Merge tag 'xfs-5.13-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
[linux-2.6-microblaze.git] / drivers / net / wan / hdlc_fr.c
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
90 struct 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
115 struct 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
134 struct 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
153 static int fr_ioctl(struct net_device *dev, struct ifreq *ifr);
154
155
156 static inline u16 q922_to_dlci(u8 *hdr)
157 {
158         return ((hdr[0] & 0xFC) << 2) | ((hdr[1] & 0xF0) >> 4);
159 }
160
161
162 static 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
169 static inline struct frad_state* state(hdlc_device *hdlc)
170 {
171         return(struct frad_state *)(hdlc->state);
172 }
173
174
175 static 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
191 static 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
219 static inline int pvc_is_used(struct pvc_device *pvc)
220 {
221         return pvc->main || pvc->ether;
222 }
223
224
225 static 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
245 static 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
264 static 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
274 static 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
339 static 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
359 static 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
378 static 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
406 static 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 out;
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
450 drop:
451         kfree_skb(skb);
452 out:
453         dev->stats.tx_dropped++;
454         return NETDEV_TX_OK;
455 }
456
457 static inline void fr_log_dlci_active(struct pvc_device *pvc)
458 {
459         netdev_info(pvc->frad, "DLCI %d [%s%s%s]%s %s\n",
460                     pvc->dlci,
461                     pvc->main ? pvc->main->name : "",
462                     pvc->main && pvc->ether ? " " : "",
463                     pvc->ether ? pvc->ether->name : "",
464                     pvc->state.new ? " new" : "",
465                     !pvc->state.exist ? "deleted" :
466                     pvc->state.active ? "active" : "inactive");
467 }
468
469
470
471 static inline u8 fr_lmi_nextseq(u8 x)
472 {
473         x++;
474         return x ? x : 1;
475 }
476
477
478 static void fr_lmi_send(struct net_device *dev, int fullrep)
479 {
480         hdlc_device *hdlc = dev_to_hdlc(dev);
481         struct sk_buff *skb;
482         struct pvc_device *pvc = state(hdlc)->first_pvc;
483         int lmi = state(hdlc)->settings.lmi;
484         int dce = state(hdlc)->settings.dce;
485         int len = lmi == LMI_ANSI ? LMI_ANSI_LENGTH : LMI_CCITT_CISCO_LENGTH;
486         int stat_len = (lmi == LMI_CISCO) ? 6 : 3;
487         u8 *data;
488         int i = 0;
489
490         if (dce && fullrep) {
491                 len += state(hdlc)->dce_pvc_count * (2 + stat_len);
492                 if (len > HDLC_MAX_MRU) {
493                         netdev_warn(dev, "Too many PVCs while sending LMI full report\n");
494                         return;
495                 }
496         }
497
498         skb = dev_alloc_skb(len);
499         if (!skb) {
500                 netdev_warn(dev, "Memory squeeze on fr_lmi_send()\n");
501                 return;
502         }
503         memset(skb->data, 0, len);
504         skb_reserve(skb, 4);
505         if (lmi == LMI_CISCO) {
506                 fr_hard_header(skb, LMI_CISCO_DLCI);
507         } else {
508                 fr_hard_header(skb, LMI_CCITT_ANSI_DLCI);
509         }
510         data = skb_tail_pointer(skb);
511         data[i++] = LMI_CALLREF;
512         data[i++] = dce ? LMI_STATUS : LMI_STATUS_ENQUIRY;
513         if (lmi == LMI_ANSI)
514                 data[i++] = LMI_ANSI_LOCKSHIFT;
515         data[i++] = lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
516                 LMI_ANSI_CISCO_REPTYPE;
517         data[i++] = LMI_REPT_LEN;
518         data[i++] = fullrep ? LMI_FULLREP : LMI_INTEGRITY;
519         data[i++] = lmi == LMI_CCITT ? LMI_CCITT_ALIVE : LMI_ANSI_CISCO_ALIVE;
520         data[i++] = LMI_INTEG_LEN;
521         data[i++] = state(hdlc)->txseq =
522                 fr_lmi_nextseq(state(hdlc)->txseq);
523         data[i++] = state(hdlc)->rxseq;
524
525         if (dce && fullrep) {
526                 while (pvc) {
527                         data[i++] = lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
528                                 LMI_ANSI_CISCO_PVCSTAT;
529                         data[i++] = stat_len;
530
531                         /* LMI start/restart */
532                         if (state(hdlc)->reliable && !pvc->state.exist) {
533                                 pvc->state.exist = pvc->state.new = 1;
534                                 fr_log_dlci_active(pvc);
535                         }
536
537                         /* ifconfig PVC up */
538                         if (pvc->open_count && !pvc->state.active &&
539                             pvc->state.exist && !pvc->state.new) {
540                                 pvc_carrier(1, pvc);
541                                 pvc->state.active = 1;
542                                 fr_log_dlci_active(pvc);
543                         }
544
545                         if (lmi == LMI_CISCO) {
546                                 data[i] = pvc->dlci >> 8;
547                                 data[i + 1] = pvc->dlci & 0xFF;
548                         } else {
549                                 data[i] = (pvc->dlci >> 4) & 0x3F;
550                                 data[i + 1] = ((pvc->dlci << 3) & 0x78) | 0x80;
551                                 data[i + 2] = 0x80;
552                         }
553
554                         if (pvc->state.new)
555                                 data[i + 2] |= 0x08;
556                         else if (pvc->state.active)
557                                 data[i + 2] |= 0x02;
558
559                         i += stat_len;
560                         pvc = pvc->next;
561                 }
562         }
563
564         skb_put(skb, i);
565         skb->priority = TC_PRIO_CONTROL;
566         skb->dev = dev;
567         skb->protocol = htons(ETH_P_HDLC);
568         skb_reset_network_header(skb);
569
570         dev_queue_xmit(skb);
571 }
572
573
574
575 static void fr_set_link_state(int reliable, struct net_device *dev)
576 {
577         hdlc_device *hdlc = dev_to_hdlc(dev);
578         struct pvc_device *pvc = state(hdlc)->first_pvc;
579
580         state(hdlc)->reliable = reliable;
581         if (reliable) {
582                 netif_dormant_off(dev);
583                 state(hdlc)->n391cnt = 0; /* Request full status */
584                 state(hdlc)->dce_changed = 1;
585
586                 if (state(hdlc)->settings.lmi == LMI_NONE) {
587                         while (pvc) {   /* Activate all PVCs */
588                                 pvc_carrier(1, pvc);
589                                 pvc->state.exist = pvc->state.active = 1;
590                                 pvc->state.new = 0;
591                                 pvc = pvc->next;
592                         }
593                 }
594         } else {
595                 netif_dormant_on(dev);
596                 while (pvc) {           /* Deactivate all PVCs */
597                         pvc_carrier(0, pvc);
598                         pvc->state.exist = pvc->state.active = 0;
599                         pvc->state.new = 0;
600                         if (!state(hdlc)->settings.dce)
601                                 pvc->state.bandwidth = 0;
602                         pvc = pvc->next;
603                 }
604         }
605 }
606
607
608 static void fr_timer(struct timer_list *t)
609 {
610         struct frad_state *st = from_timer(st, t, timer);
611         struct net_device *dev = st->dev;
612         hdlc_device *hdlc = dev_to_hdlc(dev);
613         int i, cnt = 0, reliable;
614         u32 list;
615
616         if (state(hdlc)->settings.dce) {
617                 reliable = state(hdlc)->request &&
618                         time_before(jiffies, state(hdlc)->last_poll +
619                                     state(hdlc)->settings.t392 * HZ);
620                 state(hdlc)->request = 0;
621         } else {
622                 state(hdlc)->last_errors <<= 1; /* Shift the list */
623                 if (state(hdlc)->request) {
624                         if (state(hdlc)->reliable)
625                                 netdev_info(dev, "No LMI status reply received\n");
626                         state(hdlc)->last_errors |= 1;
627                 }
