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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 Routing Forwarding Information Base (Routing Tables)
7 *
8 * Author: Steve Whitehouse <SteveW@ACM.org>
9 * Mostly copied from the IPv4 routing code
10 *
11 *
12 * Changes:
13 *
14 */
15#include <linux/string.h>
16#include <linux/net.h>
17#include <linux/socket.h>
18#include <linux/slab.h>
19#include <linux/sockios.h>
20#include <linux/init.h>
21#include <linux/skbuff.h>
22#include <linux/rtnetlink.h>
23#include <linux/proc_fs.h>
24#include <linux/netdevice.h>
25#include <linux/timer.h>
26#include <linux/spinlock.h>
27#include <linux/atomic.h>
28#include <asm/uaccess.h>
29#include <linux/route.h> /* RTF_xxx */
30#include <net/neighbour.h>
31#include <net/netlink.h>
32#include <net/tcp.h>
33#include <net/dst.h>
34#include <net/flow.h>
35#include <net/fib_rules.h>
36#include <net/dn.h>
37#include <net/dn_route.h>
38#include <net/dn_fib.h>
39#include <net/dn_neigh.h>
40#include <net/dn_dev.h>
41
42struct dn_zone
43{
44 struct dn_zone *dz_next;
45 struct dn_fib_node **dz_hash;
46 int dz_nent;
47 int dz_divisor;
48 u32 dz_hashmask;
49#define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
50 int dz_order;
51 __le16 dz_mask;
52#define DZ_MASK(dz) ((dz)->dz_mask)
53};
54
55struct dn_hash
56{
57 struct dn_zone *dh_zones[17];
58 struct dn_zone *dh_zone_list;
59};
60
61#define dz_key_0(key) ((key).datum = 0)
62
63#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
64 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
65
66#define endfor_nexthops(fi) }
67
68#define DN_MAX_DIVISOR 1024
69#define DN_S_ZOMBIE 1
70#define DN_S_ACCESSED 2
71
72#define DN_FIB_SCAN(f, fp) \
73for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
74
75#define DN_FIB_SCAN_KEY(f, fp, key) \
76for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
77
78#define RT_TABLE_MIN 1
79#define DN_FIB_TABLE_HASHSZ 256
80static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
81static DEFINE_RWLOCK(dn_fib_tables_lock);
82
83static struct kmem_cache *dn_hash_kmem __read_mostly;
84static int dn_fib_hash_zombies;
85
86static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
87{
88 u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order);
89 h ^= (h >> 10);
90 h ^= (h >> 6);
91 h &= DZ_HASHMASK(dz);
92 return *(dn_fib_idx_t *)&h;
93}
94
95static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz)
96{
97 dn_fib_key_t k;
98 k.datum = dst & DZ_MASK(dz);
99 return k;
100}
101
102static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
103{
104 return &dz->dz_hash[dn_hash(key, dz).datum];
105}
106
107static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
108{
109 return dz->dz_hash[dn_hash(key, dz).datum];
110}
111
112static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
113{
114 return a.datum == b.datum;
115}
116
117static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
118{
119 return a.datum <= b.datum;
120}
121
122static inline void dn_rebuild_zone(struct dn_zone *dz,
123 struct dn_fib_node **old_ht,
124 int old_divisor)
125{
126 struct dn_fib_node *f, **fp, *next;
127 int i;
128
129 for(i = 0; i < old_divisor; i++) {
130 for(f = old_ht[i]; f; f = next) {
131 next = f->fn_next;
132 for(fp = dn_chain_p(f->fn_key, dz);
133 *fp && dn_key_leq((*fp)->fn_key, f->fn_key);
134 fp = &(*fp)->fn_next)
135 /* NOTHING */;
136 f->fn_next = *fp;
137 *fp = f;
138 }
139 }
140}
141
142static void dn_rehash_zone(struct dn_zone *dz)
143{
144 struct dn_fib_node **ht, **old_ht;
145 int old_divisor, new_divisor;
146 u32 new_hashmask;
147
148 old_divisor = dz->dz_divisor;
149
150 switch (old_divisor) {
151 case 16:
152 new_divisor = 256;
153 new_hashmask = 0xFF;
154 break;
155 default:
156 printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n",
157 old_divisor);
158 case 256:
159 new_divisor = 1024;
160 new_hashmask = 0x3FF;
161 break;
162 }
163
164 ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL);
165 if (ht == NULL)
166 return;
167
168 write_lock_bh(&dn_fib_tables_lock);
169 old_ht = dz->dz_hash;
170 dz->dz_hash = ht;
171 dz->dz_hashmask = new_hashmask;
172 dz->dz_divisor = new_divisor;
173 dn_rebuild_zone(dz, old_ht, old_divisor);
174 write_unlock_bh(&dn_fib_tables_lock);
175 kfree(old_ht);
176}
177
178static void dn_free_node(struct dn_fib_node *f)
179{
180 dn_fib_release_info(DN_FIB_INFO(f));
181 kmem_cache_free(dn_hash_kmem, f);
182}
183
184
185static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
186{
187 int i;
188 struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL);
189 if (!dz)
190 return NULL;
191
192 if (z) {
193 dz->dz_divisor = 16;
194 dz->dz_hashmask = 0x0F;
195 } else {
196 dz->dz_divisor = 1;
197 dz->dz_hashmask = 0;
198 }
199
200 dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL);
201 if (!dz->dz_hash) {
202 kfree(dz);
203 return NULL;
204 }
205
206 dz->dz_order = z;
207 dz->dz_mask = dnet_make_mask(z);
208
209 for(i = z + 1; i <= 16; i++)
210 if (table->dh_zones[i])
211 break;
212
213 write_lock_bh(&dn_fib_tables_lock);
214 if (i>16) {
215 dz->dz_next = table->dh_zone_list;
216 table->dh_zone_list = dz;
217 } else {
218 dz->dz_next = table->dh_zones[i]->dz_next;
219 table->dh_zones[i]->dz_next = dz;
220 }
221 table->dh_zones[z] = dz;
222 write_unlock_bh(&dn_fib_tables_lock);
223 return dz;
224}
225
226
227static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
228{
229 struct rtnexthop *nhp;
230 int nhlen;
231
232 if (attrs[RTA_PRIORITY] &&
