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/*
* DECnet An implementation of the DECnet protocol suite for the LINUX
* operating system. DECnet is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* DECnet Routing Forwarding Information Base (Glue/Info List)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
*
*
* Changes:
* Alexey Kuznetsov : SMP locking changes
* Steve Whitehouse : Rewrote it... Well to be more correct, I
* copied most of it from the ipv4 fib code.
*
*/
#include <linux/config.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/dn.h>
#include <net/dn_route.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>
#define for_fib_info() { struct dn_fib_info *fi;\
for(fi = dn_fib_info_list; fi; fi = fi->fib_next)
#define endfor_fib_info() }
#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
#define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
#define endfor_nexthops(fi) }
extern int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb);
static struct dn_fib_info *dn_fib_info_list;
static rwlock_t dn_fib_info_lock = RW_LOCK_UNLOCKED;
int dn_fib_info_cnt;
static struct
{
int error;
u8 scope;
} dn_fib_props[RTA_MAX+1] = {
{ 0, RT_SCOPE_NOWHERE }, /* RTN_UNSPEC */
{ 0, RT_SCOPE_UNIVERSE }, /* RTN_UNICAST */
{ 0, RT_SCOPE_HOST }, /* RTN_LOCAL */
{ -EINVAL, RT_SCOPE_NOWHERE }, /* RTN_BROADCAST */
{ -EINVAL, RT_SCOPE_NOWHERE }, /* RTN_ANYCAST */
{ -EINVAL, RT_SCOPE_NOWHERE }, /* RTN_MULTICAST */
{ -EINVAL, RT_SCOPE_UNIVERSE }, /* RTN_BLACKHOLE */
{ -EHOSTUNREACH, RT_SCOPE_UNIVERSE }, /* RTN_UNREACHABLE */
{ -EACCES, RT_SCOPE_UNIVERSE }, /* RTN_PROHIBIT */
{ -EAGAIN, RT_SCOPE_UNIVERSE }, /* RTN_THROW */
{ -EINVAL, RT_SCOPE_NOWHERE }, /* RTN_NAT */
{ -EINVAL, RT_SCOPE_NOWHERE } /* RTN_XRESOLVE */
};
void dn_fib_free_info(struct dn_fib_info *fi)
{
if (fi->fib_dead == 0) {
printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n");
return;
}
change_nexthops(fi) {
if (nh->nh_dev)
dev_put(nh->nh_dev);
nh->nh_dev = NULL;
} endfor_nexthops(fi);
dn_fib_info_cnt--;
kfree(fi);
}
void dn_fib_release_info(struct dn_fib_info *fi)
{
write_lock(&dn_fib_info_lock);
if (fi && --fi->fib_treeref == 0) {
if (fi->fib_next)
fi->fib_next->fib_prev = fi->fib_prev;
if (fi->fib_prev)
fi->fib_prev->fib_next = fi->fib_next;
if (fi == dn_fib_info_list)
dn_fib_info_list = fi->fib_next;
fi->fib_dead = 1;
dn_fib_info_put(fi);
}
write_unlock(&dn_fib_info_lock);
}
static __inline__ int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi)
{
const struct dn_fib_nh *onh = ofi->fib_nh;
for_nexthops(fi) {
if (nh->nh_oif != onh->nh_oif ||
nh->nh_gw != onh->nh_gw ||
nh->nh_scope != onh->nh_scope ||
nh->nh_weight != onh->nh_weight ||
((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
return -1;
onh++;
} endfor_nexthops(fi);
return 0;
}
static __inline__ struct dn_fib_info *dn_fib_find_info(const struct dn_fib_info *nfi)
{
for_fib_info() {
if (fi->fib_nhs != nfi->fib_nhs)
continue;
if (nfi->fib_protocol == fi->fib_protocol &&
nfi->fib_prefsrc == fi->fib_prefsrc &&
nfi->fib_priority == fi->fib_priority &&
((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
(nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0))
return fi;
} endfor_fib_info();
return NULL;
}
u16 dn_fib_get_attr16(struct rtattr *attr, int attrlen, int type)
{
while(RTA_OK(attr,attrlen)) {
if (attr->rta_type == type)
return *(u16*)RTA_DATA(attr);
attr = RTA_NEXT(attr, attrlen);
}
return 0;
}
static int dn_fib_count_nhs(struct rtattr *rta)
{
int nhs = 0;
struct rtnexthop *nhp = RTA_DATA(rta);
