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>
37 #include <net/fib_rules.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 static DEFINE_SPINLOCK(dn_fib_multipath_lock);
59 static struct dn_fib_info *dn_fib_info_list;
60 static DEFINE_SPINLOCK(dn_fib_info_lock);
66 } dn_fib_props[RTN_MAX+1] = {
67 [RTN_UNSPEC] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
68 [RTN_UNICAST] = { .error = 0, .scope = RT_SCOPE_UNIVERSE },
69 [RTN_LOCAL] = { .error = 0, .scope = RT_SCOPE_HOST },
70 [RTN_BROADCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
71 [RTN_ANYCAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
72 [RTN_MULTICAST] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
73 [RTN_BLACKHOLE] = { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
74 [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
75 [RTN_PROHIBIT] = { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
76 [RTN_THROW] = { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
77 [RTN_NAT] = { .error = 0, .scope = RT_SCOPE_NOWHERE },
78 [RTN_XRESOLVE] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
81 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
82 static int dn_fib_sync_up(struct net_device *dev);
84 void dn_fib_free_info(struct dn_fib_info *fi)
86 if (fi->fib_dead == 0) {
87 printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
95 } endfor_nexthops(fi);
99 void dn_fib_release_info(struct dn_fib_info *fi)
101 spin_lock(&dn_fib_info_lock);
102 if (fi && --fi->fib_treeref == 0) {
104 fi->fib_next->fib_prev = fi->fib_prev;
106 fi->fib_prev->fib_next = fi->fib_next;
107 if (fi == dn_fib_info_list)
108 dn_fib_info_list = fi->fib_next;
112 spin_unlock(&dn_fib_info_lock);
115 static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
117 const struct dn_fib_nh *onh = ofi->fib_nh;
120 if (nh->nh_oif != onh->nh_oif ||
121 nh->nh_gw != onh->nh_gw ||
122 nh->nh_scope != onh->nh_scope ||
123 nh->nh_weight != onh->nh_weight ||
124 ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
127 } endfor_nexthops(fi);
131 static inline struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
134 if (fi->fib_nhs != nfi->fib_nhs)
136 if (nfi->fib_protocol == fi->fib_protocol &&
137 nfi->fib_prefsrc == fi->fib_prefsrc &&
138 nfi->fib_priority == fi->fib_priority &&
139 memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 &&
140 ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
141 (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
147 __le16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
149 while(RTA_OK(attr,attrlen)) {
150 if (attr->rta_type == type)
151 return *(__le16*)RTA_DATA(attr);
152 attr = RTA_NEXT(attr, attrlen);
158 static int dn_fib_count_nhs(struct rtattr *rta)
161 struct rtnexthop *nhp = RTA_DATA(rta);
162 int nhlen = RTA_PAYLOAD(rta);
164 while(nhlen >= (int)sizeof(struct rtnexthop)) {
165 if ((nhlen -= nhp->rtnh_len) < 0)
168 nhp = RTNH_NEXT(nhp);
174 static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
176 struct rtnexthop *nhp = RTA_DATA(rta);
177 int nhlen = RTA_PAYLOAD(rta);
179 change_nexthops(fi) {
180 int attrlen = nhlen - sizeof(struct rtnexthop);
181 if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
184 nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
185 nh->nh_oif = nhp->rtnh_ifindex;
186 nh->nh_weight = nhp->rtnh_hops + 1;
189 nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
191 nhp = RTNH_NEXT(nhp);
192 } endfor_nexthops(fi);
198 static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
204 struct dn_fib_res res;
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(&init_net, 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(&init_net, 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 (r->rtm_type > RTN_MAX)
280 if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
284 nhs = dn_fib_count_nhs(rta->rta_mp);
289 fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
294 fi->fib_protocol = r->rtm_protocol;
296 fi->fib_flags = r->rtm_flags;
297 if (rta->rta_priority)
