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
64#define LMI_CCITT_ANSI_DLCI	   0 /* LMI DLCI */
65#define LMI_CISCO_DLCI		1023
66
67#define LMI_CALLREF		0x00 /* Call Reference */
68#define LMI_ANSI_LOCKSHIFT	0x95 /* ANSI locking shift */
69#define LMI_ANSI_CISCO_REPTYPE	0x01 /* report type */
70#define LMI_CCITT_REPTYPE	0x51
71#define LMI_ANSI_CISCO_ALIVE	0x03 /* keep alive */
72#define LMI_CCITT_ALIVE		0x53
73#define LMI_ANSI_CISCO_PVCSTAT	0x07 /* PVC status */
74#define LMI_CCITT_PVCSTAT	0x57
75
76#define LMI_FULLREP		0x00 /* full report  */
77#define LMI_INTEGRITY		0x01 /* link integrity report */
78#define LMI_SINGLE		0x02 /* single PVC report */
79
80#define LMI_STATUS_ENQUIRY      0x75
81#define LMI_STATUS              0x7D /* reply */
82
83#define LMI_REPT_LEN               1 /* report type element length */
84#define LMI_INTEG_LEN              2 /* link integrity element length */
85
86#define LMI_CCITT_CISCO_LENGTH	  13 /* LMI frame lengths */
87#define LMI_ANSI_LENGTH		  14
88
89
90struct fr_hdr {
91#if defined(__LITTLE_ENDIAN_BITFIELD)
92	unsigned ea1:	1;
93	unsigned cr:	1;
94	unsigned dlcih:	6;
95
96	unsigned ea2:	1;
97	unsigned de:	1;
98	unsigned becn:	1;
99	unsigned fecn:	1;
100	unsigned dlcil:	4;
101#else
102	unsigned dlcih:	6;
103	unsigned cr:	1;
104	unsigned ea1:	1;
105
106	unsigned dlcil:	4;
107	unsigned fecn:	1;
108	unsigned becn:	1;
109	unsigned de:	1;
110	unsigned ea2:	1;
111#endif
112} __packed;
113
114
115struct pvc_device {
116	struct net_device *frad;
117	struct net_device *main;
118	struct net_device *ether;	/* bridged Ethernet interface	*/
119	struct pvc_device *next;	/* Sorted in ascending DLCI order */
120	int dlci;
121	int open_count;
122
123	struct {
124		unsigned int new: 1;
125		unsigned int active: 1;
126		unsigned int exist: 1;
127		unsigned int deleted: 1;
128		unsigned int fecn: 1;
129		unsigned int becn: 1;
130		unsigned int bandwidth;	/* Cisco LMI reporting only */
131	}state;
132};
133
134struct frad_state {
135	fr_proto settings;
136	struct pvc_device *first_pvc;
137	int dce_pvc_count;
138
139	struct timer_list timer;
140	struct net_device *dev;
141	unsigned long last_poll;
142	int reliable;
143	int dce_changed;
144	int request;
145	int fullrep_sent;
146	u32 last_errors; /* last errors bit list */
147	u8 n391cnt;
148	u8 txseq; /* TX sequence number */
149	u8 rxseq; /* RX sequence number */
150};
151
152
153static int fr_ioctl(struct net_device *dev, struct ifreq *ifr);
154
155
156static inline u16 q922_to_dlci(u8 *hdr)
157{
158	return ((hdr[0] & 0xFC) << 2) | ((hdr[1] & 0xF0) >> 4);
159}
160
161
162static inline void dlci_to_q922(u8 *hdr, u16 dlci)
163{
164	hdr[0] = (dlci >> 2) & 0xFC;
165	hdr[1] = ((dlci << 4) & 0xF0) | 0x01;
166}
167
168
169static inline struct frad_state* state(hdlc_device *hdlc)
170{
171	return(struct frad_state *)(hdlc->state);
172}
173
174
175static inline struct pvc_device *find_pvc(hdlc_device *hdlc, u16 dlci)
176{
177	struct pvc_device *pvc = state(hdlc)->first_pvc;
178
179	while (pvc) {
180		if (pvc->dlci == dlci)
181			return pvc;
182		if (pvc->dlci > dlci)
183			return NULL; /* the list is sorted */
184		pvc = pvc->next;
185	}
186
187	return NULL;
188}
189
190
191static struct pvc_device *add_pvc(struct net_device *dev, u16 dlci)
192{
193	hdlc_device *hdlc = dev_to_hdlc(dev);
194	struct pvc_device *pvc, **pvc_p = &state(hdlc)->first_pvc;
195
196	while (*pvc_p) {
197		if ((*pvc_p)->dlci == dlci)
198			return *pvc_p;
199		if ((*pvc_p)->dlci > dlci)
200			break;	/* the list is sorted */
201		pvc_p = &(*pvc_p)->next;
202	}
203
204	pvc = kzalloc(sizeof(*pvc), GFP_ATOMIC);
205#ifdef DEBUG_PVC
206	printk(KERN_DEBUG "add_pvc: allocated pvc %p, frad %p\n", pvc, dev);
207#endif
208	if (!pvc)
209		return NULL;
210
211	pvc->dlci = dlci;
212	pvc->frad = dev;
213	pvc->next = *pvc_p;	/* Put it in the chain */
214	*pvc_p = pvc;
215	return pvc;
216}
217
218
219static inline int pvc_is_used(struct pvc_device *pvc)
220{
221	return pvc->main || pvc->ether;
222}
223
224
225static inline void pvc_carrier(int on, struct pvc_device *pvc)
226{
227	if (on) {
228		if (pvc->main)
229			if (!netif_carrier_ok(pvc->main))
230				netif_carrier_on(pvc->main);
231		if (pvc->ether)
232			if (!netif_carrier_ok(pvc->ether))
233				netif_carrier_on(pvc->ether);
234	} else {
235		if (pvc->main)
236			if (netif_carrier_ok(pvc->main))
237				netif_carrier_off(pvc->main);
238		if (pvc->ether)
239			if (netif_carrier_ok(pvc->ether))
240				netif_carrier_off(pvc->ether);
241	}
242}
243
244
245static inline void delete_unused_pvcs(hdlc_device *hdlc)
246{
247	struct pvc_device **pvc_p = &state(hdlc)->first_pvc;
248
249	while (*pvc_p) {
250		if (!pvc_is_used(*pvc_p)) {
251			struct pvc_device *pvc = *pvc_p;
252#ifdef DEBUG_PVC
253			printk(KERN_DEBUG "freeing unused pvc: %p\n", pvc);
254#endif
255			*pvc_p = pvc->next;
256			kfree(pvc);
257			continue;
258		}
259		pvc_p = &(*pvc_p)->next;
260	}
261}
262
263
264static inline struct net_device **get_dev_p(struct pvc_device *pvc,
265					    int type)
266{
267	if (type == ARPHRD_ETHER)
268		return &pvc->ether;
269	else
270		return &pvc->main;
271}
272
273
274static int fr_hard_header(struct sk_buff *skb, u16 dlci)
275{
276	if (!skb->dev) { /* Control packets */
277		switch (dlci) {
278		case LMI_CCITT_ANSI_DLCI:
279			skb_push(skb, 4);
280			skb->data[3] = NLPID_CCITT_ANSI_LMI;
281			break;
282
283		case LMI_CISCO_DLCI:
284			skb_push(skb, 4);
285			skb->data[3] = NLPID_CISCO_LMI;
286			break;
287
288		default:
289			return -EINVAL;
290		}
291
292	} else if (skb->dev->type == ARPHRD_DLCI) {
293		switch (skb->protocol) {
294		case htons(ETH_P_IP):
295			skb_push(skb, 4);
296			skb->data[3] = NLPID_IP;
297			break;
298
299		case htons(ETH_P_IPV6):
300			skb_push(skb, 4);
301			skb->data[3] = NLPID_IPV6;
302			break;
303
304		default:
305			skb_push(skb, 10);
306			skb->data[3] = FR_PAD;
307			skb->data[4] = NLPID_SNAP;
308			/* OUI 00-00-00 indicates an Ethertype follows */
309			skb->data[5] = 0x00;
310			skb->data[6] = 0x00;
311			skb->data[7] = 0x00;
312			/* This should be an Ethertype: */
313			*(__be16 *)(skb->data + 8) = skb->protocol;
314		}
315
316	} else if (skb->dev->type == ARPHRD_ETHER) {
317		skb_push(skb, 10);
318		skb->data[3] = FR_PAD;
319		skb->data[4] = NLPID_SNAP;
320		/* OUI 00-80-C2 stands for the 802.1 organization */
321		skb->data[5] = 0x00;
322		skb->data[6] = 0x80;
323		skb->data[7] = 0xC2;
324		/* PID 00-07 stands for Ethernet frames without FCS */
325		skb->data[8] = 0x00;
326		skb->data[9] = 0x07;
327
328	} else {
329		return -EINVAL;
330	}
331
332	dlci_to_q922(skb->data, dlci);
333	skb->data[2] = FR_UI;
334	return 0;
335}
336
337
338
339static int pvc_open(struct net_device *dev)
340{
341	struct pvc_device *pvc = dev->ml_priv;
342
343	if ((pvc->frad->flags & IFF_UP) == 0)
344		return -EIO;  /* Frad must be UP in order to activate PVC */
345
346	if (pvc->open_count++ == 0) {
347		hdlc_device *hdlc = dev_to_hdlc(pvc->frad);
348		if (state(hdlc)->settings.lmi == LMI_NONE)
349			pvc->state.active = netif_carrier_ok(pvc->frad);
350
351		pvc_carrier(pvc->state.active, pvc);
352		state(hdlc)->dce_changed = 1;
353	}
354	return 0;
355}
356
357
358
359static int pvc_close(struct net_device *dev)
360{
361	struct pvc_device *pvc = dev->ml_priv;
362
363	if (--pvc->open_count == 0) {
364		hdlc_device *hdlc = dev_to_hdlc(pvc->frad);
365		if (state(hdlc)->settings.lmi == LMI_NONE)
366			pvc->state.active = 0;
367
368		if (state(hdlc)->settings.dce) {
369			state(hdlc)->dce_changed = 1;
370			pvc->state.active = 0;
371		}
372	}
373	return 0;
374}
375
376
377
378static int pvc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
379{
380	struct pvc_device *pvc = dev->ml_priv;
381	fr_proto_pvc_info info;
382
383	if (ifr->ifr_settings.type == IF_GET_PROTO) {
384		if (dev->type == ARPHRD_ETHER)
385			ifr->ifr_settings.type = IF_PROTO_FR_ETH_PVC;
386		else
387			ifr->ifr_settings.type = IF_PROTO_FR_PVC;
388
389		if (ifr->ifr_settings.size < sizeof(info)) {
390			/* data size wanted */
391			ifr->ifr_settings.size = sizeof(info);
392			return -ENOBUFS;
393		}
394
395		info.dlci = pvc->dlci;
396		memcpy(info.master, pvc->frad->name, IFNAMSIZ);
397		if (copy_to_user(ifr->ifr_settings.ifs_ifsu.fr_pvc_info,
398				 &info, sizeof(info)))
399			return -EFAULT;
400		return 0;
401	}
402
403	return -EINVAL;
404}
405
406static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev)
407{
408	struct pvc_device *pvc = dev->ml_priv;
409
410	if (!pvc->state.active)
411		goto drop;
412
413	if (dev->type == ARPHRD_ETHER) {
414		int pad = ETH_ZLEN - skb->len;
415
416		if (pad > 0) { /* Pad the frame with zeros */
417			if (__skb_pad(skb, pad, false))
418				goto drop;
419			skb_put(skb, pad);
420		}
421	}
422
423	/* We already requested the header space with dev->needed_headroom.
424	 * So this is just a protection in case the upper layer didn't take
425	 * dev->needed_headroom into consideration.
426	 */
427	if (skb_headroom(skb) < 10) {
428		struct sk_buff *skb2 = skb_realloc_headroom(skb, 10);
429
430		if (!skb2)
431			goto drop;
432		dev_kfree_skb(skb);
433		skb = skb2;
434	}
435
436	skb->dev = dev;
437	if (fr_hard_header(skb, pvc->dlci))
438		goto drop;
439
440	dev->stats.tx_bytes += skb->len;
441	dev->stats.tx_packets++;
442	if (pvc->state.fecn) /* TX Congestion counter */
443		dev->stats.tx_compressed++;
444	skb->dev = pvc->frad;
445	skb->protocol = htons(ETH_P_HDLC);
446	skb_reset_network_header(skb);
447	dev_queue_xmit(skb);
448	return NETDEV_TX_OK;
449
450drop:
451	dev->stats.tx_dropped++;
452	kfree_skb(skb);
453	return NETDEV_TX_OK;
454}
455
456static inline void fr_log_dlci_active(struct pvc_device *pvc)
457{
458	netdev_info(pvc->frad, "DLCI %d [%s%s%s]%s %s\n",
459		    pvc->dlci,
460		    pvc->main ? pvc->main->name : "",
461		    pvc->main && pvc->ether ? " " : "",
462		    pvc->ether ? pvc->ether->name : "",
463		    pvc->state.new ? " new" : "",
464		    !pvc->state.exist ? "deleted" :
465		    pvc->state.active ? "active" : "inactive");
466}
467
468
469
470static inline u8 fr_lmi_nextseq(u8 x)
471{
472	x++;
473	return x ? x : 1;
474}
475
476
477static void fr_lmi_send(struct net_device *dev, int fullrep)
478{
479	hdlc_device *hdlc = dev_to_hdlc(dev);
480	struct sk_buff *skb;
481	struct pvc_device *pvc = state(hdlc)->first_pvc;
482	int lmi = state(hdlc)->settings.lmi;
483	int dce = state(hdlc)->settings.dce;
484	int len = lmi == LMI_ANSI ? LMI_ANSI_LENGTH : LMI_CCITT_CISCO_LENGTH;
485	int stat_len = (lmi == LMI_CISCO) ? 6 : 3;
486	u8 *data;
487	int i = 0;
488
489	if (dce && fullrep) {
490		len += state(hdlc)->dce_pvc_count * (2 + stat_len);
491		if (len > HDLC_MAX_MRU) {
492			netdev_warn(dev, "Too many PVCs while sending LMI full report\n");
493			return;
494		}
495	}
496
497	skb = dev_alloc_skb(len);
498	if (!skb) {
499		netdev_warn(dev, "Memory squeeze on fr_lmi_send()\n");
500		return;
501	}
502	memset(skb->data, 0, len);
503	skb_reserve(skb, 4);
504	if (lmi == LMI_CISCO) {
505		fr_hard_header(skb, LMI_CISCO_DLCI);
506	} else {
507		fr_hard_header(skb, LMI_CCITT_ANSI_DLCI);
508	}
509	data = skb_tail_pointer(skb);
510	data[i++] = LMI_CALLREF;
511	data[i++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
512	if (lmi == LMI_ANSI)
513		data[i++] = LMI_ANSI_LOCKSHIFT;
514	data[i++] = lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
515		LMI_ANSI_CISCO_REPTYPE;
516	data[i++] = LMI_REPT_LEN;
517	data[i++] = fullrep ? LMI_FULLREP : LMI_INTEGRITY;
518	data[i++] = lmi == LMI_CCITT ? LMI_CCITT_ALIVE : LMI_ANSI_CISCO_ALIVE;
519	data[i++] = LMI_INTEG_LEN;
520	data[i++] = state(hdlc)->txseq =
521		fr_lmi_nextseq(state(hdlc)->txseq);
522	data[i++] = state(hdlc)->rxseq;
523
524	if (dce && fullrep) {
525		while (pvc) {
526			data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
527				LMI_ANSI_CISCO_PVCSTAT;
528			data[i++] = stat_len;
529
530			/* LMI start/restart */
531			if (state(hdlc)->reliable && !pvc->state.exist) {
532				pvc->state.exist = pvc->state.new = 1;
533				fr_log_dlci_active(pvc);
534			}
535
536			/* ifconfig PVC up */
537			if (pvc->open_count && !pvc->state.active &&
538			    pvc->state.exist && !pvc->state.new) {
539				pvc_carrier(1, pvc);
540				pvc->state.active = 1;
541				fr_log_dlci_active(pvc);
542			}
543
544			if (lmi == LMI_CISCO) {
545				data[i] = pvc->dlci >> 8;
546				data[i + 1] = pvc->dlci & 0xFF;
547			} else {
548				data[i] = (pvc->dlci >> 4) & 0x3F;
549				data[i + 1] = ((pvc->dlci << 3) & 0x78) | 0x80;
550				data[i + 2] = 0x80;
551			}
552
553			if (pvc->state.new)
554				data[i + 2] |= 0x08;
555			else if (pvc->state.active)
556				data[i + 2] |= 0x02;
557
