xref: /linux/net/batman-adv/gateway_common.c (revision 91ec2035134982b98fab0609a9fd8480e8217dc1)
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/byteorder/generic.h>
11 #include <linux/compiler.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 mesh interface information
24  */
batadv_gw_tvlv_container_update(struct batadv_priv * bat_priv)25 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
26 {
27 	struct batadv_tvlv_gateway_data gw;
28 	enum batadv_gw_modes gw_mode;
29 	u32 down;
30 	u32 up;
31 
32 	gw_mode = READ_ONCE(bat_priv->gw.mode);
33 
34 	switch (gw_mode) {
35 	case BATADV_GW_MODE_OFF:
36 	case BATADV_GW_MODE_CLIENT:
37 		batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
38 		break;
39 	case BATADV_GW_MODE_SERVER:
40 		down = READ_ONCE(bat_priv->gw.bandwidth_down);
41 		up = READ_ONCE(bat_priv->gw.bandwidth_up);
42 		gw.bandwidth_down = htonl(down);
43 		gw.bandwidth_up = htonl(up);
44 		batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
45 					       &gw, sizeof(gw));
46 		break;
47 	}
48 }
49 
50 /**
51  * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container
52  * @bat_priv: the bat priv with all the mesh interface information
53  * @orig: the orig_node of the ogm
54  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
55  * @tvlv_value: tvlv buffer containing the gateway data
56  * @tvlv_value_len: tvlv buffer length
57  */
batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv * bat_priv,struct batadv_orig_node * orig,u8 flags,void * tvlv_value,u16 tvlv_value_len)58 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
59 					  struct batadv_orig_node *orig,
60 					  u8 flags,
61 					  void *tvlv_value, u16 tvlv_value_len)
62 {
63 	struct batadv_tvlv_gateway_data *gateway_ptr;
64 	struct batadv_tvlv_gateway_data gateway;
65 
66 	/* only fetch the tvlv value if the handler wasn't called via the
67 	 * CIFNOTFND flag and if there is data to fetch
68 	 */
69 	if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND ||
70 	    tvlv_value_len < sizeof(gateway)) {
71 		gateway.bandwidth_down = 0;
72 		gateway.bandwidth_up = 0;
73 	} else {
74 		gateway_ptr = tvlv_value;
75 		gateway.bandwidth_down = gateway_ptr->bandwidth_down;
76 		gateway.bandwidth_up = gateway_ptr->bandwidth_up;
77 		if (gateway.bandwidth_down == 0 ||
78 		    gateway.bandwidth_up == 0) {
79 			gateway.bandwidth_down = 0;
80 			gateway.bandwidth_up = 0;
81 		}
82 	}
83 
84 	batadv_gw_node_update(bat_priv, orig, &gateway);
85 
86 	/* restart gateway selection */
87 	if (gateway.bandwidth_down != 0 &&
88 	    READ_ONCE(bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT)
89 		batadv_gw_check_election(bat_priv, orig);
90 }
91 
92 /**
93  * batadv_gw_init() - initialise the gateway handling internals
94  * @bat_priv: the bat priv with all the mesh interface information
95  */
batadv_gw_init(struct batadv_priv * bat_priv)96 void batadv_gw_init(struct batadv_priv *bat_priv)
97 {
98 	if (bat_priv->algo_ops->gw.init_sel_class)
99 		bat_priv->algo_ops->gw.init_sel_class(bat_priv);
100 	else
101 		WRITE_ONCE(bat_priv->gw.sel_class, 1);
102 
103 	batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
104 				     NULL, NULL, BATADV_TVLV_GW, 1,
105 				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
106 }
107 
108 /**
109  * batadv_gw_free() - free the gateway handling internals
110  * @bat_priv: the bat priv with all the mesh interface information
111  */
batadv_gw_free(struct batadv_priv * bat_priv)112 void batadv_gw_free(struct batadv_priv *bat_priv)
113 {
114 	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
115 	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
116 }
117