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linux/net/decnet/dn_route.c
Wei Wang 0da4af00b2 ipv6: only update __use and lastusetime once per jiffy at most 
In order to not dirty the cacheline too often, we try to only update
dst->__use and dst->lastusetime at most once per jiffy.
As dst->lastusetime is only used by ipv6 garbage collector, it should
be good enough time resolution.
And __use is only used in ipv6_route_seq_show() to show how many times a
dst has been used. And as __use is not atomic_t right now, it does not
show the precise number of usage times anyway. So we think it should be
OK to only update it at most once per jiffy.

According to my latest syn flood test on a machine with intel Xeon 6th
gen processor and 2 10G mlx nics bonded together, each with 8 rx queues
on 2 NUMA nodes:
With this patch, the packet process rate increases from ~3.49Mpps to
~3.75Mpps with a 7% increase rate.

Note: dst_use() is being renamed to dst_hold_and_use() to better specify
the purpose of the function.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@googl.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:08:30 +01:00

1941 lines
47 KiB
C
Raw Blame History

/*
* 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 Functions (Endnode and Router)
*
* Authors: Steve Whitehouse <SteveW@ACM.org>
* Eduardo Marcelo Serrat <emserrat@geocities.com>
*
* Changes:
* Steve Whitehouse : Fixes to allow "intra-ethernet" and
* "return-to-sender" bits on outgoing
* packets.
* Steve Whitehouse : Timeouts for cached routes.
* Steve Whitehouse : Use dst cache for input routes too.
* Steve Whitehouse : Fixed error values in dn_send_skb.
* Steve Whitehouse : Rework routing functions to better fit
* DECnet routing design
* Alexey Kuznetsov : New SMP locking
* Steve Whitehouse : More SMP locking changes & dn_cache_dump()
* Steve Whitehouse : Prerouting NF hook, now really is prerouting.
* Fixed possible skb leak in rtnetlink funcs.
* Steve Whitehouse : Dave Miller's dynamic hash table sizing and
* Alexey Kuznetsov's finer grained locking
* from ipv4/route.c.
* Steve Whitehouse : Routing is now starting to look like a
* sensible set of code now, mainly due to
* my copying the IPv4 routing code. The
* hooks here are modified and will continue
* to evolve for a while.
* Steve Whitehouse : Real SMP at last :-) Also new netfilter
* stuff. Look out raw sockets your days
* are numbered!
* Steve Whitehouse : Added return-to-sender functions. Added
* backlog congestion level return codes.
* Steve Whitehouse : Fixed bug where routes were set up with
* no ref count on net devices.
* Steve Whitehouse : RCU for the route cache
* Steve Whitehouse : Preparations for the flow cache
* Steve Whitehouse : Prepare for nonlinear skbs
*/
/******************************************************************************
(c) 1995-1998 E.M. Serrat emserrat@geocities.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*******************************************************************************/
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/inet.h>
#include <linux/route.h>
#include <linux/in_route.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/rtnetlink.h>
#include <linux/string.h>
#include <linux/netfilter_decnet.h>
#include <linux/rcupdate.h>
#include <linux/times.h>
#include <linux/export.h>
#include <asm/errno.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_nsp.h>
#include <net/dn_route.h>
#include <net/dn_neigh.h>
#include <net/dn_fib.h>
struct dn_rt_hash_bucket
{
struct dn_route __rcu *chain;
spinlock_t lock;
};
extern struct neigh_table dn_neigh_table;
static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00};
static const int dn_rt_min_delay = 2 * HZ;
static const int dn_rt_max_delay = 10 * HZ;
static const int dn_rt_mtu_expires = 10 * 60 * HZ;
static unsigned long dn_rt_deadline;
static int dn_dst_gc(struct dst_ops *ops);
static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
static unsigned int dn_dst_mtu(const struct dst_entry *dst);
static void dn_dst_destroy(struct dst_entry *);
static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how);
static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
static void dn_dst_link_failure(struct sk_buff *);
static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
struct sk_buff *skb , u32 mtu);
static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
struct sk_buff *skb);
static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
struct sk_buff *skb,
const void *daddr);
static int dn_route_input(struct sk_buff *);
static void dn_run_flush(unsigned long dummy);
static struct dn_rt_hash_bucket *dn_rt_hash_table;
static unsigned int dn_rt_hash_mask;
static struct timer_list dn_route_timer;
static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0);
int decnet_dst_gc_interval = 2;
static struct dst_ops dn_dst_ops = {
.family = PF_DECnet,
.gc_thresh = 128,
.gc = dn_dst_gc,
.check = dn_dst_check,
.default_advmss = dn_dst_default_advmss,
.mtu = dn_dst_mtu,
.cow_metrics = dst_cow_metrics_generic,
.destroy = dn_dst_destroy,
.ifdown = dn_dst_ifdown,
.negative_advice = dn_dst_negative_advice,
.link_failure = dn_dst_link_failure,
.update_pmtu = dn_dst_update_pmtu,
.redirect = dn_dst_redirect,
.neigh_lookup = dn_dst_neigh_lookup,
};
static void dn_dst_destroy(struct dst_entry *dst)
{
struct dn_route *rt = (struct dn_route *) dst;
if (rt->n)
neigh_release(rt->n);
dst_destroy_metrics_generic(dst);
}
static void dn_dst_ifdown(struct dst_entry *dst, struct net_device *dev, int how)
{
if (how) {
struct dn_route *rt = (struct dn_route *) dst;
struct neighbour *n = rt->n;
if (n && n->dev == dev) {
n->dev = dev_net(dev)->loopback_dev;
dev_hold(n->dev);
dev_put(dev);
}
}
}
static __inline__ unsigned int dn_hash(__le16 src, __le16 dst)
{
__u16 tmp = (__u16 __force)(src ^ dst);
tmp ^= (tmp >> 3);
tmp ^= (tmp >> 5);
tmp ^= (tmp >> 10);
return dn_rt_hash_mask & (unsigned int)tmp;
}
static void dn_dst_check_expire(unsigned long dummy)
{
int i;
struct dn_route *rt;
struct dn_route __rcu **rtp;
unsigned long now = jiffies;
unsigned long expire = 120 * HZ;
for (i = 0; i <= dn_rt_hash_mask; i++) {
rtp = &dn_rt_hash_table[i].chain;
spin_lock(&dn_rt_hash_table[i].lock);
while ((rt = rcu_dereference_protected(*rtp,
lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
if (atomic_read(&rt->dst.__refcnt) > 1 ||
(now - rt->dst.lastuse) < expire) {
rtp = &rt->dst.dn_next;
continue;
}
*rtp = rt->dst.dn_next;
rt->dst.dn_next = NULL;
dst_dev_put(&rt->dst);
dst_release(&rt->dst);
}
spin_unlock(&dn_rt_hash_table[i].lock);
if ((jiffies - now) > 0)
break;
}
mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ);
}
static int dn_dst_gc(struct dst_ops *ops)
{
struct dn_route *rt;
struct dn_route __rcu **rtp;
int i;
unsigned long now = jiffies;
unsigned long expire = 10 * HZ;
for (i = 0; i <= dn_rt_hash_mask; i++) {
spin_lock_bh(&dn_rt_hash_table[i].lock);
rtp = &dn_rt_hash_table[i].chain;
while ((rt = rcu_dereference_protected(*rtp,
lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) {
if (atomic_read(&rt->dst.__refcnt) > 1 ||
(now - rt->dst.lastuse) < expire) {
rtp = &rt->dst.dn_next;
continue;
}
*rtp = rt->dst.dn_next;
rt->dst.dn_next = NULL;
dst_dev_put(&rt->dst);
dst_release(&rt->dst);
break;
}
spin_unlock_bh(&dn_rt_hash_table[i].lock);
}
return 0;
}
/*
* The decnet standards don't impose a particular minimum mtu, what they
* do insist on is that the routing layer accepts a datagram of at least
* 230 bytes long. Here we have to subtract the routing header length from
* 230 to get the minimum acceptable mtu. If there is no neighbour, then we
* assume the worst and use a long header size.