628
629                 list = state(hdlc)->last_errors;
630                 for (i = 0; i < state(hdlc)->settings.n393; i++, list >>= 1)
631                         cnt += (list & 1);      /* errors count */
632
633                 reliable = (cnt < state(hdlc)->settings.n392);
634         }
635
636         if (state(hdlc)->reliable != reliable) {
637                 netdev_info(dev, "Link %sreliable\n", reliable ? "" : "un");
638                 fr_set_link_state(reliable, dev);
639         }
640
641         if (state(hdlc)->settings.dce)
642                 state(hdlc)->timer.expires = jiffies +
643                         state(hdlc)->settings.t392 * HZ;
644         else {
645                 if (state(hdlc)->n391cnt)
646                         state(hdlc)->n391cnt--;
647
648                 fr_lmi_send(dev, state(hdlc)->n391cnt == 0);
649
650                 state(hdlc)->last_poll = jiffies;
651                 state(hdlc)->request = 1;
652                 state(hdlc)->timer.expires = jiffies +
653                         state(hdlc)->settings.t391 * HZ;
654         }
655
656         add_timer(&state(hdlc)->timer);
657 }
658
659
660 static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
661 {
662         hdlc_device *hdlc = dev_to_hdlc(dev);
663         struct pvc_device *pvc;
664         u8 rxseq, txseq;
665         int lmi = state(hdlc)->settings.lmi;
666         int dce = state(hdlc)->settings.dce;
667         int stat_len = (lmi == LMI_CISCO) ? 6 : 3, reptype, error, no_ram, i;
668
669         if (skb->len < (lmi == LMI_ANSI ? LMI_ANSI_LENGTH :
670                         LMI_CCITT_CISCO_LENGTH)) {
671                 netdev_info(dev, "Short LMI frame\n");
672                 return 1;
673         }
674
675         if (skb->data[3] != (lmi == LMI_CISCO ? NLPID_CISCO_LMI :
676                              NLPID_CCITT_ANSI_LMI)) {
677                 netdev_info(dev, "Received non-LMI frame with LMI DLCI\n");
678                 return 1;
679         }
680
681         if (skb->data[4] != LMI_CALLREF) {
682                 netdev_info(dev, "Invalid LMI Call reference (0x%02X)\n",
683                             skb->data[4]);
684                 return 1;
685         }
686
687         if (skb->data[5] != (dce ? LMI_STATUS_ENQUIRY : LMI_STATUS)) {
688                 netdev_info(dev, "Invalid LMI Message type (0x%02X)\n",
689                             skb->data[5]);
690                 return 1;
691         }
692
693         if (lmi == LMI_ANSI) {
694                 if (skb->data[6] != LMI_ANSI_LOCKSHIFT) {
695                         netdev_info(dev, "Not ANSI locking shift in LMI message (0x%02X)\n",
696                                     skb->data[6]);
697                         return 1;
698                 }
699                 i = 7;
700         } else
701                 i = 6;
702
703         if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_REPTYPE :
704                              LMI_ANSI_CISCO_REPTYPE)) {
705                 netdev_info(dev, "Not an LMI Report type IE (0x%02X)\n",
706                             skb->data[i]);
707                 return 1;
708         }
709
710         if (skb->data[++i] != LMI_REPT_LEN) {
711                 netdev_info(dev, "Invalid LMI Report type IE length (%u)\n",
712                             skb->data[i]);
713                 return 1;
714         }
715
716         reptype = skb->data[++i];
717         if (reptype != LMI_INTEGRITY && reptype != LMI_FULLREP) {
718                 netdev_info(dev, "Unsupported LMI Report type (0x%02X)\n",
719                             reptype);
720                 return 1;
721         }
722
723         if (skb->data[++i] != (lmi == LMI_CCITT ? LMI_CCITT_ALIVE :
724                                LMI_ANSI_CISCO_ALIVE)) {
725                 netdev_info(dev, "Not an LMI Link integrity verification IE (0x%02X)\n",
726                             skb->data[i]);
727                 return 1;
728         }
729
730         if (skb->data[++i] != LMI_INTEG_LEN) {
731                 netdev_info(dev, "Invalid LMI Link integrity verification IE length (%u)\n",
732                             skb->data[i]);
733                 return 1;
734         }
735         i++;
736
737         state(hdlc)->rxseq = skb->data[i++]; /* TX sequence from peer */
738         rxseq = skb->data[i++]; /* Should confirm our sequence */
739
740         txseq = state(hdlc)->txseq;
741
742         if (dce)
743                 state(hdlc)->last_poll = jiffies;
744
745         error = 0;
746         if (!state(hdlc)->reliable)
747                 error = 1;
748
749         if (rxseq == 0 || rxseq != txseq) { /* Ask for full report next time */
750                 state(hdlc)->n391cnt = 0;
751                 error = 1;
752         }
753
754         if (dce) {
755                 if (state(hdlc)->fullrep_sent && !error) {
756 /* Stop sending full report - the last one has been confirmed by DTE */
757                         state(hdlc)->fullrep_sent = 0;
758                         pvc = state(hdlc)->first_pvc;
759                         while (pvc) {
760                                 if (pvc->state.new) {
761                                         pvc->state.new = 0;
762
763 /* Tell DTE that new PVC is now active */
764                                         state(hdlc)->dce_changed = 1;
765                                 }
766                                 pvc = pvc->next;
767                         }
768                 }
769
770                 if (state(hdlc)->dce_changed) {
771                         reptype = LMI_FULLREP;
772                         state(hdlc)->fullrep_sent = 1;
773                         state(hdlc)->dce_changed = 0;
774                 }
775
776                 state(hdlc)->request = 1; /* got request */
777                 fr_lmi_send(dev, reptype == LMI_FULLREP ? 1 : 0);
778                 return 0;
779         }
780
781         /* DTE */
782
783         state(hdlc)->request = 0; /* got response, no request pending */
784
785         if (error)
786                 return 0;
787
788         if (reptype != LMI_FULLREP)
789                 return 0;
790
791         pvc = state(hdlc)->first_pvc;
792
793         while (pvc) {
794                 pvc->state.deleted = 1;
795                 pvc = pvc->next;
796         }
797
798         no_ram = 0;
799         while (skb->len >= i + 2 + stat_len) {
800                 u16 dlci;
801                 u32 bw;
802                 unsigned int active, new;
803
804                 if (skb->data[i] != (lmi == LMI_CCITT ? LMI_CCITT_PVCSTAT :
805                                        LMI_ANSI_CISCO_PVCSTAT)) {
806                         netdev_info(dev, "Not an LMI PVC status IE (0x%02X)\n",
807                                     skb->data[i]);
808                         return 1;
809                 }
810
811                 if (skb->data[++i] != stat_len) {
812                         netdev_info(dev, "Invalid LMI PVC status IE length (%u)\n",
813                                     skb->data[i]);
814                         return 1;
815                 }
816                 i++;
817
818                 new = !! (skb->data[i + 2] & 0x08);
819                 active = !! (skb->data[i + 2] & 0x02);
820                 if (lmi == LMI_CISCO) {
821                         dlci = (skb->data[i] << 8) | skb->data[i + 1];
822                         bw = (skb->data[i + 3] << 16) |
823                                 (skb->data[i + 4] << 8) |
824                                 (skb->data[i + 5]);
825                 } else {
826                         dlci = ((skb->data[i] & 0x3F) << 4) |
827                                 ((skb->data[i + 1] & 0x78) >> 3);
828                         bw = 0;
829                 }
830
831                 pvc = add_pvc(dev, dlci);
832
833                 if (!pvc && !no_ram) {
834                         netdev_warn(dev, "Memory squeeze on fr_lmi_recv()\n");
835                         no_ram = 1;
836                 }
837
838                 if (pvc) {
839                         pvc->state.exist = 1;
840                         pvc->state.deleted = 0;
841                         if (active != pvc->state.active ||
842                             new != pvc->state.new ||
843                             bw != pvc->state.bandwidth ||
844                             !pvc->state.exist) {
845                                 pvc->state.new = new;
846                                 pvc->state.active = active;
847                                 pvc->state.bandwidth = bw;
848                                 pvc_carrier(active, pvc);
849                                 fr_log_dlci_active(pvc);
