diff options
Diffstat (limited to 'net/decnet/dn_route.c')
| -rw-r--r-- | net/decnet/dn_route.c | 1878 |
1 files changed, 1878 insertions, 0 deletions
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c new file mode 100644 index 00000000..80a3de49 --- /dev/null +++ b/net/decnet/dn_route.c @@ -0,0 +1,1878 @@ +/* + * 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 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, u32 mtu); +static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, 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 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, + .negative_advice = dn_dst_negative_advice, + .link_failure = dn_dst_link_failure, + .update_pmtu = dn_dst_update_pmtu, + .neigh_lookup = dn_dst_neigh_lookup, +}; + +static void dn_dst_destroy(struct dst_entry *dst) +{ + dst_destroy_metrics_generic(dst); +} + +static __inline__ unsigned 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)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, u32 mtu) +{ + struct neighbour *n = dst_get_neighbour_noref(dst); + 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); + } + } +} + +/* + * 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 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 neighbour *n = dst_get_neighbour_noref(dst); + + 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 (dst_get_neighbour_noref(dst) == 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: + if (net_ratelimit()) + printk(KERN_DEBUG "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) +{ + if (net_ratelimit()) { + struct dn_skb_cb *cb = DN_SKB_CB(skb); + + printk(KERN_DEBUG "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, 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 && dst_get_neighbour_noref(&rt->dst) == NULL) { + n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev); + if (IS_ERR(n)) + return PTR_ERR(n); + dst_set_neighbour(&rt->dst, 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 = init_net.loopback_dev->ifindex, + .flowidn_oif = oldflp->flowidn_oif, + }; + struct dn_route *rt = NULL; + struct net_device *dev_out = NULL, *dev; + struct neighbour *neigh = NULL; + unsigned hash; + unsigned 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, init_net.loopback_dev->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 = init_net.loopback_dev->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, 0, 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; + + dst_set_neighbour(&rt->dst, 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 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 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) { + if (net_ratelimit()) + printk(KERN_CRIT "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; + flags |= RTCF_DIRECTSRC; + 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; + flags |= RTCF_DIRECTSRC; + goto make_route; + default: + goto e_inval; + } + +make_route: + rt = dst_alloc(&dn_dst_ops, out_dev, 0, 0, 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; + + dst_set_neighbour(&rt->dst, 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 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 pid, 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; + unsigned char *b = skb_tail_pointer(skb); + long expires; + + nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags); + 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; + RTA_PUT_U32(skb, RTA_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; + RTA_PUT(skb, RTA_DST, 2, &rt->rt_daddr); + if (rt->fld.saddr) { + r->rtm_src_len = 16; + RTA_PUT(skb, RTA_SRC, 2, &rt->fld.saddr); + } + if (rt->dst.dev) + RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->dst.dev->ifindex); + /* + * Note to self - change this if input routes reverse direction when + * they deal only with inputs and not with replies like they do + * currently. + */ + RTA_PUT(skb, RTA_PREFSRC, 2, &rt->rt_local_src); + if (rt->rt_daddr != rt->rt_gateway) + RTA_PUT(skb, RTA_GATEWAY, 2, &rt->rt_gateway); + if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) + goto rtattr_failure; + expires = rt->dst.expires ? rt->dst.expires - jiffies : 0; + if (rtnl_put_cacheinfo(skb, &rt->dst, 0, 0, 0, expires, + rt->dst.error) < 0) + goto rtattr_failure; + if (dn_is_input_route(rt)) + RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fld.flowidn_iif); + + nlh->nlmsg_len = skb_tail_pointer(skb) - b; + return skb->len; + +nlmsg_failure: +rtattr_failure: + nlmsg_trim(skb, b); + return -1; +} + +/* + * 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 = alloc_skb(NLMSG_GOODSIZE, 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).pid, 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).pid); + +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; + + if (!net_eq(net, &init_net)) + return 0; + + if (NLMSG_PAYLOAD(cb->nlh, 0) < sizeof(struct rtmsg)) + return -EINVAL; + if (!(((struct rtmsg *)NLMSG_DATA(cb->nlh))->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).pid, + 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, + (int) dst_metric(&rt->dst, RTAX_RTT)); + 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); +} + |