[B.A.T.M.A.N.] [PATCH 14/16] batman-adv: reorder packet types

Antonio Quartulli
2013-10-09T19:32:52Z

From: Simon Wunderlich <simon.wunderlich@s2003.tu-chemnitz.de>

Reordering the packet type numbers allows us to handle unicast
packets in a general way - even if we don't know the specific packet
type, we can still forward it. There was already code handling
this for a couple of unicast packets, and this is the more
generalized version to do that.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
---
net/batman-adv/main.c | 20 +++++++++++++++-----
net/batman-adv/packet.h | 31 +++++++++++++++++++++++--------
net/batman-adv/routing.c | 28 ++++++++++++++++++++++++++++
net/batman-adv/routing.h | 2 ++
4 files changed, 68 insertions(+), 13 deletions(-)

diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index b22368e..8b195e6 100644
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -393,6 +393,9 @@ static void batadv_recv_handler_init(void)
for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
batadv_rx_handler[i] = batadv_recv_unhandled_packet;

+ for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++)
+ batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet;
+
/* compile time checks for struct member offsets */
BUILD_BUG_ON(offsetof(struct batadv_unicast_4addr_packet, src) != 10);
BUILD_BUG_ON(offsetof(struct batadv_unicast_packet, dest) != 4);
@@ -401,18 +404,20 @@ static void batadv_recv_handler_init(void)
BUILD_BUG_ON(offsetof(struct batadv_icmp_packet, dst) != 4);
BUILD_BUG_ON(offsetof(struct batadv_icmp_packet_rr, dst) != 4);

- /* batman icmp packet */
- batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
+ /* broadcast packet */
+ batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
+
+ /* unicast packets ... */
/* 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 */
batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
- /* broadcast packet */
- batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
/* unicast tvlv packet */
batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv;
+ /* batman icmp packet */
+ batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
}

int
@@ -420,7 +425,12 @@ batadv_recv_handler_register(uint8_t packet_type,
int (*recv_handler)(struct sk_buff *,
struct batadv_hard_iface *))
{
- if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
+ int (*curr)(struct sk_buff *,
+ struct batadv_hard_iface *);
+ curr = batadv_rx_handler[packet_type];
+
+ if ((curr != batadv_recv_unhandled_packet) &&
+ (curr != batadv_recv_unhandled_unicast_packet))
return -EBUSY;

batadv_rx_handler[packet_type] = recv_handler;
diff --git a/net/batman-adv/packet.h b/net/batman-adv/packet.h
index 87fcf2e..f02dbb1 100644
--- a/net/batman-adv/packet.h
+++ b/net/batman-adv/packet.h
@@ -22,17 +22,32 @@

/**
* enum batadv_packettype - types for batman-adv encapsulated packets
+ * @BATADV_IV_OGM: originator messages for B.A.T.M.A.N. IV
+ * @BATADV_BCAST: broadcast packets carrying broadcast payload
+ * @BATADV_CODED: network coded packets
+ *
+ * @BATADV_UNICAST: unicast packets carrying unicast payload traffic
+ * @BATADV_UNICAST_FRAG: unicast packets carrying a fragment of the original
+ * payload packet
+ * @BATADV_UNICAST_4ADDR: unicast packet including the originator address of
+ * the sender
+ * @BATADV_ICMP: unicast packet like IP ICMP used for ping or traceroute
* @BATADV_UNICAST_TVLV: unicast packet carrying TVLV containers
*/
enum batadv_packettype {
- BATADV_IV_OGM = 0x01,
- BATADV_ICMP = 0x02,
- BATADV_UNICAST = 0x03,
- BATADV_BCAST = 0x04,
- BATADV_UNICAST_FRAG = 0x06,
- BATADV_UNICAST_4ADDR = 0x09,
- BATADV_CODED = 0x0a,
- BATADV_UNICAST_TVLV = 0x0b,
+ /* 0x00 - 0x3f: local packets or special rules for handling */
+ BATADV_IV_OGM = 0x00,
+ BATADV_BCAST = 0x01,
+ BATADV_CODED = 0x02,
+ /* 0x40 - 0x7f: unicast */
+#define BATADV_UNICAST_MIN 0x40
+ BATADV_UNICAST = 0x40,
+ BATADV_UNICAST_FRAG = 0x41,
+ BATADV_UNICAST_4ADDR = 0x42,
+ BATADV_ICMP = 0x43,
+ BATADV_UNICAST_TVLV = 0x44,
+#define BATADV_UNICAST_MAX 0x7f
+ /* 0x80 - 0xff: reserved */
};

/**
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 2a9318b..457dfef 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -911,6 +911,34 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
return 1;
}

+/**
+ * batadv_recv_unhandled_unicast_packet - receive and process packets which
+ * are in the unicast number space but not yet known to the implementation
+ * @skb: unicast tvlv packet to process
+ * @recv_if: pointer to interface this packet was received on
+ *
+ * Returns NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
+ * otherwise.
+ */
+int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
+ struct batadv_hard_iface *recv_if)
+{
+ struct batadv_unicast_packet *unicast_packet;
+ struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
+ int check, hdr_size = sizeof(*unicast_packet);
+
+ check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
+ if (check < 0)
+ return NET_RX_DROP;
+
+ /* we don't know about this type, drop it. */
+ unicast_packet = (struct batadv_unicast_packet *)skb->data;
+ if (batadv_is_my_mac(bat_priv, unicast_packet->dest))
+ return NET_RX_DROP;
+
+ return batadv_route_unicast_packet(skb, recv_if);
+}
+
int batadv_recv_unicast_packet(struct sk_buff *skb,
struct batadv_hard_iface *recv_if)
{
diff --git a/net/batman-adv/routing.h b/net/batman-adv/routing.h
index b3f53d4..ea15fa6 100644
--- a/net/batman-adv/routing.h
+++ b/net/batman-adv/routing.h
@@ -40,6 +40,8 @@ int batadv_recv_roam_adv(struct sk_buff *skb,
struct batadv_hard_iface *recv_if);
int batadv_recv_unicast_tvlv(struct sk_buff *skb,
struct batadv_hard_iface *recv_if);
+int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
+ struct batadv_hard_iface *recv_if);
struct batadv_neigh_node *
batadv_find_router(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig_node,
--
1.8.3.2