1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
3  *
4  * Marek Lindner, Simon Wunderlich
5  */
6 
7 #ifndef _NET_BATMAN_ADV_MAIN_H_
8 #define _NET_BATMAN_ADV_MAIN_H_
9 
10 #define BATADV_DRIVER_AUTHOR "Marek Lindner <mareklindner@neomailbox.ch>, " \
11 			     "Simon Wunderlich <sw@simonwunderlich.de>"
12 #define BATADV_DRIVER_DESC   "B.A.T.M.A.N. advanced"
13 #define BATADV_DRIVER_DEVICE "batman-adv"
14 
15 #ifndef BATADV_SOURCE_VERSION
16 #define BATADV_SOURCE_VERSION "2019.4"
17 #endif
18 
19 /* B.A.T.M.A.N. parameters */
20 
21 #define BATADV_TQ_MAX_VALUE 255
22 #define BATADV_THROUGHPUT_MAX_VALUE 0xFFFFFFFF
23 #define BATADV_JITTER 20
24 
25 /* Time To Live of broadcast messages */
26 #define BATADV_TTL 50
27 
28 /* maximum sequence number age of broadcast messages */
29 #define BATADV_BCAST_MAX_AGE 64
30 
31 /* purge originators after time in seconds if no valid packet comes in
32  * -> TODO: check influence on BATADV_TQ_LOCAL_WINDOW_SIZE
33  */
34 #define BATADV_PURGE_TIMEOUT 200000 /* 200 seconds */
35 #define BATADV_TT_LOCAL_TIMEOUT 600000 /* in milliseconds */
36 #define BATADV_TT_CLIENT_ROAM_TIMEOUT 600000 /* in milliseconds */
37 #define BATADV_TT_CLIENT_TEMP_TIMEOUT 600000 /* in milliseconds */
38 #define BATADV_TT_WORK_PERIOD 5000 /* 5 seconds */
39 #define BATADV_ORIG_WORK_PERIOD 1000 /* 1 second */
40 #define BATADV_MCAST_WORK_PERIOD 500 /* 0.5 seconds */
41 #define BATADV_DAT_ENTRY_TIMEOUT (5 * 60000) /* 5 mins in milliseconds */
42 /* sliding packet range of received originator messages in sequence numbers
43  * (should be a multiple of our word size)
44  */
45 #define BATADV_TQ_LOCAL_WINDOW_SIZE 64
46 /* milliseconds we have to keep pending tt_req */
47 #define BATADV_TT_REQUEST_TIMEOUT 3000
48 
49 #define BATADV_TQ_GLOBAL_WINDOW_SIZE 5
50 #define BATADV_TQ_LOCAL_BIDRECT_SEND_MINIMUM 1
51 #define BATADV_TQ_LOCAL_BIDRECT_RECV_MINIMUM 1
52 #define BATADV_TQ_TOTAL_BIDRECT_LIMIT 1
53 
54 /* B.A.T.M.A.N. V */
55 #define BATADV_THROUGHPUT_DEFAULT_VALUE 10 /* 1 Mbps */
56 #define BATADV_ELP_PROBES_PER_NODE 2
57 #define BATADV_ELP_MIN_PROBE_SIZE 200 /* bytes */
58 #define BATADV_ELP_PROBE_MAX_TX_DIFF 100 /* milliseconds */
59 #define BATADV_ELP_MAX_AGE 64
60 #define BATADV_OGM_MAX_ORIGDIFF 5
61 #define BATADV_OGM_MAX_AGE 64
62 
63 /* number of OGMs sent with the last tt diff */
64 #define BATADV_TT_OGM_APPEND_MAX 3
65 
66 /* Time in which a client can roam at most ROAMING_MAX_COUNT times in
67  * milliseconds
68  */
69 #define BATADV_ROAMING_MAX_TIME 20000
70 #define BATADV_ROAMING_MAX_COUNT 5
71 
72 #define BATADV_NO_FLAGS 0
73 
74 #define BATADV_NULL_IFINDEX 0 /* dummy ifindex used to avoid iface checks */
75 
76 #define BATADV_NO_MARK 0
77 
78 /* default interface for multi interface operation. The default interface is
79  * used for communication which originated locally (i.e. is not forwarded)
80  * or where special forwarding is not desired/necessary.
81  */
82 #define BATADV_IF_DEFAULT	((struct batadv_hard_iface *)NULL)
83 
84 #define BATADV_NUM_WORDS BITS_TO_LONGS(BATADV_TQ_LOCAL_WINDOW_SIZE)
85 
86 #define BATADV_LOG_BUF_LEN 8192	  /* has to be a power of 2 */
87 
88 /* number of packets to send for broadcasts on different interface types */
89 #define BATADV_NUM_BCASTS_DEFAULT 1
90 #define BATADV_NUM_BCASTS_WIRELESS 3
91 #define BATADV_NUM_BCASTS_MAX 3
92 
93 /* length of the single packet used by the TP meter */
94 #define BATADV_TP_PACKET_LEN ETH_DATA_LEN
95 
96 /* msecs after which an ARP_REQUEST is sent in broadcast as fallback */
97 #define ARP_REQ_DELAY 250
98 /* numbers of originator to contact for any PUT/GET DHT operation */
99 #define BATADV_DAT_CANDIDATES_NUM 3
100 
101 /* BATADV_TQ_SIMILARITY_THRESHOLD - TQ points that a secondary metric can differ
102  * at most from the primary one in order to be still considered acceptable
103  */
104 #define BATADV_TQ_SIMILARITY_THRESHOLD 50
105 
106 /* should not be bigger than 512 bytes or change the size of
107  * forw_packet->direct_link_flags
108  */
109 #define BATADV_MAX_AGGREGATION_BYTES 512
110 #define BATADV_MAX_AGGREGATION_MS 100
111 
112 #define BATADV_BLA_PERIOD_LENGTH	10000	/* 10 seconds */
113 #define BATADV_BLA_BACKBONE_TIMEOUT	(BATADV_BLA_PERIOD_LENGTH * 6)
114 #define BATADV_BLA_CLAIM_TIMEOUT	(BATADV_BLA_PERIOD_LENGTH * 10)
115 #define BATADV_BLA_WAIT_PERIODS		3
116 #define BATADV_BLA_LOOPDETECT_PERIODS	6
117 #define BATADV_BLA_LOOPDETECT_TIMEOUT	3000	/* 3 seconds */
118 
119 #define BATADV_DUPLIST_SIZE		16
120 #define BATADV_DUPLIST_TIMEOUT		500	/* 500 ms */
121 /* don't reset again within 30 seconds */
122 #define BATADV_RESET_PROTECTION_MS 30000
123 #define BATADV_EXPECTED_SEQNO_RANGE	65536
124 
125 #define BATADV_NC_NODE_TIMEOUT 10000 /* Milliseconds */
126 
127 /**
128  * BATADV_TP_MAX_NUM - maximum number of simultaneously active tp sessions
129  */
130 #define BATADV_TP_MAX_NUM 5
131 
132 /**
133  * enum batadv_mesh_state - State of a soft interface
134  */
135 enum batadv_mesh_state {
136 	/** @BATADV_MESH_INACTIVE: soft interface is not yet running */
137 	BATADV_MESH_INACTIVE,
138 
139 	/** @BATADV_MESH_ACTIVE: interface is up and running */
140 	BATADV_MESH_ACTIVE,
141 
142 	/** @BATADV_MESH_DEACTIVATING: interface is getting shut down */
143 	BATADV_MESH_DEACTIVATING,
144 };
145 
146 #define BATADV_BCAST_QUEUE_LEN		256
147 #define BATADV_BATMAN_QUEUE_LEN	256
148 
149 /**
150  * enum batadv_uev_action - action type of uevent
151  */
152 enum batadv_uev_action {
153 	/** @BATADV_UEV_ADD: gateway was selected (after none was selected) */
154 	BATADV_UEV_ADD = 0,
155 
156 	/**
157 	 * @BATADV_UEV_DEL: selected gateway was removed and none is selected
158 	 * anymore
159 	 */
160 	BATADV_UEV_DEL,
161 
162 	/**
163 	 * @BATADV_UEV_CHANGE: a different gateway was selected as based gateway
164 	 */
165 	BATADV_UEV_CHANGE,
166 
167 	/**
168 	 * @BATADV_UEV_LOOPDETECT: loop was detected which cannot be handled by
169 	 * bridge loop avoidance
170 	 */
171 	BATADV_UEV_LOOPDETECT,
172 };
173 
174 /**
175  * enum batadv_uev_type - Type of uevent
176  */
177 enum batadv_uev_type {
178 	/** @BATADV_UEV_GW: selected gateway was modified */
179 	BATADV_UEV_GW = 0,
180 
181 	/** @BATADV_UEV_BLA: bridge loop avoidance event */
182 	BATADV_UEV_BLA,
183 };
184 
185 #define BATADV_GW_THRESHOLD	50
186 
187 /* Number of fragment chains for each orig_node */
188 #define BATADV_FRAG_BUFFER_COUNT 8
189 /* Maximum number of fragments for one packet */
190 #define BATADV_FRAG_MAX_FRAGMENTS 16
191 /* Maxumim size of each fragment */
192 #define BATADV_FRAG_MAX_FRAG_SIZE 1280
193 /* Time to keep fragments while waiting for rest of the fragments */
194 #define BATADV_FRAG_TIMEOUT 10000
195 
196 #define BATADV_DAT_CANDIDATE_NOT_FOUND	0
197 #define BATADV_DAT_CANDIDATE_ORIG	1
198 
199 /* Debug Messages */
200 #ifdef pr_fmt
201 #undef pr_fmt
202 #endif
203 /* Append 'batman-adv: ' before kernel messages */
204 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
205 
206 /* Kernel headers */
207 
208 #include <linux/atomic.h>
209 #include <linux/compiler.h>
210 #include <linux/etherdevice.h>
211 #include <linux/if_vlan.h>
212 #include <linux/jiffies.h>
213 #include <linux/netdevice.h>
214 #include <linux/percpu.h>
215 #include <linux/seq_file.h>
216 #include <linux/skbuff.h>
217 #include <linux/types.h>
218 #include <uapi/linux/batadv_packet.h>
219 
220 #include "types.h"
221 #include "main.h"
222 
223 /**
224  * batadv_print_vid() - return printable version of vid information
225  * @vid: the VLAN identifier
226  *
227  * Return: -1 when no VLAN is used, VLAN id otherwise
228  */
batadv_print_vid(unsigned short vid)229 static inline int batadv_print_vid(unsigned short vid)
230 {
231 	if (vid & BATADV_VLAN_HAS_TAG)
232 		return (int)(vid & VLAN_VID_MASK);
233 	else
234 		return -1;
235 }
236 
237 extern struct list_head batadv_hardif_list;
238 extern unsigned int batadv_hardif_generation;
239 
240 extern unsigned char batadv_broadcast_addr[];
241 extern struct workqueue_struct *batadv_event_workqueue;
242 
243 int batadv_mesh_init(struct net_device *soft_iface);
244 void batadv_mesh_free(struct net_device *soft_iface);
245 bool batadv_is_my_mac(struct batadv_priv *bat_priv, const u8 *addr);
246 struct batadv_hard_iface *
247 batadv_seq_print_text_primary_if_get(struct seq_file *seq);
248 int batadv_max_header_len(void);
249 void batadv_skb_set_priority(struct sk_buff *skb, int offset);
250 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
251 			   struct packet_type *ptype,
252 			   struct net_device *orig_dev);
253 int
254 batadv_recv_handler_register(u8 packet_type,
255 			     int (*recv_handler)(struct sk_buff *,
256 						 struct batadv_hard_iface *));
257 void batadv_recv_handler_unregister(u8 packet_type);
258 __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr);
259 
260 /**
261  * batadv_compare_eth() - Compare two not u16 aligned Ethernet addresses
262  * @data1: Pointer to a six-byte array containing the Ethernet address
263  * @data2: Pointer other six-byte array containing the Ethernet address
264  *
265  * note: can't use ether_addr_equal() as it requires aligned memory
266  *
267  * Return: true if they are the same ethernet addr
268  */
batadv_compare_eth(const void * data1,const void * data2)269 static inline bool batadv_compare_eth(const void *data1, const void *data2)
270 {
271 	return ether_addr_equal_unaligned(data1, data2);
272 }
273 
274 /**
275  * batadv_has_timed_out() - compares current time (jiffies) and timestamp +
276  *  timeout
277  * @timestamp:		base value to compare with (in jiffies)
278  * @timeout:		added to base value before comparing (in milliseconds)
279  *
280  * Return: true if current time is after timestamp + timeout
281  */
batadv_has_timed_out(unsigned long timestamp,unsigned int timeout)282 static inline bool batadv_has_timed_out(unsigned long timestamp,
283 					unsigned int timeout)
284 {
285 	return time_is_before_jiffies(timestamp + msecs_to_jiffies(timeout));
286 }
287 
288 /**
289  * batadv_atomic_dec_not_zero() - Decrease unless the number is 0
290  * @v: pointer of type atomic_t
291  *
292  * Return: non-zero if v was not 0, and zero otherwise.
293  */
294 #define batadv_atomic_dec_not_zero(v)	atomic_add_unless((v), -1, 0)
295 
296 /**
297  * batadv_smallest_signed_int() - Returns the smallest signed integer in two's
298  *  complement with the sizeof x
299  * @x: type of integer
300  *
301  * Return: smallest signed integer of type
302  */
303 #define batadv_smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))
304 
305 /**
306  * batadv_seq_before() - Checks if a sequence number x is a predecessor of y
307  * @x: potential predecessor of @y
308  * @y: value to compare @x against
309  *
310  * It handles overflows/underflows and can correctly check for a predecessor
311  * unless the variable sequence number has grown by more then
312  * 2**(bitwidth(x)-1)-1.
313  *
314  * This means that for a u8 with the maximum value 255, it would think:
315  *
316  * * when adding nothing - it is neither a predecessor nor a successor
317  * * before adding more than 127 to the starting value - it is a predecessor,
318  * * when adding 128 - it is neither a predecessor nor a successor,
319  * * after adding more than 127 to the starting value - it is a successor
320  *
321  * Return: true when x is a predecessor of y, false otherwise
322  */
323 #define batadv_seq_before(x, y) ({ \
324 	typeof(x)_d1 = (x); \
325 	typeof(y)_d2 = (y); \
326 	typeof(x)_dummy = (_d1 - _d2); \
327 	(void)(&_d1 == &_d2); \
328 	_dummy > batadv_smallest_signed_int(_dummy); \
329 })
330 
331 /**
332  * batadv_seq_after() - Checks if a sequence number x is a successor of y
333  * @x: potential sucessor of @y
334  * @y: value to compare @x against
335  *
336  * It handles overflows/underflows and can correctly check for a successor
337  * unless the variable sequence number has grown by more then
338  * 2**(bitwidth(x)-1)-1.
339  *
340  * This means that for a u8 with the maximum value 255, it would think:
341  *
342  * * when adding nothing - it is neither a predecessor nor a successor
343  * * before adding more than 127 to the starting value - it is a predecessor,
344  * * when adding 128 - it is neither a predecessor nor a successor,
345  * * after adding more than 127 to the starting value - it is a successor
346  *
347  * Return: true when x is a successor of y, false otherwise
348  */
349 #define batadv_seq_after(x, y) batadv_seq_before(y, x)
350 
351 /**
352  * batadv_add_counter() - Add to per cpu statistics counter of soft interface
353  * @bat_priv: the bat priv with all the soft interface information
354  * @idx: counter index which should be modified
355  * @count: value to increase counter by
356  *
357  * Stop preemption on local cpu while incrementing the counter
358  */
batadv_add_counter(struct batadv_priv * bat_priv,size_t idx,size_t count)359 static inline void batadv_add_counter(struct batadv_priv *bat_priv, size_t idx,
360 				      size_t count)
361 {
362 	this_cpu_add(bat_priv->bat_counters[idx], count);
363 }
364 
365 /**
366  * batadv_inc_counter() - Increase per cpu statistics counter of soft interface
367  * @b: the bat priv with all the soft interface information
368  * @i: counter index which should be modified
369  */
370 #define batadv_inc_counter(b, i) batadv_add_counter(b, i, 1)
371 
372 /**
373  * BATADV_SKB_CB() - Get batadv_skb_cb from skb control buffer
374  * @__skb: skb holding the control buffer
375  *
376  * The members of the control buffer are defined in struct batadv_skb_cb in
377  * types.h. The macro is inspired by the similar macro TCP_SKB_CB() in tcp.h.
378  *
379  * Return: pointer to the batadv_skb_cb of the skb
380  */
381 #define BATADV_SKB_CB(__skb)       ((struct batadv_skb_cb *)&((__skb)->cb[0]))
382 
383 unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len);
384 bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid);
385 int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
386 			enum batadv_uev_action action, const char *data);
387 
388 #endif /* _NET_BATMAN_ADV_MAIN_H_ */
389