The current unicast packet type does not contain the orig source address. This patches add a new unicast packet (called UNICAST_4ADDR) which provides two new fields: the originator source address and the subtype (the type of the data contained in the packet payload). The former is useful to identify the node which injected the packet into the network and the latter is useful to avoid creating new unicast packet types in the future: a macro defining a new subtype will be enough.

Signed-off-by: Antonio Quartulli ordex@autistici.org --- net/batman-adv/main.c | 2 + net/batman-adv/packet.h | 37 ++++++++--- net/batman-adv/routing.c | 8 ++- net/batman-adv/soft-interface.c | 2 +- net/batman-adv/unicast.c | 134 +++++++++++++++++++++++++++++++++++----- net/batman-adv/unicast.h | 32 +++++++++- 6 files changed, 189 insertions(+), 26 deletions(-)

diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index f9bcfa1..afc07a8 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -300,6 +300,8 @@ static void batadv_recv_handler_init(void)

/* batman icmp packet */ batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet; + /* unicast with 4 addresses packet */ + batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet; /* unicast packet */ batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet; /* fragmented unicast packet */ diff --git a/net/batman-adv/packet.h b/net/batman-adv/packet.h index 2d23a14..72d7331 100644 --- a/net/batman-adv/packet.h +++ b/net/batman-adv/packet.h @@ -23,14 +23,23 @@ #define BATADV_ETH_P_BATMAN 0x4305 /* unofficial/not registered Ethertype */

enum batadv_packettype { - BATADV_IV_OGM = 0x01, - BATADV_ICMP = 0x02, - BATADV_UNICAST = 0x03, - BATADV_BCAST = 0x04, - BATADV_VIS = 0x05, - BATADV_UNICAST_FRAG = 0x06, - BATADV_TT_QUERY = 0x07, - BATADV_ROAM_ADV = 0x08, + BATADV_IV_OGM = 0x01, + BATADV_ICMP = 0x02, + BATADV_UNICAST = 0x03, + BATADV_BCAST = 0x04, + BATADV_VIS = 0x05, + BATADV_UNICAST_FRAG = 0x06, + BATADV_TT_QUERY = 0x07, + BATADV_ROAM_ADV = 0x08, + BATADV_UNICAST_4ADDR = 0x09, +}; + +/** + * enum batadv_subtype - packet subtype for unicast4addr + * @BATADV_P_DATA: user payload + */ +enum batadv_subtype { + BATADV_P_DATA = 0x01, };

/* this file is included by batctl which needs these defines */ @@ -161,6 +170,18 @@ struct batadv_unicast_packet { uint8_t dest[ETH_ALEN]; } __packed;

+/** + * struct batadv_unicast_4addr_packet - extended unicast packet + * @u: common unicast packet header + * @src: address of the source + * @subtype: packet subtype + */ +struct batadv_unicast_4addr_packet { + struct batadv_unicast_packet u; + uint8_t src[ETH_ALEN]; + uint8_t subtype; +} __packed; + struct batadv_unicast_frag_packet { struct batadv_header header; uint8_t ttvn; /* destination translation table version number */ diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 46dd5b4..859679b 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -986,14 +986,18 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, struct batadv_unicast_packet *unicast_packet; int hdr_size = sizeof(*unicast_packet);

+ unicast_packet = (struct batadv_unicast_packet *)skb->data; + + /* the caller function should have already pulled 2 bytes */ + if (unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR) + hdr_size = sizeof(struct batadv_unicast_4addr_packet); + if (batadv_check_unicast_packet(skb, hdr_size) < 0) return NET_RX_DROP;

if (!batadv_check_unicast_ttvn(bat_priv, skb)) return NET_RX_DROP;

- unicast_packet = (struct batadv_unicast_packet *)skb->data; - /* packet for me */ if (batadv_is_my_mac(unicast_packet->dest)) { batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 22bc651..2f123a1 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -260,7 +260,7 @@ static int batadv_interface_tx(struct sk_buff *skb, goto dropped; }

- ret = batadv_unicast_send_skb(skb, bat_priv); + ret = batadv_unicast_send_skb(bat_priv, skb); if (ret != 0) goto dropped_freed; } diff --git a/net/batman-adv/unicast.c b/net/batman-adv/unicast.c index f397232..1df22c5 100644 --- a/net/batman-adv/unicast.c +++ b/net/batman-adv/unicast.c @@ -291,7 +291,110 @@ out: return ret; }

-int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv) +/** + * batadv_unicast_push_and_fill_skb - extends the buffer and initializes the + * common fields for unicast packets + * @skb: packet + * @hdr_size: amount of bytes to push at the beginning of the skb + * @orig_node: the destination node + * + * Returns false if the buffer extension was not possible or true otherwise + */ +static bool batadv_unicast_push_and_fill_skb(struct sk_buff *skb, int hdr_size, + struct batadv_orig_node *orig_node) +{ + struct batadv_unicast_packet *unicast_packet; + uint8_t ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn); + + if (batadv_skb_head_push(skb, hdr_size) < 0) + return false; + + unicast_packet = (struct batadv_unicast_packet *)skb->data; + unicast_packet->header.version = BATADV_COMPAT_VERSION; + /* batman packet type: unicast */ + unicast_packet->header.packet_type = BATADV_UNICAST; + /* set unicast ttl */ + unicast_packet->header.ttl = BATADV_TTL; + /* copy the destination for faster routing */ + memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN); + /* set the destination tt version number */ + unicast_packet->ttvn = ttvn; + + return true; +} + +/** + * batadv_unicast_prepare_skb - encapsulate an skb with a unicast header + * @skb: the skb containing the payload to encapsulate + * @orig_node: the destination node + * + * Returns false if the payload could not be encapsulated or true otherwise + */ +static bool batadv_unicast_prepare_skb(struct sk_buff *skb, + struct batadv_orig_node *orig_node) +{ + size_t uni_size = sizeof(struct batadv_unicast_packet); + return batadv_unicast_push_and_fill_skb(skb, uni_size, orig_node); +} + +/** + * batadv_unicast_4addr_prepare_skb - encapsulate an skb with a unicast4addr + * header + * @bat_priv: the bat priv with all the soft interface information + * @skb: the skb containing the payload to encapsulate + * @orig_node: the destination node + * @packet_subtype: the batman 4addr packet subtype to use + * + * Returns false if the payload could not be encapsulated or true otherwise + */ +static bool batadv_unicast_4addr_prepare_skb(struct batadv_priv *bat_priv, + struct sk_buff *skb, + struct batadv_orig_node *orig, + int packet_subtype) +{ + struct batadv_hard_iface *primary_if; + struct batadv_unicast_4addr_packet *unicast_4addr_packet; + bool ret = false; + + primary_if = batadv_primary_if_get_selected(bat_priv); + if (!primary_if) + goto out; + + /* pull the header space and fill the unicast_packet substructure. + * We can do that because the first member of the unicast_4addr_packet + * is of type struct unicast_packet + */ + if (!batadv_unicast_push_and_fill_skb(skb, + sizeof(*unicast_4addr_packet), + orig)) + goto out; + + unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; + unicast_4addr_packet->u.header.packet_type = BATADV_UNICAST_4ADDR; + memcpy(unicast_4addr_packet->src, primary_if->net_dev->dev_addr, + ETH_ALEN); + unicast_4addr_packet->subtype = packet_subtype; + + ret = true; +out: + if (primary_if) + batadv_hardif_free_ref(primary_if); + return ret; +} + +/** + * batadv_unicast_generic_send_skb - send an skb as unicast + * @bat_priv: the bat priv with all the soft interface information + * @skb: payload to send + * @packet_type: the batman unicast packet type to use + * @packet_subtype: the batman packet subtype. It is ignored if packet_type is + * not BATADV_UNICAT_4ADDR + * + * Returns 1 in case of error or 0 otherwise + */ +int batadv_unicast_generic_send_skb(struct batadv_priv *bat_priv, + struct sk_buff *skb, int packet_type, + int packet_subtype) { struct ethhdr *ethhdr = (struct ethhdr *)skb->data; struct batadv_unicast_packet *unicast_packet; @@ -324,21 +427,23 @@ find_router: if (!neigh_node) goto out;

- if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0) + switch (packet_type) { + case BATADV_UNICAST: + batadv_unicast_prepare_skb(skb, orig_node); + break; + case BATADV_UNICAST_4ADDR: + batadv_unicast_4addr_prepare_skb(bat_priv, skb, orig_node, + packet_subtype); + break; + default: + /* this function supports UNICAST and UNICAST_4ADDR only. It + * should never be invoked with any other packet type + */ goto out; + }

unicast_packet = (struct batadv_unicast_packet *)skb->data;

- unicast_packet->header.version = BATADV_COMPAT_VERSION; - /* batman packet type: unicast */ - unicast_packet->header.packet_type = BATADV_UNICAST; - /* set unicast ttl */ - unicast_packet->header.ttl = BATADV_TTL; - /* copy the destination for faster routing */ - memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN); - /* set the destination tt version number */ - unicast_packet->ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn); - /* inform the destination node that we are still missing a correct route * for this client. The destination will receive this packet and will * try to reroute it because the ttvn contained in the header is less @@ -348,7 +453,9 @@ find_router: unicast_packet->ttvn = unicast_packet->ttvn - 1;

dev_mtu = neigh_node->if_incoming->net_dev->mtu; - if (atomic_read(&bat_priv->fragmentation) && + /* fragmentation mechanism only works for UNICAST (now) */ + if (packet_type == BATADV_UNICAST && + atomic_read(&bat_priv->fragmentation) && data_len + sizeof(*unicast_packet) > dev_mtu) { /* send frag skb decreases ttl */ unicast_packet->header.ttl++; @@ -360,7 +467,6 @@ find_router:

batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr); ret = 0; - goto out;

out: if (neigh_node) diff --git a/net/batman-adv/unicast.h b/net/batman-adv/unicast.h index 1c46e2e..a88ed29 100644 --- a/net/batman-adv/unicast.h +++ b/net/batman-adv/unicast.h @@ -29,10 +29,40 @@ int batadv_frag_reassemble_skb(struct sk_buff *skb, struct batadv_priv *bat_priv, struct sk_buff **new_skb); void batadv_frag_list_free(struct list_head *head); -int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv); int batadv_frag_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv, struct batadv_hard_iface *hard_iface, const uint8_t dstaddr[]); +int batadv_unicast_generic_send_skb(struct batadv_priv *bat_priv, + struct sk_buff *skb, int packet_type, + int packet_subtype); + + +/** + * batadv_unicast_send_skb - send the skb encapsulated in a unicast packet + * @bat_priv: the bat priv with all the soft interface information + * @skb: the payload to send + */ +static inline int batadv_unicast_send_skb(struct batadv_priv *bat_priv, + struct sk_buff *skb) +{ + return batadv_unicast_generic_send_skb(bat_priv, skb, BATADV_UNICAST, + 0); +} + +/** + * batadv_unicast_send_skb - send the skb encapsulated in a unicast4addr packet + * @bat_priv: the bat priv with all the soft interface information + * @skb: the payload to send + * @packet_subtype: the batman 4addr packet subtype to use + */ +static inline int batadv_unicast_4addr_send_skb(struct batadv_priv *bat_priv, + struct sk_buff *skb, + int packet_subtype) +{ + return batadv_unicast_generic_send_skb(bat_priv, skb, + BATADV_UNICAST_4ADDR, + packet_subtype); +}

static inline int batadv_frag_can_reassemble(const struct sk_buff *skb, int mtu) {

A new log level has been added to concentrate messages regarding DAT: ARP snooping, requests, response and DHT related messages. The new log level is named BATADV_DBG_DAT

Signed-off-by: Antonio Quartulli ordex@autistici.org --- Documentation/networking/batman-adv.txt | 3 ++- net/batman-adv/main.h | 4 +++- 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/networking/batman-adv.txt b/Documentation/networking/batman-adv.txt index a173d2a..c1d8204 100644 --- a/Documentation/networking/batman-adv.txt +++ b/Documentation/networking/batman-adv.txt @@ -203,7 +203,8 @@ abled during run time. Following log_levels are defined: 2 - Enable messages related to route added / changed / deleted 4 - Enable messages related to translation table operations 8 - Enable messages related to bridge loop avoidance -15 - enable all messages +16 - Enable messaged related to DAT, ARP snooping and parsing +31 - Enable all messages

The debug output can be changed at runtime using the file /sys/class/net/bat0/mesh/log_level. e.g. diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 897ba6a..c08724a 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -171,6 +171,7 @@ int batadv_algo_seq_print_text(struct seq_file *seq, void *offset); * @BATADV_DBG_ROUTES: route added / changed / deleted * @BATADV_DBG_TT: translation table messages * @BATADV_DBG_BLA: bridge loop avoidance messages + * @BATADV_DBG_DAT: ARP snooping and DAT related messages * @BATADV_DBG_ALL: the union of all the above log levels */ enum batadv_dbg_level { @@ -178,7 +179,8 @@ enum batadv_dbg_level { BATADV_DBG_ROUTES = BIT(1), BATADV_DBG_TT = BIT(2), BATADV_DBG_BLA = BIT(3), - BATADV_DBG_ALL = 15, + BATADV_DBG_DAT = BIT(4), + BATADV_DBG_ALL = 31, };

#ifdef CONFIG_BATMAN_ADV_DEBUG

Since batman-adv cannot inter-operate with the host ARP table, this patch introduces a batman-adv private storage for ARP entries exchanged within DAT. This storage will represent the node local cache in the DAT protocol.

Signed-off-by: Antonio Quartulli ordex@autistici.org --- net/batman-adv/debugfs.c | 15 ++ net/batman-adv/distributed-arp-table.c | 296 +++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 4 + net/batman-adv/main.c | 7 + net/batman-adv/main.h | 1 + net/batman-adv/types.h | 23 +++ 6 files changed, 346 insertions(+)

diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c index bd032bc..ebc5f4d 100644 --- a/net/batman-adv/debugfs.c +++ b/net/batman-adv/debugfs.c @@ -31,6 +31,7 @@ #include "vis.h" #include "icmp_socket.h" #include "bridge_loop_avoidance.h" +#include "distributed-arp-table.h"

static struct dentry *batadv_debugfs;

@@ -280,6 +281,18 @@ static int batadv_bla_backbone_table_open(struct inode *inode,

#endif

+/** + * batadv_dat_cache_open - Prepare file handler for reads from dat_chache + * @inode: inode which was opened + * @file: file handle to be initialized + */ +static int batadv_dat_cache_open(struct inode *inode, struct file *file) +{ + struct net_device *net_dev = (struct net_device *)inode->i_private; + return single_open(file, batadv_dat_cache_seq_print_text, net_dev); +} + + static int batadv_transtable_local_open(struct inode *inode, struct file *file) { struct net_device *net_dev = (struct net_device *)inode->i_private; @@ -319,6 +332,7 @@ static BATADV_DEBUGINFO(bla_claim_table, S_IRUGO, batadv_bla_claim_table_open); static BATADV_DEBUGINFO(bla_backbone_table, S_IRUGO, batadv_bla_backbone_table_open); #endif +static BATADV_DEBUGINFO(dat_cache, S_IRUGO, batadv_dat_cache_open); static BATADV_DEBUGINFO(transtable_local, S_IRUGO, batadv_transtable_local_open); static BATADV_DEBUGINFO(vis_data, S_IRUGO, batadv_vis_data_open); @@ -331,6 +345,7 @@ static struct batadv_debuginfo *batadv_mesh_debuginfos[] = { &batadv_debuginfo_bla_claim_table, &batadv_debuginfo_bla_backbone_table, #endif + &batadv_debuginfo_dat_cache, &batadv_debuginfo_transtable_local, &batadv_debuginfo_vis_data, NULL, diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index ce39e8a..2ef90e3 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -28,6 +28,119 @@ #include "types.h" #include "unicast.h"

