3 * IGMP - Internet Group Management Protocol
8 * Copyright (c) 2002 CITEL Technologies Ltd.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
24 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * This file is a contribution to the lwIP TCP/IP stack.
36 * The Swedish Institute of Computer Science and Adam Dunkels
37 * are specifically granted permission to redistribute this
41 /*-------------------------------------------------------------
43 Although the rfc requires V1 AND V2 capability
44 we will only support v2 since now V1 is very old (August 1989)
45 V1 can be added if required
47 a debug print and statistic have been implemented to
49 -------------------------------------------------------------
50 -------------------------------------------------------------
52 A query for a specific group address (as opposed to ALLHOSTS)
53 has now been implemented as I am unsure if it is required
55 a debug print and statistic have been implemented to
57 -------------------------------------------------------------
58 -------------------------------------------------------------
60 The router alert rfc 2113 is implemented in outgoing packets
61 but not checked rigorously incoming
62 -------------------------------------------------------------
64 ------------------------------------------------------------*/
66 /*-----------------------------------------------------------------------------
67 * RFC 988 - Host extensions for IP multicasting - V0
68 * RFC 1054 - Host extensions for IP multicasting -
69 * RFC 1112 - Host extensions for IP multicasting - V1
70 * RFC 2236 - Internet Group Management Protocol, Version 2 - V2 <- this code is based on this RFC (it's the "de facto" standard)
71 * RFC 3376 - Internet Group Management Protocol, Version 3 - V3
72 * RFC 4604 - Using Internet Group Management Protocol Version 3... - V3+
73 * RFC 2113 - IP Router Alert Option -
74 *----------------------------------------------------------------------------*/
76 /*-----------------------------------------------------------------------------
78 *----------------------------------------------------------------------------*/
82 #if LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
84 #include "lwip/debug.h"
88 #include "lwip/inet.h"
89 #include "lwip/netif.h"
90 #include "lwip/icmp.h"
93 #include "lwip/stats.h"
94 #include "lwip/igmp.h"
98 /*-----------------------------------------------------------------------------
100 *----------------------------------------------------------------------------*/
102 static struct igmp_group* igmp_group_list;
103 static struct ip_addr allsystems;
104 static struct ip_addr allrouters;
107 * Initialize the IGMP module
112 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
114 IP4_ADDR(&allsystems, 224, 0, 0, 1);
115 IP4_ADDR(&allrouters, 224, 0, 0, 2);
120 * Dump global IGMP groups list
123 igmp_dump_group_list()
125 struct igmp_group *group = igmp_group_list;
127 while (group != NULL) {
128 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_dump_group_list: [%"U32_F"] ", (u32_t)(group->group_state)));
129 ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
130 LWIP_DEBUGF(IGMP_DEBUG, (" on if %x\n", (int) group->interface));
133 LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
136 #define igmp_dump_group_list()
137 #endif /* LWIP_DEBUG */
140 * Start IGMP processing on interface
142 * @param netif network interface on which start IGMP processing
145 igmp_start(struct netif *netif)
147 struct igmp_group* group;
149 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %x\n", (int) netif));
151 group = igmp_lookup_group(netif, &allsystems);
154 group->group_state = IGMP_GROUP_IDLE_MEMBER;
157 /* Allow the igmp messages at the MAC level */
158 if (netif->igmp_mac_filter != NULL) {
159 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
160 ip_addr_debug_print(IGMP_DEBUG, &allsystems);
161 LWIP_DEBUGF(IGMP_DEBUG, (") on if %x\n", (int) netif));
162 netif->igmp_mac_filter( netif, &allsystems, IGMP_ADD_MAC_FILTER);
172 * Stop IGMP processing on interface
174 * @param netif network interface on which stop IGMP processing
177 igmp_stop(struct netif *netif)
179 struct igmp_group *group = igmp_group_list;
180 struct igmp_group *prev = NULL;
181 struct igmp_group *next;
183 /* look for groups joined on this interface further down the list */
184 while (group != NULL) {
186 /* is it a group joined on this interface? */
187 if (group->interface == netif) {
188 /* is it the first group of the list? */
189 if (group == igmp_group_list) {
190 igmp_group_list = next;
192 /* is there a "previous" group defined? */
196 /* disable the group at the MAC level */
197 if (netif->igmp_mac_filter != NULL) {
198 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
199 ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
200 LWIP_DEBUGF(IGMP_DEBUG, (") on if %x\n", (int) netif));
201 netif->igmp_mac_filter(netif, &(group->group_address), IGMP_DEL_MAC_FILTER);
204 memp_free(MEMP_IGMP_GROUP, group);
206 /* change the "previous" */
216 * Report IGMP memberships for this interface
218 * @param netif network interface on which report IGMP memberships
221 igmp_report_groups( struct netif *netif)
223 struct igmp_group *group = igmp_group_list;
225 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %x\n", (int) netif));
227 while (group != NULL) {
228 if (group->interface == netif) {
229 igmp_delaying_member( group, IGMP_JOIN_DELAYING_MEMBER_TMR);
236 * Search for a group in the global igmp_group_list
238 * @param ifp the network interface for which to look
239 * @param addr the group ip address to search for
240 * @return a struct igmp_group* if the group has been found,
241 * NULL if the group wasn't found.
244 igmp_lookfor_group(struct netif *ifp, struct ip_addr *addr)
246 struct igmp_group *group = igmp_group_list;
248 while (group != NULL) {
249 if ((group->interface == ifp) && (ip_addr_cmp(&(group->group_address), addr))) {
255 /* to be clearer, we return NULL here instead of
256 * 'group' (which is also NULL at this point).
262 * Search for a specific igmp group and create a new one if not found-
264 * @param ifp the network interface for which to look
265 * @param addr the group ip address to search
266 * @return a struct igmp_group*,
267 * NULL on memory error.
270 igmp_lookup_group(struct netif *ifp, struct ip_addr *addr)
272 struct igmp_group *group = igmp_group_list;
274 /* Search if the group already exists */
275 group = igmp_lookfor_group(ifp, addr);
277 /* Group already exists. */
281 /* Group doesn't exist yet, create a new one */
282 group = memp_malloc(MEMP_IGMP_GROUP);
284 group->interface = ifp;
285 ip_addr_set(&(group->group_address), addr);
286 group->timer = 0; /* Not running */
287 group->group_state = IGMP_GROUP_NON_MEMBER;
288 group->last_reporter_flag = 0;
290 group->next = igmp_group_list;
292 igmp_group_list = group;
295 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group?"":"impossible to ")));
296 ip_addr_debug_print(IGMP_DEBUG, addr);
297 LWIP_DEBUGF(IGMP_DEBUG, (" on if %x\n", (int) ifp));
303 * Remove a group in the global igmp_group_list
305 * @param group the group to remove from the global igmp_group_list
306 * @return ERR_OK if group was removed from the list, an err_t otherwise
309 igmp_remove_group(struct igmp_group *group)
313 /* Is it the first group? */
314 if (igmp_group_list == group) {
315 igmp_group_list = group->next;
317 /* look for group further down the list */
318 struct igmp_group *tmpGroup;
319 for (tmpGroup = igmp_group_list; tmpGroup != NULL; tmpGroup = tmpGroup->next) {
320 if (tmpGroup->next == group) {
321 tmpGroup->next = group->next;
325 /* Group not found in the global igmp_group_list */
326 if (tmpGroup == NULL)
330 memp_free(MEMP_IGMP_GROUP, group);
336 * Called from ip_input() if a new IGMP packet is received.
338 * @param p received igmp packet, p->payload pointing to the ip header
339 * @param inp network interface on which the packet was received
340 * @param dest destination ip address of the igmp packet
343 igmp_input(struct pbuf *p, struct netif *inp, struct ip_addr *dest)
345 struct ip_hdr * iphdr;
346 struct igmp_msg* igmp;
347 struct igmp_group* group;
348 struct igmp_group* groupref;
350 /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */
352 if (pbuf_header(p, -(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
354 IGMP_STATS_INC(igmp.lenerr);
355 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
359 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
360 ip_addr_debug_print(IGMP_DEBUG, &(iphdr->src));
361 LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
362 ip_addr_debug_print(IGMP_DEBUG, &(iphdr->dest));
363 LWIP_DEBUGF(IGMP_DEBUG, (" on if %x\n", (int) inp));
365 /* Now calculate and check the checksum */
366 igmp = (struct igmp_msg *)p->payload;
367 if (inet_chksum(igmp, p->len)) {
369 IGMP_STATS_INC(igmp.chkerr);
370 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
374 /* Packet is ok so find an existing group */
375 group = igmp_lookfor_group(inp, dest); /* use the incoming IP address! */
377 /* If group can be found or create... */
380 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
384 /* NOW ACT ON THE INCOMING MESSAGE TYPE... */
385 switch (igmp->igmp_msgtype) {
386 case IGMP_MEMB_QUERY: {
387 /* IGMP_MEMB_QUERY to the "all systems" address ? */
388 if ((ip_addr_cmp(dest, &allsystems)) && (igmp->igmp_group_address.addr == 0)) {
389 /* THIS IS THE GENERAL QUERY */
390 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: General IGMP_MEMB_QUERY on \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
392 if (igmp->igmp_maxresp == 0) {
393 IGMP_STATS_INC(igmp.v1_rxed);
394 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
395 igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
398 IGMP_STATS_INC(igmp.group_query_rxed);
399 groupref = igmp_group_list;
401 /* Do not send messages on the all systems group address! */
402 if ((groupref->interface == inp) && (!(ip_addr_cmp(&(groupref->group_address), &allsystems)))) {
403 igmp_delaying_member( groupref, igmp->igmp_maxresp);
405 groupref = groupref->next;
408 /* IGMP_MEMB_QUERY to a specific group ? */
409 if (group->group_address.addr != 0) {
410 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
411 ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
412 if (ip_addr_cmp (dest, &allsystems)) {
413 LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
414 /* we first need to re-lookfor the group since we used dest last time */
415 group = igmp_lookfor_group(inp, &igmp->igmp_group_address);
417 LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
421 IGMP_STATS_INC(igmp.unicast_query);
422 igmp_delaying_member( group, igmp->igmp_maxresp);
428 case IGMP_V2_MEMB_REPORT: {
429 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
431 IGMP_STATS_INC(igmp.report_rxed);
432 if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
433 /* This is on a specific group we have already looked up */
434 group->timer = 0; /* stopped */
435 group->group_state = IGMP_GROUP_IDLE_MEMBER;
436 group->last_reporter_flag = 0;
441 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %x in state %x on group %x on if %x\n", (int) igmp->igmp_msgtype, (int) group->group_state, (int) &group, (int) group->interface));
451 * Join a group on one network interface.
453 * @param ifaddr ip address of the network interface which should join a new group
454 * @param groupaddr the ip address of the group which to join
455 * @return ERR_OK if group was joined on the netif(s), an err_t otherwise
458 igmp_joingroup(struct ip_addr *ifaddr, struct ip_addr *groupaddr)
460 err_t err = ERR_VAL; /* no matching interface */
461 struct igmp_group *group;
464 /* make sure it is multicast address */
465 LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
466 LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
468 /* loop through netif's */
470 while (netif != NULL) {
471 /* Should we join this interface ? */
472 if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
473 /* find group or create a new one if not found */
474 group = igmp_lookup_group(netif, groupaddr);
477 /* This should create a new group, check the state to make sure */
478 if (group->group_state != IGMP_GROUP_NON_MEMBER) {
479 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
481 /* OK - it was new group */
482 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to new group: "));
483 ip_addr_debug_print(IGMP_DEBUG, groupaddr);
484 LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
486 /* If first use of the group, allow the group at the MAC level */
487 if ((group->use==0) && (netif->igmp_mac_filter != NULL)) {
488 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: igmp_mac_filter(ADD "));
489 ip_addr_debug_print(IGMP_DEBUG, groupaddr);
490 LWIP_DEBUGF(IGMP_DEBUG, (") on if %x\n", (int) netif));
491 netif->igmp_mac_filter(netif, groupaddr, IGMP_ADD_MAC_FILTER);
494 IGMP_STATS_INC(igmp.join_sent);
495 igmp_send(group, IGMP_V2_MEMB_REPORT);
497 igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
499 /* Need to work out where this timer comes from */
500 group->group_state = IGMP_GROUP_DELAYING_MEMBER;
502 /* Increment group use */
504 /* Join on this interface */
507 /* Return an error even if some network interfaces are joined */
508 /** @todo undo any other netif already joined */
509 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: Not enought memory to join to group\n"));
513 /* proceed to next network interface */
521 * Leave a group on one network interface.
523 * @param ifaddr ip address of the network interface which should leave a group
524 * @param groupaddr the ip address of the group which to leave
525 * @return ERR_OK if group was left on the netif(s), an err_t otherwise
528 igmp_leavegroup(struct ip_addr *ifaddr, struct ip_addr *groupaddr)
530 err_t err = ERR_VAL; /* no matching interface */
531 struct igmp_group *group;
534 /* make sure it is multicast address */
535 LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
536 LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
538 /* loop through netif's */
540 while (netif != NULL) {
541 /* Should we leave this interface ? */
542 if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
544 group = igmp_lookfor_group(netif, groupaddr);
547 /* Only send a leave if the flag is set according to the state diagram */
548 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: Leaving group: "));
549 ip_addr_debug_print(IGMP_DEBUG, groupaddr);
550 LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
552 /* If there is no other use of the group */
553 if (group->use <= 1) {
554 /* If we are the last reporter for this group */
555 if (group->last_reporter_flag) {
556 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: sending leaving group\n"));
557 IGMP_STATS_INC(igmp.leave_sent);
558 igmp_send(group, IGMP_LEAVE_GROUP);
561 /* Disable the group at the MAC level */
562 if (netif->igmp_mac_filter != NULL) {
563 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: igmp_mac_filter(DEL "));
564 ip_addr_debug_print(IGMP_DEBUG, groupaddr);
565 LWIP_DEBUGF(IGMP_DEBUG, (") on if %x\n", (int) netif));
566 netif->igmp_mac_filter(netif, groupaddr, IGMP_DEL_MAC_FILTER);
569 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: remove group: "));
570 ip_addr_debug_print(IGMP_DEBUG, groupaddr);
571 LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
574 igmp_remove_group(group);
576 /* Decrement group use */
579 /* Leave on this interface */
582 /* It's not a fatal error on "leavegroup" */
583 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: not member of group\n"));
586 /* proceed to next network interface */
594 * The igmp timer function (both for NO_SYS=1 and =0)
595 * Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
600 struct igmp_group *group = igmp_group_list;
602 while (group != NULL) {
603 if (group->timer != 0) {
605 if (group->timer == 0) {
614 * Called if a timeout for one group is reached.
615 * Sends a report for this group.
617 * @param group an igmp_group for which a timeout is reached
620 igmp_timeout(struct igmp_group *group)
622 /* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group */
623 if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
624 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
625 ip_addr_debug_print(IGMP_DEBUG, &(group->group_address));
626 LWIP_DEBUGF(IGMP_DEBUG, (" on if %x\n", (int) group->interface));
628 igmp_send(group, IGMP_V2_MEMB_REPORT);
633 * Start a timer for an igmp group
635 * @param group the igmp_group for which to start a timer
636 * @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
637 * every call to igmp_tmr())
640 igmp_start_timer(struct igmp_group *group, u8_t max_time)
643 * @todo Important !! this should be random 0 -> max_time. Find out how to do this
645 group->timer = max_time;
649 * Stop a timer for an igmp_group
651 * @param group the igmp_group for which to stop the timer
654 igmp_stop_timer(struct igmp_group *group)
660 * Delaying membership report for a group if necessary
662 * @param group the igmp_group for which "delaying" membership report
663 * @param maxresp query delay
666 igmp_delaying_member( struct igmp_group *group, u8_t maxresp)
668 if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) || ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) && (maxresp > group->timer))) {
669 igmp_start_timer(group, (maxresp)/2);
670 group->group_state = IGMP_GROUP_DELAYING_MEMBER;
676 * Sends an IP packet on a network interface. This function constructs the IP header
677 * and calculates the IP header checksum. If the source IP address is NULL,
678 * the IP address of the outgoing network interface is filled in as source address.
680 * @param p the packet to send (p->payload points to the data, e.g. next
681 protocol header; if dest == IP_HDRINCL, p already includes an IP
682 header and p->payload points to that IP header)
683 * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
684 * IP address of the netif used to send is used as source address)
685 * @param dest the destination IP address to send the packet to
686 * @param ttl the TTL value to be set in the IP header
687 * @param proto the PROTOCOL to be set in the IP header
688 * @param netif the netif on which to send this packet
689 * @return ERR_OK if the packet was sent OK
690 * ERR_BUF if p doesn't have enough space for IP/LINK headers
691 * returns errors returned by netif->output
694 igmp_ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
695 u8_t ttl, u8_t proto, struct netif *netif)
697 static u16_t ip_id = 0;
698 struct ip_hdr * iphdr = NULL;
701 /* First write in the "router alert" */
702 if (pbuf_header(p, ROUTER_ALERTLEN)) {
703 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_ip_output_if: not enough room for IP header in pbuf\n"));
707 /* This is the "router alert" option */
709 ra[0] = htons (0x9404);
712 /* now the normal ip header */
713 if (pbuf_header(p, IP_HLEN)) {
714 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_ip_output_if: not enough room for IP header in pbuf\n"));
719 if (dest != IP_HDRINCL) {
720 iphdr->_ttl_proto = (proto<<8);
721 iphdr->_ttl_proto |= ttl;
723 /* iphdr->dest = dest->addr; */
724 ip_addr_set(&(iphdr->dest), dest);
725 #ifdef HAVE_BITFIELDS
726 iphdr->_v_hl_tos |= ((IP_HLEN+ ROUTER_ALERTLEN)/4)<<16;
727 iphdr->_v_hl_tos |= 4<<24;
729 iphdr->_v_hl_tos = (4 << 4) | ((IP_HLEN + ROUTER_ALERTLEN)/ 4 & 0xf);
730 #endif /* HAVE_BITFIELDS */
732 iphdr->_v_hl_tos |= 0;
733 iphdr->_len = htons(p->tot_len);
734 iphdr->_offset = htons(0);
735 iphdr->_id = htons(ip_id++);
737 if (ip_addr_isany(src)) {
738 ip_addr_set(&(iphdr->src), &(netif->ip_addr));
740 ip_addr_set(&(iphdr->src), src);
744 iphdr->_chksum = inet_chksum(iphdr, IP_HLEN + ROUTER_ALERTLEN);
746 dest = &(iphdr->dest);
753 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_ip_output_if: sending to if %x\n", (int) netif));
755 return netif->output(netif, p, dest);
759 * Send an igmp packet to a specific group.
761 * @param group the group to which to send the packet
762 * @param type the type of igmp packet to send
765 igmp_send(struct igmp_group *group, u8_t type)
767 struct pbuf* p = NULL;
768 struct igmp_msg* igmp = NULL;
769 struct ip_addr src = {0};
770 struct ip_addr* dest = NULL;
772 /* IP header + IGMP header */
773 p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
777 LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
778 (p->len >= sizeof(struct igmp_msg)));
779 ip_addr_set(&src, &((group->interface)->ip_addr));
781 if (type == IGMP_V2_MEMB_REPORT) {
782 dest = &(group->group_address);
783 IGMP_STATS_INC(igmp.report_sent);
784 ip_addr_set(&(igmp->igmp_group_address), &(group->group_address));
785 group->last_reporter_flag = 1; /* Remember we were the last to report */
787 if (type == IGMP_LEAVE_GROUP) {
789 ip_addr_set(&(igmp->igmp_group_address), &(group->group_address));
793 if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
794 igmp->igmp_msgtype = type;
795 igmp->igmp_maxresp = 0;
796 igmp->igmp_checksum = 0;
797 igmp->igmp_checksum = inet_chksum( igmp, IGMP_MINLEN);
799 igmp_ip_output_if( p, &src, dest, IGMP_TTL, IP_PROTO_IGMP, group->interface);
804 LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
808 #endif /* LWIP_IGMP */