int nhlen = RTA_PAYLOAD(rta);
while(nhlen >= (int)sizeof(struct rtnexthop)) {
if ((nhlen -= nhp->rtnh_len) < 0)
return 0;
nhs++;
nhp = RTNH_NEXT(nhp);
}
return nhs;
}
static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
{
struct rtnexthop *nhp = RTA_DATA(rta);
int nhlen = RTA_PAYLOAD(rta);
change_nexthops(fi) {
int attrlen = nhlen - sizeof(struct rtnexthop);
if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
return -EINVAL;
nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
nh->nh_oif = nhp->rtnh_ifindex;
nh->nh_weight = nhp->rtnh_hops + 1;
if (attrlen) {
nh->nh_gw = dn_fib_get_attr16(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
}
nhp = RTNH_NEXT(nhp);
} endfor_nexthops(fi);
return 0;
}
static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh)
{
int err;
if (nh->nh_gw) {
struct dn_fib_key key;
struct dn_fib_res res;
if (nh->nh_flags&RTNH_F_ONLINK) {
struct net_device *dev;
if (r->rtm_scope >= RT_SCOPE_LINK)
return -EINVAL;
if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
return -ENODEV;
if (!(dev->flags&IFF_UP))
return -ENETDOWN;
nh->nh_dev = dev;
atomic_inc(&dev->refcnt);
nh->nh_scope = RT_SCOPE_LINK;
return 0;
}
memset(&key, 0, sizeof(key));
key.dst = nh->nh_gw;
key.oif = nh->nh_oif;
key.scope = r->rtm_scope + 1;
if (key.scope < RT_SCOPE_LINK)
key.scope = RT_SCOPE_LINK;
if ((err = dn_fib_lookup(&key, &res)) != 0)
return err;
nh->nh_scope = res.scope;
nh->nh_oif = DN_FIB_RES_OIF(res);
nh->nh_dev = DN_FIB_RES_DEV(res);
if (nh->nh_dev)
atomic_inc(&nh->nh_dev->refcnt);
dn_fib_res_put(&res);
} else {
struct net_device *dev;
if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
return -EINVAL;
dev = __dev_get_by_index(nh->nh_oif);
if (dev == NULL || dev->dn_ptr == NULL)
return -ENODEV;
if (!(dev->flags&IFF_UP))
return -ENETDOWN;
nh->nh_dev = dev;
atomic_inc(&nh->nh_dev->refcnt);
nh->nh_scope = RT_SCOPE_HOST;
}
return 0;
}
struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct dn_kern_rta *rta, const struct nlmsghdr *nlh, int *errp)
{
int err;
struct dn_fib_info *fi = NULL;
struct dn_fib_info *ofi;
int nhs = 1;
if (dn_fib_props[r->rtm_type].scope > r->rtm_scope)
goto err_inval;
if (rta->rta_mp) {
nhs = dn_fib_count_nhs(rta->rta_mp);
if (nhs == 0)
goto err_inval;
}
fi = kmalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL);
err = -ENOBUFS;
if (fi == NULL)
goto failure;
memset(fi, 0, sizeof(*fi)+nhs*sizeof(struct dn_fib_nh));
fi->fib_protocol = r->rtm_protocol;
fi->fib_nhs = nhs;
fi->fib_flags = r->rtm_flags;
if (rta->rta_priority)
fi->fib_priority = *rta->rta_priority;
if (rta->rta_prefsrc)
memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 2);
if (rta->rta_mp) {
if ((err = dn_fib_get_nhs(fi, rta->rta_mp, r)) != 0)
goto failure;
if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
goto err_inval;
if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 2))
goto err_inval;
} else {
struct dn_fib_nh *nh = fi->fib_nh;
if (rta->rta_oif)
nh->nh_oif = *rta->rta_oif;
if (rta->rta_gw)
memcpy(&nh->nh_gw, rta->rta_gw, 2);
nh->nh_flags = r->rtm_flags;
nh->nh_weight = 1;
}
if (dn_fib_props[r->rtm_type].error) {
if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
goto err_inval;
goto link_it;
}
if (r->rtm_scope > RT_SCOPE_HOST)
goto err_inval;
if (r->rtm_scope == RT_SCOPE_HOST) {
struct dn_fib_nh *nh = fi->fib_nh;
/* Local address is added */
if (nhs != 1 || nh->nh_gw)
goto err_inval;
nh->nh_scope = RT_SCOPE_NOWHERE;
nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
err = -ENODEV;
if (nh->nh_dev == NULL)
goto failure;
} else {
