1 /*
2 * DECnet An implementation of the DECnet protocol suite for the LINUX
3 * operating system. DECnet is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * DECnet Neighbour Functions (Adjacency Database and
7 * On-Ethernet Cache)
8 *
9 * Author: Steve Whitehouse <SteveW@ACM.org>
10 *
11 *
12 * Changes:
13 * Steve Whitehouse : Fixed router listing routine
14 * Steve Whitehouse : Added error_report functions
15 * Steve Whitehouse : Added default router detection
16 * Steve Whitehouse : Hop counts in outgoing messages
17 * Steve Whitehouse : Fixed src/dst in outgoing messages so
18 * forwarding now stands a good chance of
19 * working.
20 * Steve Whitehouse : Fixed neighbour states (for now anyway).
21 * Steve Whitehouse : Made error_report functions dummies. This
22 * is not the right place to return skbs.
23 * Steve Whitehouse : Convert to seq_file
24 *
25 */
26
27 #include <linux/config.h>
28 #include <linux/net.h>
29 #include <linux/module.h>
30 #include <linux/socket.h>
31 #include <linux/if_arp.h>
32 #include <linux/if_ether.h>
33 #include <linux/init.h>
34 #include <linux/proc_fs.h>
35 #include <linux/string.h>
36 #include <linux/netfilter_decnet.h>
37 #include <linux/spinlock.h>
38 #include <linux/seq_file.h>
39 #include <linux/rcupdate.h>
40 #include <linux/jhash.h>
41 #include <asm/atomic.h>
42 #include <net/neighbour.h>
43 #include <net/dst.h>
44 #include <net/flow.h>
45 #include <net/dn.h>
46 #include <net/dn_dev.h>
47 #include <net/dn_neigh.h>
48 #include <net/dn_route.h>
49
50 static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev);
51 static int dn_neigh_construct(struct neighbour *);
52 static void dn_long_error_report(struct neighbour *, struct sk_buff *);
53 static void dn_short_error_report(struct neighbour *, struct sk_buff *);
54 static int dn_long_output(struct sk_buff *);
55 static int dn_short_output(struct sk_buff *);
56 static int dn_phase3_output(struct sk_buff *);
57
58
59 /*
60 * For talking to broadcast devices: Ethernet & PPP
61 */
62 static struct neigh_ops dn_long_ops = {
63 .family = AF_DECnet,
64 .error_report = dn_long_error_report,
65 .output = dn_long_output,
66 .connected_output = dn_long_output,
67 .hh_output = dev_queue_xmit,
68 .queue_xmit = dev_queue_xmit,
69 };
70
71 /*
72 * For talking to pointopoint and multidrop devices: DDCMP and X.25
73 */
74 static struct neigh_ops dn_short_ops = {
75 .family = AF_DECnet,
76 .error_report = dn_short_error_report,
77 .output = dn_short_output,
78 .connected_output = dn_short_output,
79 .hh_output = dev_queue_xmit,
80 .queue_xmit = dev_queue_xmit,
81 };
82
83 /*
84 * For talking to DECnet phase III nodes
85 */
86 static struct neigh_ops dn_phase3_ops = {
87 .family = AF_DECnet,
88 .error_report = dn_short_error_report, /* Can use short version here */
89 .output = dn_phase3_output,
90 .connected_output = dn_phase3_output,
91 .hh_output = dev_queue_xmit,
92 .queue_xmit = dev_queue_xmit
93 };
94
95 struct neigh_table dn_neigh_table = {
96 .family = PF_DECnet,
97 .entry_size = sizeof(struct dn_neigh),
98 .key_len = sizeof(dn_address),
99 .hash = dn_neigh_hash,
100 .constructor = dn_neigh_construct,
101 .id = "dn_neigh_cache",
102 .parms ={
103 .tbl = &dn_neigh_table,
104 .entries = 0,
105 .base_reachable_time = 30 * HZ,
106 .retrans_time = 1 * HZ,
107 .gc_staletime = 60 * HZ,
108 .reachable_time = 30 * HZ,
109 .delay_probe_time = 5 * HZ,
110 .queue_len = 3,
111 .ucast_probes = 0,
112 .app_probes = 0,
