
br2684_start_xmit(struct sk_buff * skb,struct net_device * dev)291 static 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 */
br2684_mac_addr(struct net_device * dev,void * p)350 static 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. */
br2684_setfilt(struct atm_vcc * atmvcc,void __user * arg)360 static 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 */
390 static inline int
packet_fails_filter(__be16 type,struct br2684_vcc * brvcc,struct sk_buff * skb)391 packet_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
br2684_close_vcc(struct br2684_vcc * brvcc)409 static 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: */
br2684_push(struct atm_vcc * atmvcc,struct sk_buff * skb)423 static 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
518 dropped:
519 net_dev->stats.rx_dropped++;
520 goto free_skb;
521 error:
522 net_dev->stats.rx_errors++;
523 free_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 */
br2684_regvcc(struct atm_vcc * atmvcc,void __user * arg)531 static 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 if (esi[0] | esi[1] | esi[2] | esi[3] | esi[4] | esi[5])
581 memcpy(net_dev->dev_addr, esi, net_dev->addr_len);
582 else
583 net_dev->dev_addr[2] = 1;
584 }
585 list_add(&brvcc->brvccs, &brdev->brvccs);
586 write_unlock_irq(&devs_lock);
587 brvcc->device = net_dev;
588 brvcc->atmvcc = atmvcc;
589 atmvcc->user_back = brvcc;
590 brvcc->encaps = (enum br2684_encaps)be.encaps;
591 brvcc->old_push = atmvcc->push;
592 brvcc->old_pop = atmvcc->pop;
593 brvcc->old_release_cb = atmvcc->release_cb;
594 brvcc->old_owner = atmvcc->owner;
595 barrier();
596 atmvcc->push = br2684_push;
597 atmvcc->pop = br2684_pop;
598 atmvcc->release_cb = br2684_release_cb;
599 atmvcc->owner = THIS_MODULE;
600
601 /* initialize netdev carrier state */
602 if (atmvcc->dev->signal == ATM_PHY_SIG_LOST)
603 netif_carrier_off(net_dev);
604 else
605 netif_carrier_on(net_dev);
606
607 __module_get(THIS_MODULE);
608
609 /* re-process everything received between connection setup and
610 backend setup */
611 vcc_process_recv_queue(atmvcc);
612 return 0;
613
614 error:
615 write_unlock_irq(&devs_lock);
616 kfree(brvcc);
617 return err;
618 }
619
620 static const struct net_device_ops br2684_netdev_ops = {
621 .ndo_start_xmit = br2684_start_xmit,
622 .ndo_set_mac_address = br2684_mac_addr,
623 .ndo_validate_addr = eth_validate_addr,
624 };
625
626 static const struct net_device_ops br2684_netdev_ops_routed = {
627 .ndo_start_xmit = br2684_start_xmit,
628 .ndo_set_mac_address = br2684_mac_addr,
629 };
630
br2684_setup(struct net_device * netdev)631 static void br2684_setup(struct net_device *netdev)
632 {
633 struct br2684_dev *brdev = BRPRIV(netdev);
634
635 ether_setup(netdev);
636 netdev->hard_header_len += sizeof(llc_oui_pid_pad); /* worst case */
637 brdev->net_dev = netdev;
638
639 netdev->netdev_ops = &br2684_netdev_ops;
640
641 INIT_LIST_HEAD(&brdev->brvccs);
642 }
643
br2684_setup_routed(struct net_device * netdev)644 static void br2684_setup_routed(struct net_device *netdev)
645 {
646 struct br2684_dev *brdev = BRPRIV(netdev);
647
648 brdev->net_dev = netdev;
649 netdev->hard_header_len = sizeof(llc_oui_ipv4); /* worst case */