558			i += stat_len;
559			pvc = pvc->next;
560		}
561	}
562
563	skb_put(skb, i);
564	skb->priority = TC_PRIO_CONTROL;
565	skb->dev = dev;
566	skb->protocol = htons(ETH_P_HDLC);
567	skb_reset_network_header(skb);
568
569	dev_queue_xmit(skb);
570}
571
572
573
574static void fr_set_link_state(int reliable, struct net_device *dev)
575{
576	hdlc_device *hdlc = dev_to_hdlc(dev);
577	struct pvc_device *pvc = state(hdlc)->first_pvc;
578
579	state(hdlc)->reliable = reliable;
580	if (reliable) {
581		netif_dormant_off(dev);
582		state(hdlc)->n391cnt = 0; /* Request full status */
583		state(hdlc)->dce_changed = 1;
584
585		if (state(hdlc)->settings.lmi == LMI_NONE) {
586			while (pvc) {	/* Activate all PVCs */
587				pvc_carrier(1, pvc);
588				pvc->state.exist = pvc->state.active = 1;
589				pvc->state.new = 0;
590				pvc = pvc->next;
591			}
592		}
593	} else {
594		netif_dormant_on(dev);
595		while (pvc) {		/* Deactivate all PVCs */
596			pvc_carrier(0, pvc);
597			pvc->state.exist = pvc->state.active = 0;
598			pvc->state.new = 0;
599			if (!state(hdlc)->settings.dce)
600				pvc->state.bandwidth = 0;
601			pvc = pvc->next;
602		}
603	}
604}
605
606
607static void fr_timer(struct timer_list *t)
608{
609	struct frad_state *st = from_timer(st, t, timer);
610	struct net_device *dev = st->dev;
611	hdlc_device *hdlc = dev_to_hdlc(dev);
612	int i, cnt = 0, reliable;
613	u32 list;
614
615	if (state(hdlc)->settings.dce) {
616		reliable = state(hdlc)->request &&
617			time_before(jiffies, state(hdlc)->last_poll +
618				    state(hdlc)->settings.t392 * HZ);
619		state(hdlc)->request = 0;
620	} else {
621		state(hdlc)->last_errors <<= 1; /* Shift the list */
622		if (state(hdlc)->request) {
623			if (state(hdlc)->reliable)
624				netdev_info(dev, "No LMI status reply received\n");
625			state(hdlc)->last_errors |= 1;
626		}
627
628		list = state(hdlc)->last_errors;
629		for (i = 0; i < state(hdlc)->settings.n393; i++, list >>= 1)
630			cnt += (list & 1);	/* errors count */
631
632		reliable = (cnt < state(hdlc)->settings.n392);
633	}
634
635	if (state(hdlc)->reliable != reliable) {
636		netdev_info(dev, "Link %sreliable\n", reliable ? "" : "un");
637		fr_set_link_state(reliable, dev);
638	}
639
640	if (state(hdlc)->settings.dce)
641		state(hdlc)->timer.expires = jiffies +
642			state(hdlc)->settings.t392 * HZ;
643	else {
644		if (state(hdlc)->n391cnt)
645			state(hdlc)->n391cnt--;
646
647		fr_lmi_send(dev, state(hdlc)->n391cnt == 0);
648
649		state(hdlc)->last_poll = jiffies;
650		state(hdlc)->request = 1;
651		state(hdlc)->timer.expires = jiffies +
652			state(hdlc)->settings.t391 * HZ;
653	}
654
655	add_timer(&state(hdlc)->timer);
656}
657
658
659static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
660{
661	hdlc_device *hdlc = dev_to_hdlc(dev);
662	struct pvc_device *pvc;
663	u8 rxseq, txseq;
664	int lmi = state(hdlc)->settings.lmi;
665	int dce = state(hdlc)->settings.dce;
666	int stat_len = (lmi == LMI_CISCO) ? 6 : 3, reptype, error, no_ram, i;
667
668	if (skb->len < (lmi == LMI_ANSI ? LMI_ANSI_LENGTH :
669			LMI_CCITT_CISCO_LENGTH)) {
670		netdev_info(dev, "Short LMI frame\n");
671		return 1;
672	}
673
674	if (skb->data[3] != (lmi == LMI_CISCO ? NLPID_CISCO_LMI :
675			     NLPID_CCITT_ANSI_LMI)) {
676		netdev_info(dev, "Received non-LMI frame with LMI DLCI\n");
677		return 1;
678	}
679
680	if (skb->data[4] != LMI_CALLREF) {
681		netdev_info(dev, "Invalid LMI Call reference (0x%02X)\n",
682			    skb->data[4]);
683		return 1;
684	}
685
686	if (skb->data[5] != (dce ? LMI_STATUS_ENQUIRY : LMI_STATUS)) {
687		netdev_info(dev, "Invalid LMI Message type (0x%02X)\n",
688			    skb->data[5]);
689		return 1;
690	}
691
692	if (lmi == LMI_ANSI) {
693		if (skb->data[6] != LMI_ANSI_LOCKSHIFT) {
694			netdev_info(dev, "Not ANSI locking shift in LMI message (0x%02X)\n",
