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 */
25void 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 */
57static 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 */
94void 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 */
110void 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}
115