diff options
Diffstat (limited to 'net/batman-adv/unicast.c')
-rw-r--r-- | net/batman-adv/unicast.c | 143 |
1 files changed, 125 insertions, 18 deletions
diff --git a/net/batman-adv/unicast.c b/net/batman-adv/unicast.c index f397232..10aff49 100644 --- a/net/batman-adv/unicast.c +++ b/net/batman-adv/unicast.c @@ -291,14 +291,118 @@ 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 + */ +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; + unicast_4addr_packet->reserved = 0; + + 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; 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 */ @@ -324,21 +428,23 @@ 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 +454,9 @@ 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++; @@ -358,16 +466,15 @@ 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 = 0; 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; } |