xref: /linux/drivers/net/wan/hdlc_fr.c (revision 60b2737de1b1ddfdb90f3ba622634eb49d6f3603)
1 /*
2  * Generic HDLC support routines for Linux
3  * Frame Relay support
4  *
5  * Copyright (C) 1999 - 2005 Krzysztof Halasa <khc@pm.waw.pl>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of version 2 of the GNU General Public License
9  * as published by the Free Software Foundation.
10  *
11 
12             Theory of PVC state
13 
14  DCE mode:
15 
16  (exist,new) -> 0,0 when "PVC create" or if "link unreliable"
17          0,x -> 1,1 if "link reliable" when sending FULL STATUS
18          1,1 -> 1,0 if received FULL STATUS ACK
19 
20  (active)    -> 0 when "ifconfig PVC down" or "link unreliable" or "PVC create"
21              -> 1 when "PVC up" and (exist,new) = 1,0
22 
23  DTE mode:
24  (exist,new,active) = FULL STATUS if "link reliable"
25 		    = 0, 0, 0 if "link unreliable"
26  No LMI:
27  active = open and "link reliable"
28  exist = new = not used
29 
30  CCITT LMI: ITU-T Q.933 Annex A
31  ANSI LMI: ANSI T1.617 Annex D
32  CISCO LMI: the original, aka "Gang of Four" LMI
33 
34 */
35 
36 #include <linux/module.h>
37 #include <linux/kernel.h>
38 #include <linux/slab.h>
39 #include <linux/poll.h>
40 #include <linux/errno.h>
41 #include <linux/if_arp.h>
42 #include <linux/init.h>
43 #include <linux/skbuff.h>
44 #include <linux/pkt_sched.h>
45 #include <linux/random.h>
46 #include <linux/inetdevice.h>
47 #include <linux/lapb.h>
48 #include <linux/rtnetlink.h>
49 #include <linux/etherdevice.h>
50 #include <linux/hdlc.h>
51 
52 #undef DEBUG_PKT
53 #undef DEBUG_ECN
54 #undef DEBUG_LINK
55 
56 #define FR_UI			0x03
57 #define FR_PAD			0x00
58 
59 #define NLPID_IP		0xCC
60 #define NLPID_IPV6		0x8E
61 #define NLPID_SNAP		0x80
62 #define NLPID_PAD		0x00
63 #define NLPID_CCITT_ANSI_LMI	0x08
64 #define NLPID_CISCO_LMI		0x09
65 
66 
67 #define LMI_CCITT_ANSI_DLCI	   0 /* LMI DLCI */
68 #define LMI_CISCO_DLCI		1023
69 
70 #define LMI_CALLREF		0x00 /* Call Reference */
71 #define LMI_ANSI_LOCKSHIFT	0x95 /* ANSI locking shift */
72 #define LMI_ANSI_CISCO_REPTYPE	0x01 /* report type */
73 #define LMI_CCITT_REPTYPE	0x51
74 #define LMI_ANSI_CISCO_ALIVE	0x03 /* keep alive */
75 #define LMI_CCITT_ALIVE		0x53
76 #define LMI_ANSI_CISCO_PVCSTAT	0x07 /* PVC status */
77 #define LMI_CCITT_PVCSTAT	0x57
78 
79 #define LMI_FULLREP		0x00 /* full report  */
80 #define LMI_INTEGRITY		0x01 /* link integrity report */
81 #define LMI_SINGLE		0x02 /* single PVC report */
82 
83 #define LMI_STATUS_ENQUIRY      0x75
84 #define LMI_STATUS              0x7D /* reply */
85 
86 #define LMI_REPT_LEN               1 /* report type element length */
87 #define LMI_INTEG_LEN              2 /* link integrity element length */
88 
89 #define LMI_CCITT_CISCO_LENGTH	  13 /* LMI frame lengths */
90 #define LMI_ANSI_LENGTH		  14
91 
92 
93 typedef struct {
94 #if defined(__LITTLE_ENDIAN_BITFIELD)
95 	unsigned ea1:	1;
96 	unsigned cr:	1;
97 	unsigned dlcih:	6;
98 
99 	unsigned ea2:	1;
100 	unsigned de:	1;
101 	unsigned becn:	1;
102 	unsigned fecn:	1;
103 	unsigned dlcil:	4;
104 #else
105 	unsigned dlcih:	6;
106 	unsigned cr:	1;
107 	unsigned ea1:	1;
108 
109 	unsigned dlcil:	4;
110 	unsigned fecn:	1;
111 	unsigned becn:	1;
112 	unsigned de:	1;
113 	unsigned ea2:	1;
114 #endif
115 }__attribute__ ((packed)) fr_hdr;
116 
117 
118 static inline u16 q922_to_dlci(u8 *hdr)
119 {
120 	return ((hdr[0] & 0xFC) << 2) | ((hdr[1] & 0xF0) >> 4);
121 }
122 
123 
124 
125 static inline void dlci_to_q922(u8 *hdr, u16 dlci)
126 {
127 	hdr[0] = (dlci >> 2) & 0xFC;
128 	hdr[1] = ((dlci << 4) & 0xF0) | 0x01;
129 }
130 
131 
132 
133 static inline pvc_device* find_pvc(hdlc_device *hdlc, u16 dlci)
134 {
135 	pvc_device *pvc = hdlc->state.fr.first_pvc;
136 
137 	while (pvc) {
138 		if (pvc->dlci == dlci)
139 			return pvc;
140 		if (pvc->dlci > dlci)
141 			return NULL; /* the listed is sorted */
142 		pvc = pvc->next;
143 	}
144 
145 	return NULL;
146 }
147 
148 
149 static inline pvc_device* add_pvc(struct net_device *dev, u16 dlci)
150 {
151 	hdlc_device *hdlc = dev_to_hdlc(dev);
152 	pvc_device *pvc, **pvc_p = &hdlc->state.fr.first_pvc;
153 
154 	while (*pvc_p) {
155 		if ((*pvc_p)->dlci == dlci)
156 			return *pvc_p;
157 		if ((*pvc_p)->dlci > dlci)
158 			break;	/* the list is sorted */
159 		pvc_p = &(*pvc_p)->next;
160 	}
161 
162 	pvc = kmalloc(sizeof(pvc_device), GFP_ATOMIC);
163 	if (!pvc)
164 		return NULL;
165 
166 	memset(pvc, 0, sizeof(pvc_device));
167 	pvc->dlci = dlci;
168 	pvc->master = dev;
169 	pvc->next = *pvc_p;	/* Put it in the chain */
170 	*pvc_p = pvc;
171 	return pvc;
172 }
173 
174 
175 static inline int pvc_is_used(pvc_device *pvc)
176 {
177 	return pvc->main != NULL || pvc->ether != NULL;
178 }
179 
180 
181 static inline void pvc_carrier(int on, pvc_device *pvc)
182 {
183 	if (on) {
184 		if (pvc->main)
185 			if (!netif_carrier_ok(pvc->main))
186 				netif_carrier_on(pvc->main);
187 		if (pvc->ether)
188 			if (!netif_carrier_ok(pvc->ether))
189 				netif_carrier_on(pvc->ether);
190 	} else {
191 		if (pvc->main)
192 			if (netif_carrier_ok(pvc->main))
193 				netif_carrier_off(pvc->main);
194 		if (pvc->ether)
195 			if (netif_carrier_ok(pvc->ether))
196 				netif_carrier_off(pvc->ether);
197 	}
198 }
199 
200 
201 static inline void delete_unused_pvcs(hdlc_device *hdlc)
202 {
203 	pvc_device **pvc_p = &hdlc->state.fr.first_pvc;
204 
205 	while (*pvc_p) {
206 		if (!pvc_is_used(*pvc_p)) {
207 			pvc_device *pvc = *pvc_p;
208 			*pvc_p = pvc->next;
209 			kfree(pvc);
210 			continue;
211 		}
212 		pvc_p = &(*pvc_p)->next;
213 	}
214 }
215 
216 
217 static inline struct net_device** get_dev_p(pvc_device *pvc, int type)
218 {
219 	if (type == ARPHRD_ETHER)
220 		return &pvc->ether;
221 	else
222 		return &pvc->main;
223 }
224 
225 
226 static int fr_hard_header(struct sk_buff **skb_p, u16 dlci)
227 {
228 	u16 head_len;
229 	struct sk_buff *skb = *skb_p;
230 
231 	switch (skb->protocol) {
232 	case __constant_ntohs(NLPID_CCITT_ANSI_LMI):
233 		head_len = 4;
234 		skb_push(skb, head_len);
235 		skb->data[3] = NLPID_CCITT_ANSI_LMI;
236 		break;
237 
238 	case __constant_ntohs(NLPID_CISCO_LMI):
239 		head_len = 4;
240 		skb_push(skb, head_len);
241 		skb->data[3] = NLPID_CISCO_LMI;
242 		break;
243 
244 	case __constant_ntohs(ETH_P_IP):
245 		head_len = 4;
246 		skb_push(skb, head_len);
247 		skb->data[3] = NLPID_IP;
248 		break;
249 
250 	case __constant_ntohs(ETH_P_IPV6):
251 		head_len = 4;
252 		skb_push(skb, head_len);
253 		skb->data[3] = NLPID_IPV6;
254 		break;
255 
256 	case __constant_ntohs(ETH_P_802_3):
257 		head_len = 10;
258 		if (skb_headroom(skb) < head_len) {
259 			struct sk_buff *skb2 = skb_realloc_headroom(skb,
260 								    head_len);
261 			if (!skb2)
262 				return -ENOBUFS;
263 			dev_kfree_skb(skb);
264 			skb = *skb_p = skb2;
265 		}
266 		skb_push(skb, head_len);
267 		skb->data[3] = FR_PAD;
268 		skb->data[4] = NLPID_SNAP;
269 		skb->data[5] = FR_PAD;
270 		skb->data[6] = 0x80;
271 		skb->data[7] = 0xC2;
272 		skb->data[8] = 0x00;
273 		skb->data[9] = 0x07; /* bridged Ethernet frame w/out FCS */
274 		break;
275 
276 	default:
277 		head_len = 10;
278 		skb_push(skb, head_len);
279 		skb->data[3] = FR_PAD;
280 		skb->data[4] = NLPID_SNAP;
281 		skb->data[5] = FR_PAD;
282 		skb->data[6] = FR_PAD;
283 		skb->data[7] = FR_PAD;
284 		*(u16*)(skb->data + 8) = skb->protocol;
285 	}
286 
287 	dlci_to_q922(skb->data, dlci);
288 	skb->data[2] = FR_UI;
289 	return 0;
290 }
291 
292 
293 
294 static int pvc_open(struct net_device *dev)
295 {
296 	pvc_device *pvc = dev_to_pvc(dev);
297 
298 	if ((pvc->master->flags & IFF_UP) == 0)
299 		return -EIO;  /* Master must be UP in order to activate PVC */
300 
301 	if (pvc->open_count++ == 0) {
302 		hdlc_device *hdlc = dev_to_hdlc(pvc->master);
303 		if (hdlc->state.fr.settings.lmi == LMI_NONE)
304 			pvc->state.active = hdlc->carrier;
305 
306 		pvc_carrier(pvc->state.active, pvc);
307 		hdlc->state.fr.dce_changed = 1;
308 	}
309 	return 0;
310 }
311 
312 
313 
314 static int pvc_close(struct net_device *dev)
315 {
316 	pvc_device *pvc = dev_to_pvc(dev);
317 
318 	if (--pvc->open_count == 0) {
319 		hdlc_device *hdlc = dev_to_hdlc(pvc->master);
320 		if (hdlc->state.fr.settings.lmi == LMI_NONE)
321 			pvc->state.active = 0;
322 
323 		if (hdlc->state.fr.settings.dce) {
324 			hdlc->state.fr.dce_changed = 1;
325 			pvc->state.active = 0;
326 		}
327 	}
328 	return 0;
329 }
330 
331 
332 
333 int pvc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
334 {
335 	pvc_device *pvc = dev_to_pvc(dev);
336 	fr_proto_pvc_info info;
337 
338 	if (ifr->ifr_settings.type == IF_GET_PROTO) {
339 		if (dev->type == ARPHRD_ETHER)
340 			ifr->ifr_settings.type = IF_PROTO_FR_ETH_PVC;
341 		else
342 			ifr->ifr_settings.type = IF_PROTO_FR_PVC;
343 
344 		if (ifr->ifr_settings.size < sizeof(info)) {
345 			/* data size wanted */
346 			ifr->ifr_settings.size = sizeof(info);
347 			return -ENOBUFS;
348 		}
349 
350 		info.dlci = pvc->dlci;
351 		memcpy(info.master, pvc->master->name, IFNAMSIZ);
352 		if (copy_to_user(ifr->ifr_settings.ifs_ifsu.fr_pvc_info,
353 				 &info, sizeof(info)))
354 			return -EFAULT;
355 		return 0;
356 	}
357 
358 	return -EINVAL;
359 }
360 
361 
362 static inline struct net_device_stats *pvc_get_stats(struct net_device *dev)
363 {
364 	return netdev_priv(dev);
365 }
366 
367 
368 
369 static int pvc_xmit(struct sk_buff *skb, struct net_device *dev)
370 {
371 	pvc_device *pvc = dev_to_pvc(dev);
372 	struct net_device_stats *stats = pvc_get_stats(dev);
373 
374 	if (pvc->state.active) {
375 		if (dev->type == ARPHRD_ETHER) {
376 			int pad = ETH_ZLEN - skb->len;
377 			if (pad > 0) { /* Pad the frame with zeros */
378 				int len = skb->len;
379 				if (skb_tailroom(skb) < pad)
380 					if (pskb_expand_head(skb, 0, pad,
381 							     GFP_ATOMIC)) {
382 						stats->tx_dropped++;
383 						dev_kfree_skb(skb);
384 						return 0;
385 					}
386 				skb_put(skb, pad);
387 				memset(skb->data + len, 0, pad);
388 			}
389 			skb->protocol = __constant_htons(ETH_P_802_3);
390 		}
391 		if (!fr_hard_header(&skb, pvc->dlci)) {
392 			stats->tx_bytes += skb->len;
393 			stats->tx_packets++;
394 			if (pvc->state.fecn) /* TX Congestion counter */
395 				stats->tx_compressed++;
396 			skb->dev = pvc->master;
397 			dev_queue_xmit(skb);
398 			return 0;
399 		}
400 	}
401 
402 	stats->tx_dropped++;
403 	dev_kfree_skb(skb);
404 	return 0;
405 }
406 
407 
408 
409 static int pvc_change_mtu(struct net_device *dev, int new_mtu)
410 {
411 	if ((new_mtu < 68) || (new_mtu > HDLC_MAX_MTU))
412 		return -EINVAL;
413 	dev->mtu = new_mtu;
414 	return 0;
415 }
416 
417 
418 
419 static inline void fr_log_dlci_active(pvc_device *pvc)
420 {
421 	printk(KERN_INFO "%s: DLCI %d [%s%s%s]%s %s\n",
422 	       pvc->master->name,
423 	       pvc->dlci,
424 	       pvc->main ? pvc->main->name : "",
425 	       pvc->main && pvc->ether ? " " : "",
426 	       pvc->ether ? pvc->ether->name : "",
427 	       pvc->state.new ? " new" : "",
428 	       !pvc->state.exist ? "deleted" :
429 	       pvc->state.active ? "active" : "inactive");
430 }
431 
432 
433 
434 static inline u8 fr_lmi_nextseq(u8 x)
435 {
436 	x++;
437 	return x ? x : 1;
438 }
439 
440 
441 
442 static void fr_lmi_send(struct net_device *dev, int fullrep)
443 {
444 	hdlc_device *hdlc = dev_to_hdlc(dev);
445 	struct sk_buff *skb;
446 	pvc_device *pvc = hdlc->state.fr.first_pvc;
447 	int lmi = hdlc->state.fr.settings.lmi;
448 	int dce = hdlc->state.fr.settings.dce;
449 	int len = lmi == LMI_ANSI ? LMI_ANSI_LENGTH : LMI_CCITT_CISCO_LENGTH;
450 	int stat_len = (lmi == LMI_CISCO) ? 6 : 3;
451 	u8 *data;
452 	int i = 0;
453 
454 	if (dce && fullrep) {
455 		len += hdlc->state.fr.dce_pvc_count * (2 + stat_len);
456 		if (len > HDLC_MAX_MRU) {
457 			printk(KERN_WARNING "%s: Too many PVCs while sending "
458 			       "LMI full report\n", dev->name);
459 			return;
460 		}
461 	}
462 
463 	skb = dev_alloc_skb(len);
464 	if (!skb) {
465 		printk(KERN_WARNING "%s: Memory squeeze on fr_lmi_send()\n",
466 		       dev->name);
467 		return;
468 	}
469 	memset(skb->data, 0, len);
470 	skb_reserve(skb, 4);
471 	if (lmi == LMI_CISCO) {
472 		skb->protocol = __constant_htons(NLPID_CISCO_LMI);
473 		fr_hard_header(&skb, LMI_CISCO_DLCI);
474 	} else {
475 		skb->protocol = __constant_htons(NLPID_CCITT_ANSI_LMI);
476 		fr_hard_header(&skb, LMI_CCITT_ANSI_DLCI);
477 	}
478 	data = skb->tail;
479 	data[i++] = LMI_CALLREF;
480 	data[i++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
481 	if (lmi == LMI_ANSI)
482 		data[i++] = LMI_ANSI_LOCKSHIFT;
483 	data[i++] = lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
484 		LMI_ANSI_CISCO_REPTYPE;
485 	data[i++] = LMI_REPT_LEN;
486 	data[i++] = fullrep ? LMI_FULLREP : LMI_INTEGRITY;
487 	data[i++] = lmi == LMI_CCITT ? LMI_CCITT_ALIVE : LMI_ANSI_CISCO_ALIVE;
488 	data[i++] = LMI_INTEG_LEN;
489 	data[i++] = hdlc->state.fr.txseq =fr_lmi_nextseq(hdlc->state.fr.txseq);
490 	data[i++] = hdlc->state.fr.rxseq;
491 
492 	if (dce && fullrep) {
493 		while (pvc) {
