1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Generic HDLC support routines for Linux
4 * Frame Relay support
5 *
6 * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
7 *
8
9 Theory of PVC state
10
11 DCE mode:
12
13 (exist,new) -> 0,0 when "PVC create" or if "link unreliable"
14 0,x -> 1,1 if "link reliable" when sending FULL STATUS
15 1,1 -> 1,0 if received FULL STATUS ACK
16
17 (active) -> 0 when "ifconfig PVC down" or "link unreliable" or "PVC create"
18 -> 1 when "PVC up" and (exist,new) = 1,0
19
20 DTE mode:
21 (exist,new,active) = FULL STATUS if "link reliable"
22 = 0, 0, 0 if "link unreliable"
23 No LMI:
24 active = open and "link reliable"
25 exist = new = not used
26
27 CCITT LMI: ITU-T Q.933 Annex A
28 ANSI LMI: ANSI T1.617 Annex D
29 CISCO LMI: the original, aka "Gang of Four" LMI
30
31 */
32
33 #include <linux/errno.h>
34 #include <linux/etherdevice.h>
35 #include <linux/hdlc.h>
36 #include <linux/if_arp.h>
37 #include <linux/inetdevice.h>
38 #include <linux/init.h>
39 #include <linux/kernel.h>
40 #include <linux/module.h>
41 #include <linux/pkt_sched.h>
42 #include <linux/poll.h>
43 #include <linux/rtnetlink.h>
44 #include <linux/skbuff.h>
45 #include <linux/slab.h>
46
47 #undef DEBUG_PKT
48 #undef DEBUG_ECN
49 #undef DEBUG_LINK
50 #undef DEBUG_PROTO
51 #undef DEBUG_PVC
52
53 #define FR_UI 0x03
54 #define FR_PAD 0x00
55
56 #define NLPID_IP 0xCC
57 #define NLPID_IPV6 0x8E
58 #define NLPID_SNAP 0x80
59 #define NLPID_PAD 0x00
60 #define NLPID_CCITT_ANSI_LMI 0x08
61 #define NLPID_CISCO_LMI 0x09
62
63 #define LMI_CCITT_ANSI_DLCI 0 /* LMI DLCI */
64 #define LMI_CISCO_DLCI 1023
65
66 #define LMI_CALLREF 0x00 /* Call Reference */
67 #define LMI_ANSI_LOCKSHIFT 0x95 /* ANSI locking shift */
68 #define LMI_ANSI_CISCO_REPTYPE 0x01 /* report type */
69 #define LMI_CCITT_REPTYPE 0x51
70 #define LMI_ANSI_CISCO_ALIVE 0x03 /* keep alive */
71 #define LMI_CCITT_ALIVE 0x53
72 #define LMI_ANSI_CISCO_PVCSTAT 0x07 /* PVC status */
73 #define LMI_CCITT_PVCSTAT 0x57
74
75 #define LMI_FULLREP 0x00 /* full report */
76 #define LMI_INTEGRITY 0x01 /* link integrity report */
77 #define LMI_SINGLE 0x02 /* single PVC report */
78
79 #define LMI_STATUS_ENQUIRY 0x75
80 #define LMI_STATUS 0x7D /* reply */
81
82 #define LMI_REPT_LEN 1 /* report type element length */
83 #define LMI_INTEG_LEN 2 /* link integrity element length */
84
85 #define LMI_CCITT_CISCO_LENGTH 13 /* LMI frame lengths */
86 #define LMI_ANSI_LENGTH 14
87
88 struct fr_hdr {
89 #if defined(__LITTLE_ENDIAN_BITFIELD)
90 unsigned ea1: 1;
91 unsigned cr: 1;
92 unsigned dlcih: 6;
93
94 unsigned ea2: 1;
95 unsigned de: 1;
96 unsigned becn: 1;
97 unsigned fecn: 1;
98 unsigned dlcil: 4;
99 #else
100 unsigned dlcih: 6;
101 unsigned cr: 1;
102 unsigned ea1: 1;
103
104 unsigned dlcil: 4;
105 unsigned fecn: 1;
106 unsigned becn: 1;
107 unsigned de: 1;
108 unsigned ea2: 1;
109 #endif
110 } __packed;
111
112 struct pvc_device {
113 struct net_device *frad;
114 struct net_device *main;
115 struct net_device *ether; /* bridged Ethernet interface */
116 struct pvc_device *next; /* Sorted in ascending DLCI order */
117 int dlci;
118 int open_count;
119
120 struct {
121 unsigned int new: 1;
122 unsigned int active: 1;
123 unsigned int exist: 1;
124 unsigned int deleted: 1;
125 unsigned int fecn: 1;
126 unsigned int becn: 1;
127 unsigned int bandwidth; /* Cisco LMI reporting only */
128 } state;
129 };
130
131 struct frad_state {
132 fr_proto settings;
133 struct pvc_device *first_pvc;
134 int dce_pvc_count;
135
136 struct timer_list timer;
137 struct net_device *dev;
138 unsigned long last_poll;
139 int reliable;
140 int dce_changed;
141 int request;
142 int fullrep_sent;
143 u32 last_errors; /* last errors bit list */
144 u8 n391cnt;
145 u8 txseq; /* TX sequence number */
146 u8 rxseq; /* RX sequence number */
147 };
148
149 static int fr_ioctl(struct net_device *dev, struct if_settings *ifs);
150
q922_to_dlci(u8 * hdr)151 static inline u16 q922_to_dlci(u8 *hdr)
152 {
153 return ((hdr[0] & 0xFC) << 2) | ((hdr[1] & 0xF0) >> 4);
154 }
155
dlci_to_q922(u8 * hdr,u16 dlci)156 static inline void dlci_to_q922(u8 *hdr, u16 dlci)
157 {
158 hdr[0] = (dlci >> 2) & 0xFC;
159 hdr[1] = ((dlci << 4) & 0xF0) | 0x01;
160 }
161
state(hdlc_device * hdlc)162 static inline struct frad_state *state(hdlc_device *hdlc)
163 {