+static void batadv_dat_purge(struct work_struct *work); + +/** + * batadv_dat_start_timer - initialise the DAT periodic worker + * @bat_priv: the bat priv with all the soft interface information + */ +static void batadv_dat_start_timer(struct batadv_priv *bat_priv) +{ + INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge); + queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work, + msecs_to_jiffies(10000)); +} + +/** + * batadv_dat_entry_free_ref - decrements the dat_entry refcounter and possibly + * free it + * @dat_entry: the oentry to free + */ +static void batadv_dat_entry_free_ref(struct batadv_dat_entry *dat_entry) +{ + if (atomic_dec_and_test(&dat_entry->refcount)) + kfree_rcu(dat_entry, rcu); +} + +/** + * batadv_dat_to_purge - checks whether a dat_entry has to be purged or not + * @dat_entry: the entry to check + * + * Returns true if the entry has to be purged now, false otherwise + */ +static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry) +{ + return batadv_has_timed_out(dat_entry->last_update, + BATADV_DAT_ENTRY_TIMEOUT); +} + +/** + * __batadv_dat_purge - delete entries from the DAT local storage + * @bat_priv: the bat priv with all the soft interface information + * @to_purge: function in charge to decide whether an entry has to be purged or + * not. This function takes the dat_entry as argument and has to + * returns a boolean value: true is the entry has to be deleted, + * false otherwise + * + * Loops over each entry in the DAT local storage and delete it if and only if + * the to_purge function passed as argument returns true + */ +static void __batadv_dat_purge(struct batadv_priv *bat_priv, + bool (*to_purge)(struct batadv_dat_entry *)) +{ + spinlock_t *list_lock; /* protects write access to the hash lists */ + struct batadv_dat_entry *dat_entry; + struct hlist_node *node, *node_tmp; + struct hlist_head *head; + uint32_t i; + + if (!bat_priv->dat.hash) + return; + + for (i = 0; i < bat_priv->dat.hash->size; i++) { + head = &bat_priv->dat.hash->table[i]; + list_lock = &bat_priv->dat.hash->list_locks[i]; + + spin_lock_bh(list_lock); + hlist_for_each_entry_safe(dat_entry, node, node_tmp, head, + hash_entry) { + /* if an helper function has been passed as parameter, + * ask it if the entry has to be purged or not + */ + if (to_purge && !to_purge(dat_entry)) + continue; + + hlist_del_rcu(node); + batadv_dat_entry_free_ref(dat_entry); + } + spin_unlock_bh(list_lock); + } +} + +/** + * batadv_dat_purge - periodic task that deletes old entries from the local DAT + * hash table + * @work: kernel work struct + */ +static void batadv_dat_purge(struct work_struct *work) +{ + struct delayed_work *delayed_work; + struct batadv_priv_dat *priv_dat; + struct batadv_priv *bat_priv; + + delayed_work = container_of(work, struct delayed_work, work); + priv_dat = container_of(delayed_work, struct batadv_priv_dat, work); + bat_priv = container_of(priv_dat, struct batadv_priv, dat); + + __batadv_dat_purge(bat_priv, batadv_dat_to_purge); + batadv_dat_start_timer(bat_priv); +} + +/** + * batadv_compare_dat - comparing function used in the local DAT hash table + * @node: node in the local table + * @data2: second object to compare the node to + * + * Returns 1 if the two entry are the same, 0 otherwise + */ +static int batadv_compare_dat(const struct hlist_node *node, const void *data2) +{ + const void *data1 = container_of(node, struct batadv_dat_entry, + hash_entry); + + return (memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0); +} + /** * batadv_hash_dat - compute the hash value for an IP address * @data: data to hash @@ -55,6 +168,96 @@ static uint32_t batadv_hash_dat(const void *data, uint32_t size) }

/** + * batadv_dat_entry_hash_find - looks for a given dat_entry in the local hash + * table + * @bat_priv: the bat priv with all the soft interface information + * @ip: search key + * + * Returns the dat_entry if found, NULL otherwise + */ +static struct batadv_dat_entry * +batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip) +{ + struct hlist_head *head; + struct hlist_node *node; + struct batadv_dat_entry *dat_entry, *dat_entry_tmp = NULL; + struct batadv_hashtable *hash = bat_priv->dat.hash; + uint32_t index; + + if (!hash) + return NULL; + + index = batadv_hash_dat(&ip, hash->size); + head = &hash->table[index]; + + rcu_read_lock(); + hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) { + if (dat_entry->ip != ip) + continue; + + if (!atomic_inc_not_zero(&dat_entry->refcount)) + continue; + + dat_entry_tmp = dat_entry; + break; + } + rcu_read_unlock(); + + return dat_entry_tmp; +} + +/** + * batadv_dat_entry_add - add a new dat entry or update it if already exists + * @bat_priv: the bat priv with all the soft interface information + * @ip: ipv4 to add/edit + * @mac_addr: mac address to assign to the given ipv4 + */ +static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip, + uint8_t *mac_addr) +{ + struct batadv_dat_entry *dat_entry; + int hash_added; + + dat_entry = batadv_dat_entry_hash_find(bat_priv, ip); + /* if this entry is already known, just update it */ + if (dat_entry) { + if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr)) + memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN); + dat_entry->last_update = jiffies; + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "Entry updated: %pI4 %pM\n", &dat_entry->ip, + dat_entry->mac_addr); + goto out; + } + + dat_entry = kmalloc(sizeof(*dat_entry), GFP_ATOMIC); + if (!dat_entry) + goto out; + + dat_entry->ip = ip; + memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN); + dat_entry->last_update = jiffies; + atomic_set(&dat_entry->refcount, 2); + + hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat, + batadv_hash_dat, &dat_entry->ip, + &dat_entry->hash_entry); + + if (unlikely(hash_added != 0)) { + /* remove the reference for the hash */ + batadv_dat_entry_free_ref(dat_entry); + goto out; + } + + batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM\n", + &dat_entry->ip, dat_entry->mac_addr); + +out: + if (dat_entry) + batadv_dat_entry_free_ref(dat_entry); +} + +/** * batadv_is_orig_node_eligible - check whether a node can be a DHT candidate * @res: the array with the already selected candidates * @select: number of already selected candidates @@ -268,3 +471,96 @@ out: kfree(cand); return ret; } + +/** + * batadv_dat_hash_free - free the local DAT hash table + * @bat_priv: the bat priv with all the soft interface information + */ +static void batadv_dat_hash_free(struct batadv_priv *bat_priv) +{ + __batadv_dat_purge(bat_priv, NULL); + + batadv_hash_destroy(bat_priv->dat.hash); + + bat_priv->dat.hash = NULL; +} + +/** + * batadv_dat_init - initialise the DAT internals + * @bat_priv: the bat priv with all the soft interface information + */ +int batadv_dat_init(struct batadv_priv *bat_priv) +{ + if (bat_priv->dat.hash) + return 0; + + bat_priv->dat.hash = batadv_hash_new(1024); + + if (!bat_priv->dat.hash) + return -ENOMEM; + + batadv_dat_start_timer(bat_priv); + + return 0; +} + +/** + * batadv_dat_free - free the DAT internals + * @bat_priv: the bat priv with all the soft interface information + */ +void batadv_dat_free(struct batadv_priv *bat_priv) +{ + cancel_delayed_work_sync(&bat_priv->dat.work); + + batadv_dat_hash_free(bat_priv); +} + +/** + * batadv_dat_cache_seq_print_text - print the local DAT hash table + * @seq: seq file to print on + * @offset: not used + */ +int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset) +{ + struct net_device *net_dev = (struct net_device *)seq->private; + struct batadv_priv *bat_priv = netdev_priv(net_dev); + struct batadv_hashtable *hash = bat_priv->dat.hash; + struct batadv_dat_entry *dat_entry; + struct batadv_hard_iface *primary_if; + struct hlist_node *node; + struct hlist_head *head; + unsigned long last_seen_jiffies; + int last_seen_msecs, last_seen_secs, last_seen_mins; + uint32_t i; + + primary_if = batadv_seq_print_text_primary_if_get(seq); + if (!primary_if) + goto out; + + seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name); + seq_printf(seq, " %-7s %-13s %5s\n", "IPv4", "MAC", + "last-seen"); + + for (i = 0; i < hash->size; i++) { + head = &hash->table[i]; + + rcu_read_lock(); + hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) { + last_seen_jiffies = jiffies - dat_entry->last_update; + last_seen_msecs = jiffies_to_msecs(last_seen_jiffies); + last_seen_mins = last_seen_msecs / 60000; + last_seen_msecs = last_seen_msecs % 60000; + last_seen_secs = last_seen_msecs / 1000; + + seq_printf(seq, " * %15pI4 %14pM %6i:%02i\n", + &dat_entry->ip, dat_entry->mac_addr, + last_seen_mins, last_seen_secs); + } + rcu_read_unlock(); + } + +out: + if (primary_if) + batadv_hardif_free_ref(primary_if); + return 0; +} diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h index ea9cbd8..1b88303 100644 --- a/net/batman-adv/distributed-arp-table.h +++ b/net/batman-adv/distributed-arp-table.h @@ -55,4 +55,8 @@ batadv_dat_init_own_addr(struct batadv_priv *bat_priv, bat_priv->dat.addr = (batadv_dat_addr_t)addr; }