233 nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
234 return 1;
235
236 if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
237 if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
238 (!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
239 return 0;
240 return 1;
241 }
242
243 if (!attrs[RTA_MULTIPATH])
244 return 0;
245
246 nhp = nla_data(attrs[RTA_MULTIPATH]);
247 nhlen = nla_len(attrs[RTA_MULTIPATH]);
248
249 for_nexthops(fi) {
250 int attrlen = nhlen - sizeof(struct rtnexthop);
251 __le16 gw;
252
253 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
254 return -EINVAL;
255 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
256 return 1;
257 if (attrlen) {
258 struct nlattr *gw_attr;
259
260 gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
261 gw = gw_attr ? nla_get_le16(gw_attr) : 0;
262
263 if (gw && gw != nh->nh_gw)
264 return 1;
265 }
266 nhp = RTNH_NEXT(nhp);
267 } endfor_nexthops(fi);
268
269 return 0;
270}
271
272static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
273{
274 size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
275 + nla_total_size(4) /* RTA_TABLE */
276 + nla_total_size(2) /* RTA_DST */
277 + nla_total_size(4) /* RTA_PRIORITY */
278 + nla_total_size(TCP_CA_NAME_MAX); /* RTAX_CC_ALGO */
279
280 /* space for nested metrics */
281 payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
282
283 if (fi->fib_nhs) {
284 /* Also handles the special case fib_nhs == 1 */
285
286 /* each nexthop is packed in an attribute */
287 size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
288
289 /* may contain a gateway attribute */
290 nhsize += nla_total_size(4);
291
292 /* all nexthops are packed in a nested attribute */
293 payload += nla_total_size(fi->fib_nhs * nhsize);
294 }
295
296 return payload;
297}
298
299static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
300 u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
301 struct dn_fib_info *fi, unsigned int flags)
302{
303 struct rtmsg *rtm;
304 struct nlmsghdr *nlh;
305
306 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
307 if (!nlh)
308 return -EMSGSIZE;
309
310 rtm = nlmsg_data(nlh);
311 rtm->rtm_family = AF_DECnet;
312 rtm->rtm_dst_len = dst_len;
313 rtm->rtm_src_len = 0;
314 rtm->rtm_tos = 0;
315 rtm->rtm_table = tb_id;
316 rtm->rtm_flags = fi->fib_flags;
317 rtm->rtm_scope = scope;
318 rtm->rtm_type = type;
319 rtm->rtm_protocol = fi->fib_protocol;
320
321 if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0)
322 goto errout;
323
324 if (rtm->rtm_dst_len &&
325 nla_put(skb, RTA_DST, 2, dst) < 0)
326 goto errout;
327
328 if (fi->fib_priority &&
329 nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0)
330 goto errout;
331
332 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
333 goto errout;
334
335 if (fi->fib_nhs == 1) {
336 if (fi->fib_nh->nh_gw &&
337 nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0)
338 goto errout;
339
340 if (fi->fib_nh->nh_oif &&
341 nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif) < 0)
342 goto errout;
343 }
344
345 if (fi->fib_nhs > 1) {
346 struct rtnexthop *nhp;
347 struct nlattr *mp_head;
348
349 if (!(mp_head = nla_nest_start(skb, RTA_MULTIPATH)))
350 goto errout;
351
352 for_nexthops(fi) {
353 if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp))))
354 goto errout;
355
356 nhp->rtnh_flags = nh->nh_flags & 0xFF;
357 nhp->rtnh_hops = nh->nh_weight - 1;
358 nhp->rtnh_ifindex = nh->nh_oif;
359
360 if (nh->nh_gw &&
361 nla_put_le16(skb, RTA_GATEWAY, nh->nh_gw) < 0)
362 goto errout;
363
364 nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
365 } endfor_nexthops(fi);
366
367 nla_nest_end(skb, mp_head);
368 }
369
370 nlmsg_end(skb, nlh);
371 return 0;
372
373errout:
374 nlmsg_cancel(skb, nlh);
375 return -EMSGSIZE;
376}
377
378
379static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id,
380 struct nlmsghdr *nlh, struct netlink_skb_parms *req)
381{
382 struct sk_buff *skb;
383 u32 portid = req ? req->portid : 0;
384 int err = -ENOBUFS;
385
386 skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL);
387 if (skb == NULL)
388 goto errout;
389
390 err = dn_fib_dump_info(skb, portid, nlh->nlmsg_seq, event, tb_id,
391 f->fn_type, f->fn_scope, &f->fn_key, z,
392 DN_FIB_INFO(f), 0);
393 if (err < 0) {
394 /* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */
395 WARN_ON(err == -EMSGSIZE);
396 kfree_skb(skb);
397 goto errout;
398 }
399 rtnl_notify(skb, &init_net, portid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL);
400 return;
401errout:
402 if (err < 0)
403 rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err);
404}
405
406static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
407 struct netlink_callback *cb,
408 struct dn_fib_table *tb,
409 struct dn_zone *dz,
410 struct dn_fib_node *f)
411{
412 int i, s_i;
413
414 s_i = cb->args[4];
415 for(i = 0; f; i++, f = f->fn_next) {
416 if (i < s_i)
417 continue;
418 if (f->fn_state & DN_S_ZOMBIE)
419 continue;
420 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
421 cb->nlh->nlmsg_seq,
422 RTM_NEWROUTE,
423 tb->n,
424 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
425 f->fn_scope, &f->fn_key, dz->dz_order,
426 f->fn_info, NLM_F_MULTI) < 0) {
427 cb->args[4] = i;
428 return -1;
429 }
430 }
431 cb->args[4] = i;
432 return skb->len;
433}
434
435static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
436 struct netlink_callback *cb,
437 struct dn_fib_table *tb,
438 struct dn_zone *dz)
439{
