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/sockios.h>
24 #include <linux/init.h>
25 #include <linux/skbuff.h>
26 #include <linux/netlink.h>
27 #include <linux/rtnetlink.h>
28 #include <linux/proc_fs.h>
29 #include <linux/netdevice.h>
30 #include <linux/timer.h>
31 #include <linux/spinlock.h>
32 #include <asm/atomic.h>
33 #include <asm/uaccess.h>
34 #include <net/neighbour.h>
38 #include <net/dn_route.h>
39 #include <net/dn_fib.h>
40 #include <net/dn_neigh.h>
41 #include <net/dn_dev.h>
43 #define RT_MIN_TABLE 1
45 #define for_fib_info() { struct dn_fib_info *fi;\
46 for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
47 #define endfor_fib_info() }
49 #define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
50 for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
52 #define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
53 for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
55 #define endfor_nexthops(fi) }
57 extern int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb);
59 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
60 static struct dn_fib_info *dn_fib_info_list;
61 static DEFINE_RWLOCK(dn_fib_info_lock);
67 } dn_fib_props[RTA_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 void dn_fib_free_info(struct dn_fib_info *fi)
84 if (fi->fib_dead == 0) {
85 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
93 } endfor_nexthops(fi);
97 void dn_fib_release_info(struct dn_fib_info *fi)
99 write_lock(&dn_fib_info_lock);
100 if (fi && --fi->fib_treeref == 0) {
102 fi->fib_next->fib_prev = fi->fib_prev;
104 fi->fib_prev->fib_next = fi->fib_next;
105 if (fi == dn_fib_info_list)
106 dn_fib_info_list = fi->fib_next;
110 write_unlock(&dn_fib_info_lock);
113 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
115 const struct dn_fib_nh *onh = ofi->fib_nh;
118 if (nh->nh_oif != onh->nh_oif ||
119 nh->nh_gw != onh->nh_gw ||
120 nh->nh_scope != onh->nh_scope ||
121 nh->nh_weight != onh->nh_weight ||
122 ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
125 } endfor_nexthops(fi);
129 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
132 if (fi->fib_nhs != nfi->fib_nhs)
134 if (nfi->fib_protocol == fi->fib_protocol &&
135 nfi->fib_prefsrc == fi->fib_prefsrc &&
136 nfi->fib_priority == fi->fib_priority &&
137 memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
138 ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
139 (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
145 __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
147 while(RTA_OK(attr,attrlen)) {
148 if (attr->rta_type == type)
149 return *(__le16*)RTA_DATA(attr);
150 attr = RTA_NEXT(attr, attrlen);
156 static int dn_fib_count_nhs(struct rtattr *rta)
159 struct rtnexthop *nhp = RTA_DATA(rta);
160 int nhlen = RTA_PAYLOAD(rta);
162 while(nhlen >= (int)sizeof(struct rtnexthop)) {
163 if ((nhlen -= nhp->rtnh_len) < 0)
166 nhp = RTNH_NEXT(nhp);
172 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
174 struct rtnexthop *nhp = RTA_DATA(rta);
175 int nhlen = RTA_PAYLOAD(rta);
177 change_nexthops(fi) {
178 int attrlen = nhlen - sizeof(struct rtnexthop);
179 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
182 nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
183 nh->nh_oif = nhp->rtnh_ifindex;
184 nh->nh_weight = nhp->rtnh_hops + 1;
187 nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
189 nhp = RTNH_NEXT(nhp);
190 } endfor_nexthops(fi);
196 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
202 struct dn_fib_res res;
204 memset(&fl, 0, sizeof(fl));
206 if (nh->nh_flags&RTNH_F_ONLINK) {
207 struct net_device *dev;
209 if (r->rtm_scope >= RT_SCOPE_LINK)
211 if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
213 if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
215 if (!(dev->flags&IFF_UP))
219 nh->nh_scope = RT_SCOPE_LINK;
223 memset(&fl, 0, sizeof(fl));
224 fl.fld_dst = nh->nh_gw;
226 fl.fld_scope = r->rtm_scope + 1;
228 if (fl.fld_scope < RT_SCOPE_LINK)
229 fl.fld_scope = RT_SCOPE_LINK;
231 if ((err = dn_fib_lookup(&fl, &res)) != 0)
235 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
237 nh->nh_scope = res.scope;
238 nh->nh_oif = DN_FIB_RES_OIF(res);
239 nh->nh_dev = DN_FIB_RES_DEV(res);
240 if (nh->nh_dev == NULL)
242 dev_hold(nh->nh_dev);
244 if (!(nh->nh_dev->flags & IFF_UP))
248 dn_fib_res_put(&res);
251 struct net_device *dev;
253 if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
256 dev = __dev_get_by_index(nh->nh_oif);