+int batadv_dat_init(struct batadv_priv *bat_priv); +void batadv_dat_free(struct batadv_priv *bat_priv); +int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset); + #endif /* _NET_BATMAN_ADV_ARP_H_ */ diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c index afc07a8..dc33a0c 100644 --- a/net/batman-adv/main.c +++ b/net/batman-adv/main.c @@ -29,6 +29,7 @@ #include "hard-interface.h" #include "gateway_client.h" #include "bridge_loop_avoidance.h" +#include "distributed-arp-table.h" #include "vis.h" #include "hash.h" #include "bat_algo.h" @@ -128,6 +129,10 @@ int batadv_mesh_init(struct net_device *soft_iface) if (ret < 0) goto err;

+ ret = batadv_dat_init(bat_priv); + if (ret < 0) + goto err; + atomic_set(&bat_priv->gw.reselect, 0); atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);

@@ -155,6 +160,8 @@ void batadv_mesh_free(struct net_device *soft_iface)

batadv_bla_free(bat_priv);

+ batadv_dat_free(bat_priv); + free_percpu(bat_priv->bat_counters);

atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE); diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 5699f2b..25adfd2 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -44,6 +44,7 @@ #define BATADV_TT_LOCAL_TIMEOUT 3600000 /* in milliseconds */ #define BATADV_TT_CLIENT_ROAM_TIMEOUT 600000 /* in milliseconds */ #define BATADV_TT_CLIENT_TEMP_TIMEOUT 600000 /* in milliseconds */ +#define BATADV_DAT_ENTRY_TIMEOUT (5*60000) /* 5 mins in milliseconds */ /* sliding packet range of received originator messages in sequence numbers * (should be a multiple of our word size) */ diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index b57d93b..9ed1bb2 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -249,9 +249,13 @@ struct batadv_priv_vis { /** * struct batadv_priv_dat - per mesh interface DAT private data * @addr: node DAT address + * @hash: hashtable representing the local ARP cache + * @work: work queue callback item for cache purging */ struct batadv_priv_dat { batadv_dat_addr_t addr; + struct batadv_hashtable *hash; + struct delayed_work work; };

struct batadv_priv { @@ -465,6 +469,25 @@ struct batadv_algo_ops { };

/** + * struct batadv_dat_entry - it is a single entry of batman-adv ARP backend. It + * is used to stored ARP entries needed for the global DAT cache + * @ip: the IPv4 corresponding to this DAT/ARP entry + * @mac_addr: the MAC address associated to the stored IPv4 + * @last_update: time in jiffies when this entry was refreshed last time + * @hash_entry: hlist node for batadv_priv_dat::hash + * @refcount: number of contexts the object is used + * @rcu: struct used for freeing in an RCU-safe manner + */ +struct batadv_dat_entry { + __be32 ip; + uint8_t mac_addr[ETH_ALEN]; + unsigned long last_update; + struct hlist_node hash_entry; + atomic_t refcount; + struct rcu_head rcu; +}; + +/** * struct batadv_dat_candidate - candidate destination for DAT operations * @type: the type of the selected candidate. It can one of the following: * - BATADV_DAT_CANDIDATE_NOT_FOUND

In case of an ARP message going in or out the soft_iface, it is intercepted and a special action is performed. In particular the DHT helper functions previously implemented are used to store all the ARP entries belonging to the network in order to provide a fast and unicast lookup instead of the classic broadcast flooding mechanism. Each node stores the entries it is responsible for (following the DHT rules) in its soft_iface ARP table. This makes it possible to reuse the kernel data structures and functions for ARP management.

