By adding batadv_send_skb_to_orig() in send.c, we can remove duplicate code that looks up the next hop and then calls batadv_send_skb_packet().

Furthermore, this prepares the upcoming new implementation of fragmentation, which requires the next hop to route packets.

Please note that this doesn't entirely remove the next-hop lookup in routing.c and unicast.c, since it is used by the current fragmentation code.

Also note that the next-hop info is removed from debug messages in translation-table.c, since it is looked up elsewhere.

Signed-off-by: Martin Hundebøll martin@hundeboll.net --- routing.c | 37 +++++++----------------------- send.c | 20 +++++++++++++++++ send.h | 3 +++ translation-table.c | 65 ++++++++++++++--------------------------------------- unicast.c | 10 ++++----- vis.c | 35 ++++++++--------------------- 6 files changed, 62 insertions(+), 108 deletions(-)

diff --git a/routing.c b/routing.c index 939fc01..53d991c 100644 --- a/routing.c +++ b/routing.c @@ -284,7 +284,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, { struct batadv_hard_iface *primary_if = NULL; struct batadv_orig_node *orig_node = NULL; - struct batadv_neigh_node *router = NULL; struct batadv_icmp_packet_rr *icmp_packet; int ret = NET_RX_DROP;

@@ -306,10 +305,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, if (!orig_node) goto out;

- router = batadv_orig_node_get_router(orig_node); - if (!router) - goto out; - /* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, ETH_HLEN) < 0) goto out; @@ -321,14 +316,12 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv, icmp_packet->msg_type = BATADV_ECHO_REPLY; icmp_packet->header.ttl = BATADV_TTL;

- batadv_send_skb_packet(skb, router->if_incoming, router->addr); - ret = NET_RX_SUCCESS; + if (batadv_send_skb_to_orig(skb, orig_node, NULL)) + ret = NET_RX_SUCCESS;

out: if (primary_if) batadv_hardif_free_ref(primary_if); - if (router) - batadv_neigh_node_free_ref(router); if (orig_node) batadv_orig_node_free_ref(orig_node); return ret; @@ -339,7 +332,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv, { struct batadv_hard_iface *primary_if = NULL; struct batadv_orig_node *orig_node = NULL; - struct batadv_neigh_node *router = NULL; struct batadv_icmp_packet *icmp_packet; int ret = NET_RX_DROP;

@@ -361,10 +353,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv, if (!orig_node) goto out;

- router = batadv_orig_node_get_router(orig_node); - if (!router) - goto out; - /* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, ETH_HLEN) < 0) goto out; @@ -376,14 +364,12 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv, icmp_packet->msg_type = BATADV_TTL_EXCEEDED; icmp_packet->header.ttl = BATADV_TTL;

- batadv_send_skb_packet(skb, router->if_incoming, router->addr); - ret = NET_RX_SUCCESS; + if (batadv_send_skb_to_orig(skb, orig_node, NULL)) + ret = NET_RX_SUCCESS;

out: if (primary_if) batadv_hardif_free_ref(primary_if); - if (router) - batadv_neigh_node_free_ref(router); if (orig_node) batadv_orig_node_free_ref(orig_node); return ret; @@ -397,7 +383,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, struct batadv_icmp_packet_rr *icmp_packet; struct ethhdr *ethhdr; struct batadv_orig_node *orig_node = NULL; - struct batadv_neigh_node *router = NULL; int hdr_size = sizeof(struct batadv_icmp_packet); int ret = NET_RX_DROP;

@@ -446,10 +431,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, if (!orig_node) goto out;

- router = batadv_orig_node_get_router(orig_node); - if (!router) - goto out; - /* create a copy of the skb, if needed, to modify it. */ if (skb_cow(skb, ETH_HLEN) < 0) goto out; @@ -460,12 +441,10 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, icmp_packet->header.ttl--;

/* route it */ - batadv_send_skb_packet(skb, router->if_incoming, router->addr); - ret = NET_RX_SUCCESS; + if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) + ret = NET_RX_SUCCESS;

out: - if (router) - batadv_neigh_node_free_ref(router); if (orig_node) batadv_orig_node_free_ref(orig_node); return ret; @@ -907,8 +886,8 @@ static int batadv_route_unicast_packet(struct sk_buff *skb, skb->len + ETH_HLEN);

/* route it */ - batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = NET_RX_SUCCESS; + if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) + ret = NET_RX_SUCCESS;

out: if (neigh_node) diff --git a/send.c b/send.c index 570a8bc..4a6400f 100644 --- a/send.c +++ b/send.c @@ -77,6 +77,26 @@ send_skb_err: return NET_XMIT_DROP; }

+bool batadv_send_skb_to_orig(struct sk_buff *skb, + struct batadv_orig_node *orig_node, + struct batadv_hard_iface *recv_if) +{ + struct batadv_priv *bat_priv = orig_node->bat_priv; + struct batadv_neigh_node *neigh_node; + + /* batadv_find_router() increases neigh_nodes refcount if found. */ + neigh_node = batadv_find_router(bat_priv, orig_node, recv_if); + if (!neigh_node) + return false; + + /* route it */ + batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); + + batadv_neigh_node_free_ref(neigh_node); + + return true; +} + void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface) { struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); diff --git a/send.h b/send.h index 643329b..0078dec 100644 --- a/send.h +++ b/send.h @@ -23,6 +23,9 @@ int batadv_send_skb_packet(struct sk_buff *skb, struct batadv_hard_iface *hard_iface, const uint8_t *dst_addr); +bool batadv_send_skb_to_orig(struct sk_buff *skb, + struct batadv_orig_node *orig_node, + struct batadv_hard_iface *recv_if); void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface); int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv, const struct sk_buff *skb, diff --git a/translation-table.c b/translation-table.c index 37ae4a9..2cee8b2 100644 --- a/translation-table.c +++ b/translation-table.c @@ -1519,7 +1519,6 @@ static int batadv_send_tt_request(struct batadv_priv *bat_priv, { struct sk_buff *skb = NULL; struct batadv_tt_query_packet *tt_request; - struct batadv_neigh_node *neigh_node = NULL; struct batadv_hard_iface *primary_if; struct batadv_tt_req_node *tt_req_node = NULL; int ret = 1; @@ -1557,23 +1556,15 @@ static int batadv_send_tt_request(struct batadv_priv *bat_priv, if (full_table) tt_request->flags |= BATADV_TT_FULL_TABLE;

- neigh_node = batadv_orig_node_get_router(dst_orig_node); - if (!neigh_node) - goto out; - - batadv_dbg(BATADV_DBG_TT, bat_priv, - "Sending TT_REQUEST to %pM via %pM [%c]\n", - dst_orig_node->orig, neigh_node->addr, - (full_table ? 'F' : '.')); + batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n", + dst_orig_node->orig, (full_table ? 'F' : '.'));

batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);

- batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = 0; + if (batadv_send_skb_to_orig(skb, dst_orig_node, NULL)) + ret = 0;

out: - if (neigh_node) - batadv_neigh_node_free_ref(neigh_node); if (primary_if) batadv_hardif_free_ref(primary_if); if (ret) @@ -1593,7 +1584,6 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv, { struct batadv_orig_node *req_dst_orig_node = NULL; struct batadv_orig_node *res_dst_orig_node = NULL; - struct batadv_neigh_node *neigh_node = NULL; struct batadv_hard_iface *primary_if = NULL; uint8_t orig_ttvn, req_ttvn, ttvn; int ret = false; @@ -1619,10 +1609,6 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv, if (!res_dst_orig_node) goto out;

- neigh_node = batadv_orig_node_get_router(res_dst_orig_node); - if (!neigh_node) - goto out; - primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) goto out; @@ -1694,14 +1680,13 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv, tt_response->flags |= BATADV_TT_FULL_TABLE;

batadv_dbg(BATADV_DBG_TT, bat_priv, - "Sending TT_RESPONSE %pM via %pM for %pM (ttvn: %u)\n", - res_dst_orig_node->orig, neigh_node->addr, - req_dst_orig_node->orig, req_ttvn); + "Sending TT_RESPONSE %pM for %pM (ttvn: %u)\n", + res_dst_orig_node->orig, req_dst_orig_node->orig, req_ttvn);

batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);

- batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = true; + if (batadv_send_skb_to_orig(skb, res_dst_orig_node, NULL)) + ret = true; goto out;

unlock: @@ -1712,8 +1697,6 @@ out: batadv_orig_node_free_ref(res_dst_orig_node); if (req_dst_orig_node) batadv_orig_node_free_ref(req_dst_orig_node); - if (neigh_node) - batadv_neigh_node_free_ref(neigh_node); if (primary_if) batadv_hardif_free_ref(primary_if); if (!ret) @@ -1727,7 +1710,6 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv, struct batadv_tt_query_packet *tt_request) { struct batadv_orig_node *orig_node = NULL; - struct batadv_neigh_node *neigh_node = NULL; struct batadv_hard_iface *primary_if = NULL; uint8_t my_ttvn, req_ttvn, ttvn; int ret = false; @@ -1752,10 +1734,6 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv, if (!orig_node) goto out;

- neigh_node = batadv_orig_node_get_router(orig_node); - if (!neigh_node) - goto out; - primary_if = batadv_primary_if_get_selected(bat_priv); if (!primary_if) goto out; @@ -1819,14 +1797,14 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv, tt_response->flags |= BATADV_TT_FULL_TABLE;

batadv_dbg(BATADV_DBG_TT, bat_priv, - "Sending TT_RESPONSE to %pM via %pM [%c]\n", - orig_node->orig, neigh_node->addr, + "Sending TT_RESPONSE to %pM [%c]\n", + orig_node->orig, (tt_response->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));

batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);

- batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = true; + if (batadv_send_skb_to_orig(skb, orig_node, NULL)) + ret = true; goto out;

unlock: @@ -1834,8 +1812,6 @@ unlock: out: if (orig_node) batadv_orig_node_free_ref(orig_node); - if (neigh_node) - batadv_neigh_node_free_ref(neigh_node); if (primary_if) batadv_hardif_free_ref(primary_if); if (!ret) @@ -2103,7 +2079,6 @@ unlock: static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client, struct batadv_orig_node *orig_node) { - struct batadv_neigh_node *neigh_node = NULL; struct sk_buff *skb = NULL; struct batadv_roam_adv_packet *roam_adv_packet; int ret = 1; @@ -2136,23 +2111,17 @@ static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client, memcpy(roam_adv_packet->dst, orig_node->orig, ETH_ALEN); memcpy(roam_adv_packet->client, client, ETH_ALEN);

- neigh_node = batadv_orig_node_get_router(orig_node); - if (!neigh_node) - goto out; - batadv_dbg(BATADV_DBG_TT, bat_priv, - "Sending ROAMING_ADV to %pM (client %pM) via %pM\n", - orig_node->orig, client, neigh_node->addr); + "Sending ROAMING_ADV to %pM (client %pM)\n", + orig_node->orig, client);

batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);

- batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = 0; + if (batadv_send_skb_to_orig(skb, orig_node, NULL)) + ret = 0;

out: - if (neigh_node) - batadv_neigh_node_free_ref(neigh_node); - if (ret) + if (ret && skb) kfree_skb(skb); return; } diff --git a/unicast.c b/unicast.c index f397232..add5d1f 100644 --- a/unicast.c +++ b/unicast.c @@ -298,7 +298,7 @@ int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv) struct batadv_orig_node *orig_node; struct batadv_neigh_node *neigh_node; int data_len = skb->len; - int ret = 1; + int ret = NET_RX_DROP; unsigned int dev_mtu;

/* get routing information */ @@ -358,16 +358,16 @@ find_router: goto out; }

- batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); - ret = 0; - goto out; + + if (batadv_send_skb_to_orig(skb, orig_node, NULL)) + ret = NET_RX_SUCCESS;

out: if (neigh_node) batadv_neigh_node_free_ref(neigh_node); if (orig_node) batadv_orig_node_free_ref(orig_node); - if (ret == 1) + if (ret == NET_RX_DROP) kfree_skb(skb); return ret; } diff --git a/vis.c b/vis.c index 5abd145..79589a3 100644 --- a/vis.c +++ b/vis.c @@ -698,15 +698,12 @@ static void batadv_purge_vis_packets(struct batadv_priv *bat_priv) static void batadv_broadcast_vis_packet(struct batadv_priv *bat_priv, struct batadv_vis_info *info) { - struct batadv_neigh_node *router; struct batadv_hashtable *hash = bat_priv->orig_hash; struct hlist_node *node; struct hlist_head *head; struct batadv_orig_node *orig_node; struct batadv_vis_packet *packet; struct sk_buff *skb; - struct batadv_hard_iface *hard_iface; - uint8_t dstaddr[ETH_ALEN]; uint32_t i;

@@ -722,30 +719,20 @@ static void batadv_broadcast_vis_packet(struct batadv_priv *bat_priv, if (!(orig_node->flags & BATADV_VIS_SERVER)) continue;

- router = batadv_orig_node_get_router(orig_node); - if (!router) - continue; - /* don't send it if we already received the packet from * this node. */ if (batadv_recv_list_is_in(bat_priv, &info->recv_list, - orig_node->orig)) { - batadv_neigh_node_free_ref(router); + orig_node->orig)) continue; - }

memcpy(packet->target_orig, orig_node->orig, ETH_ALEN); - hard_iface = router->if_incoming; - memcpy(dstaddr, router->addr, ETH_ALEN); - - batadv_neigh_node_free_ref(router); - skb = skb_clone(info->skb_packet, GFP_ATOMIC); - if (skb) - batadv_send_skb_packet(skb, hard_iface, - dstaddr); + if (!skb) + continue;

+ if (!batadv_send_skb_to_orig(skb, orig_node, NULL)) + kfree_skb(skb); } rcu_read_unlock(); } @@ -755,7 +742,6 @@ static void batadv_unicast_vis_packet(struct batadv_priv *bat_priv, struct batadv_vis_info *info) { struct batadv_orig_node *orig_node; - struct batadv_neigh_node *router = NULL; struct sk_buff *skb; struct batadv_vis_packet *packet;

@@ -765,17 +751,14 @@ static void batadv_unicast_vis_packet(struct batadv_priv *bat_priv, if (!orig_node) goto out;

- router = batadv_orig_node_get_router(orig_node); - if (!router) + skb = skb_clone(info->skb_packet, GFP_ATOMIC); + if (!skb) goto out;

- skb = skb_clone(info->skb_packet, GFP_ATOMIC); - if (skb) - batadv_send_skb_packet(skb, router->if_incoming, router->addr); + if (!batadv_send_skb_to_orig(skb, orig_node, NULL)) + kfree_skb(skb);

out: - if (router) - batadv_neigh_node_free_ref(router); if (orig_node) batadv_orig_node_free_ref(orig_node); }

Fragments arriving at their destination are buffered for later merge. Merged packets are passed to the main receive function as had they never been fragmented.

