diff options
Diffstat (limited to 'net/decnet/dn_route.c')
| -rw-r--r-- | net/decnet/dn_route.c | 1922 |
1 files changed, 0 insertions, 1922 deletions
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c deleted file mode 100644 index ac2ee1689111..000000000000 --- a/net/decnet/dn_route.c +++ /dev/null @@ -1,1922 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * 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 - -*******************************************************************************/ - -#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, - bool confirm_neigh); -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(struct timer_list *unused); - -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); -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 = blackhole_netdev; - 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(struct timer_list *unused) -{ - 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->dn_next; - continue; - } - *rtp = rt->dn_next; - rt->dn_next = NULL; - dst_dev_put(&rt->dst); - dst_release(&rt->dst); - } - spin_unlock(&dn_rt_hash_table[i].lock); - - if (jiffies != now) - 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->dn_next; - continue; - } - *rtp = rt->dn_next; - rt->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, - bool confirm_neigh) -{ - 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->dn_next; - rcu_assign_pointer(rth->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->dn_next; - } - - rcu_assign_pointer(rt->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(struct timer_list *unused) -{ - 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); - - rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL); - if (!rt) - goto nothing_to_declare; - - for (; rt; rt = next) { - next = rcu_dereference_raw(rt->dn_next); - RCU_INIT_POINTER(rt->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(NULL); - 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)); - - skb = skb_unshare(skb, GFP_ATOMIC); - if (!skb) - 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)); - - skb = skb_unshare(skb, GFP_ATOMIC); - if (!skb) - 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 - * @net: The applicable net namespace - * @sk: Socket packet transmitted on - * @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; - - err = dn_route_input(skb); - if (err == 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 that's 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; - - skb = skb_share_check(skb, GFP_ATOMIC); - if (!skb) - 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->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; - - 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 done; - } - 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 { - 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 = container_of(neigh, struct dn_neigh, n)->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; - 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); - - 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); - |