650 netdev->netdev_ops = &br2684_netdev_ops_routed;
651 netdev->addr_len = 0;
652 netdev->mtu = ETH_DATA_LEN;
653 netdev->min_mtu = 0;
654 netdev->max_mtu = ETH_MAX_MTU;
655 netdev->type = ARPHRD_PPP;
656 netdev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
657 netdev->tx_queue_len = 100;
658 INIT_LIST_HEAD(&brdev->brvccs);
659 }
660
br2684_create(void __user * arg)661 static int br2684_create(void __user *arg)
662 {
663 int err;
664 struct net_device *netdev;
665 struct br2684_dev *brdev;
666 struct atm_newif_br2684 ni;
667 enum br2684_payload payload;
668
669 pr_debug("\n");
670
671 if (copy_from_user(&ni, arg, sizeof ni))
672 return -EFAULT;
673
674 if (ni.media & BR2684_FLAG_ROUTED)
675 payload = p_routed;
676 else
677 payload = p_bridged;
678 ni.media &= 0xffff; /* strip flags */
679
680 if (ni.media != BR2684_MEDIA_ETHERNET || ni.mtu != 1500)
681 return -EINVAL;
682
683 netdev = alloc_netdev(sizeof(struct br2684_dev),
684 ni.ifname[0] ? ni.ifname : "nas%d",
685 NET_NAME_UNKNOWN,
686 (payload == p_routed) ? br2684_setup_routed : br2684_setup);
687 if (!netdev)
688 return -ENOMEM;
689
690 brdev = BRPRIV(netdev);
691
692 pr_debug("registered netdev %s\n", netdev->name);
693 /* open, stop, do_ioctl ? */
694 err = register_netdev(netdev);
695 if (err < 0) {
696 pr_err("register_netdev failed\n");
697 free_netdev(netdev);
698 return err;
699 }
700
701 write_lock_irq(&devs_lock);
702
703 brdev->payload = payload;
704
705 if (list_empty(&br2684_devs)) {
706 /* 1st br2684 device */
707 brdev->number = 1;
708 } else
709 brdev->number = BRPRIV(list_entry_brdev(br2684_devs.prev))->number + 1;
710
711 list_add_tail(&brdev->br2684_devs, &br2684_devs);
712 write_unlock_irq(&devs_lock);
713 return 0;
714 }
715
716 /*
717 * This handles ioctls actually performed on our vcc - we must return
718 * -ENOIOCTLCMD for any unrecognized ioctl
719 */
br2684_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)720 static int br2684_ioctl(struct socket *sock, unsigned int cmd,
721 unsigned long arg)
722 {
723 struct atm_vcc *atmvcc = ATM_SD(sock);
724 void __user *argp = (void __user *)arg;
725 atm_backend_t b;
726
727 int err;
728 switch (cmd) {
729 case ATM_SETBACKEND:
730 case ATM_NEWBACKENDIF:
731 err = get_user(b, (atm_backend_t __user *) argp);
732 if (err)
733 return -EFAULT;
734 if (b != ATM_BACKEND_BR2684)
735 return -ENOIOCTLCMD;
736 if (!capable(CAP_NET_ADMIN))
737 return -EPERM;
738 if (cmd == ATM_SETBACKEND) {
739 if (sock->state != SS_CONNECTED)
740 return -EINVAL;
741 return br2684_regvcc(atmvcc, argp);
742 } else {
743 return br2684_create(argp);
744 }
745 #ifdef CONFIG_ATM_BR2684_IPFILTER
746 case BR2684_SETFILT:
747 if (atmvcc->push != br2684_push)
748 return -ENOIOCTLCMD;
749 if (!capable(CAP_NET_ADMIN))
750 return -EPERM;
751 err = br2684_setfilt(atmvcc, argp);
752
753 return err;
754 #endif /* CONFIG_ATM_BR2684_IPFILTER */
755 }
756 return -ENOIOCTLCMD;
757 }
758
759 static struct atm_ioctl br2684_ioctl_ops = {
760 .owner = THIS_MODULE,
761 .ioctl = br2684_ioctl,
762 };
763
764 #ifdef CONFIG_PROC_FS
br2684_seq_start(struct seq_file * seq,loff_t * pos)765 static void *br2684_seq_start(struct seq_file *seq, loff_t * pos)
