/* * Copyright (C) 2009-2011 B.A.T.M.A.N. contributors: * * Marek Lindner * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA * */ #include "main.h" #include "gateway_client.h" #include "gateway_common.h" #include "hard-interface.h" #include "originator.h" #include #include #include #include static void gw_node_free_ref(struct gw_node *gw_node) { if (atomic_dec_and_test(&gw_node->refcount)) kfree_rcu(gw_node, rcu); } static struct gw_node *gw_get_selected_gw_node(struct bat_priv *bat_priv) { struct gw_node *gw_node; rcu_read_lock(); gw_node = rcu_dereference(bat_priv->curr_gw); if (!gw_node) goto out; if (!atomic_inc_not_zero(&gw_node->refcount)) gw_node = NULL; out: rcu_read_unlock(); return gw_node; } struct orig_node *gw_get_selected_orig(struct bat_priv *bat_priv) { struct gw_node *gw_node; struct orig_node *orig_node = NULL; gw_node = gw_get_selected_gw_node(bat_priv); if (!gw_node) goto out; rcu_read_lock(); orig_node = gw_node->orig_node; if (!orig_node) goto unlock; if (!atomic_inc_not_zero(&orig_node->refcount)) orig_node = NULL; unlock: rcu_read_unlock(); out: if (gw_node) gw_node_free_ref(gw_node); return orig_node; } static void gw_select(struct bat_priv *bat_priv, struct gw_node *new_gw_node) { struct gw_node *curr_gw_node; spin_lock_bh(&bat_priv->gw_list_lock); if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount)) new_gw_node = NULL; curr_gw_node = bat_priv->curr_gw; rcu_assign_pointer(bat_priv->curr_gw, new_gw_node); if (curr_gw_node) gw_node_free_ref(curr_gw_node); spin_unlock_bh(&bat_priv->gw_list_lock); } void gw_deselect(struct bat_priv *bat_priv) { gw_select(bat_priv, NULL); } void gw_election(struct bat_priv *bat_priv) { struct hlist_node *node; struct gw_node *gw_node, *curr_gw = NULL, *curr_gw_tmp = NULL; struct neigh_node *router; uint8_t max_tq = 0; uint32_t max_gw_factor = 0, tmp_gw_factor = 0; int down, up; /** * The batman daemon checks here if we already passed a full originator * cycle in order to make sure we don't choose the first gateway we * hear about. This check is based on the daemon's uptime which we * don't have. **/ if (atomic_read(&bat_priv->gw_mode) != GW_MODE_CLIENT) return; curr_gw = gw_get_selected_gw_node(bat_priv); if (curr_gw) goto out; rcu_read_lock(); if (hlist_empty(&bat_priv->gw_list)) { bat_dbg(DBG_BATMAN, bat_priv, "Removing selected gateway - " "no gateway in range\n"); gw_deselect(bat_priv); goto unlock; } hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) { if (gw_node->deleted) continue; router = orig_node_get_router(gw_node->orig_node); if (!router) continue; switch (atomic_read(&bat_priv->gw_sel_class)) { case 1: /* fast connection */ gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up); tmp_gw_factor = (router->tq_avg * router->tq_avg * down * 100 * 100) / (TQ_LOCAL_WINDOW_SIZE * TQ_LOCAL_WINDOW_SIZE * 64); if ((tmp_gw_factor > max_gw_factor) || ((tmp_gw_factor == max_gw_factor) && (router->tq_avg > max_tq))) curr_gw_tmp = gw_node; break; default: /** * 2: stable connection (use best statistic) * 3: fast-switch (use best statistic but change as * soon as a better gateway appears) * XX: late-switch (use best statistic but change as * soon as a better gateway appears which has * $routing_class more tq points) **/ if (router->tq_avg > max_tq) curr_gw_tmp = gw_node; break; } if (router->tq_avg > max_tq) max_tq = router->tq_avg; if (tmp_gw_factor > max_gw_factor) max_gw_factor = tmp_gw_factor; neigh_node_free_ref(router); } if (curr_gw != curr_gw_tmp) { router = orig_node_get_router(curr_gw_tmp->orig_node); if (!router) goto unlock; if ((curr_gw) && (!curr_gw_tmp)) bat_dbg(DBG_BATMAN, bat_priv, "Removing selected gateway - " "no gateway in range\n"); else if ((!curr_gw) && (curr_gw_tmp)) bat_dbg(DBG_BATMAN, bat_priv, "Adding route to gateway %pM " "(gw_flags: %i, tq: %i)\n", curr_gw_tmp->orig_node->orig, curr_gw_tmp->orig_node->gw_flags, router->tq_avg); else bat_dbg(DBG_BATMAN, bat_priv, "Changing route to gateway %pM " "(gw_flags: %i, tq: %i)\n", curr_gw_tmp->orig_node->orig, curr_gw_tmp->orig_node->gw_flags, router->tq_avg); neigh_node_free_ref(router); gw_select(bat_priv, curr_gw_tmp); } unlock: rcu_read_unlock(); out: if (curr_gw) gw_node_free_ref(curr_gw); } void gw_check_election(struct bat_priv *bat_priv, struct orig_node *orig_node) { struct orig_node *curr_gw_orig; struct neigh_node *router_gw = NULL, *router_orig = NULL; uint8_t gw_tq_avg, orig_tq_avg; curr_gw_orig = gw_get_selected_orig(bat_priv); if (!curr_gw_orig) goto deselect; router_gw = orig_node_get_router(curr_gw_orig); if (!router_gw) goto deselect; /* this node already is the gateway */ if (curr_gw_orig == orig_node) goto out; router_orig = orig_node_get_router(orig_node); if (!router_orig) goto out; gw_tq_avg = router_gw->tq_avg; orig_tq_avg = router_orig->tq_avg; /* the TQ value has to be better */ if (orig_tq_avg < gw_tq_avg) goto out; /** * if the routing class is greater than 3 the value tells us how much * greater the TQ value of the new gateway must be **/ if ((atomic_read(&bat_priv->gw_sel_class) > 3) && (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class))) goto out; bat_dbg(DBG_BATMAN, bat_priv, "Restarting gateway selection: better gateway found (tq curr: " "%i, tq new: %i)\n", gw_tq_avg, orig_tq_avg); deselect: gw_deselect(bat_priv); out: if (curr_gw_orig) orig_node_free_ref(curr_gw_orig); if (router_gw) neigh_node_free_ref(router_gw); if (router_orig) neigh_node_free_ref(router_orig); return; } static void gw_node_add(struct bat_priv *bat_priv, struct orig_node *orig_node, uint8_t new_gwflags) { struct gw_node *gw_node; int down, up; gw_node = kzalloc(sizeof(struct gw_node), GFP_ATOMIC); if (!gw_node) return; INIT_HLIST_NODE(&gw_node->list); gw_node->orig_node = orig_node; atomic_set(&gw_node->refcount, 1); spin_lock_bh(&bat_priv->gw_list_lock); hlist_add_head_rcu(&gw_node->list, &bat_priv->gw_list); spin_unlock_bh(&bat_priv->gw_list_lock); gw_bandwidth_to_kbit(new_gwflags, &down, &up); bat_dbg(DBG_BATMAN, bat_priv, "Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n", orig_node->orig, new_gwflags, (down > 2048 ? down / 1024 : down), (down > 2048 ? "MBit" : "KBit"), (up > 2048 ? up / 1024 : up), (up > 2048 ? "MBit" : "KBit")); } void gw_node_update(struct bat_priv *bat_priv, struct orig_node *orig_node, uint8_t new_gwflags) { struct hlist_node *node; struct gw_node *gw_node, *curr_gw; /** * Note: We don't need a NULL check here, since curr_gw never gets * dereferenced. If curr_gw is NULL we also should not exit as we may * have this gateway in our list (duplication check!) even though we * have no currently selected gateway. */ curr_gw = gw_get_selected_gw_node(bat_priv); rcu_read_lock(); hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) { if (gw_node->orig_node != orig_node) continue; bat_dbg(DBG_BATMAN, bat_priv, "Gateway class of originator %pM changed from " "%i to %i\n", orig_node->orig, gw_node->orig_node->gw_flags, new_gwflags); gw_node->deleted = 0; if (new_gwflags == 0) { gw_node->deleted = jiffies; bat_dbg(DBG_BATMAN, bat_priv, "Gateway %pM removed from gateway list\n", orig_node->orig); if (gw_node == curr_gw) goto deselect; } goto unlock; } if (new_gwflags == 0) goto unlock; gw_node_add(bat_priv, orig_node, new_gwflags); goto unlock; deselect: gw_deselect(bat_priv); unlock: rcu_read_unlock(); if (curr_gw) gw_node_free_ref(curr_gw); } void gw_node_delete(struct bat_priv *bat_priv, struct orig_node *orig_node) { return gw_node_update(bat_priv, orig_node, 0); } void gw_node_purge(struct bat_priv *bat_priv) { struct gw_node *gw_node, *curr_gw; struct hlist_node *node, *node_tmp; unsigned long timeout = 2 * PURGE_TIMEOUT * HZ; char do_deselect = 0; curr_gw = gw_get_selected_gw_node(bat_priv); spin_lock_bh(&bat_priv->gw_list_lock); hlist_for_each_entry_safe(gw_node, node, node_tmp, &bat_priv->gw_list, list) { if (((!gw_node->deleted) || (time_before(jiffies, gw_node->deleted + timeout))) && atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE) continue; if (curr_gw == gw_node) do_deselect = 1; hlist_del_rcu(&gw_node->list); gw_node_free_ref(gw_node); } spin_unlock_bh(&bat_priv->gw_list_lock); /* gw_deselect() needs