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 memset(&fl, 0, sizeof(fl));
208 if (nh->nh_flags&RTNH_F_ONLINK) {
209 struct net_device *dev;
211 if (r->rtm_scope >= RT_SCOPE_LINK)
213 if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST)
215 if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
217 if (!(dev->flags&IFF_UP))
221 nh->nh_scope = RT_SCOPE_LINK;
225 memset(&fl, 0, sizeof(fl));
226 fl.fld_dst = nh->nh_gw;
228 fl.fld_scope = r->rtm_scope + 1;
230 if (fl.fld_scope < RT_SCOPE_LINK)
231 fl.fld_scope = RT_SCOPE_LINK;
233 if ((err = dn_fib_lookup(&fl, &res)) != 0)
237 if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
239 nh->nh_scope = res.scope;
240 nh->nh_oif = DN_FIB_RES_OIF(res);
241 nh->nh_dev = DN_FIB_RES_DEV(res);
242 if (nh->nh_dev == NULL)
244 dev_hold(nh->nh_dev);
246 if (!(nh->nh_dev->flags & IFF_UP))
250 dn_fib_res_put(&res);
253 struct net_device *dev;
255 if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
258 dev = __dev_get_by_index(nh->nh_oif);
259 if (dev == NULL || dev->dn_ptr == NULL)
261 if (!(dev->flags&IFF_UP))
264 dev_hold(nh->nh_dev);
265 nh->nh_scope = RT_SCOPE_HOST;
272 struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
275 struct dn_fib_info *fi = NULL;
276 struct dn_fib_info *ofi;
279 if (r->rtm_type > RTN_MAX)
282 if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
286 nhs = dn_fib_count_nhs(rta->rta_mp);
291 fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
296 fi->fib_protocol = r->rtm_protocol;
298 fi->fib_flags = r->rtm_flags;
299 if (rta->rta_priority)
300 fi->fib_priority = *rta->rta_priority;
302 int attrlen = RTA_PAYLOAD(rta->rta_mx);
303 struct rtattr *attr = RTA_DATA(rta->rta_mx);
305 while(RTA_OK(attr, attrlen)) {
306 unsigned flavour = attr->rta_type;
308 if (flavour > RTAX_MAX)
310 fi->fib_metrics[flavour-1] = *(unsigned*)RTA_DATA(attr);
312 attr = RTA_NEXT(attr, attrlen);
315 if (rta->rta_prefsrc)
316 memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
319 if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
321 if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
323 if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
326 struct dn_fib_nh *nh = fi->fib_nh;
328 nh->nh_oif = *rta->rta_oif;
330 memcpy(&nh->nh_gw, rta->rta_gw, 2);
331 nh->nh_flags = r->rtm_flags;
335 if (r->rtm_type == RTN_NAT) {
336 if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
338 memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 2);
342 if (dn_fib_props[r->rtm_type].error) {
343 if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
348 if (r->rtm_scope > RT_SCOPE_HOST)
351 if (r->rtm_scope == RT_SCOPE_HOST) {
352 struct dn_fib_nh *nh = fi->fib_nh;
354 /* Local address is added */
355 if (nhs != 1 || nh->nh_gw)
357 nh->nh_scope = RT_SCOPE_NOWHERE;
358 nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
360 if (nh->nh_dev == NULL)
363 change_nexthops(fi) {
364 if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
366 } endfor_nexthops(fi)
369 if (fi->fib_prefsrc) {
370 if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
371 memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
372 if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