850                         }
851                 }
852
853                 i += stat_len;
854         }
855
856         pvc = state(hdlc)->first_pvc;
857
858         while (pvc) {
859                 if (pvc->state.deleted && pvc->state.exist) {
860                         pvc_carrier(0, pvc);
861                         pvc->state.active = pvc->state.new = 0;
862                         pvc->state.exist = 0;
863                         pvc->state.bandwidth = 0;
864                         fr_log_dlci_active(pvc);
865                 }
866                 pvc = pvc->next;
867         }
868
869         /* Next full report after N391 polls */
870         state(hdlc)->n391cnt = state(hdlc)->settings.n391;
871
872         return 0;
873 }
874
875 static int fr_snap_parse(struct sk_buff *skb, struct pvc_device *pvc)
876 {
877         /* OUI 00-00-00 indicates an Ethertype follows */
878         if (skb->data[0] == 0x00 &&
879             skb->data[1] == 0x00 &&
880             skb->data[2] == 0x00) {
881                 if (!pvc->main)
882                         return -1;
883                 skb->dev = pvc->main;
884                 skb->protocol = *(__be16 *)(skb->data + 3); /* Ethertype */
885                 skb_pull(skb, 5);
886                 skb_reset_mac_header(skb);
887                 return 0;
888
889         /* OUI 00-80-C2 stands for the 802.1 organization */
890         } else if (skb->data[0] == 0x00 &&
891                    skb->data[1] == 0x80 &&
892                    skb->data[2] == 0xC2) {
893                 /* PID 00-07 stands for Ethernet frames without FCS */
894                 if (skb->data[3] == 0x00 &&
895                     skb->data[4] == 0x07) {
896                         if (!pvc->ether)
897                                 return -1;
898                         skb_pull(skb, 5);
899                         if (skb->len < ETH_HLEN)
900                                 return -1;
901                         skb->protocol = eth_type_trans(skb, pvc->ether);
902                         return 0;
903
904                 /* PID unsupported */
905                 } else {
906                         return -1;
907                 }
908
909         /* OUI unsupported */
910         } else {
911                 return -1;
912         }
913 }
914
915 static int fr_rx(struct sk_buff *skb)
916 {
917         struct net_device *frad = skb->dev;
918         hdlc_device *hdlc = dev_to_hdlc(frad);
919         struct fr_hdr *fh = (struct fr_hdr *)skb->data;
920         u8 *data = skb->data;
921         u16 dlci;
922         struct pvc_device *pvc;
923         struct net_device *dev;
924
925         if (skb->len < 4 || fh->ea1 || !fh->ea2 || data[2] != FR_UI)
926                 goto rx_error;
927
928         dlci = q922_to_dlci(skb->data);
929
930         if ((dlci == LMI_CCITT_ANSI_DLCI &&
931              (state(hdlc)->settings.lmi == LMI_ANSI ||
932               state(hdlc)->settings.lmi == LMI_CCITT)) ||
933             (dlci == LMI_CISCO_DLCI &&
934              state(hdlc)->settings.lmi == LMI_CISCO)) {
935                 if (fr_lmi_recv(frad, skb))
936                         goto rx_error;
937                 dev_kfree_skb_any(skb);
938                 return NET_RX_SUCCESS;
939         }
940
941         pvc = find_pvc(hdlc, dlci);
942         if (!pvc) {
943 #ifdef DEBUG_PKT
944                 netdev_info(frad, "No PVC for received frame's DLCI %d\n",
945                             dlci);
946 #endif
947                 goto rx_drop;
948         }
949
950         if (pvc->state.fecn != fh->fecn) {
951 #ifdef DEBUG_ECN
952                 printk(KERN_DEBUG "%s: DLCI %d FECN O%s\n", frad->name,
953                        dlci, fh->fecn ? "N" : "FF");
954 #endif
955                 pvc->state.fecn ^= 1;
956         }
957
958         if (pvc->state.becn != fh->becn) {
959 #ifdef DEBUG_ECN
960                 printk(KERN_DEBUG "%s: DLCI %d BECN O%s\n", frad->name,
961                        dlci, fh->becn ? "N" : "FF");
962 #endif
963                 pvc->state.becn ^= 1;
964         }
965
966
967         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
968                 frad->stats.rx_dropped++;
969                 return NET_RX_DROP;
970         }
971
972         if (data[3] == NLPID_IP) {
973                 if (!pvc->main)
974                         goto rx_drop;