Signed-off-by: Antonio Quartulli ordex@autistici.org --- net/batman-adv/distributed-arp-table.c | 265 +++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 11 ++ net/batman-adv/main.h | 2 + net/batman-adv/routing.c | 29 +++- net/batman-adv/send.c | 4 + net/batman-adv/soft-interface.c | 16 +- 6 files changed, 325 insertions(+), 2 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 49a213c..f43bf8e 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -19,6 +19,7 @@

#include <linux/if_ether.h> #include <linux/if_arp.h> +#include <net/arp.h>

#include "main.h" #include "hash.h" @@ -27,6 +28,7 @@ #include "originator.h" #include "send.h" #include "types.h" +#include "translation-table.h" #include "unicast.h"

static void batadv_dat_purge(struct work_struct *work); @@ -766,3 +768,266 @@ static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv, out: return type; } + +/** + * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to + * answer using DAT + * @bat_priv: the bat priv with all the soft interface information + * @skb: packet to check + * + * Returns true if the message has been sent to the dht candidates, false + * otherwise. In case of true the message has to be enqueued to permit the + * fallback + */ +bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, + struct sk_buff *skb) +{ + uint16_t type = 0; + __be32 ip_dst, ip_src; + uint8_t *hw_src; + bool ret = false; + struct batadv_dat_entry *dat_entry = NULL; + struct sk_buff *skb_new; + struct batadv_hard_iface *primary_if = NULL; + + type = batadv_arp_get_type(bat_priv, skb, 0); + /* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast + * message to the selected DHT candidates + */ + if (type != ARPOP_REQUEST) + goto out; + + batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REQUEST"); + + ip_src = batadv_arp_ip_src(skb, 0); + hw_src = batadv_arp_hw_src(skb, 0); + ip_dst = batadv_arp_ip_dst(skb, 0); + + batadv_dat_entry_add(bat_priv, ip_src, hw_src); + + dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); + if (dat_entry) { + primary_if = batadv_primary_if_get_selected(bat_priv); + if (!primary_if) + goto out; + + skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src, + primary_if->soft_iface, ip_dst, hw_src, + dat_entry->mac_addr, hw_src); + if (!skb_new) + goto out; + + skb_reset_mac_header(skb_new); + skb_new->protocol = eth_type_trans(skb_new, + primary_if->soft_iface); + bat_priv->stats.rx_packets++; + bat_priv->stats.rx_bytes += skb->len + ETH_HLEN; + primary_if->soft_iface->last_rx = jiffies; + + netif_rx(skb_new); + batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n"); + ret = true; + } else { + /* Send the request on the DHT */ + ret = batadv_dat_send_data(bat_priv, skb, ip_dst, + BATADV_P_DAT_DHT_GET); + } +out: + if (dat_entry) + batadv_dat_entry_free_ref(dat_entry); + if (primary_if) + batadv_hardif_free_ref(primary_if); + return ret; +} + +/** + * batadv_dat_snoop_incoming_arp_request - snoop the ARP request and try to + * answer using the local DAT storage + * @bat_priv: the bat priv with all the soft interface information + * @skb: packet to check + * @hdr_size: size of the encapsulation header + * + * Returns true if the request has been answered, false otherwise + */ +bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, + struct sk_buff *skb, int hdr_size) +{ + uint16_t type; + __be32 ip_src, ip_dst; + uint8_t *hw_src; + struct sk_buff *skb_new; + struct batadv_hard_iface *primary_if = NULL; + struct batadv_dat_entry *dat_entry = NULL; + bool ret = false; + int err; + + type = batadv_arp_get_type(bat_priv, skb, hdr_size); + if (type != ARPOP_REQUEST) + goto out; + + hw_src = batadv_arp_hw_src(skb, hdr_size); + ip_src = batadv_arp_ip_src(skb, hdr_size); + ip_dst = batadv_arp_ip_dst(skb, hdr_size); + + batadv_dbg_arp(bat_priv, skb, type, hdr_size, + "Parsing incoming ARP REQUEST"); + + batadv_dat_entry_add(bat_priv, ip_src, hw_src); + + dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); + if (!dat_entry) + goto out; + + primary_if = batadv_primary_if_get_selected(bat_priv); + if (!primary_if) + goto out; + + skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src, + primary_if->soft_iface, ip_dst, hw_src, + dat_entry->mac_addr, hw_src); + + if (!skb_new) + goto out; + + /* to preserve backwards compatibility, here the node has to answer + * using the same packet type it received for the request. This is due + * to that if a node is not using the 4addr packet format it may not + * support it. + */ + if (hdr_size == sizeof(struct batadv_unicast_4addr_packet)) + err = batadv_unicast_4addr_send_skb(bat_priv, skb_new, + BATADV_P_DAT_CACHE_REPLY); + else + err = batadv_unicast_send_skb(bat_priv, skb_new); + + if (!err) + ret = true; +out: + if (dat_entry) + batadv_dat_entry_free_ref(dat_entry); + if (primary_if) + batadv_hardif_free_ref(primary_if); + if (ret) + kfree_skb(skb); + return ret; +} + +/** + * batadv_dat_snoop_outgoing_arp_reply - snoop the ARP reply and fill the DHT + * @bat_priv: the bat priv with all the soft interface information + * @skb: packet to check + */ +void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv, + struct sk_buff *skb) +{ + uint16_t type; + __be32 ip_src, ip_dst; + uint8_t *hw_src, *hw_dst; + + type = batadv_arp_get_type(bat_priv, skb, 0); + if (type != ARPOP_REPLY) + return; + + batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REPLY"); + + hw_src = batadv_arp_hw_src(skb, 0); + ip_src = batadv_arp_ip_src(skb, 0); + hw_dst = batadv_arp_hw_dst(skb, 0); + ip_dst = batadv_arp_ip_dst(skb, 0); + + batadv_dat_entry_add(bat_priv, ip_src, hw_src); + batadv_dat_entry_add(bat_priv, ip_dst, hw_dst); + + /* Send the ARP reply to the candidates for both the IP addresses that + * the node got within the ARP reply + */ + batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT); + batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT); +} +/** + * batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local + * DAT storage only + * @bat_priv: the bat priv with all the soft interface information + * @skb: packet to check + * @hdr_size: siaze of the encapsulation header + */ +bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, + struct sk_buff *skb, int hdr_size) +{ + uint16_t type; + __be32 ip_src, ip_dst; + uint8_t *hw_src, *hw_dst; + bool ret = false; + + type = batadv_arp_get_type(bat_priv, skb, hdr_size); + if (type != ARPOP_REPLY) + goto out; + + batadv_dbg_arp(bat_priv, skb, type, hdr_size, + "Parsing incoming ARP REPLY"); + + hw_src = batadv_arp_hw_src(skb, hdr_size); + ip_src = batadv_arp_ip_src(skb, hdr_size); + hw_dst = batadv_arp_hw_dst(skb, hdr_size); + ip_dst = batadv_arp_ip_dst(skb, hdr_size); + + /* Update our internal cache with both the IP addresses the node got + * within the ARP reply + */ + batadv_dat_entry_add(bat_priv, ip_src, hw_src); + batadv_dat_entry_add(bat_priv, ip_dst, hw_dst); + + /* if this REPLY is directed to a client of mine, let's deliver the + * packet to the interface + */ + ret = !batadv_is_my_client(bat_priv, hw_dst); +out: + /* if ret == false -> packet has to be delivered to the interface */ + return ret; +} + +/** + * batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped + * (because the node has already got the reply via DAT) or not + * @bat_priv: the bat priv with all the soft interface information + * @forw_packet: the broadcast packet + * + * Returns true if the node can drop the packet, false otherwise + */ +bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv, + struct batadv_forw_packet *forw_packet) +{ + uint16_t type; + __be32 ip_dst; + struct batadv_dat_entry *dat_entry = NULL; + bool ret = false; + const size_t bcast_len = sizeof(struct batadv_bcast_packet); + + /* If this packet is an ARP_REQUEST and the node already has the + * information that it is going to ask, then the packet can be dropped + */ + if (forw_packet->num_packets) + goto out; + + type = batadv_arp_get_type(bat_priv, forw_packet->skb, bcast_len); + if (type != ARPOP_REQUEST) + goto out; + + ip_dst = batadv_arp_ip_dst(forw_packet->skb, bcast_len); + dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst); + /* check if the node already got this entry */ + if (!dat_entry) { + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "ARP Request for %pI4: fallback\n", &ip_dst); + goto out; + } + + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "ARP Request for %pI4: fallback prevented\n", &ip_dst); + ret = true; + +out: + if (dat_entry) + batadv_dat_entry_free_ref(dat_entry); + return ret; +} diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h index f4e282a..01308ce 100644 --- a/net/batman-adv/distributed-arp-table.h +++ b/net/batman-adv/distributed-arp-table.h @@ -27,6 +27,17 @@

#define BATADV_DAT_ADDR_MAX ((batadv_dat_addr_t)~(batadv_dat_addr_t)0)

+bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, + struct sk_buff *skb); +bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, + struct sk_buff *skb, int hdr_size); +void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv, + struct sk_buff *skb); +bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, + struct sk_buff *skb, int hdr_size); +bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv, + struct batadv_forw_packet *forw_packet); + /** * batadv_dat_init_orig_node_addr - assign a DAT address to the orig_node * @orig_node: the node to assign the DAT address to diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 25adfd2..240c74f 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -74,6 +74,8 @@

#define BATADV_LOG_BUF_LEN 8192 /* has to be a power of 2 */

+/* msecs after which an ARP_REQUEST is sent in broadcast as fallback */ +#define ARP_REQ_DELAY 250 /* numbers of originator to contact for any PUT/GET DHT operation */ #define BATADV_DAT_CANDIDATES_NUM 3

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 859679b..1826699 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -28,6 +28,7 @@ #include "vis.h" #include "unicast.h" #include "bridge_loop_avoidance.h" +#include "distributed-arp-table.h"

static int batadv_route_unicast_packet(struct sk_buff *skb, struct batadv_hard_iface *recv_if); @@ -985,11 +986,13 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); struct batadv_unicast_packet *unicast_packet; int hdr_size = sizeof(*unicast_packet); + bool is4addr;

unicast_packet = (struct batadv_unicast_packet *)skb->data;

+ is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR; /* the caller function should have already pulled 2 bytes */ - if (unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR) + if (is4addr) hdr_size = sizeof(struct batadv_unicast_4addr_packet);

if (batadv_check_unicast_packet(skb, hdr_size) < 0) @@ -1000,9 +1003,17 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,

/* packet for me */ if (batadv_is_my_mac(unicast_packet->dest)) { + if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, + hdr_size)) + goto rx_success; + if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, + hdr_size)) + goto rx_success; + batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, NULL);

+rx_success: return NET_RX_SUCCESS; }

@@ -1038,8 +1049,17 @@ int batadv_recv_ucast_frag_packet(struct sk_buff *skb, if (!new_skb) return NET_RX_SUCCESS;

+ if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb, + hdr_size)) + goto rx_success; + if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb, + hdr_size)) + goto rx_success; + batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if, sizeof(struct batadv_unicast_packet), NULL); + +rx_success: return NET_RX_SUCCESS; }

@@ -1131,9 +1151,16 @@ int batadv_recv_bcast_packet(struct sk_buff *skb, if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size)) goto out;

+ if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size)) + goto rx_success; + if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size)) + goto rx_success; + /* broadcast for me */ batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size, orig_node); + +rx_success: ret = NET_RX_SUCCESS; goto out;

diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c index 570a8bc..660d9bf 100644 --- a/net/batman-adv/send.c +++ b/net/batman-adv/send.c @@ -18,6 +18,7 @@ */

#include "main.h" +#include "distributed-arp-table.h" #include "send.h" #include "routing.h" #include "translation-table.h" @@ -209,6 +210,9 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work) if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) goto out;

+ if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) + goto out; + /* rebroadcast packet */ rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 2f123a1..9dc0ae1 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -20,6 +20,7 @@ #include "main.h" #include "soft-interface.h" #include "hard-interface.h" +#include "distributed-arp-table.h" #include "routing.h" #include "send.h" #include "debugfs.h" @@ -155,6 +156,7 @@ static int batadv_interface_tx(struct sk_buff *skb, short vid __maybe_unused = -1; bool do_bcast = false; uint32_t seqno; + unsigned long brd_delay = 1;

if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) goto dropped; @@ -224,6 +226,13 @@ static int batadv_interface_tx(struct sk_buff *skb, if (!primary_if) goto dropped;

