1 /** @file
2 @brief IPv6 data handler
3
4 This is not to be included by the application.
5 */
6
7 /*
8 * Copyright (c) 2016 Intel Corporation
9 *
10 * SPDX-License-Identifier: Apache-2.0
11 */
12
13 #ifndef __IPV6_H
14 #define __IPV6_H
15
16 #include <zephyr/types.h>
17
18 #include <zephyr/net/net_ip.h>
19 #include <zephyr/net/net_pkt.h>
20 #include <zephyr/net/net_if.h>
21 #include <zephyr/net/net_context.h>
22
23 #include "icmpv6.h"
24 #include "nbr.h"
25
26 #define NET_IPV6_ND_HOP_LIMIT 255
27 #define NET_IPV6_ND_INFINITE_LIFETIME 0xFFFFFFFF
28
29 #define NET_IPV6_DEFAULT_PREFIX_LEN 64
30
31 #define NET_MAX_RS_COUNT 3
32
33 #define NET_IPV6_DSCP_MASK 0xFC
34 #define NET_IPV6_DSCP_OFFSET 2
35 #define NET_IPV6_ECN_MASK 0x03
36
37 /**
38 * @brief Bitmaps for IPv6 extension header processing
39 *
40 * When processing extension headers, we record which one we have seen.
41 * This is done as the network packet cannot have twice the same header,
42 * except for destination option.
43 * This information is stored in bitfield variable.
44 * The order of the bitmap is the order recommended in RFC 2460.
45 */
46 #define NET_IPV6_EXT_HDR_BITMAP_HBHO 0x01
47 #define NET_IPV6_EXT_HDR_BITMAP_DESTO1 0x02
48 #define NET_IPV6_EXT_HDR_BITMAP_ROUTING 0x04
49 #define NET_IPV6_EXT_HDR_BITMAP_FRAG 0x08
50 #define NET_IPV6_EXT_HDR_BITMAP_AH 0x10
51 #define NET_IPV6_EXT_HDR_BITMAP_ESP 0x20
52 #define NET_IPV6_EXT_HDR_BITMAP_DESTO2 0x40
53
54 /**
55 * @brief Destination and Hop By Hop extension headers option types
56 */
57 #define NET_IPV6_EXT_HDR_OPT_PAD1 0
58 #define NET_IPV6_EXT_HDR_OPT_PADN 1
59 #define NET_IPV6_EXT_HDR_OPT_RPL 0x63
60
61 /**
62 * @brief Multicast Listener Record v2 record types.
63 */
64 #define NET_IPV6_MLDv2_MODE_IS_INCLUDE 1
65 #define NET_IPV6_MLDv2_MODE_IS_EXCLUDE 2
66 #define NET_IPV6_MLDv2_CHANGE_TO_INCLUDE_MODE 3
67 #define NET_IPV6_MLDv2_CHANGE_TO_EXCLUDE_MODE 4
68 #define NET_IPV6_MLDv2_ALLOW_NEW_SOURCES 5
69 #define NET_IPV6_MLDv2_BLOCK_OLD_SOURCES 6
70
71 /* State of the neighbor */
72 enum net_ipv6_nbr_state {
73 NET_IPV6_NBR_STATE_INCOMPLETE,
74 NET_IPV6_NBR_STATE_REACHABLE,
75 NET_IPV6_NBR_STATE_STALE,
76 NET_IPV6_NBR_STATE_DELAY,
77 NET_IPV6_NBR_STATE_PROBE,
78 NET_IPV6_NBR_STATE_STATIC,
79 };
80
81 const char *net_ipv6_nbr_state2str(enum net_ipv6_nbr_state state);
82
83 /**
84 * @brief IPv6 neighbor information.
85 */
86 struct net_ipv6_nbr_data {
87 /** Any pending packet waiting ND to finish. */
88 struct net_pkt *pending;
89
90 /** IPv6 address. */
91 struct in6_addr addr;
92
93 /** Reachable timer. */
94 int64_t reachable;
95
96 /** Reachable timeout */
97 int32_t reachable_timeout;
98
99 /** Neighbor Solicitation reply timer */
100 int64_t send_ns;
101
102 /** State of the neighbor discovery */
103 enum net_ipv6_nbr_state state;
104
105 /** Link metric for the neighbor */
106 uint16_t link_metric;
107
108 /** How many times we have sent NS */
109 uint8_t ns_count;
110
111 /** Is the neighbor a router */
112 bool is_router;
113
114 #if defined(CONFIG_NET_IPV6_NBR_CACHE) || defined(CONFIG_NET_IPV6_ND)
115 /** Stale counter used to removed oldest nbr in STALE state,
116 * when table is full.
117 */
118 uint32_t stale_counter;
119 #endif
120 };
121
net_ipv6_nbr_data(struct net_nbr * nbr)122 static inline struct net_ipv6_nbr_data *net_ipv6_nbr_data(struct net_nbr *nbr)
123 {
124 return (struct net_ipv6_nbr_data *)nbr->data;
125 }
126
127 #if defined(CONFIG_NET_IPV6_DAD)
128 int net_ipv6_start_dad(struct net_if *iface, struct net_if_addr *ifaddr);
129 #endif
130
131 int net_ipv6_send_ns(struct net_if *iface, struct net_pkt *pending,
132 const struct in6_addr *src, const struct in6_addr *dst,
133 const struct in6_addr *tgt, bool is_my_address);
134
135 int net_ipv6_send_rs(struct net_if *iface);
136 int net_ipv6_start_rs(struct net_if *iface);
137
138 int net_ipv6_send_na(struct net_if *iface, const struct in6_addr *src,
139 const struct in6_addr *dst, const struct in6_addr *tgt,
140 uint8_t flags);
141
142
net_ipv6_is_nexthdr_upper_layer(uint8_t nexthdr)143 static inline bool net_ipv6_is_nexthdr_upper_layer(uint8_t nexthdr)
144 {
145 return (nexthdr == IPPROTO_ICMPV6 || nexthdr == IPPROTO_UDP ||
146 nexthdr == IPPROTO_TCP ||
147 (IS_ENABLED(CONFIG_NET_L2_VIRTUAL) &&
148 ((nexthdr == IPPROTO_IPV6) || (nexthdr == IPPROTO_IPIP))));
149 }
150
151 /**
152 * @brief Create IPv6 packet in provided net_pkt.
153 *
154 * @param pkt Network packet
155 * @param src Source IPv6 address
156 * @param dst Destination IPv6 address
157 *
158 * @return 0 on success, negative errno otherwise.
159 */
160 #if defined(CONFIG_NET_NATIVE_IPV6)
161 int net_ipv6_create(struct net_pkt *pkt,
162 const struct in6_addr *src,
163 const struct in6_addr *dst);
164 #else
net_ipv6_create(struct net_pkt * pkt,const struct in6_addr * src,const struct in6_addr * dst)165 static inline int net_ipv6_create(struct net_pkt *pkt,
166 const struct in6_addr *src,
167 const struct in6_addr *dst)
168 {
169 ARG_UNUSED(pkt);
170 ARG_UNUSED(src);
171 ARG_UNUSED(dst);
172
173 return -ENOTSUP;
174 }
175 #endif
176
177 /**
178 * @brief Finalize IPv6 packet. It should be called right before
179 * sending the packet and after all the data has been added into
180 * the packet. This function will set the length of the
181 * packet and calculate the higher protocol checksum if needed.
182 *
183 * @param pkt Network packet
184 * @param next_header_proto Protocol type of the next header after IPv6 header.
185 *
186 * @return 0 on success, negative errno otherwise.
187 */
188 #if defined(CONFIG_NET_NATIVE_IPV6)
189 int net_ipv6_finalize(struct net_pkt *pkt, uint8_t next_header_proto);
190 #else
net_ipv6_finalize(struct net_pkt * pkt,uint8_t next_header_proto)191 static inline int net_ipv6_finalize(struct net_pkt *pkt,
192 uint8_t next_header_proto)
193 {
194 ARG_UNUSED(pkt);
195 ARG_UNUSED(next_header_proto);
196
197 return -ENOTSUP;
198 }
199 #endif
200
201 /**
202 * @brief Join a given multicast group.
203 *
204 * @param iface Network interface where join message is sent
205 * @param addr Multicast group to join
206 *
207 * @return Return 0 if joining was done, <0 otherwise.
208 */
209 #if defined(CONFIG_NET_IPV6_MLD)
210 int net_ipv6_mld_join(struct net_if *iface, const struct in6_addr *addr);
211 #else
212 static inline int
net_ipv6_mld_join(struct net_if * iface,const struct in6_addr * addr)213 net_ipv6_mld_join(struct net_if *iface, const struct in6_addr *addr)
214 {
215 ARG_UNUSED(iface);
216 ARG_UNUSED(addr);
217
218 return -ENOTSUP;
219 }
220 #endif /* CONFIG_NET_IPV6_MLD */
221
222 /**
223 * @brief Leave a given multicast group.
224 *
225 * @param iface Network interface where leave message is sent
226 * @param addr Multicast group to leave
227 *
228 * @return Return 0 if leaving is done, <0 otherwise.
229 */
230 #if defined(CONFIG_NET_IPV6_MLD)
231 int net_ipv6_mld_leave(struct net_if *iface, const struct in6_addr *addr);
232 #else
233 static inline int
net_ipv6_mld_leave(struct net_if * iface,const struct in6_addr * addr)234 net_ipv6_mld_leave(struct net_if *iface, const struct in6_addr *addr)
235 {
236 ARG_UNUSED(iface);
237 ARG_UNUSED(addr);
238
239 return -ENOTSUP;
240 }
241 #endif /* CONFIG_NET_IPV6_MLD */
242
243 /**
244 * @typedef net_nbr_cb_t
245 * @brief Callback used while iterating over neighbors.
246 *
247 * @param nbr A valid pointer on current neighbor.
248 * @param user_data A valid pointer on some user data or NULL
249 */
250 typedef void (*net_nbr_cb_t)(struct net_nbr *nbr, void *user_data);
251
252 /**
253 * @brief Make sure the link layer address is set according to
254 * destination address. If the ll address is not yet known, then
255 * start neighbor discovery to find it out. If ND needs to be done
256 * then the returned packet is the Neighbor Solicitation message
257 * and the original message is sent after Neighbor Advertisement
258 * message is received.
259 *
260 * @param pkt Network packet
261 *
262 * @return Return a verdict.
263 */
264 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
265 enum net_verdict net_ipv6_prepare_for_send(struct net_pkt *pkt);
266 #else
net_ipv6_prepare_for_send(struct net_pkt * pkt)267 static inline enum net_verdict net_ipv6_prepare_for_send(struct net_pkt *pkt)
268 {
269 return NET_OK;
270 }
271 #endif
272
273 /**
274 * @brief Lock IPv6 Neighbor table mutex
275 *
276 * Neighbor table mutex is used by IPv6 Neighbor cache and IPv6 Routing module.
277 * Mutex shall be held whenever accessing or manipulating neighbor or routing
278 * table entries (for example when obtaining a pointer to the neighbor table
279 * entry). Neighbor and Routing API functions will lock the mutex when called.
280 */
281 void net_ipv6_nbr_lock(void);
282
283 /**
284 * @brief Unlock IPv6 Neighbor table mutex
285 */
286 void net_ipv6_nbr_unlock(void);
287
288 /**
289 * @brief Look for a neighbor from it's address on an iface
290 *
291 * @param iface A valid pointer on a network interface
292 * @param addr The IPv6 address to match
293 *
294 * @return A valid pointer on a neighbor on success, NULL otherwise
295 */
296 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
297 struct net_nbr *net_ipv6_nbr_lookup(struct net_if *iface,
298 struct in6_addr *addr);
299 #else
net_ipv6_nbr_lookup(struct net_if * iface,struct in6_addr * addr)300 static inline struct net_nbr *net_ipv6_nbr_lookup(struct net_if *iface,
301 struct in6_addr *addr)
302 {
303 return NULL;
304 }
305 #endif
306
307 /**
308 * @brief Get neighbor from its index.
309 *
310 * @param iface Network interface to match. If NULL, then use
311 * whatever interface there is configured for the neighbor address.
312 * @param idx Index of the link layer address in the address array
313 *
314 * @return A valid pointer on a neighbor on success, NULL otherwise
315 */
316 struct net_nbr *net_ipv6_get_nbr(struct net_if *iface, uint8_t idx);
317
318 /**
319 * @brief Look for a neighbor from it's link local address index
320 *
321 * @param iface Network interface to match. If NULL, then use
322 * whatever interface there is configured for the neighbor address.
323 * @param idx Index of the link layer address in the address array
324 *
325 * @return A valid pointer on a neighbor on success, NULL otherwise
326 */
327 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
328 struct in6_addr *net_ipv6_nbr_lookup_by_index(struct net_if *iface,
329 uint8_t idx);
330 #else
331 static inline
net_ipv6_nbr_lookup_by_index(struct net_if * iface,uint8_t idx)332 struct in6_addr *net_ipv6_nbr_lookup_by_index(struct net_if *iface,
333 uint8_t idx)
334 {
335 return NULL;
336 }
337 #endif
338
339 /**
340 * @brief Add a neighbor to neighbor cache
341 *
342 * Add a neighbor to the cache after performing a lookup and in case
343 * there exists an entry in the cache update its state and lladdr.
344 *
345 * @param iface A valid pointer on a network interface
346 * @param addr Neighbor IPv6 address
347 * @param lladdr Neighbor link layer address
348 * @param is_router Set to true if the neighbor is a router, false
349 * otherwise
350 * @param state Initial state of the neighbor entry in the cache
351 *
352 * @return A valid pointer on a neighbor on success, NULL otherwise
353 */
354 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
355 struct net_nbr *net_ipv6_nbr_add(struct net_if *iface,
356 const struct in6_addr *addr,
357 const struct net_linkaddr *lladdr,
358 bool is_router,
359 enum net_ipv6_nbr_state state);
360 #else
net_ipv6_nbr_add(struct net_if * iface,const struct in6_addr * addr,const struct net_linkaddr * lladdr,bool is_router,enum net_ipv6_nbr_state state)361 static inline struct net_nbr *net_ipv6_nbr_add(struct net_if *iface,
362 const struct in6_addr *addr,
363 const struct net_linkaddr *lladdr,
364 bool is_router,
365 enum net_ipv6_nbr_state state)
366 {
367 return NULL;
368 }
369 #endif
370
371 /**
372 * @brief Remove a neighbor from neighbor cache.
373 *
374 * @param iface A valid pointer on a network interface
375 * @param addr Neighbor IPv6 address
376 *
377 * @return True if neighbor could be removed, False otherwise
378 */
379 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
380 bool net_ipv6_nbr_rm(struct net_if *iface, struct in6_addr *addr);
381 #else
net_ipv6_nbr_rm(struct net_if * iface,struct in6_addr * addr)382 static inline bool net_ipv6_nbr_rm(struct net_if *iface, struct in6_addr *addr)
383 {
384 return true;
385 }
386 #endif
387
388 /**
389 * @brief Go through all the neighbors and call callback for each of them.
390 *
391 * @param cb User supplied callback function to call.
392 * @param user_data User specified data.
393 */
394 #if defined(CONFIG_NET_IPV6_NBR_CACHE) && defined(CONFIG_NET_NATIVE_IPV6)
395 void net_ipv6_nbr_foreach(net_nbr_cb_t cb, void *user_data);
396 #else /* CONFIG_NET_IPV6_NBR_CACHE */
net_ipv6_nbr_foreach(net_nbr_cb_t cb,void * user_data)397 static inline void net_ipv6_nbr_foreach(net_nbr_cb_t cb, void *user_data)
398 {
399 return;
400 }
401 #endif /* CONFIG_NET_IPV6_NBR_CACHE */
402
403 /**
404 * @brief Provide a reachability hint for IPv6 Neighbor Discovery.
405 *
406 * This function is intended for upper-layer protocols to inform the IPv6
407 * Neighbor Discovery process about the active link to a specific neighbor.
408 * By signaling recent "forward progress" event, such as the reception of
409 * an ACK, this function can help reducing unnecessary ND traffic as per the
410 * guidelines in RFC 4861 (section 7.3).
411 *
412 * @param iface A pointer to the network interface.
413 * @param ipv6_addr Pointer to the IPv6 address of the neighbor node.
414 */
415 #if defined(CONFIG_NET_IPV6_ND) && defined(CONFIG_NET_NATIVE_IPV6)
416 void net_ipv6_nbr_reachability_hint(struct net_if *iface, const struct in6_addr *ipv6_addr);
417 #else
net_ipv6_nbr_reachability_hint(struct net_if * iface,const struct in6_addr * ipv6_addr)418 static inline void net_ipv6_nbr_reachability_hint(struct net_if *iface,
419 const struct in6_addr *ipv6_addr)
420 {
421 ARG_UNUSED(iface);
422 ARG_UNUSED(ipv6_addr);
423 }
424 #endif
425
426 /**
427 * @brief Set the neighbor reachable timer.
428 *
429 * @param iface A valid pointer on a network interface
430 * @param nbr Neighbor struct pointer
431 */
432 #if defined(CONFIG_NET_IPV6_ND) && defined(CONFIG_NET_NATIVE_IPV6)
433 void net_ipv6_nbr_set_reachable_timer(struct net_if *iface,
434 struct net_nbr *nbr);
435
436 #else /* CONFIG_NET_IPV6_ND */
net_ipv6_nbr_set_reachable_timer(struct net_if * iface,struct net_nbr * nbr)437 static inline void net_ipv6_nbr_set_reachable_timer(struct net_if *iface,
438 struct net_nbr *nbr)
439 {
440 }
441 #endif
442
443 #if defined(CONFIG_NET_IPV6_FRAGMENT)
444 /** Store pending IPv6 fragment information that is needed for reassembly. */
445 struct net_ipv6_reassembly {
446 /** IPv6 source address of the fragment */
447 struct in6_addr src;
448
449 /** IPv6 destination address of the fragment */
450 struct in6_addr dst;
451
452 /**
453 * Timeout for cancelling the reassembly. The timer is used
454 * also to detect if this reassembly slot is used or not.
455 */
456 struct k_work_delayable timer;
457
458 /** Pointers to pending fragments */
459 struct net_pkt *pkt[CONFIG_NET_IPV6_FRAGMENT_MAX_PKT];
460
461 /** IPv6 fragment identification */
462 uint32_t id;
463 };
464 #else
465 struct net_ipv6_reassembly;
466 #endif
467
468 /**
469 * @typedef net_ipv6_frag_cb_t
470 * @brief Callback used while iterating over pending IPv6 fragments.
471 *
472 * @param reass IPv6 fragment reassembly struct
473 * @param user_data A valid pointer on some user data or NULL
474 */
475 typedef void (*net_ipv6_frag_cb_t)(struct net_ipv6_reassembly *reass,
476 void *user_data);
477
478 /**
479 * @brief Go through all the currently pending IPv6 fragments.
480 *
481 * @param cb Callback to call for each pending IPv6 fragment.
482 * @param user_data User specified data or NULL.
483 */
484 void net_ipv6_frag_foreach(net_ipv6_frag_cb_t cb, void *user_data);
485
486 /**
487 * @brief Find the last IPv6 extension header in the network packet.
488 *
489 * @param pkt Network head packet.
490 * @param next_hdr_off Offset of the next header field that points
491 * to last header. This is returned to caller.
492 * @param last_hdr_off Offset of the last header field in the packet.
493 * This is returned to caller.
494 *
495 * @return 0 on success, a negative errno otherwise.
496 */
497 int net_ipv6_find_last_ext_hdr(struct net_pkt *pkt, uint16_t *next_hdr_off,
498 uint16_t *last_hdr_off);
499
500 /**
501 * @brief Handles IPv6 fragmented packets.
502 *
503 * @param pkt Network head packet.
504 * @param hdr The IPv6 header of the current packet
505 * @param nexthdr IPv6 next header after fragment header part
506 *
507 * @return Return verdict about the packet
508 */
509 #if defined(CONFIG_NET_IPV6_FRAGMENT) && defined(CONFIG_NET_NATIVE_IPV6)
510 enum net_verdict net_ipv6_handle_fragment_hdr(struct net_pkt *pkt,
511 struct net_ipv6_hdr *hdr,
512 uint8_t nexthdr);
513 #else
514 static inline
net_ipv6_handle_fragment_hdr(struct net_pkt * pkt,struct net_ipv6_hdr * hdr,uint8_t nexthdr)515 enum net_verdict net_ipv6_handle_fragment_hdr(struct net_pkt *pkt,
516 struct net_ipv6_hdr *hdr,
517 uint8_t nexthdr)
518 {
519 ARG_UNUSED(pkt);
520 ARG_UNUSED(hdr);
521 ARG_UNUSED(nexthdr);
522
523 return NET_DROP;
524 }
525 #endif /* CONFIG_NET_IPV6_FRAGMENT */
526
527 #if defined(CONFIG_NET_NATIVE_IPV6)
528 void net_ipv6_init(void);
529 void net_ipv6_nbr_init(void);
530 #if defined(CONFIG_NET_IPV6_MLD)
531 void net_ipv6_mld_init(void);
532 #else
533 #define net_ipv6_mld_init(...)
534 #endif
535 #else
536 #define net_ipv6_init(...)
537 #define net_ipv6_nbr_init(...)
538 #endif
539
540 /**
541 * @brief Decode DSCP value from TC field.
542 *
543 * @param tc TC field value from the IPv6 header.
544 *
545 * @return Decoded DSCP value.
546 */
net_ipv6_get_dscp(uint8_t tc)547 static inline uint8_t net_ipv6_get_dscp(uint8_t tc)
548 {
549 return (tc & NET_IPV6_DSCP_MASK) >> NET_IPV6_DSCP_OFFSET;
550 }
551
552 /**
553 * @brief Encode DSCP value into TC field.
554 *
555 * @param tc A pointer to the TC field.
556 * @param dscp DSCP value to set.
557 */
net_ipv6_set_dscp(uint8_t * tc,uint8_t dscp)558 static inline void net_ipv6_set_dscp(uint8_t *tc, uint8_t dscp)
559 {
560 *tc &= ~NET_IPV6_DSCP_MASK;
561 *tc |= (dscp << NET_IPV6_DSCP_OFFSET) & NET_IPV6_DSCP_MASK;
562 }
563
564 /**
565 * @brief Convert DSCP value to priority.
566 *
567 * @param dscp DSCP value.
568 */
net_ipv6_dscp_to_priority(uint8_t dscp)569 static inline uint8_t net_ipv6_dscp_to_priority(uint8_t dscp)
570 {
571 return dscp >> 3;
572 }
573
574 /**
575 * @brief Decode ECN value from TC field.
576 *
577 * @param tc TC field value from the IPv6 header.
578 *
579 * @return Decoded ECN value.
580 */
net_ipv6_get_ecn(uint8_t tc)581 static inline uint8_t net_ipv6_get_ecn(uint8_t tc)
582 {
583 return tc & NET_IPV6_ECN_MASK;
584 }
585
586 /**
587 * @brief Encode ECN value into TC field.
588 *
589 * @param tc A pointer to the TC field.
590 * @param ecn ECN value to set.
591 */
net_ipv6_set_ecn(uint8_t * tc,uint8_t ecn)592 static inline void net_ipv6_set_ecn(uint8_t *tc, uint8_t ecn)
593 {
594 *tc &= ~NET_IPV6_ECN_MASK;
595 *tc |= ecn & NET_IPV6_ECN_MASK;
596 }
597
598
599 #endif /* __IPV6_H */
600
