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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 Neighbour Functions (Adjacency Database and
* On-Ethernet Cache)
*
* Author: Steve Whitehouse <SteveW@ACM.org>
*
*
* Changes:
* Steve Whitehouse : Fixed router listing routine
* Steve Whitehouse : Added error_report functions
* Steve Whitehouse : Added default router detection
* Steve Whitehouse : Hop counts in outgoing messages
* Steve Whitehouse : Fixed src/dst in outgoing messages so
* forwarding now stands a good chance of
* working.
* Steve Whitehouse : Fixed neighbour states (for now anyway).
* Steve Whitehouse : Made error_report functions dummies. This
* is not the right place to return skbs.
*
*/
#include <linux/config.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/string.h>
#include <linux/netfilter_decnet.h>
#include <linux/spinlock.h>
#include <asm/atomic.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_neigh.h>
#include <net/dn_route.h>
static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev);
static int dn_neigh_construct(struct neighbour *);
static void dn_long_error_report(struct neighbour *, struct sk_buff *);
static void dn_short_error_report(struct neighbour *, struct sk_buff *);
static int dn_long_output(struct sk_buff *);
static int dn_short_output(struct sk_buff *);
static int dn_phase3_output(struct sk_buff *);
/*
* For talking to broadcast devices: Ethernet & PPP
*/
static struct neigh_ops dn_long_ops = {
family: AF_DECnet,
error_report: dn_long_error_report,
output: dn_long_output,
connected_output: dn_long_output,
hh_output: dev_queue_xmit,
queue_xmit: dev_queue_xmit,
};
/*
* For talking to pointopoint and multidrop devices: DDCMP and X.25
*/
static struct neigh_ops dn_short_ops = {
family: AF_DECnet,
error_report: dn_short_error_report,
output: dn_short_output,
connected_output: dn_short_output,
hh_output: dev_queue_xmit,
queue_xmit: dev_queue_xmit,
};
/*
* For talking to DECnet phase III nodes
*/
static struct neigh_ops dn_phase3_ops = {
family: AF_DECnet,
error_report: dn_short_error_report, /* Can use short version here */
output: dn_phase3_output,
connected_output: dn_phase3_output,
hh_output: dev_queue_xmit,
queue_xmit: dev_queue_xmit
};
struct neigh_table dn_neigh_table = {
family: PF_DECnet,
entry_size: sizeof(struct dn_neigh),
key_len: sizeof(dn_address),
hash: dn_neigh_hash,
constructor: dn_neigh_construct,
id: "dn_neigh_cache",
parms: {
tbl: &dn_neigh_table,
entries: 0,
base_reachable_time: 30 * HZ,
retrans_time: 1 * HZ,
gc_staletime: 60 * HZ,
reachable_time: 30 * HZ,
delay_probe_time: 5 * HZ,
queue_len: 3,
ucast_probes: 0,
app_probes: 0,
mcast_probes: 0,
anycast_delay: 0,
proxy_delay: 0,
proxy_qlen: 0,
locktime: 1 * HZ,
},
gc_interval: 30 * HZ,
gc_thresh1: 128,
gc_thresh2: 512,
gc_thresh3: 1024,
};
static u32 dn_neigh_hash(const void *pkey, const struct net_device *dev)
{
u32 hash_val;
hash_val = *(dn_address *)pkey;
hash_val ^= (hash_val >> 10);
hash_val ^= (hash_val >> 3);
return hash_val & NEIGH_HASHMASK;
}
static int dn_neigh_construct(struct neighbour *neigh)