Fragments are forwarded without merging if the MTU of the outgoing interface is smaller than the size of the merged packet.

Signed-off-by: Martin Hundebøll martin@hundeboll.net --- Makefile.kbuild | 1 + fragmentation.c | 372 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fragmentation.h | 31 +++++ main.c | 3 + main.h | 3 + originator.c | 12 +- packet.h | 29 +++++ routing.c | 59 +++++++++ routing.h | 2 + soft-interface.c | 4 + types.h | 33 +++++ 11 files changed, 548 insertions(+), 1 deletion(-) create mode 100644 fragmentation.c create mode 100644 fragmentation.h

diff --git a/Makefile.kbuild b/Makefile.kbuild index 9d622ad..49d9b49 100644 --- a/Makefile.kbuild +++ b/Makefile.kbuild @@ -23,6 +23,7 @@ batman-adv-y += bat_iv_ogm.o batman-adv-y += bitarray.o batman-adv-$(CONFIG_BATMAN_ADV_BLA) += bridge_loop_avoidance.o batman-adv-y += debugfs.o +batman-adv-y += fragmentation.o batman-adv-y += gateway_client.o batman-adv-y += gateway_common.o batman-adv-y += hard-interface.o diff --git a/fragmentation.c b/fragmentation.c new file mode 100644 index 0000000..839bb54 --- /dev/null +++ b/fragmentation.c @@ -0,0 +1,372 @@ +/* Copyright (C) 2012 B.A.T.M.A.N. contributors: + * + * Martin Hundebøll martin@hundeboll.net + * + * 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 "fragmentation.h" +#include "send.h" +#include "originator.h" +#include "routing.h" +#include "hard-interface.h" +#include "soft-interface.h" + + +/** + * batadv_frag_clear_list() - Delete entries in the fragment buffer list. + * @head: head of list with entries. + * + * Frees fragments in the passed hlist. Should be called with appropriate lock. + */ +static void batadv_frag_clear_list(struct hlist_head *head) +{ + struct batadv_frag_list_entry *entry; + struct hlist_node *node, *node_tmp; + + hlist_for_each_entry_safe(entry, node, node_tmp, head, list) { + hlist_del(node); + kfree_skb(entry->skb); + kfree(entry); + } +} + +/** + * batadv_frag_clear_orig() - Free fragments associated to an orig. + * @orig_node: Originator to free fragments from. + */ +void batadv_frag_clear_orig(struct batadv_orig_node *orig_node) +{ + uint8_t i; + + for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) { + spin_lock_bh(&orig_node->fragments[i].lock); + batadv_frag_clear_list(&orig_node->fragments[i].head); + orig_node->fragments[i].size = 0; + spin_unlock_bh(&orig_node->fragments[i].lock); + } +} + +/** + * batadv_frag_check_orig() - Free timed out fragments from an orig. + * @orig_node: originator to check fragments from. + * + * Check timestamp of every hlist in fragment table and delete all entries if + * timed out. + */ +void batadv_frag_check_orig(struct batadv_orig_node *orig_node) +{ + struct batadv_frag_table_entry *frags; + uint8_t i; + + for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) { + frags = &orig_node->fragments[i]; + spin_lock_bh(&frags->lock); + + if (!hlist_empty(&frags->head) && + batadv_has_timed_out(frags->timestamp, BATADV_FRAG_TIMEOUT)) + batadv_frag_clear_list(&frags->head); + + spin_unlock_bh(&frags->lock); + } +} + +/** + * batadv_frag_size_limit() - Maximum possible size of fragmented packet. + */ +static inline int batadv_frag_size_limit(void) +{ + int limit = BATADV_FRAG_MAX_FRAG_SIZE; + limit -= sizeof(struct batadv_frag_packet); + limit *= BATADV_FRAG_MAX_FRAGMENTS; + return limit; +} + +/** + * batadv_frag_init_list() - Check and prepare fragment buffer for new fragment. + * @frags: Entry in fragments table to init. + * @seqno: Sequence number of the received fragment. + * + * Make list ready for a fragment with sequence number "seqno". Delete existing + * entries if they have a "old" sequence number. + * + * Returns true if list is empty and caller can just insert the new fragment + * without searching for the right position. + * + * Caller must hold frags->lock. + */ +static bool batadv_frag_init_list(struct batadv_frag_table_entry *frags, + uint16_t seqno) +{ + if (frags->seqno == seqno) + return false; + + if (!hlist_empty(&frags->head)) + batadv_frag_clear_list(&frags->head); + + frags->size = 0; + frags->seqno = seqno; + + return true; +} + +/** + * batadv_frag_insert_packet() - Insert a fragment into an fragment buffer. + * @orig_node: Originator that the fragment was received from. + * @skb: skb to insert. + * @head: head to attach complete lists of fragments to. + * + * Insert a new fragment into the reverse ordered list in the right table entry. + * The hash table entry is cleared if "old" fragments exist in it. + * + * Returns true if skb is buffered, false on error. If the list has all the + * fragments needed to merge the packet, the list is moved to the passed head. + */ +static bool batadv_frag_insert_packet(struct batadv_orig_node *orig_node, + struct sk_buff *skb, + struct hlist_head *head) +{ + struct batadv_frag_table_entry *frags; + struct batadv_frag_list_entry *new = NULL, *curr = NULL; + struct batadv_frag_packet *packet; + struct hlist_node *node; + uint8_t bucket; + uint16_t seqno, hdr_size = sizeof(struct batadv_frag_packet); + + if (skb_linearize(skb) < 0) + goto err; + + packet = (struct batadv_frag_packet *)skb->data; + seqno = ntohs(packet->seqno); + bucket = seqno % BATADV_FRAG_BUFFER_COUNT; + + new = kmalloc(sizeof(*new), GFP_ATOMIC); + if (!new) + goto err; + + new->skb = skb; + new->no = packet->no; + + /* Select entry in the "fragment table" and delete any prior fragments + * with another sequence number. batadv_frag_init_list() returns true, + * if the list is empty at return. + */ + frags = &orig_node->fragments[bucket]; + spin_lock_bh(&frags->lock); + if (batadv_frag_init_list(frags, seqno)) { + hlist_add_head(&new->list, &frags->head); + frags->size = skb->len - hdr_size; + frags->timestamp = jiffies; + goto out; + } + + /* Find the position for the new fragment. */ + hlist_for_each_entry(curr, node, &frags->head, list) { + /* Drop packet if fragment already exists. */ + if (curr->no == new->no) + goto err_unlock; + + /* Order fragments from highest to lowest. */ + if (curr->no < new->no) { + hlist_add_before(&new->list, &curr->list); + frags->size += skb->len - hdr_size; + frags->timestamp = jiffies; + goto out; + } + } + + /* We reached the end of the list, so insert after 'curr'. */ + if (likely(curr)) { + hlist_add_after(&curr->list, &new->list); + frags->size += skb->len - hdr_size; + frags->timestamp = jiffies; + } + +out: + if (frags->size > batadv_frag_size_limit() || + ntohs(packet->total_size) > batadv_frag_size_limit()) { + /* Clear list if total size of either the list or the packet exceeds + * the maximum size of one merged packet. + */ + batadv_frag_clear_list(&frags->head); + frags->size = 0; + } else if (ntohs(packet->total_size) == frags->size) { + /* All fragments received. Hand over list to caller. */ + hlist_move_list(&frags->head, head); + frags->size = 0; + } + + spin_unlock_bh(&frags->lock); + return true; + +err_unlock: + spin_unlock_bh(&frags->lock); + kfree(new); +err: + return false; +} + +/** + * batadv_frag_merge_packets() - Merge a list of fragments. + * @head: head if list with fragments. + * @skb: Packet with total size of skb after merging. + * + * Expands the first skb in the list and copies the content of the remaining + * skb's into the expanded one. After doing so, it clears the list. + * + * Returns NULL on error. + */ +static struct sk_buff * +batadv_frag_merge_packets(struct hlist_head *head, struct sk_buff *skb) +{ + struct batadv_frag_packet *packet; + struct batadv_frag_list_entry *entry; + struct hlist_node *node; + struct sk_buff *skb_out = NULL; + int size, hdr_size = sizeof(struct batadv_frag_packet); + + /* Make sure incoming skb has non-bogus data. */ + packet = (struct batadv_frag_packet *)skb->data; + size = ntohs(packet->total_size); + if (size > batadv_frag_size_limit()) + goto free; + + /* Remove first entry, as this is the destination for the rest of the + * fragments. + */ + entry = hlist_entry(head->first, struct batadv_frag_list_entry, list); + hlist_del(&entry->list); + skb_out = entry->skb; + kfree(entry); + + /* Make room for the rest of the fragments. */ + if (pskb_expand_head(skb_out, 0, size - skb->len, GFP_ATOMIC) < 0) { + kfree_skb(skb_out); + goto free; + } + + /* Move the existing MAC header to just before the payload. (Override + * the fragment header.) + */ + skb_pull_rcsum(skb_out, hdr_size); + memmove(skb_out->data - ETH_HLEN, skb_mac_header(skb_out), ETH_HLEN); + skb_set_mac_header(skb_out, -ETH_HLEN); + skb_reset_network_header(skb_out); + skb_reset_transport_header(skb_out); + + /* Copy the payload of the each fragment into the last skb */ + hlist_for_each_entry(entry, node, head, list) { + size = entry->skb->len - hdr_size; + memcpy(skb_put(skb_out, size), entry->skb->data + hdr_size, size); + } + +free: + /* Locking is not needed, because 'head' is not part of any orig. */ + batadv_frag_clear_list(head); + return skb_out; +} + +/** + * batadv_frag_skb_buffer() - Buffer fragment for later merge. + * @skb: skb to buffer. + * @orig_node_src: Originator that the skb is received from. + * + * Add fragment to buffer and merge fragments if possible. + * + * There are three possible outcomes: 1) Packet is merged: Return true and + * set *skb to merged packet; 2) Packet is buffered: Return true and set *skb + * to NULL; 3) Error: Return false and leave skb as is. + */ +bool batadv_frag_skb_buffer(struct sk_buff **skb, + struct batadv_orig_node *orig_node_src) +{ + struct sk_buff *skb_out = NULL; + struct hlist_head head = HLIST_HEAD_INIT; + bool ret = false; + + /* Add packet to buffer and table entry if merge is possible. */ + if (!batadv_frag_insert_packet(orig_node_src, *skb, &head)) + goto out_err; + + /* Leave if more fragments are needed to merge. */ + if (hlist_empty(&head)) + goto out; + + skb_out = batadv_frag_merge_packets(&head, *skb); + if (!skb_out) + goto out_err; + +out: + *skb = skb_out; + ret = true; +out_err: + return ret; +} + +/** + * batadv_frag_skb_fwd() - Forward fragments that would exceed MTU when merged. + * @skb: skb to forward. + * @recv_if: Interface that the skb is received on. + * @orig_node_src: Originator that the skb is received from. + * + * Look up the next-hop of the fragments payload and check if the merged packet + * will exceed the MTU towards the next-hop. If so, the fragment is forwarded + * without merging it. + * + * Returns true if the fragment is consumed/forwarded, false otherwise. + */ +bool batadv_frag_skb_fwd(struct sk_buff *skb, + struct batadv_hard_iface *recv_if, + struct batadv_orig_node *orig_node_src) +{ + struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); + struct batadv_orig_node *orig_node_dst = NULL; + struct batadv_neigh_node *neigh_node = NULL; + struct batadv_frag_packet *packet; + uint16_t total_size; + bool ret = false; + + packet = (struct batadv_frag_packet *)skb->data; + orig_node_dst = batadv_orig_hash_find(bat_priv, packet->dest); + if (!orig_node_dst) + goto out; + + neigh_node = batadv_find_router(bat_priv, orig_node_dst, recv_if); + if (!neigh_node) + goto out; + + /* Forward the fragment, if the merged packet would be too big to + * be assembled. + */ + total_size = ntohs(packet->total_size) + ETH_HLEN; + if (total_size > neigh_node->if_incoming->net_dev->mtu) { + batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_FWD); + batadv_add_counter(bat_priv, BATADV_CNT_FRAG_FWD_BYTES, + skb->len + ETH_HLEN); + + packet->header.ttl--; + batadv_send_skb_packet(skb, neigh_node->if_incoming, + neigh_node->addr); + ret = true; + } + +out: + if (orig_node_dst) + batadv_orig_node_free_ref(orig_node_dst); + if (neigh_node) + batadv_neigh_node_free_ref(neigh_node); + return ret; +} diff --git a/fragmentation.h b/fragmentation.h new file mode 100644 index 0000000..16d1a62 --- /dev/null +++ b/fragmentation.h @@ -0,0 +1,31 @@ +/* Copyright (C) 2012 B.A.T.M.A.N. contributors: + * + * Martin Hundebøll martin@hundeboll.net + * + * 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 + */ + +#ifndef _NET_BATMAN_ADV_FRAGMENTATION_H_ +#define _NET_BATMAN_ADV_FRAGMENTATION_H_ + +void batadv_frag_clear_orig(struct batadv_orig_node *orig); +void batadv_frag_check_orig(struct batadv_orig_node *orig); +bool batadv_frag_skb_fwd(struct sk_buff *skb, + struct batadv_hard_iface *recv_if, + struct batadv_orig_node *orig_node_src); +bool batadv_frag_skb_buffer(struct sk_buff **skb, + struct batadv_orig_node *orig_node); + +#endif /* _NET_BATMAN_ADV_FRAGMENTATION_H_ */ diff --git a/main.c b/main.c index a93328f..b633de1 100644 --- a/main.c +++ b/main.c @@ -32,6 +32,7 @@ #include "vis.h" #include "hash.h" #include "bat_algo.h" +#include "fragmentation.h"