695				    skb->data[6]);
696			return 1;
697		}
698		i = 7;
699	} else
700		i = 6;
701
702	if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
703			     LMI_ANSI_CISCO_REPTYPE)) {
704		netdev_info(dev, "Not an LMI Report type IE (0x%02X)\n",
705			    skb->data[i]);
706		return 1;
707	}
708
709	if (skb->data[++i] != LMI_REPT_LEN) {
710		netdev_info(dev, "Invalid LMI Report type IE length (%u)\n",
711			    skb->data[i]);
712		return 1;
713	}
714
715	reptype = skb->data[++i];
716	if (reptype != LMI_INTEGRITY && reptype != LMI_FULLREP) {
717		netdev_info(dev, "Unsupported LMI Report type (0x%02X)\n",
718			    reptype);
719		return 1;
720	}
721
722	if (skb->data[++i] != (lmi == LMI_CCITT ? LMI_CCITT_ALIVE :
723			       LMI_ANSI_CISCO_ALIVE)) {
724		netdev_info(dev, "Not an LMI Link integrity verification IE (0x%02X)\n",
725			    skb->data[i]);
726		return 1;
727	}
728
729	if (skb->data[++i] != LMI_INTEG_LEN) {
730		netdev_info(dev, "Invalid LMI Link integrity verification IE length (%u)\n",
731			    skb->data[i]);
732		return 1;
733	}
734	i++;
735
736	state(hdlc)->rxseq = skb->data[i++]; /* TX sequence from peer */
737	rxseq = skb->data[i++];	/* Should confirm our sequence */
738
739	txseq = state(hdlc)->txseq;
740
741	if (dce)
742		state(hdlc)->last_poll = jiffies;
743
744	error = 0;
745	if (!state(hdlc)->reliable)
746		error = 1;
747
748	if (rxseq == 0 || rxseq != txseq) { /* Ask for full report next time */
749		state(hdlc)->n391cnt = 0;
750		error = 1;
751	}
752
753	if (dce) {
754		if (state(hdlc)->fullrep_sent && !error) {
755/* Stop sending full report - the last one has been confirmed by DTE */
756			state(hdlc)->fullrep_sent = 0;
757			pvc = state(hdlc)->first_pvc;
758			while (pvc) {
759				if (pvc->state.new) {
760					pvc->state.new = 0;
761
762/* Tell DTE that new PVC is now active */
763					state(hdlc)->dce_changed = 1;
764				}
765				pvc = pvc->next;
766			}
767		}
768
769		if (state(hdlc)->dce_changed) {
770			reptype = LMI_FULLREP;
771			state(hdlc)->fullrep_sent = 1;
772			state(hdlc)->dce_changed = 0;
773		}
774
775		state(hdlc)->request = 1; /* got request */
776		fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
777		return 0;
778	}
779
780	/* DTE */
781
782	state(hdlc)->request = 0; /* got response, no request pending */
783
784	if (error)
785		return 0;
786
787	if (reptype != LMI_FULLREP)
788		return 0;
789
790	pvc = state(hdlc)->first_pvc;
791
792	while (pvc) {
793		pvc->state.deleted = 1;
794		pvc = pvc->next;
795	}
796
797	no_ram = 0;
798	while (skb->len >= i + 2 + stat_len) {
799		u16 dlci;
800		u32 bw;
801		unsigned int active, new;
802
803		if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
804				       LMI_ANSI_CISCO_PVCSTAT)) {
805			netdev_info(dev, "Not an LMI PVC status IE (0x%02X)\n",
806				    skb->data[i]);
807			return 1;
808		}
809
810		if (skb->data[++i] != stat_len) {
811			netdev_info(dev, "Invalid LMI PVC status IE length (%u)\n",
812				    skb->data[i]);
813			return 1;
814		}
815		i++;
816
817		new = !! (skb->data[i + 2] & 0x08);
818		active = !! (skb->data[i + 2] & 0x02);
819		if (lmi == LMI_CISCO) {
820			dlci = (skb->data[i] << 8) | skb->data[i + 1];
821			bw = (skb->data[i + 3] << 16) |
822				(skb->data[i + 4] << 8) |
823				(skb->data[i + 5]);
824		} else {
825			dlci = ((skb->data[i] & 0x3F) << 4) |
826				((skb->data[i + 1] & 0x78) >> 3);
827			bw = 0;
828		}
829
830		pvc = add_pvc(dev, dlci);
831
832		if (!pvc && !no_ram) {
833			netdev_warn(dev, "Memory squeeze on fr_lmi_recv()\n");
834			no_ram = 1;
835		}
836
837		if (pvc) {
838			pvc->state.exist = 1;
839			pvc->state.deleted = 0;
840			if (active != pvc->state.active ||
841			    new != pvc->state.new ||
842			    bw != pvc->state.bandwidth ||
843			    !pvc->state.exist) {
844				pvc->state.new = new;
845				pvc->state.active = active;
