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.
6 * DECnet Routing Forwarding Information Base (Glue/Info List)
8 * Author: Steve Whitehouse <SteveW@ACM.org>
12 * Alexey Kuznetsov : SMP locking changes
13 * Steve Whitehouse : Rewrote it... Well to be more correct, I
14 * copied most of it from the ipv4 fib code.
15 * Steve Whitehouse : Updated it in style and fixed a few bugs
16 * which were fixed in the ipv4 code since
17 * this code was copied from it.
20 #include <linux/config.h>
21 #include <linux/string.h>
22 #include <linux/net.h>
23 #include <linux/socket.h>
24 #include <linux/sockios.h>
25 #include <linux/init.h>
26 #include <linux/skbuff.h>
27 #include <linux/netlink.h>
28 #include <linux/rtnetlink.h>
29 #include <linux/proc_fs.h>
30 #include <linux/netdevice.h>
31 #include <linux/timer.h>
32 #include <linux/spinlock.h>
33 #include <asm/atomic.h>
34 #include <asm/uaccess.h>
35 #include <net/neighbour.h>
39 #include <net/dn_route.h>
40 #include <net/dn_fib.h>
41 #include <net/dn_neigh.h>
42 #include <net/dn_dev.h>
44 #define RT_MIN_TABLE 1
46 #define for_fib_info() { struct dn_fib_info *fi;\
47 for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
48 #define endfor_fib_info() }
50 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
51 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
53 #define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
54 for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
56 #define endfor_nexthops(fi) }
58 extern int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb);
60 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
61 static struct dn_fib_info *dn_fib_info_list;
62 static DEFINE_RWLOCK(dn_fib_info_lock);
68 } dn_fib_props[RTA_MAX+1] = {
69 [RTN_UNSPEC] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
70 [RTN_UNICAST] = { .error = 0, .scope = RT_SCOPE_UNIVERSE },
71 [RTN_LOCAL] = { .error = 0, .scope = RT_SCOPE_HOST },
72 [RTN_BROADCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
73 [RTN_ANYCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
74 [RTN_MULTICAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
75 [RTN_BLACKHOLE] = { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
76 [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
77 [RTN_PROHIBIT] = { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
78 [RTN_THROW] = { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
79 [RTN_NAT] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
80 [RTN_XRESOLVE] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
83 void dn_fib_free_info(struct dn_fib_info *fi)
85 if (fi->fib_dead == 0) {
86 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
94 } endfor_nexthops(fi);
98 void dn_fib_release_info(struct dn_fib_info *fi)
100 write_lock(&dn_fib_info_lock);
101 if (fi && --fi->fib_treeref == 0) {
103 fi->fib_next->fib_prev = fi->fib_prev;
105 fi->fib_prev->fib_next = fi->fib_next;
106 if (fi == dn_fib_info_list)
107 dn_fib_info_list = fi->fib_next;
111 write_unlock(&dn_fib_info_lock);
114 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
116 const struct dn_fib_nh *onh = ofi->fib_nh;
119 if (nh->nh_oif != onh->nh_oif ||
120 nh->nh_gw != onh->nh_gw ||
121 nh->nh_scope != onh->nh_scope ||
122 nh->nh_weight != onh->nh_weight ||
123 ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
126 } endfor_nexthops(fi);
130 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
133 if (fi->fib_nhs != nfi->fib_nhs)
135 if (nfi->fib_protocol == fi->fib_protocol &&
136 nfi->fib_prefsrc == fi->fib_prefsrc &&
137 nfi->fib_priority == fi->fib_priority &&
138 memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
139 ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
140 (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
146 u16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
148 while(RTA_OK(attr,attrlen)) {
149 if (attr->rta_type == type)
150 return *(u16*)RTA_DATA(attr);
151 attr = RTA_NEXT(attr, attrlen);
157 static int dn_fib_count_nhs(struct rtattr *rta)
160 struct rtnexthop *nhp = RTA_DATA(rta);
161 int nhlen = RTA_PAYLOAD(rta);
163 while(nhlen >= (int)sizeof(struct rtnexthop)) {
164 if ((nhlen -= nhp->rtnh_len) < 0)
167 nhp = RTNH_NEXT(nhp);
173 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
175 struct rtnexthop *nhp = RTA_DATA(rta);
176 int nhlen = RTA_PAYLOAD(rta);
178 change_nexthops(fi) {
179 int attrlen = nhlen - sizeof(struct rtnexthop);
180 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
183 nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
184 nh->nh_oif = nhp->rtnh_ifindex;
185 nh->nh_weight = nhp->rtnh_hops + 1;
188 nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
190 nhp = RTNH_NEXT(nhp);
191 } endfor_nexthops(fi);
197 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
203 struct dn_fib_res res;
205 memset(&fl, 0, sizeof(fl));
207 if (nh->nh_flags&RTNH_F_ONLINK) {
208 struct net_device *dev;
210 if (r->rtm_scope >= RT_SCOPE_LINK)
212 if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
214 if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
216 if (!(dev->flags&IFF_UP))
220 nh->nh_scope = RT_SCOPE_LINK;
224 memset(&fl, 0, sizeof(fl));
225 fl.fld_dst = nh->nh_gw;
227 fl.fld_scope = r->rtm_scope + 1;
229 if (fl.fld_scope < RT_SCOPE_LINK)
230 fl.fld_scope = RT_SCOPE_LINK;
232 if ((err = dn_fib_lookup(&fl, &res)) != 0)
236 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
238 nh->nh_scope = res.scope;
239 nh->nh_oif = DN_FIB_RES_OIF(res);
240 nh->nh_dev = DN_FIB_RES_DEV(res);
241 if (nh->nh_dev == NULL)
243 dev_hold(nh->nh_dev);
245 if (!(nh->nh_dev->flags & IFF_UP))
249 dn_fib_res_put(&res);
252 struct net_device *dev;
254 if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
257 dev = __dev_get_by_index(nh->nh_oif);
258 if (dev == NULL || dev->dn_ptr == NULL)
260 if (!(dev->flags&IFF_UP))
263 dev_hold(nh->nh_dev);
264 nh->nh_scope = RT_SCOPE_HOST;
271 struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
274 struct dn_fib_info *fi = NULL;
275 struct dn_fib_info *ofi;
278 if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
282 nhs = dn_fib_count_nhs(rta->rta_mp);
287 fi = kmalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
291 memset(fi, 0, sizeof(*fi)+nhs*sizeof(struct dn_fib_nh));
293 fi->fib_protocol = r->rtm_protocol;
295 fi->fib_flags = r->rtm_flags;
296 if (rta->rta_priority)
297 fi->fib_priority = *rta->rta_priority;
299 int attrlen = RTA_PAYLOAD(rta->rta_mx);
300 struct rtattr *attr = RTA_DATA(rta->rta_mx);
302 while(RTA_OK(attr, attrlen)) {
303 unsigned flavour = attr->rta_type;
305 if (flavour > RTAX_MAX)
307 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
309 attr = RTA_NEXT(attr, attrlen);
312 if (rta->rta_prefsrc)
313 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
316 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
318 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
320 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
323 struct dn_fib_nh *nh = fi->fib_nh;
325 nh->nh_oif = *rta->rta_oif;
327 memcpy(&nh->nh_gw, rta->rta_gw, 2);
328 nh->nh_flags = r->rtm_flags;
332 if (r->rtm_type == RTN_NAT) {
333 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
335 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
339 if (dn_fib_props[r->rtm_type].error) {
340 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
345 if (r->rtm_scope > RT_SCOPE_HOST)
348 if (r->rtm_scope == RT_SCOPE_HOST) {
349 struct dn_fib_nh *nh = fi->fib_nh;
351 /* Local address is added */
352 if (nhs != 1 || nh->nh_gw)
354 nh->nh_scope = RT_SCOPE_NOWHERE;
355 nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
357 if (nh->nh_dev == NULL)
360 change_nexthops(fi) {
361 if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
363 } endfor_nexthops(fi)
366 if (fi->fib_prefsrc) {
367 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
368 memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
369 if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
374 if ((ofi = dn_fib_find_info(fi)) != NULL) {
376 dn_fib_free_info(fi);
382 atomic_inc(&fi->fib_clntref);
383 write_lock(&dn_fib_info_lock);
384 fi->fib_next = dn_fib_info_list;
386 if (dn_fib_info_list)
387 dn_fib_info_list->fib_prev = fi;
388 dn_fib_info_list = fi;
389 write_unlock(&dn_fib_info_lock);
399 dn_fib_free_info(fi);
405 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
407 int err = dn_fib_props[type].error;
410 if (fi->fib_flags & RTNH_F_DEAD)
417 DN_FIB_RES_RESET(*res);
418 atomic_inc(&fi->fib_clntref);
423 if (nh->nh_flags & RTNH_F_DEAD)
425 if (!fl->oif || fl->oif == nh->nh_oif)
428 if (nhsel < fi->fib_nhs) {
430 atomic_inc(&fi->fib_clntref);
438 printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
446 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
448 struct dn_fib_info *fi = res->fi;
451 spin_lock_bh(&dn_fib_multipath_lock);
452 if (fi->fib_power <= 0) {
454 change_nexthops(fi) {
455 if (!(nh->nh_flags&RTNH_F_DEAD)) {
456 power += nh->nh_weight;
457 nh->nh_power = nh->nh_weight;
459 } endfor_nexthops(fi);
460 fi->fib_power = power;
462 spin_unlock_bh(&dn_fib_multipath_lock);
468 w = jiffies % fi->fib_power;
470 change_nexthops(fi) {
471 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
472 if ((w -= nh->nh_power) <= 0) {
476 spin_unlock_bh(&dn_fib_multipath_lock);
480 } endfor_nexthops(fi);
482 spin_unlock_bh(&dn_fib_multipath_lock);
486 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
490 for(i = 1; i <= RTA_MAX; i++) {
491 struct rtattr *attr = rta[i-1];
493 if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
495 if (i != RTA_MULTIPATH && i != RTA_METRICS)
496 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
503 int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
505 struct dn_fib_table *tb;
506 struct rtattr **rta = arg;
507 struct rtmsg *r = NLMSG_DATA(nlh);
509 if (dn_fib_check_attr(r, rta))
512 tb = dn_fib_get_table(r->rtm_table, 0);
514 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
519 int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
521 struct dn_fib_table *tb;
522 struct rtattr **rta = arg;
523 struct rtmsg *r = NLMSG_DATA(nlh);
525 if (dn_fib_check_attr(r, rta))
528 tb = dn_fib_get_table(r->rtm_table, 1);
530 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
536 int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
540 struct dn_fib_table *tb;
542 if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) &&
543 ((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED)
544 return dn_cache_dump(skb, cb);
548 s_t = cb->args[0] = RT_MIN_TABLE;
550 for(t = s_t; t <= RT_TABLE_MAX; t++) {
554 memset(&cb->args[1], 0,
555 sizeof(cb->args) - sizeof(cb->args[0]));
556 tb = dn_fib_get_table(t, 0);
559 if (tb->dump(tb, skb, cb) < 0)
568 static void fib_magic(int cmd, int type, __u16 dst, int dst_len, struct dn_ifaddr *ifa)
570 struct dn_fib_table *tb;
575 struct dn_kern_rta rta;
577 memset(&req.rtm, 0, sizeof(req.rtm));
578 memset(&rta, 0, sizeof(rta));
580 if (type == RTN_UNICAST)
581 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
583 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