494 			data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
495 				LMI_ANSI_CISCO_PVCSTAT;
496 			data[i++] = stat_len;
497 
498 			/* LMI start/restart */
499 			if (hdlc->state.fr.reliable && !pvc->state.exist) {
500 				pvc->state.exist = pvc->state.new = 1;
501 				fr_log_dlci_active(pvc);
502 			}
503 
504 			/* ifconfig PVC up */
505 			if (pvc->open_count && !pvc->state.active &&
506 			    pvc->state.exist && !pvc->state.new) {
507 				pvc_carrier(1, pvc);
508 				pvc->state.active = 1;
509 				fr_log_dlci_active(pvc);
510 			}
511 
512 			if (lmi == LMI_CISCO) {
513 				data[i] = pvc->dlci >> 8;
514 				data[i + 1] = pvc->dlci & 0xFF;
515 			} else {
516 				data[i] = (pvc->dlci >> 4) & 0x3F;
517 				data[i + 1] = ((pvc->dlci << 3) & 0x78) | 0x80;
518 				data[i + 2] = 0x80;
519 			}
520 
521 			if (pvc->state.new)
522 				data[i + 2] |= 0x08;
523 			else if (pvc->state.active)
524 				data[i + 2] |= 0x02;
525 
526 			i += stat_len;
527 			pvc = pvc->next;
528 		}
529 	}
530 
531 	skb_put(skb, i);
532 	skb->priority = TC_PRIO_CONTROL;
533 	skb->dev = dev;
534 	skb->nh.raw = skb->data;
535 
536 	dev_queue_xmit(skb);
537 }
538 
539 
540 
541 static void fr_set_link_state(int reliable, struct net_device *dev)
542 {
543 	hdlc_device *hdlc = dev_to_hdlc(dev);
544 	pvc_device *pvc = hdlc->state.fr.first_pvc;
545 
546 	hdlc->state.fr.reliable = reliable;
547 	if (reliable) {
548 		if (!netif_carrier_ok(dev))
549 			netif_carrier_on(dev);
550 
551 		hdlc->state.fr.n391cnt = 0; /* Request full status */
552 		hdlc->state.fr.dce_changed = 1;
553 
554 		if (hdlc->state.fr.settings.lmi == LMI_NONE) {
555 			while (pvc) {	/* Activate all PVCs */
556 				pvc_carrier(1, pvc);
557 				pvc->state.exist = pvc->state.active = 1;
558 				pvc->state.new = 0;
559 				pvc = pvc->next;
560 			}
561 		}
562 	} else {
563 		if (netif_carrier_ok(dev))
564 			netif_carrier_off(dev);
565 
566 		while (pvc) {		/* Deactivate all PVCs */
567 			pvc_carrier(0, pvc);
568 			pvc->state.exist = pvc->state.active = 0;
569 			pvc->state.new = 0;
570 			if (!hdlc->state.fr.settings.dce)
571 				pvc->state.bandwidth = 0;
572 			pvc = pvc->next;
573 		}
574 	}
575 }
576 
577 
578 
579 static void fr_timer(unsigned long arg)
580 {
581 	struct net_device *dev = (struct net_device *)arg;
582 	hdlc_device *hdlc = dev_to_hdlc(dev);
583 	int i, cnt = 0, reliable;
584 	u32 list;
585 
586 	if (hdlc->state.fr.settings.dce) {
587 		reliable = hdlc->state.fr.request &&
588 			time_before(jiffies, hdlc->state.fr.last_poll +
589 				    hdlc->state.fr.settings.t392 * HZ);
590 		hdlc->state.fr.request = 0;
591 	} else {
592 		hdlc->state.fr.last_errors <<= 1; /* Shift the list */
593 		if (hdlc->state.fr.request) {
594 			if (hdlc->state.fr.reliable)
595 				printk(KERN_INFO "%s: No LMI status reply "
596 				       "received\n", dev->name);
597 			hdlc->state.fr.last_errors |= 1;
598 		}
599 
600 		list = hdlc->state.fr.last_errors;
601 		for (i = 0; i < hdlc->state.fr.settings.n393; i++, list >>= 1)
602 			cnt += (list & 1);	/* errors count */
603 
604 		reliable = (cnt < hdlc->state.fr.settings.n392);
605 	}
606 
607 	if (hdlc->state.fr.reliable != reliable) {
608 		printk(KERN_INFO "%s: Link %sreliable\n", dev->name,
609 		       reliable ? "" : "un");
610 		fr_set_link_state(reliable, dev);
611 	}
612 
613 	if (hdlc->state.fr.settings.dce)
614 		hdlc->state.fr.timer.expires = jiffies +
615 			hdlc->state.fr.settings.t392 * HZ;
616 	else {
617 		if (hdlc->state.fr.n391cnt)
618 			hdlc->state.fr.n391cnt--;
619 
620 		fr_lmi_send(dev, hdlc->state.fr.n391cnt == 0);
621 
622 		hdlc->state.fr.last_poll = jiffies;
623 		hdlc->state.fr.request = 1;
624 		hdlc->state.fr.timer.expires = jiffies +
625 			hdlc->state.fr.settings.t391 * HZ;
626 	}
627 
628 	hdlc->state.fr.timer.function = fr_timer;
629 	hdlc->state.fr.timer.data = arg;
630 	add_timer(&hdlc->state.fr.timer);
631 }
632 
633 
634 
635 static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
636 {
637 	hdlc_device *hdlc = dev_to_hdlc(dev);
638 	pvc_device *pvc;
639 	u8 rxseq, txseq;
640 	int lmi = hdlc->state.fr.settings.lmi;
641 	int dce = hdlc->state.fr.settings.dce;
642 	int stat_len = (lmi == LMI_CISCO) ? 6 : 3, reptype, error, no_ram, i;
643 
644 	if (skb->len < (lmi == LMI_ANSI ? LMI_ANSI_LENGTH :
645 			LMI_CCITT_CISCO_LENGTH)) {
646 		printk(KERN_INFO "%s: Short LMI frame\n", dev->name);
647 		return 1;