846				pvc->state.bandwidth = bw;
847				pvc_carrier(active, pvc);
848				fr_log_dlci_active(pvc);
849			}
850		}
851
852		i += stat_len;
853	}
854
855	pvc = state(hdlc)->first_pvc;
856
857	while (pvc) {
858		if (pvc->state.deleted && pvc->state.exist) {
859			pvc_carrier(0, pvc);
860			pvc->state.active = pvc->state.new = 0;
861			pvc->state.exist = 0;
862			pvc->state.bandwidth = 0;
863			fr_log_dlci_active(pvc);
864		}
865		pvc = pvc->next;
866	}
867
868	/* Next full report after N391 polls */
869	state(hdlc)->n391cnt = state(hdlc)->settings.n391;
870
871	return 0;
872}
873
874
875static int fr_rx(struct sk_buff *skb)
876{
877	struct net_device *frad = skb->dev;
878	hdlc_device *hdlc = dev_to_hdlc(frad);
879	struct fr_hdr *fh = (struct fr_hdr *)skb->data;
880	u8 *data = skb->data;
881	u16 dlci;
882	struct pvc_device *pvc;
883	struct net_device *dev = NULL;
884
885	if (skb->len <= 4 || fh->ea1 || data[2] != FR_UI)
886		goto rx_error;
887
888	dlci = q922_to_dlci(skb->data);
889
890	if ((dlci == LMI_CCITT_ANSI_DLCI &&
891	     (state(hdlc)->settings.lmi == LMI_ANSI ||
892	      state(hdlc)->settings.lmi == LMI_CCITT)) ||
893	    (dlci == LMI_CISCO_DLCI &&
894	     state(hdlc)->settings.lmi == LMI_CISCO)) {
895		if (fr_lmi_recv(frad, skb))
896			goto rx_error;
897		dev_kfree_skb_any(skb);
898		return NET_RX_SUCCESS;
899	}
900
901	pvc = find_pvc(hdlc, dlci);
902	if (!pvc) {
903#ifdef DEBUG_PKT
904		netdev_info(frad, "No PVC for received frame's DLCI %d\n",
905			    dlci);
906#endif
907		dev_kfree_skb_any(skb);
908		return NET_RX_DROP;
909	}
910
911	if (pvc->state.fecn != fh->fecn) {
912#ifdef DEBUG_ECN
913		printk(KERN_DEBUG "%s: DLCI %d FECN O%s\n", frad->name,
914		       dlci, fh->fecn ? "N" : "FF");
915#endif
916		pvc->state.fecn ^= 1;
917	}
918
919	if (pvc->state.becn != fh->becn) {
920#ifdef DEBUG_ECN
921		printk(KERN_DEBUG "%s: DLCI %d BECN O%s\n", frad->name,
922		       dlci, fh->becn ? "N" : "FF");
923#endif
924		pvc->state.becn ^= 1;
925	}
926
927
928	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
929		frad->stats.rx_dropped++;
930		return NET_RX_DROP;
931	}
932
933	if (data[3] == NLPID_IP) {
934		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
935		dev = pvc->main;
936		skb->protocol = htons(ETH_P_IP);
937
938	} else if (data[3] == NLPID_IPV6) {
939		skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
940		dev = pvc->main;
941		skb->protocol = htons(ETH_P_IPV6);
942
943	} else if (skb->len > 10 && data[3] == FR_PAD &&
944		   data[4] == NLPID_SNAP && data[5] == FR_PAD) {
945		u16 oui = ntohs(*(__be16*)(data + 6));
946		u16 pid = ntohs(*(__be16*)(data + 8));
947		skb_pull(skb, 10);
948
949		switch ((((u32)oui) << 16) | pid) {
950		case ETH_P_ARP: /* routed frame with SNAP */
951		case ETH_P_IPX:
952		case ETH_P_IP:	/* a long variant */
953		case ETH_P_IPV6:
954			dev = pvc->main;
955			skb->protocol = htons(pid);
956			break;
957
958		case 0x80C20007: /* bridged Ethernet frame */
959			if ((dev = pvc->ether) != NULL)
960				skb->protocol = eth_type_trans(skb, dev);
961			break;
962
963		default:
964			netdev_info(frad, "Unsupported protocol, OUI=%x PID=%x\n",
965				    oui, pid);
966			dev_kfree_skb_any(skb);
967			return NET_RX_DROP;
968		}
969	} else {
970		netdev_info(frad, "Unsupported protocol, NLPID=%x length=%i\n",
971			    data[3], skb->len);
972		dev_kfree_skb_any(skb);
973		return NET_RX_DROP;
974	}
975
976	if (dev) {
977		dev->stats.rx_packets++; /* PVC traffic */
978		dev->stats.rx_bytes += skb->len;
979		if (pvc->state.becn)
980			dev->stats.rx_compressed++;
981		skb->dev = dev;
982		netif_rx(skb);
983		return NET_RX_SUCCESS;
984	} else {
985		dev_kfree_skb_any(skb);
986		return NET_RX_DROP;
987	}
988
989 rx_error:
990	frad->stats.rx_errors++; /* Mark error */
991	dev_kfree_skb_any(skb);
992	return NET_RX_DROP;
