net/batman-adv/gateway_common.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) B.A.T.M.A.N. contributors:
   3  *
   4  * Marek Lindner
   5  */
   6
   7 #include "gateway_common.h"
   8 #include "main.h"
   9
  10 #include <linux/atomic.h>
  11 #include <linux/byteorder/generic.h>
  12 #include <linux/stddef.h>
  13 #include <linux/types.h>
  14 #include <uapi/linux/batadv_packet.h>
  15 #include <uapi/linux/batman_adv.h>
  16
  17 #include "gateway_client.h"
  18 #include "tvlv.h"
  19
  20 /**
  21  * batadv_gw_tvlv_container_update() - update the gw tvlv container after
  22  *  gateway setting change
  23  * @bat_priv: the bat priv with all the soft interface information
  24  */
  25 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
  26 {
  27         struct batadv_tvlv_gateway_data gw;
  28         u32 down, up;
  29         char gw_mode;
  30
  31         gw_mode = atomic_read(&bat_priv->gw.mode);
  32
  33         switch (gw_mode) {
  34         case BATADV_GW_MODE_OFF:
  35         case BATADV_GW_MODE_CLIENT:
  36                 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
  37                 break;
  38         case BATADV_GW_MODE_SERVER:
  39                 down = atomic_read(&bat_priv->gw.bandwidth_down);
  40                 up = atomic_read(&bat_priv->gw.bandwidth_up);
  41                 gw.bandwidth_down = htonl(down);
  42                 gw.bandwidth_up = htonl(up);
  43                 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
  44                                                &gw, sizeof(gw));
  45                 break;
  46         }
  47 }
  48
  49 /**
  50  * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container
  51  * @bat_priv: the bat priv with all the soft interface information
  52  * @orig: the orig_node of the ogm
  53  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
  54  * @tvlv_value: tvlv buffer containing the gateway data
  55  * @tvlv_value_len: tvlv buffer length
  56  */
  57 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
  58                                           struct batadv_orig_node *orig,
  59                                           u8 flags,
  60                                           void *tvlv_value, u16 tvlv_value_len)
  61 {
  62         struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
  63
  64         /* only fetch the tvlv value if the handler wasn't called via the
  65          * CIFNOTFND flag and if there is data to fetch
  66          */
  67         if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND ||
  68             tvlv_value_len < sizeof(gateway)) {
  69                 gateway.bandwidth_down = 0;
  70                 gateway.bandwidth_up = 0;
  71         } else {
  72                 gateway_ptr = tvlv_value;
  73                 gateway.bandwidth_down = gateway_ptr->bandwidth_down;
  74                 gateway.bandwidth_up = gateway_ptr->bandwidth_up;
  75                 if (gateway.bandwidth_down == 0 ||
  76                     gateway.bandwidth_up == 0) {
  77                         gateway.bandwidth_down = 0;
  78                         gateway.bandwidth_up = 0;
  79                 }
  80         }
  81
  82         batadv_gw_node_update(bat_priv, orig, &gateway);
  83
  84         /* restart gateway selection */
  85         if (gateway.bandwidth_down != 0 &&
  86             atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT)
  87                 batadv_gw_check_election(bat_priv, orig);
  88 }
  89
  90 /**
  91  * batadv_gw_init() - initialise the gateway handling internals
  92  * @bat_priv: the bat priv with all the soft interface information
  93  */
  94 void batadv_gw_init(struct batadv_priv *bat_priv)
  95 {
  96         if (bat_priv->algo_ops->gw.init_sel_class)
  97                 bat_priv->algo_ops->gw.init_sel_class(bat_priv);
  98         else
  99                 atomic_set(&bat_priv->gw.sel_class, 1);
 100
 101         batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
 102                                      NULL, NULL, BATADV_TVLV_GW, 1,
 103                                      BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
 104 }
 105
 106 /**
 107  * batadv_gw_free() - free the gateway handling internals
 108  * @bat_priv: the bat priv with all the soft interface information
 109  */
 110 void batadv_gw_free(struct batadv_priv *bat_priv)
 111 {
 112         batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
 113         batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
 114 }