164 return (struct frad_state *)(hdlc->state);
165 }
166
find_pvc(hdlc_device * hdlc,u16 dlci)167 static inline struct pvc_device *find_pvc(hdlc_device *hdlc, u16 dlci)
168 {
169 struct pvc_device *pvc = state(hdlc)->first_pvc;
170
171 while (pvc) {
172 if (pvc->dlci == dlci)
173 return pvc;
174 if (pvc->dlci > dlci)
175 return NULL; /* the list is sorted */
176 pvc = pvc->next;
177 }
178
179 return NULL;
180 }
181
add_pvc(struct net_device * dev,u16 dlci)182 static struct pvc_device *add_pvc(struct net_device *dev, u16 dlci)
183 {
184 hdlc_device *hdlc = dev_to_hdlc(dev);
185 struct pvc_device *pvc, **pvc_p = &state(hdlc)->first_pvc;
186
187 while (*pvc_p) {
188 if ((*pvc_p)->dlci == dlci)
189 return *pvc_p;
190 if ((*pvc_p)->dlci > dlci)
191 break; /* the list is sorted */
192 pvc_p = &(*pvc_p)->next;
193 }
194
195 pvc = kzalloc(sizeof(*pvc), GFP_ATOMIC);
196 #ifdef DEBUG_PVC
197 printk(KERN_DEBUG "add_pvc: allocated pvc %p, frad %p\n", pvc, dev);
198 #endif
199 if (!pvc)
200 return NULL;
201
202 pvc->dlci = dlci;
203 pvc->frad = dev;
204 pvc->next = *pvc_p; /* Put it in the chain */
205 *pvc_p = pvc;
206 return pvc;
207 }
208
pvc_is_used(struct pvc_device * pvc)209 static inline int pvc_is_used(struct pvc_device *pvc)
210 {
211 return pvc->main || pvc->ether;
212 }
213
pvc_carrier(int on,struct pvc_device * pvc)214 static inline void pvc_carrier(int on, struct pvc_device *pvc)
215 {
216 if (on) {
217 if (pvc->main)
218 if (!netif_carrier_ok(pvc->main))
219 netif_carrier_on(pvc->main);
220 if (pvc->ether)
221 if (!netif_carrier_ok(pvc->ether))
222 netif_carrier_on(pvc->ether);
223 } else {
224 if (pvc->main)
225 if (netif_carrier_ok(pvc->main))
226 netif_carrier_off(pvc->main);
227 if (pvc->ether)
228 if (netif_carrier_ok(pvc->ether))
229 netif_carrier_off(pvc->ether);
230 }
231 }
232
delete_unused_pvcs(hdlc_device * hdlc)233 static inline void delete_unused_pvcs(hdlc_device *hdlc)
234 {
235 struct pvc_device **pvc_p = &state(hdlc)->first_pvc;
236
237 while (*pvc_p) {
238 if (!pvc_is_used(*pvc_p)) {
239 struct pvc_device *pvc = *pvc_p;
240 #ifdef DEBUG_PVC
241 printk(KERN_DEBUG "freeing unused pvc: %p\n", pvc);
242 #endif
243 *pvc_p = pvc->next;
244 kfree(pvc);
245 continue;
246 }
247 pvc_p = &(*pvc_p)->next;
248 }
249 }
250
get_dev_p(struct pvc_device * pvc,int type)251 static inline struct net_device **get_dev_p(struct pvc_device *pvc,
252 int type)
253 {
254 if (type == ARPHRD_ETHER)
255 return &pvc->ether;
256 else
257 return &pvc->main;
258 }
259
fr_hard_header(struct sk_buff * skb,u16 dlci)260 static int fr_hard_header(struct sk_buff *skb, u16 dlci)
261 {
262 if (!skb->dev) { /* Control packets */
263 switch (dlci) {
264 case LMI_CCITT_ANSI_DLCI:
265 skb_push(skb, 4);
266 skb->data[3] = NLPID_CCITT_ANSI_LMI;
267 break;
268
269 case LMI_CISCO_DLCI:
270 skb_push(skb, 4);
271 skb->data[3] = NLPID_CISCO_LMI;
272 break;
273
274 default:
275 return -EINVAL;
276 }
277
278 } else if (skb->dev->type == ARPHRD_DLCI) {
279 switch (skb->protocol) {
280 case htons(ETH_P_IP):
281 skb_push(skb, 4);
282 skb->data[3] = NLPID_IP;
283 break;
284
285 case htons(ETH_P_IPV6):
286 skb_push(skb, 4);
287 skb->data[3] = NLPID_IPV6;
288 break;
289
290 default:
291 skb_push(skb, 10);
292 skb->data[3] = FR_PAD;
293 skb->data[4] = NLPID_SNAP;
294 /* OUI 00-00-00 indicates an Ethertype follows */
295 skb->data[5] = 0x00;
296 skb->data[6] = 0x00;
297 skb->data[7] = 0x00;
298 /* This should be an Ethertype: */
299 *(__be16 *)(skb->data + 8) = skb->protocol;
300 }
301
302 } else if (skb->dev->type == ARPHRD_ETHER) {
303 skb_push(skb, 10);
304 skb->data[3] = FR_PAD;
305 skb->data[4] = NLPID_SNAP;
306 /* OUI 00-80-C2 stands for the 802.1 organization */
307 skb->data[5] = 0x00;
308 skb->data[6] = 0x80;
309 skb->data[7] = 0xC2;
310 /* PID 00-07 stands for Ethernet frames without FCS */
311 skb->data[8] = 0x00;
312 skb->data[9] = 0x07;
313
314 } else {
315 return -EINVAL;
316 }
317
318 dlci_to_q922(skb->data, dlci);
319 skb->data[2] = FR_UI;
320 return 0;
321 }
322
pvc_open(struct net_device * dev)323 static int pvc_open(struct net_device *dev)
324 {
325 struct pvc_device *pvc = dev->ml_priv;
326
327 if ((pvc->frad->flags & IFF_UP) == 0)
328 return -EIO; /* Frad must be UP in order to activate PVC */
329
330 if (pvc->open_count++ == 0) {
331 hdlc_device *hdlc = dev_to_hdlc(pvc->frad);
332
333 if (state(hdlc)->settings.lmi == LMI_NONE)
334 pvc->state.active = netif_carrier_ok(pvc->frad);
335
336 pvc_carrier(pvc->state.active, pvc);
337 state(hdlc)->dce_changed = 1;
338 }
339 return 0;
340 }
341
pvc_close(struct net_device * dev)342 static int pvc_close(struct net_device *dev)
343 {
344 struct pvc_device *pvc = dev->ml_priv;
345
346 if (--pvc->open_count == 0) {
347 hdlc_device *hdlc = dev_to_hdlc(pvc->frad);
348
349 if (state(hdlc)->settings.lmi == LMI_NONE)
350 pvc->state.active = 0;
351
352 if (state(hdlc)->settings.dce) {
353 state(hdlc)->dce_changed = 1;
354 pvc->state.active = 0;
355 }
356 }
357 return 0;
358 }
359
pvc_ioctl(struct net_device * dev,struct if_settings * ifs)360 static int pvc_ioctl(struct net_device *dev, struct if_settings *ifs)
361 {
362 struct pvc_device *pvc = dev->ml_priv;
363 fr_proto_pvc_info info;
364
365 if (ifs->type == IF_GET_PROTO) {
366 if (dev->type == ARPHRD_ETHER)
367 ifs->type = IF_PROTO_FR_ETH_PVC;
368 else
369 ifs->type = IF_PROTO_FR_PVC;
370
371 if (ifs->size < sizeof(info)) {
372 /* data size wanted */
373 ifs->size = sizeof(info);
374 return -ENOBUFS;
375 }
376
377 info.dlci = pvc->dlci;
378 memcpy(info.master, pvc->frad->name, IFNAMSIZ);
379 if (copy_to_user(ifs->ifs_ifsu.fr_pvc_info,
380 &info, sizeof(info)))
381 return -EFAULT;
382 return 0;
383 }
384
385 return -EINVAL;
386 }
387
pvc_xmit(struct sk_buff * skb,struct net_device * dev)388 static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev)
389 {
390 struct pvc_device *pvc = dev->ml_priv;
391
392 if (!pvc->state.active)
393 goto drop;
394
395 if (dev->type == ARPHRD_ETHER) {
396 int pad = ETH_ZLEN - skb->len;
397
398 if (pad > 0) { /* Pad the frame with zeros */
399 if (__skb_pad(skb, pad, false))
400 goto drop;
401 skb_put(skb, pad);
402 }
403 }
404
405 /* We already requested the header space with dev->needed_headroom.
406 * So this is just a protection in case the upper layer didn't take
407 * dev->needed_headroom into consideration.
408 */
409 if (skb_headroom(skb) < 10) {
410 struct sk_buff *skb2 = skb_realloc_headroom(skb, 10);
411
412 if (!skb2)
413 goto drop;
414 dev_kfree_skb(skb);
415 skb = skb2;
416 }
417
418 skb->dev = dev;
419 if (fr_hard_header(skb, pvc->dlci))
420 goto drop;
421
422 dev->stats.tx_bytes += skb->len;
423 dev->stats.tx_packets++;
424 if (pvc->state.fecn) /* TX Congestion counter */
425 dev->stats.tx_compressed++;
426 skb->dev = pvc->frad;
427 skb->protocol = htons(ETH_P_HDLC);
428 skb_reset_network_header(skb);
429 dev_queue_xmit(skb);
430 return NETDEV_TX_OK;
431
432 drop:
433 dev->stats.tx_dropped++;
434 kfree_skb(skb);
435 return NETDEV_TX_OK;
436 }
437
fr_log_dlci_active(struct pvc_device * pvc)438 static inline void fr_log_dlci_active(struct pvc_device *pvc)
439 {
440 netdev_info(pvc->frad, "DLCI %d [%s%s%s]%s %s\n",
441 pvc->dlci,
442 pvc->main ? pvc->main->name : "",
443 pvc->main && pvc->ether ? " " : "",
444 pvc->ether ? pvc->ether->name : "",
445 pvc->state.new ? " new" : "",
446 !pvc->state.exist ? "deleted" :
447 pvc->state.active ? "active" : "inactive");
448 }
449
fr_lmi_nextseq(u8 x)450 static inline u8 fr_lmi_nextseq(u8 x)
451 {
452 x++;
453 return x ? x : 1;
454 }
455
fr_lmi_send(struct net_device * dev,int fullrep)456 static void fr_lmi_send(struct net_device *dev, int fullrep)
457 {
458 hdlc_device *hdlc = dev_to_hdlc(dev);
459 struct sk_buff *skb;
460 struct pvc_device *pvc = state(hdlc)->first_pvc;
461 int lmi = state(hdlc)->settings.lmi;
462 int dce = state(hdlc)->settings.dce;
463 int len = lmi == LMI_ANSI ? LMI_ANSI_LENGTH : LMI_CCITT_CISCO_LENGTH;
464 int stat_len = (lmi == LMI_CISCO) ? 6 : 3;
465 u8 *data;
466 int i = 0;
467
468 if (dce && fullrep) {
469 len += state(hdlc)->dce_pvc_count * (2 + stat_len);
470 if (len > HDLC_MAX_MRU) {
471 netdev_warn(dev, "Too many PVCs while sending LMI full report\n");
472 return;
473 }
474 }
475
476 skb = dev_alloc_skb(len);
477 if (!skb)
478 return;
479
480 memset(skb->data, 0, len);
481 skb_reserve(skb, 4);
482 if (lmi == LMI_CISCO)
483 fr_hard_header(skb, LMI_CISCO_DLCI);
484 else
485 fr_hard_header(skb, LMI_CCITT_ANSI_DLCI);
486
487 data = skb_tail_pointer(skb);
488 data[i++] = LMI_CALLREF;
489 data[i++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
490 if (lmi == LMI_ANSI)
491 data[i++] = LMI_ANSI_LOCKSHIFT;