993}
994
995
996
997static void fr_start(struct net_device *dev)
998{
999	hdlc_device *hdlc = dev_to_hdlc(dev);
1000#ifdef DEBUG_LINK
1001	printk(KERN_DEBUG "fr_start\n");
1002#endif
1003	if (state(hdlc)->settings.lmi != LMI_NONE) {
1004		state(hdlc)->reliable = 0;
1005		state(hdlc)->dce_changed = 1;
1006		state(hdlc)->request = 0;
1007		state(hdlc)->fullrep_sent = 0;
1008		state(hdlc)->last_errors = 0xFFFFFFFF;
1009		state(hdlc)->n391cnt = 0;
1010		state(hdlc)->txseq = state(hdlc)->rxseq = 0;
1011
1012		state(hdlc)->dev = dev;
1013		timer_setup(&state(hdlc)->timer, fr_timer, 0);
1014		/* First poll after 1 s */
1015		state(hdlc)->timer.expires = jiffies + HZ;
1016		add_timer(&state(hdlc)->timer);
1017	} else
1018		fr_set_link_state(1, dev);
1019}
1020
1021
1022static void fr_stop(struct net_device *dev)
1023{
1024	hdlc_device *hdlc = dev_to_hdlc(dev);
1025#ifdef DEBUG_LINK
1026	printk(KERN_DEBUG "fr_stop\n");
1027#endif
1028	if (state(hdlc)->settings.lmi != LMI_NONE)
1029		del_timer_sync(&state(hdlc)->timer);
1030	fr_set_link_state(0, dev);
1031}
1032
1033
1034static void fr_close(struct net_device *dev)
1035{
1036	hdlc_device *hdlc = dev_to_hdlc(dev);
1037	struct pvc_device *pvc = state(hdlc)->first_pvc;
1038
1039	while (pvc) {		/* Shutdown all PVCs for this FRAD */
1040		if (pvc->main)
1041			dev_close(pvc->main);
1042		if (pvc->ether)
1043			dev_close(pvc->ether);
1044		pvc = pvc->next;
1045	}
1046}
1047
1048
1049static void pvc_setup(struct net_device *dev)
1050{
1051	dev->type = ARPHRD_DLCI;
1052	dev->flags = IFF_POINTOPOINT;
1053	dev->hard_header_len = 0;
1054	dev->addr_len = 2;
1055	netif_keep_dst(dev);
1056}
1057
1058static const struct net_device_ops pvc_ops = {
1059	.ndo_open       = pvc_open,
1060	.ndo_stop       = pvc_close,
1061	.ndo_start_xmit = pvc_xmit,
1062	.ndo_do_ioctl   = pvc_ioctl,
1063};
1064
1065static int fr_add_pvc(struct net_device *frad, unsigned int dlci, int type)
1066{
1067	hdlc_device *hdlc = dev_to_hdlc(frad);
1068	struct pvc_device *pvc;
1069	struct net_device *dev;
1070	int used;
1071
1072	if ((pvc = add_pvc(frad, dlci)) == NULL) {
1073		netdev_warn(frad, "Memory squeeze on fr_add_pvc()\n");
1074		return -ENOBUFS;
1075	}
1076
1077	if (*get_dev_p(pvc, type))
1078		return -EEXIST;
1079
1080	used = pvc_is_used(pvc);
1081
1082	if (type == ARPHRD_ETHER)
1083		dev = alloc_netdev(0, "pvceth%d", NET_NAME_UNKNOWN,
1084				   ether_setup);
1085	else
1086		dev = alloc_netdev(0, "pvc%d", NET_NAME_UNKNOWN, pvc_setup);
1087
1088	if (!dev) {
1089		netdev_warn(frad, "Memory squeeze on fr_pvc()\n");
1090		delete_unused_pvcs(hdlc);
1091		return -ENOBUFS;
1092	}
1093
1094	if (type == ARPHRD_ETHER) {
1095		dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1096		eth_hw_addr_random(dev);
1097	} else {
1098		*(__be16*)dev->dev_addr = htons(dlci);
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
1124
1125
1126static int fr_del_pvc(hdlc_device *hdlc, unsigned int dlci, int type)
1127{
1128	struct pvc_device *pvc;
1129	struct net_device *dev;
1130
1131	if ((pvc = find_pvc(hdlc, dlci)) == NULL)
1132		return -ENOENT;
1133
1134	if ((dev = *get_dev_p(pvc, type)) == NULL)
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
1151
1152
1153static void fr_destroy(struct net_device *frad)
1154{
1155	hdlc_device *hdlc = dev_to_hdlc(frad);
1156	struct pvc_device *pvc = state(hdlc)->first_pvc;
1157	state(hdlc)->first_pvc = NULL; /* All PVCs destroyed */
1158	state(hdlc)->dce_pvc_count = 0;
1159	state(hdlc)->dce_changed = 1;
1160
1161	while (pvc) {
1162		struct pvc_device *next = pvc->next;
1163		/* destructors will free_netdev() main and ether */
1164		if (pvc->main)
1165			unregister_netdevice(pvc->main);
1166
1167		if (pvc->ether)
1168			unregister_netdevice(pvc->ether);
1169
1170		kfree(pvc);
1171		pvc = next;
1172	}
1173}
1174
1175