440 int h, s_h;
441
442 s_h = cb->args[3];
443 for(h = 0; h < dz->dz_divisor; h++) {
444 if (h < s_h)
445 continue;
446 if (h > s_h)
447 memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0]));
448 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
449 continue;
450 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
451 cb->args[3] = h;
452 return -1;
453 }
454 }
455 cb->args[3] = h;
456 return skb->len;
457}
458
459static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
460 struct netlink_callback *cb)
461{
462 int m, s_m;
463 struct dn_zone *dz;
464 struct dn_hash *table = (struct dn_hash *)tb->data;
465
466 s_m = cb->args[2];
467 read_lock(&dn_fib_tables_lock);
468 for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
469 if (m < s_m)
470 continue;
471 if (m > s_m)
472 memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
473
474 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
475 cb->args[2] = m;
476 read_unlock(&dn_fib_tables_lock);
477 return -1;
478 }
479 }
480 read_unlock(&dn_fib_tables_lock);
481 cb->args[2] = m;
482
483 return skb->len;
484}
485
486int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
487{
488 struct net *net = sock_net(skb->sk);
489 unsigned int h, s_h;
490 unsigned int e = 0, s_e;
491 struct dn_fib_table *tb;
492 int dumped = 0;
493
494 if (!net_eq(net, &init_net))
495 return 0;
496
497 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
498 ((struct rtmsg *)nlmsg_data(cb->nlh))->rtm_flags&RTM_F_CLONED)
499 return dn_cache_dump(skb, cb);
500
501 s_h = cb->args[0];
502 s_e = cb->args[1];
503
504 for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) {
505 e = 0;
506 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) {
507 if (e < s_e)
508 goto next;
509 if (dumped)
510 memset(&cb->args[2], 0, sizeof(cb->args) -
511 2 * sizeof(cb->args[0]));
512 if (tb->dump(tb, skb, cb) < 0)
513 goto out;
514 dumped = 1;
515next:
516 e++;
517 }
518 }
519out:
520 cb->args[1] = e;
521 cb->args[0] = h;
522
523 return skb->len;
524}
525
526static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
527 struct nlmsghdr *n, struct netlink_skb_parms *req)
528{
529 struct dn_hash *table = (struct dn_hash *)tb->data;
530 struct dn_fib_node *new_f, *f, **fp, **del_fp;
531 struct dn_zone *dz;
532 struct dn_fib_info *fi;
533 int z = r->rtm_dst_len;
534 int type = r->rtm_type;
535 dn_fib_key_t key;
536 int err;
537
538 if (z > 16)
539 return -EINVAL;
540
541 dz = table->dh_zones[z];
542 if (!dz && !(dz = dn_new_zone(table, z)))
543 return -ENOBUFS;
544
545 dz_key_0(key);
546 if (attrs[RTA_DST]) {
547 __le16 dst = nla_get_le16(attrs[RTA_DST]);
548 if (dst & ~DZ_MASK(dz))
549 return -EINVAL;
550 key = dz_key(dst, dz);
551 }
552
553 if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
554 return err;
555
556 if (dz->dz_nent > (dz->dz_divisor << 2) &&
557 dz->dz_divisor > DN_MAX_DIVISOR &&
558 (z==16 || (1<<z) > dz->dz_divisor))
559 dn_rehash_zone(dz);
560
561 fp = dn_chain_p(key, dz);
562
563 DN_FIB_SCAN(f, fp) {
564 if (dn_key_leq(key, f->fn_key))
565 break;
566 }
567
568 del_fp = NULL;
569
570 if (f && (f->fn_state & DN_S_ZOMBIE) &&
571 dn_key_eq(f->fn_key, key)) {
572 del_fp = fp;
573 fp = &f->fn_next;
574 f = *fp;
575 goto create;
576 }
577
578 DN_FIB_SCAN_KEY(f, fp, key) {
579 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
580 break;
581 }
582
583 if (f && dn_key_eq(f->fn_key, key) &&
584 fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
585 struct dn_fib_node **ins_fp;
586
587 err = -EEXIST;
588 if (n->nlmsg_flags & NLM_F_EXCL)
589 goto out;
590
591 if (n->nlmsg_flags & NLM_F_REPLACE) {
592 del_fp = fp;
593 fp = &f->fn_next;
594 f = *fp;
595 goto replace;
596 }
597
598 ins_fp = fp;
599 err = -EEXIST;
600
601 DN_FIB_SCAN_KEY(f, fp, key) {
602 if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
603 break;
604 if (f->fn_type == type &&
605 f->fn_scope == r->rtm_scope &&
606 DN_FIB_INFO(f) == fi)
607 goto out;
608 }
609
610 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
611 fp = ins_fp;
612 f = *fp;
613 }
614 }
615
616create:
617 err = -ENOENT;
618 if (!(n->nlmsg_flags & NLM_F_CREATE))
619 goto out;
620
621replace:
622 err = -ENOBUFS;
623 new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL);
624 if (new_f == NULL)
625 goto out;
626
627 new_f->fn_key = key;
628 new_f->fn_type = type;
629 new_f->fn_scope = r->rtm_scope;
630 DN_FIB_INFO(new_f) = fi;
631
632 new_f->fn_next = f;
633 write_lock_bh(&dn_fib_tables_lock);
634 *fp = new_f;
635 write_unlock_bh(&dn_fib_tables_lock);
636 dz->dz_nent++;
637
638 if (del_fp) {
639 f = *del_fp;
640 write_lock_bh(&dn_fib_tables_lock);
641 *del_fp = f->fn_next;
642 write_unlock_bh(&dn_fib_tables_lock);
643
644 if (!(f->fn_state & DN_S_ZOMBIE))
645 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
646 if (f->fn_state & DN_S_ACCESSED)
647 dn_rt_cache_flush(-1);
648 dn_free_node(f);
649 dz->dz_nent--;
650 } else {
651 dn_rt_cache_flush(-1);
652 }
653
654 dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
655
656 return 0;
657out:
658 dn_fib_release_info(fi);
659 return err;
660}
661
662
663static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
664 struct nlmsghdr *n, struct netlink_skb_parms *req)
665{
666 struct dn_hash *table = (struct dn_hash*)tb->data;
667 struct dn_fib_node **fp, **del_fp, *f;
668 int z = r->rtm_dst_len;
669 struct dn_zone *dz;
670 dn_fib_key_t key;
671 int matched;
672
673
674 if (z > 16)
675 return -EINVAL;
676
677 if ((dz = table->dh_zones[z]) == NULL)