588 req.nlh.nlmsg_len = sizeof(req);
589 req.nlh.nlmsg_type = cmd;
590 req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
591 req.nlh.nlmsg_pid = 0;
592 req.nlh.nlmsg_seq = 0;
594 req.rtm.rtm_dst_len = dst_len;
595 req.rtm.rtm_table = tb->n;
596 req.rtm.rtm_protocol = RTPROT_KERNEL;
597 req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
598 req.rtm.rtm_type = type;
601 rta.rta_prefsrc = &ifa->ifa_local;
602 rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
604 if (cmd == RTM_NEWROUTE)
605 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
607 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
610 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
613 fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
616 if (!(dev->flags&IFF_UP))
618 /* In the future, we will want to add default routes here */
623 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
626 struct net_device *dev;
627 struct dn_dev *dn_db;
628 struct dn_ifaddr *ifa2;
632 /* Scan device list */
633 read_lock(&dev_base_lock);
634 for(dev = dev_base; dev; dev = dev->next) {
638 for(ifa2 = dn_db->ifa_list; ifa2; ifa2 = ifa2->ifa_next) {
639 if (ifa2->ifa_local == ifa->ifa_local) {
645 read_unlock(&dev_base_lock);
648 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
650 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
651 if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
657 static void dn_fib_disable_addr(struct net_device *dev, int force)
659 if (dn_fib_sync_down(0, dev, force))
661 dn_rt_cache_flush(0);
662 neigh_ifdown(&dn_neigh_table, dev);
665 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
667 struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
671 dn_fib_add_ifaddr(ifa);
672 dn_fib_sync_up(ifa->ifa_dev->dev);
673 dn_rt_cache_flush(-1);
676 dn_fib_del_ifaddr(ifa);
677 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
678 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
680 dn_rt_cache_flush(-1);
687 int dn_fib_sync_down(dn_address local, struct net_device *dev, int force)
690 int scope = RT_SCOPE_NOWHERE;
697 * This makes no sense for DECnet.... we will almost
698 * certainly have more than one local address the same
699 * over all our interfaces. It needs thinking about
702 if (local && fi->fib_prefsrc == local) {
703 fi->fib_flags |= RTNH_F_DEAD;
705 } else if (dev && fi->fib_nhs) {
708 change_nexthops(fi) {
709 if (nh->nh_flags&RTNH_F_DEAD)
711 else if (nh->nh_dev == dev &&
712 nh->nh_scope != scope) {
713 spin_lock_bh(&dn_fib_multipath_lock);
714 nh->nh_flags |= RTNH_F_DEAD;
715 fi->fib_power -= nh->nh_power;
717 spin_unlock_bh(&dn_fib_multipath_lock);
720 } endfor_nexthops(fi)
721 if (dead == fi->fib_nhs) {
722 fi->fib_flags |= RTNH_F_DEAD;
731 int dn_fib_sync_up(struct net_device *dev)
735 if (!(dev->flags&IFF_UP))
741 change_nexthops(fi) {
742 if (!(nh->nh_flags&RTNH_F_DEAD)) {
746 if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
748 if (nh->nh_dev != dev || dev->dn_ptr == NULL)
751 spin_lock_bh(&dn_fib_multipath_lock);
753 nh->nh_flags &= ~RTNH_F_DEAD;
754 spin_unlock_bh(&dn_fib_multipath_lock);
755 } endfor_nexthops(fi);
758 fi->fib_flags &= ~RTNH_F_DEAD;
765 void dn_fib_flush(void)
768 struct dn_fib_table *tb;
771 for(id = RT_TABLE_MAX; id > 0; id--) {
772 if ((tb = dn_fib_get_table(id, 0)) == NULL)
774 flushed += tb->flush(tb);
778 dn_rt_cache_flush(-1);
781 static struct notifier_block dn_fib_dnaddr_notifier = {
782 .notifier_call = dn_fib_dnaddr_event,
785 void __exit dn_fib_cleanup(void)
787 dn_fib_table_cleanup();
788 dn_fib_rules_cleanup();
790 unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
794 void __init dn_fib_init(void)
800 register_dnaddr_notifier(&dn_fib_dnaddr_notifier);