298 fi->fib_priority = *rta->rta_priority;
300 int attrlen = RTA_PAYLOAD(rta->rta_mx);
301 struct rtattr *attr = RTA_DATA(rta->rta_mx);
303 while(RTA_OK(attr, attrlen)) {
304 unsigned flavour = attr->rta_type;
306 if (flavour > RTAX_MAX)
308 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
310 attr = RTA_NEXT(attr, attrlen);
313 if (rta->rta_prefsrc)
314 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
317 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
319 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
321 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
324 struct dn_fib_nh *nh = fi->fib_nh;
326 nh->nh_oif = *rta->rta_oif;
328 memcpy(&nh->nh_gw, rta->rta_gw, 2);
329 nh->nh_flags = r->rtm_flags;
333 if (r->rtm_type == RTN_NAT) {
334 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
336 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
340 if (dn_fib_props[r->rtm_type].error) {
341 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
346 if (r->rtm_scope > RT_SCOPE_HOST)
349 if (r->rtm_scope == RT_SCOPE_HOST) {
350 struct dn_fib_nh *nh = fi->fib_nh;
352 /* Local address is added */
353 if (nhs != 1 || nh->nh_gw)
355 nh->nh_scope = RT_SCOPE_NOWHERE;
356 nh->nh_dev = dev_get_by_index(&init_net, fi->fib_nh->nh_oif);
358 if (nh->nh_dev == NULL)
361 change_nexthops(fi) {
362 if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
364 } endfor_nexthops(fi)
367 if (fi->fib_prefsrc) {
368 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
369 memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
370 if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
375 if ((ofi = dn_fib_find_info(fi)) != NULL) {
377 dn_fib_free_info(fi);
383 atomic_inc(&fi->fib_clntref);
384 spin_lock(&dn_fib_info_lock);
385 fi->fib_next = dn_fib_info_list;
387 if (dn_fib_info_list)
388 dn_fib_info_list->fib_prev = fi;
389 dn_fib_info_list = fi;
390 spin_unlock(&dn_fib_info_lock);
400 dn_fib_free_info(fi);
406 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
408 int err = dn_fib_props[type].error;
411 if (fi->fib_flags & RTNH_F_DEAD)
418 DN_FIB_RES_RESET(*res);
419 atomic_inc(&fi->fib_clntref);
424 if (nh->nh_flags & RTNH_F_DEAD)
426 if (!fl->oif || fl->oif == nh->nh_oif)
429 if (nhsel < fi->fib_nhs) {
431 atomic_inc(&fi->fib_clntref);
439 printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
447 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
449 struct dn_fib_info *fi = res->fi;
452 spin_lock_bh(&dn_fib_multipath_lock);
453 if (fi->fib_power <= 0) {
455 change_nexthops(fi) {
456 if (!(nh->nh_flags&RTNH_F_DEAD)) {
457 power += nh->nh_weight;
458 nh->nh_power = nh->nh_weight;
460 } endfor_nexthops(fi);
461 fi->fib_power = power;
463 spin_unlock_bh(&dn_fib_multipath_lock);
469 w = jiffies % fi->fib_power;
471 change_nexthops(fi) {
472 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
473 if ((w -= nh->nh_power) <= 0) {
477 spin_unlock_bh(&dn_fib_multipath_lock);
481 } endfor_nexthops(fi);
483 spin_unlock_bh(&dn_fib_multipath_lock);
487 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
491 for(i = 1; i <= RTA_MAX; i++) {
492 struct rtattr *attr = rta[i-1];
494 if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
496 if (i != RTA_MULTIPATH && i != RTA_METRICS &&
498 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
505 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
507 struct net *net = sock_net(skb->sk);
508 struct dn_fib_table *tb;
509 struct rtattr **rta = arg;
510 struct rtmsg *r = NLMSG_DATA(nlh);
512 if (net != &init_net)
515 if (dn_fib_check_attr(r, rta))
518 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
520 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
525 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
527 struct net *net = sock_net(skb->sk);
528 struct dn_fib_table *tb;
529 struct rtattr **rta = arg;
530 struct rtmsg *r = NLMSG_DATA(nlh);
532 if (net != &init_net)
535 if (dn_fib_check_attr(r, rta))
538 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