{
struct net_device *dev = neigh->dev;
struct dn_neigh *dn = (struct dn_neigh *)neigh;
struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
if (dn_db == NULL)
return -EINVAL;
if (dn_db->neigh_parms)
neigh->parms = dn_db->neigh_parms;
if (dn_db->use_long)
neigh->ops = &dn_long_ops;
else
neigh->ops = &dn_short_ops;
if (dn->flags & DN_NDFLAG_P3)
neigh->ops = &dn_phase3_ops;
neigh->nud_state = NUD_NOARP;
neigh->output = neigh->ops->connected_output;
if ((dev->type == ARPHRD_IPGRE) || (dev->flags & IFF_POINTOPOINT))
memcpy(neigh->ha, dev->broadcast, dev->addr_len);
else if ((dev->type == ARPHRD_ETHER) || (dev->type == ARPHRD_LOOPBACK))
dn_dn2eth(neigh->ha, dn->addr);
else {
if (net_ratelimit())
printk(KERN_DEBUG "Trying to create neigh for hw %d\n", dev->type);
return -EINVAL;
}
dn->blksize = 230;
return 0;
}
static void dn_long_error_report(struct neighbour *neigh, struct sk_buff *skb)
{
printk(KERN_DEBUG "dn_long_error_report: called\n");
kfree_skb(skb);
}
static void dn_short_error_report(struct neighbour *neigh, struct sk_buff *skb)
{
printk(KERN_DEBUG "dn_short_error_report: called\n");
kfree_skb(skb);
}
static int dn_neigh_output_packet(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
if (!dev->hard_header || dev->hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, NULL, skb->len) >= 0)
return neigh->ops->queue_xmit(skb);
if (net_ratelimit())
printk(KERN_DEBUG "dn_neigh_output_packet: oops, can't send packet\n");
kfree_skb(skb);
return -EINVAL;
}
static int dn_long_output(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_long_packet) + 3;
unsigned char *data;
struct dn_long_packet *lp;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_long_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_long_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_long_packet) + 3);
lp = (struct dn_long_packet *)(data+3);
*((unsigned short *)data) = dn_htons(skb->len - 2);
*(data + 2) = 1 | DN_RT_F_PF; /* Padding */
lp->msgflg = DN_RT_PKT_LONG|(cb->rt_flags&(DN_RT_F_IE|DN_RT_F_RQR|DN_RT_F_RTS));
lp->d_area = lp->d_subarea = 0;
dn_dn2eth(lp->d_id, dn_ntohs(cb->dst));
lp->s_area = lp->s_subarea = 0;
dn_dn2eth(lp->s_id, dn_ntohs(cb->src));
lp->nl2 = 0;
lp->visit_ct = cb->hops & 0x3f;
lp->s_class = 0;
lp->pt = 0;
skb->nh.raw = skb->data;
return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
}
static int dn_short_output(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
struct dn_short_packet *sp;
unsigned char *data;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_short_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_short_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
*((unsigned short *)data) = dn_htons(skb->len - 2);
sp = (struct dn_short_packet *)(data+2);
sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
sp->dstnode = cb->dst;
sp->srcnode = cb->src;
sp->forward = cb->hops & 0x3f;
skb->nh.raw = skb->data;
return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
}
/*
* Phase 3 output is the same is short output, execpt that
* it clears the area bits before transmission.
*/
static int dn_phase3_output(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
int headroom = dev->hard_header_len + sizeof(struct dn_short_packet) + 2;
struct dn_short_packet *sp;
unsigned char *data;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
if (skb_headroom(skb) < headroom) {
struct sk_buff *skb2 = skb_realloc_headroom(skb, headroom);
if (skb2 == NULL) {
if (net_ratelimit())
printk(KERN_CRIT "dn_phase3_output: no memory\n");
kfree_skb(skb);
return -ENOBUFS;
}
kfree_skb(skb);
skb = skb2;
if (net_ratelimit())
printk(KERN_INFO "dn_phase3_output: Increasing headroom\n");
}
data = skb_push(skb, sizeof(struct dn_short_packet) + 2);
((unsigned short *)data) = dn_htons(skb->len - 2);
sp = (struct dn_short_packet *)(data + 2);
sp->msgflg = DN_RT_PKT_SHORT|(cb->rt_flags&(DN_RT_F_RQR|DN_RT_F_RTS));
sp->dstnode = cb->dst & dn_htons(0x03ff);
sp->srcnode = cb->src & dn_htons(0x03ff);
sp->forward = cb->hops & 0x3f;
skb->nh.raw = skb->data;
return NF_HOOK(PF_DECnet, NF_DN_POST_ROUTING, skb, NULL, neigh->dev, dn_neigh_output_packet);
}
/*
* Unfortunately, the neighbour code uses the device in its hash
* function, so we don't get any advantage from it. This function
* basically does a neigh_lookup(), but without comparing the device
* field. This is required for the On-Ethernet cache
*/
struct neighbour *dn_neigh_lookup(struct neigh_table *tbl, void *ptr)
{
struct neighbour *neigh;
u32 hash_val;
hash_val = tbl->hash(ptr, NULL);
read_lock_bh(&tbl->lock);
for(neigh = tbl->hash_buckets[hash_val]; neigh != NULL; neigh = neigh->next) {
if (memcmp(neigh->primary_key, ptr, tbl->key_len) == 0) {
atomic_inc(&neigh->refcnt);
read_unlock_bh(&tbl->lock);
return neigh;
}
}
read_unlock_bh(&tbl->lock);
return NULL;
}
/*
* Any traffic on a pointopoint link causes the timer to be reset
* for the entry in the neighbour table.
*/
void dn_neigh_pointopoint_notify(struct sk_buff *skb)
{
return;
}
/*
* Pointopoint link receives a hello message
*/
void dn_neigh_pointopoint_hello(struct sk_buff *skb)
{
kfree_skb(skb);
}
/*
* Ethernet router hello message received
*/
int dn_neigh_router_hello(struct sk_buff *skb)
{
struct rtnode_hello_message *msg = (struct rtnode_hello_message *)skb->data;
struct neighbour *neigh;
struct dn_neigh *dn;
struct dn_dev *dn_db;
dn_address src;
src = dn_htons(dn_eth2dn(msg->id));
neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
dn = (struct dn_neigh *)neigh;
if (neigh) {
write_lock(&neigh->lock);
neigh->used = jiffies;
dn_db = (struct dn_dev *)neigh->dev->dn_ptr;
if (!(neigh->nud_state & NUD_PERMANENT)) {
neigh->updated = jiffies;
if (neigh->dev->type == ARPHRD_ETHER)
memcpy(neigh->ha, &skb->mac.ethernet->h_source, ETH_ALEN);
dn->blksize = dn_ntohs(msg->blksize);
dn->priority = msg->priority;
dn->flags &= ~DN_NDFLAG_P3;
switch(msg->iinfo & DN_RT_INFO_TYPE) {
case DN_RT_INFO_L1RT:
dn->flags &=~DN_NDFLAG_R2;
dn->flags |= DN_NDFLAG_R1;
break;
case DN_RT_INFO_L2RT:
dn->flags |= DN_NDFLAG_R2;
}
}
if (!dn_db->router) {
dn_db->router = neigh_clone(neigh);
} else {
if (msg->priority > ((struct dn_neigh *)dn_db->router)->priority)
neigh_release(xchg(&dn_db->router, neigh_clone(neigh)));
}
write_unlock(&neigh->lock);
neigh_release(neigh);
}
kfree_skb(skb);
return 0;
}
/*
* Endnode hello message received
*/
int dn_neigh_endnode_hello(struct sk_buff *skb)
{