to acquire the gw_list_lock */ if (do_deselect) gw_deselect(bat_priv); if (curr_gw) gw_node_free_ref(curr_gw); } /** * fails if orig_node has no router */ static int _write_buffer_text(struct bat_priv *bat_priv, struct seq_file *seq, struct gw_node *gw_node) { struct gw_node *curr_gw; struct neigh_node *router; int down, up, ret = -1; gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up); router = orig_node_get_router(gw_node->orig_node); if (!router) goto out; curr_gw = gw_get_selected_gw_node(bat_priv); ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n", (curr_gw == gw_node ? "=>" : " "), gw_node->orig_node->orig, router->tq_avg, router->addr, router->if_incoming->net_dev->name, gw_node->orig_node->gw_flags, (down > 2048 ? down / 1024 : down), (down > 2048 ? "MBit" : "KBit"), (up > 2048 ? up / 1024 : up), (up > 2048 ? "MBit" : "KBit")); neigh_node_free_ref(router); if (curr_gw) gw_node_free_ref(curr_gw); out: return ret; } int gw_client_seq_print_text(struct seq_file *seq, void *offset) { struct net_device *net_dev = (struct net_device *)seq->private; struct bat_priv *bat_priv = netdev_priv(net_dev); struct hard_iface *primary_if; struct gw_node *gw_node; struct hlist_node *node; int gw_count = 0, ret = 0; primary_if = primary_if_get_selected(bat_priv); if (!primary_if) { ret = seq_printf(seq, "BATMAN mesh %s disabled - please " "specify interfaces to enable it\n", net_dev->name); goto out; } if (primary_if->if_status != IF_ACTIVE) { ret = seq_printf(seq, "BATMAN mesh %s disabled - " "primary interface not active\n", net_dev->name); goto out; } seq_printf(seq, " %-12s (%s/%i) %17s [%10s]: gw_class ... " "[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n", "Gateway", "#", TQ_MAX_VALUE, "Nexthop", "outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR, primary_if->net_dev->name, primary_if->net_dev->dev_addr, net_dev->name); rcu_read_lock(); hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) { if (gw_node->deleted) continue; /* fails if orig_node has no router */ if (_write_buffer_text(bat_priv, seq, gw_node) < 0) continue; gw_count++; } rcu_read_unlock(); if (gw_count == 0) seq_printf(seq, "No gateways in range ...\n"); out: if (primary_if) hardif_free_ref(primary_if); return ret; } int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb) { struct ethhdr *ethhdr; struct iphdr *iphdr; struct ipv6hdr *ipv6hdr; struct udphdr *udphdr; struct gw_node *curr_gw; unsigned int header_len = 0; if (atomic_read(&bat_priv->gw_mode) == GW_MODE_OFF) return 0; /* check for ethernet header */ if (!pskb_may_pull(skb, header_len + ETH_HLEN)) return 0; ethhdr = (struct ethhdr *)skb->data; header_len += ETH_HLEN; /* check for initial vlan header */ if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) { if (!pskb_may_pull(skb, header_len + VLAN_HLEN)) return 0; ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN); header_len += VLAN_HLEN; } /* check for ip header */ switch (ntohs(ethhdr->h_proto)) { case ETH_P_IP: if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr))) return 0; iphdr = (struct iphdr *)(skb->data + header_len); header_len += iphdr->ihl * 4; /* check for udp header */ if (iphdr->protocol != IPPROTO_UDP) return 0; break; case ETH_P_IPV6: if (!pskb_may_pull(skb, header_len + sizeof(struct ipv6hdr))) return 0; ipv6hdr = (struct ipv6hdr *)(skb->data + header_len); header_len += sizeof(struct ipv6hdr); /* check for udp header */ if (ipv6hdr->nexthdr != IPPROTO_UDP) return 0; break; default: return 0; } if (!pskb_may_pull(skb, header_len + sizeof(struct udphdr))) return 0; udphdr = (struct udphdr *)(skb->data + header_len); header_len += sizeof(struct udphdr); /* check for bootp port */ if ((ntohs(ethhdr->h_proto) == ETH_P_IP) && (ntohs(udphdr->dest) != 67)) return 0; if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) && (ntohs(udphdr->dest) != 547)) return 0; if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER) return -1; curr_gw = gw_get_selected_gw_node(bat_priv); if (!curr_gw) return 0; if (curr_gw) gw_node_free_ref(curr_gw); return 1; }