--- /dev/null
+/*
+ * 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 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 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, 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, NULL, skb,
+ skb->dev, NULL,
+ dn_route_rx_packet);
+
+drop_it:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+static int dn_route_discard(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 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,
+ 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,
+ NULL, skb, skb->dev, NULL,
+ dn_route_discard);
+ case DN_RT_PKT_ERTH:
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
+ NULL, skb, skb->dev, NULL,
+ dn_neigh_router_hello);
+
+ case DN_RT_PKT_EEDH:
+ return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO,
+ 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 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, 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;
+#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, 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_sk(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;
+
+ 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=%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);
+ /* 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 __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, 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_sk;
+ 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;
+
+ 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 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);
+ 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, 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);
+
+ remove_proc_entry("decnet_cache", init_net.proc_net);
+ dst_entries_destroy(&dn_dst_ops);
+}
+
Code Review / kvmfornfv.git / blobdiff