1 | /**
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2 | * @file
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3 | * IGMP - Internet Group Management Protocol
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4 | *
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5 | * @defgroup igmp IGMP
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6 | * @ingroup ip4
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7 | * To be called from TCPIP thread
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8 | */
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9 |
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10 | /*
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11 | * Copyright (c) 2002 CITEL Technologies Ltd.
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12 | * All rights reserved.
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13 | *
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14 | * Redistribution and use in source and binary forms, with or without
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15 | * modification, are permitted provided that the following conditions
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16 | * are met:
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17 | * 1. Redistributions of source code must retain the above copyright
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18 | * notice, this list of conditions and the following disclaimer.
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19 | * 2. Redistributions in binary form must reproduce the above copyright
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20 | * notice, this list of conditions and the following disclaimer in the
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21 | * documentation and/or other materials provided with the distribution.
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22 | * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors
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23 | * may be used to endorse or promote products derived from this software
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24 | * without specific prior written permission.
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25 | *
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26 | * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
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27 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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28 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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29 | * ARE DISCLAIMED. IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE
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30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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31 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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32 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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33 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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34 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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35 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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36 | * SUCH DAMAGE.
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37 | *
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38 | * This file is a contribution to the lwIP TCP/IP stack.
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39 | * The Swedish Institute of Computer Science and Adam Dunkels
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40 | * are specifically granted permission to redistribute this
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41 | * source code.
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42 | */
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43 |
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44 | /*-------------------------------------------------------------
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45 | Note 1)
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46 | Although the rfc requires V1 AND V2 capability
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47 | we will only support v2 since now V1 is very old (August 1989)
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48 | V1 can be added if required
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49 |
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50 | a debug print and statistic have been implemented to
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51 | show this up.
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52 | -------------------------------------------------------------
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53 | -------------------------------------------------------------
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54 | Note 2)
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55 | A query for a specific group address (as opposed to ALLHOSTS)
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56 | has now been implemented as I am unsure if it is required
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57 |
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58 | a debug print and statistic have been implemented to
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59 | show this up.
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60 | -------------------------------------------------------------
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61 | -------------------------------------------------------------
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62 | Note 3)
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63 | The router alert rfc 2113 is implemented in outgoing packets
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64 | but not checked rigorously incoming
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65 | -------------------------------------------------------------
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66 | Steve Reynolds
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67 | ------------------------------------------------------------*/
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68 |
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69 | /*-----------------------------------------------------------------------------
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70 | * RFC 988 - Host extensions for IP multicasting - V0
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71 | * RFC 1054 - Host extensions for IP multicasting -
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72 | * RFC 1112 - Host extensions for IP multicasting - V1
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73 | * RFC 2236 - Internet Group Management Protocol, Version 2 - V2 <- this code is based on this RFC (it's the "de facto" standard)
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74 | * RFC 3376 - Internet Group Management Protocol, Version 3 - V3
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75 | * RFC 4604 - Using Internet Group Management Protocol Version 3... - V3+
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76 | * RFC 2113 - IP Router Alert Option -
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77 | *----------------------------------------------------------------------------*/
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78 |
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79 | /*-----------------------------------------------------------------------------
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80 | * Includes
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81 | *----------------------------------------------------------------------------*/
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82 |
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83 | #include "lwip/opt.h"
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84 |
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85 | #if LWIP_IPV4 && LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
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86 |
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87 | #include "lwip/igmp.h"
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88 | #include "lwip/debug.h"
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89 | #include "lwip/def.h"
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90 | #include "lwip/mem.h"
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91 | #include "lwip/ip.h"
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92 | #include "lwip/inet_chksum.h"
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93 | #include "lwip/netif.h"
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94 | #include "lwip/stats.h"
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95 | #include "lwip/prot/igmp.h"
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96 |
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97 | #include <string.h>
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98 |
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99 | static struct igmp_group *igmp_lookup_group(struct netif *ifp, const ip4_addr_t *addr);
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100 | static err_t igmp_remove_group(struct netif *netif, struct igmp_group *group);
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101 | static void igmp_timeout(struct netif *netif, struct igmp_group *group);
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102 | static void igmp_start_timer(struct igmp_group *group, u8_t max_time);
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103 | static void igmp_delaying_member(struct igmp_group *group, u8_t maxresp);
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104 | static err_t igmp_ip_output_if(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest, struct netif *netif);
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105 | static void igmp_send(struct netif *netif, struct igmp_group *group, u8_t type);
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106 |
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107 | static ip4_addr_t allsystems;
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108 | static ip4_addr_t allrouters;
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109 |
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110 | /**
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111 | * Initialize the IGMP module
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112 | */
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113 | void
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114 | igmp_init(void)
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115 | {
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116 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
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117 |
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118 | IP4_ADDR(&allsystems, 224, 0, 0, 1);
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119 | IP4_ADDR(&allrouters, 224, 0, 0, 2);
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120 | }
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121 |
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122 | /**
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123 | * Start IGMP processing on interface
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124 | *
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125 | * @param netif network interface on which start IGMP processing
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126 | */
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127 | err_t
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128 | igmp_start(struct netif *netif)
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129 | {
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130 | struct igmp_group *group;
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131 |
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132 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %p\n", (void *)netif));
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133 |
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134 | group = igmp_lookup_group(netif, &allsystems);
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135 |
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136 | if (group != NULL) {
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137 | group->group_state = IGMP_GROUP_IDLE_MEMBER;
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138 | group->use++;
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139 |
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140 | /* Allow the igmp messages at the MAC level */
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141 | if (netif->igmp_mac_filter != NULL) {
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142 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
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143 | ip4_addr_debug_print_val(IGMP_DEBUG, allsystems);
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144 | LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void *)netif));
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145 | netif->igmp_mac_filter(netif, &allsystems, NETIF_ADD_MAC_FILTER);
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146 | }
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147 |
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148 | return ERR_OK;
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149 | }
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150 |
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151 | return ERR_MEM;
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152 | }
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153 |
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154 | /**
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155 | * Stop IGMP processing on interface
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156 | *
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157 | * @param netif network interface on which stop IGMP processing
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158 | */
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159 | err_t
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160 | igmp_stop(struct netif *netif)
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161 | {
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162 | struct igmp_group *group = netif_igmp_data(netif);
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163 |
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164 | netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_IGMP, NULL);
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165 |
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166 | while (group != NULL) {
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167 | struct igmp_group *next = group->next; /* avoid use-after-free below */
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168 |
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169 | /* disable the group at the MAC level */
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170 | if (netif->igmp_mac_filter != NULL) {
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171 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
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172 | ip4_addr_debug_print_val(IGMP_DEBUG, group->group_address);
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173 | LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void *)netif));
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174 | netif->igmp_mac_filter(netif, &(group->group_address), NETIF_DEL_MAC_FILTER);
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175 | }
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176 |
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177 | /* free group */
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178 | memp_free(MEMP_IGMP_GROUP, group);
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179 |
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180 | /* move to "next" */
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181 | group = next;
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182 | }
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183 | return ERR_OK;
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184 | }
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185 |
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186 | /**
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187 | * Report IGMP memberships for this interface
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188 | *
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189 | * @param netif network interface on which report IGMP memberships
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190 | */
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191 | void
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192 | igmp_report_groups(struct netif *netif)
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193 | {
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194 | struct igmp_group *group = netif_igmp_data(netif);
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195 |
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196 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %p\n", (void *)netif));
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197 |
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198 | /* Skip the first group in the list, it is always the allsystems group added in igmp_start() */
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199 | if (group != NULL) {
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200 | group = group->next;
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201 | }
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202 |
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203 | while (group != NULL) {
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204 | igmp_delaying_member(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
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205 | group = group->next;
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206 | }
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207 | }
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208 |
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209 | /**
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210 | * Search for a group in the netif's igmp group list
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211 | *
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212 | * @param ifp the network interface for which to look
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213 | * @param addr the group ip address to search for
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214 | * @return a struct igmp_group* if the group has been found,
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215 | * NULL if the group wasn't found.
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216 | */
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217 | struct igmp_group *
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218 | igmp_lookfor_group(struct netif *ifp, const ip4_addr_t *addr)
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219 | {
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220 | struct igmp_group *group = netif_igmp_data(ifp);
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221 |
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222 | while (group != NULL) {
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223 | if (ip4_addr_cmp(&(group->group_address), addr)) {
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224 | return group;
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225 | }
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226 | group = group->next;
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227 | }
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228 |
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229 | /* to be clearer, we return NULL here instead of
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230 | * 'group' (which is also NULL at this point).
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231 | */
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232 | return NULL;
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233 | }
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234 |
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235 | /**
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236 | * Search for a specific igmp group and create a new one if not found-
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237 | *
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238 | * @param ifp the network interface for which to look
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239 | * @param addr the group ip address to search
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240 | * @return a struct igmp_group*,
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241 | * NULL on memory error.