change_nexthops(fi) {
if ((err = dn_fib_check_nh(r, fi, nh)) != 0)
goto failure;
} endfor_nexthops(fi)
}
#if I_GET_AROUND_TO_FIXING_PREFSRC
if (fi->fib_prefsrc) {
if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
memcmp(&fi->fib_prefsrc, rta->rta_dst, 2))
if (dn_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
goto err_inval;
}
#endif
link_it:
if ((ofi = dn_fib_find_info(fi)) != NULL) {
fi->fib_dead = 1;
dn_fib_free_info(fi);
ofi->fib_treeref++;
return ofi;
}
fi->fib_treeref++;
atomic_inc(&fi->fib_clntref);
write_lock(&dn_fib_info_lock);
fi->fib_next = dn_fib_info_list;
fi->fib_prev = NULL;
if (dn_fib_info_list)
dn_fib_info_list->fib_prev = fi;
dn_fib_info_list = fi;
dn_fib_info_cnt++;
write_unlock(&dn_fib_info_lock);
return fi;
err_inval:
err = -EINVAL;
failure:
*errp = err;
if (fi) {
fi->fib_dead = 1;
dn_fib_free_info(fi);
}
return NULL;
}
void dn_fib_select_multipath(const struct dn_fib_key *key, struct dn_fib_res *res)
{
struct dn_fib_info *fi = res->fi;
int w;
if (fi->fib_power <= 0) {
int power = 0;
change_nexthops(fi) {
if (!(nh->nh_flags&RTNH_F_DEAD)) {
power += nh->nh_weight;
nh->nh_power = nh->nh_weight;
}
} endfor_nexthops(fi);
fi->fib_power = power;
}
w = jiffies % fi->fib_power;
change_nexthops(fi) {
if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
if ((w -= nh->nh_power) <= 0) {
nh->nh_power--;
fi->fib_power--;
res->nh_sel = nhsel;
return;
}
}
} endfor_nexthops(fi);
printk(KERN_DEBUG "DECnet: BUG! dn_fib_select_multipath\n");
}
/*
* Punt to user via netlink for example, but for now
* we just drop it.
*/
int dn_fib_rt_message(struct sk_buff *skb)
{
kfree_skb(skb);
return 0;
}
static int dn_fib_check_attr(struct rtmsg *r, struct rtattr **rta)
{
int i;
for(i = 1; i <= RTA_MAX; i++) {
struct rtattr *attr = rta[i-1];
if (attr) {
if (RTA_PAYLOAD(attr) < 4 && RTA_PAYLOAD(attr) != 2)
return -EINVAL;
if (i != RTA_MULTIPATH && i != RTA_METRICS)
rta[i-1] = (struct rtattr *)RTA_DATA(attr);
}
}
return 0;
}
int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct dn_fib_table *tb;
struct rtattr **rta = arg;
struct rtmsg *r = NLMSG_DATA(nlh);
if (dn_fib_check_attr(r, rta))
return -EINVAL;
tb = dn_fib_get_table(r->rtm_table, 0);
if (tb)
return tb->delete(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
return -ESRCH;
}
int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct dn_fib_table *tb;
struct rtattr **rta = arg;
struct rtmsg *r = NLMSG_DATA(nlh);
if (dn_fib_check_attr(r, rta))
return -EINVAL;
tb = dn_fib_get_table(r->rtm_table, 1);
if (tb)
return tb->insert(tb, r, (struct dn_kern_rta *)rta, nlh, &NETLINK_CB(skb));
return -ENOBUFS;
}
int dn_fib_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
int t;
int s_t;
struct dn_fib_table *tb;
if (NLMSG_PAYLOAD(cb->nlh, 0) >= sizeof(struct rtmsg) &&
((struct rtmsg *)NLMSG_DATA(cb->nlh))->rtm_flags&RTM_F_CLONED)
return dn_cache_dump(skb, cb);
s_t = cb->args[0];
if (s_t == 0)
s_t = cb->args[0] = DN_MIN_TABLE;
for(t = s_t; t < DN_NUM_TABLES; t++) {
if (t < s_t)
continue;
if (t > s_t)
memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(int));
tb = dn_fib_get_table(t, 0);
if (tb == NULL)
continue;
if (tb->dump(tb, skb, cb) < 0)
break;
}
cb->args[0] = t;
return skb->len;
}
int dn_fib_sync_down(dn_address local, struct net_device *dev, int force)
{
int ret = 0;
int scope = RT_SCOPE_NOWHERE;
if (force)
scope = -1;
for_fib_info() {
/*
* This makes no sense for DECnet.... we will almost
* certainly have more than one local address the same
* over all our interfaces. It needs thinking about
* some more.