/* List manipulations on hardif_list have to be rtnl_lock()'ed, @@ -280,6 +281,8 @@ static void batadv_recv_handler_init(void) batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet; /* vis packet */ batadv_rx_handler[BATADV_VIS] = batadv_recv_vis_packet; + /* Fragmented packets */ + batadv_rx_handler[BATADV_FRAG] = batadv_recv_frag_packet; /* Translation table query (request or response) */ batadv_rx_handler[BATADV_TT_QUERY] = batadv_recv_tt_query; /* Roaming advertisement */ diff --git a/main.h b/main.h index f9a3115..d55200d 100644 --- a/main.h +++ b/main.h @@ -116,6 +116,9 @@ enum batadv_uev_type { };

#define BATADV_GW_THRESHOLD 50 +#define BATADV_FRAG_BUFFER_COUNT 8 +#define BATADV_FRAG_MAX_FRAGMENTS 16 +#define BATADV_FRAG_TIMEOUT 10000

/* Debug Messages */ #ifdef pr_fmt diff --git a/originator.c b/originator.c index 6ebf771..f3463a5 100644 --- a/originator.c +++ b/originator.c @@ -26,6 +26,7 @@ #include "hard-interface.h" #include "soft-interface.h" #include "bridge_loop_avoidance.h" +#include "fragmentation.h"

static void batadv_purge_orig(struct work_struct *work);

@@ -137,6 +138,7 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu)

spin_unlock_bh(&orig_node->neigh_list_lock);

+ batadv_frag_clear_orig(orig_node); batadv_tt_global_del_orig(orig_node->bat_priv, orig_node, "originator timed out");

@@ -192,7 +194,7 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv, const uint8_t *addr) { struct batadv_orig_node *orig_node; - int size; + int size, i; int hash_added; unsigned long reset_time;

@@ -242,6 +244,12 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv, size = bat_priv->num_ifaces * sizeof(uint8_t); orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);

+ for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) { + INIT_HLIST_HEAD(&orig_node->fragments[i].head); + spin_lock_init(&orig_node->fragments[i].lock); + orig_node->fragments[i].size = 0; + } + if (!orig_node->bcast_own_sum) goto free_bcast_own;

@@ -367,6 +375,8 @@ static void _batadv_purge_orig(struct batadv_priv *bat_priv) batadv_orig_node_free_ref(orig_node); continue; } + + batadv_frag_check_orig(orig_node); } spin_unlock_bh(list_lock); } diff --git a/packet.h b/packet.h index ce6e502..5f7ea63 100644 --- a/packet.h +++ b/packet.h @@ -58,6 +58,15 @@ enum batadv_vis_packettype { BATADV_VIS_TYPE_CLIENT_UPDATE = 1, };

+/** + * enum batadv_frag_flags - flags for fragments. + * @BATADV_FRAG_NO_FLAGS: No flags are set. + * @BATADV_FRAG_LAST: Last fragment in a set of fragments. + */ +enum batadv_frag_flags { + BATADV_FRAG_LAST = BIT(0), +}; + /* TT_QUERY subtypes */ #define BATADV_TT_QUERY_TYPE_MASK 0x3

@@ -155,6 +164,26 @@ struct batadv_unicast_packet { uint8_t dest[ETH_ALEN]; } __packed;

+/** + * struct batadv_frag_packet - Network structure for fragments. + * @header: Common batman-adv header with type, compatibility version, and ttl. + * @dest: Final destination used when routing fragments. + * @orig: Originator of the fragment used when merging the packet. + * @no: Fragment number within this sequence. + * @reserved: Unused + * @seqno: Sequence identification. + * @total_size: Size of the merged packet. + */ +struct batadv_frag_packet { + struct batadv_header header; + uint8_t dest[ETH_ALEN]; + uint8_t orig[ETH_ALEN]; + uint8_t no:4; + uint8_t reserved:4; + __be16 seqno; + __be16 total_size; +} __packed; + struct batadv_bcast_packet { struct batadv_header header; uint8_t reserved; diff --git a/routing.c b/routing.c index ca4847e..42d980b 100644 --- a/routing.c +++ b/routing.c @@ -27,6 +27,7 @@ #include "originator.h" #include "vis.h" #include "bridge_loop_avoidance.h" +#include "fragmentation.h"

static int batadv_route_unicast_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if); @@ -960,6 +961,64 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, return batadv_route_unicast_packet(skb, recv_if); }

+/** + * batadv_recv_frag_packet() - Process received fragment. + * @skb: The received fragment. + * @recv_if: Interface that the skb is received on. + * + * This function does one of the three following things: 1) Forward fragment, if + * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till + * lack further fragments; 3) Merge fragments, if we have all needed parts. + * + * Returns NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise. + */ +int batadv_recv_frag_packet(struct sk_buff *skb, + struct batadv_hard_iface *recv_if) +{ + struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); + struct batadv_orig_node *orig_node_src = NULL; + struct batadv_frag_packet *packet; + int ret = NET_RX_DROP; + + if (batadv_check_unicast_packet(skb, sizeof(*packet)) < 0) + goto out; + + packet = (struct batadv_frag_packet *)skb->data; + orig_node_src = batadv_orig_hash_find(bat_priv, packet->orig); + if (!orig_node_src) + goto out; + + /* Route the fragment if it is not for us and too big to be merged. */ + if (!batadv_is_my_mac(packet->dest) && + batadv_frag_skb_fwd(skb, recv_if, orig_node_src)) { + ret = NET_RX_SUCCESS; + goto out; + } + + batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_RX); + batadv_add_counter(bat_priv, BATADV_CNT_FRAG_RX_BYTES, + skb->len + ETH_HLEN); + + /* Add fragment to buffer and merge if possible. */ + if (!batadv_frag_skb_buffer(&skb, orig_node_src)) + goto out; + + /* Deliver merged packet to the appropriate handler, if it was + * merged + */ + if (skb) + batadv_batman_skb_recv(skb, recv_if->net_dev, + &recv_if->batman_adv_ptype, NULL); + + ret = NET_RX_SUCCESS; + +out: + if (orig_node_src) + batadv_orig_node_free_ref(orig_node_src); + + return ret; +} + int batadv_recv_bcast_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if) { diff --git a/routing.h b/routing.h index 9262279..2eb1578 100644 --- a/routing.h +++ b/routing.h @@ -33,6 +33,8 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if); int batadv_recv_ucast_frag_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if); +int batadv_recv_frag_packet(struct sk_buff *skb, + struct batadv_hard_iface *iface); int batadv_recv_bcast_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if); int batadv_recv_vis_packet(struct sk_buff *skb, diff --git a/soft-interface.c b/soft-interface.c index fbec8a4..df0bedc 100644 --- a/soft-interface.c +++ b/soft-interface.c @@ -546,6 +546,10 @@ static const struct { { "mgmt_tx_bytes" }, { "mgmt_rx" }, { "mgmt_rx_bytes" }, + { "frag_rx" }, + { "frag_rx_bytes" }, + { "frag_fwd" }, + { "frag_fwd_bytes" }, { "tt_request_tx" }, { "tt_request_rx" }, { "tt_response_tx" }, diff --git a/types.h b/types.h index 2ed82ca..477f87a 100644 --- a/types.h +++ b/types.h @@ -45,6 +45,34 @@ struct batadv_hard_iface { };

/** + * struct batadv_frag_table_entry - Head in the fragment buffer table. + * @head: Head of list with fragments. + * @lock: Lock to protect the list of fragments. + * @timestamp: Time (jiffie) of last received fragment. + * @seqno: Sequence number of the fragments in the list. + * @size: Accumulated size of packets in list. + */ +struct batadv_frag_table_entry { + struct hlist_head head; + spinlock_t lock; /* Protects head */ + unsigned long timestamp; + uint16_t seqno; + uint16_t size; +}; + +/** + * struct batadv_frag_list_entry - Entry in a list of fragments. + * @list: List node information + * @skb: Fragment + * @no: Fragment number in the set. + */ +struct batadv_frag_list_entry { + struct hlist_node list; + struct sk_buff *skb; + uint8_t no; +}; + +/** * struct batadv_orig_node - structure for orig_list maintaining nodes of mesh * @primary_addr: hosts primary interface address * @last_seen: when last packet from this node was received @@ -105,6 +133,7 @@ struct batadv_orig_node { spinlock_t tt_list_lock; /* protects tt_list */ atomic_t bond_candidates; struct list_head bond_list; + struct batadv_frag_table_entry fragments[BATADV_FRAG_BUFFER_COUNT]; };

struct batadv_gw_node { @@ -156,6 +185,10 @@ enum batadv_counters { BATADV_CNT_MGMT_TX_BYTES, BATADV_CNT_MGMT_RX, BATADV_CNT_MGMT_RX_BYTES, + BATADV_CNT_FRAG_RX, + BATADV_CNT_FRAG_RX_BYTES, + BATADV_CNT_FRAG_FWD, + BATADV_CNT_FRAG_FWD_BYTES, BATADV_CNT_TT_REQUEST_TX, BATADV_CNT_TT_REQUEST_RX, BATADV_CNT_TT_RESPONSE_TX,

The size of the local translation table should not increase the maximum packet size, which is determined by the lowest MTU of hard interfaces and the maximum number of fragments.

This patch adds a check before adding new entries to the table and a new check to remove entries if the MTU decreases.

Signed-off-by: Martin Hundebøll martin@hundeboll.net --- fragmentation.h | 22 +++++++ hard-interface.c | 26 +++++--- soft-interface.c | 8 ++- translation-table.c | 186 +++++++++++++++++++++++++++++++++++++++++++--------- translation-table.h | 3 +- types.h | 3 + 6 files changed, 205 insertions(+), 43 deletions(-)

diff --git a/fragmentation.h b/fragmentation.h index ed85d97..0b95008 100644 --- a/fragmentation.h +++ b/fragmentation.h @@ -31,4 +31,26 @@ bool batadv_frag_send_packet(struct sk_buff *skb, struct batadv_orig_node *orig_node, struct batadv_neigh_node *neigh_node);

+/** + * batadv_frag_max_packet_size() - Get maximum packet size with fragmentation. + * @bat_priv: Batman-adv private data. + * + * Returns the maximum size of one unicast packet if fragmentation is disabled + * or maximum size of one fragmented packet if fragmentation is enabled. + */ +static inline int batadv_frag_max_packet_size(struct batadv_priv *bat_priv) +{ + int mtu = atomic_read(&bat_priv->min_mtu); + + /* Return mtu for one packet if fragmentation is disabled. */ + if (!atomic_read(&bat_priv->fragmentation)) + return mtu - ETH_HLEN; + + /* Determine max size with multiple fragments */ + mtu = min_t(int, mtu, BATADV_FRAG_MAX_FRAG_SIZE); + mtu -= sizeof(struct batadv_frag_packet); + mtu -= ETH_HLEN; + return mtu*BATADV_FRAG_MAX_FRAGMENTS; +} + #endif /* _NET_BATMAN_ADV_FRAGMENTATION_H_ */ diff --git a/hard-interface.c b/hard-interface.c index d112fd6..80b9465 100644 --- a/hard-interface.c +++ b/hard-interface.c @@ -180,16 +180,11 @@ static void batadv_check_known_mac_addr(const struct net_device *net_dev)

int batadv_hardif_min_mtu(struct net_device *soft_iface) { - const struct batadv_priv *bat_priv = netdev_priv(soft_iface); + struct batadv_priv *bat_priv = netdev_priv(soft_iface); const struct batadv_hard_iface *hard_iface; - /* allow big frames if all devices are capable to do so - * (have MTU > 1500 + BAT_HEADER_LEN) - */ int min_mtu = ETH_DATA_LEN;

- if (atomic_read(&bat_priv->fragmentation)) - goto out; - + /* Check if any interface has lower MTU than the current minimum MTU. */ rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { if ((hard_iface->if_status != BATADV_IF_ACTIVE) && @@ -204,8 +199,16 @@ int batadv_hardif_min_mtu(struct net_device *soft_iface) min_mtu); } rcu_read_unlock(); -out: - return min_mtu; + + /* Update current minimum MTU. */ + atomic_set(&bat_priv->min_mtu, min_mtu); + + if (atomic_read(&bat_priv->fragmentation)) + /* Allow big frames if fragmentation is enabled. */ + return ETH_DATA_LEN; + else + /* Limit frame size if fragmentation is disabled. */ + return min_mtu; }

/* adjusts the MTU if a new interface with a smaller MTU appeared. */ @@ -216,6 +219,11 @@ void batadv_update_min_mtu(struct net_device *soft_iface) min_mtu = batadv_hardif_min_mtu(soft_iface); if (soft_iface->mtu != min_mtu) soft_iface->mtu = min_mtu; + + /* Check if the local translate table should be cleaned up to match a + * new (and smaller) MTU. + */ + batadv_tt_check_mtu(soft_iface); }

static void diff --git a/soft-interface.c b/soft-interface.c index c21f1fc..4a9dfbd 100644 --- a/soft-interface.c +++ b/soft-interface.c @@ -171,8 +171,10 @@ static int batadv_interface_tx(struct sk_buff *skb, if (batadv_bla_tx(bat_priv, skb, vid)) goto dropped;

- /* Register the client MAC in the transtable */ - batadv_tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif); + /* Register the client MAC in the transtable. Drop packet if the entry + * wasn't added. */ + if (!batadv_tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif)) + goto dropped;

/* don't accept stp packets. STP does not help in meshes. * better use the bridge loop avoidance ... @@ -422,12 +424,14 @@ struct net_device *batadv_softif_create(const char *name) atomic_set(&bat_priv->fragmentation, 1); atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN); atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN); + atomic_set(&bat_priv->min_mtu, ETH_DATA_LEN);

atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE); atomic_set(&bat_priv->bcast_seqno, 1); atomic_set(&bat_priv->tt.vn, 0); atomic_set(&bat_priv->tt.local_changes, 0); atomic_set(&bat_priv->tt.ogm_append_cnt, 0); + atomic_set(&bat_priv->tt.reduced_table, 0); #ifdef CONFIG_BATMAN_ADV_BLA atomic_set(&bat_priv->bla.num_requests, 0); #endif diff --git a/translation-table.c b/translation-table.c index 2cee8b2..2b6c42b 100644 --- a/translation-table.c +++ b/translation-table.c @@ -26,6 +26,7 @@ #include "originator.h" #include "routing.h" #include "bridge_loop_avoidance.h" +#include "fragmentation.h"

#include <linux/crc16.h>

@@ -237,7 +238,7 @@ static int batadv_tt_local_init(struct batadv_priv *bat_priv) return 0; }

-void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, +bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, int ifindex) { struct batadv_priv *bat_priv = netdev_priv(soft_iface); @@ -246,7 +247,8 @@ void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, struct hlist_head *head; struct hlist_node *node; struct batadv_tt_orig_list_entry *orig_entry; - int hash_added; + int hash_added, size = sizeof(struct batadv_tt_query_packet); + bool ret = false;

tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);

@@ -254,6 +256,19 @@ void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, tt_local_entry->last_seen = jiffies; /* possibly unset the BATADV_TT_CLIENT_PENDING flag */ tt_local_entry->common.flags &= ~BATADV_TT_CLIENT_PENDING; + ret = true; + goto out; + } + + /* Ignore it if we cannot send it in a full table response. */ + size += batadv_tt_len(atomic_read(&bat_priv->tt.local_entry_num) + 1); + if (size > batadv_frag_max_packet_size(bat_priv)) { + if (!net_ratelimit()) + goto out; + + batadv_info(soft_iface, + "Local translation table size (%i) exceeds maximum packet size (%i); Ignoring new local tt entry: %pM\n", + size, batadv_frag_max_packet_size(bat_priv), addr); goto out; }

@@ -318,11 +333,16 @@ void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM; tt_global_entry->roam_at = jiffies; } + + ret = true; + out: if (tt_local_entry) batadv_tt_local_entry_free_ref(tt_local_entry); if (tt_global_entry) batadv_tt_global_entry_free_ref(tt_global_entry); + + return ret; }

static void batadv_tt_realloc_packet_buff(unsigned char **packet_buff, @@ -520,8 +540,9 @@ out: batadv_tt_local_entry_free_ref(tt_local_entry); }

-static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv, - struct hlist_head *head) +static void +batadv_tt_local_purge_list(struct batadv_priv *bat_priv, + struct hlist_head *head) { struct batadv_tt_local_entry *tt_local_entry; struct batadv_tt_common_entry *tt_common_entry; @@ -544,7 +565,8 @@ static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv, continue;

batadv_tt_local_set_pending(bat_priv, tt_local_entry, - BATADV_TT_CLIENT_DEL, "timed out"); + BATADV_TT_CLIENT_DEL, + "timed out"); } }

@@ -1448,7 +1470,6 @@ static int batadv_tt_global_valid(const void *entry_ptr, static struct sk_buff * batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn, struct batadv_hashtable *hash, - struct batadv_hard_iface *primary_if, int (*valid_cb)(const void *, const void *), void *cb_data) { @@ -1458,17 +1479,11 @@ batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn, struct hlist_node *node; struct hlist_head *head; struct sk_buff *skb = NULL; - uint16_t tt_tot, tt_count; + uint16_t tt_count = 0; ssize_t tt_query_size = sizeof(struct batadv_tt_query_packet); uint32_t i; size_t len;

- if (tt_query_size + tt_len > primary_if->soft_iface->mtu) { - tt_len = primary_if->soft_iface->mtu - tt_query_size; - tt_len -= tt_len % sizeof(struct batadv_tt_change); - } - tt_tot = tt_len / sizeof(struct batadv_tt_change); - len = tt_query_size + tt_len; skb = dev_alloc_skb(len + ETH_HLEN); if (!skb) @@ -1479,7 +1494,6 @@ batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn, tt_response->ttvn = ttvn;

tt_change = (struct batadv_tt_change *)(skb->data + tt_query_size); - tt_count = 0;

rcu_read_lock(); for (i = 0; i < hash->size; i++) { @@ -1487,9 +1501,6 @@ batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn,

hlist_for_each_entry_rcu(tt_common_entry, node, head, hash_entry) { - if (tt_count == tt_tot) - break; - if ((valid_cb) && (!valid_cb(tt_common_entry, cb_data))) continue;

@@ -1582,9 +1593,9 @@ static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv, struct batadv_tt_query_packet *tt_request) { + struct batadv_hard_iface *iface; struct batadv_orig_node *req_dst_orig_node = NULL; struct batadv_orig_node *res_dst_orig_node = NULL; - struct batadv_hard_iface *primary_if = NULL; uint8_t orig_ttvn, req_ttvn, ttvn; int ret = false; unsigned char *tt_buff; @@ -1609,8 +1620,8 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv, if (!res_dst_orig_node) goto out;

- primary_if = batadv_primary_if_get_selected(bat_priv); - if (!primary_if) + iface = batadv_primary_if_get_selected(bat_priv); + if (!iface) goto out;

orig_ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn); @@ -1658,9 +1669,20 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv, tt_len *= sizeof(struct batadv_tt_change); ttvn = (uint8_t)atomic_read(&req_dst_orig_node->last_ttvn);

+ /* Don't send the response, if larger than fragmented packet. */ + len = sizeof(*tt_response) + tt_len; + if (len > batadv_frag_max_packet_size(bat_priv)) { + if (!net_ratelimit()) + goto out; + + batadv_info(iface->soft_iface, + "Ignoring TT_REQUEST from %pM; Response size exceeds max packet size.\n", + res_dst_orig_node->orig); + goto out; + } + skb = batadv_tt_response_fill_table(tt_len, ttvn, bat_priv->tt.global_hash, - primary_if, batadv_tt_global_valid, req_dst_orig_node); if (!skb) @@ -1697,8 +1719,6 @@ out: batadv_orig_node_free_ref(res_dst_orig_node); if (req_dst_orig_node) batadv_orig_node_free_ref(req_dst_orig_node); - if (primary_if) - batadv_hardif_free_ref(primary_if); if (!ret) kfree_skb(skb); return ret; @@ -1775,9 +1795,14 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv, tt_len *= sizeof(struct batadv_tt_change); ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);

+ /* If we have an inconsistent table due to reduced MTU, we + * increase ttvn temporarily. + * */ + if (atomic_read(&bat_priv->tt.reduced_table)) + ttvn++; + skb = batadv_tt_response_fill_table(tt_len, ttvn, bat_priv->tt.local_hash, - primary_if, batadv_tt_local_valid_entry, NULL); if (!skb) @@ -2195,8 +2220,73 @@ out: return changed_num; }

+/** + * batadv_tt_local_test_pending() - Callback to test pending flag of an entry. + * @bat_priv: Batman-adv private data. + * @entry: Local entry to be deleted. + * @data: Not used + * + * This callback is made to be passed as a purge function to + * batadv_tt_local_purge_pending(), where it is called with every entry. It + * checks if the entry is flagged as pending and frees it if so. + */ +static int batadv_tt_local_test_pending(struct batadv_priv *bat_priv, + void *entry, void *data) +{ + struct batadv_tt_common_entry *tt_common_entry = entry; + + if (!(tt_common_entry->flags & BATADV_TT_CLIENT_PENDING)) + return 0; + + batadv_dbg(BATADV_DBG_TT, bat_priv, + "Deleting local tt entry (%pM): pending\n", + tt_common_entry->addr); + + return 1; +} + +/** + * batadv_tt_local_test_timeout() - Callback to test timeout of an entry. + * @bat_priv: Batman-adv private data. + * @entry: Local entry to be deleted. + * @data: Pointer to timeout in milliseconds to check the entry with. + * + * This callback is made to be passed as a purge function to + * batadv_tt_local_purge_pending(), where it is called with every entry. It + * checks if the entry is timed out and frees it immediately, instead of + * flagging it as pending, and then adds the removal to the changeset. + */ +static int batadv_tt_local_test_timeout(struct batadv_priv *bat_priv, + void *entry, void *data) +{ + struct batadv_tt_common_entry *tt_common_entry = entry; + struct batadv_tt_local_entry *tt_local_entry; + int *timeout = data; + + if (tt_common_entry->flags & BATADV_TT_CLIENT_PENDING) + return 0; + + tt_local_entry = container_of(tt_common_entry, + struct batadv_tt_local_entry, common); + + if (!batadv_has_timed_out(tt_local_entry->last_seen, *timeout)) + return 0; + + batadv_dbg(BATADV_DBG_TT, bat_priv, + "Deleting local tt entry (%pM): forced\n", + tt_common_entry->addr); + + batadv_tt_local_event(bat_priv, tt_local_entry->common.addr, + BATADV_TT_CLIENT_DEL); + + return 1; +} + /* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */ -static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv) +static void batadv_tt_local_purge_pending(struct batadv_priv *bat_priv, + int (test)(struct batadv_priv *, + void *, void *), + void *data) { struct batadv_hashtable *hash = bat_priv->tt.local_hash; struct batadv_tt_common_entry *tt_common; @@ -2216,13 +2306,9 @@ static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv) spin_lock_bh(list_lock); hlist_for_each_entry_safe(tt_common, node, node_tmp, head, hash_entry) { - if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING)) + if (!test(bat_priv, tt_common, data)) continue;

- batadv_dbg(BATADV_DBG_TT, bat_priv, - "Deleting local tt entry (%pM): pending\n", - tt_common->addr); - atomic_dec(&bat_priv->tt.local_entry_num); hlist_del_rcu(node); tt_local = container_of(tt_common, @@ -2249,11 +2335,13 @@ static int batadv_tt_commit_changes(struct batadv_priv *bat_priv,

/* all reset entries have to be counted as local entries */ atomic_add(changed_num, &bat_priv->tt.local_entry_num); - batadv_tt_local_purge_pending_clients(bat_priv); + batadv_tt_local_purge_pending(bat_priv, + batadv_tt_local_test_pending, NULL); bat_priv->tt.local_crc = batadv_tt_local_crc(bat_priv);

/* Increment the TTVN only once per OGM interval */ atomic_inc(&bat_priv->tt.vn); + atomic_set(&bat_priv->tt.reduced_table, 0); batadv_dbg(BATADV_DBG_TT, bat_priv, "Local changes committed, updating to ttvn %u\n", (uint8_t)atomic_read(&bat_priv->tt.vn)); @@ -2430,3 +2518,39 @@ bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv, out: return ret; } + +/** + * batadv_tt_check_mtu() - Make local table fit a fragmented packet. + * @bat_priv: Private data + * @mtu: Lowest MTU of local interfaces. + * + * Remove entries older than 'timeout' and half timeout if more entries needs + * to be removed. + */ +void batadv_tt_check_mtu(struct net_device *soft_iface) +{ + struct batadv_priv *bat_priv = netdev_priv(soft_iface); + int max_size = batadv_frag_max_packet_size(bat_priv); + int num = atomic_read(&bat_priv->tt.local_entry_num); + int hdr_size = sizeof(struct batadv_tt_query_packet); + int table_size = hdr_size + batadv_tt_len(num); + int timeout = BATADV_TT_LOCAL_TIMEOUT/2; + + while (table_size > max_size) { + batadv_tt_local_purge_pending(bat_priv, + batadv_tt_local_test_timeout, + &timeout); + + num = atomic_read(&bat_priv->tt.local_entry_num); + table_size = hdr_size + batadv_tt_len(num); + timeout /= 2; + atomic_set(&bat_priv->tt.reduced_table, 1); + + if (!net_ratelimit()) + continue; + + batadv_info(soft_iface, + "Forced to purge local tt entries to fit new fragment MTU (%i)\n", + max_size); + } +} diff --git a/translation-table.h b/translation-table.h index 811fffd..380ad86 100644 --- a/translation-table.h +++ b/translation-table.h @@ -22,7 +22,7 @@

int batadv_tt_len(int changes_num); int batadv_tt_init(struct batadv_priv *bat_priv); -void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, +bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr, int ifindex); void batadv_tt_local_remove(struct batadv_priv *bat_priv, const uint8_t *addr, const char *message, @@ -62,5 +62,6 @@ bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv, bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node, const unsigned char *addr); +void batadv_tt_check_mtu(struct net_device *soft_iface);

#endif /* _NET_BATMAN_ADV_TRANSLATION_TABLE_H_ */ diff --git a/types.h b/types.h index 0450b57..fa17288 100644 --- a/types.h +++ b/types.h @@ -211,6 +211,7 @@ enum batadv_counters { * @changes_list: tracks tt local changes within an originator interval * @req_list: list of pending tt_requests * @local_crc: Checksum of the local table, recomputed before sending a new OGM + * @reduced_table: Flag to make own tt_responses carry an increased ttvn. */ struct batadv_priv_tt { atomic_t vn; @@ -231,6 +232,7 @@ struct batadv_priv_tt { int16_t last_changeset_len; spinlock_t last_changeset_lock; /* protects last_changeset */ struct delayed_work work; + atomic_t reduced_table; };

#ifdef CONFIG_BATMAN_ADV_BLA @@ -281,6 +283,7 @@ struct batadv_priv { atomic_t bcast_seqno; atomic_t bcast_queue_left; atomic_t batman_queue_left; + atomic_t min_mtu; char num_ifaces; struct batadv_debug_log *debug_log; struct kobject *mesh_obj;