kernel-ark/net/decnet/dn_neigh.c
Steven Whitehouse c4ea94ab37 [DECnet]: Endian annotation and fixes for DECnet.
The typedef for dn_address has been removed in favour of using __le16
or __u16 directly as appropriate. All the DECnet header files are
updated accordingly.

The byte ordering of dn_eth2dn() and dn_dn2eth() are both changed
since just about all their callers wanted network order rather than
host order, so the conversion is now done in the functions themselves.

Several missed endianess conversions have been picked up during the
conversion process. The nh_gw field in struct dn_fib_info has been
changed from a 32 bit field to 16 bits as it ought to be.

One or two cases of using htons rather than dn_htons in the routing
code have been found and fixed.

There are still a few warnings to fix, but this patch deals with the
important cases.

Signed-off-by: Steven Whitehouse <steve@chygwyn.com>
Signed-off-by: Patrick Caulfield <patrick@tykepenguin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:42:39 -08:00

630 lines
16 KiB
C

/*
* 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.
* Steve Whitehouse : Convert to seq_file
*
*/
#include <linux/config.h>
#include <linux/net.h>
#include <linux/module.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 <linux/seq_file.h>
#include <linux/rcupdate.h>
#include <linux/jhash.h>
#include <asm/atomic.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.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(__le16),
.hash = dn_neigh_hash,
.constructor = dn_neigh_construct,
.id = "dn_neigh_cache",
.parms ={
.tbl = &dn_neigh_table,
.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)
{
return jhash_2words(*(__u16 *)pkey, 0, dn_neigh_table.hash_rnd);
}
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 neigh_parms *parms;
rcu_read_lock();
dn_db = rcu_dereference(dev->dn_ptr);
if (dn_db == NULL) {
rcu_read_unlock();
return -EINVAL;
}
parms = dn_db->neigh_parms;
if (!parms) {
rcu_read_unlock();
return -EINVAL;
}
__neigh_parms_put(neigh->parms);
neigh->parms = neigh_parms_clone(parms);
if (dn_db->use_long)
neigh->ops = &dn_long_ops;
else
neigh->ops = &dn_short_ops;
rcu_read_unlock();
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;
}
/*
* Make an estimate of the remote block size by assuming that its
* two less then the device mtu, which it true for ethernet (and
* other things which support long format headers) since there is
* an extra length field (of 16 bits) which isn't part of the
* ethernet headers and which the DECnet specs won't admit is part
* of the DECnet routing headers either.
*
* If we over estimate here its no big deal, the NSP negotiations
* will prevent us from sending packets which are too large for the
* remote node to handle. In any case this figure is normally updated
* by a hello message in most cases.
*/
dn->blksize = dev->mtu - 2;
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 dn_route *rt = (struct dn_route *)dst;
struct neighbour *neigh = dst->neighbour;
struct net_device *dev = neigh->dev;
char mac_addr[ETH_ALEN];
dn_dn2eth(mac_addr, rt->rt_local_src);
if (!dev->hard_header || dev->hard_header(skb, dev, ntohs(skb->protocol), neigh->ha, mac_addr, 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);
*((__le16 *)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, cb->dst);
lp->s_area = lp->s_subarea = 0;
dn_dn2eth(lp->s_id, 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);
*((__le16 *)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);
*((__le16 *)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
*/
/*
* 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;
__le16 src;
src = 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, &eth_hdr(skb)->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;
}
}
/* Only use routers in our area */
if ((dn_ntohs(src)>>10) == (dn_ntohs((decnet_address))>>10)) {
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;
__le16 src;
src = 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, &eth_hdr(skb)->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;
}
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;
}
struct elist_cb_state {
struct net_device *dev;
unsigned char *ptr;
unsigned char *rs;
int t, n;
};
static void neigh_elist_cb(struct neighbour *neigh, void *_info)
{
struct elist_cb_state *s = _info;
struct dn_dev *dn_db;
struct dn_neigh *dn;
if (neigh->dev != s->dev)
return;
dn = (struct dn_neigh *) neigh;
if (!(dn->flags & (DN_NDFLAG_R1|DN_NDFLAG_R2)))
return;
dn_db = (struct dn_dev *) s->dev->dn_ptr;
if (dn_db->parms.forwarding == 1 && (dn->flags & DN_NDFLAG_R2))
return;
if (s->t == s->n)
s->rs = dn_find_slot(s->ptr, s->n, dn->priority);
else
s->t++;
if (s->rs == NULL)
return;
dn_dn2eth(s->rs, dn->addr);
s->rs += 6;
*(s->rs) = neigh->nud_state & NUD_CONNECTED ? 0x80 : 0x0;
*(s->rs) |= dn->priority;
s->rs++;
}
int dn_neigh_elist(struct net_device *dev, unsigned char *ptr, int n)
{
struct elist_cb_state state;
state.dev = dev;
state.t = 0;
state.n = n;
state.ptr = ptr;
state.rs = ptr;
neigh_for_each(&dn_neigh_table, neigh_elist_cb, &state);
return state.t;
}
#ifdef CONFIG_PROC_FS
static inline void dn_neigh_format_entry(struct seq_file *seq,
struct neighbour *n)
{
struct dn_neigh *dn = (struct dn_neigh *) n;
char buf[DN_ASCBUF_LEN];
read_lock(&n->lock);
seq_printf(seq, "%-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);
}
static int dn_neigh_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "Addr Flags State Use Blksize Dev\n");
} else {
dn_neigh_format_entry(seq, v);
}
return 0;
}
static void *dn_neigh_seq_start(struct seq_file *seq, loff_t *pos)
{
return neigh_seq_start(seq, pos, &dn_neigh_table,
NEIGH_SEQ_NEIGH_ONLY);
}
static struct seq_operations dn_neigh_seq_ops = {
.start = dn_neigh_seq_start,
.next = neigh_seq_next,
.stop = neigh_seq_stop,
.show = dn_neigh_seq_show,
};
static int dn_neigh_seq_open(struct inode *inode, struct file *file)
{
struct seq_file *seq;
int rc = -ENOMEM;
struct neigh_seq_state *s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
goto out;
memset(s, 0, sizeof(*s));
rc = seq_open(file, &dn_neigh_seq_ops);
if (rc)
goto out_kfree;
seq = file->private_data;
seq->private = s;
memset(s, 0, sizeof(*s));
out:
return rc;
out_kfree:
kfree(s);
goto out;
}
static struct file_operations dn_neigh_seq_fops = {
.owner = THIS_MODULE,
.open = dn_neigh_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_private,
};
#endif
void __init dn_neigh_init(void)
{
neigh_table_init(&dn_neigh_table);
proc_net_fops_create("decnet_neigh", S_IRUGO, &dn_neigh_seq_fops);
}
void __exit dn_neigh_cleanup(void)
{
proc_net_remove("decnet_neigh");
neigh_table_clear(&dn_neigh_table);
}