113 .mcast_probes = 0,
114 .anycast_delay = 0,
115 .proxy_delay = 0,
116 .proxy_qlen = 0,
117 .locktime = 1 * HZ,
118 },
119 .gc_interval = 30 * HZ,
120 .gc_thresh1 = 128,
121 .gc_thresh2 = 512,
122 .gc_thresh3 = 1024,
123 };
124
125 static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev)
126 {
127 return jhash_2words(*(dn_address *)pkey, 0, dn_neigh_table.hash_rnd);
128 }
129
130 static int dn_neigh_construct(struct neighbour *neigh)
131 {
132 struct net_device *dev = neigh->dev;
133 struct dn_neigh *dn = (struct dn_neigh *)neigh;
134 struct dn_dev *dn_db;
135 struct neigh_parms *parms;
136
137 rcu_read_lock();
138 dn_db = rcu_dereference(dev->dn_ptr);
139 if (dn_db == NULL) {
140 rcu_read_unlock();
141 return -EINVAL;
142 }
143
144 parms = dn_db->neigh_parms;
145 if (!parms) {
146 rcu_read_unlock();
147 return -EINVAL;
148 }
149
150 __neigh_parms_put(neigh->parms);
151 neigh->parms = neigh_parms_clone(parms);
152 rcu_read_unlock();
153
154 if (dn_db->use_long)
155 neigh->ops = &dn_long_ops;
156 else
157 neigh->ops = &dn_short_ops;
158
159 if (dn->flags & DN_NDFLAG_P3)
160 neigh->ops = &dn_phase3_ops;
161
162 neigh->nud_state = NUD_NOARP;
163 neigh->output = neigh->ops->connected_output;
164
165 if ((dev->type == ARPHRD_IPGRE) || (dev->flags & IFF_POINTOPOINT))
166 memcpy(neigh->ha, dev->broadcast, dev->addr_len);
167 else if ((dev->type == ARPHRD_ETHER) || (dev->type == ARPHRD_LOOPBACK))
168 dn_dn2eth(neigh->ha, dn->addr);
169 else {
170 if (net_ratelimit())
171 printk(KERN_DEBUG "Trying to create neigh for hw %d\n", dev->type);
172 return -EINVAL;
173 }
174
175 /*
176 * Make an estimate of the remote block size by assuming that its
177 * two less then the device mtu, which it true for ethernet (and
178 * other things which support long format headers) since there is
179 * an extra length field (of 16 bits) which isn't part of the
180 * ethernet headers and which the DECnet specs won't admit is part
181 * of the DECnet routing headers either.
182 *
183 * If we over estimate here its no big deal, the NSP negotiations
184 * will prevent us from sending packets which are too large for the
185 * remote node to handle. In any case this figure is normally updated
186 * by a hello message in most cases.
187 */
188 dn->blksize = dev->mtu - 2;
189
190 return 0;
191 }
192
193 static void dn_long_error_report(struct neighbour *neigh, struct sk_buff *skb)
194 {
195 printk(KERN_DEBUG "dn_long_error_report: called\n");
196 kfree_skb(skb);
197 }
198
199
200 static void dn_short_error_report(struct neighbour *neigh, struct sk_buff *skb)
201 {
202 printk(KERN_DEBUG "dn_short_error_report: called\n");
203 kfree_skb(skb);
204 }
205
206 static int dn_neigh_output_packet(struct sk_buff *skb)
207 {
208 struct dst_entry *dst = skb->dst;
209 struct dn_route *rt = (struct dn_route *)dst;
210 struct neighbour *neigh = dst->neighbour;
211 struct net_device *dev = neigh->dev;
212 char mac_addr[ETH_ALEN];
213
214 dn_dn2eth(mac_addr, rt->rt_local_src);
215 if (!dev->hard_header || dev->hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, mac_addr, skb->len) >= 0)
216 return neigh->ops->queue_xmit(skb);
217
218 if (net_ratelimit())
219 printk(KERN_DEBUG "dn_neigh_output_packet: oops, can't send packet\n");
220
221 kfree_skb(skb);
222 return -EINVAL;
223 }
224
225 static int dn_long_output(struct sk_buff *skb)
226 {
227 struct dst_entry *dst = skb->dst;
228 struct neighbour *neigh = dst->neighbour;
229 struct net_device *dev = neigh->dev;
230 int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
231 unsigned char *data;
232 struct dn_long_packet *lp;
233 struct dn_skb_cb *cb = DN_SKB_CB(skb);
234
235
236 if (skb_headroom(skb) < headroom) {
237 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
238 if (skb2 == NULL) {
239 if (net_ratelimit())
240 printk(KERN_CRIT "dn_long_output: no memory\n");
241 kfree_skb(skb);
242 return -ENOBUFS;
243 }
244 kfree_skb(skb);
245 skb = skb2;
246 if (net_ratelimit())
247 printk(KERN_INFO "dn_long_output: Increasing headroom\n");
248 }
249
250 data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
251 lp = (struct dn_long_packet *)(data+3);
252
253 *((unsigned short *)data) = dn_htons(skb->len - 2);
254 *(data + 2) = 1 | DN_RT_F_PF; /* Padding */
255
256 lp->msgflg = DN_RT_PKT_LONG|(cb->rt_flags&(DN_RT_F_IE|DN_RT_F_RQR|DN_RT_F_RTS));
257 lp->d_area = lp->d_subarea = 0;
258 dn_dn2eth(lp->d_id, dn_ntohs(cb->dst));
259 lp->s_area = lp->s_subarea = 0;
260 dn_dn2eth(lp->s_id, dn_ntohs(cb->src));
261 lp->nl2 = 0;
262 lp->visit_ct = cb->hops & 0x3f;
263 lp->s_class = 0;
264 lp->pt = 0;
265
266 skb->nh.raw = skb->data;
267
268 return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
269 }
270
271 static int dn_short_output(struct sk_buff *skb)
272 {
273 struct dst_entry *dst = skb->dst;
274 struct neighbour *neigh = dst->neighbour;
275 struct net_device *dev = neigh->dev;
276 int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
277 struct dn_short_packet *sp;
278 unsigned char *data;
279 struct dn_skb_cb *cb = DN_SKB_CB(skb);
280
281
282 if (skb_headroom(skb) < headroom) {
283 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
284 if (skb2 == NULL) {
285 if (net_ratelimit())
286 printk(KERN_CRIT "dn_short_output: no memory\n");
287 kfree_skb(skb);
288 return -ENOBUFS;
289 }
290 kfree_skb(skb);
291 skb = skb2;
292 if (net_ratelimit())
293 printk(KERN_INFO "dn_short_output: Increasing headroom\n");
294 }
295
296 data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
297 *((unsigned short *)data) = dn_htons(skb->len - 2);
298 sp = (struct dn_short_packet *)(data+2);
299
300 sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
301 sp->dstnode = cb->dst;
302 sp->srcnode = cb->src;
303 sp->forward = cb->hops & 0x3f;
304
305 skb->nh.raw = skb->data;
306
307 return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
308 }
309
310 /*
311 * Phase 3 output is the same is short output, execpt that
312 * it clears the area bits before transmission.
313 */
314 static int dn_phase3_output(struct sk_buff *skb)
315 {
316 struct dst_entry *dst = skb->dst;
317 struct neighbour *neigh = dst->neighbour;
318 struct net_device *dev = neigh->dev;
319 int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
320 struct dn_short_packet *sp;
321 unsigned char *data;
322 struct dn_skb_cb *cb = DN_SKB_CB(skb);
323
324 if (skb_headroom(skb) < headroom) {
325 struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
326 if (skb2 == NULL) {
327 if (net_ratelimit())
328 printk(KERN_CRIT "dn_phase3_output: no memory\n");
329 kfree_skb(skb);
330 return -ENOBUFS;
331 }
332 kfree_skb(skb);
333 skb = skb2;
334 if (net_ratelimit())
335 printk(KERN_INFO "dn_phase3_output: Increasing headroom\n");
336 }
337
338 data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
339 *((unsigned short *)data) = dn_htons(skb->len - 2);
340 sp = (struct dn_short_packet *)(data + 2);
341
342 sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
343 sp->dstnode = cb->dst & dn_htons(0x03ff);
344 sp->srcnode = cb->src & dn_htons(0x03ff);
345 sp->forward = cb->hops & 0x3f;
346
347 skb->nh.raw = skb->data;
348
349 return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
350 }
351
352 /*
353 * Unfortunately, the neighbour code uses the device in its hash
354 * function, so we don't get any advantage from it. This function
355 * basically does a neigh_lookup(), but without comparing the device
356 * field. This is required for the On-Ethernet cache
357 */
358
359 /*
360 * Pointopoint link receives a hello message
361 */
362 void dn_neigh_pointopoint_hello(struct sk_buff *skb)
363 {
364 kfree_skb(skb);
365 }
366
367 /*
368 * Ethernet router hello message received
369 */
370 int dn_neigh_router_hello(struct sk_buff *skb)
371 {
372 struct rtnode_hello_message *msg = (struct rtnode_hello_message *)skb->data;
373
374 struct neighbour *neigh;
375 struct dn_neigh *dn;
376 struct dn_dev *dn_db;
377 dn_address src;
378
379 src = dn_htons(dn_eth2dn(msg->id));
380
381 neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
382
383 dn = (struct dn_neigh *)neigh;
384
385 if (neigh) {
386 write_lock(&neigh->lock);
387
388 neigh->used = jiffies;
389 dn_db = (struct dn_dev *)neigh->dev->dn_ptr;
390
391 if (!(neigh->nud_state & NUD_PERMANENT)) {
392 neigh->updated = jiffies;
393
394 if (neigh->dev->type == ARPHRD_ETHER)
395 memcpy(neigh->ha, ð_hdr(skb)->h_source, ETH_ALEN);
396
397 dn->blksize = dn_ntohs(msg->blksize);
398 dn->priority = msg->priority;
399
400 dn->flags &= ~DN_NDFLAG_P3;
401
402 switch(msg->iinfo & DN_RT_INFO_TYPE) {
403 case DN_RT_INFO_L1RT:
404 dn->flags &=~DN_NDFLAG_R2;
405 dn->flags |= DN_NDFLAG_R1;
406 break;
407 case DN_RT_INFO_L2RT:
408 dn->flags |= DN_NDFLAG_R2;
409 }
410 }
411
412 if (!dn_db->router) {
413 dn_db->router = neigh_clone(neigh);
414 } else {
415 if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
416 neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
417 }
418 write_unlock(&neigh->lock);
419 neigh_release(neigh);
420 }
421
422 kfree_skb(skb);
423 return 0;
424 }
425
426 /*
427 * Endnode hello message received
428 */
429 int dn_neigh_endnode_hello(struct sk_buff *skb)
430 {
431 struct endnode_hello_message *msg = (struct endnode_hello_message *)skb->data;
432 struct neighbour *neigh;
433 struct dn_neigh *dn;
434 dn_address src;
435
436 src = dn_htons(dn_eth2dn(msg->id));
437
438 neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
439
440 dn = (struct dn_neigh *)neigh;
441
442 if (neigh) {
443 write_lock(&neigh->lock);
444
445 neigh->used = jiffies;
446
447 if (!(neigh->nud_state & NUD_PERMANENT)) {
448 neigh->updated = jiffies;
449
450 if (neigh->dev->type == ARPHRD_ETHER)
451 memcpy(neigh->ha, ð_hdr(skb)->h_source, ETH_ALEN);
452 dn->flags &= ~(DN_NDFLAG_R1 | DN_NDFLAG_R2);
453 dn->blksize = dn_ntohs(msg->blksize);
454 dn->priority = 0;
455 }
456
457 write_unlock(&neigh->lock);
458 neigh_release(neigh);
459 }
460
461 kfree_skb(skb);
462 return 0;
463 }
464
465 static char *dn_find_slot(char *base, int max, int priority)
466 {
467 int i;
468 unsigned char *min = NULL;
469
470 base += 6; /* skip first id */
471
472 for(i = 0; i < max; i++) {
473 if (!min || (*base < *min))
474 min = base;
475 base += 7; /* find next priority */
476 }
477
478 if (!min)
479 return NULL;
480
481 return (*min < priority) ? (min - 6) : NULL;
482 }
483
484 struct elist_cb_state {