492 data[i++] = lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
493 LMI_ANSI_CISCO_REPTYPE;
494 data[i++] = LMI_REPT_LEN;
495 data[i++] = fullrep ? LMI_FULLREP : LMI_INTEGRITY;
496 data[i++] = lmi == LMI_CCITT ? LMI_CCITT_ALIVE : LMI_ANSI_CISCO_ALIVE;
497 data[i++] = LMI_INTEG_LEN;
498 data[i++] = state(hdlc)->txseq =
499 fr_lmi_nextseq(state(hdlc)->txseq);
500 data[i++] = state(hdlc)->rxseq;
501
502 if (dce && fullrep) {
503 while (pvc) {
504 data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
505 LMI_ANSI_CISCO_PVCSTAT;
506 data[i++] = stat_len;
507
508 /* LMI start/restart */
509 if (state(hdlc)->reliable && !pvc->state.exist) {
510 pvc->state.exist = pvc->state.new = 1;
511 fr_log_dlci_active(pvc);
512 }
513
514 /* ifconfig PVC up */
515 if (pvc->open_count && !pvc->state.active &&
516 pvc->state.exist && !pvc->state.new) {
517 pvc_carrier(1, pvc);
518 pvc->state.active = 1;
519 fr_log_dlci_active(pvc);
520 }
521
522 if (lmi == LMI_CISCO) {
523 data[i] = pvc->dlci >> 8;
524 data[i + 1] = pvc->dlci & 0xFF;
525 } else {
526 data[i] = (pvc->dlci >> 4) & 0x3F;
527 data[i + 1] = ((pvc->dlci << 3) & 0x78) | 0x80;
528 data[i + 2] = 0x80;
529 }
530
531 if (pvc->state.new)
532 data[i + 2] |= 0x08;
533 else if (pvc->state.active)
534 data[i + 2] |= 0x02;
535
536 i += stat_len;
537 pvc = pvc->next;
538 }
539 }
540
541 skb_put(skb, i);
542 skb->priority = TC_PRIO_CONTROL;
543 skb->dev = dev;
544 skb->protocol = htons(ETH_P_HDLC);
545 skb_reset_network_header(skb);
546
547 dev_queue_xmit(skb);
548 }
549
fr_set_link_state(int reliable,struct net_device * dev)550 static void fr_set_link_state(int reliable, struct net_device *dev)
551 {
552 hdlc_device *hdlc = dev_to_hdlc(dev);
553 struct pvc_device *pvc = state(hdlc)->first_pvc;
554
555 state(hdlc)->reliable = reliable;
556 if (reliable) {
557 netif_dormant_off(dev);
558 state(hdlc)->n391cnt = 0; /* Request full status */
559 state(hdlc)->dce_changed = 1;
560
561 if (state(hdlc)->settings.lmi == LMI_NONE) {
562 while (pvc) { /* Activate all PVCs */
563 pvc_carrier(1, pvc);
564 pvc->state.exist = pvc->state.active = 1;
565 pvc->state.new = 0;
566 pvc = pvc->next;
567 }
568 }
569 } else {
570 netif_dormant_on(dev);
571 while (pvc) { /* Deactivate all PVCs */
572 pvc_carrier(0, pvc);
573 pvc->state.exist = pvc->state.active = 0;
574 pvc->state.new = 0;
575 if (!state(hdlc)->settings.dce)
576 pvc->state.bandwidth = 0;
577 pvc = pvc->next;
578 }
579 }
580 }
581
fr_timer(struct timer_list * t)582 static void fr_timer(struct timer_list *t)
583 {
584 struct frad_state *st = timer_container_of(st, t, timer);
585 struct net_device *dev = st->dev;
586 hdlc_device *hdlc = dev_to_hdlc(dev);
587 int i, cnt = 0, reliable;
588 u32 list;
589
590 if (state(hdlc)->settings.dce) {
591 reliable = state(hdlc)->request &&
592 time_before(jiffies, state(hdlc)->last_poll +
593 state(hdlc)->settings.t392 * HZ);
594 state(hdlc)->request = 0;
595 } else {
596 state(hdlc)->last_errors <<= 1; /* Shift the list */
597 if (state(hdlc)->request) {
598 if (state(hdlc)->reliable)
599 netdev_info(dev, "No LMI status reply received\n");
600 state(hdlc)->last_errors |= 1;
601 }
602
603 list = state(hdlc)->last_errors;
604 for (i = 0; i < state(hdlc)->settings.n393; i++, list >>= 1)
605 cnt += (list & 1); /* errors count */
606
607 reliable = (cnt < state(hdlc)->settings.n392);
608 }
609
610 if (state(hdlc)->reliable != reliable) {
611 netdev_info(dev, "Link %sreliable\n", reliable ? "" : "un");
612 fr_set_link_state(reliable, dev);
613 }
614
615 if (state(hdlc)->settings.dce) {
616 state(hdlc)->timer.expires = jiffies +
617 state(hdlc)->settings.t392 * HZ;
618 } else {
619 if (state(hdlc)->n391cnt)
620 state(hdlc)->n391cnt--;
621
622 fr_lmi_send(dev, state(hdlc)->n391cnt == 0);
623
624 state(hdlc)->last_poll = jiffies;
625 state(hdlc)->request = 1;
626 state(hdlc)->timer.expires = jiffies +
627 state(hdlc)->settings.t391 * HZ;
628 }
629
630 add_timer(&state(hdlc)->timer);
631 }
632
fr_lmi_recv(struct net_device * dev,struct sk_buff * skb)633 static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
634 {
635 hdlc_device *hdlc = dev_to_hdlc(dev);
636 struct pvc_device *pvc;
637 u8 rxseq, txseq;
638 int lmi = state(hdlc)->settings.lmi;
639 int dce = state(hdlc)->settings.dce;
640 int stat_len = (lmi == LMI_CISCO) ? 6 : 3, reptype, error, no_ram, i;
641
642 if (skb->len < (lmi == LMI_ANSI ? LMI_ANSI_LENGTH :
643 LMI_CCITT_CISCO_LENGTH)) {
644 netdev_info(dev, "Short LMI frame\n");
645 return 1;
646 }
647
648 if (skb->data[3] != (lmi == LMI_CISCO ? NLPID_CISCO_LMI :
649 NLPID_CCITT_ANSI_LMI)) {
650 netdev_info(dev, "Received non-LMI frame with LMI DLCI\n");
651 return 1;
652 }
653
654 if (skb->data[4] != LMI_CALLREF) {
655 netdev_info(dev, "Invalid LMI Call reference (0x%02X)\n",
656 skb->data[4]);
657 return 1;
658 }
659
660 if (skb->data[5] != (dce ? LMI_STATUS_ENQUIRY : LMI_STATUS)) {
661 netdev_info(dev, "Invalid LMI Message type (0x%02X)\n",
662 skb->data[5]);
663 return 1;
664 }
665
666 if (lmi == LMI_ANSI) {
667 if (skb->data[6] != LMI_ANSI_LOCKSHIFT) {
668 netdev_info(dev, "Not ANSI locking shift in LMI message (0x%02X)\n",
669 skb->data[6]);
670 return 1;
671 }
672 i = 7;
673 } else {
674 i = 6;
675 }
676
677 if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
678 LMI_ANSI_CISCO_REPTYPE)) {
679 netdev_info(dev, "Not an LMI Report type IE (0x%02X)\n",
680 skb->data[i]);
681 return 1;
682 }
683
684 if (skb->data[++i] != LMI_REPT_LEN) {
685 netdev_info(dev, "Invalid LMI Report type IE length (%u)\n",
686 skb->data[i]);
687 return 1;
688 }
689
690 reptype = skb->data[++i];
691 if (reptype != LMI_INTEGRITY && reptype != LMI_FULLREP) {
692 netdev_info(dev, "Unsupported LMI Report type (0x%02X)\n",
693 reptype);
694 return 1;
695 }
696
697 if (skb->data[++i] != (lmi == LMI_CCITT ? LMI_CCITT_ALIVE :
698 LMI_ANSI_CISCO_ALIVE)) {
699 netdev_info(dev, "Not an LMI Link integrity verification IE (0x%02X)\n",
700 skb->data[i]);
701 return 1;
702 }
703
704 if (skb->data[++i] != LMI_INTEG_LEN) {
705 netdev_info(dev, "Invalid LMI Link integrity verification IE length (%u)\n",
706 skb->data[i]);
707 return 1;
708 }
709 i++;
710
711 state(hdlc)->rxseq = skb->data[i++]; /* TX sequence from peer */
712 rxseq = skb->data[i++]; /* Should confirm our sequence */
713
714 txseq = state(hdlc)->txseq;
715
716 if (dce)
717 state(hdlc)->last_poll = jiffies;
718
719 error = 0;
720 if (!state(hdlc)->reliable)
721 error = 1;
722
723 if (rxseq == 0 || rxseq != txseq) { /* Ask for full report next time */
724 state(hdlc)->n391cnt = 0;
725 error = 1;
726 }
727
728 if (dce) {
729 if (state(hdlc)->fullrep_sent && !error) {
730 /* Stop sending full report - the last one has been confirmed by DTE */
731 state(hdlc)->fullrep_sent = 0;
732 pvc = state(hdlc)->first_pvc;
733 while (pvc) {
734 if (pvc->state.new) {
735 pvc->state.new = 0;
736
737 /* Tell DTE that new PVC is now active */
738 state(hdlc)->dce_changed = 1;
739 }
740 pvc = pvc->next;
741 }
742 }
743
744 if (state(hdlc)->dce_changed) {
745 reptype = LMI_FULLREP;
746 state(hdlc)->fullrep_sent = 1;
747 state(hdlc)->dce_changed = 0;
748 }
749
750 state(hdlc)->request = 1; /* got request */
751 fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
752 return 0;
753 }
754
755 /* DTE */
756
757 state(hdlc)->request = 0; /* got response, no request pending */
758
759 if (error)
760 return 0;
761
762 if (reptype != LMI_FULLREP)
763 return 0;
764
765 pvc = state(hdlc)->first_pvc;
766
767 while (pvc) {
768 pvc->state.deleted = 1;
769 pvc = pvc->next;
770 }
771
772 no_ram = 0;
773 while (skb->len >= i + 2 + stat_len) {
774 u16 dlci;
775 u32 bw;
776 unsigned int active, new;
777
778 if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
779 LMI_ANSI_CISCO_PVCSTAT)) {
780 netdev_info(dev, "Not an LMI PVC status IE (0x%02X)\n",
781 skb->data[i]);
782 return 1;
783 }
784
785 if (skb->data[++i] != stat_len) {
786 netdev_info(dev, "Invalid LMI PVC status IE length (%u)\n",
787 skb->data[i]);
788 return 1;
789 }
790 i++;
791
792 new = !!(skb->data[i + 2] & 0x08);
793 active = !!(skb->data[i + 2] & 0x02);
794 if (lmi == LMI_CISCO) {
795 dlci = (skb->data[i] << 8) | skb->data[i + 1];
796 bw = (skb->data[i + 3] << 16) |
797 (skb->data[i + 4] << 8) |
798 (skb->data[i + 5]);
799 } else {
800 dlci = ((skb->data[i] & 0x3F) << 4) |
801 ((skb->data[i + 1] & 0x78) >> 3);
802 bw = 0;
803 }
804
805 pvc = add_pvc(dev, dlci);
806
807 if (!pvc && !no_ram) {
808 netdev_warn(dev, "Memory squeeze on fr_lmi_recv()\n");
809 no_ram = 1;
810 }
811
812 if (pvc) {
813 pvc->state.exist = 1;
814 pvc->state.deleted = 0;
815 if (active != pvc->state.active ||
816 new != pvc->state.new ||
817 bw != pvc->state.bandwidth ||
818 !pvc->state.exist) {
819 pvc->state.new = new;
820 pvc->state.active = active;
821 pvc->state.bandwidth = bw;
822 pvc_carrier(active, pvc);
823 fr_log_dlci_active(pvc);
824 }
825 }
826
827 i += stat_len;
828 }
829
830 pvc = state(hdlc)->first_pvc;
831
832 while (pvc) {
833 if (pvc->state.deleted && pvc->state.exist) {
834 pvc_carrier(0, pvc);
835 pvc->state.active = pvc->state.new = 0;
836 pvc->state.exist = 0;
837 pvc->state.bandwidth = 0;
838 fr_log_dlci_active(pvc);
839 }
840 pvc = pvc->next;
841 }
842
843 /* Next full report after N391 polls */
844 state(hdlc)->n391cnt = state(hdlc)->settings.n391;
845
846 return 0;
847 }
848
fr_snap_parse(struct sk_buff * skb,struct pvc_device * pvc)849 static int fr_snap_parse(struct sk_buff *skb, struct pvc_device *pvc)
850 {
851 /* OUI 00-00-00 indicates an Ethertype follows */
852 if (skb->data[0] == 0x00 &&
853 skb->data[1] == 0x00 &&
854 skb->data[2] == 0x00) {
855 if (!pvc->main)
856 return -1;
857 skb->dev = pvc->main;
858 skb->protocol = *(__be16 *)(skb->data + 3); /* Ethertype */
859 skb_pull(skb, 5);
860 skb_reset_mac_header(skb);
861 return 0;
862
863 /* OUI 00-80-C2 stands for the 802.1 organization */
864 } else if (skb->data[0] == 0x00 &&
865 skb->data[1] == 0x80 &&
866 skb->data[2] == 0xC2) {
867 /* PID 00-07 stands for Ethernet frames without FCS */
868 if (skb->data[3] == 0x00 &&
869 skb->data[4] == 0x07) {
870 if (!pvc->ether)
871 return -1;
872 skb_pull(skb, 5);
873 if (skb->len < ETH_HLEN)
874 return -1;
875 skb->protocol = eth_type_trans(skb, pvc->ether);
876 return 0;
877
878 /* PID unsupported */
879 } else {
880 return -1;
881 }
882
883 /* OUI unsupported */
884 } else {
885 return -1;
886 }
887 }
888
fr_rx(struct sk_buff * skb)889 static int fr_rx(struct sk_buff *skb)
890 {
891 struct net_device *frad = skb->dev;
892 hdlc_device *hdlc = dev_to_hdlc(frad);
893 struct fr_hdr *fh = (struct fr_hdr *)skb->data;
894 u8 *data = skb->data;
895 u16 dlci;
896 struct pvc_device *pvc;
897 struct net_device *dev;
898
899 if (skb->len < 4 || fh->ea1 || !fh->ea2 || data[2] != FR_UI)
900 goto rx_error;
901
902 dlci = q922_to_dlci(skb->data);
903
904 if ((dlci == LMI_CCITT_ANSI_DLCI &&
905 (state(hdlc)->settings.lmi == LMI_ANSI ||
906 state(hdlc)->settings.lmi == LMI_CCITT)) ||
907 (dlci == LMI_CISCO_DLCI &&
908 state(hdlc)->settings.lmi == LMI_CISCO)) {
909 if (fr_lmi_recv(frad, skb))
910 goto rx_error;
911 dev_kfree_skb_any(skb);
912 return NET_RX_SUCCESS;
913 }
914
915 pvc = find_pvc(hdlc, dlci);
916 if (!pvc) {
917 #ifdef DEBUG_PKT
918 netdev_info(frad, "No PVC for received frame's DLCI %d\n",
919 dlci);
920 #endif
921 goto rx_drop;
922 }
923
924 if (pvc->state.fecn != fh->fecn) {
925 #ifdef DEBUG_ECN
926 printk(KERN_DEBUG "%s: DLCI %d FECN O%s\n", frad->name,
927 dlci, fh->fecn ? "N" : "FF");
928 #endif
929 pvc->state.fecn ^= 1;
930 }
931
932 if (pvc->state.becn != fh->becn) {
933 #ifdef DEBUG_ECN
934 printk(KERN_DEBUG "%s: DLCI %d BECN O%s\n", frad->name,
935 dlci, fh->becn ? "N" : "FF");
936 #endif
937 pvc->state.becn ^= 1;
938 }
939
940 skb = skb_share_check(skb, GFP_ATOMIC);
941 if (!skb) {
942 frad->stats.rx_dropped++;
943 return NET_RX_DROP;
944 }
945
946 if (data[3] == NLPID_IP) {
947 if (!pvc->main)
948 goto rx_drop;
949 skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
950 skb->dev = pvc->main;
951 skb->protocol = htons(ETH_P_IP);
952 skb_reset_mac_header(skb);
953
954 } else if (data[3] == NLPID_IPV6) {
955 if (!pvc->main)
956 goto rx_drop;
957 skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
958 skb->dev = pvc->main;
959 skb->protocol = htons(ETH_P_IPV6);
960 skb_reset_mac_header(skb);
961
962 } else if (data[3] == FR_PAD) {
963 if (skb->len < 5)
964 goto rx_error;
965 if (data[4] == NLPID_SNAP) { /* A SNAP header follows */
966 skb_pull(skb, 5);
967 if (skb->len < 5) /* Incomplete SNAP header */
968 goto rx_error;
969 if (fr_snap_parse(skb, pvc))
970 goto rx_drop;
971 } else {
972 goto rx_drop;
973 }
974
975 } else {
976 netdev_info(frad, "Unsupported protocol, NLPID=%x length=%i\n",
977 data[3], skb->len);
978 goto rx_drop;
979 }
980
981 dev = skb->dev;
982 dev->stats.rx_packets++; /* PVC traffic */
983 dev->stats.rx_bytes += skb->len;
984 if (pvc->state.becn)
985 dev->stats.rx_compressed++;
986 netif_rx(skb);
987 return NET_RX_SUCCESS;
988
989 rx_error:
990 frad->stats.rx_errors++; /* Mark error */
991 rx_drop:
992 dev_kfree_skb_any(skb);
993 return NET_RX_DROP;
994 }
995
fr_start(struct net_device * dev)996 static void fr_start(struct net_device *dev)
997 {
998 hdlc_device *hdlc = dev_to_hdlc(dev);
999 #ifdef DEBUG_LINK
1000 printk(KERN_DEBUG "fr_start\n");
1001 #endif
1002 if (state(hdlc)->settings.lmi != LMI_NONE) {
1003 state(hdlc)->reliable = 0;
1004 state(hdlc)->dce_changed = 1;
1005 state(hdlc)->request = 0;
1006 state(hdlc)->fullrep_sent = 0;
1007 state(hdlc)->last_errors = 0xFFFFFFFF;
1008 state(hdlc)->n391cnt = 0;
1009 state(hdlc)->txseq = state(hdlc)->rxseq = 0;
1010
1011 state(hdlc)->dev = dev;
1012 timer_setup(&state(hdlc)->timer, fr_timer, 0);
1013 /* First poll after 1 s */
1014 state(hdlc)->timer.expires = jiffies + HZ;
1015 add_timer(&state(hdlc)->timer);
1016 } else {
1017 fr_set_link_state(1, dev);
1018 }
1019 }
1020
fr_stop(struct net_device * dev)1021 static void fr_stop(struct net_device *dev)
1022 {
1023 hdlc_device *hdlc = dev_to_hdlc(dev);
1024 #ifdef DEBUG_LINK
1025 printk(KERN_DEBUG "fr_stop\n");
1026 #endif
1027 if (state(hdlc)->settings.lmi != LMI_NONE)
1028 timer_delete_sync(&state(hdlc)->timer);
1029 fr_set_link_state(0, dev);
1030 }
1031
fr_close(struct net_device * dev)1032 static void fr_close(struct net_device *dev)
1033 {
1034 hdlc_device *hdlc = dev_to_hdlc(dev);
1035 struct pvc_device *pvc = state(hdlc)->first_pvc;
1036
1037 while (pvc) { /* Shutdown all PVCs for this FRAD */
1038 if (pvc->main)
1039 dev_close(pvc->main);
1040 if (pvc->ether)
1041 dev_close(pvc->ether);
1042 pvc = pvc->next;
1043 }
1044 }
1045
pvc_setup(struct net_device * dev)1046 static void pvc_setup(struct net_device *dev)
1047 {
1048 dev->type = ARPHRD_DLCI;
1049 dev->flags = IFF_POINTOPOINT;
1050 dev->hard_header_len = 0;
1051 dev->addr_len = 2;
1052 netif_keep_dst(dev);
1053 }
1054
1055 static const struct net_device_ops pvc_ops = {
1056 .ndo_open = pvc_open,
1057 .ndo_stop = pvc_close,
1058 .ndo_start_xmit = pvc_xmit,
1059 .ndo_siocwandev = pvc_ioctl,
1060 };
1061
fr_add_pvc(struct net_device * frad,unsigned int dlci,int type)1062 static int fr_add_pvc(struct net_device *frad, unsigned int dlci, int type)
1063 {
1064 hdlc_device *hdlc = dev_to_hdlc(frad);
1065 struct pvc_device *pvc;
1066 struct net_device *dev;
1067 int used;
1068
1069 pvc = add_pvc(frad, dlci);
1070 if (!pvc) {
1071 netdev_warn(frad, "Memory squeeze on fr_add_pvc()\n");
1072 return -ENOBUFS;
1073 }
1074
1075 if (*get_dev_p(pvc, type))
1076 return -EEXIST;
1077
1078 used = pvc_is_used(pvc);
1079
1080 if (type == ARPHRD_ETHER)
1081 dev = alloc_netdev(0, "pvceth%d", NET_NAME_UNKNOWN,
1082 ether_setup);
1083 else
1084 dev = alloc_netdev(0, "pvc%d", NET_NAME_UNKNOWN, pvc_setup);
1085
1086 if (!dev) {
1087 netdev_warn(frad, "Memory squeeze on fr_pvc()\n");
1088 delete_unused_pvcs(hdlc);
1089 return -ENOBUFS;
1090 }
1091
1092 if (type == ARPHRD_ETHER) {
1093 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1094 eth_hw_addr_random(dev);
1095 } else {
1096 __be16 addr = htons(dlci);
1097
1098 dev_addr_set(dev, (u8 *)&addr);
1099 dlci_to_q922(dev->broadcast, dlci);
1100 }
1101 dev->netdev_ops = &pvc_ops;
1102 dev->mtu = HDLC_MAX_MTU;
1103 dev->min_mtu = 68;
1104 dev->max_mtu = HDLC_MAX_MTU;
1105 dev->needed_headroom = 10;
1106 dev->priv_flags |= IFF_NO_QUEUE;
1107 dev->ml_priv = pvc;
1108
1109 if (register_netdevice(dev) != 0) {
1110 free_netdev(dev);
1111 delete_unused_pvcs(hdlc);
1112 return -EIO;
1113 }
1114
1115 dev->needs_free_netdev = true;
1116 *get_dev_p(pvc, type) = dev;
1117 if (!used) {
1118 state(hdlc)->dce_changed = 1;
1119 state(hdlc)->dce_pvc_count++;
1120 }
1121 return 0;
1122 }
1123
fr_del_pvc(hdlc_device * hdlc,unsigned int dlci,int type)1124 static int fr_del_pvc(hdlc_device *hdlc, unsigned int dlci, int type)
1125 {
1126 struct pvc_device *pvc;
1127 struct net_device *dev;
1128
1129 pvc = find_pvc(hdlc, dlci);
1130 if (!pvc)
1131 return -ENOENT;
1132
1133 dev = *get_dev_p(pvc, type);
1134 if (!dev)
1135 return -ENOENT;
1136
1137 if (dev->flags & IFF_UP)
1138 return -EBUSY; /* PVC in use */
1139
1140 unregister_netdevice(dev); /* the destructor will free_netdev(dev) */
1141 *get_dev_p(pvc, type) = NULL;
1142
1143 if (!pvc_is_used(pvc)) {
1144 state(hdlc)->dce_pvc_count--;
1145 state(hdlc)->dce_changed = 1;