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242 | */
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243 | static struct igmp_group *
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244 | igmp_lookup_group(struct netif *ifp, const ip4_addr_t *addr)
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245 | {
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246 | struct igmp_group *group;
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247 | struct igmp_group *list_head = netif_igmp_data(ifp);
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248 |
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249 | /* Search if the group already exists */
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250 | group = igmp_lookfor_group(ifp, addr);
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251 | if (group != NULL) {
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252 | /* Group already exists. */
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253 | return group;
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254 | }
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255 |
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256 | /* Group doesn't exist yet, create a new one */
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257 | group = (struct igmp_group *)memp_malloc(MEMP_IGMP_GROUP);
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258 | if (group != NULL) {
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259 | ip4_addr_set(&(group->group_address), addr);
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260 | group->timer = 0; /* Not running */
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261 | group->group_state = IGMP_GROUP_NON_MEMBER;
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262 | group->last_reporter_flag = 0;
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263 | group->use = 0;
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264 |
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265 | /* Ensure allsystems group is always first in list */
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266 | if (list_head == NULL) {
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267 | /* this is the first entry in linked list */
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268 | LWIP_ASSERT("igmp_lookup_group: first group must be allsystems",
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269 | (ip4_addr_cmp(addr, &allsystems) != 0));
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270 | group->next = NULL;
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271 | netif_set_client_data(ifp, LWIP_NETIF_CLIENT_DATA_INDEX_IGMP, group);
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272 | } else {
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273 | /* append _after_ first entry */
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274 | LWIP_ASSERT("igmp_lookup_group: all except first group must not be allsystems",
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275 | (ip4_addr_cmp(addr, &allsystems) == 0));
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276 | group->next = list_head->next;
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277 | list_head->next = group;
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278 | }
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279 | }
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280 |
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281 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group ? "" : "impossible to ")));
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282 | ip4_addr_debug_print(IGMP_DEBUG, addr);
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283 | LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void *)ifp));
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284 |
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285 | return group;
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286 | }
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287 |
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288 | /**
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289 | * Remove a group from netif's igmp group list, but don't free it yet
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290 | *
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291 | * @param group the group to remove from the netif's igmp group list
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292 | * @return ERR_OK if group was removed from the list, an err_t otherwise
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293 | */
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294 | static err_t
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295 | igmp_remove_group(struct netif *netif, struct igmp_group *group)
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296 | {
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297 | err_t err = ERR_OK;
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298 | struct igmp_group *tmp_group;
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299 |
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300 | /* Skip the first group in the list, it is always the allsystems group added in igmp_start() */
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301 | for (tmp_group = netif_igmp_data(netif); tmp_group != NULL; tmp_group = tmp_group->next) {
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302 | if (tmp_group->next == group) {
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303 | tmp_group->next = group->next;
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304 | break;
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305 | }
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306 | }
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307 | /* Group not found in netif's igmp group list */
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308 | if (tmp_group == NULL) {
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309 | err = ERR_ARG;
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310 | }
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311 |
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312 | return err;
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313 | }
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314 |
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315 | /**
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316 | * Called from ip_input() if a new IGMP packet is received.
