/*
* 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 (Routing Tables)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
* Mostly copied from the IPv4 routing code
*
*
* Changes:
*
*/
#include <linux/string.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/slab.h>
#include <linux/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <asm/uaccess.h>
#include <linux/route.h> /* RTF_xxx */
#include <net/neighbour.h>
#include <net/netlink.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.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>
struct dn_zone
{
struct dn_zone *dz_next;
struct dn_fib_node **dz_hash;
int dz_nent;
int dz_divisor;
u32 dz_hashmask;
#define DZ_HASHMASK(dz) ((dz)->dz_hashmask)
int dz_order;
__le16 dz_mask;
#define DZ_MASK(dz) ((dz)->dz_mask)
};
struct dn_hash
{
struct dn_zone *dh_zones[17];
struct dn_zone *dh_zone_list;
};
#define dz_key_0(key) ((key).datum = 0)
#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 endfor_nexthops(fi) }
#define DN_MAX_DIVISOR 1024
#define DN_S_ZOMBIE 1
#define DN_S_ACCESSED 2
#define DN_FIB_SCAN(f, fp) \
for( ; ((f) = *(fp)) != NULL; (fp) = &(f)->fn_next)
#define DN_FIB_SCAN_KEY(f, fp, key) \
for( ; ((f) = *(fp)) != NULL && dn_key_eq((f)->fn_key, (key)); (fp) = &(f)->fn_next)
#define RT_TABLE_MIN 1
#define DN_FIB_TABLE_HASHSZ 256
static struct hlist_head dn_fib_table_hash[DN_FIB_TABLE_HASHSZ];
static DEFINE_RWLOCK(dn_fib_tables_lock);
static struct kmem_cache *dn_hash_kmem __read_mostly;
static int dn_fib_hash_zombies;
static inline dn_fib_idx_t dn_hash(dn_fib_key_t key, struct dn_zone *dz)
{
u16 h = le16_to_cpu(key.datum)>>(16 - dz->dz_order);
h ^= (h >> 10);
h ^= (h >> 6);
h &= DZ_HASHMASK(dz);
return *(dn_fib_idx_t *)&h;
}
static inline dn_fib_key_t dz_key(__le16 dst, struct dn_zone *dz)
{
dn_fib_key_t k;
k.datum = dst & DZ_MASK(dz);
return k;
}
static inline struct dn_fib_node **dn_chain_p(dn_fib_key_t key, struct dn_zone *dz)
{
return &dz->dz_hash[dn_hash(key, dz).datum];
}
static inline struct dn_fib_node *dz_chain(dn_fib_key_t key, struct dn_zone *dz)
{
return dz->dz_hash[dn_hash(key, dz).datum];
}
static inline int dn_key_eq(dn_fib_key_t a, dn_fib_key_t b)
{
return a.datum == b.datum;
}
static inline int dn_key_leq(dn_fib_key_t a, dn_fib_key_t b)
{
return a.datum <= b.datum;
}
static inline void dn_rebuild_zone(struct dn_zone *dz,
struct dn_fib_node **old_ht,
int old_divisor)
{
struct dn_fib_node *f, **fp, *next;
int i;
for(i = 0; i < old_divisor; i++) {
for(f = old_ht[i]; f; f = next) {
next = f->fn_next;
for(fp = dn_chain_p(f->fn_key, dz);
*fp && dn_key_leq((*fp)->fn_key, f->fn_key);
fp = &(*fp)->fn_next)
/* NOTHING */;
f->fn_next = *fp;
*fp = f;
}
}
}
static void dn_rehash_zone(struct dn_zone *dz)
{
struct dn_fib_node **ht, **old_ht;
int old_divisor, new_divisor;
u32 new_hashmask;
old_divisor = dz->dz_divisor;
switch (old_divisor) {
case 16:
new_divisor = 256;
new_hashmask = 0xFF;
break;
default:
printk(KERN_DEBUG "DECnet: dn_rehash_zone: BUG! %d\n",
old_divisor);
case 256:
new_divisor = 1024;
new_hashmask = 0x3FF;
break;
}
ht = kcalloc(new_divisor, sizeof(struct dn_fib_node*), GFP_KERNEL);
if (ht == NULL)
return;
write_lock_bh(&dn_fib_tables_lock);
old_ht = dz->dz_hash;
dz->dz_hash = ht;
dz->dz_hashmask = new_hashmask;
dz->dz_divisor = new_divisor;
dn_rebuild_zone(dz, old_ht, old_divisor);
write_unlock_bh(&dn_fib_tables_lock);
kfree(old_ht);
}
static void dn_free_node(struct dn_fib_node *f)
{
dn_fib_release_info(DN_FIB_INFO(f));
kmem_cache_free(dn_hash_kmem, f);
}
static struct dn_zone *dn_new_zone(struct dn_hash *table, int z)
{
int i;
struct dn_zone *dz = kzalloc(sizeof(struct dn_zone), GFP_KERNEL);
if (!dz)
return NULL;
if (z) {
dz->dz_divisor = 16;
dz->dz_hashmask = 0x0F;
} else {
dz->dz_divisor = 1;
dz->dz_hashmask = 0;
}
dz->dz_hash = kcalloc(dz->dz_divisor, sizeof(struct dn_fib_node *), GFP_KERNEL);
if (!dz->dz_hash) {
kfree(dz);
return NULL;
}
dz->dz_order = z;
dz->dz_mask = dnet_make_mask(z);
for(i = z + 1; i <= 16; i++)
if (table->dh_zones[i])
break;
write_lock_bh(&dn_fib_tables_lock);
if (i>16) {
dz->dz_next = table->dh_zone_list;
table->dh_zone_list = dz;
} else {
dz->dz_next = table->dh_zones[i]->dz_next;
table->dh_zones[i]->dz_next = dz;
}
table->dh_zones[z] = dz;
write_unlock_bh(&dn_fib_tables_lock);
return dz;
}
static int dn_fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct nlattr *attrs[], struct dn_fib_info *fi)
{
struct rtnexthop *nhp;
int nhlen;
if (attrs[RTA_PRIORITY] &&
nla_get_u32(attrs[RTA_PRIORITY]) != fi->fib_priority)
return 1;
if (attrs[RTA_OIF] || attrs[RTA_GATEWAY]) {
if ((!attrs[RTA_OIF] || nla_get_u32(attrs[RTA_OIF]) == fi->fib_nh->nh_oif) &&
(!attrs[RTA_GATEWAY] || nla_get_le16(attrs[RTA_GATEWAY]) != fi->fib_nh->nh_gw))
return 0;
return 1;
}
if (!attrs[RTA_MULTIPATH])
return 0;
nhp = nla_data(attrs[RTA_MULTIPATH]);
nhlen = nla_len(attrs[RTA_MULTIPATH]);
for_nexthops(fi) {
int attrlen = nhlen - sizeof(struct rtnexthop);
__le16 gw;
if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
return -EINVAL;
if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
return 1;
if (attrlen) {
struct nlattr *gw_attr;
gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY);
gw = gw_attr ? nla_get_le16(gw_attr) : 0;
if (gw && gw != nh->nh_gw)
return 1;
}
nhp = RTNH_NEXT(nhp);
} endfor_nexthops(fi);
return 0;
}
static inline size_t dn_fib_nlmsg_size(struct dn_fib_info *fi)
{
size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg))
+ nla_total_size(4) /* RTA_TABLE */
+ nla_total_size(2) /* RTA_DST */
+ nla_total_size(4); /* RTA_PRIORITY */
/* space for nested metrics */
payload += nla_total_size((RTAX_MAX * nla_total_size(4)));
if (fi->fib_nhs) {
/* Also handles the special case fib_nhs == 1 */
/* each nexthop is packed in an attribute */
size_t nhsize = nla_total_size(sizeof(struct rtnexthop));
/* may contain a gateway attribute */
nhsize += nla_total_size(4);
/* all nexthops are packed in a nested attribute */
payload += nla_total_size(fi->fib_nhs * nhsize);
}
return payload;
}
static int dn_fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
u32 tb_id, u8 type, u8 scope, void *dst, int dst_len,
struct dn_fib_info *fi, unsigned int flags)
{
struct rtmsg *rtm;
struct nlmsghdr *nlh;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags);
if (!nlh)
return -EMSGSIZE;
rtm = nlmsg_data(nlh);
rtm->rtm_family = AF_DECnet;
rtm->rtm_dst_len = dst_len;
rtm->rtm_src_len = 0;
rtm->rtm_tos = 0;
rtm->rtm_table = tb_id;
rtm->rtm_flags = fi->fib_flags;
rtm->rtm_scope = scope;
rtm->rtm_type = type;
rtm->rtm_protocol = fi->fib_protocol;
if (nla_put_u32(skb, RTA_TABLE, tb_id) < 0)
goto errout;
if (rtm->rtm_dst_len &&
nla_put(skb, RTA_DST, 2, dst) < 0)
goto errout;
if (fi->fib_priority &&
nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority) < 0)
goto errout;
if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
goto errout;
if (fi->fib_nhs == 1) {
if (fi->fib_nh->nh_gw &&
nla_put_le16(skb, RTA_GATEWAY, fi->fib_nh->nh_gw) < 0)
goto errout;
if