1146 }
1147 delete_unused_pvcs(hdlc);
1148 return 0;
1149 }
1150
fr_destroy(struct net_device * frad)1151 static void fr_destroy(struct net_device *frad)
1152 {
1153 hdlc_device *hdlc = dev_to_hdlc(frad);
1154 struct pvc_device *pvc = state(hdlc)->first_pvc;
1155
1156 state(hdlc)->first_pvc = NULL; /* All PVCs destroyed */
1157 state(hdlc)->dce_pvc_count = 0;
1158 state(hdlc)->dce_changed = 1;
1159
1160 while (pvc) {
1161 struct pvc_device *next = pvc->next;
1162 /* destructors will free_netdev() main and ether */
1163 if (pvc->main)
1164 unregister_netdevice(pvc->main);
1165
1166 if (pvc->ether)
1167 unregister_netdevice(pvc->ether);
1168
1169 kfree(pvc);
1170 pvc = next;
1171 }
1172 }
1173
1174 static struct hdlc_proto proto = {
1175 .close = fr_close,
1176 .start = fr_start,
1177 .stop = fr_stop,
1178 .detach = fr_destroy,
1179 .ioctl = fr_ioctl,
1180 .netif_rx = fr_rx,
1181 .module = THIS_MODULE,
1182 };
1183
fr_ioctl(struct net_device * dev,struct if_settings * ifs)1184 static int fr_ioctl(struct net_device *dev, struct if_settings *ifs)
1185 {
1186 fr_proto __user *fr_s = ifs->ifs_ifsu.fr;
1187 const size_t size = sizeof(fr_proto);
1188 fr_proto new_settings;
1189 hdlc_device *hdlc = dev_to_hdlc(dev);
1190 fr_proto_pvc pvc;
1191 int result;
1192
1193 switch (ifs->type) {
1194 case IF_GET_PROTO:
1195 if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1196 return -EINVAL;
1197 ifs->type = IF_PROTO_FR;
1198 if (ifs->size < size) {
1199 ifs->size = size; /* data size wanted */
1200 return -ENOBUFS;
1201 }
1202 if (copy_to_user(fr_s, &state(hdlc)->settings, size))
1203 return -EFAULT;
1204 return 0;
1205
1206 case IF_PROTO_FR:
1207 if (!capable(CAP_NET_ADMIN))
1208 return -EPERM;
1209
1210 if (dev->flags & IFF_UP)
1211 return -EBUSY;
1212
1213 if (copy_from_user(&new_settings, fr_s, size))
1214 return -EFAULT;
1215
1216 if (new_settings.lmi == LMI_DEFAULT)
1217 new_settings.lmi = LMI_ANSI;
1218
1219 if ((new_settings.lmi != LMI_NONE &&
1220 new_settings.lmi != LMI_ANSI &&
1221 new_settings.lmi != LMI_CCITT &&
1222 new_settings.lmi != LMI_CISCO) ||
1223 new_settings.t391 < 1 ||
1224 new_settings.t392 < 2 ||
1225 new_settings.n391 < 1 ||
1226 new_settings.n392 < 1 ||
1227 new_settings.n393 < new_settings.n392 ||
1228 new_settings.n393 > 32 ||
1229 (new_settings.dce != 0 &&
1230 new_settings.dce != 1))
1231 return -EINVAL;
1232
1233 result = hdlc->attach(dev, ENCODING_NRZ,
1234 PARITY_CRC16_PR1_CCITT);
1235 if (result)
1236 return result;
1237
1238 if (dev_to_hdlc(dev)->proto != &proto) { /* Different proto */
1239 result = attach_hdlc_protocol(dev, &proto,
1240 sizeof(struct frad_state));
1241 if (result)
1242 return result;
1243 state(hdlc)->first_pvc = NULL;
1244 state(hdlc)->dce_pvc_count = 0;
1245 }
1246 memcpy(&state(hdlc)->settings, &new_settings, size);
1247 dev->type = ARPHRD_FRAD;
1248 call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
1249 return 0;
1250
1251 case IF_PROTO_FR_ADD_PVC:
1252 case IF_PROTO_FR_DEL_PVC:
1253 case IF_PROTO_FR_ADD_ETH_PVC:
1254 case IF_PROTO_FR_DEL_ETH_PVC:
1255 if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1256 return -EINVAL;
1257
1258 if (!capable(CAP_NET_ADMIN))
1259 return -EPERM;
1260
1261 if (copy_from_user(&pvc, ifs->ifs_ifsu.fr_pvc,
1262 sizeof(fr_proto_pvc)))
1263 return -EFAULT;
1264
1265 if (pvc.dlci <= 0 || pvc.dlci >= 1024)
1266 return -EINVAL; /* Only 10 bits, DLCI 0 reserved */
1267
1268 if (ifs->type == IF_PROTO_FR_ADD_ETH_PVC ||
1269 ifs->type == IF_PROTO_FR_DEL_ETH_PVC)
1270 result = ARPHRD_ETHER; /* bridged Ethernet device */
1271 else
1272 result = ARPHRD_DLCI;
1273
1274 if (ifs->type == IF_PROTO_FR_ADD_PVC ||
1275 ifs->type == IF_PROTO_FR_ADD_ETH_PVC)
1276 return fr_add_pvc(dev, pvc.dlci, result);
1277 else
1278 return fr_del_pvc(hdlc, pvc.dlci, result);
1279 }
1280
1281 return -EINVAL;
1282 }
1283
hdlc_fr_init(void)1284 static int __init hdlc_fr_init(void)
1285 {
1286 register_hdlc_protocol(&proto);
1287 return 0;
1288 }
1289
hdlc_fr_exit(void)1290 static void __exit hdlc_fr_exit(void)
1291 {
1292 unregister_hdlc_protocol(&proto);
1293 }
1294
1295 module_init(hdlc_fr_init);
1296 module_exit(hdlc_fr_exit);
1297
1298 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
1299 MODULE_DESCRIPTION("Frame-Relay protocol support for generic HDLC");
1300 MODULE_LICENSE("GPL v2");
1301