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317 | *
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318 | * @param p received igmp packet, p->payload pointing to the igmp header
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319 | * @param inp network interface on which the packet was received
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320 | * @param dest destination ip address of the igmp packet
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321 | */
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322 | void
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323 | igmp_input(struct pbuf *p, struct netif *inp, const ip4_addr_t *dest)
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324 | {
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325 | struct igmp_msg *igmp;
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326 | struct igmp_group *group;
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327 | struct igmp_group *groupref;
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328 |
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329 | IGMP_STATS_INC(igmp.recv);
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330 |
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331 | /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */
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332 | if (p->len < IGMP_MINLEN) {
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333 | pbuf_free(p);
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334 | IGMP_STATS_INC(igmp.lenerr);
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335 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
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336 | return;
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337 | }
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338 |
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339 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
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340 | ip4_addr_debug_print_val(IGMP_DEBUG, ip4_current_header()->src);
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341 | LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
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342 | ip4_addr_debug_print_val(IGMP_DEBUG, ip4_current_header()->dest);
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343 | LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void *)inp));
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344 |
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345 | /* Now calculate and check the checksum */
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346 | igmp = (struct igmp_msg *)p->payload;
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347 | if (inet_chksum(igmp, p->len)) {
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348 | pbuf_free(p);
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349 | IGMP_STATS_INC(igmp.chkerr);
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350 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
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351 | return;
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352 | }
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353 |
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354 | /* Packet is ok so find an existing group */
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355 | group = igmp_lookfor_group(inp, dest); /* use the destination IP address of incoming packet */
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356 |
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357 | /* If group can be found or create... */
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358 | if (!group) {
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359 | pbuf_free(p);
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360 | IGMP_STATS_INC(igmp.drop);
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361 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
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362 | return;
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363 | }
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364 |
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365 | /* NOW ACT ON THE INCOMING MESSAGE TYPE... */
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366 | switch (igmp->igmp_msgtype) {
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367 | case IGMP_MEMB_QUERY:
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368 | /* IGMP_MEMB_QUERY to the "all systems" address ? */
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369 | if ((ip4_addr_cmp(dest, &allsystems)) && ip4_addr_isany(&igmp->igmp_group_address)) {
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370 | /* THIS IS THE GENERAL QUERY */
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371 | 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)));
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372 |
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373 | if (igmp->igmp_maxresp == 0) {
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374 | IGMP_STATS_INC(igmp.rx_v1);
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375 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
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376 | igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
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377 | } else {
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378 | IGMP_STATS_INC(igmp.rx_general);
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379 | }
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380 |
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381 | groupref = netif_igmp_data(inp);
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382 |
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383 | /* Do not send messages on the all systems group address! */
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384 | /* Skip the first group in the list, it is always the allsystems group added in igmp_start() */
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385 | if (groupref != NULL) {
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386 | groupref = groupref->next;
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387 | }
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388 |
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389 | while (groupref) {
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390 | igmp_delaying_member(groupref, igmp->igmp_maxresp);
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391 | groupref = groupref->next;
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392 | }
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393 | } else {
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394 | /* IGMP_MEMB_QUERY to a specific group ? */
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395 | if (!ip4_addr_isany(&igmp->igmp_group_address)) {
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396 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
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397 | ip4_addr_debug_print_val(IGMP_DEBUG, igmp->igmp_group_address);
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398 | if (ip4_addr_cmp(dest, &allsystems)) {
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399 | ip4_addr_t groupaddr;
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400 | LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
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401 | /* we first need to re-look for the group since we used dest last time */
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402 | ip4_addr_copy(groupaddr, igmp->igmp_group_address);
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403 | group = igmp_lookfor_group(inp, &groupaddr);
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404 | } else {
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405 | LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
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406 | }
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407 |
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408 | if (group != NULL) {
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409 | IGMP_STATS_INC(igmp.rx_group);
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410 | igmp_delaying_member(group, igmp->igmp_maxresp);
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411 | } else {
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412 | IGMP_STATS_INC(igmp.drop);
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413 | }
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414 | } else {
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415 | IGMP_STATS_INC(igmp.proterr);
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416 | }
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417 | }
|
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418 | break;
|
---|
419 | case IGMP_V2_MEMB_REPORT:
|
---|
420 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
|
---|
421 | IGMP_STATS_INC(igmp.rx_report);
|
---|
422 | if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
|
---|
423 | /* This is on a specific group we have already looked up */
|
---|
424 | group->timer = 0; /* stopped */
|
---|
425 | group->group_state = IGMP_GROUP_IDLE_MEMBER;
|
---|
426 | group->last_reporter_flag = 0;
|
---|
427 | }
|
---|
428 | break;
|
---|
429 | default:
|
---|
430 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %d in state %d on group %p on if %p\n",
|
---|
431 | igmp->igmp_msgtype, group->group_state, (void *)&group, (void *)inp));
|
---|
432 | IGMP_STATS_INC(igmp.proterr);
|
---|
433 | break;
|
---|
434 | }
|
---|
435 |
|
---|
436 | pbuf_free(p);
|
---|
437 | return;
|
---|
438 | }
|
---|
439 |
|
---|
440 | /**
|
---|
441 | * @ingroup igmp
|
---|
442 | * Join a group on one network interface.