975                 skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
976                 skb->dev = pvc->main;
977                 skb->protocol = htons(ETH_P_IP);
978                 skb_reset_mac_header(skb);
979
980         } else if (data[3] == NLPID_IPV6) {
981                 if (!pvc->main)
982                         goto rx_drop;
983                 skb_pull(skb, 4); /* Remove 4-byte header (hdr, UI, NLPID) */
984                 skb->dev = pvc->main;
985                 skb->protocol = htons(ETH_P_IPV6);
986                 skb_reset_mac_header(skb);
987
988         } else if (data[3] == FR_PAD) {
989                 if (skb->len < 5)
990                         goto rx_error;
991                 if (data[4] == NLPID_SNAP) { /* A SNAP header follows */
992                         skb_pull(skb, 5);
993                         if (skb->len < 5) /* Incomplete SNAP header */
994                                 goto rx_error;
995                         if (fr_snap_parse(skb, pvc))
996                                 goto rx_drop;
997                 } else {
998                         goto rx_drop;
999                 }
1000
1001         } else {
1002                 netdev_info(frad, "Unsupported protocol, NLPID=%x length=%i\n",
1003                             data[3], skb->len);
1004                 goto rx_drop;
1005         }
1006
1007         dev = skb->dev;
1008         dev->stats.rx_packets++; /* PVC traffic */
1009         dev->stats.rx_bytes += skb->len;
1010         if (pvc->state.becn)
1011                 dev->stats.rx_compressed++;
1012         netif_rx(skb);
1013         return NET_RX_SUCCESS;
1014
1015 rx_error:
1016         frad->stats.rx_errors++; /* Mark error */
1017 rx_drop:
1018         dev_kfree_skb_any(skb);
1019         return NET_RX_DROP;
1020 }
1021
1022
1023
1024 static void fr_start(struct net_device *dev)
1025 {
1026         hdlc_device *hdlc = dev_to_hdlc(dev);
1027 #ifdef DEBUG_LINK
1028         printk(KERN_DEBUG "fr_start\n");
1029 #endif
1030         if (state(hdlc)->settings.lmi != LMI_NONE) {
1031                 state(hdlc)->reliable = 0;
1032                 state(hdlc)->dce_changed = 1;
1033                 state(hdlc)->request = 0;
1034                 state(hdlc)->fullrep_sent = 0;
1035                 state(hdlc)->last_errors = 0xFFFFFFFF;
1036                 state(hdlc)->n391cnt = 0;
1037                 state(hdlc)->txseq = state(hdlc)->rxseq = 0;
1038
1039                 state(hdlc)->dev = dev;
1040                 timer_setup(&state(hdlc)->timer, fr_timer, 0);
1041                 /* First poll after 1 s */
1042                 state(hdlc)->timer.expires = jiffies + HZ;
1043                 add_timer(&state(hdlc)->timer);
1044         } else
1045                 fr_set_link_state(1, dev);
1046 }
1047
1048
1049 static void fr_stop(struct net_device *dev)
1050 {
1051         hdlc_device *hdlc = dev_to_hdlc(dev);
1052 #ifdef DEBUG_LINK
1053         printk(KERN_DEBUG "fr_stop\n");
1054 #endif
1055         if (state(hdlc)->settings.lmi != LMI_NONE)
1056                 del_timer_sync(&state(hdlc)->timer);
1057         fr_set_link_state(0, dev);
1058 }
1059
1060
1061 static void fr_close(struct net_device *dev)
1062 {
1063         hdlc_device *hdlc = dev_to_hdlc(dev);
1064         struct pvc_device *pvc = state(hdlc)->first_pvc;
1065
1066         while (pvc) {           /* Shutdown all PVCs for this FRAD */
1067                 if (pvc->main)
1068                         dev_close(pvc->main);
1069                 if (pvc->ether)
1070                         dev_close(pvc->ether);
1071                 pvc = pvc->next;
1072         }
1073 }
1074
1075
1076 static void pvc_setup(struct net_device *dev)
1077 {
1078         dev->type = ARPHRD_DLCI;
1079         dev->flags = IFF_POINTOPOINT;
1080         dev->hard_header_len = 0;
1081         dev->addr_len = 2;
1082         netif_keep_dst(dev);
1083 }
1084
1085 static const struct net_device_ops pvc_ops = {
1086         .ndo_open       = pvc_open,
1087         .ndo_stop       = pvc_close,
1088         .ndo_start_xmit = pvc_xmit,
1089         .ndo_do_ioctl   = pvc_ioctl,
1090 };
1091
1092 static int fr_add_pvc(struct net_device *frad, unsigned int dlci, int type)
1093 {
1094         hdlc_device *hdlc = dev_to_hdlc(frad);
1095         struct pvc_device *pvc;
1096         struct net_device *dev;
1097         int used;
