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/netlink.h>
23 #include <linux/rtnetlink.h>
24 #include <linux/proc_fs.h>
25 #include <linux/netdevice.h>
26 #include <linux/timer.h>
27 #include <linux/spinlock.h>
28 #include <linux/atomic.h>
29 #include <asm/uaccess.h>
30 #include <linux/route.h> /* RTF_xxx */
31 #include <net/neighbour.h>
32 #include <net/netlink.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
42 struct 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
55 struct 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) \
73 for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
74
75 #define DN_FIB_SCAN_KEY(f, fp, key) \
76 for( ; ((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
80 static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
81 static DEFINE_RWLOCK(dn_fib_tables_lock);
82
83 static struct kmem_cache *dn_hash_kmem __read_mostly;
84 static int dn_fib_hash_zombies;
85
dn_hash(dn_fib_key_t key,struct dn_zone * dz)86 static 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
dz_key(__le16 dst,struct dn_zone * dz)95 static 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
dn_chain_p(dn_fib_key_t key,struct dn_zone * dz)102 static 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
dz_chain(dn_fib_key_t key,struct dn_zone * dz)107 static 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
dn_key_eq(dn_fib_key_t a,dn_fib_key_t b)112 static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
113 {
114 return a.datum == b.datum;
115 }
116
dn_key_leq(dn_fib_key_t a,dn_fib_key_t b)117 static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
118 {
119 return a.datum <= b.datum;
120 }
121
dn_rebuild_zone(struct dn_zone * dz,struct dn_fib_node ** old_ht,int old_divisor)122 static 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
dn_rehash_zone(struct dn_zone * dz)142 static 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
dn_free_node(struct dn_fib_node * f)178 static 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
dn_new_zone(struct dn_hash * table,int z)185 static 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
dn_fib_nh_match(struct rtmsg * r,struct nlmsghdr * nlh,struct dn_kern_rta * rta,struct dn_fib_info * fi)227 static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct dn_kern_rta *rta, struct dn_fib_info *fi)
228 {
229 struct rtnexthop *nhp;
230 int nhlen;
231
232 if (rta->rta_priority && *rta->rta_priority != fi->fib_priority)
233 return 1;
234
235 if (rta->rta_oif || rta->rta_gw) {
236 if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
237 (!rta->rta_gw || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 2) == 0))
238 return 0;
239 return 1;
240 }
241
242 if (rta->rta_mp == NULL)
243 return 0;
244
245 nhp = RTA_DATA(rta->rta_mp);
246 nhlen = RTA_PAYLOAD(rta->rta_mp);
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 gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
258
259 if (gw && gw != nh->nh_gw)
260 return 1;
261 }
262 nhp = RTNH_NEXT(nhp);
263 } endfor_nexthops(fi);
264
265 return 0;
266 }
267
dn_fib_nlmsg_size(struct dn_fib_info * fi)268 static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
269 {
270 size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
271 + nla_total_size(4) /* RTA_TABLE */
272 + nla_total_size(2) /* RTA_DST */
273 + nla_total_size(4); /* RTA_PRIORITY */
274
275 /* space for nested metrics */
276 payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
277
278 if (fi->fib_nhs) {
279 /* Also handles the special case fib_nhs == 1 */
280
281 /* each nexthop is packed in an attribute */
282 size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
283
284 /* may contain a gateway attribute */
285 nhsize += nla_total_size(4);
286
287 /* all nexthops are packed in a nested attribute */
288 payload += nla_total_size(fi->fib_nhs * nhsize);
289 }
290
291 return payload;
292 }
293
dn_fib_dump_info(struct sk_buff * skb,u32 pid,u32 seq,int event,u32 tb_id,u8 type,u8 scope,void * dst,int dst_len,struct dn_fib_info * fi,unsigned int flags)294 static int dn_fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
295 u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
296 struct dn_fib_info *fi, unsigned int flags)
297 {
298 struct rtmsg *rtm;
299 struct nlmsghdr *nlh;
300 unsigned char *b = skb_tail_pointer(skb);
301
302 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*rtm), flags);
303 rtm = NLMSG_DATA(nlh);
304 rtm->rtm_family = AF_DECnet;
305 rtm->rtm_dst_len = dst_len;
306 rtm->rtm_src_len = 0;
307 rtm->rtm_tos = 0;
308 rtm->rtm_table = tb_id;
309 RTA_PUT_U32(skb, RTA_TABLE, tb_id);
310 rtm->rtm_flags = fi->fib_flags;
311 rtm->rtm_scope = scope;
312 rtm->rtm_type = type;
313 if (rtm->rtm_dst_len)
314 RTA_PUT(skb, RTA_DST, 2, dst);
315 rtm->rtm_protocol = fi->fib_protocol;
316 if (fi->fib_priority)
317 RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
318 if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
319 goto rtattr_failure;
320 if (fi->fib_nhs == 1) {
321 if (fi->fib_nh->nh_gw)
322 RTA_PUT(skb, RTA_GATEWAY, 2, &fi->fib_nh->nh_gw);
323 if (fi->fib_nh->nh_oif)
324 RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
325 }
326 if (fi->fib_nhs > 1) {
327 struct rtnexthop *nhp;
328 struct rtattr *mp_head;
329 if (skb_tailroom(skb) <= RTA_SPACE(0))
330 goto rtattr_failure;
331 mp_head = (struct rtattr *)skb_put(skb, RTA_SPACE(0));
332
333 for_nexthops(fi) {
334 if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
335 goto rtattr_failure;
336 nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
337 nhp->rtnh_flags = nh->nh_flags & 0xFF;
338 nhp->rtnh_hops = nh->nh_weight - 1;
339 nhp->rtnh_ifindex = nh->nh_oif;
340 if (nh->nh_gw)
341 RTA_PUT(skb, RTA_GATEWAY, 2, &nh->nh_gw);
342 nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
343 } endfor_nexthops(fi);
344 mp_head->rta_type = RTA_MULTIPATH;
345 mp_head->rta_len = skb_tail_pointer(skb) - (u8 *)mp_head;
346 }
347
348 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
349 return skb->len;
350
351
352 nlmsg_failure:
353 rtattr_failure:
354 nlmsg_trim(skb, b);
355 return -EMSGSIZE;
356 }
357
358
dn_rtmsg_fib(int event,struct dn_fib_node * f,int z,u32 tb_id,struct nlmsghdr * nlh,struct netlink_skb_parms * req)359 static void dn_rtmsg_fib(int event, struct dn_fib_node *f, int z, u32 tb_id,
360 struct nlmsghdr *nlh, struct netlink_skb_parms *req)
361 {
362 struct sk_buff *skb;
363 u32 pid = req ? req->pid : 0;
364 int err = -ENOBUFS;
365
366 skb = nlmsg_new(dn_fib_nlmsg_size(DN_FIB_INFO(f)), GFP_KERNEL);
367 if (skb == NULL)
368 goto errout;
369
370 err = dn_fib_dump_info(skb, pid, nlh->nlmsg_seq, event, tb_id,
371 f->fn_type, f->fn_scope, &f->fn_key, z,
372 DN_FIB_INFO(f), 0);
373 if (err < 0) {