540 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
545 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
547 struct dn_fib_table *tb;
552 struct dn_kern_rta rta;
554 memset(&req.rtm, 0, sizeof(req.rtm));
555 memset(&rta, 0, sizeof(rta));
557 if (type == RTN_UNICAST)
558 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
560 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
565 req.nlh.nlmsg_len = sizeof(req);
566 req.nlh.nlmsg_type = cmd;
567 req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
568 req.nlh.nlmsg_pid = 0;
569 req.nlh.nlmsg_seq = 0;
571 req.rtm.rtm_dst_len = dst_len;
572 req.rtm.rtm_table = tb->n;
573 req.rtm.rtm_protocol = RTPROT_KERNEL;
574 req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
575 req.rtm.rtm_type = type;
578 rta.rta_prefsrc = &ifa->ifa_local;
579 rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
581 if (cmd == RTM_NEWROUTE)
582 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
584 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
587 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
590 fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
593 if (!(dev->flags&IFF_UP))
595 /* In the future, we will want to add default routes here */
600 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
603 struct net_device *dev;
604 struct dn_dev *dn_db;
605 struct dn_ifaddr *ifa2;
609 /* Scan device list */
610 read_lock(&dev_base_lock);
611 for_each_netdev(&init_net, dev) {
615 for(ifa2 = dn_db->ifa_list; ifa2; ifa2 = ifa2->ifa_next) {
616 if (ifa2->ifa_local == ifa->ifa_local) {
622 read_unlock(&dev_base_lock);
625 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
627 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
628 if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
634 static void dn_fib_disable_addr(struct net_device *dev, int force)
636 if (dn_fib_sync_down(0, dev, force))
638 dn_rt_cache_flush(0);
639 neigh_ifdown(&dn_neigh_table, dev);
642 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
644 struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
648 dn_fib_add_ifaddr(ifa);
649 dn_fib_sync_up(ifa->ifa_dev->dev);
650 dn_rt_cache_flush(-1);
653 dn_fib_del_ifaddr(ifa);
654 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
655 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
657 dn_rt_cache_flush(-1);
664 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
667 int scope = RT_SCOPE_NOWHERE;
674 * This makes no sense for DECnet.... we will almost
675 * certainly have more than one local address the same
676 * over all our interfaces. It needs thinking about
679 if (local && fi->fib_prefsrc == local) {
680 fi->fib_flags |= RTNH_F_DEAD;
682 } else if (dev && fi->fib_nhs) {
685 change_nexthops(fi) {
686 if (nh->nh_flags&RTNH_F_DEAD)
688 else if (nh->nh_dev == dev &&
689 nh->nh_scope != scope) {
690 spin_lock_bh(&dn_fib_multipath_lock);
691 nh->nh_flags |= RTNH_F_DEAD;
692 fi->fib_power -= nh->nh_power;
694 spin_unlock_bh(&dn_fib_multipath_lock);
697 } endfor_nexthops(fi)
698 if (dead == fi->fib_nhs) {
699 fi->fib_flags |= RTNH_F_DEAD;
708 static int dn_fib_sync_up(struct net_device *dev)
712 if (!(dev->flags&IFF_UP))
718 change_nexthops(fi) {
719 if (!(nh->nh_flags&RTNH_F_DEAD)) {
723 if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
725 if (nh->nh_dev != dev || dev->dn_ptr == NULL)
728 spin_lock_bh(&dn_fib_multipath_lock);
730 nh->nh_flags &= ~RTNH_F_DEAD;
731 spin_unlock_bh(&dn_fib_multipath_lock);
732 } endfor_nexthops(fi);
735 fi->fib_flags &= ~RTNH_F_DEAD;
742 static struct notifier_block dn_fib_dnaddr_notifier = {
743 .notifier_call = dn_fib_dnaddr_event,
746 void __exit dn_fib_cleanup(void)
748 dn_fib_table_cleanup();
749 dn_fib_rules_cleanup();
751 unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
755 void __init dn_fib_init(void)
760 register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
762 rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL);
763 rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL);