--- zzzz-none-000/linux-3.10.107/net/batman-adv/gateway_client.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/net/batman-adv/gateway_client.c 2021-02-04 17:41:59.000000000 +0000 @@ -1,4 +1,4 @@ -/* Copyright (C) 2009-2013 B.A.T.M.A.N. contributors: +/* Copyright (C) 2009-2015 B.A.T.M.A.N. contributors: * * Marek Lindner * @@ -12,34 +12,59 @@ * 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 + * along with this program; if not, see . */ -#include "main.h" -#include "sysfs.h" #include "gateway_client.h" +#include "main.h" + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + #include "gateway_common.h" #include "hard-interface.h" #include "originator.h" -#include "translation-table.h" +#include "packet.h" #include "routing.h" -#include -#include -#include -#include +#include "sysfs.h" +#include "translation-table.h" -/* This is the offset of the options field in a dhcp packet starting at - * the beginning of the dhcp header +/* These are the offsets of the "hw type" and "hw address length" in the dhcp + * packet starting at the beginning of the dhcp header + */ +#define BATADV_DHCP_HTYPE_OFFSET 1 +#define BATADV_DHCP_HLEN_OFFSET 2 +/* Value of htype representing Ethernet */ +#define BATADV_DHCP_HTYPE_ETHERNET 0x01 +/* This is the offset of the "chaddr" field in the dhcp packet starting at the + * beginning of the dhcp header */ -#define BATADV_DHCP_OPTIONS_OFFSET 240 -#define BATADV_DHCP_REQUEST 3 +#define BATADV_DHCP_CHADDR_OFFSET 28 static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node) { - if (atomic_dec_and_test(&gw_node->refcount)) + if (atomic_dec_and_test(&gw_node->refcount)) { + batadv_orig_node_free_ref(gw_node->orig_node); kfree_rcu(gw_node, rcu); + } } static struct batadv_gw_node * @@ -105,7 +130,18 @@ spin_unlock_bh(&bat_priv->gw.list_lock); } -void batadv_gw_deselect(struct batadv_priv *bat_priv) +/** + * batadv_gw_reselect - force a gateway reselection + * @bat_priv: the bat priv with all the soft interface information + * + * Set a flag to remind the GW component to perform a new gateway reselection. + * However this function does not ensure that the current gateway is going to be + * deselected. The reselection mechanism may elect the same gateway once again. + * + * This means that invoking batadv_gw_reselect() does not guarantee a gateway + * change and therefore a uevent is not necessarily expected. + */ +void batadv_gw_reselect(struct batadv_priv *bat_priv) { atomic_set(&bat_priv->gw.reselect, 1); } @@ -114,39 +150,37 @@ batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv) { struct batadv_neigh_node *router; + struct batadv_neigh_ifinfo *router_ifinfo; struct batadv_gw_node *gw_node, *curr_gw = NULL; - uint32_t max_gw_factor = 0, tmp_gw_factor = 0; - uint32_t gw_divisor; - uint8_t max_tq = 0; - int down, up; - uint8_t tq_avg; + u64 max_gw_factor = 0; + u64 tmp_gw_factor = 0; + u8 max_tq = 0; + u8 tq_avg; struct batadv_orig_node *orig_node; - gw_divisor = BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE; - gw_divisor *= 64; - rcu_read_lock(); hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) { - if (gw_node->deleted) - continue; - orig_node = gw_node->orig_node; - router = batadv_orig_node_get_router(orig_node); + router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT); if (!router) continue; + router_ifinfo = batadv_neigh_ifinfo_get(router, + BATADV_IF_DEFAULT); + if (!router_ifinfo) + goto next; + if (!atomic_inc_not_zero(&gw_node->refcount)) goto next; - tq_avg = router->tq_avg; + tq_avg = router_ifinfo->bat_iv.tq_avg; switch (atomic_read(&bat_priv->gw_sel_class)) { case 1: /* fast connection */ - batadv_gw_bandwidth_to_kbit(orig_node->gw_flags, - &down, &up); - - tmp_gw_factor = tq_avg * tq_avg * down * 100 * 100; - tmp_gw_factor /= gw_divisor; + tmp_gw_factor = tq_avg * tq_avg; + tmp_gw_factor *= gw_node->bandwidth_down; + tmp_gw_factor *= 100 * 100; + tmp_gw_factor >>= 18; if ((tmp_gw_factor > max_gw_factor) || ((tmp_gw_factor == max_gw_factor) && @@ -184,23 +218,54 @@ next: batadv_neigh_node_free_ref(router); + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); } rcu_read_unlock(); return curr_gw; } +/** + * batadv_gw_check_client_stop - check if client mode has been switched off + * @bat_priv: the bat priv with all the soft interface information + * + * This function assumes the caller has checked that the gw state *is actually + * changing*. This function is not supposed to be called when there is no state + * change. + */ +void batadv_gw_check_client_stop(struct batadv_priv *bat_priv) +{ + struct batadv_gw_node *curr_gw; + + if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT) + return; + + curr_gw = batadv_gw_get_selected_gw_node(bat_priv); + if (!curr_gw) + return; + + /* deselect the current gateway so that next time that client mode is + * enabled a proper GW_ADD event can be sent + */ + batadv_gw_select(bat_priv, NULL); + + /* if batman-adv is switching the gw client mode off and a gateway was + * already selected, send a DEL uevent + */ + batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL, NULL); + + batadv_gw_node_free_ref(curr_gw); +} + void batadv_gw_election(struct batadv_priv *bat_priv) { - struct batadv_gw_node *curr_gw = NULL, *next_gw = NULL; + struct batadv_gw_node *curr_gw = NULL; + struct batadv_gw_node *next_gw = NULL; struct batadv_neigh_node *router = NULL; + struct batadv_neigh_ifinfo *router_ifinfo = NULL; char gw_addr[18] = { '\0' }; - /* 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) != BATADV_GW_MODE_CLIENT) goto out; @@ -217,9 +282,17 @@ if (next_gw) { sprintf(gw_addr, "%pM", next_gw->orig_node->orig); - router = batadv_orig_node_get_router(next_gw->orig_node); + router = batadv_orig_router_get(next_gw->orig_node, + BATADV_IF_DEFAULT); if (!router) { - batadv_gw_deselect(bat_priv); + batadv_gw_reselect(bat_priv); + goto out; + } + + router_ifinfo = batadv_neigh_ifinfo_get(router, + BATADV_IF_DEFAULT); + if (!router_ifinfo) { + batadv_gw_reselect(bat_priv); goto out; } } @@ -231,16 +304,24 @@ NULL); } else if ((!curr_gw) && (next_gw)) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, - "Adding route to gateway %pM (gw_flags: %i, tq: %i)\n", + "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n", next_gw->orig_node->orig, - next_gw->orig_node->gw_flags, router->tq_avg); + next_gw->bandwidth_down / 10, + next_gw->bandwidth_down % 10, + next_gw->bandwidth_up / 10, + next_gw->bandwidth_up % 10, + router_ifinfo->bat_iv.tq_avg); batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD, gw_addr); } else { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, - "Changing route to gateway %pM (gw_flags: %i, tq: %i)\n", + "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n", next_gw->orig_node->orig, - next_gw->orig_node->gw_flags, router->tq_avg); + next_gw->bandwidth_down / 10, + next_gw->bandwidth_down % 10, + next_gw->bandwidth_up / 10, + next_gw->bandwidth_up % 10, + router_ifinfo->bat_iv.tq_avg); batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE, gw_addr); } @@ -254,33 +335,48 @@ batadv_gw_node_free_ref(next_gw); if (router) batadv_neigh_node_free_ref(router); + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); } void batadv_gw_check_election(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node) { + struct batadv_neigh_ifinfo *router_orig_tq = NULL; + struct batadv_neigh_ifinfo *router_gw_tq = NULL; struct batadv_orig_node *curr_gw_orig; - struct batadv_neigh_node *router_gw = NULL, *router_orig = NULL; - uint8_t gw_tq_avg, orig_tq_avg; + struct batadv_neigh_node *router_gw = NULL; + struct batadv_neigh_node *router_orig = NULL; + u8 gw_tq_avg, orig_tq_avg; curr_gw_orig = batadv_gw_get_selected_orig(bat_priv); if (!curr_gw_orig) - goto deselect; + goto reselect; - router_gw = batadv_orig_node_get_router(curr_gw_orig); + router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT); if (!router_gw) - goto deselect; + goto reselect; + + router_gw_tq = batadv_neigh_ifinfo_get(router_gw, + BATADV_IF_DEFAULT); + if (!router_gw_tq) + goto reselect; /* this node already is the gateway */ if (curr_gw_orig == orig_node) goto out; - router_orig = batadv_orig_node_get_router(orig_node); + router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT); if (!router_orig) goto out; - gw_tq_avg = router_gw->tq_avg; - orig_tq_avg = router_orig->tq_avg; + router_orig_tq = batadv_neigh_ifinfo_get(router_orig, + BATADV_IF_DEFAULT); + if (!router_orig_tq) + goto out; + + gw_tq_avg = router_gw_tq->bat_iv.tq_avg; + orig_tq_avg = router_orig_tq->bat_iv.tq_avg; /* the TQ value has to be better */ if (orig_tq_avg < gw_tq_avg) @@ -297,8 +393,8 @@ "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n", gw_tq_avg, orig_tq_avg); -deselect: - batadv_gw_deselect(bat_priv); +reselect: + batadv_gw_reselect(bat_priv); out: if (curr_gw_orig) batadv_orig_node_free_ref(curr_gw_orig); @@ -306,131 +402,172 @@ batadv_neigh_node_free_ref(router_gw); if (router_orig) batadv_neigh_node_free_ref(router_orig); - - return; + if (router_gw_tq) + batadv_neigh_ifinfo_free_ref(router_gw_tq); + if (router_orig_tq) + batadv_neigh_ifinfo_free_ref(router_orig_tq); } +/** + * batadv_gw_node_add - add gateway node to list of available gateways + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: originator announcing gateway capabilities + * @gateway: announced bandwidth information + */ static void batadv_gw_node_add(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node, - uint8_t new_gwflags) + struct batadv_tvlv_gateway_data *gateway) { struct batadv_gw_node *gw_node; - int down, up; + + if (gateway->bandwidth_down == 0) + return; + + if (!atomic_inc_not_zero(&orig_node->refcount)) + return; gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC); - if (!gw_node) + if (!gw_node) { + batadv_orig_node_free_ref(orig_node); return; + } INIT_HLIST_NODE(&gw_node->list); gw_node->orig_node = orig_node; + gw_node->bandwidth_down = ntohl(gateway->bandwidth_down); + gw_node->bandwidth_up = ntohl(gateway->bandwidth_up); 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); - batadv_gw_bandwidth_to_kbit(new_gwflags, &down, &up); batadv_dbg(BATADV_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")); + "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n", + orig_node->orig, + ntohl(gateway->bandwidth_down) / 10, + ntohl(gateway->bandwidth_down) % 10, + ntohl(gateway->bandwidth_up) / 10, + ntohl(gateway->bandwidth_up) % 10); } -void batadv_gw_node_update(struct batadv_priv *bat_priv, - struct batadv_orig_node *orig_node, - uint8_t new_gwflags) +/** + * batadv_gw_node_get - retrieve gateway node from list of available gateways + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: originator announcing gateway capabilities + * + * Returns gateway node if found or NULL otherwise. + */ +static struct batadv_gw_node * +batadv_gw_node_get(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node) { - struct batadv_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 = batadv_gw_get_selected_gw_node(bat_priv); + struct batadv_gw_node *gw_node_tmp, *gw_node = NULL; rcu_read_lock(); - hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) { - if (gw_node->orig_node != orig_node) + hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) { + if (gw_node_tmp->orig_node != orig_node) continue; - batadv_dbg(BATADV_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 == BATADV_NO_FLAGS) { - gw_node->deleted = jiffies; - batadv_dbg(BATADV_DBG_BATMAN, bat_priv, - "Gateway %pM removed from gateway list\n", - orig_node->orig); + if (!atomic_inc_not_zero(&gw_node_tmp->refcount)) + continue; - if (gw_node == curr_gw) - goto deselect; - } + gw_node = gw_node_tmp; + break; + } + rcu_read_unlock(); - goto unlock; + return gw_node; +} + +/** + * batadv_gw_node_update - update list of available gateways with changed + * bandwidth information + * @bat_priv: the bat priv with all the soft interface information + * @orig_node: originator announcing gateway capabilities + * @gateway: announced bandwidth information + */ +void batadv_gw_node_update(struct batadv_priv *bat_priv, + struct batadv_orig_node *orig_node, + struct batadv_tvlv_gateway_data *gateway) +{ + struct batadv_gw_node *gw_node, *curr_gw = NULL; + + gw_node = batadv_gw_node_get(bat_priv, orig_node); + if (!gw_node) { + batadv_gw_node_add(bat_priv, orig_node, gateway); + goto out; } - if (new_gwflags == BATADV_NO_FLAGS) - goto unlock; + if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) && + (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up))) + goto out; - batadv_gw_node_add(bat_priv, orig_node, new_gwflags); - goto unlock; + batadv_dbg(BATADV_DBG_BATMAN, bat_priv, + "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n", + orig_node->orig, + gw_node->bandwidth_down / 10, + gw_node->bandwidth_down % 10, + gw_node->bandwidth_up / 10, + gw_node->bandwidth_up % 10, + ntohl(gateway->bandwidth_down) / 10, + ntohl(gateway->bandwidth_down) % 10, + ntohl(gateway->bandwidth_up) / 10, + ntohl(gateway->bandwidth_up) % 10); -deselect: - batadv_gw_deselect(bat_priv); -unlock: - rcu_read_unlock(); + gw_node->bandwidth_down = ntohl(gateway->bandwidth_down); + gw_node->bandwidth_up = ntohl(gateway->bandwidth_up); - if (curr_gw) - batadv_gw_node_free_ref(curr_gw); + if (ntohl(gateway->bandwidth_down) == 0) { + batadv_dbg(BATADV_DBG_BATMAN, bat_priv, + "Gateway %pM removed from gateway list\n", + orig_node->orig); + + /* Note: We don't need a NULL check here, since curr_gw never + * gets dereferenced. + */ + spin_lock_bh(&bat_priv->gw.list_lock); + hlist_del_init_rcu(&gw_node->list); + spin_unlock_bh(&bat_priv->gw.list_lock); + + batadv_gw_node_free_ref(gw_node); + + curr_gw = batadv_gw_get_selected_gw_node(bat_priv); + if (gw_node == curr_gw) + batadv_gw_reselect(bat_priv); + + if (curr_gw) + batadv_gw_node_free_ref(curr_gw); + } + +out: + if (gw_node) + batadv_gw_node_free_ref(gw_node); } void batadv_gw_node_delete(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node) { - batadv_gw_node_update(bat_priv, orig_node, 0); + struct batadv_tvlv_gateway_data gateway; + + gateway.bandwidth_down = 0; + gateway.bandwidth_up = 0; + + batadv_gw_node_update(bat_priv, orig_node, &gateway); } -void batadv_gw_node_purge(struct batadv_priv *bat_priv) +void batadv_gw_node_free(struct batadv_priv *bat_priv) { - struct batadv_gw_node *gw_node, *curr_gw; + struct batadv_gw_node *gw_node; struct hlist_node *node_tmp; - unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT); - int do_deselect = 0; - - curr_gw = batadv_gw_get_selected_gw_node(bat_priv); spin_lock_bh(&bat_priv->gw.list_lock); - hlist_for_each_entry_safe(gw_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) == BATADV_MESH_ACTIVE) - continue; - - if (curr_gw == gw_node) - do_deselect = 1; - - hlist_del_rcu(&gw_node->list); + hlist_del_init_rcu(&gw_node->list); batadv_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) - batadv_gw_deselect(bat_priv); - - if (curr_gw) - batadv_gw_node_free_ref(curr_gw); } /* fails if orig_node has no router */ @@ -440,31 +577,37 @@ { struct batadv_gw_node *curr_gw; struct batadv_neigh_node *router; - int down, up, ret = -1; - - batadv_gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up); + struct batadv_neigh_ifinfo *router_ifinfo = NULL; + int ret = -1; - router = batadv_orig_node_get_router(gw_node->orig_node); + router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT); if (!router) goto out; + router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT); + if (!router_ifinfo) + goto out; + curr_gw = batadv_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")); + seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n", + (curr_gw == gw_node ? "=>" : " "), + gw_node->orig_node->orig, + router_ifinfo->bat_iv.tq_avg, router->addr, + router->if_incoming->net_dev->name, + gw_node->bandwidth_down / 10, + gw_node->bandwidth_down % 10, + gw_node->bandwidth_up / 10, + gw_node->bandwidth_up % 10); + ret = seq_has_overflowed(seq) ? -1 : 0; - batadv_neigh_node_free_ref(router); if (curr_gw) batadv_gw_node_free_ref(curr_gw); out: + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); + if (router) + batadv_neigh_node_free_ref(router); return ret; } @@ -481,16 +624,13 @@ goto out; seq_printf(seq, - " %-12s (%s/%i) %17s [%10s]: gw_class ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n", + " %-12s (%s/%i) %17s [%10s]: advertised uplink bandwidth ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n", "Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF", BATADV_SOURCE_VERSION, primary_if->net_dev->name, primary_if->net_dev->dev_addr, net_dev->name); rcu_read_lock(); hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) { - if (gw_node->deleted) - continue; - /* fails if orig_node has no router */ if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0) continue; @@ -508,156 +648,163 @@ return 0; } -static bool batadv_is_type_dhcprequest(struct sk_buff *skb, int header_len) -{ - int ret = false; - unsigned char *p; - int pkt_len; - - if (skb_linearize(skb) < 0) - goto out; - - pkt_len = skb_headlen(skb); - - if (pkt_len < header_len + BATADV_DHCP_OPTIONS_OFFSET + 1) - goto out; - - p = skb->data + header_len + BATADV_DHCP_OPTIONS_OFFSET; - pkt_len -= header_len + BATADV_DHCP_OPTIONS_OFFSET + 1; - - /* Access the dhcp option lists. Each entry is made up by: - * - octet 1: option type - * - octet 2: option data len (only if type != 255 and 0) - * - octet 3: option data - */ - while (*p != 255 && !ret) { - /* p now points to the first octet: option type */ - if (*p == 53) { - /* type 53 is the message type option. - * Jump the len octet and go to the data octet - */ - if (pkt_len < 2) - goto out; - p += 2; - - /* check if the message type is what we need */ - if (*p == BATADV_DHCP_REQUEST) - ret = true; - break; - } else if (*p == 0) { - /* option type 0 (padding), just go forward */ - if (pkt_len < 1) - goto out; - pkt_len--; - p++; - } else { - /* This is any other option. So we get the length... */ - if (pkt_len < 1) - goto out; - pkt_len--; - p++; - - /* ...and then we jump over the data */ - if (pkt_len < 1 + (*p)) - goto out; - pkt_len -= 1 + (*p); - p += 1 + (*p); - } - } -out: - return ret; -} - -bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) +/** + * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message + * @skb: the packet to check + * @header_len: a pointer to the batman-adv header size + * @chaddr: buffer where the client address will be stored. Valid + * only if the function returns BATADV_DHCP_TO_CLIENT + * + * Returns: + * - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error + * while parsing it + * - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server + * - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client + * + * This function may re-allocate the data buffer of the skb passed as argument. + */ +enum batadv_dhcp_recipient +batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len, + u8 *chaddr) { + enum batadv_dhcp_recipient ret = BATADV_DHCP_NO; struct ethhdr *ethhdr; struct iphdr *iphdr; struct ipv6hdr *ipv6hdr; struct udphdr *udphdr; + struct vlan_ethhdr *vhdr; + int chaddr_offset; + __be16 proto; + u8 *p; /* check for ethernet header */ if (!pskb_may_pull(skb, *header_len + ETH_HLEN)) - return false; - ethhdr = (struct ethhdr *)skb->data; + return BATADV_DHCP_NO; + + ethhdr = eth_hdr(skb); + proto = ethhdr->h_proto; *header_len += ETH_HLEN; /* check for initial vlan header */ - if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) { + if (proto == htons(ETH_P_8021Q)) { if (!pskb_may_pull(skb, *header_len + VLAN_HLEN)) - return false; - ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN); + return BATADV_DHCP_NO; + + vhdr = vlan_eth_hdr(skb); + proto = vhdr->h_vlan_encapsulated_proto; *header_len += VLAN_HLEN; } /* check for ip header */ - switch (ntohs(ethhdr->h_proto)) { - case ETH_P_IP: + switch (proto) { + case htons(ETH_P_IP): if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr))) - return false; + return BATADV_DHCP_NO; + iphdr = (struct iphdr *)(skb->data + *header_len); *header_len += iphdr->ihl * 4; /* check for udp header */ if (iphdr->protocol != IPPROTO_UDP) - return false; + return BATADV_DHCP_NO; break; - case ETH_P_IPV6: + case htons(ETH_P_IPV6): if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr))) - return false; + return BATADV_DHCP_NO; + ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len); *header_len += sizeof(*ipv6hdr); /* check for udp header */ if (ipv6hdr->nexthdr != IPPROTO_UDP) - return false; + return BATADV_DHCP_NO; break; default: - return false; + return BATADV_DHCP_NO; } if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr))) - return false; + return BATADV_DHCP_NO; + udphdr = (struct udphdr *)(skb->data + *header_len); *header_len += sizeof(*udphdr); /* check for bootp port */ - if ((ntohs(ethhdr->h_proto) == ETH_P_IP) && - (ntohs(udphdr->dest) != 67)) - return false; - - if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) && - (ntohs(udphdr->dest) != 547)) - return false; + switch (proto) { + case htons(ETH_P_IP): + if (udphdr->dest == htons(67)) + ret = BATADV_DHCP_TO_SERVER; + else if (udphdr->source == htons(67)) + ret = BATADV_DHCP_TO_CLIENT; + break; + case htons(ETH_P_IPV6): + if (udphdr->dest == htons(547)) + ret = BATADV_DHCP_TO_SERVER; + else if (udphdr->source == htons(547)) + ret = BATADV_DHCP_TO_CLIENT; + break; + } + + chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET; + /* store the client address if the message is going to a client */ + if (ret == BATADV_DHCP_TO_CLIENT && + pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) { + /* check if the DHCP packet carries an Ethernet DHCP */ + p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET; + if (*p != BATADV_DHCP_HTYPE_ETHERNET) + return BATADV_DHCP_NO; + + /* check if the DHCP packet carries a valid Ethernet address */ + p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET; + if (*p != ETH_ALEN) + return BATADV_DHCP_NO; - return true; + ether_addr_copy(chaddr, skb->data + chaddr_offset); + } + + return ret; } +/** + * batadv_gw_out_of_range - check if the dhcp request destination is the best gw + * @bat_priv: the bat priv with all the soft interface information + * @skb: the outgoing packet + * + * Check if the skb is a DHCP request and if it is sent to the current best GW + * server. Due to topology changes it may be the case that the GW server + * previously selected is not the best one anymore. + * + * Returns true if the packet destination is unicast and it is not the best gw, + * false otherwise. + * + * This call might reallocate skb data. + * Must be invoked only when the DHCP packet is going TO a DHCP SERVER. + */ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, - struct sk_buff *skb, struct ethhdr *ethhdr) + struct sk_buff *skb) { - struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL; + struct batadv_neigh_node *neigh_curr = NULL; + struct batadv_neigh_node *neigh_old = NULL; struct batadv_orig_node *orig_dst_node = NULL; + struct batadv_gw_node *gw_node = NULL; struct batadv_gw_node *curr_gw = NULL; - bool ret, out_of_range = false; - unsigned int header_len = 0; - uint8_t curr_tq_avg; + struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo; + struct ethhdr *ethhdr = (struct ethhdr *)skb->data; + bool out_of_range = false; + u8 curr_tq_avg; + unsigned short vid; - ret = batadv_gw_is_dhcp_target(skb, &header_len); - if (!ret) - goto out; + vid = batadv_get_vid(skb, 0); orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source, - ethhdr->h_dest); + ethhdr->h_dest, vid); if (!orig_dst_node) goto out; - if (!orig_dst_node->gw_flags) - goto out; - - ret = batadv_is_type_dhcprequest(skb, header_len); - if (!ret) + gw_node = batadv_gw_node_get(bat_priv, orig_dst_node); + if (!gw_node) goto out; switch (atomic_read(&bat_priv->gw_mode)) { @@ -685,7 +832,14 @@ if (!neigh_curr) goto out; - curr_tq_avg = neigh_curr->tq_avg; + curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr, + BATADV_IF_DEFAULT); + if (!curr_ifinfo) + goto out; + + curr_tq_avg = curr_ifinfo->bat_iv.tq_avg; + batadv_neigh_ifinfo_free_ref(curr_ifinfo); + break; case BATADV_GW_MODE_OFF: default: @@ -696,14 +850,21 @@ if (!neigh_old) goto out; - if (curr_tq_avg - neigh_old->tq_avg > BATADV_GW_THRESHOLD) + old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT); + if (!old_ifinfo) + goto out; + + if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD) out_of_range = true; + batadv_neigh_ifinfo_free_ref(old_ifinfo); out: if (orig_dst_node) batadv_orig_node_free_ref(orig_dst_node); if (curr_gw) batadv_gw_node_free_ref(curr_gw); + if (gw_node) + batadv_gw_node_free_ref(gw_node); if (neigh_old) batadv_neigh_node_free_ref(neigh_old); if (neigh_curr)