648 	}
649 
650 	if (skb->data[3] != (lmi == LMI_CISCO ? NLPID_CISCO_LMI :
651 			     NLPID_CCITT_ANSI_LMI)) {
652 		printk(KERN_INFO "%s: Received non-LMI frame with LMI"
653 		       " DLCI\n", dev->name);
654 		return 1;
655 	}
656 
657 	if (skb->data[4] != LMI_CALLREF) {
658 		printk(KERN_INFO "%s: Invalid LMI Call reference (0x%02X)\n",
659 		       dev->name, skb->data[4]);
660 		return 1;
661 	}
662 
663 	if (skb->data[5] != (dce ? LMI_STATUS_ENQUIRY : LMI_STATUS)) {
664 		printk(KERN_INFO "%s: Invalid LMI Message type (0x%02X)\n",
665 		       dev->name, skb->data[5]);
666 		return 1;
667 	}
668 
669 	if (lmi == LMI_ANSI) {
670 		if (skb->data[6] != LMI_ANSI_LOCKSHIFT) {
671 			printk(KERN_INFO "%s: Not ANSI locking shift in LMI"
672 			       " message (0x%02X)\n", dev->name, skb->data[6]);
673 			return 1;
674 		}
675 		i = 7;
676 	} else
677 		i = 6;
678 
679 	if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
680 			     LMI_ANSI_CISCO_REPTYPE)) {
681 		printk(KERN_INFO "%s: Not an LMI Report type IE (0x%02X)\n",
682 		       dev->name, skb->data[i]);
683 		return 1;
684 	}
685 
686 	if (skb->data[++i] != LMI_REPT_LEN) {
687 		printk(KERN_INFO "%s: Invalid LMI Report type IE length"
688 		       " (%u)\n", dev->name, skb->data[i]);
689 		return 1;
690 	}
691 
692 	reptype = skb->data[++i];
693 	if (reptype != LMI_INTEGRITY && reptype != LMI_FULLREP) {
694 		printk(KERN_INFO "%s: Unsupported LMI Report type (0x%02X)\n",
695 		       dev->name, reptype);
696 		return 1;
697 	}
698 
699 	if (skb->data[++i] != (lmi == LMI_CCITT ? LMI_CCITT_ALIVE :
700 			       LMI_ANSI_CISCO_ALIVE)) {
701 		printk(KERN_INFO "%s: Not an LMI Link integrity verification"
702 		       " IE (0x%02X)\n", dev->name, skb->data[i]);
703 		return 1;
704 	}
705 
706 	if (skb->data[++i] != LMI_INTEG_LEN) {
707 		printk(KERN_INFO "%s: Invalid LMI Link integrity verification"
708 		       " IE length (%u)\n", dev->name, skb->data[i]);
709 		return 1;
710 	}
711 	i++;
712 
713 	hdlc->state.fr.rxseq = skb->data[i++]; /* TX sequence from peer */
714 	rxseq = skb->data[i++];	/* Should confirm our sequence */
715 
716 	txseq = hdlc->state.fr.txseq;
717 
718 	if (dce)
719 		hdlc->state.fr.last_poll = jiffies;
720 
721 	error = 0;
722 	if (!hdlc->state.fr.reliable)
723 		error = 1;
724 
725 	if (rxseq == 0 || rxseq != txseq) {
726 		hdlc->state.fr.n391cnt = 0; /* Ask for full report next time */
727 		error = 1;
728 	}
729 
730 	if (dce) {
731 		if (hdlc->state.fr.fullrep_sent && !error) {
732 /* Stop sending full report - the last one has been confirmed by DTE */
733 			hdlc->state.fr.fullrep_sent = 0;
734 			pvc = hdlc->state.fr.first_pvc;
735 			while (pvc) {
736 				if (pvc->state.new) {
737 					pvc->state.new = 0;
738 
739 /* Tell DTE that new PVC is now active */
740 					hdlc->state.fr.dce_changed = 1;
741 				}
742 				pvc = pvc->next;
743 			}
744 		}
745 
746 		if (hdlc->state.fr.dce_changed) {
747 			reptype = LMI_FULLREP;
748 			hdlc->state.fr.fullrep_sent = 1;
749 			hdlc->state.fr.dce_changed = 0;
750 		}
751 
752 		hdlc->state.fr.request = 1; /* got request */
753 		fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
754 		return 0;
755 	}
756 
757 	/* DTE */
758 
759 	hdlc->state.fr.request = 0; /* got response, no request pending */
760 
761 	if (error)
762 		return 0;
763 
764 	if (reptype != LMI_FULLREP)
765 		return 0;
766 
767 	pvc = hdlc->state.fr.first_pvc;
768 
769 	while (pvc) {
770 		pvc->state.deleted = 1;
771 		pvc = pvc->next;
772 	}
773 
774 	no_ram = 0;
775 	while (skb->len >= i + 2 + stat_len) {
776 		u16 dlci;
777 		u32 bw;
778 		unsigned int active, new;
779 
780 		if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
781 				       LMI_ANSI_CISCO_PVCSTAT)) {
782 			printk(KERN_INFO "%s: Not an LMI PVC status IE"
783 			       " (0x%02X)\n", dev->name, skb->data[i]);
784 			return 1;
785 		}
786 
787 		if (skb->data[++i] != stat_len) {
788 			printk(KERN_INFO "%s: Invalid LMI PVC status IE length"
789 			       " (%u)\n", dev->name, skb->data[i]);
790 			return 1;
791 		}
792 		i++;
793 
794 		new = !! (skb->data[i + 2] & 0x08);
795 		active = !! (skb->data[i + 2] & 0x02);
796 		if (lmi == LMI_CISCO) {
797 			dlci = (skb->data[i] << 8) | skb->data[i + 1];
798 			bw = (skb->data[i + 3] << 16) |
799 				(skb->data[i + 4] << 8) |
800 				(skb->data[i + 5]);
801 		} else {
