batman-adv: tvlv - basic infrastructure

The goal is to provide the infrastructure for sending, receiving and
parsing information 'containers' while preserving backward
compatibility. TVLV (based on the commonly known Type Length Value
technique) was chosen as the format for those containers. Even if a
node does not know the tvlv type of a certain container it can simply
skip the current container and proceed with the next. Past experience
has shown features evolve over time, so a 'version' field was added
right from the start to allow differentiating between feature
variants - hence the name: T(ype) V(ersion) L(ength) V(alue).

This patch introduces the basic TVLV infrastructure:
 * register / unregister tvlv containers to be sent with each OGM
   (on primary interfaces only)
 * register / unregister callback handlers to be called upon
   finding the corresponding tvlv type in a tvlv buffer
 * unicast tvlv send / receive API calls

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Spyros Gasteratos <morfeas3000@gmail.com>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index 24675523930f..397722fb509b 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -326,4 +326,39 @@ static inline uint64_t batadv_sum_counter(struct batadv_priv *bat_priv,
  */
 #define BATADV_SKB_CB(__skb)       ((struct batadv_skb_cb *)&((__skb)->cb[0]))
 
+void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
+                                    uint8_t type, uint8_t version,
+                                    void *tvlv_value, uint16_t tvlv_value_len);
+uint16_t batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
+                                          unsigned char **packet_buff,
+                                          int *packet_buff_len,
+                                          int packet_min_len);
+void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
+                             struct batadv_ogm_packet *batadv_ogm_packet,
+                             struct batadv_orig_node *orig_node);
+void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
+                                      uint8_t type, uint8_t version);
+
+void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
+                                  void (*optr)(struct batadv_priv *bat_priv,
+                                               struct batadv_orig_node *orig,
+                                               uint8_t flags,
+                                               void *tvlv_value,
+                                               uint16_t tvlv_value_len),
+                                  int (*uptr)(struct batadv_priv *bat_priv,
+                                              uint8_t *src, uint8_t *dst,
+                                              void *tvlv_value,
+                                              uint16_t tvlv_value_len),
+                                  uint8_t type, uint8_t version, uint8_t flags);
+void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
+                                    uint8_t type, uint8_t version);
+int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
+                                   bool ogm_source,
+                                   struct batadv_orig_node *orig_node,
+                                   uint8_t *src, uint8_t *dst,
+                                   void *tvlv_buff, uint16_t tvlv_buff_len);
+void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, uint8_t *src,
+                              uint8_t *dst, uint8_t type, uint8_t version,
+                              void *tvlv_value, uint16_t tvlv_value_len);
+
 #endif /* _NET_BATMAN_ADV_MAIN_H_ */