*
* We update both the mtu and the advertised mss (i.e. the segment size we
* advertise to the other end).
*/
static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk,
struct sk_buff *skb, u32 mtu)
{
struct dn_route *rt = (struct dn_route *) dst;
struct neighbour *n = rt->n;
u32 min_mtu = 230;
struct dn_dev *dn;
dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL;
if (dn && dn->use_long == 0)
min_mtu -= 6;
else
min_mtu -= 21;
if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) {
if (!(dst_metric_locked(dst, RTAX_MTU))) {
dst_metric_set(dst, RTAX_MTU, mtu);
dst_set_expires(dst, dn_rt_mtu_expires);
}
if (!(dst_metric_locked(dst, RTAX_ADVMSS))) {
u32 mss = mtu - DN_MAX_NSP_DATA_HEADER;
u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS);
if (!existing_mss || existing_mss > mss)
dst_metric_set(dst, RTAX_ADVMSS, mss);
}
}
}
static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk,
struct sk_buff *skb)
{
}
/*
* When a route has been marked obsolete. (e.g. routing cache flush)
*/
static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie)
{
return NULL;
}
static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst)
{
dst_release(dst);
return NULL;
}
static void dn_dst_link_failure(struct sk_buff *skb)
{
}
static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2)
{
return ((fl1->daddr ^ fl2->daddr) |
(fl1->saddr ^ fl2->saddr) |
(fl1->flowidn_mark ^ fl2->flowidn_mark) |
(fl1->flowidn_scope ^ fl2->flowidn_scope) |
(fl1->flowidn_oif ^ fl2->flowidn_oif) |
(fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0;
}
static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp)
{
struct dn_route *rth;
struct dn_route __rcu **rthp;
unsigned long now = jiffies;
rthp = &dn_rt_hash_table[hash].chain;
spin_lock_bh(&dn_rt_hash_table[hash].lock);
while ((rth = rcu_dereference_protected(*rthp,
lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) {
if (compare_keys(&rth->fld, &rt->fld)) {
/* Put it first */
*rthp = rth->dst.dn_next;
rcu_assign_pointer(rth->dst.dn_next,
dn_rt_hash_table[hash].chain);
rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth);
dst_hold_and_use(&rth->dst, now);
spin_unlock_bh(&dn_rt_hash_table[hash].lock);
dst_release_immediate(&rt->dst);
*rp = rth;
return 0;
}
rthp = &rth->dst.dn_next;
}
rcu_assign_pointer(rt->dst.dn_next, dn_rt_hash_table[hash].chain);
rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt);
dst_hold_and_use(&rt->dst, now);
spin_unlock_bh(&dn_rt_hash_table[hash].lock);
*rp = rt;
return 0;
}
static void dn_run_flush(unsigned long dummy)
{
int i;
struct dn_route *rt, *next;
for (i = 0; i < dn_rt_hash_mask; i++) {
spin_lock_bh(&dn_rt_hash_table[i].lock);
if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL)
goto nothing_to_declare;
for(; rt; rt = next) {
next = rcu_dereference_raw(rt->dst.dn_next);
RCU_INIT_POINTER(rt->dst.dn_next, NULL);
dst_dev_put(&rt->dst);
dst_release(&rt->dst);
}
nothing_to_declare:
spin_unlock_bh(&dn_rt_hash_table[i].lock);
}
}
static DEFINE_SPINLOCK(dn_rt_flush_lock);
void dn_rt_cache_flush(int delay)
{
unsigned long now = jiffies;
int user_mode = !in_interrupt();
if (delay < 0)
delay = dn_rt_min_delay;
spin_lock_bh(&dn_rt_flush_lock);
if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) {
long tmo = (long)(dn_rt_deadline - now);
if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay)
tmo = 0;
if (delay > tmo)
delay = tmo;
}
if (delay <= 0) {
spin_unlock_bh(&dn_rt_flush_lock);
dn_run_flush(0);
return;
}
if (dn_rt_deadline == 0)
dn_rt_deadline = now + dn_rt_max_delay;
dn_rt_flush_timer.expires = now + delay;
add_timer(&dn_rt_flush_timer);
spin_unlock_bh(&dn_rt_flush_lock);
}
/**
* dn_return_short - Return a short packet to its sender
* @skb: The packet to return
*
*/
static int dn_return_short(struct sk_buff *skb)
{
struct dn_skb_cb *cb;
unsigned char *ptr;
__le16 *src;
__le16 *dst;
/* Add back headers */
skb_push(skb, skb->data - skb_network_header(skb));
if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
return NET_RX_DROP;
cb = DN_SKB_CB(skb);
/* Skip packet length and point to flags */
ptr = skb->data + 2;
*ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
dst = (__le16 *)ptr;
ptr += 2;
src = (__le16 *)ptr;
ptr += 2;
*ptr = 0; /* Zero hop count */
swap(*src, *dst);
skb->pkt_type = PACKET_OUTGOING;
dn_rt_finish_output(skb, NULL, NULL);
return NET_RX_SUCCESS;
}
/**
* dn_return_long - Return a long packet to its sender
* @skb: The long format packet to return
*
*/
static int dn_return_long(struct sk_buff *skb)
{
struct dn_skb_cb *cb;
unsigned char *ptr;
unsigned char *src_addr, *dst_addr;
unsigned char tmp[ETH_ALEN];
/* Add back all headers */
skb_push(skb, skb->data - skb_network_header(skb));
if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL)
return NET_RX_DROP;
cb = DN_SKB_CB(skb);
/* Ignore packet length and point to flags */
ptr = skb->data + 2;
/* Skip padding */
if (*ptr & DN_RT_F_PF) {
char padlen = (*ptr & ~DN_RT_F_PF);
ptr += padlen;
}
*ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS;
ptr += 2;
dst_addr = ptr;
ptr += 8;
src_addr = ptr;
ptr += 6;
*ptr = 0; /* Zero hop count */
/* Swap source and destination */
memcpy(tmp, src_addr, ETH_ALEN);
memcpy(src_addr, dst_addr, ETH_ALEN);
memcpy(dst_addr, tmp, ETH_ALEN);
skb->pkt_type = PACKET_OUTGOING;
dn_rt_finish_output(skb, dst_addr, src_addr);
return NET_RX_SUCCESS;
}
/**
* dn_route_rx_packet - Try and find a route for an incoming packet
* @skb: The packet to find a route for
*
* Returns: result of input function if route is found, error code otherwise
*/
static int dn_route_rx_packet(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct dn_skb_cb *cb;
int err;
if ((err = dn_route_input(skb)) == 0)
return dst_input(skb);
cb = DN_SKB_CB(skb);
if (decnet_debug_level & 4) {
char *devname = skb->dev ? skb->dev->name : "???";
printk(KERN_DEBUG
"DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n",
(int)cb->rt_flags, devname, skb->len,
le16_to_cpu(cb->src), le16_to_cpu(cb->dst),
err, skb->pkt_type);
}
if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) {
switch (cb->rt_flags & DN_RT_PKT_MSK) {
case DN_RT_PKT_SHORT:
return dn_return_short(skb);
case DN_RT_PKT_LONG:
return dn_return_long(skb);
}
}
kfree_skb(skb);
return NET_RX_DROP;
}
static int dn_route_rx_long(struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
unsigned char *ptr = skb->data;
if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */
goto drop_it;
skb_pull(skb, 20);
skb_reset_transport_header(skb);
/* Destination info */
ptr += 2;
cb->dst = dn_eth2dn(ptr);
if (memcmp(ptr, dn_hiord_addr, 4) != 0)
goto drop_it;
ptr += 6;
/* Source info */
ptr += 2;
cb->src = dn_eth2dn(ptr);
if (memcmp(ptr, dn_hiord_addr, 4) != 0)
goto drop_it;
ptr += 6;
/* Other junk */
ptr++;
cb->hops = *ptr++; /* Visit Count */
return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
&init_net, NULL, skb, skb->dev, NULL,
dn_route_rx_packet);
drop_it:
kfree_skb(skb);
return NET_RX_DROP;
}
static int dn_route_rx_short(struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
unsigned char *ptr = skb->data;
if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */
goto drop_it;
skb_pull(skb, 5);
skb_reset_transport_header(skb);
cb->dst = *(__le16 *)ptr;
ptr += 2;
cb->src = *(__le16 *)ptr;
ptr += 2;
cb->hops = *ptr & 0x3f;
return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING,
&init_net, NULL, skb, skb->dev, NULL,
dn_route_rx_packet);
drop_it:
kfree_skb(skb);
return NET_RX_DROP;
}
static int dn_route_discard(struct net *net, struct sock *sk, struct sk_buff *skb)
{
/*
* I know we drop the packet here, but thats considered success in
* this case
*/
kfree_skb(skb);
return NET_RX_SUCCESS;
}
static int dn_route_ptp_hello(struct net *net, struct sock *sk, struct sk_buff *skb)
{
dn_dev_hello(skb);
dn_neigh_pointopoint_hello(skb);
return NET_RX_SUCCESS;
}
int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct dn_skb_cb *cb;
unsigned char flags = 0;
__u16 len = le16_to_cpu(*(__le16 *)skb->data);
struct dn_dev *dn = rcu_dereference(dev->dn_ptr);
unsigned char padlen = 0;
if (!net_eq(dev_net(dev), &init_net))
goto dump_it;
if (dn == NULL)
goto dump_it;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto out;
if (!pskb_may_pull(skb, 3))
goto dump_it;
skb_pull(skb, 2);
if (len > skb->len)
goto dump_it;
skb_trim(skb, len);
flags = *skb->data;
cb = DN_SKB_CB(skb);
cb->stamp = jiffies;
cb->iif = dev->ifindex;
/*
* If we have padding, remove it.
*/
if (flags & DN_RT_F_PF) {
padlen = flags & ~DN_RT_F_PF;
if (!pskb_may_pull(skb, padlen + 1))
goto dump_it;
skb_pull(skb, padlen);
flags = *skb->data;
}
skb_reset_network_header(skb);
/*
* Weed out future version DECnet
*/
if (flags & DN_RT_F_VER)
goto dump_it;
cb->rt_flags = flags;
if (decnet_debug_level & 1)
printk(KERN_DEBUG
"dn_route_rcv: got 0x%02x from %s [%d %d %d]\n",
(int)flags, (dev) ? dev->name : "???", len, skb->len,
padlen);
if (flags & DN_RT_PKT_CNTL) {
if (unlikely(skb_linearize(skb)))
goto dump_it;
switch (flags & DN_RT_CNTL_MSK) {
case DN_RT_PKT_INIT:
dn_dev_init_pkt(skb);
break;
case DN_RT_PKT_VERI:
dn_dev_veri_pkt(skb);
break;
}
if (dn->parms.state != DN_DEV_S_RU)
goto dump_it;
switch (flags & DN_RT_CNTL_MSK) {
case DN_RT_PKT_HELO:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
&init_net, NULL, skb, skb->dev, NULL,
dn_route_ptp_hello);
case DN_RT_PKT_L1RT:
case DN_RT_PKT_L2RT:
return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE,
&init_net, NULL, skb, skb->dev, NULL,
dn_route_discard);
case DN_RT_PKT_ERTH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
&init_net, NULL, skb, skb->dev, NULL,
dn_neigh_router_hello);
case DN_RT_PKT_EEDH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
&init_net, NULL, skb, skb->dev, NULL,
dn_neigh_endnode_hello);
}
} else {
if (dn->parms.state != DN_DEV_S_RU)
goto dump_it;
skb_pull(skb, 1); /* Pull flags */
switch (flags & DN_RT_PKT_MSK) {
case DN_RT_PKT_LONG:
return dn_route_rx_long(skb);
case DN_RT_PKT_SHORT:
return dn_route_rx_short(skb);
}
}
dump_it:
kfree_skb(skb);
out:
return NET_RX_DROP;
}
static int dn_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct dn_route *rt = (struct dn_route *)dst;
struct net_device *dev = dst->dev;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
int err = -EINVAL;
if (rt->n == NULL)
goto error;
skb->dev = dev;
cb->src = rt->rt_saddr;
cb->dst = rt->rt_daddr;
/*
* Always set the Intra-Ethernet bit on all outgoing packets
* originated on this node. Only valid flag from upper layers
* is return-to-sender-requested. Set hop count to 0 too.
*/
cb->rt_flags &= ~DN_RT_F_RQR;
cb->rt_flags |= DN_RT_F_IE;
cb->hops = 0;
return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT,
&init_net, sk, skb, NULL, dev,
dn_to_neigh_output);
error:
net_dbg_ratelimited("dn_output: This should not happen\n");
kfree_skb(skb);
return err;
}
static int dn_forward(struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
struct dst_entry *dst = skb_dst(skb);
struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr);
struct dn_route *rt;
int header_len;
struct net_device *dev = skb->dev;
if (skb->pkt_type != PACKET_HOST)
goto drop;
/* Ensure that we have enough space for headers */
rt = (struct dn_route *)skb_dst(skb);
header_len = dn_db->use_long ? 21 : 6;
if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len))
goto drop;
/*
* Hop count exceeded.
*/
if (++cb->hops > 30)
goto drop;
skb->dev = rt->dst.dev;
/*
* If packet goes out same interface it came in on, then set
* the Intra-Ethernet bit. This has no effect for short
* packets, so we don't need to test for them here.
*/
cb->rt_flags &= ~DN_RT_F_IE;
if (rt->rt_flags & RTCF_DOREDIRECT)
cb->rt_flags |= DN_RT_F_IE;
return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD,
&init_net, NULL, skb, dev, skb->dev,
dn_to_neigh_output);
drop:
kfree_skb(skb);
return NET_RX_DROP;
}
/*
* Used to catch bugs. This should never normally get
* called.
*/
static int dn_rt_bug_out(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
kfree_skb(skb);
return NET_RX_DROP;
}
static int dn_rt_bug(struct sk_buff *skb)
{
struct dn_skb_cb *cb = DN_SKB_CB(skb);
net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n",
le16_to_cpu(cb->src), le16_to_cpu(cb->dst));
kfree_skb(skb);
return NET_RX_DROP;
}
static unsigned int dn_dst_default_advmss(const struct dst_entry *dst)
{
return dn_mss_from_pmtu(dst->dev, dst_mtu(dst));
}
static unsigned int dn_dst_mtu(const struct dst_entry *dst)
{
unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
return mtu ? : dst->dev->mtu;
}
static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst,
struct sk_buff *skb,
const void *daddr)
{
return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev);
}
static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
{
struct dn_fib_info *fi = res->fi;
struct net_device *dev = rt->dst.dev;
unsigned int mss_metric;
struct neighbour *n;
if (fi) {
if (DN_FIB_RES_GW(*res) &&
DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
rt->rt_gateway = DN_FIB_RES_GW(*res);
dst_init_metrics(&rt->dst, fi->fib_metrics, true);
}
rt->rt_type = res->type;
if (dev != NULL && rt->n == NULL) {
n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev);
if (IS_ERR(n))
return PTR_ERR(n);
rt->n = n;
}
if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
if (mss_metric) {
unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
if (mss_metric > mss)
dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
}
return 0;
}
static inline int dn_match_addr(__le16 addr1, __le16 addr2)
{
__u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2);
int match = 16;
while(tmp) {
tmp >>= 1;
match--;
}
return match;
}
static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope)
{
__le16 saddr = 0;
struct dn_dev *dn_db;
struct dn_ifaddr *ifa;
int best_match = 0;
int ret;
rcu_read_lock();
dn_db = rcu_dereference(dev->dn_ptr);
for (ifa = rcu_dereference(dn_db->ifa_list);
ifa != NULL;
ifa = rcu_dereference(ifa->ifa_next)) {
if (ifa->ifa_scope > scope)
continue;
if (!daddr) {
saddr = ifa->ifa_local;
break;
}
ret = dn_match_addr(daddr, ifa->ifa_local);
if (ret > best_match)
saddr = ifa->ifa_local;
if (best_match == 0)
saddr = ifa->ifa_local;
}
rcu_read_unlock();
return saddr;
}
static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res)
{
return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope);
}
static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res)
{
__le16 mask = dnet_make_mask(res->prefixlen);
return (daddr&~mask)|res->fi->fib_nh->nh_gw;
}
static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard)
{
struct flowidn fld = {
.daddr = oldflp->daddr,
.saddr = oldflp->saddr,
.flowidn_scope = RT_SCOPE_UNIVERSE,
.flowidn_mark = oldflp->flowidn_mark,
.flowidn_iif = LOOPBACK_IFINDEX,
.flowidn_oif = oldflp->flowidn_oif,
};
struct dn_route *rt = NULL;
struct net_device *dev_out = NULL, *dev;
struct neighbour *neigh = NULL;
unsigned int hash;
unsigned int flags = 0;
struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
int err;
int free_res = 0;
__le16 gateway = 0;
if (decnet_debug_level & 16)
printk(KERN_DEBUG
"dn_route_output_slow: dst=%04x src=%04x mark=%d"
" iif=%d oif=%d\n", le16_to_cpu(oldflp->daddr),
le16_to_cpu(oldflp->saddr),
oldflp->flowidn_mark, LOOPBACK_IFINDEX,
oldflp->flowidn_oif);
/* If we have an output interface, verify its a DECnet device */
if (oldflp->flowidn_oif) {
dev_out = dev_get_by_index(&init_net, oldflp->flowidn_oif);
err = -ENODEV;
if (dev_out && dev_out->dn_ptr == NULL) {
dev_put(dev_out);
dev_out = NULL;
}
if (dev_out == NULL)
goto out;
}
/* If we have a source address, verify that its a local address */
if (oldflp->saddr) {
err = -EADDRNOTAVAIL;
if (dev_out) {
if (dn_dev_islocal(dev_out, oldflp->saddr))
goto source_ok;
dev_put(dev_out);
goto out;
}
rcu_read_lock();
for_each_netdev_rcu(&init_net, dev) {
if (!dev->dn_ptr)
continue;
if (!dn_dev_islocal(dev, oldflp->saddr))
continue;
if ((dev->flags & IFF_LOOPBACK) &&
oldflp->daddr &&
!dn_dev_islocal(dev, oldflp->daddr))
continue;
dev_out = dev;
break;
}
rcu_read_unlock();
if (dev_out == NULL)
goto out;
dev_hold(dev_out);
source_ok:
;
}
/* No destination? Assume its local */
if (!fld.daddr) {
fld.daddr = fld.saddr;
if (dev_out)
dev_put(dev_out);
err = -EINVAL;
dev_out = init_net.loopback_dev;
if (!dev_out->dn_ptr)
goto out;
err = -EADDRNOTAVAIL;
dev_hold(dev_out);
if (!fld.daddr) {
fld.daddr =
fld.saddr = dnet_select_source(dev_out, 0,
RT_SCOPE_HOST);
if (!fld.daddr)
goto out;
}
fld.flowidn_oif = LOOPBACK_IFINDEX;
res.type = RTN_LOCAL;
goto make_route;
}
if (decnet_debug_level & 16)
printk(KERN_DEBUG
"dn_route_output_slow: initial checks complete."
" dst=%04x src=%04x oif=%d try_hard=%d\n",
le16_to_cpu(fld.daddr), le16_to_cpu(fld.saddr),
fld.flowidn_oif, try_hard);
/*
* N.B. If the kernel is compiled without router support then
* dn_fib_lookup() will evaluate to non-zero so this if () block
* will always be executed.
*/
err = -ESRCH;
if (try_hard || (err = dn_fib_lookup(&fld, &res)) != 0) {
struct dn_dev *dn_db;
if (err != -ESRCH)
goto out;
/*
* Here the fallback is basically the standard algorithm for
* routing in endnodes which is described in the DECnet routing
* docs
*
* If we are not trying hard, look in neighbour cache.
* The result is tested to ensure that if a specific output
* device/source address was requested, then we honour that
* here
*/
if (!try_hard) {
neigh = neigh_lookup_nodev(&dn_neigh_table, &init_net, &fld.daddr);
if (neigh) {
if ((oldflp->flowidn_oif &&
(neigh->dev->ifindex != oldflp->flowidn_oif)) ||
(oldflp->saddr &&
(!dn_dev_islocal(neigh->dev,
oldflp->saddr)))) {
neigh_release(neigh);
neigh = NULL;
} else {
if (dev_out)
dev_put(dev_out);
if (dn_dev_islocal(neigh->dev, fld.daddr)) {
dev_out = init_net.loopback_dev;
res.type = RTN_LOCAL;
} else {
dev_out = neigh->dev;
}
dev_hold(dev_out);
goto select_source;
}
}
}
/* Not there? Perhaps its a local address */
if (dev_out == NULL)
dev_out = dn_dev_get_default();
err = -ENODEV;
if (dev_out == NULL)
goto out;
dn_db = rcu_dereference_raw(dev_out->dn_ptr);
if (!dn_db)
goto e_inval;
/* Possible improvement - check all devices for local addr */
if (dn_dev_islocal(dev_out, fld.daddr)) {
dev_put(dev_out);
dev_out = init_net.loopback_dev;
dev_hold(dev_out);
res.type = RTN_LOCAL;
goto select_source;
}
/* Not local either.... try sending it to the default router */
neigh = neigh_clone(dn_db->router);
BUG_ON(neigh && neigh->dev != dev_out);
/* Ok then, we assume its directly connected and move on */
select_source:
if (neigh)
gateway = ((struct dn_neigh *)neigh)->addr;
if (gateway == 0)
gateway = fld.daddr;
if (fld.saddr == 0) {
fld.saddr = dnet_select_source(dev_out, gateway,
res.type == RTN_LOCAL ?
RT_SCOPE_HOST :
RT_SCOPE_LINK);
if (fld.saddr == 0 && res.type != RTN_LOCAL)
goto e_addr;
}
fld.flowidn_oif = dev_out->ifindex;
goto make_route;
}
free_res = 1;
if (res.type == RTN_NAT)
goto e_inval;
if (res.type == RTN_LOCAL) {
if (!fld.saddr)
fld.saddr = fld.daddr;
if (dev_out)
dev_put(dev_out);
dev_out = init_net.loopback_dev;
dev_hold(dev_out);
if (!dev_out->dn_ptr)
goto e_inval;
fld.flowidn_oif = dev_out->ifindex;
if (res.fi)
dn_fib_info_put(res.fi);
res.fi = NULL;
goto make_route;
}
if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
dn_fib_select_multipath(&fld, &res);
/*
* We could add some logic to deal with default routes here and
* get rid of some of the special casing above.
*/
if (!fld.saddr)
fld.saddr = DN_FIB_RES_PREFSRC(res);
if (dev_out)
dev_put(dev_out);
dev_out = DN_FIB_RES_DEV(res);
dev_hold(dev_out);
fld.flowidn_oif = dev_out->ifindex;
gateway = DN_FIB_RES_GW(res);
make_route:
if (dev_out->flags & IFF_LOOPBACK)
flags |= RTCF_LOCAL;
rt = dst_alloc(&dn_dst_ops, dev_out, 0, DST_OBSOLETE_NONE, DST_HOST);
if (rt == NULL)
goto e_nobufs;
memset(&rt->fld, 0, sizeof(rt->fld));
rt->fld.saddr = oldflp->saddr;
rt->fld.daddr = oldflp->daddr;
rt->fld.flowidn_oif = oldflp->flowidn_oif;
rt->fld.flowidn_iif = 0;
rt->fld.flowidn_mark = oldflp->flowidn_mark;
rt->rt_saddr = fld.saddr;
rt->rt_daddr = fld.daddr;
rt->rt_gateway = gateway ? gateway : fld.daddr;
rt->rt_local_src = fld.saddr;
rt->rt_dst_map = fld.daddr;
rt->rt_src_map = fld.saddr;
rt->n = neigh;
neigh = NULL;
rt->dst.lastuse = jiffies;
rt->dst.output = dn_output;
rt->dst.input = dn_rt_bug;
rt->rt_flags = flags;
if (flags & RTCF_LOCAL)
rt->dst.input = dn_nsp_rx;
err = dn_rt_set_next_hop(rt, &res);
if (err)
goto e_neighbour;
hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
/* dn_insert_route() increments dst->__refcnt */
dn_insert_route(rt, hash, (struct dn_route **)pprt);
done:
if (neigh)
neigh_release(neigh);
if (free_res)
dn_fib_res_put(&res);
if (dev_out)
dev_put(dev_out);
out:
return err;
e_addr:
err = -EADDRNOTAVAIL;
goto done;
e_inval:
err = -EINVAL;
goto done;
e_nobufs:
err = -ENOBUFS;
goto done;
e_neighbour:
dst_release_immediate(&rt->dst);
goto e_nobufs;
}
/*
* N.B. The flags may be moved into the flowi at some future stage.
*/
static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags)
{
unsigned int hash = dn_hash(flp->saddr, flp->daddr);
struct dn_route *rt = NULL;
if (!(flags & MSG_TRYHARD)) {
rcu_read_lock_bh();
for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt;
rt = rcu_dereference_bh(rt->dst.dn_next)) {
if ((flp->daddr == rt->fld.daddr) &&
(flp->saddr == rt->fld.saddr) &&
(flp->flowidn_mark == rt->fld.flowidn_mark) &&
dn_is_output_route(rt) &&
(rt->fld.flowidn_oif == flp->flowidn_oif)) {
dst_hold_and_use(&rt->dst, jiffies);
rcu_read_unlock_bh();
*pprt = &rt->dst;
return 0;
}
}
rcu_read_unlock_bh();
}
return dn_route_output_slow(pprt, flp, flags);
}
static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags)
{
int err;
err = __dn_route_output_key(pprt, flp, flags);
if (err == 0 && flp->flowidn_proto) {
*pprt = xfrm_lookup(&init_net, *pprt,
flowidn_to_flowi(flp), NULL, 0);
if (IS_ERR(*pprt)) {
err = PTR_ERR(*pprt);
*pprt = NULL;
}
}
return err;
}
int dn_route_output_sock(struct dst_entry __rcu **pprt, struct flowidn *fl, struct sock *sk, int flags)
{
int err;
err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD);
if (err == 0 && fl->flowidn_proto) {
*pprt = xfrm_lookup(&init_net, *pprt,
flowidn_to_flowi(fl), sk, 0);
if (IS_ERR(*pprt)) {
err = PTR_ERR(*pprt);
*pprt = NULL;
}
}
return err;
}
static int dn_route_input_slow(struct sk_buff *skb)
{
struct dn_route *rt = NULL;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
struct net_device *in_dev = skb->dev;
struct net_device *out_dev = NULL;
struct dn_dev *dn_db;
struct neighbour *neigh = NULL;
unsigned int hash;
int flags = 0;
__le16 gateway = 0;
__le16 local_src = 0;
struct flowidn fld = {
.daddr = cb->dst,
.saddr = cb->src,
.flowidn_scope = RT_SCOPE_UNIVERSE,
.flowidn_mark = skb->mark,
.flowidn_iif = skb->dev->ifindex,
};
struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE };
int err = -EINVAL;
int free_res = 0;
dev_hold(in_dev);
if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL)
goto out;
/* Zero source addresses are not allowed */
if (fld.saddr == 0)
goto out;
/*
* In this case we've just received a packet from a source
* outside ourselves pretending to come from us. We don't
* allow it any further to prevent routing loops, spoofing and
* other nasties. Loopback packets already have the dst attached
* so this only affects packets which have originated elsewhere.
*/
err = -ENOTUNIQ;
if (dn_dev_islocal(in_dev, cb->src))
goto out;
err = dn_fib_lookup(&fld, &res);
if (err) {
if (err != -ESRCH)
goto out;
/*
* Is the destination us ?
*/
if (!dn_dev_islocal(in_dev, cb->dst))
goto e_inval;
res.type = RTN_LOCAL;
} else {
__le16 src_map = fld.saddr;
free_res = 1;
out_dev = DN_FIB_RES_DEV(res);
if (out_dev == NULL) {
net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n");
goto e_inval;
}
dev_hold(out_dev);
if (res.r)
src_map = fld.saddr; /* no NAT support for now */
gateway = DN_FIB_RES_GW(res);
if (res.type == RTN_NAT) {
fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res);
dn_fib_res_put(&res);
free_res = 0;
if (dn_fib_lookup(&fld, &res))
goto e_inval;
free_res = 1;
if (res.type != RTN_UNICAST)
goto e_inval;
flags |= RTCF_DNAT;
gateway = fld.daddr;
}
fld.saddr = src_map;
}
switch(res.type) {
case RTN_UNICAST:
/*
* Forwarding check here, we only check for forwarding
* being turned off, if you want to only forward intra
* area, its up to you to set the routing tables up
* correctly.
*/
if (dn_db->parms.forwarding == 0)
goto e_inval;
if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0)
dn_fib_select_multipath(&fld, &res);
/*
* Check for out_dev == in_dev. We use the RTCF_DOREDIRECT
* flag as a hint to set the intra-ethernet bit when
* forwarding. If we've got NAT in operation, we don't do
* this optimisation.
*/
if (out_dev == in_dev && !(flags & RTCF_NAT))
flags |= RTCF_DOREDIRECT;
local_src = DN_FIB_RES_PREFSRC(res);
case RTN_BLACKHOLE:
case RTN_UNREACHABLE:
break;
case RTN_LOCAL:
flags |= RTCF_LOCAL;
fld.saddr = cb->dst;
fld.daddr = cb->src;
/* Routing tables gave us a gateway */
if (gateway)
goto make_route;
/* Packet was intra-ethernet, so we know its on-link */
if (cb->rt_flags & DN_RT_F_IE) {
gateway = cb->src;
goto make_route;
}
/* Use the default router if there is one */
neigh = neigh_clone(dn_db->router);
if (neigh) {
gateway = ((struct dn_neigh *)neigh)->addr;
goto make_route;
}
/* Close eyes and pray */
gateway = cb->src;
goto make_route;
default:
goto e_inval;
}
make_route:
rt = dst_alloc(&dn_dst_ops, out_dev, 1, DST_OBSOLETE_NONE, DST_HOST);
if (rt == NULL)
goto e_nobufs;
memset(&rt->fld, 0, sizeof(rt->fld));
rt->rt_saddr = fld.saddr;
rt->rt_daddr = fld.daddr;
rt->rt_gateway = fld.daddr;
if (gateway)
rt->rt_gateway = gateway;
rt->rt_local_src = local_src ? local_src : rt->rt_saddr;
rt->rt_dst_map = fld.daddr;
rt->rt_src_map = fld.saddr;
rt->fld.saddr = cb->src;
rt->fld.daddr = cb->dst;
rt->fld.flowidn_oif = 0;
rt->fld.flowidn_iif = in_dev->ifindex;
rt->fld.flowidn_mark = fld.flowidn_mark;
rt->n = neigh;
rt->dst.lastuse = jiffies;
rt->dst.output = dn_rt_bug_out;
switch (res.type) {
case RTN_UNICAST:
rt->dst.input = dn_forward;
break;
case RTN_LOCAL:
rt->dst.output = dn_output;
rt->dst.input = dn_nsp_rx;
rt->dst.dev = in_dev;
flags |= RTCF_LOCAL;
break;
default:
case RTN_UNREACHABLE:
case RTN_BLACKHOLE:
rt->dst.input = dst_discard;
}
rt->rt_flags = flags;
err = dn_rt_set_next_hop(rt, &res);
if (err)
goto e_neighbour;
hash = dn_hash(rt->fld.saddr, rt->fld.daddr);
/* dn_insert_route() increments dst->__refcnt */
dn_insert_route(rt, hash, &rt);
skb_dst_set(skb, &rt->dst);
done:
if (neigh)
neigh_release(neigh);
if (free_res)
dn_fib_res_put(&res);
dev_put(in_dev);
if (out_dev)
dev_put(out_dev);
out:
return err;
e_inval:
err = -EINVAL;
goto done;
e_nobufs:
err = -ENOBUFS;
goto done;
e_neighbour:
dst_release_immediate(&rt->dst);
goto done;
}
static int dn_route_input(struct sk_buff *skb)
{
struct dn_route *rt;
struct dn_skb_cb *cb = DN_SKB_CB(skb);
unsigned int hash = dn_hash(cb->src, cb->dst);
if (skb_dst(skb))
return 0;
rcu_read_lock();
for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL;
rt = rcu_dereference(rt->dst.dn_next)) {
if ((rt->fld.saddr == cb->src) &&
(rt->fld.daddr == cb->dst) &&
(rt->fld.flowidn_oif == 0) &&
(rt->fld.flowidn_mark == skb->mark) &&
(rt->fld.flowidn_iif == cb->iif)) {
dst_hold_and_use(&rt->dst, jiffies);
rcu_read_unlock();
skb_dst_set(skb, (struct dst_entry *)rt);
return 0;
}
}
rcu_read_unlock();
return dn_route_input_slow(skb);
}
static int dn_rt_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
int event, int nowait, unsigned int flags)
{
struct dn_route *rt = (struct dn_route *)skb_dst(skb);
struct rtmsg *r;
struct nlmsghdr *nlh;
long expires;
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*r), flags);
if (!nlh)
return -EMSGSIZE;
r = nlmsg_data(nlh);
r->rtm_family = AF_DECnet;
r->rtm_dst_len = 16;
r->rtm_src_len = 0;
r->rtm_tos = 0;
r->rtm_table = RT_TABLE_MAIN;
r->rtm_type = rt->rt_type;
r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
r->rtm_scope = RT_SCOPE_UNIVERSE;
r->rtm_protocol = RTPROT_UNSPEC;
if (rt->rt_flags & RTCF_NOTIFY)
r->rtm_flags |= RTM_F_NOTIFY;
if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 ||
nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0)
goto errout;
if (rt->fld.saddr) {
r->rtm_src_len = 16;
if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0)
goto errout;
}
if (rt->dst.dev &&
nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0)
goto errout;
/*
* Note to self - change this if input routes reverse direction when
* they deal only with inputs and not with replies like they do
* currently.
*/
if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0)
goto errout;
if (rt->rt_daddr != rt->rt_gateway &&
nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0)
goto errout;
if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
goto errout;
expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires,
rt->dst.error) < 0)
goto errout;
if (dn_is_input_route(rt) &&
nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0)
goto errout;
nlmsg_end(skb, nlh);
return 0;
errout:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
const struct nla_policy rtm_dn_policy[RTA_MAX + 1] = {
[RTA_DST] = { .type = NLA_U16 },
[RTA_SRC] = { .type = NLA_U16 },
[RTA_IIF] = { .type = NLA_U32 },
[RTA_OIF] = { .type = NLA_U32 },
[RTA_GATEWAY] = { .type = NLA_U16 },
[RTA_PRIORITY] = { .type = NLA_U32 },
[RTA_PREFSRC] = { .type = NLA_U16 },
[RTA_METRICS] = { .type = NLA_NESTED },
[RTA_MULTIPATH] = { .type = NLA_NESTED },
[RTA_TABLE] = { .type = NLA_U32 },
[RTA_MARK] = { .type = NLA_U32 },
};
/*
* This is called by both endnodes and routers now.
*/
static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct net *net = sock_net(in_skb->sk);
struct rtmsg *rtm = nlmsg_data(nlh);
struct dn_route *rt = NULL;
struct dn_skb_cb *cb;
int err;
struct sk_buff *skb;
struct flowidn fld;
struct nlattr *tb[RTA_MAX+1];
if (!net_eq(net, &init_net))
return -EINVAL;
err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_dn_policy,
extack);
if (err < 0)
return err;
memset(&fld, 0, sizeof(fld));
fld.flowidn_proto = DNPROTO_NSP;
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (skb == NULL)
return -ENOBUFS;
skb_reset_mac_header(skb);
cb = DN_SKB_CB(skb);
if (tb[RTA_SRC])
fld.saddr = nla_get_le16(tb[RTA_SRC]);
if (tb[RTA_DST])
fld.daddr = nla_get_le16(tb[RTA_DST]);
if (tb[RTA_IIF])
fld.flowidn_iif = nla_get_u32(tb[RTA_IIF]);
if (fld.flowidn_iif) {
struct net_device *dev;
dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
if (!dev || !dev->dn_ptr) {
kfree_skb(skb);
return -ENODEV;
}
skb->protocol = htons(ETH_P_DNA_RT);
skb->dev = dev;
cb->src = fld.saddr;
cb->dst = fld.daddr;
local_bh_disable();
err = dn_route_input(skb);
local_bh_enable();
memset(cb, 0, sizeof(struct dn_skb_cb));
rt = (struct dn_route *)skb_dst(skb);
if (!err && -rt->dst.error)
err = rt->dst.error;
} else {
if (tb[RTA_OIF])
fld.flowidn_oif = nla_get_u32(tb[RTA_OIF]);
err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
}
skb->dev = NULL;
if (err)
goto out_free;
skb_dst_set(skb, &rt->dst);
if (rtm->rtm_flags & RTM_F_NOTIFY)
rt->rt_flags |= RTCF_NOTIFY;
err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, RTM_NEWROUTE, 0, 0);
if (err < 0) {
err = -EMSGSIZE;
goto out_free;
}
return rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).portid);
out_free:
kfree_skb(skb);
return err;
}
/*
* For routers, this is called from dn_fib_dump, but for endnodes its
* called directly from the rtnetlink dispatch table.
*/
int dn_cache_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
struct dn_route *rt;
int h, s_h;
int idx, s_idx;
struct rtmsg *rtm;
if (!net_eq(net, &init_net))
return 0;
if (nlmsg_len(cb->nlh) < sizeof(struct rtmsg))
return -EINVAL;
rtm = nlmsg_data(cb->nlh);
if (!(rtm->rtm_flags & RTM_F_CLONED))
return 0;
s_h = cb->args[0];
s_idx = idx = cb->args[1];
for(h = 0; h <= dn_rt_hash_mask; h++) {
if (h < s_h)
continue;
if (h > s_h)
s_idx = 0;
rcu_read_lock_bh();
for(rt = rcu_dereference_bh(dn_rt_hash_table[h].chain), idx = 0;
rt;
rt = rcu_dereference_bh(rt->dst.dn_next), idx++) {
if (idx < s_idx)
continue;
skb_dst_set(skb, dst_clone(&rt->dst));
if (dn_rt_fill_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, RTM_NEWROUTE,
1, NLM_F_MULTI) < 0) {
skb_dst_drop(skb);
rcu_read_unlock_bh();
goto done;
}
skb_dst_drop(skb);
}
rcu_read_unlock_bh();
}
done:
cb->args[0] = h;
cb->args[1] = idx;
return skb->len;
}
#ifdef CONFIG_PROC_FS
struct dn_rt_cache_iter_state {
int bucket;
};
static struct dn_route *dn_rt_cache_get_first(struct seq_file *seq)
{
struct dn_route *rt = NULL;
struct dn_rt_cache_iter_state *s = seq->private;
for(s->bucket = dn_rt_hash_mask; s->bucket >= 0; --s->bucket) {
rcu_read_lock_bh();
rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
if (rt)
break;
rcu_read_unlock_bh();
}
return rt;
}
static struct dn_route *dn_rt_cache_get_next(struct seq_file *seq, struct dn_route *rt)
{
struct dn_rt_cache_iter_state *s = seq->private;
rt = rcu_dereference_bh(rt->dst.dn_next);
while (!rt) {
rcu_read_unlock_bh();
if (--s->bucket < 0)
break;
rcu_read_lock_bh();
rt = rcu_dereference_bh(dn_rt_hash_table[s->bucket].chain);
}
return rt;
}
static void *dn_rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
{
struct dn_route *rt = dn_rt_cache_get_first(seq);
if (rt) {
while(*pos && (rt = dn_rt_cache_get_next(seq, rt)))
--*pos;
}
return *pos ? NULL : rt;
}
static void *dn_rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct dn_route *rt = dn_rt_cache_get_next(seq, v);
++*pos;
return rt;
}
static void dn_rt_cache_seq_stop(struct seq_file *seq, void *v)
{
if (v)
rcu_read_unlock_bh();
}
static int dn_rt_cache_seq_show(struct seq_file *seq, void *v)
{
struct dn_route *rt = v;
char buf1[DN_ASCBUF_LEN], buf2[DN_ASCBUF_LEN];
seq_printf(seq, "%-8s %-7s %-7s %04d %04d %04d\n",
rt->dst.dev ? rt->dst.dev->name : "*",
dn_addr2asc(le16_to_cpu(rt->rt_daddr), buf1),
dn_addr2asc(le16_to_cpu(rt->rt_saddr), buf2),
atomic_read(&rt->dst.__refcnt),
rt->dst.__use, 0);
return 0;
}
static const struct seq_operations dn_rt_cache_seq_ops = {
.start = dn_rt_cache_seq_start,
.next = dn_rt_cache_seq_next,
.stop = dn_rt_cache_seq_stop,
.show = dn_rt_cache_seq_show,
};
static int dn_rt_cache_seq_open(struct inode *inode, struct file *file)
{
return seq_open_private(file, &dn_rt_cache_seq_ops,
sizeof(struct dn_rt_cache_iter_state));
}
static const struct file_operations dn_rt_cache_seq_fops = {
.owner = THIS_MODULE,
.open = dn_rt_cache_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_private,
};
#endif /* CONFIG_PROC_FS */
void __init dn_route_init(void)
{
int i, goal, order;
dn_dst_ops.kmem_cachep =
kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0,
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
dst_entries_init(&dn_dst_ops);
setup_timer(&dn_route_timer, dn_dst_check_expire, 0);
dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
add_timer(&dn_route_timer);
goal = totalram_pages >> (26 - PAGE_SHIFT);
for(order = 0; (1UL << order) < goal; order++)
/* NOTHING */;
/*
* Only want 1024 entries max, since the table is very, very unlikely
* to be larger than that.
*/
while(order && ((((1UL << order) * PAGE_SIZE) /
sizeof(struct dn_rt_hash_bucket)) >= 2048))
order--;
do {
dn_rt_hash_mask = (1UL << order) * PAGE_SIZE /
sizeof(struct dn_rt_hash_bucket);
while(dn_rt_hash_mask & (dn_rt_hash_mask - 1))
dn_rt_hash_mask--;
dn_rt_hash_table = (struct dn_rt_hash_bucket *)
__get_free_pages(GFP_ATOMIC, order);
} while (dn_rt_hash_table == NULL && --order > 0);
if (!dn_rt_hash_table)
panic("Failed to allocate DECnet route cache hash table\n");
printk(KERN_INFO
"DECnet: Routing cache hash table of %u buckets, %ldKbytes\n",
dn_rt_hash_mask,
(long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024);
dn_rt_hash_mask--;
for(i = 0; i <= dn_rt_hash_mask; i++) {
spin_lock_init(&dn_rt_hash_table[i].lock);
dn_rt_hash_table[i].chain = NULL;
}
dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1);
proc_create("decnet_cache", S_IRUGO, init_net.proc_net,
&dn_rt_cache_seq_fops);
#ifdef CONFIG_DECNET_ROUTER
rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
dn_fib_dump, 0);
#else
rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
dn_cache_dump, 0);
#endif
}
void __exit dn_route_cleanup(void)
{
del_timer(&dn_route_timer);
dn_run_flush(0);
remove_proc_entry("decnet_cache", init_net.proc_net);
dst_entries_destroy(&dn_dst_ops);
}
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