374 /* -EMSGSIZE implies BUG in dn_fib_nlmsg_size() */
375 WARN_ON(err == -EMSGSIZE);
376 kfree_skb(skb);
377 goto errout;
378 }
379 rtnl_notify(skb, &init_net, pid, RTNLGRP_DECnet_ROUTE, nlh, GFP_KERNEL);
380 return;
381 errout:
382 if (err < 0)
383 rtnl_set_sk_err(&init_net, RTNLGRP_DECnet_ROUTE, err);
384 }
385
dn_hash_dump_bucket(struct sk_buff * skb,struct netlink_callback * cb,struct dn_fib_table * tb,struct dn_zone * dz,struct dn_fib_node * f)386 static __inline__ int dn_hash_dump_bucket(struct sk_buff *skb,
387 struct netlink_callback *cb,
388 struct dn_fib_table *tb,
389 struct dn_zone *dz,
390 struct dn_fib_node *f)
391 {
392 int i, s_i;
393
394 s_i = cb->args[4];
395 for(i = 0; f; i++, f = f->fn_next) {
396 if (i < s_i)
397 continue;
398 if (f->fn_state & DN_S_ZOMBIE)
399 continue;
400 if (dn_fib_dump_info(skb, NETLINK_CB(cb->skb).pid,
401 cb->nlh->nlmsg_seq,
402 RTM_NEWROUTE,
403 tb->n,
404 (f->fn_state & DN_S_ZOMBIE) ? 0 : f->fn_type,
405 f->fn_scope, &f->fn_key, dz->dz_order,
406 f->fn_info, NLM_F_MULTI) < 0) {
407 cb->args[4] = i;
408 return -1;
409 }
410 }
411 cb->args[4] = i;
412 return skb->len;
413 }
414
dn_hash_dump_zone(struct sk_buff * skb,struct netlink_callback * cb,struct dn_fib_table * tb,struct dn_zone * dz)415 static __inline__ int dn_hash_dump_zone(struct sk_buff *skb,
416 struct netlink_callback *cb,
417 struct dn_fib_table *tb,
418 struct dn_zone *dz)
419 {
420 int h, s_h;
421
422 s_h = cb->args[3];
423 for(h = 0; h < dz->dz_divisor; h++) {
424 if (h < s_h)
425 continue;
426 if (h > s_h)
427 memset(&cb->args[4], 0, sizeof(cb->args) - 4*sizeof(cb->args[0]));
428 if (dz->dz_hash == NULL || dz->dz_hash[h] == NULL)
429 continue;
430 if (dn_hash_dump_bucket(skb, cb, tb, dz, dz->dz_hash[h]) < 0) {
431 cb->args[3] = h;
432 return -1;
433 }
434 }
435 cb->args[3] = h;
436 return skb->len;
437 }
438
dn_fib_table_dump(struct dn_fib_table * tb,struct sk_buff * skb,struct netlink_callback * cb)439 static int dn_fib_table_dump(struct dn_fib_table *tb, struct sk_buff *skb,
440 struct netlink_callback *cb)
441 {
442 int m, s_m;
443 struct dn_zone *dz;
444 struct dn_hash *table = (struct dn_hash *)tb->data;
445
446 s_m = cb->args[2];
447 read_lock(&dn_fib_tables_lock);
448 for(dz = table->dh_zone_list, m = 0; dz; dz = dz->dz_next, m++) {
449 if (m < s_m)
450 continue;
451 if (m > s_m)
452 memset(&cb->args[3], 0, sizeof(cb->args) - 3*sizeof(cb->args[0]));
453
454 if (dn_hash_dump_zone(skb, cb, tb, dz) < 0) {
455 cb->args[2] = m;
456 read_unlock(&dn_fib_tables_lock);
457 return -1;
458 }
459 }
460 read_unlock(&dn_fib_tables_lock);
461 cb->args[2] = m;
462
463 return skb->len;
464 }
465
dn_fib_dump(struct sk_buff * skb,struct netlink_callback * cb)466 int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
467 {
468 struct net *net = sock_net(skb->sk);
469 unsigned int h, s_h;
470 unsigned int e = 0, s_e;
471 struct dn_fib_table *tb;
472 struct hlist_node *node;
473 int dumped = 0;
474
475 if (!net_eq(net, &init_net))
476 return 0;
477
478 if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) &&
479 ((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED)
480 return dn_cache_dump(skb, cb);
481
482 s_h = cb->args[0];
483 s_e = cb->args[1];
484
485 for (h = s_h; h < DN_FIB_TABLE_HASHSZ; h++, s_h = 0) {
486 e = 0;
487 hlist_for_each_entry(tb, node, &dn_fib_table_hash[h], hlist) {
488 if (e < s_e)
