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WSL2-Linux-Kernel/net/decnet/dn_route.c

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47 KiB
C
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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 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,
.protocol = cpu_to_be16(ETH_P_DNA_RT),
.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 inline void dnrt_free(struct dn_route *rt)
{
call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
}
static inline void dnrt_drop(struct dn_route *rt)
{
dst_release(&rt->dst);
call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
}
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) ||
(now - rt->dst.lastuse) < expire) {
rtp = &rt->dst.dn_next;
continue;
}
*rtp = rt->dst.dn_next;
rt->dst.dn_next = NULL;
dnrt_free(rt);
}
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) ||
(now - rt->dst.lastuse) < expire) {
rtp = &rt->dst.dn_next;
continue;
}
*rtp = rt->dst.dn_next;
rt->dst.dn_next = NULL;
dnrt_drop(rt);
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_use(&rth->dst, now);
spin_unlock_bh(&dn_rt_hash_table[hash].lock);
dnrt_drop(rt);
*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_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_free((struct dst_entry *)rt);
}
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 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, 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, skb, skb->dev, NULL,
dn_route_rx_packet);
drop_it:
kfree_skb(skb);
return NET_RX_DROP;
}
static int dn_route_discard(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 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,
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,
skb, skb->dev, NULL,
dn_route_discard);
case DN_RT_PKT_ERTH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
skb, skb->dev, NULL,
dn_neigh_router_hello);
case DN_RT_PKT_EEDH:
return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
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_to_neigh_output(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
struct dn_route *rt = (struct dn_route *) dst;
struct neighbour *n = rt->n;
return n->output(n, skb);
}
static int dn_output(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, 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;
#ifdef CONFIG_NETFILTER
struct net_device *dev = skb->dev;
#endif
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, 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(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;
err = -EADDRNOTAVAIL;
if (dev_out)
dev_put(dev_out);
dev_out = init_net.loopback_dev;
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=%o4x 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);
/* 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);
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, 1, 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(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_free(&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_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 **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) {
if (!(flags & MSG_DONTWAIT))
fl->flowidn_flags |= FLOWI_FLAG_CAN_SLEEP;
*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, 0, 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;
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(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_free(&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_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;
return nlmsg_end(skb, nlh);
errout:
nlmsg_cancel(skb, nlh);
return -EMSGSIZE;
}
/*
* This is called by both endnodes and routers now.
*/
static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
{
struct net *net = sock_net(in_skb->sk);
struct rtattr **rta = arg;
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;
if (!net_eq(net, &init_net))
return -EINVAL;
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 (rta[RTA_SRC-1])
memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2);
if (rta[RTA_DST-1])
memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2);
if (rta[RTA_IIF-1])
memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int));
if (fld.flowidn_iif) {
struct net_device *dev;
if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) {
kfree_skb(skb);
return -ENODEV;
}
if (!dev->dn_ptr) {
dev_put(dev);
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 {
int oif = 0;
if (rta[RTA_OIF - 1])
memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int));
fld.flowidn_oif = oif;
err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
}
if (skb->dev)
dev_put(skb->dev);
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)
goto out_free;
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_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops);
#ifdef CONFIG_DECNET_ROUTER
rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
dn_fib_dump, NULL);
#else
rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute,
dn_cache_dump, NULL);
#endif
}
void __exit dn_route_cleanup(void)
{
del_timer(&dn_route_timer);
dn_run_flush(0);
proc_net_remove(&init_net, "decnet_cache");
dst_entries_destroy(&dn_dst_ops);
}
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