+ /* in case of ARP request, we do not immediately broadcasti the + * packet, instead we first wait for DAT to try to retrieve the + * correct ARP entry + */ + if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb)) + brd_delay = msecs_to_jiffies(ARP_REQ_DELAY); + if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0) goto dropped;

@@ -245,7 +254,7 @@ static int batadv_interface_tx(struct sk_buff *skb, seqno = atomic_inc_return(&bat_priv->bcast_seqno); bcast_packet->seqno = htonl(seqno);

- batadv_add_bcast_packet_to_list(bat_priv, skb, 1); + batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay);

/* a copy is stored in the bcast list, therefore removing * the original skb. @@ -260,6 +269,11 @@ static int batadv_interface_tx(struct sk_buff *skb, goto dropped; }

+ if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb)) + goto dropped; + + batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb); + ret = batadv_unicast_send_skb(bat_priv, skb); if (ret != 0) goto dropped_freed;

This patch adds a runtime switch that enables the user to turn the DAT feature on or off at runtime

Signed-off-by: Antonio Quartulli ordex@autistici.org --- net/batman-adv/distributed-arp-table.c | 18 ++++++++++++++++++ net/batman-adv/soft-interface.c | 3 +++ net/batman-adv/sysfs.c | 7 +++++++ net/batman-adv/types.h | 3 +++ 4 files changed, 31 insertions(+)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index f43bf8e..c1a74a1 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -621,6 +621,9 @@ out: */ static void batadv_dat_hash_free(struct batadv_priv *bat_priv) { + if (!bat_priv->dat.hash) + return; + __batadv_dat_purge(bat_priv, NULL);

batadv_hash_destroy(bat_priv->dat.hash); @@ -790,6 +793,9 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, struct sk_buff *skb_new; struct batadv_hard_iface *primary_if = NULL;

+ if (!atomic_read(&bat_priv->distributed_arp_table)) + goto out; + type = batadv_arp_get_type(bat_priv, skb, 0); /* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast * message to the selected DHT candidates @@ -861,6 +867,9 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv, bool ret = false; int err;

+ if (!atomic_read(&bat_priv->distributed_arp_table)) + goto out; + type = batadv_arp_get_type(bat_priv, skb, hdr_size); if (type != ARPOP_REQUEST) goto out; @@ -924,6 +933,9 @@ void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv, __be32 ip_src, ip_dst; uint8_t *hw_src, *hw_dst;

+ if (!atomic_read(&bat_priv->distributed_arp_table)) + return; + type = batadv_arp_get_type(bat_priv, skb, 0); if (type != ARPOP_REPLY) return; @@ -959,6 +971,9 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, uint8_t *hw_src, *hw_dst; bool ret = false;

+ if (!atomic_read(&bat_priv->distributed_arp_table)) + goto out; + type = batadv_arp_get_type(bat_priv, skb, hdr_size); if (type != ARPOP_REPLY) goto out; @@ -1003,6 +1018,9 @@ bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv, bool ret = false; const size_t bcast_len = sizeof(struct batadv_bcast_packet);

+ if (!atomic_read(&bat_priv->distributed_arp_table)) + goto out; + /* If this packet is an ARP_REQUEST and the node already has the * information that it is going to ask, then the packet can be dropped */ diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 9dc0ae1..7b4a3a3 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -480,6 +480,9 @@ struct net_device *batadv_softif_create(const char *name) atomic_set(&bat_priv->aggregated_ogms, 1); atomic_set(&bat_priv->bonding, 0); atomic_set(&bat_priv->bridge_loop_avoidance, 0); +#ifdef CONFIG_BATMAN_ADV_DAT + atomic_set(&bat_priv->distributed_arp_table, 1); +#endif atomic_set(&bat_priv->ap_isolation, 0); atomic_set(&bat_priv->vis_mode, BATADV_VIS_TYPE_CLIENT_UPDATE); atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF); diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c index 42cd09e..fa3cc1a 100644 --- a/net/batman-adv/sysfs.c +++ b/net/batman-adv/sysfs.c @@ -20,6 +20,7 @@ #include "main.h" #include "sysfs.h" #include "translation-table.h" +#include "distributed-arp-table.h" #include "originator.h" #include "hard-interface.h" #include "gateway_common.h" @@ -420,6 +421,9 @@ BATADV_ATTR_SIF_BOOL(bonding, S_IRUGO | S_IWUSR, NULL); #ifdef CONFIG_BATMAN_ADV_BLA BATADV_ATTR_SIF_BOOL(bridge_loop_avoidance, S_IRUGO | S_IWUSR, NULL); #endif +#ifdef CONFIG_BATMAN_ADV_DAT +BATADV_ATTR_SIF_BOOL(distributed_arp_table, S_IRUGO | S_IWUSR, NULL); +#endif BATADV_ATTR_SIF_BOOL(fragmentation, S_IRUGO | S_IWUSR, batadv_update_min_mtu); BATADV_ATTR_SIF_BOOL(ap_isolation, S_IRUGO | S_IWUSR, NULL); static BATADV_ATTR(vis_mode, S_IRUGO | S_IWUSR, batadv_show_vis_mode, @@ -445,6 +449,9 @@ static struct batadv_attribute *batadv_mesh_attrs[] = { #ifdef CONFIG_BATMAN_ADV_BLA &batadv_attr_bridge_loop_avoidance, #endif +#ifdef CONFIG_BATMAN_ADV_DAT + &batadv_attr_distributed_arp_table, +#endif &batadv_attr_fragmentation, &batadv_attr_ap_isolation, &batadv_attr_vis_mode, diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 00d3093..0afeb2b 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -275,6 +275,9 @@ struct batadv_priv { atomic_t fragmentation; /* boolean */ atomic_t ap_isolation; /* boolean */ atomic_t bridge_loop_avoidance; /* boolean */ +#ifdef CONFIG_BATMAN_ADV_DAT + atomic_t distributed_arp_table; /* boolean */ +#endif atomic_t vis_mode; /* VIS_TYPE_* */ atomic_t gw_mode; /* GW_MODE_* */ atomic_t gw_sel_class; /* uint */