802 			dlci = ((skb->data[i] & 0x3F) << 4) |
803 				((skb->data[i + 1] & 0x78) >> 3);
804 			bw = 0;
805 		}
806 
807 		pvc = add_pvc(dev, dlci);
808 
809 		if (!pvc && !no_ram) {
810 			printk(KERN_WARNING
811 			       "%s: Memory squeeze on fr_lmi_recv()\n",
812 			       dev->name);
813 			no_ram = 1;
814 		}
815 
816 		if (pvc) {
817 			pvc->state.exist = 1;
818 			pvc->state.deleted = 0;
819 			if (active != pvc->state.active ||
820 			    new != pvc->state.new ||
821 			    bw != pvc->state.bandwidth ||
822 			    !pvc->state.exist) {
823 				pvc->state.new = new;
824 				pvc->state.active = active;
825 				pvc->state.bandwidth = bw;
826 				pvc_carrier(active, pvc);
827 				fr_log_dlci_active(pvc);
828 			}
829 		}
830 
831 		i += stat_len;
832 	}
833 
834 	pvc = hdlc->state.fr.first_pvc;
835 
836 	while (pvc) {
837 		if (pvc->state.deleted && pvc->state.exist) {
838 			pvc_carrier(0, pvc);
839 			pvc->state.active = pvc->state.new = 0;
840 			pvc->state.exist = 0;
841 			pvc->state.bandwidth = 0;
842 			fr_log_dlci_active(pvc);
843 		}
844 		pvc = pvc->next;
845 	}
846 
847 	/* Next full report after N391 polls */
848 	hdlc->state.fr.n391cnt = hdlc->state.fr.settings.n391;
849 
850 	return 0;
851 }
852 
853 
854 
855 static int fr_rx(struct sk_buff *skb)
856 {
857 	struct net_device *ndev = skb->dev;
858 	hdlc_device *hdlc = dev_to_hdlc(ndev);
859 	fr_hdr *fh = (fr_hdr*)skb->data;
860 	u8 *data = skb->data;
861 	u16 dlci;
862 	pvc_device *pvc;
863 	struct net_device *dev = NULL;
864 
865 	if (skb->len <= 4 || fh->ea1 || data[2] != FR_UI)
866 		goto rx_error;
867 
868 	dlci = q922_to_dlci(skb->data);
869 
870 	if ((dlci == LMI_CCITT_ANSI_DLCI &&
871 	     (hdlc->state.fr.settings.lmi == LMI_ANSI ||
872 	      hdlc->state.fr.settings.lmi == LMI_CCITT)) ||
873 	    (dlci == LMI_CISCO_DLCI &&
874 	     hdlc->state.fr.settings.lmi == LMI_CISCO)) {
875 		if (fr_lmi_recv(ndev, skb))
876 			goto rx_error;
877 		dev_kfree_skb_any(skb);
878 		return NET_RX_SUCCESS;
879 	}
880 
881 	pvc = find_pvc(hdlc, dlci);
882 	if (!pvc) {
883 #ifdef DEBUG_PKT
884 		printk(KERN_INFO "%s: No PVC for received frame's DLCI %d\n",
885 		       ndev->name, dlci);
886 #endif
887 		dev_kfree_skb_any(skb);
888 		return NET_RX_DROP;
889 	}
890 
891 	if (pvc->state.fecn != fh->fecn) {
892 #ifdef DEBUG_ECN
893 		printk(KERN_DEBUG "%s: DLCI %d FECN O%s\n", ndev->name,
894 		       dlci, fh->fecn ? "N" : "FF");
895 #endif
896 		pvc->state.fecn ^= 1;
897 	}
898 
899 	if (pvc->state.becn != fh->becn) {
900 #ifdef DEBUG_ECN
901 		printk(KERN_DEBUG "%s: DLCI %d BECN O%s\n", ndev->name,
902 		       dlci, fh->becn ? "N" : "FF");
903 #endif
904 		pvc->state.becn ^= 1;
905 	}
906 
907 
908 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
909 		hdlc->stats.rx_dropped++;
910 		return NET_RX_DROP;
911 	}
912 
913 	if (data[3] == NLPID_IP) {
914 		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
915 		dev = pvc->main;
916 		skb->protocol = htons(ETH_P_IP);
917 
918 	} else if (data[3] == NLPID_IPV6) {
919 		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
920 		dev = pvc->main;
921 		skb->protocol = htons(ETH_P_IPV6);
922 
923 	} else if (skb->len > 10 && data[3] == FR_PAD &&
924 		   data[4] == NLPID_SNAP && data[5] == FR_PAD) {
925 		u16 oui = ntohs(*(u16*)(data + 6));
926 		u16 pid = ntohs(*(u16*)(data + 8));
927 		skb_pull(skb, 10);
928 
929 		switch ((((u32)oui) << 16) | pid) {
930 		case ETH_P_ARP: /* routed frame with SNAP */
931 		case ETH_P_IPX:
932 		case ETH_P_IP:	/* a long variant */
933 		case ETH_P_IPV6:
934 			dev = pvc->main;
935 			skb->protocol = htons(pid);
936 			break;
937 
938 		case 0x80C20007: /* bridged Ethernet frame */
939 			if ((dev = pvc->ether) != NULL)
940 				skb->protocol = eth_type_trans(skb, dev);
941 			break;
942 
943 		default:
944 			printk(KERN_INFO "%s: Unsupported protocol, OUI=%x "
945 			       "PID=%x\n", ndev->name, oui, pid);
946 			dev_kfree_skb_any(skb);
947 			return NET_RX_DROP;
948 		}
949 	} else {
950 		printk(KERN_INFO "%s: Unsupported protocol, NLPID=%x "
951 		       "length = %i\n", ndev->name, data[3], skb->len);
952 		dev_kfree_skb_any(skb);
953 		return NET_RX_DROP;
954 	}
955 
956 	if (dev) {
957 		struct net_device_stats *stats = pvc_get_stats(dev);
958 		stats->rx_packets++; /* PVC traffic */
959 		stats->rx_bytes += skb->len;
960 		if (pvc->state.becn)
961 			stats->rx_compressed++;
962 		skb->dev = dev;
963 		netif_rx(skb);
964 		return NET_RX_SUCCESS;
965 	} else {
966 		dev_kfree_skb_any(skb);
967 		return NET_RX_DROP;
968 	}
969 
970  rx_error:
971 	hdlc->stats.rx_errors++; /* Mark error */
972 	dev_kfree_skb_any(skb);
973 	return NET_RX_DROP;
974 }
975 
976 
977 
978 static void fr_start(struct net_device *dev)
979 {
980 	hdlc_device *hdlc = dev_to_hdlc(dev);
981 #ifdef DEBUG_LINK
982 	printk(KERN_DEBUG "fr_start\n");
983 #endif
984 	if (hdlc->state.fr.settings.lmi != LMI_NONE) {
985 		hdlc->state.fr.reliable = 0;
986 		hdlc->state.fr.dce_changed = 1;
987 		hdlc->state.fr.request = 0;
988 		hdlc->state.fr.fullrep_sent = 0;
989 		hdlc->state.fr.last_errors = 0xFFFFFFFF;
990 		hdlc->state.fr.n391cnt = 0;
991 		hdlc->state.fr.txseq = hdlc->state.fr.rxseq = 0;
992 
993 		init_timer(&hdlc->state.fr.timer);
994 		/* First poll after 1 s */
995 		hdlc->state.fr.timer.expires = jiffies + HZ;
996 		hdlc->state.fr.timer.function = fr_timer;
997 		hdlc->state.fr.timer.data = (unsigned long)dev;
998 		add_timer(&hdlc->state.fr.timer);
999 	} else
1000 		fr_set_link_state(1, dev);
1001 }
1002 
1003 
1004 
1005 static void fr_stop(struct net_device *dev)
1006 {
1007 	hdlc_device *hdlc = dev_to_hdlc(dev);
1008 #ifdef DEBUG_LINK
1009 	printk(KERN_DEBUG "fr_stop\n");
1010 #endif
1011 	if (hdlc->state.fr.settings.lmi != LMI_NONE)
1012 		del_timer_sync(&hdlc->state.fr.timer);
1013 	fr_set_link_state(0, dev);
1014 }
1015 
1016 
1017 
1018 static void fr_close(struct net_device *dev)
1019 {
1020 	hdlc_device *hdlc = dev_to_hdlc(dev);
1021 	pvc_device *pvc = hdlc->state.fr.first_pvc;
1022 
1023 	while (pvc) {		/* Shutdown all PVCs for this FRAD */
1024 		if (pvc->main)
1025 			dev_close(pvc->main);
1026 		if (pvc->ether)
1027 			dev_close(pvc->ether);
1028 		pvc = pvc->next;
1029 	}
1030 }
1031 
1032 static void dlci_setup(struct net_device *dev)
1033 {
1034 	dev->type = ARPHRD_DLCI;
1035 	dev->flags = IFF_POINTOPOINT;
1036 	dev->hard_header_len = 10;
1037 	dev->addr_len = 2;
1038 }
1039 
1040 static int fr_add_pvc(struct net_device *master, unsigned int dlci, int type)
1041 {
1042 	hdlc_device *hdlc = dev_to_hdlc(master);
1043 	pvc_device *pvc = NULL;
1044 	struct net_device *dev;
1045 	int result, used;
1046 	char * prefix = "pvc%d";
1047 
1048 	if (type == ARPHRD_ETHER)
1049 		prefix = "pvceth%d";
1050 
1051 	if ((pvc = add_pvc(master, dlci)) == NULL) {
1052 		printk(KERN_WARNING "%s: Memory squeeze on fr_add_pvc()\n",
1053 		       master->name);
1054 		return -ENOBUFS;
1055 	}
1056 
1057 	if (*get_dev_p(pvc, type))
1058 		return -EEXIST;
1059 
1060 	used = pvc_is_used(pvc);
1061 
1062 	if (type == ARPHRD_ETHER)
1063 		dev = alloc_netdev(sizeof(struct net_device_stats),
1064 				   "pvceth%d", ether_setup);
1065 	else
1066 		dev = alloc_netdev(sizeof(struct net_device_stats),
1067 				   "pvc%d", dlci_setup);
1068 
1069 	if (!dev) {
1070 		printk(KERN_WARNING "%s: Memory squeeze on fr_pvc()\n",
1071 		       master->name);
1072 		delete_unused_pvcs(hdlc);
1073 		return -ENOBUFS;
1074 	}
1075 
1076 	if (type == ARPHRD_ETHER) {
1077 		memcpy(dev->dev_addr, "\x00\x01", 2);
1078                 get_random_bytes(dev->dev_addr + 2, ETH_ALEN - 2);
1079 	} else {
1080 		*(u16*)dev->dev_addr = htons(dlci);
1081 		dlci_to_q922(dev->broadcast, dlci);
1082 	}
1083 	dev->hard_start_xmit = pvc_xmit;
1084 	dev->get_stats = pvc_get_stats;
1085 	dev->open = pvc_open;
1086 	dev->stop = pvc_close;
1087 	dev->do_ioctl = pvc_ioctl;
1088 	dev->change_mtu = pvc_change_mtu;
1089 	dev->mtu = HDLC_MAX_MTU;
1090 	dev->tx_queue_len = 0;
1091 	dev->priv = pvc;
1092 
1093 	result = dev_alloc_name(dev, dev->name);
1094 	if (result < 0) {
1095 		free_netdev(dev);
1096 		delete_unused_pvcs(hdlc);
1097 		return result;
1098 	}
1099 
1100 	if (register_netdevice(dev) != 0) {
1101 		free_netdev(dev);
1102 		delete_unused_pvcs(hdlc);
1103 		return -EIO;
1104 	}
1105 
1106 	dev->destructor = free_netdev;
1107 	*get_dev_p(pvc, type) = dev;
1108 	if (!used) {
1109 		hdlc->state.fr.dce_changed = 1;
1110 		hdlc->state.fr.dce_pvc_count++;
1111 	}
1112 	return 0;
1113 }
1114 
1115 
1116 
1117 static int fr_del_pvc(hdlc_device *hdlc, unsigned int dlci, int type)
1118 {
1119 	pvc_device *pvc;
1120 	struct net_device *dev;
1121 
1122 	if ((pvc = find_pvc(hdlc, dlci)) == NULL)
1123 		return -ENOENT;
1124 
1125 	if ((dev = *get_dev_p(pvc, type)) == NULL)
1126 		return -ENOENT;
1127 
1128 	if (dev->flags & IFF_UP)
1129 		return -EBUSY;		/* PVC in use */
1130 
1131 	unregister_netdevice(dev); /* the destructor will free_netdev(dev) */
1132 	*get_dev_p(pvc, type) = NULL;
1133 
1134 	if (!pvc_is_used(pvc)) {
1135 		hdlc->state.fr.dce_pvc_count--;
1136 		hdlc->state.fr.dce_changed = 1;
1137 	}
1138 	delete_unused_pvcs(hdlc);
1139 	return 0;
1140 }
1141 
1142 
1143 
1144 static void fr_destroy(hdlc_device *hdlc)
1145 {
1146 	pvc_device *pvc;
1147 
1148 	pvc = hdlc->state.fr.first_pvc;
1149 	hdlc->state.fr.first_pvc = NULL; /* All PVCs destroyed */
1150 	hdlc->state.fr.dce_pvc_count = 0;
1151 	hdlc->state.fr.dce_changed = 1;
1152 
1153 	while (pvc) {
1154 		pvc_device *next = pvc->next;
1155 		/* destructors will free_netdev() main and ether */
1156 		if (pvc->main)
1157 			unregister_netdevice(pvc->main);
1158 
1159 		if (pvc->ether)
1160 			unregister_netdevice(pvc->ether);
1161 
1162 		kfree(pvc);
1163 		pvc = next;
1164 	}
1165 }
1166 
1167 
1168 
1169 int hdlc_fr_ioctl(struct net_device *dev, struct ifreq *ifr)
1170 {
1171 	fr_proto __user *fr_s = ifr->ifr_settings.ifs_ifsu.fr;
1172 	const size_t size = sizeof(fr_proto);
1173 	fr_proto new_settings;
1174 	hdlc_device *hdlc = dev_to_hdlc(dev);
1175 	fr_proto_pvc pvc;
1176 	int result;
1177 
1178 	switch (ifr->ifr_settings.type) {
1179 	case IF_GET_PROTO:
1180 		ifr->ifr_settings.type = IF_PROTO_FR;
1181 		if (ifr->ifr_settings.size < size) {
1182 			ifr->ifr_settings.size = size; /* data size wanted */
1183 			return -ENOBUFS;
1184 		}
1185 		if (copy_to_user(fr_s, &hdlc->state.fr.settings, size))
1186 			return -EFAULT;
1187 		return 0;
1188 
1189 	case IF_PROTO_FR:
1190 		if(!capable(CAP_NET_ADMIN))
1191 			return -EPERM;
1192 
1193 		if(dev->flags & IFF_UP)
1194 			return -EBUSY;
1195 
1196 		if (copy_from_user(&new_settings, fr_s, size))
1197 			return -EFAULT;
1198 
1199 		if (new_settings.lmi == LMI_DEFAULT)
1200 			new_settings.lmi = LMI_ANSI;
1201 
1202 		if ((new_settings.lmi != LMI_NONE &&
1203 		     new_settings.lmi != LMI_ANSI &&
1204 		     new_settings.lmi != LMI_CCITT &&
1205 		     new_settings.lmi != LMI_CISCO) ||
1206 		    new_settings.t391 < 1 ||
1207 		    new_settings.t392 < 2 ||
1208 		    new_settings.n391 < 1 ||
1209 		    new_settings.n392 < 1 ||
1210 		    new_settings.n393 < new_settings.n392 ||
1211 		    new_settings.n393 > 32 ||
1212 		    (new_settings.dce != 0 &&
1213 		     new_settings.dce != 1))
1214 			return -EINVAL;
1215 
1216 		result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
1217 		if (result)
1218 			return result;
1219 
1220 		if (hdlc->proto.id != IF_PROTO_FR) {
1221 			hdlc_proto_detach(hdlc);
1222 			hdlc->state.fr.first_pvc = NULL;
1223 			hdlc->state.fr.dce_pvc_count = 0;
1224 		}
1225 		memcpy(&hdlc->state.fr.settings, &new_settings, size);
1226 		memset(&hdlc->proto, 0, sizeof(hdlc->proto));
1227 
1228 		hdlc->proto.close = fr_close;
1229 		hdlc->proto.start = fr_start;
1230 		hdlc->proto.stop = fr_stop;
1231 		hdlc->proto.detach = fr_destroy;
1232 		hdlc->proto.netif_rx = fr_rx;
1233 		hdlc->proto.id = IF_PROTO_FR;
1234 		dev->hard_start_xmit = hdlc->xmit;
1235 		dev->hard_header = NULL;
1236 		dev->type = ARPHRD_FRAD;
1237 		dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1238 		dev->addr_len = 0;
1239 		return 0;
1240 
1241 	case IF_PROTO_FR_ADD_PVC:
1242 	case IF_PROTO_FR_DEL_PVC:
1243 	case IF_PROTO_FR_ADD_ETH_PVC:
1244 	case IF_PROTO_FR_DEL_ETH_PVC:
1245 		if(!capable(CAP_NET_ADMIN))
1246 			return -EPERM;
1247 
1248 		if (copy_from_user(&pvc, ifr->ifr_settings.ifs_ifsu.fr_pvc,
1249 				   sizeof(fr_proto_pvc)))
1250 			return -EFAULT;
1251 
1252 		if (pvc.dlci <= 0 || pvc.dlci >= 1024)
1253 			return -EINVAL;	/* Only 10 bits, DLCI 0 reserved */
1254 
1255 		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC ||
1256 		    ifr->ifr_settings.type == IF_PROTO_FR_DEL_ETH_PVC)
1257 			result = ARPHRD_ETHER; /* bridged Ethernet device */
1258 		else
1259 			result = ARPHRD_DLCI;
1260 
1261 		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_PVC ||
1262 		    ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC)
1263 			return fr_add_pvc(dev, pvc.dlci, result);
1264 		else
1265 			return fr_del_pvc(hdlc, pvc.dlci, result);
1266 	}
1267 
1268 	return -EINVAL;
1269 }
1270