1098
1099         if ((pvc = add_pvc(frad, dlci)) == NULL) {
1100                 netdev_warn(frad, "Memory squeeze on fr_add_pvc()\n");
1101                 return -ENOBUFS;
1102         }
1103
1104         if (*get_dev_p(pvc, type))
1105                 return -EEXIST;
1106
1107         used = pvc_is_used(pvc);
1108
1109         if (type == ARPHRD_ETHER)
1110                 dev = alloc_netdev(0, "pvceth%d", NET_NAME_UNKNOWN,
1111                                    ether_setup);
1112         else
1113                 dev = alloc_netdev(0, "pvc%d", NET_NAME_UNKNOWN, pvc_setup);
1114
1115         if (!dev) {
1116                 netdev_warn(frad, "Memory squeeze on fr_pvc()\n");
1117                 delete_unused_pvcs(hdlc);
1118                 return -ENOBUFS;
1119         }
1120
1121         if (type == ARPHRD_ETHER) {
1122                 dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1123                 eth_hw_addr_random(dev);
1124         } else {
1125                 *(__be16*)dev->dev_addr = htons(dlci);
1126                 dlci_to_q922(dev->broadcast, dlci);
1127         }
1128         dev->netdev_ops = &pvc_ops;
1129         dev->mtu = HDLC_MAX_MTU;
1130         dev->min_mtu = 68;
1131         dev->max_mtu = HDLC_MAX_MTU;
1132         dev->needed_headroom = 10;
1133         dev->priv_flags |= IFF_NO_QUEUE;
1134         dev->ml_priv = pvc;
1135
1136         if (register_netdevice(dev) != 0) {
1137                 free_netdev(dev);
1138                 delete_unused_pvcs(hdlc);
1139                 return -EIO;
1140         }
1141
1142         dev->needs_free_netdev = true;
1143         *get_dev_p(pvc, type) = dev;
1144         if (!used) {
1145                 state(hdlc)->dce_changed = 1;
1146                 state(hdlc)->dce_pvc_count++;
1147         }
1148         return 0;
1149 }
1150
1151
1152
1153 static int fr_del_pvc(hdlc_device *hdlc, unsigned int dlci, int type)
1154 {
1155         struct pvc_device *pvc;
1156         struct net_device *dev;
1157
1158         if ((pvc = find_pvc(hdlc, dlci)) == NULL)
1159                 return -ENOENT;
1160
1161         if ((dev = *get_dev_p(pvc, type)) == NULL)
1162                 return -ENOENT;
1163
1164         if (dev->flags & IFF_UP)
1165                 return -EBUSY;          /* PVC in use */
1166
1167         unregister_netdevice(dev); /* the destructor will free_netdev(dev) */
1168         *get_dev_p(pvc, type) = NULL;
1169
1170         if (!pvc_is_used(pvc)) {
1171                 state(hdlc)->dce_pvc_count--;
1172                 state(hdlc)->dce_changed = 1;
1173         }
1174         delete_unused_pvcs(hdlc);
1175         return 0;
1176 }
1177
1178
1179
1180 static void fr_destroy(struct net_device *frad)
1181 {
1182         hdlc_device *hdlc = dev_to_hdlc(frad);
1183         struct pvc_device *pvc = state(hdlc)->first_pvc;
1184         state(hdlc)->first_pvc = NULL; /* All PVCs destroyed */
1185         state(hdlc)->dce_pvc_count = 0;
1186         state(hdlc)->dce_changed = 1;
1187
1188         while (pvc) {
1189                 struct pvc_device *next = pvc->next;
1190                 /* destructors will free_netdev() main and ether */
1191                 if (pvc->main)
1192                         unregister_netdevice(pvc->main);
1193
1194                 if (pvc->ether)
1195                         unregister_netdevice(pvc->ether);
1196
1197                 kfree(pvc);
1198                 pvc = next;
1199         }
1200 }
1201
1202
1203 static struct hdlc_proto proto = {
1204         .close          = fr_close,
1205         .start          = fr_start,
1206         .stop           = fr_stop,
1207         .detach         = fr_destroy,
1208         .ioctl          = fr_ioctl,
1209         .netif_rx       = fr_rx,
1210         .module         = THIS_MODULE,
1211 };
1212
1213
1214 static int fr_ioctl(struct net_device *dev, struct ifreq *ifr)
1215 {
1216         fr_proto __user *fr_s = ifr->ifr_settings.ifs_ifsu.fr;
1217         const size_t size = sizeof(fr_proto);
1218         fr_proto new_settings;
1219         hdlc_device *hdlc = dev_to_hdlc(dev);
1220         fr_proto_pvc pvc;
1221         int result;
1222
1223         switch (ifr->ifr_settings.type) {
1224         case IF_GET_PROTO:
1225                 if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1226                         return -EINVAL;
1227                 ifr->ifr_settings.type = IF_PROTO_FR;
1228                 if (ifr->ifr_settings.size < size) {
1229                         ifr->ifr_settings.size = size; /* data size wanted */
1230                         return -ENOBUFS;
1231                 }
1232                 if (copy_to_user(fr_s, &state(hdlc)->settings, size))
1233                         return -EFAULT;
1234                 return 0;
1235
1236         case IF_PROTO_FR:
1237                 if (!capable(CAP_NET_ADMIN))
1238                         return -EPERM;
1239
1240                 if (dev->flags & IFF_UP)
1241                         return -EBUSY;
1242
1243                 if (copy_from_user(&new_settings, fr_s, size))
1244                         return -EFAULT;
1245
1246                 if (new_settings.lmi == LMI_DEFAULT)
1247                         new_settings.lmi = LMI_ANSI;
1248
1249                 if ((new_settings.lmi != LMI_NONE &&
1250                      new_settings.lmi != LMI_ANSI &&
1251                      new_settings.lmi != LMI_CCITT &&
1252                      new_settings.lmi != LMI_CISCO) ||
1253                     new_settings.t391 < 1 ||
1254                     new_settings.t392 < 2 ||
1255                     new_settings.n391 < 1 ||
1256                     new_settings.n392 < 1 ||
1257                     new_settings.n393 < new_settings.n392 ||
1258                     new_settings.n393 > 32 ||
1259                     (new_settings.dce != 0 &&
1260                      new_settings.dce != 1))
1261                         return -EINVAL;
1262
1263                 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
1264                 if (result)
1265                         return result;
1266
1267                 if (dev_to_hdlc(dev)->proto != &proto) { /* Different proto */
1268                         result = attach_hdlc_protocol(dev, &proto,
1269                                                       sizeof(struct frad_state));
1270                         if (result)
1271                                 return result;
1272                         state(hdlc)->first_pvc = NULL;
1273                         state(hdlc)->dce_pvc_count = 0;
1274                 }
1275                 memcpy(&state(hdlc)->settings, &new_settings, size);
1276                 dev->type = ARPHRD_FRAD;
1277                 call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
1278                 return 0;
1279
1280         case IF_PROTO_FR_ADD_PVC:
1281         case IF_PROTO_FR_DEL_PVC:
1282         case IF_PROTO_FR_ADD_ETH_PVC:
1283         case IF_PROTO_FR_DEL_ETH_PVC:
1284                 if (dev_to_hdlc(dev)->proto != &proto) /* Different proto */
1285                         return -EINVAL;
1286
1287                 if (!capable(CAP_NET_ADMIN))
1288                         return -EPERM;
1289
1290                 if (copy_from_user(&pvc, ifr->ifr_settings.ifs_ifsu.fr_pvc,
1291                                    sizeof(fr_proto_pvc)))
1292                         return -EFAULT;
1293
1294                 if (pvc.dlci <= 0 || pvc.dlci >= 1024)
1295                         return -EINVAL; /* Only 10 bits, DLCI 0 reserved */
1296
1297                 if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC ||
1298                     ifr->ifr_settings.type == IF_PROTO_FR_DEL_ETH_PVC)
1299                         result = ARPHRD_ETHER; /* bridged Ethernet device */
1300                 else
1301                         result = ARPHRD_DLCI;
1302
1303                 if (ifr->ifr_settings.type == IF_PROTO_FR_ADD_PVC ||
1304                     ifr->ifr_settings.type == IF_PROTO_FR_ADD_ETH_PVC)
1305                         return fr_add_pvc(dev, pvc.dlci, result);
1306                 else
1307                         return fr_del_pvc(hdlc, pvc.dlci, result);
1308         }
1309
1310         return -EINVAL;
1311 }
1312
1313
1314 static int __init mod_init(void)
1315 {
1316         register_hdlc_protocol(&proto);
1317         return 0;
1318 }
1319
1320
1321 static void __exit mod_exit(void)
1322 {
1323         unregister_hdlc_protocol(&proto);
1324 }
1325
1326
1327 module_init(mod_init);
1328 module_exit(mod_exit);
1329
1330 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
1331 MODULE_DESCRIPTION("Frame-Relay protocol support for generic HDLC");
1332 MODULE_LICENSE("GPL v2");