|
---|
443 | *
|
---|
444 | * @param ifaddr ip address of the network interface which should join a new group
|
---|
445 | * @param groupaddr the ip address of the group which to join
|
---|
446 | * @return ERR_OK if group was joined on the netif(s), an err_t otherwise
|
---|
447 | */
|
---|
448 | err_t
|
---|
449 | igmp_joingroup(const ip4_addr_t *ifaddr, const ip4_addr_t *groupaddr)
|
---|
450 | {
|
---|
451 | err_t err = ERR_VAL; /* no matching interface */
|
---|
452 | struct netif *netif;
|
---|
453 |
|
---|
454 | LWIP_ASSERT_CORE_LOCKED();
|
---|
455 |
|
---|
456 | /* make sure it is multicast address */
|
---|
457 | LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
|
---|
458 | LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
|
---|
459 |
|
---|
460 | /* loop through netif's */
|
---|
461 | NETIF_FOREACH(netif) {
|
---|
462 | /* Should we join this interface ? */
|
---|
463 | if ((netif->flags & NETIF_FLAG_IGMP) && ((ip4_addr_isany(ifaddr) || ip4_addr_cmp(netif_ip4_addr(netif), ifaddr)))) {
|
---|
464 | err = igmp_joingroup_netif(netif, groupaddr);
|
---|
465 | if (err != ERR_OK) {
|
---|
466 | /* Return an error even if some network interfaces are joined */
|
---|
467 | /** @todo undo any other netif already joined */
|
---|
468 | return err;
|
---|
469 | }
|
---|
470 | }
|
---|
471 | }
|
---|
472 |
|
---|
473 | return err;
|
---|
474 | }
|
---|
475 |
|
---|
476 | /**
|
---|
477 | * @ingroup igmp
|
---|
478 | * Join a group on one network interface.
|
---|
479 | *
|
---|
480 | * @param netif the network interface which should join a new group
|
---|
481 | * @param groupaddr the ip address of the group which to join
|
---|
482 | * @return ERR_OK if group was joined on the netif, an err_t otherwise
|
---|
483 | */
|
---|
484 | err_t
|
---|
485 | igmp_joingroup_netif(struct netif *netif, const ip4_addr_t *groupaddr)
|
---|
486 | {
|
---|
487 | struct igmp_group *group;
|
---|
488 |
|
---|
489 | LWIP_ASSERT_CORE_LOCKED();
|
---|
490 |
|
---|
491 | /* make sure it is multicast address */
|
---|
492 | LWIP_ERROR("igmp_joingroup_netif: attempt to join non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
|
---|
493 | LWIP_ERROR("igmp_joingroup_netif: attempt to join allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
|
---|
494 |
|
---|
495 | /* make sure it is an igmp-enabled netif */
|
---|
496 | LWIP_ERROR("igmp_joingroup_netif: attempt to join on non-IGMP netif", netif->flags & NETIF_FLAG_IGMP, return ERR_VAL;);
|
---|
497 |
|
---|
498 | /* find group or create a new one if not found */
|
---|
499 | group = igmp_lookup_group(netif, groupaddr);
|
---|
500 |
|
---|
501 | if (group != NULL) {
|
---|
502 | /* This should create a new group, check the state to make sure */
|
---|
503 | if (group->group_state != IGMP_GROUP_NON_MEMBER) {
|
---|
504 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
|
---|
505 | } else {
|
---|
506 | /* OK - it was new group */
|
---|
507 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: join to new group: "));
|
---|
508 | ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
|
---|
509 | LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
|
---|
510 |
|
---|
511 | /* If first use of the group, allow the group at the MAC level */
|
---|
512 | if ((group->use == 0) && (netif->igmp_mac_filter != NULL)) {
|
---|
513 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: igmp_mac_filter(ADD "));
|
---|
514 | ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
|
---|
515 | LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void *)netif));
|
---|
516 | netif->igmp_mac_filter(netif, groupaddr, NETIF_ADD_MAC_FILTER);
|
---|
517 | }
|
---|
518 |
|
---|
519 | IGMP_STATS_INC(igmp.tx_join);
|
---|
520 | igmp_send(netif, group, IGMP_V2_MEMB_REPORT);
|
---|
521 |
|
---|
522 | igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
|
---|
523 |
|
---|
524 | /* Need to work out where this timer comes from */
|
---|
525 | group->group_state = IGMP_GROUP_DELAYING_MEMBER;
|
---|
526 | }
|
---|
527 | /* Increment group use */
|
---|
528 | group->use++;
|
---|
529 | /* Join on this interface */
|
---|
530 | return ERR_OK;
|
---|
531 | } else {
|
---|
532 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: Not enough memory to join to group\n"));
|
---|
533 | return ERR_MEM;
|
---|
534 | }
|
---|
535 | }
|
---|
536 |
|
---|
537 | /**
|
---|
538 | * @ingroup igmp
|
---|
539 | * Leave a group on one network interface.
|
---|
540 | *
|
---|
541 | * @param ifaddr ip address of the network interface which should leave a group
|
---|
542 | * @param groupaddr the ip address of the group which to leave
|
---|
543 | * @return ERR_OK if group was left on the netif(s), an err_t otherwise
|
---|
544 | */
|
---|
545 | err_t
|
---|
546 | igmp_leavegroup(const ip4_addr_t *ifaddr, const ip4_addr_t *groupaddr)
|
---|
547 | {
|
---|
548 | err_t err = ERR_VAL; /* no matching interface */
|
---|
549 | struct netif *netif;
|
---|
550 |
|
---|
551 | LWIP_ASSERT_CORE_LOCKED();
|
---|
552 |
|
---|
553 | /* make sure it is multicast address */
|
---|
554 | LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
|
---|
555 | LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
|
---|
556 |
|
---|
557 | /* loop through netif's */
|
---|
558 | NETIF_FOREACH(netif) {
|
---|
559 | /* Should we leave this interface ? */
|
---|
560 | if ((netif->flags & NETIF_FLAG_IGMP) && ((ip4_addr_isany(ifaddr) || ip4_addr_cmp(netif_ip4_addr(netif), ifaddr)))) {
|
---|
561 | err_t res = igmp_leavegroup_netif(netif, groupaddr);
|
---|
562 | if (err != ERR_OK) {
|
---|
563 | /* Store this result if we have not yet gotten a success */
|
---|
564 | err = res;
|
---|
565 | }
|
---|
566 | }
|
---|
567 | }
|
---|
568 |
|
---|
569 | return err;
|
---|
570 | }
|
---|
571 |
|
---|
572 | /**
|
---|
573 | * @ingroup igmp
|
---|
574 | * Leave a group on one network interface.
|
---|
575 | *
|
---|
576 | * @param netif the network interface which should leave a group
|
---|
577 | * @param groupaddr the ip address of the group which to leave
|
---|
578 | * @return ERR_OK if group was left on the netif, an err_t otherwise
|
---|
579 | */
|
---|
580 | err_t
|
---|
581 | igmp_leavegroup_netif(struct netif *netif, const ip4_addr_t *groupaddr)
|
---|
582 | {
|
---|
583 | struct igmp_group *group;
|
---|
584 |
|
---|
585 | LWIP_ASSERT_CORE_LOCKED();
|
---|
586 |
|
---|
587 | /* make sure it is multicast address */
|
---|
588 | LWIP_ERROR("igmp_leavegroup_netif: attempt to leave non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
|
---|
589 | LWIP_ERROR("igmp_leavegroup_netif: attempt to leave allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
|
---|
590 |
|
---|
591 | /* make sure it is an igmp-enabled netif */
|
---|
592 | LWIP_ERROR("igmp_leavegroup_netif: attempt to leave on non-IGMP netif", netif->flags & NETIF_FLAG_IGMP, return ERR_VAL;);
|
---|
593 |
|
---|
594 | /* find group */
|
---|
595 | group = igmp_lookfor_group(netif, groupaddr);
|
---|
596 |
|
---|
597 | if (group != NULL) {
|
---|
598 | /* Only send a leave if the flag is set according to the state diagram */
|
---|
599 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: Leaving group: "));
|
---|
600 | ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
|
---|
601 | LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
|
---|
602 |
|
---|
603 | /* If there is no other use of the group */
|
---|
604 | if (group->use <= 1) {
|
---|
605 | /* Remove the group from the list */
|
---|
606 | igmp_remove_group(netif, group);
|
---|
607 |
|
---|
608 | /* If we are the last reporter for this group */
|
---|
609 | if (group->last_reporter_flag) {
|
---|
610 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: sending leaving group\n"));
|
---|
611 | IGMP_STATS_INC(igmp.tx_leave);
|
---|
612 | igmp_send(netif, group, IGMP_LEAVE_GROUP);
|
---|
613 | }
|
---|
614 |
|
---|
615 | /* Disable the group at the MAC level */
|
---|
616 | if (netif->igmp_mac_filter != NULL) {
|
---|
617 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: igmp_mac_filter(DEL "));
|
---|
618 | ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
|
---|
619 | LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void *)netif));
|
---|
620 | netif->igmp_mac_filter(netif, groupaddr, NETIF_DEL_MAC_FILTER);
|
---|
621 | }
|
---|
622 |
|
---|
623 | /* Free group struct */
|
---|
624 | memp_free(MEMP_IGMP_GROUP, group);
|
---|
625 | } else {
|
---|
626 | /* Decrement group use */
|
---|
627 | group->use--;
|
---|
628 | }
|
---|
629 | return ERR_OK;
|
---|
630 | } else {
|
---|
631 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: not member of group\n"));
|
---|
632 | return ERR_VAL;
|
---|
633 | }
|
---|
634 | }
|
---|
635 |
|
---|
636 | /**
|
---|
637 | * The igmp timer function (both for NO_SYS=1 and =0)
|
---|
638 | * Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
|
---|
639 | */
|
---|
640 | void
|
---|
641 | igmp_tmr(void)
|
---|
642 | {
|
---|
643 | struct netif *netif;
|
---|
644 |
|
---|
645 | NETIF_FOREACH(netif) {
|
---|
646 | struct igmp_group *group = netif_igmp_data(netif);
|
---|
647 |
|
---|
648 | while (group != NULL) {
|
---|
649 | if (group->timer > 0) {
|
---|
650 | group->timer--;
|
---|
651 | if (group->timer == 0) {
|
---|
652 | igmp_timeout(netif, group);
|
---|
653 | }
|
---|
654 | }
|
---|
655 | group = group->next;
|
---|
656 | }
|
---|
657 | }
|
---|
658 | }
|
---|
659 |
|
---|
660 | /**
|
---|
661 | * Called if a timeout for one group is reached.
|
---|
662 | * Sends a report for this group.
|
---|
663 | *
|
---|
664 | * @param group an igmp_group for which a timeout is reached
|
---|
665 | */
|
---|
666 | static void
|
---|
667 | igmp_timeout(struct netif *netif, struct igmp_group *group)
|
---|
668 | {
|
---|
669 | /* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group
|
---|
670 | (unless it is the allsystems group) */
|
---|
671 | if ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
|
---|
672 | (!(ip4_addr_cmp(&(group->group_address), &allsystems)))) {
|
---|
673 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
|
---|
674 | ip4_addr_debug_print_val(IGMP_DEBUG, group->group_address);
|
---|
675 | LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void *)netif));
|
---|
676 |
|
---|
677 | group->group_state = IGMP_GROUP_IDLE_MEMBER;
|
---|
678 |
|
---|
679 | IGMP_STATS_INC(igmp.tx_report);
|
---|
680 | igmp_send(netif, group, IGMP_V2_MEMB_REPORT);
|
---|
681 | }
|
---|
682 | }
|
---|
683 |
|
---|
684 | /**
|
---|
685 | * Start a timer for an igmp group
|
---|
686 | *
|
---|
687 | * @param group the igmp_group for which to start a timer
|
---|
688 | * @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
|
---|
689 | * every call to igmp_tmr())
|
---|
690 | */
|
---|
691 | static void
|
---|
692 | igmp_start_timer(struct igmp_group *group, u8_t max_time)
|
---|
693 | {
|
---|
694 | #ifdef LWIP_RAND
|
---|
695 | group->timer = (u16_t)(max_time > 2 ? (LWIP_RAND() % max_time) : 1);
|
---|
696 | #else /* LWIP_RAND */
|
---|
697 | /* ATTENTION: use this only if absolutely necessary! */
|
---|
698 | group->timer = max_time / 2;
|
---|
699 | #endif /* LWIP_RAND */
|
---|
700 |
|
---|
701 | if (group->timer == 0) {
|
---|
702 | group->timer = 1;
|
---|
703 | }
|
---|
704 | }
|
---|
705 |
|
---|
706 | /**
|
---|
707 | * Delaying membership report for a group if necessary
|
---|
708 | *
|
---|
709 | * @param group the igmp_group for which "delaying" membership report
|
---|
710 | * @param maxresp query delay
|
---|
711 | */
|
---|
712 | static void
|
---|
713 | igmp_delaying_member(struct igmp_group *group, u8_t maxresp)
|
---|
714 | {
|
---|
715 | if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) ||
|
---|
716 | ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
|
---|
717 | ((group->timer == 0) || (maxresp < group->timer)))) {
|
---|
718 | igmp_start_timer(group, maxresp);
|
---|
719 | group->group_state = IGMP_GROUP_DELAYING_MEMBER;
|
---|
720 | }
|
---|
721 | }
|
---|
722 |
|
---|
723 |
|
---|
724 | /**
|
---|
725 | * Sends an IP packet on a network interface. This function constructs the IP header
|
---|
726 | * and calculates the IP header checksum. If the source IP address is NULL,
|
---|
727 | * the IP address of the outgoing network interface is filled in as source address.
|
---|
728 | *
|
---|
729 | * @param p the packet to send (p->payload points to the data, e.g. next
|
---|
730 | protocol header; if dest == LWIP_IP_HDRINCL, p already includes an
|
---|
731 | IP header and p->payload points to that IP header)
|
---|
732 | * @param src the source IP address to send from (if src == IP4_ADDR_ANY, the
|
---|
733 | * IP address of the netif used to send is used as source address)
|
---|
734 | * @param dest the destination IP address to send the packet to
|
---|
735 | * @param netif the netif on which to send this packet
|
---|
736 | * @return ERR_OK if the packet was sent OK
|
---|
737 | * ERR_BUF if p doesn't have enough space for IP/LINK headers
|
---|
738 | * returns errors returned by netif->output
|
---|
739 | */
|
---|
740 | static err_t
|
---|
741 | igmp_ip_output_if(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest, struct netif *netif)
|
---|
742 | {
|
---|
743 | /* This is the "router alert" option */
|
---|
744 | u16_t ra[2];
|
---|
745 | ra[0] = PP_HTONS(ROUTER_ALERT);
|
---|
746 | ra[1] = 0x0000; /* Router shall examine packet */
|
---|
747 | IGMP_STATS_INC(igmp.xmit);
|
---|
748 | return ip4_output_if_opt(p, src, dest, IGMP_TTL, 0, IP_PROTO_IGMP, netif, ra, ROUTER_ALERTLEN);
|
---|
749 | }
|
---|
750 |
|
---|
751 | /**
|
---|
752 | * Send an igmp packet to a specific group.
|
---|
753 | *
|
---|
754 | * @param group the group to which to send the packet
|
---|
755 | * @param type the type of igmp packet to send
|
---|
756 | */
|
---|
757 | static void
|
---|
758 | igmp_send(struct netif *netif, struct igmp_group *group, u8_t type)
|
---|
759 | {
|
---|
760 | struct pbuf *p = NULL;
|
---|
761 | struct igmp_msg *igmp = NULL;
|
---|
762 | ip4_addr_t src = *IP4_ADDR_ANY4;
|
---|
763 | ip4_addr_t *dest = NULL;
|
---|
764 |
|
---|
765 | /* IP header + "router alert" option + IGMP header */
|
---|
766 | p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
|
---|
767 |
|
---|
768 | if (p) {
|
---|
769 | igmp = (struct igmp_msg *)p->payload;
|
---|
770 | LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
|
---|
771 | (p->len >= sizeof(struct igmp_msg)));
|
---|
772 | ip4_addr_copy(src, *netif_ip4_addr(netif));
|
---|
773 |
|
---|
774 | if (type == IGMP_V2_MEMB_REPORT) {
|
---|
775 | dest = &(group->group_address);
|
---|
776 | ip4_addr_copy(igmp->igmp_group_address, group->group_address);
|
---|
777 | group->last_reporter_flag = 1; /* Remember we were the last to report */
|
---|
778 | } else {
|
---|
779 | if (type == IGMP_LEAVE_GROUP) {
|
---|
780 | dest = &allrouters;
|
---|
781 | ip4_addr_copy(igmp->igmp_group_address, group->group_address);
|
---|
782 | }
|
---|
783 | }
|
---|
784 |
|
---|
785 | if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
|
---|
786 | igmp->igmp_msgtype = type;
|
---|
787 | igmp->igmp_maxresp = 0;
|
---|
788 | igmp->igmp_checksum = 0;
|
---|
789 | igmp->igmp_checksum = inet_chksum(igmp, IGMP_MINLEN);
|
---|
790 |
|
---|
791 | igmp_ip_output_if(p, &src, dest, netif);
|
---|
792 | }
|
---|
793 |
|
---|
794 | pbuf_free(p);
|
---|
795 | } else {
|
---|
796 | LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
|
---|
797 | IGMP_STATS_INC(igmp.memerr);
|
---|
798 | }
|
---|
799 | }
|
---|
800 |
|
---|
801 | #endif /* LWIP_IPV4 && LWIP_IGMP */
|
---|