From: Linus Lüssing linus.luessing@ascom.ch
This reduces the size of recv_bcast_packet, increasing its readability. It further introduces a generic function for duplicate checking for data packets (which might later be used for multicast or promiscous unicast packet handling or other packets).
Signed-off-by: Linus Lüssing linus.luessing@ascom.ch --- originator.c | 2 +- routing.c | 86 +++++++++++++++++++++++++++++++++++---------------------- types.h | 10 +++++-- 3 files changed, 61 insertions(+), 37 deletions(-)
diff --git a/originator.c b/originator.c index 8930446..e888416 100644 --- a/originator.c +++ b/originator.c @@ -147,7 +147,7 @@ struct orig_node *get_orig_node(struct bat_priv *bat_priv, uint8_t *addr) memcpy(orig_node->orig, addr, ETH_ALEN); orig_node->router = NULL; orig_node->hna_buff = NULL; - orig_node->bcast_seqno_reset = jiffies - 1 + orig_node->bcast_seqno_state.seqno_reset = jiffies - 1 - msecs_to_jiffies(RESET_PROTECTION_MS); orig_node->batman_seqno_reset = jiffies - 1 - msecs_to_jiffies(RESET_PROTECTION_MS); diff --git a/routing.c b/routing.c index b61821a..761fd84 100644 --- a/routing.c +++ b/routing.c @@ -1129,6 +1129,55 @@ static int check_unicast_packet(struct sk_buff *skb, int hdr_size) return 0; }
+static inline int check_duplicate(struct bat_priv *bat_priv, uint8_t *orig, + uint32_t seqno, uint8_t packet_type) +{ + struct orig_node *orig_node; + struct seqno_state *seqno_state; + int32_t seq_diff; + int ret = 1; + + spin_lock_bh(&bat_priv->orig_hash_lock); + orig_node = ((struct orig_node *) + hash_find(bat_priv->orig_hash, compare_orig, choose_orig, + orig)); + + switch (packet_type) { + case BAT_BCAST: + seqno_state = &orig_node->bcast_seqno_state; + break; + default: + goto out; + } + + if (orig_node == NULL) + goto out; + + /* check whether the packet is a duplicate */ + if (get_bit_status(seqno_state->bits, + seqno_state->last_seqno, + seqno)) + goto out; + + seq_diff = seqno - seqno_state->last_seqno; + + /* check whether the packet is old and the host just restarted. */ + if (window_protected(bat_priv, seq_diff, + &seqno_state->seqno_reset)) + goto out; + + /* mark broadcast in flood history, update window position + * if required. */ + if (bit_get_packet(bat_priv, seqno_state->bits, seq_diff, 1)) + seqno_state->last_seqno = seqno; + + ret = 0; + +out: + spin_unlock_bh(&bat_priv->orig_hash_lock); + return ret; +} + int route_unicast_packet(struct sk_buff *skb, struct batman_if *recv_if, int hdr_size) { @@ -1275,11 +1324,10 @@ int recv_ucast_frag_packet(struct sk_buff *skb, struct batman_if *recv_if) int recv_bcast_packet(struct sk_buff *skb, struct batman_if *recv_if) { struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface); - struct orig_node *orig_node; struct bcast_packet *bcast_packet; struct ethhdr *ethhdr; int hdr_size = sizeof(struct bcast_packet); - int32_t seq_diff; + int ret;
/* drop packet if it has not necessary minimum size */ if (unlikely(!pskb_may_pull(skb, hdr_size))) @@ -1308,39 +1356,11 @@ int recv_bcast_packet(struct sk_buff *skb, struct batman_if *recv_if) if (bcast_packet->ttl < 2) return NET_RX_DROP;
- spin_lock_bh(&bat_priv->orig_hash_lock); - orig_node = ((struct orig_node *) - hash_find(bat_priv->orig_hash, compare_orig, choose_orig, - bcast_packet->orig)); - - if (orig_node == NULL) { - spin_unlock_bh(&bat_priv->orig_hash_lock); + ret = check_duplicate(bat_priv, bcast_packet->orig, + ntohl(bcast_packet->seqno), BAT_BCAST); + if (ret) return NET_RX_DROP; - }
- /* check whether the packet is a duplicate */ - if (get_bit_status(orig_node->bcast_bits, - orig_node->last_bcast_seqno, - ntohl(bcast_packet->seqno))) { - spin_unlock_bh(&bat_priv->orig_hash_lock); - return NET_RX_DROP; - } - - seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno; - - /* check whether the packet is old and the host just restarted. */ - if (window_protected(bat_priv, seq_diff, - &orig_node->bcast_seqno_reset)) { - spin_unlock_bh(&bat_priv->orig_hash_lock); - return NET_RX_DROP; - } - - /* mark broadcast in flood history, update window position - * if required. */ - if (bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1)) - orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno); - - spin_unlock_bh(&bat_priv->orig_hash_lock); /* rebroadcast packet */ add_bcast_packet_to_list(bat_priv, skb);
diff --git a/types.h b/types.h index 2678ce1..87eb780 100644 --- a/types.h +++ b/types.h @@ -49,6 +49,12 @@ struct batman_if { struct rcu_head rcu; };
+struct seqno_state { + unsigned long seqno_reset; + uint32_t last_seqno; + TYPE_OF_WORD bits[NUM_WORDS]; +}; + /** * orig_node - structure for orig_list maintaining nodes of mesh * @primary_addr: hosts primary interface address @@ -73,7 +79,6 @@ struct orig_node { uint8_t tq_own; int tq_asym_penalty; unsigned long last_valid; - unsigned long bcast_seqno_reset; unsigned long batman_seqno_reset; uint8_t gw_flags; uint8_t flags; @@ -81,11 +86,10 @@ struct orig_node { int16_t hna_buff_len; uint32_t last_real_seqno; uint8_t last_ttl; - TYPE_OF_WORD bcast_bits[NUM_WORDS]; - uint32_t last_bcast_seqno; struct list_head neigh_list; struct list_head frag_list; unsigned long last_frag_packet; + struct seqno_state bcast_seqno_state; struct { uint8_t candidates; struct neigh_node *selected;