257 if (dev == NULL || dev->dn_ptr == NULL)
259 if (!(dev->flags&IFF_UP))
262 dev_hold(nh->nh_dev);
263 nh->nh_scope = RT_SCOPE_HOST;
270 struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
273 struct dn_fib_info *fi = NULL;
274 struct dn_fib_info *ofi;
277 if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
281 nhs = dn_fib_count_nhs(rta->rta_mp);
286 fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
291 fi->fib_protocol = r->rtm_protocol;
293 fi->fib_flags = r->rtm_flags;
294 if (rta->rta_priority)
295 fi->fib_priority = *rta->rta_priority;
297 int attrlen = RTA_PAYLOAD(rta->rta_mx);
298 struct rtattr *attr = RTA_DATA(rta->rta_mx);
300 while(RTA_OK(attr, attrlen)) {
301 unsigned flavour = attr->rta_type;
303 if (flavour > RTAX_MAX)
305 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
307 attr = RTA_NEXT(attr, attrlen);
310 if (rta->rta_prefsrc)
311 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
314 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
316 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
318 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
321 struct dn_fib_nh *nh = fi->fib_nh;
323 nh->nh_oif = *rta->rta_oif;
325 memcpy(&nh->nh_gw, rta->rta_gw, 2);
326 nh->nh_flags = r->rtm_flags;
330 if (r->rtm_type == RTN_NAT) {
331 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
333 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
337 if (dn_fib_props[r->rtm_type].error) {
338 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
343 if (r->rtm_scope > RT_SCOPE_HOST)
346 if (r->rtm_scope == RT_SCOPE_HOST) {
347 struct dn_fib_nh *nh = fi->fib_nh;
349 /* Local address is added */
350 if (nhs != 1 || nh->nh_gw)
352 nh->nh_scope = RT_SCOPE_NOWHERE;
353 nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
355 if (nh->nh_dev == NULL)
358 change_nexthops(fi) {
359 if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
361 } endfor_nexthops(fi)
364 if (fi->fib_prefsrc) {
365 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
366 memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
367 if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
372 if ((ofi = dn_fib_find_info(fi)) != NULL) {
374 dn_fib_free_info(fi);
380 atomic_inc(&fi->fib_clntref);
381 write_lock(&dn_fib_info_lock);
382 fi->fib_next = dn_fib_info_list;
384 if (dn_fib_info_list)
385 dn_fib_info_list->fib_prev = fi;
386 dn_fib_info_list = fi;
387 write_unlock(&dn_fib_info_lock);
397 dn_fib_free_info(fi);
403 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
405 int err = dn_fib_props[type].error;
408 if (fi->fib_flags & RTNH_F_DEAD)
415 DN_FIB_RES_RESET(*res);
416 atomic_inc(&fi->fib_clntref);
421 if (nh->nh_flags & RTNH_F_DEAD)
423 if (!fl->oif || fl->oif == nh->nh_oif)
426 if (nhsel < fi->fib_nhs) {
428 atomic_inc(&fi->fib_clntref);
436 printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
444 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
446 struct dn_fib_info *fi = res->fi;
449 spin_lock_bh(&dn_fib_multipath_lock);
450 if (fi->fib_power <= 0) {
452 change_nexthops(fi) {
453 if (!(nh->nh_flags&RTNH_F_DEAD)) {
454 power += nh->nh_weight;
455 nh->nh_power = nh->nh_weight;
457 } endfor_nexthops(fi);
458 fi->fib_power = power;
460 spin_unlock_bh(&dn_fib_multipath_lock);
466 w = jiffies % fi->fib_power;
468 change_nexthops(fi) {
469 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
470 if ((w -= nh->nh_power) <= 0) {
474 spin_unlock_bh(&dn_fib_multipath_lock);
478 } endfor_nexthops(fi);
480 spin_unlock_bh(&dn_fib_multipath_lock);
484 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
488 for(i = 1; i <= RTA_MAX; i++) {
489 struct rtattr *attr = rta[i-1];
491 if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
493 if (i != RTA_MULTIPATH && i != RTA_METRICS)
494 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
501 int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
503 struct dn_fib_table *tb;
504 struct rtattr **rta = arg;
505 struct rtmsg *r = NLMSG_DATA(nlh);
507 if (dn_fib_check_attr(r, rta))
510 tb = dn_fib_get_table(r->rtm_table, 0);
512 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
517 int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
519 struct dn_fib_table *tb;
520 struct rtattr **rta = arg;
521 struct rtmsg *r = NLMSG_DATA(nlh);
523 if (dn_fib_check_attr(r, rta))
526 tb = dn_fib_get_table(r->rtm_table, 1);
528 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
534 int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
538 struct dn_fib_table *tb;
540 if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) &&
541 ((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED)
542 return dn_cache_dump(skb, cb);
546 s_t = cb->args[0] = RT_MIN_TABLE;
548 for(t = s_t; t <= RT_TABLE_MAX; t++) {
552 memset(&cb->args[1], 0,
553 sizeof(cb->args) - sizeof(cb->args[0]));
554 tb = dn_fib_get_table(t, 0);
557 if (tb->dump(tb, skb, cb) < 0)
566 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
568 struct dn_fib_table *tb;
573 struct dn_kern_rta rta;
575 memset(&req.rtm, 0, sizeof(req.rtm));
576 memset(&rta, 0, sizeof(rta));
578 if (type == RTN_UNICAST)
579 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
581 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
586 req.nlh.nlmsg_len = sizeof(req);
587 req.nlh.nlmsg_type = cmd;
588 req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
589 req.nlh.nlmsg_pid = 0;
590 req.nlh.nlmsg_seq = 0;
592 req.rtm.rtm_dst_len = dst_len;
593 req.rtm.rtm_table = tb->n;
594 req.rtm.rtm_protocol = RTPROT_KERNEL;
595 req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
596 req.rtm.rtm_type = type;
599 rta.rta_prefsrc = &ifa->ifa_local;
600 rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
602 if (cmd == RTM_NEWROUTE)
603 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
605 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
608 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
611 fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
614 if (!(dev->flags&IFF_UP))
616 /* In the future, we will want to add default routes here */
621 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
624 struct net_device *dev;
625 struct dn_dev *dn_db;
626 struct dn_ifaddr *ifa2;
630 /* Scan device list */
631 read_lock(&dev_base_lock);
632 for(dev = dev_base; dev; dev = dev->next) {
636 for(ifa2 = dn_db->ifa_list; ifa2; ifa2 = ifa2->ifa_next) {
637 if (ifa2->ifa_local == ifa->ifa_local) {
643 read_unlock(&dev_base_lock);
646 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
648 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
649 if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
655 static void dn_fib_disable_addr(struct net_device *dev, int force)
657 if (dn_fib_sync_down(0, dev, force))
659 dn_rt_cache_flush(0);
660 neigh_ifdown(&dn_neigh_table, dev);
663 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
665 struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
669 dn_fib_add_ifaddr(ifa);
670 dn_fib_sync_up(ifa->ifa_dev->dev);
671 dn_rt_cache_flush(-1);
674 dn_fib_del_ifaddr(ifa);
675 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
676 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
678 dn_rt_cache_flush(-1);
685 int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
688 int scope = RT_SCOPE_NOWHERE;
695 * This makes no sense for DECnet.... we will almost
696 * certainly have more than one local address the same
697 * over all our interfaces. It needs thinking about
700 if (local && fi->fib_prefsrc == local) {
701 fi->fib_flags |= RTNH_F_DEAD;
703 } else if (dev && fi->fib_nhs) {
706 change_nexthops(fi) {
707 if (nh->nh_flags&RTNH_F_DEAD)
709 else if (nh->nh_dev == dev &&
710 nh->nh_scope != scope) {
711 spin_lock_bh(&dn_fib_multipath_lock);
712 nh->nh_flags |= RTNH_F_DEAD;
713 fi->fib_power -= nh->nh_power;
715 spin_unlock_bh(&dn_fib_multipath_lock);
718 } endfor_nexthops(fi)
719 if (dead == fi->fib_nhs) {
720 fi->fib_flags |= RTNH_F_DEAD;
729 int dn_fib_sync_up(struct net_device *dev)
733 if (!(dev->flags&IFF_UP))
739 change_nexthops(fi) {
740 if (!(nh->nh_flags&RTNH_F_DEAD)) {
744 if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
746 if (nh->nh_dev != dev || dev->dn_ptr == NULL)
749 spin_lock_bh(&dn_fib_multipath_lock);
751 nh->nh_flags &= ~RTNH_F_DEAD;
752 spin_unlock_bh(&dn_fib_multipath_lock);
753 } endfor_nexthops(fi);
756 fi->fib_flags &= ~RTNH_F_DEAD;
763 void dn_fib_flush(void)
766 struct dn_fib_table *tb;
769 for(id = RT_TABLE_MAX; id > 0; id--) {
770 if ((tb = dn_fib_get_table(id, 0)) == NULL)
772 flushed += tb->flush(tb);
776 dn_rt_cache_flush(-1);
779 static struct notifier_block dn_fib_dnaddr_notifier = {
780 .notifier_call = dn_fib_dnaddr_event,
783 void __exit dn_fib_cleanup(void)
785 dn_fib_table_cleanup();
786 dn_fib_rules_cleanup();
788 unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
792 void __init dn_fib_init(void)
798 register_dnaddr_notifier(&dn_fib_dnaddr_notifier);