The following commit has been merged in the master branch: commit 1887248c268928ebb434edab611978f51e2a4b8f Author: Marek Lindner lindner_marek@yahoo.de Date: Thu Mar 1 15:35:17 2012 +0800
batman-adv: introduce packet type handler array for incoming packets
The packet handler array replaces the growing switch statement, thus dealing with incoming packets in a more efficient way. It also adds to possibility to register packet handlers on the fly.
Signed-off-by: Marek Lindner lindner_marek@yahoo.de Acked-by: Simon Wunderlich siwu@hrz.tu-chemnitz.de
diff --git a/hard-interface.c b/hard-interface.c index cf43540..3ddd5de 100644 --- a/hard-interface.c +++ b/hard-interface.c @@ -33,12 +33,6 @@
#include <linux/if_arp.h>
- -static int batman_skb_recv(struct sk_buff *skb, - struct net_device *dev, - struct packet_type *ptype, - struct net_device *orig_dev); - void hardif_free_rcu(struct rcu_head *rcu) { struct hard_iface *hard_iface; @@ -567,114 +561,6 @@ out: return NOTIFY_DONE; }
-/* incoming packets with the batman ethertype received on any active hard - * interface */ -static int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, - struct packet_type *ptype, - struct net_device *orig_dev) -{ - struct bat_priv *bat_priv; - struct batman_ogm_packet *batman_ogm_packet; - struct hard_iface *hard_iface; - int ret; - - hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype); - skb = skb_share_check(skb, GFP_ATOMIC); - - /* skb was released by skb_share_check() */ - if (!skb) - goto err_out; - - /* packet should hold at least type and version */ - if (unlikely(!pskb_may_pull(skb, 2))) - goto err_free; - - /* expect a valid ethernet header here. */ - if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb))) - goto err_free; - - if (!hard_iface->soft_iface) - goto err_free; - - bat_priv = netdev_priv(hard_iface->soft_iface); - - if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) - goto err_free; - - /* discard frames on not active interfaces */ - if (hard_iface->if_status != IF_ACTIVE) - goto err_free; - - batman_ogm_packet = (struct batman_ogm_packet *)skb->data; - - if (batman_ogm_packet->header.version != COMPAT_VERSION) { - bat_dbg(DBG_BATMAN, bat_priv, - "Drop packet: incompatible batman version (%i)\n", - batman_ogm_packet->header.version); - goto err_free; - } - - /* all receive handlers return whether they received or reused - * the supplied skb. if not, we have to free the skb. */ - - switch (batman_ogm_packet->header.packet_type) { - /* batman originator packet */ - case BAT_IV_OGM: - ret = recv_bat_ogm_packet(skb, hard_iface); - break; - - /* batman icmp packet */ - case BAT_ICMP: - ret = recv_icmp_packet(skb, hard_iface); - break; - - /* unicast packet */ - case BAT_UNICAST: - case BAT_UNICAST_4ADDR: - ret = recv_unicast_packet(skb, hard_iface); - break; - - /* fragmented unicast packet */ - case BAT_UNICAST_FRAG: - ret = recv_ucast_frag_packet(skb, hard_iface); - break; - - /* broadcast packet */ - case BAT_BCAST: - ret = recv_bcast_packet(skb, hard_iface); - break; - - /* vis packet */ - case BAT_VIS: - ret = recv_vis_packet(skb, hard_iface); - break; - /* Translation table query (request or response) */ - case BAT_TT_QUERY: - ret = recv_tt_query(skb, hard_iface); - break; - /* Roaming advertisement */ - case BAT_ROAM_ADV: - ret = recv_roam_adv(skb, hard_iface); - break; - default: - ret = NET_RX_DROP; - } - - if (ret == NET_RX_DROP) - kfree_skb(skb); - - /* return NET_RX_SUCCESS in any case as we - * most probably dropped the packet for - * routing-logical reasons. */ - - return NET_RX_SUCCESS; - -err_free: - kfree_skb(skb); -err_out: - return NET_RX_DROP; -} - /* This function returns true if the interface represented by ifindex is a * 802.11 wireless device */ bool is_wifi_iface(int ifindex) diff --git a/main.c b/main.c index 87b75a9..0d0cd48 100644 --- a/main.c +++ b/main.c @@ -39,6 +39,7 @@ /* List manipulations on hardif_list have to be rtnl_lock()'ed, * list traversals just rcu-locked */ struct list_head hardif_list; +static int (*recv_packet_handler[256])(struct sk_buff *, struct hard_iface *); char bat_routing_algo[20] = "BATMAN IV"; static struct hlist_head bat_algo_list;
@@ -46,11 +47,15 @@ unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
struct workqueue_struct *bat_event_workqueue;
+static void recv_handler_init(void); + static int __init batman_init(void) { INIT_LIST_HEAD(&hardif_list); INIT_HLIST_HEAD(&bat_algo_list);
+ recv_handler_init(); + bat_iv_init();
/* the name should not be longer than 10 chars - see @@ -179,6 +184,119 @@ int is_my_mac(const uint8_t *addr) return 0; }
+static int recv_unhandled_packet(struct sk_buff *skb, + struct hard_iface *recv_if) +{ + return NET_RX_DROP; +} + +/* incoming packets with the batman ethertype received on any active hard + * interface */ +int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *ptype, struct net_device *orig_dev) +{ + struct bat_priv *bat_priv; + struct batman_ogm_packet *batman_ogm_packet; + struct hard_iface *hard_iface; + uint8_t idx; + int ret; + + hard_iface = container_of(ptype, struct hard_iface, batman_adv_ptype); + skb = skb_share_check(skb, GFP_ATOMIC); + + /* skb was released by skb_share_check() */ + if (!skb) + goto err_out; + + /* packet should hold at least type and version */ + if (unlikely(!pskb_may_pull(skb, 2))) + goto err_free; + + /* expect a valid ethernet header here. */ + if (unlikely(skb->mac_len != ETH_HLEN || !skb_mac_header(skb))) + goto err_free; + + if (!hard_iface->soft_iface) + goto err_free; + + bat_priv = netdev_priv(hard_iface->soft_iface); + + if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) + goto err_free; + + /* discard frames on not active interfaces */ + if (hard_iface->if_status != IF_ACTIVE) + goto err_free; + + batman_ogm_packet = (struct batman_ogm_packet *)skb->data; + + if (batman_ogm_packet->header.version != COMPAT_VERSION) { + bat_dbg(DBG_BATMAN, bat_priv, + "Drop packet: incompatible batman version (%i)\n", + batman_ogm_packet->header.version); + goto err_free; + } + + /* all receive handlers return whether they received or reused + * the supplied skb. if not, we have to free the skb. */ + idx = batman_ogm_packet->header.packet_type; + ret = (*recv_packet_handler[idx])(skb, hard_iface); + + if (ret == NET_RX_DROP) + kfree_skb(skb); + + /* return NET_RX_SUCCESS in any case as we + * most probably dropped the packet for + * routing-logical reasons. */ + return NET_RX_SUCCESS; + +err_free: + kfree_skb(skb); +err_out: + return NET_RX_DROP; +} + +static void recv_handler_init(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(recv_packet_handler); i++) + recv_packet_handler[i] = recv_unhandled_packet; + + /* batman originator packet */ + recv_packet_handler[BAT_IV_OGM] = recv_bat_ogm_packet; + /* batman icmp packet */ + recv_packet_handler[BAT_ICMP] = recv_icmp_packet; + /* unicast packet */ + recv_packet_handler[BAT_UNICAST] = recv_unicast_packet; + /* fragmented unicast packet */ + recv_packet_handler[BAT_UNICAST_FRAG] = recv_ucast_frag_packet; + /* broadcast packet */ + recv_packet_handler[BAT_BCAST] = recv_bcast_packet; + /* vis packet */ + recv_packet_handler[BAT_VIS] = recv_vis_packet; + /* Translation table query (request or response) */ + recv_packet_handler[BAT_TT_QUERY] = recv_tt_query; + /* Roaming advertisement */ + recv_packet_handler[BAT_ROAM_ADV] = recv_roam_adv; +} + +int recv_handler_register(uint8_t packet_type, + int (*recv_handler)(struct sk_buff *, + struct hard_iface *)) +{ + if (recv_packet_handler[packet_type] != &recv_unhandled_packet) + return -EBUSY; + + recv_packet_handler[packet_type] = recv_handler; + return 0; +} + +void recv_handler_unregister(uint8_t packet_type) +{ + recv_packet_handler[packet_type] = recv_unhandled_packet; +} + static struct bat_algo_ops *bat_algo_get(char *name) { struct bat_algo_ops *bat_algo_ops = NULL, *bat_algo_ops_tmp; diff --git a/main.h b/main.h index 218be63..c25ad17 100644 --- a/main.h +++ b/main.h @@ -178,6 +178,12 @@ void mesh_free(struct net_device *soft_iface); void inc_module_count(void); void dec_module_count(void); int is_my_mac(const uint8_t *addr); +int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *ptype, struct net_device *orig_dev); +int recv_handler_register(uint8_t packet_type, + int (*recv_handler)(struct sk_buff *, + struct hard_iface *)); +void recv_handler_unregister(uint8_t packet_type); int bat_algo_register(struct bat_algo_ops *bat_algo_ops); int bat_algo_select(struct bat_priv *bat_priv, char *name); int bat_algo_seq_print_text(struct seq_file *seq, void *offset);