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/string.h>
21 #include <linux/net.h>
22 #include <linux/socket.h>
23 #include <linux/slab.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>
38 #include <net/fib_rules.h>
40 #include <net/dn_route.h>
41 #include <net/dn_fib.h>
42 #include <net/dn_neigh.h>
43 #include <net/dn_dev.h>
45 #define RT_MIN_TABLE 1
47 #define for_fib_info() { struct dn_fib_info *fi;\
48 for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
49 #define endfor_fib_info() }
51 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
52 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
54 #define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
55 for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
57 #define endfor_nexthops(fi) }
59 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
60 static struct dn_fib_info *dn_fib_info_list;
61 static DEFINE_SPINLOCK(dn_fib_info_lock);
67 } dn_fib_props[RTN_MAX+1] = {
68 [RTN_UNSPEC] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
69 [RTN_UNICAST] = { .error = 0, .scope = RT_SCOPE_UNIVERSE },
70 [RTN_LOCAL] = { .error = 0, .scope = RT_SCOPE_HOST },
71 [RTN_BROADCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
72 [RTN_ANYCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
73 [RTN_MULTICAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
74 [RTN_BLACKHOLE] = { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
75 [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
76 [RTN_PROHIBIT] = { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
77 [RTN_THROW] = { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
78 [RTN_NAT] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
79 [RTN_XRESOLVE] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
82 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
83 static int dn_fib_sync_up(struct net_device *dev);
85 void dn_fib_free_info(struct dn_fib_info *fi)
87 if (fi->fib_dead == 0) {
88 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
96 } endfor_nexthops(fi);
100 void dn_fib_release_info(struct dn_fib_info *fi)
102 spin_lock(&dn_fib_info_lock);
103 if (fi && --fi->fib_treeref == 0) {
105 fi->fib_next->fib_prev = fi->fib_prev;
107 fi->fib_prev->fib_next = fi->fib_next;
108 if (fi == dn_fib_info_list)
109 dn_fib_info_list = fi->fib_next;
113 spin_unlock(&dn_fib_info_lock);
116 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
118 const struct dn_fib_nh *onh = ofi->fib_nh;
121 if (nh->nh_oif != onh->nh_oif ||
122 nh->nh_gw != onh->nh_gw ||
123 nh->nh_scope != onh->nh_scope ||
124 nh->nh_weight != onh->nh_weight ||
125 ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
128 } endfor_nexthops(fi);
132 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
135 if (fi->fib_nhs != nfi->fib_nhs)
137 if (nfi->fib_protocol == fi->fib_protocol &&
138 nfi->fib_prefsrc == fi->fib_prefsrc &&
139 nfi->fib_priority == fi->fib_priority &&
140 memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
141 ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
142 (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
148 __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
150 while(RTA_OK(attr,attrlen)) {
151 if (attr->rta_type == type)
152 return *(__le16*)RTA_DATA(attr);
153 attr = RTA_NEXT(attr, attrlen);
159 static int dn_fib_count_nhs(struct rtattr *rta)
162 struct rtnexthop *nhp = RTA_DATA(rta);
163 int nhlen = RTA_PAYLOAD(rta);
165 while(nhlen >= (int)sizeof(struct rtnexthop)) {
166 if ((nhlen -= nhp->rtnh_len) < 0)
169 nhp = RTNH_NEXT(nhp);
175 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
177 struct rtnexthop *nhp = RTA_DATA(rta);
178 int nhlen = RTA_PAYLOAD(rta);
180 change_nexthops(fi) {
181 int attrlen = nhlen - sizeof(struct rtnexthop);
182 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
185 nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
186 nh->nh_oif = nhp->rtnh_ifindex;
187 nh->nh_weight = nhp->rtnh_hops + 1;
190 nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
192 nhp = RTNH_NEXT(nhp);
193 } endfor_nexthops(fi);
199 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
205 struct dn_fib_res res;
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(&init_net, 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(&init_net, 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 (r->rtm_type > RTN_MAX)
281 if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
285 nhs = dn_fib_count_nhs(rta->rta_mp);
290 fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
295 fi->fib_protocol = r->rtm_protocol;
297 fi->fib_flags = r->rtm_flags;
298 if (rta->rta_priority)
299 fi->fib_priority = *rta->rta_priority;
301 int attrlen = RTA_PAYLOAD(rta->rta_mx);
302 struct rtattr *attr = RTA_DATA(rta->rta_mx);
304 while(RTA_OK(attr, attrlen)) {
305 unsigned flavour = attr->rta_type;
307 if (flavour > RTAX_MAX)
309 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
311 attr = RTA_NEXT(attr, attrlen);
314 if (rta->rta_prefsrc)
315 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
318 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
320 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
322 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
325 struct dn_fib_nh *nh = fi->fib_nh;
327 nh->nh_oif = *rta->rta_oif;
329 memcpy(&nh->nh_gw, rta->rta_gw, 2);
330 nh->nh_flags = r->rtm_flags;
334 if (r->rtm_type == RTN_NAT) {
335 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
337 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
341 if (dn_fib_props[r->rtm_type].error) {
342 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
347 if (r->rtm_scope > RT_SCOPE_HOST)
350 if (r->rtm_scope == RT_SCOPE_HOST) {
351 struct dn_fib_nh *nh = fi->fib_nh;
353 /* Local address is added */
354 if (nhs != 1 || nh->nh_gw)
356 nh->nh_scope = RT_SCOPE_NOWHERE;
357 nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
359 if (nh->nh_dev == NULL)
362 change_nexthops(fi) {
363 if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
365 } endfor_nexthops(fi)
368 if (fi->fib_prefsrc) {
369 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
370 memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
371 if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
376 if ((ofi = dn_fib_find_info(fi)) != NULL) {
378 dn_fib_free_info(fi);
384 atomic_inc(&fi->fib_clntref);
385 spin_lock(&dn_fib_info_lock);
386 fi->fib_next = dn_fib_info_list;
388 if (dn_fib_info_list)
389 dn_fib_info_list->fib_prev = fi;
390 dn_fib_info_list = fi;
391 spin_unlock(&dn_fib_info_lock);
401 dn_fib_free_info(fi);
407 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
409 int err = dn_fib_props[type].error;
412 if (fi->fib_flags & RTNH_F_DEAD)
419 DN_FIB_RES_RESET(*res);
420 atomic_inc(&fi->fib_clntref);
425 if (nh->nh_flags & RTNH_F_DEAD)
427 if (!fl->oif || fl->oif == nh->nh_oif)
430 if (nhsel < fi->fib_nhs) {
432 atomic_inc(&fi->fib_clntref);
440 printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
448 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
450 struct dn_fib_info *fi = res->fi;
453 spin_lock_bh(&dn_fib_multipath_lock);
454 if (fi->fib_power <= 0) {
456 change_nexthops(fi) {
457 if (!(nh->nh_flags&RTNH_F_DEAD)) {
458 power += nh->nh_weight;
459 nh->nh_power = nh->nh_weight;
461 } endfor_nexthops(fi);
462 fi->fib_power = power;
464 spin_unlock_bh(&dn_fib_multipath_lock);
470 w = jiffies % fi->fib_power;
472 change_nexthops(fi) {
473 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
474 if ((w -= nh->nh_power) <= 0) {
478 spin_unlock_bh(&dn_fib_multipath_lock);
482 } endfor_nexthops(fi);
484 spin_unlock_bh(&dn_fib_multipath_lock);
488 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
492 for(i = 1; i <= RTA_MAX; i++) {
493 struct rtattr *attr = rta[i-1];
495 if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
497 if (i != RTA_MULTIPATH && i != RTA_METRICS &&
499 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
506 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
508 struct net *net = sock_net(skb->sk);
509 struct dn_fib_table *tb;
510 struct rtattr **rta = arg;
511 struct rtmsg *r = NLMSG_DATA(nlh);
513 if (!net_eq(net, &init_net))
516 if (dn_fib_check_attr(r, rta))
519 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
521 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
526 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
528 struct net *net = sock_net(skb->sk);
529 struct dn_fib_table *tb;
530 struct rtattr **rta = arg;
531 struct rtmsg *r = NLMSG_DATA(nlh);
533 if (!net_eq(net, &init_net))
536 if (dn_fib_check_attr(r, rta))
539 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
541 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
546 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
548 struct dn_fib_table *tb;
553 struct dn_kern_rta rta;
555 memset(&req.rtm, 0, sizeof(req.rtm));
556 memset(&rta, 0, sizeof(rta));
558 if (type == RTN_UNICAST)
559 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
561 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
566 req.nlh.nlmsg_len = sizeof(req);
567 req.nlh.nlmsg_type = cmd;
568 req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
569 req.nlh.nlmsg_pid = 0;
570 req.nlh.nlmsg_seq = 0;
572 req.rtm.rtm_dst_len = dst_len;
573 req.rtm.rtm_table = tb->n;
574 req.rtm.rtm_protocol = RTPROT_KERNEL;
575 req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
576 req.rtm.rtm_type = type;
579 rta.rta_prefsrc = &ifa->ifa_local;
580 rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
582 if (cmd == RTM_NEWROUTE)
583 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
585 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
588 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
591 fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
594 if (!(dev->flags&IFF_UP))
596 /* In the future, we will want to add default routes here */
601 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
604 struct net_device *dev;
605 struct dn_dev *dn_db;
606 struct dn_ifaddr *ifa2;
610 /* Scan device list */
612 for_each_netdev_rcu(&init_net, dev) {
613 dn_db = rcu_dereference(dev->dn_ptr);
616 for (ifa2 = rcu_dereference(dn_db->ifa_list);
618 ifa2 = rcu_dereference(ifa2->ifa_next)) {
619 if (ifa2->ifa_local == ifa->ifa_local) {
628 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
630 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
631 if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
637 static void dn_fib_disable_addr(struct net_device *dev, int force)
639 if (dn_fib_sync_down(0, dev, force))
641 dn_rt_cache_flush(0);
642 neigh_ifdown(&dn_neigh_table, dev);
645 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
647 struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
651 dn_fib_add_ifaddr(ifa);
652 dn_fib_sync_up(ifa->ifa_dev->dev);
653 dn_rt_cache_flush(-1);
656 dn_fib_del_ifaddr(ifa);
657 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
658 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
660 dn_rt_cache_flush(-1);
667 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
670 int scope = RT_SCOPE_NOWHERE;
677 * This makes no sense for DECnet.... we will almost
678 * certainly have more than one local address the same
679 * over all our interfaces. It needs thinking about
682 if (local && fi->fib_prefsrc == local) {
683 fi->fib_flags |= RTNH_F_DEAD;
685 } else if (dev && fi->fib_nhs) {
688 change_nexthops(fi) {
689 if (nh->nh_flags&RTNH_F_DEAD)
691 else if (nh->nh_dev == dev &&
692 nh->nh_scope != scope) {
693 spin_lock_bh(&dn_fib_multipath_lock);
694 nh->nh_flags |= RTNH_F_DEAD;
695 fi->fib_power -= nh->nh_power;
697 spin_unlock_bh(&dn_fib_multipath_lock);
700 } endfor_nexthops(fi)
701 if (dead == fi->fib_nhs) {
702 fi->fib_flags |= RTNH_F_DEAD;
711 static int dn_fib_sync_up(struct net_device *dev)
715 if (!(dev->flags&IFF_UP))
721 change_nexthops(fi) {
722 if (!(nh->nh_flags&RTNH_F_DEAD)) {
726 if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
728 if (nh->nh_dev != dev || dev->dn_ptr == NULL)
731 spin_lock_bh(&dn_fib_multipath_lock);
733 nh->nh_flags &= ~RTNH_F_DEAD;
734 spin_unlock_bh(&dn_fib_multipath_lock);
735 } endfor_nexthops(fi);
738 fi->fib_flags &= ~RTNH_F_DEAD;
745 static struct notifier_block dn_fib_dnaddr_notifier = {
746 .notifier_call = dn_fib_dnaddr_event,
749 void __exit dn_fib_cleanup(void)
751 dn_fib_table_cleanup();
752 dn_fib_rules_cleanup();
754 unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
758 void __init dn_fib_init(void)
763 register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
765 rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL);
766 rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL);