/* *------------------------------------------------------------------ * Copyright (c) 2018 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *------------------------------------------------------------------ */ #include <igmp/igmp_query.h> #include <igmp/igmp_pkt.h> static f64 igmp_get_random_resp_delay (const igmp_header_t * header) { u32 seed; seed = vlib_time_now (vlib_get_main ()); return ((random_f64 (&seed) * igmp_header_get_max_resp_time (header))); } static ip46_address_t * igmp_query_mk_source_list (const igmp_membership_query_v3_t * q) { ip46_address_t *srcs = NULL; const ip4_address_t *s; u16 ii, n; /* * we validated this packet when we accepted it in the DP, so * this number is safe to use */ n = clib_net_to_host_u16 (q->n_src_addresses); if (0 == n) return (NULL); vec_validate (srcs, n - 1); s = q->src_addresses; for (ii = 0; ii < n; ii++) { srcs[ii].ip4 = *s; s++; } return (srcs); } static void igmp_send_group_report_v3 (u32 obj, void *data) { igmp_pkt_build_report_t br; igmp_config_t *config; ip46_address_t *srcs; igmp_group_t *group; igmp_main_t *im; im = &igmp_main; srcs = data; group = pool_elt_at_index (im->groups, obj); config = pool_elt_at_index (im->configs, group->config); igmp_pkt_build_report_init (&br, config->sw_if_index); ASSERT (group->timers[IGMP_GROUP_TIMER_QUERY_REPLY] != IGMP_TIMER_ID_INVALID); IGMP_DBG ("send-group-report: %U", format_vnet_sw_if_index_name, vnet_get_main (), config->sw_if_index); if (NULL == srcs) { /* * there were no sources specified, so this is a group-specific query. * We should respond with all our sources */ igmp_pkt_report_v3_add_group (&br, group, IGMP_MEMBERSHIP_GROUP_mode_is_include); } else { /* * the sources stored in the timer object are the combined set of sources * to be required. We need to respond only to those queried, not our full set. */ ip46_address_t *intersect; intersect = igmp_group_new_intersect_present (group, IGMP_FILTER_MODE_INCLUDE, srcs); if (vec_len (intersect)) { igmp_pkt_report_v3_add_report (&br, group->key, intersect, IGMP_MEMBERSHIP_GROUP_mode_is_include); vec_free (intersect); } } igmp_pkt_report_v3_send (&br); igmp_timer_retire (&group->timers[IGMP_GROUP_TIMER_QUERY_REPLY]); vec_free (srcs); } static igmp_membership_group_v3_type_t igmp_filter_mode_to_report_type (igmp_filter_mode_t mode) { switch (mode) { case IGMP_FILTER_MODE_INCLUDE: return (IGMP_MEMBERSHIP_GROUP_mode_is_include); case IGMP_FILTER_MODE_EXCLUDE: return (IGMP_MEMBERSHIP_GROUP_mode_is_exclude); } return (IGMP_MEMBERSHIP_GROUP_mode_is_include); } /** * Send igmp membership general report. */ static void igmp_send_general_report_v3 (u32 obj, void *data) { igmp_pkt_build_report_t br; igmp_config_t *config; igmp_group_t *group; igmp_main_t *im; im = &igmp_main; config = pool_elt_at_index (im->configs, obj); ASSERT (config->timers[IGMP_CONFIG_TIMER_GENERAL_REPORT] != IGMP_TIMER_ID_INVALID); igmp_timer_retire (&config->timers[IGMP_CONFIG_TIMER_GENERAL_REPORT]); IGMP_DBG ("send-general-report: %U", format_vnet_sw_if_index_name, vnet_get_main (), config->sw_if_index); igmp_pkt_build_report_init (&br, config->sw_if_index); FOR_EACH_GROUP (group, config, ({ igmp_pkt_report_v3_add_group (&br, group, igmp_filter_mode_to_report_type(group->router_filter_mode)); })); igmp_pkt_report_v3_send (&br); } /** * Called from the main thread on reception of a Query message */ void igmp_handle_query (const igmp_query_args_t * args) { igmp_config_t *config; config = igmp_config_lookup (args->sw_if_index); if (!config) /* * no IGMP config on the interface. quit */ return; if (IGMP_MODE_ROUTER == config->mode) { ASSERT (0); // code here for querier election */ } IGMP_DBG ("query-rx: %U", format_vnet_sw_if_index_name, vnet_get_main (), args->sw_if_index); /* Section 5.2 "When a system receives a Query, it does not respond immediately. Instead, it delays its response by a random amount of time, bounded by the Max Resp Time value derived from the Max Resp Code in the received Query message. A system may receive a variety of Queries on different interfaces and of different kinds (e.g., General Queries, Group-Specific Queries, and Group-and-Source-Specific Queries), each of which may require its own delayed response. */ if (igmp_membership_query_v3_is_general (args->query)) { IGMP_DBG ("...general-query-rx: %U", format_vnet_sw_if_index_name, vnet_get_main (), args->sw_if_index); /* * A general query has no info that needs saving from the response */ if (IGMP_TIMER_ID_INVALID == config->timers[IGMP_CONFIG_TIMER_GENERAL_REPORT]) { f64 delay = igmp_get_random_resp_delay (&args->query[0].header); IGMP_DBG ("...general-query-rx: %U schedule for %f", format_vnet_sw_if_index_name, vnet_get_main (), args->sw_if_index, delay); /* * no currently running timer, schedule a new one */ config->timers[IGMP_CONFIG_TIMER_GENERAL_REPORT] = igmp_timer_schedule (delay, igmp_config_index (config), igmp_send_general_report_v3, NULL); } /* * else * don't reschedule timers, we'll reply soon enough.. */ } else { /* * G or SG query. we'll need to save the sources quered */ igmp_key_t key = { .ip4 = args->query[0].group_address, }; ip46_address_t *srcs; igmp_timer_id_t tid; igmp_group_t *group; group = igmp_group_lookup (config, &key); /* * If there is no group config, no worries, we can ignore this * query. If the group state does come soon, we'll send a * state-change report at that time. */ if (!group) return; srcs = igmp_query_mk_source_list (args->query); tid = group->timers[IGMP_GROUP_TIMER_QUERY_REPLY]; IGMP_DBG ("...group-query-rx: %U for (%U, %U)", format_vnet_sw_if_index_name, vnet_get_main (), args->sw_if_index, format_igmp_src_addr_list, srcs, format_igmp_key, &key); if (IGMP_TIMER_ID_INVALID != tid) { /* * There is a timer already running, merge the sources list */ ip46_address_t *current, *s; current = igmp_timer_get_data (tid); vec_foreach (s, srcs) { if (~0 == vec_search_with_function (current, s, ip46_address_is_equal)) { vec_add1 (current, *s); } } igmp_timer_set_data (tid, current); } else { /* * schedule a new G-specific query */ f64 delay = igmp_get_random_resp_delay (&args->query[0].header); IGMP_DBG ("...group-query-rx: schedule:%f", delay); group->timers[IGMP_GROUP_TIMER_QUERY_REPLY] = igmp_timer_schedule (delay, igmp_group_index (group), igmp_send_group_report_v3, srcs); } } } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */