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1 /**
2  * @file
3  * lwIP network interface abstraction
4  *
5  * @defgroup netif Network interface (NETIF)
6  * @ingroup callbackstyle_api
7  *
8  * @defgroup netif_ip4 IPv4 address handling
9  * @ingroup netif
10  *
11  * @defgroup netif_ip6 IPv6 address handling
12  * @ingroup netif
13  *
14  * @defgroup netif_cd Client data handling
15  * Store data (void*) on a netif for application usage.
16  * @see @ref LWIP_NUM_NETIF_CLIENT_DATA
17  * @ingroup netif
18  */
19 
20 /*
21  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
22  * All rights reserved.
23  *
24  * Redistribution and use in source and binary forms, with or without modification,
25  * are permitted provided that the following conditions are met:
26  *
27  * 1. Redistributions of source code must retain the above copyright notice,
28  *    this list of conditions and the following disclaimer.
29  * 2. Redistributions in binary form must reproduce the above copyright notice,
30  *    this list of conditions and the following disclaimer in the documentation
31  *    and/or other materials provided with the distribution.
32  * 3. The name of the author may not be used to endorse or promote products
33  *    derived from this software without specific prior written permission.
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
36  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
37  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
38  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
39  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
40  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
41  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
42  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
43  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
44  * OF SUCH DAMAGE.
45  *
46  * This file is part of the lwIP TCP/IP stack.
47  *
48  * Author: Adam Dunkels <adam@sics.se>
49  */
50 
51 #include "lwip/opt.h"
52 
53 #include <string.h> /* memset */
54 #include <stdlib.h> /* atoi */
55 
56 #include "lwip/def.h"
57 #include "lwip/ip_addr.h"
58 #include "lwip/ip6_addr.h"
59 #include "lwip/netif.h"
60 #include "lwip/priv/tcp_priv.h"
61 #include "lwip/udp.h"
62 #include "lwip/priv/raw_priv.h"
63 #include "lwip/snmp.h"
64 #include "lwip/igmp.h"
65 #include "lwip/etharp.h"
66 #include "lwip/stats.h"
67 #include "lwip/sys.h"
68 #include "lwip/ip.h"
69 #if ENABLE_LOOPBACK
70 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
71 #include "lwip/tcpip.h"
72 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
73 #endif /* ENABLE_LOOPBACK */
74 
75 #include "netif/ethernet.h"
76 
77 #if LWIP_AUTOIP
78 #include "lwip/autoip.h"
79 #endif /* LWIP_AUTOIP */
80 #if LWIP_DHCP
81 #include "lwip/dhcp.h"
82 #endif /* LWIP_DHCP */
83 #if LWIP_IPV6_DHCP6
84 #include "lwip/dhcp6.h"
85 #endif /* LWIP_IPV6_DHCP6 */
86 #if LWIP_IPV6_MLD
87 #include "lwip/mld6.h"
88 #endif /* LWIP_IPV6_MLD */
89 #if LWIP_IPV6
90 #include "lwip/nd6.h"
91 #endif
92 
93 #if LWIP_NETIF_STATUS_CALLBACK
94 #define NETIF_STATUS_CALLBACK(n) do{ if (n->status_callback) { (n->status_callback)(n); }}while(0)
95 #else
96 #define NETIF_STATUS_CALLBACK(n)
97 #endif /* LWIP_NETIF_STATUS_CALLBACK */
98 
99 #if LWIP_NETIF_LINK_CALLBACK
100 #define NETIF_LINK_CALLBACK(n) do{ if (n->link_callback) { (n->link_callback)(n); }}while(0)
101 #else
102 #define NETIF_LINK_CALLBACK(n)
103 #endif /* LWIP_NETIF_LINK_CALLBACK */
104 
105 #if LWIP_NETIF_EXT_STATUS_CALLBACK
106 static netif_ext_callback_t *ext_callback;
107 #endif
108 
109 #ifndef LOSCFG_NET_CONTAINER
110 #if !LWIP_SINGLE_NETIF
111 struct netif *netif_list;
112 #endif /* !LWIP_SINGLE_NETIF */
113 struct netif *netif_default;
114 #endif
115 
116 #define netif_index_to_num(index)   ((index) - 1)
117 #ifndef LOSCFG_NET_CONTAINER
118 static u8_t netif_num;
119 #endif
120 
121 #if LWIP_NUM_NETIF_CLIENT_DATA > 0
122 static u8_t netif_client_id;
123 #endif
124 
125 #define NETIF_REPORT_TYPE_IPV4  0x01
126 #define NETIF_REPORT_TYPE_IPV6  0x02
127 static void netif_issue_reports(struct netif *netif, u8_t report_type);
128 
129 #if LWIP_IPV6
130 static err_t netif_null_output_ip6(struct netif *netif, struct pbuf *p, const ip6_addr_t *ipaddr);
131 #endif /* LWIP_IPV6 */
132 #if LWIP_IPV4
133 static err_t netif_null_output_ip4(struct netif *netif, struct pbuf *p, const ip4_addr_t *ipaddr);
134 #endif /* LWIP_IPV4 */
135 
136 #if LWIP_HAVE_LOOPIF
137 #if LWIP_IPV4
138 static err_t netif_loop_output_ipv4(struct netif *netif, struct pbuf *p, const ip4_addr_t *addr);
139 #endif
140 #if LWIP_IPV6
141 static err_t netif_loop_output_ipv6(struct netif *netif, struct pbuf *p, const ip6_addr_t *addr);
142 #endif
143 
144 
145 #ifdef LOSCFG_NET_CONTAINER
get_net_group_from_netif(struct netif * netif)146 struct net_group *get_net_group_from_netif(struct netif *netif) {
147   if (netif != NULL) {
148     return get_default_net_group_ops()->get_net_group_from_netif(netif);
149   }
150   return NULL;
151 }
152 #else
153 static struct netif loop_netif;
154 #endif
155 
156 /**
157  * Initialize a lwip network interface structure for a loopback interface
158  *
159  * @param netif the lwip network interface structure for this loopif
160  * @return ERR_OK if the loopif is initialized
161  *         ERR_MEM if private data couldn't be allocated
162  */
163 static err_t
netif_loopif_init(struct netif * netif)164 netif_loopif_init(struct netif *netif)
165 {
166   LWIP_ASSERT("netif_loopif_init: invalid netif", netif != NULL);
167 
168   /* initialize the snmp variables and counters inside the struct netif
169    * ifSpeed: no assumption can be made!
170    */
171   MIB2_INIT_NETIF(netif, snmp_ifType_softwareLoopback, 0);
172 
173   netif->name[0] = 'l';
174   netif->name[1] = 'o';
175 #if LWIP_IPV4
176   netif->output = netif_loop_output_ipv4;
177 #endif
178 #if LWIP_IPV6
179   netif->output_ip6 = netif_loop_output_ipv6;
180 #endif
181 #if LWIP_LOOPIF_MULTICAST
182   netif_set_flags(netif, NETIF_FLAG_IGMP);
183 #endif
184   NETIF_SET_CHECKSUM_CTRL(netif, NETIF_CHECKSUM_DISABLE_ALL);
185   return ERR_OK;
186 }
187 #endif /* LWIP_HAVE_LOOPIF */
188 
189 void
190 #ifdef LOSCFG_NET_CONTAINER
netif_init(struct net_group * group)191 netif_init(struct net_group *group)
192 #else
193 netif_init(void)
194 #endif
195 {
196 #if LWIP_HAVE_LOOPIF
197 #if LWIP_IPV4
198 #define LOOPIF_ADDRINIT &loop_ipaddr, &loop_netmask, &loop_gw,
199   ip4_addr_t loop_ipaddr, loop_netmask, loop_gw;
200   IP4_ADDR(&loop_gw, 127, 0, 0, 1);
201   IP4_ADDR(&loop_ipaddr, 127, 0, 0, 1);
202   IP4_ADDR(&loop_netmask, 255, 0, 0, 0);
203 #else /* LWIP_IPV4 */
204 #define LOOPIF_ADDRINIT
205 #endif /* LWIP_IPV4 */
206 
207 #ifdef LOSCFG_NET_CONTAINER
208 struct netif *loop_netif = group->loop_netif;
209 #endif
210 
211 #if NO_SYS
212 #ifdef LOSCFG_NET_CONTAINER
213   netif_add(loop_netif, group, LOOPIF_ADDRINIT NULL, netif_loopif_init, ip_input);
214 #else
215   netif_add(&loop_netif, LOOPIF_ADDRINIT NULL, netif_loopif_init, ip_input);
216 #endif
217 #else  /* NO_SYS */
218 #ifdef LOSCFG_NET_CONTAINER
219   netif_add(loop_netif, group, LOOPIF_ADDRINIT NULL, netif_loopif_init, tcpip_input);
220 #else
221   netif_add(&loop_netif, LOOPIF_ADDRINIT NULL, netif_loopif_init, tcpip_input);
222 #endif
223 #endif /* NO_SYS */
224 
225 #if LWIP_IPV6
226 #ifdef LOSCFG_NET_CONTAINER
227   IP_ADDR6_HOST(loop_netif->ip6_addr, 0, 0, 0, 0x00000001UL);
228   loop_netif->ip6_addr_state[0] = IP6_ADDR_VALID;
229 #else
230   IP_ADDR6_HOST(loop_netif.ip6_addr, 0, 0, 0, 0x00000001UL);
231   loop_netif.ip6_addr_state[0] = IP6_ADDR_VALID;
232 #endif
233 #endif /* LWIP_IPV6 */
234 
235 #ifdef LOSCFG_NET_CONTAINER
236   netif_set_link_up(loop_netif);
237   netif_set_up(loop_netif);
238 #else
239   netif_set_link_up(&loop_netif);
240   netif_set_up(&loop_netif);
241 #endif
242 
243 #endif /* LWIP_HAVE_LOOPIF */
244 }
245 
246 /**
247  * @ingroup lwip_nosys
248  * Forwards a received packet for input processing with
249  * ethernet_input() or ip_input() depending on netif flags.
250  * Don't call directly, pass to netif_add() and call
251  * netif->input().
252  * Only works if the netif driver correctly sets
253  * NETIF_FLAG_ETHARP and/or NETIF_FLAG_ETHERNET flag!
254  */
255 err_t
netif_input(struct pbuf * p,struct netif * inp)256 netif_input(struct pbuf *p, struct netif *inp)
257 {
258   LWIP_ASSERT_CORE_LOCKED();
259 
260   LWIP_ASSERT("netif_input: invalid pbuf", p != NULL);
261   LWIP_ASSERT("netif_input: invalid netif", inp != NULL);
262 
263 #if LWIP_ETHERNET
264   if (inp->flags & (NETIF_FLAG_ETHARP | NETIF_FLAG_ETHERNET)) {
265     return ethernet_input(p, inp);
266   } else
267 #endif /* LWIP_ETHERNET */
268     return ip_input(p, inp);
269 }
270 
271 /**
272  * @ingroup netif
273  * Add a network interface to the list of lwIP netifs.
274  *
275  * Same as @ref netif_add but without IPv4 addresses
276  */
277 struct netif *
278 #ifdef LOSCFG_NET_CONTAINER
netif_add_noaddr(struct netif * netif,struct net_group * group,void * state,netif_init_fn init,netif_input_fn input)279 netif_add_noaddr(struct netif *netif, struct net_group *group, void *state, netif_init_fn init, netif_input_fn input)
280 #else
281 netif_add_noaddr(struct netif *netif, void *state, netif_init_fn init, netif_input_fn input)
282 #endif
283 {
284 #ifdef LOSCFG_NET_CONTAINER
285   return netif_add(netif, group,
286 #else
287   return netif_add(netif,
288 #endif
289 #if LWIP_IPV4
290                    NULL, NULL, NULL,
291 #endif /* LWIP_IPV4*/
292                    state, init, input);
293 }
294 
295 /**
296  * @ingroup netif
297  * Add a network interface to the list of lwIP netifs.
298  *
299  * @param netif a pre-allocated netif structure
300  * @param ipaddr IP address for the new netif
301  * @param netmask network mask for the new netif
302  * @param gw default gateway IP address for the new netif
303  * @param state opaque data passed to the new netif
304  * @param init callback function that initializes the interface
305  * @param input callback function that is called to pass
306  * ingress packets up in the protocol layer stack.\n
307  * It is recommended to use a function that passes the input directly
308  * to the stack (netif_input(), NO_SYS=1 mode) or via sending a
309  * message to TCPIP thread (tcpip_input(), NO_SYS=0 mode).\n
310  * These functions use netif flags NETIF_FLAG_ETHARP and NETIF_FLAG_ETHERNET
311  * to decide whether to forward to ethernet_input() or ip_input().
312  * In other words, the functions only work when the netif
313  * driver is implemented correctly!\n
314  * Most members of struct netif should be be initialized by the
315  * netif init function = netif driver (init parameter of this function).\n
316  * IPv6: Don't forget to call netif_create_ip6_linklocal_address() after
317  * setting the MAC address in struct netif.hwaddr
318  * (IPv6 requires a link-local address).
319  *
320  * @return netif, or NULL if failed.
321  */
322 struct netif *
323 #ifdef LOSCFG_NET_CONTAINER
netif_add(struct netif * netif,struct net_group * group,const ip4_addr_t * ipaddr,const ip4_addr_t * netmask,const ip4_addr_t * gw,void * state,netif_init_fn init,netif_input_fn input)324 netif_add(struct netif *netif, struct net_group *group,
325 #else
326 netif_add(struct netif *netif,
327 #endif
328 #if LWIP_IPV4
329           const ip4_addr_t *ipaddr, const ip4_addr_t *netmask, const ip4_addr_t *gw,
330 #endif /* LWIP_IPV4 */
331           void *state, netif_init_fn init, netif_input_fn input)
332 {
333 #if LWIP_IPV6
334   s8_t i;
335 #endif
336 
337   LWIP_ASSERT_CORE_LOCKED();
338 
339 #ifdef LOSCFG_NET_CONTAINER
340   get_default_net_group_ops()->set_netif_net_group(netif, group);
341 #endif
342 
343 #if LWIP_SINGLE_NETIF
344 #ifdef LOSCFG_NET_CONTAINER
345   if (group->loop_netif != NULL) {
346 #else
347   if (netif_default != NULL) {
348 #endif
349     LWIP_ASSERT("single netif already set", 0);
350     return NULL;
351   }
352 #endif
353 
354   LWIP_ERROR("netif_add: invalid netif", netif != NULL, return NULL);
355   LWIP_ERROR("netif_add: No init function given", init != NULL, return NULL);
356 
357 #if LWIP_IPV4
358   if (ipaddr == NULL) {
359     ipaddr = ip_2_ip4(IP4_ADDR_ANY);
360   }
361   if (netmask == NULL) {
362     netmask = ip_2_ip4(IP4_ADDR_ANY);
363   }
364   if (gw == NULL) {
365     gw = ip_2_ip4(IP4_ADDR_ANY);
366   }
367 
368   /* reset new interface configuration state */
369   ip_addr_set_zero_ip4(&netif->ip_addr);
370   ip_addr_set_zero_ip4(&netif->netmask);
371   ip_addr_set_zero_ip4(&netif->gw);
372   netif->output = netif_null_output_ip4;
373 #endif /* LWIP_IPV4 */
374 #if LWIP_IPV6
375   for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
376     ip_addr_set_zero_ip6(&netif->ip6_addr[i]);
377     netif->ip6_addr_state[i] = IP6_ADDR_INVALID;
378 #if LWIP_IPV6_ADDRESS_LIFETIMES
379     netif->ip6_addr_valid_life[i] = IP6_ADDR_LIFE_STATIC;
380     netif->ip6_addr_pref_life[i] = IP6_ADDR_LIFE_STATIC;
381 #endif /* LWIP_IPV6_ADDRESS_LIFETIMES */
382   }
383   netif->output_ip6 = netif_null_output_ip6;
384 #endif /* LWIP_IPV6 */
385   NETIF_SET_CHECKSUM_CTRL(netif, NETIF_CHECKSUM_ENABLE_ALL);
386   netif->mtu = 0;
387   netif->flags = 0;
388 #ifdef netif_get_client_data
389   memset(netif->client_data, 0, sizeof(netif->client_data));
390 #endif /* LWIP_NUM_NETIF_CLIENT_DATA */
391 #if LWIP_IPV6
392 #if LWIP_IPV6_AUTOCONFIG
393   /* IPv6 address autoconfiguration not enabled by default */
394   netif->ip6_autoconfig_enabled = 0;
395 #endif /* LWIP_IPV6_AUTOCONFIG */
396   nd6_restart_netif(netif);
397 #endif /* LWIP_IPV6 */
398 #if LWIP_NETIF_STATUS_CALLBACK
399   netif->status_callback = NULL;
400 #endif /* LWIP_NETIF_STATUS_CALLBACK */
401 #if LWIP_NETIF_LINK_CALLBACK
402   netif->link_callback = NULL;
403 #endif /* LWIP_NETIF_LINK_CALLBACK */
404 #if LWIP_IGMP
405   netif->igmp_mac_filter = NULL;
406 #endif /* LWIP_IGMP */
407 #if LWIP_IPV6 && LWIP_IPV6_MLD
408   netif->mld_mac_filter = NULL;
409 #endif /* LWIP_IPV6 && LWIP_IPV6_MLD */
410 
411   /* remember netif specific state information data */
412   netif->state = state;
413 #ifdef LOSCFG_NET_CONTAINER
414   netif->num = group->netif_num;
415 #else
416   netif->num = netif_num;
417 #endif
418   netif->input = input;
419 
420   NETIF_RESET_HINTS(netif);
421 #if ENABLE_LOOPBACK
422   netif->loop_first = NULL;
423   netif->loop_last = NULL;
424 #if LWIP_LOOPBACK_MAX_PBUFS
425   netif->loop_cnt_current = 0;
426 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
427 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
428   netif->reschedule_poll = 0;
429 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
430 #endif /* ENABLE_LOOPBACK */
431 
432 #if LWIP_IPV4
433   netif_set_addr(netif, ipaddr, netmask, gw);
434 #endif /* LWIP_IPV4 */
435 
436   /* call user specified initialization function for netif */
437   if (init(netif) != ERR_OK) {
438     return NULL;
439   }
440 #if LWIP_IPV6 && LWIP_ND6_ALLOW_RA_UPDATES
441   /* Initialize the MTU for IPv6 to the one set by the netif driver.
442      This can be updated later by RA. */
443   netif->mtu6 = netif->mtu;
444 #endif /* LWIP_IPV6 && LWIP_ND6_ALLOW_RA_UPDATES */
445 
446 #if !LWIP_SINGLE_NETIF
447   /* Assign a unique netif number in the range [0..254], so that (num+1) can
448      serve as an interface index that fits in a u8_t.
449      We assume that the new netif has not yet been added to the list here.
450      This algorithm is O(n^2), but that should be OK for lwIP.
451      */
452   {
453     struct netif *netif2;
454     int num_netifs;
455     do {
456       if (netif->num == 255) {
457         netif->num = 0;
458       }
459       num_netifs = 0;
460 #ifdef LOSCFG_NET_CONTAINER
461       for (netif2 = group->netif_list; netif2 != NULL; netif2 = netif2->next) {
462 #else
463       for (netif2 = netif_list; netif2 != NULL; netif2 = netif2->next) {
464 #endif
465         LWIP_ASSERT("netif already added", netif2 != netif);
466         num_netifs++;
467         LWIP_ASSERT("too many netifs, max. supported number is 255", num_netifs <= 255);
468         if (netif2->num == netif->num) {
469           netif->num++;
470           break;
471         }
472       }
473     } while (netif2 != NULL);
474   }
475   if (netif->num == 254) {
476 #ifdef LOSCFG_NET_CONTAINER
477     group->netif_num = 0;
478 #else
479     netif_num = 0;
480 #endif
481   } else {
482 #ifdef LOSCFG_NET_CONTAINER
483     group->netif_num = (u8_t)(netif->num + 1);
484 #else
485     netif_num = (u8_t)(netif->num + 1);
486 #endif
487   }
488 
489   /* add this netif to the list */
490 #ifdef LOSCFG_NET_CONTAINER
491   netif->next = group->netif_list;
492   group->netif_list = netif;
493 #else
494   netif->next = netif_list;
495   netif_list = netif;
496 #endif
497 #endif /* "LWIP_SINGLE_NETIF */
498   mib2_netif_added(netif);
499 
500 #if LWIP_IGMP
501   /* start IGMP processing */
502   if (netif->flags & NETIF_FLAG_IGMP) {
503     igmp_start(netif);
504   }
505 #endif /* LWIP_IGMP */
506 
507   LWIP_DEBUGF(NETIF_DEBUG, ("netif: added interface %c%c IP",
508                             netif->name[0], netif->name[1]));
509 #if LWIP_IPV4
510   LWIP_DEBUGF(NETIF_DEBUG, (" addr "));
511   ip4_addr_debug_print(NETIF_DEBUG, ipaddr);
512   LWIP_DEBUGF(NETIF_DEBUG, (" netmask "));
513   ip4_addr_debug_print(NETIF_DEBUG, netmask);
514   LWIP_DEBUGF(NETIF_DEBUG, (" gw "));
515   ip4_addr_debug_print(NETIF_DEBUG, gw);
516 #endif /* LWIP_IPV4 */
517   LWIP_DEBUGF(NETIF_DEBUG, ("\n"));
518 
519   netif_invoke_ext_callback(netif, LWIP_NSC_NETIF_ADDED, NULL);
520 
521   return netif;
522 }
523 
524 static void
525 netif_do_ip_addr_changed(const ip_addr_t *old_addr, const ip_addr_t *new_addr)
526 {
527 #if LWIP_TCP
528   tcp_netif_ip_addr_changed(old_addr, new_addr);
529 #endif /* LWIP_TCP */
530 #if LWIP_UDP
531   udp_netif_ip_addr_changed(old_addr, new_addr);
532 #endif /* LWIP_UDP */
533 #if LWIP_RAW
534   raw_netif_ip_addr_changed(old_addr, new_addr);
535 #endif /* LWIP_RAW */
536 }
537 
538 #if LWIP_IPV4
539 static int
540 netif_do_set_ipaddr(struct netif *netif, const ip4_addr_t *ipaddr, ip_addr_t *old_addr)
541 {
542   LWIP_ASSERT("invalid pointer", ipaddr != NULL);
543   LWIP_ASSERT("invalid pointer", old_addr != NULL);
544 
545   /* address is actually being changed? */
546   if (ip4_addr_cmp(ipaddr, netif_ip4_addr(netif)) == 0) {
547     ip_addr_t new_addr;
548     *ip_2_ip4(&new_addr) = *ipaddr;
549     IP_SET_TYPE_VAL(new_addr, IPADDR_TYPE_V4);
550 
551     ip_addr_copy(*old_addr, *netif_ip_addr4(netif));
552 
553     LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: netif address being changed\n"));
554     netif_do_ip_addr_changed(old_addr, &new_addr);
555 
556     mib2_remove_ip4(netif);
557     mib2_remove_route_ip4(0, netif);
558     /* set new IP address to netif */
559     ip4_addr_set(ip_2_ip4(&netif->ip_addr), ipaddr);
560     IP_SET_TYPE_VAL(netif->ip_addr, IPADDR_TYPE_V4);
561     mib2_add_ip4(netif);
562     mib2_add_route_ip4(0, netif);
563 
564     netif_issue_reports(netif, NETIF_REPORT_TYPE_IPV4);
565 
566     NETIF_STATUS_CALLBACK(netif);
567     return 1; /* address changed */
568   }
569   return 0; /* address unchanged */
570 }
571 
572 /**
573  * @ingroup netif_ip4
574  * Change the IP address of a network interface
575  *
576  * @param netif the network interface to change
577  * @param ipaddr the new IP address
578  *
579  * @note call netif_set_addr() if you also want to change netmask and
580  * default gateway
581  */
582 void
583 netif_set_ipaddr(struct netif *netif, const ip4_addr_t *ipaddr)
584 {
585   ip_addr_t old_addr;
586 
587   LWIP_ERROR("netif_set_ipaddr: invalid netif", netif != NULL, return);
588 
589   /* Don't propagate NULL pointer (IPv4 ANY) to subsequent functions */
590   if (ipaddr == NULL) {
591     ipaddr = IP4_ADDR_ANY4;
592   }
593 
594   LWIP_ASSERT_CORE_LOCKED();
595 
596   if (netif_do_set_ipaddr(netif, ipaddr, &old_addr)) {
597 #if LWIP_NETIF_EXT_STATUS_CALLBACK
598     netif_ext_callback_args_t args;
599     args.ipv4_changed.old_address = &old_addr;
600     netif_invoke_ext_callback(netif, LWIP_NSC_IPV4_ADDRESS_CHANGED, &args);
601 #endif
602   }
603 }
604 
605 static int
606 netif_do_set_netmask(struct netif *netif, const ip4_addr_t *netmask, ip_addr_t *old_nm)
607 {
608   /* address is actually being changed? */
609   if (ip4_addr_cmp(netmask, netif_ip4_netmask(netif)) == 0) {
610 #if LWIP_NETIF_EXT_STATUS_CALLBACK
611     LWIP_ASSERT("invalid pointer", old_nm != NULL);
612     ip_addr_copy(*old_nm, *netif_ip_netmask4(netif));
613 #else
614     LWIP_UNUSED_ARG(old_nm);
615 #endif
616     mib2_remove_route_ip4(0, netif);
617     /* set new netmask to netif */
618     ip4_addr_set(ip_2_ip4(&netif->netmask), netmask);
619     IP_SET_TYPE_VAL(netif->netmask, IPADDR_TYPE_V4);
620     mib2_add_route_ip4(0, netif);
621     LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: netmask of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
622                 netif->name[0], netif->name[1],
623                 ip4_addr1_16(netif_ip4_netmask(netif)),
624                 ip4_addr2_16(netif_ip4_netmask(netif)),
625                 ip4_addr3_16(netif_ip4_netmask(netif)),
626                 ip4_addr4_16(netif_ip4_netmask(netif))));
627     return 1; /* netmask changed */
628   }
629   return 0; /* netmask unchanged */
630 }
631 
632 /**
633  * @ingroup netif_ip4
634  * Change the netmask of a network interface
635  *
636  * @param netif the network interface to change
637  * @param netmask the new netmask
638  *
639  * @note call netif_set_addr() if you also want to change ip address and
640  * default gateway
641  */
642 void
643 netif_set_netmask(struct netif *netif, const ip4_addr_t *netmask)
644 {
645 #if LWIP_NETIF_EXT_STATUS_CALLBACK
646   ip_addr_t old_nm_val;
647   ip_addr_t *old_nm = &old_nm_val;
648 #else
649   ip_addr_t *old_nm = NULL;
650 #endif
651   LWIP_ASSERT_CORE_LOCKED();
652 
653   LWIP_ERROR("netif_set_netmask: invalid netif", netif != NULL, return);
654 
655   /* Don't propagate NULL pointer (IPv4 ANY) to subsequent functions */
656   if (netmask == NULL) {
657     netmask = IP4_ADDR_ANY4;
658   }
659 
660   if (netif_do_set_netmask(netif, netmask, old_nm)) {
661 #if LWIP_NETIF_EXT_STATUS_CALLBACK
662     netif_ext_callback_args_t args;
663     args.ipv4_changed.old_netmask = old_nm;
664     netif_invoke_ext_callback(netif, LWIP_NSC_IPV4_NETMASK_CHANGED, &args);
665 #endif
666   }
667 }
668 
669 static int
670 netif_do_set_gw(struct netif *netif, const ip4_addr_t *gw, ip_addr_t *old_gw)
671 {
672   /* address is actually being changed? */
673   if (ip4_addr_cmp(gw, netif_ip4_gw(netif)) == 0) {
674 #if LWIP_NETIF_EXT_STATUS_CALLBACK
675     LWIP_ASSERT("invalid pointer", old_gw != NULL);
676     ip_addr_copy(*old_gw, *netif_ip_gw4(netif));
677 #else
678     LWIP_UNUSED_ARG(old_gw);
679 #endif
680 
681     ip4_addr_set(ip_2_ip4(&netif->gw), gw);
682     IP_SET_TYPE_VAL(netif->gw, IPADDR_TYPE_V4);
683     LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: GW address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
684                 netif->name[0], netif->name[1],
685                 ip4_addr1_16(netif_ip4_gw(netif)),
686                 ip4_addr2_16(netif_ip4_gw(netif)),
687                 ip4_addr3_16(netif_ip4_gw(netif)),
688                 ip4_addr4_16(netif_ip4_gw(netif))));
689     return 1; /* gateway changed */
690   }
691   return 0; /* gateway unchanged */
692 }
693 
694 /**
695  * @ingroup netif_ip4
696  * Change the default gateway for a network interface
697  *
698  * @param netif the network interface to change
699  * @param gw the new default gateway
700  *
701  * @note call netif_set_addr() if you also want to change ip address and netmask
702  */
703 void
704 netif_set_gw(struct netif *netif, const ip4_addr_t *gw)
705 {
706 #if LWIP_NETIF_EXT_STATUS_CALLBACK
707   ip_addr_t old_gw_val;
708   ip_addr_t *old_gw = &old_gw_val;
709 #else
710   ip_addr_t *old_gw = NULL;
711 #endif
712   LWIP_ASSERT_CORE_LOCKED();
713 
714   LWIP_ERROR("netif_set_gw: invalid netif", netif != NULL, return);
715 
716   /* Don't propagate NULL pointer (IPv4 ANY) to subsequent functions */
717   if (gw == NULL) {
718     gw = IP4_ADDR_ANY4;
719   }
720 
721   if (netif_do_set_gw(netif, gw, old_gw)) {
722 #if LWIP_NETIF_EXT_STATUS_CALLBACK
723     netif_ext_callback_args_t args;
724     args.ipv4_changed.old_gw = old_gw;
725     netif_invoke_ext_callback(netif, LWIP_NSC_IPV4_GATEWAY_CHANGED, &args);
726 #endif
727   }
728 }
729 
730 /**
731  * @ingroup netif_ip4
732  * Change IP address configuration for a network interface (including netmask
733  * and default gateway).
734  *
735  * @param netif the network interface to change
736  * @param ipaddr the new IP address
737  * @param netmask the new netmask
738  * @param gw the new default gateway
739  */
740 void
741 netif_set_addr(struct netif *netif, const ip4_addr_t *ipaddr, const ip4_addr_t *netmask,
742                const ip4_addr_t *gw)
743 {
744 #if LWIP_NETIF_EXT_STATUS_CALLBACK
745   netif_nsc_reason_t change_reason = LWIP_NSC_NONE;
746   netif_ext_callback_args_t cb_args;
747   ip_addr_t old_nm_val;
748   ip_addr_t old_gw_val;
749   ip_addr_t *old_nm = &old_nm_val;
750   ip_addr_t *old_gw = &old_gw_val;
751 #else
752   ip_addr_t *old_nm = NULL;
753   ip_addr_t *old_gw = NULL;
754 #endif
755   ip_addr_t old_addr;
756   int remove;
757 
758   LWIP_ASSERT_CORE_LOCKED();
759 
760   /* Don't propagate NULL pointer (IPv4 ANY) to subsequent functions */
761   if (ipaddr == NULL) {
762     ipaddr = IP4_ADDR_ANY4;
763   }
764   if (netmask == NULL) {
765     netmask = IP4_ADDR_ANY4;
766   }
767   if (gw == NULL) {
768     gw = IP4_ADDR_ANY4;
769   }
770 
771   remove = ip4_addr_isany(ipaddr);
772   if (remove) {
773     /* when removing an address, we have to remove it *before* changing netmask/gw
774        to ensure that tcp RST segment can be sent correctly */
775     if (netif_do_set_ipaddr(netif, ipaddr, &old_addr)) {
776 #if LWIP_NETIF_EXT_STATUS_CALLBACK
777       change_reason |= LWIP_NSC_IPV4_ADDRESS_CHANGED;
778       cb_args.ipv4_changed.old_address = &old_addr;
779 #endif
780     }
781   }
782   if (netif_do_set_netmask(netif, netmask, old_nm)) {
783 #if LWIP_NETIF_EXT_STATUS_CALLBACK
784     change_reason |= LWIP_NSC_IPV4_NETMASK_CHANGED;
785     cb_args.ipv4_changed.old_netmask = old_nm;
786 #endif
787   }
788   if (netif_do_set_gw(netif, gw, old_gw)) {
789 #if LWIP_NETIF_EXT_STATUS_CALLBACK
790     change_reason |= LWIP_NSC_IPV4_GATEWAY_CHANGED;
791     cb_args.ipv4_changed.old_gw = old_gw;
792 #endif
793   }
794   if (!remove) {
795     /* set ipaddr last to ensure netmask/gw have been set when status callback is called */
796     if (netif_do_set_ipaddr(netif, ipaddr, &old_addr)) {
797 #if LWIP_NETIF_EXT_STATUS_CALLBACK
798       change_reason |= LWIP_NSC_IPV4_ADDRESS_CHANGED;
799       cb_args.ipv4_changed.old_address = &old_addr;
800 #endif
801     }
802   }
803 
804 #if LWIP_NETIF_EXT_STATUS_CALLBACK
805   if (change_reason != LWIP_NSC_NONE) {
806     change_reason |= LWIP_NSC_IPV4_SETTINGS_CHANGED;
807     netif_invoke_ext_callback(netif, change_reason, &cb_args);
808   }
809 #endif
810 }
811 #endif /* LWIP_IPV4*/
812 
813 /**
814  * @ingroup netif
815  * Remove a network interface from the list of lwIP netifs.
816  *
817  * @param netif the network interface to remove
818  */
819 void
820 netif_remove(struct netif *netif)
821 {
822 #if LWIP_IPV6
823   int i;
824 #endif
825 
826   LWIP_ASSERT_CORE_LOCKED();
827 
828   if (netif == NULL) {
829     return;
830   }
831 #ifdef LOSCFG_NET_CONTAINER
832   struct net_group *group = get_net_group_from_netif(netif);
833 
834   if (group == NULL) {
835     return;
836   }
837 #endif
838   netif_invoke_ext_callback(netif, LWIP_NSC_NETIF_REMOVED, NULL);
839 
840 #if LWIP_IPV4
841   if (!ip4_addr_isany_val(*netif_ip4_addr(netif))) {
842     netif_do_ip_addr_changed(netif_ip_addr4(netif), NULL);
843   }
844 
845 #if LWIP_IGMP
846   /* stop IGMP processing */
847   if (netif->flags & NETIF_FLAG_IGMP) {
848     igmp_stop(netif);
849   }
850 #endif /* LWIP_IGMP */
851 #endif /* LWIP_IPV4*/
852 
853 #if LWIP_IPV6
854   for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
855     if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i))) {
856       netif_do_ip_addr_changed(netif_ip_addr6(netif, i), NULL);
857     }
858   }
859 #if LWIP_IPV6_MLD
860   /* stop MLD processing */
861   mld6_stop(netif);
862 #endif /* LWIP_IPV6_MLD */
863 #endif /* LWIP_IPV6 */
864   if (netif_is_up(netif)) {
865     /* set netif down before removing (call callback function) */
866     netif_set_down(netif);
867   }
868 
869   mib2_remove_ip4(netif);
870 
871   /* this netif is default? */
872 #ifdef LOSCFG_NET_CONTAINER
873   if (group->netif_default == netif) {
874 #else
875   if (netif_default == netif) {
876 #endif
877     /* reset default netif */
878 #ifdef LOSCFG_NET_CONTAINER
879     netif_set_default(NULL, group);
880 #else
881     netif_set_default(NULL);
882 #endif
883   }
884 #if !LWIP_SINGLE_NETIF
885   /*  is it the first netif? */
886 #ifdef LOSCFG_NET_CONTAINER
887   if (group->netif_list == netif) {
888     group->netif_list = netif->next;
889 #else
890   if (netif_list == netif) {
891     netif_list = netif->next;
892 #endif
893   } else {
894     /*  look for netif further down the list */
895     struct netif *tmp_netif;
896 #ifdef LOSCFG_NET_CONTAINER
897     NETIF_FOREACH(tmp_netif, group) {
898 #else
899     NETIF_FOREACH(tmp_netif) {
900 #endif
901       if (tmp_netif->next == netif) {
902         tmp_netif->next = netif->next;
903         break;
904       }
905     }
906     if (tmp_netif == NULL) {
907       return; /* netif is not on the list */
908     }
909   }
910 #endif /* !LWIP_SINGLE_NETIF */
911   mib2_netif_removed(netif);
912 #if LWIP_NETIF_REMOVE_CALLBACK
913   if (netif->remove_callback) {
914     netif->remove_callback(netif);
915   }
916 #endif /* LWIP_NETIF_REMOVE_CALLBACK */
917   LWIP_DEBUGF( NETIF_DEBUG, ("netif_remove: removed netif\n") );
918 }
919 
920 /**
921  * @ingroup netif
922  * Set a network interface as the default network interface
923  * (used to output all packets for which no specific route is found)
924  *
925  * @param netif the default network interface
926  */
927 void
928 #ifdef LOSCFG_NET_CONTAINER
929 netif_set_default(struct netif *netif, struct net_group *group)
930 #else
931 netif_set_default(struct netif *netif)
932 #endif
933 {
934   LWIP_ASSERT_CORE_LOCKED();
935 
936   if (netif == NULL) {
937     /* remove default route */
938     mib2_remove_route_ip4(1, netif);
939   } else {
940     /* install default route */
941     mib2_add_route_ip4(1, netif);
942   }
943 #ifdef LOSCFG_NET_CONTAINER
944   group->netif_default = netif;
945 #else
946   netif_default = netif;
947 #endif
948   LWIP_DEBUGF(NETIF_DEBUG, ("netif: setting default interface %c%c\n",
949                             netif ? netif->name[0] : '\'', netif ? netif->name[1] : '\''));
950 }
951 
952 #ifdef LOSCFG_NET_CONTAINER
953 void
954 netif_set_default2(struct netif *netif)
955 {
956     netif_set_default(netif, get_curr_process_net_group());
957 }
958 #endif
959 /**
960  * @ingroup netif
961  * Bring an interface up, available for processing
962  * traffic.
963  */
964 void
965 netif_set_up(struct netif *netif)
966 {
967   LWIP_ASSERT_CORE_LOCKED();
968 
969   LWIP_ERROR("netif_set_up: invalid netif", netif != NULL, return);
970 
971   if (!(netif->flags & NETIF_FLAG_UP)) {
972     netif_set_flags(netif, NETIF_FLAG_UP);
973 
974     MIB2_COPY_SYSUPTIME_TO(&netif->ts);
975 
976     NETIF_STATUS_CALLBACK(netif);
977 
978 #if LWIP_NETIF_EXT_STATUS_CALLBACK
979     {
980       netif_ext_callback_args_t args;
981       args.status_changed.state = 1;
982       netif_invoke_ext_callback(netif, LWIP_NSC_STATUS_CHANGED, &args);
983     }
984 #endif
985 
986     netif_issue_reports(netif, NETIF_REPORT_TYPE_IPV4 | NETIF_REPORT_TYPE_IPV6);
987 #if LWIP_IPV6
988     nd6_restart_netif(netif);
989 #endif /* LWIP_IPV6 */
990   }
991 }
992 
993 /** Send ARP/IGMP/MLD/RS events, e.g. on link-up/netif-up or addr-change
994  */
995 static void
996 netif_issue_reports(struct netif *netif, u8_t report_type)
997 {
998   LWIP_ASSERT("netif_issue_reports: invalid netif", netif != NULL);
999 
1000   /* Only send reports when both link and admin states are up */
1001   if (!(netif->flags & NETIF_FLAG_LINK_UP) ||
1002       !(netif->flags & NETIF_FLAG_UP)) {
1003     return;
1004   }
1005 
1006 #if LWIP_IPV4
1007   if ((report_type & NETIF_REPORT_TYPE_IPV4) &&
1008       !ip4_addr_isany_val(*netif_ip4_addr(netif))) {
1009 #if LWIP_ARP
1010     /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */
1011     if (netif->flags & (NETIF_FLAG_ETHARP)) {
1012       etharp_gratuitous(netif);
1013     }
1014 #endif /* LWIP_ARP */
1015 
1016 #if LWIP_IGMP
1017     /* resend IGMP memberships */
1018     if (netif->flags & NETIF_FLAG_IGMP) {
1019       igmp_report_groups(netif);
1020     }
1021 #endif /* LWIP_IGMP */
1022   }
1023 #endif /* LWIP_IPV4 */
1024 
1025 #if LWIP_IPV6
1026   if (report_type & NETIF_REPORT_TYPE_IPV6) {
1027 #if LWIP_IPV6_MLD
1028     /* send mld memberships */
1029     mld6_report_groups(netif);
1030 #endif /* LWIP_IPV6_MLD */
1031   }
1032 #endif /* LWIP_IPV6 */
1033 }
1034 
1035 /**
1036  * @ingroup netif
1037  * Bring an interface down, disabling any traffic processing.
1038  */
1039 void
1040 netif_set_down(struct netif *netif)
1041 {
1042   LWIP_ASSERT_CORE_LOCKED();
1043 
1044   LWIP_ERROR("netif_set_down: invalid netif", netif != NULL, return);
1045 
1046   if (netif->flags & NETIF_FLAG_UP) {
1047 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1048     {
1049       netif_ext_callback_args_t args;
1050       args.status_changed.state = 0;
1051       netif_invoke_ext_callback(netif, LWIP_NSC_STATUS_CHANGED, &args);
1052     }
1053 #endif
1054 
1055     netif_clear_flags(netif, NETIF_FLAG_UP);
1056     MIB2_COPY_SYSUPTIME_TO(&netif->ts);
1057 
1058 #if LWIP_IPV4 && LWIP_ARP
1059     if (netif->flags & NETIF_FLAG_ETHARP) {
1060       etharp_cleanup_netif(netif);
1061     }
1062 #endif /* LWIP_IPV4 && LWIP_ARP */
1063 
1064 #if LWIP_IPV6
1065     nd6_cleanup_netif(netif);
1066 #endif /* LWIP_IPV6 */
1067 
1068     NETIF_STATUS_CALLBACK(netif);
1069   }
1070 }
1071 
1072 #if LWIP_NETIF_STATUS_CALLBACK
1073 /**
1074  * @ingroup netif
1075  * Set callback to be called when interface is brought up/down or address is changed while up
1076  */
1077 void
1078 netif_set_status_callback(struct netif *netif, netif_status_callback_fn status_callback)
1079 {
1080   LWIP_ASSERT_CORE_LOCKED();
1081 
1082   if (netif) {
1083     netif->status_callback = status_callback;
1084   }
1085 }
1086 #endif /* LWIP_NETIF_STATUS_CALLBACK */
1087 
1088 #if LWIP_NETIF_REMOVE_CALLBACK
1089 /**
1090  * @ingroup netif
1091  * Set callback to be called when the interface has been removed
1092  */
1093 void
1094 netif_set_remove_callback(struct netif *netif, netif_status_callback_fn remove_callback)
1095 {
1096   LWIP_ASSERT_CORE_LOCKED();
1097 
1098   if (netif) {
1099     netif->remove_callback = remove_callback;
1100   }
1101 }
1102 #endif /* LWIP_NETIF_REMOVE_CALLBACK */
1103 
1104 /**
1105  * @ingroup netif
1106  * Called by a driver when its link goes up
1107  */
1108 void
1109 netif_set_link_up(struct netif *netif)
1110 {
1111   LWIP_ASSERT_CORE_LOCKED();
1112 
1113   LWIP_ERROR("netif_set_link_up: invalid netif", netif != NULL, return);
1114 
1115   if (!(netif->flags & NETIF_FLAG_LINK_UP)) {
1116     netif_set_flags(netif, NETIF_FLAG_LINK_UP);
1117 
1118 #if LWIP_DHCP
1119     dhcp_network_changed(netif);
1120 #endif /* LWIP_DHCP */
1121 
1122 #if LWIP_AUTOIP
1123     autoip_network_changed(netif);
1124 #endif /* LWIP_AUTOIP */
1125 
1126     netif_issue_reports(netif, NETIF_REPORT_TYPE_IPV4 | NETIF_REPORT_TYPE_IPV6);
1127 #if LWIP_IPV6
1128     nd6_restart_netif(netif);
1129 #endif /* LWIP_IPV6 */
1130 
1131     NETIF_LINK_CALLBACK(netif);
1132 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1133     {
1134       netif_ext_callback_args_t args;
1135       args.link_changed.state = 1;
1136       netif_invoke_ext_callback(netif, LWIP_NSC_LINK_CHANGED, &args);
1137     }
1138 #endif
1139   }
1140 }
1141 
1142 /**
1143  * @ingroup netif
1144  * Called by a driver when its link goes down
1145  */
1146 void
1147 netif_set_link_down(struct netif *netif)
1148 {
1149   LWIP_ASSERT_CORE_LOCKED();
1150 
1151   LWIP_ERROR("netif_set_link_down: invalid netif", netif != NULL, return);
1152 
1153   if (netif->flags & NETIF_FLAG_LINK_UP) {
1154     netif_clear_flags(netif, NETIF_FLAG_LINK_UP);
1155 #if LWIP_IPV6 && LWIP_ND6_ALLOW_RA_UPDATES
1156     netif->mtu6 = netif->mtu;
1157 #endif
1158 
1159     NETIF_LINK_CALLBACK(netif);
1160 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1161     {
1162       netif_ext_callback_args_t args;
1163       args.link_changed.state = 0;
1164       netif_invoke_ext_callback(netif, LWIP_NSC_LINK_CHANGED, &args);
1165     }
1166 #endif
1167   }
1168 }
1169 
1170 #if LWIP_NETIF_LINK_CALLBACK
1171 /**
1172  * @ingroup netif
1173  * Set callback to be called when link is brought up/down
1174  */
1175 void
1176 netif_set_link_callback(struct netif *netif, netif_status_callback_fn link_callback)
1177 {
1178   LWIP_ASSERT_CORE_LOCKED();
1179 
1180   if (netif) {
1181     netif->link_callback = link_callback;
1182   }
1183 }
1184 #endif /* LWIP_NETIF_LINK_CALLBACK */
1185 
1186 #if ENABLE_LOOPBACK
1187 /**
1188  * @ingroup netif
1189  * Send an IP packet to be received on the same netif (loopif-like).
1190  * The pbuf is copied and added to an internal queue which is fed to
1191  * netif->input by netif_poll().
1192  * In multithreaded mode, the call to netif_poll() is queued to be done on the
1193  * TCP/IP thread.
1194  * In callback mode, the user has the responsibility to call netif_poll() in
1195  * the main loop of their application.
1196  *
1197  * @param netif the lwip network interface structure
1198  * @param p the (IP) packet to 'send'
1199  * @return ERR_OK if the packet has been sent
1200  *         ERR_MEM if the pbuf used to copy the packet couldn't be allocated
1201  */
1202 err_t
1203 netif_loop_output(struct netif *netif, struct pbuf *p)
1204 {
1205   struct pbuf *r;
1206   err_t err;
1207   struct pbuf *last;
1208 #if LWIP_LOOPBACK_MAX_PBUFS
1209   u16_t clen = 0;
1210 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
1211   /* If we have a loopif, SNMP counters are adjusted for it,
1212    * if not they are adjusted for 'netif'. */
1213 #if MIB2_STATS
1214 #if LWIP_HAVE_LOOPIF
1215 #ifdef LOSCFG_NET_CONTAINER
1216   struct netif *stats_if = get_net_group_from_netif(netif)->loop_netif;
1217 #else
1218   struct netif *stats_if = &loop_netif;
1219 #endif
1220 #else /* LWIP_HAVE_LOOPIF */
1221   struct netif *stats_if = netif;
1222 #endif /* LWIP_HAVE_LOOPIF */
1223 #endif /* MIB2_STATS */
1224 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
1225   u8_t schedule_poll = 0;
1226 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
1227   SYS_ARCH_DECL_PROTECT(lev);
1228 
1229   LWIP_ASSERT("netif_loop_output: invalid netif", netif != NULL);
1230   LWIP_ASSERT("netif_loop_output: invalid pbuf", p != NULL);
1231 
1232   /* Allocate a new pbuf */
1233   r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
1234   if (r == NULL) {
1235     LINK_STATS_INC(link.memerr);
1236     LINK_STATS_INC(link.drop);
1237     MIB2_STATS_NETIF_INC(stats_if, ifoutdiscards);
1238     return ERR_MEM;
1239   }
1240 #if LWIP_LOOPBACK_MAX_PBUFS
1241   clen = pbuf_clen(r);
1242   /* check for overflow or too many pbuf on queue */
1243   if (((netif->loop_cnt_current + clen) < netif->loop_cnt_current) ||
1244       ((netif->loop_cnt_current + clen) > LWIP_MIN(LWIP_LOOPBACK_MAX_PBUFS, 0xFFFF))) {
1245     pbuf_free(r);
1246     LINK_STATS_INC(link.memerr);
1247     LINK_STATS_INC(link.drop);
1248     MIB2_STATS_NETIF_INC(stats_if, ifoutdiscards);
1249     return ERR_MEM;
1250   }
1251   netif->loop_cnt_current = (u16_t)(netif->loop_cnt_current + clen);
1252 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
1253 
1254   /* Copy the whole pbuf queue p into the single pbuf r */
1255   if ((err = pbuf_copy(r, p)) != ERR_OK) {
1256     pbuf_free(r);
1257     LINK_STATS_INC(link.memerr);
1258     LINK_STATS_INC(link.drop);
1259     MIB2_STATS_NETIF_INC(stats_if, ifoutdiscards);
1260     return err;
1261   }
1262 
1263   /* Put the packet on a linked list which gets emptied through calling
1264      netif_poll(). */
1265 
1266   /* let last point to the last pbuf in chain r */
1267   for (last = r; last->next != NULL; last = last->next) {
1268     /* nothing to do here, just get to the last pbuf */
1269   }
1270 
1271   SYS_ARCH_PROTECT(lev);
1272   if (netif->loop_first != NULL) {
1273     LWIP_ASSERT("if first != NULL, last must also be != NULL", netif->loop_last != NULL);
1274     netif->loop_last->next = r;
1275     netif->loop_last = last;
1276 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
1277     if (netif->reschedule_poll) {
1278       schedule_poll = 1;
1279       netif->reschedule_poll = 0;
1280     }
1281 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
1282   } else {
1283     netif->loop_first = r;
1284     netif->loop_last = last;
1285 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
1286     /* No existing packets queued, schedule poll */
1287     schedule_poll = 1;
1288 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
1289   }
1290   SYS_ARCH_UNPROTECT(lev);
1291 
1292   LINK_STATS_INC(link.xmit);
1293   MIB2_STATS_NETIF_ADD(stats_if, ifoutoctets, p->tot_len);
1294   MIB2_STATS_NETIF_INC(stats_if, ifoutucastpkts);
1295 
1296 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
1297   /* For multithreading environment, schedule a call to netif_poll */
1298   if (schedule_poll) {
1299     if (tcpip_try_callback((tcpip_callback_fn)netif_poll, netif) != ERR_OK) {
1300       SYS_ARCH_PROTECT(lev);
1301       netif->reschedule_poll = 1;
1302       SYS_ARCH_UNPROTECT(lev);
1303     }
1304   }
1305 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
1306 
1307   return ERR_OK;
1308 }
1309 
1310 #if LWIP_HAVE_LOOPIF
1311 #if LWIP_IPV4
1312 static err_t
1313 netif_loop_output_ipv4(struct netif *netif, struct pbuf *p, const ip4_addr_t *addr)
1314 {
1315   LWIP_UNUSED_ARG(addr);
1316   return netif_loop_output(netif, p);
1317 }
1318 #endif /* LWIP_IPV4 */
1319 
1320 #if LWIP_IPV6
1321 static err_t
1322 netif_loop_output_ipv6(struct netif *netif, struct pbuf *p, const ip6_addr_t *addr)
1323 {
1324   LWIP_UNUSED_ARG(addr);
1325   return netif_loop_output(netif, p);
1326 }
1327 #endif /* LWIP_IPV6 */
1328 #endif /* LWIP_HAVE_LOOPIF */
1329 
1330 
1331 /**
1332  * Call netif_poll() in the main loop of your application. This is to prevent
1333  * reentering non-reentrant functions like tcp_input(). Packets passed to
1334  * netif_loop_output() are put on a list that is passed to netif->input() by
1335  * netif_poll().
1336  */
1337 void
1338 netif_poll(struct netif *netif)
1339 {
1340   /* If we have a loopif, SNMP counters are adjusted for it,
1341    * if not they are adjusted for 'netif'. */
1342 #if MIB2_STATS
1343 #if LWIP_HAVE_LOOPIF
1344 #ifdef LOSCFG_NET_CONTAINER
1345   struct netif *stats_if = get_net_group_from_netif(netif)->loop_netif;
1346 #else
1347   struct netif *stats_if = &loop_netif;
1348 #endif
1349 #else /* LWIP_HAVE_LOOPIF */
1350   struct netif *stats_if = netif;
1351 #endif /* LWIP_HAVE_LOOPIF */
1352 #endif /* MIB2_STATS */
1353   SYS_ARCH_DECL_PROTECT(lev);
1354 
1355   LWIP_ASSERT("netif_poll: invalid netif", netif != NULL);
1356 
1357   /* Get a packet from the list. With SYS_LIGHTWEIGHT_PROT=1, this is protected */
1358   SYS_ARCH_PROTECT(lev);
1359   while (netif->loop_first != NULL) {
1360     struct pbuf *in, *in_end;
1361 #if LWIP_LOOPBACK_MAX_PBUFS
1362     u8_t clen = 1;
1363 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
1364 
1365     in = in_end = netif->loop_first;
1366     while (in_end->len != in_end->tot_len) {
1367       LWIP_ASSERT("bogus pbuf: len != tot_len but next == NULL!", in_end->next != NULL);
1368       in_end = in_end->next;
1369 #if LWIP_LOOPBACK_MAX_PBUFS
1370       clen++;
1371 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
1372     }
1373 #if LWIP_LOOPBACK_MAX_PBUFS
1374     /* adjust the number of pbufs on queue */
1375     LWIP_ASSERT("netif->loop_cnt_current underflow",
1376                 ((netif->loop_cnt_current - clen) < netif->loop_cnt_current));
1377     netif->loop_cnt_current = (u16_t)(netif->loop_cnt_current - clen);
1378 #endif /* LWIP_LOOPBACK_MAX_PBUFS */
1379 
1380     /* 'in_end' now points to the last pbuf from 'in' */
1381     if (in_end == netif->loop_last) {
1382       /* this was the last pbuf in the list */
1383       netif->loop_first = netif->loop_last = NULL;
1384     } else {
1385       /* pop the pbuf off the list */
1386       netif->loop_first = in_end->next;
1387       LWIP_ASSERT("should not be null since first != last!", netif->loop_first != NULL);
1388     }
1389     /* De-queue the pbuf from its successors on the 'loop_' list. */
1390     in_end->next = NULL;
1391     SYS_ARCH_UNPROTECT(lev);
1392 
1393     in->if_idx = netif_get_index(netif);
1394 
1395     LINK_STATS_INC(link.recv);
1396     MIB2_STATS_NETIF_ADD(stats_if, ifinoctets, in->tot_len);
1397     MIB2_STATS_NETIF_INC(stats_if, ifinucastpkts);
1398     /* loopback packets are always IP packets! */
1399     if (ip_input(in, netif) != ERR_OK) {
1400       pbuf_free(in);
1401     }
1402     SYS_ARCH_PROTECT(lev);
1403   }
1404   SYS_ARCH_UNPROTECT(lev);
1405 }
1406 
1407 #if !LWIP_NETIF_LOOPBACK_MULTITHREADING
1408 /**
1409  * Calls netif_poll() for every netif on the netif_list.
1410  */
1411 void
1412 netif_poll_all(void)
1413 {
1414   struct netif *netif;
1415   /* loop through netifs */
1416   NETIF_FOREACH(netif) {
1417     netif_poll(netif);
1418   }
1419 }
1420 #endif /* !LWIP_NETIF_LOOPBACK_MULTITHREADING */
1421 #endif /* ENABLE_LOOPBACK */
1422 
1423 #if LWIP_NUM_NETIF_CLIENT_DATA > 0
1424 /**
1425  * @ingroup netif_cd
1426  * Allocate an index to store data in client_data member of struct netif.
1427  * Returned value is an index in mentioned array.
1428  * @see LWIP_NUM_NETIF_CLIENT_DATA
1429  */
1430 u8_t
1431 netif_alloc_client_data_id(void)
1432 {
1433   u8_t result = netif_client_id;
1434   netif_client_id++;
1435 
1436   LWIP_ASSERT_CORE_LOCKED();
1437 
1438 #if LWIP_NUM_NETIF_CLIENT_DATA > 256
1439 #error LWIP_NUM_NETIF_CLIENT_DATA must be <= 256
1440 #endif
1441   LWIP_ASSERT("Increase LWIP_NUM_NETIF_CLIENT_DATA in lwipopts.h", result < LWIP_NUM_NETIF_CLIENT_DATA);
1442   return (u8_t)(result + LWIP_NETIF_CLIENT_DATA_INDEX_MAX);
1443 }
1444 #endif
1445 
1446 #if LWIP_IPV6
1447 /**
1448  * @ingroup netif_ip6
1449  * Change an IPv6 address of a network interface
1450  *
1451  * @param netif the network interface to change
1452  * @param addr_idx index of the IPv6 address
1453  * @param addr6 the new IPv6 address
1454  *
1455  * @note call netif_ip6_addr_set_state() to set the address valid/temptative
1456  */
1457 void
1458 netif_ip6_addr_set(struct netif *netif, s8_t addr_idx, const ip6_addr_t *addr6)
1459 {
1460   LWIP_ASSERT_CORE_LOCKED();
1461 
1462   LWIP_ASSERT("netif_ip6_addr_set: invalid netif", netif != NULL);
1463   LWIP_ASSERT("netif_ip6_addr_set: invalid addr6", addr6 != NULL);
1464 
1465   netif_ip6_addr_set_parts(netif, addr_idx, addr6->addr[0], addr6->addr[1],
1466                            addr6->addr[2], addr6->addr[3]);
1467 }
1468 
1469 /*
1470  * Change an IPv6 address of a network interface (internal version taking 4 * u32_t)
1471  *
1472  * @param netif the network interface to change
1473  * @param addr_idx index of the IPv6 address
1474  * @param i0 word0 of the new IPv6 address
1475  * @param i1 word1 of the new IPv6 address
1476  * @param i2 word2 of the new IPv6 address
1477  * @param i3 word3 of the new IPv6 address
1478  */
1479 void
1480 netif_ip6_addr_set_parts(struct netif *netif, s8_t addr_idx, u32_t i0, u32_t i1, u32_t i2, u32_t i3)
1481 {
1482   ip_addr_t old_addr;
1483   ip_addr_t new_ipaddr;
1484   LWIP_ASSERT_CORE_LOCKED();
1485   LWIP_ASSERT("netif != NULL", netif != NULL);
1486   LWIP_ASSERT("invalid index", addr_idx < LWIP_IPV6_NUM_ADDRESSES);
1487 
1488   ip6_addr_copy(*ip_2_ip6(&old_addr), *netif_ip6_addr(netif, addr_idx));
1489   IP_SET_TYPE_VAL(old_addr, IPADDR_TYPE_V6);
1490 
1491   /* address is actually being changed? */
1492   if ((ip_2_ip6(&old_addr)->addr[0] != i0) || (ip_2_ip6(&old_addr)->addr[1] != i1) ||
1493       (ip_2_ip6(&old_addr)->addr[2] != i2) || (ip_2_ip6(&old_addr)->addr[3] != i3)) {
1494     LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_ip6_addr_set: netif address being changed\n"));
1495 
1496     IP_ADDR6(&new_ipaddr, i0, i1, i2, i3);
1497     ip6_addr_assign_zone(ip_2_ip6(&new_ipaddr), IP6_UNICAST, netif);
1498 
1499     if (ip6_addr_isvalid(netif_ip6_addr_state(netif, addr_idx))) {
1500       netif_do_ip_addr_changed(netif_ip_addr6(netif, addr_idx), &new_ipaddr);
1501     }
1502     /* @todo: remove/readd mib2 ip6 entries? */
1503 
1504     ip_addr_copy(netif->ip6_addr[addr_idx], new_ipaddr);
1505 
1506     if (ip6_addr_isvalid(netif_ip6_addr_state(netif, addr_idx))) {
1507       netif_issue_reports(netif, NETIF_REPORT_TYPE_IPV6);
1508       NETIF_STATUS_CALLBACK(netif);
1509     }
1510 
1511 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1512     {
1513       netif_ext_callback_args_t args;
1514       args.ipv6_set.addr_index  = addr_idx;
1515       args.ipv6_set.old_address = &old_addr;
1516       netif_invoke_ext_callback(netif, LWIP_NSC_IPV6_SET, &args);
1517     }
1518 #endif
1519   }
1520 
1521   LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: IPv6 address %d of interface %c%c set to %s/0x%"X8_F"\n",
1522               addr_idx, netif->name[0], netif->name[1], ip6addr_ntoa(netif_ip6_addr(netif, addr_idx)),
1523               netif_ip6_addr_state(netif, addr_idx)));
1524 }
1525 
1526 /**
1527  * @ingroup netif_ip6
1528  * Change the state of an IPv6 address of a network interface
1529  * (INVALID, TEMPTATIVE, PREFERRED, DEPRECATED, where TEMPTATIVE
1530  * includes the number of checks done, see ip6_addr.h)
1531  *
1532  * @param netif the network interface to change
1533  * @param addr_idx index of the IPv6 address
1534  * @param state the new IPv6 address state
1535  */
1536 void
1537 netif_ip6_addr_set_state(struct netif *netif, s8_t addr_idx, u8_t state)
1538 {
1539   u8_t old_state;
1540   LWIP_ASSERT_CORE_LOCKED();
1541   LWIP_ASSERT("netif != NULL", netif != NULL);
1542   LWIP_ASSERT("invalid index", addr_idx < LWIP_IPV6_NUM_ADDRESSES);
1543 
1544   old_state = netif_ip6_addr_state(netif, addr_idx);
1545   /* state is actually being changed? */
1546   if (old_state != state) {
1547     u8_t old_valid = old_state & IP6_ADDR_VALID;
1548     u8_t new_valid = state & IP6_ADDR_VALID;
1549     LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_ip6_addr_set_state: netif address state being changed\n"));
1550 
1551 #if LWIP_IPV6_MLD
1552     /* Reevaluate solicited-node multicast group membership. */
1553     if (netif->flags & NETIF_FLAG_MLD6) {
1554       nd6_adjust_mld_membership(netif, addr_idx, state);
1555     }
1556 #endif /* LWIP_IPV6_MLD */
1557 
1558     if (old_valid && !new_valid) {
1559       /* address about to be removed by setting invalid */
1560       netif_do_ip_addr_changed(netif_ip_addr6(netif, addr_idx), NULL);
1561       /* @todo: remove mib2 ip6 entries? */
1562     }
1563     netif->ip6_addr_state[addr_idx] = state;
1564 
1565     if (!old_valid && new_valid) {
1566       /* address added by setting valid */
1567       /* This is a good moment to check that the address is properly zoned. */
1568       IP6_ADDR_ZONECHECK_NETIF(netif_ip6_addr(netif, addr_idx), netif);
1569       /* @todo: add mib2 ip6 entries? */
1570       netif_issue_reports(netif, NETIF_REPORT_TYPE_IPV6);
1571     }
1572     if ((old_state & ~IP6_ADDR_TENTATIVE_COUNT_MASK) !=
1573         (state     & ~IP6_ADDR_TENTATIVE_COUNT_MASK)) {
1574       /* address state has changed -> call the callback function */
1575       NETIF_STATUS_CALLBACK(netif);
1576     }
1577 
1578 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1579     {
1580       netif_ext_callback_args_t args;
1581       args.ipv6_addr_state_changed.addr_index = addr_idx;
1582       args.ipv6_addr_state_changed.old_state  = old_state;
1583       args.ipv6_addr_state_changed.address    = netif_ip_addr6(netif, addr_idx);
1584       netif_invoke_ext_callback(netif, LWIP_NSC_IPV6_ADDR_STATE_CHANGED, &args);
1585     }
1586 #endif
1587   }
1588   LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: IPv6 address %d of interface %c%c set to %s/0x%"X8_F"\n",
1589               addr_idx, netif->name[0], netif->name[1], ip6addr_ntoa(netif_ip6_addr(netif, addr_idx)),
1590               netif_ip6_addr_state(netif, addr_idx)));
1591 }
1592 
1593 /**
1594  * Checks if a specific local address is present on the netif and returns its
1595  * index. Depending on its state, it may or may not be assigned to the
1596  * interface (as per RFC terminology).
1597  *
1598  * The given address may or may not be zoned (i.e., have a zone index other
1599  * than IP6_NO_ZONE). If the address is zoned, it must have the correct zone
1600  * for the given netif, or no match will be found.
1601  *
1602  * @param netif the netif to check
1603  * @param ip6addr the IPv6 address to find
1604  * @return >= 0: address found, this is its index
1605  *         -1: address not found on this netif
1606  */
1607 s8_t
1608 netif_get_ip6_addr_match(struct netif *netif, const ip6_addr_t *ip6addr)
1609 {
1610   s8_t i;
1611 
1612   LWIP_ASSERT_CORE_LOCKED();
1613 
1614   LWIP_ASSERT("netif_get_ip6_addr_match: invalid netif", netif != NULL);
1615   LWIP_ASSERT("netif_get_ip6_addr_match: invalid ip6addr", ip6addr != NULL);
1616 
1617 #if LWIP_IPV6_SCOPES
1618   if (ip6_addr_has_zone(ip6addr) && !ip6_addr_test_zone(ip6addr, netif)) {
1619     return -1; /* wrong zone, no match */
1620   }
1621 #endif /* LWIP_IPV6_SCOPES */
1622 
1623   for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
1624     if (!ip6_addr_isinvalid(netif_ip6_addr_state(netif, i)) &&
1625         ip6_addr_cmp_zoneless(netif_ip6_addr(netif, i), ip6addr)) {
1626       return i;
1627     }
1628   }
1629   return -1;
1630 }
1631 
1632 /**
1633  * @ingroup netif_ip6
1634  * Create a link-local IPv6 address on a netif (stored in slot 0)
1635  *
1636  * @param netif the netif to create the address on
1637  * @param from_mac_48bit if != 0, assume hwadr is a 48-bit MAC address (std conversion)
1638  *                       if == 0, use hwaddr directly as interface ID
1639  */
1640 void
1641 netif_create_ip6_linklocal_address(struct netif *netif, u8_t from_mac_48bit)
1642 {
1643   u8_t i, addr_index;
1644 
1645   LWIP_ASSERT_CORE_LOCKED();
1646 
1647   LWIP_ASSERT("netif_create_ip6_linklocal_address: invalid netif", netif != NULL);
1648 
1649   /* Link-local prefix. */
1650   ip_2_ip6(&netif->ip6_addr[0])->addr[0] = PP_HTONL(0xfe800000ul);
1651   ip_2_ip6(&netif->ip6_addr[0])->addr[1] = 0;
1652 
1653   /* Generate interface ID. */
1654   if (from_mac_48bit) {
1655     /* Assume hwaddr is a 48-bit IEEE 802 MAC. Convert to EUI-64 address. Complement Group bit. */
1656     ip_2_ip6(&netif->ip6_addr[0])->addr[2] = lwip_htonl((((u32_t)(netif->hwaddr[0] ^ 0x02)) << 24) |
1657         ((u32_t)(netif->hwaddr[1]) << 16) |
1658         ((u32_t)(netif->hwaddr[2]) << 8) |
1659         (0xff));
1660     ip_2_ip6(&netif->ip6_addr[0])->addr[3] = lwip_htonl((u32_t)(0xfeul << 24) |
1661         ((u32_t)(netif->hwaddr[3]) << 16) |
1662         ((u32_t)(netif->hwaddr[4]) << 8) |
1663         (netif->hwaddr[5]));
1664   } else {
1665     /* Use hwaddr directly as interface ID. */
1666     ip_2_ip6(&netif->ip6_addr[0])->addr[2] = 0;
1667     ip_2_ip6(&netif->ip6_addr[0])->addr[3] = 0;
1668 
1669     addr_index = 3;
1670     for (i = 0; (i < 8) && (i < netif->hwaddr_len); i++) {
1671       if (i == 4) {
1672         addr_index--;
1673       }
1674       ip_2_ip6(&netif->ip6_addr[0])->addr[addr_index] |= lwip_htonl(((u32_t)(netif->hwaddr[netif->hwaddr_len - i - 1])) << (8 * (i & 0x03)));
1675     }
1676   }
1677 
1678   /* Set a link-local zone. Even though the zone is implied by the owning
1679    * netif, setting the zone anyway has two important conceptual advantages:
1680    * 1) it avoids the need for a ton of exceptions in internal code, allowing
1681    *    e.g. ip6_addr_cmp() to be used on local addresses;
1682    * 2) the properly zoned address is visible externally, e.g. when any outside
1683    *    code enumerates available addresses or uses one to bind a socket.
1684    * Any external code unaware of address scoping is likely to just ignore the
1685    * zone field, so this should not create any compatibility problems. */
1686   ip6_addr_assign_zone(ip_2_ip6(&netif->ip6_addr[0]), IP6_UNICAST, netif);
1687 
1688   /* Set address state. */
1689 #if LWIP_IPV6_DUP_DETECT_ATTEMPTS
1690   /* Will perform duplicate address detection (DAD). */
1691   netif_ip6_addr_set_state(netif, 0, IP6_ADDR_TENTATIVE);
1692 #else
1693   /* Consider address valid. */
1694   netif_ip6_addr_set_state(netif, 0, IP6_ADDR_PREFERRED);
1695 #endif /* LWIP_IPV6_AUTOCONFIG */
1696 }
1697 
1698 /**
1699  * @ingroup netif_ip6
1700  * This function allows for the easy addition of a new IPv6 address to an interface.
1701  * It takes care of finding an empty slot and then sets the address tentative
1702  * (to make sure that all the subsequent processing happens).
1703  *
1704  * @param netif netif to add the address on
1705  * @param ip6addr address to add
1706  * @param chosen_idx if != NULL, the chosen IPv6 address index will be stored here
1707  */
1708 err_t
1709 netif_add_ip6_address(struct netif *netif, const ip6_addr_t *ip6addr, s8_t *chosen_idx)
1710 {
1711   s8_t i;
1712 
1713   LWIP_ASSERT_CORE_LOCKED();
1714 
1715   LWIP_ASSERT("netif_add_ip6_address: invalid netif", netif != NULL);
1716   LWIP_ASSERT("netif_add_ip6_address: invalid ip6addr", ip6addr != NULL);
1717 
1718   i = netif_get_ip6_addr_match(netif, ip6addr);
1719   if (i >= 0) {
1720     /* Address already added */
1721     if (chosen_idx != NULL) {
1722       *chosen_idx = i;
1723     }
1724     return ERR_OK;
1725   }
1726 
1727   /* Find a free slot. The first one is reserved for link-local addresses. */
1728   for (i = ip6_addr_islinklocal(ip6addr) ? 0 : 1; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
1729     if (ip6_addr_isinvalid(netif_ip6_addr_state(netif, i))) {
1730       ip_addr_copy_from_ip6(netif->ip6_addr[i], *ip6addr);
1731       ip6_addr_assign_zone(ip_2_ip6(&netif->ip6_addr[i]), IP6_UNICAST, netif);
1732       netif_ip6_addr_set_state(netif, i, IP6_ADDR_TENTATIVE);
1733       if (chosen_idx != NULL) {
1734         *chosen_idx = i;
1735       }
1736       return ERR_OK;
1737     }
1738   }
1739 
1740   if (chosen_idx != NULL) {
1741     *chosen_idx = -1;
1742   }
1743   return ERR_VAL;
1744 }
1745 
1746 /** Dummy IPv6 output function for netifs not supporting IPv6
1747  */
1748 static err_t
1749 netif_null_output_ip6(struct netif *netif, struct pbuf *p, const ip6_addr_t *ipaddr)
1750 {
1751   LWIP_UNUSED_ARG(netif);
1752   LWIP_UNUSED_ARG(p);
1753   LWIP_UNUSED_ARG(ipaddr);
1754 
1755   return ERR_IF;
1756 }
1757 #endif /* LWIP_IPV6 */
1758 
1759 #if LWIP_IPV4
1760 /** Dummy IPv4 output function for netifs not supporting IPv4
1761  */
1762 static err_t
1763 netif_null_output_ip4(struct netif *netif, struct pbuf *p, const ip4_addr_t *ipaddr)
1764 {
1765   LWIP_UNUSED_ARG(netif);
1766   LWIP_UNUSED_ARG(p);
1767   LWIP_UNUSED_ARG(ipaddr);
1768 
1769   return ERR_IF;
1770 }
1771 #endif /* LWIP_IPV4 */
1772 
1773 /**
1774 * @ingroup netif
1775 * Return the interface index for the netif with name
1776 * or NETIF_NO_INDEX if not found/on error
1777 *
1778 * @param name the name of the netif
1779 */
1780 u8_t
1781 netif_name_to_index(const char *name)
1782 {
1783   struct netif *netif = netif_find(name);
1784   if (netif != NULL) {
1785     return netif_get_index(netif);
1786   }
1787   /* No name found, return invalid index */
1788   return NETIF_NO_INDEX;
1789 }
1790 
1791 /**
1792 * @ingroup netif
1793 * Return the interface name for the netif matching index
1794 * or NULL if not found/on error
1795 *
1796 * @param idx the interface index of the netif
1797 * @param name char buffer of at least NETIF_NAMESIZE bytes
1798 */
1799 char *
1800 #ifdef LOSCFG_NET_CONTAINER
1801 netif_index_to_name(u8_t idx, char *name, struct net_group *group)
1802 #else
1803 netif_index_to_name(u8_t idx, char *name)
1804 #endif
1805 {
1806 #ifdef LOSCFG_NET_CONTAINER
1807   struct netif *netif = netif_get_by_index(idx, group);
1808 #else
1809   struct netif *netif = netif_get_by_index(idx);
1810 #endif
1811 
1812   if (netif != NULL) {
1813     name[0] = netif->name[0];
1814     name[1] = netif->name[1];
1815     lwip_itoa(&name[2], NETIF_NAMESIZE - 2, netif_index_to_num(idx));
1816     return name;
1817   }
1818   return NULL;
1819 }
1820 
1821 /**
1822 * @ingroup netif
1823 * Return the interface for the netif index
1824 *
1825 * @param idx index of netif to find
1826 */
1827 struct netif *
1828 #ifdef LOSCFG_NET_CONTAINER
1829 netif_get_by_index(u8_t idx, struct net_group *group)
1830 #else
1831 netif_get_by_index(u8_t idx)
1832 #endif
1833 {
1834   struct netif *netif;
1835 
1836   LWIP_ASSERT_CORE_LOCKED();
1837 
1838 #ifdef LOSCFG_NET_CONTAINER
1839   if (idx != NETIF_NO_INDEX && group != NULL) {
1840     NETIF_FOREACH(netif, group) {
1841 #else
1842   if (idx != NETIF_NO_INDEX) {
1843     NETIF_FOREACH(netif) {
1844 #endif
1845       if (idx == netif_get_index(netif)) {
1846         return netif; /* found! */
1847       }
1848     }
1849   }
1850 
1851   return NULL;
1852 }
1853 
1854 #ifndef netif_find
1855 /**
1856  * @ingroup netif
1857  * Find a network interface by searching for its name
1858  *
1859  * @param name the name of the netif (like netif->name) plus concatenated number
1860  * in ascii representation (e.g. 'en0')
1861  */
1862 struct netif *
1863 netif_find(const char *name)
1864 {
1865   struct netif *netif;
1866   u8_t num;
1867 
1868   LWIP_ASSERT_CORE_LOCKED();
1869 
1870   if (name == NULL) {
1871     return NULL;
1872   }
1873 
1874   num = (u8_t)atoi(&name[2]);
1875   if (!num && (name[2] != '0')) {
1876     /* this means atoi has failed */
1877     return NULL;
1878   }
1879 
1880   NETIF_FOREACH(netif) {
1881     if (num == netif->num &&
1882         name[0] == netif->name[0] &&
1883         name[1] == netif->name[1]) {
1884       LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: found %c%c\n", name[0], name[1]));
1885       return netif;
1886     }
1887   }
1888   LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: didn't find %c%c\n", name[0], name[1]));
1889   return NULL;
1890 }
1891 #endif
1892 
1893 #if LWIP_NETIF_EXT_STATUS_CALLBACK
1894 /**
1895  * @ingroup netif
1896  * Add extended netif events listener
1897  * @param callback pointer to listener structure
1898  * @param fn callback function
1899  */
1900 void
1901 netif_add_ext_callback(netif_ext_callback_t *callback, netif_ext_callback_fn fn)
1902 {
1903   LWIP_ASSERT_CORE_LOCKED();
1904   LWIP_ASSERT("callback must be != NULL", callback != NULL);
1905   LWIP_ASSERT("fn must be != NULL", fn != NULL);
1906 
1907   callback->callback_fn = fn;
1908   callback->next        = ext_callback;
1909   ext_callback          = callback;
1910 }
1911 
1912 /**
1913  * @ingroup netif
1914  * Remove extended netif events listener
1915  * @param callback pointer to listener structure
1916  */
1917 void
1918 netif_remove_ext_callback(netif_ext_callback_t* callback)
1919 {
1920   netif_ext_callback_t *last, *iter;
1921 
1922   LWIP_ASSERT_CORE_LOCKED();
1923   LWIP_ASSERT("callback must be != NULL", callback != NULL);
1924 
1925   if (ext_callback == NULL) {
1926     return;
1927   }
1928 
1929   if (callback == ext_callback) {
1930     ext_callback = ext_callback->next;
1931   } else {
1932     last = ext_callback;
1933     for (iter = ext_callback->next; iter != NULL; last = iter, iter = iter->next) {
1934       if (iter == callback) {
1935         LWIP_ASSERT("last != NULL", last != NULL);
1936         last->next = callback->next;
1937         callback->next = NULL;
1938         return;
1939       }
1940     }
1941   }
1942 }
1943 
1944 /**
1945  * Invoke extended netif status event
1946  * @param netif netif that is affected by change
1947  * @param reason change reason
1948  * @param args depends on reason, see reason description
1949  */
1950 void
1951 netif_invoke_ext_callback(struct netif *netif, netif_nsc_reason_t reason, const netif_ext_callback_args_t *args)
1952 {
1953   netif_ext_callback_t *callback = ext_callback;
1954 
1955   LWIP_ASSERT("netif must be != NULL", netif != NULL);
1956 
1957   while (callback != NULL) {
1958     callback->callback_fn(netif, reason, args);
1959     callback = callback->next;
1960   }
1961 }
1962 #endif /* LWIP_NETIF_EXT_STATUS_CALLBACK */
1963