485 struct net_device *dev;
486 unsigned char *ptr;
487 unsigned char *rs;
488 int t, n;
489 };
490
491 static void neigh_elist_cb(struct neighbour *neigh, void *_info)
492 {
493 struct elist_cb_state *s = _info;
494 struct dn_dev *dn_db;
495 struct dn_neigh *dn;
496
497 if (neigh->dev != s->dev)
498 return;
499
500 dn = (struct dn_neigh *) neigh;
501 if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
502 return;
503
504 dn_db = (struct dn_dev *) s->dev->dn_ptr;
505 if (dn_db->parms.forwarding == 1 && (dn->flags & DN_NDFLAG_R2))
506 return;
507
508 if (s->t == s->n)
509 s->rs = dn_find_slot(s->ptr, s->n, dn->priority);
510 else
511 s->t++;
512 if (s->rs == NULL)
513 return;
514
515 dn_dn2eth(s->rs, dn->addr);
516 s->rs += 6;
517 *(s->rs) = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
518 *(s->rs) |= dn->priority;
519 s->rs++;
520 }
521
522 int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
523 {
524 struct elist_cb_state state;
525
526 state.dev = dev;
527 state.t = 0;
528 state.n = n;
529 state.ptr = ptr;
530 state.rs = ptr;
531
532 neigh_for_each(&dn_neigh_table, neigh_elist_cb, &state);
533
534 return state.t;
535 }
536
537
538 #ifdef CONFIG_PROC_FS
539
540 static inline void dn_neigh_format_entry(struct seq_file *seq,
541 struct neighbour *n)
542 {
543 struct dn_neigh *dn = (struct dn_neigh *) n;
544 char buf[DN_ASCBUF_LEN];
545
546 read_lock(&n->lock);
547 seq_printf(seq, "%-7s %s%s%s %02x %02d %07ld %-8s\n",
548 dn_addr2asc(dn_ntohs(dn->addr), buf),
549 (dn->flags&DN_NDFLAG_R1) ? "1" : "-",
550 (dn->flags&DN_NDFLAG_R2) ? "2" : "-",
551 (dn->flags&DN_NDFLAG_P3) ? "3" : "-",
552 dn->n.nud_state,
553 atomic_read(&dn->n.refcnt),
554 dn->blksize,
555 (dn->n.dev) ? dn->n.dev->name : "?");
556 read_unlock(&n->lock);
557 }
558
559 static int dn_neigh_seq_show(struct seq_file *seq, void *v)
560 {
561 if (v == SEQ_START_TOKEN) {
562 seq_puts(seq, "Addr Flags State Use Blksize Dev\n");
563 } else {
564 dn_neigh_format_entry(seq, v);
565 }
566
567 return 0;
568 }
569
570 static void *dn_neigh_seq_start(struct seq_file *seq, loff_t *pos)
571 {
572 return neigh_seq_start(seq, pos, &dn_neigh_table,
573 NEIGH_SEQ_NEIGH_ONLY);
574 }
575
576 static struct seq_operations dn_neigh_seq_ops = {
577 .start = dn_neigh_seq_start,
578 .next = neigh_seq_next,
579 .stop = neigh_seq_stop,
580 .show = dn_neigh_seq_show,
581 };
582
583 static int dn_neigh_seq_open(struct inode *inode, struct file *file)
584 {
585 struct seq_file *seq;
586 int rc = -ENOMEM;
587 struct neigh_seq_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
588
589 if (!s)
590 goto out;
591
592 memset(s, 0, sizeof(*s));
593 rc = seq_open(file, &dn_neigh_seq_ops);
594 if (rc)
595 goto out_kfree;
596
597 seq = file->private_data;
598 seq->private = s;
599 memset(s, 0, sizeof(*s));
600 out:
601 return rc;
602 out_kfree:
603 kfree(s);
604 goto out;
605 }
606
607 static struct file_operations dn_neigh_seq_fops = {
608 .owner = THIS_MODULE,
609 .open = dn_neigh_seq_open,
610 .read = seq_read,
611 .llseek = seq_lseek,
612 .release = seq_release_private,
613 };
614
615 #endif
616
617 void __init dn_neigh_init(void)
618 {
619 neigh_table_init(&dn_neigh_table);
620 proc_net_fops_create("decnet_neigh", S_IRUGO, &dn_neigh_seq_fops);
621 }
622
623 void __exit dn_neigh_cleanup(void)
624 {
625 proc_net_remove("decnet_neigh");
626 neigh_table_clear(&dn_neigh_table);
627 }
628
|
This page was automatically generated by the
LXR engine.
|