/* * 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 * Eduardo Marcelo Serrat * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct dn_rt_hash_bucket { struct dn_route __rcu *chain; spinlock_t lock; }; extern struct neigh_table dn_neigh_table; static unsigned char dn_hiord_addr[6] = {0xAA,0x00,0x04,0x00,0x00,0x00}; static const int dn_rt_min_delay = 2 * HZ; static const int dn_rt_max_delay = 10 * HZ; static const int dn_rt_mtu_expires = 10 * 60 * HZ; static unsigned long dn_rt_deadline; static int dn_dst_gc(struct dst_ops *ops); static struct dst_entry *dn_dst_check(struct dst_entry *, __u32); static unsigned int dn_dst_default_advmss(const struct dst_entry *dst); static unsigned int dn_dst_mtu(const struct dst_entry *dst); static void dn_dst_destroy(struct dst_entry *); static void dn_dst_ifdown(struct dst_entry *, struct net_device *dev, int how); static struct dst_entry *dn_dst_negative_advice(struct dst_entry *); static void dn_dst_link_failure(struct sk_buff *); static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb , u32 mtu); static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb); static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, struct sk_buff *skb, const void *daddr); static int dn_route_input(struct sk_buff *); static void dn_run_flush(unsigned long dummy); static struct dn_rt_hash_bucket *dn_rt_hash_table; static unsigned int dn_rt_hash_mask; static struct timer_list dn_route_timer; static DEFINE_TIMER(dn_rt_flush_timer, dn_run_flush, 0, 0); int decnet_dst_gc_interval = 2; static struct dst_ops dn_dst_ops = { .family = PF_DECnet, .protocol = cpu_to_be16(ETH_P_DNA_RT), .gc_thresh = 128, .gc = dn_dst_gc, .check = dn_dst_check, .default_advmss = dn_dst_default_advmss, .mtu = dn_dst_mtu, .cow_metrics = dst_cow_metrics_generic, .destroy = dn_dst_destroy, .ifdown = dn_dst_ifdown, .negative_advice = dn_dst_negative_advice, .link_failure = dn_dst_link_failure, .update_pmtu = dn_dst_update_pmtu, .redirect = dn_dst_redirect, .neigh_lookup = dn_dst_neigh_lookup, }; static void dn_dst_destroy(struct dst_entry *dst) { struct dn_route *rt = (struct dn_route *) dst; if (rt->n) neigh_release(rt->n); dst_destroy_metrics_generic(dst); } static void dn_dst_ifdown(struct dst_entry *dst, struct net_device *dev, int how) { if (how) { struct dn_route *rt = (struct dn_route *) dst; struct neighbour *n = rt->n; if (n && n->dev == dev) { n->dev = dev_net(dev)->loopback_dev; dev_hold(n->dev); dev_put(dev); } } } static __inline__ unsigned int dn_hash(__le16 src, __le16 dst) { __u16 tmp = (__u16 __force)(src ^ dst); tmp ^= (tmp >> 3); tmp ^= (tmp >> 5); tmp ^= (tmp >> 10); return dn_rt_hash_mask & (unsigned int)tmp; } static inline void dst_rcu_free(struct rcu_head *head) { struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head); dst_free(dst); } static inline void dnrt_free(struct dn_route *rt) { call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); } static inline void dnrt_drop(struct dn_route *rt) { dst_release(&rt->dst); call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); } static void dn_dst_check_expire(unsigned long dummy) { int i; struct dn_route *rt; struct dn_route __rcu **rtp; unsigned long now = jiffies; unsigned long expire = 120 * HZ; for (i = 0; i <= dn_rt_hash_mask; i++) { rtp = &dn_rt_hash_table[i].chain; spin_lock(&dn_rt_hash_table[i].lock); while ((rt = rcu_dereference_protected(*rtp, lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) { if (atomic_read(&rt->dst.__refcnt) || (now - rt->dst.lastuse) < expire) { rtp = &rt->dst.dn_next; continue; } *rtp = rt->dst.dn_next; rt->dst.dn_next = NULL; dnrt_free(rt); } spin_unlock(&dn_rt_hash_table[i].lock); if ((jiffies - now) > 0) break; } mod_timer(&dn_route_timer, now + decnet_dst_gc_interval * HZ); } static int dn_dst_gc(struct dst_ops *ops) { struct dn_route *rt; struct dn_route __rcu **rtp; int i; unsigned long now = jiffies; unsigned long expire = 10 * HZ; for (i = 0; i <= dn_rt_hash_mask; i++) { spin_lock_bh(&dn_rt_hash_table[i].lock); rtp = &dn_rt_hash_table[i].chain; while ((rt = rcu_dereference_protected(*rtp, lockdep_is_held(&dn_rt_hash_table[i].lock))) != NULL) { if (atomic_read(&rt->dst.__refcnt) || (now - rt->dst.lastuse) < expire) { rtp = &rt->dst.dn_next; continue; } *rtp = rt->dst.dn_next; rt->dst.dn_next = NULL; dnrt_drop(rt); break; } spin_unlock_bh(&dn_rt_hash_table[i].lock); } return 0; } /* * The decnet standards don't impose a particular minimum mtu, what they * do insist on is that the routing layer accepts a datagram of at least * 230 bytes long. Here we have to subtract the routing header length from * 230 to get the minimum acceptable mtu. If there is no neighbour, then we * assume the worst and use a long header size. * * We update both the mtu and the advertised mss (i.e. the segment size we * advertise to the other end). */ static void dn_dst_update_pmtu(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb, u32 mtu) { struct dn_route *rt = (struct dn_route *) dst; struct neighbour *n = rt->n; u32 min_mtu = 230; struct dn_dev *dn; dn = n ? rcu_dereference_raw(n->dev->dn_ptr) : NULL; if (dn && dn->use_long == 0) min_mtu -= 6; else min_mtu -= 21; if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= min_mtu) { if (!(dst_metric_locked(dst, RTAX_MTU))) { dst_metric_set(dst, RTAX_MTU, mtu); dst_set_expires(dst, dn_rt_mtu_expires); } if (!(dst_metric_locked(dst, RTAX_ADVMSS))) { u32 mss = mtu - DN_MAX_NSP_DATA_HEADER; u32 existing_mss = dst_metric_raw(dst, RTAX_ADVMSS); if (!existing_mss || existing_mss > mss) dst_metric_set(dst, RTAX_ADVMSS, mss); } } } static void dn_dst_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) { } /* * When a route has been marked obsolete. (e.g. routing cache flush) */ static struct dst_entry *dn_dst_check(struct dst_entry *dst, __u32 cookie) { return NULL; } static struct dst_entry *dn_dst_negative_advice(struct dst_entry *dst) { dst_release(dst); return NULL; } static void dn_dst_link_failure(struct sk_buff *skb) { } static inline int compare_keys(struct flowidn *fl1, struct flowidn *fl2) { return ((fl1->daddr ^ fl2->daddr) | (fl1->saddr ^ fl2->saddr) | (fl1->flowidn_mark ^ fl2->flowidn_mark) | (fl1->flowidn_scope ^ fl2->flowidn_scope) | (fl1->flowidn_oif ^ fl2->flowidn_oif) | (fl1->flowidn_iif ^ fl2->flowidn_iif)) == 0; } static int dn_insert_route(struct dn_route *rt, unsigned int hash, struct dn_route **rp) { struct dn_route *rth; struct dn_route __rcu **rthp; unsigned long now = jiffies; rthp = &dn_rt_hash_table[hash].chain; spin_lock_bh(&dn_rt_hash_table[hash].lock); while ((rth = rcu_dereference_protected(*rthp, lockdep_is_held(&dn_rt_hash_table[hash].lock))) != NULL) { if (compare_keys(&rth->fld, &rt->fld)) { /* Put it first */ *rthp = rth->dst.dn_next; rcu_assign_pointer(rth->dst.dn_next, dn_rt_hash_table[hash].chain); rcu_assign_pointer(dn_rt_hash_table[hash].chain, rth); dst_use(&rth->dst, now); spin_unlock_bh(&dn_rt_hash_table[hash].lock); dnrt_drop(rt); *rp = rth; return 0; } rthp = &rth->dst.dn_next; } rcu_assign_pointer(rt->dst.dn_next, dn_rt_hash_table[hash].chain); rcu_assign_pointer(dn_rt_hash_table[hash].chain, rt); dst_use(&rt->dst, now); spin_unlock_bh(&dn_rt_hash_table[hash].lock); *rp = rt; return 0; } static void dn_run_flush(unsigned long dummy) { int i; struct dn_route *rt, *next; for (i = 0; i < dn_rt_hash_mask; i++) { spin_lock_bh(&dn_rt_hash_table[i].lock); if ((rt = xchg((struct dn_route **)&dn_rt_hash_table[i].chain, NULL)) == NULL) goto nothing_to_declare; for(; rt; rt = next) { next = rcu_dereference_raw(rt->dst.dn_next); RCU_INIT_POINTER(rt->dst.dn_next, NULL); dst_free((struct dst_entry *)rt); } nothing_to_declare: spin_unlock_bh(&dn_rt_hash_table[i].lock); } } static DEFINE_SPINLOCK(dn_rt_flush_lock); void dn_rt_cache_flush(int delay) { unsigned long now = jiffies; int user_mode = !in_interrupt(); if (delay < 0) delay = dn_rt_min_delay; spin_lock_bh(&dn_rt_flush_lock); if (del_timer(&dn_rt_flush_timer) && delay > 0 && dn_rt_deadline) { long tmo = (long)(dn_rt_deadline - now); if (user_mode && tmo < dn_rt_max_delay - dn_rt_min_delay) tmo = 0; if (delay > tmo) delay = tmo; } if (delay <= 0) { spin_unlock_bh(&dn_rt_flush_lock); dn_run_flush(0); return; } if (dn_rt_deadline == 0) dn_rt_deadline = now + dn_rt_max_delay; dn_rt_flush_timer.expires = now + delay; add_timer(&dn_rt_flush_timer); spin_unlock_bh(&dn_rt_flush_lock); } /** * dn_return_short - Return a short packet to its sender * @skb: The packet to return * */ static int dn_return_short(struct sk_buff *skb) { struct dn_skb_cb *cb; unsigned char *ptr; __le16 *src; __le16 *dst; /* Add back headers */ skb_push(skb, skb->data - skb_network_header(skb)); if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL) return NET_RX_DROP; cb = DN_SKB_CB(skb); /* Skip packet length and point to flags */ ptr = skb->data + 2; *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS; dst = (__le16 *)ptr; ptr += 2; src = (__le16 *)ptr; ptr += 2; *ptr = 0; /* Zero hop count */ swap(*src, *dst); skb->pkt_type = PACKET_OUTGOING; dn_rt_finish_output(skb, NULL, NULL); return NET_RX_SUCCESS; } /** * dn_return_long - Return a long packet to its sender * @skb: The long format packet to return * */ static int dn_return_long(struct sk_buff *skb) { struct dn_skb_cb *cb; unsigned char *ptr; unsigned char *src_addr, *dst_addr; unsigned char tmp[ETH_ALEN]; /* Add back all headers */ skb_push(skb, skb->data - skb_network_header(skb)); if ((skb = skb_unshare(skb, GFP_ATOMIC)) == NULL) return NET_RX_DROP; cb = DN_SKB_CB(skb); /* Ignore packet length and point to flags */ ptr = skb->data + 2; /* Skip padding */ if (*ptr & DN_RT_F_PF) { char padlen = (*ptr & ~DN_RT_F_PF); ptr += padlen; } *ptr++ = (cb->rt_flags & ~DN_RT_F_RQR) | DN_RT_F_RTS; ptr += 2; dst_addr = ptr; ptr += 8; src_addr = ptr; ptr += 6; *ptr = 0; /* Zero hop count */ /* Swap source and destination */ memcpy(tmp, src_addr, ETH_ALEN); memcpy(src_addr, dst_addr, ETH_ALEN); memcpy(dst_addr, tmp, ETH_ALEN); skb->pkt_type = PACKET_OUTGOING; dn_rt_finish_output(skb, dst_addr, src_addr); return NET_RX_SUCCESS; } /** * dn_route_rx_packet - Try and find a route for an incoming packet * @skb: The packet to find a route for * * Returns: result of input function if route is found, error code otherwise */ static int dn_route_rx_packet(struct sk_buff *skb) { struct dn_skb_cb *cb; int err; if ((err = dn_route_input(skb)) == 0) return dst_input(skb); cb = DN_SKB_CB(skb); if (decnet_debug_level & 4) { char *devname = skb->dev ? skb->dev->name : "???"; printk(KERN_DEBUG "DECnet: dn_route_rx_packet: rt_flags=0x%02x dev=%s len=%d src=0x%04hx dst=0x%04hx err=%d type=%d\n", (int)cb->rt_flags, devname, skb->len, le16_to_cpu(cb->src), le16_to_cpu(cb->dst), err, skb->pkt_type); } if ((skb->pkt_type == PACKET_HOST) && (cb->rt_flags & DN_RT_F_RQR)) { switch (cb->rt_flags & DN_RT_PKT_MSK) { case DN_RT_PKT_SHORT: return dn_return_short(skb); case DN_RT_PKT_LONG: return dn_return_long(skb); } } kfree_skb(skb); return NET_RX_DROP; } static int dn_route_rx_long(struct sk_buff *skb) { struct dn_skb_cb *cb = DN_SKB_CB(skb); unsigned char *ptr = skb->data; if (!pskb_may_pull(skb, 21)) /* 20 for long header, 1 for shortest nsp */ goto drop_it; skb_pull(skb, 20); skb_reset_transport_header(skb); /* Destination info */ ptr += 2; cb->dst = dn_eth2dn(ptr); if (memcmp(ptr, dn_hiord_addr, 4) != 0) goto drop_it; ptr += 6; /* Source info */ ptr += 2; cb->src = dn_eth2dn(ptr); if (memcmp(ptr, dn_hiord_addr, 4) != 0) goto drop_it; ptr += 6; /* Other junk */ ptr++; cb->hops = *ptr++; /* Visit Count */ return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet); drop_it: kfree_skb(skb); return NET_RX_DROP; } static int dn_route_rx_short(struct sk_buff *skb) { struct dn_skb_cb *cb = DN_SKB_CB(skb); unsigned char *ptr = skb->data; if (!pskb_may_pull(skb, 6)) /* 5 for short header + 1 for shortest nsp */ goto drop_it; skb_pull(skb, 5); skb_reset_transport_header(skb); cb->dst = *(__le16 *)ptr; ptr += 2; cb->src = *(__le16 *)ptr; ptr += 2; cb->hops = *ptr & 0x3f; return NF_HOOK(NFPROTO_DECNET, NF_DN_PRE_ROUTING, skb, skb->dev, NULL, dn_route_rx_packet); drop_it: kfree_skb(skb); return NET_RX_DROP; } static int dn_route_discard(struct sk_buff *skb) { /* * I know we drop the packet here, but thats considered success in * this case */ kfree_skb(skb); return NET_RX_SUCCESS; } static int dn_route_ptp_hello(struct sk_buff *skb) { dn_dev_hello(skb); dn_neigh_pointopoint_hello(skb); return NET_RX_SUCCESS; } int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct dn_skb_cb *cb; unsigned char flags = 0; __u16 len = le16_to_cpu(*(__le16 *)skb->data); struct dn_dev *dn = rcu_dereference(dev->dn_ptr); unsigned char padlen = 0; if (!net_eq(dev_net(dev), &init_net)) goto dump_it; if (dn == NULL) goto dump_it; if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) goto out; if (!pskb_may_pull(skb, 3)) goto dump_it; skb_pull(skb, 2); if (len > skb->len) goto dump_it; skb_trim(skb, len); flags = *skb->data; cb = DN_SKB_CB(skb); cb->stamp = jiffies; cb->iif = dev->ifindex; /* * If we have padding, remove it. */ if (flags & DN_RT_F_PF) { padlen = flags & ~DN_RT_F_PF; if (!pskb_may_pull(skb, padlen + 1)) goto dump_it; skb_pull(skb, padlen); flags = *skb->data; } skb_reset_network_header(skb); /* * Weed out future version DECnet */ if (flags & DN_RT_F_VER) goto dump_it; cb->rt_flags = flags; if (decnet_debug_level & 1) printk(KERN_DEBUG "dn_route_rcv: got 0x%02x from %s [%d %d %d]\n", (int)flags, (dev) ? dev->name : "???", len, skb->len, padlen); if (flags & DN_RT_PKT_CNTL) { if (unlikely(skb_linearize(skb))) goto dump_it; switch (flags & DN_RT_CNTL_MSK) { case DN_RT_PKT_INIT: dn_dev_init_pkt(skb); break; case DN_RT_PKT_VERI: dn_dev_veri_pkt(skb); break; } if (dn->parms.state != DN_DEV_S_RU) goto dump_it; switch (flags & DN_RT_CNTL_MSK) { case DN_RT_PKT_HELO: return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO, skb, skb->dev, NULL, dn_route_ptp_hello); case DN_RT_PKT_L1RT: case DN_RT_PKT_L2RT: return NF_HOOK(NFPROTO_DECNET, NF_DN_ROUTE, skb, skb->dev, NULL, dn_route_discard); case DN_RT_PKT_ERTH: return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_router_hello); case DN_RT_PKT_EEDH: return NF_HOOK(NFPROTO_DECNET, NF_DN_HELLO, skb, skb->dev, NULL, dn_neigh_endnode_hello); } } else { if (dn->parms.state != DN_DEV_S_RU) goto dump_it; skb_pull(skb, 1); /* Pull flags */ switch (flags & DN_RT_PKT_MSK) { case DN_RT_PKT_LONG: return dn_route_rx_long(skb); case DN_RT_PKT_SHORT: return dn_route_rx_short(skb); } } dump_it: kfree_skb(skb); out: return NET_RX_DROP; } static int dn_to_neigh_output(struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct dn_route *rt = (struct dn_route *) dst; struct neighbour *n = rt->n; return n->output(n, skb); } static int dn_output(struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct dn_route *rt = (struct dn_route *)dst; struct net_device *dev = dst->dev; struct dn_skb_cb *cb = DN_SKB_CB(skb); int err = -EINVAL; if (rt->n == NULL) goto error; skb->dev = dev; cb->src = rt->rt_saddr; cb->dst = rt->rt_daddr; /* * Always set the Intra-Ethernet bit on all outgoing packets * originated on this node. Only valid flag from upper layers * is return-to-sender-requested. Set hop count to 0 too. */ cb->rt_flags &= ~DN_RT_F_RQR; cb->rt_flags |= DN_RT_F_IE; cb->hops = 0; return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_OUT, skb, NULL, dev, dn_to_neigh_output); error: net_dbg_ratelimited("dn_output: This should not happen\n"); kfree_skb(skb); return err; } static int dn_forward(struct sk_buff *skb) { struct dn_skb_cb *cb = DN_SKB_CB(skb); struct dst_entry *dst = skb_dst(skb); struct dn_dev *dn_db = rcu_dereference(dst->dev->dn_ptr); struct dn_route *rt; int header_len; #ifdef CONFIG_NETFILTER struct net_device *dev = skb->dev; #endif if (skb->pkt_type != PACKET_HOST) goto drop; /* Ensure that we have enough space for headers */ rt = (struct dn_route *)skb_dst(skb); header_len = dn_db->use_long ? 21 : 6; if (skb_cow(skb, LL_RESERVED_SPACE(rt->dst.dev)+header_len)) goto drop; /* * Hop count exceeded. */ if (++cb->hops > 30) goto drop; skb->dev = rt->dst.dev; /* * If packet goes out same interface it came in on, then set * the Intra-Ethernet bit. This has no effect for short * packets, so we don't need to test for them here. */ cb->rt_flags &= ~DN_RT_F_IE; if (rt->rt_flags & RTCF_DOREDIRECT) cb->rt_flags |= DN_RT_F_IE; return NF_HOOK(NFPROTO_DECNET, NF_DN_FORWARD, skb, dev, skb->dev, dn_to_neigh_output); drop: kfree_skb(skb); return NET_RX_DROP; } /* * Used to catch bugs. This should never normally get * called. */ static int dn_rt_bug(struct sk_buff *skb) { struct dn_skb_cb *cb = DN_SKB_CB(skb); net_dbg_ratelimited("dn_rt_bug: skb from:%04x to:%04x\n", le16_to_cpu(cb->src), le16_to_cpu(cb->dst)); kfree_skb(skb); return NET_RX_DROP; } static unsigned int dn_dst_default_advmss(const struct dst_entry *dst) { return dn_mss_from_pmtu(dst->dev, dst_mtu(dst)); } static unsigned int dn_dst_mtu(const struct dst_entry *dst) { unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); return mtu ? : dst->dev->mtu; } static struct neighbour *dn_dst_neigh_lookup(const struct dst_entry *dst, struct sk_buff *skb, const void *daddr) { return __neigh_lookup_errno(&dn_neigh_table, daddr, dst->dev); } static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res) { struct dn_fib_info *fi = res->fi; struct net_device *dev = rt->dst.dev; unsigned int mss_metric; struct neighbour *n; if (fi) { if (DN_FIB_RES_GW(*res) && DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) rt->rt_gateway = DN_FIB_RES_GW(*res); dst_init_metrics(&rt->dst, fi->fib_metrics, true); } rt->rt_type = res->type; if (dev != NULL && rt->n == NULL) { n = __neigh_lookup_errno(&dn_neigh_table, &rt->rt_gateway, dev); if (IS_ERR(n)) return PTR_ERR(n); rt->n = n; } if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu) dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu); mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS); if (mss_metric) { unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst)); if (mss_metric > mss) dst_metric_set(&rt->dst, RTAX_ADVMSS, mss); } return 0; } static inline int dn_match_addr(__le16 addr1, __le16 addr2) { __u16 tmp = le16_to_cpu(addr1) ^ le16_to_cpu(addr2); int match = 16; while(tmp) { tmp >>= 1; match--; } return match; } static __le16 dnet_select_source(const struct net_device *dev, __le16 daddr, int scope) { __le16 saddr = 0; struct dn_dev *dn_db; struct dn_ifaddr *ifa; int best_match = 0; int ret; rcu_read_lock(); dn_db = rcu_dereference(dev->dn_ptr); for (ifa = rcu_dereference(dn_db->ifa_list); ifa != NULL; ifa = rcu_dereference(ifa->ifa_next)) { if (ifa->ifa_scope > scope) continue; if (!daddr) { saddr = ifa->ifa_local; break; } ret = dn_match_addr(daddr, ifa->ifa_local); if (ret > best_match) saddr = ifa->ifa_local; if (best_match == 0) saddr = ifa->ifa_local; } rcu_read_unlock(); return saddr; } static inline __le16 __dn_fib_res_prefsrc(struct dn_fib_res *res) { return dnet_select_source(DN_FIB_RES_DEV(*res), DN_FIB_RES_GW(*res), res->scope); } static inline __le16 dn_fib_rules_map_destination(__le16 daddr, struct dn_fib_res *res) { __le16 mask = dnet_make_mask(res->prefixlen); return (daddr&~mask)|res->fi->fib_nh->nh_gw; } static int dn_route_output_slow(struct dst_entry **pprt, const struct flowidn *oldflp, int try_hard) { struct flowidn fld = { .daddr = oldflp->daddr, .saddr = oldflp->saddr, .flowidn_scope = RT_SCOPE_UNIVERSE, .flowidn_mark = oldflp->flowidn_mark, .flowidn_iif = 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 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, 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, DST_OBSOLETE_NONE, DST_HOST); if (rt == NULL) goto e_nobufs; memset(&rt->fld, 0, sizeof(rt->fld)); rt->fld.saddr = oldflp->saddr; rt->fld.daddr = oldflp->daddr; rt->fld.flowidn_oif = oldflp->flowidn_oif; rt->fld.flowidn_iif = 0; rt->fld.flowidn_mark = oldflp->flowidn_mark; rt->rt_saddr = fld.saddr; rt->rt_daddr = fld.daddr; rt->rt_gateway = gateway ? gateway : fld.daddr; rt->rt_local_src = fld.saddr; rt->rt_dst_map = fld.daddr; rt->rt_src_map = fld.saddr; rt->n = neigh; neigh = NULL; rt->dst.lastuse = jiffies; rt->dst.output = dn_output; rt->dst.input = dn_rt_bug; rt->rt_flags = flags; if (flags & RTCF_LOCAL) rt->dst.input = dn_nsp_rx; err = dn_rt_set_next_hop(rt, &res); if (err) goto e_neighbour; hash = dn_hash(rt->fld.saddr, rt->fld.daddr); dn_insert_route(rt, hash, (struct dn_route **)pprt); done: if (neigh) neigh_release(neigh); if (free_res) dn_fib_res_put(&res); if (dev_out) dev_put(dev_out); out: return err; e_addr: err = -EADDRNOTAVAIL; goto done; e_inval: err = -EINVAL; goto done; e_nobufs: err = -ENOBUFS; goto done; e_neighbour: dst_free(&rt->dst); goto e_nobufs; } /* * N.B. The flags may be moved into the flowi at some future stage. */ static int __dn_route_output_key(struct dst_entry **pprt, const struct flowidn *flp, int flags) { unsigned int hash = dn_hash(flp->saddr, flp->daddr); struct dn_route *rt = NULL; if (!(flags & MSG_TRYHARD)) { rcu_read_lock_bh(); for (rt = rcu_dereference_bh(dn_rt_hash_table[hash].chain); rt; rt = rcu_dereference_bh(rt->dst.dn_next)) { if ((flp->daddr == rt->fld.daddr) && (flp->saddr == rt->fld.saddr) && (flp->flowidn_mark == rt->fld.flowidn_mark) && dn_is_output_route(rt) && (rt->fld.flowidn_oif == flp->flowidn_oif)) { dst_use(&rt->dst, jiffies); rcu_read_unlock_bh(); *pprt = &rt->dst; return 0; } } rcu_read_unlock_bh(); } return dn_route_output_slow(pprt, flp, flags); } static int dn_route_output_key(struct dst_entry **pprt, struct flowidn *flp, int flags) { int err; err = __dn_route_output_key(pprt, flp, flags); if (err == 0 && flp->flowidn_proto) { *pprt = xfrm_lookup(&init_net, *pprt, flowidn_to_flowi(flp), NULL, 0); if (IS_ERR(*pprt)) { err = PTR_ERR(*pprt); *pprt = NULL; } } return err; } int dn_route_output_sock(struct dst_entry **pprt, struct flowidn *fl, struct sock *sk, int flags) { int err; err = __dn_route_output_key(pprt, fl, flags & MSG_TRYHARD); if (err == 0 && fl->flowidn_proto) { if (!(flags & MSG_DONTWAIT)) fl->flowidn_flags |= FLOWI_FLAG_CAN_SLEEP; *pprt = xfrm_lookup(&init_net, *pprt, flowidn_to_flowi(fl), sk, 0); if (IS_ERR(*pprt)) { err = PTR_ERR(*pprt); *pprt = NULL; } } return err; } static int dn_route_input_slow(struct sk_buff *skb) { struct dn_route *rt = NULL; struct dn_skb_cb *cb = DN_SKB_CB(skb); struct net_device *in_dev = skb->dev; struct net_device *out_dev = NULL; struct dn_dev *dn_db; struct neighbour *neigh = NULL; unsigned int hash; int flags = 0; __le16 gateway = 0; __le16 local_src = 0; struct flowidn fld = { .daddr = cb->dst, .saddr = cb->src, .flowidn_scope = RT_SCOPE_UNIVERSE, .flowidn_mark = skb->mark, .flowidn_iif = skb->dev->ifindex, }; struct dn_fib_res res = { .fi = NULL, .type = RTN_UNREACHABLE }; int err = -EINVAL; int free_res = 0; dev_hold(in_dev); if ((dn_db = rcu_dereference(in_dev->dn_ptr)) == NULL) goto out; /* Zero source addresses are not allowed */ if (fld.saddr == 0) goto out; /* * In this case we've just received a packet from a source * outside ourselves pretending to come from us. We don't * allow it any further to prevent routing loops, spoofing and * other nasties. Loopback packets already have the dst attached * so this only affects packets which have originated elsewhere. */ err = -ENOTUNIQ; if (dn_dev_islocal(in_dev, cb->src)) goto out; err = dn_fib_lookup(&fld, &res); if (err) { if (err != -ESRCH) goto out; /* * Is the destination us ? */ if (!dn_dev_islocal(in_dev, cb->dst)) goto e_inval; res.type = RTN_LOCAL; } else { __le16 src_map = fld.saddr; free_res = 1; out_dev = DN_FIB_RES_DEV(res); if (out_dev == NULL) { net_crit_ratelimited("Bug in dn_route_input_slow() No output device\n"); goto e_inval; } dev_hold(out_dev); if (res.r) src_map = fld.saddr; /* no NAT support for now */ gateway = DN_FIB_RES_GW(res); if (res.type == RTN_NAT) { fld.daddr = dn_fib_rules_map_destination(fld.daddr, &res); dn_fib_res_put(&res); free_res = 0; if (dn_fib_lookup(&fld, &res)) goto e_inval; free_res = 1; if (res.type != RTN_UNICAST) goto e_inval; flags |= RTCF_DNAT; gateway = fld.daddr; } fld.saddr = src_map; } switch(res.type) { case RTN_UNICAST: /* * Forwarding check here, we only check for forwarding * being turned off, if you want to only forward intra * area, its up to you to set the routing tables up * correctly. */ if (dn_db->parms.forwarding == 0) goto e_inval; if (res.fi->fib_nhs > 1 && fld.flowidn_oif == 0) dn_fib_select_multipath(&fld, &res); /* * Check for out_dev == in_dev. We use the RTCF_DOREDIRECT * flag as a hint to set the intra-ethernet bit when * forwarding. If we've got NAT in operation, we don't do * this optimisation. */ if (out_dev == in_dev && !(flags & RTCF_NAT)) flags |= RTCF_DOREDIRECT; local_src = DN_FIB_RES_PREFSRC(res); case RTN_BLACKHOLE: case RTN_UNREACHABLE: break; case RTN_LOCAL: flags |= RTCF_LOCAL; fld.saddr = cb->dst; fld.daddr = cb->src; /* Routing tables gave us a gateway */ if (gateway) goto make_route; /* Packet was intra-ethernet, so we know its on-link */ if (cb->rt_flags & DN_RT_F_IE) { gateway = cb->src; goto make_route; } /* Use the default router if there is one */ neigh = neigh_clone(dn_db->router); if (neigh) { gateway = ((struct dn_neigh *)neigh)->addr; goto make_route; } /* Close eyes and pray */ gateway = cb->src; goto make_route; default: goto e_inval; } make_route: rt = dst_alloc(&dn_dst_ops, out_dev, 0, DST_OBSOLETE_NONE, DST_HOST); if (rt == NULL) goto e_nobufs; memset(&rt->fld, 0, sizeof(rt->fld)); rt->rt_saddr = fld.saddr; rt->rt_daddr = fld.daddr; rt->rt_gateway = fld.daddr; if (gateway) rt->rt_gateway = gateway; rt->rt_local_src = local_src ? local_src : rt->rt_saddr; rt->rt_dst_map = fld.daddr; rt->rt_src_map = fld.saddr; rt->fld.saddr = cb->src; rt->fld.daddr = cb->dst; rt->fld.flowidn_oif = 0; rt->fld.flowidn_iif = in_dev->ifindex; rt->fld.flowidn_mark = fld.flowidn_mark; rt->n = neigh; rt->dst.lastuse = jiffies; rt->dst.output = dn_rt_bug; switch (res.type) { case RTN_UNICAST: rt->dst.input = dn_forward; break; case RTN_LOCAL: rt->dst.output = dn_output; rt->dst.input = dn_nsp_rx; rt->dst.dev = in_dev; flags |= RTCF_LOCAL; break; default: case RTN_UNREACHABLE: case RTN_BLACKHOLE: rt->dst.input = dst_discard; } rt->rt_flags = flags; err = dn_rt_set_next_hop(rt, &res); if (err) goto e_neighbour; hash = dn_hash(rt->fld.saddr, rt->fld.daddr); dn_insert_route(rt, hash, &rt); skb_dst_set(skb, &rt->dst); done: if (neigh) neigh_release(neigh); if (free_res) dn_fib_res_put(&res); dev_put(in_dev); if (out_dev) dev_put(out_dev); out: return err; e_inval: err = -EINVAL; goto done; e_nobufs: err = -ENOBUFS; goto done; e_neighbour: dst_free(&rt->dst); goto done; } static int dn_route_input(struct sk_buff *skb) { struct dn_route *rt; struct dn_skb_cb *cb = DN_SKB_CB(skb); unsigned int hash = dn_hash(cb->src, cb->dst); if (skb_dst(skb)) return 0; rcu_read_lock(); for(rt = rcu_dereference(dn_rt_hash_table[hash].chain); rt != NULL; rt = rcu_dereference(rt->dst.dn_next)) { if ((rt->fld.saddr == cb->src) && (rt->fld.daddr == cb->dst) && (rt->fld.flowidn_oif == 0) && (rt->fld.flowidn_mark == skb->mark) && (rt->fld.flowidn_iif == cb->iif)) { dst_use(&rt->dst, jiffies); rcu_read_unlock(); skb_dst_set(skb, (struct dst_entry *)rt); return 0; } } rcu_read_unlock(); return dn_route_input_slow(skb); } static int dn_rt_fill_info(struct sk_buff *skb, u32 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; long expires; nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); if (!nlh) return -EMSGSIZE; r = nlmsg_data(nlh); r->rtm_family = AF_DECnet; r->rtm_dst_len = 16; r->rtm_src_len = 0; r->rtm_tos = 0; r->rtm_table = RT_TABLE_MAIN; r->rtm_type = rt->rt_type; r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; r->rtm_scope = RT_SCOPE_UNIVERSE; r->rtm_protocol = RTPROT_UNSPEC; if (rt->rt_flags & RTCF_NOTIFY) r->rtm_flags |= RTM_F_NOTIFY; if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN) < 0 || nla_put_le16(skb, RTA_DST, rt->rt_daddr) < 0) goto errout; if (rt->fld.saddr) { r->rtm_src_len = 16; if (nla_put_le16(skb, RTA_SRC, rt->fld.saddr) < 0) goto errout; } if (rt->dst.dev && nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex) < 0) goto errout; /* * Note to self - change this if input routes reverse direction when * they deal only with inputs and not with replies like they do * currently. */ if (nla_put_le16(skb, RTA_PREFSRC, rt->rt_local_src) < 0) goto errout; if (rt->rt_daddr != rt->rt_gateway && nla_put_le16(skb, RTA_GATEWAY, rt->rt_gateway) < 0) goto errout; if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) goto errout; expires = rt->dst.expires ? rt->dst.expires - jiffies : 0; if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0) goto errout; if (dn_is_input_route(rt) && nla_put_u32(skb, RTA_IIF, rt->fld.flowidn_iif) < 0) goto errout; return nlmsg_end(skb, nlh); errout: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } /* * This is called by both endnodes and routers now. */ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg) { struct net *net = sock_net(in_skb->sk); struct rtattr **rta = arg; struct rtmsg *rtm = nlmsg_data(nlh); struct dn_route *rt = NULL; struct dn_skb_cb *cb; int err; struct sk_buff *skb; struct flowidn fld; if (!net_eq(net, &init_net)) return -EINVAL; memset(&fld, 0, sizeof(fld)); fld.flowidn_proto = DNPROTO_NSP; skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (skb == NULL) return -ENOBUFS; skb_reset_mac_header(skb); cb = DN_SKB_CB(skb); if (rta[RTA_SRC-1]) memcpy(&fld.saddr, RTA_DATA(rta[RTA_SRC-1]), 2); if (rta[RTA_DST-1]) memcpy(&fld.daddr, RTA_DATA(rta[RTA_DST-1]), 2); if (rta[RTA_IIF-1]) memcpy(&fld.flowidn_iif, RTA_DATA(rta[RTA_IIF-1]), sizeof(int)); if (fld.flowidn_iif) { struct net_device *dev; if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) { kfree_skb(skb); return -ENODEV; } if (!dev->dn_ptr) { dev_put(dev); kfree_skb(skb); return -ENODEV; } skb->protocol = htons(ETH_P_DNA_RT); skb->dev = dev; cb->src = fld.saddr; cb->dst = fld.daddr; local_bh_disable(); err = dn_route_input(skb); local_bh_enable(); memset(cb, 0, sizeof(struct dn_skb_cb)); rt = (struct dn_route *)skb_dst(skb); if (!err && -rt->dst.error) err = rt->dst.error; } else { int oif = 0; if (rta[RTA_OIF - 1]) memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int)); fld.flowidn_oif = oif; err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0); } if (skb->dev) dev_put(skb->dev); skb->dev = NULL; if (err) goto out_free; skb_dst_set(skb, &rt->dst); if (rtm->rtm_flags & RTM_F_NOTIFY) rt->rt_flags |= RTCF_NOTIFY; err = dn_rt_fill_info(skb, NETLINK_CB(in_skb).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; 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).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, 0); return 0; } static const struct seq_operations dn_rt_cache_seq_ops = { .start = dn_rt_cache_seq_start, .next = dn_rt_cache_seq_next, .stop = dn_rt_cache_seq_stop, .show = dn_rt_cache_seq_show, }; static int dn_rt_cache_seq_open(struct inode *inode, struct file *file) { return seq_open_private(file, &dn_rt_cache_seq_ops, sizeof(struct dn_rt_cache_iter_state)); } static const struct file_operations dn_rt_cache_seq_fops = { .owner = THIS_MODULE, .open = dn_rt_cache_seq_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release_private, }; #endif /* CONFIG_PROC_FS */ void __init dn_route_init(void) { int i, goal, order; dn_dst_ops.kmem_cachep = kmem_cache_create("dn_dst_cache", sizeof(struct dn_route), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); dst_entries_init(&dn_dst_ops); setup_timer(&dn_route_timer, dn_dst_check_expire, 0); dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ; add_timer(&dn_route_timer); goal = totalram_pages >> (26 - PAGE_SHIFT); for(order = 0; (1UL << order) < goal; order++) /* NOTHING */; /* * Only want 1024 entries max, since the table is very, very unlikely * to be larger than that. */ while(order && ((((1UL << order) * PAGE_SIZE) / sizeof(struct dn_rt_hash_bucket)) >= 2048)) order--; do { dn_rt_hash_mask = (1UL << order) * PAGE_SIZE / sizeof(struct dn_rt_hash_bucket); while(dn_rt_hash_mask & (dn_rt_hash_mask - 1)) dn_rt_hash_mask--; dn_rt_hash_table = (struct dn_rt_hash_bucket *) __get_free_pages(GFP_ATOMIC, order); } while (dn_rt_hash_table == NULL && --order > 0); if (!dn_rt_hash_table) panic("Failed to allocate DECnet route cache hash table\n"); printk(KERN_INFO "DECnet: Routing cache hash table of %u buckets, %ldKbytes\n", dn_rt_hash_mask, (long)(dn_rt_hash_mask*sizeof(struct dn_rt_hash_bucket))/1024); dn_rt_hash_mask--; for(i = 0; i <= dn_rt_hash_mask; i++) { spin_lock_init(&dn_rt_hash_table[i].lock); dn_rt_hash_table[i].chain = NULL; } dn_dst_ops.gc_thresh = (dn_rt_hash_mask + 1); proc_net_fops_create(&init_net, "decnet_cache", S_IRUGO, &dn_rt_cache_seq_fops); #ifdef CONFIG_DECNET_ROUTER rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_fib_dump, NULL); #else rtnl_register(PF_DECnet, RTM_GETROUTE, dn_cache_getroute, dn_cache_dump, NULL); #endif } void __exit dn_route_cleanup(void) { del_timer(&dn_route_timer); dn_run_flush(0); proc_net_remove(&init_net, "decnet_cache"); dst_entries_destroy(&dn_dst_ops); }