diff options
Diffstat (limited to 'net/batman-adv/gateway_client.c')
-rw-r--r-- | net/batman-adv/gateway_client.c | 561 |
1 files changed, 561 insertions, 0 deletions
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c new file mode 100644 index 00000000..61605a0f --- /dev/null +++ b/net/batman-adv/gateway_client.c @@ -0,0 +1,561 @@ +/* + * 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 <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/udp.h> +#include <linux/if_vlan.h> + +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 = kmalloc(sizeof(struct gw_node), GFP_ATOMIC); + if (!gw_node) + return; + + memset(gw_node, 0, sizeof(struct gw_node)); + 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; +} |