*/
if (local && fi->fib_prefsrc == local) {
fi->fib_flags |= RTNH_F_DEAD;
ret++;
} else if (dev && fi->fib_nhs) {
int dead = 0;
change_nexthops(fi) {
if (nh->nh_flags&RTNH_F_DEAD)
dead++;
else if (nh->nh_dev == dev &&
nh->nh_scope != scope) {
nh->nh_flags |= RTNH_F_DEAD;
fi->fib_power -= nh->nh_power;
nh->nh_power = 0;
dead++;
}
} endfor_nexthops(fi)
if (dead == fi->fib_nhs) {
fi->fib_flags |= RTNH_F_DEAD;
ret++;
}
}
} endfor_fib_info();
return ret;
}
int dn_fib_sync_up(struct net_device *dev)
{
int ret = 0;
if (!(dev->flags&IFF_UP))
return 0;
for_fib_info() {
int alive = 0;
change_nexthops(fi) {
if (!(nh->nh_flags&RTNH_F_DEAD)) {
alive++;
continue;
}
if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
continue;
if (nh->nh_dev != dev || dev->dn_ptr == NULL)
continue;
alive++;
nh->nh_power = 0;
nh->nh_flags &= ~RTNH_F_DEAD;
} endfor_nexthops(fi);
if (alive == fi->fib_nhs) {
fi->fib_flags &= ~RTNH_F_DEAD;
ret++;
}
} endfor_fib_info();
return ret;
}
void dn_fib_flush(void)
{
int flushed = 0;
struct dn_fib_table *tb;
int id;
for(id = DN_NUM_TABLES; id > 0; id--) {
if ((tb = dn_fib_get_table(id, 0)) == NULL)
continue;
flushed += tb->flush(tb);
}
if (flushed)
dn_rt_cache_flush(-1);
}
int dn_fib_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
if (!capable(CAP_NET_ADMIN))
return -EPERM;
switch(cmd) {
case SIOCADDRT:
case SIOCDELRT:
return 0;
}
return -EINVAL;
}
#ifdef CONFIG_PROC_FS
static int decnet_rt_get_info(char *buffer, char **start, off_t offset, int length)
{
int first = offset / 128;
char *ptr = buffer;
int count = (length + 127) / 128;
int len;
int i;
struct dn_fib_table *tb;
*start = buffer + (offset % 128);
if (--first < 0) {
sprintf(buffer, "%-127s\n", "Iface\tDest\tGW \tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU\tWindow\tIRTT");
--count;
ptr += 128;
first = 0;
}
for(i = DN_MIN_TABLE; (i <= DN_NUM_TABLES) && (count > 0); i++) {
if ((tb = dn_fib_get_table(i, 0)) != NULL) {
int n = tb->get_info(tb, ptr, first, count);
count -= n;
ptr += n * 128;
}
}
len = ptr - *start;
if (len >= length)
return length;
if (len >= 0)
return len;
return 0;
}
#endif /* CONFIG_PROC_FS */
void __exit dn_fib_cleanup(void)
{
proc_net_remove("decnet_route");
dn_fib_table_cleanup();
dn_fib_rules_cleanup();
}
void __init dn_fib_init(void)
{
#ifdef CONFIG_PROC_FS
proc_net_create("decnet_route", 0, decnet_rt_get_info);
#endif
dn_fib_table_init();
dn_fib_rules_init();
}
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