1176static struct hdlc_proto proto = {
1177	.close		= fr_close,
1178	.start		= fr_start,
1179	.stop		= fr_stop,
1180	.detach		= fr_destroy,
1181	.ioctl		= fr_ioctl,
1182	.netif_rx	= fr_rx,
1183	.module		= THIS_MODULE,
1184};
1185
1186
1187static int fr_ioctl(struct net_device *dev, struct ifreq *ifr)
1188{
1189	fr_proto __user *fr_s = ifr->ifr_settings.ifs_ifsu.fr;
1190	const size_t size = sizeof(fr_proto);
1191	fr_proto new_settings;
1192	hdlc_device *hdlc = dev_to_hdlc(dev);
1193	fr_proto_pvc pvc;
1194	int result;
1195
1196	switch (ifr->ifr_settings.type) {
1197	case IF_GET_PROTO:
1198		if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1199			return -EINVAL;
1200		ifr->ifr_settings.type = IF_PROTO_FR;
1201		if (ifr->ifr_settings.size < size) {
1202			ifr->ifr_settings.size = size; /* data size wanted */
1203			return -ENOBUFS;
1204		}
1205		if (copy_to_user(fr_s, &state(hdlc)->settings, size))
1206			return -EFAULT;
1207		return 0;
1208
1209	case IF_PROTO_FR:
1210		if (!capable(CAP_NET_ADMIN))
1211			return -EPERM;
1212
1213		if (dev->flags & IFF_UP)
1214			return -EBUSY;
1215
1216		if (copy_from_user(&new_settings, fr_s, size))
1217			return -EFAULT;
1218
1219		if (new_settings.lmi == LMI_DEFAULT)
1220			new_settings.lmi = LMI_ANSI;
1221
1222		if ((new_settings.lmi != LMI_NONE &&
1223		     new_settings.lmi != LMI_ANSI &&
1224		     new_settings.lmi != LMI_CCITT &&
1225		     new_settings.lmi != LMI_CISCO) ||
1226		    new_settings.t391 < 1 ||
1227		    new_settings.t392 < 2 ||
1228		    new_settings.n391 < 1 ||
1229		    new_settings.n392 < 1 ||
1230		    new_settings.n393 < new_settings.n392 ||
1231		    new_settings.n393 > 32 ||
1232		    (new_settings.dce != 0 &&
1233		     new_settings.dce != 1))
1234			return -EINVAL;
1235
1236		result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
1237		if (result)
1238			return result;
1239
1240		if (dev_to_hdlc(dev)->proto != &proto) { /* Different proto */
1241			result = attach_hdlc_protocol(dev, &proto,
1242						      sizeof(struct frad_state));
1243			if (result)
1244				return result;
1245			state(hdlc)->first_pvc = NULL;
1246			state(hdlc)->dce_pvc_count = 0;
1247		}
1248		memcpy(&state(hdlc)->settings, &new_settings, size);
1249		dev->type = ARPHRD_FRAD;
1250		call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
1251		return 0;
1252
1253	case IF_PROTO_FR_ADD_PVC:
1254	case IF_PROTO_FR_DEL_PVC:
1255	case IF_PROTO_FR_ADD_ETH_PVC:
1256	case IF_PROTO_FR_DEL_ETH_PVC:
1257		if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1258			return -EINVAL;
1259
1260		if (!capable(CAP_NET_ADMIN))
1261			return -EPERM;
1262
1263		if (copy_from_user(&pvc, ifr->ifr_settings.ifs_ifsu.fr_pvc,
1264				   sizeof(fr_proto_pvc)))
1265			return -EFAULT;
1266
1267		if (pvc.dlci <= 0 || pvc.dlci >= 1024)
1268			return -EINVAL;	/* Only 10 bits, DLCI 0 reserved */
1269
1270		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC ||
1271		    ifr->ifr_settings.type == IF_PROTO_FR_DEL_ETH_PVC)
1272			result = ARPHRD_ETHER; /* bridged Ethernet device */
1273		else
1274			result = ARPHRD_DLCI;
1275
1276		if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_PVC ||
1277		    ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC)
1278			return fr_add_pvc(dev, pvc.dlci, result);
1279		else
1280			return fr_del_pvc(hdlc, pvc.dlci, result);
1281	}
1282
1283	return -EINVAL;
1284}
1285
1286
1287static int __init mod_init(void)
1288{
1289	register_hdlc_protocol(&proto);
1290	return 0;
1291}
1292
1293
1294static void __exit mod_exit(void)
1295{
1296	unregister_hdlc_protocol(&proto);
1297}
1298
1299
1300module_init(mod_init);
1301module_exit(mod_exit);
1302
1303MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
1304MODULE_DESCRIPTION("Frame-Relay protocol support for generic HDLC");
1305MODULE_LICENSE("GPL v2");
1306