dn_fib.c

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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;
}


#ifdef CONFIG_RTNETLINK

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;
}
#endif /* CONFIG_RTNETLINK */

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)
{
#ifdef CONFIG_PROC_FS
	proc_net_remove("decnet_route");
#endif

	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();
}