struct endnode_hello_message *msg = (struct endnode_hello_message *)skb->data;
struct neighbour *neigh;
struct dn_neigh *dn;
dn_address src;
src = dn_htons(dn_eth2dn(msg->id));
neigh = __neigh_lookup(&dn_neigh_table, &src, skb->dev, 1);
dn = (struct dn_neigh *)neigh;
if (neigh) {
write_lock(&neigh->lock);
neigh->used = jiffies;
if (!(neigh->nud_state & NUD_PERMANENT)) {
neigh->updated = jiffies;
if (neigh->dev->type == ARPHRD_ETHER)
memcpy(neigh->ha, &skb->mac.ethernet->h_source, ETH_ALEN);
dn->flags &= ~(DN_NDFLAG_R1 | DN_NDFLAG_R2);
dn->blksize = dn_ntohs(msg->blksize);
dn->priority = 0;
}
write_unlock(&neigh->lock);
neigh_release(neigh);
}
kfree_skb(skb);
return 0;
}
#ifdef CONFIG_DECNET_ROUTER
static char *dn_find_slot(char *base, int max, int priority)
{
int i;
unsigned char *min = NULL;
base += 6; /* skip first id */
for(i = 0; i < max; i++) {
if (!min || (*base < *min))
min = base;
base += 7; /* find next priority */
}
if (!min)
return NULL;
return (*min < priority) ? (min - 6) : NULL;
}
int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
{
int t = 0;
int i;
struct neighbour *neigh;
struct dn_neigh *dn;
struct neigh_table *tbl = &dn_neigh_table;
unsigned char *rs = ptr;
struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
read_lock_bh(&tbl->lock);
for(i = 0; i < NEIGH_HASHMASK; i++) {
for(neigh = tbl->hash_buckets[i]; neigh != NULL; neigh = neigh->next) {
if (neigh->dev != dev)
continue;
dn = (struct dn_neigh *)neigh;
if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
continue;
if (dn_db->parms.forwarding == 1 && (dn->flags & DN_NDFLAG_R2))
continue;
if (t == n)
rs = dn_find_slot(ptr, n, dn->priority);
else
t++;
if (rs == NULL)
continue;
dn_dn2eth(rs, dn->addr);
rs += 6;
*rs = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
*rs |= dn->priority;
rs++;
}
}
read_unlock_bh(&tbl->lock);
return t;
}
#endif /* CONFIG_DECNET_ROUTER */
#ifdef CONFIG_PROC_FS
static int dn_neigh_get_info(char *buffer, char **start, off_t offset, int length)
{
int len = 0;
off_t pos = 0;
off_t begin = 0;
struct neighbour *n;
int i;
char buf[DN_ASCBUF_LEN];
len += sprintf(buffer + len, "Addr Flags State Use Blksize Dev\n");
for(i=0;i <= NEIGH_HASHMASK; i++) {
read_lock_bh(&dn_neigh_table.lock);
n = dn_neigh_table.hash_buckets[i];
for(; n != NULL; n = n->next) {
struct dn_neigh *dn = (struct dn_neigh *)n;
read_lock(&n->lock);
len += sprintf(buffer+len, "%-7s %s%s%s %02x %02d %07ld %-8s\n",
dn_addr2asc(dn_ntohs(dn->addr), buf),
(dn->flags&DN_NDFLAG_R1) ? "1" : "-",
(dn->flags&DN_NDFLAG_R2) ? "2" : "-",
(dn->flags&DN_NDFLAG_P3) ? "3" : "-",
dn->n.nud_state,
atomic_read(&dn->n.refcnt),
dn->blksize,
(dn->n.dev) ? dn->n.dev->name : "?");
read_unlock(&n->lock);
pos = begin + len;
if (pos < offset) {
len = 0;
begin = pos;
}
if (pos > offset + length) {
read_unlock_bh(&dn_neigh_table.lock);
goto done;
}
}
read_unlock_bh(&dn_neigh_table.lock);
}
done:
*start = buffer + (offset - begin);
len -= offset - begin;
if (len > length) len = length;
return len;
}
#endif
void __init dn_neigh_init(void)
{
neigh_table_init(&dn_neigh_table);
#ifdef CONFIG_PROC_FS
proc_net_create("decnet_neigh",0,dn_neigh_get_info);
#endif /* CONFIG_PROC_FS */
}
void __exit dn_neigh_cleanup(void)
{
proc_net_remove("decnet_neigh");
neigh_table_clear(&dn_neigh_table);
}
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