678 return -ESRCH;
679
680 dz_key_0(key);
681 if (attrs[RTA_DST]) {
682 __le16 dst = nla_get_le16(attrs[RTA_DST]);
683 if (dst & ~DZ_MASK(dz))
684 return -EINVAL;
685 key = dz_key(dst, dz);
686 }
687
688 fp = dn_chain_p(key, dz);
689
690 DN_FIB_SCAN(f, fp) {
691 if (dn_key_eq(f->fn_key, key))
692 break;
693 if (dn_key_leq(key, f->fn_key))
694 return -ESRCH;
695 }
696
697 matched = 0;
698 del_fp = NULL;
699 DN_FIB_SCAN_KEY(f, fp, key) {
700 struct dn_fib_info *fi = DN_FIB_INFO(f);
701
702 if (f->fn_state & DN_S_ZOMBIE)
703 return -ESRCH;
704
705 matched++;
706
707 if (del_fp == NULL &&
708 (!r->rtm_type || f->fn_type == r->rtm_type) &&
709 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
710 (!r->rtm_protocol ||
711 fi->fib_protocol == r->rtm_protocol) &&
712 dn_fib_nh_match(r, n, attrs, fi) == 0)
713 del_fp = fp;
714 }
715
716 if (del_fp) {
717 f = *del_fp;
718 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
719
720 if (matched != 1) {
721 write_lock_bh(&dn_fib_tables_lock);
722 *del_fp = f->fn_next;
723 write_unlock_bh(&dn_fib_tables_lock);
724
725 if (f->fn_state & DN_S_ACCESSED)
726 dn_rt_cache_flush(-1);
727 dn_free_node(f);
728 dz->dz_nent--;
729 } else {
730 f->fn_state |= DN_S_ZOMBIE;
731 if (f->fn_state & DN_S_ACCESSED) {
732 f->fn_state &= ~DN_S_ACCESSED;
733 dn_rt_cache_flush(-1);
734 }
735 if (++dn_fib_hash_zombies > 128)
736 dn_fib_flush();
737 }
738
739 return 0;
740 }
741
742 return -ESRCH;
743}
744
745static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
746{
747 int found = 0;
748 struct dn_fib_node *f;
749
750 while((f = *fp) != NULL) {
751 struct dn_fib_info *fi = DN_FIB_INFO(f);
752
753 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
754 write_lock_bh(&dn_fib_tables_lock);
755 *fp = f->fn_next;
756 write_unlock_bh(&dn_fib_tables_lock);
757
758 dn_free_node(f);
759 found++;
760 continue;
761 }
762 fp = &f->fn_next;
763 }
764
765 return found;
766}
767
768static int dn_fib_table_flush(struct dn_fib_table *tb)
769{
770 struct dn_hash *table = (struct dn_hash *)tb->data;
771 struct dn_zone *dz;
772 int found = 0;
773
774 dn_fib_hash_zombies = 0;
775 for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
776 int i;
777 int tmp = 0;
778 for(i = dz->dz_divisor-1; i >= 0; i--)
779 tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
780 dz->dz_nent -= tmp;
781 found += tmp;
782 }
783
784 return found;
785}
786
787static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res)
788{
789 int err;
790 struct dn_zone *dz;
791 struct dn_hash *t = (struct dn_hash *)tb->data;
792
793 read_lock(&dn_fib_tables_lock);
794 for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
795 struct dn_fib_node *f;
796 dn_fib_key_t k = dz_key(flp->daddr, dz);
797
798 for(f = dz_chain(k, dz); f; f = f->fn_next) {
799 if (!dn_key_eq(k, f->fn_key)) {
800 if (dn_key_leq(k, f->fn_key))
801 break;
802 else
803 continue;
804 }
805
806 f->fn_state |= DN_S_ACCESSED;
807
808 if (f->fn_state&DN_S_ZOMBIE)
809 continue;
810
811 if (f->fn_scope < flp->flowidn_scope)
812 continue;
813
814 err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
815
816 if (err == 0) {
817 res->type = f->fn_type;
818 res->scope = f->fn_scope;
819 res->prefixlen = dz->dz_order;
820 goto out;
821 }
822 if (err < 0)
823 goto out;
824 }
825 }
826 err = 1;
827out:
828 read_unlock(&dn_fib_tables_lock);
829 return err;
830}
831
832
833struct dn_fib_table *dn_fib_get_table(u32 n, int create)
834{
835 struct dn_fib_table *t;
836 unsigned int h;
837
838 if (n < RT_TABLE_MIN)
839 return NULL;
840
841 if (n > RT_TABLE_MAX)
842 return NULL;
843
844 h = n & (DN_FIB_TABLE_HASHSZ - 1);
845 rcu_read_lock();
846 hlist_for_each_entry_rcu(t, &dn_fib_table_hash[h], hlist) {
847 if (t->n == n) {
848 rcu_read_unlock();
849 return t;
850 }
851 }
852 rcu_read_unlock();
853
854 if (!create)
855 return NULL;
856
857 if (in_interrupt()) {
858 net_dbg_ratelimited("DECnet: BUG! Attempt to create routing table from interrupt\n");
859 return NULL;
860 }
861
862 t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash),
863 GFP_KERNEL);
864 if (t == NULL)
865 return NULL;
866
867 t->n = n;
868 t->insert = dn_fib_table_insert;
869 t->delete = dn_fib_table_delete;
870 t->lookup = dn_fib_table_lookup;
871 t->flush = dn_fib_table_flush;
872 t->dump = dn_fib_table_dump;
873 hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]);
874
875 return t;
876}
877
878struct dn_fib_table *dn_fib_empty_table(void)
879{
880 u32 id;
881
882 for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
883 if (dn_fib_get_table(id, 0) == NULL)
884 return dn_fib_get_table(id, 1);
885 return NULL;
886}
887
888void dn_fib_flush(void)
889{
890 int flushed = 0;
891 struct dn_fib_table *tb;
892 unsigned int h;
893
894 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
895 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist)
896 flushed += tb->flush(tb);
897 }
898
899 if (flushed)
900 dn_rt_cache_flush(-1);
901}
902
903void __init dn_fib_table_init(void)
904{
905 dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
906 sizeof(struct dn_fib_info),
907 0, SLAB_HWCACHE_ALIGN,
908 NULL);
909}
910
911void __exit dn_fib_table_cleanup(void)
912{
913 struct dn_fib_table *t;
914 struct hlist_node *next;
915 unsigned int h;
916
917 write_lock(&dn_fib_tables_lock);
918 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
919 hlist_for_each_entry_safe(t, next, &dn_fib_table_hash[h],
920 hlist) {
921 hlist_del(&t->hlist);
922 kfree(t);
