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
);