766 __acquires(devs_lock)
767 {
768 read_lock(&devs_lock);
769 return seq_list_start(&br2684_devs, *pos);
770 }
771
br2684_seq_next(struct seq_file * seq,void * v,loff_t * pos)772 static void *br2684_seq_next(struct seq_file *seq, void *v, loff_t * pos)
773 {
774 return seq_list_next(v, &br2684_devs, pos);
775 }
776
br2684_seq_stop(struct seq_file * seq,void * v)777 static void br2684_seq_stop(struct seq_file *seq, void *v)
778 __releases(devs_lock)
779 {
780 read_unlock(&devs_lock);
781 }
782
br2684_seq_show(struct seq_file * seq,void * v)783 static int br2684_seq_show(struct seq_file *seq, void *v)
784 {
785 const struct br2684_dev *brdev = list_entry(v, struct br2684_dev,
786 br2684_devs);
787 const struct net_device *net_dev = brdev->net_dev;
788 const struct br2684_vcc *brvcc;
789
790 seq_printf(seq, "dev %.16s: num=%d, mac=%pM (%s)\n",
791 net_dev->name,
792 brdev->number,
793 net_dev->dev_addr,
794 brdev->mac_was_set ? "set" : "auto");
795
796 list_for_each_entry(brvcc, &brdev->brvccs, brvccs) {
797 seq_printf(seq, " vcc %d.%d.%d: encaps=%s payload=%s"
798 ", failed copies %u/%u"
799 "\n", brvcc->atmvcc->dev->number,
800 brvcc->atmvcc->vpi, brvcc->atmvcc->vci,
801 (brvcc->encaps == e_llc) ? "LLC" : "VC",
802 (brdev->payload == p_bridged) ? "bridged" : "routed",
803 brvcc->copies_failed, brvcc->copies_needed);
804 #ifdef CONFIG_ATM_BR2684_IPFILTER
805 if (brvcc->filter.netmask != 0)
806 seq_printf(seq, " filter=%pI4/%pI4\n",
807 &brvcc->filter.prefix,
808 &brvcc->filter.netmask);
809 #endif /* CONFIG_ATM_BR2684_IPFILTER */
810 }
811 return 0;
812 }
813
814 static const struct seq_operations br2684_seq_ops = {
815 .start = br2684_seq_start,
816 .next = br2684_seq_next,
817 .stop = br2684_seq_stop,
818 .show = br2684_seq_show,
819 };
820
821 extern struct proc_dir_entry *atm_proc_root; /* from proc.c */
822 #endif /* CONFIG_PROC_FS */
823
br2684_init(void)824 static int __init br2684_init(void)
825 {
826 #ifdef CONFIG_PROC_FS
827 struct proc_dir_entry *p;
828 p = proc_create_seq("br2684", 0, atm_proc_root, &br2684_seq_ops);
829 if (p == NULL)
830 return -ENOMEM;
831 #endif
832 register_atm_ioctl(&br2684_ioctl_ops);
833 register_atmdevice_notifier(&atm_dev_notifier);
834 return 0;
835 }
836
br2684_exit(void)837 static void __exit br2684_exit(void)
838 {
839 struct net_device *net_dev;
840 struct br2684_dev *brdev;
841 struct br2684_vcc *brvcc;
842 deregister_atm_ioctl(&br2684_ioctl_ops);
843
844 #ifdef CONFIG_PROC_FS
845 remove_proc_entry("br2684", atm_proc_root);
846 #endif
847
848
849 unregister_atmdevice_notifier(&atm_dev_notifier);
850
851 while (!list_empty(&br2684_devs)) {
852 net_dev = list_entry_brdev(br2684_devs.next);
853 brdev = BRPRIV(net_dev);
854 while (!list_empty(&brdev->brvccs)) {
855 brvcc = list_entry_brvcc(brdev->brvccs.next);
856 br2684_close_vcc(brvcc);
857 }
858
859 list_del(&brdev->br2684_devs);
860 unregister_netdev(net_dev);
861 free_netdev(net_dev);
862 }
863 }
864
865 module_init(br2684_init);
866 module_exit(br2684_exit);
867
868 MODULE_AUTHOR("Marcell GAL");
869 MODULE_DESCRIPTION("RFC2684 bridged protocols over ATM/AAL5");
870 MODULE_LICENSE("GPL");
871