489 goto next;
490 if (dumped)
491 memset(&cb->args[2], 0, sizeof(cb->args) -
492 2 * sizeof(cb->args[0]));
493 if (tb->dump(tb, skb, cb) < 0)
494 goto out;
495 dumped = 1;
496 next:
497 e++;
498 }
499 }
500 out:
501 cb->args[1] = e;
502 cb->args[0] = h;
503
504 return skb->len;
505 }
506
dn_fib_table_insert(struct dn_fib_table * tb,struct rtmsg * r,struct dn_kern_rta * rta,struct nlmsghdr * n,struct netlink_skb_parms * req)507 static int dn_fib_table_insert(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
508 {
509 struct dn_hash *table = (struct dn_hash *)tb->data;
510 struct dn_fib_node *new_f, *f, **fp, **del_fp;
511 struct dn_zone *dz;
512 struct dn_fib_info *fi;
513 int z = r->rtm_dst_len;
514 int type = r->rtm_type;
515 dn_fib_key_t key;
516 int err;
517
518 if (z > 16)
519 return -EINVAL;
520
521 dz = table->dh_zones[z];
522 if (!dz && !(dz = dn_new_zone(table, z)))
523 return -ENOBUFS;
524
525 dz_key_0(key);
526 if (rta->rta_dst) {
527 __le16 dst;
528 memcpy(&dst, rta->rta_dst, 2);
529 if (dst & ~DZ_MASK(dz))
530 return -EINVAL;
531 key = dz_key(dst, dz);
532 }
533
534 if ((fi = dn_fib_create_info(r, rta, n, &err)) == NULL)
535 return err;
536
537 if (dz->dz_nent > (dz->dz_divisor << 2) &&
538 dz->dz_divisor > DN_MAX_DIVISOR &&
539 (z==16 || (1<<z) > dz->dz_divisor))
540 dn_rehash_zone(dz);
541
542 fp = dn_chain_p(key, dz);
543
544 DN_FIB_SCAN(f, fp) {
545 if (dn_key_leq(key, f->fn_key))
546 break;
547 }
548
549 del_fp = NULL;
550
551 if (f && (f->fn_state & DN_S_ZOMBIE) &&
552 dn_key_eq(f->fn_key, key)) {
553 del_fp = fp;
554 fp = &f->fn_next;
555 f = *fp;
556 goto create;
557 }
558
559 DN_FIB_SCAN_KEY(f, fp, key) {
560 if (fi->fib_priority <= DN_FIB_INFO(f)->fib_priority)
561 break;
562 }
563
564 if (f && dn_key_eq(f->fn_key, key) &&
565 fi->fib_priority == DN_FIB_INFO(f)->fib_priority) {
566 struct dn_fib_node **ins_fp;
567
568 err = -EEXIST;
569 if (n->nlmsg_flags & NLM_F_EXCL)
570 goto out;
571
572 if (n->nlmsg_flags & NLM_F_REPLACE) {
573 del_fp = fp;
574 fp = &f->fn_next;
575 f = *fp;
576 goto replace;
577 }
578
579 ins_fp = fp;
580 err = -EEXIST;
581
582 DN_FIB_SCAN_KEY(f, fp, key) {
583 if (fi->fib_priority != DN_FIB_INFO(f)->fib_priority)
584 break;
585 if (f->fn_type == type &&
586 f->fn_scope == r->rtm_scope &&
587 DN_FIB_INFO(f) == fi)
588 goto out;
589 }
590
591 if (!(n->nlmsg_flags & NLM_F_APPEND)) {
592 fp = ins_fp;
593 f = *fp;
594 }
595 }
596
597 create:
598 err = -ENOENT;
599 if (!(n->nlmsg_flags & NLM_F_CREATE))
600 goto out;
601
602 replace:
603 err = -ENOBUFS;
604 new_f = kmem_cache_zalloc(dn_hash_kmem, GFP_KERNEL);
605 if (new_f == NULL)
606 goto out;
607
608 new_f->fn_key = key;
609 new_f->fn_type = type;
610 new_f->fn_scope = r->rtm_scope;
611 DN_FIB_INFO(new_f) = fi;
612
613 new_f->fn_next = f;
614 write_lock_bh(&dn_fib_tables_lock);
615 *fp = new_f;
616 write_unlock_bh(&dn_fib_tables_lock);
617 dz->dz_nent++;
618
619 if (del_fp) {
620 f = *del_fp;
621 write_lock_bh(&dn_fib_tables_lock);
622 *del_fp = f->fn_next;
623 write_unlock_bh(&dn_fib_tables_lock);
624
625 if (!(f->fn_state & DN_S_ZOMBIE))
626 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
627 if (f->fn_state & DN_S_ACCESSED)
628 dn_rt_cache_flush(-1);
629 dn_free_node(f);
630 dz->dz_nent--;
631 } else {
632 dn_rt_cache_flush(-1);
633 }
634
635 dn_rtmsg_fib(RTM_NEWROUTE, new_f, z, tb->n, n, req);
636
637 return 0;
638 out:
639 dn_fib_release_info(fi);
640 return err;
641 }
642
643
dn_fib_table_delete(struct dn_fib_table * tb,struct rtmsg * r,struct dn_kern_rta * rta,struct nlmsghdr * n,struct netlink_skb_parms * req)644 static int dn_fib_table_delete(struct dn_fib_table *tb, struct rtmsg *r, struct dn_kern_rta *rta, struct nlmsghdr *n, struct netlink_skb_parms *req)
645 {
646 struct dn_hash *table = (struct dn_hash*)tb->data;
647 struct dn_fib_node **fp, **del_fp, *f;
648 int z = r->rtm_dst_len;
649 struct dn_zone *dz;
650 dn_fib_key_t key;
651 int matched;
652
653
654 if (z > 16)
655 return -EINVAL;
656
657 if ((dz = table->dh_zones[z]) == NULL)
658 return -ESRCH;
659
660 dz_key_0(key);
661 if (rta->rta_dst) {
662 __le16 dst;
663 memcpy(&dst, rta->rta_dst, 2);
664 if (dst & ~DZ_MASK(dz))
665 return -EINVAL;
666 key = dz_key(dst, dz);
667 }
668
669 fp = dn_chain_p(key, dz);
670
671 DN_FIB_SCAN(f, fp) {
672 if (dn_key_eq(f->fn_key, key))
673 break;
674 if (dn_key_leq(key, f->fn_key))
675 return -ESRCH;
676 }
677
678 matched = 0;
679 del_fp = NULL;
680 DN_FIB_SCAN_KEY(f, fp, key) {
681 struct dn_fib_info *fi = DN_FIB_INFO(f);
682
683 if (f->fn_state & DN_S_ZOMBIE)
684 return -ESRCH;
685
686 matched++;
687
688 if (del_fp == NULL &&
689 (!r->rtm_type || f->fn_type == r->rtm_type) &&
690 (r->rtm_scope == RT_SCOPE_NOWHERE || f->fn_scope == r->rtm_scope) &&
691 (!r->rtm_protocol ||
692 fi->fib_protocol == r->rtm_protocol) &&
693 dn_fib_nh_match(r, n, rta, fi) == 0)
694 del_fp = fp;
695 }
696
697 if (del_fp) {
698 f = *del_fp;
699 dn_rtmsg_fib(RTM_DELROUTE, f, z, tb->n, n, req);
700
701 if (matched != 1) {
702 write_lock_bh(&dn_fib_tables_lock);
703 *del_fp = f->fn_next;
704 write_unlock_bh(&dn_fib_tables_lock);
705
706 if (f->fn_state & DN_S_ACCESSED)
707 dn_rt_cache_flush(-1);
708 dn_free_node(f);
709 dz->dz_nent--;
710 } else {
711 f->fn_state |= DN_S_ZOMBIE;
712 if (f->fn_state & DN_S_ACCESSED) {
713 f->fn_state &= ~DN_S_ACCESSED;
714 dn_rt_cache_flush(-1);
715 }
716 if (++dn_fib_hash_zombies > 128)
717 dn_fib_flush();
718 }
719
720 return 0;
721 }
722
723 return -ESRCH;
724 }
725
dn_flush_list(struct dn_fib_node ** fp,int z,struct dn_hash * table)726 static inline int dn_flush_list(struct dn_fib_node **fp, int z, struct dn_hash *table)
727 {
728 int found = 0;
729 struct dn_fib_node *f;
730
731 while((f = *fp) != NULL) {
732 struct dn_fib_info *fi = DN_FIB_INFO(f);
733
734 if (fi && ((f->fn_state & DN_S_ZOMBIE) || (fi->fib_flags & RTNH_F_DEAD))) {
735 write_lock_bh(&dn_fib_tables_lock);
736 *fp = f->fn_next;
737 write_unlock_bh(&dn_fib_tables_lock);
738
739 dn_free_node(f);
740 found++;
741 continue;
742 }
743 fp = &f->fn_next;
744 }
745
746 return found;
747 }
748
dn_fib_table_flush(struct dn_fib_table * tb)749 static int dn_fib_table_flush(struct dn_fib_table *tb)
750 {
751 struct dn_hash *table = (struct dn_hash *)tb->data;
752 struct dn_zone *dz;
753 int found = 0;
754
755 dn_fib_hash_zombies = 0;
756 for(dz = table->dh_zone_list; dz; dz = dz->dz_next) {
757 int i;
758 int tmp = 0;
759 for(i = dz->dz_divisor-1; i >= 0; i--)
760 tmp += dn_flush_list(&dz->dz_hash[i], dz->dz_order, table);
761 dz->dz_nent -= tmp;
762 found += tmp;
763 }
764
765 return found;
766 }
767
dn_fib_table_lookup(struct dn_fib_table * tb,const struct flowidn * flp,struct dn_fib_res * res)768 static int dn_fib_table_lookup(struct dn_fib_table *tb, const struct flowidn *flp, struct dn_fib_res *res)
769 {
770 int err;
771 struct dn_zone *dz;
772 struct dn_hash *t = (struct dn_hash *)tb->data;
773
774 read_lock(&dn_fib_tables_lock);
775 for(dz = t->dh_zone_list; dz; dz = dz->dz_next) {
776 struct dn_fib_node *f;
777 dn_fib_key_t k = dz_key(flp->daddr, dz);
778
779 for(f = dz_chain(k, dz); f; f = f->fn_next) {
780 if (!dn_key_eq(k, f->fn_key)) {
781 if (dn_key_leq(k, f->fn_key))
782 break;
783 else
784 continue;
785 }
786
787 f->fn_state |= DN_S_ACCESSED;
788
789 if (f->fn_state&DN_S_ZOMBIE)
790 continue;
791
792 if (f->fn_scope < flp->flowidn_scope)
793 continue;
794
795 err = dn_fib_semantic_match(f->fn_type, DN_FIB_INFO(f), flp, res);
796
797 if (err == 0) {
798 res->type = f->fn_type;
799 res->scope = f->fn_scope;
800 res->prefixlen = dz->dz_order;
801 goto out;
802 }
803 if (err < 0)
804 goto out;
805 }
806 }
807 err = 1;
808 out:
809 read_unlock(&dn_fib_tables_lock);
810 return err;
811 }
812
813
dn_fib_get_table(u32 n,int create)814 struct dn_fib_table *dn_fib_get_table(u32 n, int create)
815 {
816 struct dn_fib_table *t;
817 struct hlist_node *node;
818 unsigned int h;
819
820 if (n < RT_TABLE_MIN)
821 return NULL;
822
823 if (n > RT_TABLE_MAX)
824 return NULL;
825
826 h = n & (DN_FIB_TABLE_HASHSZ - 1);
827 rcu_read_lock();
828 hlist_for_each_entry_rcu(t, node, &dn_fib_table_hash[h], hlist) {
829 if (t->n == n) {
830 rcu_read_unlock();
831 return t;
832 }
833 }
834 rcu_read_unlock();
835
836 if (!create)
837 return NULL;
838
839 if (in_interrupt() && net_ratelimit()) {
840 printk(KERN_DEBUG "DECnet: BUG! Attempt to create routing table from interrupt\n");
841 return NULL;
842 }
843
844 t = kzalloc(sizeof(struct dn_fib_table) + sizeof(struct dn_hash),
845 GFP_KERNEL);
846 if (t == NULL)
847 return NULL;
848
849 t->n = n;
850 t->insert = dn_fib_table_insert;
851 t->delete = dn_fib_table_delete;
852 t->lookup = dn_fib_table_lookup;
853 t->flush = dn_fib_table_flush;
854 t->dump = dn_fib_table_dump;
855 hlist_add_head_rcu(&t->hlist, &dn_fib_table_hash[h]);
856
857 return t;
858 }
859
dn_fib_empty_table(void)860 struct dn_fib_table *dn_fib_empty_table(void)
861 {
862 u32 id;
863
864 for(id = RT_TABLE_MIN; id <= RT_TABLE_MAX; id++)
865 if (dn_fib_get_table(id, 0) == NULL)
866 return dn_fib_get_table(id, 1);
867 return NULL;
868 }
869
dn_fib_flush(void)870 void dn_fib_flush(void)
871 {
872 int flushed = 0;
873 struct dn_fib_table *tb;
874 struct hlist_node *node;
875 unsigned int h;
876
877 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
878 hlist_for_each_entry(tb, node, &dn_fib_table_hash[h], hlist)
879 flushed += tb->flush(tb);
880 }
881
882 if (flushed)
883 dn_rt_cache_flush(-1);
884 }
885
dn_fib_table_init(void)886 void __init dn_fib_table_init(void)
887 {
888 dn_hash_kmem = kmem_cache_create("dn_fib_info_cache",
889 sizeof(struct dn_fib_info),
890 0, SLAB_HWCACHE_ALIGN,
891 NULL);
892 }
893
dn_fib_table_cleanup(void)894 void __exit dn_fib_table_cleanup(void)
895 {
896 struct dn_fib_table *t;
897 struct hlist_node *node, *next;
898 unsigned int h;
899
900 write_lock(&dn_fib_tables_lock);
901 for (h = 0; h < DN_FIB_TABLE_HASHSZ; h++) {
902 hlist_for_each_entry_safe(t, node, next, &dn_fib_table_hash[h],
903 hlist) {
904 hlist_del(&t->hlist);
905 kfree(t);
906 }
907 }
908 write_unlock(&dn_fib_tables_lock);
909 }
910