377 if ((ofi = dn_fib_find_info(fi)) != NULL) {
379 dn_fib_free_info(fi);
385 atomic_inc(&fi->fib_clntref);
386 spin_lock(&dn_fib_info_lock);
387 fi->fib_next = dn_fib_info_list;
389 if (dn_fib_info_list)
390 dn_fib_info_list->fib_prev = fi;
391 dn_fib_info_list = fi;
392 spin_unlock(&dn_fib_info_lock);
402 dn_fib_free_info(fi);
408 int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowi *fl, struct dn_fib_res *res)
410 int err = dn_fib_props[type].error;
413 if (fi->fib_flags & RTNH_F_DEAD)
420 DN_FIB_RES_RESET(*res);
421 atomic_inc(&fi->fib_clntref);
426 if (nh->nh_flags & RTNH_F_DEAD)
428 if (!fl->oif || fl->oif == nh->nh_oif)
431 if (nhsel < fi->fib_nhs) {
433 atomic_inc(&fi->fib_clntref);
441 printk("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type);
449 void dn_fib_select_multipath(const struct flowi *fl, struct dn_fib_res *res)
451 struct dn_fib_info *fi = res->fi;
454 spin_lock_bh(&dn_fib_multipath_lock);
455 if (fi->fib_power <= 0) {
457 change_nexthops(fi) {
458 if (!(nh->nh_flags&RTNH_F_DEAD)) {
459 power += nh->nh_weight;
460 nh->nh_power = nh->nh_weight;
462 } endfor_nexthops(fi);
463 fi->fib_power = power;
465 spin_unlock_bh(&dn_fib_multipath_lock);
471 w = jiffies % fi->fib_power;
473 change_nexthops(fi) {
474 if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
475 if ((w -= nh->nh_power) <= 0) {
479 spin_unlock_bh(&dn_fib_multipath_lock);
483 } endfor_nexthops(fi);
485 spin_unlock_bh(&dn_fib_multipath_lock);
489 static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
493 for(i = 1; i <= RTA_MAX; i++) {
494 struct rtattr *attr = rta[i-1];
496 if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
498 if (i != RTA_MULTIPATH && i != RTA_METRICS &&
500 rta[i-1] = (struct rtattr *)RTA_DATA(attr);
507 static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
509 struct dn_fib_table *tb;
510 struct rtattr **rta = arg;
511 struct rtmsg *r = NLMSG_DATA(nlh);
513 if (dn_fib_check_attr(r, rta))
516 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 0);
518 return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
523 static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
525 struct dn_fib_table *tb;
526 struct rtattr **rta = arg;
527 struct rtmsg *r = NLMSG_DATA(nlh);
529 if (dn_fib_check_attr(r, rta))
532 tb = dn_fib_get_table(rtm_get_table(rta, r->rtm_table), 1);
534 return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
539 static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa)
541 struct dn_fib_table *tb;
546 struct dn_kern_rta rta;
548 memset(&req.rtm, 0, sizeof(req.rtm));
549 memset(&rta, 0, sizeof(rta));
551 if (type == RTN_UNICAST)
552 tb = dn_fib_get_table(RT_MIN_TABLE, 1);
554 tb = dn_fib_get_table(RT_TABLE_LOCAL, 1);
559 req.nlh.nlmsg_len = sizeof(req);
560 req.nlh.nlmsg_type = cmd;
561 req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_APPEND;
562 req.nlh.nlmsg_pid = 0;
563 req.nlh.nlmsg_seq = 0;
565 req.rtm.rtm_dst_len = dst_len;
566 req.rtm.rtm_table = tb->n;
567 req.rtm.rtm_protocol = RTPROT_KERNEL;
568 req.rtm.rtm_scope = (type != RTN_LOCAL ? RT_SCOPE_LINK : RT_SCOPE_HOST);
569 req.rtm.rtm_type = type;
572 rta.rta_prefsrc = &ifa->ifa_local;
573 rta.rta_oif = &ifa->ifa_dev->dev->ifindex;
575 if (cmd == RTM_NEWROUTE)
576 tb->insert(tb, &req.rtm, &rta, &req.nlh, NULL);
578 tb->delete(tb, &req.rtm, &rta, &req.nlh, NULL);
581 static void dn_fib_add_ifaddr(struct dn_ifaddr *ifa)
584 fib_magic(RTM_NEWROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
587 if (!(dev->flags&IFF_UP))
589 /* In the future, we will want to add default routes here */
594 static void dn_fib_del_ifaddr(struct dn_ifaddr *ifa)
597 struct net_device *dev;
598 struct dn_dev *dn_db;
599 struct dn_ifaddr *ifa2;
603 /* Scan device list */
604 read_lock(&dev_base_lock);
605 for_each_netdev(dev) {
609 for(ifa2 = dn_db->ifa_list; ifa2; ifa2 = ifa2->ifa_next) {
610 if (ifa2->ifa_local == ifa->ifa_local) {
616 read_unlock(&dev_base_lock);
619 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 16, ifa);
621 if (dnet_addr_type(ifa->ifa_local) != RTN_LOCAL) {
622 if (dn_fib_sync_down(ifa->ifa_local, NULL, 0))
628 static void dn_fib_disable_addr(struct net_device *dev, int force)
630 if (dn_fib_sync_down(0, dev, force))
632 dn_rt_cache_flush(0);
633 neigh_ifdown(&dn_neigh_table, dev);
636 static int dn_fib_dnaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
638 struct dn_ifaddr *ifa = (struct dn_ifaddr *)ptr;
642 dn_fib_add_ifaddr(ifa);
643 dn_fib_sync_up(ifa->ifa_dev->dev);
644 dn_rt_cache_flush(-1);
647 dn_fib_del_ifaddr(ifa);
648 if (ifa->ifa_dev && ifa->ifa_dev->ifa_list == NULL) {
649 dn_fib_disable_addr(ifa->ifa_dev->dev, 1);
651 dn_rt_cache_flush(-1);
658 static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force)
661 int scope = RT_SCOPE_NOWHERE;
668 * This makes no sense for DECnet.... we will almost
669 * certainly have more than one local address the same
670 * over all our interfaces. It needs thinking about
673 if (local && fi->fib_prefsrc == local) {
674 fi->fib_flags |= RTNH_F_DEAD;
676 } else if (dev && fi->fib_nhs) {
679 change_nexthops(fi) {
680 if (nh->nh_flags&RTNH_F_DEAD)
682 else if (nh->nh_dev == dev &&
683 nh->nh_scope != scope) {
684 spin_lock_bh(&dn_fib_multipath_lock);
685 nh->nh_flags |= RTNH_F_DEAD;
686 fi->fib_power -= nh->nh_power;
688 spin_unlock_bh(&dn_fib_multipath_lock);
691 } endfor_nexthops(fi)
692 if (dead == fi->fib_nhs) {
693 fi->fib_flags |= RTNH_F_DEAD;
702 static int dn_fib_sync_up(struct net_device *dev)
706 if (!(dev->flags&IFF_UP))
712 change_nexthops(fi) {
713 if (!(nh->nh_flags&RTNH_F_DEAD)) {
717 if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
719 if (nh->nh_dev != dev || dev->dn_ptr == NULL)
722 spin_lock_bh(&dn_fib_multipath_lock);
724 nh->nh_flags &= ~RTNH_F_DEAD;
725 spin_unlock_bh(&dn_fib_multipath_lock);
726 } endfor_nexthops(fi);
729 fi->fib_flags &= ~RTNH_F_DEAD;
736 static struct notifier_block dn_fib_dnaddr_notifier = {
737 .notifier_call = dn_fib_dnaddr_event,
740 void __exit dn_fib_cleanup(void)
742 dn_fib_table_cleanup();
743 dn_fib_rules_cleanup();
745 unregister_dnaddr_notifier(&dn_fib_dnaddr_notifier);
749 void __init dn_fib_init(void)
754 register_dnaddr_notifier(&dn_fib_dnaddr_notifier);
756 rtnl_register(PF_DECnet, RTM_NEWROUTE, dn_fib_rtm_newroute, NULL);
757 rtnl_register(PF_DECnet, RTM_DELROUTE, dn_fib_rtm_delroute, NULL);