923 }
924 }
925 write_unlock(&dn_fib_tables_lock);
926}
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 Routing Forwarding Information Base (Routing Tables)
7 *
8 * Author: Steve Whitehouse <SteveW@ACM.org>
9 * Mostly copied from the IPv4 routing code
10 *
11 *
12 * Changes:
13 *
14 */
15#include <linux/string.h>
16#include <linux/net.h>
17#include <linux/socket.h>
18#include <linux/slab.h>
19#include <linux/sockios.h>
20#include <linux/init.h>
21#include <linux/skbuff.h>
22#include <linux/rtnetlink.h>
23#include <linux/proc_fs.h>
24#include <linux/netdevice.h>
25#include <linux/timer.h>
26#include <linux/spinlock.h>
27#include <linux/atomic.h>
28#include <asm/uaccess.h>
29#include <linux/route.h> /* RTF_xxx */
30#include <net/neighbour.h>
31#include <net/netlink.h>
32#include <net/dst.h>
33#include <net/flow.h>
34#include <net/fib_rules.h>
35#include <net/dn.h>
36#include <net/dn_route.h>
37#include <net/dn_fib.h>
38#include <net/dn_neigh.h>
39#include <net/dn_dev.h>
40
41struct dn_zone
42{
43 struct dn_zone *dz_next;
44 struct dn_fib_node **dz_hash;
45 int dz_nent;
46 int dz_divisor;
47 u32 dz_hashmask;
48#define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
49 int dz_order;
50 __le16 dz_mask;
51#define DZ_MASK(dz) ((dz)->dz_mask)
52};
53
54struct dn_hash
55{
56 struct dn_zone *dh_zones[17];
57 struct dn_zone *dh_zone_list;
58};
59
60#define dz_key_0(key) ((key).datum = 0)
61
62#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
63 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
64
65#define endfor_nexthops(fi) }
66
67#define DN_MAX_DIVISOR 1024
68#define DN_S_ZOMBIE 1
69#define DN_S_ACCESSED 2
70
71#define DN_FIB_SCAN(f, fp) \
72for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
73
74#define DN_FIB_SCAN_KEY(f, fp, key) \
75for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
76
77#define RT_TABLE_MIN 1
78#define DN_FIB_TABLE_HASHSZ 256
79static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
80static DEFINE_RWLOCK(dn_fib_tables_lock);
81
82static struct kmem_cache *dn_hash_kmem __read_mostly;
83static int dn_fib_hash_zombies;
84
85static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
86{
87 u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order);
88 h ^= (h >> 10);
89 h ^= (h >> 6);
90 h &= DZ_HASHMASK(dz);
91 return *(dn_fib_idx_t *)&h;
92}
93
94static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz)
95{
96 dn_fib_key_t k;
97 k.datum = dst & DZ_MASK(dz);
98 return k;
99}
100
101static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
102{
103 return &dz->dz_hash[dn_hash(key, dz).datum];
104}
105
106static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
107{
108 return dz->dz_hash[dn_hash(key, dz).datum];
109}
110
111static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
112{
113 return a.datum == b.datum;
114}
115
116static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
117{
118 return a.datum <= b.datum;
119}
120
121static inline void dn_rebuild_zone(struct dn_zone *dz,
122 struct dn_fib_node **old_ht,
123 int old_divisor)
124{
125 struct dn_fib_node *f, **fp, *next;
126 int i;
127
128 for(i = 0; i < old_divisor; i++) {
129 for(f = old_ht[i]; f; f = next) {
130 next = f->fn_next;
131 for(fp = dn_chain_p(f->fn_key, dz);
132 *fp && dn_key_leq((*fp)->fn_key, f->fn_key);
133 fp = &(*fp)->fn_next)
134 /* NOTHING */;
135 f->fn_next = *fp;
136 *fp = f;
137 }
138 }
139}
140
141static void dn_rehash_zone(struct dn_zone *dz)
142{
143 struct dn_fib_node **ht, **old_ht;
144 int old_divisor, new_divisor;
145 u32 new_hashmask;
146
147 old_divisor = dz->dz_divisor;
148
149 switch (old_divisor) {
150 case 16:
151 new_divisor = 256;
152 new_hashmask = 0xFF;
153 break;
154 default:
155 printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n",
156 old_divisor);
157 case 256:
158 new_divisor = 1024;
159 new_hashmask = 0x3FF;
160 break;
161 }
162
163 ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL);
164 if (ht == NULL)
165 return;
166
167 write_lock_bh(&dn_fib_tables_lock);
168 old_ht = dz->dz_hash;
169 dz->dz_hash = ht;
170 dz->dz_hashmask = new_hashmask;
171 dz->dz_divisor = new_divisor;
172 dn_rebuild_zone(dz, old_ht, old_divisor);
173 write_unlock_bh(&dn_fib_tables_lock);
174 kfree(old_ht);
175}
176
177static void dn_free_node(struct dn_fib_node *f)
178{
179 dn_fib_release_info(DN_FIB_INFO(f));
180 kmem_cache_free(dn_hash_kmem, f);
181}
182
183
184static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
185{
186 int i;
187 struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL);
188 if (!dz)
189 return NULL;
190
191 if (z) {
192 dz->dz_divisor = 16;
193 dz->dz_hashmask = 0x0F;
194 } else {
195 dz->dz_divisor = 1;
196 dz->dz_hashmask = 0;
197 }
198
199 dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL);
200 if (!dz->dz_hash) {
201 kfree(dz);
202 return NULL;
203 }
204
205 dz->dz_order = z;
206 dz->dz_mask = dnet_make_mask(z);
207
208 for(i = z + 1; i <= 16; i++)
209 if (table->dh_zones[i])
210 break;
211
212 write_lock_bh(&dn_fib_tables_lock);
213 if (i>16) {
214 dz->dz_next = table->dh_zone_list;
215 table->dh_zone_list = dz;
216 } else {
217 dz->dz_next = table->dh_zones[i]->dz_next;
218 table->dh_zones[i]->dz_next = dz;
219 }
220 table->dh_zones[z] = dz;
221 write_unlock_bh(&dn_fib_tables_lock);
222 return dz;
223}
224
225
226static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
227{
228 struct rtnexthop *nhp;
229 int nhlen;
230
231 if (attrs[RTA_PRIORITY] &&
232 nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
233 return 1;
234
235 if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
236 if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
237 (!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
238 return 0;
239 return 1;
240 }
241
242 if (!attrs[RTA_MULTIPATH])
243 return 0;
244
245 nhp = nla_data(attrs[RTA_MULTIPATH]);
246 nhlen = nla_len(attrs[RTA_MULTIPATH]);
247
248 for_nexthops(fi) {
249 int attrlen = nhlen - sizeof(struct rtnexthop);
250 __le16 gw;
251
252 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
253 return -EINVAL;
254 if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
255 return 1;
256 if (attrlen) {
257 struct nlattr *gw_attr;
258
259 gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
260 gw = gw_attr ? nla_get_le16(gw_attr) : 0;
261
262 if (gw && gw != nh->nh_gw)
263 return 1;
264 }
265 nhp = RTNH_NEXT(nhp);
266 } endfor_nexthops(fi);
267
268 return 0;
269}
270
271static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
272{
273 size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
274 + nla_total_size(4) /* RTA_TABLE */
275 + nla_total_size(2) /* RTA_DST */
276 + nla_total_size(4); /* RTA_PRIORITY */
277
278 /* space for nested metrics */
279 payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
280
281 if (fi->fib_nhs) {
282 /* Also handles the special case fib_nhs == 1 */
283
284 /* each nexthop is packed in an attribute */
285 size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
286
287 /* may contain a gateway attribute */
288 nhsize += nla_total_size(4);
289
290 /* all nexthops are packed in a nested attribute */
291 payload += nla_total_size(fi->fib_nhs * nhsize);
292 }
293
294 return payload;
295}
296
297static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
298 u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
299 struct dn_fib_info *fi, unsigned int flags)
300{
301 struct rtmsg *rtm;
302 struct nlmsghdr *nlh;
303
304 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
305 if (!nlh)
306 return -EMSGSIZE;
307
308 rtm = nlmsg_data(nlh);
309 rtm->rtm_family = AF_DECnet;
310 rtm->rtm_dst_len = dst_len;
311 rtm->rtm_src_len = 0;
312 rtm->rtm_tos = 0;
313 rtm->rtm_table = tb_id;
314 rtm->rtm_flags = fi->fib_flags;
315 rtm->rtm_scope = scope;
316 rtm->rtm_type = type;
317 rtm->rtm_protocol = fi->fib_protocol;
318
319 if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0)
320 goto errout;
321
322 if (rtm->rtm_dst_len &&
323 nla_put(skb, RTA_DST, 2, dst) < 0)
324 goto errout;
325
326 if (fi->fib_priority &&
327 nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0)
328 goto errout;
329
330 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
331 goto errout;
332
333 if (fi->fib_nhs == 1) {
334 if (fi->fib_nh->nh_gw &&
335 nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0)
336 goto errout;
337
338 if (fi->fib_nh->nh_oif &&
339 nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif) < 0)
340 goto errout;
341 }
342
343 if (fi->fib_nhs > 1) {
344 struct rtnexthop *nhp;
345 struct nlattr *mp_head;
346
347 if (!(mp_head = nla_nest_start(skb, RTA_MULTIPATH)))
348 goto errout;
349
350 for_nexthops(fi) {
351 if (!(nhp = nla_reserve_nohdr(skb, sizeof(*nhp))))
352 goto errout;
353
354 nhp->rtnh_flags = nh->nh_flags & 0xFF;
355 nhp->rtnh_hops = nh->nh_weight - 1;
356 nhp->rtnh_ifindex = nh->nh_oif;
357
358 if (nh->nh_gw &&
359 nla_put_le16(skb, RTA_GATEWAY, nh->nh_gw) < 0)
360 goto errout;
361
362 nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
363 } endfor_nexthops(fi);
364
365 nla_nest_end(skb, mp_head);
366 }
367
368 return nlmsg_end(skb, nlh);
369
370errout:
371 nlmsg_cancel(skb, nlh);
372 return -EMSGSIZE;
373}
374
375
376static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id,
377 struct nlmsghdr *nlh, struct netlink_skb_parms *req)
378{
379 struct sk_buff *skb;
380 u32 portid = req ? req->portid : 0;
381 int err = -ENOBUFS;
382
383 skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL);
384 if (skb == NULL)
385 goto errout;
386
387 err = dn_fib_dump_info(skb, portid, nlh->nlmsg_seq, event, tb_id,
388 f->fn_type, f->fn_scope, &f->fn_key, z,
389 DN_FIB_INFO(f), 0);
390 if (err < 0) {
391 /* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */
392 WARN_ON(err == -EMSGSIZE);
393 kfree_skb(skb);
394 goto errout;
395 }
396 rtnl_notify(skb, &init_net, portid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL);
397 return;
398errout:
399 if (err < 0)
400 rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err);
401}
402
403static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
404 struct netlink_callback *cb,
405 struct dn_fib_table *tb,
406 struct dn_zone *dz,
407 struct dn_fib_node *f)
408{
409 int i, s_i;
410
411 s_i = cb->args[4];
412 for(i = 0; f; i++, f = f->fn_next) {
413 if (i < s_i)
414 continue;
415 if (f->fn_state & DN_S_ZOMBIE)
416 continue;
417 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).portid,
418 cb->nlh->nlmsg_seq,
419 RTM_NEWROUTE,
420 tb->n,
421 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
422 f->fn_scope, &f->fn_key, dz->dz_order,
423 f->fn_info, NLM_F_MULTI) < 0) {
424 cb->args[4] = i;
425 return -1;
426 }
427 }
428 cb->args[4] = i;
429 return skb->len;
430}
431
432static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
433 struct netlink_callback *cb,
434 struct dn_fib_table *tb,
435 struct dn_zone *dz)
436{
437 int h, s_h;
438
439 s_h = cb->args[3];
440 for(h = 0; h < dz->dz_divisor; h++) {
441 if (h < s_h)
442 continue;
443 if (h > s_h)
444 memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0]));
445 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
446 continue;
447 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
448 cb->args[3] = h;
449 return -1;
450 }
451 }
452 cb->args[3] = h;
453 return skb->len;
454}
455
456static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
457 struct netlink_callback *cb)
458{
459 int m, s_m;
460 struct dn_zone *dz;
461 struct dn_hash *table = (struct dn_hash *)tb->data;
462
463 s_m = cb->args[2];
464 read_lock(&dn_fib_tables_lock);
465 for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
466 if (m < s_m)
467 continue;
468 if (m > s_m)
469 memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
470
471 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
472 cb->args[2] = m;
473 read_unlock(&dn_fib_tables_lock);
474 return -1;
475 }
476 }
477 read_unlock(&dn_fib_tables_lock);
478 cb->args[2] = m;
479
480 return skb->len;
481}
482
483int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
484{
485 struct net *net = sock_net(skb->sk);
486 unsigned int h, s_h;
487 unsigned int e = 0, s_e;
488 struct dn_fib_table *tb;
489 int dumped = 0;
490
491 if (!net_eq(net, &init_net))
492 return 0;
493
494 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
495 ((struct rtmsg *)nlmsg_data(cb->nlh))->rtm_flags&RTM_F_CLONED)
496 return dn_cache_dump(skb, cb);
497
498 s_h = cb->args[0];
499 s_e = cb->args[1];
500
501 for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) {
502 e = 0;
503 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist) {
504 if (e < s_e)
505 goto next;
506 if (dumped)
507 memset(&cb->args[2], 0, sizeof(cb->args) -
508 2 * sizeof(cb->args[0]));
509 if (tb->dump(tb, skb, cb) < 0)
510 goto out;
511 dumped = 1;
512next:
513 e++;
514 }
515 }
516out:
517 cb->args[1] = e;
518 cb->args[0] = h;
519
520 return skb->len;
521}
522
523static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
524 struct nlmsghdr *n, struct netlink_skb_parms *req)
525{
526 struct dn_hash *table = (struct dn_hash *)tb->data;
527 struct dn_fib_node *new_f, *f, **fp, **del_fp;
528 struct dn_zone *dz;
529 struct dn_fib_info *fi;
530 int z = r->rtm_dst_len;
531 int type = r->rtm_type;
532 dn_fib_key_t key;
533 int err;
534
535 if (z > 16)
536 return -EINVAL;
537
538 dz = table->dh_zones[z];
539 if (!dz && !(dz = dn_new_zone(table, z)))
540 return -ENOBUFS;
541
542 dz_key_0(key);
543 if (attrs[RTA_DST]) {
544 __le16 dst = nla_get_le16(attrs[RTA_DST]);
545 if (dst & ~DZ_MASK(dz))
546 return -EINVAL;
547 key = dz_key(dst, dz);
548 }
549
550 if ((fi = dn_fib_create_info(r, attrs, n, &err)) == NULL)
551 return err;
552
553 if (dz->dz_nent > (dz->dz_divisor << 2) &&
554 dz->dz_divisor > DN_MAX_DIVISOR &&
555 (z==16 || (1<<z) > dz->dz_divisor))
556 dn_rehash_zone(dz);
557
558 fp = dn_chain_p(key, dz);
559
560 DN_FIB_SCAN(f, fp) {
561 if (dn_key_leq(key, f->fn_key))
562 break;
563 }
564
565 del_fp = NULL;
566
567 if (f && (f->fn_state & DN_S_ZOMBIE) &&
568 dn_key_eq(f->fn_key, key)) {
569 del_fp = fp;
570 fp = &f->fn_next;
571 f = *fp;
572 goto create;
573 }
574
575 DN_FIB_SCAN_KEY(f, fp, key) {
576 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
577 break;
578 }
579
580 if (f && dn_key_eq(f->fn_key, key) &&
581 fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
582 struct dn_fib_node **ins_fp;
583
584 err = -EEXIST;
585 if (n->nlmsg_flags & NLM_F_EXCL)
586 goto out;
587
588 if (n->nlmsg_flags & NLM_F_REPLACE) {
589 del_fp = fp;
590 fp = &f->fn_next;
591 f = *fp;
592 goto replace;
593 }
594
595 ins_fp = fp;
596 err = -EEXIST;
597
598 DN_FIB_SCAN_KEY(f, fp, key) {
599 if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
600 break;
601 if (f->fn_type == type &&
602 f->fn_scope == r->rtm_scope &&
603 DN_FIB_INFO(f) == fi)
604 goto out;
605 }
606
607 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
608 fp = ins_fp;
609 f = *fp;
610 }
611 }
612
613create:
614 err = -ENOENT;
615 if (!(n->nlmsg_flags & NLM_F_CREATE))
616 goto out;
617
618replace:
619 err = -ENOBUFS;
620 new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL);
621 if (new_f == NULL)
622 goto out;
623
624 new_f->fn_key = key;
625 new_f->fn_type = type;
626 new_f->fn_scope = r->rtm_scope;
627 DN_FIB_INFO(new_f) = fi;
628
629 new_f->fn_next = f;
630 write_lock_bh(&dn_fib_tables_lock);
631 *fp = new_f;
632 write_unlock_bh(&dn_fib_tables_lock);
633 dz->dz_nent++;
634
635 if (del_fp) {
636 f = *del_fp;
637 write_lock_bh(&dn_fib_tables_lock);
638 *del_fp = f->fn_next;
639 write_unlock_bh(&dn_fib_tables_lock);
640
641 if (!(f->fn_state & DN_S_ZOMBIE))
642 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
643 if (f->fn_state & DN_S_ACCESSED)
644 dn_rt_cache_flush(-1);
645 dn_free_node(f);
646 dz->dz_nent--;
647 } else {
648 dn_rt_cache_flush(-1);
649 }
650
651 dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
652
653 return 0;
654out:
655 dn_fib_release_info(fi);
656 return err;
657}
658
659
660static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct nlattr *attrs[],
661 struct nlmsghdr *n, struct netlink_skb_parms *req)
662{
663 struct dn_hash *table = (struct dn_hash*)tb->data;
664 struct dn_fib_node **fp, **del_fp, *f;
665 int z = r->rtm_dst_len;
666 struct dn_zone *dz;
667 dn_fib_key_t key;
668 int matched;
669
670
671 if (z > 16)
672 return -EINVAL;
673
674 if ((dz = table->dh_zones[z]) == NULL)
675 return -ESRCH;
676
677 dz_key_0(key);
678 if (attrs[RTA_DST]) {
679 __le16 dst = nla_get_le16(attrs[RTA_DST]);
680 if (dst & ~DZ_MASK(dz))
681 return -EINVAL;
682 key = dz_key(dst, dz);
683 }
684
685 fp = dn_chain_p(key, dz);
686
687 DN_FIB_SCAN(f, fp) {
688 if (dn_key_eq(f->fn_key, key))
689 break;
690 if (dn_key_leq(key, f->fn_key))
691 return -ESRCH;
692 }
693
694 matched = 0;
695 del_fp = NULL;
696 DN_FIB_SCAN_KEY(f, fp, key) {
697 struct dn_fib_info *fi = DN_FIB_INFO(f);
698
699 if (f->fn_state & DN_S_ZOMBIE)
700 return -ESRCH;
701
702 matched++;
703
704 if (del_fp == NULL &&
705 (!r->rtm_type || f->fn_type == r->rtm_type) &&
706 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
707 (!r->rtm_protocol ||
708 fi->fib_protocol == r->rtm_protocol) &&
709 dn_fib_nh_match(r, n, attrs, fi) == 0)
710 del_fp = fp;
711 }
712
713 if (del_fp) {
714 f = *del_fp;
715 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
716
717 if (matched != 1) {
718 write_lock_bh(&dn_fib_tables_lock);
719 *del_fp = f->fn_next;
720 write_unlock_bh(&dn_fib_tables_lock);
721
722 if (f->fn_state & DN_S_ACCESSED)
723 dn_rt_cache_flush(-1);
724 dn_free_node(f);
725 dz->dz_nent--;
726 } else {
727 f->fn_state |= DN_S_ZOMBIE;
728 if (f->fn_state & DN_S_ACCESSED) {
729 f->fn_state &= ~DN_S_ACCESSED;
730 dn_rt_cache_flush(-1);
731 }
732 if (++dn_fib_hash_zombies > 128)
733 dn_fib_flush();
734 }
735
736 return 0;
737 }
738
739 return -ESRCH;
740}
741
742static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
743{
744 int found = 0;
745 struct dn_fib_node *f;
746
747 while((f = *fp) != NULL) {
748 struct dn_fib_info *fi = DN_FIB_INFO(f);
749
750 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
751 write_lock_bh(&dn_fib_tables_lock);
752 *fp = f->fn_next;
753 write_unlock_bh(&dn_fib_tables_lock);
754
755 dn_free_node(f);
756 found++;
757 continue;
758 }
759 fp = &f->fn_next;
760 }
761
762 return found;
763}
764
765static int dn_fib_table_flush(struct dn_fib_table *tb)
766{
767 struct dn_hash *table = (struct dn_hash *)tb->data;
768 struct dn_zone *dz;
769 int found = 0;
770
771 dn_fib_hash_zombies = 0;
772 for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
773 int i;
774 int tmp = 0;
775 for(i = dz->dz_divisor-1; i >= 0; i--)
776 tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
777 dz->dz_nent -= tmp;
778 found += tmp;
779 }
780
781 return found;
782}
783
784static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res)
785{
786 int err;
787 struct dn_zone *dz;
788 struct dn_hash *t = (struct dn_hash *)tb->data;
789
790 read_lock(&dn_fib_tables_lock);
791 for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
792 struct dn_fib_node *f;
793 dn_fib_key_t k = dz_key(flp->daddr, dz);
794
795 for(f = dz_chain(k, dz); f; f = f->fn_next) {
796 if (!dn_key_eq(k, f->fn_key)) {
797 if (dn_key_leq(k, f->fn_key))
798 break;
799 else
800 continue;
801 }
802
803 f->fn_state |= DN_S_ACCESSED;
804
805 if (f->fn_state&DN_S_ZOMBIE)
806 continue;
807
808 if (f->fn_scope < flp->flowidn_scope)
809 continue;
810
811 err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
812
813 if (err == 0) {
814 res->type = f->fn_type;
815 res->scope = f->fn_scope;
816 res->prefixlen = dz->dz_order;
817 goto out;
818 }
819 if (err < 0)
820 goto out;
821 }
822 }
823 err = 1;
824out:
825 read_unlock(&dn_fib_tables_lock);
826 return err;
827}
828
829
830struct dn_fib_table *dn_fib_get_table(u32 n, int create)
831{
832 struct dn_fib_table *t;
833 unsigned int h;
834
835 if (n < RT_TABLE_MIN)
836 return NULL;
837
838 if (n > RT_TABLE_MAX)
839 return NULL;
840
841 h = n & (DN_FIB_TABLE_HASHSZ - 1);
842 rcu_read_lock();
843 hlist_for_each_entry_rcu(t, &dn_fib_table_hash[h], hlist) {
844 if (t->n == n) {
845 rcu_read_unlock();
846 return t;
847 }
848 }
849 rcu_read_unlock();
850
851 if (!create)
852 return NULL;
853
854 if (in_interrupt()) {
855 net_dbg_ratelimited("DECnet: BUG! Attempt to create routing table from interrupt\n");
856 return NULL;
857 }
858
859 t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash),
860 GFP_KERNEL);
861 if (t == NULL)
862 return NULL;
863
864 t->n = n;
865 t->insert = dn_fib_table_insert;
866 t->delete = dn_fib_table_delete;
867 t->lookup = dn_fib_table_lookup;
868 t->flush = dn_fib_table_flush;
869 t->dump = dn_fib_table_dump;
870 hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]);
871
872 return t;
873}
874
875struct dn_fib_table *dn_fib_empty_table(void)
876{
877 u32 id;
878
879 for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
880 if (dn_fib_get_table(id, 0) == NULL)
881 return dn_fib_get_table(id, 1);
882 return NULL;
883}
884
885void dn_fib_flush(void)
886{
887 int flushed = 0;
888 struct dn_fib_table *tb;
889 unsigned int h;
890
891 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
892 hlist_for_each_entry(tb, &dn_fib_table_hash[h], hlist)
893 flushed += tb->flush(tb);
894 }
895
896 if (flushed)
897 dn_rt_cache_flush(-1);
898}
899
900void __init dn_fib_table_init(void)
901{
902 dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
903 sizeof(struct dn_fib_info),
904 0, SLAB_HWCACHE_ALIGN,
905 NULL);
906}
907
908void __exit dn_fib_table_cleanup(void)
909{
910 struct dn_fib_table *t;
911 struct hlist_node *next;
912 unsigned int h;
913
914 write_lock(&dn_fib_tables_lock);
915 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
916 hlist_for_each_entry_safe(t, next, &dn_fib_table_hash[h],
917 hlist) {
918 hlist_del(&t->hlist);
919 kfree(t);
920 }
921 }
922 write_unlock(&dn_fib_tables_lock);
923}